Cholesterol 7 alpha hydroxylase. Medical search

A mitochondrial cytochrome P450 enzyme that catalyzes the 1-alpha-hydroxylation of 25-hydroxyvitamin D3 (also known as 25-hydroxycholecalciferol) in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP27B1 gene, converts 25-hydroxyvitamin D3 to 1-alpha,25-dihydroxyvitamin D3 which is the active form of VITAMIN D in regulating bone growth and calcium metabolism. This enzyme is also active on plant 25-hydroxyvitamin D2 (ergocalciferol).

Food BEVERAGES that are used as nutritional substitutes for MILK.

A membrane-bound cytochrome P450 enzyme that catalyzes the 7-alpha-hydroxylation of CHOLESTEROL in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP7, converts cholesterol to 7-alpha-hydroxycholesterol which is the first and rate-limiting step in the synthesis of BILE ACIDS.

The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.

Cholesterol present in food, especially in animal products.

Cholesterol which is contained in or bound to high-density lipoproteins (HDL), including CHOLESTEROL ESTERS and free cholesterol.

An enzyme of the oxidoreductase class that catalyzes the formation of L-TYROSINE, dihydrobiopterin, and water from L-PHENYLALANINE, tetrahydrobiopterin, and oxygen. Deficiency of this enzyme may cause PHENYLKETONURIAS and PHENYLKETONURIA, MATERNAL. EC 1.14.16.1.

Cholesterol which is contained in or bound to low density lipoproteins (LDL), including CHOLESTEROL ESTERS and free cholesterol.

An adrenal microsomal cytochrome P450 enzyme that catalyzes the 21-hydroxylation of steroids in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP21 gene, converts progesterones to precursors of adrenal steroid hormones (CORTICOSTERONE; HYDROCORTISONE). Defects in CYP21 cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL).

Fatty acid esters of cholesterol which constitute about two-thirds of the cholesterol in the plasma. The accumulation of cholesterol esters in the arterial intima is a characteristic feature of atherosclerosis.

An enzyme that catalyzes the hydroxylation of TRYPTOPHAN to 5-HYDROXYTRYPTOPHAN in the presence of NADPH and molecular oxygen. It is important in the biosynthesis of SEROTONIN.

An enzyme that catalyzes the oxidation of cholesterol in the presence of molecular oxygen to 4-cholesten-3-one and hydrogen peroxide. The enzyme is not specific for cholesterol, but will also oxidize other 3-hydroxysteroids. EC 1.1.3.6.

An enzyme that catalyzes the conversion of L-tyrosine, tetrahydrobiopterin, and oxygen to 3,4-dihydroxy-L-phenylalanine, dihydrobiopterin, and water. EC 1.14.16.2.

Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.

A mixed-function oxygenase that catalyzes the hydroxylation of a prolyl-glycyl containing peptide, usually in PROTOCOLLAGEN, to a hydroxyprolylglycyl-containing-peptide. The enzyme utilizes molecular OXYGEN with a concomitant oxidative decarboxylation of 2-oxoglutarate to SUCCINATE. The enzyme occurs as a tetramer of two alpha and two beta subunits. The beta subunit of procollagen-proline dioxygenase is identical to the enzyme PROTEIN DISULFIDE-ISOMERASES.

Cytochrome P-450 monooxygenases (MIXED FUNCTION OXYGENASES) that are important in steroid biosynthesis and metabolism.

An NAPH-dependent cytochrome P450 enzyme that catalyzes the oxidation of the side chain of sterol intermediates such as the 27-hydroxylation of 5-beta-cholestane-3-alpha,7-alpha,12-alpha-triol.

A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)

Cholesterol which is contained in or bound to very low density lipoproteins (VLDL). High circulating levels of VLDL cholesterol are found in HYPERLIPOPROTEINEMIA TYPE IIB. The cholesterol on the VLDL is eventually delivered by LOW-DENSITY LIPOPROTEINS to the tissues after the catabolism of VLDL to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LDL.

Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.

A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.

A condition with abnormally high levels of CHOLESTEROL in the blood. It is defined as a cholesterol value exceeding the 95th percentile for the population.

Substances used to lower plasma CHOLESTEROL levels.

An enzyme that catalyzes the formation of cholesterol esters by the direct transfer of the fatty acid group from a fatty acyl CoA derivative. This enzyme has been found in the adrenal gland, gonads, liver, intestinal mucosa, and aorta of many mammalian species. EC 2.3.1.26.

Steroid acids and salts. The primary bile acids are derived from cholesterol in the liver and usually conjugated with glycine or taurine. The secondary bile acids are further modified by bacteria in the intestine. They play an important role in the digestion and absorption of fat. They have also been used pharmacologically, especially in the treatment of gallstones.

Steroids with a hydroxyl group at C-3 and most of the skeleton of cholestane. Additional carbon atoms may be present in the side chain. (IUPAC Steroid Nomenclature, 1987)

Plasma glycoprotein member of the serpin superfamily which inhibits TRYPSIN; NEUTROPHIL ELASTASE; and other PROTEOLYTIC ENZYMES.

A drug-metabolizing, cytochrome P-448 (P-450) enzyme which catalyzes the hydroxylation of benzopyrene to 3-hydroxybenzopyrene in the presence of reduced flavoprotein and molecular oxygen. Also acts on certain anthracene derivatives. An aspect of EC 1.14.14.1.

A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.

A group of inherited disorders of the ADRENAL GLANDS, caused by enzyme defects in the synthesis of cortisol (HYDROCORTISONE) and/or ALDOSTERONE leading to accumulation of precursors for ANDROGENS. Depending on the hormone imbalance, congenital adrenal hyperplasia can be classified as salt-wasting, hypertensive, virilizing, or feminizing. Defects in STEROID 21-HYDROXYLASE; STEROID 11-BETA-HYDROXYLASE; STEROID 17-ALPHA-HYDROXYLASE; 3-beta-hydroxysteroid dehydrogenase (3-HYDROXYSTEROID DEHYDROGENASES); TESTOSTERONE 5-ALPHA-REDUCTASE; or steroidogenic acute regulatory protein; among others, underlie these disorders.

Enzymes that catalyze the reversible reduction of alpha-carboxyl group of 3-hydroxy-3-methylglutaryl-coenzyme A to yield MEVALONIC ACID.

Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)

The rate dynamics in chemical or physical systems.

A flavoprotein that catalyzes the synthesis of protocatechuic acid from 4-hydroxybenzoate in the presence of molecular oxygen. EC 1.14.13.2.

Hypoxia-inducible factor 1, alpha subunit is a basic helix-loop-helix transcription factor that is regulated by OXYGEN availability and is targeted for degradation by VHL TUMOR SUPPRESSOR PROTEIN.

The most abundant protein component of HIGH DENSITY LIPOPROTEINS or HDL. This protein serves as an acceptor for CHOLESTEROL released from cells thus promoting efflux of cholesterol to HDL then to the LIVER for excretion from the body (reverse cholesterol transport). It also acts as a cofactor for LECITHIN CHOLESTEROL ACYLTRANSFERASE that forms CHOLESTEROL ESTERS on the HDL particles. Mutations of this gene APOA1 cause HDL deficiency, such as in FAMILIAL ALPHA LIPOPROTEIN DEFICIENCY DISEASE and in some patients with TANGIER DISEASE.

An emulsifying agent produced in the LIVER and secreted into the DUODENUM. Its composition includes BILE ACIDS AND SALTS; CHOLESTEROL; and ELECTROLYTES. It aids DIGESTION of fats in the duodenum.

Cholesterol which is substituted by a hydroxy group in any position.

A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.

A family of sterols commonly found in plants and plant oils. Alpha-, beta-, and gamma-isomers have been characterized.

Cyclic GLUCANS consisting of seven (7) glucopyranose units linked by 1,4-glycosidic bonds.

A superfamily of large integral ATP-binding cassette membrane proteins whose expression pattern is consistent with a role in lipid (cholesterol) efflux. It is implicated in TANGIER DISEASE characterized by accumulation of cholesteryl ester in various tissues.

Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.

One of the two major pharmacological subdivisions of adrenergic receptors that were originally defined by the relative potencies of various adrenergic compounds. The alpha receptors were initially described as excitatory receptors that post-junctionally stimulate SMOOTH MUSCLE contraction. However, further analysis has revealed a more complex picture involving several alpha receptor subtypes and their involvement in feedback regulation.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.

Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.

A class of organic compounds known as STEROLS or STEROIDS derived from plants.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

A homologous group of cyclic GLUCANS consisting of alpha-1,4 bound glucose units obtained by the action of cyclodextrin glucanotransferase on starch or similar substrates. The enzyme is produced by certain species of Bacillus. Cyclodextrins form inclusion complexes with a wide variety of substances.

The process of converting an acid into an alkyl or aryl derivative. Most frequently the process consists of the reaction of an acid with an alcohol in the presence of a trace of mineral acid as catalyst or the reaction of an acyl chloride with an alcohol. Esterification can also be accomplished by enzymatic processes.

Fats present in food, especially in animal products such as meat, meat products, butter, ghee. They are present in lower amounts in nuts, seeds, and avocados.

A family of MEMBRANE TRANSPORT PROTEINS that require ATP hydrolysis for the transport of substrates across membranes. The protein family derives its name from the ATP-binding domain found on the protein.

Conditions with excess LIPIDS in the blood.

An enzyme secreted from the liver into the plasma of many mammalian species. It catalyzes the esterification of the hydroxyl group of lipoprotein cholesterol by the transfer of a fatty acid from the C-2 position of lecithin. In familial lecithin:cholesterol acyltransferase deficiency disease, the absence of the enzyme results in an excess of unesterified cholesterol in plasma. EC 2.3.1.43.

Dioxygenase enzymes that specifically hydroxylate a PROLINE residue on the HYPOXIA-INDUCIBLE FACTOR 1, ALPHA SUBUNIT. They are OXYGEN-dependent enzymes that play an important role in mediating cellular adaptive responses to HYPOXIA.

A group of autosomal recessive disorders marked by a deficiency of the hepatic enzyme PHENYLALANINE HYDROXYLASE or less frequently by reduced activity of DIHYDROPTERIDINE REDUCTASE (i.e., atypical phenylketonuria). Classical phenylketonuria is caused by a severe deficiency of phenylalanine hydroxylase and presents in infancy with developmental delay; SEIZURES; skin HYPOPIGMENTATION; ECZEMA; and demyelination in the central nervous system. (From Adams et al., Principles of Neurology, 6th ed, p952).

A cholesterol derivative found in human feces, gallstones, eggs, and other biological matter.

The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.

Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.

RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.

Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.

Elements of limited time intervals, contributing to particular results or situations.

A fungal metabolite isolated from cultures of Aspergillus terreus. The compound is a potent anticholesteremic agent. It inhibits 3-hydroxy-3-methylglutaryl coenzyme A reductase (HYDROXYMETHYLGLUTARYL COA REDUCTASES), which is the rate-limiting enzyme in cholesterol biosynthesis. It also stimulates the production of low-density lipoprotein receptors in the liver.

A strongly basic anion exchange resin whose main constituent is polystyrene trimethylbenzylammonium Cl(-) anion.

An intermediate in the synthesis of cholesterol.

Proteins that bind to and transfer CHOLESTEROL ESTERS between LIPOPROTEINS such as LOW-DENSITY LIPOPROTEINS and HIGH-DENSITY LIPOPROTEINS.

Receptors on the plasma membrane of nonhepatic cells that specifically bind LDL. The receptors are localized in specialized regions called coated pits. Hypercholesteremia is caused by an allelic genetic defect of three types: 1, receptors do not bind to LDL; 2, there is reduced binding of LDL; and 3, there is normal binding but no internalization of LDL. In consequence, entry of cholesterol esters into the cell is impaired and the intracellular feedback by cholesterol on 3-hydroxy-3-methylglutaryl CoA reductase is lacking.

Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.

A complex of polyene antibiotics obtained from Streptomyces filipinensis. Filipin III alters membrane function by interfering with membrane sterols, inhibits mitochondrial respiration, and is proposed as an antifungal agent. Filipins I, II, and IV are less important.

Thickening and loss of elasticity of the walls of ARTERIES of all sizes. There are many forms classified by the types of lesions and arteries involved, such as ATHEROSCLEROSIS with fatty lesions in the ARTERIAL INTIMA of medium and large muscular arteries.

A drug-metabolizing, cytochrome P-450 enzyme which catalyzes the hydroxylation of aniline to hydroxyaniline in the presence of reduced flavoprotein and molecular oxygen. EC 1.14.14.-.

Uptake of substances through the lining of the INTESTINES.

Major structural proteins of triacylglycerol-rich LIPOPROTEINS. There are two forms, apolipoprotein B-100 and apolipoprotein B-48, both derived from a single gene. ApoB-100 expressed in the liver is found in low-density lipoproteins (LIPOPROTEINS, LDL; LIPOPROTEINS, VLDL). ApoB-48 expressed in the intestine is found in CHYLOMICRONS. They are important in the biosynthesis, transport, and metabolism of triacylglycerol-rich lipoproteins. Plasma Apo-B levels are high in atherosclerotic patients but non-detectable in ABETALIPOPROTEINEMIA.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

Proteins prepared by recombinant DNA technology.

Compounds that inhibit HMG-CoA reductases. They have been shown to directly lower cholesterol synthesis.

A class of protein components which can be found in several lipoproteins including HIGH-DENSITY LIPOPROTEINS; VERY-LOW-DENSITY LIPOPROTEINS; and CHYLOMICRONS. Synthesized in most organs, Apo E is important in the global transport of lipids and cholesterol throughout the body. Apo E is also a ligand for LDL receptors (RECEPTORS, LDL) that mediates the binding, internalization, and catabolism of lipoprotein particles in cells. There are several allelic isoforms (such as E2, E3, and E4). Deficiency or defects in Apo E are causes of HYPERLIPOPROTEINEMIA TYPE III.

The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.

Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.

A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.

Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.

A member of the NICOTINIC ACETYLCHOLINE RECEPTOR subfamily of the LIGAND-GATED ION CHANNEL family. It consists entirely of pentameric a7 subunits expressed in the CNS, autonomic nervous system, vascular system, lymphocytes and spleen.

The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.

Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.

An enzyme that catalyzes the hydrolysis of CHOLESTEROL ESTERS and some other sterol esters, to liberate cholesterol plus a fatty acid anion.

Established cell cultures that have the potential to propagate indefinitely.

Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.

Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.

The relationship between the dose of an administered drug and the response of the organism to the drug.

A member of the P450 superfamily, this enzyme catalyzes the first oxidative step of the phenylpropanoid pathway in higher PLANTS by transforming trans-cinnamate into p-coumarate.

Presence or formation of GALLSTONES in the BILIARY TRACT, usually in the gallbladder (CHOLECYSTOLITHIASIS) or the common bile duct (CHOLEDOCHOLITHIASIS).

A broad category of receptor-like proteins that may play a role in transcriptional-regulation in the CELL NUCLEUS. Many of these proteins are similar in structure to known NUCLEAR RECEPTORS but appear to lack a functional ligand-binding domain, while in other cases the specific ligands have yet to be identified.

Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)

A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.

The parts of a macromolecule that directly participate in its specific combination with another molecule.

The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.

Cholesterol derivatives having an additional double bond in any position. 24-Dehydrocholesterol is DESMOSTEROL. The other most prevalent dehydrocholesterol is the 7-isomer. This compound is a precursor of cholesterol and of vitamin D3.

A triterpene that derives from the chair-boat-chair-boat folding of 2,3-oxidosqualene. It is metabolized to CHOLESTEROL and CUCURBITACINS.

A mitochondrial cytochrome P450 enzyme that catalyzes the side-chain cleavage of C27 cholesterol to C21 pregnenolone in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP11A1 gene, catalyzes the breakage between C20 and C22 which is the initial and rate-limiting step in the biosynthesis of various gonadal and adrenal steroid hormones.

An autosomal recessive lipid storage disorder due to mutation of the gene CYP27A1 encoding a CHOLESTANETRIOL 26-MONOOXYGENASE. It is characterized by large deposits of CHOLESTEROL and CHOLESTANOL in various tissues resulting in xanthomatous swelling of tendons, early CATARACT, and progressive neurological symptoms.

A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS.

Unsaturated derivatives of the steroid androstane containing at least one double bond at any site in any of the rings.

Cell surface receptor for LAMININ, epiligrin, FIBRONECTINS, entactin, and COLLAGEN. Integrin alpha3beta1 is the major integrin present in EPITHELIAL CELLS, where it plays a role in the assembly of BASEMENT MEMBRANE as well as in cell migration, and may regulate the functions of other integrins. Two alternatively spliced isoforms of the alpha subunit (INTEGRIN ALPHA3), are differentially expressed in different cell types.

The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.

An integrin alpha subunit that is unique in that it does not contain an I domain, and its proteolytic cleavage site is near the middle of the extracellular portion of the polypeptide rather than close to the membrane as in other integrin alpha subunits.

An integrin alpha subunit that primarily associates with INTEGRIN BETA1 or INTEGRIN BETA4 to form laminin-binding heterodimers. Integrin alpha6 has two alternatively spliced isoforms: integrin alpha6A and integrin alpha6B, which differ in their cytoplasmic domains and are regulated in a tissue-specific and developmental stage-specific manner.

A diet that contributes to the development and acceleration of ATHEROGENESIS.

The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.

Substances that lower the levels of certain LIPIDS in the BLOOD. They are used to treat HYPERLIPIDEMIAS.

A class of lipoproteins of very light (0.93-1.006 g/ml) large size (30-80 nm) particles with a core composed mainly of TRIGLYCERIDES and a surface monolayer of PHOSPHOLIPIDS and CHOLESTEROL into which are imbedded the apolipoproteins B, E, and C. VLDL facilitates the transport of endogenously made triglycerides to extrahepatic tissues. As triglycerides and Apo C are removed, VLDL is converted to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LOW-DENSITY LIPOPROTEINS from which cholesterol is delivered to the extrahepatic tissues.

An integrin found in FIBROBLASTS; PLATELETS; MONOCYTES, and LYMPHOCYTES. Integrin alpha5beta1 is the classical receptor for FIBRONECTIN, but it also functions as a receptor for LAMININ and several other EXTRACELLULAR MATRIX PROTEINS.

The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.

Blocking of a blood vessel by CHOLESTEROL-rich atheromatous deposits, generally occurring in the flow from a large artery to small arterial branches. It is also called arterial-arterial embolization or atheroembolism which may be spontaneous or iatrogenic. Patients with spontaneous atheroembolism often have painful, cyanotic digits of acute onset.

Derivatives of the saturated steroid cholestane with methyl groups at C-18 and C-19 and an iso-octyl side chain at C-17.

The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)

Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.

Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.

Transport proteins that carry specific substances in the blood or across cell membranes.

One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.

A family of scavenger receptors that are predominately localized to CAVEOLAE of the PLASMA MEMBRANE and bind HIGH DENSITY LIPOPROTEINS.

A pair of glands located at the cranial pole of each of the two KIDNEYS. Each adrenal gland is composed of two distinct endocrine tissues with separate embryonic origins, the ADRENAL CORTEX producing STEROIDS and the ADRENAL MEDULLA producing NEUROTRANSMITTERS.

An interleukin-1 subtype that occurs as a membrane-bound pro-protein form that is cleaved by proteases to form a secreted mature form. Unlike INTERLEUKIN-1BETA both membrane-bound and secreted forms of interleukin-1alpha are biologically active.

An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.

A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.

Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in enzyme synthesis.

Lipid-laden macrophages originating from monocytes or from smooth muscle cells.

Integrin alpha4beta1 is a FIBRONECTIN and VCAM-1 receptor present on LYMPHOCYTES; MONOCYTES; EOSINOPHILS; NK CELLS and thymocytes. It is involved in both cell-cell and cell- EXTRACELLULAR MATRIX adhesion and plays a role in INFLAMMATION, hematopoietic cell homing and immune function, and has been implicated in skeletal MYOGENESIS; NEURAL CREST migration and proliferation, lymphocyte maturation and morphogenesis of the PLACENTA and HEART.

Regular course of eating and drinking adopted by a person or animal.

Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.

Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.

Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.

Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.

A derivative of LOVASTATIN and potent competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HYDROXYMETHYLGLUTARYL COA REDUCTASES), which is the rate-limiting enzyme in cholesterol biosynthesis. It may also interfere with steroid hormone production. Due to the induction of hepatic LDL RECEPTORS, it increases breakdown of LDL CHOLESTEROL.

A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.

A group of autosomal recessive disorders in which harmful quantities of lipids accumulate in the viscera and the central nervous system. They can be caused by deficiencies of enzyme activities (SPHINGOMYELIN PHOSPHODIESTERASE) or defects in intracellular transport, resulting in the accumulation of SPHINGOMYELINS and CHOLESTEROL. There are various subtypes based on their clinical and genetic differences.

An integrin found on fibroblasts, platelets, endothelial and epithelial cells, and lymphocytes where it functions as a receptor for COLLAGEN and LAMININ. Although originally referred to as the collagen receptor, it is one of several receptors for collagen. Ligand binding to integrin alpha2beta1 triggers a cascade of intracellular signaling, including activation of p38 MAP kinase.

An enzyme that catalyzes the HYDROXYLATION of gamma-butyrobetaine to L-CARNITINE. It is the last enzyme in the biosynthetic pathway of L-CARNITINE and is dependent on alpha-ketoglutarate; IRON; ASCORBIC ACID; and OXYGEN.

The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.

The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms.

A condition marked by the development of widespread xanthomas, yellow tumor-like structures filled with lipid deposits. Xanthomas can be found in a variety of tissues including the SKIN; TENDONS; joints of KNEES and ELBOWS. Xanthomatosis is associated with disturbance of LIPID METABOLISM and formation of FOAM CELLS.

Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.

A subclass of alpha-adrenergic receptors found on both presynaptic and postsynaptic membranes where they signal through Gi-Go G-PROTEINS. While postsynaptic alpha-2 receptors play a traditional role in mediating the effects of ADRENERGIC AGONISTS, the subset of alpha-2 receptors found on presynaptic membranes signal the feedback inhibition of NEUROTRANSMITTER release.

Compounds based on 2-amino-4-hydroxypteridine.

A subclass of alpha-adrenergic receptors that mediate contraction of SMOOTH MUSCLE in a variety of tissues such as ARTERIOLES; VEINS; and the UTERUS. They are usually found on postsynaptic membranes and signal through GQ-G11 G-PROTEINS.

This integrin alpha subunit combines with INTEGRIN BETA1 to form a receptor (INTEGRIN ALPHA5BETA1) that binds FIBRONECTIN and LAMININ. It undergoes posttranslational cleavage into a heavy and a light chain that are connected by disulfide bonds.

A thickening and loss of elasticity of the walls of ARTERIES that occurs with formation of ATHEROSCLEROTIC PLAQUES within the ARTERIAL INTIMA.

Integrin alpha1beta1 functions as a receptor for LAMININ and COLLAGEN. It is widely expressed during development, but in the adult is the predominant laminin receptor (RECEPTORS, LAMININ) in mature SMOOTH MUSCLE CELLS, where it is important for maintenance of the differentiated phenotype of these cells. Integrin alpha1beta1 is also found in LYMPHOCYTES and microvascular endothelial cells, and may play a role in angiogenesis. In SCHWANN CELLS and neural crest cells, it is involved in cell migration. Integrin alpha1beta1 is also known as VLA-1 and CD49a-CD29.

The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.

Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.

Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.

Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.

A sterol regulatory element binding protein that regulates GENES involved in CHOLESTEROL synthesis and uptake.

An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.

An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.

The processes whereby the internal environment of an organism tends to remain balanced and stable.

The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.

A cell surface receptor mediating cell adhesion to the EXTRACELLULAR MATRIX and to other cells via binding to LAMININ. It is involved in cell migration, embryonic development, leukocyte activation and tumor cell invasiveness. Integrin alpha6beta1 is the major laminin receptor on PLATELETS; LEUKOCYTES; and many EPITHELIAL CELLS, and ligand binding may activate a number of signal transduction pathways. Alternative splicing of the cytoplasmic domain of the alpha6 subunit (INTEGRIN ALPHA6) results in the formation of A and B isoforms of the heterodimer, which are expressed in a tissue-specific manner.

A metabolite of PROGESTERONE with a hydroxyl group at the 17-alpha position. It serves as an intermediate in the biosynthesis of HYDROCORTISONE and GONADAL STEROID HORMONES.

An autosomal recessive disorder of CHOLESTEROL metabolism. It is caused by a deficiency of 7-dehydrocholesterol reductase, the enzyme that converts 7-dehydrocholesterol to cholesterol, leading to an abnormally low plasma cholesterol. This syndrome is characterized by multiple CONGENITAL ABNORMALITIES, growth deficiency, and INTELLECTUAL DISABILITY.

A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).

CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.

Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.

A nuclear transcription factor. Heterodimerization with RETINOID X RECEPTOR GAMMA is important to metabolism of LIPIDS. It is the target of FIBRATES to control HYPERLIPIDEMIAS.

Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.

Histochemical localization of immunoreactive substances using labeled antibodies as reagents.

A storage reservoir for BILE secretion. Gallbladder allows the delivery of bile acids at a high concentration and in a controlled manner, via the CYSTIC DUCT to the DUODENUM, for degradation of dietary lipid.

A group of polycyclic compounds closely related biochemically to TERPENES. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (STEROLS), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus. (From Hawley's Condensed Chemical Dictionary, 11th ed)

Cholesterol substituted in any position by a keto moiety. The 7-keto isomer inhibits 3-hydroxy-3-methylglutaryl-CoA reductase activity and inhibits cholesterol uptake in the coronary arteries and aorta in vitro.

The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.

Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.

A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).

A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.

This intrgrin is a key component of HEMIDESMOSOMES and is required for their formation and maintenance in epithelial cells. Integrin alpha6beta4 is also found on thymocytes, fibroblasts, and Schwann cells, where it functions as a laminin receptor (RECEPTORS, LAMININ) and is involved in wound healing, cell migration, and tumor invasiveness.

Intracellular receptors that can be found in the cytoplasm or in the nucleus. They bind to extracellular signaling molecules that migrate through or are transported across the CELL MEMBRANE. Many members of this class of receptors occur in the cytoplasm and are transported to the CELL NUCLEUS upon ligand-binding where they signal via DNA-binding and transcription regulation. Also included in this category are receptors found on INTRACELLULAR MEMBRANES that act via mechanisms similar to CELL SURFACE RECEPTORS.

A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).

The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.

Chinese hamster ovary cells require the coexpression of microsomal triglyceride transfer protein and cholesterol 7alpha-hydroxylase for the assembly and secretion of apolipoprotein B-containing lipoproteins. (1/481)

Due to the absence of microsomal triglyceride transfer protein (MTP), Chinese hamster ovary (CHO) cells lack the ability to translocate apoB into the lumen of the endoplasmic reticulum, causing apoB to be rapidly degraded by an N-acetyl-leucyl-leucyl-norleucinal-inhibitable process. The goal of this study was to examine if expression of MTP, whose genetic deletion is responsible for the human recessive disorder abetalipoproteinemia, would recapitulate the lipoprotein assembly pathway in CHO cells. Unexpectedly, expression of MTP mRNA and protein in CHO cells did not allow apoB-containing lipoproteins to be assembled and secreted by CHO cells expressing apoB53. Although expression of MTP in cells allowed apoB to completely enter the endoplasmic reticulum, it was degraded by a proteolytic process that was inhibited by dithiothreitol (1 mM) and chloroquine (100 microM), but resistant to N-acetyl-leucyl-leucyl-norleucinal. In marked contrast, coexpression of the liver-specific gene product cholesterol 7alpha-hydroxylase with MTP resulted in levels of MTP lipid transfer activity that were similar to those in mouse liver and allowed intact apoB53 to be secreted as a lipoprotein particle. These data suggest that, although MTP-facilitated lipid transport is not required for apoB translocation, it is required for the secretion of apoB-containing lipoproteins. We propose that, in CHO cells, MTP plays two roles in the assembly and secretion of apoB-containing lipoproteins: 1) it acts as a chaperone that facilitates apoB53 translocation, and 2) its lipid transfer activity allows apoB-containing lipoproteins to be assembled and secreted. Our results suggest that the phenotype of the cell (e.g. expression of cholesterol 7alpha-hydroxylase by the liver) may profoundly influence the metabolic relationships determining how apoB is processed into lipoproteins and/or degraded. (+info)

The influence of estrogen on hepatic cholesterol metabolism and biliary lipid secretion in rats fed fish oil. (2/481)

Both estrogen and dietary n-3 polyunsaturated fatty acids are known to be hypocholesterolemic, but appear to exert their effects by different mechanisms. In this study, the interaction between dietary fish oil (rich in n-3 polyunsaturated fatty acids) and estrogen in the regulation of hepatic cholesterol metabolism and biliary lipid secretion in rats was studied. Rats fed a low fat or a fish oil-supplemented diet for 21 days were injected with 17alpha-ethinyl estradiol (5 mg/kg body weight) or the vehicle only (control rats) once per day for 3 consecutive days. Estrogen-treatment led to a marked reduction in plasma cholesterol levels in fish oil-fed rats, which was greater than that observed with either estrogen or dietary fish oil alone. The expression of mRNA for cholesterol 7alpha-hydroxylase was decreased by estrogen in rats fed a low fat or a fish oil-supplemented diet, while the output of cholesterol (micromol/h/kg b.wt.) in the bile was unchanged in both groups. Cholesterol levels in the liver were increased by estrogen in rats given either diet, but there was a significant shift from cholesterol esterification to cholesteryl ester hydrolysis only in the fish oil-fed animals. Estrogen increased the concentration of cholesterol (micromol/ml) in the bile in rats fed the fish oil, but not the low fat diet. However, the cholesterol saturation index was unaffected. The output and concentration of total bile acid was also unaffected, but changes in the distribution of the individual bile acids were observed with estrogen treatment in both low fat and fish oil-fed groups. These results show that interaction between estrogen-treatment and dietary n-3 polyunsaturated fatty acids causes changes in hepatic cholesterol metabolism and biliary lipid secretion in rats, but does not increase the excretion of cholesterol from the body. (+info)

High plasma cholesterol in drug-induced cholestasis is associated with enhanced hepatic cholesterol synthesis. (3/481)

In alpha-naphthylisothiocyanate-treated mice, plasma phospholipid (PL) levels were elevated 10- and 13-fold at 48 and 168 h, respectively, whereas free cholesterol (FC) levels increased between 48 h (17-fold) and 168 h (39-fold). Nearly all of these lipids were localized to lipoprotein X-like particles in the low-density lipoprotein density range. The PL fatty acyl composition was indicative of biliary origin. Liver cholesterol and PL content were near normal at all time points. Hepatic hydroxymethylglutaryl CoA reductase activity was increased sixfold at 48 h, and cholesterol 7alpha-hydroxylase activity was decreased by approximately 70% between 24 and 72 h. These findings suggest a metabolic basis for the appearance of abnormal plasma lipoproteins during cholestasis. Initially, PL and bile acids appear in plasma where they serve to promote the efflux of cholesterol from hepatic cell membranes. Hepatic cholesterol synthesis is then likely stimulated in the response to the depletion of hepatic cell membranes of cholesterol. We speculate that the enhanced synthesis of cholesterol and impaired conversion to bile acids, particularly during the early phase of drug response, contribute to the accumulation of FC in the plasma. (+info)

Identification of a nuclear receptor for bile acids. (4/481)

Bile acids are essential for the solubilization and transport of dietary lipids and are the major products of cholesterol catabolism. Results presented here show that bile acids are physiological ligands for the farnesoid X receptor (FXR), an orphan nuclear receptor. When bound to bile acids, FXR repressed transcription of the gene encoding cholesterol 7alpha-hydroxylase, which is the rate-limiting enzyme in bile acid synthesis, and activated the gene encoding intestinal bile acid-binding protein, which is a candidate bile acid transporter. These results demonstrate a mechanism by which bile acids transcriptionally regulate their biosynthesis and enterohepatic transport. (+info)

CPF: an orphan nuclear receptor that regulates liver-specific expression of the human cholesterol 7alpha-hydroxylase gene. (5/481)

Cholesterol 7alpha-hydroxylase is the first and rate-limiting enzyme in a pathway through which cholesterol is metabolized to bile acids. The gene encoding cholesterol 7alpha-hydroxylase, CYP7A, is expressed exclusively in the liver. Overexpression of CYP7A in hamsters results in a reduction of serum cholesterol levels, suggesting that the enzyme plays a central role in cholesterol homeostasis. Here, we report the identification of a hepatic-specific transcription factor that binds to the promoter of the human CYP7A gene. We designate this factor CPF, for CYP7A promoter binding factor. Mutation of the CPF binding site within the CYP7A promoter abolished hepatic-specific expression of the gene in transient transfection assays. A cDNA encoding CPF was cloned and identified as a human homolog of the Drosophila orphan nuclear receptor fushi tarazu F1 (Ftz-F1). Cotransfection of a CPF expression plasmid and a CYP7A reporter gene resulted in specific induction of CYP7A-directed transcription. These observations suggest that CPF is a key regulator of human CYP7A gene expression in the liver. (+info)

Lipoprotein cholesterol uptake mediates up-regulation of bile-acid synthesis by increasing cholesterol 7alpha-hydroxylase but not sterol 27-hydroxylase gene expression in cultured rat hepatocytes. (6/481)

Lipoproteins may supply substrate for the formation of bile acids, and the amount of hepatic cholesterol can regulate bile-acid synthesis and increase cholesterol 7alpha-hydroxylase expression. However, the effect of lipoprotein cholesterol on sterol 27-hydroxylase expression and the role of different lipoproteins in regulating both enzymes are not well established. We studied the effect of different rabbit lipoproteins on cholesterol 7alpha-hydroxylase and sterol 27-hydroxylase in cultured rat hepatocytes. beta-Migrating very-low-density lipoprotein (betaVLDL) and intermediate-density lipoprotein (IDL) caused a significant increase in the intracellular cholesteryl ester content of cells (2. 3- and 2-fold, respectively) at a concentration of 200 microgram of cholesterol/ml, whereas high-density lipoprotein (HDL, 50% v/v), containing no apolipoprotein E (apo E), showed no effect after a 24-h incubation. betaVLDL and IDL increased bile-acid synthesis (1. 9- and 1.6-fold, respectively) by up-regulation of cholesterol 7alpha-hydroxylase activity (1.7- and 1.5-fold, respectively). Dose- and time-dependent changes in cholesterol 7alpha-hydroxylase mRNA levels and gene expression underlie the increase in enzyme activity. Incubation of cells with HDL showed no effect. Sterol 27-hydroxylase gene expression was not affected by any of the lipoproteins added. Transient-expression experiments in hepatocytes, transfected with a promoter-reporter construct containing the proximal 348 nucleotides of the rat cholesterol 7alpha-hydroxylase promoter, showed an enhanced gene transcription (2-fold) with betaVLDL, indicating that a sequence important for a cholesterol-induced transcriptional response is located in this part of the cholesterol 7alpha-hydroxylase gene. The extent of stimulation of cholesterol 7alpha-hydroxylase is associated with the apo E content of the lipoprotein particle, which is important in the uptake of lipoprotein cholesterol. We conclude that physiological concentrations of cholesterol in apo E-containing lipoproteins increase bile-acid synthesis by stimulating cholesterol 7alpha-hydroxylase gene transcription, whereas HDL has no effect and sterol 27-hydroxylase is not affected. (+info)

Selective uptake of cholesteryl ester from low density lipoprotein is involved in HepG2 cell cholesterol homeostasis. (7/481)

Low density lipoprotein (LDL) can follow either a holoparticle uptake pathway, initiated by the LDL receptor (LDLr), and be completely degraded, or it can deliver its cholesteryl esters (CE) selectively to HepG2 cells. Although high density lipoprotein-CE selective uptake has been shown to be linked to cell cholesterol homeostasis in nonhepatic cells, there is no available information on the effect of LDL-CE selective uptake on hepatic cell cholesterol homeostasis. In order to define the role of the LDL-CE selective uptake pathway in hepatic cell cholesterol homeostasis, we used a cellular model that expresses constitutively a LDLr antisense mRNA and that shows LDLr activity at 31% the normal level (HepG2-all cells). The addition of a specific antibody anti-LDLr (IgG-C7) reduces LDL protein degradation (LDLr activity) to 7%. This cellular model therefore reflects, above all, LDL-CE selective uptake activity when incubated with LDL. The inactivation of LDLr reduces LDL-protein association by 78% and LDL-CE association by only 43%. The LDL-CE selective uptake was not reduced by the inactivation of LDLr. The activities of the various enzymes involved in cell cholesterol homeostasis were measured in normal and LDLr-deficient cells during incubation in the absence or presence of LDL as a cholesterol source. Essentially, 3-hydroxy-3-methylglutaryl coenzyme A reductase and acyl coenzyme A:cholesterol acyltransferase (ACAT) activities responded to LDL in LDLr-deficient cells as well as in normal HepG2 cells. Inhibition of lysosomal hydrolysis with chloroquine abolished the effect measured on ACAT activity in the presence of LDL, suggesting that CE of LDL, but not free cholesterol, maintains cell cholesterol homeostasis. Thus, in HepG2 cells, when LDLr function is virtually abolished, LDL-CE selective uptake is coupled to cell cholesterol homeostasis. (+info)

Bile acid synthesis in the Smith-Lemli-Opitz syndrome: effects of dehydrocholesterols on cholesterol 7alpha-hydroxylase and 27-hydroxylase activities in rat liver. (8/481)

The Smith-Lemli-Opitz syndrome (SLOS) is a congenital birth defect syndrome caused by a deficiency of 3beta-hydroxysterol Delta(7)-reductase, the final enzyme in the cholesterol biosynthetic pathway. The patients have reduced plasma and tissue cholesterol concentrations with the accumulation of 7-dehydrocholesterol and 8-dehydrocholesterol. Bile acid synthesis is reduced and unnatural cholenoic and cholestenoic acids have been identified in some SLOS patients. To explore the mechanism of the abnormal bile acid production, the activities of key enzymes in classic and alternative bile acid biosynthetic pathways (microsomal cholesterol 7alpha-hydroxylase and mitochondrial sterol 27-hydroxylase) were measured in liver biopsy specimens from two mildly affected SLOS patients. The effects of 7- and 8-dehydrocholesterols on these two enzyme activities were studied by using liver from SLOS model rats that were treated with the Delta(7)-reductase inhibitor (BM15.766) for 4 months and were comparable with more severe SLOS phenotype in plasma and hepatic sterol compositions. In the SLOS patients, cholesterol 7alpha-hydroxylase and sterol 27-hydroxylase were not defective. In BM15.766-treated rats, both enzyme activities were lower than those in control rats and they were competitively inhibited by 7- and 8-dehydrocholesterols. Rat microsomal cholesterol 7alpha-hydroxylase did not transform 7-dehydrocholesterol or 8-dehydrocholesterol into 7alpha-hydroxylated sterols. In contrast, rat mitochondrial sterol 27-hydroxylase catalyzed 27-hydroxylation of 7- and 8-dehydrocholesterols, which were partially converted to 3beta-hydroxycholestadienoic acids. Addition of microsomes to the mitochondrial 27-hydroxylase assay mixture reduced 27-hydroxydehydrocholesterol concentrations, which suggested that 27-hydroxydehydrocholesterols were further metabolized by microsomal enzymes. These results suggest that reduced normal bile acid production is characteristic of severe SLOS phenotype and is caused not only by depletion of hepatic cholesterol but also by competitive inhibition of cholesterol 7alpha-hydroxylase and sterol 27-hydroxylase activities by accumulated 7- and 8-dehydrocholesterols. Unnatural bile acids are synthesized mainly by the alternative pathway via mitochondrial sterol 27-hydroxylase in SLOS. (+info)

There are several types of hypercholesterolemia, including:

1. Familial hypercholesterolemia: This is an inherited condition that causes high levels of low-density lipoprotein (LDL) cholesterol, also known as "bad" cholesterol, in the blood.
2. Non-familial hypercholesterolemia: This type of hypercholesterolemia is not inherited and can be caused by a variety of factors, such as a high-fat diet, lack of exercise, obesity, and certain medical conditions, such as hypothyroidism or polycystic ovary syndrome (PCOS).
3. Mixed hypercholesterolemia: This type of hypercholesterolemia is characterized by high levels of both LDL and high-density lipoprotein (HDL) cholesterol in the blood.

The diagnosis of hypercholesterolemia is typically made based on a physical examination, medical history, and laboratory tests, such as a lipid profile, which measures the levels of different types of cholesterol and triglycerides in the blood. Treatment for hypercholesterolemia usually involves lifestyle changes, such as a healthy diet and regular exercise, and may also include medication, such as statins, to lower cholesterol levels.

There are three main forms of ACH:

1. Classic congenital adrenal hyperplasia (CAH): This is the most common form of ACH, accounting for about 90% of cases. It is caused by mutations in the CYP21 gene, which codes for an enzyme that converts cholesterol into cortisol and aldosterone.
2. Non-classic CAH (NCAH): This form of ACH is less common than classic CAH and is caused by mutations in other genes involved in cortisol and aldosterone production.
3. Mineralocorticoid excess (MOE) or glucocorticoid deficiency (GD): These are rare forms of ACH that are characterized by excessive production of mineralocorticoids (such as aldosterone) or a deficiency of glucocorticoids (such as cortisol).

The symptoms of ACH can vary depending on the specific form of the disorder and the age at which it is diagnosed. In classic CAH, symptoms typically appear in infancy and may include:

* Premature puberty (in girls) or delayed puberty (in boys)
* Abnormal growth patterns
* Distended abdomen
* Fatigue
* Weight gain or obesity
* Easy bruising or bleeding

In NCAH and MOE/GD, symptoms may be less severe or may not appear until later in childhood or adulthood. They may include:

* High blood pressure
* Low blood sugar (hypoglycemia)
* Weight gain or obesity
* Fatigue
* Mood changes

If left untreated, ACH can lead to serious complications, including:

* Adrenal gland insufficiency
* Heart problems
* Bone health problems
* Increased risk of infections
* Mental health issues (such as depression or anxiety)

Treatment for ACH typically involves hormone replacement therapy to restore the balance of hormones in the body. This may involve taking medications such as cortisol, aldosterone, or other hormones to replace those that are deficient or imbalanced. In some cases, surgery may be necessary to remove an adrenal tumor or to correct physical abnormalities.

With proper treatment, many individuals with ACH can lead healthy, active lives. However, it is important for individuals with ACH to work closely with their healthcare providers to manage their condition and prevent complications. This may involve regular check-ups, hormone level monitoring, and lifestyle changes such as a healthy diet and regular exercise.

There are several types of hyperlipidemia, including:

1. High cholesterol: This is the most common type of hyperlipidemia and is characterized by elevated levels of low-density lipoprotein (LDL) cholesterol, also known as "bad" cholesterol.
2. High triglycerides: This type of hyperlipidemia is characterized by elevated levels of triglycerides in the blood. Triglycerides are a type of fat found in the blood that is used for energy.
3. Low high-density lipoprotein (HDL) cholesterol: HDL cholesterol is known as "good" cholesterol because it helps remove excess cholesterol from the bloodstream and transport it to the liver for excretion. Low levels of HDL cholesterol can contribute to hyperlipidemia.

Symptoms of hyperlipidemia may include xanthomas (fatty deposits on the skin), corneal arcus (a cloudy ring around the iris of the eye), and tendon xanthomas (tender lumps under the skin). However, many people with hyperlipidemia have no symptoms at all.

Hyperlipidemia can be diagnosed through a series of blood tests that measure the levels of different types of cholesterol and triglycerides in the blood. Treatment for hyperlipidemia typically involves dietary changes, such as reducing intake of saturated fats and cholesterol, and increasing physical activity. Medications such as statins, fibric acid derivatives, and bile acid sequestrants may also be prescribed to lower cholesterol levels.

In severe cases of hyperlipidemia, atherosclerosis (hardening of the arteries) can occur, which can lead to cardiovascular disease, including heart attacks and strokes. Therefore, it is important to diagnose and treat hyperlipidemia early on to prevent these complications.

There are several types of PKU, including classic PKU, mild PKU, and hyperphenylalaninemia (HPA). Classic PKU is the most severe form of the disorder and is characterized by a complete deficiency of the enzyme phenylalanine hydroxylase (PAH), which is necessary for the breakdown of Phe. Mild PKU is characterized by a partial deficiency of PAH, while HPA is caused by a variety of other genetic defects that affect the breakdown of Phe.

Symptoms of PKU can vary depending on the severity of the disorder, but may include developmental delays, intellectual disability, seizures, and behavioral problems. If left untreated, PKU can lead to serious health complications such as brain damage, seizures, and even death.

The primary treatment for PKU is a strict diet that limits the intake of Phe. This typically involves avoiding foods that are high in Phe, such as meat, fish, eggs, and dairy products, and consuming specialized medical foods that are low in Phe. In some cases, medication may also be prescribed to help manage symptoms.

PKU is an autosomal recessive disorder, which means that it is inherited in an unusual way. Both parents must carry the genetic mutation that causes PKU, and each child has a 25% chance of inheriting the disorder. PKU can be diagnosed through newborn screening, which is typically performed soon after birth. Early diagnosis and treatment can help prevent or minimize the symptoms of PKU and improve quality of life for individuals with the disorder.

Arteriosclerosis can affect any artery in the body, but it is most commonly seen in the arteries of the heart, brain, and legs. It is a common condition that affects millions of people worldwide and is often associated with aging and other factors such as high blood pressure, high cholesterol, diabetes, and smoking.

There are several types of arteriosclerosis, including:

1. Atherosclerosis: This is the most common type of arteriosclerosis and occurs when plaque builds up inside the arteries.
2. Arteriolosclerosis: This type affects the small arteries in the body and can cause decreased blood flow to organs such as the kidneys and brain.
3. Medial sclerosis: This type affects the middle layer of the artery wall and can cause stiffness and narrowing of the arteries.
4. Intimal sclerosis: This type occurs when plaque builds up inside the innermost layer of the artery wall, causing it to become thick and less flexible.

Symptoms of arteriosclerosis can include chest pain, shortness of breath, leg pain or cramping during exercise, and numbness or weakness in the limbs. Treatment for arteriosclerosis may include lifestyle changes such as a healthy diet and regular exercise, as well as medications to lower blood pressure and cholesterol levels. In severe cases, surgery may be necessary to open up or bypass blocked arteries.

Cholelithiasis is a common condition that affects millions of people worldwide. It can occur at any age but is more common in adults over 40 years old. Women are more likely to develop cholelithiasis than men, especially during pregnancy or after childbirth.

The symptoms of cholelithiasis can vary depending on the size and location of the gallstones. Some people may not experience any symptoms at all, while others may have:

* Abdominal pain, especially in the upper right side of the abdomen
* Nausea and vomiting
* Fever
* Shaking or chills
* Loss of appetite
* Yellowing of the skin and eyes (jaundice)

If left untreated, cholelithiasis can lead to complications such as inflammation of the gallbladder (cholangitis), infection of the bile ducts (biliary sepsis), or blockage of the common bile duct. These complications can be life-threatening and require immediate medical attention.

The diagnosis of cholelithiasis is usually made through a combination of imaging tests such as ultrasound, CT scan, or MRI, and blood tests to check for signs of inflammation and liver function. Treatment options for cholelithiasis include:

* Watchful waiting: If the gallstones are small and not causing any symptoms, doctors may recommend monitoring the condition without immediate treatment.
* Medications: Oral medications such as bile salts or ursodiol can dissolve small gallstones and relieve symptoms.
* Laparoscopic cholecystectomy: A minimally invasive surgical procedure to remove the gallbladder through small incisions.
* Open cholecystectomy: An open surgery to remove the gallbladder, usually performed when the gallstones are large or there are other complications.

It is important to seek medical attention if you experience any symptoms of cholelithiasis, as early diagnosis and treatment can help prevent complications and improve outcomes.

The hallmark feature of CTX is the presence of xanthomas, which are fatty deposits that accumulate in the brain and spinal cord. These deposits can cause inflammation and damage to the surrounding tissue, leading to a range of neurological symptoms.

CTX is usually diagnosed through a combination of clinical evaluation, imaging studies such as MRI or CT scans, and laboratory tests to identify the genetic mutations responsible for the condition. There is currently no cure for CTX, but treatment options may include medications to manage seizures and other symptoms, as well as surgery to remove xanthomas in some cases.

There are three main types of Niemann-Pick diseases:

1. Type A: This is the most common and severe form of the disease, and it typically affects infants before the age of one. It is characterized by progressive loss of motor skills, seizures, and death before the age of two.
2. Type B: This form of the disease usually presents in adulthood and is characterized by gradually worsening neurological symptoms, including muscle weakness, ataxia (loss of coordination), and dementia. Life expectancy for individuals with type B Niemann-Pick disease is typically between 20 and 40 years.
3. Type C: This form of the disease is less severe than types A and B and is often diagnosed in childhood or adolescence. It is characterized by a range of symptoms, including developmental delays, learning disabilities, and mild neurological problems.

Niemann-Pick diseases are caused by mutations in the genes that code for proteins involved in lipid metabolism. These proteins play a crucial role in the transport of lipids within cells, particularly in the brain and other organs. Without these proteins, lipids accumulate in cells and cause damage to their membranes and organelles.

There is currently no cure for Niemann-Pick diseases, but researchers are working on developing new treatments that may help alleviate some of the symptoms and slow the progression of the disease. These treatments include enzyme replacement therapy, gene therapy, and small molecule therapies. In addition, clinical trials are underway to evaluate the safety and effectiveness of these new treatments in humans.

In summary, Niemann-Pick diseases are a group of rare and severe genetic disorders that affect the transport of lipids within cells. There is currently no cure for these diseases, but researchers are working on developing new treatments that may help alleviate some of the symptoms and slow the progression of the disease.

Answer: Type A, B, and C Niemann-Pick disease are three forms of a group of rare genetic disorders that affect lipid metabolism, with types A and B being more severe and type C being less severe.

Body weight is an important health indicator, as it can affect an individual's risk for certain medical conditions, such as obesity, diabetes, and cardiovascular disease. Maintaining a healthy body weight is essential for overall health and well-being, and there are many ways to do so, including a balanced diet, regular exercise, and other lifestyle changes.

There are several ways to measure body weight, including:

1. Scale: This is the most common method of measuring body weight, and it involves standing on a scale that displays the individual's weight in kg or lb.
2. Body fat calipers: These are used to measure body fat percentage by pinching the skin at specific points on the body.
3. Skinfold measurements: This method involves measuring the thickness of the skin folds at specific points on the body to estimate body fat percentage.
4. Bioelectrical impedance analysis (BIA): This is a non-invasive method that uses electrical impulses to measure body fat percentage.
5. Dual-energy X-ray absorptiometry (DXA): This is a more accurate method of measuring body composition, including bone density and body fat percentage.

It's important to note that body weight can fluctuate throughout the day due to factors such as water retention, so it's best to measure body weight at the same time each day for the most accurate results. Additionally, it's important to use a reliable scale or measuring tool to ensure accurate measurements.

The most common form of xanthomatosis is called familial hypercholesterolemia, which is caused by a deficiency of low-density lipoprotein (LDL) receptors in the body. This results in high levels of LDL cholesterol in the blood, which can lead to the accumulation of cholesterol and other lipids in the skin, eyes, and other tissues.

Other forms of xanthomatosis include:

* Familial apo A-1 deficiency: This is a rare disorder caused by a deficiency of apolipoprotein A-1 (apoA-1), a protein that plays a critical role in the transportation of triglycerides and cholesterol in the blood.
* familial hyperlipidemia: This is a group of rare genetic disorders that are characterized by high levels of lipids in the blood, including cholesterol and triglycerides.
* Chylomicronemia: This is a rare disorder caused by a deficiency of lipoprotein lipase, an enzyme that breaks down triglycerides in the blood.

The symptoms of xanthomatosis vary depending on the specific form of the condition and the organs affected. They may include:

* Yellowish deposits (xanthomas) on the skin, particularly on the elbows, knees, and buttocks
* Deposits in the eyes (corneal arcus)
* Fatty liver disease
* High levels of cholesterol and triglycerides in the blood
* Abdominal pain
* Weight loss

Treatment for xanthomatosis typically involves managing the underlying genetic disorder, which may involve dietary changes, medication, or other therapies. In some cases, surgery may be necessary to remove affected tissue.

In summary, xanthomatosis is a group of rare genetic disorders that are characterized by deposits of lipids in the skin and other organs. The symptoms and treatment vary depending on the specific form of the condition.

The disease begins with endothelial dysfunction, which allows lipid accumulation in the artery wall. Macrophages take up oxidized lipids and become foam cells, which die and release their contents, including inflammatory cytokines, leading to further inflammation and recruitment of more immune cells.

The atherosclerotic plaque can rupture or ulcerate, leading to the formation of a thrombus that can occlude the blood vessel, causing ischemia or infarction of downstream tissues. This can lead to various cardiovascular diseases such as myocardial infarction (heart attack), stroke, and peripheral artery disease.

Atherosclerosis is a multifactorial disease that is influenced by genetic and environmental factors such as smoking, hypertension, diabetes, high cholesterol levels, and obesity. It is diagnosed by imaging techniques such as angiography, ultrasound, or computed tomography (CT) scans.

Treatment options for atherosclerosis include lifestyle modifications such as smoking cessation, dietary changes, and exercise, as well as medications such as statins, beta blockers, and angiotensin-converting enzyme (ACE) inhibitors. In severe cases, surgical interventions such as bypass surgery or angioplasty may be necessary.

In conclusion, atherosclerosis is a complex and multifactorial disease that affects the arteries and can lead to various cardiovascular diseases. Early detection and treatment can help prevent or slow down its progression, reducing the risk of complications and improving patient outcomes.

The symptoms of SLOS can vary in severity and may include:

1. Developmental delays and intellectual disability
2. Distinctive facial features, such as a prominent forehead, narrow eyes, and a short nose
3. Skeletal abnormalities, including short stature, joint deformities, and scoliosis
4. Heart defects, such as atrial septal defects or ventricular septal defects
5. Kidney problems, such as kidney stones or chronic kidney disease
6. Vision problems, such as cataracts or glaucoma
7. Hearing loss or deafness
8. Increased risk of infections
9. Poor muscle tone and coordination
10. Delayed motor milestones

SLOS is usually diagnosed by a combination of clinical evaluation, laboratory tests, and genetic analysis. Treatment is focused on managing the symptoms and preventing complications. This may include medications to control seizures, physical therapy to improve muscle tone and coordination, and speech and language therapy to address communication difficulties.

The prognosis for individuals with SLOS varies depending on the severity of the mutation and the presence of other health problems. Some individuals with mild forms of the disorder may have a relatively normal life expectancy, while others with more severe forms may have a shorter life span. Early diagnosis and intervention are critical to improving outcomes for individuals with SLOS.

Davis RA, Miyake JH, Hui TY, Spann NJ (Apr 2002). "Regulation of cholesterol-7alpha-hydroxylase: BAREly missing a SHP". Journal ... Li T, Chanda D, Zhang Y, Choi HS, Chiang JY (Apr 2010). "Glucose stimulates cholesterol 7alpha-hydroxylase gene transcription ... Li T, Chanda D, Zhang Y, Choi HS, Chiang JY (Apr 2010). "Glucose stimulates cholesterol 7alpha-hydroxylase gene transcription ... Gbaguidi GF, Agellon LB (2004-01-01). "The inhibition of the human cholesterol 7alpha-hydroxylase gene (CYP7A1) promoter by ...

https://en.wikipedia.org/wiki/Cholesterol_7_alpha-hydroxylase

... or alpha-) methylacyl-CoA racemase (AMACR) deficiency; cholesterol 7 alpha-hydroxylase (CYP7A1) deficiency. The most common ... sterol 27-hydroxylase deficiency (presenting as cerebrotendinous xanthomatosis, CTX); 2- ( ... Cholic acid downregulates cholesterol-7-α-hydroxylase (rate-limiting step in bile acid synthesis), and cholesterol does the ... where it is synthesized from cholesterol. These two major bile acids are roughly equal in concentration in humans. Derivatives ...

https://en.wikipedia.org/wiki/Cholic_acid

Evidence that the enzyme involved is different from cholesterol 7 alpha-hydroxylase". European Journal of Biochemistry. 224 (2 ... 25-hydroxycholesterol+7alpha-hydroxylase at the US National Library of Medicine Medical Subject Headings (MeSH) Portal: Biology ... Li-Hawkins J, Lund EG, Bronson AD, Russell DW (June 2000). "Expression cloning of an oxysterol 7alpha-hydroxylase selective for ... 25-hydroxycholesterol 7alpha-hydroxylase (EC 1.14.13.100, 25-hydroxycholesterol 7alpha-monooxygenase, CYP7B1, CYP7B1 oxysterol ...

https://en.wikipedia.org/wiki/25-hydroxycholesterol_7α-hydroxylase

Boyd GS, Grimwade AM, Lawson ME (1973). "Studies on rat-liver microsomal cholesterol 7alpha-hydroxylase". Eur. J. Biochem. 37 ( ... In enzymology, a cholesterol 7alpha-monooxygenase (EC 1.14.13.17) is an enzyme that catalyzes the chemical reaction cholesterol ... Mitton JR, Scholan NA, Boyd GS (1971). "The oxidation of cholesterol in rat liver sub-cellular particles The cholesterol-7- ... alpha-Hydroxylase enzyme system". Eur. J. Biochem. 20 (4): 569-79. doi:10.1111/j.1432-1033.1971.tb01429.x. PMID 4397276. ...

https://en.wikipedia.org/wiki/Cholesterol_7alpha-monooxygenase

In an animal model, THAP was reported to enhance cholesterol 7 alpha-hydroxylase (CYP7A1) activity. THAP is also used as a ... "Induction of human cholesterol 7α-hydroxylase in HepG2 cells by 2,4,6-trihydroxyacetophenone". European Journal of Pharmacology ... THAP is a chemical precursor that can be used to form part of the backbone of 5,7-dihydroxyflavones like noreugenin, apigenin, ...

https://en.wikipedia.org/wiki/2,4,6-Trihydroxyacetophenone

Lavery, Daniel J.; Schibler, Ueli (1993). "Circadian transcription of the cholesterol 7 alpha hydroxylase gene may involve the ... 7 (10): 1871-84. doi:10.1101/gad.7.10.1871. PMID 8405996. Gorski, K.; Carneiro, M.; Schibler, U. (1986). "Tissue-specific in ...

https://en.wikipedia.org/wiki/NUN_buffer

Its structure was 39% similar to human prostacyclin synthase (CYP8) and 31% similar to cholesterol 7 alpha-hydroxylase (CYP7). ... sterol 12alpha-hydroxylase (ambiguous), and HCO 12alpha-hydroxylase. This enzyme belongs to the family of oxidoreductases, ... 7alpha-hydroxycholest-4-en-3-one 12alpha-hydroxylase (EC 1.14.14.139, previously EC 1.14.13.95) is an enzyme that catalyzes the ... "Molecular cloning and expression of rabbit sterol 12alpha-hydroxylase". The Journal of Biological Chemistry. 271 (50): 32269-75 ...

https://en.wikipedia.org/wiki/7alpha-hydroxycholest-4-en-3-one_12alpha-hydroxylase

Do R, Kiss RS, Gaudet D, Engert JC (January 2009). "Squalene synthase: a critical enzyme in the cholesterol biosynthesis ... Ness GC, Zhao Z, Keller RK (June 1994). "Effect of squalene synthase inhibition on the expression of hepatic cholesterol ... As a squalene synthase inhibitor, zaragozic acid produces lower plasma cholesterol levels in primates. Treatment of rats with ... and cholesterol 7 alpha hydroxylase". Arch. Biochem. Biophys. 311 (2): 277-85. doi:10.1006/abbi.1994.1238. PMID 7911291. ...

https://en.wikipedia.org/wiki/Zaragozic_acid

"A prospero-related homeodomain protein is a novel co-regulator of hepatocyte nuclear factor 4 α that regulates the cholesterol ... is a corepressor of human liver receptor homolog-1 and suppresses the transcription of the cholesterol 7-alpha-hydroxylase gene ... 225 (3): 351-7. doi:10.1002/dvdy.10163. PMID 12412020. Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and ... 7α-hydroxylase gene". J. Biol. Chem. 281 (15): 10081-8. doi:10.1074/jbc.M513420200. PMC 1785292. PMID 16488887. Schneider M, ...

https://en.wikipedia.org/wiki/PROX1

"Correlation of farnesoid X receptor coactivator recruitment and cholesterol 7alpha-hydroxylase gene repression by bile acids". ... Peroxisome proliferator-activated receptor gamma coactivator 1-alpha and Retinoid X receptor alpha. A number of ligands for FXR ... Kalaany NY, Mangelsdorf DJ (2006). "LXRS and FXR: the yin and yang of cholesterol and fat metabolism". Annual Review of ... One of the primary functions of FXR activation is the suppression of cholesterol 7 alpha-hydroxylase (CYP7A1), the rate- ...

https://en.wikipedia.org/wiki/Farnesoid_X_receptor

Minor pathways initiated by 25-hydroxylase in the liver and 24-hydroxylase in the brain also may contribute to bile acid ... In so doing, more endogenous cholesterol is shunted into the production of bile acids, thereby lowering cholesterol levels. The ... termed alpha (α; displayed as a dashed line). All bile acids have a 3-hydroxyl group, derived from the parent molecule, ... The relationship of bile acids to cholesterol saturation in bile and cholesterol precipitation to produce gallstones has been ...

https://en.wikipedia.org/wiki/Bile_acid

... cholesterol side-chain cleavage enzyme MeSH D08.244.453.915.400 - 25-hydroxyvitamin d3 1-alpha-hydroxylase MeSH D08.244.453.915 ... steroid 11-beta-hydroxylase MeSH D08.244.453.915.730 - steroid 12-alpha-hydroxylase MeSH D08.244.453.915.737 - steroid 16-alpha ... steroid 12-alpha-hydroxylase MeSH D08.811.682.690.708.170.915.737 - steroid 16-alpha-hydroxylase MeSH D08.811.682.690.708.170. ... steroid 12-alpha-hydroxylase MeSH D08.811.682.690.708.783.737 - steroid 16-alpha-hydroxylase MeSH D08.811.682.690.708.783.745 ...

https://en.wikipedia.org/wiki/List_of_MeSH_codes_(D08)

... s may be compared to statin drugs, which reduce LDL-cholesterol (LDL-C) and have only limited effects on other lipid ... Fibrates stimulate peroxisome proliferator activated receptor (PPAR) alpha, which controls the expression of gene products that ... In addition, production of Apo A1 and ATP binding cassette A1 is up-regulated, leading to increased reverse cholesterol ... high cholesterol), and are therefore hypolipidemic agents. Fibrates improve atherogenic dyslipidemia characterized by high ...

https://en.wikipedia.org/wiki/Fibrate

... cholesterol side-chain cleavage enzyme MeSH D12.776.422.220.453.915.400 - 25-hydroxyvitamin d3 1-alpha-hydroxylase MeSH D12.776 ... steroid 12-alpha-hydroxylase MeSH D12.776.422.220.453.915.737 - steroid 16-alpha-hydroxylase MeSH D12.776.422.220.453.915.748 ... steroid 17-alpha-hydroxylase MeSH D12.776.422.220.453.915.760 - steroid 21-hydroxylase MeSH D12.776.422.512.380.440 - ... alpha 1-antichymotrypsin MeSH D12.776.377.715.085.085 - alpha 1-antitrypsin MeSH D12.776.377.715.085.100 - alpha-macroglobulins ...

https://en.wikipedia.org/wiki/List_of_MeSH_codes_(D12.776)

Other hydroxylating agents include flavins, alpha-ketoglutarate-dependent hydroxylases, and some diiron hydroxylases. The ... 17α-Hydroxylase Cholesterol 7 alpha-hydroxylase Dopamine β-hydroxylase Phenylalanine hydroxylase Tyrosine hydroxylase One ... multi-subunit enzymes prolyl 4-hydroxylase, prolyl 3-hydroxylase and lysyl 5-hydroxylase, respectively. These reactions require ... In biochemistry, hydroxylation reactions are often facilitated by enzymes called hydroxylases. A C−H bond is converted to an ...

https://en.wikipedia.org/wiki/Hydroxylation

Capyk JK, D'Angelo I, Strynadka NC, Eltis LD (April 2009). "Characterization of 3-ketosteroid 9{alpha}-hydroxylase, a Rieske ... indicates cholesterol side chain and ring degradation occur simultaneously in Mycobacterium tuberculosis". The Journal of ... Capyk JK, Casabon I, Gruninger R, Strynadka NC, Eltis LD (November 2011). "Activity of 3-ketosteroid 9α-hydroxylase (KshAB) ... 3-ketosteroid 9alpha-monooxygenase (EC 1.14.13.142, KshAB, 3-ketosteroid 9alpha-hydroxylase) is an enzyme with systematic name ...

https://en.wikipedia.org/wiki/3-Ketosteroid_9alpha-monooxygenase

Li-Hawkins J, Lund EG, Turley SD, Russell DW (June 2000). "Disruption of the oxysterol 7alpha-hydroxylase gene in mice". J. ... This endoplasmic reticulum membrane protein catalyzes the first reaction in the cholesterol catabolic pathway of extrahepatic ... Wu Z, Martin KO, Javitt NB, Chiang JY (2000). "Structure and functions of human oxysterol 7alpha-hydroxylase cDNAs and gene ... Tang W, Norlin M (2006). "Regulation of steroid hydroxylase CYP7B1 by androgens and estrogens in prostate cancer LNCaP cells". ...

https://en.wikipedia.org/wiki/CYP7B1

... cholestanetriol 26-hydroxylase, sterol 27-hydroxylase, sterol 26-hydroxylase, cholesterol 27-hydroxylase, CYP27A, CYP27A1, and ... 12 alpha,27-tetrol into 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acid". J. Biol. Chem. 268 (15): 11079-85. PMID ... 12alpha-triol 26-hydroxylase, 5beta-cholestane-3alpha,7alpha,12alpha-triol hydroxylase, ... Usui E, Noshiro M, Okuda K (1990). "Molecular cloning of cDNA for vitamin D3 25-hydroxylase from rat liver mitochondria". FEBS ...

https://en.wikipedia.org/wiki/Cholestanetriol_26-monooxygenase

2004). "Mechanisms of cholesterol and sterol regulatory element binding protein regulation of the sterol 12alpha-hydroxylase ... Li Y, Mezei O, Shay NF (2007). "Human and murine hepatic sterol-12-alpha-hydroxylase and other xenobiotic metabolism mRNA are ... CYP8B1 (cytochrome P450, family 8, subfamily B, polypeptide 1) also known as sterol 12-alpha-hydroxylase is a protein which in ... In the intestine these bile acids affect the solubility of cholesterol and other lipids, promoting their absorption. CYP8B1 is ...

https://en.wikipedia.org/wiki/CYP8B1

Hydroxylation in the kidneys of calcifediol to calcitriol by 1-alpha-hydroxylase is tightly regulated: it is stimulated by ... The cholesterol undergoes a four-step process to make 7-dehydrocholesterol, the same compound that is produced in the skin of ... 25-Hydroxyvitamin D3 1-alpha-Hydroxylase, a kidney enzyme that converts calcifediol to calcitriol. Coulston AM, Boushey C, ... Cholesterol is extracted from wool grease and wool wax alcohols obtained from the cleaning of wool after shearing. ...

https://en.wikipedia.org/wiki/Cholecalciferol

... an orphan nuclear receptor that regulates liver-specific expression of the human cholesterol 7alpha-hydroxylase gene". ... developmentally regulated chromatin-hypersensitive domains carrying the alpha 1-fetoprotein gene promoter and the albumin/alpha ... an orphan nuclear receptor that regulates liver-specific expression of the human cholesterol 7alpha-hydroxylase gene". ... LRH-1 plays a critical role in the regulation of development, cholesterol transport, bile acid homeostasis and steroidogenesis ...

https://en.wikipedia.org/wiki/Liver_receptor_homolog-1

X receptor alpha antagonizes the stimulatory effect of their respective ligands on the murine cholesterol 7alpha-hydroxylase ... Liver X receptor alpha (LXR-alpha) is a nuclear receptor protein that in humans is encoded by the NR1H3 gene (nuclear receptor ... "Control of cellular cholesterol efflux by the nuclear oxysterol receptor LXR alpha". Proceedings of the National Academy of ... "PPAR-alpha and PPAR-gamma activators induce cholesterol removal from human macrophage foam cells through stimulation of the ...

https://en.wikipedia.org/wiki/Liver_X_receptor_alpha

Payne AH, Hales DB (Dec 2004). "Overview of steroidogenic enzymes in the pathway from cholesterol to active steroid hormones". ... 25-Hydroxyvitamin D 1-alpha-hydroxylase (VD 1A hydroxylase) also known as calcidiol 1-monooxygenase or cytochrome p450 27B1 ( ... or simply 1-alpha-hydroxylase is a cytochrome P450 enzyme that in humans is encoded by the CYP27B1 gene. VD 1A hydroxylase is ... 25-Hydroxyvitamin+D3+1-alpha-Hydroxylase at the US National Library of Medicine Medical Subject Headings (MeSH) Human CYP27B1 ...

https://en.wikipedia.org/wiki/25-Hydroxyvitamin_D_1-alpha-hydroxylase

... cholesterol) substrates, most of which are not fatty acids. The CYP450 omega hydroxylases are accordingly better viewed as a ... 20-hydroxy EPA and 20-hydroxy-DHA do stimulate Peroxisome proliferator-activated receptor alpha but their range of biological ... CYP450 omega hydroxylases, CYP450 ω-hydroxylases, CYP omega hydroxylase, CYP ω-hydroxylases, fatty acid omega hydroxylases, ... Cytochrome P450 omega hydroxylases, also termed cytochrome P450 ω-hydroxylases, ...

https://en.wikipedia.org/wiki/Cytochrome_P450_omega_hydroxylase

... is produced from cholesterol by hepatic cholesterol 7α-hydroxylase (CYP7A1). It is metabolized by the enzyme 7α-hydroxycholest- ... 4-en-3-one 12α-hydroxylase to 7α,12α-dihydroxycholest-4-en-3-one and then to cholic acid, the major primary bile acid in humans ... "Bile acid synthesis in humans has a rapid diurnal variation that is asynchronous with cholesterol synthesis". Gastroenterology ... Serum 7α-hydroxy-4-cholesten-3-one values vary during the day as bile acid synthetic rates have a diurnal rhythm. Elevated ...

https://en.wikipedia.org/wiki/7α-Hydroxy-4-cholesten-3-one

Calcifediol is subsequently converted by the action of 25-hydroxyvitamin D3 1-alpha-hydroxylase to calcitriol, the active form ... P450 proteins are mono-oxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, ... CYP2R1 is cytochrome P450 2R1, an enzyme which is the principal vitamin D 25-hydroxylase. In humans it is encoded by the CYP2R1 ... CYP2R1 is present in the endoplasmic reticulum of the liver (the microsomal fraction). It has 25-hydroxylase activity, which ...

https://en.wikipedia.org/wiki/CYP2R1

Cholesterol can be synthesized de novo in the adrenal cortex. Yet, the major source of cholesterol appears to be cholesterol ... Zhou M, Gomez-Sanchez CE (July 1993). "Cloning and expression of a rat cytochrome P-450 11 beta-hydroxylase/aldosterone ... 17-alpha-hydroxyprogesterone → (hydroxylation at C21) → 11-Deoxycortisol → (hydroxylation at C11) → Cortisol The adrenal cortex ... London E, Wassif CA, Horvath A, Tatsi C, Angelousi A, Karageorgiadis AS, Porter FD, Stratakis CA (2015). "Cholesterol ...

https://en.wikipedia.org/wiki/Adrenal_cortex

Akhtar MK, Kelly SL, Kaderbhai MA (November 2005). "Cytochrome b(5) modulation of 17{alpha} hydroxylase and 17-20 lyase (CYP17 ... which allows cholesterol to translocate into the mitochondria. Within the mitochondria, cholesterol is converted to ... labeled alpha- and beta- subunits) that are non-covalently associated: The alpha subunits of LH, FSH, TSH, and hCG are ... The gene for the alpha subunit is located on chromosome 6q12.21. The luteinizing hormone beta subunit gene is localized in the ...

https://en.wikipedia.org/wiki/Luteinizing_hormone

21-hydroxylase, 17α-hydroxylase, 11β-hydroxylase and 3β-hydroxysteroid dehydrogenase), lipoid CAH due to deficiency of StAR and ... The subunit ACTH undergoes further cleavage to produce alpha-MSH, the most important MSH for skin pigmentation. In secondary ... To form cortisol, the adrenal gland requires cholesterol, which is then converted biochemically into steroid hormones. ... Autoimmune destruction of the adrenal cortex is caused by an immune reaction against the enzyme 21-hydroxylase (a phenomenon ...

https://en.wikipedia.org/wiki/Addison's_disease

... the inability of prolyl hydroxylases to catalyze reactions results in stabilization of hypoxia-inducible factor alpha, which is ... The cytosolic acetyl-CoA is used for fatty acid synthesis and the production of cholesterol. Cholesterol can, in turn, be used ... Their carbon skeletons (i.e. the de-aminated amino acids) may either enter the citric acid cycle as intermediates (e.g. alpha- ... To turn them into amino acids the alpha keto-acids formed from the citric acid cycle intermediates have to acquire their amino ...

https://en.wikipedia.org/wiki/Citric_acid_cycle

Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency Congenital adrenal hyperplasia due to 17 alpha-hydroxylase ... jaundice renal tubular insufficiency Cholesterol ester storage disease Cholesterol esterification disorder Cholesterol ... deficiency Congenital adrenal hyperplasia due to 21-hydroxylase deficiency Congenital adrenal hyperplasia due to 3 beta- ... monosomy Chromosome 7, partial monosomy 7p Chromosome 7, trisomy 7p Chromosome 7, trisomy 7p13 p12 2 Chromosome 7, trisomy 7q ...

https://en.wikipedia.org/wiki/List_of_diseases_(C)

... cholesterol 27-hydroxylase) inhibitor in vitro. CYP27A1 converts cholesterol into 27-hydroxycholesterol, an oxysterol that has ... 5 alpha-dihydrotestosterone and [3H]cortisol binding to plasma proteins". J. Steroid Biochem. 33 (2): 251-5. doi:10.1016/0022- ... In addition to CYP27A1, bicalutamide has been found to bind to and inhibit CYP46A1 (cholesterol 24-hydroxylase) in vitro, but ... role of 3 alpha- and 3 beta-androstanediols". Biology of Reproduction. 51 (3): 562-71. doi:10.1095/biolreprod51.3.562. PMID ...

https://en.wikipedia.org/wiki/Pharmacology_of_bicalutamide

... which converts cholesterol to pregnenolone, 17α-hydroxylase and 17,20-lyase, which convert pregnenolone into androgens, and 11β ... Defects in the sterol 5-6 desaturase enzyme reduce the toxic effects of azole inhibition of the 14-alpha demethylation step. ... 11β-Hydroxylase inhibitors, 21-Hydroxylase inhibitors, Acetamides, Aldosterone synthase inhibitors, Antifungals for ... It produces this effect through inhibition of 17α-hydroxylase and 17,20-lyase, which are involved in the synthesis and ...

https://en.wikipedia.org/wiki/Ketoconazole

Cholesterol, Protein, and Amino Acids. Washington, DC: The National Academies Press. pp. 589-768. doi:10.17226/10490. ISBN 978- ... is the inability to metabolize phenylalanine because of a lack of the enzyme phenylalanine hydroxylase. Individuals with this ... "Structure-activity relationships of alpha-amino acid ligands for the alpha2delta subunit of voltage-gated calcium channels". ... The corresponding enzymes for those compounds are the aromatic amino acid hydroxylase family and nitric oxide synthase. ...

https://en.wikipedia.org/wiki/Phenylalanine

5-alpha reductase inhibitors (such as finasteride and dutasteride) may also be used; they work by blocking the conversion of ... Furthermore, excessive insulin increases the activity of 17α-hydroxylase, which catalyzes the conversion of progesterone to ... cholesterol and triglycerides. Women with PCOS show a decreased removal of atherosclerosis-inducing remnants, seemingly ... tumour necrosis factor alpha, and interleukin-1 in modulating progesterone and oestradiol production by human luteinized ...

https://en.wikipedia.org/wiki/Polycystic_ovary_syndrome

3-alpha,7-alpha-dihydroxy-5-beta-cholestanate-CoA ligase EC 6.2.1.29: Transferred entry: 6.2.1.7 EC 6.2.1.30: Phenylacetate-CoA ... EC 1.14.16 Phenylalanine hydroxylase EC 1.14.16.1 Category:EC 1.14.18 Tyrosinase EC 1.14.18.1 Category:EC 1.15.1 Superoxide ... homocysteine hydrolase Alkenylglycerophosphocholine hydrolase Alkenylglycerophosphoethanolamine hydrolase Cholesterol-5,6-oxide ... EC 1.6.7 now Category:EC 1.18.1 Category:EC 1.6.8 now Category:EC 1.5.1 Category:EC 1.6.99 (with other acceptors) Category:EC ...

https://en.wikipedia.org/wiki/List_of_enzymes

Sharquie KE, Noaimi AA, Saleh BO, Anbar ZN (December 2009). "The frequency of 21-alpha hydroxylase enzyme deficiency and ... The cytochrome P450 enzymes catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and ... 21-hydroxylase is essential for the biosynthesis of cortisol and aldosterone. 21-hydroxylase, as a member of the cytochrome ... Steroid 21-hydroxylase (also known as steroid 21-monooxygenase, cytochrome P450C21, 21α-hydroxylase and less commonly 21β- ...

https://en.wikipedia.org/wiki/21-Hydroxylase

In macaques, alpha males have twice the level of serotonin in the brain as subordinate males and females (measured by the ... Hahn P (July 1984). "Effect of litter size on plasma cholesterol and insulin and some liver and adipose tissue enzymes in adult ... June 2007). "Tryptophan hydroxylase-2 gene variation influences personality traits and disorders related to emotional ... December 2003). "Serotonylation of small GTPases is a signal transduction pathway that triggers platelet alpha-granule release ...

https://en.wikipedia.org/wiki/Serotonin

Ikeda S, Tohyama T, Yoshimura H, Hamamura K, Abe K, Yamashita K (February 2003). "Dietary alpha-tocopherol decreases alpha- ... The biological significance of tocotrienols was clearly delineated in the early 1980s, when its ability to lower cholesterol ... "Influence of major structural features of tocopherols and tocotrienols on their omega-oxidation by tocopherol-omega-hydroxylase ... The vitamin E family comprise four tocotrienols (alpha, beta, gamma, delta) and four tocopherols (alpha, beta, gamma, delta). ...

https://en.wikipedia.org/wiki/Tocotrienol

CYP17A1, the cytochrome P450 gene that encodes 17α-hydroxylase and 17,20-lyase, is expressed mainly in the gonads (ovaries and ... Effects of natural and synthetic hormones on subfractions of HDL cholesterol and liver proteins". Acta Obstet Gynecol Scand ... 17-alpha hydroxyprogesterone caproate, and related progestins". Am. J. Obstet. Gynecol. 197 (6): 599.e1-7. doi:10.1016/j.ajog. ... In contrast, oral micronized progesterone does not mitigate against increased HDL-cholesterol levels. Woods KS, Reyna R, Azziz ...

https://en.wikipedia.org/wiki/Pharmacodynamics_of_progesterone

... prolyl hydroxylases and collagen prolyl-4-hydroxylases, through competitive inhibition. 2-oxoglutarate-dependent dioxygenases ... The GABA shunt serves as an alternate route to convert alpha-ketoglutarate into succinate, bypassing the TCA cycle intermediate ... cholesterol, and heme, rely on the temporary formation of succinate. The intermediate is made available for biosynthetic ... In humans, three HIF prolyl 4-hydroxylases regulate the stability of HIFs. Hydroxylation of two prolyl residues in HIF1α ...

https://en.wikipedia.org/wiki/Succinic_acid

In the citric acid cycle, all the intermediates (e.g. citrate, iso-citrate, alpha-ketoglutarate, succinate, fumarate, malate ... These enzymes include monoamine oxidase, rotenone-insensitive NADH-cytochrome c-reductase, kynurenine hydroxylase and fatty ... ceramide and cholesterol metabolism, and glycosphingolipid anabolism. Such trafficking capacity depends on the MAM, which has ... Alvarez-Delgado C, Mendoza-Rodríguez CA, Picazo O, Cerbón M (August 2010). "Different expression of alpha and beta ...

https://en.wikipedia.org/wiki/Mitochondrion

... lowers serum cholesterol and alters distributions of cholesterol in lipoproteins in baboons". Proc. Natl. Acad. Sci. U.S.A. 79 ... Metabolism of 5 alpha-cholest-8(14)-en-3 beta-ol-15-one after intravenous administration to bile duct-cannulated rats". J. Biol ... 17α-Hydroxylase/17,20-lyase (CYP17A1) inhibitors such as abiraterone acetate, etomidate, galeterone, ketoconazole, and ... and thereby inhibit cholesterol production. They notably do not significantly lower circulating levels of cholesterol however, ...

https://en.wikipedia.org/wiki/Steroidogenesis_inhibitor

Zuber MX, Simpson ER, Waterman MR (December 1986). "Expression of bovine 17 alpha-hydroxylase cytochrome P-450 cDNA in ... The first step in the biosynthesis involves the oxidative cleavage of the side-chain of cholesterol by cholesterol side-chain ... It is biosynthesized in several steps from cholesterol and is converted in the liver to inactive metabolites. It exerts its ... In the next step, two additional carbon atoms are removed by the CYP17A1 (17α-hydroxylase/17,20-lyase) enzyme in the ...

https://en.wikipedia.org/wiki/Testosterone

While cholesterol is essential for membranes and steroid hormones, excess cholesterol affects blood flow impairing cognitive ... Autoantibodies against folate receptor alpha have been found in up to 75% of children with autism. Folate deficiency most ... "Distribution of the vitamin D receptor and 1α-hydroxylase in human brain". Journal of Chemical Neuroanatomy. 29 (1): 21-30. doi ... Niacin is also involved in the synthesis of fatty acids and cholesterol, which are known mediators of brain biochemistry, and ...

https://en.wikipedia.org/wiki/Nutritional_neuroscience

... the transport of cholesterol into the mitochondria and the conversion of cholesterol to pregnenolone-the first step in the ... Combined 17α-hydroxylase/17,20-lyase deficiency - A condition in which presents as a combination of the symptoms of congenital ... An autosomal recessive condition caused by a mutation of the 5-alpha reductase type 2 gene. It only affects people with Y ... 14 (7): 415-429. doi:10.1038/s41574-018-0010-8. PMC 7136158. PMID 29769693. Zderic SA, Canning DA, Carr MC, Snyder III HM, eds ...

https://en.wikipedia.org/wiki/Disorders_of_sex_development

... which induce or repress transcription of the pathways rate-limiting enzyme cholesterol 7alpha-hydroxylase (CYP7A1). The ... The catabolism of cholesterol into bile acids is regulated by oxysterols and bile acids, ... which induce or repress transcription of the pathways rate-limiting enzyme cholesterol 7alpha-hydroxylase (CYP7A1). The ... The catabolism of cholesterol into bile acids is regulated by oxysterols and bile acids, ...

https://pubmed.ncbi.nlm.nih.gov/11030331/?dopt=Abstract

Peroxisome proliferator-activated receptor alpha (PPARalpha) and agonist inhibit cholesterol 7alpha-hydroxylase gene (CYP7A1) ... Linkage between cholesterol 7alpha-hydroxylase and high plasma low-density lipoprotein cholesterol concentrations. Wang, J., ... In the liver, the liver X receptor alpha induces the cholesterol 7alpha-hydroxylase (CYP7A1) gene, which controls the rate- ... Regulation of cholesterol-7alpha-hydroxylase: BAREly missing a SHP. Davis, R.A., Miyake, J.H., Hui, T.Y., Spann, N.J. J. Lipid ...

https://www.wikigenes.org/e/gene/e/1581.html

The abnormal buildup of cholesterol in the brain probably also contributes to the death of nerve cells. The loss of these cells ... In the brain, a decrease in enzyme activity results in an accumulation of cholesterol and alters neurosteroid production ... Sequence alterations within CYP7B1 implicate defective cholesterol homeostasis in motor-neuron degeneration. Am J Hum Genet. ... Oxysterol 7-alpha-hydroxylase helps maintain normal cholesterol levels in the brain and, by producing neurosteroids through ...

https://medlineplus.gov/genetics/condition/spastic-paraplegia-type-5a/

Serum cystatin C, lipids [total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides], and ... Fasting blood samples were taken from the cubital vein with the participants in the supine position between 7:00 am and 12:00 ... 7). Profiling of urine samples using proton nuclear magnetic resonance (NMR) spectroscopy among large cohorts (8, 9) ... 3). Those included classic parameters (e.g., total cholesterol or LDL cholesterol and HDL cholesterol) and more specific ...

https://www.deepdyve.com/lp/ou_press/comprehensive-metabolic-profiling-reveals-a-lipid-rich-fingerprint-of-72AqmdoPb7

Steroid 11-beta-Hydroxylase D8.811.682.690.708.783.750 Steroid 12-alpha-Hydroxylase D8.811.682.690.708.783.730 Steroid 16-alpha ... Cholesterol Side-Chain Cleavage Enzyme D8.811.682.690.708.783.212 Cholesterol, Dietary D4.808.247.808.197.225 Cholesterol, HDL ... Hydroxylase D8.811.682.690.708.783.737 Steroid 17-alpha-Hydroxylase D8.811.682.690.708.783.745 Steroid 21-Hydroxylase D8.811. ... alpha 1-Antichymotrypsin D12.644.822.750.30 D12.776.645.750.30 alpha 1-Antitrypsin D12.644.822.750.35 D12.776.645.750.35 alpha- ...

https://decs.bvs.br/P/mnchg2016.txt

Cholesterol side-chain cleavage enzyme * 25-Hydroxyvitamine D3 1-alpha-hydroxylase [D08.811.682.690.708.170.915.400] ... Cholesterol 7-alpha-hydroxylase Synonymes. CYP 7A CYP7A Cholesterol 7-alpha-monooxygenase Cytochrome P-450 CYP7A Cytochrome ... Cholesterol 7-alpha-hydroxylase - Concept préféré Concept UI. M0004276. Terme préféré. ... Cholesterol 7-alpha-monooxygenase. Cytochrome P-450 CYP7A. Cytochrome P450 7A. Code(s) darborescence:. D08.244.453.890.500. ...

https://decs.bvsalud.org/fr/ths/resource/?id=23193

The gene for cholesterol 7alpha-hydroxylase (CYP7A1) contains a sequence at nt -149 to -118 that was found to play a large role ... Tags: 13-dienoic Acid/*antagonists & inhibitors/pharmacology, 15-Hydroxy-11 alpha, 2017, 9 alpha-(epoxymethano)prosta-5, Andrei ... Glucose stimulates cholesterol 7alpha-hydroxylase gene transcription in human hepatocytes.. Bile acids play important roles in ... Cholesterol 7alpha-hydroxylase gene (CYP7A1) transcription is repressed by bile acids. The goal of this study is to elucidate ...

https://neomed.omeka.net/items/browse?tags=Cultured

Wang, J., Freeman, D. J., Grundy, S. M., Levine, D. M., Guerra, R., & Cohen, J. C. (1998). Linkage between cholesterol 7α- ... hydroxylase and high plasma low-density lipoprotein cholesterol concentrations. Journal of Clinical Investigation, 101(6), 1283 ... Wang, J, Freeman, DJ, Grundy, SM, Levine, DM, Guerra, R & Cohen, JC 1998, Linkage between cholesterol 7α-hydroxylase and high ... Linkage between cholesterol 7α-hydroxylase and high plasma low-density lipoprotein cholesterol concentrations. In: Journal of ...

https://utsouthwestern.elsevierpure.com/en/publications/linkage-between-cholesterol-7

The 100% ethanol extract of mulberry root bark resulted in the highest inhibition of cholesterol synthesis (−95%, P. P. P. P. ... The 100% ethanol extract of mulberry root bark resulted in the highest inhibition of cholesterol synthesis (−95%, P. P. P. P. ... In addition, hepatic cholesterol regulations were examined through LDL uptake assay (C) and real-time PCR in extract stimulated ... In addition, hepatic cholesterol regulations were examined through LDL uptake assay (C) and real-time PCR in extract stimulated ...

https://www.e-jkfn.org/journal/view.html?volume=51&number=7&spage=633

The levels of cholesterol 7 alpha-hydroxylase, the rate-limiting enzyme of BA synthesis, were not changed. Notably, the ... The P3A(+) transcript encodes a non-functional alpha subunit that comprises 50% of the transcripts in normal human skeletal ... A of CHRNA1 that encodes the muscle nicotinic acetylcholine receptor alpha subunit disrupts binding of a splicing repressor, ... 7. Hepatic IRS1 and ß-catenin expression is associated with histological progression and overt diabetes emergence in NAFLD ...

https://pesquisa.bvsalud.org/controlecancer/?lang=pt&q=au:Okushin,+Kazuya

Feingold, K.R., Spady, D.K., Pollock, A.S., Moser, A.H., Grunfeld, C. (1996). Endotoxin, TNF, and IL-1 decrease cholesterol 7 ... alpha-hydroxylase mRNA levels and activity. J. Lipid Res. 37, 223-228. ... role of FXR-regulated organic solute transporter-alpha/beta in the adaptive response to bile acids. J. Physiol. Gastrointest. ... 87, 7-11. Ankley, G.T., Bennett, R.S., Erickson, R.J., Hoff, D.J., Hornung, M.W., Johnson, R.D., Mount, D.R., Nichols, J.W., ...

https://aopwiki.org/aops/27

... high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),alanine aminotransferase(ALT),and ... in cholestasis rats induced by alpha-naphthalene isothiocyanate (ANIT). Methods: Fifty SD rats were randomly divided into five ... After the last administration, serum total cholesterol (TC), triglyceride (TG) and total bile acids (TBA) were measured. The ... The mRNA transcription levels of SHP and cholesterol 7 alpha hydroxylase (CYP7A1) in RPH were detected by real-time-PCR, and ...

https://search.bvsalud.org/gim/?lang=en&q=mh:%22Iridoid%20Glucosides%22

https://decs2018.bvsalud.org/P/mnchg2016.txt

Steroid 12-alpha-Hydroxylase D8.244.453.900.500 D8.811.682.690.708.170.900.500 D12.776.422.220.453.900.500 Steroid 17-alpha- ... Cholesterol, Dietary D4.808.247.808.197.225 D4.210.500.247.808.197.225 Cholesterol, HDL D4.808.247.808.197.238 D4.210.500.247. ... 25-Hydroxyvitamin D3 1-alpha-Hydroxylase D8.244.453.499.500 D8.811.682.690.708.170.493.500 D12.776.422.220.453.499.500 2H-Benzo ... alpha-Defensins D12.644.276.87.44 D12.776.467.87.125 D23.529.87.48 alpha-Endorphin D12.776.641.650.405.935.119 D12.776.631.650. ...

https://decs2017.bvsalud.org/P/mnchg2017.txt

https://decs2016.bvsalud.org/P/mnchg2016.txt

Cholesterol transport and Ion homeostasis. A comparative analysis of vit C-mediated modulation of gene expression data in ... PPAR-alpha and PPAR-gamma activators induce cholesterol removal from human macrophage foam cells through stimulation of the ... Investigating the dependence of the hypoxia-inducible factor hydroxylases (factor inhibiting HIF and prolyl hydroxylase domain ... Another interesting class where vit C exerted its effect was Cholesterol transport. The association between cholesterol ...

https://bmcgenomics.biomedcentral.com/articles/10.1186/s12864-017-3635-4

The levels of intracellular total cholesterol (TC), free cholesterol (FC), cholesterol ester (EC), total bile acids (TBA) and ... Few in vitro studies are concerned the concentration change of cholesterol and its product of bile acids, and the molecular ... enhance CYP7A1 expression by inducing HNF4α and inhibiting MEK1/2 and p-c-Jun expressions to promote intracellular cholesterol ... A number of studies indicate that taurine promotes cholesterol conversion to bile acids by upregulating CYP7A1 gene expression ...

https://lipidworld.biomedcentral.com/articles/10.1186/s12944-017-0444-3

Of these five enzymes, three (ie, 20-alpha hydroxylase, 3-beta-hydroxysteroid dehydrogenase, and 17-alpha hydroxylase) are ... Production of testosterone from cholesterol involves five enzymatic steps, and defects have been identified at each step. ... Genetic counseling is desirable because 17-alpha hydroxylase and 3-beta-hydroxysteroid dehydrogenase deficiencies are ... Martin David Bomalaski, MD, FAAP is a member of the following medical societies: Alpha Omega Alpha, American Academy of ...

http://emedicine.medscape.com/article/1015520-overview

... supporting the potential role of Parasutterella in bile acid maintenance and cholesterol metabolism. The successful ... Bottom right: serum cholesterol concentration of the CON and PARA mice. For all treatment group, n = 8. Data are shown as mean ... For all treatment groups, n = 8. b Alpha-diversity analysis of bacterial communities in ileal, cecal, and colonic contents of ... The Cyp7a1 expression has been correlated with decreased serum cholesterol in human and mouse studies [32, 33], accordingly, ...

https://www.nature.com/articles/s41396-019-0364-5?error=cookies_not_supported&code=8e219942-8042-49f6-ad8d-cabda877bd40

Tyrosine hydroxylase TH01 9.3 allele in the occurrence of sudden infant death syndrome in Swiss Caucasians. Journal of forensic ... Alpha-particle carcinogenesis in Thorotrast patients: epidemiology, dosimetry, pathology, and molecular analysis. Journal of ... Polymorphism 1936A , G in the AKAP10 gene (encoding A-kinase-anchoring protein 10) is associated with higher cholesterol cord ... VNTR polymorphism of tyrosine hydroxylase gene and schizophrenia in the Korean population. Neuropsychobiology 2003 47 (3): 131- ...

https://phgkb.cdc.gov/PHGKB/searchSummary.action?firstQuery=Syndrome+and+TH&Mysubmit=Search

cholesterol 24-hydroxylase. 1.14.14.26. 24-hydroxycholesterol 7alpha-hydroxylase. 1.14.14.27. resorcinol 4-hydroxylase (FADH2) ... ent-cassa-12,15-diene 11-hydroxylase. 1.14.14.113. alpha-humulene 10-hydroxylase. ... 4-amino-L-phenylalanyl-[CmlP-peptidyl-carrier-protein] 3-hydroxylase. 1.14.99.66. [histone-H3]-N(6),N(6)-dimethyl-L-lysine(4) ... tRNA(Phe) (7-(3-amino-3-carboxypropyl)wyosine(37)-C(2))-hydroxylase. ...

https://enzyme.expasy.org/EC/1.14.-.-

Regulation of cholesterol 7alpha-hydroxylase mRNA expression in C57BL/6 mice fed an atherogenic diet. 178巻 2号 265-269頁 2005 原著論 ... Cross talk of tumor necrosis factor-alpha and the renin-angiotensin system in tumor necrosis factor-alpha-induced plasminogen ... Possible role of alpha-cell insulin resistance in exaggerated glucagon responses to arginine in type 2 diabetes N Tsuchiyama, T ... Blocking TNF-alpha in mice reduces colorectal carcinogenesis associated with chronic colitis BK Popivanova, K Kitamura, Y Wu, T ...

http://ridb.kanazawa-u.ac.jp/public/detail.php?kaken=60185923

Hyperphosphatemia inhibits 1-alpha hydroxylase in the proximal tubule directly and indirectly through stimulation of FGF23, ... Tonelli M, Sacks F, Pfeffer M, Gao Z, Curhan G, Cholesterol and Recurrent Events Trial Investigators. Relation between serum ... Hyperphosphatemia inhibits 1-alpha hydroxylase in the proximal tubule directly and indirectly through stimulation of FGF23, ... High phosphate levels also inhibit 1-alpha hydroxylase, a renal enzyme that produces active vitamin D by adding a hydroxyl ...

https://www.medscape.com/answers/241185-70922/what-is-the-role-of-urinary-phosphate-measurement-in-the-evaluation-of-hyperphosphatemia

11-Beta-Hydroxylase. 721. 98. 0.01. -0.93. 0.14. 0.61. Steroid 5-Alpha-Reductase. 293. Target. Target. 11-Beta-Hydroxylase. 721 ... Cholesterol. 182,390. Disease. Target. ... 11-Beta-Hydroxylase. 721. 1. 0.00. -1.00. 0.00. 0.53. Collagen ... 11-Beta-Hydroxylase. 721. 1. 0.00. -1.00. 0.00. 0.54. EGF 27,487. Target. Target. 11-Beta-Hydroxylase. 721. 1. 0.00. -1.00. ... 11-Beta-Hydroxylase. 721. 3. 0.00. -1.00. 0.00. 0.53. APOE 12,771. Target. Target. 11-Beta-Hydroxylase. 721. 1. 0.00. -1.00. ...

https://gramener.com/pharmatextanalysis/subtable/?pf%3Arows=50&pf%3Asort=WORD2&pf%3Asort=-WORD2&pf%3Asort=C_CENT&pf%3Asort=OVERLP&pf%3Asort=OVERLP&pf%3Asort=WORD2&pf%3Asort=OVERLP&pf%3Apage=0

alpha-amanitin inhibits poly II Start and Stop Codons Start. AUG (Are U Going?). Stop. UGA (U Go Away). UAA (U Are Away). UAG ( ... hepatic cholesterol to periphery. uptake via R-med endocytosis (Apo B100). excess causes ATH, xanthomas. Bad for you HDL ... phenylalanine hydroxylase deficiency. tetrahydrobiopterin cofactor deficiency. tyrosine becomes essential. mental retardation. ... Increased Cholesterol/LDL. Auto Dom defect in LDL R. xanthomas. MI before 30y in homozygous pt Familial Hypertriglyceridemia ...

https://cueflash.com/decks/tag/acousticnelson11/tag/medicine/54401/First_Aid:_Biochemistry

Zhang, X., Beaulieu, J. M., Sotnikova, T. D., Gainetdinov, R. R., and Caron, M. G. (2004) Tryptophan hydroxylase-2 controls ... Initially, the levels of interleukins, tumor necrosis factor alpha, and interferon are increased in both conditions while ... Wassal SR and Stillwell W (2009). Polyunsaturated fatty acid-cholesterol interactions: domain formation in membranes. Biochim. ... Tryptophan hydroxylase Dopa Decarboxylase. Tryptophan -----, 5-Hydroxytryptophan ----, Serotonin. (5-HTP) (5-HT, 5 - ...

https://brainfoodbrainfood.com/tag/paxil/

Once formed, 25 D3 is more activated by the mitochondrial 1 hydroxylase to produce 1,25 dihydroxyvitamin (-)-MK 801 D3 2D3, the ... In the acidic bile acid pathway, CYP27A1 is responsible for the rate limiting action of 26 hydroxylation of cholesterol ... Gene expression In line with this declaration, the particular system A transporter substrate, alpha amino butyric acid, is ... Within the neutral bile acid pathway, CYP27A1 serves to hydroxylate bile acid intermediates, 5B cholestane 3,7,12 triol and 5B ...

https://mirna21.com/2013/07

Cholesterol 25-hydroxylase) (Cytochrome P-450MP) (Cytochrome P450 MP-4) (Cytochrome P450 MP-8) (Cytochrome P450 PB-1) (S- ... Statins can effectively lower low-density lipoprotein cholesterol levels and lessen the risk of CVD for this population. ... Liver microsomal testosterone 6beta-hydroxylase (CYP3A4) activity was slightly greater in females than males, but the ... mephenytoin 4-hydroxylase) [CYP2C10] Publications[править]. Pediatric Cytochrome P450 Activity Alterations in Nonalcoholic ...

https://transhumanist.ru/CYP2C9

20. Genomic cloning, sequencing, and analysis of the hamster cholesterol 7 alpha-hydroxylase gene (CYP7). (nih.gov)
This enzyme, encoded by CYP7 , converts cholesterol to 7-alpha-hydroxycholesterol which is the first and rate-limiting step in the synthesis of BILE ACIDS . (nih.gov)
Esta enzima, codificada por CYP7, convierte el colesterol en 7-alfa-hidroxicolesterol, que es el paso primero y limitante de la síntesis de los ÁCIDOS Y SALES BILIARES. (bvsalud.org)
In this study we investigated the relationship between plasma LDL-C concentrations and three genes with pivotal roles in LDL metabolism: the low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and cholesterol 7α-hydroxylase (CYP7). (elsevierpure.com)
Hormonal regulation of the cholesterol 7 alpha-hydroxylase gene (CYP7). (omeka.net)
The transcriptional regulation of the rat cholesterol 7 alpha-hydroxylase gene (CYP7) by hormones and signal transduction pathways was studied by transient transfection assay of the promoter activity. (omeka.net)

Transcriptional activation of the cholesterol 7alpha-hydroxylase gene (CYP7A) by nuclear hormone receptors. (omeka.net)
The gene encoding cholesterol 7alpha-hydroxylase (CYP7A), the rate-limiting enzyme in bile acid synthesis, is transcriptionally regulated by bile acids and hormones. (omeka.net)
Key regulator of cholesterol 7-alpha-hydroxylase gene (CYP7A) expression in liver. (nih.gov)

The catabolism of cholesterol into bile acids is regulated by oxysterols and bile acids, which induce or repress transcription of the pathway's rate-limiting enzyme cholesterol 7alpha-hydroxylase (CYP7A1). (nih.gov)
HNF4 and COUP-TFII interact to modulate transcription of the cholesterol 7alpha-hydroxylase gene (CYP7A1). (omeka.net)
The gene for cholesterol 7alpha-hydroxylase (CYP7A1) contains a sequence at nt -149 to -118 that was found to play a large role in determining the overall transcriptional activity and regulation of the promoter. (omeka.net)
Regulation of cholesterol 7alpha-hydroxylase gene (CYP7A1) transcription by the liver orphan receptor (LXRalpha). (omeka.net)
The cholesterol 7alpha-hydroxylase gene (CYP7A1) plays an important role in regulation of bile acid biosynthesis and cholesterol homeostasis. (omeka.net)
Farnesoid X receptor responds to bile acids and represses cholesterol 7alpha-hydroxylase gene (CYP7A1) transcription. (omeka.net)
Cholesterol 7alpha-hydroxylase gene (CYP7A1) transcription is repressed by bile acids. (omeka.net)
Nuclear receptor-mediated repression of human cholesterol 7alpha-hydroxylase gene transcription by bile acids. (omeka.net)
Hydrophobic bile acids strongly repressed transcription of the human cholesterol 7alpha-hydroxylase gene (CYP7A1) in the bile acid biosynthetic pathway in the liver. (omeka.net)

This gene provides instructions for making an enzyme called oxysterol 7-alpha-hydroxylase. (medlineplus.gov)
In the brain, oxysterol 7-alpha-hydroxylase is involved in a pathway that converts cholesterol to hormones called neurosteroids. (medlineplus.gov)
Oxysterol 7-alpha-hydroxylase helps maintain normal cholesterol levels in the brain and, by producing neurosteroids through altering existing hormones within the pathway, regulates the effects of neurosteroids on the brain. (medlineplus.gov)
CYP7B1 gene mutations that cause spastic paraplegia type 5A reduce or eliminate the activity of oxysterol 7-alpha-hydroxylase. (medlineplus.gov)
In the brain, a decrease in enzyme activity results in an accumulation of cholesterol and alters neurosteroid production triggered by oxysterol 7-alpha-hydroxylase. (medlineplus.gov)
In the liver, oxysterol 7-alpha-hydroxylase is involved in the pathway that breaks down a waxy, fat-like substance called cholesterol to form a bile acid called chenodeoxycholic acid. (nih.gov)
Most CYP7B1 gene mutations change single protein building blocks (amino acids) in the oxysterol 7-alpha-hydroxylase enzyme. (nih.gov)
Reduced oxysterol 7-alpha-hydroxylase enzyme activity does not seem to affect cholesterol breakdown or bile acid production in the liver. (nih.gov)
Another pathway in the liver can perform these functions, which may explain why reduction of oxysterol 7-alpha-hydroxylase activity does not impact liver function. (nih.gov)
Transcriptional regulation of human oxysterol 7 alpha-hydroxylase gene (CYP7B1) by Sp1. (omeka.net)
Oxysterol 7 alpha-hydroxylase catalyzes hydroxylation of oxysterols and neurosterols and plays a role in the alternative bile acid synthesis pathway. (omeka.net)
Together with the oxysterol receptors NR1H3/LXR-alpha and NR1H2/LXR-beta, acts as an essential transcriptional regulator of lipid metabolism. (nih.gov)

Contributes to the transcriptional repression of cholesterol 7-alpha-hydroxylase (CYP7A1), the rate-limiting enzyme in bile acid synthesis. (nih.gov)
A number of studies indicate that taurine promotes cholesterol conversion to bile acids by upregulating CYP7A1 gene expression. (biomedcentral.com)
Few in vitro studies are concerned the concentration change of cholesterol and its product of bile acids, and the molecular mechanism of CYP7A1 induction by taurine. (biomedcentral.com)
Taurine could enhance CYP7A1 expression by inducing HNF4α and inhibiting MEK1/2 and p-c-Jun expressions to promote intracellular cholesterol metabolism. (biomedcentral.com)
Cholesterol 7α-hydroxylase (CYP7A1), the rate-limiting enzyme in the major bile acids synthetic pathway, is widely reported to be regulated by several nuclear receptors at the level of gene transcription [ 8 - 10 ]. (biomedcentral.com)
The in vitro studies have focused on the upregulating-effect of taurine on CYP7A1 mRNA level, but the regulatory mechanism and the changes of cellular bile acids, the products of cholesterol degradation, have not been discussed. (biomedcentral.com)
reported that taurine almost did not alter the mRNA levels of LXRα, LRH-1, FXR and SHP-1 of mice with high cholesterol or cholesterol/sodium cholate diets, although CYP7A1 mRNA level was significantly decreased by cholesterol/sodium cholate diet and then two-fold increased by taurine supplementation [ 18 ]. (biomedcentral.com)
Their results suggested that FXR was indeed activated by cholesterol/sodium cholate diet and then functioned as a down-regulator to CYP7A1 in spite of no change of mRNA level, and that taurine might stimulate CYP7A1 expression not by repressing FXR-dependent pathway but by FXR-independent pathway. (biomedcentral.com)
In the present study, HepG2 cell line derived from human hepatoma cell was used to investigate the dose- and time-dependent effects of taurine with a focus on the change of CYP7A1 expression and the concentration of cholesterol and bile acids. (biomedcentral.com)

7. Structure and expression of the Kas12 gene encoding a beta-ketoacyl-acyl carrier protein synthase I isozyme from barley. (nih.gov)
16. Human alpha 2(VI) collagen gene. (nih.gov)
Regulation of human sterol 27-hydroxylase gene (CYP27A1) by bile acids and hepatocyte nuclear factor 4alpha (HNF4alpha). (omeka.net)
Publication: Quantile-Dependent Expressivity and Gene-Lifestyle Interactions Involving High-Density Lipoprotein Cholesterol. (nih.gov)
Key Message: Quantile-dependent expressivity provides a potential explanation for some reported gene-lifestyle interactions for HDL-cholesterol. (nih.gov)

Metyrapone, an inhibitor of 11 beta-hydroxylase, and SC 12937 and AY 9944, inhibitors of cholesterol synthesis, did not prevent ovulation or the progesterone rise induced by exogenous LH. (lookformedical.com)

The effects of the two sequestrants on faecal bile acid excretion, plasma total cholesterol, VLDL + LDL and HDL cholesterol and triglyceride concentrations and on liver enzymes involved in the synthesis and metabolism of cholesterol were investigated in normocholesterolaemic hamsters. (nih.gov)
Mitochondrial sterol 27-hydroxylase (CYP27A1) catalyses sterol side-chain oxidation of bile acid synthesis from cholesterol, and the first reaction of the acidic bile acid biosynthetic pathway. (omeka.net)
Nuclear receptor that acts as a key metabolic sensor by regulating the expression of genes involved in bile acid synthesis, cholesterol homeostasis and triglyceride synthesis. (nih.gov)
Chenodiol suppresses hepatic synthesis of both cholesterol and cholic acid, gradually replacing the latter and its metabolite, deoxycholic acid in an expanded bile acid pool. (illumina.com)
The impacted bile acid profile was consistent with altered expression of ileal bile acid transporter genes and hepatic bile acid synthesis genes, supporting the potential role of Parasutterella in bile acid maintenance and cholesterol metabolism. (nature.com)

The enzyme primarily converts the neurosteroid dehydroepiandrosterone (DHEA) into 7-hydroxy-DHEA. (nih.gov)
A membrane-bound cytochrome P450 enzyme that catalyzes the 7-alpha-hydroxylation of CHOLESTEROL in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE . (nih.gov)
Vitamin C is required for lysyl hydroxylase, an enzyme responsible for attaching the lysine residues together on adjacent collagen strands. (jeffreydachmd.com)
Above image shows three steps in attachment of two fibrils (collagen strands) by combining two lysine molecules with the help of an enzyme lysine hydroxylase which requires vitamin C. (jeffreydachmd.com)

The levels of intracellular total cholesterol (TC), free cholesterol (FC), cholesterol ester (EC), total bile acids (TBA) and medium TBA were determined after HepG2 cells were cultured for 24/48 h in DMEM supplemented with taurine at the final concentrations of 1/10/20 mM respectively. (biomedcentral.com)
Furthermore, many studies indicate that the cholesterol-lowering effect of taurine is due to the increased biotransformation of cholesterol to bile acids in the liver and the subsequent excretion of bile acids in feces [ 5 - 7 ]. (biomedcentral.com)
Cholesterol conversion or bile acids biosynthesis is critically regulated in order to maintain cholesterol or bile acids homeostasis in the body. (biomedcentral.com)

Sequence alterations within CYP7B1 implicate defective cholesterol homeostasis in motor-neuron degeneration. (nih.gov)

The selected examples showed larger genetic effect sizes for lifestyle conditions associated with higher vis-à-vis lower average HDL-cholesterol concentrations. (nih.gov)

These results strongly suggest that polycyclic aromatic hydrocarbons perturb the metabolism of sterol in the skin of mice while keeping the total amount of cholesterol unchanged. (lookformedical.com)

Interindividual differences in plasma low-density lipoprotein cholesterol (LDL-C) levels reflect both environmental variation and genetic polymorphism, but the specific genes involved and their relative contributions to the variance in LDL-C are not known. (elsevierpure.com)

LDL + VLDL and HDL cholesterol were reduced by 56-75% and 25-41%, respectively. (nih.gov)

These results reveal an elaborate autoregulatory cascade mediated by nuclear receptors for the maintenance of hepatic cholesterol catabolism. (nih.gov)

Enzima del citocromo P450 unida a la membrana que cataliza la 7-alfa-hidroxilación del COLESTEROL en presencia de oxígeno molecular y NADPH-FERRIHEMOPROTEÍNA REDUCTASA. (bvsalud.org)

Alteration of cholesterol biosynthetic pathways in the skin of mice administered polycyclic aromatic hydrocarbons. (lookformedical.com)
Using a metabolic inhibitor, diazacholesterol, it was shown that sterols which reduce in mouse skin by administration of carcinogen and promoters were similar to those which reduce by administration of carcinogen only and are the members of one of the two cholesterol-biosynthetic pathways, i.e., a pathway which proceeds through intermediates with a saturated side chain. (lookformedical.com)

The low cholesteryl esterase activity does not result in reduced LDL-cholesterol ester degradation in mouse fibroblasts in situ. (zhangqiaokeyan.com)

BACKGROUND: The phenotypic expression of a high-density lipoprotein (HDL) genetic risk score has been shown to depend upon whether the phenotype (HDL-cholesterol) is high or low relative to its distribution in the population (quantile-dependent expressivity). (nih.gov)

Cholecalciferol is formed in the human skin from 7-dehydrocholesterol (7-DHC), a cholesterol precursor, in the presence of ultraviolet B radiation (UVB). (vitamindwiki.com)

The results (e.g., elevated acylcarnitine levels) were in agreement with previous population-based findings (6) and recovery of euthyroidism among women with Graves disease (7). (deepdyve.com)
It acts by reducing levels of cholesterol in the bile, helping gallstones that are made predominantly of cholesterol to dissolve. (illumina.com)

This suggests these reported interactions could be the result of selecting subjects for conditions that differentiate high from low HDL-cholesterol (e.g., lean vs. overweight, active vs. sedentary, high-fat vs. high-carbohydrate diets, alcohol drinkers vs. abstainers, nonsmokers vs. smokers) producing larger versus smaller genetic effect sizes. (nih.gov)

Diaza derivative of cholesterol which acts as a hypocholesteremic agent by blocking delta-24-reductase, which causes the accumulation of desmosterol. (lookformedical.com)

The abnormal buildup of cholesterol in the brain probably also contributes to the death of nerve cells. (medlineplus.gov)

LDL and total cholesterol in the coffee group at the end of the study were significantly reduced compared with the placebo group (P-values=0.003). (longdom.org)
Yet the total amount of cholesterol was not changed. (lookformedical.com)

A dose of 300 mg aminoglutethimide phosphate, which inhibits the conversion of cholesterol to 20 alpha-hydroxycholesterol, blocked the LH-induced ovulation and prevented the normal rise in plasma progesterone. (lookformedical.com)

These actions contribute to biliary cholesterol desaturation and gradual dissolution of radiolucent cholesterol gallstones in the presence of a gall-bladder visualized by oral. (illumina.com)

A great number of studies have revealed that taurine has cholesterol-lowering effect since Tsuji et al. (biomedcentral.com)

Anatomy14

Organisms7

Diseases13

Chemicals and Drugs114

Analytical, Diagnostic and Therapeutic Techniques and Equipment10

Phenomena and Processes29

Disciplines and Occupations1

Technology, Industry, Agriculture5

Information Science3

Health Care1

Chinese hamster ovary cells require the coexpression of microsomal triglyceride transfer protein and cholesterol 7alpha-hydroxylase for the assembly and secretion of apolipoprotein B-containing lipoproteins. (1/481)

The influence of estrogen on hepatic cholesterol metabolism and biliary lipid secretion in rats fed fish oil. (2/481)

High plasma cholesterol in drug-induced cholestasis is associated with enhanced hepatic cholesterol synthesis. (3/481)

Identification of a nuclear receptor for bile acids. (4/481)

CPF: an orphan nuclear receptor that regulates liver-specific expression of the human cholesterol 7alpha-hydroxylase gene. (5/481)

Lipoprotein cholesterol uptake mediates up-regulation of bile-acid synthesis by increasing cholesterol 7alpha-hydroxylase but not sterol 27-hydroxylase gene expression in cultured rat hepatocytes. (6/481)

Selective uptake of cholesteryl ester from low density lipoprotein is involved in HepG2 cell cholesterol homeostasis. (7/481)

Bile acid synthesis in the Smith-Lemli-Opitz syndrome: effects of dehydrocholesterols on cholesterol 7alpha-hydroxylase and 27-hydroxylase activities in rat liver. (8/481)

25-Hydroxyvitamin D3 1-alpha-Hydroxylase

Milk Substitutes

Cholesterol 7-alpha-Hydroxylase

Cholesterol

Cholesterol, Dietary

Cholesterol, HDL

Phenylalanine Hydroxylase

Cholesterol, LDL

Steroid 21-Hydroxylase

Cholesterol Esters

Tryptophan Hydroxylase

Cholesterol Oxidase

Tyrosine 3-Monooxygenase

Mixed Function Oxygenases

Procollagen-Proline Dioxygenase

Steroid Hydroxylases

Cholestanetriol 26-Monooxygenase

Lipids

Cholesterol, VLDL

Lipoproteins

Triglycerides

Liver

Hypercholesterolemia

Anticholesteremic Agents

Sterol O-Acyltransferase

Bile Acids and Salts

Sterols

alpha 1-Antitrypsin

Benzopyrene Hydroxylase

Lipoproteins, HDL

Adrenal Hyperplasia, Congenital

Hydroxymethylglutaryl CoA Reductases

Hydroxylation

Kinetics

4-Hydroxybenzoate-3-Monooxygenase

Hypoxia-Inducible Factor 1, alpha Subunit

Apolipoprotein A-I

Bile

Hydroxycholesterols

Cytochrome P-450 Enzyme System

Sitosterols

beta-Cyclodextrins

ATP Binding Cassette Transporter 1

Lipid Metabolism

Receptors, Adrenergic, alpha

Molecular Sequence Data

Lipoproteins, LDL

Phospholipids

Phytosterols

Base Sequence

Cyclodextrins

Esterification

Dietary Fats

ATP-Binding Cassette Transporters

Hyperlipidemias

Phosphatidylcholine-Sterol O-Acyltransferase

Hypoxia-Inducible Factor-Proline Dioxygenases

Phenylketonurias

Cholestanol

Biological Transport

Phosphatidylcholines

RNA, Messenger

Apolipoproteins

Time Factors

Lovastatin

Cholestyramine Resin

Desmosterol

Cholesterol Ester Transfer Proteins

Receptors, LDL

Mevalonic Acid

Mice, Inbred C57BL

Cells, Cultured

Filipin

Arteriosclerosis

Aniline Hydroxylase

Intestinal Absorption

Apolipoproteins B

Amino Acid Sequence

Recombinant Proteins

Hydroxymethylglutaryl-CoA Reductase Inhibitors