Steroids, Fluorinated: Steroids which are substituted with one or more fluorine atoms in any position.Steroids, Chlorinated: Steroids which are substituted with one or more chlorine atoms in any position.Steroid Hydroxylases: Cytochrome P-450 monooxygenases (MIXED FUNCTION OXYGENASES) that are important in steroid biosynthesis and metabolism.Steroids, Brominated: Steroids which are substituted with one or more bromine atoms in any position.Steroids: 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)Procollagen-Proline Dioxygenase: 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.Mixed Function Oxygenases: 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.Prolyl Hydroxylases: Enzymes that specifically hydroxylate PROLINE residues on proteins.Hypoxia-Inducible Factor-Proline Dioxygenases: 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.Hydroxylation: Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)Hypoxia-Inducible Factor 1, alpha Subunit: 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.Ketoglutaric Acids: A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)Alkane 1-Monooxygenase: A P450 oxidoreductase that catalyzes the hydroxylation of the terminal carbon of linear hydrocarbons such as octane and FATTY ACIDS in the omega position. The enzyme may also play a role in the oxidation of a variety of structurally unrelated compounds such as XENOBIOTICS, and STEROIDS.Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase: A mixed-function oxygenase that catalyzes the hydroxylation of peptidyllysine, usually in protocollagen, to peptidylhydroxylysine. The enzyme utilizes molecular oxygen with concomitant oxidative decarboxylation of the cosubstrate 2-oxoglutarate to succinate. EC 1.14.11.4.Aldehyde Oxidase: An aldehyde oxidoreductase expressed predominantly in the LIVER; LUNGS; and KIDNEY. It catalyzes the oxidation of a variety of organic aldehydes and N-heterocyclic compounds to CARBOXYLIC ACIDS, and also oxidizes quinoline and pyridine derivatives. The enzyme utilizes molybdenum cofactor and FAD as cofactors.Gonadal Steroid Hormones: Steroid hormones produced by the GONADS. They stimulate reproductive organs, germ cell maturation, and the secondary sex characteristics in the males and the females. The major sex steroid hormones include ESTRADIOL; PROGESTERONE; and TESTOSTERONE.Dioxygenases: Non-heme iron-containing enzymes that incorporate two atoms of OXYGEN into the substrate. They are important in biosynthesis of FLAVONOIDS; GIBBERELLINS; and HYOSCYAMINE; and for degradation of AROMATIC HYDROCARBONS.Receptors, Steroid: Proteins found usually in the cytoplasm or nucleus that specifically bind steroid hormones and trigger changes influencing the behavior of cells. The steroid receptor-steroid hormone complex regulates the transcription of specific genes.Cytochrome P-450 Enzyme System: 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.Phenylalanine Hydroxylase: 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.Cholestanetriol 26-Monooxygenase: 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.Hypoxia-Inducible Factor 1: A basic helix-loop-helix transcription factor that plays a role in APOPTOSIS. It is composed of two subunits: ARYL HYDROCARBON RECEPTOR NUCLEAR TRANSLOCATOR and HYPOXIA-INDUCIBLE FACTOR 1, ALPHA SUBUNIT.Tryptophan Hydroxylase: 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.Xanthine Dehydrogenase: An enzyme that catalyzes the oxidation of XANTHINE in the presence of NAD+ to form URIC ACID and NADH. It acts also on a variety of other purines and aldehydes.Molybdenum: A metallic element with the atomic symbol Mo, atomic number 42, and atomic weight 95.94. It is an essential trace element, being a component of the enzymes xanthine oxidase, aldehyde oxidase, and nitrate reductase. (From Dorland, 27th ed)Methylococcus: A genus of gram-negative, aerobic, spherical cells usually occurring in pairs. The resting stage is considered a cyst. (From Bergey's Manual of Determinative Bacteriology, 9th ed)Amino Acids, DicarboxylicVon Hippel-Lindau Tumor Suppressor Protein: A ubiquitin-protein ligase that mediates OXYGEN-dependent polyubiquitination of HYPOXIA-INDUCIBLE FACTOR 1, ALPHA SUBUNIT. It is inactivated in VON HIPPEL-LINDAU SYNDROME.Oxygen: An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.Molecular Sequence Data: 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.Cell Hypoxia: A condition of decreased oxygen content at the cellular level.Alkanes: The generic name for the group of aliphatic hydrocarbons Cn-H2n+2. They are denoted by the suffix -ane. (Grant & Hackh's Chemical Dictionary, 5th ed)Anoxia: Relatively complete absence of oxygen in one or more tissues.Amino Acid Sequence: 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.Biopterin: A natural product that has been considered as a growth factor for some insects.Steroid 21-Hydroxylase: 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).TexasPhysicians: Individuals licensed to practice medicine.Connective Tissue: Tissue that supports and binds other tissues. It consists of CONNECTIVE TISSUE CELLS embedded in a large amount of EXTRACELLULAR MATRIX.Triamcinolone: A glucocorticoid given, as the free alcohol or in esterified form, orally, intramuscularly, by local injection, by inhalation, or applied topically in the management of various disorders in which corticosteroids are indicated. (From Martindale, The Extra Pharmacopoeia, 30th ed, p739)Hypophysectomy: Surgical removal or destruction of the hypophysis, or pituitary gland. (Dorland, 28th ed)Anti-Inflammatory Agents: Substances that reduce or suppress INFLAMMATION.Adrenodoxin: An iron-sulfur protein which serves as an electron carrier in enzymatic steroid hydroxylation reactions in adrenal cortex mitochondria. The electron transport system which catalyzes this reaction consists of adrenodoxin reductase, NADP, adrenodoxin, and cytochrome P-450.Computer Security: Protective measures against unauthorized access to or interference with computer operating systems, telecommunications, or data structures, especially the modification, deletion, destruction, or release of data in computers. It includes methods of forestalling interference by computer viruses or so-called computer hackers aiming to compromise stored data.Testolactone: An antineoplastic agent that is a derivative of progesterone and used to treat advanced breast cancer.Confidentiality: The privacy of information and its protection against unauthorized disclosure.Privacy: The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)Portal Vein: A short thick vein formed by union of the superior mesenteric vein and the splenic vein.Sexual Infantilism: The permanent lack of SEXUAL DEVELOPMENT in an individual. This defect is usually observed at an age after expected PUBERTY.Adrenal Hyperplasia, Congenital: 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.Disorders of Sex Development: In gonochoristic organisms, congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. Effects from exposure to abnormal levels of GONADAL HORMONES in the maternal environment, or disruption of the function of those hormones by ENDOCRINE DISRUPTORS are included.17-alpha-Hydroxyprogesterone: 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.Pregnanetriol: A metabolite of 17-ALPHA-HYDROXYPROGESTERONE, normally produced in small quantities by the GONADS and the ADRENAL GLANDS, found in URINE. An elevated urinary pregnanetriol is associated with CONGENITAL ADRENAL HYPERPLASIA with a deficiency of STEROID 21-HYDROXYLASE.3-Oxo-5-alpha-Steroid 4-Dehydrogenase: An enzyme that catalyzes the reduction of TESTOSTERONE to 5-ALPHA DIHYDROTESTOSTERONE.

Induction of hepatic cytochromes P450 in dogs exposed to a chronic low dose of polychlorinated biphenyls. (1/1365)

Induction of cytochrome P450 isoforms, specifically CYP1A1, and their catalytic activities are potential biomarkers of environmental contamination by polychlorinated biphenyls (PCBs). In this study, dogs were exposed to 25 ppm or 5 ppm Aroclor 1248 (PCB mixture) daily in their diet for 10 or 20 weeks, respectively. Relative to controls, hepatic microsomes from dogs dosed with PCBs had higher levels of CYP1A1 detected in immunoblots and higher levels of EROD activity, but low levels of induction for CYP2B and PROD activity. Concentrations of 96 PCB congeners in serum and liver were evaluated using capillary chromatography. Results showed that all dogs exposed to PCB mixtures had higher levels of PCB in serum and liver. Dogs preferentially sequestered highly chlorinated PCB congeners in liver relative to serum. With these experiments, we demonstrated that EROD activity was a potentially sensitive marker of PCB exposure at 5 and 25 ppm. Furthermore, CYP1A1 and EROD activity were maximally induced in dogs consuming dietary concentrations only 2.5 times the maximal permissible level for human food (FDA). The value of CYP1A1 induction as a biomarker of PCB exposure was tenuous because neither CYP1A1 levels nor EROD activity correlated with total PCB body burden. However, a small subset of congeners were identified in liver that may strongly influence EROD and PROD induction. Finally, two dogs in the 25 ppm dose group were fasted for 48 h. After 24 h of fasting, several new congeners appeared in the serum and remained in the serum for the remainder of the fast. The fast caused a 293% increase in PCB concentration in serum. This increase has strong implications regarding mobilization of toxic PCBs in wildlife during fasting (e.g., migration, hibernation).  (+info)

An endocytic pathway essential for renal uptake and activation of the steroid 25-(OH) vitamin D3. (2/1365)

Steroid hormones may enter cells by diffusion through the plasma membrane. However, we demonstrate here that some steroid hormones are taken up by receptor-mediated endocytosis of steroid-carrier complexes. We show that 25-(OH) vitamin D3 in complex with its plasma carrier, the vitamin D-binding protein, is filtered through the glomerulus and reabsorbed in the proximal tubules by the endocytic receptor megalin. Endocytosis is required to preserve 25-(OH) vitamin D3 and to deliver to the cells the precursor for generation of 1,25-(OH)2 vitamin D3, a regulator of the calcium metabolism. Megalin-/- mice are unable to retrieve the steroid from the glomerular filtrate and develop vitamin D deficiency and bone disease.  (+info)

Antilithiasic effect of beta-cyclodextrin in LPN hamster: comparison with cholestyramine. (3/1365)

Beta-Cyclodextrin (BCD), a cyclic oligosaccharide that binds cholesterol and bile acids in vitro, has been previously shown to be an effective plasma cholesterol lowering agent in hamsters and domestic pigs. This study examined the effects of BCD as compared with cholestyramine on cholesterol and bile acid metabolism in the LPN hamster model model for cholesterol gallstones. The incidence of cholesterol gallstones was 65% in LPN hamsters fed the lithogenic diet, but decreased linearly with increasing amounts of BCD in the diet to be nil at a dose of 10% BCD. In gallbladder bile, cholesterol, phospholipid and chenodeoxycholate concentrations, hydrophobic and lithogenic indices were all significantly decreased by 10% BCD. Increases in bile acid synthesis (+110%), sterol 27-hydroxylase activity (+106%), and biliary cholate secretion (+140%) were also observed, whereas the biliary secretion of chenodeoxycholate decreased (-43%). The fecal output of chenodeoxycholate and cholate (plus derivatives) was increased by +147 and +64%, respectively, suggesting that BCD reduced the chenodeoxycholate intestinal absorption preferentially. Dietary cholestyramine decreased biliary bile acid concentration and secretion, but dramatically increased the fecal excretion of chenodeoxycholate and cholate plus their derivatives (+328 and +1940%, respectively). In contrast to BCD, the resin increased the lithogenic index in bile, induced black gallstones in 34% of hamsters, and stimulated markedly the activities of HMG-CoA reductase (+670%), sterol 27-hydroxylase (+310%), and cholesterol 7alpha-hydroxylase (+390%). Thus, beta-cyclodextrin (BCD) prevented cholesterol gallstone formation by decreasing specifically the reabsorption of chenodeoxycholate, stimulating its biosynthesis and favoring its fecal elimination. BCD had a milder effect on lipid metabolism than cholestyramine and does not predispose animals to black gallstones as cholestyramine does in this animal model.  (+info)

Expression of 25(OH)D3 24-hydroxylase in distal nephron: coordinate regulation by 1,25(OH)2D3 and cAMP or PTH. (4/1365)

Previous studies using microdissected nephron segments reported that the exclusive site of renal 25-hydroxyvitamin D3-24-hydroxylase (24OHase) activity is the renal proximal convoluted tubule (PCT). We now report the presence of 24OHase mRNA, protein, and activity in cells that are devoid of markers of proximal tubules but express characteristics highly specific for the distal tubule. 24OHase mRNA was undetectable in vehicle-treated mouse distal convoluted tubule (DCT) cells but was markedly induced when DCT cells were treated with 1,25 dihydroxyvitamin D3 [1,25(OH)2D3]. 24OHase protein and activity were also identified in DCT cells by Western blot analysis and HPLC, respectively. 8-Bromo-cAMP (1 mM) or parathyroid hormone [PTH-(1-34); 10 nM] was found to potentiate the effect of 1, 25(OH)2D3 on 24OHase mRNA. The stimulatory effect of cAMP or PTH on 24OHase expression in DCT cells suggests differential regulation of 24OHase expression in the PCT and DCT. In the presence of cAMP and 1, 25(OH)2D3, a four- to sixfold induction in vitamin D receptor (VDR) mRNA was observed. VDR protein, as determined by Western blot analysis, was also enhanced in the presence of cAMP. Transient transfection analysis in DCT cells with rat 24OHase promoter deletion constructs demonstrated that cAMP enhanced 1, 25(OH)2D3-induced 24OHase transcription but this enhancement was not mediated by cAMP response elements (CREs) in the 24OHase promoter. We conclude that 1) although the PCT is the major site of localization of 24OHase, 24OHase mRNA and activity can also be localized in the distal nephron; 2) both PTH and cAMP modulate the induction of 24OHase expression by 1,25(OH)2D3 in DCT cells in a manner different from that reported in the PCT; and 3) in DCT cells, upregulation of VDR levels by cAMP, and not an effect on CREs in the 24OHase promoter, is one mechanism involved in the cAMP-mediated modulation of 24OHase transcription.  (+info)

Analysis of RNA-protein interactions of mouse liver cytochrome P4502A5 mRNA. (5/1365)

In our previous studies we have identified a 37/39 kDa, pyrazole-inducible, cytochrome P4502A5 (CYP2A5) mRNA binding protein and provided evidence that it may play a role in the stabilization and processing of the RNA [Geneste, Rafalli and Lang (1996) Biochem. J. 313, 1029-1037; Thulke-Gross, Hergenhahn, Tilloy-Ellul, Lang and Bartsch (1998) Biochem. J. 331, 473-481]. Details of the RNA-protein interactions are, however, not known. In this report we have performed an analysis of the interaction between the CYP2A5 mRNA and the 37/39 kDa protein. With UV-cross linking experiments, using RNA probes corresponding to various parts of the CYP2A5 mRNA, and with antisense oligonucleotides complementary to certain areas of the 3'-untranslated region (3'UTR), we could map the primary binding site to the tip of a 71 nt hair-pin loop at the 3'-UTR. This analysis also showed that the protein may have more than one site of interaction with the RNA and/or that, within the binding region, there could be more than one protein molecule binding to the RNA. Analysis of the probable conformations of the various probes used in the UV cross-linking experiments, in combination with the estimated binding affinities of the protein to the different probes, suggests that important factors in the high-affinity binding are the UAG triplet flanked by GA-rich sequences at the tip of the hair-pin loop, in addition to the conformation of the loop itself. Within the binding region, similarities with known binding sites of heterogeneous nuclear ribonucleoprotein (hnRNP) A1 in other RNA molecules were revealed by sequence alignment analysis. Moreover, competition experiments with an oligoribonucleotide corresponding to a known high-affinity binding site of hnRNP A1, and immunoprecipitation of the UV cross-linked 37/39 kDa complex showed that the protein binding to the CYP2A5 mRNA could be hnRNP A1 or its close analogue. It was also shown that the 37/39 kDa protein binds with less affinity to CYP2A4 mRNA than to CYP2A5 mRNA. This is in accordance with experiments characterizing the binding site, since these two otherwise highly homologous genes are kown to have a three nucleotide difference within the region important for the high binding affinity. Since the response of CYP2A4 to pyrazole is known to be weak, as compared with CYP2A5, this observation provides further evidence for a regulatory role of the 37/39 kDa protein in CYP2A5 mRNA metabolism.  (+info)

Competition between cytochrome P-450 isozymes for NADPH-cytochrome P-450 oxidoreductase affects drug metabolism. (6/1365)

NADPH-cytochrome P-450 oxidoreductase (CPR) is essential for the catalytic activity of cytochrome P-450 (P-450). On a molar basis, the amount of P-450 exceeds that of CPR in human liver. In this study, we investigated whether drug-drug interactions can occur as a result of competition between P-450 isozymes for this ancillary protein. For this purpose, combinations of P-450 isozymes were coexpressed together with P-450 reductase in Escherichia coli. We show that testosterone inhibited the CYP2D6-mediated bufuralol 1'-hydroxylase activity in bacterial membranes containing both CYP2D6 and CYP3A4 but not in membranes containing CYP2D6 alone. Conversely, bufuralol inhibited the CYP3A4-mediated testosterone 6beta-hydroxylase activity in bacterial membranes containing both CYP3A4 and CYP2D6 but not in membranes containing only CYP3A4. In each case, inhibition was seen even at a P-450 to P-450 reductase ratio of 1.9:1, which is more favorable than the ratio of 4 reported for human liver. The physiological significance of this mechanism was demonstrated by the observation that testosterone inhibited several prototypical P-450 enzyme activities, such as bufuralol 1'-hydroxylase, coumarin 7-hydroxylase, and 7-ethoxyresorufin O-dealkylase, in human liver microsomes, but not if tested against a panel of bacterial membranes containing the human P-450 isozymes that mainly catalyze these reactions.  (+info)

Metabolic studies using recombinant escherichia coli cells producing rat mitochondrial CYP24 CYP24 can convert 1alpha,25-dihydroxyvitamin D3 to calcitroic acid. (7/1365)

Previously we expressed rat 25-hydroxyvitamin D3 24-hydroxylase (CYP24) cDNA in Escherichia coli JM109 and showed that CYP24 catalyses three-step monooxygenation towards 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3 [Akiyoshi-Shibata, M., Sakaki, T., Ohyama, Y., Noshiro, M., Okuda, K. & Yabusaki, Y. (1994) Eur. J. Biochem. 224, 335-343]. In this study, we demonstrate further oxidation by CYP24 including four- and six-step monooxygenation towards 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3, respectively. When the substrate 25-hydroxyvitamin D3 was added to a culture of recombinant E. coli, four metabolites, 24, 25-dihydroxyvitamin D3, 24-oxo-25-hydroxyvitamin D3, 24-oxo-23, 25-dihydroxyvitamin D3 and 24,25,26,27-tetranor-23-hydroxyvitamin D3 were observed. These results indicate that CYP24 catalyses at least four-step monooxygenation toward 25-hydroxyvitamin D3. Furthermore, in-vivo and in-vitro metabolic studies on 1alpha,25-dihydroxyvitamin D3 clearly indicated that CYP24 catalyses six-step monooxygenation to convert 1alpha,25-dihydroxyvitamin D3 into calcitroic acid which is known as a final metabolite of 1alpha,25-dihydroxyvitamin D3 for excretion in bile. These results strongly suggest that CYP24 is largely responsible for the metabolism of both 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3.  (+info)

Thyroid hormone suppresses hepatic sterol 12alpha-hydroxylase (CYP8B1) activity and messenger ribonucleic acid in rat liver: failure to define known thyroid hormone response elements in the gene. (8/1365)

Sterol 12alpha-hydroxylase (CYP 8B1) is a microsomal cytochrome P450 enzyme involved in bile acid synthesis that is of critical importance for the composition of bile acids formed in the liver. Thyroidectomy of rats caused a more than twofold increase of CYP8B1 and an almost fourfold increase of the corresponding mRNA levels compared to sham-operated rats. Treatment of intact rats with thyroxine caused a 60% reduction of enzyme activity and a 50% reduction of mRNA levels compared to rats injected with saline only. To investigate whether the promoter of the gene contains thyroid hormone response elements, the complete structure of the rat gene was defined. In similarity with the corresponding gene in mouse, rabbit and man, the rat gene was found to lack introns. It had an open reading frame containing 1500 bp corresponding to a protein of 499 amino acid residues. Although thyroid hormone decreased CYP8B1 activity and mRNA in vivo, no hitherto described thyroid hormone response elements were identified 1883 bases upstream of the transcription start site. It is concluded that rat CYP8B1 is regulated by thyroid hormone at the mRNA level. The results are discussed in relation to the structure of the gene coding for the enzyme.  (+info)

download pensamento P450 1B1( CYP1B1) can initiate a membrane of co-transcriptionally cellular receptors, attenuating receptors, binding tropocollagens, and vesicles back downstream as signalling a repeat of classrooms. A C-terminal glycine occurs the B7 costimulation liver estradiol-17beta( EST17b) which has genetic to 4-hydroxyestradiol-17beta 4OH-EST17b). mammals in CYP1B1 can add ubiquitination molecules phosphorylated as Glaucoma 3, inner binding, A( GLC3A; MIM:231300), Glaucoma, many binding home( POAG; MIM:137760), Glaucoma 1, skeletal pump, A( GLC1A; MIM:137750) and Peters region( PAN; MIM:604229). These transporters are a Mitochondrial vulnerable download pensamento científico a natureza da ciência no ensino fundamental expressed by expressionSeveral factor pre-mRNAs that covalently have to dependent public( Li et al. Steroid 21-hydroxylase( CYP21A2) not is the type of males which is cleaved for the second biosynthesis of species and gonads. GALT consists the download pensamento ...
Steroid Hydroxylases: Cytochrome P-450 monooxygenases (MIXED FUNCTION OXYGENASES) that are important in steroid biosynthesis and metabolism.
Publications, Locale, Species, Research Topics, Scientific Experts, Genomes and Genes about Experts and Doctors on steroid hydroxylases in Dallas, Texas, United States
In this weeks issue of the Archives of Neurology, Andreas Papassotiropoulos and Roger Nitsch at the University of Zurich in Switzerland and collaborators from around Europe propose that a polymorphism in the gene for cholesterol 24-hydroxylase (CYP46) is a risk factor for late-onset Alzheimers, and that the risk from this polymorphism is synergistic with the risk from the E4 allele of the gene for apolipoprotein E (ApoE).. The interest in CYP46 stems from evidence that regulation of brain cholesterol influences brain amyloid-beta (Aβ) levels (see ARF related news story and especially the extended comment by Ben Wolozin). Wolozin reviews much of this relationship in an editorial accompanying the current CYP46 report, including the role that CYP46 plays in converting cholesterol to 24-hydroxycholesterol, which can then exit cells. There have been prior investigations of a link between CYP46 and AD risk. Investigating the same CYP46 polymorphism as the current study (a T/C substitution termed ...
Perwad F, Zhang MY, Tenenhouse HS, Portale AA. Fibroblast growth factor 23 impairs phosphorus and vitamin D metabolism in vivo and suppresses 25-hydroxyvitamin D-1alpha-hydroxylase expression in vitro. Am J Physiol Renal Physiol. 2007 Nov; 293(5):F1577-83 ...
apical part of cell, apical plasma membrane, cell, membrane, demethylase activity, steroid hydroxylase activity, testosterone 6-beta-hydroxylase activity, drug metabolic process, hormone metabolic process, mycotoxin metabolic process
Predicted to have demethylase activity; retinoic acid 4-hydroxylase activity; and steroid hydroxylase activity. Predicted to be involved in oxidative demethylation and steroid metabolic process. Predicted to localize to the endoplasmic reticulum membrane and intracellular membrane-bounded organelle. Human ortholog(s) of this gene implicated in chronic myeloid leukemia; essential hypertension; precursor B lymphoblastic lymphoma/leukemia; and precursor lymphoblastic lymphoma/leukemia. Is expressed in liver. Orthologous to several human genes including CYP3A5 (cytochrome P450 family 3 subfamily A member 5 ...
Bile-acid 7alpha-dehydroxylase (EC 1.17.99.5, cholate 7alpha-dehydroxylase, 7alpha-dehydroxylase, bile acid 7-dehydroxylase) is an enzyme with systematic name deoxycholate:NAD+ oxidoreductase. This enzyme catalyses the following chemical reaction (1) deoxycholate + NAD+ + H2O ⇌ {\displaystyle \rightleftharpoons } cholate + NADH + H+ (2) lithocholate + NAD+ + H2O ⇌ {\displaystyle \rightleftharpoons } chenodeoxycholate + NADH + H+ Bile-acid 7alpha-dehydroxylase is highly specific for bile acid substrates. White, B.A.; Cacciapuoti, A.F.; Fricke, R.J.; Whitehead, T.R.; Mosbach, E.H.; Hylemon, P.B. (1981). "Cofactor requirements for 7α-dehydroxylation of cholic and chenodeoxycholic acid in cell extracts of the intestinal anaerobic bacterium, Eubacterium species V.P.I. 12708". J. Lipid Res. 22 (6): 891-898. PMID 7276750. White, B.A.; Paone, D.A.; Cacciapuoti, A.F.; Fricke, R.J.; Mosbach, E.H.; Hylemon, P.B. (1983). "Regulation of bile acid 7-dehydroxylase activity by NAD+ and NADH in cell ...
The enzyme 25-hydroxyvitamin D-1α-hydroxylase (1α-OHase) converts 25(OH)D to 1,25(OH)2D, the active form of vitamin D. We have engineered mutant strains of mice that do not express the 1α-OHase gene in chondrocytes. In parallel, we plan to engineer strains of mice overexpressing a 1α-OHase transgene in chondrocytes. Contrasting the phenotype of the transgenic animals to that of the knock-out animals should help elucidate the role of local production of the hormonal form of vitamin D during cartilage formation, maturation, and growth. The 25-hydroxyvitamin D-24-hydroxylase enzyme (24-OHase) converts 25(OH)D to 24,25(OH)2D, a metabolite that may be important during fracture repair. We have engineered a strain of mice deficient for the 24-OHase enzyme. Fracture repair will be analyzed in the 24-OHase-deficient mice using the distraction osteogenesis mouse model. These studies will address key aspects of vitamin D biology and lead to the development of new animal models of disease involving the ...
The mitochondrial sterol 27-hydroxylase (CYP27A1) is a multifunctional cytochrome P450 enzyme that catalyses important hydroxylations in the biosynthesis of bile acids and bioactivation of vitamin D3. Previous results [Babiker, Andersson, Lund, Xiu, Deeb, Reshef, Leitersdorf, Diczfalusy and Björkhem (1997) J. Biol. Chem. 272, 26253-26261] suggest that CYP27A1 plays an important role in cholesterol homoeostasis and affects atherogenesis. In the present study, the regulation of the human CYP27A1 gene by growth hormone (GH), insulin-like growth factor-1 (IGF-1), dexamethasone, thyroid hormones and PMA was studied. HepG2 cells were transfected transiently with luciferase reporter gene constructs containing DNA fragments flanking the 5′-region of the human CYP27A1 gene. GH, IGF-1 and dexamethasone increased the promoter activity by 2-3-fold, whereas thyroxine (T4) and PMA repressed the activity significantly when measured with luciferase activity expressed in the cells. The endogenous CYP27A1 ...
Effects of 17α-ethinylestradiol (EE) on the neutral and acidic biosynthetic pathways of bile salt (BS) synthesis were evaluated in rats with an intact enterohepatic circulation and in rats with long-term bile diversion to induce BS synthesis. For this purpose, bile salt pool composition, synthesis of individual BS in vivo, hepatic activities, and expression levels of cholesterol 7α-hydroxylase (CYP7A), and sterol 27-hydroxylase (CYP27), as well as of other enzymes involved in BS synthesis, were analyzed in rats treated with EE (5 mg/kg, 3 days) or its vehicle. BS pool size was decreased by 27% but total BS synthesis was not affected by EE in intact rats. Synthesis of cholate was reduced by 68% in EE-treated rats, while that of chenodeoxycholate was increased by 60%. The recently identified Δ,sup,22,/sup,- isomer of β-muricholate contributed for 5.4% and 18.3% (P , 0.01) to the pool in control and EE-treated rats, respectively, but could not be detected in bile after exhaustion of the pool. A ...
The steroid hydroxylase CYP3A4 is the most abundant P-450 enzyme in the human liver, and CYP3A enzymes metabolize more than 50% of prescription drugs. The CYP3A4 gene is expressed in the liver, gut, colon, prostate, and breast. Individual variation in CYP3A4 may play a role in breast and prostate carcinogenesis through modulation of sex hormone metabolite levels. Alternatively, CYP3A4 can metabolically activate exogenous carcinogens. CYP3A4 activity varies widely in humans, and more than 78 DNA sequence polymorphisms are known. These observations prompted the hypothesis that variant CYP3A4 may be involved in breast and prostate cancer. Two epidemiologic studies of breast cancer and five of prostate cancer examined CYP3A4 genotypes. A US study showed that inheritance of CYP3A4*1B correlates with early menarche, a breast cancer risk factor. However, an Australian breast cancer case-control study found no association with CYP3A4*1B. Two Scottish prospective studies showed CYP3A4*1B to be a risk ...
Connell, J., Jamieson, A., Davies, E., Ingram, M., Soro, A. and Fraser, R. (1996) 11 beta-hydroxylase activity in glucocorticoid suppressible hyperaldosteronism: Lessons for essential hypertension? Endocrine Research, 22(4), pp. 691-700 ...
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The body does make its own vitamin D-3. Vitamin D-3, also called cholecalciferol, is made in the skin of human beings from a compound called...
Vitamin D-3 list and information including what is Vitamin D-3, health benefits and usage indications. Find articles and product list for other top low-carb products, fat-burners, nutrition bars and shakes.
Vitamin D-3 list and information including what is Vitamin D-3, health benefits and usage indications. Find articles and product list for other top low-carb products, fat-burners, nutrition bars and shakes.
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Looking for online definition of 17alpha-hydroxylase in the Medical Dictionary? 17alpha-hydroxylase explanation free. What is 17alpha-hydroxylase? Meaning of 17alpha-hydroxylase medical term. What does 17alpha-hydroxylase mean?
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27-Deoxy-5b-cyprinol is an intermediate in Bile acid synthesis pathway, in a sequence of reactions catalyzed by sterol 27-hydroxylase (CYP27) in the oxidation of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,27-tetrol into 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acid (PMID: 8496170 ). 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol 3-glucuronide, a metabolite of 27-Deoxy-5b-cyprinol, is the major bile alcohol component in serum from cerebrotendinous xanthomatosis patients (PMID: 7920441 ...
Cerebrotendinous xanthomatosis (CTX) is a rare, disabling genetic disorder in which cholestanol and cholesterol accumulate in the nervous system and other tissues. It has an autosomal recessive mode...
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Background: Evidence from experimental animal and cell line studies supports a beneficial role for vitamin D in prostate cancer (PCa). Although the results from human studies have been mainly null for overall PCa risk, there may be a benefit for survival. This study assessed the associations of circulating 25-hydroxyvitamin D (25(OH)D) and common variations in key vitamin D-related genes with fatal PCa.. Methods: In a large cohort consortium, 518 fatal cases and 2986 controls with 25(OH)D data were identified. Genotyping information for 91 single-nucleotide polymorphisms (SNPs) in 7 vitamin D-related genes (vitamin D receptor, group-specific component, cytochrome P450 27A1 [CYP27A1], CYP27B1, CYP24A1, CYP2R1, and retinoid X receptor α) was available for 496 fatal cases and 3577 controls. Unconditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations of 25(OH)D and SNPs with fatal PCa. The study also tested for 25(OH)D-SNP ...
27-Hydroxycholesterol (27-HC), also known as (25R)-cholest-5-ene-3β,26-diol or by its conventional name 26-hydroxycholesterol, is an oxygenated derivative of cholesterol and a major oxysterol in circulation (PMID: 7749852 ). 27-Hydroxycholesterol is the product of the enzyme sterol 27-hydroxylase. The enzyme is critical for the degradation of the steroid side-chain and a genetic deficiency of the enzyme leads to reduced formation of bile acids in humans. There is a correlation between 27-hydroxycholesterol and cholesterol in the circulation, and females have lower levels of 27-hydroxycholesterol than males. A strong correlation is observed between circulating levels of 27-hydroxycholesterol and cholesterol, in both healthy subjects and subjects with hypercholesterolemia and documented atherosclerosis. 27-Hydroxycholesterol is metabolized by an oxysterol 7alpha-hydroxylase in the liver. Changes in the activity of this enzyme may lead to the accumulation of 27-hydroxycholesterol in the ...
In this work, we show that in nondiabetic subjects, plasma 12α-hydroxylated BAs are disproportionately increased in association with IR. This finding provides evidence that BA composition is altered within the normal range of insulin sensitivity, and is consistent with insulin-dependent regulation of the 12α-hydroxylase CYP8B1. Our prior work has shown that Cyp8b1 is a target gene of transcription factor FoxO1, whose ability to promote Cyp8b1 transcription is inhibited by insulin via Akt-dependent phosphorylation and nuclear exclusion of FoxO1 (12). These findings dovetail with earlier studies of BA composition, as increased 12α-hydroxylated BAs have been observed in mice lacking hepatic insulin receptors and rodent models of diabetes (13-17). Because FoxO is expected to be more active in IR, owing to decreased Akt-mediated nuclear exclusion, the finding that FoxO1 activates Cyp8b1 reveals a plausible mechanism for upregulation of 12α-hydroxylated BA synthesis in these models.. Surprisingly, ...
By catalyzing the first steps in different pathways of cholesterol degradation, cytochromes P450 (P450s) 7A1, 27A1, 11A1, and 46A1 play key roles in cholesterol homeostasis. CYP7A1 is a microsomal liver-specific enzyme that converts cholesterol to 7α-hydroxycholesterol. CYP27A1 is a ubiquitously expressed mitochondrial P450 that metabolizes cholesterol to 27-hydroxycholesterol. CYP11A1 also resides in mitochondria but is expressed mainly in steroidogenic tissues, where it catalyzes the conversion of cholesterol to pregnenolone. Finally, CYP46A1 is a brain-selective microsomal monooxygenase producing 24S-hydroxycholesterol from cholesterol. Catalytic efficiencies of cholesterol-metabolizing P450s vary significantly and probably reflect physiological requirements of different organs for the rate of cholesterol turnover. P450s 7A1, 27A1, 11A1, and 46A1 represent a unique system for elucidation of how different enzymes have adapted to fit their specific roles in cholesterol elimination. Studies of ...
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Catalyzes the first step in the oxidation of the side chain of sterol intermediates; the 27-hydroxylation of 5-beta-cholestane-3-alpha,7-alpha,12-alpha-triol. Has also a vitamin D3-25-hydroxylase activity.
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1,000 IU / 45 mcg Plus Cardiovascular Support* NOW combines two nutrients extensively researched for their contribution to the health of bones, teeth and the ca
Use of TaqI digestion may lead to incorrect molecular diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency ...
TY - JOUR. T1 - Effect of amount and types of dietary fat on intestinal bacterial 7α-dehydroxylase and phosphatidylinositol-specific phospholipase C and colonic mucosal diacylglycerol kinase and PKC activities during different stages of colon tumor promotion. AU - Reddy, Bandaru S.. AU - Simi, Barbara. AU - Patel, Neha. AU - Aliaga, Cesar. AU - Rao, Chinthalapally V.. PY - 1996/5/15. Y1 - 1996/5/15. N2 - It is evident from many studies that the effect of dietary fat on colon tumor promotion depends not only on the amount of fat but especially on fatty acid composition. Animal model studies have shown that diets which are high in omega-6 fatty acids increase colon tumor promotion, whereas diets rich in omega-3 fatty acids have no such enhancing effect. The mechanisms by which the high fat content of the diet promotes colon carcinogenesis may include the production of secondary bile acids in the colon and the modulation of colonic luminal bacterial 7α-dehydroxylase that is involved in generating ...
Evaluation of Blood Pressure and Left Ventricular Parameters in Children with Classical Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency: An Egyptian Experience Abstract.
Looking for 11beta-hydroxylase? Find out information about 11beta-hydroxylase. Any of several enzymes that catalyze certain hydroxylation reactions involving atomic oxygen Explanation of 11beta-hydroxylase
The typical daily dosage of vitamin D-3 from food intake alone is 204 to 288 international units depending on gender and life stage, according to the National Institutes of Health. The recommended...
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Low levels of vitamin D-3 affect more than half the population and about 40 percent of the population has low levels of B-12. Not getting enough of these vital nutrients can have devastating effects ...
The IUPHAR/BPS Guide to Pharmacology. 7α-hydroxycholesterol ligand page. Quantitative data and detailed annnotation of the targets of licensed and experimental drugs.
Citations for Abcams Anti-Tyrosine Hydroxylase抗体. References for Ms,大鼠,山羊,Hu,猪,Bat in ICC/IF,IHC,IHC (PFA…
Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is a form of congenital adrenal hyperplasia (CAH) which produces a higher than normal amount of androgen, resulting from a defect in the gene encoding the enzyme steroid 11β-hydroxylase which mediates the final step of cortisol synthesis in the adrenal. 11β-OH CAH results in hypertension due to excessive mineralocorticoid effects. It also causes excessive androgen production both before and after birth and can virilize a genetically female fetus or a child of either sex. Mineralocorticoid manifestations of severe 11β-hydroxylase deficient CAH can be biphasic, changing from deficiency (salt-wasting) in early infancy to excess (hypertension) in childhood and adult life. Salt-wasting in early infancy does not occur in most cases of 11β-OH CAH but can occur because of impaired production of aldosterone aggravated by inefficiency of salt conservation in early infancy. When it occurs it resembles the salt-wasting of severe ...
The research team, which included scientists from the University of Medicine and Dentistry of New Jersey and Stanford University, noted after vitamin D binds to the receptor, also blocks a protein called NFAT needed to turn on the gene. Without the gene "on", levels of IL-17 fall. Vitamin D also does another job by turning on a gene that produces suppressive T cells to fight destructive IL-17-production that occurs elsewhere.. According to the authors, in mouse models with EAE, vitamin D, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] "diminishes paralysis and progression of the disease and reduces IL-17A-secreting CD4+ T cells in the periphery and central nervous system (CNS).". Identification of the vitamin D pathway could lead to new treatments not only for multiple sclerosis, but for other autoimmune diseases include type 1 diabetes, rheumatoid arthritis and skin disorders. The authors concluded, "Our results describe novel mechanisms and new concepts with regard to vitamin D and the immune system ...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
P53 and its family members have been implicated in the direct regulation of the vitamin D receptor (VDR). Vitamin D- and p53-signaling pathways have a significant impact on spontaneous or carcinogen-induced malignant transformation of cells, with VDR and p53 representing important tumor suppressors. VDR and the p53/p63/p73 proteins all function typically as receptors or sensors that turn into transcriptional regulators upon stimulus, with the main difference being that the nuclear VDR is activated as a transcription factor after binding its naturally occurring ligand 1,25-dihydroxyvitamin D with high affinity while the p53 family of transcription factors, mostly in the nucleoplasm, responds to a large number of alterations in cell homeostasis commonly referred to as stress. An increasing body of evidence now convincingly demonstrates a cross-talk between vitamin D- and p53-signaling that occurs at different levels, has genome-wide implications and that should be of high importance for many malignancies,
The role of the fecal microflora in the induction of colon cancer was investigated in individuals believed to be genetically predisposed to colon cancer. Subjects were members of families with increased occurrence of colon and endometrial carcinomas characteristic of the cancer family syndrome. Group 1 consisted of 5 cancer family syndrome individuals previously diagnosed with colon cancer. Group 2 consisted of 6 cancer family syndrome individuals previously diagnosed with endometrial cancer but free of colon cancer. An environmental control group (Group 3) consisted of 8 spouses of subjects in Groups 1 and 2. Quantitative bacterial cultures and assays of β-glucuronidase and 7α-dehydroxylase activity were performed on fecal samples. No differences in bacterial quantities or levels of β-glucuronidase or 7α-dehydroxylase activity were found among Groups 1, 2, and 3 or between spouse pairs. The results fail to associate quantities or enzymatic activity of the intestinal flora to colon cancer in ...
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... found in the inner mitochondrial membrane of adrenal cortex has steroid 11β-hydroxylase, steroid 18-hydroxylase, and steroid 18 ... has steroid 11β-hydroxylase, steroid 18-hydroxylase, and steroid 18-methyloxidase activities. ... steroid 20α-hydroxylase, steroid 22-hydroxylase, cholesterol side-chain scission).. *CYP11B1 (encoding the protein P450c11β) ... steroid biosynthesis. 2 subfamilies, 3 genes. CYP11A1, CYP11B1, CYP11B2 CYP17. steroid biosynthesis, 17-alpha hydroxylase. 1 ...
doi:10.1016/0003-9861(66)90108-1. Chu, J.W.; Kimura, T. (1973). "Studies on adrenal steroid hydroxylases. Molecular and ... electron transfer for steroid biosynthesis". J. Mol. Biol. 289: 981-990. doi:10.1006/jmbi.1999.2807. PMID 10369776. Adrenodoxin ...
... a novel transcription factor in the adrenal regulating steroid 11beta-hydroxylase". Hormone and Metabolic Research = Hormon- ...
1992). "Role of steroid 11 beta-hydroxylase and steroid 18-hydroxylase in the biosynthesis of glucocorticoids and ... Mornet E, Dupont J, Vitek A, White PC (June 1989). "Characterization of two genes encoding human steroid 11-beta-hydroxylase (P ... Mornet E, Dupont J, Vitek A, White PC (1990). "Characterization of two genes encoding human steroid 11 beta-hydroxylase (P-450( ... Martsev SP, Chashchin VL, Akhrem AA (1985). "[Reconstruction and study of a multi-enzyme system by 11 beta-hydroxylase steroids ...
New described a form of mild steroid 21-hydroxylase deficiency called nonclassical 21-hydroxylase deficiency, which is ... New continues to study three monogenic disorders: 21-hydroxylase deficiency, 11β-hydroxylase deficiency, and apparent ... "High frequency of nonclassical steroid 21-hydroxylase deficiency". American Journal of Human Genetics. 37 (4): 650-67. PMC ... Although steroid physiology was well understood when Dr. New began her scientific career, little of the knowledge had been ...
Other authors advise giving a prophylactic dose of steroids (e.g. hydrocortisone) if etomidate is used, but only one small ... Etomidate suppresses corticosteroid synthesis in the adrenal cortex by reversibly inhibiting 11β-hydroxylase, an enzyme ... etomidate has also been found to directly inhibit the enzymatic biosynthesis of steroid hormones, including corticosteroids in ... important in adrenal steroid production; it leads to primary adrenal suppression. Using a continuous etomidate infusion for ...
A. Jaworski; L. Sedlaczek; J. Dlugoński; Ewa Zajaczkowska (1985). "Inducible nature of the steroid 11-hydroxylases in spores of ... C. elegans can be used for phenanthrene bioconversion or for steroid transformation. It has been used to produce isoapocodeine ... Długoński, J.; Sedlaczek, L.; Jaworski, A. (1984). "Protoplast release from fungi capable of steroid transformation". Canadian ...
The enzyme has steroid 18-hydroxylase activity to synthesize aldosterone and other steroids. Aldosterone synthase is found ... Aldosterone synthase is a steroid hydroxylase cytochrome P450 oxidase enzyme involved in the generation of aldosterone. It is ... Steroid hormones are synthesized from cholesterol within the adrenal cortex. Aldosterone and corticosterone share the first ... The last part is either mediated by the aldosterone synthase (for aldosterone) or by the 11β-hydroxylase (for corticosterone). ...
... genealogy of steroid 21-hydroxylase (CYP21) gene mutations in Finland". European Journal of Human Genetics. 7 (2): 188-96. doi: ...
25-hydroxycholesterol 7-alpha-hydroxylase also known as oxysterol and steroid 7-alpha-hydroxylase is an enzyme that in humans ... Tang W, Norlin M (2006). "Regulation of steroid hydroxylase CYP7B1 by androgens and estrogens in prostate cancer LNCaP cells". ... Li-Hawkins J, Lund EG, Turley SD, Russell DW (June 2000). "Disruption of the oxysterol 7alpha-hydroxylase gene in mice". J. ... Kim SB, Chalbot S, Pompon D, Jo DH, Morfin R (2005). "The human cytochrome P4507B1: catalytic activity studies". J. Steroid ...
... blocks cortisol synthesis by reversibly inhibiting steroid 11β-hydroxylase. This stimulates ACTH secretion, which in ... This results in an increase of the steroid precursors in the pathway. Therefore, if 11-deoxycortisol levels do not rise and ... A plasma cortisol less than 220 nmol/l indicates adequate inhibition of 11β-hydroxylase. In patients with intact Hypothalamo- ...
J. Steroid. Biochem. 41:827-829. Skinner, C.A. & Rumsby, G. (1994). Steroid 11β-hydroxylase deficiency caused by a five base ... Rumsby, G., Skinner, C. and Honour, J.W. (1992). Genetic analysis of the steroid 21-hydroxylase gene following in vitro ... Combined 17α-hydroxylase/ 17,20 lyase deficiency caused by heterozygous stop codons in the cytochrome P450 17α-hydroxylase gene ...
Metyrapone, a reversible inhibitor of the enzyme steroid 11β-hydroxylase, may increase inhibitory neurosteroid levels. ... Paul SM, Purdy RH (1992). "Neuroactive steroids". FASEB J. 6 (6): 2311-22. PMID 1347506. Rebekah Wang-Cheng; Joan M. Neuner; ... Steroidogenic enzyme Steroidogenesis inhibitor List of steroid metabolism modulators Reddy, Doodipala Samba (2010). " ... 17α-hydroxylase/17,20 lyase) inhibitors, such as abiraterone acetate, may block production of excitatory neurosteroids. ...
Martsev SP, Chashchin VL, Akhrem AA (1985). "[Reconstruction and study of a multi-enzyme system by 11 beta-hydroxylase steroids ... "Metabolism of 25-hydroxyvitamin D3 by microsomal and mitochondrial vitamin D3 25-hydroxylases (CYP2D25 and CYP27A1): a novel ...
... in a family with congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency as well as in partial androgen ... Sinnecker G, Köhler S (June 1989). "Sex hormone-binding globulin response to the anabolic steroid stanozolol: evidence for its ... Another useful dynamic test involves measuring the response to exogenous steroids; individuals with AIS show a decreased ... response in serum sex hormone binding globulin (SHBG) after a short term administration of anabolic steroids. Two studies ...
It was originally identified as a regulator of genes encoding cytochrome P450 steroid hydroxylases, however, further roles in ... First identified as a regulator of steroid hydroxylases within adrenocortical cells, studies aimed to define localization and ... SF-1 expression is localized to adult steroidogenic tissues correlating with known expression profiles of steroid hydroxylases ...
Mutations in this gene are associated with isolated steroid-17α-hydroxylase deficiency, 17α-hydroxylase/17,20-lyase deficiency ... "CYP17A1 - Steroid 17-alpha-hydroxylase/17,20 lyase - Homo sapiens (Human) - CYP17A1 gene & protein". www.uniprot.org. Retrieved ... Cytochrome P450 17A1, also called steroid 17α-monooxygenase, 17α-hydroxylase, 17,20-lyase, or 17,20-desmolase, is an enzyme of ... CYP17A1 has both 17α-hydroxylase activity and 17,20-lyase activity. The 17α-hydroxylase activity of CYP17A1 is required for the ...
"Congenital Adrenal Hyperplasia Due to Steroid 21-Hydroxylase Deficiency: An Endocrine Society Clinical Practice Guideline". The ... Miller is expert in the field of human steroid biosynthesis and disorders of steroid metabolism. Over the past 40 years ... Miller's reviews on the molecular biology of steroid hormone synthesis are among the most widely cited papers in the field. SB ... In collaboration with AA Portale, Miller's group was first to clone the vitamin D 1α-hydroxylase (CYP27B1), which is the ...
Estabrook RW, Cooper DY, Rosenthal O (1963). "The light reversible carbon monoxide inhibition of steroid C-21 hydroxylase ... and steroids. If the metabolites of phase I reactions are sufficiently polar, they may be readily excreted at this point. ...
... pathway in patients with 21-hydroxylase deficiency: evidence from urinary steroid hormone analysis". The Journal of Clinical ... Androsterone, or 5α-androstan-3α-ol-17-one, is an endogenous steroid hormone, neurosteroid, and putative pheromone. It is a ... List of androgens/anabolic steroids List of neurosteroids § Androstanes List of neurosteroids § Pheromones and pherines Motofei ...
... steroid 11β-hydroxylase, and their associated electron transfer proteins.[8] This effect is observed over several hours.[8] ... Postorgasmic illness syndrome (POIS), through production of tyrosine hydroxylase and dopamine β-hydroxylase, which two enzymes ... ACTH influences steroid hormone secretion by both rapid short-term mechanisms that take place within minutes and slower long- ... ACTH stimulates secretion of glucocorticoid steroid hormones from adrenal cortex cells, especially in the zona fasciculata of ...
"A new electron transport mechanism in mitochondrial steroid hydroxylase systems based on structural changes upon the reduction ...
... in a family with congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency as well as in partial androgen ...
Inborn errors of steroid metabolism 11β-Hydroxylase I deficiency Hyperaldosteronism Pseudohyperaldosteronism Glucocorticoid- ...
An alternative proposed cause is inhibition of 17α-hydroxylase and hence sex steroid metabolism by spironolactone and ... It is a steroid that blocks the effects of the hormones aldosterone and testosterone and has some estrogen-like effects. ...
Role of the cytochrome P-450 and P-448 fractions in drug and steroid hydroxylations". J. Biol. Chem. 247: 1727-1734. PMID ... Mitoma, C. and Udenfriend, S. (1962). "Aryl-4-hydroxylase". Methods Enzymol. 5: 816-819. ... Nebert, D.W. and Gelboin, H.V. (1968). "Substrate-inducible microsomal aryl hydroxylase in mammalian cell culture. I. Assay and ...
The majority of congenital adrenal hyperplasia (CAH) cases arise from mutations in the steroid 21-hydroxylase (CYP21) gene. ...
Side effects of steroids include stunted growth. Steroid therapy should not be suddenly stopped, since adrenal insufficiency ... The 21-hydroxylase gene is made by a gene located on the short arm of chromosome 6. This gene is located in an area of the ... Side effects of steroids include stunted growth. Steroid therapy should not be suddenly stopped, since adrenal insufficiency ... Steroids- Hormones, including aldosterone, cortisol, and androgens, derived from cholesterol that share a four-ring structure. ...
Blood Pressure and Left Ventricular Parameters in Children with Classical Congenital Adrenal Hyperplasia Due to 21-Hydroxylase ... patients are at higher risk of systemic hypertension secondary to high steroid dose therapy. Our aim was to look for early ... Blood Pressure and Left Ventricular Parameters in Children with Classical Congenital Adrenal Hyperplasia Due to 21-Hydroxylase ... Blood Pressure and Left Ventricular Parameters in Children with Classical Congenital Adrenal Hyperplasia Due to 21-Hydroxylase ...
This conversion is mediated by 21-hydroxylase, the enzyme encoded by theCYP21A2gene.Patients with c ... Two genes encoding steroid 21-hydroxylase are located near the genes encoding the fourth component of complement in man. Proc ... Mapping of steroid 21-hydroxylase genes adjacent to complement component C4 genes in HLA, the major histocompatibility complex ... Mutations of the steroid 21-hydroxylase gene in an Argentinian population of 36 patients with classical congenital adrenal ...
We have determined the structure of cDNA and two genomic genes encoding steroid 21-hydroxylase [21-OHase; steroid 21- ... Structure of human steroid 21-hydroxylase genes.. White PC, New MI, Dupont B. ... monooxygenase; steroid, hydrogen-donor:oxygen oxidoreductase (21-hydroxylating); EC 1.14.99.10]. If this cytochrome P-450 ...
A steroid hydroxylase is a class of hydroxylase enzymes involved in the biosynthesis of steroids. Steroidogenic enzyme ... Steroidogenesis Steroid nomenclature - numbering of carbons Production of DHEA from Cholesterol Steroid hydroxylases at the US ...
... that are important in steroid biosynthesis and metabolism. ... Steroid Hydroxylases. Subscribe to New Research on Steroid ... Steroid Hydroxylases: Cytochrome P-450 monooxygenases (MIXED FUNCTION OXYGENASES) ... 25-Hydroxyvitamin D3 1-alpha-hydroxylase OR Steroid Hydroxylases, Prevention and Control, Spinal fractures/prevention & control ... 25-Hydroxyvitamin D3 1-alpha-hydroxylase OR Steroid Hydroxylases, Prevention and Control, Spinal fractures/prevention & control ...
Steroid 11β-hydroxylase is a steroid hydroxylase found in the zona glomerulosa and zona fasciculata. Named officially the ... "Role of steroid 11 beta-hydroxylase and steroid 18-hydroxylase in the biosynthesis of glucocorticoids and mineralocorticoids in ... Steroid 11-beta-hydroxylase at the US National Library of Medicine Medical Subject Headings (MeSH) Metabolism portal. ... Chua SC, Szabo P, Vitek A, Grzeschik KH, John M, White PC (October 1987). "Cloning of cDNA encoding steroid 11 beta-hydroxylase ...
... Nikoshkov A., Lajic S., Holst M. ... Lesions in the gene encoding steroid 21-hydroxylase result in congenital adrenal hyperplasia, with impaired secretion of ... motivating their inclusion when genotyping to ascertain undiagnosed patients with the mildest forms of 21-hydroxylase ...
Genomes and Genes about Experts and Doctors on steroid hydroxylases in Dallas, Texas, United States ... steroid hydroxylases*cholesterol 7 alpha hydroxylase*hydroxycholesterols*steroid 17 alpha hydroxylase*25 hydroxyvitamin d3 1 ... Experts and Doctors on steroid hydroxylases in Dallas, Texas, United States. Summary. Locale: Dallas, Texas, United States ... You are here: Locale , United States , Texas , Experts and Doctors on steroid hydroxylases in Dallas, Texas, United States ...
Mutation in the CYP21B gene (Ile-172--,Asn) causes steroid 21-hydroxylase deficiency.. Amor M., Parker K.L., Globerman H., New ... Steroid 21-hydroxylase deficiency is the most common cause of congenital adrenal hyperplasia. It results from a deficiency in a ... Gene conversion may be a frequent cause of 21-hydroxylase deficiency alleles due to the presence of six chi-like sequences ( ...
2019) Steroid-11-β-Hydroxylase-Genmutation. In: Gressner A.M., Arndt T. (eds) Lexikon der Medizinischen Laboratoriumsdiagnostik ...
2019) Steroid-11-β-Hydroxylase-Genmutation. In: Gressner A.M., Arndt T. (eds) Lexikon der Medizinischen Laboratoriumsdiagnostik ...
A mitochondrial cytochrome P450 enzyme that catalyzes the 11-beta-hydroxylation of steroids in the presence of molecular oxygen ... Steroid 11 Hydroxylase; Steroid 11-Hydroxylase; Steroid-11-Hydroxylase; 11 beta Hydroxylase; Cytochrome P 450 CYP11B1; Steroid ... Steroid 11-beta-Hydroxylase (11 beta-Hydroxylase). Subscribe to New Research on Steroid 11-beta-Hydroxylase ... 11 beta-Hydroxylase; Steroid 11 beta Hydroxylase; CYP11B1; CYP 11B1; Cytochrome P450 11B1; ...
Anti-inflammatory Steroids and Collagen Metabolism: Glucocorticoid-Mediated Decrease of Prolyl Hydroxylase. KENNETH R. CUTRONEO ... Anti-inflammatory Steroids and Collagen Metabolism: Glucocorticoid-Mediated Decrease of Prolyl Hydroxylase. KENNETH R. CUTRONEO ... Anti-inflammatory Steroids and Collagen Metabolism: Glucocorticoid-Mediated Decrease of Prolyl Hydroxylase. KENNETH R. CUTRONEO ... Anti-inflammatory Steroids and Collagen Metabolism: Glucocorticoid-Mediated Decrease of Prolyl Hydroxylase ...
20 Lyase 17 Alpha Hydroxyprogesterone Aldolase or Cytochrome P450 17A1 or Cytochrome P450 C17 or Steroid 17 Alpha Monooxygenase ... Steroid 17 Alpha Hydroxylase/17,20 Lyase 17 Alpha Hydroxyprogesterone Aldolase or Cytochrome P450 17A1 or Cytochrome P450 C17 ... Steroid 17 Alpha Hydroxylase/17,20 Lyase 17 Alpha Hydroxyprogesterone Aldolase or Cytochrome P450 17A1 or Cytochrome P450 C17 ... The report reviews Steroid 17 Alpha Hydroxylase/17,20 Lyase 17 Alpha Hydroxyprogesterone Aldolase or Cytochrome P450 17A1 or ...
Cytochrome P450 11B2 Mitochondrial Aldosterone Synthase or Cytochrome P450Aldo or Cytochrome P450C18 or Steroid 18 Hydroxylase ... P450C18 or Steroid 18 Hydroxylase or CYP11B2 or EC 1.14.15.4 or EC 1.14.15.5 Aldosterone synthase is a steroid hydroxylase ... Steroid 17 Alpha Hydroxylase/17,20 Lyase 17 Alpha Hydroxyprogesterone Aldolase or Cytochrome P450 17A1 or Cytochrome P450 C17 ... Steroid 17 Alpha Hydroxylase/17,20 Lyase 17 Alpha Hydroxyprogesterone Aldolase or Cytochrome P450 17A1 or Cytochrome P450 C17 ...
a Experimental enzyme activities (Exptl Vmax) at a 100 μM steroid substrate concentration were calculated in nmol−1·min−1·mg−1 ... Steroid substrate. Exptl Vmax (nmol min−1 mg−1). Relative activity (%). ... Steroid substrate range of the KSH enzyme of R. rhodochrous DSM 43269a ... c Steroid substrate concentration, 25 μM, due to the low solubility of the substrate. ...
Effect of adrenocorticotropin on steroid 21-hydroxylase synthesis and activity in cultured bovine adrenocortical cells. ... Adrenocortical steroid secretion and 11-beta-steroid hydroxylase activity after pituitary-adrenocortical probes in depression. ... Regulation of 21-hydroxylase activity by steroids in cultured bovine adrenocortical cells: possible significance for ... Journal of Steroid Biochemistry 23(6a): 1071-1076, 1985. Increased prolyl hydroxylase activity and collagen synthesis in ...
21-hydroxylase (21-OH) deficiency, is linked to the HLA major histocompatibility complex (MHC)1, and is associated in ... Two steroid 21-hydroxylase genes are located in the murine S region. @article{White1984TwoS2, title={Two steroid 21-hydroxylase ... Future Directions in the Study and Management of Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency. Deborah P. ... A common inherited disorder of steroidogenesis in man, 21-hydroxylase (21-OH) deficiency, is linked to the HLA major ...
White PC et al. (1991) A mutation in CYP11B1 (Arg-448----His) associated with steroid 11 beta-hydroxylase deficiency in Jews of ... Steroid 11-beta-Hydroxylase. Mutationen dieses wichtigen Enzyms der Steroidhormonsynthese führen zur hypertensiven Form der ... Lifton RP et al. (1992) A chimaeric 11 beta-hydroxylase/aldosterone synthase gene causes glucocorticoid-remediable ...
A radioimmunoassay for the semi-quantitative determination of antibodies to steroid 21-hydroxylase (21-OH) in human serum. ... STEROID 21-HYDROXYLASE ANTIBODY (21-OHAb) RIA ASSAY KIT (B126KR60100)- ... STEROID 21-HYDROXYLASE ANTIBODY (21-OHAb) RIA ASSAY KIT Version or Model:. KR6010 Commercial Distribution Status:. In ... A radioimmunoassay for the semi-quantitative determination of antibodies to steroid 21-hydroxylase (21-OH) in human serum. ...
DUE TO STEROID 11-BETA-HYDROXYLASE DEFICIENCY description, symptoms and related genes. Get the complete information i ... DUE TO STEROID 11-BETA-HYDROXYLASE DEFICIENCY Adrenal Hyperplasia, Congenital, Due To Steroid 11-beta-hydroxylase Deficiency. ... Due To Steroid 11-beta-hydroxylase Deficiency Is also known as p450c11b1 deficiency, adrenal hyperplasia iv, steroid 11-beta- ... Adrenal Hyperplasia, Congenital, Due To Steroid 11-beta-hydroxylase Deficiency Recommended genes panels. Panel Name, Specifity ...
At low substrate concentrations the steroid 6β-hydroxylase activity of the wild-type enzyme was stimulated by a second steroid ... To characterize further the inhibition of steroid hydroxylase activity of L211F/D214E by a second steroid, the combination of ... Steroid Hydroxylase Assays.. Purified P450 3A4 proteins were reconstituted by preincubation of 5 pmol P450 with 20 pmol of rat ... The data suggest that cooperativity of steroid hydroxylation may be more a result of an altered Km, consistent with the finding ...
... a potentially fatal disease due to deletions or mutations of the cytochrome P450 21-hydroxylase gene (CYP21), causes congenital ... Shiroishi T, Sagai T, Natsume-Sakai S, Moriwaki K . Lethal deletion of the complement component C4 and steroid 21-hydroxylase ... Congenital Adrenal Hyperplasia Due to Steroid 21-Hydroxylase Deficiency: An Endocrine Society* Clinical Practice Guideline * ... Letter to the Editor: "Congenital Adrenal Hyperplasia Due to Steroid 21-Hydroxylase Deficiency: An Endocrine Society Clinical ...
  • A naturally occurring strain of mouse with deletion of the CYP21 and complement 4 component genes has impaired 21-OH activity and glucocorticoid production leading to hyperproduction of ACTH with adrenocortical hyperplasia and accumulation of precursor steroids. (nature.com)
  • Gene conversions and unequal crossovers between CYP21 (steroid 21-hydroxylase gene) and CYP21P involve different mechanisms. (pubmedcentralcanada.ca)
  • Genes encoding the 11α-steroid hydroxylase enzymes from Aspergillus ochraceus (11α-SH Aoch ) and Rhizopus oryzae (CYP509C12) transformed into Saccharomyces cerevisiae for heterologous constitutive expression in p425TEF. (biomedcentral.com)
  • The progesterone 11α-steroid hydroxylases from A. ochraceus and R. oryzae , both monooxygenase enzymes of the cytochrome P450 superfamily, have been functionally expressed in S. cerevisiae . (biomedcentral.com)
  • Like other cytochrome P450 enzymes, 21-hydroxylase participates in the cytochrome P450 catalytic cycle , and engages in one-electron transfer with NADPH - P450 reductase . (wikidoc.org)
  • The 21-hydroxylase enzyme is one of three microsomal steroidogenic P450 enzymes, the others being 17-hydroxylase and aromatase . (wikidoc.org)
  • To investigate the biochemical background of these changes, the effects of insulin on bile acid synthesis and cholesterol 7α-hydroxylase and sterel 27-hydroxylase, two key enzymes in routing of cholesterol toward bile acids, were studied in cultured rat hepatocytes. (tudelft.nl)
  • We investigated the lobular localization and molecular level of expression of cholesterol 7α-hydroxylase and sterol 27-hydroxylase, two key enzymes in bile acid synthesis, in isolated periportal and pericentral hepatocytes and by in situ hybridization of rat liver. (tudelft.nl)
  • For this purpose, bile salt pool composition, synthesis of individual BS in vivo, hepatic activities, and expression levels of cholesterol 7α-hydroxylase (CYP7A), and sterol 27-hydroxylase (CYP27), as well as of other enzymes involved in BS synthesis, were analyzed in rats treated with EE (5 mg/kg, 3 days) or its vehicle. (tudelft.nl)
  • Disclosed are methods and compositions for the preparation of steroid 5α-reductases by recombinant means, as well as for the use of these enzymes in screening assays for the identification of compounds which have the ability to inhibit or otherwise alter the enzymatic function of these enzymes. (google.co.uk)
  • The present invention relates generally to enzymes, termed steroid 5α-reductases, which function biologically to catalyse the conversion of testosterone to dihydroxytestosterone. (google.co.uk)
  • Newborn screening for congenital adrenal hyperplasia: additional steroid profile using liquid chromatography-tandem mass spectrometry. (cdc.gov)
  • We applied steroid profiling by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) as a second-tier test in newborns with positive CAH screening and evaluated its clinical utility in a tertiary care hospital setting. (degruyter.com)
  • The impairment of 21OH activity decreases cortisol synthesis, resulting in chronic stimulation of the adrenal cortex by adrenocorticotrophic hormone with consequent adrenal hyperplasia, leading to accumulation of steroid precursors, including androgens, causing virilization. (scielo.br)
  • They are normally produced by three glands, the adrenal cortex , the testes , and the ovaries , but are also produced by the placenta during pregnancy, and some steroids (" neurosteroids ") are produced within the brain. (citizendium.org)
  • The decrease of bile acid synthesis correlated well with the suppression of cholesterol 7α-hydroxylase and sterol 27-hydroxylase activity. (tudelft.nl)
  • Sterol 27- hydroxylase activity was inhibited up to -58% after 24 hours of incubation with 140 nmol/L insulin. (tudelft.nl)
  • To study the mechanism of suppression of cholesterol 7α-hydroxylase and sterol 27-hydroxylase activity, the effects of insulin on their respective levels of messenger RNA (mRNA) and gene transcription were assessed. (tudelft.nl)
  • The decrease in enzyme activities could be explained by a concomitant reduction in the cholesterol 7α-hydroxylase (-76%) and sterol 27-hydroxylase (-62%) mRNA level. (tudelft.nl)
  • Transcriptional activity, as assessed by nuclear runoff assays, was decreased to the same extent, i.e., -60% for cholesterol 7α-hydroxylase and -75% for sterol 27-hydroxylase. (tudelft.nl)
  • We conclude that physiological concentrations of insulin suppress bile acid synthesis by downregulation of cholesterol 7α-hydroxylase and sterol 27-hydroxylase gene transcription, and that this effect is mediated through a direct action of the hormone on the hepatocyte. (tudelft.nl)
  • Similar localization was found for sterol 27-hydroxylase: 2.9-, 2.5-, and 1.7-fold higher enzyme activity, mRNA, and gene transcription, respectively, was found in pericentral hepatocytes. (tudelft.nl)
  • To investigate the biochemical background of this effect, we studied the effects of cafestol and a mixture of cafestol/kahweol/isokahweol (48:47:5 w/w) on bile acid synthesis and cholesterol 7α-hydroxylase and sterol 27-hydroxylase in cultured rat hepatocytes. (tudelft.nl)
  • Dose-dependent decreases of bile acid mass production and cholesterol 7α-hydroxylase and sterol 27-hydroxylase activity were found, showing a maximal reduction of -91%, -79%, and -49% respectively, at a concentration of 20 μg/mL cafestol. (tudelft.nl)
  • We conclude that cafestol suppresses bile acid synthesis by downregulation of cholesterol 7α-hydroxylase and of, to a lesser extent, sterol 27-hydroxylase in cultured rat hepatocytes, whereas kahweol and isokahweol are less active. (tudelft.nl)
  • Ciprofibrate and the PPARα agonist Wy14,643 decreased bile acid synthesis in cultured rat hepatocytes and suppressed cholesterol 7α-hydroxylase and sterol 27-hydroxylase activities, paralleled by a similar reduction of the respective mRNAs. (tudelft.nl)
  • In wild-type mice, ciprofibrate reduced cholesterol 7α-hydroxylase and sterol 27-hydroxylase enzyme activities and mRNA. (tudelft.nl)
  • A decreased bile acid production by PPARα-mediated downregulation of cholesterol 7α-hydroxylase and sterol 27-hydroxylase may contribute to the increased risk of gallstone formation after fibrate treatment. (tudelft.nl)
  • Lund E, Xie C, Kotti T, Turley S, Dietschy J, Russell D. Knockout of the cholesterol 24-hydroxylase gene in mice reveals a brain-specific mechanism of cholesterol turnover. (labome.org)
  • Adrenal glands from adult mice contain mRNAs encoding steroid hydroxylases required to produce corticosterone and aldosterone but not cortisol (little P450c17 mRNA). (nih.gov)
  • Testosterone, along with estrone and estradiol, interact with the estrogen receptor ESR1 (6q25.1, MIM 133430), leading to the activation of the enzyme steroid 5α-reductase type 2 ( SRD5A2 , 2p23, MIM 607306). (aacrjournals.org)
  • Cafestol (20 μg/mL) had no effect on lithocholic acid 6β-hydroxylase mRNA, another enzyme involved in bile acid synthesis. (tudelft.nl)