Dietary Cholesterol Feeding Suppresses Human Cholesterol Synthesis Measured by Deuterium Incorporation and Urinary Mevalonic...
The main objective of the present work was to characterize the response of human cholesterol synthesis that occurs within the normal range of cholesterol intake. Our results demonstrate modestly reduced cholesterogenesis with increasing dietary cholesterol levels as assessed by two techniques. Metabolic responses to increased dietary cholesterol potentially include reduced endogenous synthesis, decreased absorption, and increased biliary excretion of cholesterol.7 35 Feedback inhibition of cholesterol synthesis has been well described in animals,20 21 whereas the results of investigations in humans have been somewhat equivocal, with downregulation reported in some6 7 35 36 37 38 39 but not all22 23 24 40 41 42 studies. Nestel and Poyser7 fed 2 normolipidemic and 7 hyperlipidemic subjects diets with either 250 or 750 mg/d cholesterol for ,4 weeks. Cholesterol synthesis, as measured by sterol balance, was suppressed at the higher level of dietary cholesterol in 5 of 9 study participants, including ...http://atvb.ahajournals.org/content/16/10/1222.long
Ionizing radiation alters hepatic cholesterol metabolism and plasma lipoproteins in Syrian hamster
PURPOSE: The investigation of the effects of ionizing radiation on hepatic cholesterol metabolism and the concentration and composition of plasma lipoproteins in the male Syrian hamster. MATERIALS AND METHODS: After sublethal whole-body 60Co gamma-irradiation (8 Gy, 1 Gy/min), plasma lipoproteins were separated by density-gradient ultracentrifugation. Activities of hydroxymethylglutarylCoA (HMGCoA) reductase and of cholesterol 7alpha-hydroxylase were measured in hepatic microsomes and the low-density lipoprotein (LDL) receptor mass was determined in hepatic total membranes. Lipid peroxidation in LDL was assessed in vitro as the formation of conjugated dienes at 234 nm. A group of pair-fed animals served as controls as the food intake was markedly decreased with exposure to radiation. RESULTS: Plasma lipid concentrations decreased 2 days post-irradiation and then markedly increased by day 6 post-irradiation; plasma cholesterol was increased by 77% and triglycerides by +207%. ...http://www.irsn.fr/EN/Research/publications-documentation/Publications/DRPH/LRPAR/Pages/Ionizing-radiation-alters-hepatic-cholesterol-metabolism-and-plasma-lipoproteins-in-Syrian-hamster-274.aspx
Dexamethasone regulates bile acid synthesis in monolayer cultures of rat hepatocytes by induction of cholesterol 7α-hydroxylase...
To study the effect of steroid hormones on bile acid synthesis by cultured rat hepatocytes, cells were incubated with various amounts of these compounds during 72 h and conversion of [4-14C]cholesterol into bile acids was measured. Bile acid synthesis was stimulated in a dose-dependent way by glucocorticoids, but not by sex steroid hormones, pregnenolone or the mineralocorticoid aldosterone in concentrations up to 10 microM. Dexamethasone proved to be the most efficacious inducer, giving 3-fold and 7-fold increases in bile acid synthesis during the second and third 24 h incubation periods respectively, at a concentration of 50 nM. Mass production of bile acids as measured by g.l.c. during the second day of culture (28-52 h) was 2.2-fold enhanced by 1 microM-dexamethasone. No change in the ratio of bile acids produced was observed during this period in the presence of dexamethasone. Conversion of [4-14C]7 ...http://www.biochemj.org/content/262/1/341
Cyclosporin A blocks bile acid synthesis in cultured hepatocytes by specific inhibition of chenodeoxycholic acid synthesis |...
Bile acid synthesis, determined by conversion of [4-14C]cholesterol into bile acids in rat and human hepatocytes and by measurement of mass production of bile acids in rat hepatocytes, was dose-dependently decreased by cyclosporin A, with 52% (rat) and 45% (human) inhibition of 10 microM. The decreased bile acid production in rat hepatocytes was due only to a fall in the synthesis of beta-muricholic and chenodeoxycholic acids (-64% at 10 microM-cyclosporin A), with no change in the formation of cholic acid. In isolated rat liver mitochondria, 26-hydroxylation of cholesterol was potently inhibited by the drug (concn. giving half-maximal inhibition = 4 microM). These results suggest that cyclosporin A blocks the alternative pathway in bile acid synthesis, which leads preferentially to the formation of chenodeoxycholic acid. ...http://www.biochemj.org/content/275/2/501
Gut microbiota regulates bile acid metabolism by reducing the levels of tauro-beta-muricholic acid, a naturally occurring FXR...
Bile acids are synthesized from cholesterol in the liver and further metabolized by the gut microbiota into secondary bile acids. Bile acid synthesis is under negative feedback control through activation of the nuclear receptor farnesoid X receptor (http://www.biomedsearch.com/nih/Gut-Microbiota-Regulates-Bile-Acid/23395169.html
Steroid 11-alpha-hydroxylase - Biology-Online Dictionary
Home » Steroid 11-alpha-hydroxylase. steroid 11-alpha-hydroxylase (Science: enzyme) Converts 11-deoxycortisol to 11-alpha cortisol (the 11-alpha isomer of hydrocortisone) Registry number: EC 1.14.99.- ...http://www.biology-online.org/dictionary/Steroid_11-alpha-hydroxylase
Farnesoid X receptor - Wikipedia
FXR is expressed at high levels in the liver and intestine. Chenodeoxycholic acid and other bile acids are natural ligands for FXR. Similar to other nuclear receptors, when activated, FXR translocates to the cell nucleus, forms a dimer (in this case a heterodimer with RXR) and binds to hormone response elements on DNA, which up- or down-regulates the expression of certain genes. One of the primary functions of FXR activation is the suppression of cholesterol 7 alpha-hydroxylase (CYP7A1), the rate-limiting enzyme in bile acid synthesis from cholesterol. FXR does not directly bind to the CYP7A1 promoter. Rather, FXR induces expression of small heterodimer partner (SHP), which then functions to inhibit transcription of the CYP7A1 gene. In this way, a negative feedback pathway is established in which synthesis of bile acids is inhibited when cellular levels are already high. FXR has also been found to be important in regulation of hepatic triglyceride ...https://en.wikipedia.org/wiki/Farnesoid_X_receptor
Intestinal bile acid receptors are key regulators of glucose homeostasis - CNKI学术搜索
In addition to their well-known function as dietary lipid detergents, bile acids have emerged as important signalling molecules that regulate energy homeostasis. Recent studies have highlighted that disrupted bile acid metabolism is associated with metabolism disorders such as dyslipidaemia, intestinal chronic inflammatory diseases and obesity. In particular, type 2 diabetes (T2D) is associated with quantitative and qualitative modifications in bile acid metabolism. Bile acids bind and modulate the activity of transmembrane and nuclear receptors (NR). Among these receptors, the G-protein-coupled bile acid receptor 1 (TGR5) and the NR farnesoid X receptor (FXR) are implicated in the regulation of bile acid, lipid, glucose and energy homeostasis. The role of these receptors in the intestine... in energy metabolism regulation has been recently highlighted. More precisely, recent studies have shown that FXR is important for glucose homeostasis in particular in metabolic disorders such as T2D and ...http://d.scholar.cnki.net/detail/SCUD_U/SCUD4818CC68868271C3F1D73D5A7D92AFB3
ORBi: Browsing ORBi
in European Journal of Biochemistry (1981), 120. 1. Activities of progesterone, testosterone, pregnenolone and dehydroepiandrosterone 16 alpha-hydroxylase are undetectable in the fetal rat liver. During the neonatal period, the four enzymic activities ... [more ▼]. 1. Activities of progesterone, testosterone, pregnenolone and dehydroepiandrosterone 16 alpha-hydroxylase are undetectable in the fetal rat liver. During the neonatal period, the four enzymic activities increase in parallel to the concentration of cytochrome P-450. Until puberty, they develop similarly in male and female rat livers. From the 40th to the 55th day, the four steroid 16 alpha-hydroxylase activities increase rapidly in the male rat liver. The sexual differentiation of the steroid 16 alpha-hydroxylation observed in adult male and female rats takes place around the 55th ...http://orbi.ulg.ac.be/browse?type=author&value=Kremers%2C+Pierre+p000540
OPUS at UTS: Contribution Of A Common Variant In The Promoter Of The 1-Alpha-Hydroxylase Gene (Cyp27B1) To Fracture Risk In The...
Abstract CYP27B1 encodes mitochondrial 1a-hydroxylase, which converts 25-hydroxyvitamin D to its active 1,25- dihydroxylated metabolite. We tested the hypothesis that common variants in the CYP27B1 promoter are associated with fracture risk. The study was designed as a populationbased genetic association study, which involved 153 men and 596 women aged 65101 years, who had been followed for 2.2 years (range 0.15.5) between 1999 and 2006. During the follow-up period, the incidence of fragility fractures was ascertained. Bone ultrasound attenuation (BUA) was measured in all individuals, as were serum 25-hydroxyvitamin D and PTH concentrations; 86% subjects had vitamin D insufficiency. Genotypes were determined for the 1260C[A (rs10877012) and ?2838T[C (rs4646536) CYP27B1 polymorphisms.Areporter gene assay was used to assess functional expression of the 1260C[A CYP27B1 variants. The association between genotypes and fracture risk was analyzed by Coxs proportional hazards model. We found that ...https://opus.lib.uts.edu.au/handle/10453/28733
Abstract 077: Small Heterodimer Partner, An Orphan Nuclear Receptor, Inhibits Cardiac Hypertrophy | Circulation Research
Background: Small heterodimer partner (SHP; NR0B2) is an atypical orphan nuclear receptor lacking DNA binding domain. SHP directly modulates the activities of other nuclear receptors and regulates a variety of cellular events such as cell differentiation, proliferation, and metabolism in various tissues. However, the role of SHP in heart has not yet been elucidated. Thus, in this study, we tried to investigate the functional roles of SHP in heart physiology and in the development of cardiac hypertrophy.. Methods and Results: We observed that SHP knock-out mice elicited cardiac hypertrophic features determined by heart weight to body weight or to tibia length ratios. Fetal genes, such as atrial natriuretic factor (ANF) or beta myosin heavy chain (βMHC) were significantly up-regulated in SHP knockout mice heart. In neonatal rat ventricular cardiomyocytes (NRVCs), phenylephrine (PE) reduced promoter activation of SHP and decreased protein level of SHP. Adenovirus-mediated over-expression of SHP ...http://circres.ahajournals.org/content/113/Suppl_1/A077
Modeling study of some inhibitors of 17,20-lyase, a component of the enzyme 17[alpha]-hydroxylase/17,20-lyase: a novel approach...
A novel molecular modeling study, involving inhibitors bound to a "substrate-heme complex," is described for the binding of steroidal and non-steroidal inhibitors of the 17,20-Lyase component of the enzyme complex 17 alpha-hydroxylase/17,20-lyase to gain further insight into the active site of this enzyme. This novel approach has resulted in the construction of a simple working model using which a number of compounds and their inhibitory activity have been rationalised.. ...http://eprints.kingston.ac.uk/7276/
Synthesis of potential C27-intermediates in bile acid biosynthesis and their deuterium-labeled analogs.
In connection with studies of alternative pathways in bile acid biosynthesis, potential intermediates in a pathway starting with 27-hydroxylation of cholesterol have been prepared in natural and deuterated forms. Established methods were used to prephttp://www.biomedsearch.com/nih/Synthesis-potential-C27-intermediates-in/8475516.html
Most recent papers with the keyword Barrets esophagus | Read by QxMD
AIMS: To investigate expression of nuclear receptors farnesoid X receptor (FXR) and pregnane X receptor (PXR) as a diagnostic tool to improve grading of dysplasia in Barrett's oesophagus patients. METHODS AND RESULTS: Immunostaining was analysed on a total of 192 biopsy samples of 22 Barrett's patients with no dysplasia (ND), 17 with low-grade dysplasia (LGD), 20 high-grade dysplasia (HGD) and 24 with adenocarcinoma (AC). Nuclear FXR expression was observed in 15 of 22 (68%) ND cases versus none of 19 HGD; 3 of 17 (18%); LGD; 5 of 60 (8%) patients with AC (P,0 ...https://www.readbyqxmd.com/keyword/14058
Most recent papers with the keyword Barret's esophagus | Read by QxMD
AIMS: To investigate expression of nuclear receptors farnesoid X receptor (FXR) and pregnane X receptor (PXR) as a diagnostic tool to improve grading of dysplasia in Barrett's oesophagus patients. METHODS AND RESULTS: Immunostaining was analysed on a total of 192 biopsy samples of 22 Barrett's patients with no dysplasia (ND), 17 with low-grade dysplasia (LGD), 20 high-grade dysplasia (HGD) and 24 with adenocarcinoma (AC). Nuclear FXR expression was observed in 15 of 22 (68%) ND cases versus none of 19 HGD; 3 of 17 (18%); LGD; 5 of 60 (8%) patients with AC (P,0 ...https://www.readbyqxmd.com/keyword/14059
Brandeis inventor patents anti-cholesterol formula | BrandeisNOW
Senior Brandeis research scientist Daniel Perlman '68 has discovered a way to make phytosterol molecules from plants dispersible in beverages and foods that are consumed by humans, potentially opening the way to dramatic reductions in human cholesterol levels.. A U.S. patent (number 8,460,738) on the new process and composition was issued on June 11. Phytosterols in plants and cholesterol molecules in animals are highly similar and when both are dispersed together they are attracted to one another. When they mix in the gut of an animal, the cholesterol molecules are competitively inhibited from passing into the blood stream and instead are excreted.. The ability of phytosterols to reduce cholesterol levels in animals has been recognized since the 1950s, but practical application of this knowledge was difficult because phytosterols are not naturally water-soluble, and they are only poorly soluble in fatty substances. Perlman and K.C. Hayes, professor emeritus of biology and former director of the ...http://www.brandeis.edu/now/2013/june/phytosterols.html
KAKEN - Research Projects | Metabolic changes in hepatic cholesterol metabolism by dietary amino acid (KAKENHI-PROJECT-06660154)
Principal Investigator：AOYAMA Yoritaka, Project Period (FY)：1994 - 1995, Research Category：Grant-in-Aid for General Scientific Research (C), Research Field：食品科学・栄養科学https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06660154/
RCSB PDB for 1Q1Z
1Q1Z: Crystal structure of human cholesterol sulfotransferase (SULT2B1b) in the presence of pregnenolone and 3'-phosphoadenosine 5'-phosphate. Rationale for specificity differences between prototypical SULT2A1 and the SULT2BG1 isoforms.http://www.rcsb.org/pdb/explore/biologyAndChemistry.do?structureId=1Q1Z
Identifying your Cholesterol Numbers | Medical Wiki - Medical Jobs, Careers And Information
Tracking down your cholesterol intake nowadays is a must to be sure that you are fit and healthy. There are several ways you can track them and how you count them. Before that let us first define cholesterol, cholesterol is a substance that is waxy in form that the body uses to protect our nerves, produce certain hormones and make cell tissues.. The liver is responsible on making all the cholesterol that the body needs. But cholesterol can also be obtained from foods that we eat. Cholesterol can be found on meats, eggs and dairy products. Too much cholesterol can cause negative impacts to a person's health.. Once the level of cholesterol or cholesterol numbers reaches a high level, the body will store the extra cholesterol in the arteries. These cholesterol buildups in the arteries are called plaque. Once these plaques accumulate over time, it can become hard and make the arteries narrow. Then if there is a large deposit of cholesterol it can block the artery and can also cause splitting ...http://medical-wiki.com/articles/identifying-your-cholesterol-numbers/
Cholesterol & Ways to Lower It - Dr. Fitt Info : Dr. Fitt Info
Need to lower cholesterol? First, you must understand what it is and why it's high. Cholesterol is a waxy molecule produced in the liver. It's a building block used all over the body to make neurotransmitters in your brain, hormones like testosterone/estrogens/progesterone/vitamin D (hormones with a cholesterol base are called "steroid hormones"), and it's a component of every cell membrane in your body.. Remember, you can't pee in just one end of the pool. When you take a drug to lower cholesterol, every system that depends on cholesterol is affected. The side effects of memory loss, muscle pain, liver damage, and type 2 diabetes reflect the fundamental importance of cholesterol as a building block all over the body.. Cholesterol is made in the liver. Sooooo, why is the heart doctor giving you a drug to treat your liver. The reason is that it's not really heart disease that causes "heart attacks". These events, as well as ...http://drfittinfo.com/cholesterol-ways-lower/
triglycerides-207.20,LDL cholesterol-65.26,VLDL cholesterol-41.44
... please advise me Hello Swati, I read your message carefully and understood your medicalhttps://www.all-about-lowering-cholesterol.com/triglycerides20720ldl-cholesterol6526vldl-cholesterol4144.html
Cholesterol Support - Health Concerns - Nutrition Express
Low prices on Cholesterol Support! Support healthy cholesterol levels already within the normal range*. Cholesterol can be both good and bad. LDL is usually referred to as bad cholesterol and HDL is good cholesterol. Numerous natural ingredients may help support healthy cholesterol levels already within the normal range.https://www.nutritionexpress.com/health+concerns/cholesterol+support/nutiva+red+palm+oil+15+ounces.aspx
Cholesterol Metabolism By Amr S. Moustafa, M.D.; Ph.D. - ppt download
Outlines Overview and Functions Liver cholesterol pool Structure and Types Synthesis and Regulation Bile acids and salts Enterohepatic circulationhttp://slideplayer.com/slide/3376785/
NR5A2 + LRH1 ELISA & Assay Kits
Order NR5A2 + LRH1 ELISA Kits for many Reactivities. Chicken, Human, Mouse and more. Compare NR5A2 + LRH1 ELISA Kits and find the right product on antibodies-online.com.http://www.antibodies-online.com/nuclear-receptor-transcription-pathway-pathway-23/nr5a2-+-lrh1-elisa-kit-9091/