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Cholesterol Absorption (cholesterol + absorption)
Terms modified by Cholesterol Absorption Selected AbstractsHypocholesterolemic and Anti-Obesity Effects of Saponins from Platycodon grandiflorum in Hamsters Fed Atherogenic DietsJOURNAL OF FOOD SCIENCE, Issue 8 2008H.L. Zhao ABSTRACT:, Platycodins, a group of saponin glycosides from Platycodon grandiflorum, are believed to possess anti-obesity and cholesterol-lowering properties. The aim of the present study was to investigate whether dietary platycodins affect plasma, hepatic, or fecal cholesterol concentrations, as well as cholesterol absorption and fractional synthesis rates in a dose-dependent manner. Golden Syrian hamsters (n= 45) were fed atherogenic (0.25% cholesterol) diets enriched with platycodins in the forms of either aqueous extracts (containing 0.3% to 0.5% of platycodins of diet mass) or crude saponins fractions (containing 0.9% to 1.0% of platycodins of diet mass) for 28 d. {3, 4},13C-cholesterol and 2H2O tracers were administered on days 26 and 28 to assess cholesterol absorption and biosynthesis, respectively. After platycodin intervention, total cholesterol concentrations in plasma and liver were reduced (P < 0.05) by 13% to 28% and 41% to 79%, respectively, whereas cholesterol concentrations in feces were increased (P < 0.05) up to 2.5-fold compared to controls. Platycodin feeding increased (P < 0.001) cholesterol absorption up to 60%, but not cholesterol synthesis. These results suggest that platycodin-enriched diets can lower circulating and whole body cholesterol contents, and thus reduce the risk of cardiovascular diseases through mechanisms independent from cholesterol absorption or synthesis. [source] Expression levels of genes for ATP-binding cassette transporters and sterol 27-hydroxylase in liver and intestine of baboons with high and low cholesterolemic responses to dietary lipidsJOURNAL OF MEDICAL PRIMATOLOGY, Issue 3 2005Rampratap S. Kushwaha Abstract:, Baboons with high and low lipemic responses to dietary lipids differ in intestinal cholesterol absorption and hepatic cholesterol metabolism. ATP-binding cassette (ABC) transporters play an important role in cholesterol absorption and hepatic cholesterol metabolism. Using frozen tissues from high- and low-responding baboons maintained on the cholesterol and fat-enriched diet, we determined the relative expression of ABCA1, ABCG5, ABCG8, and 27-hydroxylase genes in the liver and intestine using TaqMan® real-time polymerase chain reaction. There was no consistent difference in the expression of ABC-transporters and 27-hydroxylase in the intestine between high- and low-responding baboons. However, hepatic expression of sterol 27-hydroxylase, ABCG5, and ABCG8 was higher in low-responding baboons than in high-responding baboons. There was also a significant correlation between the expression of sterol 27-hydroxylase and ABCG5, and ABCG8 in both the liver and the intestine. These results suggest that differences in hepatic lipid metabolism but not in cholesterol absorption between high- and low-responding baboons observed previously may be mediated by the differences in the expression levels of 27-hydroxylase, ABCG5, and ABCG8. [source] Inhibition of intestinal absorption of cholesterol by surface-modified nanostructured aluminosilicate compoundsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 7 2009Pavel Gershkovich Abstract The aim of this work was to assess the ability of aqueous suspensions of surface-modified nanostructured aluminosilicate (NSAS) compounds to reduce the intestinal absorption of cholesterol in a rat model. The rats were divided into 10 treatment groups which included several NSAS compounds at various doses, ezetimibe at 10 mg/kg, stigmastanol at 50 mg/kg, and normal saline. All compounds and controls were independently administered by oral gavage and then a mixture of [3H]cholesterol and cold cholesterol in 10% Intralipid® was immediately administered orally to the animals. Systemic blood was sampled and the concentration of cholesterol in plasma was determined by means of radioactivity. Protonation of NSAS using an ion-exchange column resulted in significant inhibition of cholesterol absorption relative to the control group (31.5% and 38.6% reduction in absorption of cholesterol for 50 and 100 mg/kg doses, respectively). Other surface-ion modifications of NSAS compounds did not show significant effect on intestinal cholesterol absorption. The inhibition of cholesterol absorption by ezetimibe was superior and by stigmastanol was equal to the effect of protonated NSAS in the doses investigated in this study. In conclusion, protonated NSAS material seems to inhibit significantly the intestinal absorption of dietary cholesterol in a rat model. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2390,2400, 2009 [source] Effects of microcrystalline plant sterol suspension and a powdered plant sterol supplement on hypercholesterolemia in genetically obese Zucker ratsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 12 2003Jari Summanen ABSTRACT Because dietary fat appears to be an effective vehicle for dispensing plant sterols into the diet, a special plant-sterol-containing ingredient has recently been developed. This ingredient is a plant sterol suspension in oil in which the sterols are in microcrystalline form. The objective of the present study was to analyse the cholesterol-lowering effects and safety of two different plant sterol preparations, an orally administered microcrystalline plant sterol suspension (MPS) in rapeseed oil and a powdered plant sterol supplement, in obese Zucker rats. Dietary plant sterol supplements (0.5%, w/w) were given concurrently with a high cholesterol diet (HCD, 1% cholesterol and 18% fat, w/w). No significant changes in serum triglyceride, blood glucose, serum glutamate oxaloacetic transaminase and glutamic pyruvic transaminase values or body and liver weights were observed. The powdered plant sterol supplement lowered the serum cholesterol by 25% (P< 0.05) and the MPS diet by 35% (P< 0.001) compared with HCD by the end of the 12-week experiment. Interestingly, the plant sterol supplements also produced a marked reduction in serum ubiquinone levels, suggesting a possible effect on isoprene synthesis. Unlike the powdered plant sterol, both MPS and plain rape-seed oil decreased the serum baseline diene conjugation values, suggesting that they protect against oxidative stress-induced lipid peroxidation in rats. This lipid peroxidation diminishing effect is probably due to some antioxidative components in rapeseed oil. These findings indicate that an unesterified plant sterol, such as the microcrystalline suspension in oil, effectively prevents cholesterol absorption in obese Zucker rats. [source] [2H/H] Isotope ratio analyses of [2H5]cholesterol using high-temperature conversion elemental analyser isotope-ratio mass spectrometry: determination of cholesterol absorption in normocholesterolemic volunteersRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 3 2004Jean-Philippe Godin This paper validates the use of high-temperature conversion elemental analyser isotope-ratio mass spectrometry (TC-EA/IRMS) for measuring the [2H/H] enrichment of plasma [2H5]cholesterol. From a molecular point of view, the free cholesterol is initially separated from plasma by thin-layer chromatography (TLC) and then injected onto the TC-EA reactor which converts cholesterol molecules into CO and H2 gases. The slope of the curve of the experimental mole percent excess (MPE(exp.)) versus MPE(theor.) was very close to 1, demonstrating that no significant isotopic fractionation was observed during all processing of the samples (i.e., isolation of plasma free cholesterol by TLC and pyrolysis in the TC-EA reactor). Excellent linearity (r2,=,0.9994, n,=,4) of , (,) of [2H/H] isotopic measurements versus mole percent (MP) was assessed over the range 0 to 0.1 MP. The precision of the [2H/H] measurement, evaluated with two calibration points processed with TLC, was ,2HV-SMOW,=,,192.5,±,3.4, and ,2HV-SMOW,=,,136.9,±,2.9,. The standard deviations of the within-assay and between-assay repeatabilities of the analytical process, evaluated using the quality control (QC) of plasma samples, were 4.6 and 6.1,, respectively. Plant sterols are known to reduce cholesterol absorption and therefore were used as a positive control in a clinical study performed with normocholesterolemic volunteers. This present method produces biological results consistent with those already reported in the literature. Copyright © 2004 John Wiley & Sons, Ltd. [source] Cholesterol metabolism in 8 to 12-year-old children born preterm or at termACTA PAEDIATRICA, Issue 5 2003M Mortaz Studies in animals have indicated that cholesterol metabolism is susceptible to manipulation by diet and growth in early life. In humans, low birthweight has been associated with increased risk of coronary heart disease. Aim: To establish whether plasma lipids and indicators of cholesterol absorption, synthesis and breakdown differ in children born preterm and at term. Methods: Plasma total cholesterol, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, triacylglycerols, apolipoprotein A1, apolipoprotein B, lathosterol (indicator of cholesterol synthesis), campesterol (indicator of cholesterol absorption), 7-, hydroxycholesterol (indicator of cholesterol breakdown) were measured in up to 407 children born preterm and 36 children born at term. Results: Children born preterm had lower cholesterol synthesis (p= 0.002) and lower cholesterol breakdown (p < 0.001) than those born at term, but their plasma cholesterol concentration was not significantly different. After adjusting for current size, birthweight and gestational age were significantly related to plasma lathosterol and 7-, hydroxycholesterol. However, when both birthweight and gestational age were adjusted, only gestational age remained significant. There were no significant differences in plasma campesterol between the two groups. Conclusion: Being born preterm may have a long-term effect on cholesterol metabolism in children 8,12 y later. Those born prematurely had lower cholesterol synthesis and breakdown, but their plasma cholesterol concentration was similar at this age. These parameters need to be studied in older cohorts. [source] | |||||||||||||