Dietary calcium decreases plasma cholesterol level only in female but not in male hamster fed a high cholesterol diet / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the effect of dietary calcium on plasma lipoprotein profile in castrated and ovariectomized hamsters.</p><p><b>METHODS</b>Male, castrated, female and ovariectomized hamsters (n=36 each group) were randomly divided into three sub-groups (n=12) and fed one of the three diets containing 0, 2, and 8 g calcium per kg diet for a period of six weeks. Changes in plasma lipoprotein profile were monitored at the end of week 0, 3 and 6.</p><p><b>RESULTS</b>Plasma total cholesterol (TC), non-high density lipoprotein cholesterol (non-HDL-C), triacylglycerols (TG) and TC/HDL-C were decreased only in intact female and ovariectomized hamsters. In contrast, three levels of dietary calcium had no effect on lipoprotein profiles in both intact male and castrated hamsters.</p><p><b>CONCLUSION</b>Beneficial modification of lipoprotein profile by dietary calcium was gender-dependent at least in hamsters.</p>

Red yeast rice increases excretion of bile acids in hamsters / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the hypocholesterolemic activity of red yeast rice (RYR) and its underlying mechanism.</p><p><b>METHODS</b>Three groups of hamsters were fed either the control diet or one of the two experimental diets containing by weight 0.1% RYR (0.1RYR) or 0.3% RYR (0.3RYR). Blood (0.5 mL) was collected from the retro-orbital sinus into a heparinized capillary tube at the end of week 0, 3, and 6. Plasma lipoproteins were measured using enzymatic kits, while fecal neutral and acidic sterols were quantified using a gas-liquid chromatography.</p><p><b>RESULTS</b>Plasma total cholesterol was reduced by 12% in 0.1RYR group and by 18% in 0.3RYR group compared with the control value. Similarly, plasma triacylglycerol was decreased by 11% in 0.1RYR group and by 24% in 0.3RYR group. Western blotting analysis demonstrated that RYR had no effect on sterol regulatory element binding protein 2, liver X receptor, 3-hydroxy-3-methylglutary-CoA reductase, LDL receptor, and cholesterol-7alpha-hydroxylase. HPLC analysis confirmed that RYR contained 0.88% monacolin K. It was recently found that RYR supplementation increased excretion of fecal acidic sterols by 3-4 folds compared with the control value.</p><p><b>CONCLUSION</b>Hypocholesterolemic activity of RYR is mediated at least partially by enhancement of acidic sterol excretion.</p>