Division of Cardiology, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
PLoS One. 2011;6(11):e27437. doi: 10.1371/journal.pone.0027437. Epub 2011 Nov 16.
To determine the efficacy and underlying mechanism of Astragalus polysaccharides (APS) on plasma lipids in hypercholesterolemia hamsters. The effect of APS (0.25 g/kg/d) on plasma and liver lipids, fecal bile acids and neutral sterol, cholesterol absorption and synthesis, HMG-CoA reductase activity, and gene and protein expressions in the liver and small intestine was investigated in twenty-four hypercholesterolemia hamsters. Treatment periods lasted for three months. APS significantly lowered plasma total cholesterol by 45.8%, triglycerides by 30%, and low-density lipoprotein-cholesterol by 47.4%, comparable to simvastatin. Further examinations revealed that APS reduced total cholesterol and triglycerides in the liver, increased fecal bile acid and neutral sterol excretion, inhibited cholesterol absorption, and by contrast, increased hepatic cholesterol synthesis and HMG-CoA reductase activity. Plasma total cholesterol or low-density lipoprotein-cholesterol levels were significantly correlated with cholesterol absorption rates. APS up-regulated cholesterol-7α-hydroxylase and LDL-receptor gene expressions. These new findings identify APS as a potential natural cholesterol lowering agent, working through mechanisms distinct from statins.
为了确定黄芪多糖（APS）对高胆固醇血症仓鼠血浆脂质的疗效和潜在机制。研究了 APS（0.25 g/kg/d）对 24 只高胆固醇血症仓鼠的血浆和肝脏脂质、粪便胆汁酸和中性固醇、胆固醇吸收和合成、HMG-CoA 还原酶活性以及肝脏和小肠中的基因和蛋白质表达的影响。治疗期持续三个月。APS 可显著降低血浆总胆固醇 45.8%、甘油三酯 30%和低密度脂蛋白胆固醇 47.4%，与辛伐他汀相当。进一步的检查表明，APS 降低了肝脏中的总胆固醇和甘油三酯，增加了粪便胆汁酸和中性固醇的排泄，抑制了胆固醇的吸收，相反，增加了肝内胆固醇的合成和 HMG-CoA 还原酶的活性。血浆总胆固醇或低密度脂蛋白胆固醇水平与胆固醇吸收率显著相关。APS 上调了胆固醇-7α-羟化酶和 LDL 受体基因的表达。这些新发现表明 APS 是一种有潜力的天然降胆固醇药物，其作用机制与他汀类药物不同。
