烟籽油对高胆固醇血症大鼠胆固醇代谢的影响

Effects of tobacco seed oil on metabolism of cholesterol in rats with hypercholesterolemia

为研究烟籽油对大鼠血清胆固醇水平及肝脏中胆固醇代谢相关调控基因表达的影响,以高胆固醇饲料喂养的大鼠为动物模型,随机分为对照组(空白对照、模型对照、鱼油对照)和实验组(低、中、高剂量烟籽油),测定血清TC、TG、HDL-C和LDL-C水平;RT-PCR检测肝脏中胆固醇代谢相关调控基因表达;肝组织切片染色,观察大鼠肝细胞脂肪变性。结果表明:1烟籽油能有效降低高胆固醇血症大鼠血清TC和LDL-C水平,降低动脉硬化指数,改善肝细胞脂肪变性;2烟籽油可使高胆固醇血症大鼠肝脏中HMGCR基因下调表达,LDLR基因上调表达。因此,烟籽油具有明显的降低胆固醇作用,其机制可能是调控了肝脏中胆固醇代谢相关基因的表达。

In order to investigate the effects of tobacco seed oil on serum cholesterol level and expressions of regulatory genes related to cholesterol metabolism in livers of rats,the levels of total cholesterol（TC）,triacylglycerol（TG）,high density lipoprotein cholesterol（HDL-C） and low density lipoprotein cholesterol（LDL-C）in serum were determined by using rats fed with a high level cholesterol diet as animal models. The rats were randomly divided into control groups（blank control group,model control group,fish oil control group） and experimental groups（three groups fed with tobacco seed oil at low,middle and high doses,separately）. The expressions of regulatory genes related to cholesterol metabolism in livers of rats were measured with real-time PCR method. Liver tissues were sliced and stained to observe the steatosis of hepatic cells of rats. The results showed that：1）Tobacco seed oil effectively reduced the levels of TC and LDL-C in serum and atherogenic index of rats,improved hepatic steatosis. 2） Tobacco seed oil down-regulated the expression of HMGCR gene and up-regulated the expression of LDLR gene in livers of rats with hypercholesterolemia. Therefore,tobacco seed oil has a significant effect of lowering total cholesterol,the mechanism might be actioned by regulating the expressions of genes related to cholesterol metabolism in livers.