白藜芦醇对高糖高脂饲料大鼠胰岛素敏感性的影响

目的研究白藜芦醇对高能量饮食大鼠胰岛素敏感性的影响。方法清洁级雄性Wistar大鼠35只,随机分为对照组(正常Cont和高糖高脂对照组HFG)和低、中、高白藜芦醇剂量组(HFG+R1,2,3)。12W后分别进行口服葡萄糖耐量试验和胰岛素耐量试验。13W末,断头处死,测空腹血糖和血胰岛素,计算稳态评估胰岛素抵抗指数(HOMA-IR指数)。实时荧光定量PCR技术检测主动脉磷脂酰肌醇3激酶p85αmRNA水平变化。结果与高糖高脂组比,白藜芦醇显著降低大鼠体重,调节血脂(P<0.05)。白藜芦醇还可显著降低大鼠血胰岛素水平和HOMA-IR指数,改善高糖高脂饮食诱导的大鼠葡萄糖耐量和胰岛素耐量异常(P<0.05)。高糖高脂饮食使大鼠p85αmRNA表达降低,中、高剂量的白藜芦醇则可遏制高糖高脂的有害作用(P<0.05)。结论白藜芦醇可提高高糖高脂饮食大鼠胰岛素敏感性,预防胰岛素抵抗的发生,其机制可能与调节主动脉PI3K p85αmRNA水平有关。

EFFECTS OF RESVERATROL ON INSULIN SENSITIVITY OF RATS FED WITH HIGH-FAT/GLUCOSE FEED

Objective To investigate the effect of resveratrol on plasma insulin sensitivity of rats fed with high calories feed.Method Thirty five male Wistar rats were randomly allocated to five groups(7 rats in each group): control group(Con),high-fat/glucose groups(HFG) and resveratrol-treated groups(HFG+R).Oral glucose tolerance test(OGTT) and insulin tolerance test(ITT) were used in all groups after 12w.After the 13th week,the rats were killed and fasting plasma glucose and insulin were measured,and homeostasis model assessment-insulin resistance(HOMA-IR) index of each group calculated.Phosphatidylinositol 3-kinase p85α mRNA was detected by real-time quantitative PCR.Results Compared with HFG group,the body weight,total cholesterol and total triglyceride were significantly decreased after treatment of resveratrol(P<0.05),so fasting plasma insulin,HOMA-IR index,OGTT and ITT were obviously ameliorated in resveratrol groups.Besides,the p85α mRNA was increased evidently in mid and high dose resveratrol groups compared with HFG group(P<0.05).Conclusion Resveratrol markedly improved insulin sensitivity,and decreased the incidence of insulin resistance in rats fed with high-fat/glucose feed.Its molecular mechanism may be related to the level of p85α mRNA in artery.