白背三七对胰岛素抵抗大鼠肝脏胰岛素受体表达的影响

Effect of Gynura divaricata (L.) DC. on insulin receptor gene expression in liver in insulin resistance rats

目的 :观察白背三七对胰岛素抵抗大鼠肝脏胰岛素受体(InsR)表达的影响,探讨其改善胰岛素抵抗的作用机制。方法 :采用高糖高脂饲料喂养加小剂量链脲佐菌素(STZ)腹腔注射的方法建立胰岛素抵抗大鼠模型,6周后测定糖耐量(GTT),留取空腹血清测定血糖(FPG)、糖化血红蛋白(GHb)和胰岛素(FINS)水平,计算胰岛素敏感指数(ISI)及胰岛素抵抗指数(HOMAIR),RT-PCR法检测肝细胞膜胰岛素受体(InsR)mRNA表达。结果:白背三七2g/kg、白背三七1g/kg均能显著改善胰岛素抵抗大鼠GTT;白背三七2g/kg、白背三七1g/kg均能显著降低FPG、GHb、FINS和HOMA-IR,显著增加ISI,明显上调肝细胞膜InsR mRNA的表达。结论:白背三七对大鼠胰岛素抵抗有明显的改善作用,其作用机制可能与上调InsR mRNA的表达有关。

Aim： To observe the effect of Gynura divaricata（ L.） DC.（ GDD） on insulin receptor（ InsR） gene expression in liver in insulin resistance rats and explore its molecular mechanism of ameliorating insulin resistance. Methods： The model of insulin resistance rats were induced by feeding high glucose-lipoids animal feeds and injecting low dose streptozotocin（ STZ） intraperitoneally. After 6 weeks,glucose tolerance test（ GTT） was measured,then fasting plasma glucose（ FPG）,glycosylated hemoglobin（ GHb） and fasting serum insulin（ FINS） were measured,insulin sensitivity index（ ISI） and homestasis model assessment for insulin resistance（ HOMA-IR） were calculated,the expression level of InsR mRNA in liver was determined by used reverse trascription polymerase chain reaction（ RT-PCR）. Results ： 2g / kg GDD extract and 1g / kg GDD extract could significantly ameliorate GTT of insulin resistance rats（ P 〈 0. 01）,2g / kg GDD extract and 1g / kg GDD extract could significantly lower FPG,GHb,FINS and HOMA-IR（ P 〈 0. 01）,higher ISI（ P 〈 0. 01）,remarkably up-regulat the expression level of InsR mRNA in liver（ P 〈 0. 05 or P 〈 0. 01）. Conclusions： The GDD extract had an obvious ameliorative effect on insulin resistance rats,its molecular mechanism might be related with its ability of up-regulating the expression level of InsR mRNA.