Effect Of Berberine And Taurine On Insulin Receptor Substate-1 Gene MRNA Expression In Skeletal Muxules Of Rats Model Of Insulin Resistance

Objective: To investigate the effects of berberine and taurine on insulin receptor substrate-1(IRS-1) gene mRNA expression in skeletal muscles of high fat rats model of insulin resistance(IR)and to study their effects on blood glucose, blood lipids, insulin levels, insulin sensitivity index(ISI)and body weight.Methods: 40 IR rat models induced by high fat diet of 30 days were randomly distributed into five groups(8 rats/group): berberine group;taurine group; berberine combined with taurine (combine)group; metformin group;model group,and meanwhile compared with the normal group(8 rats fed with normal diet). After intervention respectively for 30 days,the body weight,fasting blood glucose (FBG),fasting insulin(FINS),total cholesterol(TC),triglycerides(TG), high–density lipoprotein cholesterol(HDL-C),Low-density lipoprotein cholestero(LDL-C) of all the rats were measured. ISI was calculated. The expression level of IRS-1 mRNA of skeletal muscles was determined by used reverse trascription polymerase chain reaction(RP-PCR).Result: 1.High-fat diets (59% calories from fat)can induce IR in rats. compaired with control group, FBG,FIN,TG,TC,LDL-C of the model group increased and ISI decreased. The expression of IRS-1 mRNA of skeletal muscles decreased significantly .2.Compaired with the model group, ISI increased and the expression of IRS-1 mRNA in skeletal muscles increased in berberine group,taurine group,combine group,metformin group.the combine group was better.3. The decrease of TG,TC ,LDL-C and the increase of HDL-C in combine group and taurine group were better obviously than other group.4.There was no significant difference between the parameters of berberine group and taurine group mentioned above.Conclusion: Berberine and taurine have good effect of lowering IR in rats induced by high-fat diet and can up-regulate the expression of IRS-1mRNA in skeletal muscles . Application of combining Berberine with taurine has the best effect. Up-regulation of the expression of IRS-1 mRNA in skeletal muscles seems to be one of the mechanisms to ameliorate IR.