The Role Of The Resvertrol To The Homocysteine Metabolism On Insulin Resistance Model

Objective To set up the insulin resistance model, and use the resveratrol to intervene, in order to investigate the metabolic mechanism of homocysteine change for SD rats with insulin resistance.Methods There are forty healthy mice, ten mice which were fed by normal food were made as control group, Thirty mice were made to insulin resistance model with diet by high fat and sugar and gavage by high fat for3months. After making sure the success of insulin resistance model, the rats were randomly divided into the insulin resistance group (n=10)and the resveratrol intervention group (n=10). Normal food was fed in the insulin resistance group for one months; The resveratrol intervention group was fed by normal food and gavage by resveratrol (30mg/kg/d)for eight weeks; the concentrations of homocysteine, glucose, insulin, total cholesterol and triglyceride were measured in the fasting state. At the same time, the insulin resistance index (ISI) was calculated. The expressions of methylenetetrahydrofolate reductase (MTHFR), cystathionineβsynthase (CBS) and methionine synthetase (MTR) were detected by Immunohistochemical, RT-PCR and Western Blot in the rat liver tissue.Results The concentrations of the blood glucose and blood insulin in the insulin resistance group were higher than that in the control group (P<0.05), the insulin resistance index was increased, so the insulin resistance model was successed. The concentrations of triglyceride and homocysteine were increased (P<0.05). However, the concentration of total cholesterol was no statistical significance (P>0.05). The protein and mRNA expressions of MTHER and CBS in insulin resistance group were lower compared with the control group by RT-PCR, Western Blot and immunohistochemical staining(P<0.05). However, the expression of MTR protein and mRNA were not difference between the insulin resistance group and the control group (P>0.05).The concentrations of the blood glucose and blood insulin in the resveratrol intervention group were lower than that in the insulin resistance group (P<0.05). The concentrations of homocysteine were decreased (P<0.05). However, the concentration of total cholesterol and triglyceride were no statistical significance (P>0.05). The protein and mRNA expressions of MTHER and CBS in the resveratrol intervention group were higher compared with the insulin resistance group by RT-PCR, Western Blot and immunohistochemical staining(P<0.05). However, the expression of MTR protein and mRNA were not difference between the resveratrol intervention group and the insulin resistance group (P>0.05).Conclusion The homocysteine concentration is higher in the condition of insulin resistance, which may related to decrease with the expression of MTHER and CBS in metabolic transformation of homocysteine. resveratrol can improve the expression of the MTHFR and CBS which participate to the metabolism of homocysteine, thus it can play a protective role in insulin resistance.