RESUMO
Objective: To explore the effect of hawthorn proanthocyanidins (HPC) and vitimin C (VC) on liver oxidative stress in insulin-resistance rats. Methods: The insulin-resistance models were prepared by high-fat diet, the weight variations of all rats were tested before and after modeling, so were the contents of fasting blood-glucose and serum insulin after modeling. The colorimetric technique was used to test the concentration of serum ALT, AST, and ALP. The rats in high-fat diet group, who were succeeded in modeling, were divided into model, HPC (56 g/kg), VC (180 g/kg), HPC (56 g/kg) + VC (180 g/kg), and rosiglitazone (122 g/kg) groups. After 12 weeks of continuous administration, these indexes, such as levels of SOD, CAT, GSH-Px, GSH, and MDA in liver homogenates and SOD, GSH-Px, Na+, K+-ATPase, Ca2+, Mg2+-ATPase, and MDA in liver mitochondria, were all tested; RT-PCR was used to test the expression of PPAR-γ mRNA; The Western blotting method was adopted to test the PPAR-γ protein expression. Results: After modeling, the body weight of rats decreased significantly (P<0.05), the concentration of blood, such as glucose, serum insulin ALT, AST, and ALP all increased significantly (P<0.01); The model group was compared with control group, the activities of SOD, CAT, GSH-Px, and GSH were significantly decreased (P<0.01), the levels of glucose, insulin, and MDA increased significantly (P<0.01) in rat liver homogenate, the activities of SOD, GSH-Px, Na+, K+-ATPase, and Ca2+, Mg2+-ATPase were significantly decreased (P<0.01) and MDA level increased significantly (P<0.01) in the liver mitochondria; PPAR-γ mRNA and protein expression decreased significantly in liver tissue (P<0.01). HPC, VC, HPC + VC, and rosiglitazone improved the above indexes, which in the HPC + VC group was better than that in the HPC group and VC group, equivalent to that in rosiglitazone group. Conclusion: Liver oxidative stress which is resulted from insulin-resistance can be improved when HPC and VC are combined.
