Objective: To observe the effects of Bushen Tongmai Recipe (, BSTMR) on mRNA and protein expressions of protein kinase B alpha (PKB alpha) in hepatic, adipose, muscular, and ovarian tissues of polycystic ovary (PCO) rats with insulin resistance (IR) and to explore the possible molecular mechanism of BSTMR in treating IR and ovulation dysfunction.
Methods: Female 22-day-old SD rats were injected subcutaneously with sodium prasterone sulfate (9 mg.100g(-1).d(-1)) for 20 days and fed with high-fat diet for 80 days to induce PCO rats with IR. Then, the PCO rats were randomly divided into the model group (n=23) and the treated group (n=21). The treated group was administered with BSTMR for 2 weeks. Meanwhile, a group with 15 rats of the same age was used as the control group. The histological changes in the ovaries were examined. Fasting blood glucose (FBG) was determined by the glucose oxidase method. Serum fasting insulin (Fins) was determined by radioimmunoassay (RIA). The mRNA level of PKBalpha was measured by reverse transcription polymerase chain reaction (RT-PCR). Immunohistochemistry staining and Western blot analysis were employed to detect the protein expression in target tissues.
Results: Compared with the control group, the ovaries in the model group showed multiple follicular cysts, levels of FBG and Fins in the model group increased markedly (P<0.05 or P<0.01, respectively), and the insulin sensitive index (ISI) decreased obviously (P<0.01). The mRNA and protein expressions of PKBalpha in target tissues in the model group were dramatically lower than those in the control group (P<0.05 or P<0.01). Compared with the model group, the stratum granulosum of the ovarian follicle in the treated group increased markedly, the level of Fins in the treated group decreased obviously (P<0.01), ISI in the treated group improved markedly (P<0.01), and the mRNA and protein expressions of PKBalpha in target tissues of the treated rats were elevated significantly (P<0.05 or P<0.01).
Conclusion: BSTMR could improve IR and ovulation dysfunction in PCO rats with IR, and its molecular mechanisms might be closely related with the elevation of mRNA and protein expressions of PKBalpha in target tissues of PCO rats with IR.