The Effect Of Metformin On Polycystic Ovarian Syndrome Luteinizing Granulosa Cells In IRS-1 And P38 And Phosphorylation Expression

Background:Polycystic ovarian syndrome(PCOS)is a common gynecological endocrine disease,often accompanied by insulin resistance and the metabolism abnormality.Studies have shown roughly 60% to 70% of PCOS patients exist IR.The combination of Insulin receptor and IRS-1 proved a signaling cascades,activation of MAPK pathway and PI3 K pathway.The IRS-1 was identified to have kinase activity and serine kinase activity,when abnormal expression of insulin receptor,then explore MAPK pathway and PI3 K pathway transduction molecules after insulin receptor of PCOS.Abnormal activation of MAPK pathway mitogenic pathway lead to PCOS patients were possible easily bring about ovarian hyper-stimulation reaction and IR.P38 is an important signal molecular in MAPK pathway,plays an important role in insulin resistance.Granulosa cells(Granulosa cells,GC)promote oocyte maturation.PCOS patients exist IR metabolic disturbances did result in decreased tissue insulin sensitivity,but to improve the accuracy it will still need more studies.Objective: A1 l granulose cells detecting different doses of Metformin were examined for p-IRS-1 and p-p38 protein expression by Western blot.Then explore transduction molecules after insulin receptor of PCOS.Methods: Ovarian granulosa cells were collected from PCOS patients exist IR who undergoing in vitro fertilization / intracytoplasmic sperm injection embryo transfer(IVF/ICSI-ET)in Department of Reproductive Medicine,Affiliated Hospital of Medical College of Qingdao University.We isolated and purified luteinizing granulosa cells from PCOS patients in vitro(n=30),added different dosages of Metformin(ultimate density: 0.01 m M,0.1m M and 1m M),set as PCOS+IN group(n=15),without Met for PCOS group(n=15).Human luteinizing granulosa cells of non-PCOS patients as the normal control group(n=15).We examined p-IRS-1and p-P38 protein expression of ovarian granulosa cells by Western Blot.We conducted a meta-analysis of studies compare with the two group infertility years,assayed the serum PRL(Prolactin),FSH(Follicle stimulating hormone),LH(Luteinizing hormone),T(Testosterone),BMI(Body mass index).Results:(1)The levels of serum LH and TT in PCOS patients were higher than those in the control group,with a significant difference(P < 0.05).(2)The protein expression levels of p-P38 and p-IRS-1 in the granulosa cell of PCOS patients were higher than the normal control group,the difference was statistically significant(P < 0.05).(3)After treatment with different concentrations of Met,the expression of p-P38 protein was still higher in PCOS patients(PCOS+IN group)than that of the normal control group,but lower than the PCOS group,the differences were statistically significant(P < 0.05).(4)After Met treatment in 0.01 m M-dosage and 0.1m M-dosage,the expression of IRS-1 was significantly lower than that in the PCOS group(P < 0.05).But there was no significant difference in IRS-1 protein expression between two groups after Met treatment in 1m M-dosage(P < 0.05).Conclusion: MAPK pathway in ovarian granulosa cells of PCOS patients were activated,the expression on level p-IRS-1 and p-P38 are increasing in the MAPK pathway,PCOS patients were possible easily bring about ovarian hyper-stimulation reaction and IR during IVF-ET.Met may decrease the expression of P38 and IRS-1 in ovarian granulosa cells,improve PCOS patients which have existed insulin resistance.On Metformin treatment in patients with PCOS can improve insulin sensitivity in ovarian granulosa cells,inhibited P38 and IRS-1 negative feedback on the role of the MAPK pathway and reduce the PI3 K pathway activity,improve the status of the IR.