Preliminary Research Of The Molecular Mechanism Of Ovarian Local Insulin Resistance In PCOS Patients.

Preliminary research of the molecular mechanism of ovarian local insulin resistance in PCOS patients.OBJECTIVE: Researchers have lately found that, compared to normal ovulation control group, the expression level of Insulin receptor substrate-1 (IRS-1) and Insulin receptor substrate-2 (IRS-2) do not change in follicular cells of antral follicles from PCOS patients. But the expression level of IRS-1 increases and that of IRS-2 decreases in PCOS luteinizing granulose cells. To find out the reason of this transition, we studied the impact of Gonadotrophin (Gn) and Rosiglitazone on the mRNA expression of IRS-1 and IRS-2 in luteinizing granulosa cells from PCOS patients.METHODS: Luteinizing granulosa cells from 9 PCOS patients and 10 patients with normal menstruation as controls were cultured. Granulosa cells collected from each patient were divided into several groups and treated with 0.9% sodium chloride, rhFSH, HCG or Rosiglitazone (PCOS group) respectively for 48h. We determined their impact on IRS-1 and IRS-2 mRNA expression by semi-quantitative RT-PCR.RESULT:(1) Compared with the control, IRS-1 mRNA expression of PCOS granulosa cells increased and IRS-2 mRNA expression was lower (P<0.05). (2) rhFSH had no effect on IRS-1 and IRS-2 mRNA expression of PCOS granulosa cells (P>0.05). (3) HCG increases mRNA levels of IRS-1 (P<0.05) but not IRS-2 in PCOS cells. (4) Rosiglitazone increased IRS-2 and decreased IRS-1 mRNA expression of luteinizing granulosa cells from PCOS patients (P<0.05).CONCLUSION:(1) There is local insulin resistance in ovary of PCOS patients. (2) Increasing level of LH in PCOS cells may participate the local insulin resistance mechanism of PCOS. (3) Rosiglitazone can improve the selective insulin resistance of PCOS luteinizing granulosa cells.