罗格列酮对多囊卵巢综合征患者卵巢黄素化颗粒细胞胰岛素受体底物1和2蛋白表达及酪氨酸磷酸化的影响

Effect of rosiglitazone on tyrosine phosphorylation and protein expression of insulin receptor substrate 1 and 2 in ovarian luteinizing granulosa cells from patients with polycystic ovarian syndrome

目的:研究罗格列酮对多囊卵巢综合征(PCOS)患者卵巢黄素化颗粒细胞胰岛素受体底物-1(IRS-1)和IRS-2蛋白表达及酪氨酸磷酸化的影响。探讨罗格列酮改善PCOS卵巢局部胰岛素抵抗的作用。方法:收集行IVF-ET治疗的11例PCOS患者(PCOS组)和15例排卵正常患输卵管性不孕患者(对照组)促排卵后黄素化颗粒细胞行体外培养,分别用不同浓度罗格列酮(0、1、10、100、1000、10000nmol/L)处理细胞48h,采用RT-PCR、免疫印迹(Western blotting)及免疫沉淀法分别检测卵巢黄素化颗粒细胞IRS-1和IRS-2mRNA的表达、蛋白含量及酪氨酸磷酸化水平。结果:(1)与对照比较,PCOS组黄素化颗粒细胞IRS-1mRNA表达及蛋白含量显著增加(P<0.05),IRS-2mRNA表达及蛋白含量显著降低(P<0.05),IRS-1和IRS-2酪氨酸磷酸化水平均显著降低(P<0.05,P<0.05);(2)不同浓度罗格列酮作用后,PCOS组黄素化颗粒细胞IRS-1mRNA及蛋白表达显著降低,IRS-2mRNA及蛋白表达显著增加,同时IRS-1和IRS-2酪氨酸磷酸化水平也显著增加,而正常对照组黄素化颗粒细胞IRS表达及酪氨酸磷酸化水平无显著变化。结论:PCOS患者卵巢局部存在胰岛素抵抗,其原因可能与IRS-1和IRS-2蛋白表达及酪氨酸磷酸化异常有关;罗格列酮可以通过调整IRS-1和IRS-2表达失衡,提高IRS-1和IRS-2酪氨酸磷酸化水平,改善PCOS患者卵巢局部胰岛素抵抗。

AIM： To explore the effect of rosiglitazone on ovarian insulin resistance in polycystic ovarian syndrome （PCOS） by determining the tyrosine phosphorylation and protein expression of insulin receptor substrate 1 and 2 （IRS - 1, IRS -2） in ovarian luteinizing granulosa cells from patients with PCOS. METHODS： Cultured luteinizing granulosa cells from PCOS （ n = 11 ） and normal ovulatory （ as control, n =15） were obtained in the process of IVF. By treating with different concentrations of insulin for 48 h, the mRNA expressions of insulin receptor substrates （IRS - 1, IRS- 2） in ovarian luteinizing granulose cells were assessed by semi - quantitative RT - PCR. The protein and phosphorylation expressions of insulin receptor substrates （ IRS - 1, IRS - 2 ） in ovarian luteinizing granulose cells were analyzed by Western blot- ting and immunoprecipitation. RESULTS： （1） As compared with control group, luteinizing granulose cells in PCOS patients had higher IRS - 1 mRNA expression and protein content （P 〈 0. 05 ）, but lower IRS -2 mRNA expression and protein content （ P 〈 0. 05 ）. The phosphorylation expressions of IRS - 1 and IRS - 2 were significantly lower （ P 〈 0. 05 ） at the basic state. （2） Rosiglitazone corrected the abnormal protein expression and improved the tyrosine phosphorylation of insulin receptor substrate 1 and 2 （ IRS - 1, IRS - 2） in ovarian luteinizing granulosa cells from patients with PCOS. （3） Rosiglitazone had no effect on the tyrosine phosphorylation and protein expression of insulin receptor substrate 1 and 2 （ IRS - 1, IRS -2） in ovarian luteinizing granulosa cells from normal ovulatory control. CONCLUSION： （1） There is a selective insulin resistance in ovarian luteinizing granulosa cells from patients with PCOS, the reason may be related to abnormal tyrosine phosphorylation and protein expression of insulin receptor substrates. （2） Rosiglitazone improves ovarian function of PCOS, the reason may be related to correct the abnormal protein expression and improve the tyrosine phosphorylation of insulin receptor substrates in ovarian luteinizing granulosa cells.