PPAR-γ在多囊卵巢综合征大鼠卵巢组织中的表达及意义

摘要

目的:探讨过氧化物酶增殖物激活受体-γ(PPAR-γ)在多囊卵巢综合征(PCOS)大鼠卵巢的表达与其性激素变化及胰岛素抵抗(IR)的关系.方法:应用脱氢表雄酮(DHEA)皮下注射23日龄SD雌性大鼠20 d,观察卵巢巢重量及光镜(HE染色)形态学改变,应用ELISA(酶联免疫法)测定T、E2、LH、FSH及血清胰岛素、糖耐量试验,应用荧光定时定量聚合酶链反应(real-time PCR)检测PPAR-γmRNA的表达.结果:实验组卵巢重量显著高于对照组(P<0.05),实验组卵巢呈多囊样改变而黄体形体比例减少;实验组血清T、E2、FSH、空腹血糖水平显著高于对照组(P<0.05),空腹胰岛素及胰岛素抵抗指数(HOMA-IR)显著高于对照(P<0.05);在PCOS大鼠卵巢中PPAR-γ相对含量显著高于对照组(P<0.05).结论:DHEA诱导的PCOS大鼠动物模型与PCOS患者相似,PPAR-γ在PCOS大鼠卵巢发育中起部分调节作用,并与PCOS的IR密切相关.%Objective To study the expression of peroxisome proliferator-activated receptor-y (PPAR-"y) in the ovary tissue of poly cystic ovary syndrome (PC OS) rat and hormonal changes and insulin resistance (IR). Methods Rat model induced by subcutaneous injecting dehydroeplandrosterone (DHEA) and 23-day-old female SD rats were divided into two groups in pairs. Rats in group 1 were injected daily with DHEA for up to 20 days and rats in group 2 injected with oil at the same time. Ovarian weight, serum insulin levels and sex hormone levels in rat blood of both groups were determined with ELISA method. Oral glucose tolerance tests, light microscopic examination were performed. Levels of PPAR-"y mRNA in ovary tissue were measured with time fluorescence quantitative polymerase chain reaction (real-time PCR) method. Results The ovarian weight in group 1 was higher than that in group 2 (P < 0.05). The ovaries in group 1 showed multiple follicular cysts, and the ratio of follicular cysts to normal follicle was significantly increased, while the ratio of corpus luteum was decreased. The serum levels of testosterone and estradiol 2 and follicle-stimulating hormone, fasting serum glucose were significantly higher in group 1 than those in group 2(P < 0.05), fasting serum insulin and Insulin resistant index(HOMA-IR) (P < 0.05). In addition, the PPAR-"y mRNA level of the ovary tissue of DHEA-induced group was significantly higher than that in the control rats (P < 0.05). Conclusion The DHEA-induced rat PCOS model was similar to the patient with PCOS. PPAR-"y plays the part of regulatory role on ovarian development of the PCOS rat. PPAR-"y is closely related with insulin resistant of poly cystic ovary syndrome (PCOS).