p-JNK蛋白在妊娠期糖尿病孕鼠子宫组织中的表达及其意义

目的:探讨磷酸化c-jun氨基末端激酶(p-JNK)蛋白在妊娠期糖尿病孕鼠子宫组织中的表达情况,及其在GDM发病机制中的作用。方法:用免疫组化和Western-blotting法检测妊娠期糖尿病大鼠(GDM组,n=10只)、给予JNK抑制剂SP600125(SP组,n=10只)和正常妊娠大鼠(正常妊娠组,n=10只)子宫组织中p-JNK的表达,同时检测空腹血糖水平(FPG)、空腹胰岛素水平(FINS)和胰岛素抵抗指数(HOMA-IR)。结果:①GDM组孕鼠FPG、FINS及HOMA-IR水平均明显高于正常妊娠组(P<0.05)。②p-JNK主要在子宫腺上皮、间质细胞和少量平滑肌细胞的胞浆和胞核中表达,GDM组子宫组织中p-JNK的表达水平明显高于正常妊娠组,差异有统计学意义(P<0.05)。JNK抑制剂SP600125干预后GDM孕鼠子宫组织中p-JNK表达显著减少(P<0.05)。③GDM组子宫组织中p-JNK蛋白表达水平与HOMA-IR呈正相关(r=0.763,P<0.05);SP组及正常妊娠组则均无相关性(r=0.549、0.482,P<0.05)。结论:JNK蛋白的活化与GDM胰岛素抵抗密切相关,p-JNK表达异常可能在GDM发病机制中发挥着重要的作用。

Expression and significance of p-JNK protein in uterine tissues of pregnant rats with gestational diabetes mellitus

Objective:To explore the expression of p-JNK protein in uterine tissues of pregnant rats with gestational diabetes mellitus(GDM) and its effect in pathogenesis of GDM.Methods:The expression levels of p-JNK protein in uterine tissues from 10 pregnant rats with GDM(GDM group),10 pregnant rats with GDM treated with JNK inhibitor SP600125(SP group,n=10) and normal pregnant rats(normal pregnancy group,n=10) were detected by immunohistochemical method and Western blotting,at the same time,the levels of fasting plasma glucose(FPG),fasting insulin(FINS) and insulin resistance index(HOMA-IR) were measured.Results:The levels of FPG,FINS and HOMA-IR in GDM group were significantly higher than those in normal pregnancy group(P<0.05).p-JNK localized in glandular epithelium,stromal cells,cytoplasm and nucleus of a few smooth muscle cells;the expression level of p-JNK protein in uterine tissues of GDM group was significantly higher than that of normal pregnancy group(P<0.05).After administration of SP600125,the expression level of p-JNK protein in uterine tissues of GDM group decreased significantly(P<0.05);in GDM group,there was a positive correlation between expression level of p-JNK protein and HOMA-IR(γ=0.763,P<0.05),but there was no correlation in SP group and normal pregnancy group(γ=0.549,0.482,P>0.05).Conclusion:The activation of JNK protein is closely related to insulin resistance,the abnormal expression of p-JNK protein in uterine tissues may play an important role in pathogenesis of GDM.