糖尿病大鼠肾小管间质缺氧诱导因子2α表达变化及氯化钴对其影响

Changes of Hypoxia-Inducible Factor 2α Expression and Effect of Cobalt Chloride on Renal Tubulointerstitial in Diabetic Rats

目的:观察缺氧诱导因子2α(HIF-2α)在2型糖尿病(T2DM)大鼠肾小管间质的表达及其降解抑制剂氯化钴(CoCl_2)的干预作用。方法:24只健康Wistar大鼠,留取8只作为对照(CON组),余16只采用链脲佐菌素(STZ)腹腔注射构建T2DM模型,成模后平分为T2DM组(DM组)和CoCl_2干预组(DM+CoCl_2组)。24周后取大鼠肾脏,常规方法制作石蜡切片。采用免疫组化法检测大鼠肾组织HIF-2α表达水平;PAS染色法检测大鼠肾组织结构病理变化及半定量分析肾小球硬化指数(GSI)和小管间质纤维化指数(IF);TUNEL法检测肾小管上皮细胞凋亡率;免疫印迹法检测肾组织促红细胞生成素(EPO)表达水平。结果:DM组和DM+CoCl_2组大鼠肾组织HIF-2α表达高于CON组(P<0.01),DM+CoCl_2组HIF-2α表达水平较DM组更高(P<0.01);DM大鼠肾小球系膜基质及细胞轻度增生,肾小管间质区域增宽、细胞外基质聚集,其GSI和IF均显著高于CON组(P<0.01),与DM组比较,DM+CoCl_2组上述病理改变减轻,GSI和IF降低(P<0.01)。DM组肾小管上皮细胞凋亡率高于CON组(P<0.01),而DM+CoCl_2组细胞凋亡率较DM组降低(P<0.01)。DM组肾组织EPO表达水平低于CON组(P<0.05),而DM+CoCl_2组EPO水平高于DM组(P<0.05)。结论:上调肾组织HIF-2α表达可减轻T2DM大鼠肾间质损害。

Objective:To observe the expression of hypoxia-inducible factor 2α(HIF-2α)and the intervention effect of cobalt chloride(CoCl2)in renal tubulointerstitial of diabetic rats.Method:STZ was injected into the rats by intraperitoneal injection.24 rats were divided into three groups:Control(CON)group(n=8),DM group(n=8),DM+CoCl2 group(n=8).After 24 weeks the expression of HIF-2α in the kidneys was detected by immunohistochemistry.PAS staining,GSI and IF semi-quantitative analysis were used to evaluated renal pathological changes.Renal tubular epithelial cell apoptosis was detected by TUNEL staining.Western blotting was used to detect the expression of EPO.Results:Immunohistochemistry result showed the expression of HIF-2 αin DM group was higher than that in CON group(P<0.05),but lower than that in DM+CoCl2 group(P<0.01).PAS staining showed that the proliferation of glomerular mesangial matrix and cells in DM rat,and GSI and IF were significantly increased in DM group,which were higher than those in DM+CoCl2 group(P<0.05).TUNEL staining showed that the apoptosis of glomerular tubular epithelial cells in DM group was increased and higher than that in DM+CoCl2 group(P<0.01).The expression of EPO in DM group were lower than that in CON group and DM+CoCl2 group(P<0.05).Conclusion:CoCl2 can increase the expression of HIF-2α,which may be related to the reduction of renal interstitial injury in diabetic rats.