环氧合酶-2在高糖刺激的系膜细胞和糖尿病肾病模型大鼠肾皮质的表达及意义

目的探讨环氧合酶-2(COX-2)与糖尿病肾脏病变的关系及在糖尿病肾病发病中的意义。方法Westernblot检测了STZ诱导的糖尿病肾病模型大鼠(DN模型组)肾皮质COX-2的表达,以正常大鼠(对照组)肾皮质做对照;并检测了高糖(HG组)及前列腺素E2(PGE2组)刺激的大鼠肾小球系膜细胞COX-2表达,同时还检测了HG组和PGE2组分别刺激及共同刺激(HG PGE2组)后肾小球系膜细胞的总蛋白量,以正常培养的大鼠肾小球系膜细胞(NG组)作为对照。结果HG组COX-2蛋白表达较NG组明显增加(P<0.01);PGE2也可诱导COX-2的表达增加(P<0.01)。STZ组大鼠肾脏COX-2表达均较CTR组增加(P<0.01);HG组和PGE2组细胞内总蛋白量均较NG组增高(P<0.05),HG PGE2组细胞内总蛋白量较NG组明显增加(P<0.01),HG PGE2组与单纯PGE2刺激组比较也增加(P<0.05)。结论COX-2在高糖和PGE2刺激的肾小球系膜细胞及糖尿病肾病大鼠肾皮质的表达增加,高糖和PGE2可导致肾小球系膜细胞肥大,COX-2可能是导致糖尿病早期肾脏肥大的主要因素之一。

Expressions of COX-2 in mesangial cells stimulated by high glucose and renal cortex in rats with diabetic nephropathy and its significance

Objective To explore the significance of relationship between COX-2 and diabetic nephropathy (DN) and its role in the onset of DN.Methods The expressions of COX-2 protein in renal cortex of diabetes rats induced by STZ were detected by Western blot, renal cortex of normal rats as control. The expression of COX-2 protein in mesangial cells induced by high glucose (HG) or COX-2 major metabolite PGE_2 were deteted by Western blot. Furthermore, the total protein content in mesangial cells induced by HG, PGE_2,HG PGE_2 stimulation was mesasured.Results COX-2 protein expression was markedly increased in HG group and PGE_2 group compared with that of controls(P<0.01). The kidney hypertrophy index and COX-2 expression in the cortical tissue were significantly increased in STZ group compared with those in control group(P<0.01). The total protein content was significantly increased in HG and PGE_2 group compared with that in control group(P<0.05). The total protein content was significantly increased in HG PGE_2 group compared with that in control and PGE_2 group(P<0.05).Conclusions COX-2 expression is increased in mesangial cells stimulated by HG and renal cortex in DN rats. COX-2 might be one of important factors related to the pathogenesis of renal hypertrophy in eraly DN.