高糖对肾小球系膜细胞ERK1／2蛋白表达泛素化调节的影响

目的探训高糖作用的肾小球系膜细胞ERK1／2蛋白表达与泛素一蛋白酶体调节途径的关系。方法体外培养大鼠肾小球系膜细胞，将高糖作为刺激因子，特异性泛素蛋白酶体抑制剂MG132作为干预闪素。脂蛋白免疫印迹法检测各组系膜细胞ERK1／2的表达，细胞免疫荧光染色及激光共聚焦娃微镜检测各组系膜细胞ERK1/2的表达、转位。结果高糖组系膜细胞ERK1/2表达较正常血糖组均增多（P〈0．05），还可促进ERK1/2由胞浆向胞核内激活、转位，高糖组加入MG132后，系膜细胞ERKl／2表达和激活、转位均减弱（P〈0．05）。结论高糖可通过泛素蛋白酶体途径诱导肾系膜细胞ERK1／2表达增强和ERK1／2由胞浆向胞核内激活、转位。

The effect of high glucose on the expression of ERK1/2 in glomerular mesangial cells via ubiquitin-proteasome pathway

Objective To explore the relationship betweea ubiquitin-proteasome pathway（UPP） and ERK1/2 in cultured rat glomerular mesangial cells. Methods The cultured HBZY-1 ratglomerular mesangial cells were stimulated by high glucose, MG132 as an inhibitor of UPP was used to act on the cells. The expression of ERK1/2 were measured by Western-blotting assay, and the activation of ERK1/2 were measured by immunofluorescence and laser scanning confocal microscope. Results Compared with normal glucose group, the values of ERK1/2 expression, activation and transposition from endochylema to nucleus were increased in high glucose groups. The expression of ERK1/2 in high glucose groups were decreased obviously after adding MG132 （P〈0.05）. Conclusions High glucose can significantly increase the expression of ERK1/2 via the UPP and its activation and transposition from endoehylema to nucleus.