衣霉素对高糖刺激肾系膜细胞增殖的影响及其机制研究

Effects of turicamycin on proliferation of high glucose-induced glomerular mesangial cells and its mechanism study

目的观察N-糖链抑制剂衣霉素(TM)对肾小球系膜细胞(GMC)β1整合素以及其下游重要信号分子粘着斑激酶(FAK)和细胞周期正调控蛋白cyclinD1表达的影响。了解衣霉素在抑制高糖刺激GMC增殖中的重要作用。方法体外培养的大鼠系膜细胞株分为:正常对照组,高糖组,甘露醇组,高糖加不同浓度衣霉素(TM)组。用流式细胞技术检测β1整合素的表达;免疫组化方法测定FAK和细胞周期素D1(cyclinD1)的表达,四唑盐比色(MTT)法测定细胞增殖。结果正常系膜细胞中β1整合素、FAK和cyclinD1均有一定表达,高糖作用24h可以使3者表达明显升高,细胞增殖能力增强,且与渗透压无关。衣霉素(TM)可呈浓度依赖性的抑制高糖的这种作用。结论N-糖链抑制剂TM通过阻断细胞表面糖蛋白的糖基化过程,形成脱糖蛋白,从而抑制β1整合素的表达,并进一步影响细胞FAK和cyclinD1表达,使高糖诱导的细胞增殖受抑制。

Objective To observe the effects of turicamycin-inhibitor of N-glycosylation of proteins on expression of (β1 integrin,FAK and cyclin D1 in high glucose-induced glomerular mesangial cells (CMC), and to explore the mechanism concerned. Methods Cultured HBZY-1 rat mesangial cells were divided into 5 groups:control group;high glucose group;mannitol group;high glucose plus TM group; TM group.The expression of β1 integrin was measured by flow cytometry, expression of FAK and cyclin D1 was measured by immunohistochemistry,and proliferation of GMCs was measured by MTT. Results There was a little expression of β1 integrin, FAK and cyclin D1 on normal mesangial cells. High glucose induced the proliferation and increased the expression of β1 integrin and cyclin D1.There was no significant difference in mannitol group as compared to control group.The expression of (β1 integrin FAK and cyclin D1 decreased notably by TM.TM could also decrease proliferative abilitiy of cells. All the effects of TM were dose-dependent. Conclusion Through blocking glycosylation of glycoprotein, TM can suppress cellular proliferation and expression of pi integrin induced by high glucose in a dose-dependent manners,then pi integrin affects the expression of FAK and cyclin D1.