晚期糖基化终产物诱导人近端肾小管上皮细胞纤溶酶原激活物抑制剂-1表达上调并活化NADPH氧化酶

Advanced glycation end products induce expression of PAI-1 in cultured human proximal tubular epithelial cells through NADPH oxidase dependent pathway

目的:研究晚期糖基化终产物(AGES)修饰蛋白诱导人近端肾小管上皮HK-2细胞分泌纤溶酶原激活物抑制剂-1(PAI-1)的影响及其相关的氧化应激传导途径。方法:采用不同浓度AGES修饰的人血清白蛋白(AGES-HSA)与肾小管上皮HK-2细胞共培养。用光泽精化学发光法检测细胞匀浆中NADPH氧化酶活性,ELISA检测细胞上清液中PAI-1蛋白分泌,RT-PCR法检测PAI-1mRNA表达。结果:AGES-HSA诱导HK-2细胞NADPH氧化酶活化,并以时间、剂量依赖方式上调PAI-1蛋白和mRNA的表达。运用NADPH氧化酶抑制剂DPI、apocynin、氧自由基清除剂SOD可以明显阻断AG-ES-HSA诱导的PAI-1表达。结论:AGES-HSA可通过NADPH氧化酶依赖的氧化应激途径上调肾小管上皮细胞PAI-1表达。

AIM： To investigate the effects of advanced glycation end products （AGES） on secretion of plasmino- gen activator inhibitor-1 （ PAI-1 ） by human proximal tubular epithelial cells and its NADPH oxidase dependent pathway. METHODS： Human proximal tubular epithelial cells were cultured in vitro with indicated concentration of AGES modi- fied human serum albumin （AGES-HSA）. NADPH oxidase activity were detected by lucigenin-enhanced chemiluminescence. The production of PAI-1 was evaluated by enzymelinked immunoadsorbent assay （ELISA）. The PAI-1 mRNA expression was assayed by reverse transcription polymerase chain reaction （RT-PCR）, RESULTS： AGES-HSA were associated with enhanced oxidative stress and NADPH oxidase activity. AGES-HSA upregulated the expression of PAI-1 mRNA and protein with dose and time dependent fashion. AGES-HSA-induced PAI-1 expression were significantly suppressed by the NAD（P） H oxidase inhibitors DPI, apocynin or O2- scavenger SOD. CONCLUSION： AGESHSA stimulate tubular epithelial cells to produce PAI-1 through activation of NADPH oxidase.