P38MAPK在脂多糖引起的腹膜间皮细胞损伤中的作用

The role of P38MAPK in LPS-induced peritoneal mesothelial cells injury

目的探讨脂多糖(LPS)引起人腹膜间皮细胞(HPMC)损伤中分泌MCP-1以及LPS、P38MAPK、MCP-1三者之间可能存在的关系。方法体外培养永生化人腹膜间皮细胞(HPMC),随机分为正常对照组、LPS作用24 h组、LPS作用48 h组、特异性P38MAPK阻断剂SB203580+LPS作用24 h组、SB203580+LPS作用48 h组;Western blot法检测各组MCP-1和磷酸化P38MAPK蛋白表达水平;Real-time PCR法检测各组MCP-1 mRNA表达水平。结果 1.10 mg/L LPS刺激使HPMC的MCP-1 mRNA和蛋白质表达均较正常对照组增加(P<0.05)。10 mg/L LPS作用48 h后MCP-1 mRNA和蛋白质表达水平均高于24 h组(P<0.05);Western blot结果显示,与正常组对比,10 mg/L LPS作用使磷酸化P38MAPK蛋白水平明显升高(P<0.05)。10 mg/L LPS作用48 h与作用24 h对比升高不明显(P>0.05);经5μmol/L SB203580预处理30 min后再予以LPS刺激与单纯LPS刺激相比较,MCP-1蛋白质和mRNA均明显降低(P<0.05);SB203580预处理后再予以LPS分别刺激24 h和48 h 2组相比较,MCP-1蛋白及mRNA水平差异不明显(P<0.05)。结论 LPS通过磷酸化P38MAPK,导致MCP-1表达水平升高,诱发腹膜间皮细胞的损伤。

This study performed to investigate the role and mechanism of P38MAPK and MCP-1 in LPS-induced injury of cultured human peritoneal mesothelial cells （HPMCs）. Cultured HPMCs were randomly assigned into control group, LPS stimulated for 24 hours group （24 h LPS）, LPS stimulated for 48 hours group （48 h LPS）, specific P38MAPK inhibitor SB203580＋24 h LPS group, and SB203580＋48 h LPS group. The MCP-1 protein expression and phospho-P38MAPK were determined by Western blot, while the MCP-1 mRNA expression was determined by real-time PCR. After LPS stimulation, MCP-1 mRNA and protein expression of HPMCs were increased （P〈 0.05） compared with control group. MCP-1 mRNA and protein expression of IdPMCs stimulated with LPS for 48 hours were higher than those for 24 hours （P〈 0.05）. Western blot showed that, compared with the control group, LPS stimulation increased the phosphorylation of p38MAPK （P 〈 0.05）. The phosphorylation levels of p38MAPK of HPMCs stimulated with LPS for 48 hours has no significant difference compared with those for 24 hours（P〈0.05）. Pretreatment with 5 μmol/L SB203580 for 30 minutes could notably decrease MCP-1 expression in both protein and mRNA levels （P 〈 0.05）. After pretreatment with 5 μmol/L SB203580 for 30 minutes, no significant alteration of MCP-1 mRNA and protein expression were detected between LPS 24-hour group and 48- hour group （P〈0.05）. We conclude that P38MAPK acts as an upstream factor in LPS-induced MCP-1 expression during HPMC injury.