目的 探讨P38 MAPK通路在缺血再灌注诱导小鼠肝细胞释放高迁移率族蛋白B1(HMGB1)中的作用及其可能机制.方法 建立小鼠肝缺血再灌注损伤模型,分为假手术组(Sham)、缺血再灌注组(IR)与HMGB1释放抑制剂组(GA).检测各组小鼠血清ALT、TNF-α和HMGB1变化,HE染色观察肝组织病理学改变,TUNEL法检测肝脏细胞凋亡情况,免疫组化与Western blot法检测HMGB1、p-P38、P38和Caspase-3的表达.结果 与Sham组相比,在IR组可见ALT(423.4 ±99.6)、TNF-α(84.3 ±21.4)和HMGB1 (0.79 ±0.04)表达增高,而GA组则较IR组降低(P＜0.05).病理学检查可见IR组肝细胞肿胀、肝窦变窄和灶状坏死等变化,而GA组肝组织病理改变较IR组明显改善.与Sham和GA组相比,IR组HMGB1从细胞核向核外释放增加,并且IR组的细胞凋亡率[(59.3±9.1)％]、肝组织HMGB1、p-P38和Caspase-3的表达水平最高(P＜0.05).结论 缺血再灌注诱导小鼠肝细胞释放HMGB1导致肝细胞损伤的机制可能与通过释放HMGB1而激活P38 MAPK通路有关.%Objective To explore the effect of HMGB1 release on P38 MAPK signaling pathway induced by ischemia-reperfusion (IR) in mouse liver.Methods C57BL/6 mice included sham operation group (Sham),IR group (IR) and HMGB1 release inhibitor group (GA).The serum AST,TNF-α and HMGB1 level of the mice were determined using a commercial assay kit.Histopathological changes were observed in mice livers by HE staining.HMGB1,p-P38,P38 and Caspase-3 expression were detected by immunohistochemistry and Western blot,while cell apoptosis was detected by TUNEL assay.Results Compared with Sham group,serum ALT (423.4 ± 99.6),TNF-α (84.3 ± 21.4) and HMGB1 (0.79 ± 0.04)levels were increased in IR group,but decreased in GA group (P ＜ 0.05).The histological changes in the livers of the IR group included hepatocyte swelling,hepatic sinusoids narrowing and hepatocyte necrosis,which were alleviated in GA group.Compared with Sham and GA groups,there was a significant increase on HMGB1 transposition and release,and cell apoptosis [(59.3 ± 9.1)％] in IR group (P ＜ O.05),but GA decreased the HMGB1 level in hepatocyte.The expression of HMGB1,p-P38 and Caspase-3 were up-regulated in IR group compared with those in Sham and GA groups (P ＜ 0.05).Conclusion The release of HMGB1 induced by IR can cause hepatic cell damage probably by stimulating P38 MAPK signaling pathway.
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