库普弗细胞Toll样受体2在小鼠肝脏缺血再灌注损伤中的表达及意义

目的探索库普弗细胞Toll样受体2(TLR2)在肝脏缺血再灌注损伤中的表达变化,分析库普弗细胞TLR2信号通路参与肝脏缺血再灌注损伤的机制。方法动物分假手术对照(SH)组、缺血再灌注(I/R)组及氯化钆处理(Gd)组,复制小鼠肝脏部分缺血1 h再灌注4 h损伤模型,结束再灌注后,取缺血叶肝脏组织及其库普弗细胞,提取总RNA及膜蛋白质分析TLR 2 mRNA及蛋白的表达,同时提取缺血肝叶组织核蛋白分析核因子(NF—κB),并检测门静脉血中肿瘤坏死因子(TNF α)、丙氨酸氨基转移酶(ALT) 及内毒素水平。结果再灌注4 h,(1)I/R组缺血肝叶TLR2 mRNA及蛋白表达水平较SH组高,△Ct值分别为1.06±0.91和5.08±1.32,t=7.80,P<0.01;A值分别为433.91±25.53和102.86±13.58,t=28.04, P<0.01。Gd组缺血肝叶TLR2 mRNA及蛋白表达水平较I/R组下降,△Ct值分别为4.22±0.84和1.06±0.91,t=7.56,P<0.01;A值分别为125.89±15.49和433.91±25.53,t=25.27,P<0.01。(2)I/R组缺血肝叶库普弗细胞中TLR2 mRNA及蛋白表达水平较SH组高,△Ct值分别为0.52±0.23和2.61±0.1 8, t=17.47,P<0.01;A值分别为379.70±34.16和114.98±21.90,t=15.98,P<0.01。Gd组缺血肝叶库普弗细胞中TLR2 mRNA及蛋白表达水平则较I/R组下降,△Ct值分别为1.90±0.14和0.52±0.23,t= 12.

Activation of Kupffer cell TLR2 signaling pathway during hepatic ischemia/reperfusion injury process in mice and it's significance

OBJECTIVE: To study changes of TLR2 signaling pathway expression in Kupffer cells during the process of hepatic ischemia/reperfusion in a mice model and the mechanism of TLR2 signaling pathway participating in hepatic ischemia/reperfusion injury. METHODS: BALB/c mice were divided into 3 groups: sham operation (SH), ischemia/reperfusion (I/R) and GdCl3 treatment (Gd) groups. After 4 h of reperfusion, the expression of TLR2 mRNA and membrane TLR2 protein were analyzed in ischemic lobes of the livers, and in Kupffer cells isolated from ischemic lobes. The expression of NF-kappaB in ischemic lobes was also examined. Levels of endotoxin, ALT and TNFalpha were measured at the same time point. RESULTS: The expressions of TLR2 mRNA and protein in both ischemic hepatic lobes and Kupffer cells isolated from ischemic lobes were increased in the I/R group compared to those in the SH group, as well as the expression of NF-kappaB in ischemic lobes, which was down regulated by intravenous GdCl3 treatment. Levels of ALT and TNFalpha in the portal vein were higher in the I/R group than in the SH group, which also were decreased with treatment of GdCl3. The level of endotoxin in the three groups remained constant. CONCLUSION: TLR2 signaling pathway in Kupffer cells is activated during the process of hepatic ischemic/reperfusion injury. The activation of TLR2 signaling pathway in Kupffer cells may play a role in this process.