内毒素对大鼠原代肝星状细胞ERK1/2信号转导通路的影响

目的研究内毒素对大鼠原代肝星状细胞(hepatic stellate cells,HSCs)增殖活化过程中ERK1/2信号转导通路的影响及机制。方法用链霉蛋白酶、Ⅳ型胶原酶以及密度梯度离心法分离培养大鼠原代HSCs,随机分为对照组、内毒素组和PDTC(Pyrrolidinedithiocarbamic acid,NF-κB抑制剂)组。在培养至第5d时,内毒素组和PDTC组加入终浓度为lμg/ml的内毒素刺激细胞,PDTC组同时加入终浓度为15μmol/L的PDTC,30min后收集各孔HSCs,提取细胞总蛋白,Western Blot检测P-ERK1/2水平。结果内毒素刺激原代培养HSCs后,与对照组相比P-ERK1/2水平明显上升(P<0.01),NF-κB抑制剂PDTC能显著降低该变化。结论内毒素可直接刺激大鼠原代HSCs引起胞内ERK1/2信号传导通路活化,NF-κB信号通路可能是内毒素刺激的原代HSCs所导致ERK1/2信号转导通路活化的重要途径之一。

Effect of endotoxin on ERK1/2 pathway of rat primary HSCs in vitro

Objective To investigate the influence of endotoxin on ERK1/2 pathway of rat primary HSCs in vitro.Methods HSCs were isolated from rats liver by the method of enzymatic digestion and density gradient centrifugation,and randomized into endotoxin group,PDTC(Pyrrolidinedithiocarbamic acid,inhibitor of NF-κB) group and control group.After 5 days normal cultivation,endotoxin and PDTC groups add endotoxin(lμg/ml),PDTC group add PDTC(15μmol/L) as well,the levels of P-ERK1/2 were measured by western blot after incubation for 30 minutes.Results The level of P-ERK1/2 increased significantly after HSCs were stimulated directly by endotoxin,compared with the control group(P <0.01),incubated with PDTC can partly prevent this change(P <0.05).Conclusions Endotoxin can directly stimulate ERK signaling pathway of HSCs,and NF-κB signaling pathway may play an important role in this process.