肝大部分切除或HGF刺激可以引起STAT3和TEC的同时激活

Activation of TEC and STAT3 after partial hepatectomy or hepatocytic growth factor stimulation

目的:了解STAT3和TEC在肝再生以及HGF刺激的肝干细胞中激活情况,探讨在肝细胞早期增生中STAT3和TEC 的活化的相关性. 方法:建立小鼠肝大部分切除和HGF刺激肝干细胞(WB F- 344)的体内、体外两个试验模型,采用免疫沉淀(immun- oprecipitation,IP)、免疫印迹(immunoblotting,IB)的方法检测TEC和STAT3酪氨酸磷酸化激活水平与时间, 使用凝胶阻滞实验(electrophoretic mobility shin assay, EMSA)分析核蛋白与STAT3 DNA特异序列的结合能力. 结果:肝大部分切除和HGF刺激下STAT3和TEC的磷酸化水平均快速明显升高,肝大部分切除后10-20 min时二者激活水平均达到最高,HGF刺激后10 minTEC激活水平最高,30 min STAT3活化水平最高.肝大部分切除或HGF 刺激下10 min左右,核蛋白与STAT3 DNA特异序列的结合能力明显增强. 结论:肝大部分切除和HGF刺激下STAT3和TEC均被快速激活,他们之间可能存在相互作用,共同影响肝细胞早期增生反应.

AIM: To study the activation of TEC and STAT3 in the hepa-tocyte after partial hepatectomy (PH) or hepatocytic growth factor (HGF) stimulation in the mice. METHODS: Mice of SPF degree and WB F-344 cell (liver stem cell line) were used in this study. In vivo and in vitro experimental models of PH and HGF stimulation were established respectively. Immunoprecipitation (IP) and immunoblotting (IB) were used to observe the phosphory-lation level and time of TEC and STAT3. On the other hand, electrophoretic mobility shift assay (EMSA) was used to detect the binding ability of STAT3 DNA. RESULTS: TEC and STAT3 were both inducibly phosphory-lated in one hour after PH or HGF stimulation. Ten to twenty minutes after PH, levels of TEC and STAT3 reached the peak. About 10 min after HGF stimulation, TEC phospho-rylation level reached maximum value and about 30 min STAT3 phosphorylation level reached peak value. Meanwhile, STAT3 DMA binding activity was enhanced both in vivo and in vitro experiments. CONCLUSION: After PH or HGF-stimulation, both TEC and STAT3 are quickly phosphorylated in one hour, and they synergically affect the early proliferation of hepatocytes.