SHH信号通路在血小板源性生长因子诱导的血管平滑肌细胞增殖中的作用

The role of SHH pathway in PDGF-induced VSMC proliferation

目的探讨sonic hedgehog（SHH）信号通路在血小板源性生长因子（PDGF）诱导的血管平滑肌细胞（VSMC）增殖中的作用。方法体外培养人大隐静脉VSMC，施加PDGF刺激后应用激光共聚焦显微成像及蛋白印迹（Western blot）检测SHH信号通路分子mRNA的表达变化；分别应用慢病毒介导的RNAi技术及SHH信号通路特异抑制剂cyclopamine阻断SHH通路后，用BrdU掺入法联合Ki-67染色评价细胞增殖情况。结果激光共聚焦显微成像发现与对照组相比，PDGF刺激能够显著诱导VSMC中SHH信号通路蛋白shh，Patehedl及Gli2的表达；同时，蛋白印迹也显示PDGF刺激能够明显增加SHH信号通路分子的表达；Gli2-siRNA慢病毒载体能够抑制Gli2的表达，Gli2-siRNA组BrdU掺入量为对照组的（49±0．6）％；与对照组相比，Gli2．siRNA组Ki-67阳性细胞数也明显减少；蛋白印迹显示SHH信号通路特异抑制剂cyclopamine能够抑制SHH信号通路下游转录因子Gli2的表达；cyclopamine组Brdu掺入量为对照组的（52±0．3）％，与对照组相比，cyclopamine组Ki-67阳性细胞数明显减少。结论SHH信号通路在PDGF诱导的VSMC增殖中有重要作用。

Objective To discuss the role of sonic hedgehog （SHH） pathway in PDGF-induced vascular smooth muscle cell proliferation. Method Human vein VSMC were cuhued in vitro. Laser confocal microscopy and Western blot were used to detect the expression of SHH pathway related proteins. The cell proliferation was evaluated by Ki-67 staining and BrdU incorporation after treatment by siRNA of Gli2 or shh pathway inhibitor cyclopamine. Results The results of laser confocal microscopy and Western blot showed that SHH pathway protein which including shh, Patchedl and Gli2 were activated in the PDGF-induced VSMC proliferation. BrdU incorporation assay and Ki-67 stianing showed that the cell proliferation which induced by PDGF was inhibited by Gli2-siRNA and cyclopamine which can both block SHH pathway. Conclusion SHH pathway play an important role in PDGF-induced VSMC proliferation.