热休克蛋白90对血小板源衍生因子诱导的大鼠主动脉平滑肌细胞增殖的影响

Effect of Heat Shock Protein 90 on Proliferation of Rat Aortic Smooth Muscle Cells Induced by Platelet Derived Growth Factor

目的:研究热休克蛋白90(HSP90)对血小板衍生因子(Platelet derived growth factor,PDGF)诱导的大鼠主动脉平滑肌细胞增殖的影响。方法:采用胶原酶消化法原代培养大鼠胸主动脉平滑肌细胞,应用脂质体细胞转染siRNA的方法抑制HSP90的表达,定量PCR和western blot的方法检测抑制效率。利用PDGF-bb诱导刺激平滑肌细胞增殖,CCK8法检测细胞增殖能力的变化,流式细胞术检测细胞生长周期的改变。结果:平滑肌细胞中转染HSP90的siRNA后,HSP90的mRNA和蛋白水平明显降低,分别为对照组的65.3%和57.6%(P<0.05);PDGF-bb刺激明显促进平滑肌细胞生长,而降低HSP90水平显著影响PDGF-bb诱导的细胞增殖(P<0.05);流式细胞术检测发现降低HSP90水平引起平滑肌细胞生长停滞,分布在细胞周期G1期的细胞比例明显增多(P<0.05)。结论:HSP90通过调控平滑肌细胞的生长周期参与调节细胞增殖过程。

Objective： To investigate the effect of heat shock protein 90 （HSP90） on proliferation of rat aortic smooth muscle cells induced by PDGF （Platelet derived growth factor）. Methods： The primary aortic smooth muscle cells were cultured from thoracic aortas by collagenase digestion methods. The expression of HSP90 was intervened by liposomes with siRNA, and determined by real-time PCR and western blot. Proliferation of smooth muscle cells were stimulated PDGF-bb, and were detected by CCK8 assay. The cell cycle of smooth muscle cells were determined by flow cytometry. Results： Smooth muscle cells transfected with siRNA 24 h later, mRNA and protein levels of HSP90 significantly decreased by 65.3% and 57.6% respectively, compared with control groups. The proliferation of fibroblasts were markedly promoted by PDGF-bb, but HSP90 siRNA suppressed the cell proliferation. Flow cytometry assay showed that smooth muscle cells transfected with HSP90 siRNA were found arrest in the G1 phase of the cell cycle. Conclusions： HSP90 is involved in the proliferation of smooth muscle cells by regulating cell cycle.