血小板来源的生长因子通过ERK/p38/PI3K促进人视网膜色素上皮细胞的增殖、迁移

目的:探讨血小板来源的生长因子(PDGF)对体外培养的人视网膜色素上皮细胞(RPE)增殖和迁移的影响,并对参与其中的信号通路做初步研究.方法:体外培养的人视网膜色素上皮细胞与含有重组人血小板来源的生长因子的培养基(含有或不含2％(v/v)胎牛血清)共培养,用MTT法检测PDGF对RPE细胞增殖的影响,利用细胞爬片和免疫荧光技术检测PDGF对RPE细胞迁移等影响；另外分别向细胞培养物中添加PD98059,SB203580和PI3K等不同的信号通路分子抑制剂,判断参与PDGF激活的细胞活动相关的信号通路.结果:外源性PDGF能促进体外培养的人RPE的增殖和迁移.ERK1/2选择性抑制剂PD98059和PI3K抑制剂LY294002能显著的降低PDGF-BB诱导的人RPE细胞的增殖(P＜0.05),p38抑制剂SB203580没有明显的抑制作用.而对PDGF-BB诱导的RPE细胞的迁移,SB203580和LY294002有显著的抑制作用(P＜0.05),PD98059抑制作用不显著.结论:PDGF对RPE细胞的影响提示其在增生性玻璃体视网膜病变(PVR)的发展中有重要的作用,其可能为PVR提供一种新的毒副作用小的治疗手段.

Platelet-derived Growth Factor Induces Human Retinal Pigment Epithelial Cells Proliferation and Migration Through ERK/p38/PI3K

Objective： To investigate the pro-proliferation and pro-migration effects of platelet-derived growth factor（PDGF） on cultured human retinal pigment epithelial cells（RPE）,and the signaling pathways involved in PDGF induced cell activation.Methods： Human RPE cells were co-cultured with DMEM or 2% DMEM （containing 2%（v/v） fetal bovine serum（FBS）] with or without recombined human PDGF-BB,and cell viability and migration were detected by MTT methods and cell climbing slice,respectively.In addition,different signaling inhibitors,PD98059,SB203580 and PI3K,were added to cell cultures to determine the pathways responsible for PDGF-induced cell activation.Results： PDGF-BB could induce the proliferation and migration of human RPE cell.PD98059,the selective inhibitor of ERK1/2 activation,and LY294002,the PI3K blocker,decreased the rate of cell proliferation at un-stimulated control conditions while SB203580,the selective inhibitor of p38 activation,had no effect on the control proliferation rate.The addition of LY294002 and SB203580 largely inhibited exogenously applied PDGF induced human RPE cell migration while PD98059 had little inhibition.Conclusion： The promotion of PDGF on cultured human RPE cells suggested that PDGF plays vital role in the process of proliferative vitreoretinopathy（PVR）,and further research aimed at the exact role of PDGF in PVR may provide a new treatment for PVR with less toxicity.