p38MAPK介导PDGF-BB诱导的大鼠血管平滑肌细胞MMP-2基因表达

p38MAPK Mediates PDGF-BB-induced MMP-2 Expression in Rat Vascular Smooth Muscle Cells

目的观察血小板源性生长因子BB(PDGF-BB)是否可以诱导大鼠血管平滑肌细胞(VSMC)基质金属蛋白酶2(MMP-2)基因表达及VSMC的迁移,探讨p38信号通路在这一过程中的作用,为血管重建性疾病的研究提供实验依据。方法 PDGF-BB不同浓度和不同时间刺激体外培养的大鼠VSMC,用放线菌素D、SB202190(MAPK/p38特异性抑制剂)处理PDGF-BB诱导的VSMC。细胞划痕实验检测细胞迁移,运用Real-time RT-PCR检测MMP-2基因表达水平,Western blot检测p38的活性变化。结果 PDGF-BB可促进VSMC迁移,SB202190可抑制PDGF-BB诱导的VSMC迁移。不同浓度PDGF-BB(10μg/L^50μg/L)作用VSMC 0.5 h,MMP-2基因表达明显增加,其中以20μg/L较显著;用20μg/L PDGF-BB作用VSMC 0.5 h^4 h,可显著上调MMP-2基因表达,以0.5 h较显著。用放线菌素D和SB202190预处理后MMP-2基因表达降低。PDGF-BB可激活VSMC中磷酸化p38水平,SB202190可抑制p38的磷酸化以及相应的MMP-2基因表达。结论 p38参与了PDGF-BB诱导的VSMC迁移及MMP-2基因表达。

Aim To study the expression of matrix metalloproteinase-2（ MMP-2） gene in vascular smooth muscle cells（ VSMC） induced by platelet-derived growth factor BB（ PDGF-BB） and the dependent signaling pathway. Methods VSMC isolated from rats were treated with PDGF-BB at different concentration and durations. The expression of MMP-2 mRNA was detected by Real-time RT-PCR. The p38 activity was detected by Western blot. Actinomycin D,SB202190 were used to investigate underlying mechanisms. Cell migration was tested by scratch. Results MMP-2 mRNA expression was up-regulated by PDGF-BB for 1 h at 10 μg / L ~ 50 μg / L,and maximally induced at 20 μg / L. The time of MMP-2 mRNA expression maximally occurred 30 min after PDGF-BB exposure. Incubation of VSMC with PDGF-BB resulted in a significant activation of p38. VSMC pretreated with actinomycin D showed a significant decrease of MMP-2 mRNA expression. SB202190 resulted in inactivation of p38,meanwhile,significantly suppressed of MMP-2 mRNA expression on PDGFBB treatment. Conclusion PDGF-BB can induce expression of MMP-2 gene and cell migration in VSMC,which can be regulated by p38 signaling pathway. This process may play a critical role in development of vascular remodeling.