白杨素抑制血小板源性生长因子诱导的血管平滑肌细胞迁移和表型转换

Effects of Chrysin on Platelet Derived Growth Factor- induced Migration and Phenotypic Switching of Vascular Smooth Muscle Cells

目的研究白杨素对血小板源性生长因子(PDGF)-BB诱导的血管平滑肌细胞(VSMCs)迁移和表型转换的影响及可能的分子机制。方法采用Transwell小室法评价白杨素对PDGF-BB诱导的VSMCs迁移的影响,Western blot法测定收缩型VSMCs标志蛋白:α-平滑肌肌动蛋白(α-SMA)、平滑肌22α(SM22α)和结蛋白的表达水平,以及AKT和糖原合酶激酶(GSK)3β的总蛋白和磷酸化蛋白水平。结果 20ng/ml PDGF-BB明显促进VSMCs迁移,而12.5μmol/L白杨素预处理能显著抑制PDGF-BB诱导的VSMCs迁移;20ng/ml PDGF-BB显著降低VSMCs中α-SMA、SM22α和结蛋白的蛋白表达水平,而12.5μmol/L白杨素预处理能逆转这些标志蛋白的下调;20ng/ml PDGF-BB显著升高VSMCs中AKT和GSK3β磷酸化表达水平,12.5μmol/L白杨素预处理几乎完全阻断PDGF-BB诱导的这些信号分子的磷酸化。结论白杨素显著抑制PDGF-BB诱导的VSMCs迁移,并能阻止PDGF-BB诱导的VSMCs收缩表型向合成表型转换,其机制可能部分与抑制AKT信号通路活化有关。

Objective To investigate the effects of ehrysin on the migration and phenotypie switching of vascular smooth muscle cells （VSMCs） induced by platelet derived growth factor （PDGF） - BB and the possible molecular mechanism. Methods Migration of VSMCs was determined by transwell assay. Western blot was performed using antibodies against the following contractile VSMC markers： α - smooth muscle aetin （ α - SMA） , smooth muscle 22α （SM22α） , and desmin. Western blot was also carried out to evaluate total and phosphorylated protein levels of AKT, and glycogen synthase kinase 3β （GSK3β）. Results Treatment of VSMCs with PDGF - BB （20ng/mL） significantly increased the number of migrated cells. However, 12.5μLmol/L ehrysin pretreatmenl markedly blocked this migration response. The expression levels of α - SMA, SM22α and desmin were significantly reduced in PDGF - BB - stimulated VSMCs. In contrast, 12.5μmol/L ehrysin pretreatment reversed the downregulation of these markers. PDGF -BB induced a significant increase in the levels of phosphorylatcd AKT, and GSK3β. However, the PDGF - BB - induced activation of these signaling molecules was almost completely blocked by 12.5μmol/L ehrysin pretreatment. Conclusion Chrysin can suppress the migration of VSMCs induced by PDGF - BB and prevent the phenotypic switching of VSMCs from a ＂contractile＂ to a ＂synthetic＂ state in response to PDGF - BB. These beneficial effects on VSMCs were at least partly mediated by the inhibition of the AKT signaling pathways.