氧化型低密度脂蛋白对血管平滑肌细胞小凹蛋白1表达的抑制作用及其与信号调节激酶的关系

The Inhibitory Effect of Oxidized Low Density Lipoprotein on the Expression of Caveolin-1 in Vascular Smooth Muscle Cell and Its Relation with Extracellular-signal Regulated Kinases 1/2

目的观察氧化型低密度脂蛋白对血管平滑肌细胞小凹蛋白1表达的抑制作用及其与细胞外信号调节激酶活性的关系。方法50mg/L氧化型低密度脂蛋白处理血管平滑肌细胞不同时间,或同时加入25μmol/L细胞外信号调节激酶信号通路的特异性阻断剂,Western印迹检测血管平滑肌细胞小凹蛋白1和细胞外信号调节激酶的变化。结果50mg/L氧化型低密度脂蛋白作用细胞24h后小凹蛋白1的表达明显下降,细胞外信号调节激酶磷酸化活性显著增高,阻断氧化型低密度脂蛋白对细胞外信号调节激酶的激活可显著促进小凹蛋白1的表达。结论血管平滑肌细胞源性泡沫细胞小凹蛋白1的表达下调与氧化型低密度脂蛋白激活细胞外信号调节激酶及其介导的信号传导密切相关。

Aim To study the inhibitory effect of oxidized low density lipoprotein (ox-LDL) on the expression of caveolin-1 in vascular smooth muscle cell (SMC) and its relation with extracellular-signal regulated kinases 1/2 (ERK1/2). Methods Western blot was performed to evaluate the effects of ox-LDL (50 mg/L) or ox-LDL (50 mg/L) and PD98059 (25 μmol/L) on expression of caveolin-1and ERK1/2 in vascular SMC in different times. Results Ox-LDL (50 mg/L) obviously decreased caveolin-1 expression, and significantly increased ERK1/2 phosphorylation activity. However, the activation of ERK1/2 blocked by PD98059 significantly promoted caveolin-1 expression. Conclusions Downregulation of caveolin-1 expression in foam cell derived from vascular smooth muscle cell is involved in ERK1/2 phosphorylation activity and its signaling pathway activated by ox-LDL.