[ ABSTRACT] AIM:To investigate the effects of sinapic acid ( SA) on the proliferation and apoptosis of rat vas-cular smooth muscle cells (VSMCs) induced by high glucose (HG).METHODS:Cultured A7r5 cells were randomly di-vided and treated as indicated.The cell viability was determined by MTT assay.DNA synthesis was measured by BrdU as-say.Cell cycle progression and cell apoptotic rate were determined by flow cytometry analysis.The levels of reactive oxygen species (ROS) were detected by ELISA.The protein levels of cyclin D1, P21, P27, phosphorylated protein kinase C (p-PKC), p-P38 andβ-actin were evaluated by Western blot.RESULTS:Compared with control group, the viability of A7r5 cells was significantly enhanced, the DNA synthesis was increased, the cell cycle progression was promoted, the levels of ROS were elevated, the cell apoptotic rate was reduced, the protein expression of P21 and P27 was decreased, and the pro-tein levels of cyclin D1, p-PKC and p-P38 were increased in HG group (all P<0.05).These effects were reversed by SA (0.1, 1 and 10 μmol/L) treatment in a dose-dependent manner (all P<0.05).Both P38 inhibitor SB203580 and PKC inhibitor chelerythrine significantly inhibit HG-induced PKC/P38 activation and cell viability ( P <0.05).CONCLU-SION:SA inhibits HG-induced VSMCs proliferation and promotes cell apoptosis via reducing PKC/P38 activation.%目的：探讨芥子酸对高糖诱导下大鼠血管平滑肌细胞（ vascular smooth muscle cells，VSMCs）增殖和凋亡的影响及机制。方法：将培养的A7r5细胞随机分组处理，MTT法检测细胞活力，BrdU法检测细胞DNA合成，流式细胞术检测细胞周期进程和细胞凋亡，ELISA检测细胞活性氧簇（ reactive oxygen species，ROS）生成，West－ern blot检测cyclin D1、P21和P27等蛋白的表达，以及蛋白激酶C（ PKC）和P38的磷酸化水平。结果：与正常组比较，高糖组细胞活力显著升高，DNA合成加快，细胞周期加快，P21和P27表达降低，cyclin D1表达增加，ROS水平增加，细胞凋亡率降低，p－PKC和p－P38蛋白水平增加（ P＜0．05）。而芥子酸（0．1、1和10μmol／L）处理引起细胞增殖活性降低，DNA合成减弱，细胞周期受阻，P21和P27表达增加，cyclin D1表达降低，ROS水平降低，细胞凋亡率升高，p－PKC和p－P38蛋白水平降低，且呈一定浓度依赖性（ P＜0．05）。 P38抑制剂SB203580和PKC抑制剂chelerythrine均显著抑制高糖诱导的PKC／P38活化和细胞活力（ P＜0．05）。结论：芥子酸可通过抑制PKC／P38激活降低高糖诱导的VSMCs增殖，并促进细胞凋亡。
展开▼
