O-GlcNAc糖基化对转录因子CREB活性和心肌细胞形态的影响  

Regulation of CREB activity and morphology of myocardial cells by O-GlcNacylation

作　　者：施林生[1] 黄建飞[1] 卢辉和[1] 陈小丽[1] 郑扣龙[1] 林刚[1] 于彬[2] 周艳[3] 

机构地区：[1]南通市第一人民医院心内科,江苏南通226000 [2]江苏省神经再生重点实验室,江苏南通226000 [3]南通大学医学院生化教研室,江苏南通226000

出　　处：《南京医科大学学报（自然科学版）》2013年第12期1658-1663,共6页Journal of Nanjing Medical University(Natural Sciences)

基　　金：国家自然科学基金(31100761);南通市科技计划项目(BK2011057)

摘　　要：目的:研究心肌缺血早期升高的O-GlcNAc糖基化是否通过促进转录因子CAMP反应元件结合蛋白(CREB)的活性而引起心肌细胞形态变化。方法:在HEK-293T细胞内过表达调控O-GlcNAc糖基化的酶O-连接N-乙酰氨基葡萄糖转移酶(OGT)和O-连接N-乙酰氨基葡萄糖苷酶(OGA),Western blot检测细胞内的O-GlcNAc糖基化水平和CREB的磷酸化。原代培养大鼠心肌细胞,药物DON和PUGNAc改变细胞内的O-GlcNAc糖基化水平,光镜下观察细胞形态,Western blot检测细胞内的O-GlcNAc糖基化水平和CREB的磷酸化。结果:在HEK-293T细胞和原代培养的大鼠心肌细胞中改变O-GlcNAc糖基化水平,CREB磷酸化也随之改变,两者呈正相关。升高原代大鼠心肌细胞内的O-GlcNAc糖基化水平,心肌细胞数目减少,形态增大。结论:O-GlcNAc糖基化调节CREB的活性,两者呈正相关。心肌缺血早期升高的O-GlcNAc糖基化很可能通过促进CREB的活性而引起心肌细胞体积增大密度下降,可能是导致心肌重构的重要原因。Objective：To study whether increase of O-GlcNAcylation in acute myocardial ischemia causes morphology change of myocardial cells by promoting activity of transcriptional factor CREB. Methods：HEK-293T cells were overexpressed with enzymes OGT and OGA,which regulate O-GlcNAcylation. Total O-GlcNAcylation levels and CREB phosphorylation were detected by Western- blot. Primary cultured rat myocardial cells were treated with drugs DON and PUGNAc to regulate intracellular O-GlcNAcylation levels. Cells morphology was observed by light microscope,and O-GlcNAcylation levels and phosphorylation of CREB were detected by Western-blot. Results：In HEK-293T cells and primary cultured rat myocardial cells,the CREB phosphorylation was positively correlated to the O-GlcNAcylation level. The elevation of O-GlcNAcylation in primary rat myocardial cells reduced the number of cells,but increased sive of the cells. Conclusion：O-GlcNAcylation regulates the activity of CREB positively. The elevated O- GlcNAcylation in acute myocardial ischemia is likely to cause the increase of myocardial cell size and the decease of cell density by promoting the activity of CREB,which may be one of the most important factors leading to myocardial remodeling.

关 键 词：O-GlcNAc糖基化 CREB 心肌缺血 

分 类 号：R329.26[医药卫生—人体解剖和组织胚胎学]