【摘要】 目的细胞水平探究维生素D（VD）对血管内皮细胞的保护作用。方法采用肿瘤坏死因子α（TNF-α）诱导内皮损伤和黏附分子表达;维生素D采用最具活性形式的骨化三醇;利用流式细胞术检测血管细胞黏附分子-1（VCAM-1）表达水平;荧光显微镜观察绿色荧光加载的THP-1单核细胞与内皮细胞的黏附作用;Western blot检测VD受体（VDR）、p38、磷酸化p38蛋白水平。结果与对照组比较,TNF-α组内皮细胞VCAM-1表达增高（P<0.05）、内皮细胞与单核细胞黏附作用增加（P<0.05）。当内皮细胞预孵育10^-9、10^-8、10^-7、10^-6 mol/L骨化三醇后,TNF-α诱导的内皮细胞VCAM-1的表达降低,与单核细胞之间的黏附作用减弱（P<0.05）。特异性siRNA敲低VDR蛋白水平后,骨化三醇对内皮细胞VCAM-1表达的抑制作用减弱,内皮细胞与单核细胞的黏附作用减弱（P<0.05）。TNF-α促进内皮细胞p38蛋白磷酸化、而骨化三醇抑制TNF-α诱导的内皮细胞p38蛋白磷酸化（P<0.05）。特异性siRNA敲低VDR蛋白水平后,骨化三醇对TNF-α诱导的内皮细胞p38蛋白磷酸化及VCAM-1的表达和单核细胞黏附抑制作用均降低（P<0.05）。结论维生素D3通过VDR-p38信号途径抑制TNF-α诱导的血管内皮细胞VCAM-1蛋白表达,以及抑制内皮细胞与单核细胞黏附作用。更多还原

【Abstract】 Objective To study the protective effect of vitamin D（VD）on vascular endothelial cells in cellular level.Methods The tumor necrosis factor-α （TNF-α）was used to induce the endothelial injury and the expression of adhesion molecules.Vitamin D adopted the most active form of calcitriol.The flow cytometry was used to detect the expression level of VCAM-1;the fluorescence microscopy was used to observe the adhesion effect of THP-1 monocytes loaded with green fluorescence and endothelial cells;the Western blot was used to detect the levels of vitamin D receptor（VDR）,p38,phosphorylated p38 protein.Results Compared with the control group,the endothelial cellular VCAM-1 expression level in the TNF-α group was increased（P<0.05）and the adhesive effect of endothenial cells to monocytes was increased（P<0.05）.When endothelial cells preincubating 10^-9,10^-8,10^-7,10^-6 mol/L calcitriol,the expression level of endothelial cellular VCAM-1 induced by TNF-α was decreased,and its adhesive effect to monocytes was weakened（P<0.05）.After specific siRNA knocking down the VDR protein level,the inhibiting effect of calcitriol on endothelial cellular VCAM-1 expression was weakened and the adhesive effect of endothelial cells to monocytes was weakened（P<0.05）.TNF-α promoted the phosphorylation of p38 protein in endothelial cells,while calcitriol inhibited the phosphorylation of endothelial cellular p38 protein induced by TNF-α（P<0.05）.After specific siRNA knocking down VDR protein level,the effect of calcitriol on p38 protein phosphorylation induced by TNF-α and VCAM-1 expression as well as monocytes adhesive inhibiting effect were decreased（P<0.05）.Conclusion Calcitriol inhibits TNF-α induced endothelial cellular VCAM-1 protein expression and inhibits the adhesive effect of endothelial cells to mononcytes through VDR-p38 signaling pathway.更多还原