1,25-二羟维生素D3对软脂酸诱导的胰岛素抵抗血管内皮细胞功能的影响

The role of 1,25-dihydroxyvitamin D3 in palmitic acid induced insulin resistance in human umbilical vein endothelial cells

目的:探讨1,25-二羟维生素D3[1,25(OH)2D3]对软脂酸(PA)诱导的人脐静脉内皮细胞(HUVECs)的胰岛素抵抗的影响及其可能作用机制。方法:用含0.3、0.4、0.5、0.6、0.7、0.8、0.9 mmol/L PA的DMEM培养基培养HUVECs,建立胰岛素抵抗内皮细胞模型。分别用0、0.01、0.1、1.0、10、100 nmol/L 1,25(OH)2D3干预,硝酸盐/亚硝酸盐荧光试剂盒测定NO含量,Western blot法测定pAkt及peNOS蛋白的表达,qPCR法测定VDR、ET-1的表达。结果:0.6 mmol/L的PA培养HUVECs 18 h后,培养液中的葡萄糖浓度耗减显著低于对照组,细胞活力降低,胰岛素抵抗的内皮细胞模型建立。PA干预后NO含量较对照组HUVECs减少(P<0.05),1 nmol/L 1,25(OH)2D3干预胰岛素抵抗的内皮细胞后NO含量增加,在1 min时NO量达最大值。1 nmol/L浓度1,25(OH)2D3干预胰岛素抵抗的内皮细胞后peNOS及pAkt的蛋白表达量明显增加(P<0.05),ET-1的mRNA表达水平明显减少(P<0.05)。结论:1,25(OH)2D3增加PA诱导的胰岛素抵抗血管内皮细胞peNOS、pAkt的表达,增加NO产生,降低ET-1的表达,可能对胰岛素抵抗的血管内皮细胞存在一定的保护作用。

Objective:To investigate the effect of 1,25-dihydroxyvitamin D3[1,25(OH)2D3]on the insulin resistance of human umbilical vein endothelial cells(HUVECs)induced by palmitic acid(PA)and its possible mechanism.Methods:HUVECs were cultured in DMEM medium containing(0.3,0.4,0.5,0.6,0.7,0.8,0.9 mmol/L)PA to establish insulin resistance endothelial cell model.0,0.01,0.1,1,10,100 nmol/L 1,25(OH)2D3 intervention,nitrate/nitrite fluorescence kit to determine the content of NO,Western blot to determine the expression of pAkt and penos protein.The expression of VDR and ET-1 was detected by qPCR.Results:after HUVECs were cultured with 0.6 mmol/L PA for 18 hours,the glucose concentration in the culture medium was significantly lower than that in the control group,the cell viability was reduced,and the endothelial cell model of insulin resistance was established.The NO content of HUVECs in PA group was lower than that in control group(P<0.05).After the intervention of 1 nmol/L 1,25(OH)2D3 on insulin resistant endothelial cells,the protein expression of peNOS and pAkt increased significantly(P<0.05),and the mRNA expression of ET-1 decreased significantly(P<0.05).Conclusion:1,25(OH)2D3 can increase the expression of peNOS and pAkt,increase the production of NO and decrease the expression of ET-1,which may have a protective effect on insulin resistant vascular endothelial cells.