Vitamin D induces nitric oxide production in cultured endothelial cells / 中华实用儿科临床杂志

ABSTRACT

Objective To test the effects of Vitamin D (VitD) on endothelial nitric oxide(NO) production and to study the signal pathway leading to NO release.Methods In vitro cultured human umbilical vein endothelial cells (HUVEC) were treated with various concentrations of VitD(0 mmol/L,0.01 mmol/L,0.10 mmol/L,1.00 mmol/L,10.00 mmol/L) for 60 min,and VitD at concentration of 1.00 mmol/L at different time points (30 min,60 min,90 min,120 min).The effect of VitD on NO production in presence of VitD receptor(VDR) agonist(ZK191784) or antagonist(ZK159222) for 60 min were examined in cell culture supernatant with kit for the detection of nitric oxide fluorescent probe(DAF-FM DA).HUVEC was cultured with VitD in presence of VDR agonist or antagonist for 60 min,and the effect of VitD on NO production with DAF-FM DA and the protein expression and phosphorylation of Caveolin-1 and endothelial nitric oxide synthase(eNOS) were detected by Western blot,respectively.Results VitD caused a concentration-dependent increase in NO production.The maximum effect was observed at a concentration of 1.0 mmol/L and the optimal time of stimulation was 60 min.Effects induced by VitD were enhanced by VDR agonist,and abolished by antagonist.VitD and VDR agonist maintained the expression of Caveolin-1 at the same low phosphorylation level the same as normal,increased the phosphorylated level of eNOS.However,VDR antagonist increased the phosphorylation of caveolin-l,but reduced the level of eNOS phosphorylation,respectively.Conclusions VitD can induce a significant increase in endothelial NO production through VDR.VitD interaction with VDR causes the low phosphorylation of caveolin-1 leading to eNOS activation and NO production.