非对称性二甲基精氨酸对人脐静脉内皮细胞黏附分子-1表达的影响及L-精氨酸的拮抗作用

Effects of asymmetric dimethylarginine on the expression of sICAM-1 in human umbilical vein endothelial cells and the antagonism of L-arginine

目的 :探讨非对称性二甲基精氨酸 (ADMA)对人脐静脉内皮细胞 (HUVECs)表达可溶性细胞间黏附分子- 1(sICAM 1)的影响 ,并观察不同浓度L- 精氨酸 (L- arg)对ADMA效应的拮抗作用。方法 :以不同浓度的ADMA与HUVECs共育或固定浓度的ADMA加不同浓度的L -arg与HUVECs共育 2 4h ,用ELISA法检测培养液中sICAM 1的浓度。结果 :ADMA呈剂量依赖性增加HUVECs表达sICAM 1(P <0 .0 5 ) ,接近生理范围的ADMA对内皮功能没有明显的影响 ;外源性补充L arg可逆转ADMA的效应 ,且呈剂量依赖性 (P <0 .0 5 ) ,但当外源性L arg的剂量大到一定程度时 ,内皮功能并不能得到进一步改善。直线相关分析显示培养液中sICAM 1的浓度和ADMA的浓度明显正相关 (r=0 .943 ,P <0 .0 1)。结论 :ADMA可通过增加内皮细胞表达sICAM -1来导致内皮功能紊乱 ,且内皮功能紊乱的程度与ADMA的浓度有关 ;外源性补充L-arg可逆转ADMA的效应 ;药物调节ADMA的浓度可能是防治心血管疾病的一个新目标。

Objective:To investigate the effects of asymmetric dimethylarginine on the expression of soluble intercellular adhesion molecule-1 (sICAM-1) in human umbilical vein endothelial cells (HUVECs), and observe whether L-arginine (L-arg) of different dosage can antagonize the effects of ADMA.Methods:When ADMA or ADMA plus L-arg were incubated with HUVECs for 24hs,the levels of sICAM-1 in conditioned medium were measured by means of Enzyme-Linked Immunosorbent assay.Results:①ADMA can increase HUVECs to express sICAM-1 in a concentration-dependent manner (P<0.05), but these effects were gradually dismissed after giving the increasing dosage of L-arg. ②Compared with the control group, the group of ADMA 1μmol/l had no significant difference in the expression of sICAM-1. Except this group, the other four ADMA groups all had significant difference compared with the control group (P<0.05, respectively). Among the five ADMA groups, they all had significant difference each other (P<0.05, respectively). ③When the added L-arg/ADMA ratio is big enough (L-arg/ADMA>100), there are no more improvements of endothelial function. ④The levels of sICAM-1 in conditioned medium was significantly positive correlation with the levels of ADMA (r= 0.943, P<0.01).Conclusion:①ADMA can induce endothelial dysfunction by means of increasing endothelial cells to express sICAM-1. The degree of endothelial dysfunction is significantly positive correlation with the levels of ADMA. ②Give exogenous L-arginine can antagonize the effects of ADMA. ③The new aim to prevent and treat the cardiac disease may be use medicine to regulate the level of ADMA.