CGRP通过抑制p38MAPK/NOX4通路保护氧化应激诱导的血管内皮细胞损伤

Inhibition of p38MAPK/NOX4 Signal Pathway Mediates the Protection of CGRP on the HUVECs Injured by Oxidative Stress

目的观察降钙素基因相关肽(CGRP)对氧化应激损伤血管内皮细胞的保护作用及其对p38MAPK/NOX4信号通路的抑制作用。方法体外培养人脐静脉内皮细胞株(HUVECs),外源性给予过氧化氢(H2O2)或血管紧张素Ⅱ(AngⅡ)作为氧化刺激因素,CGRP作为保护剂处理细胞。噻唑蓝比色法(MTT)观察HUVECs活力;流式细胞仪(FCM)观察分析HUVECs增殖指数的改变;Western Blot和Real-time PCR分别检测p38MAPK、NADPH氧化酶4(NOX4)蛋白和mRNA的表达。结果 500μmol/L H2O2或100 nmol/L AngⅡ能浓度依赖性地降低HUVECs活力和增殖指数(PI);CGRP可以显著增加HUVECs活力和及其PI。同时,H2O2、AngⅡ均能诱导p38 MAPK磷酸化,并能上调NOX4蛋白和mRNA表达,p38 MAPK阻断剂能部分增强CGRP抑制AngⅡ或H2O2诱导的NOX4的表达。结论 CGRP对内外源性的氧化应激损伤HUVECs的保护机制可能与抑制p38MAPK/NOX4信号通路有关。

Objective To study the protection of cacitonin gene-related peptide（ CGRP） on human umbilical vein endothelial cells（ HUVECs） injured by oxidative stress,and explore whether the mechanism involved in inhibition of p38 MAPK / NOX4 signal pathway. Methods HUVECs cell line were cultured in vitro,angiotensin Ⅱ（ AngⅡ） or hydrogen peroxide（ H2O2） serves as the gent of oxidative stress,CGRP serves as the protection agent. MTT was used to test the viability of cells,distribution of cell cycles and proliferation of cells were observed by flow cytometry. The protein or mRNA expressions of the p38 MAPK、NADPH oxidase 4（ NOX4） was measured by Western blot or RT-PCR,respectively.Rethods Compared with control group,AngⅡ or H2O2 decreased the cell viability and proliferation index（ PI） dose-dependently,which were inhibited by 100 nmol / L CGRP; Meantime,the level of phosphated p38 MAPK was induced by AngⅡ or H2O2,and increased the expression of NOX4. Pretreatment with CGRP and SB 203580 can inhibit the up-regulation of NOX4 induced by AngⅡ or H2O2. Conclusions The protection of CGRP on the HUVECs injured by oxidative stress from in vitro（ H2O2） or in vivo（ AngⅡ） is related to inhibition of p38MAPK/ NOX4 signal pathway.