红景天苷对血管紧张素Ⅱ诱导心肌成纤维细胞纤维化的保护作用

Protective effect of salidroside on angiotensin II-induced fibrosis in cardiac fibroblasts

背景:目前已有研究表明红景天苷对多器官纤维化具有改善作用,但红景天苷对血管紧张素Ⅱ引起心肌成纤维细胞纤维化的保护作用尚不明确。目的:探究红景天苷对血管紧张素Ⅱ诱导的SD大鼠心肌成纤维细胞氧化应激及细胞外基质沉积的保护作用及其作用机制。方法:血管紧张素Ⅱ诱导心肌成纤维细胞纤维化,实验分为5组:正常对照组;模型组(培养基血管紧张素Ⅱ终浓度为1μmol/L);红景天苷低剂量和高剂量组(加入红景天苷50,100μmol/L处理2 h,再加入血管紧张素Ⅱ共同孵育48 h);SIRT1抑制剂组(加入SIRT1抑制剂EX52710μmol/L处理2 h,再加高剂量红景天苷处理2 h,再加血管紧张素Ⅱ共同孵育48 h)。使用CCK8法检测各组细胞活力,Transwell检测细胞迁移率,DCFH-DA荧光探针检测细胞内活性氧水平,试剂盒检测细胞内丙二醛含量、超氧化物歧化酶和过氧化氢酶活性;采用Western blot和qRT-PCR法检测心肌成纤维细胞纤维化相关mRNA和蛋白的表达水平。结果与结论:①经Vimentin荧光鉴定实验细胞为心肌成纤维细胞;②与正常对照组相比,模型组细胞活力、细胞迁移率、活性氧水平、丙二醛含量显著增加,超氧化物歧化酶和过氧化氢酶活性明显降低,LOXL2、α-SMA、胶原蛋白Ⅰ、胶原蛋白ⅢmRNA和蛋白表达显著升高,SIRT1蛋白表达水平明显降低(均P<0.01);与模型组相比,红景天苷低、高剂量组上述指标呈现相反的变化(均P<0.05),且红景天苷呈剂量依赖性调控;与红景天苷组相比,SIRT1抑制剂组细胞迁移率、α-SMA蛋白表达水平显著增加(均P<0.001);③结果表明,红景天苷对血管紧张素Ⅱ诱导的心肌成纤维细胞具有保护作用,能够剂量依赖性地抑制氧化应激和细胞外基质沉积。

BACKGROUND:Previous studies have shown that salidroside has an ameliorative effect on multi-organ fibrosis.However,the protective effect of salidroside on angiotensin ii-induced fibrosis in cardiac fibroblasts is unclear.OBJECTIVE:To investigate the protective effects of salidroside on angiotensin ii-induced oxidative stress and extracellular matrix deposition in cardiac fibroblasts of Sprague-Dawley rats and its mechanism of action.METHODS:Angiotensin II was used to induce fibrosis in cardiac fibroblasts,and there were five experimental groups:normal control group,model group(final concentration of angiotensin II in culture medium was 1μmol/L),salidroside low and high dose groups(treatment with salidroside 50,100μmol/L for 2 hours,followed by co-incubation with angiotensin II for 48 hours),SIRT1 inhibitor group(treatment with SIRT1 inhibitor EX52710μmol/L for 2 hours,followed by high dose of salidroside for 2 hours and then co-incubation with angiotensin II for 48 hours).The cell viability was detected using the cell counting kit-8 method,the cell migration rate was detected by Transwell,the intracellular reactive oxygen species level was detected by DCFH-DA fluorescent probe,and the intracellular malondialdehyde content,superoxide dismutase and catalase activities were detected by relevant kits.The protein and mRNA expression levels of SIRT1,LOXL2,α-SMA,type I collagen and type III collagen were detected by western blot and qRT-PCR,respectively.RESULTS AND CONCLUSION:The cells were identified as cardiac fibroblasts by Vimentin fluorescence.Compared with the normal control group,cell viability,cell migration rate,reactive oxygen species level,and malondialdehyde content were significantly increased,superoxide dismutase and catalase activities were significantly decreased,LOXL2,α-SMA,type I collagen,type III collagen mRNA and protein expression were significantly increased,and SIRT1 protein expression level was significantly decreased in the model group(all P<0.01).Compared with the model group,the above indexes showed opposite changes in the salidroside low and high dose groups(all P<0.05).Moreover,salidroside showed dose-dependent regulation.Compared with salidroside groups,cell migration rate andα-SMA protein expression level were significantly increased in the SIRT1 inhibitor group(both P<0.001).To conclude,salidroside has a protective effect on angiotensin II-induced cardiac fibroblasts and can dose-dependently inhibit oxidative stress and extracellular matrix deposition.