过氧化物酶体增殖物激活受体γ共激活因子1α抑制主动脉瓣瓣膜间质细胞活化的作用及机制研究  

Role and mechanism of peroxisome proliferator-activated receptor gamma coactivator 1αin inhibiting aortic valve interstitial cell activation

作　　者：珊措吉 李君丽[1,2] 陈茂[1,2] Shancuoji;LI Junli;CHEN Mao(Department of Cardiology,West China Hospital,Sichuan University,Chengdu,Sichuan 610041,P.R.China;Laboratory of Cardiac Structure and Function,Institute of Cardiovascular Diseases,West China Hospital,Sichuan University,Chengdu,Sichuan 610041,P.R.China)

机构地区：[1]四川大学华西医院心脏内科,成都610041 [2]四川大学华西医院心血管疾病研究所心脏结构与功能研究室,成都610041

出　　处：《华西医学》2024年第9期1387-1397,共11页West China Medical Journal

基　　金：四川省自然科学基金(2023NSFSC1339)。

摘　　要：目的探讨过氧化物酶体增殖物激活受体γ共激活因子1α(peroxisome proliferator-activated receptor gamma coactivator 1α,PGC-1α)在主动脉瓣狭窄中心环节之瓣膜间质细胞活化中的作用及机制。方法分离培养大鼠原代主动脉瓣瓣膜间质细胞(aortic valve interstitial cell,AVIC)并以转化生长因子β1(transforming growth factorβ1,TGF-β1)30 ng/mL刺激其活化,观察PGC-1α的表达变化;利用过表达腺病毒上调PGC-1α表达水平或小分子抑制剂GW9662抑制PGC-1α功能观察AVIC活化程度变化;筛选其可能的下游分子机制;在人AVIC原代细胞中进一步验证表型。结果TGF-β1诱导AVIC活化后,与空白对照组(1.00±0.18)相比,诱导后PGC-1α的表达水平下降(24 h:0.31±0.10;48 h:0.32±0.06;72 h:0.20±0.07;P<0.05);过表达PGC-1α抑制由TGF-β1刺激诱导的AVIC活化(骨膜蛋白:3.17±0.64 vs.1.45±0.54,P<0.05;α-平滑肌肌动蛋白:0.77±0.11 vs.0.28±0.06,P<0.05),抑制剂GW9662的使用则促进AVIC活化(骨膜蛋白:2.20±0.68 vs.7.99±2.50,P<0.05);随后筛选出PGC-1α可能通过下调钙调蛋白依赖性蛋白激酶1δ(calcium/calmodulin-dependent protein kinase 1δ,CAMK1δ)表达而抑制AVIC活化(0.97±0.04 vs.0.74±0.11,P<0.05),下调CAMK1δ表达则缓解AVIC活化程度(骨膜蛋白:1.76±0.11 vs.0.99±0.20,P<0.05),其可能的机制为下调了活性氧(reactive oxygen species,ROS)的堆积(778.3±139.4 vs.159.3±43.2,P<0.05)而抑制了哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号通路的激活。最后,在人AVIC的活化表型中验证过表达PGC-1α具有保护作用(骨膜蛋白:2.73±0.53 vs.1.63±0.14,P<0.05;结缔组织生长因子:1.27±0.04 vs.0.48±0.09,P<0.05)。结论AVIC活化进程中PGC-1α表达明显降低,上调PGC-1α表达显著抑制了AVIC活化程度即PGC-1α在AVIC活化进程中发挥保护性作用,其机制为抑制了CAMK1δ-ROS-mTOR通路的激活。由此可知,基于PGC-1α表达水平的干预措施是主动脉瓣狭窄的新潜在Objective To investigate the role and mechanism of peroxisome proliferator-activated receptor gamma coactivator 1α(PGC-1α)in the activation of aortic valve interstitial cells(AVICs)in aortic stenosis.Methods Isolating primary AVICs and stimulating their activation with transforming growth factorβ1(TGF-β1,30 ng/mL),the expression of PGC-1αwas detected.The activation of AVICs induced by TGF-β1 was observed after overexpression of PGC-1αby adenovirus or inhibition of PGC-1αfunction by GW9662.The possible downstream molecular mechanism of PGC-1αin AVICs activation was screened.Finally,the phenotype was further verified in primary human AVICs.Results The expression of PGC-1αdecreased after the activation of AVICs induced by TGF-β1(control group:1.00±0.18;24 h:0.31±0.10;48 h:0.32±0.06;72 h:0.20±0.07;P<0.05).Specific overexpression of PGC-1αby adenovirus inhibited the activation of AVICs induced by TGF-β1 stimulation(periostin:3.17±0.64 vs.1.45±0.54,P<0.05;α-smooth muscle actin:0.77±0.11 vs.0.28±0.06,P<0.05).On the contrary,inhibition of PGC-1αfunction by GW9662 promoted the activation of AVICs(periostin:2.20±0.68 vs.7.99±2.50,P<0.05).Subsequently,it was found that PGC-1αmight inhibit the activation of AVICs through downregulating the expression of calcium/calmodulin-dependent protein kinase(CAMK1δ)(0.97±0.04 vs.0.74±0.11,P<0.05),and downregulating the expression of CAMK1δalleviated the activation of AVICs(periostin:1.76±0.11 vs.0.99±0.20,P<0.05).The possible mechanism was that the activation of mammalian target of rapamycin(mTOR)signaling pathway was inhibited by reducing the accumulation of reactive oxygen species(ROS)(778.3±139.4 vs.159.3±43.2,P<0.05).Finally,the protective effect of PGC-1αoverexpression was verified in the activated phenotype of human AVICs(periostin:2.73±0.53 vs.1.63±0.14,P<0.05;connective tissue growth factor:1.27±0.04 vs.0.48±0.09,P<0.05).Conclusions The expression of PGC-1αsignificantly decreases during the activation of AVICs induced by TGF-β1.The overex

关 键 词：主动脉瓣狭窄 瓣膜间质细胞活化 过氧化物酶体增殖物激活受体γ共激活因子1α 钙调蛋白依赖性蛋白激酶1δ 

分 类 号：R542.52[医药卫生—心血管疾病]