CAJ | 학술논문

目的探讨激动维甲类X受体(retinoid X receptor,RXR)对大鼠心肌细胞H9c2缺氧/复氧(hypoxia-reoxygenation,H/R)损伤的保护作用及其机制.方法将心肌细胞缺氧2h/复氧4h,建立H/R损伤模型.以9—顺式维甲酸(9-cis retinoid acid,c-RA)为RXR激动剂,HX531为RXR拮抗剂,实验随机(随机数字法)分4组:健康对照组(N组)、H/R损伤组、H/R+ 100nmol/L c-RA组(RA组)、H/R+ 100 nmoL/L c-RA +2.5 μmol/L HX531组(HX组),MTF法检测细胞活性,流式细胞技术检测细胞凋亡比例,荧光探针JC-1测定线粒体膜电位,Western blot印迹法检测Bcl-2、Bax及活性片段Caspase-9蛋白表达.所有计量资料以均数±标准差(-x±s)表示,采用单因素方差分析,Dennett-t检验,以P＜0.05为差异具有统计学意义.结果 c-RA明显抑制H/R损伤引起的细胞活性下降、凋亡增加、线粒体膜电位下降,Western blot印迹检测发现,H/R损伤组Bax、Caspase-9活性片段蛋白表达明显增加,Bcl-2表达明显下降,c-RA预处理后能明显下调Bax、Caspase-9活性片段蛋白表达及上调Bcl-2表达,而所有这些保护作用均被RXR拮抗剂HX531阻断.结论激动核受体RXR可以保护心肌细胞H/R氧化应激损伤,其机制与抑制线粒体凋亡通路有关.
목적 탐토격동유갑류X수체(retinoid X receptor,RXR)대대서심기세포H9c2결양/복양(hypoxia-reoxygenation,H/R)손상적보호작용급기궤제.방법 장심기세포결양2h/복양4h,건립H/R손상모형.이9—순식유갑산(9-cis retinoid acid,c-RA)위RXR격동제,HX531위RXR길항제,실험수궤(수궤수자법)분4조:건강대조조(N조)、H/R손상조、H/R+ 100nmol/L c-RA조(RA조)、H/R+ 100 nmoL/L c-RA +2.5 μmol/L HX531조(HX조),MTF법검측세포활성,류식세포기술검측세포조망비례,형광탐침JC-1측정선립체막전위,Western blot인적법검측Bcl-2、Bax급활성편단Caspase-9단백표체.소유계량자료이균수±표준차(-x±s)표시,채용단인소방차분석,Dennett-t검험,이P＜0.05위차이구유통계학의의.결과 c-RA명현억제H/R손상인기적세포활성하강、조망증가、선립체막전위하강,Western blot인적검측발현,H/R손상조Bax、Caspase-9활성편단단백표체명현증가,Bcl-2표체명현하강,c-RA예처리후능명현하조Bax、Caspase-9활성편단단백표체급상조Bcl-2표체,이소유저사보호작용균피RXR길항제HX531조단.결론 격동핵수체RXR가이보호심기세포H/R양화응격손상,기궤제여억제선립체조망통로유관.
Objective To determine the protective effects and potential mechanism of activating retinoid X receptor (RXR) on rat cardiomyocytes H9c2 against hypoxia/reoxygenation (H/R) induced oxidative injury.Methods The model of H-/R injury was established with hypoxia for 2 hours and reoxygenation for 4 hours in cardiomyocytes of H9c2,and 9-cis-retinoic acid (c-RA) was obtained as RXR agonist,and HX531 as RXR antagonist.Cultured cardiomyocytes were randomly (random number) divided into four groups:sham group,H/R group,H/R + c-RA-pretreated group (100 nmol/L c-RA) and H/R +c-RA + HX531-pretreated group (2.5 μmol/L HX531).We measured the cell viability by MTT (methyl thiazolyl tetrazolium),apoptosis rate of cardiomyocytes by using flow cytometry,and mitochondrial membrane potential by JC-1 fluorescent probe,protein levels of Bcl-2,Bax and cleaved Caspase-9 with Western blot.All measurement data were expressed as (-x ± s),and statistically analyzed using One-way ANOVA and Dunnett-t test.Differences were considered significant when P ＜ 0.05.Results Pretreatment with RXR agonist enhanced cell viability,reduced apoptosis ratio,stabilized mitochondrial membrane potential.Dot blotting experiments demonstrated that under H/R stress conditions,Bcl-2 protein level decreased,while Bax and cleaved Caspase-9 increased.The c-RA administration prior to H/R stress prevented these effects,however,overall protective effects of activating RXR on rat cardiomyocytes against H/R induced oxidative injury were abolished when pretreated with RXR pan-antagonist HX531.Conclusions Activating RXR has the protective effects against H/R injury in rat cardiomyocytes H9c2 through attenuation of mitochondria apoptosis signaling pathway.