肥厚预适应通过去乙酰化异柠檬酸脱氢酶 2 减轻心肌梗死后损伤。
Hypertrophic preconditioning attenuates post-myocardial infarction injury through deacetylation of isocitrate dehydrogenase 2.
机构信息
Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
NHC Key Laboratory of Viral Heart Diseases, Shanghai, 200032, China.
出版信息
Acta Pharmacol Sin. 2021 Dec;42(12):2004-2015. doi: 10.1038/s41401-021-00699-0. Epub 2021 Jun 23.
Ischemic preconditioning induced by brief periods of coronary occlusion and reperfusion protects the heart from a subsequent prolonged ischemic insult. In this study we investigated whether a short-term nonischemic stimulation of hypertrophy renders the heart resistant to subsequent ischemic injury. Male mice were subjected to transient transverse aortic constriction (TAC) for 3 days followed aortic debanding on D4 (T3D4), as well as ligation of the left coronary artery to induce myocardial infarction (MI). The TAC preconditioning mice showed markedly improved contractile function and significantly reduced myocardial fibrotic area and apoptosis following MI. We revealed that TAC preconditioning significantly reduced MI-induced oxidative stress, evidenced by increased NADPH/NADP ratio and GSH/GSSG ratio, as well as decreased mitochondrial ROS production. Furthermore, TAC preconditioning significantly increased the expression and activity of SIRT3 protein following MI. Cardiac-specific overexpression of SIRT3 gene through in vivo AAV-SIRT3 transfection partially mimicked the protective effects of TAC preconditioning, whereas genetic ablation of SIRT3 in mice blocked the protective effects of TAC preconditioning. Moreover, expression of an IDH2 mutant mimicking deacetylation (IDH2 K413R) in cardiomyocytes promoted myocardial IDH2 activation, quenched mitochondrial reactive oxygen species (ROS), and alleviated post-MI injury, whereas expression of an acetylation mimic (IDH2 K413Q) in cardiomyocytes inactivated IDH2, exacerbated mitochondrial ROS overload, and aggravated post-MI injury. In conclusion, this study identifies TAC preconditioning as a novel strategy for induction of an endogenous self-defensive and cardioprotective mechanism against cardiac injury. Therapeutic strategies targeting IDH2 are promising treatment approaches for cardiac ischemic injury.
缺血预处理通过短暂的冠状动脉闭塞和再灌注诱导,可保护心脏免受随后的长时间缺血损伤。在这项研究中,我们研究了短暂的非缺血性肥大刺激是否使心脏对随后的缺血性损伤产生抗性。雄性小鼠接受短暂的主动脉缩窄(TAC)3 天,然后在第 4 天进行主动脉松解(T3D4),以及结扎左冠状动脉以诱导心肌梗死(MI)。TAC 预处理小鼠在 MI 后表现出明显改善的收缩功能,以及显著减少的心肌纤维化面积和细胞凋亡。我们揭示 TAC 预处理显著降低了 MI 诱导的氧化应激,表现为 NADPH/NADP 比和 GSH/GSSG 比增加,以及线粒体 ROS 产生减少。此外,TAC 预处理在 MI 后显著增加了 SIRT3 蛋白的表达和活性。通过体内 AAV-SIRT3 转染实现心脏特异性 SIRT3 基因过表达部分模拟了 TAC 预处理的保护作用,而在小鼠中遗传敲除 SIRT3 则阻断了 TAC 预处理的保护作用。此外,在心肌细胞中表达模拟去乙酰化的 IDH2 突变体(IDH2 K413R)促进了心肌 IDH2 的激活,抑制了线粒体活性氧(ROS),并减轻了 MI 后的损伤,而在心肌细胞中表达乙酰化模拟物(IDH2 K413Q)则使 IDH2 失活,加剧了线粒体 ROS 过载,并加重了 MI 后的损伤。总之,本研究确定 TAC 预处理是一种诱导内源性自我防御和心脏保护机制对抗心脏损伤的新策略。针对 IDH2 的治疗策略是治疗心脏缺血性损伤的有前途的治疗方法。