Zhang Guoyong, Ma Zhimin, Ma Zheng, Liu Peilin, Zhang Lin, Lian Zheng, Guo Caixia
Department of Cardiovascular Center, Beijing Tongren Hospital, Capital Medical University, No. 3 Chongwenmennei Street, Dongcheng District, Beijing, 100730, China.
Cardiovasc Toxicol. 2025 Jan;25(1):97-109. doi: 10.1007/s12012-024-09950-6. Epub 2024 Dec 27.
Nuclear factor erythroid 2-related factor 2 (NRF2) is a redox-sensitive transcriptional factor that enables cells to resist oxidant responses, ferroptosis and inflammation. Here, we set out to probe the effects of NRF2 on cardiomyocyte injury under acute myocardial infarction (AMI) condition and its potential mechanism. Human cardiomyocytes were exposed to hypoxia/reoxygenation (H/R) to induce cell injury. qRT-PCR and western blot assays were used to detect the levels of mRNAs and proteins. Cardiomyocyte injury was determined by detecting the levels of lactate dehydrogenase and creatine Kinase MB (CK-MB). Cell apoptosis was investigated by flow cytometry and related markers. Levels of IL-6, IL-10, and TNF-α were measured by ELISA. Cell ferroptosis was assessed by detecting the production of reactive oxygen species (ROS), malonaldehyde (MDA), reduced glutathione/oxidized glutathione disulfide (GSH/GSSG) ratio, Fe + content, and related regulators. The interaction between NRF2 and the suppressor of zest 12 (SUZ12) was analyzed by using dual-luciferase reporter and RNA immunoprecipitation assays. AMI rat models were established for in vivo analysis. NRF2 was lowly expressed in AMI patients and H/R-induced cardiomyocytes. Forced expression of NRF2 reduced H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis. Moreover, NRF2 overexpression improved cardiac function and injury in vivo. Mechanistically, SUZ12 bound to the promoter of NRF2 and promoted its expression. Further functional analyses showed that SUZ12 overexpression reduced H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis, which were reversed by NRF2 silencing. SUZ12-increased NRF2 suppressed H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis in vitro and improved cardiac functions in rats with I/R injury, suggesting the potential cardioprotective effect of NRF2 in cardiac injury during AMI.
核因子红细胞2相关因子2（NRF2）是一种对氧化还原敏感的转录因子，可使细胞抵抗氧化应激反应、铁死亡和炎症。在此，我们着手探究NRF2在急性心肌梗死（AMI）条件下对心肌细胞损伤的影响及其潜在机制。将人心肌细胞暴露于缺氧/复氧（H/R）环境中以诱导细胞损伤。采用qRT-PCR和蛋白质印迹分析检测mRNA和蛋白质水平。通过检测乳酸脱氢酶和肌酸激酶MB（CK-MB）水平来确定心肌细胞损伤。通过流式细胞术和相关标志物研究细胞凋亡。采用酶联免疫吸附测定法（ELISA）检测白细胞介素-6（IL-6）、白细胞介素-10（IL-10）和肿瘤坏死因子-α（TNF-α）水平。通过检测活性氧（ROS）、丙二醛（MDA）、还原型谷胱甘肽/氧化型谷胱甘肽二硫化物（GSH/GSSG）比值、铁离子（Fe⁺）含量及相关调节因子来评估细胞铁死亡。利用双荧光素酶报告基因和RNA免疫沉淀试验分析NRF2与zeste 12抑制因子（SUZ12）之间的相互作用。建立AMI大鼠模型进行体内分析。NRF2在AMI患者和H/R诱导的心肌细胞中低表达。NRF2的强制表达减轻了H/R诱导的心肌细胞损伤、凋亡、炎症和铁死亡。此外，NRF2过表达改善了体内心脏功能和损伤。机制上，SUZ12与NRF2启动子结合并促进其表达。进一步的功能分析表明，SUZ12过表达减轻了H/R诱导的心肌细胞损伤、凋亡、炎症和铁死亡，而NRF2沉默可逆转这些作用。SUZ12上调的NRF2在体外抑制了H/R诱导的心肌细胞损伤、凋亡、炎症和铁死亡，并改善了缺血/再灌注（I/R）损伤大鼠的心脏功能，提示NRF2在AMI期间心脏损伤中具有潜在的心脏保护作用。
