Yang Jian, Zhang Mengting, Liu Li, Zhang Peiyue, Liu Haiyin, Yang Zishu, Chen Chu, Li Ruonan, Zhai Yuhong, Li Wenqiang, Wang Wei, Yang Jun, Huang Cuiyuan, Zhang Jing
Department of Cardiology, The First College of Clinical Medical Science, China Three Gorges University & Yichang Central People's Hospital, Yichang, China; Hubei Key Laboratory of Ischemic Cardiovascular Disease, Yichang, China; Hubei Provincial Clinical Research Center for Ischemic Cardiovascular Disease, Yichang, China.
Department of Cardiology, The First College of Clinical Medical Science, China Three Gorges University & Yichang Central People's Hospital, Yichang, China; Hubei Key Laboratory of Ischemic Cardiovascular Disease, Yichang, China; Hubei Provincial Clinical Research Center for Ischemic Cardiovascular Disease, Yichang, China; Central Laboratory, The First College of Clinical Medical Science, China Three Gorges University & Yichang Central People's Hospital, Yichang, China.
Biochim Biophys Acta Mol Basis Dis. 2025 Jun 21;1871(7):167959. doi: 10.1016/j.bbadis.2025.167959.
Inflammation and pyroptosis are pivotal in myocardial ischemia-reperfusion injury. Although leukocyte immunoglobulin-like receptor subfamily B4 (LILRB4) modulates inflammation in conditions such as myocardial hypertrophy, its involvement in myocardial ischemia-reperfusion injury (MIRI) remains ambiguous. Recombinant adenoviral vectors were designed to induce the overexpression or knockdown of LILRB4 in H9C2 cardiomyocytes or rat myocardial tissue. H9C2 cells were subjected to hypoxia for 2 h and reoxygenation for 4 h (H/R), while myocardial tissue experienced 30 min of ischemia followed by 2 h of reperfusion (I/R). Biochemical assay, histopathology, ELISA, and other tests were performed on myocardial cells and tissues. Meanwhile, LILRB4 knockout mice were used for further validation. LILRB4 promotes the release of inflammatory factors induced by I/R and H/R, thereby increasing the size of myocardial infarction and leading to functional impairment. Downregulation of LILRB4 suppressed SHP-2 phosphorylation and activation, consequently reducing the expression of the thioredoxin-interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), Caspase-1, and Gasdermin D (GSDMD). The SHP2 inhibitor PHPS1 mitigated the inflammatory and pyroptotic effects of LILRB4 in cardiomyocytes induced by H/R. Compared to wild-type mice, LILRB4 mice exhibited markedly diminished myocardial tissue swelling, decreased release of inflammatory cytokines, and a notable reduction in the expression of p-SHP2, TXNIP, NLRP3, Caspase-1, and GSDMD proteins after I/R induction.LILRB4 promotes inflammation and pyroptosis, which in turn worsens MIRI, likely through activating the TXNIP/NLRP3 signaling pathway, providing mechanistic insights into the MIRI.
炎症和细胞焦亡在心肌缺血再灌注损伤中起关键作用。尽管白细胞免疫球蛋白样受体B4（LILRB4）在心肌肥大等病症中调节炎症，但其在心肌缺血再灌注损伤（MIRI）中的作用仍不明确。设计重组腺病毒载体以诱导H9C2心肌细胞或大鼠心肌组织中LILRB4的过表达或敲低。H9C2细胞经历2小时缺氧和4小时复氧（H/R），而心肌组织经历30分钟缺血后再灌注2小时（I/R）。对心肌细胞和组织进行生化测定、组织病理学、ELISA和其他测试。同时，使用LILRB4基因敲除小鼠进行进一步验证。LILRB4促进I/R和H/R诱导的炎症因子释放，从而增加心肌梗死面积并导致功能障碍。LILRB4的下调抑制了SHP-2磷酸化和激活，从而降低了硫氧还蛋白相互作用蛋白（TXNIP）、NOD样受体蛋白3（NLRP3）、半胱天冬酶-1（Caspase-1）和Gasdermin D（GSDMD）的表达。SHP2抑制剂PHPS1减轻了H/R诱导的心肌细胞中LILRB4的炎症和细胞焦亡作用。与野生型小鼠相比，LILRB4基因敲除小鼠在I/R诱导后心肌组织肿胀明显减轻，炎症细胞因子释放减少，p-SHP2、TXNIP、NLRP3、Caspase-1和GSDMD蛋白表达显著降低。LILRB4促进炎症和细胞焦亡，进而使MIRI恶化，可能是通过激活TXNIP/NLRP3信号通路，为MIRI提供了机制性见解。
