Abstract：
Hederagenin (HDG), a medical herb, is known for its beneficial activities against diverse diseases. The cardioprotective effect of HDG has been preliminarily disclosed, but the efficacy and underlying mechanism by which HDG protects against myocardial ischemia-reperfusion (MI/R) injury have not been elucidated yet. To simulate MI/R injury, the left anterior descending artery was occluded for 30 min and then reperfusion for 120 min in a rat model, and the cellular model of hypoxia-reoxygenation (H/R) injury was constructed in H9c2 cardiomyocytes. Hematoxylin-eosin, Prussian blue, and 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining were conducted to assess the histological injury, iron deposition, and myocardial infarction. Myocardial enzymes and oxidative stress-related factors were detected using their commercial kits. Lipid peroxidation was measured using BODIPY581/591 probe, and iron content was detected. Cell counting kit (CCK)-8, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), and flow cytometry assays were performed to assess cell viability and apoptosis. Protein levels were investigated by western blot. The interaction between HDG and 5-lipoxygenase (ALOX5) was verified using molecular docking. Our findings indicated that HDG significantly attenuated myocardial dysfunction by reducing infarction and myocardial injury. HDG significantly attenuated myocardial apoptosis in vitro and in vivo, as well as alleviating oxidative stress via reducing reactive oxygen species (ROS) and maintaining the balance between antioxidant and oxidant enzymes. Meanwhile, HDG inhibited I/R-induced ferroptosis in myocardium and cardiomyocytes, including reducing lipid peroxidation and iron level. Moreover, the binding relationship between HDG and ALOX5 was verified, and HDG could concentration dependently downregulate ALOX5. Furthermore, ALOX5 overexpression eliminated the inhibition of HDG on H/R-induced apoptosis, oxidative stress, and ferroptosis in H9c2 cardiomyocytes. HDG ameliorated myocardial dysfunction and cardiomyocyte injury by reducing apoptosis, oxidative stress, and ferroptosis through inhibiting ALOX5, providing a new perspective on the prevention and treatment of MI/R injury.
摘要：
Hederagenin(HDG),一种药草，以其对各种疾病的有益活性而闻名。HDG的心脏保护作用已被初步披露，但HDG对心肌缺血再灌注(MI/R)损伤的保护作用和潜在机制尚未阐明。要模拟MI/R损伤，在大鼠模型中，将左前降支动脉闭塞30分钟，然后再灌注120分钟，建立了H9c2心肌细胞缺氧-复氧(H/R)损伤的细胞模型。苏木精-伊红,普鲁士蓝,和2,3,5-三苯基-2H-氯化四唑（TTC）染色以评估组织学损伤，铁沉积,和心肌梗塞。使用其商业试剂盒检测心肌酶和氧化应激相关因子。使用BODIPY581/591探针测量脂质过氧化,并检测到铁含量。细胞计数试剂盒（CCK）-8，末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（TUNEL），和流式细胞术测定进行评估细胞活力和凋亡。通过蛋白质印迹研究蛋白质水平。使用分子对接验证了HDG与5-脂氧合酶（ALOX5）之间的相互作用。我们的发现表明，HDG通过减少梗塞和心肌损伤来显着减轻心肌功能障碍。HDG在体外和体内显着减弱心肌细胞凋亡，以及通过减少活性氧（ROS）和维持抗氧化和氧化酶之间的平衡来减轻氧化应激。同时,HDG抑制I/R诱导的心肌和心肌细胞铁凋亡，包括减少脂质过氧化和铁水平。此外，验证了HDG与ALOX5的结合关系，HDG可以浓度依赖性地下调ALOX5。此外，ALOX5过表达消除了HDG对H/R诱导的细胞凋亡的抑制作用，氧化应激，H9c2心肌细胞的铁凋亡。HDG通过减少细胞凋亡改善心肌功能障碍和心肌细胞损伤，氧化应激，通过对ALOX5的抑制,为MI/R损伤的防治提供了新的视角。
