目的 探讨长梗冬青苷（pedunculoside，PE）对阿霉素（doxorubicin，DOX）诱导的心肌损伤的保护作用及机制。方法 体外采用DOX刺激AC16心肌细胞构建铁死亡模型，体内通过ip DOX诱导小鼠心肌损伤模型。给予PE或铁死亡抑制剂ferrostatin-1（Fer-1）干预后，采用MTT法检测细胞活力；流式细胞术检测细胞内活性氧（reactive oxygen species，ROS）水平；免疫荧光法检测细胞ROS、脂质过氧化物和Fe²⁺水平；分子对接检测PE与酰基辅酶A合成酶长链家族成员4（acyl-CoA synthetase long-chain family member 4，ACSL4）、前列腺素内过氧化物合酶2（prostaglandin-endoperoxide synthase 2，PTGS2）、膜铁转运蛋白1（ferroportin 1，FPN1）、铁蛋白重链1（ferritin heavy chain 1，FTH1）、铁蛋白（ferritin）的结合能力；试剂盒检测细胞和心脏组织内丙二醛（malonaldehyde，MDA）水平；Western blotting检测细胞和心脏组织内ACSL4、PTGS2、FPN1、ferritin、FTH1和铁蛋白轻链（ferritin light chain，FTL）的表达水平；超声心动仪检测小鼠心脏功能；血常规检测全血中中性粒细胞、淋巴细胞和红细胞的水平；苏木素-伊红（hematoxylin-eosin，HE）、Masson染色观察心脏组织的病理变化；qRT-PCR检测心脏组织中PTGS2、利钠肽B（natriuretic peptide B，Nppb）、白细胞介素-1β（interleukin-1β，IL-1β）的mRNA表达水平。结果 与模型组比较，PE能抑制DOX诱导的AC16细胞内ROS水平、脂质过氧化物和Fe²⁺水平的升高（P＜0.001），降低AC16细胞和心脏组织中MDA水平（P＜0.001）。分子对接结果显示，PE与ACSL4、PTGS2、FPN1、ferritin、FTH1蛋白有较稳定的结合能力。Western blotting结果显示，PE能抑制DOX诱导的AC16细胞和心脏组织中ACSL4、PTGS2蛋白表达的升高和FPN1、FTH1、FTL、ferritin蛋白表达的降低（P＜0.05、0.001）。此外，PE能够改善DOX诱导的心肌损伤模型小鼠的心功能（P＜0.01、0.001），抑制中性粒细胞百分比、中性粒细胞数量、红细胞数量的升高和淋巴细胞百分比的降低（P＜0.01、0.001），缓解心脏组织的病理损伤，下调PTGS2、Nppb、IL-1β的mRNA表达水平（P＜0.001），抑制心脏炎症反应。结论 PE能够改善DOX诱导的AC16细胞铁死亡，对DOX诱导的小鼠心肌损伤有保护作用，其机制可能是通过抑制铁死亡缓解心肌损伤。

Objective To investigate the cardioprotective effect and mechanism of pedunculoside (PE) on doxorubicin (DOX)-induced myocardial injury. Methods An ferroptosis model was constructed by stimulating AC16 cardiomyocytes with DOX in vitro, and a mouse myocardial injury model was induced by ip DOX in vivo. After intervention with PE or ferrostatin-1 (Fer-1), cell viability was detected using MTT assay; Flow cytometry was used to detect intracellular reactive oxygen species (ROS) level; Immunofluorescence assay was used to detect the levels of ROS, lipid peroxides, and Fe²⁺ in cells; Molecular docking was used to detect the binding ability of PE to acyl CoA synthase long chain family member 4 (ACSL4), prostaglandin endoperoxide synthase 2 (PTGS2), ferroportin 1 (FPN1), ferritin heavy chain 1 (FTH1) and ferritin; The reagent kit was used to detect the level of malondialdehyde (MDA) in cells and cardiac tissues; Western blotting was used to detect the expression levels of ACSL4, PTGS2, FPN1, ferritin, FTH1 and ferritin light chain (FTL) in cells and cardiac tissues; The cardiac function of mice was detected using echocardiography; Blood routine examination was used to detect the levels of neutrophils, lymphocytes and red blood cells in whole blood; Hematoxylin-eosin (HE) and Masson staining were used to observe the pathological changes in cardiac tissue; qRT-PCR was used to detect the mRNA expression levels of PTGS2, natriuretic peptide B (Nppb) and interleukin-1β (IL-1β) in cardiac tissue. Results Compared with model group, PE could inhibit the increase of ROS, lipid peroxides and Fe²⁺ levels induced by DOX in AC16 cells (P < 0.001), and reduce MDA level in AC16 cells and heart tissue (P < 0.001). The molecular docking results showed that PE had a relatively stable binding ability with ACSL4, PTGS2, FPN1, ferritin and FTH1 proteins. Western blotting results showed that PE could inhibit the increase in ACSL4 and PTGS2 protein expressions and the decrease in FPN1, FTH1, FTL and ferritin protein expressions induced by DOX in AC16 cells and heart tissue (P < 0.05, 0.001). In addition, PE could improve the cardiac function of DOX-induced myocardial injury model mice (P < 0.01, 0.001), inhibit the increase of neutrophil percentage, neutrophil count, red blood cell count, and decrease of lymphocyte percentage (P < 0.01, 0.001), alleviate pathological damage to cardiac tissue, down-regulate the mRNA expression levels of PTGS2, Nppb and IL-1β (P < 0.001), and inhibit cardiac inflammatory response. Conclusion PE could improve DOX-induced ferroptosis in AC16 cells and has a protective effect on DOX-induced myocardial injury in mice. Its mechanism may be to alleviate myocardial injury by inhibiting ferroptosis.

R285.5

“带土移植”人才引育计划（桂科AA23026010）；广西青年岐黄学者培育项目（GXQH202408）；中青年教师科研基础能力提升项目（2023JJB140603）