目的 探討長梗冬青苷（pedunculoside，PE）對阿霉素（doxorubicin，DOX）誘導的心肌損傷的保護作用及機制。方法 體外采用DOX刺激AC16心肌細胞構(gòu)建鐵死亡模型，體內(nèi)通過ip DOX誘導小鼠心肌損傷模型。給予PE或鐵死亡抑制劑ferrostatin-1（Fer-1）干預后，采用MTT法檢測細胞活力；流式細胞術(shù)檢測細胞內(nèi)活性氧（reactive oxygen species，ROS）水平；免疫熒光法檢測細胞ROS、脂質(zhì)過氧化物和Fe²⁺水平；分子對接檢測PE與酰基輔酶A合成酶長鏈家族成員4（acyl-CoA synthetase long-chain family member 4，ACSL4）、前列腺素內(nèi)過氧化物合酶2（prostaglandin-endoperoxide synthase 2，PTGS2）、膜鐵轉(zhuǎn)運蛋白1（ferroportin 1，F(xiàn)PN1）、鐵蛋白重鏈1（ferritin heavy chain 1，F(xiàn)TH1）、鐵蛋白（ferritin）的結(jié)合能力；試劑盒檢測細胞和心臟組織內(nèi)丙二醛（malonaldehyde，MDA）水平；Western blotting檢測細胞和心臟組織內(nèi)ACSL4、PTGS2、FPN1、ferritin、FTH1和鐵蛋白輕鏈（ferritin light chain，F(xiàn)TL）的表達水平；超聲心動儀檢測小鼠心臟功能；血常規(guī)檢測全血中中性粒細胞、淋巴細胞和紅細胞的水平；蘇木素-伊紅（hematoxylin-eosin，HE）、Masson染色觀察心臟組織的病理變化；qRT-PCR檢測心臟組織中PTGS2、利鈉肽B（natriuretic peptide B，Nppb）、白細胞介素-1β（interleukin-1β，IL-1β）的mRNA表達水平。結(jié)果 與模型組比較，PE能抑制DOX誘導的AC16細胞內(nèi)ROS水平、脂質(zhì)過氧化物和Fe²⁺水平的升高（P＜0.001），降低AC16細胞和心臟組織中MDA水平（P＜0.001）。分子對接結(jié)果顯示，PE與ACSL4、PTGS2、FPN1、ferritin、FTH1蛋白有較穩(wěn)定的結(jié)合能力。Western blotting結(jié)果顯示，PE能抑制DOX誘導的AC16細胞和心臟組織中ACSL4、PTGS2蛋白表達的升高和FPN1、FTH1、FTL、ferritin蛋白表達的降低（P＜0.05、0.001）。此外，PE能夠改善DOX誘導的心肌損傷模型小鼠的心功能（P＜0.01、0.001），抑制中性粒細胞百分比、中性粒細胞數(shù)量、紅細胞數(shù)量的升高和淋巴細胞百分比的降低（P＜0.01、0.001），緩解心臟組織的病理損傷，下調(diào)PTGS2、Nppb、IL-1β的mRNA表達水平（P＜0.001），抑制心臟炎癥反應(yīng)。結(jié)論 PE能夠改善DOX誘導的AC16細胞鐵死亡，對DOX誘導的小鼠心肌損傷有保護作用，其機制可能是通過抑制鐵死亡緩解心肌損傷。

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

“帶土移植”人才引育計劃（桂科AA23026010）；廣西青年岐黃學者培育項目（GXQH202408）；中青年教師科研基礎(chǔ)能力提升項目（2023JJB140603）