Qin Xing, Fei Juanjuan, Duan Yu, Ceylan Asli F, Zhang Fuyang, Ren Jun
Department of Cardiology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, Shaanxi, China.
Department of Cardiology and Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital Fudan University, Shanghai, 200032, China.
Cell Regen. 2022 Jun 2;11(1):21. doi: 10.1186/s13619-022-00121-y.
Mesenchymal stem cells (MSCs)-based therapy has displayed some promises in ischemia heart diseases although its efficacy may be affected by changes in surrounding environments. This study evaluated the role of autophagy insufficiency using Beclin1 haploinsufficiency (BECN) on intra-myocardial MSC transplantation-evoked effect against myocardial infarction. Donor MSCs from C57BL/6 mice were labelled with cell-tracker CM Dil and were delivered into LV free wall adjacent to infarct region in wild-type (WT) and BECN recipient mice following ligation of left main coronary artery (MI-MSCs). Ten days following MI, myocardial function was assessed using echocardiography. Cardiomyocyte contractility and intracellular Ca were monitored using cardiomyocytes from the area-at-risk adjacent to infarct. CM-Dil labeled cells were tracked in MSCs recipient mice using fluorescence microscopy. Lectin, Masson trichrome staining and Western blot analysis were employed to determine cardiomyocyte area, scar fibrosis, apoptosis and inflammation. MI insult triggered scar fibrosis, LV chamber dilation, decreased fractional shortening, ejection fraction, cardiomyocyte shortening, maximal velocity of shortening and relengthening as well as prolonged relengthening, which were abrogated or attenuated by MSCs therapy in WT but not BECN mice. MI decreased intracellular Ca rise and decay in response to electrical stimuli without affecting resting intracellular Ca, which were reconciled by MSCs in WT but not BECN mice. MSCs further attenuated MI-induced mitochondrial ultrastructural injury, apoptosis, inflammation and autophagy defects in peri-infarct area in WT but not BECN mice. Collectively, our results suggested that autophagy insufficiency dampened in MSCs-elicited cardioprotection associated with dampened apoptosis and inflammation.
基于间充质干细胞（MSCs）的治疗在缺血性心脏病中已显示出一些前景，尽管其疗效可能会受到周围环境变化的影响。本研究利用Beclin1单倍体不足（BECN）评估自噬不足在心肌内MSCs移植诱发的抗心肌梗死效应中的作用。将来自C57BL/6小鼠的供体MSCs用细胞追踪染料CM Dil标记，并在野生型（WT）和BECN受体小鼠左冠状动脉结扎后（MI-MSCs），将其注射到梗死区域附近的左心室游离壁。心肌梗死后10天，使用超声心动图评估心脏功能。使用梗死附近危险区域的心肌细胞监测心肌细胞收缩力和细胞内钙。使用荧光显微镜在MSCs受体小鼠中追踪CM-Dil标记的细胞。采用凝集素、Masson三色染色和蛋白质印迹分析来确定心肌细胞面积、瘢痕纤维化、凋亡和炎症。心肌梗死损伤引发瘢痕纤维化、左心室腔扩张、缩短分数、射血分数、心肌细胞缩短、最大缩短速度和再延长速度降低以及再延长时间延长，这些在WT小鼠中被MSCs治疗所消除或减轻，但在BECN小鼠中没有。心肌梗死降低了电刺激后细胞内钙的升高和衰减，而不影响静息细胞内钙，这在WT小鼠中被MSCs纠正，但在BECN小鼠中没有。MSCs进一步减轻了WT小鼠而非BECN小鼠梗死周围区域MI诱导的线粒体超微结构损伤、凋亡、炎症和自噬缺陷。总的来说，我们的结果表明自噬不足减弱了MSCs引发的与凋亡和炎症减轻相关的心脏保护作用。
