病毒性心肌炎患者心肌细胞中脂褐素的体电镜研究
陈泽崧，加苏尔·阿力甫，郭 帅，朱梦云，李海玲，刘伟静，祝 建，徐亚伟，车文良，刘 铮
（1. 南方科技大学冷冻电镜中心，深圳 广东 518055； 2. 同济大学附属第十人民医院心脏中心，上海 200072）
摘 要 脂褐素又称为“年龄色素”，是一种不可被溶酶体水解酶降解的黑色或褐色脂溶性物质。既往研究发现在炎症等病理情况下会加剧脂褐素的形成，并在心脏早衰症以及心肌肥大的患者心肌细胞中观察到了脂褐素的堆积。本研究首次在长新冠诱发心血管疾病患者的心肌活检组织中观察到大量堆积的脂褐素，并通过透射电子显微镜与离子束扫描电子显微镜对脂褐素进行了二维平面和三维立体结构上的观察和重构，为研究线粒体与脂褐素形成之间的联系提供一定的参考。
关键词 脂褐素；病毒性心肌炎；线粒体结构功能障碍；氧化应激；长新冠；体电镜
中图分类号：Q2-3；Q6-3；R36；R54；Q336 文献标识码：ADoi:10.3969/j.issn.1000-6281.2025.01.001
Structural characteristics of lipofuscin granules in cardiomyocytes from patients diagnosed with viral myocarditis patient investigated by volume electron microscopy
CHEN Zesong, JIASUER ALIFU, GUO Shuai, ZHU Mengyun, LI Hailing, LIU Weijing, ZHU Jian, XU Yawei, CHE Wenliang, LIU Zheng
（1. Cryo-Electron Microscopy Center , Southern University of Science and Technology , Shenzhen Guangdong 518055; 2. Department of Cardiology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China）
Abstract Lipofuscin, also known as “age pigment”, is a black or brown liposoluble substance resistant to degradation by lysosomal hydrolases. Previous studies have shown that inflammation can exacerbate the formation of lipofuscin, and significant accumulations of lipofuscin have been observed in the myocardial cells of patients with conditions such as premature heart failure and myocardial hypertrophy. In this study, we observed substantial accumulations of lipofuscin in the myocardial biopsy tissues from a patient with “Long COVID” associated cardiovascular disease. Using TEM (transmission electron microscopy) and FIB-SEM (focused ion beam scanning electron microscopy) we investigated the two-dimensional structure and three-dimensional reconstruction of lipofuscin, and provided valuable insights for exploring the connection between mitochondrial dysfunction and lipofuscin formation.
Keywords lipofuscin; cardiomyocytes; viral myocarditis; Long COVID; volume electron microscopy
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