State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.
National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences , Beijing , China.
Autophagy. 2019 Nov;15(11):1882-1898. doi: 10.1080/15548627.2019.1596482. Epub 2019 Apr 6.
There is overwhelming evidence for an association between impaired mitochondrial function and metabolic syndrome. Mitophagy, a process that selectively removes damaged mitochondria a specialized form of autophagy, is essential for mitochondrial quality control (mitochondrial QC) and metabolic homeostasis. We thus addressed the potential role of defective mitophagy in the pathogenesis of metabolic disorders. Mice lacking , a newly characterized mitophagy receptor, develop more severe obesity and insulin resistance when fed a high-fat diet (HFD). Ablation of results in defective mitophagy and impaired mitochondrial QC and in white adipose tissue (WAT). In addition, there is more pronounced WAT remodeling with more adipose tissue-associated macrophages infiltration, more M1 macrophage polarization and thus an elevated inflammatory response. Mechanistically, hyperactivation of MAPK/JNK leads to insulin insensitivity, which can be inhibited by knocking out / in KO mice. Our results demonstrate that dysregulated mitochondrial QC due to defective mitophagy receptor FUNDC1 links with metabolic disorders MAPK signaling and inflammatory responses. : ATMs: adipose tissue macrophages; BAT: brown adipose tissue; BMDMs: bone marrow-derived macrophages; GOT1/AST: glutamic-oxaloacetic transaminase 1, soluble; GPT/ALT: glutamic pyruvic transaminase, soluble; H&E staining: hematoxylin and eosin staining; HFD: high-fat diet; LIR: LC3-interacting region; mitochondrial QC: mitochondrial quality control; mito-ROS: mitochondrial ROS; mtDNA: mitochondrial DNA; RT-PCR: real-time-PCR; T2D: type 2 diabetes; WAT: white adipose tissue.
有大量证据表明,线粒体功能障碍与代谢综合征之间存在关联。自噬是一种选择性清除受损线粒体的过程,是一种特殊形式的自噬,对于线粒体质量控制(线粒体 QC)和代谢稳态至关重要。因此,我们研究了自噬缺陷在代谢紊乱发病机制中的潜在作用。缺乏一种新鉴定的自噬受体 的小鼠在高脂肪饮食(HFD)喂养时会发展出更严重的肥胖和胰岛素抵抗。 缺失导致自噬缺陷和线粒体 QC 受损,并在白色脂肪组织(WAT)中。此外,WAT 重塑更为明显,脂肪组织相关巨噬细胞浸润更多,M1 巨噬细胞极化更为明显,炎症反应更为强烈。从机制上讲,MAPK/JNK 的过度激活导致胰岛素不敏感,而敲除 / 敲入 (KO)小鼠可以抑制这种不敏感。我们的研究结果表明,由于自噬受体 FUNDC1 的缺陷导致的线粒体 QC 失调与代谢紊乱、MAPK 信号和炎症反应有关。