Department of Internal Medicine, University of Ulsan College of Medicine, Seoul, Korea.
Department of Internal Medicine, Inje University Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea.
Diabetes Metab J. 2019 Jun;43(3):247-256. doi: 10.4093/dmj.2018.0221. Epub 2019 Mar 27.
Adipose tissue inflammation is considered a major contributing factor in the development of obesity-associated insulin resistance and cardiovascular diseases. However, the cause of adipose tissue inflammation is presently unclear. The role of mitochondria in white adipocytes has long been neglected because of their low abundance. However, recent evidence suggests that mitochondria are essential for maintaining metabolic homeostasis in white adipocytes. In a series of recent studies, we found that mitochondrial function in white adipocytes is essential to the synthesis of adiponectin, which is the most abundant adipokine synthesized from adipocytes, with many favorable effects on metabolism, including improvement of insulin sensitivity and reduction of atherosclerotic processes and systemic inflammation. From these results, we propose a new hypothesis that mitochondrial dysfunction in adipocytes is a primary cause of adipose tissue inflammation and compared this hypothesis with a prevailing concept that "adipose tissue hypoxia" may underlie adipose tissue dysfunction in obesity. Recent studies have emphasized the role of the mitochondrial quality control mechanism in maintaining mitochondrial function. Future studies are warranted to test whether an inadequate mitochondrial quality control mechanism is responsible for mitochondrial dysfunction in adipocytes and adipose tissue inflammation.
脂肪组织炎症被认为是肥胖相关胰岛素抵抗和心血管疾病发展的主要因素。然而，目前尚不清楚脂肪组织炎症的原因。由于线粒体含量低，其在白色脂肪细胞中的作用长期以来一直被忽视。然而，最近的证据表明，线粒体对于维持白色脂肪细胞的代谢稳态至关重要。在一系列最近的研究中，我们发现白色脂肪细胞中线粒体的功能对于脂联素的合成是必不可少的，脂联素是脂肪细胞合成的最丰富的脂肪因子，对代谢有许多有益的影响，包括改善胰岛素敏感性和减少动脉粥样硬化过程和全身炎症。根据这些结果，我们提出了一个新的假设，即脂肪细胞中线粒体功能障碍是脂肪组织炎症的主要原因，并将这一假设与目前流行的概念“脂肪组织缺氧”可能是肥胖相关脂肪组织功能障碍的基础进行了比较。最近的研究强调了线粒体质量控制机制在维持线粒体功能中的作用。未来的研究需要验证线粒体质量控制机制是否不足以导致脂肪细胞和脂肪组织炎症中的线粒体功能障碍。
