Division of Cardiology, Department of Medicine, University of California, Los Angeles, CA, 90095, USA.
Division of Dermatology, Department of Medicine, University of California, Los Angeles, CA, 90095, USA.
Nat Commun. 2022 Nov 4;13(1):6661. doi: 10.1038/s41467-022-34468-2.
Parkin, an E3 ubiquitin ligase, plays an essential role in mitochondrial quality control. However, the mechanisms by which Parkin connects mitochondrial homeostasis with cellular metabolism in adipose tissue remain unclear. Here, we demonstrate that Park2 gene (encodes Parkin) deletion specifically from adipose tissue protects mice against high-fat diet and aging-induced obesity. Despite a mild reduction in mitophagy, mitochondrial DNA content and mitochondrial function are increased in Park2 deficient white adipocytes. Moreover, Park2 gene deletion elevates mitochondrial biogenesis by increasing Pgc1α protein stability through mitochondrial superoxide-activated NAD(P)H quinone dehydrogenase 1 (Nqo1). Both in vitro and in vivo studies show that Nqo1 overexpression elevates Pgc1α protein level and mitochondrial DNA content and enhances mitochondrial activity in mouse and human adipocytes. Taken together, our findings indicate that Parkin regulates mitochondrial homeostasis by balancing mitophagy and Pgc1α-mediated mitochondrial biogenesis in white adipocytes, suggesting a potential therapeutic target in adipocytes to combat obesity and obesity-associated disorders.
Parkin 是一种 E3 泛素连接酶,在维持线粒体质量中发挥重要作用。然而,Parkin 如何将线粒体稳态与脂肪组织中的细胞代谢联系起来的机制尚不清楚。在这里,我们证明 Park2 基因(编码 Parkin)在脂肪组织中的特异性缺失可保护小鼠免受高脂肪饮食和衰老引起的肥胖。尽管自噬作用略有减少,但 Park2 缺陷的白色脂肪细胞中线粒体 DNA 含量和线粒体功能增加。此外,Park2 基因缺失通过增加 Pgc1α 蛋白稳定性(通过线粒体超氧化物激活的 NAD(P)H 醌氧化还原酶 1(Nqo1))来增加线粒体生物发生。体外和体内研究均表明,Nqo1 的过表达可提高 Pgc1α 蛋白水平和线粒体 DNA 含量,并增强小鼠和人脂肪细胞中的线粒体活性。总之,我们的研究结果表明,Parkin 通过平衡白色脂肪细胞中的自噬和 Pgc1α 介导的线粒体生物发生来调节线粒体稳态,为对抗肥胖症和肥胖相关疾病提供了脂肪细胞中潜在的治疗靶点。