CAS Key Laboratory of Nutrition, Metabolism, and Food Safety, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.
China Animal Health and Epidemiology Center, Qingdao, Shangdong, 266032, China.
Mol Metab. 2021 May;47:101182. doi: 10.1016/j.molmet.2021.101182. Epub 2021 Feb 5.
Fat storage and mobilization in adipose tissue play a central role in energy metabolism and are directly linked to the development of obesity. Upon starvation, fat is mobilized from adipose tissue by lipolysis, a process by which triglycerides are hydrolyzed to free fatty acids to be used as an energy source in skeletal muscles and other tissues. However, how lipolysis is activated by starvation is not fully known. In this study, we demonstrate that PAQR11, a member of the progesterone and AdipoQ receptor family, regulates starvation-mediated lipolysis. Paqr11-deleted mice are resistant to high-fat diet-induced obesity. Paqr11 deletion promotes lipolysis in white adipose tissue, characterized by increased phosphorylations of hormone-sensitive lipase (HSL) and perilipin 1 (PLIN1) and elevated serum levels of glycerol and free fatty acids. PKA activity and cAMP levels in white adipose tissue are also increased by Paqr11 deletion, accompanied by accelerated protein degradation of phosphodiesterase 4D (PDE4D). Mechanistically, PAQR11 decreases the interaction of PDE4D with SKP1-CUL1-FBXO2 E3 ligase complex, thus modulating the polyubiquitination/degradation of PDE4D. Fasting decreases the expression of the Paqr11 gene, and starvation-induced lipolysis in white adipose tissue is enhanced by Paqr11 deletion, while insulin-mediated suppression of lipolysis is not affected. Collectively, these results reveal that PAQR11 regulates lipolysis of adipose tissue and affects high-fat diet-induced obesity.
脂肪在脂肪组织中的储存和动员在能量代谢中起着核心作用,并且与肥胖的发展直接相关。在饥饿时,脂肪通过脂肪分解从脂肪组织中动员出来,这是一个将甘油三酯水解为游离脂肪酸的过程,以供骨骼肌和其他组织用作能源。然而,脂肪分解是如何被饥饿激活的还不完全清楚。在这项研究中,我们证明了孕激素和脂联素受体家族的成员 PAQR11 调节饥饿介导的脂肪分解。缺失 Paqr11 的小鼠对高脂肪饮食诱导的肥胖具有抗性。Paqr11 的缺失促进了白色脂肪组织中的脂肪分解,其特征是激素敏感脂肪酶 (HSL) 和 perilipin 1 (PLIN1) 的磷酸化增加,以及血清甘油和游离脂肪酸水平升高。白色脂肪组织中的 PKA 活性和 cAMP 水平也因 Paqr11 的缺失而增加,同时伴随着磷酸二酯酶 4D (PDE4D) 的蛋白降解加速。在机制上,PAQR11 降低了 PDE4D 与 SKP1-CUL1-FBXO2 E3 连接酶复合物的相互作用,从而调节了 PDE4D 的多泛素化/降解。禁食会降低 Paqr11 基因的表达,而白色脂肪组织中的饥饿诱导脂肪分解会因 Paqr11 的缺失而增强,而胰岛素介导的脂肪分解抑制不受影响。总的来说,这些结果表明 PAQR11 调节脂肪组织的脂肪分解,并影响高脂肪饮食诱导的肥胖。