Molecular Recognition Section and.
Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA.
JCI Insight. 2021 May 24;6(10):146577. doi: 10.1172/jci.insight.146577.
Obesity is the major driver of the worldwide epidemic in type 2 diabetes (T2D). In the obese state, chronically elevated plasma free fatty acid levels contribute to peripheral insulin resistance, which can ultimately lead to the development of T2D. For this reason, drugs that are able to regulate lipolytic processes in adipocytes are predicted to have considerable therapeutic potential. Gi-coupled P2Y14 receptor (P2Y14R; endogenous agonist, UDP-glucose) is abundantly expressed in both mouse and human adipocytes. Because activated Gi-type G proteins exert an antilipolytic effect, we explored the potential physiological relevance of adipocyte P2Y14Rs in regulating lipid and glucose homeostasis. Metabolic studies indicate that the lack of adipocyte P2Y14R enhanced lipolysis only in the fasting state, decreased body weight, and improved glucose tolerance and insulin sensitivity. Mechanistic studies suggested that adipocyte P2Y14R inhibits lipolysis by reducing lipolytic enzyme activity, including ATGL and HSL. In agreement with these findings, agonist treatment of control mice with a P2Y14R agonist decreased lipolysis, an effect that was sensitive to inhibition by a P2Y14R antagonist. In conclusion, we demonstrate that adipose P2Y14Rs were critical regulators of whole-body glucose and lipid homeostasis, suggesting that P2Y14R antagonists might be beneficial for the therapy of obesity and T2D.
肥胖是全球 2 型糖尿病(T2D)流行的主要驱动因素。在肥胖状态下,慢性升高的血浆游离脂肪酸水平导致外周胰岛素抵抗,最终导致 T2D 的发生。出于这个原因,能够调节脂肪细胞脂肪分解过程的药物预计具有相当大的治疗潜力。Gi 偶联的 P2Y14 受体(P2Y14R;内源性激动剂,UDP-葡萄糖)在小鼠和人类脂肪细胞中均大量表达。由于激活的 Gi 型 G 蛋白发挥抗脂肪分解作用,我们探讨了脂肪细胞 P2Y14R 在调节脂质和葡萄糖稳态中的潜在生理相关性。代谢研究表明,脂肪细胞 P2Y14R 的缺失仅在禁食状态下增强脂肪分解,降低体重,并改善葡萄糖耐量和胰岛素敏感性。机制研究表明,脂肪细胞 P2Y14R 通过降低脂肪分解酶活性(包括 ATGL 和 HSL)来抑制脂肪分解。与这些发现一致的是,用 P2Y14R 激动剂处理对照小鼠可降低脂肪分解,该作用对 P2Y14R 拮抗剂敏感。总之,我们证明了脂肪组织 P2Y14R 是全身葡萄糖和脂质稳态的关键调节剂,提示 P2Y14R 拮抗剂可能有益于肥胖和 T2D 的治疗。