1. Academic Validation
  2. Coronarin A modulated hepatic glycogen synthesis and gluconeogenesis via inhibiting mTORC1/S6K1 signaling and ameliorated glucose homeostasis of diabetic mice

Coronarin A modulated hepatic glycogen synthesis and gluconeogenesis via inhibiting mTORC1/S6K1 signaling and ameliorated glucose homeostasis of diabetic mice

  • Acta Pharmacol Sin. 2022 Sep 9. doi: 10.1038/s41401-022-00985-5.
Su-Ling Huang # 1 Wei Xie # 1 2 Yang-Liang Ye 1 Jia Liu 3 Hui Qu 1 Yu Shen 1 Ti-Fei Xu 1 Zhuo-Hui Zhao 1 2 Yu Shi 1 2 Jian-Hua Shen 4 Ying Leng 5 6
Affiliations

Affiliations

  • 1 State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
  • 2 University of Chinese Academy of Sciences, Beijing, 100049, China.
  • 3 Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
  • 4 State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China. jhshen@simm.ac.cn.
  • 5 State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China. yleng@simm.ac.cn.
  • 6 University of Chinese Academy of Sciences, Beijing, 100049, China. yleng@simm.ac.cn.
  • # Contributed equally.
Abstract

Promotion of hepatic glycogen synthesis and inhibition of hepatic glucose production are effective strategies for controlling hyperglycemia in type 2 diabetes mellitus (T2DM), but agents with both properties were limited. Herein we report coronarin A, a natural compound isolated from rhizomes of Hedychium gardnerianum, which simultaneously stimulates glycogen synthesis and suppresses gluconeogenesis in rat primary hepatocytes. We showed that coronarin A (3, 10 μM) dose-dependently stimulated glycogen synthesis accompanied by increased Akt and GSK3β phosphorylation in rat primary hepatocytes. Pretreatment with Akt Inhibitor MK-2206 (2 μM) or PI3K Inhibitor LY294002 (10 μM) blocked coronarin A-induced glycogen synthesis. Meanwhile, coronarin A (10 μM) significantly suppressed gluconeogenesis accompanied by increased phosphorylation of MEK, ERK1/2, β-catenin and increased the gene expression of TCF7L2 in rat primary hepatocytes. Pretreatment with β-catenin Inhibitor IWR-1-endo (10 μM) or ERK Inhibitor SCH772984 (1 μM) abolished the coronarin A-suppressed gluconeogenesis. More importantly, we revealed that coronarin A activated PI3K/Akt/GSK3β and ERK/Wnt/β-catenin signaling via regulation of a key upstream molecule IRS1. Coronarin A (10, 30 μM) decreased the phosphorylation of mTOR and S6K1, the downstream target of mTORC1, which further inhibited the serine phosphorylation of IRS1, and subsequently increased the tyrosine phosphorylation of IRS1. In type 2 diabetic ob/ob mice, chronic administration of coronarin A significantly reduced the non-fasting and fasting blood glucose levels and improved glucose tolerance, accompanied by the inhibited hepatic mTOR/S6K1 signaling and activated IRS1 along with enhanced PI3K/Akt/GSK3β and ERK/Wnt/β-catenin pathways. These results demonstrate the anti-hyperglycemic effect of coronarin A with a novel mechanism by inhibiting mTORC1/S6K1 to increase IRS1 activity, and highlighted coronarin A as a valuable lead compound for the treatment of T2DM.

Keywords

IRS1; coronarin A; gluconeogenesis; glycogen synthesis; mTORC1/S6K1 pathway; type 2 diabetes mellitus.

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