Glucagon drives hepatic gluconeogenesis and maintains blood glucose levels during fasting. The mechanism that attenuates glucagon action following refeeding is not understood. The present study demonstrates an increase in perivenous liver hypoxia immediately after feeding, which stabilizes hypoxia-inducible factor 2α (HIF2α) in liver. The transient postprandial increase in hepatic HIF2α attenuates glucagon signaling. Hepatocyte-specific disruption of HIF2α increases postprandial blood glucose and potentiates the glucagon response. Independent of insulin/AKT signaling, activation of hepatic HIF2α resulted in lower blood glucose, improved glucose tolerance, and decreased gluconeogenesis due to blunted hepatic glucagon action. Mechanistically, HIF2α abrogated glucagon-PKA signaling by activating cAMP-phosphodiesterases in a MEK/ERK-dependent manner. Repression of glucagon signaling by HIF2α ameliorated hyperglycemia in streptozotocin-induced diabetes and acute insulin-resistant animal models. This study reveals that HIF2α is essential for the acute postprandial regulation of hepatic glucagon signaling and suggests HIF2α as a potential therapeutic target in the treatment of diabetes.
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http://dx.doi.org/10.1016/j.cmet.2016.01.004 | DOI Listing |
The immune system shapes body metabolism, while interactions between peripheral neurons and immune cells control tissue homeostasis and immunity. However, whether peripheral neuroimmune interactions orchestrate endocrine system functions remains unexplored. After fasting, mice lacking type 2 innate lymphoid cells (ILC2s) displayed disrupted glucose homeostasis, impaired pancreatic glucagon secretion, and inefficient hepatic gluconeogenesis.
View Article and Find Full Text PDFAntioxid Redox Signal
January 2025
Department of Pharmacology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prevalent hepatic disorder worldwide. Arachidonic acid 15-lipoxygenase (ALOX15), an enzyme catalyzing the peroxidation of polyunsaturated fatty acids, plays a crucial role in various diseases. Here, we sought to investigate the involvement of ALOX15 in MASLD.
View Article and Find Full Text PDFCell Rep
January 2025
Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China; Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China; Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, China. Electronic address:
Glucagon has recently been found to modulate liver fat content, in addition to its role in regulating gluconeogenesis. However, the precise mechanisms by which glucagon signaling synchronizes glucose and lipid metabolism in the liver remain poorly understood. By employing chemical and genetic approaches, we demonstrate that inhibiting the androgen receptor (AR) impairs the ability of glucagon to stimulate gluconeogenesis and lipid catabolism in primary hepatocytes and female mice.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
Department of Endocrinology, Second Hospital of Shanxi Medical University, Taiyuan 030000, China. Electronic address:
Tirzepatide is a dual agonist of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors and is a promising therapeutic option for type 2 diabetes mellitus (T2DM). Nevertheless, its effect and underlying mechanism on hepatic steatosis remain ambiguous. Herein, we explored the impact of tirzepatide on improving hepatic steatosis in diabetic mice, with a particular focus on the gut microbiota and bile acids (BAs) using animal models.
View Article and Find Full Text PDFGut Microbes
December 2025
School of Pharmacy, Jiangxi Medical College, Nanchang University, Nanchang, China.
Diabetes mellitus (DM) is a complex metabolic disease characterized by hyperglycemia. Recently, the incidence of diabetes has increased exponentially, and it is estimated to become the seventh leading cause of global mortality by 2030. Glucagon-like peptide-1 (GLP-1), a hormone derived from the intestine, has been demonstrated to exert remarkable hypoglycemic effects.
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