Glucagon

 Glucagon is a 29-amino acid peptide hormone produced by alpha cells in the pancreas. It plays a critical role in glucose metabolism by counteracting the effects of insulin. Glucagon stimulates glycogenolysis and gluconeogenesis in the liver, increasing blood glucose levels during fasting or hypoglycemia. This hormone is essential for maintaining glucose homeostasis and ensuring a steady energy supply to the brain and other vital organs.

Research has highlighted glucagon's role in diabetes mellitus. In type 1 diabetes, impaired glucagon secretion contributes to hypoglycemia, while in type 2 diabetes, excessive glucagon action exacerbates hyperglycemia. Glucagon receptor antagonists are being investigated as a novel therapy for type 2 diabetes to reduce hepatic glucose production. Conversely, glucagon is used in emergency kits to treat severe hypoglycemia in diabetic patients.

Beyond glucose regulation, glucagon influences lipid metabolism and cardiovascular function. It promotes lipolysis and ketogenesis, providing alternative energy sources during prolonged fasting. Glucagon-like peptide-1 (GLP-1) analogs, which modulate glucagon signaling, are widely used to treat obesity and type 2 diabetes. These drugs enhance insulin secretion, suppress glucagon release, and promote weight loss.

Glucagon's role in energy balance and metabolism makes it a key player in metabolic disorders. Dysregulation of glucagon signaling is implicated in metabolic syndrome, non-alcoholic fatty liver disease (NAFLD), and cardiovascular diseases. Ongoing research aims to develop dual and triple agonists targeting glucagon, GLP-1, and other metabolic pathways to improve glycemic control and metabolic health.