OVERVIEW OF GLP-1 AND ITS PHYSIOLOGY

Diabetes mellitus is most prevailing and pervasive metabolic disorder across the globe, out of all these, cases 90% are suffering from diabetes mellitus type 2. Two peptide hormones basically released from the enteroendocrine cells, K-cells present in duodenum release Glucose Dependent Insulinotropic Polypeptide (GIP) and L-cells present in pancreas, ileum and colon release Glucagon Like Peptide-1 (GLP-1), both GIP and GLP-1 are enzymatically fragmented by Dipeptide Pepidase-4 (DPP-4).Monosaccharides get absorbed by the intestinal cells through membrane transporter Sodium Glucose Co-transporter-1 (SGLT-1) which further promotes liberation of GLP-1 from intestinal L-cells.Many investigations have revealed that high protein diet releases more amount of GLP-1 in contrast with the normal calorie diet.Incretin effect leads to release of insulin by the GLP-1, and GLP-1 gets released by the oral ingestion of nutrients.Together, glucose and GLP-1 close the Potassium-ATP channel.It was searched that the potassium-ATP channel was phosphorylated by GLP-1-induced PKA activation, contributing to its closure.GLP-1 also reduces blood sugar by preventing glucagon secretion.According to preclinical research examining the mechanism by which GLP-1 receptor agonists cause weight loss, the primary mechanism is a decrease in food intake without modifications in activity level or energy expenditure.