Category: signaling
β-cell insulin secretion + peripheral insulin action set systemic glucose disposal. Insulin → InsR (RTK) → IRS-1 → PI3K → AKT → GLUT4 translocation in muscle + adipose (peripheral glucose uptake) and inhibits hepatic gluconeogenesis. Incretin axis (GLP-1, GIP) augments glucose-dependent insulin release + delays gastric emptying + suppresses glucagon. Drug classes: insulin variants replace; GLP-1 agonists (semaglutide, tirzepatide dual GLP-1/GIP, liraglutide, dulaglutide, exenatide); DPP-4 inhibitors prolong endogenous GLP-1/GIP; SGLT2 inhibitors block renal glucose reabsorption; sulfonylureas / glinides close β-cell KATP channels for glucose-independent insulin release; TZDs (pioglitazone, rosiglitazone) activate PPAR-γ as insulin-sensitizers; metformin suppresses hepatic gluconeogenesis via AMPK + complex-I inhibition. Cross-links: gluconeogenesis, glycolysis, glycogen_metabolism, oxidative_phosphorylation.