uroguanylin

Uroguanylin is a 16-amino acid peptide hormone primarily secreted by enterochromaffin cells in the duodenum and proximal small intestine. It is encoded by the GUCA2B gene in humans. Uroguanylin acts as an endogenous agonist of the transmembrane receptor guanylyl cyclase 2C (GUCY2C), also known as GC-C, on intestinal epithelial cells and other tissues. Upon binding to GUCY2C, it increases intracellular cyclic guanosine monophosphate (cGMP) levels, leading to enhanced secretion of chloride and bicarbonate ions into the intestinal lumen and inhibition of sodium absorption. This mechanism regulates electrolyte and water transport in both intestinal and renal epithelia[8][9][4]. Uroguanylin also functions as a natriuretic factor that promotes renal sodium excretion when dietary salt intake is high[1][3][5]. Beyond its role in fluid balance, recent research suggests that uroguanylin modulates energy homeostasis by acting on hypothalamic GUCY2C receptors to reduce food intake, increase energy expenditure via sympathetic nervous system activation, induce satiety after meals, promote brown adipose tissue thermogenesis, and contribute to body weight regulation[6][2]. Dysregulation or deficiency of uroguanylin has been implicated in hypertension due to impaired sodium excretion responses[1], obesity due to altered appetite signaling[6][2], heart failure, gastrointestinal diseases such as diarrhea (via related bacterial toxins), and possibly glucose intolerance.

Other names

guanylate cyclase activator 2BUGN