Hepcidin-25 peptide

Hepcidin, also known as LEAP-1 (liver-expressed antimicrobial peptide) or Hepcidin-25 is a hormone of 25 amino acids. Hepcidin is a cationic, cysteine-rich and tightly folded peptide stabilized by 4 disulfide bonds that plays a major role in innate immunity and iron homeostasis. Hepcidin inhibits iron transport by binding to the iron export channel ferroportin which is located on the basolateral surface of gut enterocytes and the plasma membrane of reticuloendothelial cells (macrophages). Hepcidin breaks down the transporter protein in the lysosome. Inhibiting ferroportin prevents iron exportation and iron is retained in cells. Hepcidin is regulated by iron through a complex of integral hemochromatosis proteins, like HFE, HJV and transferrin receptor 2. Hepcidin is also characterized by is antimicrobial activity in several vertebrate species, exerting its antimicrobial effect against both Gram-positive and Gram-negative bacteria as well as yeast, with for example an IC50 value against Saccharomyces cerevisae of 18 µM.