Fig. 1: Role of arginase metabolism in regulating polyamine and NO production.
From: Arginase: shedding light on the mechanisms and opportunities in cardiovascular diseases
Arginase converts L-arginine to urea and L-ornithine that is further metabolized by ODC to polyamines including putrescine, spermidine, and spermine, which play a significant role in cell proliferation from cardiovascular system, or is converted by OAT to L-proline that is essential for collagen formation. Meanwhile, L-arginine also serves as substrate of the enzyme NOS which specifically catalyzes L-arginine to L-citrulline and NO which can promote vasorelaxation and myocardial contractility. The increase of arginase may cause NOS-uncoupling, which contributes to decreased NO production and increased O2− and ONOO−. ODC ornithine decarboxylase, OAT ornithine aminotransferase, NOS nitric oxide synthase, O2− superoxide anion, NO nitric oxide, ONOO− peroxynitrite.
