Amine oxidase [copper-containing] (AOC)

Amine oxidase [copper-containing] (AOC) refers to a family of enzymes, including AOC1 (diamine oxidase), AOC2 (retina-specific amine oxidase), and AOC3 (vascular adhesion protein-1), that utilize copper and a topaquinone cofactor to catalyze the oxidative deamination of primary amines [1, 6]. AOC3, also known as VAP-1 or SSAO, is a prominent therapeutic target due to its dual function as an enzyme and an adhesion molecule that facilitates leukocyte trafficking to inflamed tissues [4, 14]. AOC1 plays a vital role in the degradation of extracellular histamine, and its deficiency is the primary cause of histamine intolerance [7, 10]. Therapeutic strategies targeting this family primarily focus on AOC3 inhibitors for treating chronic inflammatory diseases, fibrosis (such as NASH), and diabetic complications [17, 18]. A significant challenge in drug development is achieving high selectivity for AOC3 over AOC1 to avoid adverse effects related to impaired histamine metabolism [1, 3]. Additionally, the generation of reactive byproducts like hydrogen peroxide and aldehydes by these enzymes contributes to oxidative stress and tissue damage in various pathologies [8, 16].

Other names

Copper amine oxidaseCAOSemicarbazide-sensitive amine oxidaseSSAOVascular adhesion protein-1VAP-1Diamine oxidaseDAOHistaminaseAmine oxidase [copper-containing] 1Amine oxidase [copper-containing] 2Amine oxidase [copper-containing] 3

Inhibition of the enzymatic activity of copper-containing amine oxidases, which prevents the oxidative deamination of primary amines and reduces the production of pro-inflammatory and cytotoxic byproducts such as hydrogen peroxide, aldehydes, and ammonia; in the case of AOC3, this also inhibits leukocyte recruitment and extravasation to sites of inflammation [14, 18].