Acetaldehyde Dehydrogenases in Liver Zonation and Liver Cancer

Abstract

ALDHs consist of 24 families in the eukaryotic ALDH gene superfamily. Nineteen of them are found in the human genome and belong to the ALDH1-9, ALDH16, and ALDH18 families. 1 There are six isotype genes in the ALDH1 family (ALDH1A1, ALDH1A2, ALDH1A3, ALDH1B1, ALDH1L1, and ALDH1L2). Among them, ALDH1A1, ALDH1A2, and ALDH1A3 encode cytosolic enzymes that oxidize retinal and aliphatic aldehydes. ALDH1A1 protein binds to retinaldehyde in great affinity and has been considered a major retinoid acid-metabolizing enzyme. 2 Cytosolic ALDH1A1 also plays a role in acetaldehyde oxidation and alcohol preference