Acetaldehyde dehydrogenase (ALDH (or more specifically, ALDH1A1, ALDH2, or ALDH1B1 depending on isoform))

Acetaldehyde dehydrogenase is an enzyme responsible for catalyzing the conversion of acetaldehyde into acetyl-CoA, a critical step in the metabolism and detoxification of ethanol-derived and endogenous aldehydes. The reaction it catalyzes is: Acetaldehyde + NAD⁺ + Coenzyme A ↔ Acetyl-CoA + NADH + H⁺ In humans, this function is primarily carried out by three genes—ALDH1A1, ALDH2, and ALDH1B1—which encode different isoforms located in various cellular compartments. The mitochondrial form (ALDH2) plays a particularly important role in metabolizing toxic acetaldehyde produced during ethanol breakdown. Dysfunction or genetic variation in these enzymes—most notably the common East Asian variant ALDH2*2—can lead to increased risk for several diseases including cancer and cardiovascular conditions due to impaired detoxification capacity. Pharmacologically, inhibitors like disulfiram exploit this pathway therapeutically by blocking the enzyme's activity as part of treatment programs for alcoholism[1][3][4].

Other names

Aldehyde dehydrogenaseALDHMitochondrial aldehyde dehydrogenase (for ALDH2)Cytosolic aldehyde dehydrogenase (for ALDH1A1)

Inhibition of acetaldehyde dehydrogenase leads to accumulation of acetaldehyde after alcohol consumption, causing unpleasant effects that deter drinking.