Alda-1

Ethanol is metabolized to acetaldehyde in people, which is then metabolized to acetic acid primarily by ALDH2.^[1] People have various ALDH2 alleles. ALDH2*1 is a common allele (wild type), but about 40% of people of East Asian ethnicity have one or two copies of the dominant ALDH2*2 instead, which causes ALDH2 deficiency. If deficient people drink ethanol, they suffer from alcohol flush reaction due to acetaldehyde accumulation.^[3]

Four Alda-1 molecules bind to each monomer of ALDH2 tetramer. This enhances NAD⁺ binding to ALDH2. NAD⁺ is required by ALDH2 for its enzymatic activity,^[4] which is why Alda-1 increases ALDH2 activity by 2.1 fold if ALDH2 is coded by ALDH2*1 and by 11 fold if it is coded ALDH2*2.^[2]

Chen et al. first reported Alda-1 in 2008.^[2][1] Alda-1 is the first known aldehyde dehydrogenase activator.^[3]