daidzein and Alcoholism

The ALDH2*2 gene encoding the inactive variant form of mitochondrial aldehyde dehydrogenase (ALDH2) protects nearly all carriers of this gene from alcoholism. Inhibition of ALDH2 has hence become a possible strategy to treat alcoholism. The natural product 7-O-glucosyl-4'-hydroxyisoflavone (daidzin), isolated from the kudzu vine ( Peruraria lobata), is a specific inhibitor of ALDH2 and suppresses ethanol consumption. Daidzin is the active principle in a herbal remedy for "alcohol addiction" and provides a lead for the design of improved ALDH2. The structure of daidzin/ALDH2 in complex at 2.4 A resolution shows the isoflavone moiety of daidzin binding close to the aldehyde substrate-binding site in a hydrophobic cleft and the glucosyl function binding to a hydrophobic patch immediately outside the isoflavone-binding pocket. These observations provide an explanation for both the specificity and affinity of daidzin (IC50 =80 nM) and the affinity of analogues with different substituents at the glucosyl position.

Topics: Alcoholism; Aldehyde Dehydrogenase; Aldehyde Dehydrogenase 1 Family; Aldehyde Dehydrogenase, Mitochondrial; Animals; Behavior, Addictive; Binding Sites; Cricetinae; Crystallography, X-Ray; Humans; Isoenzymes; Isoflavones; Mitochondria; Models, Molecular; Molecular Structure; Retinal Dehydrogenase; Structure-Activity Relationship