MEOS oxidizes ethanol to acetaldehyde

Stable Identifier
Reaction [transition]
Homo sapiens
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The MEOS (microsomal ethanol oxidizing system) is an accessory pathway in the liver which increases in activity on chronic alcohol induction. The MEOS utilizes a cytochrome P450 which has since been deciphered to be CYP2E1, an ethanol-inducible form of P450. CYP2E1 also increases acetaldehyde formation and free radicals which can initiate lipid peroxidation. CYP2E1 can also activate many over-the-counter medicines and solvents to toxic metabolites and deplete retinoids resulting in their depletion and deletrious effects. This is because, being a cytochrome P450 and using NADPH and oxygen, it has the ability to biotransform drugs when it has been induced by ethanol.

Literature References
PubMed ID Title Journal Year
8627510 Microsomal ethanol oxidizing system activity by human hepatic cytochrome P450s

Monna, T, Asai, H, Funae, Y, Imaoka, S, Kuroki, T

J Pharmacol Exp Ther 1996
9028626 Ethanol metabolism, cirrhosis and alcoholism

Lieber, CS

Clin Chim Acta 1997
9884161 Respective roles of human cytochrome P-4502E1, 1A2, and 3A4 in the hepatic microsomal ethanol oxidizing system

Tsyrlov, IB, Salmela, KS, Lieber, CS, Kessova, IG

Alcohol Clin Exp Res 1998
Catalyst Activity

monooxygenase activity of Cytochrome P450 (CYP2E1 based) [endoplasmic reticulum membrane]

Orthologous Events
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