The liver is the main site of systemic alcohol metabolism, where most alcohol is first oxidized to acetaldehyde and then to acetate (2). These reactions are primarily catalyzed by the enzymes ADH and ALDH (Figure 3). This oxidation process involves the reduction of nicotinamide adenine dinucleotide (NAD+) to NADH, causing a significant shift in the liver’s redox state that can contribute to various metabolic disorders, including hypoglycemia, hyperlactacidemia, and fat accumulation (110). The microsomal ethanol-oxidizing system (MEOS), along with catalase, also contributes to alcohol metabolism and related cytotoxicity under certain conditions (111). In what follows, we describe each of the four enzyme systems: ADH, MEOS, catalase, and ALDH.
