NADH is the reduced form of nicotinamide adenine dinucleotide (NAD) that can donate electrons as part of a reducing reaction. In that process, NADH becomes oxidized to produce NAD⁺. A variety of enzymes use NADH plus H⁺to reduce substrates, generating NAD⁺as well as the reduced product.^1,2,3For example, NADH:ubiquinone oxidoreductase accepts two electrons from NADH and passes them to ubiquinone (coenzyme Q) as part of the mitochondrial electron transport chain.³

1.Kim, M.S., and Kim, Y.J.Enzymatic properties of the membrane-bound NADH oxidase system in the aerobic respiratory chain of Bacillus cereusJournal of Biochemistry and Molecular Biology37(6)753-756(2004) 2.Godber, B.L.J., Doel, J.J., Sapkota, G.P., et al.Reduction of nitrite to nitric oxide catalyzed by xanthine oxidoreductaseThe Journal of Biological Chemisty275(11)7757-7763(2000) 3.Fato, R., Bergamini, C., Bortolus, M., et al.Differential effects of mitochondrial Complex I inhibitors on production of reactive oxygen speciesBiochim.Biophys.Acta.1787(5)384-392(2009)