Activation of a catalase peroxidative pathway for the oxidation of alcohols in mammalian erythrocytes

Abstract

Alcohol oxidation has been induced in hemolyzed and intact mammalian erythrocytes by activating a catalase peroxidative pathway. Although erythrocytes contain high concentrations of catalase they ordinarily do not oxidize alcohols, presumably because of low hydrogen peroxide levels. Activation of the hexose monophosphate shunt with methylene blue and glucose induced the oxidation of methanol and ethanol in intact red cells. Inosine and hexoses which are readily converted to glucose-6-phosphate replaced glucose, but they were less effective. Galactose, a sugar poorly metabolized by erythrocytes, did not replace glucose. 2-Deoxyglucose competitively inhibited the effect of glucose but did not alter the response due to inosine. Furthermore, the optimal rate of alcohol oxidation achieved with glucose and methylene blue was augmented by the addition of inosine. Requirements for alcohol oxidation by hemolysates include methylene blue and NADPH. Inhibition of catalase activity by 3-amino-1,2,4-triazole or reduction of hydrogen peroxide levels with reduced glutathione inhibited alcohol oxidation.