4-hydroxy Nonenal Mercapturic Acid

4-hydroxy Nonenal Mercapturic Acid (4-HNE) is generated by the peroxidation of common ω-6 polyunsaturated fatty acids (PUFAs) such as linoleic acid, DGLA, and arachidonic acid. 4-hydroxy Nonenal Mercapturic Acid is rapidly cleared from plasma and enters the enterohepatic circulation in rats as a glutathione conjugate. Approximately two-thirds of 4-hydroxy Nonenal Mercapturic Acid is excreted in the urine within 48 hours, primarily as mercapturic acid conjugates. Approximately half of the metabolites are C-1 aldehydes of 4-hydroxy Nonenal Mercapturic Acid that are reduced to alcohols. The remainder are C-1 aldehydes or have been oxidized to C-1 carboxylic acids. These aldehydes and carboxylic acids can also form gamma-lactols and gamma-lactones, respectively, resulting in at least four or five final urinary metabolites of 4-HNE in vivo.