In vivo involvement of cytochrome P450 4A family in the oxidative metabolism of the lipid peroxidation product trans-4-hydroxy-2-nonenal, using PPARalpha-deficient mice.
Trans-4-hydroxy-2-nonenal (HNE) is a potent cytotoxic and genotoxic compound originating from the peroxidation of n-6 polyunsaturated fatty acids. Its metabolism has been previously studied in the rat (Alary et al. 1995. Chem. Res. Toxicol., 8: 35-39). In addition to major urinary mercapturic derivatives, some polar urinary metabolites were isolated and could correspond to hydroxylated compounds. 4-Hydroxynonenoic acid (HNA), resulting from the oxidation of the HNE carbonyl group, is a medium chain fatty acid and its omega-hydroxylation might be hypothesized. Therefore, the involvement of the CYP 4A family isoenzymes in the metabolism of [3H]HNE has been investigated in vivo using inducer treatments (fibrates) in wild-type or in peroxisome proliferator-activated receptor alpha (PPARalpha)-deficient mice. In wild-type mice, but not in PPARalpha (-/-) mice, fibrate treatments resulted in an increase of two urinary metabolites characterized, after HPLC purifications and mass spectrometry analyses, as the omega-hydroxylated metabolite of HNA, i.e., 4,9-dihydroxy-2-nonenoic acid, and its oxidized form, 4-hydroxy-2-nonene-1,9-dicarboxylic acid. The formation of the latter is correlated accurately to laurate hydroxylase activity studied concurrently in microsomes prepared from the liver of these animals. Basal levels of these two metabolites were measured in urine of normal and PPARalpha-deficient mice. These results are in accord with an implication of the P450 4A family in the extended oxidative metabolism of 4-HNE.
Guéraud
F
F
INRA, Laboratoire des Xénobiotiques, 180 ch. de Tournefeuille, B.P. 3, 31931 Toulouse Cedex 9, France.
Alary
J
J
Costet
P
P
Debrauwer
L
L
Dolo
L
L
Pineau
T
T
Paris
A
A
D000447:Aldehydes / Q000378:metabolism*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002994:Clofibrate / Q000494:pharmacology; D042926:Cytochrome P-450 CYP4A; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism*; D005260:Female; D011345:Fenofibrate / Q000494:pharmacology; D006900:Hydroxylation; D000960:Hypolipidemic Agents / Q000494:pharmacology; D015227:Lipid Peroxidation; D008297:Male; D013058:Mass Spectrometry; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008830:Microbodies / Q000187:drug effects; D008862:Microsomes, Liver / Q000201:enzymology; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism*; D010084:Oxidation-Reduction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear / Q000172:deficiency* / Q000235:genetics; D014157:Transcription Factors / Q000172:deficiency* / Q000235:genetics
D000447:Aldehydes; D000960:Hypolipidemic Agents; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D042926:Cytochrome P-450 CYP4A; D002994:Clofibrate; C027576:4-hydroxy-2-nonenal; D011345:Fenofibrate