Endogenous formation of protein adducts with carcinogenic aldehydes: implications for oxidative stress.
In the present study, we characterize the covalent modification of a protein by crotonaldehyde, a representative carcinogenic aldehyde, and describe the endogenous production of this aldehyde in vivo. The crotonaldehyde preferentially reacted with the lysine and histidine residues of bovine serum albumin and generated a protein-linked carbonyl derivative. Upon incubation with the histidine and lysine derivatives, crotonaldehyde predominantly generated beta-substituted butanal adducts of histidine and lysine and N(epsilon)-(2,5-dimethyl-3-formyl-3,4-dehydropiperidino)lysine (dimethyl-FDP-lysine) as the putative carbonyl derivatives generated in the crotonaldehyde-modified protein. To verify the endogenous formation of crotonaldehyde in vivo, we raised the monoclonal antibody (mAb82D3) against the crotonaldehyde-modified protein and found that it cross-reacted with the protein-bound 2-alkenals, such as crotonaldehyde, 2-pentenal, and 2-hexenal. The anti-2-alkenal antibody recognized multiple crotonaldehyde-lysine adducts, including dimethyl-FDP-lysine and an unknown product, which showed the greatest immunoreactivity with the antibody. On the basis of the chemical and spectroscopic evidence, the major antigenic product was determined to be a novel Schiff base-derived crotonaldehyde-lysine adduct, N(epsilon)-(5-ethyl-2-methylpyridinium)lysine (EMP-lysine). It was found that the lysine residues that had disappeared in the protein treated with crotonaldehyde were partially recovered by EMP-lysine. The presence of immunoreactive materials with mAb82D3 in vivo was demonstrated in the kidney of rats exposed to the renal carcinogen, ferric nitrilotriacetate. In addition, the observations that the metal-catalyzed oxidation of polyunsaturated fatty acids in the presence of proteins resulted in an increase in the antigenicity of the protein indicated that lipid peroxidation represents a potential pathway for the formation of crotonaldehyde/2-alkenals in vivo. These data suggest that the formation of carcinogenic aldehydes during lipid peroxidation may be causally involved in the pathophysiological effects associated with oxidative stress.
Laboratory of Food and Biodynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
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K
Ichihashi
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Osawa
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Toyokuni
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Uchida
D000447:Aldehydes / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D002273:Carcinogens / Q000494:pharmacology*; D005290:Ferric Compounds / Q000494:pharmacology*; D006639:Histidine / Q000737:chemistry; D007680:Kidney Neoplasms / Q000139:chemically induced / Q000378:metabolism; D007687:Kidney Tubules, Proximal / Q000187:drug effects / Q000378:metabolism; D015227:Lipid Peroxidation; D008239:Lysine / Q000031:analogs & derivatives / Q000096:biosynthesis* / Q000138:chemical synthesis / Q000737:chemistry / Q000276:immunology; D008297:Male; D008956:Models, Chemical; D009571:Nitrilotriacetic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology*; D018384:Oxidative Stress; D051381:Rats; D017208:Rats, Wistar; D012710:Serum Albumin, Bovine / Q000378:metabolism
D000447:Aldehydes; D000911:Antibodies, Monoclonal; D002273:Carcinogens; D005290:Ferric Compounds; C432403:N(epsilon)-(2,5-dimethyl-3-formyl-3,4-dehydropiperidino)lysine; C432404:N(epsilon)-(5-ethyl-2-methylpyridinium)lysine; D012710:Serum Albumin, Bovine; D006639:Histidine; C012796:2-butenal; D008239:Lysine; D009571:Nitrilotriacetic Acid; C020326:ferric nitrilotriacetate