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.
Ichihashi
K
K
Laboratory of Food and Biodynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
Osawa
T
T
Toyokuni
S
S
Uchida
K
K
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