Formation of 4-hydroxy-2-nonenal-modified proteins in the renal proximal tubules of rats treated with a renal carcinogen, ferric nitrilotriacetate.
An iron chelate, ferric nitrilotriacetate (Fe-NTA), induces proximal tubular necrosis, a consequence of lipid peroxidation, that finally leads to a high incidence of renal adenocarcinoma in rodents. Lipid peroxidation as monitored by formation of thiobarbituric acid-reactive substances and free 4-hydroxy-2-nonenal (HNE) was observed in the kidney homogenates of rats treated with Fe-NTA. Based on the fact that HNE is capable of reacting with cellular proteins, we attempted to detect the localization of HNE-modified proteins in rat kidney tissues with an immunohistochemical procedure. By means of an immunohistochemical technique using polyclonal antibody against the HNE-modified proteins, it was shown that HNE-modified proteins are formed in the target cells of this carcinogenesis model. HNE-modified proteins were detected in the renal proximal tubules 1 hr after i.p. administration of Fe-NTA (15 mg of iron per kg). Intense positivity was found in the cells with degeneration. After 6 hr, the level of HNE-protein conjugates decreased due to the subsequent necrosis. The intensity of the immunochemical reaction with HNE-modified proteins increased in parallel with an increase in the amounts of thiobartituric acid-reactive substances and free HNE that were found. Furthermore, histochemical detection of aldehydes by cold Schiff's reagent demonstrated that location of aldehydes was identical to that of the HNE-modified proteins determined by immunohistochemical procedures. It would thus appear that the production of HNE, a genotoxic and mutagenic aldehyde, and its reaction with proteins may play a role in Fe-NTA-induced renal carcinogenesis.
Toyokuni
S
S
Department of Pathology, Faculty of Medicine, Kyoto University, Japan.
Uchida
K
K
Okamoto
K
K
Hattori-Nakakuki
Y
Y
Hiai
H
H
Stadtman
E R
ER
D000447:Aldehydes / Q000378:metabolism*; D000818:Animals; D002273:Carcinogens / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005290:Ferric Compounds / Q000494:pharmacology*; D006651:Histocytochemistry; D007150:Immunohistochemistry; D007672:Kidney Cortex / Q000187:drug effects / Q000473:pathology; D007687:Kidney Tubules, Proximal / Q000187:drug effects* / Q000473:pathology; D008297:Male; D009571:Nitrilotriacetic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D013997:Time Factors
D000447:Aldehydes; D002273:Carcinogens; D005290:Ferric Compounds; D011506:Proteins; D017392:Thiobarbituric Acid Reactive Substances; C027576:4-hydroxy-2-nonenal; D009571:Nitrilotriacetic Acid; C020326:ferric nitrilotriacetate