Involvement of oxidative stress in the hepatotoxicity induced by aromatic antiepileptic drugs.
The use of the classic aromatic antiepileptic drugs (AAEDs) has recently been expanded to a broad spectrum of psychiatric and neurological disorders. However, the clinical use of these drugs is limited by several adverse effects, mainly idiosyncratic hepatotoxicity. AAED-induced hepatotoxicity has been attributed to a defective detoxification by the epoxide hydrolase and accumulation of arene oxides. The underlying mechanism has been proposed as immune-mediated, but direct toxicity has also been suggested. In general, idiosyncratic drug-induced hepatotoxicity may be mediated, at least in part, by oxidative stress. On the other hand, the oxidative stress induced by the AAED metabolites has not been demonstrated yet. Therefore, in the present study we have evaluated the induction of oxidative stress by three classical AAEDs: carbamazepine, phenytoin and phenobarbital as well as by their metabolites. The toxic effects of the metabolites were evaluated by incubating the drug with rat liver microsomes. The AAED-induced oxidative stress was demonstrated by the increased malondialdehyde levels, oxidation of cardiolipin; oxidation of sulfhydryl proteins and alteration of the cellular redox status. Results suggest that the hepatotoxicity associated with AAED might be mediated by the oxidative stress induced by the drugs metabolites.
Santos
N A G
NA
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - USP, Avenida do Café s/n, 14040-903 Ribeirão Preto, SP, Brazil.
Medina
W S G
WS
Martins
N M
NM
Rodrigues
M A Carvalho
MA
Curti
C
C
Santos
A C
AC
D000818:Animals; D000927:Anticonvulsants / Q000378:metabolism / Q000633:toxicity*; D002220:Carbamazepine / Q000378:metabolism / Q000633:toxicity; D002308:Cardiolipins / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008862:Microsomes, Liver / Q000187:drug effects* / Q000378:metabolism; D008930:Mitochondria, Liver / Q000187:drug effects; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D010634:Phenobarbital / Q000378:metabolism / Q000633:toxicity; D010672:Phenytoin / Q000378:metabolism / Q000633:toxicity; D051381:Rats; D017208:Rats, Wistar; D013438:Sulfhydryl Compounds / Q000378:metabolism; D018675:Toxicity Tests
D000927:Anticonvulsants; D002308:Cardiolipins; D013438:Sulfhydryl Compounds; D002220:Carbamazepine; D008315:Malondialdehyde; D010672:Phenytoin; D010634:Phenobarbital