title: Acetaminophen-induced cytotoxicity on human normal liver L-02 cells and the protection of antioxidants.
abstract: In vitro cell models, which can partially mimic in vivo responses, offer potentially sensitive tools for toxicological assessment. The objective of this study was to explore the possible mechanisms of acetaminophen (AP)-induced toxicity in human normal liver L-02 cells. The expression of the CYP2E1 enzyme, which is reported to transform AP to its toxic metabolites, was higher in L-02 than in Hep3B cells. Further cell viability and reduced glutathione (GSH) depletion after AP treatment were examined. After exposure to AP for 24 h, cell viability decreased in a concentration-dependent manner. Concentration-dependent GSH depletion was also observed after AP treatment for 48 h, indicating oxidative stress had occurred in L-02 cells. The effects of D, L-buthionine-(S, R)-sulfoximine (BSO), an inhibitor of GSH biosynthesis, and N-acetylcysteine (NAC), a precursor of GSH synthesis, on the cytotoxicity induced by AP were also investigated. BSO aggravated the cytotoxicity induced by AP while NAC ameliorated such cell death. Further results showed that 10 mM AP caused cell apoptosis after 48 h treatment based on the DNA fragmentation assay and western blot of caspase-3 activation, respectively. In addition, the protective effects of various well-known antioxidants against AP-induced hepatotoxicity were observed. Taken together, these results indicate that oxidative stress and cellular apoptosis are involved in AP-induced toxicity in human normal liver L-02 cells, and this cell line is a suitable in vitro cell model for AP hepatotoxicity study.
authors.affiliation: The MOE Key Laboratory for Standardization of Chinese Medicines and The SATCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, PR China.
authors.forename: Qingning
authors.initials: Q
authors.lastname: Liang
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Sheng
authors.forename: Lili
authors.initials: L
authors.lastname: Ji
authors.forename: Yang
authors.initials: Y
authors.lastname: Min
authors.forename: Yuye
authors.initials: Y
authors.lastname: Xia
authors.forename: Zhengtao
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000082:Acetaminophen / Q000633:toxicity*; D018712:Analgesics, Non-Narcotic / Q000633:toxicity*; D000975:Antioxidants / Q000378:metabolism*; D019328:Buthionine Sulfoximine / Q000633:toxicity; D002460:Cell Line; D019392:Cytochrome P-450 CYP2E1 / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000187:drug effects* / Q000201:enzymology; D018384:Oxidative Stress / Q000187:drug effects
chemical_list: D018712:Analgesics, Non-Narcotic; D000975:Antioxidants; D000082:Acetaminophen; D019328:Buthionine Sulfoximine; D019392:Cytochrome P-450 CYP2E1