Protective effects of antioxidants on micronuclei induced by camphorquinone/N,N-dimethyl-p-toluidine employing in vitro mammalian test system.
Camphorquinone (CQ) is widely used as an initiator in modern visible-light (VL) cured resin systems. CQ is also characterized as a potential allergenic compound. To date, there is growing concern that CQ may produce genetic damage by inducing mutation. In this study, CQ in the presence of reducing agent N,N-dimethyl-p-toluidine (DMT) with or without VL irradiation was analyzed for the induction of chromosomal aberrations indicated by micronuclei (MN) induced in CHO cells. Our data demonstrated that an increase in the numbers of MN was observed with CQ/DMT with or without VL irradiation (p < 0.05). Significant prolongation of cell cycles was observed by the treatment with CQ/DMT with or without VL irradiation (p < 0.05). In addition, VL irradiated CQ/DMT was found to exhibit significantly genotoxic and cytotoxic effects as compared with CQ/DMT alone (p < 0.05). Furthermore, to determine whether oxidative stress could modulate the MN induced by CQ/DMT with or without VL irradiation in CHO cells, cells were pre-treated with various antioxidants 10 mM N-acetyl-L-cysteine (NAC), 2 mM ascorbic acid, and 2 mM alpha-tocopherol. The pre-treatment with antioxidants could antagonize not only the increased MN cells but also the prolonged cell cycle induced by CQ/DMT with or without VL irradiation in CHO cells (p < 0.05). Our findings provide the evidences for the induction of MN by CQ/DMT employing mammalian test system, indicating clastogenic activity of CQ/DMT with or without VL irradiation in vitro. In addition, VL irradiated CQ/DMT exhibits higher genotoxic and cytotoxic effects than CQ/DMT alone. Moreover, NAC, ascorbic acid, and alpha-tocopherol act as the antagonists against the genotoxicity and cytotoxicity of CQ/DMT with or without VL irradiation.
Li
Yi-Ching
YC
Department of Pharmacology, Chung Shan Medical University, Taichung, Taiwan.
Huang
Fu-Mei
FM
Lee
Shiaun-Shinn
SS
Lin
Ruey-Hseng
RH
Chang
Yu-Chao
YC
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D004249:DNA Damage / Q000187:drug effects*; D008027:Light; D048629:Micronuclei, Chromosome-Defective / Q000187:drug effects*; D020011:Protective Agents / Q000494:pharmacology*; D013729:Terpenes / Q000037:antagonists & inhibitors* / Q000633:toxicity; D014052:Toluidines / Q000037:antagonists & inhibitors* / Q000633:toxicity
D000975:Antioxidants; D020011:Protective Agents; D013729:Terpenes; D014052:Toluidines; C048339:camphoroquinone; C015835:dimethyl-4-toluidine