title: Areca nut-induced micronuclei and cytokinesis failure in Chinese hamster ovary cells is related to reactive oxygen species production and actin filament deregulation.
abstract: Epidemiological studies have shown a strong association between environmental exposure to betel quid (BQ) and oral cancer. Areca nut (AN), an ingredient of BQ, contains genotoxic and mutagenic compounds. In this study, we found that AN extract (ANE) inhibited the growth of Chinese hamster ovary cells (CHO-K1) in a dose- and time-dependent manner. Intracellular reactive oxygen species (ROS) levels and micronuclei (MN) frequency were significantly increased following ANE treatment in CHO-K1 cells. Addition of catalase markedly inhibited ANE-induced MN formation, indicating that ANE-induced genotoxicity was correlated with intracellular H(2)O(2). Incubation of CHO-K1 cells with ANE (400-800 microg/ml) for 24 hr caused G2/M arrest, and prolonged exposure to ANE (800 microg/ml) significantly induced cell death. Surprisingly, ANE itself caused cytokinesis failure and subsequent increase in binucleated cell formation. Coexposure to catalase (2,000 U/ml) and ANE (800 microg/ml) reduced the generation of binucleated cells, indicating that ANE-induced cytokinesis failure was associated with oxidative stress. Following prolonged exposure to ANE, an accumulation of hyperploid/aneuploid cells concomitant with bi-, micro- or multinucleated cells was found. In summary, our results demonstrate that ANE exposure to CHO-K1 cells caused increased MN frequency, G2/M arrest, cytokinesis failure, and an accumulation of hyperploid/aneuploid cells. These events are associated with an increase in intracellular H(2)O(2) level and actin filament disorganization.
authors.affiliation: Department of Dentistry, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Chiu-Chun
authors.initials: CC
authors.lastname: Lin
authors.forename: Mei-Chi
authors.initials: MC
authors.lastname: Chang
authors.forename: Hsiao-Hua
authors.initials: HH
authors.lastname: Chang
authors.forename: Tong-Mei
authors.initials: TM
authors.lastname: Wang
authors.forename: Wan-Yu
authors.initials: WY
authors.lastname: Tseng
authors.forename: Tseng-Fang
authors.initials: TF
authors.lastname: Tai
authors.forename: Hung-Wei
authors.initials: HW
authors.lastname: Yeh
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Yang
authors.forename: Liang-Jiunn
authors.initials: LJ
authors.lastname: Hahn
authors.forename: Jiiang-Huei
authors.initials: JH
authors.lastname: Jeng
mesh_terms: D000199:Actins / Q000378:metabolism*; D000818:Animals; D001114:Areca / Q000737:chemistry*; D016466:CHO Cells; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D006224:Cricetinae; D003412:Cricetulus; D048749:Cytokinesis / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000378:metabolism; D048629:Micronuclei, Chromosome-Defective / Q000139:chemically induced*; D010936:Plant Extracts / Q000737:chemistry / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D000199:Actins; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide