title: Evaluating the toxic potential of benzothiazoles with the rainbow trout cell lines, RTgill-W1 and RTL-W1.
abstract: Benzothiazole (BTHs) are environmental contaminants of emerging concern for which little toxicological information is available. Therefore the toxic potential of twelve BTHs was evaluated with two rainbow trout epithelial cell lines, RTgill-W1 and RTL-W1. The BTHs were benzothiazole (BTH), 3,3'-diethylthia dicarbocyanine iodide (DTDC), C.I. sulphur orange 1 (SO), 2-mercaptobenzothiazole (2MBTH), zinc 2-mercaptobenzothiazole (ZnMBTH), sodium 2-mercaptobenzothiazole (NaMBTH), 2-hydroxy-benzothiazole (OHBTH), 2- aminobenzothiazole (2ABTH), C.I. vat yellow 2 (VY), N,N-dicyclohexyl-2-benzothiazolsulfene amide (NNA), 2,2'-dithiobis (benzothiazole) (DBTH) and 2-(p-aminophenyl)-6-methylbenzothiazole-7-sulfonic acid (MBTHS). All BTHs, except for NNA, DBTH, and MBTHS, caused both cytotoxicity and a transitory elevation in reactive oxygen species (ROS) levels. Yet, neither N-acetyl cysteine (NAC) nor IM-54 inhibited cytotoxicity, suggesting that ROS imbalance did not contribute to cell death. Cell death was not blocked by Necrostatin-1 nor accompanied by DNA laddering, suggesting that neither necroptosis nor apoptosis took place. The comet assay revealed DNA strand breaks after exposures to 2ABTH and OHBTH for 1 day and to BTH for 12 days. In RTL-W1, cytochrome P4501A was induced noticeably by 2ABTH, OHBTH, and MBTHS and weakly by NaMBTH, ZnMBTH, SO, VY, and NNA, suggesting that these BTHs have the potential to alter xenobiotic metabolism and activate the aryl hydrocarbon receptor. In summary, several toxic actions were initiated in vitro by some but not all BTHs, warranting further study of these BTHs in vivo.
authors.affiliation: Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
authors.forename: Fanxing
authors.initials: F
authors.lastname: Zeng
authors.affiliation: Aquatic Contaminants Research Division, Environment Canada, Burlington, ON L7R 4A6, Canada.
authors.forename: James P
authors.initials: JP
authors.lastname: Sherry
authors.affiliation: Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada. Electronic address: ncbols@uwaterloo.ca.
authors.forename: Niels C
authors.initials: NC
authors.lastname: Bols
mesh_terms: D000818:Animals; D052160:Benzothiazoles / Q000378:metabolism / Q000633:toxicity*; D016923:Cell Death; D002460:Cell Line; D020552:Comet Assay; D004249:DNA Damage; D006835:Hydrazones; D007093:Imidazoles; D007211:Indoles; D017686:Oncorhynchus mykiss / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D018675:Toxicity Tests / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D052160:Benzothiazoles; D006835:Hydrazones; D007093:Imidazoles; D007211:Indoles; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; C507699:necrostatin-1; C005563:captax; C028000:dibenzothiazyl disulfide; C005465:benzothiazole; C002536:3-methyl-2-benzothiazolone hydrazone
keywords: Benzothiazoles; Cell lines; Cytochrome P4501A; Cytotoxicity; Fish; Genotoxicity