title: Evidence that 4-aminobiphenyl, benzidine, and benzidine congeners produce genotoxicity through reactive oxygen species.
abstract: 4-Aminobyphenyl (4-Ab), benzidine (Bz), and Bz congeners were evaluated for their ability to induce genotoxicity through an oxidative mechanism. The mutagenicity of these compounds was tested in the presence and absence of Aroclor 1254-induced rat S9 mix using Salmonella typhimurium tester strain TA102, which is sensitive to agents producing reactive oxygen species (ROS). In the presence of S9, 4-Ab, Bz, N-acetyl-benzidine, and 3,3-dimethoxybenzidine were strongly mutagenic in TA102, whereas, 3,3,5,5-tetra-methylbenzidine, 3,3-dimethylbenzidine (O-tolidine), and N,N-diacetylbenzidine were not mutagenic. In addition, 3,3-dichlorobenzidine and 4,4-dinitro-2-biphenylamine were directly mutagenic in TA102. Incorporation of the free radical and metal scavengers, catalase, superoxide dismutase (SOD), butylated hydroxytolune (BHT), and ethylenediamine tetraacetic acid (EDTA) reduced the mutagenic responses of 4-Ab and Bz, whereas heat-inactivated catalase and SOD had no effect. 4-Ab and Bz also induced lipid peroxidation in the presence of S9 mix as shown using the thiobarbituric acid reactive substances assay. The results of this study indicate that 4-Ab and Bz induce mutations through the induction of ROS.
authors: Department of Biology, The University of Memphis, Memphis, Tennessee, USA.
authors: Patrudu
authors: P
authors: Makena
authors: King-Thom
authors: KT
authors: Chung
mesh_terms: D015101:3,3'-Dichlorobenzidine / Q000737:chemistry / Q000633:toxicity; D000611:Aminobiphenyl Compounds / Q000737:chemistry / Q000633:toxicity*; D000818:Animals; D001560:Benzidines / Q000737:chemistry / Q000633:toxicity*; D002084:Butylated Hydroxytoluene / Q000494:pharmacology; D002374:Catalase / Q000494:pharmacology; D003962:Dianisidine / Q000737:chemistry / Q000633:toxicity; D004492:Edetic Acid / Q000494:pharmacology; D019787:Linoleic Acid / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D008954:Models, Biological; D015394:Molecular Structure; D009152:Mutagenicity Tests / Q000379:methods; D051381:Rats; D017382:Reactive Oxygen Species / Q000737:chemistry / Q000378:metabolism*; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics; D013482:Superoxide Dismutase / Q000494:pharmacology
chemical_list: D000611:Aminobiphenyl Compounds; D001560:Benzidines; D017382:Reactive Oxygen Species; D002084:Butylated Hydroxytoluene; D015101:3,3'-Dichlorobenzidine; C029876:benzidine; C009501:2-tolidine; D004492:Edetic Acid; D019787:Linoleic Acid; D002374:Catalase; D013482:Superoxide Dismutase; D003962:Dianisidine