Protection of organ specific genotoxic effects of 2-amino-3-methylimidazo[4,5-F] quinoline (Iq) by benzyl isothiocyanate (Bitc), glucotropaeolin (Gt)and garden cress juice in in vivo single cell gel electrophoresis (Scge) assay with primary rat hepatocytes and colonocytes

The single cell gel electrophoresis (SCGE) assay also known as comet assay is a relatively new genotoxicity test that detects, among other kinds of ge notoxic effects, single and double strand breaks, alkali labile sites and D NA-cross linking. We employed the SCGE assay in vivo to assess genotoxic ef fects of IQ in organs of rats which are amenable to develop tumor upon trea tment of the animals with the carcinogen. In subsequent experiments, we inv estigated the potential protective effects of benzyl isothiocyanate (BITC), glucotropaeolin (GT) and garden cress (GC) juice against the effects of IQ . The results showed a concordance between findings in SCGE assay and long term carcinogenicity tests in that pronounced genotoxic effects were induce d in organs of rats where tumors were preferentially induced by IQ. These e ffects were drastically reduced upon pretreatment with BITC, GT and GC juic e for three consecutive days. The antigenotoxic effect of BITC, GT, and GC juice might be attributed, at least partly, to induction of glutathione S- transferase (GST) and UDP-glucuronyl transferase (UDPGT) by these agents. I n conclusion, SCGE assay was found to be sensitive enough to detect the gen otoxicity of IQ and it could also be applied to identify dietary protective substances.