Subchronic mycotoxicoses in Wistar rats: Assessment of the in vivo and in vitro genotoxicity

MARTÍN G. THEUMER; MARÍA C. CÁNEPA; ABEL G. LÓPEZ; VERÓNICA S. MARY; JOSÉ S. DAMBOLENA; HÉCTOR R. RUBINSTEIN

TOXICOLOGY

ELSEVIER IRELAND LTD

Lugar: Amsterdam ; Año: 2010 vol. 268 p. 104 - 110

0300-483X

Some evidence suggests that fumonisin B1 (FB1), a worldwide toxic contaminant of grains produced by Fusarium verticillioides, exhibits an oxidative-stress mediated genotoxicity. We studied the DNA damage (by the alkaline comet and the micronucleus tests) and biomarkers of cellular oxidative stress (malondialdehyde, MDA; catalase, CAT; and superoxide dismutase, SOD) in spleen mononuclear cells of male Wistar rats subchronically (90 days) fed on a control experimental diet (CED) or poisoned with experimental diets contaminated with a culture material containing 100 ppm of FB1 (FED), with 40 ppb of aflatoxin B1 (a common toxic co-contaminant in cereals, AFB1ED), and with a mixture of both toxins (MED). The DNA damage was found in 13.7, 81.7, 98.0 and 99.3% (comet assay) and in 2.8, 7.0, 10.8 and 8.8% (micronucleus technique) in groups CED, FED, AFB1ED and MED, respectively. The MDA  levels as well as the CAT and SOD activities were increased in all the poisoned animals. A similar behavior was observed in cells exposed in vitro to the toxins. These data support the hypothesis of an oxidative-stress mediated genotoxicity induced by FB1. Furthermore, the extent of DNA damage assessed by the comet assaysuggests a possible protective effect of the fumonisins-AFB1 mixtures in vitro against the genotoxicity induced individually by the toxins.