Genotoxicity of methylglyoxal: cytogenetic damage in human lymphocytes in vitro and in intestinal cells of mice.

The mutagenic activity of methylglyoxal (MG) was assayed in vitro in human lymphocytes [induction of chromosomal aberrations (CAs), sister chromatid exchanges (SCEs) and micronuclei] both in the presence and in the absence of metabolic activation (S9 mix). The Ames/microsome test was performed with the Salmonella typhimurium strains considered more responsive (TA102 and TA104). Positive results were obtained for all the genetic endpoints analysed. In human lymphocytes the activity of MG is decreased by the presence of S9 mix. In the in vivo studies, the metaphase analysis in the ileum and duodenum cells of mice treated per os with MG (400 and 600 mg/kg body wt) gave negative results for CA induction, while only a weak increase of SCE in duodenum cells at the higher dose was obtained. Dimethylhydrazine (25 mg/kg body wt), as positive control, was clearly active in inducing both CAs and SCEs in the same intestinal tissues.