Genotoxic effects of Microcystin-LR in Mammalian cells

Microcystin-LR (MC-LR) is a heptapeptidic toxin produced by cyanobacteria. However, the genotoxic effects of MC-LR are still contrary. This study is focused on the DNA damage induced by MC-LR in human-hamster hybrid A(L) cell line, which is sensitive to various toxic factors. Our present data showed that MC-LR at a concentration of 0.1 mu g/ml had slight effect on the celluar ATP contents and the colony formation of AL cells with either 1-, 3-, 7-, 15- or 30-day treatment. However, with 30-day treatment, the micronucleus frequency with 0.1 mu g/ml was increased about 1.6-fold compared to the negative control. These data suggested that MC-LR was genotoxic to mammalian cells with minimal cytotoxicity.