Green Algae Can Modulate the Genotoxic Action of Cadmium in Human Lymphocytes

ABSTRACT

In this paper we aimed to evaluate the cytotoxic, genotoxic and modulating potential of algal supernatants isolated from untreated cell suspension—SN(-), from algal cell suspension treated with CdCl₂ 10⁻⁶, 10⁻⁵ and 10⁻⁴ mol/l (SN), and from untreated algal cell suspension supplemented with various concentrations of CdCl₂—10⁻⁶, 10⁻⁵ and 10⁻⁴ mol/l—SN(+). All data were compared with the cytotoxic and genotoxic effects of single cadmium treatment.

Direct mutagenic assay and Cell-free medium/Lymphocytes assay were performed. Cell-wall-less strain cw15 of Chlamydomonas reinhardtii was grown for further procedures. Human lymphocytes were used as a valuable test system. The cytotoxic potential was evaluated on the basis of mitotic index (MI). The genotoxic potential was analysed on the basis of chromatid aberrations (CA).

The data demonstrated that the supernatants SN(-), SN and SN(+) enhanced the mitotic activity of the cells comparing with single cadmium treatment. The most pronounced decreasing of the level of chromosome disturbances compared with the single cadmium treatment was seen only in the samples incubated with SN from algal suspension treated with the highest concentration of CdCl₂—10⁻⁴ mol/l.

Promising experimental evidence was provided that the cytotoxic and genotoxic effect of cadmium could be modulated as a result of the living activity of Chlamydomonas reinhardtii. The mode of action depends on the concentrations and the type of supernatants.

Keywords:

• cadmium
• Chlamydomonas reinhardtii
• human lymphocyte test-system
• supernatants
• genotoxicity
• cytotoxicity