Antimutagenic activity of two medicinal phytoextracts in somatic cells of Drosophila melanogaster.

CONTEXT AND OBJECTIVE

We used the wing somatic assay in Drosophila melanogaster to test the hypothesis that two phytoextracts from Cecropia obtusifolia Bertol (Cecropiaceae) and Equisetum myriochaetum Schlecht. et Cham (Equisetaceae), which are used in folk medicine to treat type 2 diabetes mellitus, could detoxify the mutagen hydrogen peroxide.

MATERIALS AND METHODS

Third instar larvae from standard (ST) and high-bioactivation (HB) crosses were chronically exposed to different concentrations of the phytoextracts. Hydrogen peroxide was used to induce oxidative stress and was chronically tested in both crosses. Catalase activity was measured in larvae of both strains 48 h after treatment with hydrogen peroxide. A pretreatment protocol was devised to test the antimutagenic potency of the medicinal extracts.

RESULTS

The present study showed that neither of the phytoextracts were genotoxic in Drosophila. Interestingly, the antioxidant enzyme activity levels were different between the larvae. Hydrogen peroxide resulted in a significant genotoxic effect in the ST cross, whereas a detoxification of hydrogen peroxide was found in the HB cross. Thus, catalase was stimulated in the HB cross, which was indicative of a cellular defense mechanism mounted against a xenobiotic hazard. We found that the percentage of inhibition of spots produced by E. myriochaetum was much higher than that induced by Cecropia obtusifolia.

DISCUSSION AND CONCLUSIONS

These results are in agreement with the uses of these phytoextracts in traditional medicine. Indeed, the lack of genotoxicity and the antimutagenic activity observed for both phytoextracts validates their use as a therapeutic modality to treat diabetic patients. Moreover, these extracts are suitable for consumption as teas and/or phytomedicines.