Toxicology International (Formerly Indian Journal of Toxicology)

G. Prakash ¹, B. B. Hosetti ¹, B. L. Dhananjaya ²

Affiliations
1 Department of Applied Zoology, Kuvempu University, Shankaraghatta, Karnataka, IN
2 Toxinology/Toxicology and Drug Discovery Unit, Centre for Emerging Technologies, Jain Global Campus, Jain University, Kanakapura Taluk, Bangalore, Karnataka, IN

Abstract

Objectives: Plants as dietary sources are known to have several chemoprotective agents. Dioscorea pentaphylla is an important medicinal plant, which is often used as edible food. This study was undertaken to evaluate the antigenotoxic potential of D. pentaphylla extracts on the genotoxic effect induced by methyl methanesulfonate (MMS) in the Drosophila wing spot test. Materials and Methods: The somatic mutation and recombination test (SMART) was carried out in Drosophila melanogaster. In transheterogyous larvae, multiple wing hair (mwh 3‑0.3) and flare (flr3‑38.8) genes were used as markers of the extent of mutagenicity. Results: It was observed thatall the three extracts (petroleum ether, choloroform, and ethyl alcohol) in the combined treatment had significantly inhibited the effect of MMS‑induced genotoxic effects. When compared to others, the ethanol extract showed a very significant antimutagenic activity. Conclusion: The compounds that are present in the extracts may directly interact with the methyl radical groups of MMS and inactivate them by chemical reaction. It is also possible that the compounds in the extract compete to interact with the nucleophilic sites in deoxyribonucleic acid (DNA), thus altering the binding of the mutagen to these sites. Although our results indicate that the compounds present in the extracts may directly interact with the methyl radical groups of MMS and inactivate them by chemical reaction, it may also be quite interesting to investigate through the other different mechanisms by which D. pentaphyllacould interfere in vivo on the effect of genotoxic agents.

Keywords

Antigenotoxicity, antioxidant, chemoprotective agents, diascoria pentaphylla, drosophila melanogaster, methyl methanesulfonate

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G. Prakash , B. B. Hosetti , B. L. Dhananjaya

Abstract

Objectives: The antimutagenic effect of caffeine is evaluated against ethyl methanesulfonate (EMS)-induced mutation rate in Drosophila. Materials and Methods: The mutation rate is evaluated using wing mosaic assay. In transheterozygous larvae, multiple wing hair (mwh 0.3-3) and flare (flr 3-38.8) genes were used as markers of the extent of mutagenicity. Results: The results at 0.5 and 1.0 mM EMS concentration at both 48 ± 4 and 72 ± 4 h have shown consistent increase in mutation rate, which was being measured as frequency of clone formation per 105 cells. Toxicity of caffeine at 5 mM concentration was parallel to that of distilled water alone. At 0.5 mM EMS concentration at 42 ± 4 and 72 ± 4 h, Drosophila larvae mutation rate was significantly increased. Although caffeine prevented mutation rate in all pre, post, and combined treatment, it was more significant in pretreatment experiments where it was found to be effective in reducing the genotoxicity of EMS. However, the concentration of caffeine as recommended in dietary allowance did not induce the frequency of mutant clones in somatic mutation and recombination test (SMART) recorded. Conclusion: This study shows that caffeine significantly reduced the genotoxicity induced by EMS. However, the limitation in completely abolishing genotoxicity induced by EMS as observed at the dietary allowance of caffeine makes it interesting for further in-depth study. Further studies on the molecular mechanism of antigenotoxic effect of caffeine will also be interesting.

Keywords

Antimutagenicity, caffeine, drosophila melanogaster, ethyl methanesulfonate

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