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Journal of Environmental Pathology, Toxicology and Oncology
Impact-faktor: 1.241 5-jähriger Impact-Faktor: 1.349 SJR: 0.356 SNIP: 0.613 CiteScore™: 1.61

ISSN Druckformat: 0731-8898
ISSN Online: 2162-6537

Journal of Environmental Pathology, Toxicology and Oncology

DOI: 10.1615/JEnvironPatholToxicolOncol.v20.i1.70
8 pages

Effect of Caffeine on the Genotoxic Effects of Gamma Radiation and 4-NQO in Diploid Yeast

Kshiti B. Anjaria
Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai, India
Badanidiyoor S. Rao
Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai, India

ABSTRAKT

Caffeine is an environmental agent to which people are commonly exposed through medicines, drinks, food items, etc. It has been shown to be mutagenic in a number of test systems. In addition, it has also been shown to modify the mutagenic response of ionizing radiation, UV, and several chemical mutagens in a number of test systems.We have studied the effect of caffeine on gamma radiation and 4-Nitroquinoline 1-oxide (4-NQO)-induced gene conversion in the yeast Saccharomyces cerevisiae D7. Stationary phase cells were either exposed to 100-600 Gy of 60Co gamma radiation or treated with 0.15-0.3 μM 4-NQO (30°C, 1 hour), after which they were plated on synthetic complete or minimal media with or without caffeine. Caffeine concentrations ranged from 5 to 15 mM. The results indicated that caffeine at 5 and 10 mM decreased gamma radiation-induced gene conversion frequencies significantly at 400 and 600 Gy. At 600 Gy, the decrease was about 30% and 50% with caffeine concentrations of 5 and 10 mM, respectively. In contrast, caffeine was found to increase the induced gene conversion frequency when cells treated with 0.15, 0.225, and 0.3 μM 4-NQO were plated on media containing caffeine. The increase with 5, 10, and 15 mM caffeine was approximately 1.5, 2, and 2.5, respectively, times the value of 4-NQO alone. The results indicate that the posttreatment repair processes following gamma irradiation or 4-NQO treatment are modified via different pathways.