Roy Madhumita, Sinha Dona, Mukherjee Sutapa, Paul Susmita, Bhattacharya R K
Department of Environmental Carcinogenesis and Toxicology, Chittaranjan National Cancer Institute, 37, S P Mukherjee Road, Kolkata 700 026, India.
Indian J Exp Biol. 2008 Oct;46(10):690-7.
Chronic arsenic exposure causes skin diseases, gastrointestinal and neurological disorders, diabetes and cancer in various organs. Oxidative stress associated with arsenic exposure cause genetic instabilities and may initiate carcinogenesis. Phytochemicals present in vegetables, fruits, spices, tea, and medicinal plants, have shown to suppress experimental carcinogenesis in various organs. The aim of the present study was to elucidate the protective effect of some of the phytochemicals against the arsenite induced DNA damage in normal mammalian V79 cells. Comet assay was used for assessment of DNA damage and 2', 7'-dichlorofluorescein dihydroacetate for estimation of ROS generated by arsenite. The effect of the phytochemicals was observed during simultaneous treatment with arsenic, before arsenite exposure and during repair experiments. Of all the phytochemicals tested against arsenic, curcumin gave better protection during simultaneous treatment and resveratrol during pre treatment, which was evident both from comet assay and ROS generation experiments. During pre treatment a longer duration of treatment with lower dose of phytochemicals proved fruitful in reducing the genotoxicity. During repair experiments the phytochemicals enhanced recovery of DNA damage and ellagic acid gave promising results. The results indicated that natural phytochemicals may have the efficacy in reducing arsenic induced genotoxicity, in scavenging ROS and in enhancing the process of DNA repair in V79 cells.
长期接触砷会引发皮肤疾病、胃肠道和神经系统紊乱、糖尿病以及各器官癌症。与砷接触相关的氧化应激会导致基因不稳定，并可能引发癌症。蔬菜、水果、香料、茶和药用植物中的植物化学物质已显示出能抑制各器官的实验性致癌作用。本研究的目的是阐明某些植物化学物质对亚砷酸盐诱导的正常哺乳动物V79细胞DNA损伤的保护作用。采用彗星试验评估DNA损伤，用二氢乙酸2',7'-二氯荧光素评估亚砷酸盐产生的活性氧。在与砷同时处理、亚砷酸盐暴露前以及修复实验期间观察植物化学物质的作用。在所有针对砷测试的植物化学物质中，姜黄素在同时处理期间提供了更好的保护，白藜芦醇在预处理期间效果更佳，这在彗星试验和活性氧生成实验中均很明显。在预处理期间，用较低剂量的植物化学物质进行较长时间的处理在降低遗传毒性方面成效显著。在修复实验中，植物化学物质增强了DNA损伤的恢复，鞣花酸给出了有前景的结果。结果表明，天然植物化学物质可能在降低砷诱导的遗传毒性、清除活性氧以及增强V79细胞的DNA修复过程方面具有功效。
