Devipriya Nagarajan, Sudheer Adluri Ram, Srinivasan Marimuthu, Menon Venugopal P
Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar 608002, Tamil Nadu, India.
Mutat Res. 2008 Jun 30;654(1):1-7. doi: 10.1016/j.mrgentox.2008.03.003. Epub 2008 Mar 15.
We investigated the radioprotective efficacy of quercetin (QN), a naturally occurring flavonoid against gamma radiation-induced damage in human peripheral blood lymphocytes and plasmid DNA. In plasmid study, QN at different concentrations (3, 6, 12, 24 and 48 microM) were pre-incubated with plasmid DNA for 1h followed by exposure of 6 Gy radiation. Among all concentrations of QN used, 24 microM showed optimum radioprotective potential. To establish the most effective protective concentration of QN in lymphocytes, the cells were pre-incubated with 3, 6, 12, 24 and 48 microM of QN for 30 min and then exposed to 4 Gy gamma-radiation. The concentration-dependent effects of QN were evaluated by scoring micronuclei (MN) frequencies. The results showed that QN decreased the MN frequencies dose dependently, but the effect was more pronounced at 24 microM. Thus, 24 microM of QN was selected as the optimum concentration and was further used to evaluate its radioprotective effect in lymphocytes. For that a separate experiment was carried out, in which lymphocytes were incubated with QN (24 microM) for 30 min and exposed to different doses of radiation (1, 2, 3 and 4 Gy). Genetic damage (MN, dicentric aberration and comet attributes) and biochemical changes were measured to evaluate the effect of QN on gamma-radiations (1-4 Gy). Radiation exposed showed significant increases in the genetic damage and thiobarbituric acid reactive substances (TBARS) accompanied by a significant decrease in the antioxidant status. QN pretreatment significantly decreased the genetic damage and TBARS and improved antioxidant status through its antioxidant potential. Altogether, our findings encourage further mechanistic and in vivo studies to investigate radioprotective efficacy of QN.
我们研究了槲皮素（QN）——一种天然存在的类黄酮，对γ射线诱导的人类外周血淋巴细胞和质粒DNA损伤的辐射防护效果。在质粒研究中，将不同浓度（3、6、12、24和48微摩尔）的QN与质粒DNA预孵育1小时，随后进行6 Gy辐射照射。在所使用的所有QN浓度中，24微摩尔显示出最佳的辐射防护潜力。为确定QN在淋巴细胞中的最有效保护浓度，将细胞与3、6、12、24和48微摩尔的QN预孵育30分钟，然后暴露于4 Gy的γ射线下。通过对微核（MN）频率进行评分来评估QN的浓度依赖性效应。结果表明，QN剂量依赖性地降低了MN频率，但在24微摩尔时效果更显著。因此，选择24微摩尔的QN作为最佳浓度，并进一步用于评估其在淋巴细胞中的辐射防护效果。为此进行了一项单独的实验，其中淋巴细胞与QN（24微摩尔）孵育30分钟，并暴露于不同剂量的辐射（1、2、3和4 Gy）。测量遗传损伤（MN、双着丝粒畸变和彗星特征）和生化变化，以评估QN对γ射线（1 - 4 Gy）的影响。辐射暴露导致遗传损伤和硫代巴比妥酸反应性物质（TBARS）显著增加，同时抗氧化状态显著下降。QN预处理通过其抗氧化潜力显著降低了遗传损伤和TBARS，并改善了抗氧化状态。总之，我们的研究结果鼓励进一步开展机制研究和体内研究，以探究QN的辐射防护效果。
