Division of Radiation Biosciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India.
Radiat Res. 2011 Nov;176(5):613-23. doi: 10.1667/rr2661.1. Epub 2011 Sep 7.
Protection against radiation-induced DNA strand breaks is an important aspect in the design and development of a radioprotector. In this study, the radioprotective efficacy of sesamol, a natural antioxidant, was investigated in aqueous solution of plasmid DNA (pBR322) and compared with that of melatonin, a known antioxidant-based radioprotector. Thermal denaturation studies on irradiated calf thymus DNA were also carried out with sesamol and melatonin. Sesamol demonstrated greater radioprotective efficacy in both plasmid DNA and calf thymus DNA. To assess the radical scavenging capacity of sesamol and melatonin, 2-deoxyribose degradation, DPPH and ABTS assays were performed. Sesamol exhibited more scavenging capacity compared to melatonin. In vitro studies with V79 cells showed that sesamol is 20 times more potent than melatonin. It is proposed that the greater radioprotective efficacy of sesamol could be due to its greater capacity for scavenging of free radicals compared to melatonin. The results will be helpful in understanding the mechanisms and development of sesamol as a radioprotector.
防止辐射引起的 DNA 链断裂是设计和开发辐射防护剂的一个重要方面。在这项研究中，研究了天然抗氧化剂芝麻酚在质粒 DNA（pBR322）水溶液中的辐射防护效果，并将其与已知的基于抗氧化剂的辐射防护剂褪黑素进行了比较。还对芝麻酚和褪黑素处理的小牛胸腺 DNA 进行了热变性研究。芝麻酚在质粒 DNA 和小牛胸腺 DNA 中均表现出更强的辐射防护效果。为了评估芝麻酚和褪黑素的自由基清除能力，进行了 2-脱氧核糖降解、DPPH 和 ABTS 测定。芝麻酚的清除能力比褪黑素更强。V79 细胞的体外研究表明，芝麻酚的效力比褪黑素强 20 倍。据推测，芝麻酚的辐射防护效果更强，可能是因为其清除自由基的能力比褪黑素更强。这些结果将有助于理解芝麻酚作为辐射防护剂的作用机制和发展。
