Radioprotectors: Nature’s Boon

Objective: To reduce the chances of toxicity, reduction in radiation dose or reducing the frequency of the therapy is done which usually leads to a therapeutically poor outcome. The most feasible method is to protect the normal cells by administration of radioprotective agents either before or after the exposure. These agents have been tested on animals and human cellmodels for evaluating theirsafety window and toxicityprofile at the cellular level. The study aims to compile the effective natural radioprotective agents available which can be further exploited by using certain QSAR studies to increase their potency. Method: Structured literature search from EMBASE, PubMed, Bentham Science, Scopus, and ScienceDirect was done and appropriate peer-reviewed review articles, as well as certain research articles, were included and compiled in this review paper. Conclusion: As various studies have indicated the harmful effects of ionizing radiations on normal cells, to reduce these effects radioprotective agents are used before or after exposure to radiations. Compounds derived from natural sources are proved to have few side effects and they possess radioprotective property due to the presence of alkaloids, resins, volatile oils, tannins in their molecular structure. Various plants having such radioprotective constitutes have been identified for their radioprotective action and compiled in the present study. Conclusion: As various studies have indicated the harmful effects of ionizing radiations on normal cells, to reduce these effects radioprotective agents are used before or after exposure to radiations. Compounds derived from natural sources are proved to have few side effects and they possess radioprotective property due to the presence of alkaloids, resins, volatile oils, tannins in their molecular structure. Various plants having such radioprotective constitutes have been identified for their radioprotective action and compiled in the present study.

CpG-Oligodeoxynucleotides Improved Irradiation-Induced Injuries by G-CSF and IL-6 Up-Regulation

Background/Aims: This study investigated the radioprotective properties of three classes of CpG-oligodeoxynucleotides (CpG-ODNs) and the underlying mechanisms. Methods: Mice irradiated at different doses(7Gy or 9Gy) were treated with or without ODNs(50μg via intraperitoneal injection). Assays were performed to determine survival rate and the number of white blood cell in peripheral blood. The levels of granulocyte-colony stimulating factor(G-CSF), interleukin 6(IL-6) and interferon-α (IFN-α) were measured using enzyme-linked immunosorbent assay (ELISA). Results: Survival rate of mice irradiated in 7Gy was increased from 50% to about 100% with ODNs pretreatment. ODNs administration increased the number of WBCs of irradiated mice. G-CSF, IL-6 and IFN-α levels were up-regulated with ODNs treatment. Conclusion: All three classes of ODNs protected mice from irradiation-induced injuries. B-class ODNs exhibited the most potent radioprotective property via the up-regulation of G-CSF and IL-6.

A STUDY ON THE RADIOPROTECTIVE PROPERTY OF THIOUREA AGAINST RADIATION-INDUCED CHROMOSOME DAMAGE

The protective ability of thiourea in five different concentrations ranging from 5 × 10−2M to 1 × 10−5M has been demonstrated on chromosome aberrations in root tips of Allium cepa exposed to 350r X-irradiation. It was shown that protection against radiation-induced chromosome fragments and anaphase bridges was attained when the germinating seeds had been treated with thiourea for 1 hour prior to irradiation.