Chapter 7 - Role of phytoconstituents and their mechanism in attenuation of radiation effects: An update

Abstract

Despite many advantages of ionizing radiation (IR) in medical diagnosis, warfare, research, space, industry, etc., continuous exposure to it is noxious, and the effects caused by it are invisible. Rapid technological advancements have increased exposure to IR, which has been found to be a reason for increased levels of radiation-induced reactive oxygen species (ROS). Increased ROS increases membrane lipid peroxidation, which in turn causes DNA damage, and finally leads to cell death. In this chapter, we initially discussed the effects of IR and the need for identification of radioprotectors. Chemical radioprotectors like WR-2721 (amifostine), CBLB502, Tempol, monoclonal antibodies like cetuximab, and bevacizumab were available in the market, of which amifostine offers good radioprotection, was initiated by U.S. Department of Defense, and is clinically approved by the Food and Drug Administration (FDA). However, due to its side effects, toxicity, and high cost, research has been focused and the efforts have been made on medicinal plants to discover a potent radioprotectant that is affordable and non-toxic. Effects of IR on different organs of the human body were also clearly mentioned. In vitro and in vivo studies of several medicinal plants and the signaling pathways they trigger for radioprotection were discussed. Together, this data will be helpful to explore a safe and efficient compound that fits as a radioprotectant as well as an alternative to the lethal chemical-based drugs, thus, helping mankind to protect themselves from radiation-induced alterations.