Radioprotective Effects of Hairy Roots of Ginseng

Panax ginseng is an important medicinal plant in Korea, which has broad efficacious effects against hypertension, diabetes, nociception and cancer. And it improves weakness. The native ginseng is a slow growing plant taking 5-7 years from seed planting to mature root harvesting, during which time much care is needed since its growth is susceptible to many environmental factors such as soil, shade, climate, pathogens and pests. Nowadays, a wild ginseng has become extremely scarce and the ginseng supply depends almost exclusively on field cultivation, which is a time-consuming and labor-intensive process. To meet the demand for the plant in the international market, a bioreactor technology is a useful tool for production of root biomass on a large scale. Therefore, suspension culture of ginseng roots in bioreactors is viewed as a primary alternative method for large-scale production and recently our laboratory has developed a protocol for the in vitro culture of P. ginseng. About 60-70% of cellular DNA damage produced by ionizing radiation is caused by OH, formed from the radiolysis of water. Oxidative stress occurs when there is an excessive free radical production and/or low antioxidant defense, and results in the chemical alterations of biomolecules causing structural and functional modifications. The generation of the reactive oxygen metabolites plays an important role in the pathogenesis of the irradiation-induced tissue injury. An extensive literature review implicates cellular DNA as the primary target for the biological and lethal effects of ionizing radiation. Besides DNA, lipids and proteins are also attacked by free radicals. The purpose of this study, aimed at investigating the possible radioprotective effect of the hairy roots of P. ginseng on irradiation-induced damage by the comet assay