|Description||Backgroundâ Ionizing radiation (IR) initiates intracellular oxidative stress through enhanced
formation of reactive oxygen species (ROS) that attack DNA leading to cell death. As the diversity
of IR applied in medicine, agriculture, industry, and the growing threats of global terrorism, the
acquisition of radioprotectors is an urgent need for the nation. However, the applicability of
radioprotectors currently under investigation is limited due to their inherent toxicity.
Objectiveâ This study investigated the effect of a standardized North American ginseng extract
(NAGE, total ginsenoside content: 11.7%) on DNA damage in human lymphocytes at 90 min postirradiation.
Designâ With the application of NAGE (250 â 1000 Î¼g mlâ 1) at 90 min post-irradiation (1 and 2
Gy), DNA damage in lymphocytes obtained from 40 healthy individuals was evaluated by
cytokinesis-block micronucleus (CBMN) assay. Similar experiments were also performed in
lymphocytes treated with WR-1065 (1 mM or 3mM). In addition, before and after irradiation,
lymphocytes obtained from 10 individuals were measured for their total antioxidant capacity (TAC)
and the reactive oxygen species (ROS).
Resultsâ The significant effect of NAGE against 137Cs-induced MN in lymphocytes is
concentration-dependent. NAGE (750 Î¼g mlâ 1) reduced MN yield by 50.7% after 1 Gy and 35.9%
after 2 Gy exposures, respectively; these results were comparable to that of WR-1065. Further, we
also found that NAGE reduces MN yield and ROS but increases TAC in lymphocytes.
Conclusionsâ Our results suggest that NAGE is a relatively non-toxic natural compound that
holds radioprotective potential in human lymphocytes even when applied at 90 min post-irradiation.
One of the radioprotective mechanisms may be mediated through the scavenging of free radicals and
enhancement of the intracellular TAC. Originally published Journal of Alternative and Complementary Medicine Vol. 16, No. 5 2010.||en_US