Ease effect of ginsenoside on different-intensity ionizing radiation damage to human hematopoietic stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND:Many domestic and foreign scholars and institutions are studying how to relieve radiation damage and to find the most suitable drug, while ginsenosides as the main pharmacological ingredient of ginseng show significant antioxidant effect. OBJECTIVE:To investigate the ease effect of ginsenosides on human hematopoietic stem cels under different intensities of ionizing radiations. METHODS: The CD34+ hematopoietic stem cels were isolated from the healthy cord blood. Then the cels were divided into normal group and ginsenoside-pretreated group, respectively, exposed under 1, 2, 5 Gy of X-ray irradiations for 24 hours. Cel viability was detected in irradiated hematopoietic stem cels by MTT assay. Apoptosis was estimated using the folowing assays Annexin-V assay, caspase-3 mRNA and protein levels. The generation of reactive oxygen species was evaluated, in the presence or absence of ginsenoside in liquid cultures of CD34+ human hematopoietic stem cels irradiated with 1-, 2- and 5-Gy X-rays, using a flow cytometry assay. The Nrf-2 mRNA and protein levels were also studied by western blot analysis and RT-PCR, respectively. RESULTS AND CONCLUSION: Ionizing radiation at the therapeutic dose could decrease the viability of CD34+ cels and induce the cel apoptosis, and meanwhile, the activity of intracelular reactive oxygen species also showed a progressive increase that was correlated with the dose of ionizing radiation. However, ginsenoside pretreatment could relieve these above-mentioned effects. Ginsenoside inhibited the increase in caspase-3 activity induced by ionizing radiation, and additionaly, enhanced the mRNA and protein expressions of Nrf-2 in CD34+cels. In conclusion, ginsenoside protects CD34+ hematopoietic stem cels from radiation effects, which is probably correlated with anti-apoptosis and anti-oxidant roles of ginsenosides.