Possible ameliorative effect of aqueous extract of date (Phoenix dactylifera) pits in rats exposed to gamma radiation

Purpose: To evaluate the radioprotective efficacy of date (Phoenix dactylifera) pits extract (DPE) against gamma-irradiation-induced liver damage in the male albino rats. For this study, 30-day survival, dose reduction factor (DRF), antioxidant status and some biochemical changes in the serum and hepatic tissue were evaluated. Materials and methods: To calculate 30-day survival, median lethal dose of 30 days (LD50/30) and DRF, DPE was orally administered to rats for 21 days before irradiation with different doses (5, 6, 8, 10 and 12Gy) of gamma-rays and the rats were observed for 30 days post-irradiation. To evaluate the radioprotective efficacy of DPE against gamma-irradiation induced-liver tissue damage, animals were divided into four groups (eight animals in each group). (i) Control: rats not subjected to any treatment; (ii) DPE: DPE was orally administrated (1000mg/kg body weight) for 21 days; (iii) RAD: rats ' whole body exposed to 5Gy of gamma-rays; (iv) DPE+RAD: rats received DPE treatment for 21 days before gamma-irradiation. Animals were sacrificed on the seventh day postexposure to radiation. Results: The results showed that pretreatment prior to irradiation with DPE resulted in a significantly higher 30-day survival rate of rats after exposure to different doses of gamma-irradiation. Furthermore, DPE treatment resulted in a significant improvement in the hepatic redox state, manifested by a marked increase of superoxide dismutase (SOD) and catalase (CAT) activities and glutathione content associated with a significant decrease of malondialdehyde (MDA) level. In addition, DPE exhibited hepatoprotective effect evidenced by a marked increase in serum levels of insulin, testosterone, high-density lipoprotein-cholesterol (HDL-c) and hepatic glucose 6 phosphate dehydrogenase (G6PHD) activity associated with a significant decrease in serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (gamma-GT), glucose, total cholesterol (TC), triglycerides (TG), low density-lipoprotein cholesterol (LDL-c) and hepatic glucose 6 phosphatase (G6Pase) activity, compared with irradiated group. Moreover, DPE showed positive modulation in the levels of hepatic metals [(iron (Fe), zinc (Zn), copper (Cu) and manganese (Mn)]. Conclusions: DPE treatment prior to gamma irradiation produced biochemical changes that could lead to a reduction in radiation-induced oxidative stress. Hence, we suggest that DPE may be useful as a new natural radioprotective agent.