Radioprotective effect of Terminalia Chebula Retzius extract against γ-irradiation-induced oxidative stress

The present study was undertaken to evaluate the radioprotective effect of Terminalia chebula Retzius extract against γ-irradiation-induced oxidative stress in rats. Major phenolic compounds such as total phenolics, flavonoids and triterpenoids contents of Terminalia chebula extract (TCE) were measured. Potential antioxidant activity of TCE was tested by free radical scavenging activity (FRSA) using 1,1,2,2-diphenyl-p-picryl hydrazyl (DPPH), total antioxidant power (TAP) using ferric reducing antioxidant power (FRAP), metal chelating activity (MCA) and inhibition of DNA damage of plasmid (pBR322). In vitro studies showed that TCE possesses potential antioxidant activity and protected plasmid DNA against breakage induced by Fenton reactants. Endogenous spleen colony forming unit (CFU) assay, DNA damage using rat peripheral blood by single cell gel electrophoresis (comet assay) and intestinal histopathological studies in rats were performed in order to find the radioprotective effect of TCE. Animals were divided into various groups and pretreated with TCE (80 mg/kg body weight, i.p.) for 5 days prior to whole body γ-irradiation. The results showed that TCE administration prior to γ-irradiation significantly enhanced the CFU counts, reduced radiation-induced cellular DNA damage and gastrointestinal cell death. The results suggested that TCE is able to protect from γ-irradiation-induced oxidative stress and may considered as probable radioprotector.