The impairment to the healthy brain tissue is a crucial factor limiting the application of radiation therapy in patients with nervous system neoplasms. Teucrium polium (TP) L. (family Lamiaceae), a wild-growing flowering plant, has beneficial curative properties. The flavonoids of TP have many valuable biological activities. This study aims atinvestigating the
ameliorative effect of TP extract on γ-radiation toxicity in brain of albino rats. Thirty adult male albino rats were used. Ionizing irradiation was performed by whole body exposure of rats to 8Gy. TP was administered by intragastric tube in a dose of 200mg/kg body weight. Animals were divided into five groups: Group I (control), Group II (TP), Group III (γ-irradiated), Group IV (TP+γ-irradiated) and Group V (TP+γ-irradiated+TP). The action of TP extract was investigated after one week post irradiation by measuring serum liver and renal functions, and oxidative stress parameters in brain tissue. Moreover, serum S100B and brain-derived neurotrophic factor (BDNF) in brain tissue were measured, in addition to
histopathological examination. TP at a dose of 200mg/kg body weight did not have hepatotoxic or nephrotoxic effects.
TP extract significantly ameliorated γ-radiation-induced brain damage by improving radiationinduced oxidative stress. The role of the extract was confirmed by improvement of the levels of S100B in the serum and BDNF in the brain as well as amelioration of histopathological changes induced by radiation. The administration of TP before and after irradiation was more effective than administration only before irradiation. These results revealed that the administration of TP extract might ameliorate γ-radiation-induced brain injury by the attenuation of oxidative stress, the regulation of BDNF and the suppression of S100B.