Effects of hydroalcoholic extract of Propolis on oxidative stress indices of rat fetal brain induced by chronic prenatal stress

Prenatal stresses have different effects on structural features and antioxidant system in the fetus and build up disturbances in the hypothalamus-pituitary-adrenalaxis. Propolis is known as one of the strongest natural antioxidants. The purpose of this study was to investigate the effects of hydroalcoholic extract of Propolis on indices of oxidative stress induced by prenatal stress in the rat fetal brain. Pregnant female Wistar rats were divided into 6 groups: Control, stress+Propolis solvent, non-stress +Propolis solvent, stress +Propolis 50 mg/kg, stress + Propolis 100 mg/kg and stress + Propolis 200 mg/kg. In the third to sixth groups, stress was created by restrainer for 6 hours per day from day 12 to day 20 of gestation in the rats. Then, the blood corticosterone and malondialdehyde (MDA), ferric ion reducing antioxidant power (FRAP), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels in brain were measured on day 21 of pregnancy. Chronic prenatal stress significantly increased blood corticosterone levels and MDA, whileas, reduced the levels of FRAP, SOD and GPx in the brain tissue of 21 days old embryos. Treatment of pregnant rats under chronic stress with extract of Iranian Propolis significantly reduced corticosterone levels in blood and brain's MDA and also increased FRAP, SOD and GPx in the brain tissue from fetuses. Our findings showed that Iranian Propolis prevents from increasing serum corticostrone and brain MDA levels and from decreasing FRAP, SOD and GPx levels in brain under prenatal stress.