The protective role of Ulva lactuca against genotoxic and biochemical effects induced by γ-irradiation in rats

Radiation hazards are considered as one of the most serious challenges that frighteningly threaten our lives. This study aimed toevaluate the antioxidant properties of aqueous and ethanolic extracts of the green alga Ulva lactuca against the different genotoxicand biochemical damage induced by γ-irradiation in rats. The experimental model was divided into 4 groups: group I “control”included the non-irradiated rats, group II “Irradiated group” included rats exposed to 4 Gy(137Cs) whole body γ-irradiation, group IIIcomposed of rats treated with an aqueous extract of U. lactuca 100 mg/kg body weight for 15 days before 4 Gy of γ-irradiation, andfinally group IV included rats treated with the ethanolic extract U. lactuca 100 mg/kg body weight for 15 days before 4 Gy of γ-irradiation. The results revealed that these algal extracts noticeably eliminated the harmful effects of oxidative stress induced byexposure to γ-irradiation through decreasing the produced levels of H2O2 in hepatic tissue. Furthermore, they decreased theincidence of micronucleated PCE in bone marrow cells and apoptotic DNA damage. According to the apoptotic gene expressions, theethanolic extract of U. lactuca appears to be more efficient in down-regulations of apoptotic genes Bax and Caspase-3 than theaqueous one. Total phenolics, flavonoids and sulphated polysaccharides, well-known in order Ulvales, are thought to be the maindrivers responsible for this potent antioxidant defense mechanism. The widely-distributed green alga U. lactuca seems to be apromising antioxidant and anti-apoptotic tool to overcome lethal effects of γ-irradiation.