Rosmarinic acid attenuates D-galactose induced behavior impairment in mice and its mechanism

The aim is to study the protective effects of Rosmarinic acid (RosA),on age-related behavior in senescent mice induced by consecutive injection of D-galactose (D-gal) and to explore in-brain mechanism of its effects. In the present study, Female BALB/c mice randomly divided into the control group, model group and 3 doses of RosA treatment groups, and the oral administration of RosA (100 mg/kg, 200 mg/kg, 400 mg/kg) started with subcutaneous injection of D-gal (100 mg/kg). Two behavior models, passive avoidance test and beam walking task, were used to research the process of learning-memory and Sensorimotor activity. The results showed that mice treated with RosA could significantly increased the step-down latency and decreased the number of mitakes in passive avoidance test compared with the mice of the model group, and increased balance time and decreased the struggle time in beam walking test remarkably, too. In addition, there was a significant increase in the activities of superoxide dismutase (SOD) and catalase (CAT), and decrease in the contents of malondialdehyde (MDA) in brain of RosA-treated mice. So the improvement of the antioxidase activity of brain in the aging mice may be one of the reasons of RosA could improve the age-related behavior dysfunction produced by D-gal.