Anxiolytic and anti-depressant effects of hydroalcoholic extract from Erythrina variegata and its possible mechanism of action

BACKGROUND: Erythrina variegata has been widely used as a traditional medicine. OBJECTIVE: The study was designed to evaluate the anxiolytic and anti-depressant effects of an extract from Erythrina variegata. METHODS: The extract was evaluated for anxiolytic and anti-depressant action using the elevated plus maze, light/dark box, open field, forced swimming and tail suspension tests in mice. The mechanism of action was further elucidated using high-performance liquid chromatography with fluorescence detection methods to assay the levels of five neurotransmitters in brain. RESULTS: The extract exhibited significant increase in the percentage of the open arms entries and the time spent in the open arms in the elevated plus maze test. The results of the light/dark box test revealed a significant increase in the amount of time spent in the light chamber. Extract- treated mice also produced significant increase in the number of crossings and rearings in the open field test. In the forced swimming and tail suspension tests, the extract was able to promote significant decrease in the immobility time. In addition, the extract significantly altered the levels of five neurotransmitters in the brain tissue. CONCLUSION: These findings suggest that Erythrina variegata presents potential anxiolytic and anti-depressant activity, and the mechanism may be related to the alteration of neurotransmitter levels.