The effects of ellagic acid on brain derived neurotrophic factor levels in mouse depression models

Objective: The aim of present study was to evaluate the antidepressant-like activity of ellagic acid (EA) in mice. For understanding underlying mechanisms, the possible role of brain derived neurotrophic factor (BDNF) in EA's antidepressant-like effect was also investigated. Method: Male balb/c mice weighing 25-30 gr were used for the study. Animals were divided into 5 groups (n:10): vehicle (0,1ml/day), sertraline (5 mg/kg), EA (1-2,5-5 mg/kg) and drugs were daily injected by intraperitoneal route during 14 days. Locomotor activity was measured by open field test. Tail Suspension Test (TST) and Forced Swim Test (FST) were conducted to mice as depression models. After behavioural tests each mice was sacrified by cervical dislocation to obtain samples for western blot analysis. Results: All three doses of EA and sertraline did not significantly affect the spontaneous locomotor activity of mice compared to vehicle group. EA in three different doses produced statistically significant decrease in immobility time as compared to vehicle group in TST. EA at 1 and 5 mg/kg doses did not produce any significant effect in immobility time as compared to vehicle group in FST. But EA produced significantly reduced immobility time at 2,5 mg/kg dose. EA treatment increased hippocampal BDNF levels in mice compared to vehicle group. Conclusion: The present study demonstrates that EA is able to produce antidepressant-like effect in mice which is not due to an increase in the locomotor activity. Moreover the antidepressant-like effects of EA seems to be mediated by increased BDNF levels in mice hippocampus.