Investigating the Antidepressant and Antioxidant Activity of the Alcoholic Extract of Melilotus Officinalis L. in Male Rats

Background Depression is one of the most common psychological disorders that can affect a person’s mood and change his/her perception of the self and environment. Melilotus officinalis L. plant contains effective substances and antioxidant compounds. Objective The present study aims to investigate the antidepressant effects of alcoholic extract of Melilotus officinalis L. in male rats. Methods In this experimental research, 42 male rats were divided into six groups of 7 including control (normal saline), negative control (reserpine), positive control (reserpine+fluoxetine) and three reserpine groups treated by intraperitoneal injection of 100, 200, 400 mg/kg doses of alcoholic extract of Melilotus officinalis L. Behavioral tests including forced swim test (FST) and tail suspension test (TST) were used to evaluate depression, and the antioxidant capacity and malondialdehyde level were also measured. The data were analyzed in SPSS software, version 20 using one-way analysis of variance. The significance level was set at P<0.05. Results The 200 mg/kg and 400 mg/kg doses of alcoholic extract significantly reduced the duration of immobility in the FST compared to the negative control. In the TST, the doses of 200 and 400 mg/kg showed a significant increase compared to the negative control. The doses of 200 and 400 mg/kg significantly increased the antioxidant capacity of the brain compared to the negative control. The doses of 200 and 400 mg/kg significantly reduced the antioxidant capacity of the brain compared to the negative control. Conclusion The alcoholic extract of Melilotus officinalis L has antidepressant effects similar to fluoxetine probably due to its antioxidant compounds.