Potential Antidepressant-Like Activity of Rhus coriaria L (Sumac) Ethanolic Extract: The Mechanism of Action via the Monoaminergic System in a Mouse Model

Background: Studies have reported certain side effects that occur with the use of conventional antidepressants limit their clinical use. Plant derivatives such as Rhus coriaria L extract can be used as alternatives for depression. Objectives: This study was designed to investigate the antidepressant-like effects of R. coriaria in a mouse model and the role of the monoaminergic system in its mechanism of action. Methods: A total of 174 male NMRI mice were used. Thirty minutes after treating animals with common antidepressants and R. coriaria extract (25 - 200 mg/kg), the tail suspension test (TST) was performed. One hour after treating mice with serotonergic, adrenergic, and dopaminergic antagonists, 100 mg/kg of the extract was administered, and TST was performed after 30 minutes. Potential synergistic interactions between the extract and the sub-doses of fluoxetine (Flx) and imipramine (Imp) were also investigated. Injections were all administered intraperitoneally. Results: Rhus coriaria extract (50 - 200 mg/kg) induced antidepressant-like effects (P < 0.001) without altering animal locomotion in the open field test (OFT; P > 0.05). The tail suspension test showed that the antidepressant-like activity of the extract was blocked by pretreating with the above-mentioned antagonists (P < 0.05 and P < 0.01, respectively). The sub-dose of the extract also increased the efficiency of the sub-doses of common antidepressants (P < 0.001). Conclusions: The extract showed antidepressant-like activity via the monoaminergic system and increased the efficiency of common antidepressants. We suggest adding dried R. coriaria extract powder to the formulation of common antidepressant agents following thorough clinical studies on the substance.