Hydroethanolic extract of Carthamus tinctorius induces antidepressant-like effects: modulation by dopaminergic and serotonergic systems in tail suspension test in mice

Abstract

<strong><em>Objective(s)</em></strong>: Studies indicate that major deficiency in the levels of monoaminergic transmitters is a reason for severe depression. On the other hand, it is shown that <em>Carthamus tinctorius</em> L. (CT) may improve neuropsychological injuries by regulation of the monoamine transporter action. Hence, the present study was undertaken to evaluate the involvement of monoaminergic systems in antidepressant-like effect of CT extract in the tail suspension test (TST) in mice.<br /> <strong><em>Materials and Methods: </em></strong>The mice were intraperitoneally (IP) treated with CT extract (100–400 mg/kg) 1hr before the TST. To investigate the involvement of monoaminergic systems in antidepressant-like effect, the mice were treated with receptor antagonists 15 min before CT extract treatment (400 mg/kg, IP) and 1hr before the TST.<br /> <strong><em>Results:</em></strong> Findings showed that CT extract (100–400 mg/kg, IP), dose-dependently induced antidepressant-like effect (<em>P</em><0.001), but it was not accompanied by alterations in spontaneous locomotor activity in the open-field test. Pretreatment of mice with SCH23390, sulpiride, haloperidol, WAY100135, cyproheptadine, ketanserin and p-chlorophenylalanine (PCPA) inhibited the antidepressant-like effect of CT extract (400 mg/kg, IP), but not with prazosin and yohimbine. Co-administration of CT extract (100 mg/kg, IP) with sub-effective doses of fluoxetine (5 mg/kg, IP) or imipramine (5 mg/kg, IP) increased their antidepressant-like response.<br /> <strong><em>Conclusion:</em></strong> Our findings firstly showed that components (especially N-Hexadecanoic acid) of CT extract induce antidepressant-like effects by interaction with dopaminergic (D1 and D2) and serotonergic (5HT1A, 5-HT2A receptors) systems. These findings validate the folk use of CT extract for the management of depression.