Antidepressant and anxiolytic properties of the methanolic extract of Momordica charantia Linn (Cucurbitaceae) and its mechanism of action.
BACKGROUND
The whole plant of Momordica charantia Linn (Cucurbitaceae) is used in traditional African medicine in the management of depressive illness.


METHODS
Momordica charantia (MC) (50-400 mg/kg, p.o.) was administered 1 h before behavioural studies using the forced swimming test (FST) and tail suspension test (TST) to investigate antidepressant-like effect while the anxiolytic-like effect was evaluated with elevated plus maze test (EPM), hole-board test (HBT), and light-dark test (LDT).


RESULTS
Acute treatment with MC (50-400 mg/kg) significantly increased swimming time (86.51%) and reduced the duration of immobility (52.35%) in FST and TST with peak effects observed at 200 mg/kg, respectively, in comparison to control. The pretreatment of mice with either sulpiride (dopamine D2 receptor antagonist), or metergoline (5-HT2 receptor antagonist), or cyproheptadine (5-HT2 receptor antagonist), or prazosin (α1-adrenoceptor antagonist), or yohimbine (α2-adrenoceptor antagonist), and atropine (muscarinic cholinergic receptor antagonist) 15 min before oral administration of MC (200 mg/kg) significantly blocked its anti-immobility effect. Similarly, MC (200 mg/kg) significantly reduced anxiety by increasing the open arm exploration (64.27%) in EPM, number of head-dips in HBT (34.38%), and time spent in light compartment (29.38%) in the LDT. However, pretreatment with flumazenil (GABAA receptor antagonist) 15 min before MC (200 mg/kg) significantly blocked (54.76%) its anxiolytic effect.


CONCLUSIONS
The findings in this study showed that MC possesses antidepressant-like effect that is dependent on the serotonergic (5-HT2 receptor), noradrenergic (α1- and α2-adrenoceptors), dopaminergic (D2 receptor), and muscarinic cholinergic systems and an anxiolytic-like effect that might involve an action on benzodiazepine-type receptor.
Department of Pharmacology, Therapeutics and Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria.
I O
IO
Ishola
Department of Pharmacology, Therapeutics and Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria.
A A
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Akinyede
Department of Pharmacology, Therapeutics and Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria.
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Sholarin
D000818:Animals; D014151:Anti-Anxiety Agents / Q000737:chemistry / Q000494:pharmacology*; D000928:Antidepressive Agents / Q000737:chemistry / Q000494:pharmacology*; D019662:Cucurbitaceae / Q000737:chemistry*; D003863:Depression / Q000188:drug therapy; D019417:Hindlimb Suspension / Q000379:methods; D008297:Male; D000432:Methanol / Q000737:chemistry; D051379:Mice; D029777:Momordica charantia / Q000737:chemistry*; D009043:Motor Activity / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D013550:Swimming
D014151:Anti-Anxiety Agents; D000928:Antidepressive Agents; D010936:Plant Extracts; D000432:Methanol