Evaluation of the Antidepressant Like Activity of Ethanolic Extract of Calendula officinalis using Rodent Models (Wistar Rat) of Depression

Background:Depression disorder has been considered to be the global common psychological CNS disorder affecting about 121 million people worldwide and is among the leading causes of disability that not only inflicts suffering but also carries a high economic burden. Calendula officinalis L. (Marigold) is globally known for its medicinal importance containing various phytochemicals including terpenoids, quinones, coumarins and other constituents, showing some important biological activities like immuno-stimulant, hepatoprotective, antioxidant, etc. activities with no toxic effect.Objective:This study aims to evaluate the antidepressant effect of ethanolic extract of Calendula officinalis using rodent models (Wistar rat) of depression.Material and methods:The present study was carried out to evaluate the antidepressant effect of ethanolic extract of Calendula officinalis in Wistar rat. This effect was determined by recording the immobility time in Forced Swim Test (FST) and a number of squares crossing and rearing in Open Field Test (OFT). The rats were randomly divided into 5 groups. Rats belonged to group 1 act as control group and group 2 were given Imipramine (10 mg/kg, i.p.) which act as standard group.Wistar rats were treated i.p. with Ethanolic extract of Calendula officinalis group 3, 4 and 5 were given 100mg/kg, 200mg/kg and 400mg/kg respectively.Results:The effect of rat model of depression i.e. Forced Swim Test (FST) and Open Field Test (OFT) model indicated that Ethanolic extract of Calendula officinalis showed potent to moderate antidepressant effect (decrease in immobility time and increase in number of square crossing and rearing) as compared to normal group. The drug might act as monoamine oxidase inhibitors.Conclusion:Taken all together, the present study concluded that the drug EECO was to exert antidepressant effects by inhibiting the monoamine oxidase-A (MAO-A) reaction, which is responsible for the regulation of the metabolism of the neurotransmitter 5-hydroxytryptamine (5-HT) in the brain. This drug might act as monoamine oxidase inhibitors (MAO-inhibitors) hence may increase the levels of norepinephrine, dopamine and serotonin; and decrease the levels of GABA in the brain.