Abstract
In this study, the anxiolytic activity of Piper nigrum essential oil (PNEO) was evaluated in the elevated plus maze (EPM) and the antidepressant-like effect was evaluated through tail suspension test (TST) in mice. Flumazenil, a competitive inhibitor of GABAA receptor in the benzodiazepine site and WAY-100635 maleate salt, a 5-HT1A receptor antagonist were used to find out the possible mechanism(s) of action of PNEO. To exclude the false-positive results due to the enhancement of the locomotor activity, the animals were submitted to open field test (OFT). We also measured monoamines levels of the mice brain after acute PNEO treatment. The data obtained from the study suggest that the anxiolytics and antidepressant-like effect of PNEO have observed in EPM and TST respectively in a dose-dependent manner after oral acute and repetitive treatment. WAY-100635, but not flumazenil was able to reverse the effect of PNEO in EPM and TST both, indicating the possible involvement of 5-HT1A receptor. The neurochemical analysis showed no alteration in monoamine levels in mice brains. Furthermore, no locomotor impairment or sign of toxicity or changes in body weight or abnormalities in the biochemical parameters, except for a significant decrease in total cholesterol level was observed after treatment with PNEO. The findings suggest that Piper nigrum EO possesses a dual anxiolytic and antidepressant-like effect through the possible involvement of serotonergic transmission.
Highlights
Anxiety is the most frequent neuropsychiatric disorder that affects anyone at all age groups
For the extraction of essential oils from fruits of Piper nigrum, powdered material was hydrodistilled for 4 h in a Clevenger type of apparatus to yield 1.4% transparent essential oil (PNEO) with a characteristic odor
This study aimed to establish the anxiolytic and antidepressant-like effect of essential oils obtained from fruits of Piper nigrum through open field, elevated plus maze and tail suspension test
Summary
Anxiety is the most frequent neuropsychiatric disorder that affects anyone at all age groups. Recent evidences suggested that antidepressant drugs are more effective in the treatment of anxiety disorders via two major biochemical pathways namely, central serotonergic system and GABA-BZD receptor complex (Suranyi-Cadotte et al, 1990). There is an urgent requirement for the development of new psychopharmacological agents having a rapid onset of action along with minor adverse effects. In this aspect, aromatic medicinal plants have been increasing their importance as the rich diversity in bioactive agents that have led to the development of important therapeutic agents related to these disorders. Many of them have been reported to treat numerous neurological disorders including anxiety and depression (Diniz et al, 2019; Oliveira Júnior et al, 2018)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
