An Insight Into the Anxiolytic Effects of Lignans (Phyllanthin and Hypophyllanthin) and Tannin (Corilagin) Rich Extracts of Phyllanthus amarus : An In-Silico and In-vivo approaches

Abstract

Background: This investigation was aimed to explore the anxiolytic potential of Phyllanthus amarus standardized extracts and predict probable role of marker phyto constitutents. Objective and Methods: Three standardized extracts of Phyllanthus amarus plant viz. standardized aqueous extract of Phyllanthus amarus whole plant (PAAE), standardized methanolic extract of P. amarus leaf (PAME) and the standardized hydro-methanolic extract of P. amarus leaf (PAHME) were tested in the classical animal models of anxiety vise: Elevated plus-maze model and Light & Dark Exploration test. Results: The lower doses of the tannin rich extract (PAHME) of the P. amarus possess significant anxiolytic activity compared to lignin rich (PAME) and aqueous extracts (PAAE), while at a higher dose (400mg/kg) the results of all three extracts appears to be potentially sedative. While the molecular docking studies support these probable anxiolytic and sedative effects of the Phyllanthus amarus extracts could be due to the interaction of tannins and lignans with the GABA-benzodiazepine receptor complex. Conclusion: The results of the present study indicate that the tannin-rich extract of the P. amarus may have potential clinical applications in the management of anxiety. It can be further studied for optimum dosage to be used as a future of anti-anxiety drug development or as a standardized Phytomedicine.

Identification of Anxiolytic Potential of Niranthin: In-vivo and Computational Investigations

“…Henceforth, our present study has been focused to carry out anti-anxiety activity of pure, isolated and characterized niranthin in various animal models in-vivo as assessed by light/dark box, EPMT and motor coordination test [25][26][27][28]. We have also carried out in-silico molecular modelling studies in order to support our current findings [22,24,[29][30][31][32][33][34][35][36]. Molecular docking simulations used in our current study will also shade more lights on GABA assisted/mediated role of niranthin as anti-anxiety agent.…”

“…We have recorded for the duration of 5 min, the number of crossings and time spent in L & D compartments, after individually placing naïve mice in the center of the L compartment [22,24].…”

“…The systematic search method was utilized for generation of the conformers. We have ranked the docking results according to the decrements in docking energies of the different possible conformers for each of the ligands [22,24].…”

“…Molecular docking studies were performed using Vlife MDS 4.6.1 version. In recent studies, varied targets were screened for biological activities, which formed the basis for present molecular screening methodology [22,24,[29][30][31][32][33][34][35][36]. 3D X-ray crystallographic structure of the GABA-(A) homopentamer receptor (PDB Code: 4COF) was retrieved from the Protein Data Bank (www.rcsb.com) [37].…”

“…Recently, our analysis for P.amarus and P. fraternus standardized extracts showed antxiolytic potential in mice models. In order to shade more lights on these activities, we carried out analysis with single, isolated niranthin molecule [22][23][24].…”