Background: Phyllanthus fraternus Webster Linn (family, Euphorbiaceae) is used as a traditional medication for
the treatment of various disorders and has therapeutic implications.
Objective: This investigation intends investigation of the anxiolytic potential of Phyllanthus fraternus standardized extract
and prediction of probable role of its marker phyto-constituents.
Methods: We have tested the standardized hydro-ethanolic extract of Phyllanthus fraternus (whole plant) for Elevated plusmaze
model (EPM) and Light & Dark Exploration test as classical models for anxiety. Phyto-chemical HPTLC fingerprint
analysis was performed for detection of two classes of compounds lignans and tannins. HPTLC analysis of standardized extract
was performed using Phyllanthin Hypophyllanthin and Corilagin as marker compounds. Additionally, GABA receptor
antagonism was studied in other sets of experiments to assess the involvement of this receptor in the anxiolytic-like effects
produced by Phyllanthus fraternus.
Results: The lower doses of the lignan and tannin-rich extract of the Phyllanthus fraternus possess significant anxiolyticlike
activity compared to the standard diazepam. Additionally, the results of the present study suggested that high doses
(400mg/kg) of Phyllanthus fraternus have exerted some sedative-like effects. Phytochemical screening and HPTLC fingerprint
analysis indicate the presence of lignans and tannins, whereas HPLC analysis of the standardized extract revealed the
presence of marker lignan (Hypophyllanthin) and Tannin (Corilagin). The anxiolytic-like effect of Phyllanthus fraternus observed
in the mice models were blocked by Flumazenil indicating the involvement of GABAA receptors in the modulation
of this effect. Our molecular docking studies also supported probable anxiolytic and sedative effects.
Conclusion: To summarize results support the use of Phyllanthus fraternus in the anxiety-like symptoms/disease condition
and suggest its anxiolytic-like effect governed by the GABA-A receptors.