The role of allopregnanolone in the anxiolytic-like effect of free and easy wanderer plus (FEWP), a polyherbal preparation

Anxiety disorders are the serious and burdensome psychiatric illnesses, which are closely correlated with allopregnanolone. The down-regulation of allopregnanolone biosynthesis has been implicated as the possible contributor to the aetiology of anxiety disorders. Free and easy wanderer plus (FEWP) is a well-known traditional Chinese medicine that had been shown to be effective in various mood disorders. The purpose of the present study was to evaluate the anxiolytic-like effect of FEWP and its association with the level of allopregnanolone in the brain. The animal behavioral tests were processed by the acute FEWP (2.5, 5 and 10 mg/kg, p.o.) treatment. It had been shown that FEWP produced anxiolytic-like effects in behavioral models, including novelty suppressed feeding (5, 10 mg/kg, p.o.), Vogel-type conflict test (10 mg/kg, p.o.), elevated plus-maze test (5, 10 mg/kg, p.o.). The animals were decapitated after the end of the behavioral tests and measured the allopregnanolone level of the prefrontal cortex and hippocampus by enzyme-linked immunosorbent assay (ELISA). The allopregnanolone level of the prefrontal cortex and hippocampus was increased by administration of FEWP (5, 10 mg/kg, p.o.). Overall, these results indicated that FEWP exerts anxiolytic-like effects that were associated with the stiumlation of the allopregnanolone biosynthesis.