Tannins from Terminalia chebula Terminalia chebula fruits attenuates GABA antagonist‐induced anxiety‐like behaviour via via modulation of neurotransmitters

摘要

Abstract Objectives This article investigates the anxiolytic activity of Terminalia chebula tannin‐rich extract against picrotoxin (PTX; GABA antagonist)‐induced anxiety in mice model. Methods Anxiolytic activity was studied by elevated plus maze (EPM), open field test (OFT), light/dark box test (LDT) and Vogel's conflict test (VCT). Electroencephalogram (EEG) was performed to know the changes in brain activity instigated by GABA antagonist. 5‐hydroxytryptamine (5‐HT), dopamine and norepinephrine levels in brain tissues were estimated by HPLC. The mRNA (CREB, BDNF, GABA, and 5‐HT 1A ) and protein expression (CREB, p‐CREB, BDNF, ERK ?, p‐ERK ?, GABA A Rα1, 5‐HT 1A and GAPDH) levels in brain tissue were determined by RT‐PCR and Western blot analysis, respectively. Key findings Terminalia chebula tannin‐rich extract (TCHE) supplementation increased locomotion in mice towards open arm (EPM), time spent in illuminated area (LDT), rearing frequency (OFT) and number of shocks (VCT) compared to PTX ( P? ? 0.05). Furthermore, TCHE down‐regulated serum cortisol levels and showed increased levels of 5‐HT, DA and NE. Gene expressions such as BDNF, CREB, GABA A and 5‐HT 1A were up‐regulated by TCHE treatment compared to PTX. Conclusions Terminalia chebula tannin‐rich extract showed significant anxiolytic activity against picrotoxin and could be used as natural therapy in neurodegenerative disorders.