Anxiolytic effects of an aqueous extract of Crassocephalum bauchiense Hutch (Asteraceae) in mice with possible GABAergic involvement

Background and Objective: Crassocephalum bauchiense Hutch is a species of flowering plant from the Asteraceae family. It’s used in traditional medicine for the treatment of brain disorders including epilepsy, depression and anxiety. This study evaluated the anxiolytic effects of Crassocephalum bauchiense aqueous extract and its possible mechanism of action. Materials and Methods: The aqueous extract of Crassocephalum bauchiense (25, 50, 100 and 200 mg/kg) were administered orally to mice one hour before the behavioural testing. Elevated plus maze and open field tests were used, respectively for detecting it anxiolytic properties. Immediately after the open field test, animals were sacrificed and the brain GABA content, and the activities of GAD and GABA-T were measured. Results: Crassocephalum bauchiense (100 and 200 mg/kg) significantly increased the number of entries into, percentage of entries into, and percentage of time in open arms, and reduced rearing, head dipping, and the percentage of time in closed arms, in the elevated plus maze. The plant extract significantly increased crossing and reduced rearing and defecation, in the open field test. In biochemical experiments, the concentration of GABA and the activity of GAD were increased; while the GABA-T activity was decreased, respectively, in the brain of Crassocephalum bauchiense treated-mice. Conclusion: These results suggest that Crassocephalum bauchiense aqueous extract possess anxiolytic properties in the models employed. The extract might potentially act by GABAergic activation in the central nervous system. These data justify and explain the use of Crassocephalum bauchiense to treat anxiety empirically in traditional medicine.