Antidepressant-like effects of total saikosaponins of Bupleurum yinchowense in mice

Abstract

Bupleurum is known traditionally to effectively treat depressive-like disorders in East Asia. Pharmacological studies have been carried out on several species of Bupleurum, such asBupleurum chinense DC. and Bupleurum falcatum L. Bupleurum yinchowense, the same genus of Bupleurum R. H. Shan and Yin Li, is abundantly distributed in the Northwest of China and is widely used in folk medicine, but few reports explore its antidepressant-like activities. In the present study, it was observed that the total saikosaponins isolated from B. yinchowense (75 and 150 mg/kg) significantly reduced the immobility time in the forced swim and tail suspension test in mice after 7-day treatment. In the chronic mild stress model, chronic treatment with the total saikosaponins isolated from B. yinchowense (50 and 100 mg/kg) increased the sucrose intake in the sucrose preference test and decreased the latency to feed in the novelty-suppressed feeding (NSF) test. In addition, the total saikosaponins isolated from B. yinchowense augmented the diminished monoamine neurotransmitter concentrations (5-HT, DA and NE) in the prefrontal cortex induced by chronic mild stress. Taken together, our results suggest that the total saikosaponins isolated from B. yinchowense exerts an antidepressant-like action by modulating the 5-HT, DA and NE levels in the prefrontal cortex.   Key words: Chronic mild stress, mice, antidepressant, neurotransmitter, Bupleurum yinchowense.