Abstract

The effects of chloroform and ethyl acetate extracts of Hedysarum alpinum L. were investigated through a ketamine-induced schizophrenia-like rat model. The quantitation of the total triterpene saponin content of extracts was determined by using oleanolic acid as standard. The ethyl acetate extract had a total triterpene saponin of 10.02 ± 0.02 mg otoacoustic emission (OAE)/g, while the chloroform extract had 8.50 ± 0.05 mg OAE/g, respectively. The neuroprotective effect was evaluated using a schizophrenia-like model induced by ketamine with different behavior tasks, including open-field (for hyperlocomotion evaluation), elevated plus maze (for anxiety examination), and novel object recognition (for memory dysfunction characterization) tests. The rat hippocampus was isolated for biochemical analysis. Ketamine significantly caused hyperlocomotion, anxiety-like behavior, and recognition memory deficit in animals. Oxidative stress induced by ketamine was alleviated by H. alpinum chloroform and ethyl acetate extracts at doses of 40 and 80 mg/kg. The level of malondialdehyde (MDA) and superoxide dismutase (SOD) in rat hippocampus were reduced by pretreatments of both H. alpinum extracts and droperidol. Chloroform and ethyl acetate extracts of HA exhibit antipsychotic and neuroprotective effects through attenuating oxidative stress. The findings suggest that H. alpinum extracts could have the potential to ameliorate schizophrenia-like symptoms.   

Key words: Hedysarum alpinum L., extracts, neuroprotective, antioxidant effects.