Neuroprotective effects of Dioscorea opposita on scopolamine-induced memory impairment in in vivo behavioral tests and in vitro assays.

ETHNOPHARMACOLOGICAL RELEVANCE

Plants belong to the genus Dioscorea have long been used as edible tuber crops in many tropical and subtropical areas and as a traditional herbal medicine in oriental countries including China, Japan and Korea.

AIM OF THE STUDY

In this study, in vivo and in vitro tests were carried out to evaluate the cognitive enhancing effects of CHCl(3)-soluble extract from Dioscorea opposita against scopolamine-induced amnesic mice and glutamate- and H(2)O(2)-treated cortical neurons of rats.

MATERIALS, METHODS AND RESULTS: Acute treatment (200 mg/kg body weight, p.o.) and 10 days' daily administration (50 mg/kg body weight, p.o.) of CHCl(3)-soluble extract showed significant spatial learning and memory improvement on mice. Furthermore, the neuroprotective effects on glutamate- and H(2)O(2)-induced neurotoxicity in primary cultured cortical neurons of rats were assessed. Pretreatment with the extract was found to impart significant protection against neurotoxicity.

CONCLUSIONS

These in vivo and in vitro results suggest that the Dioscorea opposita has neuroprotective effects on memory impairment related neurodegenerative diseases.