Ginsenoside Rh2 Improves Learning and Memory in Mice

A wide range of plant foods and dietary supplements are able to modify the functioning of the central nervous system. In the present study, we observed that oral administration of ginsenoside Rh₂ (10 mg/mL) for 3 weeks significantly improved spatial learning and memory. Spatial memory and learning was evaluated in mice by hippocampus-dependent tasks (Morris water maze test) and immunohistochemical marker of cell genesis bromodeoxyuridine. Ginsenoside Rh₂ treatment (30 days) promoted cell survival and genesis. Further, ginsenoside Rh₂ treatment in enriched condition had no significant effects on cell survival compared with standard condition exposure. These results revealed that ginsenoside Rh₂-mediated spatial learning and memory improvement was associated with cell genesis and survival and may be parallel to the mechanism of environmental enrichment. Therefore, ginsenoside Rh₂ may have efficacy as a dietary supplement for spatial learning and memory improvement.