Positive effects of the traditional Chinese medicine MLC901 in cognitive tasks

MLC901 (NurAiDII) is used as a treatment for stroke patients. It has been shown that MLC901 improves motor and cognitive recovery in ischemic and traumatic brain-injured rodents. The present study seeks to delineate cognitive effects induced by MLC901 in normal, noninjured mice. To this end, the behaviors of vehicle- and MLC901-treated C57BL/6 mice in hippocampus-dependent (passive avoidance, Morris water maze) and hippocampus-independent (novel object recognition) cognitive tasks are compared. The potential influence of the compound on the anxiety level and nycthemeral rhythm of mice is also assessed. In addition, the long-term effects of MLC901 on hippocampal neurogenesis are measured. The results clearly demonstrate that MLC901 promotes extinction in passive avoidance and reversal learning in the Morris water maze and improves the performance of mice in novel object recognition. In parallel, this study shows the long-term proneurogenesis effects of MLC901 that result in the increase in the number of mature neurons in the hippocampus. If these observations can be extended to humans, then MLC901 could represent a promising therapeutic strategy.