ABSTRACT
Objective: To study the effect and action mechanism of Liuwei Dihuang(LW)active fraction combi- nation(LW-AFC)on learning and memory impairment of neuroinflammatory model induced by lipopolysaccharide(LPS). Methods: The C57 mice were randomly divided into control group, model group, positive drug group and test groups ac- cording to their autonomic activity and body mass. The mice in the test groups were orally given LW[1.17 g/(kg•d)]and LW-AFC[1.6 g/(kg•d)]for two weeks in advance. The spatial learning and memory ability of the mice in each group were evaluated by Morris water maze test;immunofluorescence was used to observe the activation of microglia in the brain;Luminex 200 was used to detect the level of inflammatory cytokines in peripheral blood and hippocampus. Results: LW-AFC could improve the spatial learning and memory impairment induced by a single intraperitoneal injection (ip)of LPS(P<0.05); the activation of glial cells in the brain was inhibited(P<0.01);the levels of IL-6 and MCP-1 in the hippocampus were reduced(P<0.05). Conclusion: LW-AFC could reduce the neuroinflammation caused by the activation of microglia in brain, but could not effectively ameliorate the spatial learning and memory impairment caused by the activation of microglia in hippocampus.