Objective To explore the effects of Humanin(HN)on the spatial memory and its mechanism in rats with Aβ_(1-42)-induced Alzheimer's disease.Methods Thirty-six Wistar rats were randomly divided into 3 groups:saline group,AD model group and HN-treatment group.The AD models were established by injection of Aβ_(1-42) into the hippocampus.HN-treatment group was given 2 μL HN at the same site after the success of model making.The spatial memory ability of the rats was tested with Morris water maze.Immunohistochemistry was used to detect the expression of microtubule associated protein 2(MAP2).The protein level of synapsin 1 was detected by Western blotting.Results AD model group showed significantly longer latency and decreased expression of MAP2 than that of the saline group(P<0.05);however,no significant differences of the latency and expression of MAP2 were found between the AD model group and the HN-treatment group(P>0.05).The expression of synapsin 1 in the HN-treatment group was significantly higher than that in the saline and the AD model groups(P<0.05);while no significant differences between the saline and AD model groups were found(P>0.05).Conclusion HN can improve the spatial memory of rats with Aβ_(1-42)-induced AD through iucreasing the expression of MAP2 and sympsin 1.

It was estimated that about 428 species of genus Corydalis are distributed all worldwide, with about 298, especially 10 groups and 219 species being uniquely spread in China. The genus Corydalis have been widely employed as folk medicines in China, especially as traditional Tibetan medicines, for treatment of fever, hepatitis, edema, gastritis, cholecystitis, hypertension and other diseases. The phytochemical studies revealed that isoquinoline alkaloids are its major bioactive ingredients. The extensive biological researches suggested its pharmacological activities and clinic applications against cardiovascular diseases and central nervous system, antibacterial activities, analgesic effects, anti-inflammatory, anti-oxidation and anti-injury for hepatocyte, and so on. As an effort in promoting the research of pharmacodynamic ingredients, this article presents an overview focusing on the distribution, phytochemical and pharmacological results of Corydalis species that have been applied in traditional Tibetan medicinal, hopefully to provide a reference for the new Tibetan medicine development from Corydalis plant resource.
Alkaloids ; chemistry ; pharmacology ; Animals ; Anti-Infective Agents ; chemistry ; pharmacology ; Corydalis ; chemistry ; classification ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Humans ; Mice ; Molecular Structure ; Phytotherapy