title: Neuroprotective effects of Tongmai Yizhi Decoction () against Alzheimer's disease through attenuating cyclin-dependent kinase-5 expression.
abstract: OBJECTIVE
  To explore the protective effects of Tongmai Yizhi Decoction (, TYD), a Chinese herb complex prescription against the impairment of cognitive functions and memory loss in amyloid beta 1-40 (Aβ1-40) peptide and ibotenic (IBO)-induced Alzheimer's disease (AD) model rats.
  
  
  METHODS
  The in vivo model was established by injecting Aβ1-40and IBO into left hippocampal CA1 area of Sprague-Dawley (SD) rat to mimic AD. Totally 32 SD rats were divided into 4 groups, including sham operation group, AD model group, TYD group [AD rats treated with TYD at the dosage of 19.44 g/(kg•d) for 4 weeks] and huperzine A group [AD rats treated with huperzine A at the dosage of 40.5 μg/(kg•d) for 4 weeks]. Spatial learning and memory level was detected by Morris Water Maze test. Histological morphology in the hippocampus was tested by hematoxylin-eosin (HE) staining. Cyclin-dependent kinase-5 (Cdk5) protein and gene expression level were investigated by Western blot analysis and real-time quantitative polymerase chain reaction (RT-qPCR), respectively.
  
  
  RESULTS
  Aβ1-40 and IBO treatment induced longer escape latency of rats, compared with sham operation group from day 25 (P<0.01). However, TYD and huperzine A obviously shortened the escape latency from day 26 (P<0.01). Moreover, the effect of TYD was similar to huperzine A (P>0.05). Furthermore, HE staining also showed that TYD and huperzine A reversed the neuropathological changes in the hippocampus triggered by Aβ1-40 and IBO. TYD and huperzine A effectively reduced the expression levels of Cdk5 protein and gene located in rat hippocampus, compared with the AD model group (P<0.01).
  
  
  CONCLUSIONS
  TYD could be a promising neuroprotective agent for protecting neuron from AD injury through inhibiting Cdk5 expression.
authors.affiliation: The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
authors.forename: Jing-Han
authors.initials: JH
authors.lastname: Feng
authors.affiliation: Pharmacy College, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
authors.forename: Bao-Chang
authors.initials: BC
authors.lastname: Cai
authors.affiliation: The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China. gwfwfg2003@sina.com.
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Guo
authors.affiliation: Basic Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
authors.forename: Ming-Yan
authors.initials: MY
authors.lastname: Wang
authors.affiliation: The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ma
authors.affiliation: The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
authors.forename: Qiao-Xi
authors.initials: QX
authors.lastname: Lu
mesh_terms: D032429:Alpinia; D000544:Alzheimer Disease / Q000188:drug therapy* / Q000473:pathology; D000818:Animals; D003071:Cognition / Q000187:drug effects; D051360:Cyclin-Dependent Kinase 5 / Q000378:metabolism; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000627:therapeutic use*; D005260:Female; D006624:Hippocampus / Q000187:drug effects; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008568:Memory / Q000187:drug effects; D018696:Neuroprotective Agents / Q000627:therapeutic use*; D010936:Plant Extracts; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: C442779:Alpinia oxyphylla fruit extract; D004365:Drugs, Chinese Herbal; D018696:Neuroprotective Agents; D010936:Plant Extracts; C000617194:tongmai yizhi; D051360:Cyclin-Dependent Kinase 5
keywords: Alzheimer's disease; Chinese medicine; Tongmai Yizhi Decoction; cyclin-dependent kinase-5