title: Schizandrin ameliorates ovariectomy-induced memory impairment, potentiates neurotransmission and exhibits antioxidant properties.
abstract: OBJECTIVE
  Schizandrin (SCH) has been reported to prevent or reduce learning and memory defects. However, it is not known whether SCH ameliorates cognitive impairments induced by oestrogen deficiency. In the present study, we investigated the effect of SCH on memory in ovariectomized (OVX) and non-OVX rats.
  
  
  METHODS
  A passive avoidance test was used to evaluate the effect of SCH on memory. Field EPSPs were recorded in hippocampal slices using an electrophysiological method. In OVX rats, biochemical parameters in the bilateral hippocampus were measured; these included superoxide dismutase (SOD), malondialdehyde (MDA) and AChE. Also, the number of NADPH-diaphorase (NADPH-d) positive neurons was counted by NADPH-d histochemistry staining technique.
  
  
  RESULTS
  Oral SCH improved the memory and facilitated the induction of long-term potentiation in non-OVX and OVX rats; this effect was more obvious in OVX rats. Similarly, SCH perfusion enhanced synaptic transmission in hippocampal slices from both non-OVX and OVX rats. However, SCH perfusion reduced the ratio of paired-pulse facilitation only in OVX but not in non-OVX rats. In addition, SCH decreased AChE activity and MDA level and increased SOD activity and the number of NADPH-d-positive neurons in OVX rats.
  
  
  CONCLUSIONS
  SCH improves memory in OVX rats and its potential mechanisms may include a reduction in the loss of hippocampal NADPH-d positive neurons, an increase of antioxidant properties and a potentiation of synaptic transmission that possibly involves to enhance cholinergic function. Overall, our findings indicate that SCH has potential as a therapeutic strategy for the cognitive dysfunctions associated with the menopause.
authors.affiliation: School of Life Science, South China Normal University, Guangzhou, China.
authors.forename: Zhong-Jiao
authors.initials: ZJ
authors.lastname: Jiang
authors.forename: Chun-Yang
authors.initials: CY
authors.lastname: Wang
authors.forename: Xun
authors.initials: X
authors.lastname: Xie
authors.forename: Jing-Fang
authors.initials: JF
authors.lastname: Yang
authors.forename: Jun-Ni
authors.initials: JN
authors.lastname: Huang
authors.forename: Zhi-Ping
authors.initials: ZP
authors.lastname: Cao
authors.forename: Peng
authors.initials: P
authors.lastname: Xiao
authors.forename: Chu-Hua
authors.initials: CH
authors.lastname: Li
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use; D001362:Avoidance Learning / Q000187:drug effects; D002452:Cell Count; D034242:Cyclooctanes / Q000494:pharmacology* / Q000627:therapeutic use*; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D005260:Female; D058851:GPI-Linked Proteins / Q000378:metabolism; D006624:Hippocampus / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D017705:Lignans / Q000494:pharmacology* / Q000627:therapeutic use*; D017774:Long-Term Potentiation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D008569:Memory Disorders / Q000139:chemically induced / Q000188:drug therapy*; D010052:Ovariectomy / Q000009:adverse effects*; D011083:Polycyclic Compounds / Q000494:pharmacology* / Q000627:therapeutic use*; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects*
chemical_list: D000975:Antioxidants; D034242:Cyclooctanes; D058851:GPI-Linked Proteins; D017705:Lignans; D011083:Polycyclic Compounds; D008315:Malondialdehyde; D013482:Superoxide Dismutase; D000110:Acetylcholinesterase; C548246:Ache protein, rat; C011105:schizandrin