title: Acetylcholinesterase-independent protective effects of huperzine A against iron overload-induced oxidative damage and aberrant iron metabolism signaling in rat cortical neurons.
abstract: OBJECTIVE
  Iron dyshomeostasis is one of the primary causes of neuronal death in Alzheimer's disease (AD). Huperzine A (HupA), a natural inhibitor of acetylcholinesterase (AChE), is a licensed anti-AD drug in China and a nutraceutical in the United Sates. Here, we investigated the protective effects of HupA against iron overload-induced injury in neurons.
  
  
  METHODS
  Rat cortical neurons were treated with ferric ammonium citrate (FAC), and cell viability was assessed with MTT assays. Reactive oxygen species (ROS) assays and adenosine triphosphate (ATP) assays were performed to assess mitochondrial function. The labile iron pool (LIP) level, cytosolic-aconitase (c-aconitase) activity and iron uptake protein expression were measured to determine iron metabolism changes. The modified Ellman's method was used to evaluate AChE activity.
  
  
  RESULTS
  HupA significantly attenuated the iron overload-induced decrease in neuronal cell viability. This neuroprotective effect of HupA occurred concurrently with a decrease in ROS and an increase in ATP. Moreover, HupA treatment significantly blocked the upregulation of the LIP level and other aberrant iron metabolism changes induced by iron overload. Additionally, another specific AChE inhibitor, donepezil (Don), at a concentration that caused AChE inhibition equivalent to that of HupA negatively, influenced the aberrant changes in ROS, ATP or LIP that were induced by excessive iron.
  
  
  CONCLUSIONS
  We provide the first demonstration of the protective effects of HupA against iron overload-induced neuronal damage. This beneficial role of HupA may be attributed to its attenuation of oxidative stress and mitochondrial dysfunction and elevation of LIP, and these effects are not associated with its AChE-inhibiting effect.
authors: CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Ling-Xue
authors: LX
authors: Tao
authors: CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Xiao-Tian
authors: XT
authors: Huang
authors: CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Yu-Ting
authors: YT
authors: Chen
authors: CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Xi-Can
authors: XC
authors: Tang
authors: CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Hai-Yan
authors: HY
authors: Zhang
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism*; D005290:Ferric Compounds / Q000494:pharmacology; D007501:Iron / Q000378:metabolism*; D019190:Iron Overload / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018384:Oxidative Stress; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D012717:Sesquiterpenes / Q000494:pharmacology*; D015398:Signal Transduction
chemical_list: D000470:Alkaloids; D000975:Antioxidants; D005290:Ferric Compounds; D000644:Quaternary Ammonium Compounds; D017382:Reactive Oxygen Species; D012717:Sesquiterpenes; C050426:huperzine A; D000255:Adenosine Triphosphate; D007501:Iron; D000110:Acetylcholinesterase; C013531:ferric ammonium citrate