title: Neuroprotective effects of ginsenoside Rg1 against oxygen-glucose deprivation in cultured hippocampal neurons.
abstract: BACKGROUND
  Ginsenoside Rg1 (Rg1) is believed to be one of the main active principles in ginseng, a traditional Chinese medicine extensively used to enhance stamina and deal with fatigue as well as physical stress. It has been reported that Rg1 performs multiple biological activities, including neuroprotective activity. In this study, we investigated the efficacy of ginsenoside Rg1 on ischemia-reperfusion injury in cultured hippocampal cells and also probed its possible mechanisms.
  
  
  METHODS
  To establish a model of oxygen-glucose deprivation (OGD) and reperfusion, cultured hippocampal neurons were exposed to OGD for 2.5 hours, followed by a 24-hour reoxygenation. Cultured hippocampal neurons were randomly divided into control group, model group (vehicle), and ginsenoside Rg1 treatment groups (5μM, 20μM, 60μM). At 24 hours post-OGD, the intracellular free calcium concentration was detected using Furo-3/AM-loaded hippocampal neurons deprived of oxygen and glucose. Neuronal nitric oxide synthase (nNOS) activity was measured by chemical colorimetry. Cell apoptosis was evaluated by Hoechst staining, and the neuron viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.
  
  
  RESULTS
  Excitotoxic neuronal injury of OGD was demonstrated by the increase of intracellular free calcium concentrations and elevated nNOS activity in the model group compared with the control group. The intracellular free calcium concentrations and the nNOS activity in the groups receiving intermediate and high dose of ginsenoside Rg1 were significantly lower than those of the control group (p < 0.05). In addition, intermediate and high dose of ginsenoside Rg1 administration could also attenuate the cell viability loss (p < 0.05) and cell apoptosis induced by OGD.
  
  
  CONCLUSIONS
  Ginsenoside Rg1 has neuroprotective effect on ischemia-reperfusion injury in cultured hippocampal cells mediated by blocking calcium over-influx into neuronal cells and decreasing the nNOS activity after OGD exposure. We infer that ginsenoside Rg1 may serve as a potential therapeutic agent for cerebral ischemia injury.
authors.affiliation: Department of Neurology, The First Hospital of Xuzhou, Xuzhou, Jiangsu, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: He
authors.affiliation: Department of Neurology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Sun
authors.affiliation: Department of Neurology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Neurology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Emergency Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China. Electronic address: hbhbwywy34@sina.com.
authors.forename: Bin
authors.initials: B
authors.lastname: He
mesh_terms: D000818:Animals; D002118:Calcium / Q000633:toxicity; D002478:Cells, Cultured; D002491:Central Nervous System Agents / Q000494:pharmacology*; D036145:Ginsenosides / Q000494:pharmacology*; D005947:Glucose / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects*; D010100:Oxygen / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000503:physiopathology*
chemical_list: D002491:Central Nervous System Agents; D036145:Ginsenosides; D005947:Glucose; C035054:ginsenoside Rg1; D010100:Oxygen; D002118:Calcium
keywords: calcium overload; cerebral ischemia; ginsenoside Rg1; hippocampal neurons; nitric oxide synthase