title: [An in vitro study on the pharmacological ascorbate treatment of influenza virus].
abstract: OBJECTIVE
  To investigate the effects and mechanism of pharmacological ascorbate against Influenza A/CA/7/09 (H1N12009).
  
  
  METHODS
  NHBE cells (≈ 95% confluent monolayer) in 12-well plates (Corning) were kept at 37°C at all times. NHBE cells were exposed to A/CA/7/09 (H1N12009) influenza virus at MOI of 0.01 for 1 h, rinsed with NHBE medium, and incubated with NHBE medium containing 20 mmol/L ascorbate or 20 mmol/L ascorbate +600 IU/ml Catalase. The cells were then incubated for an additional 4 - 12 h and the culture medium was harvested for titration. Viral titers were determined as log(10) 50% tissue culture infective doses (TCID₅₀) assay in MDCK cells. Ascorbate in NHBE medium was determined using HPLC separation coupled with coulometric electrochemical detection. Hydrogen peroxide was detected indirectly by Clark-type oxygen electrode.
  
  
  RESULTS
  In vitro experiments showed that pharmacological ascorbate killed not only isolated viruses, but also viruses from normal human bronchial epithelial cells. The antiviral effect of ascorbic acid appeared to be dose-dependent. 2.5 mmol/L ascorbic acid was able to eliminate 90% of the viruses and 20 mmol/L ascorbic acid totally blocked viral replication in vitro. The antiviral effect of pharmacological ascorbate varied at different phases of infection. Pharmacological ascorbate eliminated viral infectivity with treatment times as short as 4 hours at early stage of infection. But the effect was reversed by catalase.
  
  
  CONCLUSIONS
  Pharmacological ascorbate (vitamin C) as a pro-drug eliminates or kills influenza virus, probable by producing steady-state concentrations of hydrogen peroxide (H₂O₂) in extracellular fluid.
authors.affiliation: The State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Diseases, the First Affiliated Hospital, Guangzhou Medical University, China. chenglinling@gmail.com
authors.forename: Lin-ling
authors.initials: LL
authors.lastname: Cheng
authors.forename: Ya-ya
authors.initials: YY
authors.lastname: Liu
authors.forename: Bing
authors.initials: B
authors.lastname: Li
authors.forename: Shi-yue
authors.initials: SY
authors.lastname: Li
authors.forename: Pi-xin
authors.initials: PX
authors.lastname: Ran
mesh_terms: D000998:Antiviral Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D002478:Cells, Cultured; D003470:Culture Media; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000821:virology; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D009975:Orthomyxoviridae / Q000187:drug effects*; D012137:Respiratory System / Q000166:cytology
chemical_list: D000998:Antiviral Agents; D003470:Culture Media; D006861:Hydrogen Peroxide; D001205:Ascorbic Acid