title: Ethanol reduces amyloid aggregation in vitro and prevents toxicity in cell lines.
abstract: BACKGROUND
  Alzheimer's disease (AD) alters cognitive functions. A mixture of soluble β-amyloid aggregates (Aβ) are known to act as toxic agents. It has been suggested that moderate alcohol intake reduces the development of neurodegenerative diseases, but the molecular mechanisms leading to this type of prevention have been elusive. We show the ethanol effect in the generation of complex Aβ in vitro and the impact on the viability of two cell lines.
  
  
  METHODS
  The effect of ethanol on the kinetics of β-amyloid aggregation in vitro was assessed by turbimetry. Soluble- and ethanol-treated β-amyloid were added to the cell lines HEK and PC-12 to compare their effects on metabolic activity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. In addition, we used molecular modeling to assess the impact of exposure to ethanol on the structure of β-amyloid.
  
  
  RESULTS
  Exposure to soluble β-amyloid was toxic to both cell lines; however, exposing the cells to β-amyloid aggregated in 10 mmol ethanol prevented the effect. In silico modeling suggested that ethanol alters the dynamics for assembling Aβ by disrupting a critical salt bridge between residues Asp 23 and Lys 28, required for amyloid dimerization. Thus, ethanol prevented the formation of complex short (∼100 nm) Aβ, which are related to higher cell toxicity.
  
  
  CONCLUSIONS
  Ethanol prevents the formation of stable Aβ dimers in vitro, thus protecting the cells maintained in culture. Accordingly, in silico modelling predicts that soluble β-amyloid molecules do not form stable multimers when exposed to ethanol.
authors.affiliation: Laboratorio de Fisiología de la Reproducción, Núcleo de Investigación en Producción Alimentaria, Facultad de Recursos Naturales, Escuela de Medicina Veterinaria, Universidad Católica de Temuco, Chile.
authors.forename: David
authors.initials: D
authors.lastname: Ormeño
authors.forename: Fernando
authors.initials: F
authors.lastname: Romero
authors.forename: Julio
authors.initials: J
authors.lastname: López-Fenner
authors.forename: Andres
authors.initials: A
authors.lastname: Avila
authors.forename: Ataulfo
authors.initials: A
authors.lastname: Martínez-Torres
authors.forename: Jorge
authors.initials: J
authors.lastname: Parodi
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D000682:Amyloid / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000633:toxicity*; D016229:Amyloid beta-Peptides / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity*; D000818:Animals; D000431:Ethanol / Q000494:pharmacology*; D057809:HEK293 Cells; D006801:Humans; D056004:Molecular Dynamics Simulation; D009391:Nephelometry and Turbidimetry; D016716:PC12 Cells; D051381:Rats
chemical_list: D000682:Amyloid; D016229:Amyloid beta-Peptides; D000431:Ethanol