title: The role of epigenetics in cognitive ageing.
abstract: OBJECTIVE
  As the population is ageing, a better understanding of the underlying causes of age-related cognitive decline (cognitive ageing) is required. Epigenetic dysregulation is proposed as one of the underlying mechanisms for cognitive ageing. We review the current knowledge on epigenetics and cognitive ageing and appraise the potential of epigenetic preventative and therapeutic interventions.
  
  
  METHODS
  Articles on cognitive ageing and epigenetics in English were identified.
  
  
  RESULTS
  Epigenetic dysregulation occurs with cognitive ageing, with changes in histone post-translational modifications, DNA methylation and non-coding RNA reported. However, human studies are lacking, with most being cross-sectional using peripheral blood samples. Pharmacological and lifestyle factors have the potential to change aberrant epigenetic profiles; but few studies have examined this in relation to cognitive ageing.
  
  
  CONCLUSIONS
  The relationship between epigenetic modifications and cognitive ageing is only beginning to be investigated. Epigenetic dysregulation appears to be an important feature in cognitive ageing, but whether it is an epiphenomenon or a causal factor remains to be elucidated. Clarification of the relationship between epigenetic profiles of different cell types is essential and would determine whether epigenetic marks of peripheral tissues can be used as a proxy for changes occurring in the brain. The use of lifestyle and pharmacological interventions to improve cognitive performance and quality of life of older adults needs more investigation.
authors.affiliation: Centre for Healthy Brain Ageing, Psychiatry, University of New South Wales, Sydney, Australia.
authors.forename: Karen A
authors.initials: KA
authors.lastname: Mather
authors.forename: John B
authors.initials: JB
authors.lastname: Kwok
authors.forename: Nicola
authors.initials: N
authors.lastname: Armstrong
authors.forename: Perminder S
authors.initials: PS
authors.lastname: Sachdev
mesh_terms: D000375:Aging / Q000235:genetics*; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000235:genetics* / Q000628:therapy; D019175:DNA Methylation; D057890:Epigenomics; D059647:Gene-Environment Interaction; D056572:Histone Deacetylase Inhibitors / Q000627:therapeutic use; D006657:Histones / Q000378:metabolism; D006801:Humans; D008019:Life Style
chemical_list: D056572:Histone Deacetylase Inhibitors; D006657:Histones
keywords: DNA methylation; RNA; ageing; cognitive ageing; epigenetics; gene expression; histones