title: Systemic delivery of therapeutics to neuronal tissues: a barrier modulation approach.
abstract: BACKGROUND
  Efficient systemic delivery of low-molecular-mass therapeutics to neuronal tissue remains a central issue not only to drug development but also to the chronic treatment of a range of neurodegenerative disorders.
  
  
  METHODS
  This review discusses the potential of using RNA interference to modulate tight junction proteins at the blood-brain barrier and inner blood-retina barrier. Both systemic delivery of short-interfering RNA and viral-mediated delivery of short hairpin RNA are discussed, highlighting the therapeutic area relevant to each.
  
  
  RESULTS
  Readers will gain an insight into the potential of size-selective and reversible modulation of neuronal barriers and the types of low-molecular-mass molecule that could be used in the treatment of various neurodegenerative or neuromalignant disorders.
  
  
  CONCLUSIONS
  The purpose of this review is to describe a new therapeutic strategy for systemic delivery of low-molecular-mass therapeutics to neuronal tissues.
authors.affiliation: Smurfit Institute of Genetics, Trinity College Dublin, Ocular Genetics Unit, Dublin 2, Ireland. Matthew.Campbell@tcd.ie
authors.forename: Matthew
authors.initials: M
authors.lastname: Campbell
authors.forename: Ema
authors.initials: E
authors.lastname: Ozaki
authors.forename: Peter
authors.initials: P
authors.lastname: Humphries
mesh_terms: D001812:Blood-Brain Barrier; D001813:Blood-Retinal Barrier; D016503:Drug Delivery Systems; D006801:Humans; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D034622:RNA Interference