title: Neuroinflammation as a possible link between cannabinoids and addiction.
abstract: OBJECTIVE
  Substance dependence disorder is a chronically relapsing condition characterised by neurobiological changes leading to loss of control in restricting a substance intake, compulsion and withdrawal syndrome. In the past few years, (endo)cannabinoids have been raised as a possible target in the aetiology of drug addiction. On the other hand, although the exact mechanisms of the genesis of addiction remain poorly understood, it is possible that neuroinflammation might also play a role in the pathophysiology of this condition. Studies demonstrated that (endo)cannabinoids act as immunomodulators by inhibiting cytokines production and microglial cell activation. Thus, in the present review, we explore the possible role of neuroinflammation on the therapeutic effects of cannabinoids on drug addiction.
  
  
  METHODS
  We conducted an evidence-based review of the literature in order to assess the role of cannabinoids on the neuroinflammatory hypothesis of addiction (terms: addiction, cannabinoids and inflammation). We searched PubMed and BioMedCentral databases up to April 2014 with no date restrictions.
  
  
  RESULTS
  In all, 165 eligible articles were included in the present review. Existing evidence suggests that disruption in cannabinoid signalling during the drug addiction process leads to microglial activation and neuroinflammation.
  
  
  CONCLUSIONS
  The literature showed that inflammation and changes in endocannabinod signalling occur in drug abuse; however, it remains uncertain whether these changes are causally or coincidentally associated with addiction. Additional studies, therefore, are needed to elucidate the contribution of neuroinflammation on the behavioural and neuroprotective effects of cannabinoids on drug addiction.
authors.affiliation: 1Department of Physiological Sciences,Health Science Center,Universidade Federal do Espírito Santo,Vitoria,Brazil.
authors.forename: Livia C M
authors.initials: LC
authors.lastname: Rodrigues
authors.affiliation: 2Department of Pharmacology,Institute of Biological Sciences,Universidade Federal de Minas Gerais,Belo Horizonte,Brazil.
authors.forename: Pedro H
authors.initials: PH
authors.lastname: Gobira
authors.affiliation: 2Department of Pharmacology,Institute of Biological Sciences,Universidade Federal de Minas Gerais,Belo Horizonte,Brazil.
authors.forename: Antonio Carlos
authors.initials: AC
authors.lastname: de Oliveira
authors.affiliation: 1Department of Physiological Sciences,Health Science Center,Universidade Federal do Espírito Santo,Vitoria,Brazil.
authors.forename: Renan
authors.initials: R
authors.lastname: Pelição
authors.affiliation: 3Group of Neuroimmunology,Laboratory of Immunopharmacology,Institute of Biological Sciences,Universidade Federal de Minas Gerais,Belo Horizonte,Brazil.
authors.forename: Antonio Lucio
authors.initials: AL
authors.lastname: Teixeira
authors.affiliation: 2Department of Pharmacology,Institute of Biological Sciences,Universidade Federal de Minas Gerais,Belo Horizonte,Brazil.
authors.forename: Fabricio A
authors.initials: FA
authors.lastname: Moreira
authors.affiliation: 3Group of Neuroimmunology,Laboratory of Immunopharmacology,Institute of Biological Sciences,Universidade Federal de Minas Gerais,Belo Horizonte,Brazil.
authors.forename: Alline Cristina
authors.initials: AC
authors.lastname: Campos
mesh_terms: D016739:Behavior, Addictive / Q000209:etiology* / Q000276:immunology / Q000378:metabolism; D002186:Cannabinoids / Q000378:metabolism*; D006801:Humans; D017628:Microglia / Q000378:metabolism / Q000473:pathology; D043884:Receptor, Cannabinoid, CB1 / Q000378:metabolism; D015398:Signal Transduction; D019966:Substance-Related Disorders / Q000209:etiology* / Q000276:immunology / Q000378:metabolism
chemical_list: D002186:Cannabinoids; D043884:Receptor, Cannabinoid, CB1