title: [Clinical Applications of Peripheral Markers of Response in Antidepressant Treatment: Neurotrophins and Cytokines].
abstract: BACKGROUND
  Explanatory theories of depression have advanced in recent decades from the monoaminergic hypothesis to neurogenesis alterations to the neurohormonal hypothesis that includes the dysfunction of the inflammatory response. Currently there is a growing interest in the development of biomarkers that can contribute to diagnosis and proper treatment.
  
  
  OBJECTIVE
  To describe the role of neurotrophins such as brain-derived neurotrophic factor (BDNF) and cytokines in the pathophysiology of depressive disorder in addition to reviewing and analyzing evidence about their clinical application as biomarkers of antidepressant therapy.
  
  
  METHODS
  Relevant data research in several databases.
  
  
  CONCLUSIONS
  In recent years evidence of alterations in neurogenesis mediated by the expression of BDNF in the hippocampus in the pathophysiology of depression has increased and there is ample evidence that BDNF is a marker of the diagnosis of depressive disorder and also of treatment effectiveness. There is little information about other neurotrophins. There has also been increased interest in relation to depression as an "inflammatory disease" and the link with cytokines in its pathogenesis. Evidence has been found for the usefulness of some cytokines especially IL-1 (interleukin 1), IL-6 (interleukin 6), and TNF (tumor necrosis factor) as biomarkers of antidepressant drug response in humans.
authors.affiliation: Médica psiquiatra, estudiante del Doctorado en Salud Mental, Universidad de Concepción, Concepción, Chile. Electronic address: constanzamendozab@gmail.com.
authors.forename: Constanza Mendoza
authors.initials: CM
authors.lastname: Bermúdez
keywords: Brain-derived neurotrophic factor; Factor neurotrófico derivado del cerebro; biomarcadores; biomarkers; citocinas; cytokines; depresión; depression; neurotrofinas; neurotrophins