[Brain-immune interactions and implications in psychiatric disorders].
OBJECTIVE
This review will focus on the role of cytokines in the central nervous system and its implications to depressive disorder. We will then discuss the main findings of cytokine measurements in patients with major depressive disorder.


METHODS
We searched Pubmed for studies published from 1999-2007, using the keywords depression and cytokine; and depressive disorder and cytokine. We have focused on pro-inflammatory cytokine measurements in patients with depression syndrome using DSM-criteria.


RESULTS
Several lines of evidence suggest that cytokines have effects on depression, such as the induction of sickness behavior; clinical conditions related to cytokines that also overlap depressive symptoms; and immunotherapy that can lead to depressive symptoms attenuated by antidepressant treatment. Finally, patients with depression exhibit increased levels of pro-inflammatory cytokines, although conflicting results have been described.


CONCLUSIONS
Cytokines may play a role in the pathophysiology of some cases of depression, although a causal link has not been established yet. Further longitudinal studies are needed to determine patterns of cytokine in patients with major depressive disorder, taking into account confounding factors closely associated with the activation of pro-inflammatory cytokines. In addition, simultaneous measurements of multiple biomarkers could provide critical insights into mechanisms underlying major depressive disorder and a variety of common cytokine-related diseases.
Marques
Andrea H
AH
Section on Neuroendocrine Immunology, National Institute of Mental Health, Integrative Neural Immune Program, Bethesda-Rockville, Maryland 20852, USA. marquesa@mail.nih.gov
Cizza
Giovanni
G
Sternberg
Esther
E
D000928:Antidepressive Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism / Q000502:physiology*; D003863:Depression / Q000276:immunology / Q000503:physiopathology*; D003866:Depressive Disorder / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology*; D003865:Major Depressive Disorder / Q000503:physiopathology; D006801:Humans; D007107:Immune System / Q000276:immunology / Q000503:physiopathology; D015213:Neuroimmunomodulation / Q000502:physiology*; D013315:Stress, Psychological / Q000503:physiopathology
D000928:Antidepressive Agents; D015415:Biomarkers; D016207:Cytokines