Cytokine imbalance in the pathophysiology of major depressive disorder.
OBJECTIVE
A substantial body of evidence indicates that dysregulation of the immune system is associated with Major Depressive Disorder (MDD). Because most cytokines have pleiotropic effects, we measured various subsets of cytokines to examine the association between immune response and MDD.


METHODS
Forty-eight hospitalized MDD patients and 63 normal controls were recruited. We measured in vitro monocytic (IL-6 and tumor necrosis factor (TNF)-alpha), Th1 (interferon (IFN)-gamma and interleukin (IL)-2), Th2 (IL-4), and Treg (transforming growth factor (TGF)-beta1) cytokine production as well as IL-2/IL-4 and IFN-gamma/IL-4 ratios for both groups. Depressive symptoms were assessed by Hamilton Depression Rating Scale. Patients were evaluated before and after 6 weeks of antidepressant treatment.


RESULTS
At admission, IL-6, TNF-alpha, TGF-beta1 production, and IFN-gamma/IL-4 ratio were significantly higher, whereas IFN-gamma, IL-2, and IL-4 were significantly lower in MDD patients. After treatment, IL-6 and TGF-beta1 production were significantly lower than before treatment.


CONCLUSIONS
We suggest that activation of monocytic proinflammatory cytokines, and inhibition of both Th1 and Th2 cytokines may be associated with immunological dysregulation in MDD. TGF-beta1 may be associated with the regulation of monocytic cytokines as well as Th1 and Th2 cytokines in MDD.
Kim
Yong-Ku
YK
Department of Psychiatry, Korea University Ansan Hospital, College of Medicine, South Korea. yongku@korea.ac.kr
Na
Kyeong-Sae
KS
Shin
Kyung-Ho
KH
Jung
Han-Yong
HY
Choi
So-Hyun
SH
Kim
Jung-Bum
JB
D000328:Adult; D000368:Aged; D016207:Cytokines / Q000378:metabolism* / Q000502:physiology*; D003865:Major Depressive Disorder / Q000276:immunology* / Q000378:metabolism* / Q000523:psychology; D004562:Electrocardiography; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D011569:Psychiatric Status Rating Scales; D018417:Th1 Cells / Q000502:physiology; D018418:Th2 Cells / Q000502:physiology; D053773:Transforming Growth Factor beta1 / Q000502:physiology
D016207:Cytokines; D053773:Transforming Growth Factor beta1