Joshua Hyong-Jin Cho, Sara M Shu, Ariya Mahbod, Michael R Irwin
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引用次数: 0
Abstract
Background: Inflammation is involved in the pathophysiology of depression, and circulating inflammatory cytokines have been associated with depressive symptoms. However, measuring circulating cytokines have inherent methodological limitations. In vitro lipopolysaccharide (LPS)-stimulated intracellular cytokines (ICCs) overcome these limitations. Furthermore, because psychosocial and physiological stressors activate inflammatory responses and LPS-stimulated ICCs reflect the inflammatory responsivity of monocytes to such stressors, ICCs may reflect individual stress responsivity.
Methods: This cross-sectional study examined whether LPS-stimulated expression of ICCs in peripheral blood mononuclear cells (PBMCs) is a sensitive inflammation measure correlated with depressive symptoms in 180 community-dwelling older adults. We tested correlations of not only intracellular but also circulating inflammatory markers with depressive symptoms assessed using the 10-item Center for Epidemiological Studies Depression Scale (CES-D). Intracellular markers included expression of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and both in PBMCs. Circulating markers included IL-6, TNF-α, and C-reactive protein (CRP) in plasma.
Results: None of the correlations were statistically significant. However, in contrast to circulating markers, the correlations of ICCs were consistently in the expected direction, i.e., higher ICC expression correlating with higher depression severity.
Discussion: Despite the non-significant findings, further research is required for the evaluation of LPS-stimulated ICC expression as biomarkers of depressive symptoms.
期刊介绍:
The mission of the Archives of Clinical Psychiatry is to provide relevant clinical information and clinically oriented research, including also basic research, whose results have potential implications for clinical practice. The scope of the journal encompasses: Human Sciences, Basic and Clinical Neuroscience, and Clinical Psychiatry. The Archives of Clinical Psychiatry strives to inform and to educate mental health care professionals and to stimulate debates and further exploration into the nature, causes, treatment, and public health importance of mental health issues.