Inflammatory cytokines in major depressive disorder: A case–control study

Abstract

Introduction: There is mixed evidence in the literature on the role of inflammation in major depressive disorder. Contradictory findings are attributed to lack of rigorous characterization of study subjects, to the presence of concomitant medical illnesses, to the small sample sizes, and to the limited number of cytokines tested.Methods: Subjects aged 18-70 years, diagnosed with major depressive disorder and presenting with chronic course of illness, as well as matched controls (n = 236), were evaluated by trained raters and provided blood for cytokine measurements. Cytokine levels in EDTA plasma were measured with the MILLIPLEX Multi-Analyte Profiling Human Cytokine/ Chemokine Assay employing Luminex technology. The Wilcoxon rank-sum test was used to compare cytokine levels between major depressive disorder subjects and healthy volunteers, before (interleukin [IL]-1β, IL-6, and tumor necrosis factor-α) and after Bonferroni correction for multiple comparisons (IL-1α, IL-2, IL-3, IL-4, IL-5, IL-7, IL-8, IL-10, IL-12(p40), IL-12(p70), IL-13, IL-15, IFN-γ-inducible protein 10, Eotaxin, interferon-γ, monotype chemoattractant protein-1, macrophage inflammatory protein-1α, granulocyte-macrophage colony-stimulating factor and vascular endothelial growth factor).Results: There were no significant differences in cytokine levels between major depressive disorder subjects and controls, both prior to and after correction for multiple analyses (significance set at p ⩽ 0.05 and p ⩽ 0.002, respectively). Conclusion:Our well-characterized examination of cytokine plasma levels did not support the association of major depressive disorder with systemic inflammation. The heterogeneity of major depressive disorder, as well as a potential sampling bias selecting for non-inflammatory depression, might have determined our findings discordant with the literature.

Aspirin and incident depressive symptoms: A longitudinal cohort study over 8 years

“…In particular, while depressive symptoms correlate with several adverse outcomes, 33 it has been observed that depressive symptoms are also present in the nonclinical general population. 34 Moreover, while in MDD, some studies do not confirm the inflammatory theory of depression, 35 others strongly suggest a subpopulation that could benefit from treatment with antiinflammatory drugs. 36 Hence, our data cannot preclude the possibility that aspirin is beneficial in a subpopulation of individuals with MDD.…”

The Beneficial Effects of Hypiran in Ameliorating Rat Model of Ulcerative Colitis

“…Nevertheless, Hypiran decreased the levels of IL-6 more profoundly than Prednisolone. Interestingly, it is clear that patients with depression disorders show increased levels of proinflammatory cytokines like IL-6 and H. perforatum extract may have beneficial effects in the treatment of depression via decreasing the levels of IL-6 and altering the neuromediators [10,40].…”

Socioeconomic disparities of depressive symptoms and cytokines in hepatocellular carcinoma

“…Therefore, regulatory T cells or myeloid‐derived suppressor cells should be included in future studies to adjust for global elevations in cytokines due to tumor. Lastly, a recent study on cytokine levels of patients with MDD and chronic illness (compared with those of matched controls) found that there is no significant association between measures of systemic inflammation . The authors of the study hypothesized that MDD can be induced by comorbid inflammatory processes mediated by elevated serum cytokines .…”

“…Lastly, a recent study on cytokine levels of patients with MDD and chronic illness (compared with those of matched controls) found that there is no significant association between measures of systemic inflammation. 38 The authors of the study hypothesized that MDD can be induced by comorbid inflammatory processes mediated by elevated serum cytokines. 38 Future studies should recruit otherwise healthy MDD patients as matched controls to study the change of inflammatory cytokines in depressed cancer patients.…”

“…38 The authors of the study hypothesized that MDD can be induced by comorbid inflammatory processes mediated by elevated serum cytokines. 38 Future studies should recruit otherwise healthy MDD patients as matched controls to study the change of inflammatory cytokines in depressed cancer patients.…”