TitleDistinct inflammatory response patterns are evident among men and women with higher depressive symptoms.
Publication TypeJournal Article
Year of Publication2018
AuthorsMajd, M, Graham-Engeland, JE, Smyth, JM, Sliwinski, MJ, Lipton, RB, Katz, MJ, Engeland, CG
JournalPhysiol Behav
Date Published2018 Feb 01
KeywordsAdult, Blood Cells, Cytokines, Depressive Disorder, Female, Humans, Lipopolysaccharides, Male, Middle Aged, Psychiatric Status Rating Scales, Regression Analysis, Sex Characteristics

<p>Extensive research links depression and inflammation, with emerging evidence suggesting some differences between males and females in these associations. However, relatively few studies have examined stimulated inflammatory responses (ex vivo) in depression. The present research investigated the associations between depressive symptoms, basal inflammation, and LPS-stimulated production of pro- (IL-1β, IL-6, IL-8, TNF-α) and an anti-inflammatory cytokine (IL-10), with a focus on the extent to which gender moderates these relationships. As part of a larger study, 162 socio-economically and racially diverse subjects (ages 25-65, 67% women) completed extensive self-report measures, including depressive symptoms. Whole blood was quantified for basal inflammation, or incubated with 1μg/mL lipopolysaccharide (LPS) for 2h (at 37°C, 5% CO) to quantify inflammatory responses to bacterial challenge. We examined the associations between depression and inflammatory markers in regression analyses, controlling for age, BMI, race/ethnicity, income, education, and use of medications. No main effects were observed between depressive symptoms and basal or stimulated levels of inflammation. Moderation analyses revealed a significant interaction between depressive symptoms and gender for stimulated TNF-α, stimulated IL-6 (p<0.05), and a marginally significant interaction for stimulated IL-10 (p=0.07). For men, higher depressive symptoms were associated with significantly higher production of TNF-α (p<0.05) and marginally higher IL-6 (p=0.07), but not with the anti-inflammatory cytokine IL-10. For women, higher depressive symptoms were associated with significantly lower production of TNF-α and IL-10 (ps<0.05), and marginally lower IL-6 (p=0.06). These findings provide evidence for gender differences in the association of depressive symptoms with inflammatory response patterns, and highlight the utility of assessing ex vivo immune responses in blood. Implications for health are discussed.</p>

Alternate JournalPhysiol Behav
PubMed ID29133231
PubMed Central IDPMC5841550
Grant List1UL1TR001073 / NH / NIH HHS / United States
R01 AG039409 / AG / NIA NIH HHS / United States
R01 AG039409 / NH / NIH HHS / United States
R01 AG042595 / NH / NIH HHS / United States
R01 AG042595 / AG / NIA NIH HHS / United States
UL1 TR001073 / TR / NCATS NIH HHS / United States
P01 AG003949 / AG / NIA NIH HHS / United States
P01 AG03949 / NH / NIH HHS / United States