The Relation of Severity of Depressive Symptoms to Monocyte-Associated Proinflammatory Cytokines and Chemokines in Apparently Healthy Men

Abstract

We examined the relation of severity of depressive symptoms to lipopolysaccharide-stimulated expression of monocyte-associated proinflammatory cytokines and chemokines in 53 nonsmoking, healthy men. Assessments of cytokine and chemokine expression and severity of depressive symptoms were conducted on the same day. The 21-item Beck Depression Inventory (BDI) was used to assess severity of depressive symptoms experienced during the week before study participation. Dual-color flow cytometry was used to determine monocyte-associated (CD14+) expression of interleukin-1α (IL-1α), IL-1β, tumor necrosis factor-α (TNF-α), IL-8, and monocyte chemotactic protein-1 (MCP-1) after in vitro lipopolysaccharide stimulation of undiluted whole blood. Calculations of partial correlation coefficients controlling for age, race, body mass index, and alcohol use indicated that BDI score was significantly associated with IL-1α (r = 0.27), IL-1β (r = 0.44), TNF-α (r = 0.57), MCP-1 (r = 0.52), and IL-8 (r = 0.33). In addition, relative to men with BDI scores below 10, men with BDI scores of 10 or above exhibited an overexpression of IL-1β (p = .004), TNF-α (p = .005), IL-8 (p = .002), and MCP-1 (p = .025). Relative to men with no or minimal symptoms of depression, men with mild to moderate levels of depressive symptoms showed overexpression of monocyte-associated proinflammatory cytokines and chemokines.