Collectively, the development of anxiety during stress was caused by microglial recruitment of IL-1β-producing monocytes, which stimulated brain endothelial IL-1R1.
Compared to their saline controls, the exposed WT mice were significantly more active in the Open Field, and the IL-1R1 KO strain showed reduced anxiety in the Zero Maze Test.
Correlation analysis between HADS score and cytokine serum levels revealed positive associations of anxiety and/or depression with IL-1β, IL-6, IL-8, and TNF-α, and a negative correlation with IL-10, suggesting that cytokines are involved in the pathophysiology of these psychological disorders in CRC patients.
In contrast, obese patients diagnosed with anxiety or mood disorders only showed significantly lower expression levels of IL1B in VAT and ADIPOQ in SAT when compared with obese subjects without mental disorders.
Moreover, the monocytes recruited to the brain and associated with the development of anxiety had a transcriptional signature (enhanced IL-1β, CD14, Mmp9, Myd88, Ager, and Stat3) that was dependent on IL-6.
Our results demonstrated that IL-1β knock-down in the hippocampus significantly attenuated the memory deficits and anxiety- and depression-like behaviors induced by LPS in mice.
Patients who were symptomatic had the highest depression and anxiety scores, together with increased intestinal expression of IL-1β, IL-6 and matrix metalloproteinase-9, increased circulating IL-6 and CRP, and an increased circulating kynurenine:tryptophan ratio.
Strong statistical evidence was provided for interactions between: 1) IL-1β (rs1143634) and fear of pain for predicting loss of shoulder flexion and abduction, 2) IL-1β (rs1143634) and anxiety for predicting loss of flexion, and 3) IL-1β (rs1143634) and depressive symptoms for predicting loss of internal rotation.