Higher levels of pro-inflammatory peripheral cytokines have been identified both in models of anxiety disorders (tumor necrosis factor-α [TNF-α] and interleukin [IL]-1 β, IL-6) [38,39], as well as mood and anxiety disorders patients (c-reactive protein [CRP], TNF-alpha, IL-1, IL-6,) [40,41]. Here, TNF is linked to anxiety disorder.