Neuroinflammation: An Integrating Overview of Reactive-Neuroimmune Cell Interactions in Health and Disease

Figure 1

Essential ways cytokines affect the brain. (1) De novo synthesis of cytokines in the CNS in homeostatic conditions is clear. (2) Peripheral cytokines can induce brain cytokine synthesis. Also, cytokines can act centrally via endothelial cells. Cytokine-endothelial cell interaction triggers the release of second messengers like nitric oxide (NO) and prostaglandins (PGS) with central effects. Hence, the signal mediated by a cytokine as IL-1β can be transduced from the periphery without crossing the BBB. (3) Systemic administration of IL-1β and TNF-α to experimental animals decreases BBB selectivity. Cytokines induce glial stimulation.