Brain-Spleen Inflammatory Coupling: A Literature Review

Jonathan Rasouli, Rukmani Lekhraj, Mihran Ozbalik, Parviz Lalezari, Diana Casper


Recent evidence suggests a link between brain injury and the autonomic release of pro-inflammatory cytokines by resident macrophages in the spleen. This phenomenon, termed “brainspleen inflammatory coupling,” has garnered attention from scientific and medical communities interested in developing novel treatments for traumatic brain injury (TBI). Cholinergic stimulation of the α7-subunit nicotinic acetylcholine receptor (α7NAchR) on splenic macrophages has been shown to
inhibit their release of pro-inflammatory cytokines. This inhibition, mediated by the parasympathetic nervous system, has been shown to improve outcomes in animal models of sepsis, stroke, and TBI. As evidence of a beneficial role of splenic inhibition grows, new treatment strategies might be applied to many medical conditions involving neuroinflammation, a process that contributes to further neurological deterioration.


brain injury; spleen; inflammation

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