A novel P2X2‐dependent purinergic mechanism of enteric gliosis in intestinal inflammation

Abstract

Enteric glial cells (EGC) modulate motility, maintain gut homeostasis, and contribute to neuroinflammation in intestinal diseases and motility disorders. Damage induces a reactive glial phenotype known as “gliosis”, but the molecular identity of the inducing mechanism and triggers of “enteric gliosis” are poorly understood. We tested the hypothesis that surgical trauma during intestinal surgery triggers ATP release that drives enteric gliosis and inflammation leading to impaired motility in postoperative ileus (POI). ATP activation of a p38‐dependent MAPK pathway triggers cytokine release and a gliosis phenotype in murine (and human) EGCs. Receptor antagonism and genetic depletion studies revealed P2X2 as the relevant ATP receptor and pharmacological screenings identified ambroxol as a novel P2X2 antagonist. Ambroxol prevented ATP‐induced enteric gliosis, inflammation, and protected against dysmotility, while abrogating enteric gliosis in human intestine exposed to surgical trauma. We identified a novel pathogenic P2X2‐dependent pathway of ATP‐induced enteric gliosis, inflammation and dysmotility in humans and mice. Interventions that block enteric glial P2X2 receptors during trauma may represent a novel therapy in treating POI and immune‐driven intestinal motility disorders.

Abstract

Enteric gliosis was shown to be part of an intestinal immune response upon abdominal surgery. ATP activates enteric glial cells via selective purinergic receptor signalling in mice and humans. Inhibition of this pathogenic pathway by the newly identified P2X2 antagonist ambroxol blocks ATP‐induced enteric gliosis and protects against postoperative ileus.