Premium
Adenosine triphosphate induces P2Y2 activation and interleukin‐8 release in human esophageal epithelial cells
Author(s) -
Wu Liping,
Oshima Tadayuki,
Fukui Hirokazu,
Watari Jiro,
Miwa Hiroto
Publication year - 2017
Publication title -
journal of gastroenterology and hepatology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.214
H-Index - 130
eISSN - 1440-1746
pISSN - 0815-9319
DOI - 10.1111/jgh.13672
Subject(s) - adenosine a2b receptor , purinergic receptor , receptor , purinergic signalling , receptor antagonist , adenosine , adenosine a3 receptor , agonist , protease activated receptor 2 , interleukin 21 receptor , adenosine receptor , enzyme linked receptor , medicine , microbiology and biotechnology , biology , endocrinology , antagonist
Abstract Background and Aim Immune‐mediated mucosal inflammation characterized by the release of interleukin (IL)‐8 is associated with gastroesophageal reflux disease. ATP released by human esophageal epithelial cells (HEECs) mediates the release of cytokines through P2 nucleotide receptors that are present on various cells, including HEECs. This study characterized and identified human esophageal epithelial P2 receptors that are responsible for ATP‐mediated release of IL‐8 by using a human esophageal stratified squamous epithelial model. Methods Primary HEECs were cultured with the use of an air‐liquid interface (ALI) system. The ATP analogue adenosine 5′‐O‐3‐thiotriphosphate (ATP‐ γ ‐S) was added to the basolateral compartment, and IL‐8 release was measured. Involvement of the P2Y2 receptor was assessed with the use of selective and non‐selective receptor antagonists and a P2Y2 receptor agonist. Expression of the P2Y2 receptor was assessed using western blotting and immunohistochemistry. Results Adenosine triphosphate‐ γ ‐S induced IL‐8 release through the P2Y2 receptor. A P2Y2 receptor antagonist but not a P2X3 receptor antagonist or a P2Y1 receptor antagonist blocked ATP‐ γ ‐S‐mediated IL‐8 release. Conversely, a P2Y2 receptor agonist induced IL‐8 release. Western blotting and immunohistochemistry of the P2Y2 receptor showed strong expression of the P2Y2 receptor on ALI‐cultured HEECs and in human esophagus. Inhibition of extracellular signal‐regulated kinase but not of protein kinase C blocked the ATP‐mediated release of IL‐8. ATP‐ γ ‐S induced phosphorylation of extracellular signal‐regulated kinase, and a P2Y2 receptor antagonist blocked this phosphorylation. Conclusions Interleukin‐8 release after purinergic stimulation in ALI‐cultured HEECs is mediated through P2Y2 receptor activation. ATP‐induced IL‐8 release maybe involved in the pathogenesis of refractory gastroesophageal reflux disease.