TY - JOUR
T1 - Protease-activated receptor-2 in endosomes signals persistent pain of irritable bowel syndrome
AU - Jimenez-Vargas, Nestor N.
AU - Pattison, Luke A.
AU - Zhao, Peishen
AU - Lieu, Tina Marie
AU - Latorre, Rocco
AU - Jensen, Dane D.
AU - Castro, Joel
AU - Aurelio, Luigi
AU - Le, Giang T.
AU - Flynn, Bernard
AU - Herenbrink, Carmen Klein
AU - Yeatman, Holly R.
AU - Edgington-Mitchell, Laura
AU - Porter, Christopher J.H.
AU - Halls, Michelle L.
AU - Canals, Meritxell
AU - Veldhuis, Nicholas A.
AU - Poole, Daniel P.
AU - McLean, Peter
AU - Hicks, Gareth A.
AU - Scheff, Nicole
AU - Chen, Elyssa
AU - Bhattacharya, Aditi
AU - Schmidt, Brian L.
AU - Brierley, Stuart M.
AU - Vanner, Stephen J.
AU - Bunnett, Nigel W.
N1 - Publisher Copyright:
© 2018 National Academy of Sciences. All rights reserved.
PY - 2018/7/31
Y1 - 2018/7/31
N2 - Once activated at the surface of cells, G protein-coupled receptors (GPCRs) redistribute to endosomes, where they can continue to signal. Whether GPCRs in endosomes generate signals that contribute to human disease is unknown. We evaluated endosomal signaling of protease-activated receptor-2 (PAR2), which has been proposed to mediate pain in patients with irritable bowel syndrome (IBS). Trypsin, elastase, and cathepsin S, which are activated in the colonic mucosa of patients with IBS and in experimental animals with colitis, caused persistent PAR2-dependent hyperexcitability of nociceptors, sensitization of colonic afferent neurons to mechanical stimuli, and somatic mechanical allodynia. Inhibitors of clathrin- and dynamin-dependent endocytosis and of mitogen-activated protein kinase kinase-1 prevented trypsin-induced hyperexcitability, sensitization, and allodynia. However, they did not affect elastase- or cathepsin S-induced hyperexcitability, sensitization, or allodynia. Trypsin stimulated endocytosis of PAR2, which signaled from endosomes to activate extracellular signal-regulated kinase. Elastase and cathepsin S did not stimulate endocytosis of PAR2, which signaled from the plasma membrane to activate adenylyl cyclase. Biopsies of colonic mucosa from IBS patients released proteases that induced persistent PAR2-dependent hyperexcitability of nociceptors, and PAR2 association with β-arrestins, which mediate endocytosis. Conjugation to cholestanol promoted delivery and retention of antagonists in endosomes containing PAR2. A cholestanol-conjugated PAR2 antagonist prevented persistent trypsin- and IBS protease-induced hyperexcitability of nociceptors. The results reveal that PAR2 signaling from endosomes underlies the persistent hyperexcitability of nociceptors that mediates chronic pain of IBS. Endosomally targeted PAR2 antagonists are potential therapies for IBS pain. GPCRs in endosomes transmit signals that contribute to human diseases.
AB - Once activated at the surface of cells, G protein-coupled receptors (GPCRs) redistribute to endosomes, where they can continue to signal. Whether GPCRs in endosomes generate signals that contribute to human disease is unknown. We evaluated endosomal signaling of protease-activated receptor-2 (PAR2), which has been proposed to mediate pain in patients with irritable bowel syndrome (IBS). Trypsin, elastase, and cathepsin S, which are activated in the colonic mucosa of patients with IBS and in experimental animals with colitis, caused persistent PAR2-dependent hyperexcitability of nociceptors, sensitization of colonic afferent neurons to mechanical stimuli, and somatic mechanical allodynia. Inhibitors of clathrin- and dynamin-dependent endocytosis and of mitogen-activated protein kinase kinase-1 prevented trypsin-induced hyperexcitability, sensitization, and allodynia. However, they did not affect elastase- or cathepsin S-induced hyperexcitability, sensitization, or allodynia. Trypsin stimulated endocytosis of PAR2, which signaled from endosomes to activate extracellular signal-regulated kinase. Elastase and cathepsin S did not stimulate endocytosis of PAR2, which signaled from the plasma membrane to activate adenylyl cyclase. Biopsies of colonic mucosa from IBS patients released proteases that induced persistent PAR2-dependent hyperexcitability of nociceptors, and PAR2 association with β-arrestins, which mediate endocytosis. Conjugation to cholestanol promoted delivery and retention of antagonists in endosomes containing PAR2. A cholestanol-conjugated PAR2 antagonist prevented persistent trypsin- and IBS protease-induced hyperexcitability of nociceptors. The results reveal that PAR2 signaling from endosomes underlies the persistent hyperexcitability of nociceptors that mediates chronic pain of IBS. Endosomally targeted PAR2 antagonists are potential therapies for IBS pain. GPCRs in endosomes transmit signals that contribute to human diseases.
KW - Endosomes
KW - Pain
KW - Proteases
KW - Receptors
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UR - http://www.scopus.com/inward/citedby.url?scp=85051717936&partnerID=8YFLogxK
U2 - 10.1073/pnas.1721891115
DO - 10.1073/pnas.1721891115
M3 - Article
C2 - 30012612
AN - SCOPUS:85051717936
SN - 0027-8424
VL - 115
SP - E7438-E7447
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 31
ER -