Abstract
The protection of cells in the upper intestine against digestion by pancreatic trypsin depends on the prostanoid prostaglandin E2 (PGE2) and is mediated by protease-activated receptors in the epithelium1,2. As the airway epithelium is morphologically similar and also expresses one of these receptors, PAR2 (ref. 3), and is a major source of PGE2 (ref. 4), we reasoned that bronchial epithelial PAR2 might also participate in prostanoid-dependent cytoprotection in the airways. Here we show that activation of PAR2, which co-localizes immunohistochemically with trypsin(ogen) in airway epithelium, causes the relaxation of airway preparations from mouse, rat, guinea-pig and humans by the release of a cyclooxygenase product from the epithelium. This physiological protective response in isolated airways also occurred in anaesthetized rats, where activation of PAR2 caused a marked and prolonged inhibition of bronchoconstriction. After desensitization of PAR2, the response to trypsin recovered rapidly by mechanisms dependent on de novo synthesis and trafficking of proteins. Our results indicate that trypsin released from the epithelium can initiate powerful bronchoprotection in the airways by activation of epithelial PAR2.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout





Similar content being viewed by others
References
Déry, O., Corvera, C. U., Steinhoff, M. & Bunnett, N. Proteinase-activated receptors: novel mechanisms of signaling by serine proteases. Am. J. Physiol. 274 43, C1429–C1452 (1998).
Kong, W. et al. Luminal trypsin may regulate enterocytes through proteinase-activated receptor-2. Proc. Natl Acad. Sci. USA 94, 8884–8889 (1997).
D'Andrea, M. R. et al. Characterization of proteinase-activated receptor-2 immunoreactivity in normal human tissues. J. Histochem. Cytochem. 46, 157–164 (1998).
Pavord, I. D. & Tattersfield, A. E. Bronchoprotective role for endogenous prostaglandin E2. Lancet 344, 436–438 (1994).
Vu, T.-K., Hung, D., Wheaton, V. I. & Coughlin, S. R. Molecular cloning of a functional thrombin receptor reveals a novel proteolytic mechanism of receptor activation. Cell 64, 1057–1068 (1991).
Ishihara, H. et al. Protease-activated receptor 3 is a second thrombin receptor in humans. Nature 386, 502–506 (1997).
Xu, W.-F. et al. Cloning and characterization of human protease-activated receptor-4. Proc. Natl Acad. Sci. 95, 6642–6646 (1998).
Nystedt, S., Emilsson, K., Wahlestedt, C. & Sundelin, J. Molecular cloning of a potential proteinase activated receptor. Proc. Natl Acad. Sci. USA 91, 8208–9212 (1994).
Böhm, S. K. et al. Molecular cloning, expression and potential functions of the human proteinase-activated receptor-2. Biochem. J. 314, 1009–1016 (1996).
Kahn, M. L. et al. Adual thrombin receptor system for platelet activation. Nature 394, 690–694 (1998).
Coughlin, S. R. Thrombin receptor function and cardiovascular disease. Trends Cardiovasc. Med. 4, 77–83 (1994).
Blackhart, B. D. et al. Ligand cross-reactivity within the protease-activated receptor family. J. Biol. Chem. 271, 16466–16471 (1996).
Molino, M. et al. Endothelial cell thrombin receptors and PAR-2: Two protease-activated receptors located in a single cellular environment. J. Biol. Chem. 272, 11133–11141 (1997).
Moncada, S., Palmer, R. M. J. & Higgs, E. A. Nitric oxide: physiology, pathophysiology, and pharmacology. Pharmacol. Rev. 43, 109–142 (1991).
Kemp, B. K. & Cocks, T. M. Evidence that mechanisms dependent and independent of nitric oxide mediate endothelium-dependent relexation to bradykinin in human small resistance-like arteries. Br. J. Pharmacol. 120, 757–762 (1997).
Böhm, S. K. et al. Mechanisms of densitization and resensitization of proteinase-activated receptor-2. J. Biol. Chem. 271, 22003–22016 (1996).
Szarek, J. L., Spurlock, B., Gruetter, C. A. & Lemke, S. Substance P and capsaicin release prostaglandin E2from intrapulmonary bronchi. Am. J. Physiol. 275, L1006–L1012 (1998).
Manning, P. J., Jones, G. L. & O'Byrne, P. M. Tachyphylaxis to inhaled histamine in asthmatic subjects. J. Appl. Physiol. 64, 1572–1577 (1987).
O'Byrne, P. M. & Jones, G. L. The effect of indomethacin on exercise-induced bronchoconstriction and refractoriness after exercise. Am. Rev. Respir. Dis. 134, 69–72 (1986).
Choudry, N. B., Fuller, R. W. & Pride, N. B. Sensitivity of the human cough reflex: effect of inflammatory mediators prostaglandin E2, bradykinin, and histamine. Am. Rev. Respir. Dis. 140, 137–141 (1989).
Kawano, N. et al. Expression of gelatinase A, tissue inhibitor of metalloproteinases-2, matrilysin, and trypsin(ogen) in lung neoplasms: an immunohistochemical study. Human Pathol. 28, 613–622 (1997).
Weidemann, H. P. & Stoller, J. K. Lung disease due to α1-antitrypsin deficiency. Curr. Opin. Pulm. Med. 2, 155–160 (1996).
Acknowledgements
This work was supported by the NHMRC of Australia. We thank V. Sozzi and J.Rogers for technical assistance; J. Morrison, M. O'Bryan, B. Major and S. Selemidis for help with in situ hybridization and for comments; N. Bunnett for mouse PAR2 antibody; A. Hughes and A. Hunt-Sturman for synthesis of some of the peptides; and J. Tatoulis and staff of the Royal Melbourne Hospital, Melbourne for their help in obtaining preparations of human airway and financial support for J.D.M.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Cocks, T., Fong, B., Chow, J. et al. A protective role for protease-activated receptors in the airways. Nature 398, 156–160 (1999). https://doi.org/10.1038/18223
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/18223
This article is cited by
-
Protease-activated receptors (PARs): mechanisms of action and potential therapeutic modulators in PAR-driven inflammatory diseases
Thrombosis Journal (2019)
-
From engineering to editing the rat genome
Mammalian Genome (2017)
-
Topical glucocorticoid or pimecrolimus treatment suppresses thymic stromal lymphopoietin-related allergic inflammatory mechanism in an oxazolone-induced atopic dermatitis murine model
Archives of Dermatological Research (2015)
-
Pseudomonas aeruginosa elastase causes transient disruption of tight junctions and downregulation of PAR-2 in human nasal epithelial cells
Respiratory Research (2014)
-
Differences in PAR-2 activating potential by king crab (Paralithodes camtschaticus), salmon (Salmo salar), and bovine (Bos taurus) trypsin
BMC Research Notes (2013)