AUTHOR=Van Spaendonk Hanne , Ceuleers Hannah , Smet Annemieke , Berg Maya , Joossens Jurgen , Van der Veken Pieter , Francque Sven M. , Lambeir Anne-Marie , De Man Joris G. , De Meester Ingrid , Augustyns Koen , De Winter Benedicte Y.
TITLE=The Effect of a Novel Serine Protease Inhibitor on Inflammation and Intestinal Permeability in a Murine Colitis Transfer Model
JOURNAL=Frontiers in Pharmacology
VOLUME=12
YEAR=2021
URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2021.682065
DOI=10.3389/fphar.2021.682065
ISSN=1663-9812
ABSTRACT=Background: A protease/antiprotease disbalance is observed in inflammatory bowel diseases (IBD). We therefore studied the effect of the novel serine protease inhibitor UAMC-00050 on intestinal inflammation and permeability in a chronic colitis T cell transfer mouse model to get further insight into the regulation of T cell-mediated immunopathology.
Methods: Colitis was induced in severe combined immunodeficient (SCID) mice, by the adoptive transfer of CD4+CD25−CD62L+ T cells. Animals were treated intraperitoneally (i.p.) 2x/day with vehicle or UAMC-00050 (5 mg/kg) from week 2 onwards. Colonic inflammation was assessed by clinical parameters, colonoscopy, macroscopy, microscopy, myeloperoxidase activity and cytokine expression levels. At week 4, 4 kDa FITC-dextran intestinal permeability was evaluated and T helper transcription factors, protease-activated receptors and junctional proteins were quantified by RT-qPCR.
Results: Adoptive transfer of CD4+CD25−CD62L+ T cells resulted in colonic inflammation and an altered intestinal permeability. The serine protease inhibitor UAMC-00050 ameliorated both the inflammatory parameters and the intestinal barrier function. Furthermore, a decrease in colonic mRNA expression of Tbet and PAR4 was observed in colitis mice after UAMC-00050 treatment.
Conclusion: The beneficial effect of UAMC-00050 on inflammation was apparent via a reduction of Tbet, IFN-γ, TNF-α, IL-1β and IL-6. Based on these results, we hypothesize a pivotal effect of serine protease inhibition on the Th1 inflammatory profile potentially mediated via PAR4.