UniPR1331: Small Eph/Ephrin Antagonist Beneficial in Intestinal Inflammation by Interfering with Type-B Signaling

Ephrin B3 exacerbates colitis and colitis-associated colorectal cancer

Ephrin B3, a member of Eph/ephrin family, contributes to embryogenesis and carcinogenesis, but few studies have suggested whether this ligand has regulatory effect on colitis. This study was to determine whether ephrin B3 played a role in colitis and colonic carcinogenesis. Dextran sodium sulfate (DSS)-induced colitis and azoxymethane (AOM)/DSS-induced colitis-associated carcinogenesis model was established in Efnb3-deficient (Efnb3-/-) mice. Label-free quantitative proteomics were performed to identify the Efnb3-regulated proteins. Our results showed that Efnb3 knock out reduced the symptoms of DSS-induced colitis, such as disease activity index (DAI), inflammatory factors release, and dysfunction of the intestinal barrier. Quantitative proteomics revealed that Efnb3 regulated 95 proteins which clustered in the platelet degranulation, response to elevated platelet cytosolic Ca2+, MAPK signaling for integrins such as ITGB4. Furthermore, ephrin B3 inactived ITGB4/AKT signal pathway and then promoted epithelial barrier dysfunction. Simultaneously, ephrin B3 promoted Gremlin-1/NF-κB signal pathway and thereby increased inflammatory factors release. In addition, the higher level of Efnb3 in colon cancer patients is correlated with worse survival. Efnb3-/- mice exhibited susceptibility to AOM/DSS-induced colorectal cancer. Our finding discovered that Efnb3 played an important role in the development of colitis and colitis-associated colorectal cancer. Efnb3 deficiency improved the intestinal barrier by ITGB4 and suppressed inflammation via Gremlin-1/NF-κB signal pathway, which may provide a novel therapeutic strategy for the treatment of colitis and colitis-associated colorectal cancer.

Probing the effects of MR120 in preclinical chronic colitis: A first-in-class anti-IBD agent targeting the CCL20/CCR6 axis

Concerning the growing interest in the role played by the CCL20/CCR6 axis in IBD pathogenesis and in the search for novel anti-IBD small molecules, we have recently discovered the first small-molecule (MR120) endowed with protective action against TNBS-induced colitis and zymosan-induced peritonitis. This protective action occurs through interference with the CCL20/CCR6 signaling. The aim of the present work is to expand the preclinical investigation of MR120, evaluating its beneficial anti-inflammatory effect on a model of chronic colitis obtained by cyclically exposing C57BL/6 mice to 3% DSS. Subcutaneous administration of MR120 at 1 mg/kg, the same dose effective against acute inflammation, helped attenuate several systemic and local inflammatory responses induced by DSS. Besides significantly improving murine health conditions, MR120 counteracted mucosal macroscopic injury, the increase of colonic edema and neutrophils oxidative activity, and mitigated spleen enlargement, while not significantly lowering intestinal IL-6 concentration. Overall, repeated daily treatment with MR120 for approximately 30 days was well tolerated and showed moderate protection in a relevant model of chronic colitis, in line with the beneficial effect previously observed in acute models of intestinal inflammation. Although more potent analogues of MR120 will be needed to more fully evaluate their clinical translatability, the present work provides a valuable example of in vivo efficacy of CCL20/CCR6 modulators in a chronic model of IBD.