| Objective: Crohn's disease is characterized by chronic inflammation of the gastrointestinal tract leading to fibrosis and stricture. Despite advances in immunoregulatory therapy, the pathophysiology of fibrosis and stricture formation remains poorly understood, and no treatment drugs have been developed yet. Therefore, we aimed to elucidate the pathophysiology of fibrosis and develop new treatments. Methods: We developed a new EDTA-induced intestinal fibrosis model. By injecting EDTA (ethylenediaminetetraacetic acid) into the rectum lumen and rubbing the intestinal epithelium, fibrosis was induced within a short period. We subjected this model into global gene expression analysis (bulk RNA-seq, scRNA-seq), flow cytometry, and microscopy. Results: 14 days after EDTA treatment, we successfully developed an intestinal fibrosis model with full-layer inflammation and inflammatory cell infiltration. Analysis of fibroblasts 14 days after EDTA treatment using scRNA-seq revealed the emergence of a new population of fibroblasts in the fibrosis model, characterized by high expression of Lox and Thy1. Furthermore, immunohistochemistry confirmed a significant increase in LOX (lysyl oxidase) positive fibroblasts with fibrosis at the protein level. Finally, inhibition of LOX activity by BAPN (beta-aminopropionitrile) significantly improved the mouse intestinal fibrosis model. Conclusion: We identified LOX-positive fibroblasts emerging with fibrosis and demonstrated that LOX inhibition improves intestinal fibrosis. LOX may be a potential target for suppressing or curing intestinal fibrosis and stricture in patients with Crohn's disease. |
