human umbilical cord mesenchymal stem cells-derived exosomes can alleviate the proctitis model through tlr4/nf-kb pathway

Background: proctitis is a significant concern of inflammatory bowel diseases, especially ulcerative colitis. exosomes are a new method for treating many diseases by their immunosuppressive and tissue-repairing potential. here, we tried mesenchymal stem cells (mscs)-derived exosomes for treating the proctitis model of rats. materials and methods: rats were assigned into four groups: sham, control group, rectal, and intraperitoneal exosome injection. the proctitis model was induced by rectal administration of 4% acetic acid. the exosome was derived from human mscs isolated from human umbilical cords. after seven days, rectum samples were assessed for histopathological, ihc, and pcr analysis. results: the histopathologic scores, collagen deposition, and the expression of nf-?b, tlr4, tnf?, il-6, and tgf? were decreased in intraperitoneal exosome compared to controls. the result was not promising for the rectal administration of exosomes. conclusion: exosomes can suppress the inflammatory response in the proctitis model and improve the rectum's healing process. exosomes can inhabit the nf-?b/tlr4 pathway and downstream pro-inflammatory cytokines. this study implicates the therapeutic benefits of exomes in treating proctitis.