Protective mechanism of butyrate and palmitoylethanolamide highlighted by VitroScreen ORA® - a new microphysiological system mimicking colon inflammation

Abstract

The incidence and prevalence of inflammatory bowel disease (IBD) continues to increase worldwide. Furthermore, a considerable fraction of individuals with IBD do not respond effectively to conventional treatments, suggesting a need for new therapeutic strategies. Butyrate and palmitoylethanolamide (PEA) are individually recognised for their protective effect on the gut epithelial permeability barrier. In this study, VitroScreen ORA™ intestinal 3D scaffold-free spheroids were used to mirror in vitro a model of an inflamed colonic epithelium and to investigate, in a preliminary setting, the protective mechanisms of a synergistic blend of butyrate and PEA. Spheroids were produced using human colonic fibroblasts and primary epithelial colonic cells. Differentiated spheroids were pretreated with either mesalamine, butyrate, PEA, or a blend of butyrate and PEA in a 3:1 ratio. To evaluate the protective effect of these molecules, a stimulation with interleukin 1β or with dextran sodium sulfate was applied to induce a pro-inflammatory status and epithelial damage respectively. ELISA assay and immunohistochemical techniques were used to detect the inflammatory status and epithelium integrity. Butyrate mitigated the expression and release of interleukin-1β while PEA increased zonula occludens-1 expression. Treatment with the blend consisting of butyrate and PEA showed a synergistic effect on tight junctions in terms of zonula occludens-1 increased expression and improved localization. Our preliminary data are promising, suggesting an application of ORA™ intestinal spheroids as an innovative platform with the ability to mirror gut inflammatory status. Furthermore, the results suggest a novel application of butyrate and PEA in clinical practice to better manage pathogenesis and flare-ups of IBD.