THE BIOFLAVONOID FUSTIN ISOLATED FROM COTINUS COGGYGRIA HEARTWOOD ALLEVIATES TRINITROBENZENESULFONIC ACID-INDUCED COLITIS IN RATS BY SUPPRESSION OF NF-κB SIGNALLING PATHWAYS

PURPOSE: To assess the impact of 20 mg/kg orally administered fustin on colon histology and immunohistochemical expression of nuclear factor kappa B (NF-κB) in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis model in rats. METHODS: Cotinus coggygria heartwood was used to obtain fustin and then the substance was purified. There were three groups of Wistar rats – Control, TNBS and TNBS+F20. To induce colitis, 10 mg TNBS was applied rectally. Control rats were applied saline rectally. Fustin (20 mg/kg) was administered daily orally for 8 days to animals from TNBS+F20 group while the other groups received the vehicle for fustin. At the end of the experiment, colon samples were collected and the histological changes in the colon were investigated under light microscopy after staining with hematoxylin-eosin. Polyclonal antibodies were utilized to determine the expression of NF-κB immunohistochemically. RESULTS: In the TNBS group, histological analysis revealed widespread epithelial destruction, inflammatory infiltration throughout all layers of the colon wall, and localized oedema, along with a significant increase in cytoplasmic NF-κB expression compared to the Control group (p<0.001 vs. Control). Fustin treatment significantly lowered the microscopic scores for epithelial destruction (p<0.001 vs. TNBS), colonic inflammatory infiltration (p<0.01 vs. TNBS), and oedema (p<0.01 vs. TNBS). Additionally, immunohistochemical expression of NF-κB was notably reduced in the fustin-treated group (p<0.001 vs. TNBS). CONCLUSIONS: The Cotinus coggygria-derived flavonoid fustin, orally administered at a dose of 20 mg/kg, was effective in mitigating the microscopic and immunohistochemical signs of TNBS-induced colitis.