Sessions

Chronic enteritis in dogs is a globally widespread disease. The condition is generally associated with disruption of the animals’ healthy gut microbiota and the continuous release of endotoxins produced by overgrown pathogenic bacteria. In chronic enteropathy, damage to the intestinal wall integrity allows endotoxins to enter the systemic circulation, which not only contributes to the exacerbation of gastrointestinal symptoms through increased oxidative stress and persistent inflammation, but may also lead to the development of systemic complications over the long term. Curcumin and fumaric acid are natural, plant-derived compounds with antioxidant and anti-inflammatory properties and may therefore serve as useful adjunct therapeutic agents in chronic enteropathies.

In our study, peripheral blood mononuclear cells (PBMCs) were placed on microtiter plates, and treated with E. coli O111:B4 and Salmonella Typhimurium LPS to model systemic endotoxin exposure. Subsequently, fumaric acid was added at concentrations of 12.5 and 50 μg/ml, and curcumin at 6.25 and 25 μg/ml. Intracellular reactive oxygen species (ROS) levels were determined with the DCFH-DA assay, and tumor necrosis factor- α (TNF-α) levels were measured by ELISA. The minimum inhibitory concentration (MIC) and mutant prevention concentration (MPC) of curcumin and fumaric acid against E. coli were determined, and their interactions with amoxicillin–clavulanic acid, gentamicin, and enrofloxacin were evaluated. The treatments significantly reduced LPS-induced inflammation and oxidative stress, as reflected by markedly lower intracellular ROS and TNF-α levels. Although the compounds did not show significant antibacterial activity on their own, curcumin exhibited a synergistic effect with amoxicillin–clavulanic acid.

Based on our results, fumaric acid and curcumin may exert beneficial effects in chronic intestinal disease in dogs. They can help mitigate inflammation sustained by endotoxemia, contribute to the restoration of a healthy gut microbiota, and potentially reduce the need for antibiotics in chronic enteropathies. Further in vitro and in vivo studies are required before clinical application.