Dual-origin probiotic formulation attenuates intestinal inflammation in experimental colitis

Intestinal inflammation associated with inflammatory bowel disease (IBD) is driven by complex interactions between host immunity and gut microbiota, necessitating alternative therapeutic strategies beyond conventional immunosuppressive drugs. In the present study, a dual-origin probiotic formulation comprising Lactobacillus plantarum AG40V (plant-derived) and Lactobacillus fermentum HO17HF (human-derived) was developed and evaluated for its safety and anti-inflammatory efficacy in a 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis model in Sprague–Dawley rats. The formulation (1012 CFU/mL; 1:1 ratio) exhibited stability under refrigerated conditions and demonstrated significant in vitro functional antioxidant activities. Acute and sub-acute oral toxicity studies, conducted in accordance with OECD guidelines, confirmed the safety of the formulation, with no mortality or significant alterations in physiological, haematological, biochemical, or histopathological parameters. In the TNBS-induced colitis model, oral administration of the probiotic formulation resulted in marked attenuation of intestinal inflammation, as evidenced by reduced levels of nitric oxide, myeloperoxidase, and lipid peroxidation, along with enhanced catalase activity. Collectively, these findings demonstrate that the dual-origin probiotic formulation is safe and functionally effective in mitigating intestinal inflammation through modulation of oxidative stress and host inflammatory responses. This study highlights the translational potential of ecologically diverse probiotic consortia as a promising strategy for the management of inflammatory gastrointestinal disorders. Key points Dual-origin probiotics showed safety in experimental colitisTreatment reduced inflammation and improved gut healthFindings support probiotic potential in inflammatory bowel disease