Multi-Strain-Probiotic-Loaded Nanoparticles Reduced Colon Inflammation and Orchestrated the Expressions of Tight Junction, NLRP3 Inflammasome and Caspase-1 Genes in DSS-Induced Colitis Model.

Gut modulation by multi-strain probiotics (MSPs) is considered an effective strategy for treating inflammatory bowel disease (IBD). The combination of nanomaterial-based MSPs can improve their viability and resistance and can allow their targeted release in the gastrointestinal tract to be achieved. Thus, our aim is to investigate the prospective role of MSP integration into nanomaterials (MSPNPs) and the underlying molecular mechanisms supporting their application as an alternative therapy for IBD using a colitis rat model. To induce the colitis model, rats received 5% DSS, and the efficacy of disease progression after oral administration of MSPNPs was assessed by evaluating the severity of clinical signs, inflammatory response, expressions of tight-junction-related genes and NLRP3 inflammasome and caspase-1 genes, microbial composition and histopathological examination of colonic tissues. The oral administration of MSPNPs successfully alleviated the colonic damage induced by DSS as proved by the reduced severity of clinical signs and fecal calprotectin levels. Compared with the untreated DSS-induced control group, the high activities of colonic NO and MPO and serum CRP levels were prominently reduced in rats treated with MSPNPs. Of note, colonic inflammation in the group treated with MSPNPs was ameliorated by downstreaming NLRP3 inflammasome, caspase-1, IL-18 and IL-1β expressions. After colitis onset, treatment with MSPNPs was more effective than that with free MSPs in restoring the expressions of tight-junction-related genes (upregulation of occludin, ZO-1, JAM, MUC and FABP-2) and beneficial gut microbiota. Interestingly, treatment with MSPNPs accelerated the healing of intestinal epithelium as detected in histopathological findings. In conclusion, the incorporation of MPSs into nanomaterials is recommended as a perspective strategy to overcome the challenges they face and augment their therapeutic role for treating of colitis.