Sea Conch Peptides Hydrolysate Alleviates DSS-Induced Colitis in Mice through Immune Modulation and Gut Microbiota Restoration.

Inflammatory bowel disease (IBD) is a persistent, lifelong inflammation of the digestive system. Dextran sulfate sodium is commonly used to induce colitis in experimental animal models, which causes epithelial damage, intestinal inflammation, mucin depletion, and dysbiosis of the gut microbiota. Various prebiotics, polysaccharides, and polypeptides are used for IBD treatment. In this study, we used a murine model utilizing BALB/c mice, with 10 mice per group, to investigate the treatment effect of sea conch peptide hydrolysate (CPH) on DSS-induced colitis mice. Colitis was induced through the administration of 2.5% DSS in drinking water over a seven-days period. Furthermore, on the eighth day of the experiment, sea conch peptide hydrolysate (CPH) at low (100 mg/kg), medium (200 mg/kg), and high (400 mg/kg) doses, which were continued for 14 days, were assessed for medicinal purposes in DSS-induced colitis mice. Our results showed that CPH treatment significantly alleviated the severity and symptoms of colitis. The epithelial integrity and histological damage were improved. Intestinal inflammation and inflammatory cell infiltration were improved. Furthermore, the expression of pro-inflammatory cytokines was reduced, and intestinal barrier integrity was restored by elevating the tight junction proteins. Moreover, 16s RNA sequencing revealed dysbiosis of the gut microbiota was observed upon DSS treatment, which was reinstated after CPH treatment. An increased level of Firmicutes and Lactobacillus was observed in the treatment groups. Finally, our results suggest that CPH would be recommended as a functional food source and also have the potential to be used as a medicinal product for different gastrointestinal disorders.

Lactobacillus rhamnosus Attenuates Cisplatin-Induced Intestinal Mucositis in Mice via Modulating the Gut Microbiota and Improving Intestinal Inflammation.

Lactobacillus rhamnosus (LBS) is a well-documented probiotic strain in oncology and has a pivotal role in clinical applications. Here, we have investigated the protective effect of Lactobacillus rhamnosus on intestinal mucositis induced by cisplatin (CP) and explored the underlying mechanisms targeting inflammatory proteins, as well as the histological changes in the intestinal tissue of mice, in addition, the bacterial strains that may be related to the health-enhancing properties. BALB/c mice were pre-treated with or without LBS via oral gavage, followed by mucositis induction with cisplatin. Our results revealed that the LBS-treated groups significantly attenuated proinflammatory cytokine levels (IL-1ß, IL-6, and TNF-α) compared to the CP group. Furthermore, LBS mitigated the damaged tight junction integrity caused by CP via up-regulating the levels of claudin, occludin, ZO-1, and mucin-2 protein (MUC-2). Finally, the 16S rRNA fecal microbiome genomic analysis showed that LBS administration enhanced the growth of beneficial bacteria, i.e., Firmicutes and Lachnospiraceae, while the relative abundance of the opportunistic bacteria Bacteroides and Proteobacteria decreased. Collectively, LBS was found to beneficially modulate microbial composition structure and functions and enrich the ecological diversity in the gut.