Amelioration of dextran sulfate sodium-induced colitis by autoinducer-2-deficient Lactiplantibacillus plantarum is mediated by anti-inflammatory effects and alleviation of dysbiosis of the gut microbiota

Lactobacillus salivarius alleviated dextran sulfate sodium (DSS)-induced colitis in mice by mitigating oxidative stress and inflammatory responses through modulation of the intestinal flora

Colitis is a multifactorial inflammatory bowel disease (IBD) involving intestinal barrier dysfunction, immune dysregulation, oxidative stress, and microbiota imbalance. Lactobacillus salivarius (L. salivarius), a probiotic with antioxidative and anti-inflammatory properties, was evaluated in a mouse model of DSS-induced colitis. Treatment with L. salivarius significantly reduced weight loss, colon shortening, and disease activity index, while improving histopathological damage. DSS-induced colitis exhibited significant oxidative stress, evidenced by decreased total antioxidant capacity, increased malondialdehyde (MDA), and reduced activity of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). After the intervention of L. salivarius, MDA levels in colon tissues decreased significantly, while SOD and GSH-Px activities increased significantly. In DSS-induced colitis models, the expression of pro-inflammatory cytokines (such as TNF-α, IL-6, IL-1β) was significantly increased, while the expression of anti-inflammatory cytokine IL-10 was decreased. After the intervention of L. salivarius, the level of proinflammatory factors was significantly down-regulated, while the level of IL-10 was up-regulated. DSS treatment leads to a significant imbalance in the intestinal microbiota, characterized by an increase in the ratio of Firmicutes to Bacteroidetes (F/B ratio). The abundance of pathogenic bacteria (Alistipes, Candidatus_Soleaferrea, Frisingicoccus, Romboutsia, Streptococcus) increased, while beneficial bacteria (Anaerotruncus, Rikenella) decreased. After probiotic administration, the F/B ratio was restored significantly, and the abundance of important beneficial bacteria increased while the abundance of pathogenic bacteria decreased. These results suggest that L. salivarius alleviates DSS-induced colitis by enhancing antioxidant defense, regulating inflammatory responses, and restoring gut microbiota balance. This probiotic may offer a promising therapeutic strategy for managing ulcerative colitis (UC).

Lactobacillus johnsonii GLJ001 prevents DSS-induced colitis in mice by inhibiting M1 macrophage polarization via gut microbiota-SCFAs axis

Inflammatory Bowel Disease (IBD) is increasing worldwide and has become a global emergent disease. Probiotics have been reported to be effective in relieving colitis. Previous studies found ripened Pu-erh tea (RPT) promoted gut microbiota resilience against dextran sulfate sodium (DSS)-induced colitis in mice by increasing relative abundance of Lactobacillus. However, whether and how it alleviated DSS-induced colitis in mice need to be explored. Here, we screened a probiotic Lactobacillus johnsonii GLJ001 from feces of ripened Pu-erh tea (RPT)-administrated mice. In this study, L. johnsonii GLJ001 attenuated symptoms of DSS-induced colitis in mice, including weight loss, increased disease activity index (DAI), colon shortening and colon tissue damage, as well as high expression of inflammatory cytokines and disturbances of intestine barrier function. Furthermore, abundances of short-chain fatty acids (SCFAs)-producing bacteria (i.e. Clostridium cluster IV and XIVa, Lachnospiracea_incertae_sedis and Ruminococcus) were enhanced in the cecum of mice treated with L. johnsonii GLJ001, accompanying by an increase of SCFAs. It was also found that SCFAs inhibited mRNA expression of M1 macrophage markers (Inos and CD86), inflammatory cytokines (TNF-α and Il-1β) and SCFAs receptors (Gpr41 and Gpr43) induced by lipopolysaccharide (LPS) and interferon-γ (IFN-γ) in THP-1 cell line. Collectively, L. johnsonii GLJ001 prevented DSS-induced colitis in mice by inhibiting M1 macrophage polarization via gut microbiota-SCFAs axis, and can be administered for management of colitis.

Evaluation of the Effect of Probiotic Supplementation on Intestinal Barrier Integrity and Epithelial Damage in Colitis Disease: A Systematic Review

CONTEXT

Previous reviews have focused on the effects of probiotics on colitis, but there is a need to understand their impact on barrier integrity and tight junction protein improvement in colitis.

OBJECTIVE

This study aimed to systematically examine the effects of probiotic use on barrier integrity in colitis disease. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

DATA SOURCES

A systematic search in PubMed, Web of Science, Scopus, and Cochrane databases identified 2537 articles.

DATA EXTRACTION

As a result of the search, 2537 articles were accessed. Study results were summarized descriptively through discussions by intervention conditions, study population, measurement methods, and key findings. The included studies were independently reviewed and all authors reached consensus on the quality and major findings from the included articles. Forty-six studies that met the inclusion criteria were analyzed within the scope of the systematic review.

RESULTS

Although the study primarily utilized probiotics from the Lactobacillaceae family (notably, L casei, L reuteri, L rhamnosus, L plantarum, and L pentosus) and the Bifidobacteriaceae family (notably, B breve, B animalis, and B dentium), other probiotics also demonstrated positive effects on tight junction proteins. These effects are attributed to the production of bioactive and metabolic compounds, as well as short-chain fatty acids, which combat pathogens and reduce anti-inflammatory agents. However, it was observed that the effects of these probiotics on tight junction proteins varied depending on the strain and dose.

CONCLUSION

The beneficial effects of probiotics on remission in inflammatory bowel disease are well documented. Studies show that probiotics generally improve intestinal barrier function, but factors such as dose, duration, and bacterial species combinations need further clarification. Additionally, comprehensive studies are needed to understand how improved barrier function affects absorption in individuals.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023452774.

Wheat peptide alleviates DSS-induced colitis by activating the Keap1-Nrf2 signaling pathway and maintaining the integrity of the gut barrier

Inflammatory bowel disease (IBD) is difficult to cure, and formulating a dietary plan is an effective means to prevent and treat this disease. Wheat peptide contains a variety of bioactive peptides with anti-inflammatory and antioxidant functions. The results of this study showed that preventive supplementation with wheat peptide (WP) can significantly alleviate the symptoms of dextran sulfate sodium (DSS)-induced colitis in mice. WP can increase body weight, alleviate colon shortening, and reduce disease activity index (DAI) scores. In addition, WP improved intestinal microbial disorders in mice with colitis. Based on LC-MS, a total of 313 peptides were identified in WP, 4 of which were predicted to be bioactive peptides. The regulatory effects of WP and four bioactive peptides on the Keap1-Nrf2 signaling pathway were verified in Caco-2 cells. In conclusion, this study demonstrated that WP alleviates DSS-induced colitis by helping maintain gut barrier integrity and targeting the Keap1-Nrf2 axis; these results provided a rationale for adding WP to dietary strategies to prevent IBD.

Lactiplantibacillus plantarum HY7718 Improves Intestinal Integrity in a DSS-Induced Ulcerative Colitis Mouse Model by Suppressing Inflammation through Modulation of the Gut Microbiota

Inflammatory bowel disease (IBD), a chronic condition that causes persistent inflammation in the digestive system, is closely associated with the intestinal microbiome. Here, we evaluated the effects of Lactiplantibacillus plantarum HY7718 (HY7718) on IBD symptoms in mice with dextran sulfate sodium (DSS)-induced colitis. Oral administration of HY7718 led to significant improvement in the disease activity index score and the histological index, as well as preventing weight loss, in model mice. HY7718 upregulated the expression of intestinal tight junction (TJ)-related genes and downregulated the expression of genes encoding pro-inflammatory cytokines and genes involved in the TLR/MyD88/NF-κB signaling pathway. Additionally, HY7718 reduced the blood levels of pro-inflammatory cytokines, as well as reversing DSS-induced changes to the composition of the intestinal microbiome. HY7718 also increased the percentage of beneficial bacteria (Lactiplantibacillus and Bifidobacterium), which correlated positively with the expression of intestinal TJ-related genes. Finally, HY7718 decreased the population of pathogens such as Escherichia, which correlated with IBD symptoms. The data suggest that HY7718 improves intestinal integrity in colitis model mice by regulating the expression of TJ proteins and inflammatory cytokines, as well as the composition of the intestinal microflora. Thus, L. plantarum HY7718 may be suitable as a functional supplement that improves IBD symptoms and gut health.

Probiotics for the treatment of ulcerative colitis: a review of experimental research from 2018 to 2022

Ulcerative colitis (UC) has become a worldwide public health problem, and the prevalence of the disease among children has been increasing. The pathogenesis of UC has not been elucidated, but dysbiosis of the gut microbiota is considered the main cause of chronic intestinal inflammation. This review focuses on the therapeutic effects of probiotics on UC and the potential mechanisms involved. In animal studies, probiotics have been shown to alleviate symptoms of UC, including weight loss, diarrhea, blood in the stool, and a shortened colon length, while also restoring intestinal microecological homeostasis, improving gut barrier function, modulating the intestinal immune response, and attenuating intestinal inflammation, thereby providing theoretical support for the development of probiotic-based microbial products as an adjunctive therapy for UC. However, the efficacy of probiotics is influenced by factors such as the bacterial strain, dose, and form. Hence, the mechanisms of action need to be investigated further. Relevant clinical trials are currently lacking, so the extension of animal experimental findings to clinical application requires a longer period of consideration for validation.