The Impact of Dietary Interventions on the Microbiota in Inflammatory Bowel Disease: A Systematic Review

Biomarkers of Intestinal Permeability Are Influenced by Diet in Patients with Ulcerative Colitis-An Exploratory Study

Background and Objectives: The disruption of the intestinal epithelial barrier leads to increased intestinal permeability (IP), allowing endotoxins and pathogens to enter the bloodstream contributing to chronic inflammation. Western diets are associated with increased IP, while diets rich in polyphenols, fiber, and omega-3 fats are linked to decreased IP. The relationship between diet, disease activity, and IP in ulcerative colitis (UC) is poorly understood. We evaluated the effects of serum zonulin and lipopolysaccharide-binding protein (LBP) and their relationship to dietary factors in UC. Methods: A cross-sectional analysis was conducted on 37 UC participants who had baseline measures of dietary intake, disease activity and serum. Serum LBP and zonulin levels were measured by ELISA. Spearman's rank correlations explored relationships between baseline IP, diet, and disease activity. Results: The median age was 35 years (29-47 years), 54% were male, and 76% were in clinical remission or had mild disease activity (partial Mayo score ≤ 4). LBP was significantly correlated (p < 0.05) with disease activity (partial Mayo score (r = 0.31), and positively correlated with total fat (r = 0.42) and refined grains (r = 0.35), but negatively correlated with fruit consumption (r = -0.50) and diet quality (r = -0.33). Zonulin was negatively correlated with protein (r = -0.39), niacin (r = -0.52) and vitamin B12 (r = -0.45) with a trend for significance (p = 0.06) with body mass index (r = 0.32). Conclusions: Baseline LBP levels were correlated with disease activity markers and dietary factors, suggesting that it could be a useful biomarker for assessing disease activity and diet quality in UC. Further trials are needed to confirm these findings.

Healing from Within: How Gut Microbiota Predicts IBD Treatment Success-A Systematic Review

Recent research indicates that the microbiome has a significant impact on the progression of inflammatory bowel disease (IBD) and that creating therapies that change its composition could positively impact the outcomes of IBD treatment. This review summarizes the results of extensive studies that examined IBD patients undergoing several therapies, including anti-TNF medication, vedolizumab, ustekinumab, probiotics, and fecal microbiota transplantation (FMT), and the alterations in their gut microbiota's composition and function. The objective was to investigate the variety and effectiveness of microbial species in order to discover new biomarkers or therapeutic targets that could improve the outcome of treatment for these patients. This research aimed to offer useful insights into personalized medicine techniques for managing IBD. Beneficial bacteria such as Faecalibacterium prausnitzii and Roseburia have been consistently linked to favorable clinical outcomes, whereas pathogenic bacteria such as Escherichia coli and Clostridioides difficile are associated with worsening disease conditions. Although many studies have examined the role of gut microbiota in IBD, there is still a need for more targeted research on the connection between specific microbial communities and treatment outcomes. This study sought to address this gap by exploring the intricate relationship between the gut microbiota composition and the effectiveness of IBD medications.

How the Western Diet Thwarts the Epigenetic Efforts of Gut Microbes in Ulcerative Colitis and Its Association with Colorectal Cancer

Ulcerative colitis (UC) is an autoimmune disease in which the immune system attacks the colon, leading to ulcer development, loss of colon function, and bloody diarrhea. The human gut ecosystem consists of almost 2000 different species of bacteria, forming a bioreactor fueled by dietary micronutrients to produce bioreactive compounds, which are absorbed by our body and signal to distant organs. Studies have shown that the Western diet, with fewer short-chain fatty acids (SCFAs), can alter the gut microbiome composition and cause the host's epigenetic reprogramming. Additionally, overproduction of H2S from the gut microbiome due to changes in diet patterns can further activate pro-inflammatory signaling pathways in UC. This review discusses how the Western diet affects the microbiome's function and alters the host's physiological homeostasis and susceptibility to UC. This article also covers the epidemiology, prognosis, pathophysiology, and current treatment strategies for UC, and how they are linked to colorectal cancer.

Mannose enhances intestinal immune barrier function and dextran sulfate sodium salt-induced colitis in mice by regulating intestinal microbiota

Background

Inflammatory bowel disease (IBD) greatly affects human quality of life. Mannose has been reported to be used to treat IBD, but the mechanism is currently unknown.

Methods

C57/BL mice were used as research subjects, and the mouse acute colitis model was induced using dextran sulfate sodium salt (DSS). After oral administration of mannose, the body weights and disease activity index (DAI) scores of the mice were observed. The colon lengths, histopathological sections, fecal content microbial sequencing, colon epithelial inflammatory genes, and tight junction protein Occludin-1 expression levels were measured. We further used the feces of mice that had been orally administered mannose to perform fecal bacterial transplantation on the mice with DSS-induced colitis and detected the colitis-related indicators.

Results

Oral administration of mannose increased body weights and colon lengths and reduced DAI scores in mice with DSS-induced colitis. In addition, it reduced the expression of colon inflammatory genes and the levels of serum inflammatory factors (TNF-α, IL-6, and IL-1β), further enhancing the expression level of the colonic Occludin-1 protein and alleviating the toxic response of DSS to the intestinal epithelium of the mice. In addition, gut microbial sequencing revealed that mannose increased the abundance and diversity of intestinal flora. Additionally, after using the feces of the mannose-treated mice to perform fecal bacterial transplantation on the mice with DSS-induced colitis, they showed the same phenotype as the mannose-treated mice, and both of them alleviated the intestinal toxic reaction induced by the DSS. It also reduced the expression of intestinal inflammatory genes (TNF-α, IL-6, and IL-1β) and enhanced the expression level of the colonic Occludin-1 protein.

Conclusion

Mannose can treat DSS-induced colitis in mice, possibly by regulating intestinal microorganisms to enhance the intestinal immune barrier function and reduce the intestinal inflammatory response.