Lactobacillus paracasei JY062 and its exopolysaccharide enhance the intestinal barrier through macrophage polarization and Th17/Treg cell balance

Ulcerative colitis (UC) is an immune-mediated intestinal disease without a comprehensive cure, and the alleviation of UC has become an urgent problem. The results showed that JY062 with its EPS group (JEC) alleviated the intestinal barrier damage caused by LPS. After JEC intervention on Caco-2 cells, resulted in upregulation of ZO-1, Claudin-1, Occludin and MUC2 transcript levels and decreased mRNA expression of Claudin-2 (p < 0.05). JEC effectively attenuated the inflammatory response in UC mice and restoration of immunoglobulin levels (IgG, IgM and IgA), which resulted in shortening and swelling of the colon, disappearance of goblet cells, infiltration of inflammatory cells and mucosal damage were alleviated in mice. Similarly, changes in the expression of MUC2 and tight junction proteins after JEC intervention also occurred in UC mice. Administration of JEC significantly inhibited the differentiation of pro-inflammatory Th17 cells in the thymus and peripheral blood, promoted the differentiation of CD4+ T cells to Treg cells, and effectively regulated DSS-induced macrophage imbalance, which was manifested by the polarization of pro-inflammatory M1 macrophages to anti-inflammatory M2 macrophages. This study clearly demonstrates that JEC could significantly prevent intestinal barrier on DSS-induced experimental colitis and could be applied as a potential symbiotic strategy to assist in the alleviation of UC.

Multi-omics analysis reveals that agaro-oligosaccharides with different degrees of polymerization alleviate colitis in mice by regulating intestinal flora and arginine synthesis

Inflammatory bowel disease (IBD) is a common chronic disease with a complex etiology, characterized by body weight loss, intestinal barrier damage, and an imbalance of intestinal flora, posing a significant threat to people's health. In this work, we studied whether safer natural active agaro-oligosaccharides (AOSs) benefit mice with IBD and elucidated their underlying mechanisms. The findings indicated that oral administration of agarobiose (A2), agarotriose (A3), and agarotetraose (A4) contributed to alleviating body weight loss and colon shortening, as well as enhancing IL-10 levels while reducing IL-6, IL-1β, and TNF-α. AOSs improved colon disruption, reduced the number of goblet cells caused by DSS, and enhanced the expression of Muc2, ZO-1, and occludin-1 to repair the intestinal barrier. It is noteworthy that A3 demonstrated superior outcomes in the evaluated AOSs relative to A2 and A4. This was evidenced by an increase in Bacteroidota and reduced Firmicutes at the phylum level, which corrected DSS-induced intestinal dysbiosis and significantly restored disrupted metabolic pathways, including amino acid and lipid metabolism. The differential metabolites between the AOS treatment groups and the model group were mainly enriched in arginine synthesis with co-regulated critical substances N-acetyl-L-citrulline and N2-acetylornithine, which alleviated colitis. This evidence offers a fresh perspective on the potential application of AOSs as functional foods to improve intestinal inflammation and metabolism.

The Gut Microbiome Advances Precision Medicine and Diagnostics for Inflammatory Bowel Diseases

The gut microbiome emerges as an integral component of precision medicine because of its signature variability among individuals and its plasticity, which enables personalized therapeutic interventions, especially when integrated with other multiomics data. This promise is further fueled by advances in next-generation sequencing and metabolomics, which allow in-depth high-precision profiling of microbiome communities, their genetic contents, and secreted chemistry. This knowledge has advanced our understanding of our microbial partners, their interaction with cellular targets, and their implication in human conditions such as inflammatory bowel disease (IBD). This explosion of microbiome data inspired the development of next-generation therapeutics for treating IBD that depend on manipulating the gut microbiome by diet modulation or using live products as therapeutics. The current landscape of artificial microbiome therapeutics is not limited to probiotics and fecal transplants but has expanded to include community consortia, engineered probiotics, and defined metabolites, bypassing several limitations that hindered rapid progress in this field such as safety and regulatory issues. More integrated research will reveal new therapeutic targets such as enzymes or receptors mediating interactions between microbiota-secreted molecules that drive or modulate diseases. With the shift toward precision medicine and the enhanced integration of host genetics and polymorphism in treatment regimes, the following key questions emerge: How can we effectively implement microbiomics to further personalize the treatment of diseases like IBD, leveraging proven and validated microbiome links? Can we modulate the microbiome to manage IBD by altering the host immune response? In this review, we discuss recent advances in understanding the mechanism underpinning the role of gut microbes in driving or preventing IBD. We highlight developed targeted approaches to reverse dysbiosis through precision editing of the microbiome. We analyze limitations and opportunities while defining the specific clinical niche for this innovative therapeutic modality for the treatment, prevention, and diagnosis of IBD and its potential implication in precision medicine.

The chemical composition, protective effect of Rheum officinale leaf juice and its mechanism against dextran sulfate sodium-induced ulcerative colitis

BACKGROUND

Rhubarb is widely distributed and cultivated worldwide, and its leaves presented antioxidant activity and could be used as food additive. However, the chemical ingredients, and protective effect of Rheum officinale leaf juice (JROL) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) are still unclear.

PURPOSE

This paper sought to the characterization and functional properties of JROL, and explore the underlying mechanism on UC mice.

METHODS

UPLC-ESI-Q-TOF/MS and other analytical instruments were employed to determine the chemical ingredients of JROL. After inducing UC model using 3% DSS, multiple biological methods were used to evaluate its protective effect and the potential mechanism.

RESULTS

JROL is rich in proximate compositions and minerals and has high nutritional value, and contains reducing sugars, polysaccharides and pectin. Fifteen compounds were identified using UPLC-ESI-Q-TOF/MS. Among them, rutin has the highest content (2.22 %) in UPLC analysis. JROL presented protective effect on DSS-induced UC, and alleviated morphological alterations and ultra-structural feature of tissue, and the polysaccharides and flavonoids may contribute to its protective effect. JROL inhibited NF-κB/NLRP3 signaling pathway to alleviate inflammatory response, oxidative stress and intestinal injury by decreasing the expression of p-p65, p-IκBα, NLRP3, ASC, etc.. Moreover, it up-regulated the expression of tight junction proteins, and re-balanced the disturbance of gut microbiota to regulate the inflammatory response. Finally, a correlation among the inflammatory response, NF-κB/NLRP3 pathway and gut microbiota was established. Moreover, JROL presented the safety in the acute toxicity test.

CONCLUSION

JROL could be used as a potential new source for treating UC.

Dietary supplementation with non-digestible isomaltooligosaccharide and Lactiplantibacillus plantarum ZDY2013 ameliorates DSS-induced colitis via modulating intestinal barrier integrity and the gut microbiota

Non-digestible oligosaccharides have attracted attention due to their critical role in maintaining the balance of a host's gut microbiota. Lactiplantibacillus plantarum ZDY2013 was isolated from traditional fermented acid beans, which could metabolize many complex carbohydrates and had intestinal immunomodulatory effects. In our study, the ameliorative effect of a combination of non-digestible isomaltooligosaccharide (IMO) and L. plantarum ZDY2013 was investigated in dextran sulfate sodium (DSS)-induced colitis mice. The results showed that IMO could specifically promote L. plantarum ZDY2013 intestinal colonization after five days of gavage and ameliorate the symptoms of colitis (survival rate, DAI score, colon length, etc.) as well as colon tissue integrity. IMO combined with L. plantarum ZDY2013 increased the levels of intestinal tight junction proteins (ZO-1 and claudin) and mucin (MUC-2), followed by alleviation of inflammatory responses (decreased the expression of IL-1β, TNF-α, and IL-6 and increased the expression of IL-10 and IL-22) and the level of oxidative stress (decreased the level of COX-2 and iNOS and increased the expression of T-AOC and SOD). Furthermore, the combination increased the diversity of the gut microbiota and modulated the microbial structural component (decreased the abundance of Escherichia and Helicobacter and increased the abundance of Lactobacillus and SCFA-producing related species). Taken together, our results suggested that the consumption of IMO and L. plantarum ZDY2013 could improve the symptoms of colitis in mice by improving the intestinal barrier along with regulating the composition and metabolites of the gut microbiota.

Sunset Yellow dye effects on gut microbiota, intestinal integrity, and the induction of inflammasomopathy with pyroptotic signaling in male Wistar rats

Although concern persists regarding possible adverse effects of consumption of synthetic azo food dyes, the mechanisms of any such effects remain unclear. We have tested the hypothesis that chronic consumption of the food dye Sunset Yellow (SY) perturbs the composition of the gut microbiota and alters gut integrity. Male rats were administered SY orally for 12 weeks. Analysis of fecal samples before and after dye administration demonstrated SY-induced microbiome dysbiosis. SY treatment reduced the abundance of beneficial taxa such as Treponema 2, Anaerobiospirillum, Helicobacter, Rikenellaceae RC9 gut group, and Prevotellaceae UCG-003, while increasing the abundance of the potentially pathogenic microorganisms Prevotella 2 and Oribacterium. Dysbiosis disrupted gut integrity, altering the jejunal adherens junction complex E-cadherin/β-catenin and decreasing Trefoil Factor (TFF)-3. SY administration elevated LPS serum levels, activated the inflammatory inflammasome cascade TLR4/NLRP3/ASC/cleaved-activated caspase-1 to mature IL-1β and IL-18, and activated caspase-11 and gasdermin-N, indicating pyroptosis and increased intestinal permeability. The possibility that consumption of SY by humans could have effects similar to those that we have observed in rats should be examined.

Protective effect of synbiotic combination of Lactobacillus plantarum SC-5 and olive oil extract tyrosol in a murine model of ulcerative colitis

BACKGROUND

Ulcerative colitisis (UC) classified as a form of inflammatory bowel diseases (IBD) characterized by chronic, nonspecific, and recurrent symptoms with a poor prognosis. Common clinical manifestations of UC include diarrhea, fecal bleeding, and abdominal pain. Even though anti-inflammatory drugs can help alleviate symptoms of IBD, their long-term use is limited due to potential side effects. Therefore, alternative approaches for the treatment and prevention of inflammation in UC are crucial.

METHODS

This study investigated the synergistic mechanism of Lactobacillus plantarum SC-5 (SC-5) and tyrosol (TY) combination (TS) in murine colitis, specifically exploring their regulatory activity on the dextran sulfate sodium (DSS)-induced inflammatory pathways (NF-κB and MAPK) and key molecular targets (tight junction protein). The effectiveness of 1 week of treatment with SC-5, TY, or TS was evaluated in a DSS-induced colitis mice model by assessing colitis morbidity and colonic mucosal injury (n = 9). To validate these findings, fecal microbiota transplantation (FMT) was performed by inoculating DSS-treated mice with the microbiota of TS-administered mice (n = 9).

RESULTS

The results demonstrated that all three treatments effectively reduced colitis morbidity and protected against DSS-induced UC. The combination treatment, TS, exhibited inhibitory effects on the DSS-induced activation of mitogen-activated protein kinase (MAPK) and negatively regulated NF-κB. Furthermore, TS maintained the integrity of the tight junction (TJ) structure by regulating the expression of zona-occludin-1 (ZO-1), Occludin, and Claudin-3 (p < 0.05). Analysis of the intestinal microbiota revealed significant differences, including a decrease in Proteus and an increase in Lactobacillus, Bifidobacterium, and Akkermansia, which supported the protective effect of TS (p < 0.05). An increase in the number of Aspergillus bacteria can cause inflammation in the intestines and lead to the formation of ulcers. Bifidobacterium and Lactobacillus can regulate the micro-ecological balance of the intestinal tract, replenish normal physiological bacteria and inhibit harmful intestinal bacteria, which can alleviate the symptoms of UC. The relative abundance of Akkermansia has been shown to be negatively associated with IBD. The FMT group exhibited alleviated colitis, excellent anti-inflammatory effects, improved colonic barrier integrity, and enrichment of bacteria such as Akkermansia (p < 0.05). These results further supported the gut microbiota-dependent mechanism of TS in ameliorating colonic inflammation.

CONCLUSION

In conclusion, the TS demonstrated a remission of colitis and amelioration of colonic inflammation in a gut microbiota-dependent manner. The findings suggest that TS could be a potential natural medicine for the protection of UC health. The above results suggest that TS can be used as a potential therapeutic agent for the clinical regulation of UC.

High Expression Level of TRIP6 is Correlated with Poor Prognosis in Colorectal Cancer and Promotes Tumor Cell Proliferation and Migration

Globally, colorectal cancer (CRC) is one of the leading causes of health problems. More reliable molecular biomarkers for early diagnosis in CRC patients are needed. A crucial role for thyroid hormone receptor interacting protein 6 (TRIP6) is played in tumorigenesis and tumor growth. Our study aims to determine the diagnostic and prognostic roles of TRIP6 at CRC. TRIP6 gene expression levels were analyzed in this study from public databases. The relationship between TRIP6 expression and clinicopathological characteristics was explored by logistic regression analysis. Based on Kaplan-Meier (K-M) survival curves and receiver operating characteristic curves (ROC) analysis, the prognostic and diagnostic values of TRIP6 were determined. Protein-protein interaction (PPI) networks analysis were performed using the STRING database. A Spearman's correlation analysis applied for examining the correlation between TRIP6 expression, immune cell infiltration, and immune checkpoint genes. Moreover, colony formation assay and transwell assay were used to investigate the functions of TRIP6. TRIP6 was highly expressed in CRC cancer tissues and cells. K-M survival analysis indicated that a high expression of TRIP6 was associated with poor prognosis. TRIP6 expression was obviously associated with immune cell infiltration and immune checkpoint gene expression. For validation, the results of collected clinical CRC samples show that TRIP6 levels in CRC tumor tissue were higher than those of paired adjacent colorectal tissues. Additionally, in vitro experiments suggested that TRIP6 knockdown suppressed proliferation and migration in CRC cell line RKO. TRIP6 overexpression promoted the proliferation and migration of normal colon cell line NCM460. High TRIP6 expression is associated with poor prognosis in colorectal cancer and promotes tumor cell proliferation and migration which may be a potential diagnostic and prognostic biomarker and a promising therapeutic target for CRC, providing new insights into its role in CRC.

Polyphenol- and Glucuronoxylan-Rich Fiber Extract from Birch (Betula sp.) Wood Regulates Colonic Barrier Function and Cell Proliferation in Healthy Rats

Birch wood-derived fiber extracts containing glucuronoxylans (GX) and polyphenols show potential for various food technological applications. This study investigated the effect of two extracts, GXpoly and pureGX, differing in lignin content on colonic barrier function. Healthy rats were fed diets containing 10% GXpoly, pureGX, or cellulose for 4 weeks. Colon crypt depth was lower in the GX groups than in the control group, but in the proximal colon, the result was significant only in GXpoly. An artificial intelligence approach was established to measure the mucus content and goblet cells. In the distal colon, their amounts were higher in the control group than in the GX groups. All diets had a similar effect on the expression of the tight junction proteins occludin, claudin-1, and claudin-7. GXpoly enhanced the fecal IgA production. Our results suggest that GX-rich extracts could support the colonic barrier and work as functional food ingredients in the future.

Comparative efficacy and tolerability of probiotic, prebiotic, and synbiotic formulations for adult patients with mild-moderate ulcerative colitis in an adjunctive therapy: A network meta-analysis

BACKGROUND & AIMS

Probiotics, prebiotics, and synbiotics (PPS) have been widely used as adjuvant treatments in patients with ulcerative colitis (UC) in recent years. However, the most effective formulations of PPS have yet to be identified. We thus aimed to compare the efficacy and tolerability of different PPS formulations for mild-moderate UC.

METHODS

We searched PubMed, Embase, Web of Science, and Cochrane CENTRAL from inception to June 24, 2023 for double-blind randomized controlled trials. We used a frequentist approach in random-effects models for network meta-analysis and the Grading of Recommendations Assessment, Development, and Evaluation approach to evaluate the certainty of evidence.

RESULTS

We analysed data from 20 trials involving 1153 patients. The combinations of specific strains of Lactobacillus and Bifidobacterium (CLB) (odds ratio (OR), 3.85; 95 % confidence interval (CI), 1.40-10.60; low certainty) and combinations of specific strains of Lactobacillus, Bifidobacterium, and Streptococcus (CLBS) (OR, 2.20; 95 % CI, 1.47-3.28; low certainty) significantly increased the clinical remission rate in intention-to-treat analysis (ITT) when compared to placebo. Similarly, compared with placebo, the two combinations significantly reduced clinical activity scores (standardized mean difference (SMD), -1.17 (95 % CI, -1.68 to -0.65), low certainty; and SMD, -1.33 (95 % CI, -1.81 to -0.86), low certainty, respectively). Hierarchical cluster analyses showed the two combinations formed clusters with high efficacy (clinical remission in ITT and clinical activity score) and tolerability (withdrawal due to worsening symptoms) within 12 weeks.

CONCLUSION

In this systematic review, we found CLB and CLBS demonstrated a clinical benefit in adjuvant treatments, with a comparable tolerability and safety profile to placebo. Further trials are needed.

TRIAL REGISTRATION NUMBER

CRD42022344905.

Evaluating the In Vitro and In Vivo Prebiotic Effects of Different Xylo-Oligosaccharides Obtained from Bamboo Shoots by Hydrothermal Pretreatment Combined with Endo-Xylanase Hydrolysis

Xylo-oligosaccharides (XOS) enriched with high fractions of X2-X3 are regarded as an effective prebiotic for regulating the intestinal microflora. In this study, the original XOS solution was obtained from bamboo shoots through hydrothermal pretreatment under optimized conditions. Subsequently, enzymatic hydrolysis with endo-xylanase was performed on the original XOS solution to enhance the abundance of the X2-X3 fractions. The results demonstrated that hydrothermal pretreatment yielded 21.24% of XOS in the hydrolysate solution, and subsequent enzymatic hydrolysis significantly increased the proportion of the X2-X3 fractions from 38.87% to 68.21%. Moreover, the XOS solutions with higher amounts of X2-X3 fractions exhibited superior performance in promoting the growth of probiotics such as Bifidobacterium adolescentis and Lactobacillus acidophilus in vitro, leading to increased production of short-chain fatty acids. In the in vivo colitis mouse model, XOS solutions with higher contents of X2-X3 fractions demonstrated enhanced efficacy against intestinal inflammation. Compared with the colitis mice (model group), the XOS solution with higher X2-X3 fractions (S1 group) could significantly increase the number of Streptomyces in the intestinal microflora, while the original XOS solution (S2 group) could significantly increase the number of Bacteroides in the intestinal microflora of colitis mice. In addition, the abundances of Alcaligenes and Pasteurella in the intestinal microflora of the S1 and S2 groups were much lower than in the model group. This effect was attributed to the ability of these XOS solutions to enhance species diversity, reversing the imbalance and disorder within the intestinal microflora. Overall, this work highlights the outstanding potential of XOS enriched with high contents of X2-X3 fractions as a regulator of the intestinal microbiota and as an anti-colitis agent.

Recent updates on correlation between reactive oxygen species and synbiotics for effective management of ulcerative colitis

Ulcerative colitis (UC) is presently considered a multifactorial pathology, which may lead to persistent inflammatory action of the gastrointestinal tract (GIT) because of an improperly managed immunological reactivity to the intestinal microbiota found in the GIT. The immune response to common commensal microbes plays an essential role in intestinal inflammation related to UC synbiotics, and it is an important element in the optimal therapy of UC. Therefore, synbiotics, i.e., a mixture of prebiotics and probiotics, may help control the diseased state. Synbiotics alleviate the inflammation of the colon by lowering the reactive oxygen species (ROS) and improving the level of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD). Prebiotic supplementation is not a common practice at the moment, despite numerous research findings proving that the benefits of both probiotics and prebiotics encourage their continued existence and positioning in the GIT, with positive effects on human health by managing the inflammatory response. However, the fact that there have been fewer studies on the treatment of UC with different probiotics coupled with selected prebiotics, i.e., synbiotics, and the outcomes of these studies have been very favorable. This evidence-based study explores the possible role of ROS, SOD, and synbiotics in managing the UC. The proposed review also focuses on the role of alteration of gut microbiota, antioxidant defense in the gastrointestinal tract, and the management of UC. Thus, the current article emphasizes oxidative stress signaling in the GI tract, oxidative stress-based pathomechanisms in UC patients, and UC therapies inhibiting oxidative stress' effects.

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.

Synergistic synbiotic containing fructooligosaccharides and Lactobacillus delbrueckii CIDCA 133 alleviates chemotherapy-induced intestinal mucositis in mice

Intestinal mucositis is a commonly reported side effect in oncology patients undergoing chemotherapy and radiotherapy. Probiotics, prebiotics, and synbiotics have been investigated as alternative therapeutic approaches against intestinal mucositis due to their well-known anti-inflammatory properties and health benefits to the host. Previous studies showed that the potential probiotic Lactobacillus delbrueckii CIDCA 133 and the prebiotic Fructooligosaccharides (FOS) alleviated the 5-Fluorouracil (5-FU) chemotherapy-induced intestinal mucosa damage. Based on these previous beneficial effects, this work evaluated the anti-inflammatory property of the synbiotic formulation containing L. delbrueckii CIDCA 133 and FOS in mice intestinal mucosa inflammation induced by 5-FU. This work showed that the synbiotic formulation was able to modulate inflammatory parameters, including reduction of cellular inflammatory infiltration, gene expression downregulation of Tlr2, Nfkb1, and Tnf, and upregulation of the immunoregulatory Il10 cytokine, thus protecting the intestinal mucosa from epithelial damage caused by the 5-FU. The synbiotic also improved the epithelial barrier function by upregulating mRNA transcript levels of the short chain fatty acid (SCFA)-associated GPR43 receptor and the occludin tight junction protein, with the subsequent reduction of paracellular intestinal permeability. The data obtained showed that this synbiotic formulation could be a promising adjuvant treatment to be explored against inflammatory damage caused by 5-FU chemotherapy.

The role of complex interactions between the intestinal flora and host in regulating intestinal homeostasis and inflammatory bowel disease

Pharmacological treatment of inflammatory bowel disease (IBD) is inefficient and difficult to discontinue appropriately, and enterobacterial interactions are expected to provide a new target for the treatment of IBD. We collected recent studies on the enterobacterial interactions among the host, enterobacteria, and their metabolite products and discuss potential therapeutic options. Intestinal flora interactions in IBD are affected in the reduced bacterial diversity, impact the immune system and are influenced by multiple factors such as host genetics and diet. Enterobacterial metabolites such as SCFAs, bile acids, and tryptophan also play important roles in enterobacterial interactions, especially in the progression of IBD. Therapeutically, a wide range of sources of probiotics and prebiotics exhibit potential therapeutic benefit in IBD through enterobacterial interactions, and some have gained wide recognition as adjuvant drugs. Different dietary patterns and foods, especially functional foods, are novel therapeutic modalities that distinguish pro-and prebiotics from traditional medications. Combined studies with food science may significantly improve the therapeutic experience of patients with IBD. In this review, we provide a brief overview of the role of enterobacteria and their metabolites in enterobacterial interactions, discuss the advantages and disadvantages of the potential therapeutic options derived from such metabolites, and postulate directions for further research.

Nondigestible Functional Oligosaccharides: Enzymatic Production and Food Applications for Intestinal Health

Nondigestible functional oligosaccharides are of particular interest in recent years because of their unique prebiotic activities, technological characteristics, and physiological effects. Among different types of strategies for the production of nondigestible functional oligosaccharides, enzymatic methods are preferred owing to the predictability and controllability of the structure and composition of the reaction products. Nondigestible functional oligosaccharides have been proved to show excellent prebiotic effects as well as other benefits to intestinal health. They have exhibited great application potential as functional food ingredients for various food products with improved quality and physicochemical characteristics. This article reviews the research progress on the enzymatic production of several typical nondigestible functional oligosaccharides in the food industry, including galacto-oligosaccharides, xylo-oligosaccharides, manno-oligosaccharides, chito-oligosaccharides, and human milk oligosaccharides. Moreover, their physicochemical properties and prebiotic activities are discussed as well as their contributions to intestinal health and applications in foods.

Preventive and synbiotic effects of the soluble dietary fiber obtained from Lentinula edodes byproducts and Lactobacillus plantarum LP90 against dextran sulfate sodium-induced colitis in mice

BACKGROUND

Soluble dietary fiber (SDF) obtained from Lentinula edodes byproducts has beneficial effects on human intestinal health. This study aimed to examine the combined preventive and ameliorative effects of a kind of synbiotic (SDF with a molecular weight of 1.58 × 10²  kDa and Lactobacillus plantarum LP90 (LP) at 1 × 10⁹  CFU kg^-1 ) on dextran sulfate sodium-induced colitis mice.

RESULTS

The results demonstrated that synbiotic treatment could alleviate weight loss, decrease the disease activity index level and cause histological amelioration. Synbiotic treatment also promoted the production of goblet cells, increased the expression of tight junction proteins, and adjusted the production of myeloperoxidase, malondialdehyde and superoxide dismutase to repair intestinal epithelial injury. Clinical symptoms were alleviated by maintaining Th17/Treg balance, increasing interleukin 10 and immunoglobulin A levels, reducing interleukin 17a and tumor necrosis factor α production, and promoting mRNA to highly express of Foxp3 and vitamin D receptors. Moreover, synbiotic treatment could upregulate butyric acid production (4.71 ± 0.46 mol g^-1 feces, P < 0.05) and diversity of intestinal microbial to maintain intestinal homeostasis.

CONCLUSION

This study suggested that the combination of LP and SDF as a synbiotic has the potential for use as a nutritional supplement to alleviate colitis. © 2022 Society of Chemical Industry.

Inflammatory bowel disease therapeutic strategies by modulation of the microbiota: how and when to introduce pre-, pro-, syn-, or postbiotics?

Inflammatory bowel diseases (IBD), a heterogeneous group of inflammatory conditions that encompass both ulcerative colitis and Crohn's disease, represent a major public health concern. The etiology of IBD is not yet fully understood and no cure is available, with current treatments only showing long-term effectiveness in a minority of patients. A need to increase our knowledge on IBD pathophysiology is growing, to define preventive measures, to improve disease outcome, and to develop new effective and lasting treatments. IBD pathogenesis is sustained by aberrant immune responses, associated with alterations of the intestinal epithelial barrier (IEB), modifications of the enteric nervous system, and changes in microbiota composition. Currently, most of the treatments target the inflammation and the immune system, but holistic approaches targeting lifestyle and diet improvements are emerging. As dysbiosis is involved in IBD pathogenesis, pre-, pro-, syn-, and postbiotics are used/tested to reduce the inflammation or strengthen the IEB. The present review will resume these works, pointing out the stage of life, the duration, and the environmental conditions that should go along with microbiota or microbiota-derived treatments.

Direct Action of Non-Digestible Oligosaccharides against a Leaky Gut

The epithelial monolayer is the primary determinant of mucosal barrier function, and tight junction (TJ) complexes seal the paracellular space between the adjacent epithelial cells and represent the main "gate-keepers" of the paracellular route. Impaired TJ functionality results in increased permeation of the "pro-inflammatory" luminal contents to the circulation that induces local and systemic inflammatory and immune responses, ultimately triggering and/or perpetuating (chronic) systemic inflammatory disorders. Increased gut leakiness is associated with intestinal and systemic disease states such as inflammatory bowel disease and neurodegenerative diseases such as Parkinson's disease. Modulation of TJ dynamics is an appealing strategy aiming at inflammatory conditions associated with compromised intestinal epithelial function. Recently there has been a growing interest in nutraceuticals, particularly in non-digestible oligosaccharides (NDOs). NDOs confer innumerable health benefits via microbiome-shaping and gut microbiota-related immune responses, including enhancement of epithelial barrier integrity. Emerging evidence supports that NDOs also exert health-beneficial effects on microbiota independently via direct interactions with intestinal epithelial and immune cells. Among these valuable features, NDOs promote barrier function by directly regulating TJs via AMPK-, PKC-, MAPK-, and TLR-associated pathways. This review provides a comprehensive overview of the epithelial barrier-protective effects of different NDOs with a special focus on their microbiota-independent modulation of TJs.

Interaction between dietary fiber and bifidobacteria in promoting intestinal health

Bifidobacteria are considered as probiotics due to their role in promoting intestinal health, including regulating intestinal flora, controlling glycolipid metabolism, anti-colitis effects. Dietary fiber is considered as prebiotic favoring gut health. It also can be used as carbon source to support the growth and colonization of probiotics like bifidobacteria. However, because of genetic diversity, different bifidobacterial species differ in their ability to utilize dietary fiber. Meanwhile, dietary fiber with different structural properties has different effects on the bifidobacteria proliferation. The interaction between dietary fiber and bifidobacteria will consequently lead to a synergistic or antagonistic function in promoting intestinal health, therefore affecting the application of combined use of dietary fiber and bifidobacteria. In this case, we summarize the biological function of bifidobacteria, and their interaction with different dietary fiber in promoting gut health, and finally provide several strategies about their combined use.

Synbiotics and Their Antioxidant Properties, Mechanisms, and Benefits on Human and Animal Health: A Narrative Review

Antioxidants are often associated with a variety of anti-aging compounds that can ensure human and animal health longevity. Foods and diet supplements from animals and plants are the common exogenous sources of antioxidants. However, microbial-based products, including probiotics and their derivatives, have been recognized for their antioxidant properties through numerous studies and clinical trials. While the number of publications on probiotic antioxidant capacities and action mechanisms is expanding, that of synbiotics combining probiotics with prebiotics is still emerging. Here, the antioxidant metabolites and properties of synbiotics, their modes of action, and their different effects on human and animal health are reviewed and discussed. Synbiotics can generate almost unlimited possibilities of antioxidant compounds, which may have superior performance compared to those of their components through additive or complementary effects, and especially by synergistic actions. Either combined with antioxidant prebiotics or not, probiotics can convert these substrates to generate antioxidant compounds with superior activities. Such synbiotic-based new routes for supplying natural antioxidants appear relevant and promising in human and animal health prevention and treatment. A better understanding of various component interactions within synbiotics is key to generating a higher quality, quantity, and bioavailability of antioxidants from these biotic sources.

Probiotics ameliorate IgA nephropathy by improving gut dysbiosis and blunting NLRP3 signaling

Background

Recently, a few studies have indicated a relationship between the gut microbiota and IgA nephropathy (IgAN). Whether the gut microbiota participates in the pathogenesis of IgAN and whether probiotics are effective in treating IgAN are still controversial. Therefore, this study aimed to identify the differences in the structure of the gut microbiota between IgAN and controls and to evaluate the efficacy and mechanism of probiotics in the treatment of IgAN.

Methods

To address this question, 35 IgAN patients and 25 healthy volunteers were enrolled, and a mouse IgAN model was also constructed. The stool microbes were analyzed by 16S rRNA high-throughput sequencing to identify the differential strains between IgAN and healthy controls. The impact of probiotics on the structure of the intestinal flora and the efficacy of the probiotics in the treatment of IgAN were evaluated.

Results

Although the microflora structure of mice and humans was not the same, both patients and mice with IgAN exhibited gut microbiota dysbiosis, with all subjects presenting an evident decrease in Bifidobacterium levels. The Bifidobacterium proportion was negatively correlated with proteinuria and hematuria levels, indicating that the decreased Bifidobacterium abundance could be related to IgAN severity. Probiotic treatment containing Bifidobacterium in IgAN mice could significantly alleviate gut dysbiosis, specifically by increasing the proportion of beneficial bacteria and reducing the abundance of potentially pathogenic bacteria. Moreover, both probiotics and their metabolites, short-chain fatty acids (SCFAs), could attenuate IgAN clinicopathological manifestations by inhibiting the NLRP3/ASC/Caspase 1 signaling pathway.

Conclusions

Supplementation with probiotics mainly containing Bifidobacterium could markedly improve gut dysbiosis in IgAN. Moreover, both probiotics and their SCFA metabolites could attenuate the clinicopathological manifestations of IgAN by inhibiting the NLRP3/ASC/Caspase 1 signaling pathway. Therefore, probiotics have potential as an adjunctive therapy for IgAN.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03585-3.

Akkermansia muciniphila and its outer membrane protein Amuc_1100 prophylactically attenuate 5-fluorouracil-induced intestinal mucositis

5-Fluorouracil (5-FU) is a chemotherapy drug used to treat tumors. Previous studies have shown that Akkermansia muciniphila (A. muciniphila) and its outer membrane protein, Amuc_1100, alleviate dextran sodium sulfate (DSS)-induced colitis in mice. We investigated the effects of both A. muciniphila and Amuc_1100 on 5-FU-induced intestinal mucosal damage in mice. C57BL/6 mice were gavaged with A. muciniphila or Amuc_1100 daily before, during, and after 5-FU injection for a total of 14 days. By evaluating diarrheal toxicity scores, body weight changes, colonic anatomy images, and histopathology of intestinal injury in these mice, we found that A. muciniphila and Amuc_1100 alleviated 5-FU-induced intestinal mucositis. Quantitative polymerase chain reaction assays of intestinal cytokine mRNA levels demonstrated that both A. muciniphila and Amuc_1100 attenuated the upregulation of intestinal Tumor Necrosis Factor-α (TNF-α) and interleukin-6 (IL-6) induced by 5-FU treatment. In addition, they both reduced 5-FU-induced the NLR family pyrin domain containing 3 (NLRP3) inflammatory vesicle activation. Furthermore, by monitoring the mRNA expression of tight junction proteins in the intestine, we found that A. muciniphila and Amuc_1100 were capable of restoring the damaged intestinal barrier. Notably, A. muciniphila and Amuc_1100 also played a role in altering the structure of the intestinal microbial community. The present study revealed the protective role of both A. muciniphila and Amuc_1100 in the intestinal mucositis caused by 5-FU, providing new insights into treatment options.

The role of functional oligosaccharides as prebiotics in ulcerative colitis

The incidence rate of ulcerative colitis (UC) has increased significantly over the past decades and it places an increasing burden on health and social systems. The current studies on UC implicate a strong correlation between host gut microbiota immunity and the pathogenesis of UC. Meanwhile, more and more functional oligosaccharides have been reported as prebiotics to alleviate UC, since many of them can be metabolized by gut microbiota to produce short-chain fatty acids (SCFAs). The present review is focused on the structure, sources and specific applications of various functional oligosaccharides related to the prevention and treatment of UC. The available evidence for the usage of functional oligosaccharides in UC treatment are summarized, including fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), chito-oligosaccharides (COS), alginate-oligosaccharides (AOS), xylooligosaccharides (XOS), stachyose and inulin.

The Effect of Probiotics on Intestinal Tight Junction Protein Expression in Animal Models: A Meta-Analysis

This study investigates the effect of probiotics supplementation on tight junction protein (TJP) expression in animal models by meta-analysis. We estimated the effect of probiotics administration in an animal inflammatory bowel disease model based on 47 collected articles from the databases, including Sciencedirect, Pubmed, Scopus, and Google Scholar. The effect size was analyzed with the standardized mean difference, and the heterogeneity of the effect sizes was assessed using Cochran’s Q test. To explain the heterogeneity, moderate analyses, such as meta-ANOVA and meta-regression, were performed using the mixed effects model. Finally, publication bias was assessed using Egger’s linear regression test. Among the evaluated items, zonula occluden (ZO)-1 showed the highest Q statistics value, and the effect sizes of all items were positive with high significance (p < 0.0001). The I2 value of all items reflected high heterogeneity (in excess of 80%). From the results of the meta-ANOVA, the factors of the heterogeneity found in the probiotics strains were investigated. Lactobacillus reuteri was identified as having the greatest effect on claudin and ZO-1 expression. The publication bias was detected by the Egger’s linear regression test, though it revealed that the occludin and ZO-1 had larger sample sizes than the claudin. In sum, this meta-analysis reveals that probiotics are effective at improving TJP expression in a gut environment of inflammatory bowel disease (IBD)-induced animal model. Our findings will interest IBD patients, as they suggest an area warranting future study.

Bifidobacterium spp. as functional foods: A review of current status, challenges, and strategies

Members of Bifidobacterium are among the first microbes to colonize the human intestine naturally, their abundance and diversity in the colon are closely related to host health. Recently, the gut microbiota has been gradually proven to be crucial mediators of various metabolic processes between the external environment and the host. Therefore, the health-promoting benefits of Bifidobacterium spp. and their applications in food have gradually been widely concerned. The main purpose of this review is to comprehensively introduce general features, colonization methods, and safety of Bifidobacterium spp. in the human gut, highlighting its health benefits and industrial applications. On this basis, the existing limitations and scope for future research are also discussed. Bifidobacteria have beneficial effects on the host's digestive system, immune system, and nervous system. However, the first prerequisite for functioning is to have enough live bacteria before consumption and successfully colonize the colon after ingestion. At present, strain breeding, optimization (e.g., selecting acid and bile resistant strains, adaptive evolution, high cell density culture), and external protection technology (e.g., microencapsulation and protectants) are the main strategies to address these challenges in food application.

A β-N-acetylhexosaminidase Amuc_2109 from Akkermansia muciniphila protects against dextran sulfate sodium-induced colitis in mice by enhancing intestinal barrier and modulating gut microbiota

Inflammatory bowel disease (IBD) is associated with the microbial composition of the gut and its metabolites. Akkermansia muciniphila is a probiotic that exerts a significant alleviative or therapeutic effect on host enteritis. This study was designed to determine the protective effect and potential mechanism underlying the secretion of β-acetylaminohexosidase (Amuc_2109) by A. muciniphila against dextran sulfate sodium (DSS)-induced colitis in mice. C57BL/6 mice were gavaged with Amuc_2109 for 21 days, and during the last seven days of treatment, they drank DSS dissolved in their drinking water to induce colitis. Our results showed that supplementation with Amuc_2109 improved DSS-induced colitis as evidenced by lowered disease activity index (DAI) scores, reduced weight loss, increased colon length, and inhibited oxidative stress. In addition, Amuc_2109 inhibited the overexpression of inflammatory cytokines (TNF-α, IL-1β, IL-6) and the NLR family pyrin domain containing 3 (NLRP3) inflammasome in DSS-induced colitis. Furthermore, supplementation with Amuc_2109 also restored the mRNA expression of tight junction proteins (ZO-1, occludin, claudin-1). Further analysis of fecal microbial 16S rRNA sequences showed that Amuc_2109 reshaped the intestinal microbiota. While the anti-inflammatory effects of Amuc_2109 were only manifested with the wild-type protein, the anti-inflammatory effects were completely lost after the mutation of its key catalytic amino acids rendered Amuc_2109 inactive. In summary, these findings demonstrate the potential of Amuc_2109, as a therapeutic agent for ulcerative colitis. We posit that it will provide additional assistance in the prevention and treatment of mucus layer-related diseases such as ulcerative colitis.

Bifidobacterium catabolism of human milk oligosaccharides overrides endogenous competitive exclusion driving colonization and protection

Understanding how exogenous microbes stably colonize the animal gut is essential to reveal mechanisms of action and tailor effective probiotic treatments. Bifidobacterium species are naturally enriched in the gastrointestinal tract of breast-fed infants. Human milk oligosaccharides (HMOs) are associated with this enrichment. However, direct mechanistic proof of the importance of HMOs in this colonization is lacking given milk contains additional factors that impact the gut microbiota. This study examined mice supplemented with the HMO 2'fucosyllactose (2'FL) together with a 2'FL-consuming strain, Bifidobacterium pseudocatenulatum MP80. 2'FL supplementation creates a niche for high levels of B.p. MP80 persistence, similar to Bifidobacterium levels seen in breast-fed infants. This synergism impacted gut microbiota composition, activated anti-inflammatory pathways and protected against chemically-induced colitis. These results demonstrate that bacterial-milk glycan interactions alone drive enrichment of beneficial Bifidobacterium and provide a model for tunable colonization thus facilitating insight into mechanisms of health promotion by bifidobacteriain neonates.

Modulatory Properties of Food and Nutraceutical Components Targeting NLRP3 Inflammasome Activation

Inflammasomes are key intracellular multimeric proteins able to initiate the cellular inflammatory signaling pathway. NLRP3 inflammasome represents one of the main protein complexes involved in the development of inflammatory events, and its activity has been largely demonstrated to be connected with inflammatory or autoinflammatory disorders, including diabetes, gouty arthritis, liver fibrosis, Alzheimer’s disease, respiratory syndromes, atherosclerosis, and cancer initiation. In recent years, it has been demonstrated how dietary intake and nutritional status represent important environmental elements that can modulate metabolic inflammation, since food matrices are an important source of several bioactive compounds. In this review, an updated status of knowledge regarding food bioactive compounds as NLRP3 inflammasome modulators is discussed. Several chemical classes, namely polyphenols, organosulfurs, terpenes, fatty acids, proteins, amino acids, saponins, sterols, polysaccharides, carotenoids, vitamins, and probiotics, have been shown to possess NLRP3 inflammasome-modulating activity through in vitro and in vivo assays, mainly demonstrating an anti-NLRP3 inflammasome activity. Plant foods are particularly rich in important bioactive compounds, each of them can have different effects on the pathway of inflammatory response, confirming the importance of the nutritional pattern (food model) as a whole rather than any single nutrient or functional compound.

Effects of Xylo-Oligosaccharide on the Gut Microbiota of Patients With Ulcerative Colitis in Clinical Remission

Gut microbiota dysbiosis is closely associated with ulcerative colitis (UC). Prebiotic therapy is a potential approach for UC management especially remission maintaining. Xylo-oligosaccharide (XOS) is an efficient prebiotic with proven health benefits and few side effects. However, the effects of XOS on the gut microbiota of patients with UC have not been investigated previously. The aim of this study was to evaluate the prebiotic effects of XOS on the fecal microbiota of patients with UC in clinical remission using an in vitro fermentation model. Five patients with UC in clinical remission and five healthy volunteers were enrolled in this study. Fresh fecal samples of UC patients were diluted and inoculated in yeast extract, casitone and fatty acid (YCFA) medium alone or with XOS. After fermentation for 48 h, samples were collected for 16S rDNA sequencing to investigate the gut microbiota composition. Differences in the gut microbiota between healthy volunteers and UC patients in clinical remission were detected using original fecal samples. Subsequently, the differences between the YCFA medium alone or with XOS samples were analyzed to illustrate the effects of XOS on the gut microbiota of UC patients. In both principal coordinate analysis (PCoA) and principal component analysis (PCA), the fecal samples of UC patients differed from those of healthy volunteers. Linear discriminant analysis effect size (LEfSe) analysis revealed that the relative abundances of g_Roseburia and g_Lachnospiraceae_ND3007_group were higher in healthy volunteers than in UC patients, while o_Lactobacillales abundance showed the opposite trend (P < 0.05). Wilcoxon rank-sum test bar plot showed that the abundances of g_Eubacterium_halli_group and g_Lachnospiraceae_ND3007_group were higher in the healthy volunteers than in the UC patients (P < 0.05). In addition, in UC patients, the Wilcoxon rank-sum test showed that XOS fermentation promoted the growth of bacterial groups including g_Roseburia, g_Bifidobacterium, and g_Lactobacillus, which is beneficial for recovery of intestinal diseases. These results suggest that XOS can relieve dysbiosis in the feces of UC patients in clinical remission and thus represent a potential prebiotic material for maintaining remission.

Protective Effect of Probiotics Isolated from Traditional Fermented Tea Leaves (Miang) from Northern Thailand and Role of Synbiotics in Ameliorating Experimental Ulcerative Colitis in Mice

This study aimed to investigate the protective effect of probiotics and synbiotics from traditional Thai fermented tea leaves (Miang) on dextran sulfate sodium (DSS)-induced colitis in mice, in comparison to sulfasalazine. C57BL/6 mice were treated with probiotics L. pentosus A14-6, CMY46 and synbiotics, L. pentosus A14-6 combined with XOS, and L. pentosus CMY46 combined with GOS for 21 days. Colitis was induced with 2% DSS administration for seven days during the last seven days of the experimental period. The positive group was treated with sulfasalazine. At the end of the experiment, clinical symptoms, pathohistological changes, intestinal barrier integrity, and inflammatory markers were analyzed. The probiotics and synbiotics from Miang ameliorated DSS-induced colitis by protecting body weight loss, decreasing disease activity index, restoring the colon length, and reducing pathohistological damages. Furthermore, treatment with probiotics and synbiotics improved intestinal barrier integrity, accompanied by lowing colonic and systemic inflammation. In addition, synbiotics CMY46 combined with GOS remarkedly elevated the expression of IL-10. These results suggested that synbiotics isolated from Miang had more effectiveness than sulfasalazine. Thereby, they could represent a novel potential natural agent against colonic inflammation.

Alleviation effects of grape seed proanthocyanidin extract on inflammation and oxidative stress in a d-galactose-induced aging mouse model by modulating the gut microbiota

Grape seed proanthocyanidin extract delayed the d-galactose-induced aging process in mice through the gut microbiota–liver axis and microbiota–brain axis.

Treatment of Inflammatory Bowel Disease: A Comprehensive Review

Inflammatory bowel disease (IBD), as a global disease, has attracted much research interest. Constant research has led to a better understanding of the disease condition and further promoted its management. We here reviewed the conventional and the novel drugs and therapies, as well as the potential ones, which have shown promise in preclinical studies and are likely to be effective future therapies. The conventional treatments aim at controlling symptoms through pharmacotherapy, including aminosalicylates, corticosteroids, immunomodulators, and biologics, with other general measures and/or surgical resection if necessary. However, a considerable fraction of patients do not respond to available treatments or lose response, which calls for new therapeutic strategies. Diverse therapeutic options are emerging, involving small molecules, apheresis therapy, improved intestinal microecology, cell therapy, and exosome therapy. In addition, patient education partly upgrades the efficacy of IBD treatment. Recent advances in the management of IBD have led to a paradigm shift in the treatment goals, from targeting symptom-free daily life to shooting for mucosal healing. In this review, the latest progress in IBD treatment is summarized to understand the advantages, pitfalls, and research prospects of different drugs and therapies and to provide a basis for the clinical decision and further research of IBD.

A Mixture of Lactobacillus fermentum HFY06 and Arabinoxylan Ameliorates Dextran Sulfate Sodium-Induced Acute Ulcerative Colitis in Mice

Objective

Colitis is one of the main gastrointestinal diseases threatening human health.

Materials and Methods

In this study, a synbiotic composed of arabinoxylan (AX) and Lactobacillus fermentum HFY06 was tested to determine its ability to relieve dextran sulfate sodium (DSS)-induced colitis.

Results

The experimental results showed that the synergistic effect of AX and L. fermentum HFY06 alleviated the weight loss of DSS-mediated colitis mice and lowered the disease activity index (DAI) score. Determination of biochemical indicators found that the synbiotic composed of AX and L. fermentum HFY06 increased the body’s antioxidant capacity and reduced inflammation. The histopathological examination results showed that the colonic crypts of the mice in the model group were disordered, goblet cells were lost, and the mucous membrane was severely damaged. However, the combination of AX and L. fermentum HFY06 can significantly reverse the histopathological changes in the colon mediated by DSS. The gene expression of colon tissue was further determined, and the results showed that the synergistic effect of AX and L. fermentum HFY06 inhibited the activation of the NF-κB signaling pathway, downregulated the mRNA expression levels of nuclear factor-κB-p65 (NF-κBp65), upregulated the mRNA expression of NF-κB inhibitor-α (IκB-α), inhibited the release of cytokines tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX-2), and exerted anti-colitis effects.

Conclusion

This study shows that the synbiotic composed of AX and L. fermentum HFY06 has the potential to prevent and treat colitis.

Probiotic Bacillus cereus Alleviates Dextran Sulfate Sodium-Induced Colitis in Mice through Improvement of the Intestinal Barrier Function, Anti-Inflammation, and Gut Microbiota Modulation

Dysbiosis leads to continuous progress of inflammatory bowel disease (IBD). However, current therapeutic approaches for IBD have limited efficacy and are associated with various side effects. This study focused on exploring the positive effect of a new Bacillus cereus (B. cereus) strain (HMPM18123) in a colitis mouse model and elucidate the underlying molecular mechanisms. The colitis symptoms were alleviated by the B. cereus administration as evidenced by decreased body weight loss, colon length shortening, disease activity index score, and histopathological score. The B. cereus mitigated intestinal epithelial barrier damage by upregulating tight junction protein expression. Moreover, B. cereus exerted anti-inflammatory effects by regulating macrophage polarization and suppressing the TLR4-NF-κB-NLRP3 inflammasome signaling pathways. B. cereus also rebalanced the damaged gut microbiota. Thus, the molecular mechanism of alleviating colitis by B. cereus treatment involved the regulation of the TLR4-NF-κB-NLRP3 inflammasome signaling pathways in intestinal mucosal barriers by modulating gut microbiota composition.

Fructooligosaccharide supplementation alleviated the pathological immune response and prevented the impairment of intestinal barrier in DSS-induced acute colitis mice

The dysbiosis of gut microbiota is closely related to the occurrence and development of inflammatory bowel disease (IBD). The manipulation of intestinal flora through prebiotics or probiotics is expected to induce and maintain the remission of IBD symptoms. 6-week-old C57BL/J mice were daily gavaged with fructooligosaccharides (FOS) or the synbiotic two weeks before the administration of dextran sulfate sodium (DSS). The supplementation of FOS or synbiotic could significantly ameliorate the body weight loss and colon histological damage in DSS-induced acute colitis mice. The altered composition of gut microbiota in acute colitis mice was reversed by FOS or Synbiotic supplementation, with a characteristic of decreased abundance of Mucispirillum. Both FOS and synbiotic mitigated DSS-induced loss of mucus protein (MUC2) and epithelium tight junction proteins (ZO-1, Occluding, Claudin1) in colon mucosa. The expression of pro-inflammatory cytokines (IL-6 and TNF-α) was decreased by FOS or synbiotic treatment, while the expression of Tbx21 and IL-10 was increased. The results suggested that the modulation of gut microbiota by FOS or synbiotic supplementation could decrease the inflammation potential of colonized commensals, which prevented the impairment of the intestinal barrier and induced a regulation of immune response in DSS-induced acute colitis mice.

The preventive effect and underlying mechanism of Rhus chinensis Mill. fruits on dextran sulphate sodium-induced ulcerative colitis in mice

The purpose of this research was to explore the preventive effect of an 80% ethanol extract of Rhus chinensis Mill. fruits on dextran sulfate sodium (DSS)-induced colitis in mice and to elucidate the underlying molecular mechanisms of this effect. The results indicated that the extract, especially when administered at a high dose, could dramatically decrease the disease activity index, maintain normal spleen conditions, and improve colonic histopathology and length in the DSS-induced mice. In addition, extract administration could significantly suppress the levels of malondialdehyde, myeloperoxidase, tumor necrosis factor-α, interleukin-1β, and interleukin-6 and enhance superoxide dismutase and glutathione levels. The extract obviously protected intestinal barrier integrity by improving Occludin, ZO-1 and Claudin-1 expression levels. Western blot and immunohistochemistry analyses further indicated that the preventive effect of the phenol-rich extract on DSS-induced colitis might be achieved through the up-regulation of the expression of several pivotal oxidative stress-associated proteins, namely Nrf2, NQO1 and HO-1, and the down-regulation of the expression of several pivotal inflammation-associated proteins, namely p-NF-κB, p-IκB, COX-2, iNOS, p-P38, p-Erk1/2, and p-JNK. Therefore, R. chinensis fruits extract possesses the capability to prevent DSS-induced ulcerative colitis in mice and could be utilized as a natural substance in the exploitation of functional foods as an adjuvant dietary therapy for preventing and/or alleviating inflammatory bowel disease.

Dietary xylo-oligosaccharide ameliorates colonic mucus microbiota penetration with restored autophagy in interleukin-10 gene-deficient mice

BACKGROUND

Inflammatory bowel disease (IBD) is, nowadays, highly prevalent and presents a global clinical challenge. The objective of this study is to assess the effects of xylo-oligosaccharide (XOS) on Il10^-/- mice, a classic animal model of IBD.

METHODS

Male wild-type (WT) mice were assigned to WT group, and Il10^-/- mice were assigned to interleukin-10 gene-deficient (IL-10-KO) group and XOS group, respectively. There were 6-8 mice aged 8 weeks in each group. Mice in the XOS group received 1.0 g/kg/day XOS by gavage for 4 weeks.

RESULTS

Compared with mice in IL-10-KO group, Il10^-/- mice with XOS intervention presented significant mild spontaneous colitis with lower disease activity index, histological scores, and bowel inflammatory cytokine levels. Dietary XOS downregulated bowel mucus bacterial penetration, which occurred as early as the onset of bowel colitis. The effect of XOS was associated with restored expression of LC3II/I and decreased expression of p62 and beclin-1 in colon.

CONCLUSIONS

Therefore, XOS decreases colonic mucus microbiota penetration with restored function of antophagy. Our findings suggest that XOS may be a potential dietary supplement or functional food for early management of IBD.

Xylo-oligosaccharide alleviates Salmonella induced inflammation by stimulating Bifidobacterium animalis and inhibiting Salmonella colonization

Xylo-oligosaccharide (XOS), which is considered as a potential prebiotic, exhibits multiple beneficial effects on modulation of gut microbiota, strength of intestinal barrier, and inhibition of intestinal inflammation. The objective of this study is to investigate whether XOS protects against Salmonella infection by modulating gut microbiota, enhancing the intestinal barrier, and resisting colonization. C57BL/6 male mice received water supplementation with 5% XOS for 14 days before Salmonella Typhimurium infection. The results showed that XOS suppressed the Salmonella-induced inflammation, but had limited effects on tight junction molecules and mRNA expression of mucus proteins, except for claudin-1 in the colon. Data of 16S rDNA sequencing indicated that XOS modulated gut microbiota composition by significantly stimulating Bifidobacterium animalis (B. animalis), and reducing Salmonella counts. Therefore, the potential protective effects of B. animalis against Salmonella challenge were investigated as well. Bifidobacterium animalis subsp lactis BB-12 (BB12), which could markedly increase in XOS, was selected to treat mice. Similarly, Salmonella-induced inflammatory reactions were alleviated by BB12 but tight junction molecules and mucin proteins in the colonic tissues were not affected. Administration of BB12 remarkably decreased the copies of Salmonella in cecal digesta post Salmonella infection. Additionally, the decrease concentrations of cecal propionate and total short-chain fatty acids (SCFAs) in Salmonella-infected mice were reversed by BB12 treatment, and propionate performed a strong inhibitory effect on Salmonella growth in vitro. Besides that, BB12 could directly restrict Salmonella proliferation in vitro. Moreover, BB12 reduced the adhesion ability of Salmonella on the Caco-2 cells model. Our results suggest that XOS could be considered as a candidate of functional food to protect against Salmonella infection by stimulating Bifidobacterium, which then resists Salmonella colonization by maintaining the intestinal SCFAs levels and suppressing adhesibility.

Influence of fruit-based beverages on efficacy of Lacticaseibacillus rhamnosus GG (Lactobacillus rhamnosus GG) against DSS-induced intestinal inflammation

Different lines of evidences from clinical, epidemiological and biochemical studies have established that optimal nutrition including probiotic and fruit phenolics can mitigate the risk and morbidity associated with some chronic diseases. The basis for this observation is the potential synergies that may exist between probiotic strains and different bioactive components of food matrices. This study was conceptualized to compare the efficiency of a probiotic strain in two different fruit matrices. Two fruits, viz., sea buckthorn (Hippophae rhamnoides) (SBT) and apples (Malus pumila) (APJ) were chosen and the anti-inflammatory effects of L. rhamnosus GG (ATCC 53103) (LR) fortified in SBT and APJ were analysed against dextran sulphate sodium (DSS) induced colitis in zebrafish (Danio rerio). The results showed that administration of probiotic (LR) fortified, malt supplemented SBT beverage (SBT + M + LR) had better restorative potential on the intestinal barrier function and mucosal damage, in comparison to LR fortified, malt supplemented APJ beverage (APJ + M + LR). SBT + M + LR demonstrated adequate anti-oxidant potential by enhancing the CAT, SOD, GPx and GSH activities, impaired due to DSS administration. The increase in the expressions of toll like receptor (TLR)-2, TLR-4 and TLR-5 induced by DSS were significantly inhibited by SBT + M + LR administration. Gene expression of pro-inflammatory markers, (NF-κB, TNF-α, IL-1β, IL-6, IL-8, CCL20, MPO and MMP9) were attenuated by SBT + M + LR treatment in intestinal tissues of DSS-treated zebrafishes. Notably, SBT + M + LR increased the expression of anti-inflammatory cytokine, IL-10. The study provides evidence that specific interactions between fruit matrix and probiotic strain can provide adjunct therapeutic strategy to manage intestinal inflammation.

Fermentation Supernatants of Pleurotus eryngii Mushroom Ameliorate Intestinal Epithelial Barrier Dysfunction in Lipopolysaccharide-Induced Caco-2 Cells via Upregulation of Tight Junctions

In recent years, modulation of gut microbiota through prebiotics has garnered interest as a potential to ameliorate intestinal barrier dysfunction. The aim of the study was to examine the in vitro effect of fermentation supernatants (FSs) from rich in β-glucan Pleurotus eryngii mushrooms on the expression levels of tight junctions (TJs) genes in Caco-2 cells stimulated by bacterial lipopolysaccharides (LPS). Mushrooms were fermented using fecal inocula in an in vitro batch culture model. Caco-2 cells were subjected to LPS and FS treatment under three different conditions: pre-incubation with FS, co- and post-incubation. Reverse transcription PCR was applied to measure the expression levels of zonulin-1, occludin and claudin-1 genes. FSs from P. eryngii mushrooms led to a significant upregulation of the TJs gene expression in pre-incubation state, indicating potential preventive action. Down-regulation of all TJs gene expression levels was observed when the cells were challenged with LPS. The FS negative control (gut microbiota of each donor with no carbohydrate source) exhibited a significant upregulation of TJs expression levels compared to the cells that were challenged with LPS, for all three conditions. Overall, our data highlighted the positive and potential protective effects of P. eryngii mushrooms in upregulation of TJs’ genes.

Hemicellulose-Derived Oligosaccharides: Emerging Prebiotics in Disease Alleviation

The gut microbiota in the human body is an important component that plays a pivotal role in the ability of the host to prevent diseases and recover from these diseases. If the human microbiome changes for any reason, it affects the overall functioning of the host. Healthy and vigorous gut microbiota require dietary fiber supplementation. Recently, oligosaccharides have been found to play a significant role in the modulation of microbiota. Several such oligosaccharides, i.e., xylooligosaccharides (XOS), mannooligosaccharides (MOS), and arabino-xylooligosaccharides (AXOS), are derived from hemicellulosic macromolecules such as xylan, mannan, and arabino-xylan, respectively. These oligosaccharides serve as substrates for the probiotic production of health-promoting substances (short-chain fatty acids, branched chain amino acids etc.), which confer a variety of health benefits, including the prevention of some dreaded diseases. Among hemicellulose-derived oligosaccharides (HDOs), XOS have been largely explored, whereas, studies on MOS and AXOS are currently underway. HDOs, upon ingestion, help reduce morbidities by lowering populations of harmful or pathogenic bacteria. The ATP-binding cassette (ABC) transporters are mainly utilized for the uptake of oligosaccharides in probiotics. Butyrate generated by the selective fermentation of oligosaccharides, along with other short-chain fatty acids, reduces gut inflammation. Overall, oligosaccharides derived from hemicelluloses show a similar potential as conventional prebiotics and can be supplemented as functional foods. This review summarizes the role of HDOs in the alleviation of autoimmune diseases (inflammatory bowel disease, Crohn's disease), diabetes, urinary tract infection, cardiovascular diseases, and antimicrobial resistance (AMR) through the modulation of the gut microbiota. The mechanism of oligosaccharide utilization and disease mitigation is also explained.

Polyphenol-Mediated Gut Microbiota Modulation: Toward Prebiotics and Further

The genome of gut microbes encodes a collection of enzymes whose metabolic functions contribute to the bioavailability and bioactivity of unabsorbed (poly)phenols. Datasets from high throughput sequencing, metabolome measurements, and other omics have expanded the understanding of the different modes of actions by which (poly)phenols modulate the microbiome conferring health benefits to the host. Progress have been made to identify direct prebiotic effects of (poly)phenols; albeit up to date, these compounds are not recognized as prebiotics sensu stricto. Interestingly, certain probiotics strains have an enzymatic repertoire, such as tannase, α-L-rhamnosidase, and phenolic acid reductase, involved in the transformation of different (poly)phenols into bioactive phenolic metabolites. In vivo studies have demonstrated that these (poly)phenol-transforming bacteria thrive when provided with phenolic substrates. However, other taxonomically distinct gut symbionts of which a phenolic-metabolizing activity has not been demonstrated are still significantly promoted by (poly)phenols. This is the case of Akkermansia muciniphila, a so-called antiobesity bacterium, which responds positively to (poly)phenols and may be partially responsible for the health benefits formerly attributed to these molecules. We surmise that (poly)phenols broad antimicrobial action free ecological niches occupied by competing bacteria, thereby allowing the bloom of beneficial gut bacteria. This review explores the capacity of (poly)phenols to promote beneficial gut bacteria through their direct and collaborative bacterial utilization and their inhibitory action on potential pathogenic species. We propose the term duplibiotic, to describe an unabsorbed substrate modulating the gut microbiota by both antimicrobial and prebiotic modes of action. (Poly)phenol duplibiotic effect could participate in blunting metabolic disturbance and gut dysbiosis, positioning these compounds as dietary strategies with therapeutic potential.

Grape seed proanthocyanidin extract ameliorates dextran sulfate sodium-induced colitis through intestinal barrier improvement, oxidative stress reduction, and inflammatory cytokines and gut microbiota modulation

It is widely believed that grape seed proanthocyanidin extract (GSPE) exerts antioxidant and anti-inflammatory effects. Dietary supplementation with GSPE has been reported to alleviate colitis signs in mice, but the mechanisms involved require further exploration. The present study investigated how the oral administration of GSPE ameliorates colitis signs and reduces colitis-associated inflammation. C57BL/6 mice were treated with GSPE for 21 days. During the final 7 days of treatment, the mice were administered dextran sulfate sodium (DSS) dissolved in drinking water to induce experimental colitis. We found that GSPE treatment improved DSS-induced colitis, which was evidenced by decreases in disease activity index (DAI) scores, pathological scores, and oxidative stress and increases in zonula occludens-1 (ZO-1), occludin, and claudin-1 mRNA levels of colon tissue. Notably, the proinflammatory cytokines TNF-α and IL-1β were significantly downregulated as a result of GSPE treatment in colon tissues. GSPE treatment also reduced NLR family pyrin domain-containing 3 (NLRP3) inflammasome mRNA levels of colon tissue. Furthermore, an analysis of 16S rRNA sequences showed that GSPE rebalanced the DSS-damaged gut microbiota, including reducing Bacteroidetes, Dubosiella, and Veillonella, increasing Verrucomicrobia and Akkermansia, and elevating the Firmicutes to Bacteroidetes ratio. In conclusion, GSPE supplementation alleviates DSS-induced colitis by modulating inflammatory cytokines and oxidation stress, maintaining the intestinal barrier, and improving the microbial community. These results indicate that GSPE might be a new dietary strategy for the treatment of ulcerative colitis.