Exopolysaccharides from Lactobacillus plantarum NCU116 Facilitate Intestinal Homeostasis by Modulating Intestinal Epithelial Regeneration and Microbiota

Wuliangye strong aroma baijiu promotes intestinal homeostasis by improving gut microbiota and regulating intestinal stem cell proliferation and differentiation

BACKGROUND

Wuliangye strong aroma baijiu (hereafter, Wuliangye baijiu) is a traditional Chinese grain liquor containing short-chain fatty acids, ethyl caproate, ethyl lactate, other trace components, and a large proportion of ethanol. The effects of Wuliangye baijiu on intestinal stem cells and intestinal epithelial development have not been elucidated. Here, the role of Wuliangye baijiu in intestinal epithelial regeneration and gut microbiota modulation was investigated by administering a Lieber-DeCarli chronic ethanol liquid diet in a mouse model to mimic long-term (8 weeks') light/moderate alcohol consumption (1.6 g kg-1 day-1) in healthy human adults.

RESULTS

Wuliangye baijiu promoted colonic crypt proliferation in mice. According to immunofluorescence and reverse transcription-quantitative polymerase chain reaction analyses, compared with the ethanol-only treatment, Wuliangye baijiu increased the number of intestinal stem cells and goblet cells and the expression of enteroendocrine cell differentiation markers in the mouse colon. Furthermore, gut microbiota analysis showed an increase in the relative abundance of microbiota related to intestinal homeostasis following Wuliangye baijiu administration. Notably, increased abundance of Bacteroidota, Faecalibaculum, Lachnospiraceae, and Blautia may play an essential role in promoting stem-cell-mediated intestinal epithelial development and maintaining intestinal homeostasis.

CONCLUSIONS

In summary, these findings suggest that Wuliangye baijiu can be used to regulate intestinal stem cell proliferation and differentiation in mice and to alter gut microbiota distributions, thereby promoting intestinal homeostasis. This research elucidates the mechanism by which Wuliangye baijiu promotes intestinal health. © 2024 Society of Chemical Industry.

An Exopolysaccharide from Genistein-Stimulated Monascus Purpureus: Structural Characterization and Protective Effects against DSS-Induced Intestinal Barrier Injury Associated with the Gut Microbiota-Modulated Short-Chain Fatty Acid-TLR4/MAPK/NF-κB Cascade Response

Inflammatory bowel disease is a major health problem that can lead to prolonged damage to the digestive system. This study investigated the effects of an exopolysaccharide from genistein-stimulated Monascus purpureus (G-EMP) in a mouse model of colitis to clarify its molecular mechanisms and identified its structures. G-EMP (Mw = 56.4 kDa) was primarily consisted of → 4)-α-D-Galp-(1 →, → 2,6)-α-D-Glcp-(1→ and →2)-β-D-Manp-(1 → , with one of the branches being α-D-Manp-(1 →. G-EMP intervention reduced the loss of body weight, degree of colonic damage and shortening, disease activity index scores, and histopathology scores, while restoring goblet cell production and oxidative homeostasis, repairing colonic functions, and regulating inflammatory cytokines. RNA sequencing and Western blot analysis indicated that G-EMP exerts anti-inflammatory properties by suppressing the TLR4/MAPK/NF-κB inflammatory signaling pathway. G-EMP modulated the gut microbiota by improving its diversities, elevating the relative abundances of beneficial bacteria, declining the Firmicutes/Bacteroidota value, and regulating the level of short-chain fatty acids (SCFAs). Correlation analysis demonstrated strong links between SCFAs, gut microbiota, and the inflammatory response, indicating the potential of G-EMP to prevent colitis.

Exopolysaccharides Produced by Bifidobacterium longum subsp. longum YS108R Ameliorates DSS-Induced Ulcerative Colitis in Mice by Improving the Gut Barrier and Regulating the Gut Microbiota

Ulcerative colitis (UC) is a major disease that has endangered human health. Our previous study demonstrated that Bifidobacterium longum subsp. longum YS108R, a ropy exopolysaccharide (EPS)-producing bacterium, could alleviate UC in mice, but it is unclear whether EPS is the key substance responsible for its action. In this study, we proposed to investigate the remitting effect of EPS from B. longum subsp. longum YS108R on UC in a DSS-induced UC mouse model. Water extraction and alcohol precipitation were applied to extract EPS from the supernatant of B. longum subsp. longum YS108R culture. Then the animal trial was performed, and the results indicated that YS108R EPS ameliorated colonic pathological damage and the intestinal barrier. YS108R EPS suppressed inflammation via NF-κB signaling pathway inhibition and attenuated oxidative stress via the Nrf2 signaling pathway activation. Remarkably, YS108R EPS regulated gut microbiota, as evidenced by an increase in short-chain fatty acid (SCFA)-producing bacteria and a decline in Gram-negative bacteria, resulting in an increase of propionate and butyrate and a reduction of lipopolysaccharide (LPS). Collectively, YS108R EPS manipulated the intestinal microbiota and its metabolites, which further improved the intestinal barrier and inhibited inflammation and oxidative stress, thereby alleviating UC.

Chitosan oligosaccharide improves intestinal homeostasis to achieve the protection for the epithelial barrier of female Drosophila melanogaster via regulating intestinal microflora

Chitosan oligosaccharide (COS) is a new type of marine functional oligosaccharide with biological activities such as regulating intestinal microflora and improving intestinal immunity. In this study, female Drosophila melanogaster was used as a model organism to evaluate the effect of COS on intestinal injury by H2O2 induction, and its mechanism was explored through the analysis of intestinal homeostasis. The results showed that 0.25% of COS could effectively prolong the lifespan of stressed female D. melanogaster by increasing its antioxidant capacity and maintaining intestinal homeostasis, which included protecting the mechanical barrier, promoting the chemical barrier, and regulating the biological barrier by affecting its autophagy and the antioxidant signaling pathway. Additionally, the protective effect of COS on the intestinal barrier and homeostasis of D. melanogaster under oxidative stress status is directly related to its regulation of the intestinal microflora, which could decrease excessive autophagy and activate the antioxidant system to promote health.

IMPORTANCE

The epithelial barrier plays an important role in the organism's health. Chitosan oligosaccharide (COS), a new potential prebiotic, exhibits excellent antioxidant capacity and anti-inflammatory effects. Our study elucidated the protective mechanisms of COS on the intestinal barrier of Drosophila melanogaster under oxidative stress, which could provide new insights into COS application in various industries, such as food, agriculture, and medicine.

Exopolysaccharide production by Lactobacillus plantarum T10 is responsible for the probiotic activity in enhancing intestinal barrier function in vitro and in vivo

Lactobacillus probiotics exert their effects in a strain-specific and metabolite-specific manner. This study aims to identify lactobacilli that can effectively enhance the intestinal barrier function both in vitro and in vivo and to investigate the underlying metabolite and molecular mechanisms involved. Nine Lactobacillus isolates were evaluated for their ability to enhance the IPEC-J2 cellular barrier function and for their anti-inflammatory and anti-apoptotic effects in IPEC-J2 cells after an enterotoxigenic Escherichia coli challenge. Of the nine isolates, L. plantarum T10 demonstrated significant advantages in enhancing the cellular barrier function and displayed anti-inflammatory and anti-apoptotic activities in vitro. The bioactivities of L. plantarum T10 were primarily attributed to the production of exopolysaccharides, which exerted their effects through the TLR-mediated p38 MAPK pathway in ETEC-challenged IPEC-J2 cells. Furthermore, the production of EPS by L. plantarum T10 led to the alleviation of dextran sulfate sodium-induced colitis by reducing intestinal damage and enhancing the intestinal barrier function in mice. The EPS is classified as a heteropolysaccharide with an average molecular weight of 23.0 kDa. It is primarily composed of mannose, glucose, and ribose. These findings have practical implications for the targeted screening of lactobacilli used in the production of probiotics and postbiotics with strain-specific features of exopolysaccharides.

Biotics: An emerging food supplement for health improvement in the era of immune modulation

The involvement of the commensal microbiota in immune function is a multifold process. Biotics, such as probiotics, prebiotics, synbiotics, and paraprobiotics, have been subjected to animal and human trials demonstrating the association between gut microbes and immunity biomarkers leading to improvement in overall health. In recent years, studies on human microbiome interaction have established the multifarious role of biotics in maintaining overall health. The consumption of biotics has been extensively reported to help in maintaining microbial diversity, enhancing gut-associated mucosal immune homeostasis, and providing protection against a wide range of lifestyle disorders. However, the establishment of biotics as an alternative therapy for a range of health conditions is yet to be ascertained. Despite the fact that scientific literature has demonstrated the correlation between biotics and immune modulation, most in vivo and in vitro reports are inconclusive on the dosage required. This review provides valuable insights into the immunomodulatory effects of biotics consumption based on evidence obtained from animal models and clinical trials. Furthermore, we highlight the optimal dosages of biotics that have been reported to deliver maximum health benefits. By identifying critical research gaps, we have suggested a roadmap for future investigations to advance our understanding of the intricate crosstalk between biotics and immune homeostasis.

Interspecific differences and mechanisms of Lactobacillus-derived anti-inflammatory exopolysaccharides

Accumulating evidence has revealed the anti-inflammatory properties of Lactobacillus-derived exopolysaccharides (EPSs). However, interspecific differences among these Lactobacillus-derived anti-inflammatory EPSs have not been investigated. Cell experiments showed that Limosilactobacillus fermentum, Lacticaseibacillus rhamnosus, and Lactiplantibacillus plantarum-derived EPSs exhibited excellent anti-inflammatory efficacy in vitro. Subsequently, we used Lactobacillus-derived EPSs to treat colitis in mice. There was no significant difference in EPS's repair of the intestinal barrier from the five Lactobacillus species. However, Ligilactobacillus salivarius-derived EPSs and L. plantarum-derived EPSs more potently reduced proinflammatory cytokines (TNF-α, IL-1β, IL-6, TNF-γ, and IL-17), increasing IL-10 concentrations in the colon. Lactobacillus-derived EPS moieties from five species regulate intestinal bacteria at the strain level. Immunofluorescence staining revealed that owing to the different infiltration and polarization effects of Lactobacillus-derived EPSs on macrophages, the in vitro and in vivo anti-inflammatory effects of Lactobacillus-derived EPSs were inconsistent. The structure-activity relationship showed that Lactobacillus-derived EPSs with high fructose content had excellent anti-inflammatory activity in vivo. The results mentioned above revealed that the anti-inflammatory activity of Lactobacillus-derived EPSs had interspecific variability, and the mechanism of anti-inflammatory action in vitro and in vivo was different.

Disruption of intestinal epithelial permeability in the Co-culture system of Caco-2/HT29-MTX cells exposed individually or simultaneously to acrylamide and ochratoxin A

Mycotoxins and thermal processing hazards are common contaminants in various foods and cause severe problems in terms of food safety and health. Combined use of acrylamide (AA) and ochratoxin A (OTA) would result in more significant intestinal toxicity than either toxin alone, but the underlying mechanisms behind this poor outcome remain unclear. Herein, we established the co-culture system of Caco-2/HT29-MTX cells for simulating a real intestinal environment that is more sensitive to AA and OTA, and showed that the combination of AA and OTA could up-regulate permeability of the intestine via increasing LY permeabilization, and decreasing TEER, then induce oxidative stress imbalance (GSH, SOD, MDA, and ROS) and inflammatory system disorder (TNF-α, IL-1β, IL-10, and IL-6), thereby leading a rapid decline in cell viability. Western blot, PAS- and AB-staining revealed that AA and OTA showed a synergistic effect on the intestine mainly through the disruption of tight junctions (TJs) and a mucus layer. Furthermore, based on correlation analysis, oxidative stress was more relevant to the mucus layer and TJs. Therefore, our findings provide a better evaluation model and a potential mechanism for further determining or preventing the combined toxicity caused by AA and OTA.

Alleviative effects of exopolysaccharides from Limosilactobacillus mucosae CCFM1273 against ulcerative colitis via modulation of gut microbiota and inhibition of Fas/Fasl and TLR4/NF-κB pathways

Ulcerative colitis (UC) has become a public health challenge as its global prevalence increases annually. The use of prebiotics in healthcare has grown in recent years. Thus, the present study was designed to explore the alleviating effects and mechanisms of exopolysaccharides (EPS) produced by Limosilactobacillus mucosae CCFM1273 on UC. The results indicated that CCFM1273 EPS mitigated the disease symptoms and colonic pathologic damage in DSS-induced colitis mice. Moreover, CCFM1273 EPS improved the intestinal barrier by restoring goblet cell numbers and MUC2 production, enhancing intercellular junctions, and inhibiting epithelial cell apoptosis. In addition, CCFM1273 EPS inhibited colonic inflammation and oxidative stress. Importantly, CCFM1273 EPS augmented short-chain fatty acid (SCFA) producers, leading to increased levels of SCFAs (especially propionic acid), which inhibited the Fas/Fasl pathway and consequently inhibited epithelial apoptosis, and diminished Gram-negative bacteria, further decreasing lipopolysaccharides (LPS), which suppressed the TLR4/NF-κB pathway and consequently suppressed colonic inflammation, eventually relieving UC in mice. This study provides theoretical support for the use of prebiotics in clinical practice for UC.

Limosilactobacillus fermentum HF06-derived paraprobiotic and postbiotic alleviate intestinal barrier damage and gut microbiota disruption in mice with ulcerative colitis

BACKGROUND

Paraprobiotics and postbiotics have shown potential in the treatment of ulcerative colitis (UC). However, their in vivo application is still in its infancy and their mechanisms of action are not well understood.

RESULTS

Here, we investigated the mitigation effects of Limosilactobacillus fermentum HF06-derived paraprobiotic (6-PA) and postbiotic (6-PS) on dextran sulfate sodium induced UC and the potential mechanisms. Results indicated that the administration of 6-PA and 6-PS resulted in the inhibition of weight loss and colon shortening in mice with UC. Furthermore, they led to a significant reduction in both fecal moisture content and the levels of proinflammatory cytokines and oxidative stress in the intestine of the mice. 6-PA and 6-PS treatment strengthened the intestinal mucosal barrier by dramatically upregulating the levels of zonula occludens-1 and occludin proteins. In addition, 6-PA and 6-PS restored intestinal dysbiosis by regulating abundances of certain bacteria, such as Bifidobacterium, Faecalibaculum, Muribaculaceae, Corynebacterium, Escherichia-Shigella and Clostridium_sensu_stricto_1, and regulated the level of short-chain fatty acids.

CONCLUSION

These findings illustrated for the first time that L. fermentum HF06-derived paraprobiotic and postbiotic enhanced the intestinal barrier function, and restored gut microbiota alterations. © 2023 Society of Chemical Industry.

Biosorption and Bioprotective Potential of Levilactobacillus brevis in Mice Challenged by Lead-Induced Oxidative Stress

Lead (Pb) poisoning is a widespread issue in both developed and developing countries that poses a significant public health challenge. Our study aimed to explore the impact of Levilactobacillus brevis strains on inflammatory and antioxidant gene expression in the liver and brain of mice exposed to oxidative stress caused by Pb. We began by evaluating Pb absorption by Levilactobacillus brevis strains (ARKA-CH-1 (A1) and ARKA-CH-6 (A6)) using the inductively coupled plasma mass spectrometry (ICP-MS) in vitro to identify the most effective strain. We then divided four groups of BALB/c mice into control and experimental groups and treated them for 30 days. The control group received a normal diet, while the experimental groups consumed lead-containing water (0.6 g/L) with or without Levilactobacillus brevis strains. Following the experiments, we collected blood samples to test liver markers, antioxidant enzymes, and immunoglobulins. We also used real-time PCR to examine the expression of superoxide dismutase (SOD) and inducible nitric oxide synthase (iNOS) genes. The results showed that the A1 strain was the most effective in absorbing Pb. The Pb exposure led to an increase in liver enzyme values and a decrease in antioxidant enzyme activity and immunoglobulin factors. However, the combination of A1 and A6 strains had a greater effect in reducing inflammatory enzymes and increasing antioxidant enzymes. Furthermore, we observed a significant increase in iNOS gene expression and a notable decrease in SOD gene expression with Pb consumption. However, the combination of A1 and A6 strains had a synergistic effect in reducing iNOS and increasing SOD gene expression. In conclusion, Levilactobacillus brevis A1 strain alone or in combination with the A6 strain could be a promising strategy to mitigate the oxidative stress symptoms in mice challenged by lead-induced toxicity.

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.

Effects of Lacticaseibacillus paracasei SNB-derived postbiotic components on intestinal barrier dysfunction and composition of gut microbiota

The bacterial surface components are considered as effector molecules and show the potential to support intestinal health, but the detailed mechanism of how the gut microbiota changes after the intervention of surface molecules is still unknown. In the present study, capsular polysaccharide (B-CPS) and surface layer protein (B-SLP) were extracted from Lacticaseibacillus paracasei S-NB. The protective effect of direct administration of B-CPS (100 μg/mL) and B-SLP (100 μg/mL) on intestinal epithelial barrier dysfunction was verified based on the LPS-induced Caco-2 cell model. Additionally, the B-CPS and B-SLP could be utilized as carbon source and nitrogen source for the growth of several Lactobacillus strains, respectively. The postbiotic potential of B-CPS and B-SLP was further evaluated by in vitro fermentation with fecal cultures. The B-CPS and a combination of B-CPS and B-SLP regulated the composition of gut microbiota by increasing the relative abundances of Bacteroides, Bifidobacterium, Phascolarctobacterium, Parabacteroides, Subdoligranulum and Collinsella and decreasing the abundance of pathogenic bacteria like Escherichia-Shigella, Blautia, Citrobacter and Fusobacterium. Meanwhile, the total short-chain fatty acid production markedly increased after fermentation with either B-CPS individually or in combination with B-SLP. These results provided an important basis for the application of B-CPS and B-SLP as postbiotics to improve human intestinal health.

Immunomodulatory functions of microorganisms in tissue regenerative healing

External pathogenic microorganisms and commensal microorganisms in the body have either harmful or beneficial impacts on the regenerative repair of tissues, and the immune system plays a crucial regulatory role in this process. This review summarises our current understanding of microorganism-immune system interactions, with a focus on how these interactions impact the renewal and repair ability of tissues, including skin, bone, gut, liver, and nerves. This review concludes with a discussion of the mechanisms by which microbes act on various types of immune cells to affect tissue regeneration, offers potential strategies for using microbial therapies to enhance the regenerative repair function of tissues, and suggest novel therapeutic approaches for regenerative medicine. STATEMENT OF SIGNIFICANCE: Microbiological communities have crucial impacts on human health and illness by participating in energy collection and storage and performing various metabolic processes. External pathogenic microorganisms and commensal microorganisms in the body have either harmful or beneficial impacts on the regenerative repair of tissues, and the immune system plays a critical regulatory role in this process. This study reviews the important correlation between microorganisms and the immune system and investigates the mechanism of various microorganism that participate in the regeneration and repair of tissues and organs by modulating immune system.

The synergistic effects of polyphenols and intestinal microbiota on osteoporosis

Osteoporosis is a common metabolic disease in middle-aged and elderly people. It is characterized by a reduction in bone mass, compromised bone microstructure, heightened bone fragility, and an increased susceptibility to fractures. The dynamic imbalance between osteoblast and osteoclast populations is a decisive factor in the occurrence of osteoporosis. With the increase in the elderly population in society, the incidence of osteoporosis, disability, and mortality have gradually increased. Polyphenols are a fascinating class of compounds that are found in both food and medicine and exhibit a variety of biological activities with significant health benefits. As a component of food, polyphenols not only provide color, flavor, and aroma but also act as potent antioxidants, protecting our cells from oxidative stress and reducing the risk of chronic disease. Moreover, these natural compounds exhibit anti-inflammatory properties, which aid in immune response regulation and potentially alleviate symptoms of diverse ailments. The gut microbiota can degrade polyphenols into more absorbable metabolites, thereby increasing their bioavailability. Polyphenols can also shape the gut microbiota and increase its abundance. Therefore, studying the synergistic effect between gut microbiota and polyphenols may help in the treatment and prevention of osteoporosis. By delving into how gut microbiota can enhance the bioavailability of polyphenols and how polyphenols can shape the gut microbiota and increase its abundance, this review offers valuable information and references for the treatment and prevention of osteoporosis.

Fecal fermentation and high-fat diet-induced obesity mouse model confirmed exopolysaccharide from Weissella cibaria PFY06 can ameliorate obesity by regulating the gut microbiota

Obesity associated with diet and intestinal dysbiosis is a worldwide public health crisis, and exopolysaccharides (EPS) produced by lactic acid bacteria (LAB) have prebiotic potential to ameliorate obesity. Therefore, the present study obtained LAB with the ability to produce high EPS, examined the structure of EPS, and explained its mechanism of alleviating obesity by in vivo and in vitro models. The results showed that Weissella cibaria PFY06 with a high EPS yield was isolated from strawberry juice, and pure polysaccharide (PFY06-EPS) was purified by Sephadex G-100. The structural characteristics of PFY06-EPS showed that the molecular weight was 8.08 × 10⁶ Da and composed of α-(1,6)-D glucosyl residues. An in vitro simulated human colon fermentation test demonstrated that PFY06-EPS increased the abundance of Prevotella and Bacteroides. Cell tests confirmed that PFY06-EPS after fecal fermentation inhibited fat accumulation by promoting the secretion of endogenous gastrointestinal hormones and insulin and inhibiting the secretion of inflammatory factors. Notably, PFY06-EPS reduced weight gain, fat accumulation, inflammatory reactions and insulin resistance in a high-fat diet-induced obesity mouse model and improved glucolipid metabolism. PFY06-EPS intervention reversed obesity-induced microflora disorders, such as reducing the Firmicutes/Bacteroides ratio and increasing butyrate-producing bacteria (Roseburia and Oscillibacter), and reduced endotoxemia to maintain intestinal barrier integrity. Therefore, in vivo and in vitro models showed that PFY06-EPS had potential as a prebiotic that may play an anti-obesity role by improving the function of the gut microbiota.

Lactobacillus fermentum Alleviates the Colorectal Inflammation Induced by Low-Dose Sub-Chronic Microcystin-LR Exposure

Microcystin-LR (MC-LR) contamination is a worldwide environmental problem that poses a grave threat to the water ecosystem and public health. Exposure to MC-LR has been associated with the development of intestinal injury, but there are no effective treatments for MC-LR-induced intestinal disease. Probiotics are "live microorganisms that are beneficial to the health of the host when administered in sufficient quantities". It has been demonstrated that probiotics can prevent or treat a variety of human diseases; however, their ability to mitigate MC-LR-induced intestinal harm has not yet been investigated. The objective of this study was to determine whether probiotics can mitigate MC-LR-induced intestinal toxicity and its underlying mechanisms. We first evaluated the pathological changes in colorectal tissues using an animal model with sub-chronic exposure to low-dose MC-LR, HE staining to assess colorectal histopathologic changes, qPCR to detect the expression levels of inflammatory factors in colorectal tissues, and WB to detect the alterations on CSF1R signaling pathway proteins in colorectal tissues. Microbial sequencing analysis and screening of fecal microorganisms differential to MC-LR treatment in mice. To investigate the role of microorganisms in MC-LR-induced colorectal injury, an in vitro model of MC-LR co-treatment with microorganisms was developed. Our findings demonstrated that MC-LR treatment induced an inflammatory response in mouse colorectal tissues, promoted the expression of inflammatory factors, activated the CSF1R signaling pathway, and significantly decreased the abundance of Lactobacillus. In a model of co-treatment with MC-LR and Lactobacillus fermentum (L. fermentum), it was discovered that L. fermentum substantially reduced the incidence of the colorectal inflammatory response induced by MC-LR and inhibited the protein expression of the CSF1R signaling pathway. This is the first study to suggest that L. fermentum inhibits the CSF1R signaling pathway to reduce the incidence of MC-LR-induced colorectal inflammation. This research may provide an excellent experimental foundation for the development of strategies for the prevention and treatment of intestinal diseases in MC-LR.

Exopolysaccharides from Genistein-Stimulated Monascus purpureus Ameliorate Cyclophosphamide-Induced Intestinal Injury via PI3K/AKT-MAPKs/NF-κB Pathways and Regulation of Gut Microbiota

Exopolysaccharides from genistein-stimulated Monascus purpureus (G-EMP) exhibited immunomodulatory potential in vitro, but whether it had immune-enhancing effects in vivo and its potential mechanism are not yet known. Here, the immunomodulatory effects of G-EMP were investigated by establishing an immunosuppressed mouse model treated with cyclophosphamide (Cy). The results suggested that G-EMP effectively alleviated the signs of weight reduction and diet reduction caused by Cy, increased fecal water content and splenic index, and decreased the oxidative stress of the liver. Simultaneously, G-EMP improved Cy-induced intestinal injury by restoring villus length, increasing the number of cupped cells, upregulating the expression of mucin and tight junction proteins, and downregulating the ratio of apoptotic proteins (Bax/Bcl-2). It also boosted the levels of mouse colonic cytokines, CD4+ and CD8+ T cells. Additionally, G-EMP markedly enhanced immunomodulation via the activation of PI3K/AKT-MAPKs/NF-κB signal pathways. Furthermore, G-EMP intervention displayed a positive association with most immunological indexes by elevating the levels of short-chain fatty acids, varying gut microbiota composition, and enhancing beneficial bacteria (Lactobacillaceae, Prevotellaceae, and S24-7). These findings demonstrated that G-EMP can strengthen immunity, repair intestinal mucosal damage, regulate gut microbiota, and be a potential source of prebiotics.

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.

Genome Sequence and Evaluation of Safety and Probiotic Potential of Lactiplantibacillus plantarum LPJZ-658

This study aims to systematically evaluate the safety of a novel L. plantarum LPJZ-658 explored on whole-genome sequence analysis, safety, and probiotic properties assessment. Whole genome sequencing results demonstrated that L. plantarum LPJZ-658 consists of 3.26 Mbp with a GC content of 44.83%. A total of 3254 putative ORFs were identified. Of note, a putative bile saline hydrolase (BSH) (identity 70.4%) was found in its genome. In addition, the secondary metabolites were analyzed, and one secondary metabolite gene cluster was predicted to consist of 51 genes, which verified its safety and probiotic properties at the genome level. Additionally, L. plantarum LPJZ-658 exhibited non-toxic and non-hemolytic activity and was susceptible to various tested antibiotics, indicating that L. plantarum LPJZ-658 was safe for consumption. Moreover, the probiotic properties tests confirm that L. plantarum LPJZ-658 also exhibits tolerance to acid and bile salts, preferably hydrophobicity and auto-aggregation, and excellent antimicrobial activity against both Gram-positive and Gram-negative gastrointestinal pathogens. In conclusion, this study confirmed the safety and probiotic properties of L. plantarum LPJZ-658, suggesting it can be used as a potential probiotic candidate for human and animal applications.

Extraction and characterization of exopolysaccharides from Lactiplantibacillus plantarum strain PRK7 and PRK 11, and evaluation of their antioxidant, emulsion, and antibiofilm activities

Exopolysaccharides (EPS) are produced by probiotic bacteria Lactiplantibacillus plantarum PRK7 and L. plantarum PRK11. The structure of EPS-7 and EPS-11 was characterized by Fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), gas chromatography-mass spectroscopy (GCMS), and thermogravimetric analysis (TGA). Further, in in vitro studies antioxidant, emulsion, and antibiofilm activity were investigated. The FTIR spectrum confirmed the presence of polysaccharides in EPS-7 and EPS-11, with absorbance at 1654.93 and 1655.33 cm^-1, respectively. H¹ NMR further confirmed the presence of glucose, galactose, xylose, and mannose. Sugar derivatives in EPS-7 and EPS-11 were further confirmed with GCMS. The SEM analysis revealed that EPS-7 had a weblike structure and EPS-11 had a smooth porous layer. The result of the TGA revealed that EPS-7 and EPS-11 had greater thermal stability at 319.1 and 300.1 °C, respectively. Furthermore, EPS-7 and EPS-11 showed a good percentage of free radical scavenging in DPPH (89.77 % and 93.1 %), ABTS (57.65 % and 58.63 %), hydroxyl radical scavenging (44.46 % and 40.308 %), and reducing power assay. The emulsion activity was confirmed with edible oils such as coconut oil, sesame oil, almond oil, castor oil, and neem oil. The highest emulsion activity for EPS-7 and EPS-11 was found be with coconut and castor oil. In addition, the antibiofilm activity against pathogens revealed that EPS possess can prevent biofilm formation. Thus, it was found that EPS-7 and EPS-11 possess good structural characteristics and their biological activity makes them ideal for applications in the food and pharmaceutical industry.

Bifidobacterium and Lactobacillus improve inflammatory bowel disease in zebrafish of different ages by regulating the intestinal mucosal barrier and microbiota

AIMS

Inflammatory bowel disease (IBD) patients are accompanied by impaired intestinal barrier integrity and gut microbiota dysbiosis. Strategies targeting the gut microbiota are potential therapies for preventing and ameliorating IBD.

MAIN METHODS

The potential roles of two probiotic stains, Bifidobacterium longum BL986 (BL986) and Lactobacillus casei LC122 (LC122), on intestinal mucosal barrier function and microbiota in IBD zebrafish of different ages were investigated.

KEY FINDINGS

BL986 and LC122 treatment promoted the development and increased the microbiota diversity in larval zebrafish. Both probiotic treatment ameliorated mortality, promoted intestinal mucus secretion, and reduced the expression of inflammatory markers, thereby improving intestinal mucosal barrier function in dextran sulfate sodium salt (DSS)-induced ulcerative colitis (UC) and 2,4,6-trinitro-benzenesulfonicacid (TNBS)-induced Crohn's disease (CD) models in zebrafish. Moreover, the composition and function of microbiota were altered in IBD zebrafish, and probiotics treatment displayed prominent microbiota features. BL986 was more potent in the DSS-induced UC model, and increased the abundance of Faecalibaculum and butyric acid levels. LC122 exerted better protection against TNBS-induced CD, and increased the abundance of Enhydrobacter and acetic acid levels. Furthermore, the effect of probiotics was stronger in larval and aged zebrafish.

CONCLUSION

The impact of probiotics on IBD might differ from the subtypes of IBD and the age of the zebrafish, suggesting the types of disease and age should be taken into full consideration during the practical usage of probiotics.

Integrated genome based evaluation of safety and probiotic characteristics of Lactiplantibacillus plantarum YW11 isolated from Tibetan kefir

The comparative genomic analysis of Lactiplantibacillus plantarum YW11 (L. plantarum YW11) isolated from Tibetan kefir involves comparison of the complete genome sequences of the isolated strain with other closely related L. plantarum strains. This type of analysis can be used to identify the genetic diversity among strains and to explore the genetic characteristics of the YW11 strain. The genome of L. plantarum YW11 was found to be composed of a circular single chromosome of 4,597,470 bp with a G + C content of 43.2%. A total of 4,278 open reading frames (ORFs) were identified in the genome and the coding density was found to be 87.8%. A comparative genomic analysis was conducted using two other L. plantarum strains, L. plantarum C11 and L. plantarum LMG21703. Genomic comparison revealed that L. plantarum YW11 shared 72.7 and 75.2% of gene content with L. plantarum C11 and L. plantarum LMG21703, respectively. Most of the genes shared between the three L. plantarum strains were involved in carbohydrate metabolism, energy production and conversion, amino acid metabolism, and transcription. In this analysis, 10 previously sequenced entire genomes of the species were compared using an in-silico technique to discover genomic divergence in genes linked with carbohydrate intake and their potential adaptations to distinct human intestinal environments. The subspecies pan-genome was open, which correlated with its extraordinary capacity to colonize several environments. Phylogenetic analysis revealed that the novel genomes were homogenously grouped among subspecies of l Lactiplantibacillus. L. plantarum was resistant to cefoxitin, erythromycin, and metronidazole, inhibited pathogens including Listeria monocytogenes, Clostridium difficile, Vibrio cholera, and others, and had excellent aerotolerance, which is useful for industrial operations. The comparative genomic analysis of L. plantarum YW11 isolated from Tibetan kefir can provide insights into the genetic characteristics of the strain, which can be used to further understand its role in the production of kefir.

Lactobacillus salivarius Promotion of Intestinal Stem Cell Activity in Hens Is Associated with Succinate-Induced Mitochondrial Energy Metabolism

Currently, the regulation of Lactobacillus on intestinal stem cells (ISCs) attracts broad attention, but their active ingredients and the underlying mechanism are worthy of further study. Previously, host intestinal commensal bacteria were verified to drive the differentiation of ISCs. In this study, the strong bacteriostatic activity of Lactobacillus salivarius and Lactobacillus agilis were illustrated, and the components (supernatant, precipitation) of L. salivarius or L. agilis were further demonstrated to decrease the differentiation of ISCs in vivo. Interestingly, antibiotics feeding decreased ISCs differentiation in vivo as well. However, the administration of L. salivarius supernatant following antibiotics feeding was shown to promote ISCs differentiation dramatically when compared with the antibiotics feeding group, indicating that some active ingredients existed in its supernatant to promote ISCs activity. Strikingly, in vitro, the treatment of L. salivarius supernatant was further confirmed to promote the intestinal organoids' size, budding, and LGR5 expression. Next, the metabolomics analysis of Lactobacilli' supernatants suggested that succinate might be a crucial metabolite to promote ISCs activity. Further, the succinate treatment in vitro (1000 μM) and in vivo (50 mM) was confirmed to enhance the expression of LGR5 and PCNA. SLC13A3 (a sodium/dicarboxylate cotransporter) was detected in the intestinal organoids and demonstrated to transport succinate into ISCs, as confirmed by the contact of FITC-succinate with ISCs nucleus. Subsequently, high mitochondrial membrane potential and reactive oxygen species levels appeared in the intestinal organoids upon succinate treatment. Collectively, the promotion of L. salivarius on ISCs activity is associated with succinate-induced mitochondrial energy metabolism. IMPORTANCE In our previous study, Lactobacillus salivarius and Lactobacillus agilis were demonstrated to regulate intestinal stem cell activity in hens, but their active ingredients and the underlying mechanism remain unclear. In this study, L. salivarius supernatant was shown to directly promote intestinal stem cell activity. Furthermore, the succinate (a critical metabolite of L. salivarius) was screened out to promote intestinal stem cell activity. Moreover, the succinate was confirmed to enter intestinal stem cells and induce high mitochondrial energy metabolism, finally promoting intestinal stem cell activity. These findings will advance uncovering the mechanism by which Lactobacillus regulate intestinal stem cell activity in chickens.

Lactobacillus salivarius Promotion of Intestinal Stem Cell Activity in Hens Is Associated with Succinate-Induced Mitochondrial Energy Metabolism

Currently, the regulation of Lactobacillus on intestinal stem cells (ISCs) attracts broad attention, but their active ingredients and the underlying mechanism are worthy of further study. Previously, host intestinal commensal bacteria were verified to drive the differentiation of ISCs. In this study, the strong bacteriostatic activity of Lactobacillus salivarius and Lactobacillus agilis were illustrated, and the components (supernatant, precipitation) of L. salivarius or L. agilis were further demonstrated to decrease the differentiation of ISCs in vivo. Interestingly, antibiotics feeding decreased ISCs differentiation in vivo as well. However, the administration of L. salivarius supernatant following antibiotics feeding was shown to promote ISCs differentiation dramatically when compared with the antibiotics feeding group, indicating that some active ingredients existed in its supernatant to promote ISCs activity. Strikingly, in vitro, the treatment of L. salivarius supernatant was further confirmed to promote the intestinal organoids' size, budding, and LGR5 expression. Next, the metabolomics analysis of Lactobacilli' supernatants suggested that succinate might be a crucial metabolite to promote ISCs activity. Further, the succinate treatment in vitro (1000 μM) and in vivo (50 mM) was confirmed to enhance the expression of LGR5 and PCNA. SLC13A3 (a sodium/dicarboxylate cotransporter) was detected in the intestinal organoids and demonstrated to transport succinate into ISCs, as confirmed by the contact of FITC-succinate with ISCs nucleus. Subsequently, high mitochondrial membrane potential and reactive oxygen species levels appeared in the intestinal organoids upon succinate treatment. Collectively, the promotion of L. salivarius on ISCs activity is associated with succinate-induced mitochondrial energy metabolism. IMPORTANCE In our previous study, Lactobacillus salivarius and Lactobacillus agilis were demonstrated to regulate intestinal stem cell activity in hens, but their active ingredients and the underlying mechanism remain unclear. In this study, L. salivarius supernatant was shown to directly promote intestinal stem cell activity. Furthermore, the succinate (a critical metabolite of L. salivarius) was screened out to promote intestinal stem cell activity. Moreover, the succinate was confirmed to enter intestinal stem cells and induce high mitochondrial energy metabolism, finally promoting intestinal stem cell activity. These findings will advance uncovering the mechanism by which Lactobacillus regulate intestinal stem cell activity in chickens.

Exopolysaccharide from Lactobacillus rhamnosus ZFM231 alleviates DSS-induced colitis in mice by regulating gut microbiota

BACKGROUND

The exopolysaccharides (EPS) produced by Lactobacillus and other probiotics are associated with many benefits, such as immune regulation, antioxidant properties, antitumor effect, and regulation of intestinal microbe homeostasis. In the present study, the modulatory effect of EPS produced by Lactobacillus rhamnosus ZFM231 on the intestinal flora of mice with inflammatory bowel disease induced by dextran sulfate solution was investigated.

RESULTS

Results indicated that weight loss, colonic length, the disease activity index score and colonic tissue damage in mice were significantly improved by EPS treatment. Compared with the model group, in the EPS-treated group, the diversity of and the composition of gut microbiota at both phylum and genus levels were found to recover to the levels of normal group, indicating the effective modulation on gut microbiota by EPS; short-chain fatty acids, including acetic acid, propionic acid and butyric acid produced by intestinal microbial metabolism, increased significantly; the level of anti-inflammatory factor transforning growth factor-β significantly increased and the level of pro-inflammatory factor tumor necrosis factor-α significantly decreased in the colonic cells of EPS-treated mice.

CONCLUSION

It is clear that EPS produced by L. rhamnosus ZFM231 could find application in functional foods with the property of anti-ulcerative colitis. The experimental results provide new insights into the probiotic effect of EPS. © 2022 Society of Chemical Industry.

Bacterial polysaccharides-A big source for prebiotics and therapeutics

Bacterial polysaccharides are unique due to their higher purity, hydrophilic nature, and a finer three-dimensional fibrous structure. Primarily, these polymers provide protection, support, and energy to the microorganism, however, more recently several auxiliary properties of these biopolymers have been unmasked. Microbial polysaccharides have shown therapeutic abilities against various illnesses, augmented the healing abilities of the herbal and Western medicines, improved overall health of the host, and have exerted positive impact on the growth of gut dwelling beneficial bacteria. Specifically, the review is discussing the mechanism through which bacterial polysaccharides exert anti-inflammatory, antioxidant, anti-cancer, and anti-microbial properties. In addition, they are holding promising application in the 3D printing. The review is also discussing a perspective about the metagenome-based screening of polysaccharides, their integration with other cutting-edge tools, and synthetic microbiome base intervention of polysaccharides as a strategy for prebiotic intervention. This review has collected interesting information about the bacterial polysaccharides from Google Scholar, PubMed, Scopus, and Web of Science databases. Up to our knowledge, this is the first of its kind review article that is summarizing therapeutic, prebiotics, and commercial application of bacterial polysaccharides.

Intestinal Engineered Probiotics as Living Therapeutics: Chassis Selection, Colonization Enhancement, Gene Circuit Design, and Biocontainment

Intestinal probiotics are often used for the in situ treatment of diseases, such as metabolic disorders, tumors, and chronic inflammatory infections. Recently, there has been an increased emphasis on intelligent, customized treatments with a focus on long-term efficacy; however, traditional probiotic therapy has not kept up with this trend. The use of synthetic biology to construct gut-engineered probiotics as live therapeutics is a promising avenue in the treatment of specific diseases, such as phenylketonuria and inflammatory bowel disease. These studies generally involve a series of fundamental design issues: choosing an engineered chassis, improving the colonization ability of engineered probiotics, designing functional gene circuits, and ensuring the safety of engineered probiotics. In this review, we summarize the relevant past research, the progress of current research, and discuss the key issues that restrict the widespread application of intestinal engineered probiotic living therapeutics.

Lactobacillus crispatus-derived exopolysaccharides with antibacterial activity limit Salmonella typhimurium invasion by inhibiting inflammasome-mediated pyroptosis

In this study, a novel heteropolysaccharide (EPS 7-4) with a molecular weight of 53 387 Da was isolated from Lactobacillus crispatus, and it was mainly composed of mannose (36.9%) and glucose (30.8%). EPS 7-4 showed excellent inhibitory effects on the proliferation, biofilm formation, and virulence factor gene expression of Salmonella typhimurium (S. typhimurium) by disrupting the integrity of the bacterial wall. Furthermore, EPS 7-4 can effectively restrict bacterial translocation, upregulate the abundance of Lactobacillus spp. and Bifidobacterium spp., and alleviate the S. typhimurium induced severe inflammatory response in the intestinal tract of mice. Besides, we demonstrated that EPS 7-4 can protect mice by inhibiting S. typhimurium induced pyroptosis, with the mechanism that EPS 7-4 affects ASC oligomerization during inflammasome-mediated pyroptosis. Therefore, due to its excellent anti-bacterial and anti-inflammatory abilities, EPS 7-4 is a promising health regulator owing to its excellent antibacterial and anti-inflammatory abilities.

Interactions between the gut microbiota-derived functional factors and intestinal epithelial cells - implication in the microbiota-host mutualism

Mutual interactions between the gut microbiota and the host play essential roles in maintaining human health and providing a nutrient-rich environment for the gut microbial community. Intestinal epithelial cells (IECs) provide the frontline responses to the gut microbiota for maintaining intestinal homeostasis. Emerging evidence points to commensal bacterium-derived components as functional factors for the action of commensal bacteria, including protecting intestinal integrity and mitigating susceptibility of intestinal inflammation. Furthermore, IECs have been found to communicate with the gut commensal bacteria to shape the composition and function of the microbial community. This review will discuss the current understanding of the beneficial effects of functional factors secreted by commensal bacteria on IECs, with focus on soluble proteins, metabolites, and surface layer components, and highlight the impact of IECs on the commensal microbial profile. This knowledge provides a proof-of-concept model for understanding of mechanisms underlying the microbiota-host mutualism.

Functional Annotation of Lactiplantibacillus plantarum 13-3 as a Potential Starter Probiotic Involved in the Food Safety of Fermented Products

The important role of Lactiplantibacillus plantarum strains in improving the human mucosal and systemic immunity, preventing non-steroidal anti-provocative drug-induced reduction in T-regulatory cells, and as probiotic starter cultures in food processing has motivated in-depth molecular and genomic research of these strains. The current study, building on this research concept, reveals the importance of Lactiplantibacillus plantarum 13-3 as a potential probiotic and bacteriocin-producing strain that helps in improving the condition of the human digestive system and thus enhances the immunity of the living beings via various extracellular proteins and exopolysaccharides. We have assessed the stability and quality of the L. plantarum 13-3 genome through de novo assembly and annotation through FAST-QC and RAST, respectively. The probiotic-producing components, secondary metabolites, phage prediction sites, pathogenicity and carbohydrate-producing enzymes in the genome of L. plantarum 13-3 have also been analyzed computationally. This study reveals that L. plantarum 13-3 is nonpathogenic with 218 subsystems and 32,918 qualities and five classes of sugars with several important functions. Two phage hit sites have been identified in the strain. Cyclic lactone autoinducer, terpenes, T3PKS, and RiPP-like gene clusters have also been identified in the strain evidencing its role in food processing. Combined, the non-pathogenicity and the food-processing ability of this strain have rendered this strain industrially important. The subsystem and qualities characterization provides a starting point to investigate the strain’s healthcare-related applications as well.

Novel perspective on the regulation of food allergy by probiotic: The potential of its structural components

Food allergy (FA) is a global public health issue with growing prevalence. Increasing evidence supports the strong correlation between intestinal microbiota dysbiosis and food allergies. Probiotic intervention as a microbiota-based therapy could alleviate FA effectively. In addition to improving the intestinal microbiota disturbance and affecting microbial metabolites to regulate immune system, immune responses induced by the recognition of pattern recognition receptors to probiotic components may also be one of the mechanisms of probiotics protecting against FA. In this review, it is highlighted in detail about the regulatory effects on the immune system and anti-allergic potential of probiotic components including the flagellin, pili, peptidoglycan, lipoteichoic acid, exopolysaccharides, surface (S)-layer proteins and DNA. Probiotic components could enhance the function of intestinal epithelial barrier as well as regulate the balance of cytokines and T helper (Th) 1/Th2/regulatory T cell (Treg) responses. These evidences suggest that probiotic components could be used as nutritional or therapeutic agents for maintaining immune homeostasis to prevent FA, which will contribute to providing new insights into the resolution of FA and better guidance for the development of probiotic products.

Intervention and potential mechanism of non-starch polysaccharides from natural resources on ulcerative colitis: A review

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of unknown etiology that affects the colon and rectum. It has evolved into a global burden due to the high incidence in developed countries and the highly-increased incidence in developing countries. Non-starch polysaccharides (NSPs) from natural resources, as a type of functional carbohydrates, have a significant therapeutic effect on UC because of their good anti-inflammatory and immunomodulatory activities. Based on the etiology and pathogenesis of UC, this review summarizes the intervention effects and mechanisms of NSPs in the prevention and treatment of UC. The results showed that NSPs can improve UC by protecting the intestinal mucosal barrier, regulating the immune response of the intestinal mucosa, and remodeling the intestinal flora and metabolites. These contents provide theoretical basis for the application of polysaccharides in the prevention and treatment of UC.

Structure and Anti-Inflammation Potential of Lipoteichoic Acids Isolated from Lactobacillus Strains

Lactobacillus are normal inhabitants of the gastrointestinal tract and confer a variety of health effects. Lipoteichoic acid (LTA), an amphiphilic substance located in the cell membrane, is a key molecule in probiotic–host crosstalk. Through the characterization of structural characteristics of LTA molecules derived from Lactobacillus plantarum A3, Lactobacillus reuteri DMSZ 8533, and Lactobacillus acidophilus CICC 6074, there exists some heterogeneity in LTA molecules, which perhaps contributes to the distinguishable adhesion properties of Lactobacillus strains based on fluorescence microscopy observations. In LPS-induced RAW 264.7 cells, LTAs derived from three Lactobacillus strains obviously alleviated inflammatory responses as evidenced by the altered inflammatory cytokine levels of TNF-α, IL-6, and IL-10. Western blotting demonstrated that L. reuteri LTA blocked LPS-triggered expression of the MAPK and NF-κB pathways. The findings further validated that LTA is an important effector molecule and deserves further consideration as an alternative therapeutic for ulcerative colitis treatment.

Influence of Natural Polysaccharides on Intestinal Microbiota in Inflammatory Bowel Diseases: An Overview

The incidence of inflammatory bowel disease (IBD) has increased in recent years. Considering the potential side effects of conventional drugs, safe and efficient treatment methods for IBD are required urgently. Natural polysaccharides (NPs) have attracted considerable attention as potential therapeutic agents for IBD owing to their high efficiency, low toxicity, and wide range of biological activities. Intestinal microbiota and their fermentative products, mainly short-chain fatty acids (SCFAs), are thought to mediate the effect of NPs in IBDs. This review explores the beneficial effects of NPs on IBD, with a special focus on the role of intestinal microbes. Intestinal microbiota exert alleviation effects via various mechanisms, such as increasing the intestinal immunity, anti-inflammatory activities, and intestinal barrier protection via microbiota-dependent and microbiota-independent strategies. The aim of this paper was to document evidence of NP–intestinal microbiota-associated IBD prevention, which would be helpful for guidance in the treatment and management of IBD.

Effects of Exopolysaccharides from Lactiplantibacillus plantarum JLAU103 on Intestinal Immune Response, Oxidative Stress, and Microbial Communities in Cyclophosphamide-Induced Immunosuppressed Mice

This study investigated the effects of the exopolysaccharide from Lactiplantibacillus plantarum JLAU103 (EPS103) on the intestinal immune response, oxidative stress, intestinal mucosal barrier, and microbial community in cyclophosphamide-induced immune-suppressed mice. The results showed that EPS103 promoted the secretion of cytokines and the generation of secretory immunoglobulin A and mucin-2 in the small intestine of mice, which might be related to the activation of the MAPK pathway. Additionally, EPS103 protected against oxidative stress by activating antioxidation enzymes and Nrf2/Keap1 pathways. It also improved the intestinal physical barrier functions via regulating the ratio of villous height to crypt depth and upregulating the expression of tight-junction proteins. Meanwhile, EPS103 promoted the generation of short-chain fatty acids (SCFAs) and modulated the constituents of gut microbiota. These results suggested that EPS103 may modulate the intestinal immunoresponse relying on the regulation of SCFA production and gut microbiota in immunosuppressed mice, resulting in the activation of systemic immunity.

Protective Effects of Natural Polysaccharides on Intestinal Barrier Injury: A Review

Owing to their minimal side effects and effective protection from oxidative stress, inflammation, and malignant growth, natural polysaccharides (NPs) are a potential adjuvant therapy for several diseases caused by intestinal barrier injury (IBI). More studies are accumulating on the protective effects of NPs with respect to IBI, but the underlying mechanisms remain unclear. Thus, this review aims to represent current studies that investigate the protective effects of NPs on IBI by directly maintaining intestinal epithelial barrier integrity (inhibiting oxidative stress, regulating inflammatory cytokine expression, and increasing tight junction protein expression) and indirectly regulating intestinal immunity and microbiota. Furthermore, the mechanisms underlying IBI development are briefly introduced, and the structure-activity relationships of polysaccharides with intestinal barrier protection effects are discussed. Potential developments and challenges associated with NPs exhibiting protective effects against IBI have also been highlighted to guide the application of NPs in the treatment of intestinal diseases caused by IBI.

Multi-functional Potential of Five Lactic Acid Bacteria Strains Derived from Giant Panda (Ailuropoda melanoleuca)

The multi-functional properties of lactic acid bacteria (LAB) on host health have been a popular research topic. The aim of present study was to assess the multi-functional potential of five LAB strains isolated from giant panda. In this study, we analyzed five giant panda LAB strains (Weissella confuse WJ202003 (W3), WJ202009 (W9), WJ202021 (W21), BSP201703 (X₃); Lactiplantibacillus plantarum BSGP201683 (G83)) and found that they exhibited rapid growth as well as strong acid production capacity. The five LAB strains possessed high cell surface hydrophobicity to the four tested solvents (xylene, hexadecane, chloroform, ethyl acetate; except strain W9), auto-aggregation ability, co-aggregation ability with three pathogens (Escherichia coli, Enterotoxigenic Escherichia coli, Salmonella), adhesion ability to Caco-2 cell line, and strongly biofilm formation ability, suggesting an adhesion property. As investigated for their antioxidative potential, all the strains showed good tolerance to H₂O₂, high scavenging ability against 1, 1-diphenyl-2-picrylhydrazyl (DPPH), and hydroxyl (OH^-), and reduction ability. Furthermore, the five LAB strains could produce multiple probiotic substances, including exopolysaccharide (EPS), gamma-aminobutyric acid (GABA), bile salt hydrolase (BSH), cellulase (only strain G83), and protease (except strain X₃), which was the first to report the production of EPS, GABA, BSH, cellulase, and protease in giant panda-derived LAB strain. These results demonstrated that strains W3, W9, W21, X₃, and G83 had multi-functional potential and could be utilized as potential probiotics for giant panda.

Structural characterization of exopolysaccharides from Weissella cibaria NC516.11 in distiller grains and its improvement in gluten-free dough

In this study, an exopolysaccharide (EPS) was produced by Weissella cibaria NC516.11 isolated from distiller grains of Chinese Baijiu. The structural characterization of EPS determined using fourier transform infrared spectra and nuclear magnetic resonance spectra demonstrated that W. cibaria NC516.11 had α-(1 → 6) (93.46%) d-glucose linkages with a few α-(1 → 3) (6.54%) d-glucose linked branches. The monosaccharide composition of the EPS was glucose, and its molecular weight was 2.82 × 10⁶ Da. Scanning electron microscopy showed that the microstructure of EPS had a three-dimensional structure at low magnification and a particle structure that protruded from the surface at high magnification. The addition of EPS into dough can promote the cross-linking of starch molecules and increase the water-holding capacity. Dynamic rheology indicated that the aqueous solution of EPS is a pseudoplastic fluid, and the higher the concentration of EPS, the greater the viscosity. The addition of EPS to the gluten-free dough showed G' > G", which could increase the viscoelastic properties of the dough and enhance the gluten network.

Exopolysaccharide Produced by Lactiplantibacillus plantarum-12 Alleviates Intestinal Inflammation and Colon Cancer Symptoms by Modulating the Gut Microbiome and Metabolites of C57BL/6 Mice Treated by Azoxymethane/Dextran Sulfate Sodium Salt

Exopolysaccharide produced by Lactiplantibacillus plantarum-12 (LPEPS) exhibited the anti-proliferating effect on human colon cancer cell line HT-29 in vitro. The purpose of the study was to determine the alleviating effects of LPEPS on colon cancer development of the C57BL/6 mice treated by azoxymethane/dextran sulfate sodium salt (AOM/DSS). The C57BL/6 mice treated by AOM/DSS were orally administered LPEPS daily for 85 days. The results showed that LPEPS oral administration enhanced colon tight-junction protein expression and ameliorated colon shortening and tumor burden of the AOM/DSS treated mice. Furthermore, LPEPS oral administration significantly reduced pro-inflammatory factors TNF-α, IL-8, and IL-1β levels and increased anti-inflammatory factor IL-10 level in the serum of the AOM/DSS-treated mice. LPEPS oral administration reversed the alterations of gut flora in AOM/DSS-treated mice, as evidenced by the increasing of the abundance of Bacteroidetes, Bacteroidetes/Firmicutes ratio, Muribaculaceae, Burkholderiaceae, and norank_o__Rhodospirillales and the decreasing of the abundance of Firmicutes, Desulfovibrionaceae, Erysipelotrichaceae, and Helicobacteraceae. The fecal metabolites of the AOM/DSS-treated mice were altered by LPEPS oral administration, involving lipid metabolism and amino acid metabolism. Together, these results suggested that LPEPS oral administration alleviated AOM/DSS-induced colon cancer symptoms of the C57BL/6 mice by modulating gut microbiota and metabolites, enhancing intestine barrier, inhibiting NF-κB pathway, and activating caspase cascade.

Alleviative Effects of Exopolysaccharide Produced by Lactobacillus helveticus KLDS1.8701 on Dextran Sulfate Sodium-Induced Colitis in Mice

Ulcerative colitis (UC) is a non-specific chronic inflammatory disease with lesions located in the colon and rectum. The aim of this study was to evaluate the anti-inflammatory effects of exopolysaccharide-1 (EPS-1) isolated by L. helveticus KLDS1.8701 on UC. The anti-inflammatory effects of EPS-1 were studied using dextran sulphate sodium (DSS)-induced UC model. In vivo results showed that EPS-1 administration significantly ameliorated weight loss, colon shortening, disease activity index (DAI) score, myeloperoxidase (MPO) activity, and colon tissue damage. In addition, EPS-1 administration significantly decreased the levels of pro-inflammatory cytokines and increased levels of anti-inflammatory cytokines. Meanwhile, EPS-1 administration significantly up-regulated the expression of tight junction proteins and mucin. Furthermore, EPS-1 administration modulated gut microbiota composition caused by DSS and increased the short-chain fatty acids (SCFAs) levels. Collectively, our study showed the alleviative effects of EPS- isolated by L. helveticus KLDS1.8701 on DSS-induced UC via alleviating intestinal inflammation, improving mucosal barrier function, and modulating gut microbiota composition.

Glucomannan from Aloe vera Gel Promotes Intestinal Stem Cell-Mediated Epithelial Regeneration via the Wnt/β-Catenin Pathway

Intestinal stem cells (ISCs) are essential to maintain intestinal epithelial regeneration and barrier function. Our previous work showed that glucomannan from Aloe vera gel (AGP) alleviated epithelial damage, but the mechanism was still elusive. Herein, RNA-sequencing analysis showed that proliferation and differentiation of intestinal epithelial cells as well as the canonical Wnt pathway were involved in this process. Further experiments exhibited that AGP promoted nuclear translocation of β-catenin and expression of transcription factor 7, increased the number of Lgr5⁺ ISCs, and differentiated epithelial cells in mice colon. Intriguingly, AGP reversed the inhibition of IEC-6 cells proliferation induced by an inhibitor of the canonical Wnt pathway. Hence, this study implied that AGP promoted proliferation and differentiation of colon stem cells via Wnt/β-catenin signaling, which subsequently facilitated the regeneration of epithelial cells and alleviated colitis in mice. It may provide new insights into the role of polysaccharides in regulating intestinal homeostasis and relieving intestinal injury.