Oryzanol Ameliorates DSS-Stimulated Gut Barrier Damage via Targeting the Gut Microbiota Accompanied by the TLR4/NF-κB/NLRP3 Cascade Response In Vivo

Evaluating the anti-inflammatory and antioxidant efficacy of complementary and alternative medicines (CAM) used for management of inflammatory bowel disease: a comprehensive review

Inflammatory bowel disease (IBD) is a chronic autoimmune condition whose pathogenesis has not been fully elucidated, and current treatments are not definitive and often carry several side effects. The Complementary and Alternative Medicine (CAM) offers a new approach to conventional medicine. However, their clinical application and mechanisms remain limited.Objective: The aim of this review is to evaluate the anti-inflammatory, impact on microbiota and antioxidant efficacy of currently available CAM for IBD.Methods: The literature collection was obtained from Google Scholar, MEDLINE, PubMed and Web of Science (WOS). Studies in both human and animal models, published in English language between 2018 and 2024, were selected. Sixty-seven studies were included in the current review after inclusion and exclusion screening processes.Results: Mostly, studies showed significant anti-inflammatory, gut microbiota restoring, antioxidant effects of polyphenols, polysaccharides, emodin, short-chain fatty acids (SCFA; including butyrate, propionate and acetate), and probiotics although some contrasting results were noted. Current evidence shows that polyphenols exhibit the most consistent result in alleviating IBD pathophysiology, primarily due to their significant SCFA-elevating effect.Discussion: Future studies may focus on human studies, narrowing down on individual factors which may change natural product's metabolism. Further research studies are also essential to obtain therapeutic recommendations.

A novel peptide from yak ameliorates hypoxia-induced cardiac dysfunction via targeting gut microbiota and HIF-1α pathway

Due to the high altitude and low oxygen levels, individuals residing or traveling in high-altitude regions often experience hypoxic cardiac dysfunction, which significantly affects their overall well-being and quality of life. Our previous investigations showed that peptide from yak milk residue exhibits notable antioxidant, anti-inflammatory, and anti-apoptotic properties that may have a good regulatory effect on hypoxic cardiac dysfunction. In this study, our results suggest that oral administration of yak milk peptide T3 improves the cardiac dysfunction of mice by the hypoxia-inducible factor 1α (HIF-1α) pathway, and these results may be related to the regulation of T3 on the gut microbiota of mice. Additionally, oral administration T3 enhances the permeability of the intestinal barrier and reduces intestinal inflammation. Further analysis revealed that the genera Oscillospira, Clostridium, and Staphylococcus are associated with aspartate aminotransferase, lactate dehydrogenase, and reactive oxygen species levels in heart tissues, which could ameliorate hypoxia-induced myocardial injury in mice. In vitro cell models have also confirmed that T3 intervention can activate the HIF-1α pathway and inhibit myocardial inflammation and cardiomyocyte apoptosis. These findings suggest that T3 may be a potential candidate for developing functional foods to reduce hypoxia-induced cardiac dysfunction.

Integrated metabolomics and intestinal microbiota analysis to reveal anti-post-weaning diarrhea mechanisms of Modified Yupingfeng Granule in Rex rabbits

Introduction

Post-weaning Diarrhea (PWD) is a kind of physiological stress diarrhea in Rex rabbits after weaning, which can lead to death in severe cases. Traditional Chinese medicine (TCM) has been widely used in animal due to its advantages of natural origin, diverse functions, safety, reliability, economy and environmental protection. Modified Yupingfeng Granule (MYPFG) is an improved Yupingfeng prescription based on the famous traditional Chinese prescription Yupingfeng (YPF), which is combined with other TCM and has obvious synergistic and additive activity in order to obtain an excellent natural medicine for PWD.

Methods

In this study, 120 weaned Rex rabbits were randomly allocated to 4 treatment groups, including control (CON), low dose (LD), medium dose (MD), high dose (HD). Rabbits were fed a control diet or a different MYPFG proportions of diet for 30 days. The study combined 16S rRNA analysis of intestinal microbiota and cecal contents metabolomics to explore the MYPFG effect on weaned Rex rabbits.

Results

MYPFG increased average daily gain, villus length to crypt depth ratio and decreased the feed to meat ratio, diarrhea frequency, mortality rate, depth of crypt (p < 0.05). The intestinal microbiota test found that MYPFG could change the abundances of Patescibacteria, Sphingobium, Ruminococcus, and Oxalobacter. Metabolomics analysis found that effect may be related to its regulation of Glycine, serine and threonine metabolism, Arginine and proline metabolism. Nicotinate and nicotinamide metabolism.

Discussion

MYPFG could regulate intestinal microbiota and change the metabolic pathway of some amino acids to alleviate the PWD in Rex rabbits.

L-Theanine Mitigates Acute Alcoholic Intestinal Injury by Activating the HIF-1 Signaling Pathway to Regulate the TLR4/NF-κB/HIF-1α Axis in Mice

BACKGROUND/OBJECTIVES

Acute alcohol consumption can cause intestinal dysfunction, whereas L-theanine (LTA) has shown the potential to support intestinal health. We explored L-theanine's ability to protect against acute alcohol-induced injury.

METHODS

Male C57BL/6 mice were administered LTA for 28 d and then underwent acute alcohol intestinal injury modeling for 8 days.

RESULTS

The results revealed that LTA ameliorated alcohol-induced pathological damage in the duodenum and gut permeability, improved secretory immunoglobulin A (SIgA) content, and reduced oxidative stress, inflammatory markers, and serum lipopolysaccharide (LPS) content in mice. Furthermore, LTA restored the composition of the intestinal flora, increasing the abundance of Alloprevotella, Candidatus_Saccharimonas, Muribaculum, and Prevotellaceae_UCG-001. Additionally, LTA increased beneficial metabolites, such as oxyglutaric acid and L-ascorbic acid, in the HIF-1 pathway within the enrichment pathway. Further investigation into the HIF-1 signaling pathway identified up-regulation of claudin-1, HIF-1α, occludin, and ZO-1, and down-regulation of TLR4, PHD2, p65 NF-κB, TNF-α, and IFN-γ mRNA and protein levels.

CONCLUSIONS

These results suggest that LTA may enhance the intestinal barrier by activating the HIF-1 signaling pathway to regulate the TLR4/NF-κB/HIF-1α axis, thereby reducing acute alcoholic intestinal injury.

Polysaccharides from Lycium barbarum, yam, and sunflower ameliorate colitis in a structure and intrinsic flora-dependent manner

Polysaccharides have been suggested to ameliorate metabolic diseases. However, their differential colitis-mitigating effects in mouse models with different colony structures remain poorly understood. Therefore, this study investigated the effects of polysaccharides from Lycium barbarum (LBP), sunflower (SP), and yam (YP) on colitis in C57BL/6 J (B6) mice born via vaginal delivery (VD) and in both caesarean section (CS)- and VD-born Institute of Cancer Research (ICR) mice. LBP was mainly composed of glucose (30.2 %), galactose (27.5 %), and arabinose (26.9 %). The main components of SP and YP were galacturonic acid (75.8 %) and glucose (98.1 %), respectively. Interestingly, LBP effectively alleviated body weight loss, reduced inflammatory cytokine levels, and restored intestinal barrier function in all three mouse models. Moreover, LBP decreased the abundance of norank_f__norank_o__Clostridia_UCG-014, Coriobacteriaceae_UCG-002, and norank_f_Eubacterium_coprostanoligenes_group in B6 mice, and the abundance of these genera positively correlated with pro-inflammatory cytokine levels. LBP increased the abundance of Lactobacillus, which was positively correlated with the levels of the protective factor, IL-10, in CS-born ICR mice. Collectively, our study suggests the potential application of LBP in the treatment of ulcerative colitis. We also provide an alternative method for restoring intestinal homeostasis in CS-born offspring.

Gut microbiota: a novel target for exercise-mediated regulation of NLRP3 inflammasome activation

The NOD-like receptor family pyrin domain-containing 3 (NLRP3) is a key pattern recognition receptor in the innate immune system. Its overactivation leads to the production of pro-inflammatory cytokines, such as IL-1β and IL-18, which contribute to the development and progression of various diseases. In recent years, evidence has shown that gut microbiota plays an important role in regulating the activation of NLRP3 inflammasome. Variations in the function and composition of gut microbiota can directly or indirectly influence NLRP3 inflammasome activation by influencing bacterial components and gut microbiota metabolites. Additionally, exercise has been shown to effectively reduce NLRP3 inflammasome overactivation while promoting beneficial changes in gut microbiota. This suggests that gut microbiota may play a key role in mediating the effects of exercise on NLRP3 inflammasome regulation. This review explores the impact of exercise on gut microbiota and NLRP3 inflammasome activation, and examines the mechanisms through which gut microbiota mediates the anti-inflammatory effects of exercise, providing new avenues for research.

Design, synthesis, in vitro and in vivo biological evaluation of pterostilbene derivatives for anti-inflammation therapy

Pterostilbene (PST) is a naturally derived stilbene compound in grapes, blueberries, and other fruits. It is also a natural dietary compound with a wide range of biological activities such as antioxidant, anti-inflammatory, antitumor, and so on. Structural modifications based on the chemical scaffold of the pterostilbene skeleton are of great importance for drug discovery. In this study, pterostilbene skeletons were used to design novel anti-inflammatory compounds with high activity and low toxicity. A total of 30 new were found and synthesised, and their anti-inflammatory activity and safety were screened. Among them, compound E2 was the most active (against NO: IC50 = 0.7 μM) than celecoxib. Further studies showed that compound E2 exerted anti-inflammatory activity by blocking LPS-induced NF-κB/MAPK signalling pathway activation. In vivo experiments revealed that compound E2 had a good alleviating effect on acute colitis in mice. In conclusion, compound E2 may be a promising anti-inflammatory lead compound.

The protective effect of S-adenosylmethionine on chronic adolescent stress-induced depression-like behaviors by regulating gut microbiota

The efficacy and tolerability of current antidepressants for adolescent depression are inadequate. S-adenosylmethionine (SAMe), known for its effectiveness and minimal side effects in adult depression, remains unstudied in adolescents. This study explored the potential of SAMe to address depression-like behaviors in juvenile rats induced by chronic unpredictable mild stress (CUMS), with a focus on gut microbiome interactions. Adolescent male Wistar rats were subjected to a 4-week CUMS regimen and received daily intraperitoneal injections of 300 mg/kg SAMe. Behavioral assessments included the sucrose preference test, elevated plus maze test, open field test, and Y-maze test. Histopathological changes of the hippocampus and colon were observed by Nissl staining and hematoxylin and eosin staining, respectively. Gut microbiome composition was analyzed using Accurate 16S absolute quantification sequencing. The results showed that SAMe significantly improved behavioral outcomes, reduced histopathological damages in hippocampal neurons and colon tissues, and modulated the gut microbiota of depressed rats. It favorably altered the ratio of Bacteroidetes to Firmicutes, decreased the absolute abundance of Deferribacteres, and adjusted levels of key microbial genera associated with depression-like behaviors. These results suggested that SAMe could effectively counter depression-like behaviors in CUMS-exposed adolescent rats by mitigating hippocampal neuronal and colon damage and modulating the gut microbiota. This supports SAMe as a viable and tolerable treatment option for adolescent depression, highlighting the importance of the gut-brain axis in therapeutic strategies.

Exploration of the Muribaculaceae Family in the Gut Microbiota: Diversity, Metabolism, and Function

The gut microbiota are mainly composed of Bacteroidetes and Firmicutes and are crucial for metabolism and immunity. Muribaculaceae are a family of bacteria within the order Bacteroidetes. Muribaculaceae produce short-chain fatty acids via endogenous (mucin glycans) and exogenous polysaccharides (dietary fibres). The family exhibits a cross-feeding relationship with probiotics, such as Bifidobacterium and Lactobacillus. The alleviating effects of a plant-based diet on inflammatory bowel disease, obesity, and type 2 diabetes are associated with an increased abundance of Muribaculaceae, a potential probiotic bacterial family. This study reviews the current findings related to Muribaculaceae and systematically introduces their diversity, metabolism, and function. Additionally, the mechanisms of Muribaculaceae in the alleviation of chronic diseases and the limitations in this field of research are introduced.

Tannic acid alleviates ETEC K88-induced intestinal damage through regulating the p62-keap1-Nrf2 and TLR4-NF-κB-NLRP3 pathway in IPEC-J2 cells

BACKGROUND

Tannic acid (TA), a naturally occurring polyphenol, has shown diverse potential in preventing intestinal damage in piglet diarrhea induced by Enterotoxigenic Escherichia coli (ETEC) K88. However, the protective effect of TA on ETEC k88 infection-induced post-weaning diarrhea and its potential mechanism has not been well elucidated. Therefore, an animal trial was carried out to investigate the effects of dietary supplementation with TA on the intestinal diarrhea of weaned piglets challenged with ETEC K88. In addition, porcine intestinal epithelial cells were used as an in vitro model to explore the mechanism through which TA alleviates intestinal oxidative damage and inflammation.

RESULTS

The results indicated that TA supplementation (2 and 4 g kg-1) reduced diarrhea rate, enzyme activity (diamine oxidase [DAO] and Malondialdehyde [MAD]) and serum inflammatory cytokines concentration (TNF-α and IL-1β) (P < 0.05) compared to the Infection group (IG), group in vivo. In vitro, TA treatment effectively alleviated ETEC-induced cytotoxicity, increased the expression of ZO-1, occludin and claudin-1 at both mRNA and protein levels. Moreover, TA pre-treatment increased the activity of antioxidant enzymes (such as T-SOD) and decreased serum cytokine levels (TNF-α and IL-1β). Furthermore, TA increased cellular antioxidant capacity by activating the Nrf2 signaling pathway and decreased inflammatory response by down-regulating the expression of TLR4, MyD88, NF-kB and NLRP3.

CONCLUSION

The present study showed that TA reduced the diarrhea rate of weaned piglets by restoring the intestinal mucosal mechanical barrier function, alleviating oxidative stress and inflammation. The underlying mechanism was achieved by modulating the p62-keap1-Nrf2 and TLR4-NF-κB-NLRP3 pathway. © 2024 Society of Chemical Industry.

Sishen Wan enhances intestinal barrier function via regulating endoplasmic reticulum stress to improve mice with diarrheal irritable bowel syndrome

BACKGROUND

Diarrheal irritable bowel syndrome (IBS-D), characterized primarily by the presence of diarrhea and abdominal pain, is a clinical manifestation resulting from a multitude of causative factors. Furthermore, Sishen Wan (SSW) has demonstrated efficacy in treating IBS-D. Nevertheless, its mechanism of action remains unclear.

METHODS

A model of IBS-D was induced by a diet containing 45 % lactose and chronic unpredictable mild stress. Additionally, the impact of SSW was assessed by measuring body weight, visceral sensitivity, defecation parameters, intestinal transport velocity, intestinal neurotransmitter levels, immunohistochemistry, and transmission electron microscopy analysis. Immunofluorescent staining was used to detect the expression of Mucin 2 (MUC2) and Occludin in the colon. Western blotting was used to detect changes in proteins related to tight junction (TJ), autophagy, and endoplasmic reticulum (ER) stress in the colon. Finally, 16S rRNA amplicon sequencing was used to monitor the alteration of gut microbiota after SSW treatment.

RESULTS

Our study revealed that SSW administration resulted in reduced visceral sensitivity, improved defecation parameters, decreased intestinal transport velocity, and reduced intestinal permeability in IBS-D mice. Furthermore, SSW promotes the secretion of colonic mucus by enhancing autophagy and inhibiting ER stress. SSW treatment caused remodeling of the gut microbiome by increasing the abundance of Blautia, Muribaculum and Ruminococcus torques group.

CONCLUSION

SSW can improve intestinal barrier function by promoting autophagy and inhibiting ER stress, thus exerting a therapeutic effect on IBS-D.

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.

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.

Ginsenoside Rk3 Regulates Tryptophan Metabolism along the Brain-Gut Axis by Targeting Tryptophan Hydroxylase and Remodeling the Intestinal Microenvironment to Alleviate Depressive-Like Behavior in Mice

Depression is a neuropsychiatric disease that significantly impacts the physical and mental health of >300 million people worldwide and places a major burden on society. Ginsenosides are the main active ingredient in ginseng and have been proven to have various pharmacological effects on the nervous system. Herein, we investigated the antidepressant effect of ginsenoside Rk3 and its underlying mechanism in a murine model of depression. Rk3 significantly improved depression-like behavior in mice, ameliorated the disturbance of the hypothalamus-pituitary-adrenal axis, and alleviated neuronal damage in the hippocampus and prefrontal cortex of mice. Additionally, Rk3 improved the abnormal metabolism of tryptophan in brain tissue by targeting tryptophan hydroxylase, thereby reducing neuronal apoptosis and synaptic structural damage in the mouse hippocampus and prefrontal cortex. Furthermore, Rk3 reshaped the composition of the gut microbiota of mice and regulated intestinal tryptophan metabolism, which alleviated intestinal barrier damage. Thus, this study provides valuable insights into the role of Rk3 in the tryptophan metabolic cycle along the brain-gut axis, suggesting that Rk3 may have the potential for treating depression.

Chicoric Acid Alleviates Colitis via Targeting the Gut Microbiota Accompanied by Maintaining Intestinal Barrier Integrity and Inhibiting Inflammatory Responses

Polyphenols have shown great potential to prevent ulcerative colitis. As a natural plant polyphenol, chicoric acid (CA) has antioxidant and anti-inflammatory properties. This study explored the intervention effects and potential mechanism of CA on dextran sodium sulfate (DSS)-induced colitis mice. The results showed that CA alleviated the symptoms of colitis and maintained the intestinal barrier integrity. CA significantly downregulated the mRNA expression levels of inflammatory factors including IL-6, IL-1β, TNF-α, IFN-γ, COX-2, and iNOS. In addition, CA modulated the gut microbiota by improving the microbial diversity, reducing the abundance of Gammaproteobacteriaand Clostridium_XI and increasing the abundance ofBarnesiellaandLachnospiraceae. Further fecal microbiota transplantation experiments showed that FM from CA donor mice significantly alleviated the symptoms of colitis, verifying the key role of gut microbiota. These results indicate that CA effectively relieves DSS-induced colitis via targeting gut microbiota along with preserving intestinal barrier function and suppressing inflammatory responses.

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.

Microbiota-accessible fiber activates short-chain fatty acid and bile acid metabolism to improve intestinal mucus barrier in broiler chickens

IMPORTANCE

The intestinal mucus barrier, located at the interface of the intestinal epithelium and the microbiota, is the first line of defense against pathogenic microorganisms and environmental antigens. Dietary polysaccharides, which act as microbiota-accessible fiber, play a key role in the regulation of intestinal microbial communities. However, the mechanism via which dietary fiber affects the intestinal mucus barrier through targeted regulation of the gut microbiota is not clear. This study provides fundamental evidence for the benefits of dietary fiber supplementation in broiler chickens through improvement in the intestinal mucus barrier by targeted regulation of the gut ecosystem. Our findings suggest that the microbiota-accessible fiber-gut microbiota-short-chain fatty acid/bile acid axis plays a key role in regulating intestinal function.

Wheat Bran Polyphenols Ameliorate DSS-Induced Ulcerative Colitis in Mice by Suppressing MAPK/NF-κB Inflammasome Pathways and Regulating Intestinal Microbiota

Wheat bran (WB) is the primary by-product of wheat processing and contains a high concentration of bioactive substances such as polyphenols. This study analyzed the qualitative and quantitative components of polyphenols in wheat bran and their effects on ulcerative colitis (UC) using the dextran sulfate sodium (DSS)-induced colitis model in mice. The potential mechanism of wheat bran polyphenols (WBP) was also examined. Our findings indicate that the main polyphenol constituents of WBP were phenolic acids, including vanillic acid, ferulic acid, caffeic acid, gallic acid, and protocatechuic acid. Furthermore, WBP exerted remarkable protective effects against experimental colitis. This was achieved by reducing the severity of colitis and improving colon morphology. Additionally, WBP suppressed colonic inflammation via upregulation of the anti-inflammatory cytokine IL-10 and downregulation of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) in colon tissues. Mechanistically, WBP ameliorated DSS-induced colitis in mice by inhibiting activation of the MAPK/NF-κB pathway. In addition, microbiome analysis results suggested that WBP modulated the alteration of gut microbiota caused by DSS, with an enhancement in the ratio of Firmicutes/Bacteroidetes and adjustments in the number of Helicobacter, Escherichia-Shigella, Akkermansia, Lactobacillus, Lachnospiraceae_NK4A136_group at the genus level. To conclude, the findings showed that WBP has excellent prospects in reducing colonic inflammation in UC mice.

A novel Sagittaria sagittifolia L. polysaccharides mitigate DSS-induced colitis via modulation of gut microbiota and MAPK/NF-κB signaling pathways

Sagittaria sagittifolia L. polysaccharides possess anti-inflammatory, antioxidant, and immune-modulatory properties. In this study, we identified a novel S. sagittifolia L. polysaccharide, named PSSP-1, and evaluated its potential in alleviating dextran sulfate sodium (DSS)-induced colitis in a mouse model. The results demonstrated that administration of PSSP-1 at doses of 100, 200, and 400 mg/kg·bw significantly reduced the disease activity index (DAI) and suppressed the expression of inflammatory cytokines in UC mice. Furthermore, PSSP-1 treatment upregulated the expression levels of claudin-1, occludin, and ZO-1, and promoted the diversity and abundance of beneficial gut microbiota, including Lactobacillus and Candidatus_Saccharimonas, while reducing the levels of Bacteroidetes and Verrucomicrobiota. Particularly, the Lactobacillus_johnsonii species may play a potentially significant role in modulating colitis. Subsequently, there was a significant increase in the levels of short-chain fatty acids (SCFAs). Additionally, the correlation analyses revealed positive associations between PSSP-1 supplementation and Nitrosospira and Dialister, which are implicated in gut inflammation. Mechanistically, PSSP-1 intervention inhibited the protein phosphorylation of key molecules in the MAPK and NF-κB signaling pathways. Collectively, these findings suggest that PSSP-1 mitigates colitis symptoms by repairing the intestinal barrier, promoting microbial metabolism, and regulating the gut microbiota-MAPK/NF-κB signaling pathways.

Phenolics from Dendrobium officinale Leaf Ameliorate Dextran Sulfate Sodium-Induced Chronic Colitis by Regulating Gut Microbiota and Intestinal Barrier

The increasing incidence of colitis and the side effects of its therapeutic drugs have led to the search for compounds of natural origin, including phenolics, as new treatments for colitis. In this study, the potential mechanism of Dendrobium officinale leaf phenolics (DOP) on the relief of dextran sulfate sodium (DSS)-induced colitis was explored. The results showed that DOP treatment for 36 days reduced the symptoms of colitis caused by DSS, including reduction of the disease activity index and alleviation of colonic tissue damage. In addition, DOP downregulated the expression of key proteins of the TLR4/NF-κB signaling pathway and reduced the production of inflammatory cytokines. Furthermore, DOP could enhance the expression of tight junction proteins including ZO-1, Occludin, and Claudin-1 to restore intestinal mucosal barrier function. DOP also effectively regulates disordered intestinal flora and enhances the production of short-chain fatty acids, which is also beneficial in modulating gut internal environmental homeostasis, inhibiting inflammation, and restoring the intestinal barrier. These findings indicated that DOP can ameliorate DSS-induced chronic colitis by regulating gut microbiota, intestinal barrier, and inflammation, and it is a promising ingredient from D. officinale.

Coptis chinensis and Berberine Ameliorate Chronic Ulcerative Colitis: An Integrated Microbiome-Metabolomics Study

Coptis chinensis Franch (RC), has historically been used for the treatment of "Xiao Ke" and "Xia Li" symptoms in China. "Xia Li" is characterized by abdominal pain and diarrhea, which are similar to the clinical symptoms of ulcerative colitis (UC). For the first time, this study aims to compare the anti-colitis effects of berberine (BBR) and total RC alkaloids (TRCA) and investigate the underlying metabolites and gut microbiota biomarkers. Metabolomics results showed that several colitis-related biomarkers, including lysophosphatidyl ethanolamine, lysophosphatidylcholine, scopolamine-methyl-bromide, N1-methyl-2-pyridone-5-carboxamide, 4-hydroxyretinoic acid, and malic acid, were significantly improved in model mice after BBR and TRCA treatments. High-dose BBR and TRCA treatments reversed the mouse colon shortening caused by dextran sodium sulfate (DSS), alleviated bowel wall swelling, and reduced inflammatory cell infiltration. BBR and TRCA restored the damaged mucosa integrity in colitis mice by upregulating claudin 1 and occludin, preventing colon epithelium apoptosis by inhibiting the cleavage of caspase 3. Additionally, BBR and TRCA significantly decreased the richness of the pathogenic bacteria Bacteroides acidifaciens but increased the abundance of the probiotic Lactobacillus spp. Notably, TRCA exhibited superior anti-colitis effects to those of BBR. Thus, this agent warrants further study and application in the treatment of inflammatory bowel disease in the clinic.

Epigallocatechin Gallate Alleviates Staphylococcal Enterotoxin A-Induced Intestinal Barrier Damage by Regulating Gut Microbiota and Inhibiting the TLR4-NF-κB/MAPKs-NLRP3 Inflammatory Cascade

Natural phytochemicals have attracted increasing attention because of their promising ability to tackle bacteriotoxin-induced public safety concerns. However, it is unclear how natural phytochemicals regulate the intestinal barrier dysfunction caused by bacteriotoxin, such as staphylococcal enterotoxin A (SEA). This study aims to illustrate the in vitro and in vivo protective mechanism of epigallocatechin gallate (EGCG) on SEA-triggered intestinal barrier damage and inflammation. Results show that EGCG alleviates intestinal barrier damage by effectively inhibiting SEA-induced intestinal permeability increase, tight junction protein and mucin loss, and intestinal cell apoptosis. EGCG also reduces intestinal inflammation by suppressing the TLR4-NF-κB/MAPKs-NLRP3 pathway. Importantly, EGCG reverses gut microbiota dysbiosis and short-chain fatty acid (SCFA) content decrease induced by SEA. It is worth noting that this study also detects the direct interaction between the phytochemical and virulence factors and finds that EGCG effectively not only inhibits the secretion of SEA but also binds with the secreted SEA to attenuate its toxicity. Taken together, EGCG mitigates SEA-induced intestinal barrier dysfunction via gut microbiota SCFA-mediated TLR4-NF-κB/MAPKs-NLRP3 inflammatory cascade inhibition. Overall, this research provides enlightening insight into the application of bacteriotoxin-targeting natural compounds in the field of food safety and human wellness.

Glycated Casein by TGase-Type Exerts Protection Potential against DSS-Induced Colitis via Inhibiting TLR4/NF-κB Signaling Pathways in C57BL/6J Mice

Glycation by transglutaminase (TGase)-type could effectively improve the structure and functional properties of proteins. However, the influence on intestinal inflammation or the underlying mechanisms has not been investigated. The goal of this research was to compare the bioactivities between glycated casein generated from the TGase-catalyzed reaction and oligochitosan as well as casein using a mouse model of dextran sulfate sodium (DSS)-induced intestinal inflammation to examine the protective effects and the underlying mechanism of glycated casein on intestinal inflammation. Eight groups of C57BL/6 mice were randomly assigned in this study: Control group: standard diet for 35 days; Model group: standard diet for 28 days and then colitis induction; Pretreated groups: different levels (200, 400, 800 mg/kg BW) of casein or glycated casein for 28 days before colitis induction. The mice were drinking water containing a 3% DSS solution for seven days of mice to cause colitis. The results indicated that glycated casein and casein at 200-800 mg/kg BW all relieved DSS-induced weight loss, reduced disease activity index (DAI) score, alleviated colon length shortening, weakened the destruction of colonic mucosal structure, decreased serum LPS, and MPO, IL-1β, IL-6 and TNF-α levels in serum and colon, as well as regulated the expression of proteins involved in the TLR4/NF-κB signaling pathway in a concentration-dependent manner. Glycated caseinate showed a better protective effect against DSS-induced colitis than casein, highlighting that the TGase-type glycation of proteins as a potential functional food ingredient might be a helpful method for gut health.

NOD-like receptors mediate homeostatic intestinal epithelial barrier function: promising therapeutic targets for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic gastrointestinal inflammatory disease that involves host genetics, the microbiome, and inflammatory responses. The current consensus is that the disruption of the intestinal mucosal barrier is the core pathogenesis of IBD, including intestinal microbial factors, abnormal immune responses, and impaired intestinal mucosal barrier. Cumulative data show that nucleotide-binding and oligomerization domain (NOD)-like receptors (NLRs) are dominant mediators in maintaining the homeostasis of the intestinal mucosal barrier, which play critical roles in sensing the commensal microbiota, maintaining homeostasis, and regulating intestinal inflammation. Blocking NLRs inflammasome activation by botanicals may be a promising way to prevent IBD progression. In this review, we systematically introduce the multiple roles of NLRs in regulating intestinal mucosal barrier homeostasis and focus on summarizing the activities and potential mechanisms of natural products against IBD. Aiming to propose new directions on the pathogenesis and precise treatment of IBD.

Galactooligosaccharide or 2'-Fucosyllactose Modulates Gut Microbiota and Inhibits LPS/TLR4/NF-κB Signaling Pathway to Prevent DSS-Induced Colitis Aggravated by a High-Fructose Diet in Mice

A high-fructose diet (HFrD) has been reported to exacerbate dextran sulfate sodium (DSS)-induced colitis. 2'-Fucosyllactose (FL) and galactooligosaccharide (GOS) have been shown, respectively, to have preventive and ameliorative effects on colitis, while limited research has explored whether GOS and FL may be equally protective or preventive in mice with HFrD. Here, we evaluated the protective effects of FL and GOS on colitis exacerbated by feeding HFrD and explored the underlying mechanisms. DSS-induced colitis was studied in four randomized C57BL/6J male mice (n = 8 mice/group). Among them, three groups were fed with HFrD, and two received either GOS or FL treatment, respectively. Gut microbial composition was analyzed by 16S rDNA gene sequencing. Intestinal barrier integrity and inflammatory pathway expression were measured using qPCR, immunofluorescence, and Western blot methods. Compared to the HFrD group, GOS or FL treatment increased the α-diversity of the gut microbiota, reduced the relative abundance of Akkermansia, and increased the content of short-chain fatty acids (SCFAs), respectively. Compared with the HFrD group, GOS or FL treatment improved the loss of goblet cells and the reduction of tight junction protein expression, thereby improving intestinal barrier integrity. Also, GOS or FL inhibited the LPS/TLR4/NF-κB signaling pathway and oxidative stress to suppress the inflammatory cascade compared with the HFrD group. These findings suggest that GOS or FL intake can alleviate HFrD-exacerbated colitis, with no significant difference observed between GOS and FL treatments.

The Effects of Synbiotics on Dextran-Sodium-Sulfate-Induced Acute Colitis: The Impact of Chitosan Oligosaccharides on Endogenous/Exogenous Lactiplantibacillus plantarum

In this work, Lactiplantibacillus plantarum (L. plantarum) isolated from mice feces (LP-M) and pickles (LP-P) were chosen as the endogenous and exogenous L. plantarum, respectively, which were separately combined with chitosan oligosaccharides (COS) to be synbiotics. The anti-inflammatory activity of LP-M, LP-P, COS, and the synbiotics was explored using dextran-sodium-sulfate (DSS)-induced acute colitis mice, as well as by comparing the synergistic effects of COS with LP-M or LP-P. The results revealed that L. plantarum, COS, and the synbiotics alleviated the symptoms of mice colitis and inhibited the changes in short-chain fatty acids (SCFAs), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, IL-10, and myeloperoxidase (MPO) caused by DSS. In addition, the intervention of L. plantarum, COS, and the synbiotics increased the relative abundance of beneficial bacteria Muribaculaceae and Lactobacillus and suppressed the pathogenic bacteria Turicibacter and Escherichia-Shigella. There was no statistically difference between LP-M and the endogenous synbiotics on intestinal immunity and metabolism. However, the exogenous synbiotics improved SCFAs, inhibited the changes in cytokines and MPO activity, and restored the gut microbiota more effectively than exogenous L. plantarum LP-P. This indicated that the anti-inflammatory activity of exogenous LP-P can be increased by combining it with COS as a synbiotic.