Rosmarinic Acid Restores Colonic Mucus Secretion in Colitis Mice by Regulating Gut Microbiota-Derived Metabolites and the Activation of Inflammasomes

Temperature-dependent convection induced incremental extraction of anthocyanins from Melastoma dodecandrum Lour. Based on recyclable natural deep eutectic system

Melastoma dodecandrum Lour. (MDL) contains abundant anthocyanins. Choline chloride-oxalic acid (ChCl-OA, 1:1) was selected for the temperature-dependent convection induced incremental extraction of anthocyanins from MDL. The regulating effects of MDL anthocyanins on gut microbiota were studied by analyzing the diversity in C57BL/6 J mice. The results showed that under optimized conditions (ultrasonic power of 310.4 W, extraction temperature of 59.9 °C, cold-stimulation time of 9.0 min, extraction time of 29.8 min), the yield of anthocyanins (YA) achieved the highest level at 60.28 ± 1.05 mg CGE/g DW, outperforming non-incremental approach by 58 %. The ratio of YA obtained from the fifth regeneration of ChCl-OA to initial YA was over 90 %. Eight anthocyanins were identified in incremental extracts, over four anthocyanins in non-incremental extracts. The ChCl-OA system achieved equilibrium at 3.5 ps with energy of -1002.22 kcal/mol. More hydrogen bonds number (128) and longer lifetime (6.72 ps) resulted in a larger diffusion coefficient of anthocyanins at 0.10 m2/s. The 60 mg/mL of anthocyanins increased the α-Diversity (Sobs) and Gut Microbiome Health Index (GMHI) by 22 % and 56 %, respectively, harmonizing the gut microbiota. Therefore, this recyclable ChCl-OA based incremental extraction has unveiled horizons for the green and sustainable production of MDL anthocyanins.

Combating depression with rosemary (Rosmarinus officinalis L.)-derived polyphenols: Major phytochemicals, functional properties, and potential

Depression is a common mental condition with high prevalence and recurrence rates worldwide. The active polyphenols in Rosmarinus officinalis L. contain several pharmacological activities, including anti-inflammatory, antibacterial, and neuroprotective characteristics. However, the effects of rosemary polyphenols on depression have not been thoroughly studied. The anti-inflammatory activity and regulatory effects on gut microbiota of key rosemary polyphenols, as well as their impacts on depression, are the main emphasis of this research. We conclude that the anti-depressive effects of rosemary polyphenols are due to anti-inflammatory properties and bidirectional relationship with gut microbiota, including inhibiting inflammatory pathways and cytokines (reducing pro-inflammation cytokines, suppressing NF-κB and NLRP3 inflammasomes, and upregulating Nrf2/HO-1 pathway), altering intestinal microbiota structure and metabolites (polyphenols-related microbial metabolites and biotransformation of polyphenols by microbiota). This paper provides a better understanding of the anti-depressive effects of polyphenols in Rosmarinus officinalis L.

Isobutyrate Confers Resistance to Inflammatory Bowel Disease through Host-Microbiota Interactions in Pigs

Supplementation with short-chain fatty acids (SCFAs) is a potential therapeutic approach for inflammatory bowel disease (IBD). However, the therapeutic effects and mechanisms of action of isobutyrate in IBD remain unclear. Clinical data indicate that the fecal levels of isobutyrate are markedly lower in patients with Crohn's disease than in healthy controls. Compared with healthy mice and healthy pigs, mice and pigs with colitis presented significantly lower isobutyrate levels. Furthermore, the level of isobutyrate in pigs was significantly negatively correlated with the disease activity index. We speculate that isobutyrate may play a crucial role in regulating host gut homeostasis. We established a model of dextran sulfate sodium-induced colitis in pigs, which have gastrointestinal structure and function similar to those of humans; we performed multiomic analysis to investigate the therapeutic effects and potential mechanisms of isobutyrate on IBD at both the animal and cellular levels and validated the results. Phenotypically, isobutyrate can significantly alleviate diarrhea, bloody stools, weight loss, and colon shortening caused by colitis in pigs. Mechanistically, isobutyrate can increase the relative abundance of Lactobacillus reuteri, thereby increasing the production of indole-3-lactic acid, regulating aryl hydrocarbon receptor expression and downstream signaling pathways, and regulating Foxp3+ CD4+ T cell recruitment to alleviate colitis. Isobutyrate can directly activate G protein-coupled receptor 109A, promote the expression of Claudin-1, and improve intestinal barrier function. In addition, isobutyrate can increase the production of intestinal SCFAs and 3-hydroxybutyric acid and inhibit the TLR4/MyD88/NF-κB signaling pathway to suppress intestinal inflammation. In conclusion, our findings demonstrate that isobutyrate confers resistance to IBD through host-microbiota interactions, providing a theoretical basis for the use of isobutyrate in alleviating colitis.

Crosstalk Between Bile Acids and Intestinal Epithelium: Multidimensional Roles of Farnesoid X Receptor and Takeda G Protein Receptor 5

Bile acids and their corresponding intestinal epithelial receptors, the farnesoid X receptor (FXR), the G protein-coupled bile acid receptor (TGR5), play crucial roles in the physiological and pathological processes of intestinal epithelial cells. These acids and receptors are involved in the regulation of intestinal absorption, signal transduction, cellular proliferation and repair, cellular senescence, energy metabolism, and the modulation of gut microbiota. A comprehensive literature search was conducted using PubMed, employing keywords such as bile acid, bile acid receptor, FXR (nr1h4), TGR5 (gpbar1), intestinal epithelial cells, proliferation, differentiation, senescence, energy metabolism, gut microbiota, inflammatory bowel disease (IBD), colorectal cancer (CRC), and irritable bowel syndrome (IBS), with a focus on publications available in English. This review examines the diverse effects of bile acid signaling and bile receptor pathways on the proliferation, differentiation, senescence, and energy metabolism of intestinal epithelial cells. Additionally, it explores the interactions between bile acids, their receptors, and the microbiota, as well as the implications of these interactions for host health, particularly in relation to prevalent intestinal diseases. Finally, the review highlights the importance of developing highly specific ligands for FXR and TGR5 receptors in the context of metabolic and intestinal disorders.

The effects of repeated fecal transplantation and activated charcoal treatment on gut dysbiosis induced by concurrent ceftriaxone administration in mice

BACKGROUND

Antibiotic treatment contributes to gut microbiota dysbiosis. Previous studies have shown that fecal microbiota transplantation (FMT), fecal filtrate (FF), and activated charcoal (AC) treatments can prevent gut microbiota disturbances caused by antibiotics or Clostridioides difficile infection. However, these treatments have typically been limited to restoring gut microbiota after dysbiosis, and antibiotics must be discontinued beforehand. Here, we investigated the protective effects of these treatments on gut microbiota to prevent dysbiosis during concurrent systemic ceftriaxone administration.

METHODS

C57BL/6 mice that received intraperitoneal ceftriaxone for seven consecutive days were concomitantly treated with AC, FMT, FMT + AC, FF, or FF + AC via oral gavage. Gut microbiomes were analyzed using 16 S rRNA gene sequencing, and intestinal mucosal pathology was evaluated through H&E staining.

RESULTS

Systemic ceftriaxone administration significantly altered gut microbiota diversity and composition but did not affect intestinal mucosal histology. Alpha and beta diversity analyses showed that microbiota diversity decreased in all ceftriaxone-treated groups, with the ceftriaxone + FF + AC group retaining the highest diversity. The ceftriaxone + AC group had higher Enterococcus but lower Muribaculaceae relative abundances than the control (no ceftriaxone), ceftriaxone only, and ceftriaxone + FF + AC groups.

CONCLUSIONS

These results show that fecal filtrate transplantation combined with activated charcoal treatment may help balance gut microbiota diversity and reduce the presence of resistant bacteria during ceftriaxone exposure.

A systematic review on the role of gut microbiome in inflammatory bowel disease: Spotlight on virome and plant metabolites

Inflammatory bowel diseases (IBD), including ulcerative colitis and Crohn's disease, arise from various factors such as dietary, genetic, immunological, and microbiological influences. The gut microbiota plays a crucial role in the development and treatment of IBD, though the exact mechanisms remain uncertain. Current research has yet to definitively establish the beneficial effects of the microbiome on IBD. Bacteria and viruses (both prokaryotic and eukaryotic) are key components of the microbiome uniquely related to IBD. Numerous studies suggest that dysbiosis of the microbiota, including bacteria, viruses, and bacteriophages, contributes to IBD pathogenesis. Conversely, some research indicates that bacteria and bacteriophages may positively impact IBD outcomes. Additionally, plant metabolites play a crucial role in alleviating IBD due to their anti-inflammatory and microbiome-modulating properties. This systematic review discusses the role of the microbiome in IBD pathogenesis and evaluates the potential connection between plant metabolites and the microbiome in the context of IBD pathophysiology.

Effects of Ficus carica L. polysaccharide on the intestinal immune function and microbiota of broilers

Introduction

Ficus carica L. polysaccharides (FLPs) are groups of biologically active compounds extracted from Ficus carica L.

Methods

In this study, we analyzed the structure of FLPs, predicted their immune enhancement pathway, and detected the impact of FLPs on the growth performance, immune function, and intestinal microflora of broiler chickens.

Results

The results showed that FLPs are comprised of monosaccharides including rhamnose, arabinose, mannose, glucose, and galactose. Feeding with FLPs significantly promoted the growth performance, slaughtering performance, and immune organs index of chickens compared to the control group (p < 0.05). Moreover, the FLP-h and FLP-m groups had increased levels of sIgA, IgG, IL-4, IL-5, IL-12, and IFN-g; improved immunity and barrier function; and a higher percentage of spleen CD4+ and CD8+ T cell differentiation compared to the control group (p < 0.05). Additionally, the FLP-h group had increased levels of various SCFAs, and increased beneficial bacteria such as Firmicutes at the phylum level and Faecalibacterium, Blautia, Phascolarctobacterium, and Alistipes at the genus level. The results of network pharmacology and KEGG pathway prediction indicate that FLPs may change the structure and metabolism of intestinal microbiota by enhancing carbon fixation pathways in prokaryotes, and promote intestinal immune barrier function through the joint action of bisphenol degradation, retinol metabolism, NODlike signaling pathways, toll-like receptor signaling pathways, and the MAPK signaling pathway.

Discussion

These results suggest that FLP-h supplementation effectively promotes growth performance and enhances the intestinal mucosal immune barrier function in chickens.

Elucidating the mechanism of the first Chinese herbal formula Shuangxia Decoction to alleviate insomnia using multi-omics technologies

BACKGROUND

Shuangxia Decoction (SXD), evolved from " Banxia Shumi Decoction", is composed of Pinellia ternata (Thunb.) Makino and Prunella vulgarisl. SXD has been used to treat insomnia and is considered the first traditional Chinese herbal formula developed specifically for the treatment of insomnia.

PURPOSE

This study aimed to investigate the mechanism underlying SXD's effects against insomnia using multi-omics technologies.

METHODS

Network pharmacology was employed to predict the active components and core targets of SXD in treating insomnia, utilizing 17 active compounds. The pharmacodynamics of SXD were further validated in sleep-deprived mice. UPLC-QE-Orbitrap-MS was utilized to analyze serum metabolomics and hypothalamic tissue metabolomics of the sleep-deprived mice, revealing the biological mechanism of SXD against sleep deprivation. Rosmarinic acid (RA), a representative component of SXD, was selected to further investigate its anti-sleep deprivation mechanism, including intestinal ROS activity assays, intestinal metabolite analysis, serum metabolomics, gut microbiota analysis, and western blotting.

RESULTS

Through network pharmacology analysis, three active compounds and four targets were identified as key contributors to the therapeutic effects of SXD on insomnia. In the sleep deprivation (SD) model regulated by SXD, metabolomics studies revealed 28 differential serum metabolites and 20 differential metabolites in hypothalamic tissues. Among these, three shared differential metabolites (Hypoxanthine, Pyrroline hydroxycarboxylic acid, Hydroxyphenyllactic acid) and two critical metabolic pathways (purine metabolism and arginine and proline metabolism) were identified. In the SD model regulated by RA, varying doses of RA effectively reduced SD-induced ROS accumulation in both the small and large intestines. Analysis of RA metabolites in the intestines revealed 57 putative metabolites, most of which were oxidized products. Serum metabolomics analysis of RA against SD showed 58 differential metabolites, with purine metabolism and phenylalanine metabolism pathways being notably involved. Hypoxanthine was identified as a potential marker for clinical sleep deprivation by integrating serum and hypothalamic tissue metabolomics data from SXD and serum metabolomics data from RA. 16S rRNA sequencing demonstrated that SD significantly altered the abundance of eight gut microbiota species. RA exhibited a restorative effect on specific imbalanced gut microbiota, independent of dosage. Western blotting analysis revealed that RA preserved intestinal epithelial integrity by modulating the expression of tight junction proteins, including ZO-1, occludin and claudin. Meanwhile, RA effectively alleviated SD-induced oxidative stress by activating the Nrf2 signaling pathway, promoting nuclear translocation of Nrf2 and increasing the expression of its downstream antioxidant proteins HO-1 and NQO-1 in the small and large intestines.

CONCLUSION

Our study demonstrates that SXD has significant efficacy in alleviating SD. RA, as the representative compound of SXD, can eliminate the accumulation of intestines ROS in SD mice and improve gut microbiota imbalance caused by oxidative stress by upregulating tight junction proteins ZO-1, Occludin, and Claudin, and regulating the Nrf2 signaling pathway. Furthermore, hypoxanthine has been identified as a promising and reliable biomarker for SD.

Microfluidic-derived montmorillonite composite microparticles for oral codelivery of probiotic biofilm and postbiotics

Oral delivery of probiotics has shown promising effects in modulating the gut microbiota and treating ulcerative colitis (UC). However, the therapeutic efficacy is restricted by gastrointestinal assaults, poor mucosal adhesion, and single therapeutic modality. Here, we developed acid-resistant, gut-environment-responsive composite microparticles based on microfluidic electrospray for the oral codelivery of probiotic [Lactobacillus acidophilus (LA)] biofilm and postbiotics (indole-3-propionic acid). Montmorillonite was selected for supporting biofilm formation due to its cation-exchange capability and clearly defined biosafety. The montmorillonite-LA biofilm was effectively protected by the microparticles and markedly improved the intestinal retention. Upon oral administration, the composite microparticles notably alleviated colitis in mice, including reducing the inflammatory response, improving intestinal barrier function, and modulating the gut microbiota. Consequently, the composite microparticles show high potential for enhancing probiotic delivery efficacy and present a promising strategy for UC treatment.

Anxiolytic, Antidepressant and Healthy Sleep-Promoting Potential of Rosmarinic Acid: Mechanisms and Molecular Targets

The etiology of psychiatric disorders is complex and results from intricate interactions among multiple neurobiological, psychological, environmental, and genetic factors. Furthermore, the roles of gut microbiome dyshomeostasis in their pathogeneses are just beginning to be uncovered, adding to another level of complexity. In recent years, significant efforts have been directed toward discovering multimodal yet safe therapeutics to counteract psychological deficits. Rosmarinic acid (RA), a polyphenol found in several medicinal herbs, has received considerable attention as a potential multifaceted therapeutic agent, particularly for neuropsychiatric conditions. In order to critically evaluate this aspect, data was compiled and consolidated after extensive searches on scholarly databases like PubMed, Google Scholar, and Web of Science. Peer-reviewed publications which focused on RA as a therapeutic agent for psychiatric disorders were included regardless of the year of publication and country of origin. Based on pre-clinical and clinical evidence, this review delves into the various mechanistic aspects of the antidepressant, anxiolytic, and sleep-promoting functions of RA. The beneficial effects of RA on the gut-microbiome-brain (GMB) axis and their implications for the regulation of neuroprotective pathways are also discussed, with a particular focus on exploiting them to ameliorate neuropsychiatric conditions. Our assessment indicated that RA is a multimodal neuroprotectant against psychiatric conditions and beneficially influences a plethora of targets related to redox, inflammatory, synaptic, cell death, neurotrophic, and cell signaling pathways. As a dietary agent, RA may also be relevant in favorably altering the GMB axis, indicating its prospects as a potential multimodal adjuvant therapeutic agent in regulating the pathogenic mechanisms underlying neuropsychiatric conditions. However, more extensive clinical studies are required to ascertain the neuromodulatory actions of RA in neuronal pathophysiologies, including psychiatric ailments.

Runchangningshen paste activates NLRP6 inflammasome-mediated autophagy to stimulate colonic mucin-2 secretion and modulates mucosal microbiota in functional constipation

BACKGROUND

Runchangningshen paste (RCNSP) is a paste made of four medicinal and edible homologous Chinese medicine mixed with honey. It is known for its ability to nourish yin and blood as well as to loosen the bowel to relieve constipation. The pathophysiology of functional constipation (FC) is associated with a reduction in mucin-2 (MUC2) secretion and microbial dysbiosis.

AIM

To investigate the underlying mechanism of RCNSP against FC through MUC2 and the gut mucosal microbiota.

METHODS

Ultra-performance liquid chromatography tandem mass spectrometry characterized RCNSP composition to elucidate the material basis of action. FC model was induced via loperamide gavage (16 mg/kg) twice daily for 7 days. Applying defecation function and gastrointestinal motility to assess constipation severity. Hematoxylin and eosin and Alcian blue-periodic acid-schiff staining analyzed colonic mucosal morphology. Transmission electron microscope was used to observe the ultrastructure of goblet cells (GCs). Immunofluorescence colocalization, quantitative PCR, and western blot assessed the impact of RCNSP on gene and protein expression within the NLRP6/autophagy pathway. 16S rDNA was employed to sequence the gut mucosal microbiota.

RESULTS

RCNSP contained 12 components with potential laxative effects. It enhanced defecation function, accelerated gastrointestinal motility, and maintained colonic mucosal integrity. RCNSP treatment significantly increased GC abundance and MUC2 production while preserving GC ultrastructure. At the molecular level, RCNSP enhanced the colocalized expression of key regulatory proteins and modulated mRNA and protein expressions in the NLRP6/autophagy pathway. Through 16S rDNA sequencing analysis, RCNSP significantly altered the mucosal microbiota composition. Specifically, it increased beneficial bacterial strains while reducing harmful ones. Simultaneously, RCNSP reduced butyrate-producing bacteria like Proteobacteria, Enterobacteriaceae, Blautia, and Eubacterium and decreased hydrogen sulfide-producing species, such as Prevotellaceae. It also reduced bile acid-inhibiting species, such as g_Eubacter_coprostanoligenes_group and Erysipelotrichaceae while increasing bile acid-producing species, such as Colidextribacter.

CONCLUSION

Our findings suggested that RCNSP ameliorated constipation through a dual mechanism: It stimulated colonic MUC2 secretion by activating NLRP6 inflammasome-mediated autophagy and modulated the composition of the mucosal microbiota.

Amelioration of Obesity-Related Disorders in High-Fat Diet-Fed C57BL/6 Mice Following Fecal Microbiota Transplantation From DL-Norvaline-Dosed Mice

Fecal microbiota transplantation (FMT) could significantly alter the recipient's gut bacteria composition and attenuate obesity and obesity-related metabolic syndromes. DL-norvaline is a nonproteinogenic amino acid and possesses anti-obesity potential. However, the specific mechanisms by which gut microbiota might mediate beneficial effects of DL-norvaline have not been completely elucidated. In this study, DL-norvaline-mediated FMT upregulated the beneficial bacteria (Clostridia_UCG_014, Christensenellales, Bacilli, Ileibacterium, Dubosiella, Lactobacillus, Muribaculaceae, and Bacteroidaceae) and downregulated the harmful bacteria (Tuzzerella and Marinifilaceae), further intestinal inflammation, oxidative stress, and intestinal barrier were alleviated as well as short chain fatty acids levels were increased, thus alleviating glucose and insulin metabolism, improving biochemical indexes and energy metabolism and decreasing body weight gain and tissue weight. However, heat-inactivated FMT did not demonstrate any of those improvements in obese mice. Notably, both DL-norvaline-mediated FMT and heat-inactivated FMT increased Bacteroidaceae and Muribaculaceae, this being a signature of alterations to the gut microbiota marker caused by DL-norvaline. Therefore, the beneficial effects of DL-norvaline were transmissible via FMT. This study highlighted the pivotal involvement of the gut microbiota in the development of obesity and provided a novel insight into the underlying mechanisms of FMT, thereby potentially enhancing the efficacy and refinement of FMT utilization.

Bile acids as signaling molecules in inflammatory bowel disease: Implications for treatment strategies

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammatory bowel disease (IBD) is a globally increasing disease. Despite continuous efforts, the clinical application of treatment drugs has not achieved satisfactory success and faces limitations such as adverse drug reactions. Numerous investigations have found that the pathogenesis of IBD is connected with disturbances in bile acid circulation and metabolism. Traditional Chinese medicine targeting bile acids (BAs) has shown significant therapeutic effects and advantages in treating inflammatory bowel disease.

AIM OF THIS REVIEW

IThis article reviews the role of bile acids and their receptors in IBD, as well as research progress on IBD therapeutic drugs based on bile acids. It explores bile acid metabolism and its interaction with the intestinal microbiota, summarizes clinical drugs for treating IBD including single herbal medicine, traditional herbal prescriptions, and analyzes the mechanisms of action in treating IBD.

MATERIALS AND METHODS

IThe electronic databases such as PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI) have been utilized to retrieve relevant literature up to January 2024, using keywords "bile acid", "bile acid receptor", "inflammatory bowel disease", "intestinal microbiota" and "targeted drugs".

RESULTS

IImbalance in bile acid levels can lead to intestinal inflammation, while IBD can disrupt the balance of microbes, result in alterations in the bile acid pool's composition and amount. This change can damage of intestinal mucosa healing ability. Bile acids are vital for keeping the gut barrier function intact, regulating gene expression, managing metabolic equilibrium, and influencing the properties and roles of the gut's microbial community. Consequently, focusing on bile acids could offer a potential treatment strategy for IBD.

CONCLUSION

IIBD can induce intestinal homeostasis imbalance and changes in BA pool, leading to fluctuations in levels of relevant metabolic enzymes, transporters, and nuclear receptors. Therefore, by regulating the balance of BA and key signaling molecules of bile acids, we can treat IBD. Traditional Chinese medicine has great potential and promising prospects in treating IBD. We should focus on the characteristics and advantages of Chinese medicine, promote the development and clinical application of innovative Chinese medicine, and ultimately make Chinese medicine targeting bile acids the mainstream treatment for IBD.

Type 5 Resistant Starch Can Effectively Alleviate Experimentally Induced Colitis in Mice by Modulating Gut Microbiota

Resistant starch (RS) has been shown to modulate intestinal microbiota in animal models in ways that could reduce the effects of dysbiosis-related diseases. However, the mechanism of how this is achieved is not understood. The present study aimed to reveal the mechanism of how RS mitigates dextran sulfate sodium (DSS)-induced colitis in mice by using a starch-lipid complex (RS type 5), with an RS type 2 from high-amylose maize starch as a comparison. Both RS5 and RS2 induced changes in the diversity and composition of the gut bacteria, leading to the alleviation of the induced colitis symptoms including decreasing the loss in body weight, disease activity index score, and colonic shortening. The levels of inflammatory cytokines were modulated and accompanied by an increase in goblet cell numbers and thickening of the intestinal mucus layer. RS5 was more effective, compared to RS2, in alleviating all of the colitis symptoms, mainly through improving the gut microflora dysbiosis and stimulating the generation of short-chain fatty acids (SCFAs). Our study shows that RS5 could effectively alleviate the symptoms of colitis, highlighting a potential use for RS5, particularly in relieving inflammatory bowel disease.

Bile Acids in Inflammatory Bowel Disease: From Pathophysiology to Treatment

Inflammatory bowel disease (IBD) is a chronic condition that affects about 7 million people worldwide, and new therapies are needed. Understanding the complex roles that bile acids (BAs) play in IBD may lead to the development of novel IBD treatments independent of direct immunosuppression. This review discusses the latest discoveries in the roles BAs play in IBD pathogenesis and explores how these discoveries offer promising new therapeutic targets to treat IBD and improve patient outcomes. Several therapies discussed include specific BA receptor (BAR) agonists, dietary therapies, supplements, probiotics, and mesenchymal stem cell therapies that have all been shown to decrease IBD disease activity.

Rosmarinic acid alleviated intestinal barrier damage caused by Escherichia coli by regulating the gut microbiota and inhibiting the NF-κB signalling pathway in mice

Escherichia coli (E. coli) is a common zoonotic foodborne pathogen that poses a major threat to public health and economic development. Rosmarinic acid (RA) can inhibit intestinal inflammation; however, the protective effect of RA against the intestinal barrier damage induced by E. coli in mice and the underlying mechanism have not been elucidated. In this study, mice were orally administered with RA (20 mg kg-1) by gavage for one week and then were intraperitoneally challenged with E. coli. Mouse colonic epithelial cells (MCECs) were pretreated with RA for 6 h and challenged with E. coli (MOI = 1000) for 3 h. The results revealed that RA alleviated E. coli-induced weight loss in mice; reduced the increase in the levels of TNF-α, IL-6 and IL-1β in the serum; alleviated the decrease in ZO-1 protein expression; and increased intestinal permeability by inhibiting the NF-κB signalling pathway both in vivo and in vitro. Moreover, RA relieved the increase in intestinal permeability, reversed the structural damage to the mouse gut microbiota caused by E. coli, and increased the abundance of beneficial bacteria, including Lachnospiraceae_NK4136_group. Additionally, RA lost its protective function against E. coli infection in a pseudosterile mouse model, suggesting that the protection induced by RA was dependent on the gut microbiota. In conclusion, these results indicate that RA alleviates E. coli-induced inflammatory damage to the intestinal barrier by inhibiting the NF-κB signalling pathway and maintaining gut microbiota homeostasis. These findings provide new ideas and foundations for the application of RA as protection against E. coli.

Role of microbiota in the GUT-SKIN AXIS responses to outdoor stressors

Beside the respiratory tract, the skin and the gut represent the first defensive lines of our body against the external insults displaying many important biochemical features able to maintain the epithelial barrier integrity and to regulate the tissue immune responses. The human microbiome is essential in maintaining the tissue homeostasis and its dysregulation may lead to tissue conditions including inflammatory pathologies. Among all external insults, air pollutants have been shown to cause oxidative stress damage within the target tissues via an OxInflammatory response. Dysregulation of the gut microbiome (dysbiosis) by outdoor stressors, including air pollutants, may promote the exacerbation of the skin tissue damage via the interplay between the gut-skin axis. The intent of this review is to highlight the ability of exogenous stressors to modulate the human gut-skin axis via a redox regulated mechanism affecting the microbiome and therefore contributing to the development and aggravation of gut and skin conditions.

Machine learning-assisted label-free colorectal cancer diagnosis using plasmonic needle-endoscopy system

Early and accurate detection of colorectal cancer (CRC) is critical for improving patient outcomes. Existing diagnostic techniques are often invasive and carry risks of complications. Herein, we introduce a plasmonic gold nanopolyhedron (AuNH)-coated needle-based surface-enhanced Raman scattering (SERS) sensor, integrated with endoscopy, for direct mucus sampling and label-free detection of CRC. The thin and flexible stainless-steel needle is coated with polymerized dopamine, which serves as an adhesive layer and simultaneously initiates the nucleation of gold nanoparticle (AuNP) seeds on the needle surface. The AuNP seeds are further grown through a surface-directed reduction using Au ions-hydroxylamine hydrochloride solution, resulting in the formation of dense AuNHs. The formation mechanism of AuNHs and the layered structure of the plasmonic needle-based SERS (PNS) sensor are thoroughly analyzed. Furthermore, a strong field enhancement of the PNS sensor is observed, amplified around the edges of the polyhedral shapes and at nanogap sites between AuNHs. The feasibility of the PNS sensor combined with endoscopy system is further investigated using mouse models for direct colonic mucus sampling and verifying noninvasive label-free classification of CRC from normal controls. A logistic regression-based machine learning method is employed and successfully differentiates CRC and normal mice, achieving 100% sensitivity, 93.33% specificity, and 96.67% accuracy. Moreover, Raman profiling of metabolites and their correlations with Raman signals of mucus samples are analyzed using the Pearson correlation coefficient, offering insights for identifying potential cancer biomarkers. The developed PNS-assisted endoscopy technology is expected to advance the early screening and diagnosis approach of CRC in the future.

Lactobacillus plantarum 69-2 combined with α-lactalbumin hydrolysate alleviates DSS-induced ulcerative colitis through the TLR4/NF-κB inflammatory pathway and the gut microbiota in mice

Ulcerative colitis (UC), an inflammatory bowel disease, seriously affects people's quality of life. Diet-derived active peptides and Lactobacillus plantarum have shown promise for mitigating symptoms of UC. This investigation explored the combined effects of α-lactalbumin (α-LA) hydrolysate, which boasts a high antioxidant capacity, and L. plantarum 69-2 (L69-2) on a colitis mouse model. The results showed that α-LA hydrolysate with a molecular weight <3 kDa obtained with neutral protease had excellent antioxidant activity and potential to enhance probiotic proliferation. Furthermore, the synergistic application of α-LA hydrolysate and L69-2 could alleviate the adverse impact of colon inflammation by reducing oxidative stress and regulating immune disorders. It maintains the intestinal epithelial barrier, thereby reducing immune system over-activation, promoting the colonization of beneficial bacteria, and regulating intestinal immune responses. Simultaneously, it remodels the structure of the disrupted intestinal flora. The increase in the richness and diversity of the flora leads to the production of beneficial metabolites, which in turn inhibits the activation of the TLR4/NF-κB inflammatory pathway. This study provides a novel perspective on milk-derived peptide synergism with probiotics in alleviating UC.

The Versatile Role of Peroxisome Proliferator-Activated Receptors in Immune-Mediated Intestinal Diseases

Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that sense lipophilic molecules and act as transcription factors to regulate target genes. PPARs have been implicated in the regulation of innate immunity, glucose and lipid metabolism, cell proliferation, wound healing, and fibrotic processes. Some synthetic PPAR ligands are promising molecules for the treatment of inflammatory and fibrotic processes in immune-mediated intestinal diseases. Some of these are currently undergoing or have previously undergone clinical trials. Dietary PPAR ligands and changes in microbiota composition could modulate PPARs' activation to reduce inflammatory responses in these immune-mediated diseases, based on animal models and clinical trials. This narrative review aims to summarize the role of PPARs in immune-mediated bowel diseases and their potential therapeutic use.

Multi-omics insights into anti-colitis benefits of the synbiotic and postbiotic derived from wheat bran arabinoxylan and Limosilactobacillus reuteri

Exploring nutritional therapies that manipulate tryptophan metabolism to activate AhR signaling represents a promising approach for mitigating chronic colitis. Arabinoxylan is a bioactive constituent abundant in wheat bran. Here, we comprehensively investigated anti-colitis potentials of wheat bran arabinoxylan (WBAX), its synbiotic and postbiotic derived from WBAX and Limosilactobacillus reuteri WX-94 (i.e., a probiotic strain exhibiting tryptophan metabolic activity). WBAX fueled L. reuteri and promoted microbial conversion of tryptophan to AhR ligands during in vitro fermentation in the culture medium and in the fecal microbiota from type 2 diabetes. The WBAX postbiotic outperformed WBAX and its synbiotic in augmenting efficacy of tryptophan in restoring DSS-disturbed serum immune markers, colonic tight junction proteins and gene profiles involved in amino acid metabolism and FoxO signaling. The WBAX postbiotic remodeled gut microbiota and superiorly enhanced AhR ligands (i.e., indole metabolites and bile acids), alongside with elevation in colonic AhR and IL-22. Associations between genera and metabolites modified by the postbiotic and colitis in human were verified and strong binding capacities between metabolites and colitis-related targets were demonstrated by molecular docking. Our study advances the novel perspective of WBAX in manipulating tryptophan metabolism and anti-colitis potentials of WBAX postbiotic via promoting gut microbiota-dependent AhR signaling.

Structural characteristics of a polysaccharide from Armillariella tabescens and its protective effect on colitis mice via regulating gut microbiota and intestinal barrier function

A new polysaccharide fraction (ATP) was obtained from Armillariella tabescens mycelium. Structural analysis suggested that the backbone of ATP was →4)-α-D-Glcp(1 → 2)-α-D-Galp(1 → 2)-α-D-Glcp(1 → 4)-α-D-Glcp(1→, which branched at O-3 of →2)-α-D-Glcp(1 → and terminated with T-α-D-Glcp or T-α-D-Manp. Besides, ATP significantly alleviated ulcerative colitis (UC) symptoms and inhibited the production of pro-inflammation cytokines (IL-1β, IL-6). Meanwhile, ATP could improve colon tissue damage by elevating the expression of MUC2 and tight junction proteins (ZO-1, occludin and claudin-1) levels and enhance intestinal barrier function through inhibiting the activation of MMP12/MLCK/p-MLC2 signaling pathway. Further studies exhibited that ATP could increase the relative abundance of beneficial bacteria such as f. Muribaculacese, g. Muribaculaceae, and g. Alistips, and decrease the relative abundance of g. Desulfovibrio, g. Colidextribacter, g. Ruminococcaceae and g.Oscillibacter, and regulate the level of short-chain fatty acids. Importantly, FMT intervention with ATP-derived microbiome certified that gut microbiota was involved in the protective effects of ATP on UC. The results indicated that ATP was potential to be further developed into promising therapeutic agent for UC.

Multi-omics integrated analyses indicated that non-polysaccharides of Sijunzi decoction ameliorated spleen deficiency syndrome via regulating microbiota-gut-metabolites axis and exerted synergistic compatibility

ETHNOPHARMACOLOGICAL RELEVANCE

As a classical traditional Chinese medicine formula to invigorating spleen and replenishing qi, Sijunzi decoction (SJZD) is composed of four herbs, which is applied to cure spleen deficiency syndrome (SDS) clinically. The non-polysaccharides (NPSs) of SJZD (SJZD_NPS) are important pharmacodynamic material basis. However, the amelioration mechanism of SJZD_NPS on SDS has not been fully elaborated. Additionally, the contribution of herbs compatibility to efficacy of this formula remains unclear.

AIM OF THE STUDY

The aim was to explore the underlying mechanisms of SJZD_NPS on improving SDS, and uncover the scientific connotation in SJZD compatibility.

MATERIALS AND METHODS

A strategy integrating incomplete formulae (called "Chai-fang" in Chinese) comparison, pharmacodynamics, gut microbiome, and metabolome was employed to reveal the role of each herb to SJZD compatibility against SDS. Additionally, the underlying mechanism harbored by SJZD_NPS was further explored through targeted metabolomics, network pharmacology, molecular docking, pseudo-sterile model, and metagenomics.

RESULTS

SJZD_NPS significantly alleviated diarrhea, disordered secretion of gastrointestinal hormones and neurotransmitters, damage of ileal morphology and intestinal barrier in SDS rats, which was superior to the NPSs of Chai-fang. 16S rRNA gene sequencing and metabolomics analyses revealed that SJZD_NPS effectively restored the disturbed gut microbiota community and abnormal metabolism caused by SDS, showing the most evident recovery. Moreover, SJZD_NPS recalled the levels of partial amino acids, short chain fatty acids and bile acids, which possessed strong binding affinity towards potential targets. The depletion of gut microbiota confirmed that the SDS-amelioration efficacy of SJZD_NPS is dependent on the intact gut microbiome, with the relative abundance of potential probiotics such as Lactobacillus_johnsonii and Lactobacillus_taiwanensis been enriched.

CONCLUSION

NPSs in SJZD can improve SDS-induced gastrointestinal-nervous system dysfunction through regulating microbiota-gut-metabolites axis, with four herbs exerting synergistic effects, which indicated the compatibility rationality of SJZD.

Rosemary (Rosmarinus officinalis L.) polyphenols and inflammatory bowel diseases: Major phytochemicals, functional properties, and health effects

Major polyphenols in Rosmarinus officinalis L. primarily consist of phenolic acids, phenolic diterpenes, and flavonoids, all of which have pharmacological properties including anti-inflammatory and antibacterial characteristics. Numerous in vitro and animal studies have found that rosemary polyphenols have the potential to decrease the severity of intestinal inflammation. The beneficial effects of rosemary polyphenols were associated with anti-inflammatory properties, including improved gut barrier (increased mucus secretion and tight junction), increased antioxidant enzymes, inhibiting inflammatory pathways and cytokines (downregulation of NF-κB, NLRP3 inflammasomes, STAT3 and activation of Nrf2), and modulating gut microbiota community (increased core probiotics and SCFA-producing bacteria, and decreased potential pathogens) and metabolism (changes in SCFA and bile acid metabolites). This paper provides a better understanding of the anti-inflammatory properties of rosemary polyphenols and suggests that rosemary polyphenols might be employed as strong anti-inflammatory agents to prevent intestinal inflammation and lower the risk of inflammatory bowel disease and related diseases.

Protective effect of 1,3-dioleoyl-2-palmitoylglycerol against DSS-induced colitis via modulating gut microbiota and maintaining intestinal epithelial barrier integrity

Inflammatory bowel disease (IBD) is a challenging condition to cure that can occur at any age. The gut microbiome and intestinal epithelial barrier play a crucial role in the development of IBD. 1,3-Dioleoyl-2-palmitoylglycerol (OPO), the predominant triglyceride in breast milk, is a structural lipid with multiple physiological functions. However, the protective effect of OPO on IBD and its underlying mechanism remains unclear. This study showed that oral administration of OPO markedly ameliorated dextran sulfate sodium (DSS)-induced colitis phenotypes. OPO treatment reduced inflammation levels by suppressing the TLR4-MyD88-NF-κB signaling pathway in colitis mice. Furthermore, OPO treatment improved intestinal epithelial barrier function via promoting epithelial cell proliferation and differentiation, inhibiting cell apoptosis, and upregulating tight junction protein expression. The 16S rRNA gene sequencing revealed that OPO treatment restored microbial alpha diversity and reshaped the microbiota of colitis mice. Therefore, our study revealed that OPO exhibited a protective role in DSS-induced colitis via maintaining intestinal epithelial barrier integrity and modulating gut microbiota. Our results highlight that OPO could be used as effective supplements for individuals with IBD or intestinal dysfunctions.

Combining Gut Microbiota Modulation and Enzymatic-Triggered Colonic Delivery by Prebiotic Nanoparticles Improves Mouse Colitis Therapy

The efficacy of ulcerative colitis (UC) therapy is closely connected to the composition of gut microbiota in the gastrointestinal tract. Prebiotic-based nanoparticles (NPs) provide a more precise approach to alleviate UC via modulating gut microbiota dysbiosis. The present study develops an efficient prebiotic-based colon-targeted drug delivery system (PCDDS) by using prebiotic pectin (Pcn) and chitosan (Csn) polysaccharides as a prebiotic shell, with the anti-inflammatory drug sulfasalazine (SAS) loaded into a poly(lactic-co-glycolic acid) (PLGA) core to construct SAS@PLGA-Csn-Pcn NPs. Then, we examine its characterization, cellular uptake, and in vivo therapeutic efficacy. The results of our study indicate that the Pcn/Csn shell confers efficient pH-sensitivity properties. The gut microbiota-secreted pectinase serves as the trigger agent for Pcn/Csn shell degradation, and the resulting Pcn oligosaccharides possess a substantial prebiotic property. Meanwhile, the formed PCDDSs exhibit robust biodistribution and accumulation in the colon tissue, rapid cellular uptake, efficient in vivo therapeutic efficacy, and modulation of gut microbiota dysbiosis in a mouse colitis model. Collectively, our synthetic PCDDSs demonstrate a promising and synergistic strategy for UC therapy.

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.

Astragalus polysaccharides-induced gut microbiota play a predominant role in enhancing of intestinal barrier function of broiler chickens

BACKGROUND

The intestinal barrier is the first line of defense against intestinal invasion by pathogens and foreign antigens and is closely associated with the gut microbiota. Astragalus polysaccharides (APS) have a long history of use in traditional Chinese medicine owing to its protective properties against intestinal barrier function. The mechanism of APS-induced gut microbiota enhancing intestinal barrier function is urgently needed.

RESULTS

Dietary polysaccharide deprivation induced intestinal barrier dysfunction, decreased growth performance, altered microbial composition (Faecalibacterium, Dorea, and Coprobacillus), and reduced isobutyrate concentration. The results showed that APS facilitates intestinal barrier function in broiler chickens, including a thicker mucus layer, reduced crypt depth, and the growth of tight junction proteins. We studied the landscape of APS-induced gut microbiota and found that APS selectively promoted the growth of Parabacteroides, a commensal bacterium that plays a predominant role in enhancing intestinal barrier function. An in vitro growth assay further verified that APS selectively increased the abundance of Parabacteroides distasonis and Bacteroides uniformis. Dietary APS supplementation increased the concentrations of isobutyrate and bile acid (mainly chenodeoxycholic acid and deoxycholate acid) and activated signaling pathways related to intestinal barrier function (such as protein processing in the endoplasmic reticulum, tight junctions, and adherens junction signaling pathways).

CONCLUSIONS

APS intervention restored the dietary polysaccharide-induced dysfunction of the intestinal barrier by selectively promoting the abundance of Parabacteroides distasonis, and increasing the concentrations of isobutyrate and bile acids (mainly CDCA and DCA). These findings suggest that APS-induced gut microbiota and metabolic niches are promising strategies for enhancing intestinal barrier function.

Rosmarinic acid alleviates fungal keratitis caused by Aspergillus fumigatus by inducing macrophage autophagy

Fungal keratitis (FK) is an infectious keratopathy can cause serious damage to vision. Its severity is related to the virulence of fungus and response of inflammatory. Rosmarinic acid (RA) extracted from Rosmarinus officinalis exhibits antioxidant, anti-inflammatory and anti-viral properties. The aim of this study was to investigate the effect of RA on macrophage autophagy and its therapeutic effect on FK. In this study, we demonstrated that RA reduced expression of proinflammatory cytokine, lessened the recruitment of inflammatory cells in FK. The relative contents of autophagy markers, such as LC3 and Beclin-1, were significantly up-regulated in RAW 264.7 cells and FK. In addition, RA restored mitochondrial membrane potential (MMP) of macrophage to normal level. RA not only reduced the production of intracellular reactive oxygen species (ROS) but also mitochondria ROS (mtROS) in macrophage. At the same time, RA induced macrophage to M2 phenotype and down-regulated the mRNA expression of IL-6, IL-1β, TNF-α. All the above effects could be offset by the autophagy inhibitor 3-Methyladenine (3-MA). Besides, RA promote phagocytosis of RAW 264.7 cells and inhibits spore germination, biofilm formation and conidial adherence, suggesting a potential therapeutic role for RA in FK.

Sialylation of dietary mucin modulate its digestibility and the gut microbiota of elderly individuals

Food-derived mucins are glycoproteins rich in sialic acid, but their digestive properties and potential health benefits for humans have been scarcely investigated. In this work, ovomucin (OVM, rich in N-acetylneuraminic acid, about 3 %), porcine small intestinal mucin (PSIM, rich in N-glycolylneuraminic acid, about 1 %), the desialylated OVM (AOVM) and the desialylated PSIM (APSIM) were selected to examine their digestion and their impact on the gut microbiota of elderly individuals. The results shown that, the proportion of low-molecular-weight proteins increased after simulated digestion of these four mucins, with concomitant comparable antioxidant activity observed. Desialylation markedly increased the degradation and digestion rate of mucins. In vitro fecal fermentation was conducted with these mucins using fecal samples from individuals of different age groups: young, low-age and high-age elderly. Fecal fermentation with mucin digestive solution stimulated the production of organic acids in the group with fecal sample of the elderly individuals. Among them, the OVM group demonstrated the most favorable outcomes. The OVM and APSIM groups elevated the relative abundance of beneficial bacteria such as Lactobacillus and Bifidobacterium, while diminishing the presence of pathogenic bacteria such as Klebsiella. Conversely, the probiotic effects of AOVM and PSIM were attenuated or even exhibited adverse effects. Hence, mucins originating from different sources and possessing distinct glycosylation patterns exhibit diverse biological functions. Our findings can offer valuable insights for developing a well-balanced and nutritious diet tailored to the elderly population.

Lacticaseibacillus paracasei JS-3 Isolated from "Jiangshui" Ameliorates Hyperuricemia by Regulating Gut Microbiota and iTS Metabolism

Background: A diet high in purines can impair the function of the gut microbiota and disrupt purine metabolism, which is closely associated with the onset of hyperuricemia. Dietary regulation and intestinal health maintenance are key approaches for controlling uric acid (UA) levels. Investigating the impacts of fermented foods offers potential dietary interventions for managing hyperuricemia. Methods: In this study, we isolated a strain with potent UA-degrading capabilities from "Jiangshui", a fermented food product from Gansu, China. We performed strain identification and assessed its probiotic potential. Hyperuricemic quails, induced by a high-purine diet, were used to assess the UA degradation capability of strain JS-3 by measuring UA levels in serum and feces. Additionally, the UA degradation pathways were elucidated through analyses of the gut microbiome and fecal metabolomics. Results: JS-3, identified as Lacticaseibacillus paracasei, was capable of eliminating 16.11% of uric acid (UA) within 72 h, rapidly proliferating and producing acid within 12 h, and surviving in the gastrointestinal tract. Using hyperuricemic quail models, we assessed JS-3's UA degradation capacity. Two weeks after the administration of JS-3 (2 × 108 cfu/d per quail), serum uric acid (SUA) levels significantly decreased to normal levels, and renal damage in quails was markedly improved. Concurrently, feces from the JS-3 group demonstrated a significant degradation of UA, achieving up to 49% within 24 h. 16S rRNA sequencing revealed JS-3's role in gut microbiota restoration by augmenting the probiotic community (Bifidobacterium, Bacteroides unclassified_f-Lachnospiraceae, and norank_fynorank_o-Clostridia_UCG-014) and diminishing the pathogenic bacteria (Macrococus and Lactococcus). Corresponding with the rise in short-chain fatty acid (SCFA)-producing bacteria, JS-3 significantly increased SCFA levels (p < 0.05, 0.01). Additionally, JS-3 ameliorated metabolic disturbances in hyperuricemic quails, influencing 26 abnormal metabolites predominantly linked to purine, tryptophan, and bile acid metabolism, thereby enhancing UA degradation and renal protection. Conclusions: For the first time, we isolated and identified an active probiotic strain, JS-3, from the "Jiangshui" in Gansu, used for the treatment of hyperuricemia. It modulates host-microbiome interactions, impacts the metabolome, enhances intestinal UA degradation, reduces levels of SUA and fecal UA, alleviates renal damage, and effectively treats hyperuricemia without causing gastrointestinal damage. In summary, JS-3 can serve as a probiotic with potential therapeutic value for the treatment of hyperuricemia.

Effects of dietary chlorogenic acid on cecal microbiota and metabolites in broilers during lipopolysaccharide-induced immune stress

Aims

The aim of this study was to investigate the effects of chlorogenic acid (CGA) on the intestinal microorganisms and metabolites in broilers during lipopolysaccharide (LPS)-induced immune stress.

Methods

A total of 312 one-day-old Arbor Acres (AA) broilers were randomly allocated to four groups with six replicates per group and 13 broilers per replicate: (1) MS group (injected with saline and fed the basal diet); (2) ML group (injected with 0.5 mg LPS/kg and fed the basal diet); (3) MA group (injected with 0.5 mg LPS/kg and fed the basal diet supplemented with 1,000 mg/kg CGA); and (4) MB group (injected with saline and fed the basal diet supplemented with 1,000 mg/kg CGA).

Results

The results showed that the abundance of beneficial bacteria such as Bacteroidetes in the MB group was significantly higher than that in MS group, while the abundance of pathogenic bacteria such as Streptococcaceae was significantly decreased in the MB group. The addition of CGA significantly inhibited the increase of the abundance of harmful bacteria such as Streptococcaceae, Proteobacteria and Pseudomonas caused by LPS stress. The population of butyric acid-producing bacteria such as Lachnospiraceae and Coprococcus and beneficial bacteria such as Coriobacteriaceae in the MA group increased significantly. Non-targeted metabonomic analysis showed that LPS stress significantly upregulated the 12-keto-tetrahydroleukotriene B4, riboflavin and mannitol. Indole-3-acetate, xanthurenic acid, L-formylkynurenine, pyrrole-2-carboxylic acid and L-glutamic acid were significantly down-regulated, indicating that LPS activated inflammation and oxidation in broilers, resulting in intestinal barrier damage. The addition of CGA to the diet of LPS-stimulated broilers significantly decreased 12-keto-tetrahydro-leukotriene B4 and leukotriene F4 in arachidonic acid metabolism and riboflavin and mannitol in ABC transporters, and significantly increased N-acetyl-L-glutamate 5-semialdehyde in the biosynthesis of amino acids and arginine, The presence of pyrrole-2-carboxylic acid in D-amino acid metabolism and the cecal metabolites, indolelactic acid, xanthurenic acid and L-kynurenine, indicated that CGA could reduce the inflammatory response induced by immune stress, enhance intestinal barrier function, and boost antioxidant capacity.

Conclusion

We conclude that CGA can have a beneficial effect on broilers by positively altering the balance of intestinal microorganisms and their metabolites to inhibit intestinal inflammation and barrier damage caused by immune stress.

Bifidobacterium breve Protects the Intestinal Epithelium and Mitigates Inflammation in Colitis via Regulating the Gut Microbiota-Cholic Acid Pathway

In this study, we aimed to explore the protective effects of Bifidobacterium in colitis mice and the potential mechanisms. Results showed that Bifidobacterium breve (B. breve) effectively colonized the intestinal tract and alleviated colitis symptoms by reducing the disease activity index. Moreover, B. breve mitigated intestinal epithelial cell damage, inhibited the pro-inflammatory factors, and upregulated tight junction (TJ)-proteins. Gut microbiota and metabolome analysis found that B. breve boosted bile acid-regulating genera (such as Bifidobacterium and Clostridium sensu stricto 1), which promoted bile acid deconjugation in the intestine. Notably, cholic acid (CA) was closely associated with the expression levels of inflammatory factors and TJ-proteins (p < 0.05). Our in vitro cell experiments further confirmed that CA (20.24 ± 4.53 pg/mL) contributed to the inhibition of lipopolysaccharide-induced tumor necrosis factor-α expression (49.32 ± 5.27 pg/mL) and enhanced the expression of TJ-proteins (Occludin and Claudin-1) and MUC2. This study suggested that B. breve could be a probiotic candidate for use in infant foods.

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.

Effects of dietary traditional Chinese medicine residues on growth performance, intestinal health and gut microbiota compositions in weaned piglets

Weaning stress can induce diarrhea, intestinal damage and flora disorder of piglets, leading to slow growth and even death of piglets. Traditional Chinese medicine residue contains a variety of active ingredients and nutrients, and its resource utilization has always been a headache. Therefore, we aimed to investigate the effects of traditional Chinese medicine residues (Xiasangju, composed of prunellae spica, mulberry leaves, and chrysanthemum indici flos) on growth performance, diarrhea, immune function, and intestinal health in weaned piglets. Forty-eight healthy Duroc× Landrace × Yorkshire castrated males weaned aged 21 days with similar body conditions were randomly divided into 6 groups with eight replicates of one piglet. The control group was fed a basal diet, the antibiotic control group was supplemented with 75 mg/kg chlortetracycline, and the residue treatment groups were supplemented with 0.5%, 1.0%, 2.0% and 4.0% Xiasangju residues. The results showed that dietary Xiasangju residues significantly reduced the average daily feed intake, but reduced the diarrhea score (P < 0.05). The 1.0% and 2.0% Xiasangju residues significantly increased the serum IgM content of piglets, and the 0.5%, 1.0%, 2.0% and 4.0% Xiasangju residues significantly increased the serum IgG content, while the 1.0%, 2.0% and 4.0% Xiasangju residues significantly increased the sIgA content of ileal contents (P < 0.05). Dietary Xiasangju residues significantly increased the villus height and the number of villus goblet cells in the jejunum and ileum, and significantly decreased the crypt depth (P<0.05). The relative mRNA expression of IL-10 in the ileum was significantly increased in the 1% and 2% Xiasangju residues supplemented groups (P < 0.05), while IL-1β in the ileum was downregulated (P < 0.05). Xiasangju residues improved the gut tight barrier, as evidenced by the enhanced expression of Occludin and ZO-1 in the jejunum and ileum. The diets with 1% Xiasangju residues significantly increased the relative abundance of Lactobacillus johnsonii, and 2% and 4% Xiasangju residues significantly increased the relative abundance of Weissella jogaeotgali (P < 0.05). Dietary supplementation with 0.5%, 1.0%, 2% and 4% with Xiasangju residues significantly decreased the relative abundance of Escherichia coli and Treponema porcinum (P < 0.05). In summary, dietary supplementation with Xiasangju residues improves intestinal health and gut microbiota in weaned piglets.

Detrimental Impacts of Pharmaceutical Excipient PEG400 on Gut Microbiota and Metabolome in Healthy Mice

Polyethylene glycol 400 (PEG400) is a widely used pharmaceutical excipient in the field of medicine. It not only enhances the dispersion stability of the main drug but also facilitates the absorption of multiple drugs. Our previous study found that the long-term application of PEG400 as an adjuvant in traditional Chinese medicine preparations resulted in wasting and weight loss in animals, which aroused our concern. In this study, 16S rRNA high-throughput sequencing technology was used to analyze the diversity of gut microbiota, and LC-MS/MS Q-Exactive Orbtriap metabolomics technology was used to analyze the effect of PEG400 on the metabolome of healthy mice, combined with intestinal pathological analysis, aiming to investigate the effects of PEG400 on healthy mice. These results showed that PEG400 significantly altered the structure of gut microbiota, reduced the richness and diversity of intestinal flora, greatly increased the abundance of Akkermansia muciniphila (A. muciniphila), increased the proportion of Bacteroidetes to Firmicutes, and reduced the abundance of many beneficial bacteria. Moreover, PEG400 changed the characteristics of fecal metabolome in mice and induced disorders in lipid and energy metabolism, thus leading to diarrhea, weight loss, and intestinal inflammation in mice. Collectively, these findings provide new evidence for the potential effect of PEG400 ingestion on a healthy host.