Homeostasis and inflammation in the intestine

Maternal lead exposure impairs offspring growth and intestinal microbiota via AMPK/ULK1 pathway activation

The pervasive presence and bioaccumulation of lead (Pb2 +) in living organisms pose a significant risk to human health. Extensive research has been conducted on the neurotoxicity and reproductive toxicity of lead, but the impact of maternal lead exposure on subsequent generations still needs to be addressed. Therefore, we aimed to explore the adverse effects and mechanisms of lead exposure in pregnant mice on the next generation. The present study indicated that lead exposure decreased growth performance and impaired the function of the colon, spleen, testes, and kidneys in the next generation of mice. Furthermore, we found that lead exposure activated autophagy by regulating the AMPK/ULK1 pathway and reduced the relative expression levels of tight junction proteins in a dose-dependent manner. Moreover, the composition of the gut microbiota showed significant alterations compared to the control group. These changes were characterized by a marked reduction in the relative abundance of beneficial bacteria, including Variovorax, Harryflintia, and Romboutsi, while the abundance of pathogenic bacteria such as Mucispirillum and Klebsiella was significantly increased. Such shifts in microbial composition indicated a disruption in microbial homeostasis, contributing to health impairments. In summary, our study indicated that lead exposure in pregnant mice not only decreased the growth performance and impaired multiple organs in the next generation of mice but also disrupted gut microbial homeostasis and induced autophagy via activating the AMPK/ULK1 pathway, resulting in adverse health outcomes in offspring. Additionally, the current study provides a solid experimental foundation for environmental agencies worldwide to implement effective strategies to mitigate lead contamination.

A randomised trial of pleuran in paediatric acute gastroenteritis

Pleuran, as a potent immunomodulator targeting intestinal immunity with a strong safety profile, could be a potential treatment for acute gastroenteritis. This study evaluates the effect of pleuran on the duration and severity of acute infectious diarrhoea in children. This is a multi-centre, randomised, double-blind, placebo-controlled, CONSORT statement superiority trial. Children aged 2-10 years presenting to hospital with acute gastroenteritis were included. The primary outcome measure was the duration of diarrhoea. Twenty-seven children were enrolled. There were no significant differences between the experimental and control groups regarding duration of diarrhoea, hospitalisation, intravenous rehydration and symptom severity. The administration of Pleuran was well tolerated. In this study, Pleuran was ineffective in the treatment of acute gastroenteritis in children. Further studies are needed to investigate its potential as a nutraceutical in children.Clinical registration: ClinicalTrials.gov ID: NCT03988257 (the date of registration: 17/06/2019). The Medical University of Warsaw Bioethical Committee Approval: KB/45/2018. Nutricia Foundation Grant: RG-3/2018.

Interaction between Infection of Porphyromonas gingivalis, A Keystone Microbe of Oral Microbiome, and Serum Levels of Lutein/Zeaxanthin Is Associated with Risk for Age-related Macular Degeneration

Porphyromonas gingivalis (P. gingivalis) functions as a catalyst bacterium in the development of periodontitis, and the serum antibody level against P. gingivalis is considered a surrogate marker for the activity level of periodontopathic microbiome. The chronic systemic inflammation induced by P. gingivalis elevates the risk of various systemic and neurodegenerative disorders, including atherosclerosis, diabetes, and Alzheimer's disease. Although the connection between human microbiome and age-related macular degeneration (AMD) remains relatively unexplored, it is noteworthy that AMD shares risk factors and etiological mechanisms with diseases related to P. gingivalis. To investigate the potential association between periodontopathic microbiome and AMD occurrence, we conducted a candidate microbe approach case-control study. Our hypothesis was tested by examining the correlation between serum P. gingivalis immunoglobulin G (IgG) levels and AMD. Comparing the lowest IgG category (≤ 57 enzyme-linked immunosorbent assay units (EU)) with higher categories revealed escalating risks: the second higher category (58-65 EU) conferred almost a 30% increased risk (odds ratio (OR) = 1.28, 95% confidence interval (CI): 1.17 to 1.4), the third higher category (66-119 EU) conferred nearly a 60% increase (OR = 1.58, 95% CI: 1.46 to 1.72), and the highest category (> 119 EU) conveyed over a two-fold risk (OR = 2.04, 95% CI: 1.62 to 2.58) of early AMD. Aligning with the notion that the microbiome composition is significantly shaped by the host's diet, our analysis indicates that sustaining elevated serum levels of lutein/zeaxanthin (≥ 0.35 μmol/L or ≥ 20 μg/dL) might potentially mitigate the P. gingivalis-related AMD risk by as much as 35% (P for interaction < 0.0001). Although the precise mechanism requires additional exploration, these findings suggest a connection between nutrition and oral microbiome, emphasizing their collective role in maintaining eye health.

SIGNIFICANCE STATEMENT

While our oral microbiome may impact eye health, nutritional factors could play a modulatory role in mitigating the associated risk.

Gut Microbiota Modulation in IBD: From the Old Paradigm to Revolutionary Tools

Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders primarily comprising two main conditions: ulcerative colitis and Crohn's disease. The gut microbiota's role in driving inflammation in IBD has garnered significant attention, yet the precise mechanisms through which the microbiota influences IBD pathogenesis remain largely unclear. Given the limited therapeutic options for IBD, alternative microbiota-targeted therapies-including prebiotics, probiotics, postbiotics, and symbiotics-have been proposed. While these approaches have shown promising results, microbiota modulation is still mainly considered an adjunct therapy to conventional treatments, with a demonstrated impact on patients' quality of life. Fecal microbiota transplantation (FMT), already approved for treating Clostridioides difficile infection, represents the first in a series of innovative microbiota-based therapies under investigation. Microbial biotherapeutics are emerging as personalized and cutting-edge tools for IBD management, encompassing next-generation probiotics, bacterial consortia, bacteriophages, engineered probiotics, direct metabolic pathway modulation, and nanotherapeutics. This review explores microbial modulation as a therapeutic strategy for IBDs, highlighting current approaches and examining promising tools under development to better understand their potential clinical applications in managing intestinal inflammatory disorders.

The Intestinal Macrophage-Intestinal Stem Cell Axis in Inflammatory Bowel Diseases: From Pathogenesis to Therapy

The gut plays a crucial role in digestion and immunity, so its balance is essential to overall health. This balance relies on dynamic interactions between intestinal epithelial cells, immune cells, and crypt stem cells. Inflammatory bowel disease (IBD), which consists of ulcerative colitis and Crohn's disease, is a chronic relapsing inflammatory disease of the gastrointestinal tract closely related to immune dysfunction. Stem cells, known for their ability to self-renew and differentiate, play an important role in repairing damaged intestinal epithelium and maintaining homeostasis in vivo. Macrophages are key gatekeepers of intestinal immune homeostasis and have a significant impact on IBD. Current research has focused on the link between epithelial cells and stem cells, but interactions with macrophages, which have been recognized as attractive targets for the development of new therapeutic approaches to disease, have been less explored. Recently, the developing field of immunometabolism has reinforced that metabolic reprogramming is a key determinant of macrophage function and subsequent disease progression. The aim of this review is to explore the role of the macrophage-stem cell axis in the maintenance of intestinal homeostasis and to summarize potential approaches to treating IBD by manipulating the cellular metabolism of macrophages, as well as the main opportunities and challenges faced. In summary, our overview provides a framework for understanding the critical role of macrophage immunometabolism in maintaining gut health and potential therapeutic targets.

Comparative analysis of gut microbiota in healthy and diarrheic foals

Diarrhea presents a substantial risk of high morbidity and mortality among foals. Although studies have shown connections between gut microbiota and several gastrointestinal diseases, there is still inadequate information on gut microbial alterations in foals during diarrhea. In this study, we conducted 16S rRNA and ITS gene amplicon sequencing to investigate gut bacterial and fungal differences between healthy and diarrheic foals. The results unveiled significant reductions in gut bacterial and fungal diversities among foals experiencing diarrhea, accompanied by notable shifts in the composition of gut microbial communities. A considerable decrease was observed in the relative abundance of 30 bacterial and 34 fungal genera. Moreover, two bacterial and eight fungal genera were utterly undetectable in the gut microbiota of diarrheic foals. Some decreased genera, such as Bifidobacterium and Saccharomyces, were deemed beneficial and recognized as probiotics. The study revealed significant alterations in foals' gut bacterial and fungal communities during diarrhea, which enriched our comprehension of gut microbial dynamics in foals across varying health statuses. These findings offer valuable insights for managing diarrhea through gut microbiota modulation, suggesting that probiotics may be superior to antibiotics in preventing and controlling foal diarrhea.IMPORTANCEThis research advances the understanding of gut bacterial and fungal dynamics in foals, highlighting gut microbiota dysbiosis as a potential contributor to foal diarrhea. Additionally, we observed that many altered bacteria and fungi were downregulated during diarrhea, including some probiotic strains. Consequently, our findings provide evidence that probiotics may offer superior efficacy compared with antibiotics as potential candidates for preventing and treating foal diarrhea.

Antibiotics and Opportunities of Their Alternatives in Pig Production: Mechanisms Through Modulating Intestinal Microbiota on Intestinal Health and Growth

Antibiotics at subtherapeutic levels have been used in pig diets as antimicrobial growth promoters. However, concerns about antibiotic resistance have increased the demand for alternatives to these antimicrobial growth promoters. This review paper explores the mechanisms through which antimicrobial growth promoters and their alternatives exert their antimicrobial effects. Additionally, this systemic review also covers how modulation of intestinal microbiota by antimicrobial growth promoters or their alternatives affects intestinal health and, subsequently, growth of pigs. The mechanisms and effects of antimicrobial growth promoters and their alternatives on intestinal microbiota, intestinal health, and growth are diverse and inconsistent. Therefore, pig producers should carefully assess which alternative is the most effective for optimizing both profitability and the health status of pigs in their production system.

The Microbiota and Evolution of Obesity

Obesity is a major global concern and is generally attributed to a combination of genetic and environmental factors. Several hypotheses have been proposed to explain the evolutionary origins of obesity epidemic, including thrifty and drifty genotypes, and changes in thermogenesis. Here, we put forward the hypothesis of metaflammation, which proposes that due to intense selection pressures exerted by environmental pathogens, specific genes that help develop a robust defense mechanism against infectious diseases have had evolutionary advantages and that this may contribute to obesity in modern times due to connections between the immune and energy storage systems. Indeed, incorporating the genetic variations of gut microbiota into the complex genetic framework of obesity makes it more polygenic than previously believed. Thus, uncovering the evolutionary origins of obesity requires a multifaceted approach that considers the complexity of human history, the unique genetic makeup of different populations, and the influence of gut microbiome on host genetics.

BT1549 coordinates the in vitro IL-10 inducing activity of Bacteroides thetaiotaomicron

The intestine is home to a complex immune system that is engaged in mutualistic interactions with the microbiome that maintain intestinal homeostasis. A variety of immune-derived anti-inflammatory mediators have been uncovered and shown to be critical for maintaining these beneficial immune-microbiome relationships. Notably, the gut microbiome actively invokes the induction of anti-inflammatory pathways that limit the development of microbiome-targeted inflammatory immune responses. Despite the importance of this microbiome-driven immunomodulation, detailed knowledge of the microbial factors that promote these responses remains limited. We have previously established that the gut symbiont Bacteroides thetaiotaomicron stimulates the production of the anti-inflammatory cytokine IL-10 via soluble factors in a Toll-like receptor 2 (TLR2)-MyD88-dependent manner. Here, using TLR2 activity reporter cell lines, we show that the capacity of B. thetaiotaomicron to stimulate TLR2 activity was not critically dependent on either of the canonical heterodimeric forms of TLR2, TLR2/TLR1, or TLR2/TLR6, that typically mediate its function. Furthermore, biochemical manipulation of B. thetaiotaomicron-conditioned media suggests that IL-10 induction is mediated by a protease-resistant or non-proteogenic factor. We next uncovered that deletion of gene BT1549, a predicted secreted lipoprotein, significantly impaired the capacity of B. thetaiotaomicron to induce IL-10, while complementation in trans restored IL-10 induction, suggesting a role for BT1549 in the immunomodulatory function of B. thetaiotaomicron. Collectively, these data provide molecular insight into the pathways through which B. thetaiotaomicron operates to promote intestinal immune tolerance and symbiosis.

IMPORTANCE

Intestinal homeostasis requires the establishment of peaceful interactions between the gut microbiome and the intestinal immune system. Members of the gut microbiome, like the symbiont Bacteroides thetaiotaomicron, actively induce anti-inflammatory immune responses to maintain mutualistic relationships with the host. Despite the importance of such interactions, the specific microbial factors responsible remain largely unknown. Here, we show that B. thetaiotaomicron, which stimulates Toll-like receptor 2 (TLR2) to drive IL-10 production, can stimulate TLR2 independently of TLR1 or TLR6, the two known TLR that can form heterodimers with TLR2 to mediate TLR2-dependent responses. Furthermore, we show that IL-10 induction is likely mediated by a protease-resistant or non-proteogenic factor, and that this requires gene BT1549, a predicted secreted lipoprotein and peptidase. Collectively, our work provides insight into the molecular dialog through which B. thetaiotaomicron coordinates anti-inflammatory immune responses. This knowledge may facilitate future strategies to promote such responses for therapeutic purposes.

Cimifugin improves intestinal barrier dysfunction by upregulating SIRT1 to regulate the NRF2/HO-1 signaling pathway

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal dysfunction. Cimifugin is an active component of Radix saposhnikoviae which is effective for maintaining intestinal barrier integrity and intestinal function. This study aimed to investigate the treatment efficacy of Cimifugin on intestinal barrier dysfunction and to unveil the relevant mechanism through network pharmacology and experimental verification as well as molecular docking. Through SuperPred and Pubchem databases, the targets of Cimifugin were obtained. The disease targets were screened using Disgenet and GEO databases. With STRING database and Cytoscape software, the analysis of PPI network was performed. In DAVID database, the hub genes of Cimifugin were analyzed using GO and Pathway enrichment analyses. To validate the binding of Cimifugin with core targets, molecular docking was performed. The in vitro cellular model of intestinal barrier was established via the induction of Caco2 cells with LPS. TEER was used to detect epithelial barrier function and permeability was measured using FITC-dextran (FD4). Western blotting was used to measure the expressions of SIRT1, tight junction proteins, and NRF2/HO-1 signaling pathway-related proteins. The fluorescence intensity of ZO-1, Occludin, and Claudin-1 was detected using immunofluorescence staining. ELISA was used to detect the expression levels of inflammatory cytokines. Through the integration of all targets of IBS and Cimifugin, 94 frequent drug-disease-related targets were identified. These targets were enriched in some signaling pathways, like cellular responses to stress, cellular responses to stimuli, and VEGFA-VEGFR2. Ten hub genes including PTGS2, ANPRP, TGFB1, ACACA, SIRT1, NEF2L2, APEX1, IL6, AKT1, and HSP90AB1 were obtained. Cimifugin showed strong affinity with four key genes, including AKT1, SIRT1, IL6, and NFE2L2 (NRF2), which were obtained through the intersection of hug genes with cellular responses to stimuli. In vitro experiments showed that Cimifugin ameliorated LPS-induced intestinal barrier injury in Caco2 cells via upregulating SIRT1 to modulate NRF2/HO-1 signaling pathway. Cimifugin could alleviate intestinal barrier dysfunction in IBS by upregulating SIRT1 to regulate the NRF2/HO-1 signaling pathway.

Lactobacillus acidophilus TW01 Mitigates PM2.5-Induced Lung Injury and Improves Gut Health in Mice

Background/Objectives: Exposure to fine particulate matter (PM2.5) causes significant respiratory and gastrointestinal health problems. In our prior research, we identified Lactobacillus acidophilus TW01 as a promising strain for mitigating oxidative damage, enhancing wound healing in intestinal epithelial cells, and protecting bronchial cells from cigarette smoke extract. Building upon these findings, this study examines the protective effects of this strain on lung damage induced by particulate matter (PM) through the gut-lung axis in mouse models. Methods: This study evaluated the protective effects of L. acidophilus TW01 against PM2.5-induced lung injury using two in vivo mouse models (OVA sensitization combined with PM2.5 exposure and DSS-induced colitis). Results: L. acidophilus TW01 exhibited significant protective effects in two in-vivo models, reducing pro-inflammatory cytokines (TNF-α, IL-6, and IL-5), modulating the immune response (IgG subtypes), and improving gut barrier integrity. Importantly, L. acidophilus TW01 increased the abundance of beneficial gut bacteria (Bifidobacterium and Lactobacillus). Conclusions: These findings highlight the significant protective/therapeutic potential of L. acidophilus TW01 in mitigating the adverse health effects of PM2.5 exposure, emphasizing the interplay between the gut and lung microbiomes in overall health. The multi-faceted protective effects of this probiotic suggest a novel, multi-pronged therapeutic strategy for addressing the widespread health consequences of air pollution.

Explore Alteration of Lung and Gut Microbiota in a Murine Model of OVA-Induced Asthma Treated by CpG Oligodeoxynucleotides

Aim

We sought to investigate the impact of CpG oligodeoxynucleotides (CpG-ODN) administration on the lung and gut microbiota in asthmatic mice, specifically focusing on changes in composition, diversity, and abundance, and to elucidate the microbial mechanisms underlying the therapeutic effects of CpG-ODN and identify potential beneficial bacteria indicative of its efficacy.

Methods

HE staining were used to analyze inflammation in lung, colon and small intestine tissues. High-throughput sequencing technology targeting 16S rRNA was employed to analyze the composition, diversity, and correlation of microbiome in the lung, colon and small intestine of control, model and CpG-ODN administration groups.

Results

(1) Histopathologically, both lung and intestinal tissue in asthmatic mice exhibited significant structural damage and inflammatory response, whereas the structure of both lung and intestinal tissue approached normal levels, accompanied by a notable improvement in the inflammatory response after CpG-ODN treatment. (2) In the specific microbiota composition analysis, bacterial dysbiosis observed in the asthmatic mice, accompanied by enrichment of Proteobacteria found to cause lung and intestinal epithelial damage and inflammatory reaction. After CpG-ODN administration, bacterial dysbiosis was improved, and a notable enrichment of beneficial bacteria, indicating a novel microecology. Meanwhile Oscillospira and Clostridium were identified as two biomarkers of the CpG-ODN treatment. (3) Heatmap analysis revealed significant correlations among lung, small intestine, and colon microbiota.

Conclusion

CpG-ODN treatment can ameliorate OVA-induced asthma in mice. One side, preserving the structural integrity of the lung and intestine, safeguarding the mucosal physical barrier, the other side, improving the dysbiosis of lung and gut microbiota in asthmatic mice. Beneficial bacteria and metabolites take up microecological advantages, regulate immune cells and participate in the mucosal immune response to protect the immune barrier. Meanwhile, Oscillospira and Clostridium as biomarkers for CpG-ODN treatment, has reference significance for exploring precise Fecal microbiota transplantation treatment for asthma.

Butyrolactone-I from Marine Fungal Metabolites Mitigates Heat-Stress-Induced Apoptosis in IPEC-J2 Cells and Mice Through the ROS/PERK/CHOP Signaling Pathway

Heat stress poses a significant challenge to animal husbandry, contributing to oxidative stress, intestinal mucosal injury, and apoptosis, which severely impact animal health, growth, and production efficiency. The development of safe, sustainable, and naturally derived solutions to mitigate these effects is critical for advancing sustainable agricultural practices. Butyrolactone-I (BTL-I), a bioactive compound derived from deep-sea fungi (Aspergillus), shows promise as a functional feed additive to combat heat stress in animals. This study explored the protective effects of BTL-I against heat-stress-induced oxidative stress and apoptosis in IPEC-J2 cells and mice. Our findings demonstrated that BTL-I effectively inhibited the heat-stress-induced upregulation of HSP70 and HSP90, alleviating intestinal heat stress. Both in vitro and in vivo experiments revealed that heat stress increased intestinal cell apoptosis, with a significant upregulation of Bax/Bcl-2 expression, while BTL-I pretreatment significantly reduced apoptosis-related protein levels, showcasing its protective effects. Furthermore, BTL-I suppressed oxidative stress markers (ROS and MDA) while enhancing antioxidant activity (SOD levels). BTL-I also reduced the expression of p-PERK, p-eIF2α, ATF4, and CHOP, mitigating oxidative and endoplasmic reticulum stress in intestinal cells. In conclusion, BTL-I demonstrates the potential to improve animal resilience to heat stress, supporting sustainable livestock production systems. Its application as a natural, eco-friendly feed additive will contribute to the development of sustainable agricultural practices.

Deriving Human Intestinal Organoids with Functional Tissue-Resident Macrophages All From Pluripotent Stem Cells

BACKGROUND & AIMS

Organs of the gastrointestinal tract contain tissue-resident immune cells that function during tissue development, homeostasis, and disease. However, most published human organoid model systems lack resident immune cells, thus limiting their potential as disease avatars. For example, human intestinal organoids (HIOs) derived from pluripotent stem cells contain epithelial and various mesenchymal cell types but lack immune cells. In this study, we aimed to develop an HIO model with functional tissue-resident macrophages.

METHODS

HIOs and macrophages were generated separately through the directed differentiation of human pluripotent stem cells and combined in vitro. Following 2 weeks of coculture, the organoids were used for transcriptional profiling, functional analysis of macrophages, or transplanted into immunocompromised mice and matured in vivo for an additional 10-12 weeks.

RESULTS

Macrophages were incorporated into developing HIOs and persisted for 2 weeks in vitro HIOs and for at least 12 weeks in HIOs in vivo. These cocultured macrophages had a transcriptional signature that resembled those in the human fetal intestine, indicating that they were acquiring the features of tissue-resident macrophages. HIO macrophages could phagocytose bacteria and produced inflammatory cytokines in response to proinflammatory signals, such as lipopolysaccharide, which could be reversed with interleukin-10.

CONCLUSIONS

We generated an HIO system containing functional tissue-resident macrophages for an extended period. This new organoid system can be used to investigate the molecular mechanisms involved in inflammatory bowel disease.

Controlling functional homeostasis of ileal resident macrophages by vitamin B12 during steady state and Salmonella infection in mice

Dietary micronutrients, particularly vitamin B12 (VB12), profoundly influence the physiological maintenance and function of intestinal cells. However, it is still unclear whether VB12 modulates the transcriptional and metabolic programming of ileal macrophages (iMacs), thereby contributing to intestinal homeostasis. Using multiomic approaches, we demonstrated that VB12 primarily supports the cell cycle activity and mitochondrial metabolism of iMacs, resulting in increased cell frequency compared to VB12 deficiency. VB12 also retained the ability to promote maintenance and metabolic regulation of iMacs during intestinal infection with Salmonella Typhimurium (STm). On the contrary, depletion of iMacs by inhibiting CSF1R signaling significantly increased host susceptibility to STm and prevented VB12-mediated pathogen reduction. These results thus suggest that regulation of VB12-dependent iMacs critically controls STm expansion, which may be of new relevance to advance our understanding of this vitamin and to strategically formulate sustainable therapeutic nutritional regimens that improve human gut health.

Identification of Key Genes in Fetal Gut Development at Single-Cell Level by Exploiting Machine Learning Techniques

The study of fetal gut development is critical due to its substantial influence on immediate neonatal and long-term adult health. Current research largely focuses on microbiome colonization, gut immunity, and barrier function, alongside the impact of external factors on these phenomena. Limited research has been dedicated to the categorization of developing fetal gut cells. Our study aimed to enhance our understanding of fetal gut development by employing advanced machine-learning techniques on single-cell sequencing data. This dataset consisted of 62,849 samples, each characterized by 33,694 distinct gene features. Four feature ranking algorithms were utilized to sort features according to their significance, resulting in four feature lists. Then, these lists were fed into an incremental feature selection method to extract essential genes, classification rules, and build efficient classifiers. Several important genes were recognized by multiple feature ranking algorithms, such as FGG, MDK, RBP1, RBP2, IGFBP7, and SPON2. These features were key in differentiating specific developing intestinal cells, including epithelial, immune, mesenchymal, and vasculature cells of the colon, duo jejunum, and ileum cells. The classification rules showed special gene expression patterns on some intestinal cell types and the efficient classifiers can be useful tools for identifying intestinal cells.

The Intestine in Acute and Long COVID: Pathophysiological Insights and Key Lessons

Post-Acute Sequelae of SARS-CoV-2 infection (PASC), commonly known as Long COVID, represents a significant and complex health challenge with a wide range of symptoms affecting multiple organ systems. This review examines the emerging evidence suggesting a critical role of the gut and gut-brain axis in the pathophysiology of Long COVID. It explores how changes in the gut microbiome, disruption of gut barrier integrity, and the persistence of SARS-CoV-2 antigens within the gastrointestinal tract may contribute to the prolonged and varied symptoms seen in Long COVID, including chronic inflammation and neuropsychiatric disturbances. The review also summarizes key insights gained about Long COVID, highlighting its multifactorial nature, which involves immune dysregulation, microvascular damage, and autonomic nervous system dysfunction, with the gut playing a central role in these processes. While progress has been made in understanding these mechanisms, current evidence remains inconclusive. The challenges of establishing causality, standardizing research methodologies, and addressing individual variations in the microbiome are discussed, emphasizing the need for further longitudinal studies and more comprehensive approaches to enhance our understanding of these complex interactions. This review underscores the importance of personalized approaches in developing effective diagnostic and therapeutic strategies for Long COVID, while also acknowledging the significant gaps in our current understanding. Future research should aim to further unravel the complex interplay between the gut and Long COVID, ultimately improving outcomes for those affected by this condition.

Mastocytosis and intraepithelial lymphocytosis in the ileum and colon characterize chronic Toxoplasma gondii infection in mice

Toxoplasma gondii is the causative agent of toxoplasmosis, a common zoonotic disease affecting vertebrates with high global incidence. For the parasite to disseminate throughout the body, it crosses the intestinal barrier, triggering inflammatory reactions. This study aimed to assess the tissue response in the ileum and colon of mice following chronic infection with T. gondii. Fourteen mice were divided into two groups: the infected group received 1000 T. gondii oocysts via gavage, and after 60 days, the mice were euthanized. The ileum and colon were collected and processed for histological analysis, inflammatory marker measurement and myenteric neuron analysis. Chronic infection resulted in a significant increase in intraepithelial lymphocytes and mast cells, as well as morphometric changes such as increased total intestinal wall thickness of the ileum, crypt depth, collagen fiber area, and a decrease in myeloperoxidase activity, without altering nitric oxide levels. While the number of myenteric neurons remained unchanged, there was an increase in vasoactive intestinal peptide expression. These results suggest persistence intestinal inflammatory stimuli in chronic T. gondii infection.

Impact of arabinoxylan-enriched diets on the intestinal chemical barrier and microbiota composition in rainbow trout (Oncorhynchus mykiss)

Introduction

This study was conducted to evaluate the effects of dietary AX inclusion on the chemical barrier, antioxidant function and intestinal microbiome of rainbow trout.

Methods

Five isoproteic and isolipidic experimental diets were formulated to contain 0.03% arabinoxylanase, as well as 0%, 2.5%, 5% and 10% AX (CAX, Con, AX2.5, AX5 and AX10), respectively.

Results

The trypsin and maltase activities in the foregut of AX10 group were significantly lower than those in Con group. Similarly, the amylase and sucrase activities of the middle intestinal mucosa, maltase of the distal intestinal mucosa, and MUC2 mRNA levels of the middle and distal intestinal mucosa in AX10 group were also lower than those in Con group. Additionally, the levels of GSH, GST, MDA in the plasma, SOD and CAT in the middle and distal intestinal mucosa, as well as MDA in the middle intestinal mucosa, were significantly higher in AX10 group compared to the CAX and Con groups. Conversely, the levels of CAT, GSH-Px, IGF-1, mTOR, AST in the plasma and AMPD, GDH in the liver were significantly lower in AX10 group compared to the CAX and Con groups. Furthermore, the Chao 1, Shannon index, and the abundance of Cyanobacteria, Aurantimicrobium, Bacteroides decreased with the decreasing dietary AX content. In contrast, the abundance of Proteobacteria, Actinobacteria, and Stenotrophomonas were increased in AX10 group compared to Con group.

Discussion and conclusion

These results suggest that high AX (10%) diets may reduce the chemical barrier, antioxidant function, and protein metabolism in rainbow trout, while also reducing intestinal microbiome α-diversity and retarding the colonization of beneficial bacteria.

Dietary nucleic acids promote oral tolerance through innate sensing pathways in mice

Oral tolerance is essential for intestinal homeostasis and systemic immune function. However, our understanding of how oral tolerance is maintained is inadequate. Here we report that food-derived nucleic acids promote oral tolerance through innate sensing pathways. We find that dietary nucleic acids, but not microbiota, expand the natural intraepithelial lymphocyte (IEL) pool, specifically in the small intestine. TGF-β1, produced by natural IELs, then promotes activation of gut CD103+ dendritic cells to support the induction of antigen-specific Treg cells in a mouse model of OVA-induced oral tolerance. Mechanistically, MAVS and STING are redundantly required for sensing dietary RNAs and DNAs to activate downstream TBK1 signalling to induce IL-15 production, which results in the accumulation of natural IELs. Thus, our study demonstrates a key role of food-triggered innate sensing pathways in the maintenance of natural IELs and oral tolerance.

Branched Short-Chain Fatty Acid-Rich Fermented Protein Food Improves the Growth and Intestinal Health by Regulating Gut Microbiota and Metabolites in Young Pigs

The diet in early life is essential for the growth and intestinal health later in life. However, beneficial effects of a diet enriched in branched short-chain fatty acids (BSCFAs) for infants are ambiguous. This study aimed to develop a novel fermented protein food, enriched with BSCFAs and assess the effects of dry and wet ferment products on young pig development, nutrient absorption, intestinal barrier function, and gut microbiota and metabolites. A total of 18 young pigs were randomly assigned to three groups. The dry corn gluten-wheat bran mixture (DFCGW) and wet corn gluten-wheat bran mixture (WFCGW) were utilized as replacements for 10% soybean meal in the basal diet. Our results exhibited that the WFCGW diet significantly increased the growth performance of young pigs, enhanced the expression of tight junction proteins, and regulated associated cytokines expression in the colonic mucosa. Simultaneously, the WFCGW diet led to elevated levels of colonic isobutyric and isovaleric acid, as well as the activation of GPR41 and GPR109A. Furthermore, more potential probiotics including Lactobacillus, Megasphaera, and Lachnospiraceae_ND3007_group were enriched in the WFCGW group and positively associated with the beneficial metabolites such as 5-hydroxyindole-3-acetic acid. Differential metabolite KEGG pathway analysis suggested that WFCGW might exert gut health benefits by modulating tryptophan metabolism. In addition, the WFCGW diet significantly increased ghrelin concentrations in serum and hypothalamus and promoted the appetite of young pigs by activating hypothalamic NPY/AGRP neurons. This study extends the knowledge of BSCFAs and provides a reference for the fermented food application in the infant diet.

An injectable subcutaneous colon-specific immune niche for the treatment of ulcerative colitis

As a chronic autoinflammatory condition, ulcerative colitis is often managed via systemic immunosuppressants. Here we show, in three mouse models of established ulcerative colitis, that a subcutaneously injected colon-specific immunosuppressive niche consisting of colon epithelial cells, decellularized colon extracellular matrix and nanofibres functionalized with programmed death-ligand 1, CD86, a peptide mimic of transforming growth factor-beta 1, and the immunosuppressive small-molecule leflunomide, induced intestinal immunotolerance and reduced inflammation in the animals' lower gastrointestinal tract. The bioengineered colon-specific niche triggered autoreactive T cell anergy and polarized pro-inflammatory macrophages via multiple immunosuppressive pathways, and prevented the infiltration of immune cells into the colon's lamina propria, promoting the recovery of epithelial damage. The bioengineered niche also prevented colitis-associated colorectal cancer and eliminated immune-related colitis triggered by kinase inhibitors and immune checkpoint blockade.

The immune interactions of gut glycans and microbiota in health and disease

The human digestive system harbors a vast diversity of commensal bacteria and maintains a symbiotic relationship with them. However, imbalances in the gut microbiota accompany various diseases, such as inflammatory bowel diseases (IBDs) and colorectal cancers (CRCs), which significantly impact the well-being of populations globally. Glycosylation of the mucus layer is a crucial factor that plays a critical role in maintaining the homeostatic environment in the gut. This review delves into how the gut microbiota, immune cells, and gut mucus layer work together to establish a balanced gut environment. Specifically, the role of glycosylation in regulating immune cell responses and mucus metabolism in this process is examined.

Propionate-producing engineered probiotics ameliorated murine ulcerative colitis by restoring anti-inflammatory macrophage via the GPR43/HDAC1/IL-10 axis

Inflammatory bowel disease (IBD) is a chronic and unspecific inflammatory disorder of the gastrointestinal tract, and current treatment options often fail to maintain long-term remission. Studies have shown that propionate level is reduced in fecal samples from patients with IBD. Propionate can ameliorate IBD through intestinal epithelial cells and immune regulation, but its effects on the inflammatory microenvironment and macrophage differentiation have not been widely studied. To address this, we constructed an engineered propionate-producing probiotic (EcNP3) to achieve sustained restoration of propionate levels in the gut and increase its bioavailability. DSS-induced experimental intestinal inflammation model was used to evaluate the effect of EcNP3 on improving the intestinal mucosal barrier and increasing the proportion of anti-inflammatory macrophages. It was found that EcNP3 exhibited a restorative effect on the depletion of peritoneal anti-inflammatory macrophages (F4/80hiCD11bhi) and significantly improved the expression level of IL-10. Simultaneously, the expression of IL-1β, IL-6, and CXCL1 was downregulated while inhibiting apoptosis of tissue-resident macrophages ex vivo. Further investigation revealed that EcNP3 regulates IL-10 expression through G protein-coupled receptor 43 and histone deacetylase. Furthermore, EcNP3 significantly inhibited the protein expression of HDAC1 and promoted the histone acetylation level of cells. Finally, EcNP3 significantly improved DSS-induced colitis in mice by increasing mucus production and reducing inflammatory infiltration. Our results suggest that the engineered live biotherapeutic product EcNP3 is a safe and potently efficacious treatment for IBD, which defines a novel strategy in IBD therapy through macrophage IL-10 signaling.

A comprehensive immunobiology review of IBD: With a specific glance to Th22 lymphocytes development, biology, function, and role in IBD

The two primary forms of inflammatory disorders of the small intestine andcolon that make up inflammatory bowel disease (IBD) are ulcerative colitis (UC) and Crohn's disease (CD). While ulcerative colitis primarily affects the colon and the rectum, CD affects the small and large intestines, as well as the esophagus,mouth, anus, andstomach. Although the etiology of IBD is not completely clear, and there are many unknowns about it, the development, progression, and recurrence of IBD are significantly influenced by the activity of immune system cells, particularly lymphocytes, given that the disease is primarily caused by the immune system stimulation and activation against gastrointestinal (GI) tract components due to the inflammation caused by environmental factors such as viral or bacterial infections, etc. in genetically predisposed individuals. Maintaining homeostasis and the integrity of the mucosal barrier are critical in stopping the development of IBD. Specific immune system cells and the quantity of secretory mucus and microbiome are vital in maintaining this stability. Th22 cells are helper T lymphocyte subtypes that are particularly important for maintaining the integrity and equilibrium of the mucosal barrier. This review discusses the most recent research on these cells' biology, function, and evolution and their involvement in IBD.

Metatranscriptomic analysis indicates prebiotic effect of isomalto/malto-polysaccharides on human colonic microbiota in-vitro

Isomalto/malto-polysaccharides (IMMPs) are a novel type of soluble dietary fibres with a prebiotic potential promoting growth of beneficial microbes in the gut. However, the mode of action of IMMPs remains unknown. Previous studies on IMMPs showed an increase in total bacteria, especially lactobacilli, and higher production of short chain fatty acids (SCFA) when IMMPs were fed to rats or used during in vitro fermentation. Here we used metatranscriptomics to investigate how IMMPs with different amounts of α - (1 → 6) glycosidic linkages affected microbial function during incubation with human fecal inoculum. We showed that active microbial community dynamics during fermentation varied depending on the type of IMMP used and that the observed changes were reflected in the community gene expression profiles. Based on metatranscriptome analysis, members of Bacteroides, Lactobacillus and Bifidobacterium were the predominant degraders of IMMPs, and the increased gene expression in these bacteria correlated with high amounts of α - (1 → 6) glycosidic linkages. We also noted an increase in relative abundance of these bacteria and an activation of pathways involved in SCFA synthesis. Our findings could provide a baseline for more targeted approaches in designing prebiotics for specific bacteria and to achieve more controlled modulation of microbial activity towards desired health outcomes.

Revisiting the ethnomedicinal, ethnopharmacological, phytoconstituents and phytoremediation of the plant Solanum viarum Dunal

Solanum viarum, a perennial shrub, belongs to the family Solanaceae known for its therapeutic value worldwide. As a beneficial remedial plant, it is used for treating several disorders like dysentery, diabetes, inflammation, and respiratory disorders. Phytochemistry studies of this plant have shown the presence of steroidal glycoside alkaloids, including solasonine, solasodine, and solamargine. It also has flavonoids, saponins, minerals, and other substances. S. viarum extracts and compounds possess a variety of pharmacological effects, including antipyretic, antioxidant, antibacterial, insecticidal, analgesic, and anticancer activity. Most of the heavy metals accumulate in the aerial sections of the plant which is considered a potential phytoremediation, a highly effective method for the treatment of metal-polluted soils. We emphasize the forgoing outline of S. viarum, as well as its ethnomedicinal and ethnopharmacological applications, the chemistry of its secondary metabolites, and heavy metal toxicity. In addition to describing the antitumor activity of compounds and their mechanisms of action isolated from S. viarum, liabilities are also explained and illustrated, including any significant chemical or metabolic stability and toxicity risks. A comprehensive list of information was compiled from Science Direct, PubMed, Google Scholar, and Web of Science using different key phrases (traditional use, ethnomedicinal plants, western Himalaya, Himachal Pradesh, S viarum, and biological activity). According to the findings of this study, we hope that this review will inspire further studies along the drug discovery pathway of the chemicals extracted from the plant of S. viarum. Further, this review shows that ethnopharmacological information from ethnomedicinal plants can be a promising approach to drug discovery for cancer and diabetes.

A new approach: preventive protocols with yeast products and essential oils can reduce the in-feed use of antibiotics in growing-finishing pigs

The objective of this study was to evaluate the effects of yeast products (YP) and essential oils (EO) in total or partial replacement to in-feed antibiotic protocols (growth promoter and prophylactic), both in recommended doses and in overdose of prophylactic antibiotics (PA), on growth performance, and diarrhea incidence in the growing-finishing pigs; and fecal microbiota in market hogs. Four hundred pigs (20.36 ± 2.64 kg) were assigned to five treatments in a randomized block design: diets with prophylactic and growth promoter antibiotics (ANT); ANT with 30% more PA (ANT+30); diets with less PA and YP (ANT+Y); diets with less PA, YP and EO (ANT+Y+EO); and antibiotics-free diets with YP and EO (Y+EO). The content of the active components of the YP was 60% purified β-1,3/1,6-glucans extracted from Saccharomyces cerevisiae yeast (Macrogard), 20% functional water-soluble MOS (HyperGen), and 18% MOS, extracted from Saccharomyces cerevisiae yeast (ActiveMOS). From 0 to 14 d, pigs of the ANT+30, ANT+Y, and ANT+Y+EO treatments showed a greater body weight (BW) and average daily gain (ADG) compared to pigs from the Y+EO group. From 14 to 35 d, pigs of ANT+30 and ANT+Y+EO treatments were heavier than Y+EO group. At 105 d, ANT pigs had a higher BW than the Y+EO group. For the entire period, ADG of ANT pigs was greater, and feed conversion ratio better than Y+EO pigs. From 0 to 35 d, pigs of the Y+EO treatment showed a higher diarrhea incidence compared to pigs of the other groups. From 49 to 70 d, ANT+Y and ANT+Y+EO treatments showed a lower diarrhea incidence than Y+EO group, which remained the case during the overall period. At 105 d, the alpha diversity of fecal microbiota by Shannon Entropy was lower in ANT, ANT+30, and Y+EO groups than observed for ANT+Y+EO group. The abundance of Firmicutes phylum and Firmicutes/Bacteroidetes ratio was higher in ANT than in ANT+Y+EO pigs. Proteobacteria phylum abundance in ANT+Y+EO was higher than ANT, ANT+Y, and Y+EO. Peptostreptococcaceae family abundance was higher in ANT, ANT+30, and ANT+Y groups than in ANT+Y+EO and Y+EO groups. ANT+Y+EO and Y+EO groups show a lower abundance of SMB53 genus than ANT and ANT+30 groups. In conclusion, the use of YP and EO, in partial replacement to the in-feed antibiotic protocols, does not reduce the growth performance, can replace antibiotic growth promotors, and reduce the in-feed use of PA in growing-finishing pigs. The use of YP and EO, together with PA, increases the microbial diversity, despite having important genera for weight gain in less abundance. Overdose of PA does not improve growth performance and reduces microbial diversity, which does not characterize it as an efficient preventive protocol.

Probiotics an emerging therapeutic approach towards gut-brain-axis oriented chronic health issues induced by microplastics: A comprehensive review

Applications for plastic polymers can be found all around the world, often discarded without any prior care, exacerbating the environmental issue. When large waste materials are released into the environment, they undergo physical, biological, and photo-degradation processes that break them down into smaller polymer fragments known as microplastics (MPs). The time it takes for residual plastic to degrade depends on the type of polymer and environmental factors, with some taking as long as 600 years or more. Due to their small size, microplastics can contaminate food and enter the human body through food chains and webs, causing gastrointestinal (GI) tract pain that can range from local to systemic. Microplastics can also acquire hydrophobic organic pollutants and heavy metals on their surface, due to their large surface area and surface hydrophobicity. The levels of contamination on the microplastic surface are significantly higher than in the natural environment. The gut-brain axis (GB axis), through which organisms interact with their environment, regulate nutritional digestion and absorption, intestinal motility and secretion, complex polysaccharide breakdown, and maintain intestinal integrity, can be altered by microplastics acting alone or in combination with pollutants. Probiotics have shown significant therapeutic potential in managing various illnesses mediated by the gut-brain axis. They connect hormonal and biochemical pathways to promote gut and brain health, making them a promising therapy option for a variety of GB axis-mediated illnesses. Additionally, taking probiotics with or without food can reduce the production of pro-inflammatory cytokines, reactive oxygen species (ROS), neuro-inflammation, neurodegeneration, protein folding, and both motor and non-motor symptoms in individuals with Parkinson's disease. This study provides new insight into microplastic-induced gut dysbiosis, its associated health risks, and the benefits of using both traditional and next-generation probiotics to maintain gut homeostasis.

The Role of the Microbiota in the Pathogenesis and Treatment of Atopic Dermatitis-A Literature Review

Atopic dermatitis (AD) is a chronic inflammatory skin condition with a high prevalence worldwide. AD pathogenesis is complex and consists of immune system dysregulation and impaired skin barrier, influenced by genetic and environmental factors. The purpose of the review is to show the complex interplay between atopic dermatitis and the microbiota. Human microbiota plays an important role in AD pathogenesis and the course of the disease. Dysbiosis is an important factor contributing to the development of atopic diseases, including atopic dermatitis. The gut microbiota can influence the composition of the skin microbiota, strengthening the skin barrier and regulating the immune response via the involvement of bacterial metabolites, particularly short-chain fatty acids, in signaling pathways of the gut-skin axis. AD can be modulated by antibiotic intake, dietary adjustments, hygiene, and living conditions. One of the promising strategies for modulating the course of AD is probiotics. This review offers a summary of how the microbiota influences the development and treatment of AD, highlighting aspects that warrant additional investigation.

Inhibition of METTL3 in macrophages provides protection against intestinal inflammation

Inflammatory bowel disease (IBD) is prevalent, and no satisfactory therapeutic options are available because the mechanisms underlying its development are poorly understood. In this study, we discovered that increased expression of methyltransferase-like 3 (METTL3) in macrophages was correlated with the development of colitis and that depletion of METTL3 in macrophages protected mice against dextran sodium sulfate (DSS)-induced colitis. Mechanistic characterization indicated that METTL3 depletion increased the YTHDF3-mediated expression of phosphoglycolate phosphatase (PGP), which resulted in glucose metabolism reprogramming and the suppression of CD4+ T helper 1 (Th1) cell differentiation. Further analysis revealed that glucose metabolism contributed to the ability of METTL3 depletion to ameliorate colitis symptoms. In addition, we developed two potent small molecule METTL3 inhibitors, namely, F039-0002 and 7460-0250, that strongly ameliorated DSS-induced colitis. Overall, our study suggests that METTL3 plays crucial roles in the progression of colitis and highlights the potential of targeting METTL3 to attenuate intestinal inflammation for the treatment of colitis.

Recent progress on engineered micro/nanomaterials mediated modulation of gut microbiota for treating inflammatory bowel disease

Inflammatory bowel disease (IBD) is a type of chronic recurrent inflammation disease that mainly includes Crohn's disease and ulcerative colitis. Currently, the treatments for IBD remain highly challenging, with clinical treatment drugs showing limited efficacy and adverse side effects. Thus, developing drug candidates with comprehensive therapeutic effects, high efficiency, and low toxicity is urgently needed. Recently, micro/nanomaterials have attracted considerable interest because of their bioavailability, multitarget and efficient effects on IBD. In addition, gut modulation plays a substantial role in restoring intestinal homeostasis. Therefore, efficient microbiota-based strategies modulating gut microenvironment have great potential in remarkably treating IBD. With the development of micro- and nanomaterials for the treatment of IBD and more in-depth studies of their therapeutic mechanisms, it has been found that these treatments also have a tendency to positively regulate the intestinal flora, resulting in an increase in the beneficial flora and a decrease in the level of pathogenic bacteria, thus regulating the composition of the intestinal flora to a normal state. In this review, we first present the interactions among the immune system, intestinal barrier, and gut microbiome. In addition, recent advances in administration routes and methods that positively arouse the regulation of intestinal flora for IBD using probiotics, prebiotics, and redox-active micro/nanomaterials have been reviewed. Finally, the key challenges and critical perspectives of gut microbiota-based micro/nanomaterial treatment are also discussed.

Gut dysbiosis induced by florfenicol increases susceptibility to Aeromonas hydrophila infection in Zebrafish Danio rerio after the recommended withdrawal period

OBJECTIVE

Florfenicol (FFC) is a broad-spectrum antibiotic approved by the U.S. Food and Drug Administration to treat both systemic and external bacterial infections in food fish. The objective of this study was to evaluate the effect of FFC-medicated feed on the gut microbiota of Zebrafish Danio danio to determine (1) if the therapeutic dose of FFC-medicated feed induces dysbiosis and (2) if fish with altered gut microbiota were more susceptible to subsequent infection by the common opportunistic fish pathogen Aeromonas hydrophila.

METHODS

Zebrafish that were treated with regular and FFC-medicated feeds were artificially challenged with A. hydrophila at the end of the recommended 15-day antibiotic withdrawal period. The gut microbiota of the Zebrafish at different stages was analyzed using 16S ribosomal RNA gene sequencing.

RESULT

Our results found that FFC-medicated feed induced disruption of the gut microbiota. Dysbiosis was observed in all treated groups, with a significant increase in bacterial diversity, and was characterized by a remarkable bloom of Proteobacteria and a drastic decline of Mycoplasma and Cetobacterium in treated animals but without noticeable clinical signs or mortalities. In addition, the increase of Proteobacteria was not significantly reduced after the recommended 15-day withdrawal period, and the Zebrafish treated with FFC-medicated feed exhibited a significantly higher mortality rate when they were subsequently challenged with A. hydrophila compared to the control (regular feed) groups. Interestingly, the most dramatic changes in the gut microbiome composition occurred at the transition time between the late stage of the medicated treatment and the beginning of the withdrawal period instead of the time during the Aeromonas infection.

CONCLUSION

The administration of FFC-medicated feed at the recommended dose induced gut dysbiosis in Zebrafish, and fish did not recover to the baseline after the recommended withdrawal period. Our findings suggest that the use of antibiotics in fish elicits a response similar to those previously described in mammals and possibly makes the host more susceptible to subsequent infections of opportunistic pathogens. This study using a controlled model system suggests that antibiotics in aquaculture may have long-term effects on the general well-being of the fish.

Aspirin eugenol ester affects ileal barrier function, inflammatory response and microbiota in broilers under lipopolysaccharide-induced immune stress conditions

Aims

The aim of this study was to investigate the effects of aspirin eugenol ester (AEE) on ileal immune function in broilers under lipopolysaccharide (LPS)-induced immune stress.

Methods

Two hundred and forty one-day-old male Arbor Acres chicks were randomly divided into four groups (saline, LPS, saline + AEE and LPS + AEE) with six replicates of ten broilers each. The saline group and LPS group were fed the normal diet, while the other two groups received normal diet plus 0.1 g/kg AEE. Broilers in the LPS and LPS + AEE groups were injected intraperitoneally with 0.5 mg/kg B.W LPS in saline for seven consecutive days beginning at 14 days of age, while broilers in the saline and saline + AEE groups were injected with saline only.

Results

The results showed that AEE improved the ileal morphology and increased the ratio of villus height to crypt depth of immune-stressed broilers. LPS-induced immune stress significantly reduced the expression of the genes for the tight junction proteins occludin, zonula occludens-1 (ZO-1), claudin-1 and claudin-2, in the ileum, while AEE significantly up-regulated the expression of these genes. Compared with the saline group, the LPS-treated chickens showed significantly increased mRNA expression of the inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), cyclooxygenase-2 (COX-2), and microsomal Prostaglandin E Synthesase-1 (mPGES-1) in the ileum, while they were significantly decreased by AEE supplementation. In addition, analysis of the ileal bacterial composition showed that compared with saline and LPS + AEE groups, the proportion of Firmicutes and Lactobacillus in the LPS group was lower, while the proportion of Proteobacteria and Escherichia-Shigella was higher. Similarly, Line Discriminant Analysis Effect Size (LEfSe) analysis showed that compared with the LPS group, Brevibacillus was dominant in the saline group, while the LPS + AEE group was rich in Rhizobium, Lachnoclostridium, Ruminococcaceae, Faecalibacterium, Negativibacillus, Oscillospiraceae, and Flavonifractor.

Conclusion

These results indicate that dietary supplementation with 0.1 g/kg AEE could protect the intestinal health by improving the intestinal villus morphology, enhancing the expression of tight junction genes and alleviating inflammation to resist the immune stress caused by LPS stimulation in broilers, and the mechanism may involve COX-2-related signal transduction and improved intestinal microbiota composition.

E4BP4 in macrophages induces an anti-inflammatory phenotype that ameliorates the severity of colitis

Macrophages are versatile cells of the innate immune system that work by altering their pro- or anti-inflammatory features. Their dysregulation leads to inflammatory disorders such as inflammatory bowel disease. We show that macrophage-specific upregulation of the clock output gene and transcription factor E4BP4 reduces the severity of colitis in mice. RNA-sequencing and single-cell analyses of macrophages revealed that increased expression of E4BP4 leads to an overall increase in expression of anti-inflammatory genes including Il4ra with a concomitant reduction in pro-inflammatory gene expression. In contrast, knockout of E4BP4 in macrophages leads to increased proinflammatory gene expression and decreased expression of anti-inflammatory genes. ChIP-seq and ATAC-seq analyses further identified Il4ra as a target of E4BP4, which drives anti-inflammatory polarization in macrophages. Together, these results reveal a critical role for E4BP4 in regulating macrophage inflammatory phenotypes and resolving inflammatory bowel diseases.

Revitalizing Ancient Mitochondria with Nano-Strategies: Mitochondria-Remedying Nanodrugs Concentrate on Disease Control

Mitochondria, widely known as the energy factories of eukaryotic cells, have a myriad of vital functions across diverse cellular processes. Dysfunctions within mitochondria serve as catalysts for various diseases, prompting widespread cellular demise. Mounting research on remedying damaged mitochondria indicates that mitochondria constitute a valuable target for therapeutic intervention against diseases. But the less clinical practice and lower recovery rate imply the limitation of traditional drugs, which need a further breakthrough. Nanotechnology has approached favorable regiospecific biodistribution and high efficacy by capitalizing on excellent nanomaterials and targeting drug delivery. Mitochondria-remedying nanodrugs have achieved ideal therapeutic effects. This review elucidates the significance of mitochondria in various cells and organs, while also compiling mortality data for related diseases. Correspondingly, nanodrug-mediate therapeutic strategies and applicable mitochondria-remedying nanodrugs in disease are detailed, with a full understanding of the roles of mitochondria dysfunction and the advantages of nanodrugs. In addition, the future challenges and directions are widely discussed. In conclusion, this review provides comprehensive insights into the design and development of mitochondria-remedying nanodrugs, aiming to help scientists who desire to extend their research fields and engage in this interdisciplinary subject.

Validation of collection and anaerobic fermentation techniques for measuring prebiotic impact on gut microbiota

BACKGROUND

Defining the ability of prebiotic dietary carbohydrates to influence the composition and metabolism of the gut microbiota is central to defining their health impact in diverse individuals. Many clinical trials are using indirect methods. This study aimed to validate collection and fermentation methods enabling their use in the context of clinical studies.

METHODS AND RESULTS

Parameters tested included stool sample acquisition, storage, and growth conditions. Stool from 3 infants and 3 adults was collected and stored under varying conditions. Samples were cultured anaerobically for two days in the presence of prebiotics, whereupon optical density and pH were measured across time. Whole genome shotgun sequencing and NMR metabolomics were performed. Neither the type of collection vial (standard vial and two different BD anaerobic collection vials) nor cryopreservation (-80 °C or 4 °C) significantly influenced either microbial composition at 16 h of anaerobic culture or the principal components of the metabolome at 8 or 16 h. Metagenomic differences were driven primarily by subject, while metabolomic differences were driven by fermentation sugar (2'-fucosyllactose or dextrose).

CONCLUSIONS

These data identified a feasible and valid approach for prebiotic fermentation analysis of individual samples in large clinical studies: collection of stool microbiota using standard vials; cryopreservation prior to testing; and collecting fermentation read-out at 8 and 16 hr. Thus, fermentation analysis can be a valid technique for testing the effects of prebiotics on human fecal microbiota.

Targeting the "tumor microenvironment": RNA-binding proteins in the spotlight in colorectal cancer therapy

Colorectal cancer (CRC) is the third most common cancer and has the second highest mortality rate among cancers. The development of CRC involves both genetic and epigenetic abnormalities, and recent research has focused on exploring the ex-transcriptome, particularly post-transcriptional modifications. RNA-binding proteins (RBPs) are emerging epigenetic regulators that play crucial roles in post-transcriptional events. Dysregulation of RBPs can result in aberrant expression of downstream target genes, thereby affecting the progression of colorectal tumors and the prognosis of patients. Recent studies have shown that RBPs can influence CRC pathogenesis and progression by regulating various components of the tumor microenvironment (TME). Although previous research on RBPs has primarily focused on their direct regulation of colorectal tumor development, their involvement in the remodeling of the TME has not been systematically reported. This review aims to highlight the significant role of RBPs in the intricate interactions within the CRC tumor microenvironment, including tumor immune microenvironment, inflammatory microenvironment, extracellular matrix, tumor vasculature, and CRC cancer stem cells. We also highlight several compounds under investigation for RBP-TME-based treatment of CRC, including small molecule inhibitors such as antisense oligonucleotides (ASOs), siRNAs, agonists, gene manipulation, and tumor vaccines. The insights gained from this review may lead to the development of RBP-based targeted novel therapeutic strategies aimed at modulating the TME, potentially inhibiting the progression and metastasis of CRC.

Ferroptosis: Iron-mediated cell death linked to disease pathogenesis

Ferroptosis is an iron-mediated regulatory cell death pattern characterized by oxidative damage. The molecular regulating mechanisms are related to iron metabolism, lipid peroxidation, and glutathione metabolism. Additionally, some immunological signaling pathways, such as the cyclic GMP-AMP synthase-stimulator ofinterferon genes axis, Janus kinase-signal transducer and activator of transcription 1 axis, and transforming growth factor beta 1-Smad3 axis may also participate in the regulation of ferroptosis. Studies have shown that ferroptosis is closely related to many diseases such as cancer, neurodegenerative diseases, inflammatory diseases, and autoimmune diseases. Considering the pivotal role of ferroptosis-regulating signaling in the pathogenesis of diverse diseases, the development of ferroptosis inducers or inhibitors may have significant clinical potential for the treatment of the aforementioned conditions.

Unraveling the role of autophagy regulation in Crohn's disease: from genetic mechanisms to potential therapeutics

Autophagy serves as the primary intracellular degradation mechanism in which damaged organelles and self-cytoplasmic proteins are transported to the lysosome for degradation. Crohn's disease, an idiopathic chronic inflammatory disorder of the gastrointestinal tract, manifests in diverse regions of the digestive system. Recent research suggests that autophagy modulation may be a new avenue for treating Crohn's disease, and several promising small-molecule modulators of autophagy have been reported as therapeutic options. In this review, we discuss in detail how mutations in autophagy-related genes function in Crohn's disease and summarize the modulatory effects on autophagy of small-molecule drugs currently used for Crohn's disease treatment. Furthermore, we delve into the therapeutic potential of small-molecule autophagy inducers on Crohn's disease, emphasizing the prospects for development in this field. We aim to highlight the significance of autophagy modulation in Crohn's disease, with the aspiration of contributing to the development of more efficacious treatments that can alleviate their suffering, and improve their quality of life.

Microbial-Based Bioactive Compounds to Alleviate Inflammation in Obesity

The increased prevalence of obesity with several other metabolic disorders, including diabetes and non-alcoholic fatty liver disease, has reached global pandemic proportions. Lifestyle changes may result in a persistent positive energy balance, hastening the onset of these age-related disorders and consequently leading to a diminished lifespan. Although suggestions have been raised on the possible link between obesity and the gut microbiota, progress has been hampered due to the extensive diversity and complexities of the gut microbiota. Being recognized as a potential biomarker owing to its pivotal role in metabolic activities, the dysregulation of the gut microbiota can give rise to a persistent low-grade inflammatory state associated with chronic diseases during aging. This chronic inflammatory state, also known as inflammaging, induced by the chronic activation of the innate immune system via the macrophage, is controlled by the gut microbiota, which links nutrition, metabolism, and the innate immune response. Here, we present the functional roles of prebiotics, probiotics, synbiotics, and postbiotics as bioactive compounds by underscoring their putative contributions to (1) the reduction in gut hyperpermeability due to lipopolysaccharide (LPS) inactivation, (2) increased intestinal barrier function as a consequence of the upregulation of tight junction proteins, and (3) inhibition of proinflammatory pathways, overall leading to the alleviation of chronic inflammation in the management of obesity.

An Oral Nanomedicine Elicits In Situ Vaccination Effect against Colorectal Cancer

Oral administration is the most preferred approach for treating colon diseases, and in situ vaccination has emerged as a promising cancer therapeutic strategy. However, the lack of effective drug delivery platforms hampered the application of in situ vaccination strategy in oral treatment of colorectal cancer (CRC). Here, we construct an oral core-shell nanomedicine by preparing a silk fibroin-based dual sonosensitizer (chlorin e6, Ce6)- and immunoadjuvant (imiquimod, R837)-loaded nanoparticle as the core, with its surface coated with plant-extracted lipids and pluronic F127 (p127). The resultant nanomedicines (Ce6/R837@Lp127NPs) maintain stability during their passage through the gastrointestinal tract and exert improved locomotor activities under ultrasound irradiation, achieving efficient colonic mucus infiltration and specific tumor penetration. Thereafter, Ce6/R837@Lp127NPs induce immunogenic death of colorectal tumor cells by sonodynamic treatment, and the generated neoantigens in the presence of R837 serve as a potent in situ vaccine. By integrating with immune checkpoint blockades, the combined treatment modality inhibits orthotopic tumors, eradicates distant tumors, and modulates intestinal microbiota. As the first oral in situ vaccination, this work spotlights a robust oral nanoplatform for producing a personalized vaccine against CRC.

Microbiota Implications in Endocrine-Related Diseases: From Development to Novel Therapeutic Approaches

This comprehensive review article delves into the critical role of the human microbiota in the development and management of endocrine-related diseases. We explore the complex interactions between the microbiota and the endocrine system, emphasizing the implications of microbiota dysbiosis for the onset and progression of various endocrine disorders. The review aims to synthesize current knowledge, highlighting recent advancements and the potential of novel therapeutic approaches targeting microbiota-endocrine interactions. Key topics include the impact of microbiota on hormone regulation, its role in endocrine pathologies, and the promising avenues of microbiota modulation through diet, probiotics, prebiotics, and fecal microbiota transplantation. We underscore the importance of this research in advancing personalized medicine, offering insights for more tailored and effective treatments for endocrine-related diseases.

Mixed probiotics modulated gut microbiota to improve spermatogenesis in bisphenol A-exposed male mice

Bisphenol A (BPA), an environmental endocrine disruptor (EDC), has been implicated in impairing intestinal and male reproductive dysfunction. The efficacy of gut microbiota modulation for BPA-exposed testicular dysfunction has yet to be verified through research. Therefore, this study explored the potential of mixed probiotics in restoring spermatogenesis damage through the gut-testis axis under BPA exposure. We selected two probiotics strains (Lactobacillus rhamnosus and Lactobacillus plantarum) with BPA removal properties in vitro and the BPA-exposed male mice model was established. The probiotics mixture effectively reduced BPA residue in the gut, serum, and testis in mice. Through 16 S rDNA-seq and metabolomics sequencing, we uncovered that vitamin D metabolism and bile acid levels in the gut was abolished under BPA exposure. This perturbation was linked to an increased abundance of Faecalibaculum and decreased abundance of Lachnospiraceae_NK4A136_group and Ligilactobacillus. The probiotics mixture restored this balance, enhancing intestinal barrier function and reducing oxidative stress. This improvement was accompanied by a restored balance of short-chain fatty acids (SCFAs). Remarkably, the probiotics ameliorated testicular dysfunction by repairing structures of seminiferous tubules and reversing arrested spermiogenesis. Further, the probiotics mixture enhanced testosterone-driven increases in spermatogonial stem cells and all stages of sperm cells. Testicular transcriptome profiling linked these improvements to fatty acid degradation and peroxisome pathways. These findings suggest a significant interplay between spermatogenesis and gut microbiota, demonstrating that probiotic intake could be a viable strategy for combating male subfertility issues caused by BPA exposure.

Utility of human induced pluripotent stem cell-derived small intestinal epithelial cells for pharmacokinetic, toxicological, and immunological studies

The small intestine, which plays a crucial role in the absorption and metabolism of drugs and foods, serves as a target organ for drug-induced toxicity and immune interactions with functional foods and intestinal bacteria. Current alternative models of the human small intestine, such as Caco-2 cells and experimental animals, have limitations due to variations in the expression levels of metabolic enzymes, transporters, and receptors. This study presents investigations into the utility of human induced pluripotent stem cell-derived small intestinal epithelial cells (hiSIECs) for pharmacokinetic, toxicological, and immunological studies, respectively. While hiSIECs displayed small intestinal epithelial cell characteristics and barrier function, they demonstrated pharmacokinetic properties such as cytochrome P450 3A4/5 activity equivalent to human primary enterocytes and stable P-glycoprotein activity. These cells also demonstrated potential for assessing two forms of intestinal toxicity caused by anticancer drugs and gamma-secretase inhibitors, displaying immune responses mediated by toll-like and fatty acid receptors while serving as an inflammatory gut model through the addition of tumor necrosis factor alpha and interferon gamma. Overall, hiSIECs hold promise as an in vitro model for assessing pharmacokinetics, toxicity, and effects on the intestinal immunity of pharmaceuticals, functional foods, supplements, and intestinal bacteria.

Aged intestinal stem cells propagate cell-intrinsic sources of inflammaging in mice

Low-grade chronic inflammation is a hallmark of ageing, associated with impaired tissue function and disease development. However, how cell-intrinsic and -extrinsic factors collectively establish this phenotype, termed inflammaging, remains poorly understood. We addressed this question in the mouse intestinal epithelium, using mouse organoid cultures to dissect stem cell-intrinsic and -extrinsic sources of inflammaging. At the single-cell level, we found that inflammaging is established differently along the crypt-villus axis, with aged intestinal stem cells (ISCs) strongly upregulating major histocompatibility complex class II (MHC-II) genes. Importantly, the inflammaging phenotype was stably propagated by aged ISCs in organoid cultures and associated with increased chromatin accessibility at inflammation-associated loci in vivo and ex vivo, indicating cell-intrinsic inflammatory memory. Mechanistically, we show that the expression of inflammatory genes is dependent on STAT1 signaling. Together, our data identify that intestinal inflammaging in mice is promoted by a cell-intrinsic mechanism, stably propagated by ISCs, and associated with a disbalance in immune homeostasis.

Protective Effect and Mechanism of Aspirin Eugenol Ester on Lipopolysaccharide-Induced Intestinal Barrier Injury

Intestinal inflammation is a complex and recurrent inflammatory disease. Pharmacological and pharmacodynamic experiments showed that aspirin eugenol ester (AEE) has good anti-inflammatory, antipyretic, and analgesic effects. However, the role of AEE in regulating intestinal inflammation has not been explored. This study aimed to investigate whether AEE could have a protective effect on LPS-induced intestinal inflammation and thus help to alleviate the damage to the intestinal barrier. This was assessed with an inflammation model in Caco-2 cells and in rats induced with LPS. The expression of inflammatory mediators, intestinal epithelial barrier-related proteins, and redox-related signals was analyzed using an enzyme-linked immunosorbent assay (ELISA), Western blotting, immunofluorescence staining, and RT-qPCR. Intestinal damage was assessed by histopathological examination. Changes in rat gut microbiota and their functions were detected by the gut microbial metagenome. AEE significantly reduced LPS-induced pro-inflammatory cytokine levels (p < 0.05) and oxidative stress levels in Caco-2 cells and rats. Compared with the LPS group, AEE could increase the relative expression of Occludin, Claudin-1, and zonula occludens-1 (ZO-1) and decrease the relative expression of kappa-B (NF-κB) and matrix metalloproteinase-9. AEE could significantly improve weight loss, diarrhea, reduced intestinal muscle thickness, and intestinal villi damage in rats. Metagenome results showed that AEE could regulate the homeostasis of the gut flora and alter the relative abundance of Firmicutes and Bacteroidetes. Flora enrichment analysis indicated that the regulation of gut flora with AEE may be related to the regulation of glucose metabolism and energy metabolism. AEE could have positive effects on intestinal inflammation-related diseases.

Vitamin D3 induces stem cell activation via Lgr5-Bmi1 expression and improving mouse colitis histology index

Conventional therapy for inflammatory bowel disease using long-term anti-inflammatory drugs does not seem to provide optimal results. Adjuvant therapy using vitamin D3 is believed to have an essential role in repairing the colonic mucosa through the activation of colonic stem cells. The aim of this study was to demonstrate the effect of vitamin D3 in mucosal repair through stem cell activation, marked by leucin-rich repeat-containing G protein-coupled receptor 5 (Lgr5) and B lymphoma Mo-MLV insertion region 1 (Bmi1) expression and decrease the mouse colitis histology index (MCHI) score. In this study, 50 Mus musculus strain BALB/c were divided into five groups: negative control group, colitis group, and colitis groups with vitamin D3 administration of 0.2 mcg, 0.4 mcg, and 0.6 mcg per 25 g body weight for seven days. Dextran sulfate sodium (DSS) 5% was used to induce colitis. Lgr5-Bmi1 expression was measured using immunodoublestain fluorescent labeling method. Our data suggested that administration of vitamin D3 significantly increased expression of Lgr5-Bmi1 in the colonic mucosa. The colitis group treated with the highest dose of vitamin D3 (0.6 mcg/25 gram) showed the lowest MCHI score (3.60±0.64) while the lowest dose of vitamin D3 had the highest MCHI score (12.60±1.47). In conclusion, by stimulating stem cells, vitamin D3 administration stimulates mucosal regeneration, as demonstrated by upregulated expression of Lgr5-Bmi-1.

Exploring the Effects of Probiotic Treatment on Urinary and Serum Metabolic Profiles in Healthy Individuals

Probiotics are live microorganisms that confer health benefits when administered in adequate amounts. They are used to promote gut health and alleviate various disorders. Recently, there has been an increasing interest in the potential effects of probiotics on human physiology. In the presented study, the effects of probiotic treatment on the metabolic profiles of human urine and serum using a nuclear magnetic resonance (NMR)-based metabonomic approach were investigated. Twenty-one healthy volunteers were enrolled in the study, and they received two different dosages of probiotics for 8 weeks. During the study, urine and serum samples were collected from volunteers before and during probiotic supplementation. The results showed that probiotics had a significant impact on the urinary and serum metabolic profiles without altering their phenotypes. This study demonstrated the effects of probiotics in terms of variations of metabolite levels resulting also from the different probiotic posology. Overall, the results suggest that probiotic administration may affect both urine and serum metabolomes, although more research is needed to understand the mechanisms and clinical implications of these effects. NMR-based metabonomic analysis of biofluids is a powerful tool for monitoring host-gut microflora dynamic interaction as well as for assessing the individual response to probiotic treatment.