Faecalibacterium prausnitzii is an anti-inflammatory commensal bacterium identified by gut microbiota analysis of Crohn disease patients

PMA1-containing extracellular vesicles of Candida albicans triggers immune responses and colitis progression

Candida albicans (C. albicans) exhibits aberrant changes in patients with colitis, and it has been reported to dominate the colonic mucosal immune response. Here, we found that PMA1 expression was significantly increased in C. albicans from patients with IBD compared to that in healthy controls. A Crispr-Cas9-based fungal strain editing system was then used to knock out PMA1 expression in C. albicans. Compared to WT-C.a, ΔPMA1-C.a could not aggravate colitis. Proteomic analysis showed that PMA1 was transported by extracellular vesicles (EVs) of C. albicans. PMA1-containing EVs aggravated colitis, modulated the migration of cDC2 from the lamina propria to mesenteric lymph nodes, and induced TH17 cell differentiation. Moreover, the adaptor protein CARD9 was critical in PMA1-containing EV-induced colitis, and CARD9-deficient DCs did not induce TH17 cell differentiation or IL-17A production. Mechanically, CARD9 combines with the glycolytic protein GAPDH (aa2-146 domain) through its CARD region. CARD9 deficiency led to decreased enzyme activity of GAPDH and decreased glycolysis of DCs. These findings indicate that PMA1 is a potential virulence factor responsible for the pathogenesis of C. albicans colitis.

Synergistic and off-target effects of bacteriocins in a simplified human intestinal microbiome: implications for Clostridioides difficile infection control

Clostridioides difficile is a major cause of nosocomial diarrhea. As current antibiotic treatment failures and recurrence of infections are highly frequent, alternative strategies are needed for the treatment of this disease. This study explores the use of bacteriocins, specifically lacticin 3147 and pediocin PA-1, which have reported inhibitory activity against C. difficile. We engineered Lactococcus lactis strains to produce these bacteriocins individually or in combination, aiming to enhance their activity against C. difficile. Our results show that lacticin 3147 and pediocin PA-1 display synergy, resulting in higher anti-C. difficile activity. We then evaluated the effects of these L. lactis strains in a Simplified Human Intestinal Microbiome (SIHUMI-C) model, a bacterial consortium of eight diverse human gut species that includes C. difficile. After introducing the bacteriocin-producing L. lactis strains into SIHUMI-C, samples were collected over 24 hours, and the genome copies of each species were assessed using qPCR. Contrary to expectations, the combined bacteriocins increased C. difficile levels in the consortium despite showing synergy against C. difficile in agar-based screening. This can be rationally explained by antagonistic inter-species interactions within SIHUMI-C, providing new insights into how broad-spectrum antimicrobials might fail to control targeted species in complex gut microbial communities. These findings highlight the need to mitigate off-target effects in complex gut microbiomes when developing bacteriocin-based therapies with potential clinical implications for infectious disease treatment.

Precision microbiota therapy for IBD: premise and promise

Inflammatory Bowel Disease (IBD) is a spectrum of chronic inflammatory diseases of the intestine that includes subtypes of ulcerative colitis (UC) and Crohn's Disease (CD) and currently has no cure. While IBD results from a complex interplay between genetic, environmental, and immunological factors, sequencing advances over the last 10-15 years revealed signature changes in gut microbiota that contribute to the pathogenesis of IBD. These findings highlight IBD as a disease target for microbiome-based therapies, with the potential to treat the underlying microbial pathogenesis and provide adjuvant therapy to the emerging spectrum of advanced therapies for IBD. Building on the success of fecal microbiota transplantation (FMT) for Clostridioides difficile infection, therapies targeting gut microbiota have emerged as promising approaches for treating IBD; however, unique aspects of IBD pathogenesis highlight the need for more precision in the approach to microbiome therapeutics that leverage aspects of recipient and donor selection, diet and xenobiotics, and strain-specific interactions to enhance the efficacy and safety of IBD therapy. This review focuses on both pre-clinical and clinical studies that support the premise for microbial therapeutics for IBD and aims to provide a framework for the development of precision microbiome therapeutics to optimize clinical outcomes for patients with IBD.

Gut microbiome shifts in adolescents after sleeve gastrectomy with increased oral-associated taxa and pro-inflammatory potential

Bariatric surgery is highly effective in achieving weight loss in children and adolescents with severe obesity, however the underlying mechanisms are incompletely understood, and gut microbiome changes are unknown. Here, we show that adolescents exhibit significant gut microbiome and metabolome shifts several months after laparoscopic vertical sleeve gastrectomy (VSG), with increased alpha diversity and notably with enrichment of oral-associated taxa. To assess causality of the microbiome/metabolome changes in phenotype, pre-VSG and post-VSG stool was transplanted into germ-free mice. Post-VSG stool was not associated with any beneficial outcomes such as adiposity reduction compared pre-VSG stool. However, post-VSG stool exhibited a potentially inflammatory phenotype with increased intestinal Th17 and decreased regulatory T cells. Concomitantly, we found elevated fecal calprotectin and an enrichment of proinflammatory pathways in a subset of adolescents post-VSG. We show that in some adolescents, microbiome changes post-VSG may have inflammatory potential, which may be of importance considering the increased incidence of inflammatory bowel disease post-VSG.

Integrating multi-omics data to reveal the host-microbiota interactome in inflammatory bowel disease

Numerous studies have accelerated the knowledge expansion on the role of gut microbiota in inflammatory bowel disease (IBD). However, the precise mechanisms behind host-microbe cross-talk remain largely undefined, due to the complexity of the human intestinal ecosystem and multiple external factors. In this review, we introduce the interactome concept to systematically summarize how intestinal dysbiosis is involved in IBD pathogenesis in terms of microbial composition, functionality, genomic structure, transcriptional activity, and downstream proteins and metabolites. Meanwhile, this review also aims to present an updated overview of the relevant mechanisms, high-throughput multi-omics methodologies, different types of multi-omics cohort resources, and computational methods used to understand host-microbiota interactions in the context of IBD. Finally, we discuss the challenges pertaining to the integration of multi-omics data in order to reveal host-microbiota cross-talk and offer insights into relevant future research directions.

Gut microbiota and associated metabolites: key players in high-fat diet-induced chronic diseases

Excessive intake of dietary fats is strongly associated with an increased risk of various chronic diseases, such as obesity, diabetes, hepatic metabolic disorders, cardiovascular disease, chronic intestinal inflammation, and certain cancers. A significant portion of the adverse effects of high-fat diet on disease risk is mediated through modifications in the gut microbiota. Specifically, high-fat diets are linked to reduced microbial diversity, an overgrowth of gram-negative bacteria, an elevated Firmicutes-to-Bacteroidetes ratio, and alterations at various taxonomic levels. These microbial alterations influence the intestinal metabolism of small molecules, which subsequently increases intestinal permeability, exacerbates inflammatory responses, disrupts metabolic functions, and impairs signal transduction pathways in the host. Consequently, diet-induced changes in the gut microbiota play a crucial role in the initiation and progression of chronic diseases. This review explores the relationship between high-fat diets and gut microbiota, highlighting their roles and underlying mechanisms in the development of chronic metabolic diseases. Additionally, we propose probiotic interventions may serve as a promising adjunctive therapy to counteract the negative effects of high-fat diet-induced alterations in gut microbiota composition.

Faecalibacterium prausnitzii regulates carbohydrate metabolic functions of the gut microbiome in C57BL/6 mice

The probiotic impact of microbes on host metabolism and health depends on both host genetics and bacterial genomic variation. Faecalibacterium prausnitzii is the predominant human gut commensal emerging as a next-generation probiotic. Although this bacterium exhibits substantial intraspecies diversity, it is unclear whether genetically distinct F. prausnitzii strains might lead to functional differences in the gut microbiome. Here, we isolated and characterized a novel F. prausnitzii strain (UT1) that belongs to the most prevalent but underappreciated phylogenetic clade in the global human population. Genome analysis showed that this butyrate-producing isolate carries multiple putative mobile genetic elements, a clade-specific defense system, and a range of carbohydrate catabolic enzymes. Multiomic approaches were used to profile the impact of UT1 on the gut microbiome and associated metabolic activity of C57BL/6 mice at homeostasis. Both 16S rRNA and metagenomic sequencing demonstrated that oral administration of UT1 resulted in profound microbial compositional changes including a significant enrichment of Lactobacillus, Bifidobacterium, and Turicibacter. Functional profiling of the fecal metagenomes revealed a markedly higher abundance of carbohydrate-active enzymes (CAZymes) in UT1-gavaged mice. Accordingly, UT1-conditioned microbiota possessed the elevated capability of utilizing starch in vitro and exhibited a lower availability of microbiota-accessible carbohydrates in the gut. Further analysis uncovered a functional network wherein UT1 reduced the abundance of mucin-degrading CAZymes and microbes, which correlated with a concomitant reduction of fecal mucin glycans. Collectively, our results reveal a crucial role of UT1 in facilitating the carbohydrate metabolism of the gut microbiome and expand our understanding of the genetic and phenotypic diversity of F. prausnitzii.

New insights in amino sugar metabolism by the gut microbiome

Gut microorganisms inhabiting the intestinal tract play key roles in host's health and disease. A properly functioning gut microbiome requires the availability of adequate carbon, nitrogen and energy sources. One of the main sources of energy for intestinal bacteria are glycans, of which amino sugars are important components. Amino sugars are a class of carbohydrates in which one or more hydroxyl groups are substituted with amino groups. However, bacterial utilization of amino sugars and their impact on the gut microbiome and host health have not been thoroughly assessed. In this review, we summarize the latest discoveries about amino sugar metabolism by gut microbes, paying particular attention to the metabolism of N-acetyl-galactosamine (GalNAc), one of the most abundant amino sugars in the intestine, and its potential implications for microbial functionality and host health.

Gut Microbiota in Patients with Tuberculosis Associated with Different Drug Exposures of Antituberculosis Drugs

Interindividual variability in drug exposure can significantly influence treatment outcomes and may lead to drug concentration-related side effects during tuberculosis (TB) treatment. Although the gut microbiota is known to affect drug metabolism, its impact on anti-TB drugs has not been thoroughly explored. This study sought to elucidate the relationship between pre-treatment gut microbiota and drug exposure levels among patients with pulmonary TB. Two cohorts were analyzed: a discovery cohort (N = 99) and a validation cohort (N = 32), both comprising patients undergoing anti-TB therapy with rifampicin, isoniazid, pyrazinamide, and ethambutol. The gut microbiota patterns of participants from the discovery cohort and the validation cohort were profiled by 16S rRNA gene sequencing and metagenomics, respectively. Analyses of both cohorts robustly established a positive association between pre-treatment microbial diversity and drug exposure, as well as significant differences in gut microbiota composition across various drug exposure groups. At the species level, Faecalibacterium prausnitzii was positively associated with drug exposure to rifampicin. Moreover, functional analysis revealed that starch and sucrose metabolism and secondary bile acid biosynthesis were more abundant in the high drug exposure group. To identify biomarkers capable of stratifying patients based on their drug exposure levels, 11 taxa, represented by Faecalibacterium, were selected in the discovery cohort (AUC = 0.992) and were confirmed in the validation cohort with high predictive accuracy (AUC = 0.894). This study demonstrated a correlation between microbial dysbiosis and reduced exposure to anti-TB medications. Optimizing treatment by regulating gut microbiota to improve drug exposure levels requires further validation through larger scale multicenter clinical trials.

Omega-3 polyunsaturated fatty acids attenuate cognitive impairment via the gut-brain axis in diabetes-associated cognitive dysfunction rats

Diabetes-related cognitive dysfunction (DACD) is a comorbidity of type 2 diabetes that has a negative effect on patients' quality of life. Research has indicated that disruption of the gut microbiota (GM) may be linked to dementia with altered cognitive performance. Conversely, omega-3 polyunsaturated fatty acids (n-3 PUFAs) may reverse DACD. The present study aimed to assess the effects of an n-3 PUFA intervention and fecal microbiota transplantation (FMT) on high-fat and streptozotocin-induced DACD model rats. In DACD rats, n-3 PUFA treatment restored fasting blood glucose (FBG) levels and cognitive function, increased the expression of anti-inflammatory cytokines and downregulated the expression of proinflammatory cytokines in the cortex and colon. Additionally, the expression of the postsynaptic density protein-95 mRNA and protein varied with n-3 PUFA treatment. Treatment with n-3 PUFAs also increased the expression of tight junction proteins. Beneficial and short-chain fatty acid-producing bacteria were more abundant when rats were exposed to n-3 PUFAs. After FMT from the rats with DACD symptoms that were improved by the n-3 PUFA dietary intervention into another batch of DACD rats, we observed recovery in recipient DACD rats. These results indicated that the alleviation of DACD symptoms by n-3 PUFAs was attributed to gut microbiota remodeling.

Positive nutritional selection of adults with healthy lifestyle and high daily fiber consumption for the isolation of beneficial intestinal bacteria: The iTARGET cohort study protocol

Recent advances in the study of the gut microbiota has pointed to its under-utilized source of potentially beneficial bacteria, known as next generation probiotics, offering a promising avenue to restore or compensate impaired gut microbiota toward a healthy state. Aside from the difficulties to achieve in-lab adequate culture conditions, the use of beneficial bacterial isolates is also limited by their bioavailability in the donor itself. In the iTARGET study, we positively selected donors based on their diet enriched in fiber, that has been shown to increase the prevalence of bacterial species associated with health. The iTARGET study is a monocenter, prospective, observational study of adults with healthy lifestyle and high daily fiber consumption. We aim to recruit individuals in two phases, the first one for all individuals that will permit the identification of carriers for bacteria of interest and the second phase for a subset of individuals to allow for culture and isolation of previously identified potentially beneficial bacteria. Our primary outcome is the isolation and culture of at least one potentially beneficial isolate. The secondary outcomes comprised the high throughput metagenomic profiles of the intestinal microbiota and the characterization of the cultured isolates. The study was approved by the French Research Ethics Committees (Comité de Protection des Personnes Sud-Est I) under the National reference ID 2023-A01677-38. Study findings and results will be published in peer-reviewed Open Access journals. (Trial registration number on ClinicalTrials.gov: NCT06166810).

Modulation of Intestinal Flora: a Novel Immunotherapeutic Approach for Enhancing Thyroid Cancer Treatment

Over the past 3 years, there has been a growing interest in clinical research regarding the potential involvement of intestinal flora in thyroid cancer (TC). This review delves into the intricate connection between intestinal flora and TC, focusing on the particular intestinal flora that is directly linked to the disease and identifying which may be able to predict potential microbial markers of TC. In order to shed light on the inflammatory pathways connected to the onset of TC, we investigated the impact of intestinal flora on immune modulation and the connection between chronic inflammation when investigating the role of intestinal flora in the pathogenesis of TC. Furthermore, the potential role of intestinal flora metabolites in the regulation of thyroid function was clarified by exploring the effects of short-chain fatty acids and lipopolysaccharide on thyroid hormone synthesis and metabolism. Based on these findings, we further explore the effects of probiotics, prebiotics, postbiotics, vitamins, and trace elements.

Fecal microbiota transplantation as a potential therapeutic approach to improve impaired glucose tolerance via gut microbiota modulation in rat model

Objectives

To investigate the impact of diet-induced gut microbiota alterations on type 2 diabetes and assess the therapeutic potential of Fecal Microbiota Transplantation (FMT) in restoring a balanced gut microenvironment.

Methods

To induce type 2 diabetes, rats were fed a high-sugar high-fat diet (HSFD) for 90 days. After diabetes induction, animals were divided into an HSFD control group, a metformin group (100 mg/kg), and an FMT group (100 mg/kg), receiving treatment for an additional 90 days. Fasting blood glucose levels, glucose tolerance, serum markers (HbA1C, free fatty acids, lipopolysaccharides, pro-inflammatory and anti-inflammatory cytokines), and gut microbiota profiles via cecal metagenome sequencing were analyzed post-treatment.

Results

FMT effectively restored gut microbiota composition to a profile similar to healthy controls, rebalancing the Firmicutes/Bacteroidetes ratio and increasing beneficial taxa, including Prevotella ruminicola, Akkermansia muciniphila, Roseburia, and Faecalibacterium prausnitzii. These microbial shifts corresponded with significant metabolic improvements: FMT reduced inflammatory markers (LPS and FFA), lowered HbA1c, and improved glucose tolerance. Enhanced gut barrier integrity observed in FMT-treated animals likely contributed to reduced endotoxemia and systemic inflammation, distinguishing FMT's metabolic effects from those of metformin. Notably, FMT addressed the dysbiosis associated with HSFD, promoting microbial resilience and mitigating the metabolic disruptions linked to type 2 diabetes.

Conclusion

These findings underscore the potential of FMT as a targeted therapeutic approach to modulate gut microbiota composition and mitigate metabolic dysregulation induced by high sugar high fat diet.

Fire in the belly: Stress and antibiotics induce dysbiosis and inflammation in the gut of common carp

Fish are exposed to numerous stressors which negatively affect their immune response and increase infection susceptibility. The risk of bacterial infections results in the excessive and preventive use of antibiotics. Therefore, we aimed to study how antibiotic treatment and restraint stress will affect the stress response, microbiota composition, gut morphology, and inflammatory reaction in common carp. Both restraint stress and antibiotic treatment increased cortisol level. Moreover, antibiotics induced dysbiosis in fish gut, manifested by a decrease in the total abundance of bacteria, and a shift in bacteria diversity, including a reduced number of Aeromonas, Bacteroides, Barnesiellaceae, Cetobacterium and Shewanella and an increased abundance of Flavobacterium. To a lesser extent, stress modified gut microbiota, as it decreased bacteria number and slightly changed the microbiota composition by decreasing Cetobacterium abundance and increasing Vibrio abundance. Microbiota of the antibiotic-treated and stressed fish shifted from the beneficial bacterial genera - Cetobacterium and Bacteroides, to the increased presence of unfavorable bacteria such as Brevinema, Flavobacterium and Desulfovibrionaceae. Stress and antibiotic-induced changes in the gut microbiota were related to the changes in the gut morphology when the higher abundance of goblet and rodlet cells and increased secretion activity of goblet cells were observed. Moreover, up-regulation of the expression of genes encoding pro-inflammatory mediators and cytokines involved in the Th17 immune response was present in the gut of the antibiotic-treated and stressed fish. We conclude that in carp antibiotics and stress alter the abundance and composition of the microbiota and induce Th17-dependent inflammatory reaction in the gut. Moreover, our results strongly suggest the interplay of the stress axis and the brain-gut-microbiota axis.

Role and mechanism of gut microbiota-host interactions in the pathogenesis of Crohn's disease

BACKGROUND

Crohn's disease (CD) is a chronic, nonspecific inflammatory bowel disease with a poor prognosis. Despite its increasing incidence, curing CD remains challenging due to its complex etiology and unclear pathogenesis.

METHODS

A comprehensive PubMed and Web of Science search was conducted using the keywords Crohn's disease, gut microbiota, dysbiosis, pathogenesis and treatment, focusing on studies published between 2014 and 2024.

RESULTS

Recent studies have demonstrated a close relationship between gut microbiota dysbiosis and the development of CD. Although many dysbioses associated with CD have not yet been proven to be causal or consequential, it has been observed that the gut microbiota in CD patients exhibits reduced diversity, a decrease in beneficial bacteria, and an increase in pathogenic bacteria. These changes may lead to decreased intestinal barrier function, abnormal immune responses, and enhanced inflammatory reactions, which are related to the disease's activity, phenotype, drug treatment efficacy, and postoperative therapeutic outcomes. Therefore, further exploration of the microbiota-host interactions and the pathogenesis of CD, the identification of biomarkers, and the development of targeted strategies for modulating the gut microbiota could offer new avenues for the prevention and treatment of CD.

CONCLUSIONS

This review highlights the pivotal role of gut microbiota dysbiosis in driving CD pathogenesis and its progression, while underscoring its potential as a therapeutic target through dietary modulation, microbial interventions, and integrative strategies to improve clinical management and prognostic outcomes.

Intestinal Microbes, Metabolites, and Hormones in Alcohol-Associated Liver Disease

Alcohol-associated liver disease (ALD)-encompassing conditions including steatosis, fibrosis, cirrhosis, and hepatocellular carcinoma-refers to hepatic damage arising from excessive or hazardous alcohol consumption, and is now recognized as a significant global health burden. Although the mechanisms underlying ALD remain incompletely understood, several pathways have been substantiated over the last five decades, notably the involvement of intestinal microorganisms and the involvement of the gut-liver axis in alcohol metabolism and ALD pathogenesis. Ethanol intake disrupts the intestinal microbial balance and compromises the gut barrier, resulting in increased permeability to microbial products. The subsequent translocation of microbial metabolites and other antigenic substances to the liver activates hepatic immune responses, thereby contributing to liver injury. In addition, gastrointestinal hormones are also implicated in ALD progression through various mechanisms. Although no therapies for ALD have been approved by the Food and Drug Administration, various therapeutic strategies targeting the intestinal microbiota and gut barrier have been identified. In conclusion, this review discusses the role of the gut-liver axis in alcohol metabolism and ALD pathogenesis and explores the emerging therapeutic strategies.

Unravelling the gut-brain connection: a systematic review of migraine and the gut microbiome

BACKGROUND

There is substantial evidence linking migraines to gastrointestinal (GI) issues. Conditions such as irritable bowel syndrome and colitis often co-occur with migraines and GI symptoms are common among migraine patients. However, the evidence supporting the efficacy of gut microbiome-targeted therapies for managing migraines is limited. This systematic review aimed to describe the existing evidence of the gut microbiome in patients with migraine compared to healthy individuals. Additionally, it sought to examine how therapies targeting the gut microbiome including prebiotics, probiotics and synbiotics, might influence clinical outcomes.

METHODS

We performed searches on Embase, PubMed, and the Cochrane Library to identify studies in migraines and the gut microbiome, focusing on those which investigated the gut microbiome composition and gut microbiome-targeted therapies. Key data was extracted and analysed including study details, patient demographics, migraine type, comorbidities, and clinical outcomes. For gut microbiome composition studies, bacterial diversity and abundance was noted. For gut microbiome-targeted therapies studies, treatment types, dosages, and patient outcomes was recorded.

RESULTS

A significant difference between various genera of microbes was reported between migraine patients and controls in several studies. Bacteroidetes (also named Bacteroidota), proteobacteria, and firmicutes (also named Bacillota) phyla groups were found significantly abundant in migraine, while studies were conflicted in the abundance of Actinobacteria and Clostridia with regards to increased migraine risk in migraine patients. Patients with migraine had a gut microbiome with reduced species number and relative abundance, as well as a distinct bacterial composition compared to controls. Synbiotic and synbiotic/probiotic combination treatments have been shown in five randomised controlled trials and one open label pilot study to significantly decrease migraine severity, frequency, duration and painkiller consumption.

CONCLUSIONS

The significant alterations in microbial phyla observed in migraine patients suggest a potential microbial signature that may be associated with migraine risk or chronic progression. However, the mechanistic underpinnings of these associations remain unclear. This systemic review found that probiotic and synbiotic/probiotic combination therapies may be promising interventions for migraine management, offering significant reductions in migraine frequency and painkiller use. Future randomised controlled studies are needed to evaluate the optimal length of treatment and impact on patient related quality of life.

Massive acquisition of conjugative and mobilizable integrated elements fuels Faecalibacterium plasticity and hints at their adaptation to the gut

Faecalibacterium is one of the most abundant bacteria of the human gut microbiota of healthy adults and is recognized to have positive effects on health. Here, we precisely and comprehensively analyzed the conjugative mobilome of four complete Faecalibacterium genomes. Despite lacking any plasmid, these bacteria harbor a vast arsenal of 130 elements, including 17 integrative and conjugative elements (ICEs) and 83 integrative and mobilizable elements (IMEs), collectively comprising 14-23% of the genome. Genome comparison of two strains isolated from the same fecal sample (Faecalibacterium and Roseburia strains) revealed almost identical elements indicating that transfer of ICEs and IMEs shape gut microbiome. ICEs and IMEs from Faecalibacterium encode many and diverse predicted functions such as defense and stress response (phages, multidrug, antibiotics, oxidative stress, biliar salts, antimicrobial peptides), nutrient import and metabolisms (Fe3+, carbohydrates) and riboflavin synthesis. This hints at their important role in the survival and adaptation of Faecalibacterium strains to the gut ecosystem. A rapid survey of 29 additional Faecalibacterium genomes uncovered many putative ICEs and IMEs, reinforcing their role in the rapid and massive evolution of Faecalibacterium genomes.

Harnessing the Microbiome: CRISPR-Based Gene Editing and Antimicrobial Peptides in Combating Antibiotic Resistance and Cancer

The growing crisis of antibiotic resistance and the increasing incidence of cancer have prompted the exploration of innovative approaches, such as gene editing and antimicrobial peptides (AMPs). The human microbiome is integral to various aspects of health, disease, and therapeutic development, influencing metabolic pathways, immune function, and pathogen resistance. Recent advances in gene editing technologies, particularly CRISPR (clustered regularly interspaced short palindromic repeats), have opened new avenues for leveraging the microbiome to address complex medical challenges, including combating multidrug-resistant pathogens and cancer. The microbiome plays a crucial role in combating antibiotic resistance by modulating microbial communities, influencing pathogen survival and susceptibility to treatments. This review explores the microbiome's dynamic role in metabolic regulation, its contribution to cancer management, and how AMPs help maintain homeostasis and exhibit emerging anticancer properties, supported by both preclinical findings and clinical evidence. Additionally, CRISPR-based microbiome engineering offers potential to enhance host-microbiome interactions, optimizing therapeutic outcomes. The integration of microbiome metagenomics and proteomics has led to the discovery of novel AMPs with targeted anticancer effects. Innovative strategies, such as engineered probiotics and CRISPR-based microbiome engineering, present exciting prospects for next-generation therapies. Despite these advances, the translation of microbiome-based therapies into clinical settings remains challenging due to ethical, regulatory, and ecological hurdles. This review underscores the transformative potential of microbiome-based interventions, emphasizing the role of personalized medicine in maximizing therapeutic efficacy. Furthermore, we also address critical research gaps, limitations, and future directions, including optimizing AMP stability, delivery, and bioavailability, as well as overcoming the regulatory and ethical challenges in clinical translation.

Pharmacokinetic and pharmacodynamic alterations in older people: what we know so far

INTRODUCTION

Healthcare professionals face increasing challenges when managing older patients, a group characterized by significant interindividual variability in comorbidity patterns, homeostatic capacity, frailty status, cognitive function, and life expectancy. Complex therapeutic decisions may increase the risk of inappropriate polypharmacy, drug-drug, and drug-disease interactions in the context of age-associated pharmacokinetic and pharmacodynamic alterations, with consequent drug accumulation and toxicity.

AREAS COVERED

This state-of-the-art narrative review article summarizes and critically appraises the results of original research studies and reviews published in PubMed, Scopus, and Web of Science, from inception to 9 April 2025, on age-associated changes in critical organs and systems and relevant pharmacokinetic and pharmacodynamic alterations. It also discusses the emerging role of frailty and the gut microbiota in influencing such alterations and the potential utility of machine learning techniques in identifying new signals of drug efficacy and toxicity in older patients.

EXPERT OPINION

The available knowledge regarding specific age-associated pharmacokinetic and pharmacodynamic alterations applies to a limited number of drugs, some of which are not frequently prescribed in contemporary practice. Future studies investigating a wider range of drugs and their patterns of use will likely enhance therapeutic efficacy and minimize toxicity in the older patient population.

Multi-omics analyses reveal differences in intestinal flora composition and serum metabolites in Cherry Valley broiler ducks of different body weights

Fledgling broiler ducks vary in body weight and growth rate. The aim of this study was to investigate the relationship between serum metabolites and the intestinal microbiota in Cherry Valley broiler ducks with different finishing weights and to reveal differences in their metabolic regulation and microbial composition. Serum and cecum content samples were collected from Cherry Valley broiler ducks of different finishing weights. Metabolites were identified and compared using untargeted metabolomics, 16S rRNA gene sequencing, multivariate statistics and bioinformatics. Six key findings emerged. First, serum biochemical parameters showed that AST and ALT levels were significantly lower in the high weight group (Group H) than in the low weight group (Group L), and serum immunoglobulin IgG levels were significantly higher in group H. Second, the chorionic height to crypt depth ratio of the duodenum was significantly higher in group H than in group L. Third, the gut microbial community diversity or abundance was lower in broiler ducks in group L. Fourth, LEfSe analysis showed that the biomarker for group L was Streptococcus, whereas for group H it was Faecalibacterium. Fifth, a total of 127 differential metabolites were identified (49 up-regulated and 78 down-regulated). Finally, Spearman's correlation analysis showed that Spearman's correlation analyses showed that the Lipid-related serum metabolites were higher in low-body recombinant broiler ducks, mainly Lathosterol, Cholesterol, Cynaratriol and Leukotriene B4. In addition to lipid-associated serum metabolites in high-body recombination, The water-soluble vitamin-like metabolite Pantothenate and the antibiotic-like metabolite Tylosin were high. The cecum microbiota is strongly associated with metabolites, especially Faecalibacterium, unclassified Tannerellaceae, Subdoligranulum, Alistipes, and [Ruminococcus] torques_group, with which it exhibits strong Correlation. Broiler ducks with higher body weights have a better intestinal villous structure, enhanced digestion and absorption, higher levels of immunoglobulin secretion and superior growth performance. Broiler ducks with different body weights differed in plasma metabolites and cecum flora. Spearman's correlation analyses showed that the Correlation between differential metabolites and differential gut microbial genera.

Updated Insights into Probiotic Interventions for Metabolic Syndrome: Mechanisms and Evidence

Metabolic syndrome (MetS) is a disease with complex and diverse etiologies. Extrinsic factors such as diet and lifestyle can induce dysbiosis of gut microbes, compromising intestinal barrier integrity and leading to inflammation and insulin resistance, thereby advancing MetS. Probiotic interventions have shown potential in ameliorating gut microbiota dysbiosis and regulating host metabolism by assimilating lipids, metabolizing carbohydrates, and producing short-chain fatty acids (SCFA), indole compounds, secondary bile acids, conjugated linoleic acid (CLA), and other active ingredients. An increasing number of new strains are being isolated and validated for their effective roles intervening on MetS in animal and population studies. This review aims to provide updated insights into the pathogenic mechanisms of MetS, highlight the newly identified probiotic strains that have demonstrated improvements in MetS, and elucidate their mechanisms of action, with the aim of offering contemporary perspectives for the future use of probiotics in mitigating MetS.

HiBC: a publicly available collection of bacterial strains isolated from the human gut

Numerous bacteria in the human gut microbiome remain unknown and/or have yet to be cultured. While collections of human gut bacteria have been published, few strains are accessible to the scientific community. We have therefore created a publicly available collection of bacterial strains isolated from the human gut. The Human intestinal Bacteria Collection (HiBC) ( https://www.hibc.rwth-aachen.de ) contains 340 strains representing 198 species within 29 families and 7 phyla, of which 29 previously unknown species are taxonomically described and named. These included two butyrate-producing species of Faecalibacterium and new dominant species associated with health and inflammatory bowel disease, Ruminococcoides intestinale and Blautia intestinihominis, respectively. Plasmids were prolific within the HiBC isolates, with almost half (46%) of strains containing plasmids, with a maximum of six within a strain. This included a broadly occurring plasmid (pBAC) that exists in three diverse forms across Bacteroidales species. Megaplasmids were identified within two strains, the pMMCAT megaplasmid is globally present within multiple Bacteroidales species. This collection of easily searchable and publicly available gut bacterial isolates will facilitate functional studies of the gut microbiome.

Clostridium butyricum-induced balance in colonic retinol metabolism and short-chain fatty acid levels inhibit IgA-related mucosal immunity and relieve colitis developments

Gut microbiota and their metabolites play a significant role in inflammatory bowel disease. Here, we attempted to determine the anti-inflammatory role of the probiotic Clostridium. butyricum (CB) in inflammatory bowel disease and identify the exact immune mechanism. The clinical significance of Clostridiales and CB was explored in patients with ulcerative colitis. The inflammation-suppressive role of CB was evaluated in mice with DSS-induced colitis. 16S rRNA sequencing was performed to assess changes in the gut microbiota. Altered transcription levels were detected by RNA sequencing. Flow cytometry was performed to assess the frequency of IgA responses to gut microbiota. Clostridiales and CB were depleted in ulcerative colitis. Oral gavage with CB significantly suppressed weight loss and colon shortening in the dextran sulfate sodium-induced colitis mouse model. Intestinal barrier injury was reversed and the gut microbiota was restored upon treatment with CB administration. The mucosal immune response to gut microbiota was reversed upon treatment with CB. CB conditional medium was more effective than heat-killed CB in alleviating inflammation. Mechanistically, retinol metabolism and retinoic acid levels were higher in groups treated with CB and butyrate. CB and the metabolite butyrate exerted a suppressive role on the abundance of Immunoglobulin A-coated gut microbiota by inhibiting retinoic acid synthesis. In summary, CB protects against inflammation and intestinal barrier injury by producing anti-inflammatory metabolites that can regulate the mucosal immune response to gut microbiota by increasing retinoic acid levels in the colon.

Startups and the next frontier of inflammatory bowel disease therapy: a guide for the brave

PURPOSE OF REVIEW

This review explores the evolving landscape of inflammatory bowel disease (IBD) therapy, particularly through the lens of startups that are pushing the boundaries of current treatment paradigms. By discussing the challenges and opportunities faced by startups, this review seeks to provide insights for aspiring entrepreneurs and innovators in the IBD space.

RECENT FINDINGS

The landscape of IBD is rapidly evolving, with innovative solutions ranging from novel therapeutics to digital health platforms. An analysis of recent SBIR award winners highlights emerging trends, including microbiome-based therapies, targeted small molecules, and advanced drug delivery systems like hydrogels. Digital health solutions, such as smart monitoring tools and AI-assisted treatment selection are gaining traction. IBD startups are playing a crucial role in cost reduction through competition, streamlining drug development, and treatment personalization. Despite regulatory, financial, and funding challenges, startups are driving the next phase of IBD innovation.

SUMMARY

The future of IBD therapy is being driven by innovative start-ups that are challenging the status quo in IBD treatment. These companies are addressing critical gaps in therapy by focusing on novel drug targets, improved drug delivery, and precision medicine. While startups face many challenges including high research and development (R&D) costs, regulatory hurdles, and funding, they continue to be at the forefront of IBD innovation. Their success could potentially lead to more affordable and effective therapies. By drawing on examples like the nutraceutical company, Evinature, my own personal experience as technical lead of Edulis, a startup focused on localized IBD therapy, and perspective from the head of the Crohn's and Colitis Foundation's IBD Ventures, this review aims to provide insights for those looking to innovate in IBD.

Exploring the anti-inflammatory effects of microencapsulated probiotic bacteria: in vivo and in vitro evaluation in healthy mouse models

BACKGROUND

Encapsulation technology has been extensively employed in recent years to enhance the efficacy and efficiency of probiotics. Nevertheless, existing studies have primarily concentrated on product efficacy, with inadequate scrutiny concerning potential effects on living organisms. This study aimed to evaluate the effects of various encapsulated probiotic strains on inflammatory responses in healthy mice, alongside their in vitro viability. Nissle (EcN) and Lactobacillus rhamnosus GG (LGG) were microencapsulated for the study.

RESULTS

The differences in serum levels of Total Oxidant Status, Total Antioxidant Status, and C-reactive protein among the groups were statistically significant (LGG, P = 0.039, P = 0.024, and P < 0.001; EcN, P = 0.019, P = 0.012, and P = 0.037, respectively). The highest levels were found in the control group, while the lowest levels were observed in the microencapsulated group. There were no significant differences in tissue tumor necrosis factor or interleukin-6 levels for either LGG or EcN.

CONCLUSION

Probiotics reduced inflammation-related parameters in serum of healthy mice. Microencapsulation preserved viability in vitro, but in vivo no significant differences were observed in anti-inflammatory parameters or body weight between microencapsulated and free probiotics. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Vitamin C improves gut Bifidobacteria in humans

Aims: Numerous beneficial effects of vitamin C (ascorbic acid) supplementation have been reported in the literature. However, data on its effects toward the gut microbiome are limited. We assessed the effect of vitamin C supplementation on the abundance of beneficial bacterial species in the gut microbiome. Materials and methods: Stool samples were analyzed for relative abundance of gut microbiome bacteria using next-generation sequencing-based profiling and metagenomic shotgun analysis. Results: Supplementation with vitamin C increased the abundance of bacteria of the genus Bifidobacterium (p = 0.0001) and affected various species. Conclusion: The beneficial effects of vitamin C supplementation may be attributed to modulation of the gut microbiome and the consequent health benefits thereof.

Increased fecal glycocholic acid levels correlate with obesity in conjunction with the depletion of archaea: The Dosanco Health Study

Recent studies have focused on the relationship between obesity and gut microbiota. This study aims to identify fecal components and gut bacterial species associated with different BMI categories. In this study, 538 participants aged ≥18 years were categorized into underweight, normal, and obese groups based on BMI (cutoffs: 18.5 and 25.0 kg/m²). We compared 30 fecal components among these groups and calculated correlation coefficients between each component and BMI. Participants were then divided into quartiles based on fecal component levels correlated with BMI, and the prevalence ratio (PR) of obesity was calculated, adjusted for confounding factors. We also analyzed the composition and diversity of gut microbiota and bacterial gene expression among the quartiles for each fecal component. Fecal glycocholic acid (GCA) showed a significant positive correlation with BMI. The PR for obesity in the highest quartile of fecal GCA was 3.30 (95% CI, 1.21-9.54), indicating a significantly higher risk of obesity compared to the lowest quartile. Gut microbiota analysis revealed significant differences in the abundance of Ruminococcaceae Incertae Sedis, Faecalibacterium, and Methanobrevibacter, with Methanobrevibacter being absent in the higher quartiles of fecal GCA. Additionally, gene expression for enzymes involved in the deconjugation of conjugated bile acids, including GCA, was downregulated in the highest quartile. Increased fecal GCA levels are positively correlated with obesity, alongside a depletion of archaea.

The Role of Bile Acid in Immune-Mediated Skin Diseases

Immune-mediated skin disorders arise from dysfunctional immune responses, instigating inflammatory dermatoses and a reduced quality of life. The complex pathogenesis likely involves genetic risks, environmental triggers and aberrant immune activation. An emerging body of evidence suggests that bile acid disturbances may critically promote immune pathology in certain skin conditions. Bile acids synthesised from cholesterol regulate nutrient metabolism and immune cell function via nuclear receptors and G protein-coupled receptors (GPCRs). Altered bile acid profiles and receptor expression have been identified in psoriasis, atopic dermatitis (AD) and autoimmune blistering diseases. Disruptions in bile acid signalling affect the inflammatory and metabolic pathways linked to these disorders. Targeting components of the bile acid axis represents a promising therapeutic strategy. This review elucidates the intricate links between bile acid homeostasis and immune dysfunction in inflammatory skin diseases, synthesising evidence that targeting bile acid pathways may unlock innovative therapeutic avenues. This study compiles clinical and experimental data revealing disrupted bile acid signalling and composition in various immune-mediated dermatoses, highlighting the emerging significance of bile acids in cutaneous immune regulation.

Species-level quantification of Faecalibacterium spp. in faeces of healthy Japanese adults

Faecalibacterium prausnitzii has been considered one of the predominant microbes in the gut microbiota of healthy human adults. Moreover, due to its beneficial metabolites and its reduced population in patients with various disorders, this organism has been regarded as one of the key gut microbes in human health. However, following recent revisions in the taxonomy of the genus Faecalibacterium and F. prausnitzii, the reported population distribution and health benefits of this species have become unclear. In the present study, the population of nine species-level taxonomic groups (hereafter referred to as species) within Faecalibacterium was quantified at the species level in the faeces of healthy Japanese adults (n=88). qPCR, combined with rpoA-based species-specific primers, showed that Faecalibacterium taiwanense had the highest detection rate (prevalence) and copy number among Faecalibacterium spp., followed by Faecalibacterium longum, Faecalibacterium duncaniae and F. prausnitzii, while the remaining five species were detected only occasionally. The population of F. duncaniae varied significantly between age groups, being higher in individuals in their 40s and 50s compared to those in their 20s (P=0.047 and 0.002, respectively). The present study indicates that F. prausnitzii is not the predominant Faecalibacterium species in the healthy Japanese adults included in the present study. Future studies will shed light on the health benefits of the dominant Faecalibacterium spp.

Gut microbiota variations in depression and anxiety: a systematic review

OBJECTIVE

The aim of this study is to investigate the characteristics of gut microbiota in depression and anxiety through a systematic review.

METHODS

Articles were searched in the PubMed, Embase, and PsycINFO databases from their inception to February 12th, 2023. Case-control studies on the characteristics of gut microbiota in depression and anxiety were included. Methodological quality assessment of included studies was performed using the Newcastle-Ottawa Scale (NOS). A qualitative synthesis was conducted to assess bacterial diversity (α- and β-diversity) and taxa abundance differences at the phylum, family, and genus levels.

RESULTS

A total of 24 articles were included in the systematic review, 20 studies were conducted in China. Our results showed that the findings of the α- and β-diversity assessments were inconsistent for both depression and anxiety. In gut microbiota composition, we found that depression and anxiety were characterized by an enrichment of pro-inflammatory bacteria and a depletion of anti-inflammatory SCFAs-producing bacteria. Specifically, Actinobacteria, Proteobacteria, Rikenellaceae, Porphyromonadaceae and Bifidobacteriaceae were more abundant in the depression group, as well as Firmicutes, Prevotellacea and Ruminococcaceae in lower abundance. In the anxiety group, the abundance of Firmicutes, Lachnospira, Faecalibacterium, Sutterella, and Butyricicoccus was lower, while the abundance of Bacteroidetes, Enterobacteriaceae, and Fusobacterium was increased.

CONCLUSIONS

The systematic review found that depression and anxiety might be characterized by an enrichment of pro-inflammatory bacteria and the depletion of anti-inflammatory SCFAs-producing bacteria. However, there were conflicting reports on the abundance of bacteria due to confounders such as diet and psychotropic medications. Further studies are strongly suggested.

CLINICAL TRIAL NUMBER

Not applicable.

Mechanistic Implications of the Mediterranean Diet in Patients With Newly Diagnosed Crohn's Disease: Multiomic Results From a Prospective Cohort

BACKGROUND & AIMS

To decipher the mechanisms underlying the protective role of the Mediterranean diet (MED) in Crohn's disease (CD), we explored the implications of adherence to MED on CD course, inflammatory markers, and microbial and metabolite composition.

METHODS

Patients with newly diagnosed CD were recruited and followed prospectively. MED adherence was assessed by repeated food frequency questionnaires (FFQs) using a predefined inflammatory bowel disease Mediterranean diet score (IBDMED score), alongside validated MED adherence screeners. Crohn's disease activity index (CDAI), C-reactive protein, fecal calprotectin, and microbial composition (16S-ribosomal RNA sequencing) were assessed each visit. Baseline serum and fecal samples were analyzed for targeted quantitative metabolomics.

RESULTS

Consecutive patients: 271 (52% men, average age 31 ± 12 years, B1 phenotype 75%). FFQs collected: 636 (range 1-5 FFQs per patient). Adherence to MED was associated with a noncomplicated CD course, and inversely correlated with CDAI, fecal calprotectin, C-reactive protein, and microbial dysbiosis index (all P < .05). Increasing adherence to MED over time correlated with reduced CDAI and inflammatory markers (P < .05). Adherence to MED correlated with a microbial cluster of commensals and short-chain fatty acid producers including Faecalibacterium, and with plant metabolites, vitamin derivatives, and amino acids. Conversely, adherence to MED inversely correlated with a cluster of oral genera, Escherichia coli and Ruminococcus gnavus, known CD-associated species, and with tryptophan metabolites, ceramides, and primary bile acids (false discovery rate < 0.2).

CONCLUSION

Adherence to MED is associated with beneficial clinical outcomes and decreased inflammatory markers. These may be driven by lower levels of primary bile acids and microbial dysbiosis and a beneficial microbial and metabolite composition. Randomized controlled trials are needed to evaluate the role of MED in CD management.

It Takes a Village: Juvenile Idiopathic Arthritis and the Microbiome

Multiple risk factors for juvenile idiopathic arthritis (JIA) influence the microbiome, and various differences in the oral and fecal microbiome have been described to date in JIA. This review summarizes what is known and discusses potential implications for future research on the microbiome in JIA.

Associations Between the Gut Microbiota and Its Related Metabolic Pathways and Uveitis: A Bidirectional Two-Sample Mendelian Randomization Study

Purpose

Some experimental reports have proposed an interaction between gut microbiota (GM) and uveitis. However, the exact association between GM and its metabolic pathways and uveitis remains unknown. This study was conducted to explore the bidirectional causal relationship between GM and its metabolic pathways and uveitis.

Methods

Summary data of the GM and its metabolic pathways and uveitis were leveraged from the Dutch Microbiome Project and the Genome-Wide Association Studies (GWAS) Catalog, respectively. We then conducted Mendelian randomization (MR) analysis to explore whether the GM and its metabolic pathways have a corresponding causal relationship with uveitis. To confirm the credibility of the findings, we utilized MR Egger, the MR-PRESSO global test, and the Cochran Q test to detect pleiotropy and heterogeneity.

Results

According to the inverse variance weighting method, the species Bacteroides faecis (odds ratio [OR] = 0.598, 95% confidence interval [CI] = 0.390–0.919, P = 0.019) and the superpathway of sulfate assimilation and cysteine biosynthesis (OR = 0.179, 95% CI = 0.038–0.843, P = 0.029) had beneficial effects on uveitis. In contrast, the genus Sutterellaceae (OR = 3.493, 95% CI = 1.121–10.879, P = 0.030); the species Parabacteroides distasonis (OR = 5.932, 95% CI = 1.321–26.635, P = 0.020), Faecalibacterium prausnitzii (OR = 4.838, 95% CI = 1.067–21.936, P = 0.040), and Bacteroides caccae (OR = 3.818, 95% CI = 1.010–14.437, P = 0.048); and the L1,2–propanediol degradation (OR = 2.084, 95% CI = 1.098–3.954, P = 0.024), galactose degradation I (Leloir pathway; OR = 3.815, 95% CI = 1.108–13.135, P = 0.033), TCA cycle VI (obligate autotrophs; OR = 2.955, 95% CI = 1.015–8.606, P = 0.046) and UMP biosynthesis (OR = 4.979, 95% CI = 1.000–24.782, P = 0.049) pathways had adverse effects on uveitis. No pleiotropy or heterogeneity was found. Leave-one-out analysis showed the reliability of the above findings.

Conclusions

Our analysis revealed a causality between certain GM species and metabolic pathways and uveitis via genetic prediction, which may provide new perspectives into the etiology and therapies of uveitis.

Translational Relevance

This study provides evidence that modulating the intestinal flora and its metabolic pathways is effective in treating uveitis.

The microenvironment in the development of MASLD-MASH-HCC and associated therapeutic in MASH-HCC

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a series of obesity-related metabolic liver diseases, ranging from relatively benign hepatic steatosis to metabolic-associated steatohepatitis (MASH). With the changes in lifestyle, its incidence and prevalence have risen to epidemic proportions globally. In recent years, an increasing amount of evidence has indicated that the hepatic microenvironment is involved in the pathophysiological processes of MASH-induced liver fibrosis and the formation of hepatocellular carcinoma (HCC). The hepatic microenvironment is composed of various parenchymal and non-parenchymal cells, which communicate with each other through various factors. In this review, we focus on the changes in hepatocytes, cholangiocytes, liver sinusoidal endothelial cells (LSECs), hepatic stellate cells (HSCs), Kupffer cells (KC), dendritic cells (DC), neutrophils, monocytes, T and B lymphocytes, natural killer cells (NK), natural killer T cells (NKT), mucosal-associated invariant T cells (MAIT), γδT cells, and gut microbiota during the progression of MASLD. Furthermore, we discuss promising therapeutic strategies targeting the microenvironment of MASLD-MASH-HCC.

Gut microbiota - bidirectional modulator: role in inflammatory bowel disease and colorectal cancer

The gut microbiota is a diverse ecosystem that significantly impacts human health and disease. This article focuses on how the gut microbiota interacts with inflammatory bowel diseases and colorectal tumors, especially through immune regulation. The gut microbiota plays a role in immune system development and regulation, while the body's immune status can also affect the composition of the microbiota. These microorganisms exert pathogenic effects or correct disease states in gastrointestinal diseases through the actions of toxins and secretions, inhibition of immune responses, DNA damage, regulation of gene expression, and protein synthesis. The microbiota and its metabolites are essential in the development and progression of inflammatory bowel diseases and colorectal tumors. The complexity and bidirectionality of this connection with tumors and inflammation might render it a new therapeutic target. Hence, we explore therapeutic strategies for the gut microbiota, highlighting the potential of probiotics and fecal microbiota transplantation to restore or adjust the microbial community. Additionally, we address the challenges and future research directions in this area concerning inflammatory bowel diseases and colorectal tumors.

Personalized Microbiome Modulation to Improve Clinical Outcomes in Pediatric Inflammatory Bowel Disease: A Multi-Omics and Interventional Approach

Inflammatory bowel disease (IBD) is a complex disorder influenced by genetic, environmental, and microbial factors, with emerging evidence highlighting the gut microbiome's role in disease pathogenesis. This study investigates the impact of microbiome-targeted interventions in pediatric IBD by integrating multi-omics analysis, including metagenomics, metabolomics, transcriptomics, and clinical biomarkers, to identify microbial dysbiosis patterns and potential therapeutic targets. A cohort of pediatric IBD patients underwent a personalized intervention involving dietary modifications, probiotic supplementation, and selective antibiotic therapy. Microbiome composition, inflammatory markers (fecal calprotectin, CRP), and disease activity scores (PCDAI/PUCAI) were assessed before and after treatment. At the 3-month follow-up, patients showed significant clinical improvement, with reduced stool frequency (p = 0.004) and improved stool consistency (p < 0.001). Symptoms such as bloating and abdominal pain decreased, while energy levels increased (p < 0.001). Dietary changes included higher fruit, meat, and dairy intake, and lower fast-food and sweets consumption (p < 0.001). Physician assessments classified 90% as "improved", reinforcing the effectiveness of personalized microbiome interventions. Microbiome-targeted interventions (diet, probiotics, and selective antibiotics) improved pediatric IBD outcomes by reducing pathogenic bacteria and increasing short-chain fatty acid (SCFA)-producing species, lowering inflammation and symptoms. Early-life factors (cesarean birth, and formula feeding) influence IBD risk. Personalized diets enhanced microbial balance. Integrating multi-omics supports precision medicine, offering microbiome-based biomarkers and reducing immunosuppressive reliance.

The Role of Beneficial Microbiota in COVID-19: Insights from Key Bacterial Genera

The COVID-19 pandemic has highlighted the need for a comprehensive understanding of the factors influencing disease severity and progression. Emerging research indicates that the human microbiota, particularly beneficial bacteria, significantly impacts immune responses and health outcomes in COVID-19 patients. While existing studies provide general insights into the relationship between the microbiota and probiotics with COVID-19, they often lack a detailed exploration of how specific bacterial taxa might be used as adjunctive treatments. This review aims to address this gap by focusing on ten key genera of beneficial bacteria, discussing their roles in COVID-19 and evaluating their potential as probiotics for prevention and treatment. The review covers the impact of these microbes on human health, their population alterations in COVID-19 patients, and their interactions with other viral infections. Among these microbes, several exhibit distinct patterns of abundance in COVID-19 patients, influencing disease outcomes and highlighting their potential roles in infection dynamics. In COVID-19 patients, populations of Akkermansia, Ruminococcus, and Roseburia are consistently reduced, while those of Faecalibacterium show a significant decline in more severe cases. Bacteroides presents varying effects depending on the species involved. Alterations in the abundance of Blautia and Lachnospiraceae are associated with increased inflammation and disease severity. Likewise, the depletion of Lachnospira and Coprococcus populations, both linked to anti-inflammatory effects, may exacerbate symptom severity. Oscillospira, though less studied, is connected to overall health and could have implications for viral infections. This review synthesizes the current understanding of these beneficial microbes to highlight the importance of maintaining a healthy microbiota to alleviate the impact of COVID-19 and contribute to the development of novel therapeutic strategies involving microbiota modulation.

Comparison of the gut microbiota in older people with and without sarcopenia: a systematic review and meta-analysis

Introduction

Sarcopenia, an age-related disorder marked by decreased skeletal muscle mass, strength, and function, is associated with negative health impacts in individuals and financial burdens on families and society. Studies have suggested that age-related alterations in gut microbiota may contribute to the development of sarcopenia in older people through the gut-muscle axis, thus modulation of gut microbiota may be a promising approach for sarcopenia treatment. However, the characteristic gut microbiota for sarcopenia has not been consistent across studies. Therefore, the aim of this study was to compare the diversity and compositional differences in the gut microbiota of older people with and without sarcopenia, and to identify gut microbiota biomarkers with therapeutic potential for sarcopenia.

Methods

The PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, and Wanfang Database were searched studies about the gut microbiota characteristics in older people with sarcopenia. The quality of included articles was assessed by the Newcastle-Ottawa Scale (NOS). Weighted standardized mean differences (SMDs) and 95% confidence intervals (CIs) for α-diversity index were estimated using a random effects model. Qualitative synthesis was conducted for β-diversity and the correlation between gut microbiota and muscle parameters. The relative abundance of the gut microbiota was analyzed quantitatively and qualitatively, respectively.

Results

Pooled estimates showed that α-diversity was significantly lower in older people with sarcopenia (SMD: -0.41, 95% CI: -0.57 to -0.26, I²: 71%, P < 0.00001). The findings of β-diversity varied across included studies. In addition, our study identified gut microbiota showing a potential and negative correlation with sarcopenia, such as Prevotella, Slackia, Agathobacter, Alloprevotella, Prevotella copri, Prevotellaceae sp., Bacteroides coprophilus, Mitsuokella multacida, Bacteroides massiliensis, Bacteroides coprocola Conversely, a potential and positive correlation was observed with opportunistic pathogens like Escherichia-Shigella, Eggerthella, Eggerthella lenta and Collinsella aerofaciens.

Discussion

This study showed that α-diversity is decreased in sarcopenia, probably predominantly due to diminished richness rather than evenness. In addition, although findings of β-diversity varied across included studies, the overall trend toward a decrease in SCFAs-producing bacteria and an increase in conditionally pathogenic bacteria. This study provides new ideas for targeting the gut microbiota for the prevention and treatment of sarcopenia.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/view/CRD42024573090, identifier CRD42024573090.

Obesity: pathophysiology and therapeutic interventions

Over the past few decades, obesity has transitioned from a localized health concern to a pressing global public health crisis affecting over 650 million adults globally, as documented by WHO epidemiological surveys. As a chronic metabolic disorder characterized by pathological adipose tissue expansion, chronic inflammation, and neuroendocrine dysregulation that disrupts systemic homeostasis and impairs physiological functions, obesity is rarely an isolated condition; rather, it is frequently complicated by severe comorbidities that collectively elevate mortality risks. Despite advances in nutritional science and public health initiatives, sustained weight management success rates and prevention in obesity remain limited, underscoring its recognition as a multifactorial disease influenced by genetic, environmental, and behavioral determinants. Notably, the escalating prevalence of obesity and its earlier onset in younger populations have intensified the urgency to develop novel therapeutic agents that simultaneously ensure efficacy and safety. This review aims to elucidate the pathophysiological mechanisms underlying obesity, analyze its major complications-including type 2 diabetes mellitus (T2DM), cardiovascular diseases (CVD), non-alcoholic fatty liver disease (NAFLD), obesity-related respiratory disorders, obesity-related nephropathy (ORN), musculoskeletal impairments, malignancies, and psychological comorbidities-and critically evaluate current anti-obesity strategies. Particular emphasis is placed on emerging pharmacological interventions, exemplified by plant-derived natural compounds such as berberine (BBR), with a focus on their molecular mechanisms, clinical efficacy, and therapeutic advantages. By integrating mechanistic insights with clinical evidence, this review seeks to provide innovative perspectives for developing safe, accessible, and effective obesity treatments.

Balancing Promise and Uncertainty: PPAR Agonists in IBD Therapy

PPARγ/β/δ agonists have emerged as potential therapeutic agents for inflammatory bowel disease (IBD) due to their immunomodulatory effects and ability to influence gut microbiota composition. Li et al. investigated their impact on dextran sodium sulfate (DSS)-induced colitis, demonstrating reduced colonic inflammation and favorable microbiota shifts. However, methodological considerations, including the limitations of DSS-induced colitis as a chronic disease model and the absence of long-term follow-up, warrant further scrutiny. Additionally, alternative therapeutic strategies such as probiotics and dietary interventions have exhibited similar microbiota-modulating and anti-inflammatory benefits, necessitating comparative efficacy studies. Concerns regarding the systemic effects and safety profile of PPAR agonists also require attention, particularly in patients with metabolic comorbidities. To optimize clinical translation, future research should focus on chronic colitis models, human trials, and precision medicine approaches to tailor PPAR-targeted therapies. A comprehensive evaluation integrating host metabolism, immune regulation, and microbiota interactions will be essential to establish their role in IBD management.

Human gut microbiota adaptation to high-altitude exposure: longitudinal analysis over acute and prolonged periods

This study investigated the longitudinal effects of acute (7-day) and prolonged (3-month) high-altitude exposure on gut microbiota in healthy adult males, addressing the limited data available in human populations. A cohort of 406 healthy adult males was followed, and fecal samples were collected at three time points: baseline at 800 m (406 samples), 7 days after ascending to 4,500 m (406 samples), and 2 weeks post-return to 800 m following 3 months at high altitude (186 samples). High-throughput 16S ribosomal DNA sequencing was employed to analyze microbiota composition and diversity. Results revealed significant changes in alpha- and beta-diversity, with acute high-altitude exposure inducing more pronounced effects compared to prolonged exposure. Specifically, acute exposure increased opportunistic pathogens (Ruminococcus and Oscillibacter) but decreased beneficial short-chain fatty acid producers (Faecalibacterium and Bifidobacterium). Notably, these changes in microbiota persisted even after returning to low altitude, indicating long-term remodeling. Functional analyses revealed substantial changes in metabolic pathways, suggesting microbiota-driven adaptations to energy utilization under high-altitude hypoxic conditions. In summary, acute high-altitude exposure caused dramatic changes in gut microbiota, while prolonged exposure led to structural and functional reshaping. These findings enhance our understanding of how high-altitude environments reshape gut microbiota.

IMPORTANCE

This study is the first to investigate the impact of high-altitude exposure on gut microbiota adaptation in a large-scale longitudinal cohort. It seeks to enhance understanding of how high-altitude environments reshape gut microbiota. Acute exposure to high altitude significantly affected both α-diversity and β-diversity of gut microbiota, with acute exposure causing more pronounced changes than prolonged adaptation, indicating temporary disruptions in microbial communities. Notable shifts in microbial abundance were observed, including increased levels of genera linked to hypoxic stress (e.g., Gemmiger, Ruminococcus, and Parabacteroides) and decreased levels of beneficial bacteria (e.g., Faecalibacterium, Roseburia, and Bifidobacterium), suggesting possible adverse health effects. Functional analysis indicated changes in metabolism-related pathways post-exposure, supporting the idea that high-altitude adaptations involve metabolic adjustments for energy management. These findings enhance understanding of high-altitude physiology, illustrating the role of gut microbiota in hypoxic health.

Faecalibacterium Diversity in the Gut Microbiome of Crohn's Disease Patients

Faecalibacterium has recently garnered attention for its potential health implications. To better understand its role, we developed and assessed real-time PCR assays for detecting and quantifying various Faecalibacterium species in human stool samples from both healthy individuals and Crohn's disease patients, either in flare or remission. The assays targeted the Microbial Anti-inflammatory Molecule (MAM) genes, which encode MAM proteins. These assays demonstrated 100% species-specificity using strains from six Faecalibacterium species: Faecalibacterium prausnitzii, Faecalibacterium taiwanense, Faecalibacterium duncaniae, Faecalibacterium longum, Faecalibacterium hattori, and Faecalibacterium CNCM4541. They also showed high sensitivity with detection limits of 10^5 bacteria per gram of sample. In healthy individuals, the different Faecalibacterium species varied in abundance. F. taiwanense, F. duncaniae, and F. longum were the most prevalent, around 10^10 bacteria/g of stool. In contrast, F. hattori and CNCM4541 were less abundant, with 10^7 bacteria/g. Despite its low abundance, F. hattori was present in all healthy subjects, while CNCM4541 was detected in only 50% of them. Notably, F. taiwanense, F. duncaniae, and F. longum were found in all healthy individuals. In Crohn's disease patients, both in flare and remission, a decrease in Faecalibacterium species was observed, with no recovery in remission. The most abundant species in Crohn's disease patients were F. prausnitzii and F. duncaniae, around 10^7 bacteria/g, while F. longum, F. hattori, and F. taiwanense were present at lower levels (10^6 bacteria/g), and CNCM4541 was no longer detected. Interestingly, F. prausnitzii showed a smaller decrease in abundance compared with other species. Moreover, F. prausnitzii was significantly more prevalent in patients in remission than in those in flare, suggesting that it may be more resistant to inflammation. These findings highlight the importance of accurately characterizing and quantifying Faecalibacterium species to better understand their role in health and disease.

Faecal microbiota transplantation in Crohn's disease: an Australian randomised placebo-controlled trial protocol

INTRODUCTION

The enteric microbiota drives inflammation in Crohn's disease. Yet, there are no placebo controlled trials evaluating the efficacy and safety of faecal microbiota transplantation (FMT) in inducing and maintaining remission in patients with active Crohn's disease. The Microbial Restoration (MIRO) study aims to establish this evidence.

METHODS AND ANALYSIS

At two specialist inflammatory bowel disease centres, 120 enrolled patients will have a 3-week period of diet optimisation (removal of ultra-processed foods) together with a 7-day course of antibiotics (to facilitate subsequent FMT engraftment). Patients will then be stratified to upper gut (for disease proximal to the splenic flexure) or lower gut (distal to the splenic flexure) disease. Patients will then be randomised in a 2:1 ratio to receive anaerobically prepared stool or placebo for 8 weeks either by gastroscopy, or colonoscopy and enemas. Clinical response at 8 weeks (Crohn's Disease Activity Index (CDAI) reduction ≥100 points or to <150 points) is the primary outcome measure. Non-responders to placebo and partial responders to FMT (CDAI decrease <100 but >70) receive FMT for weeks 8-16.Patients achieving clinical response from FMT after 8 or 16 weeks will be randomised in a 1:1 ratio to either a 44-week maintenance phase of FMT or placebo. Patients will receive FMT from one donor throughout the study.The MIRO study will establish whether FMT is an effective and safe therapy to induce and maintain remission in patients with active Crohn's disease.

ETHICS AND DISSEMINATION

Ethical approval has been received by the St Vincent's Hospital Melbourne Human Research Ethics Committee (HREC-A 084/21). The results will be disseminated in peer-reviewed journals and presented at international conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT04970446; Registered on 20 July 2021.

Probiotic Lactocaseibacillus casei NK1 Enhances Growth and Gut Microbiota in Avian Pathogenic Escherichia coli Challenged Broilers

The present study was conducted to assess the efficacy of Laboratory-Isolated Lactocaseibacillus casei NK1 (Lc. NK1) in broilers hypothesizing that, Lc. NK1 supplementation will enhance growth performance, modulate the gut microbiome, and reduce fecal pathogenic Escherichia coli in broilers. The experiment spanned 35 days where 60 one-day-old broiler chicks were randomly assigned to four treatment groups (n = 15); control-group with no treatment (NC), APEC (challenged with E. coli only), CProb (received commercial probiotics), and LNK1 (treated with Lc. NK1). The APEC, CProb, and LNK1 groups were infected with E. coli O78 strain at 11 days of age. Growth performance analysis revealed that the LNK1 group by day 35 gained body weight similar to the CProb group, with both groups significantly outperforming the APEC group (p < 0.001). Both the LNK1 and CProp groups exhibited similar reduction in E. coli while increasing Lactobacillus colorizations in the cloacal swabs from day 21 to 35 of age (p > 0.05). Metagenomic analysis using 16S rRNA sequencing showed that the LNK1 group maintained a diverse and balanced gut microbiota, characterized by increased Firmicutes and reduced Proteobacteria. In contrast, the APEC group exhibited reduced diversity and dominance of Escherichia-Shigella (p < 0.001). These findings suggest Lc. NK1 could be a promising probiotic for enhancing gut health and growth performance in broilers, even under pathogenic challenges, offering a potential alternative to antibiotics in poultry production.

Intestinal Microbiota Contributes to the Development of Cardiovascular Inflammation and Vasculitis in Mice

BACKGROUND

Alterations in the intestinal microbiota contribute to the pathogenesis of various cardiovascular disorders, but how they affect the development of Kawasaki disease (KD) an acute pediatric vasculitis, remains unclear.

METHODS

We used the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis to assess the contribution of the intestinal microbiota to the development of vascular inflammation. We evaluated the severity of vasculitis in microbiota-depleted mice. 16S rRNA gene sequencing was used to characterize the fecal microbiome composition of LCWE-injected mice. Some groups of mice were orally treated with selected live or pasteurized bacteria, short-chain fatty acids, or Amuc_1100, the Toll-like receptor 2 signaling outer membrane protein from Akkermansia muciniphila, and their impact on vasculitis development was assessed.

RESULTS

We report that depleting the gut microbiota reduces the development of cardiovascular inflammation in a murine model mimicking KD vasculitis. The development of cardiovascular lesions was associated with alterations in the intestinal microbiota composition and, notably, a decreased abundance of Akkermansia muciniphila and Faecalibacterium prausnitzii. Oral supplementation with either of these live or pasteurized individual bacteria or with short-chain fatty acids produced by them attenuated cardiovascular inflammation, as reflected by decreased local immune cell infiltrations. Treatment with Amuc_1100 also reduced the severity of vascular inflammation.

CONCLUSIONS

This study reveals an underappreciated gut microbiota-cardiovascular inflammation axis in KD vasculitis pathogenesis and identifies specific intestinal commensals that regulate vasculitis in mice by producing metabolites or via extracellular proteins capable of enhancing and supporting gut barrier function.

A Cascade of Microbiota-Leaky Gut-Inflammation- Is it a Key Player in Metabolic Disorders?

PURPOSE OF REVIEW

This review addresses critical gaps in knowledge and provides a literature overview of the molecular pathways connecting gut microbiota dysbiosis to increased intestinal permeability (commonly referred to as "leaky gut") and its contribution to metabolic disorders. Restoring a healthy gut microbiota holds significant potential for enhancing intestinal barrier function and metabolic health. These interventions offer promising therapeutic avenues for addressing leaky gut and its associated pathologies in metabolic syndrome.

RECENT FINDINGS

In metabolic disorders such as obesity and type 2 diabetes (T2D), beneficial microbes such as those producing short-chain fatty acids (SCFAs) and other key metabolites like taurine, spermidine, glutamine, and indole derivatives are reduced. Concurrently, microbes that degrade toxic metabolites such as ethanolamine also decline, while proinflammatory, lipopolysaccharide (LPS)-enriched microbes increase. These microbial shifts place a higher burden on intestinal epithelial cells, which are in closest proximity to the gut lumen, inducing detrimental changes that compromise the structural and functional integrity of the intestinal barrier. Such changes include exacerbation of tight junction protein (TJP)s dysfunction, particularly through mechanisms such as destabilization of zona occludens (Zo)-1 mRNA or post-translational modifications. Emerging therapeutic strategies including ketogenic and Mediterranean diets, as well as probiotics, prebiotics, synbiotics, and postbiotics have demonstrated efficacy in restoring beneficial microbial populations, enhancing TJP expression and function, supporting gut barrier integrity, reducing leaky gut and inflammation, and ultimately improving metabolic disorders. This review summarizes the mechanisms by which gut microbiota contribute to the development of leaky gut and inflammation associated with metabolic syndrome. It also explores strategies for restoring gut microbiota balance and functionality by promoting beneficial microbes, increasing the production of beneficial metabolites, clearing toxic metabolites, and reducing the proportion of proinflammatory microbes. These approaches can alleviate the burden on intestinal epithelial cells, reduce leaky gut and inflammation, and improve metabolic health.

Lineage-specific microbial protein prediction enables large-scale exploration of protein ecology within the human gut

Microbes use a range of genetic codes and gene structures, yet these are often ignored during metagenomic analysis. This causes spurious protein predictions, preventing functional assignment which limits our understanding of ecosystems. To resolve this, we developed a lineage-specific gene prediction approach that uses the correct genetic code based on the taxonomic assignment of genetic fragments, removes incomplete protein predictions, and optimises prediction of small proteins. Applied to 9634 metagenomes and 3594 genomes from the human gut, this approach increased the landscape of captured expressed microbial proteins by 78.9%, including previously hidden functional groups. Optimised small protein prediction captured 3,772,658 small protein clusters, which form an improved microbial protein catalogue of the human gut (MiProGut). To enable the ecological study of a protein's prevalence and association with host parameters, we developed InvestiGUT, a tool which integrates both the protein sequences and sample metadata. Accurate prediction of proteins is critical to providing a functional understanding of microbiomes, enhancing our ability to study interactions between microbes and hosts.

Faecalibacterium prausnitzii-derived outer membrane vesicles reprogram gut microbiota metabolism to alleviate Porcine Epidemic Diarrhea Virus infection

BACKGROUND

The Porcine Epidemic Diarrhea Virus (PEDV) is one of the major challenges facing the global pig farming industry, and vaccines and treatments have proven difficult in controlling its spread. Faecalibacterium prausnitzii (F.prausnitzii), a key commensal bacterium in the gut, has been recognized as a promising candidate for next-generation probiotics due to its potential wide-ranging health benefits. A decrease in F.prausnitzii abundance has been associated with certain viral infections, suggesting its potential application in preventing intestinal viral infections. In this study, we utilized a piglet model to examine the potential role of F.prausnitzii in PEDV infections.

RESULTS

A piglet model of PEDV infection was established and supplemented with F.prausnitzii, revealing that F.prausnitzii mitigated PEDV infection. Further studies found that outer membrane vesicles (OMVs) are the main functional components of F.prausnitzii, and proteomics, untargeted metabolomics, and small RNA-seq were used to analyze the composition of OMVs. Exhaustion of the gut microbiota demonstrated that the function of Fp. OMVs relies on the presence of the gut microbiota. Additionally, metagenomic analysis indicated that Fp. OMVs altered the gut microbiota composition, enhancing the abundance of Faecalibacterium prausnitzii, Prevotellamassilia timonensis, and Limosilactobacillus reuteri. Untargeted metabolomics analysis showed that Fp. OMVs increased phosphatidylcholine (PC) levels, with PC identified as a key metabolite in alleviating PEDV infection. Single-cell sequencing revealed that PC altered the relative abundance of intestinal cells, increased the number of intestinal epithelial cells, and reduced necroptosis in target cells. PC treatment in infected IPEC-J2 and Vero cells alleviated necroptosis and reduced the activation of the RIPK1-RIPK3-MLKL signaling axis, thereby improving PEDV infection.

CONCLUSION

F.prausnitzii and its OMVs play a critical role in mitigating PEDV infections. These findings provide a promising strategy to ameliorate PEDV infection in piglets. Video Abstract.