Gut Microbiota Profile in Pediatric Patients With Inflammatory Bowel Disease: A Systematic Review

Bacteroides uniformis ameliorates pro-inflammatory diet-exacerbated colitis by targeting endoplasmic reticulum stress-mediated ferroptosis

INTRODUCTION

A pro-inflammatory diet is positively associated with the risk and progression of inflammatory bowel diseases (IBD). Recently, ferroptosis has been observed in patients with different dietary patterns-associated intestinal inflammation, while the mechanisms underlying the effects of a pro-inflammatory diet and whether it mediates ferroptosis are unknown.

OBJECTIVES

This study aims to elucidate the mechanisms underlying pro-inflammatory diet-mediated colitis and explore potential intervention strategies.

METHODS

Mice were fed a dietary inflammatory index-based pro-inflammatory diet for 12 weeks. Subsequently, colitis was chemically induced using 2.5 % dextran sulfate sodium. The body weight, pathological score, immune response and mucosal barrier function were evaluated to assess intestinal inflammation. Intestine tissue transcriptomics, fecal microbiome analysis and serum metabolomics were applied to identify diet-microbe-host interactions. Additionally, the dietary inflammatory index (DII) scores and intestinal specimens of 32 patients with Crohn's disease were evaluated. The biological functions of Bacteroides uniformis were observed in vitro and in vivo.

RESULTS

Pro-inflammatory diet induces low-grade intestinal inflammation in mice and exacerbates colitis by activating glutathione peroxidase 4-associated ferroptosis in the endoplasmic reticulum stress-mediated pathway. These effects are reversed by ferrostatin-1 treatment. Additionally, the pro-inflammatory diet triggers colitis by modulating the gut microbiota and metabolites. Notably, supplementation with B. uniformis improves the pro-inflammatory diet-aggravated colitis by inhibiting endoplasmic reticulum stress-mediated ferroptosis. Moreover, B. uniformis is non-enterotoxigenic and non-enteroinvasive in co-cultures with intestinal epithelial cells.

CONCLUSIONS

Pro-inflammatory diet drives colitis by targeting endoplasmic reticulum stress-mediated ferroptosis, possibly in a gut microbiota-dependent manner. Pro-inflammatory diet restriction and microbial-based therapies may be effective strategies for preventing and treating IBD.

Bifidogenic Effect of Human Milk Oligosaccharides on Pediatric IBD Fecal Microbiota

The prevalence of pediatric inflammatory bowel disease (pIBD) has been increasing over the last two decades. Yet, treatment strategies are still limited, in part due to the multifactorial nature of the disease and the complex interplay between genetic, environmental, dietary, immune, and gut microbial factors in its etiology. With their direct and indirect anti-inflammatory properties, human milk oligosaccharides (HMOs) are a promising treatment and management strategy for IBD. However, to date there are no insights into how HMOs may affect pIBD microbiota. Here, we compared the effects of 2'fucosyllactose (2'FL), difucosyllactose (DFL), 3'sialyllactose (3'SL), and blends thereof with fructooligosaccharide (FOS) on microbiota functionality (short- and branched-chain fatty acids, pH, and gas production) and composition (quantitative shallow shotgun sequencing) using fecal material from eight different pediatric Crohn's disease patients inoculated in the SIFR® technology. In general, all HMO treatments significantly increased total short-chain fatty acid production when compared with FOS, despite equal gas production. We found that 2'FL, either alone or in combination with DFL and 3'SL, exhibited a strong acetogenic and propiogenic effect, and 3'SL an acetogenic effect that surpassed the effects observed with FOS. No differences in overall community diversity between HMO- and FOS-treated pIBD microbiota were observed. There was, however, a stronger bifidogenic effect of 2'FL, 3'SL, 2'FL/DFL, and 2'FL/DFL + 3'SL when compared with FOS. In general, 3'SL and HMO blends enriched a broader species profile, including taxa with potentially anti-inflammatory properties, such as Faecalibacterium prausnitzii and Blautia species. This study suggests HMOs as a promising strategy to beneficially alter the gut microbial profile in pIBD.

A Novel Microbial Dysbiosis Index and Intestinal Microbiota-Associated Markers as Tools of Precision Medicine in Inflammatory Bowel Disease Paediatric Patients

Recent evidence indicates that the gut microbiota (GM) has a significant impact on the inflammatory bowel disease (IBD) progression. Our aim was to investigate the GM profiles, the Microbial Dysbiosis Index (MDI) and the intestinal microbiota-associated markers in relation to IBD clinical characteristics and disease state. We performed 16S rRNA metataxonomy on both stools and ileal biopsies, metabolic dysbiosis tests on urine and intestinal permeability and mucosal immunity activation tests on the stools of 35 IBD paediatric patients. On the GM profile, we assigned the MDI to each patient. In the statistical analyses, the MDI was correlated with clinical parameters and intestinal microbial-associated markers. In IBD patients with high MDI, Gemellaceae and Enterobacteriaceae were increased in stools, and Fusobacterium, Haemophilus and Veillonella were increased in ileal biopsies. Ruminococcaceae and WAL_1855D were enriched in active disease condition; the last one was also positively correlated to MDI. Furthermore, the MDI results correlated with PUCAI and Matts scores in ulcerative colitis patients (UC). Finally, in our patients, we detected metabolic dysbiosis, intestinal permeability and mucosal immunity activation. In conclusion, the MDI showed a strong association with both severity and activity of IBD and a positive correlation with clinical scores, especially in UC. Thus, this evidence could be a useful tool for the diagnosis and prognosis of IBD.

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

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

Familial clustering of dysbiotic oral and fecal microbiomes in juvenile dermatomyositis

Juvenile dermatomyositis (JDM) is a rare immune-mediated disease of childhood with putative links to microbial exposures. In this multi-center, prospective, observational cohort study, we evaluated whether JDM is associated with discrete oral and gut microbiome signatures. We generated 16S rRNA sequencing data from fecal, saliva, supragingival, and subgingival plaque samples from JDM probands (n = 28). To control for genetic and environmental determinants of microbiome community structure, we also profiled microbiomes of unaffected family members (n = 27 siblings, n = 26 mothers, and n = 17 fathers). Sample type (oral-vs-fecal) and nuclear family unit were the predominant variables explaining variance in microbiome diversity, more so than having a diagnosis of JDM. The oral and gut microbiomes of JDM probands were more similar to their own unaffected siblings than they were to the microbiomes of other JDM probands. In a sibling-paired within-family analysis, several potentially immunomodulatory bacterial taxa were differentially abundant in the microbiomes of JDM probands compared to their unaffected siblings, including Faecalibacterium (gut) and Streptococcus (oral cavity). While microbiome features of JDM are often shared by unaffected family members, the loss or gain of specific fecal and oral bacteria may play a role in disease pathogenesis or be secondary to immune dysfunction in susceptible individuals.

Spatial features of skip lesions in Crohn's disease

Skip lesions are an enigmatic spatial feature characterizing Crohn's disease (CD). They comprise inflamed and adjacent non-inflamed tissue sections with a clear demarcation. Currently, spatial features of the human gastrointestinal (GI) system lack clarity regarding the organization of microbes, mucus, tissue, and host cells during inflammation. New technologies with multiplexing abilities and innovative approaches provide ways of examining the spatial organization of inflamed and non-inflamed tissues in CD, which may open new avenues for diagnosis, prognosis, and treatment. In this review, we present evidence of the relevance of spatial context in patients with CD and the methods and ideas recently published in studies of spatiality during inflammation. With this review, we aim to provide inspiration for further research to address existing gaps.

The impact of intermittent fasting on gut microbiota: a systematic review of human studies

Background

Intermittent fasting (IF) has gained popularity in interventions targeting overweight, obesity and metabolic syndrome. IF may affect the gut microbiome composition and therefore have various effects on gut microbiome mediated functions in humans. Research on the effects of IF on human gut microbiome is limited. Therefore, the objective of this systematic review was to determine how different types of IF affect the human gut microbiome.

Methods

A literature search was conducted for studies investigating the association of different types of IF and gut microbiota richness, alpha and beta diversity, and composition in human subjects. Databases included Cochrane Library (RRID:SCR_013000), PubMed (RRID:SCR_004846), Scopus (RRID:SCR_022559) and Web of Science (RRID:SCR_022706). A total of 1,332 studies were retrieved, of which 940 remained after removing duplicates. Ultimately, a total of 8 studies were included in the review. The included studies were randomized controlled trials, quasi-experimental studies and pilot studies implementing an IF intervention (time-restricted eating, alternate day fasting or 5:2 diet) in healthy subjects or subjects with any disease.

Results

Most studies found an association between IF and gut microbiota richness, diversity and compositional changes. There was heterogeneity in the results, and bacteria which were found to be statistically significantly affected by IF varied widely depending on the study.

Conclusion

The findings in this systematic review suggest that IF influences gut microbiota. It seems possible that IF can improve richness and alpha diversity. Due to the substantial heterogeneity of the results, more research is required to validate these findings and clarify whether the compositional changes might be beneficial to human health.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021241619.

Early life exposure to broccoli sprouts confers stronger protection against enterocolitis development in an immunological mouse model of inflammatory bowel disease

IMPORTANCE

To our knowledge, IL-10-KO mice have not previously been used to investigate the interactions of host, microbiota, and broccoli, broccoli sprouts, or broccoli bioactives in resolving symptoms of CD. We showed that a diet containing 10% raw broccoli sprouts increased the plasma concentration of the anti-inflammatory compound sulforaphane and protected mice to varying degrees against disease symptoms, including weight loss or stagnation, fecal blood, and diarrhea. Younger mice responded more strongly to the diet, further reducing symptoms, as well as increased gut bacterial richness, increased bacterial community similarity to each other, and more location-specific communities than older mice on the diet intervention. Crohn's disease disrupts the lives of patients and requires people to alter dietary and lifestyle habits to manage symptoms. The current medical treatment is expensive with significant side effects, and a dietary intervention represents an affordable, accessible, and simple strategy to reduce the burden of symptoms.

Candida spp. in Human Intestinal Health and Disease: More than a Gut Feeling

Fungi are an essential part of the normal collection of intestinal microorganisms, even though their collective abundance comprises only 0.1-1% of all fecal microbes. The composition and role of the fungal population is often studied in relation to early-life microbial colonization and development of the (mucosal) immune system. The genus Candida is frequently described as one of the most abundant genera, and altered fungal compositions (including elevated abundance of Candida spp.) have been linked with intestinal diseases such as inflammatory bowel disease and irritable bowel syndrome. These studies are performed using both culture-dependent and genomic (metabarcoding) techniques. In this review, we aimed to summarize existing data on intestinal Candida spp. colonization in relation to intestinal disease and provide a brief overview of the biological and technical challenges in this field, including the recently described role of sub-species strain variation of intestinal Candida albicans. Together, the evidence for a contributing role of Candida spp. in pediatric and adult intestinal disease is quickly expanding, even though technical and biological challenges may limit full understanding of host-microbe interactions.

Gut microbiome, metabolome, host immunity associated with inflammatory bowel disease and intervention of fecal microbiota transplantation

Gut dysbiosis has been associated with inflammatory bowel disease (IBD), one of the most common gastrointestinal diseases. The microbial communities play essential roles in host physiology, with profound effects on immune homeostasis, directly or via their metabolites and/or components. There are increasing clinical trials applying fecal microbiota transplantation (FMT) with Crohn's disease (CD) and ulcerative colitis (UC). The restoration of dysbiotic gut microbiome is considered as one of the mechanisms of FMT therapy. In this work, latest advances in the alterations in gut microbiome and metabolome features in IBD patients and experimental mechanistic understanding on their contribution to the immune dysfunction were reviewed. Then, the therapeutic outcomes of FMT on IBD were summarized based on clinical remission, endoscopic remission and histological remission of 27 clinical trials retrieved from PubMed which have been registered on ClinicalTrials.gov with the results been published in the past 10 years. Although FMT is established as an effective therapy for both subtypes of IBD, the promising outcomes are not always achieved. Among the 27 studies, only 11 studies performed gut microbiome profiling, 5 reported immune response alterations and 3 carried out metabolome analysis. Generally, FMT partially restored typical changes in IBD, resulted in increased α-diversity and species richness in responders and similar but less pronounced shifts of patient microbial and metabolomics profiles toward donor profiles. Measurements of immune responses to FMT mainly focused on T cells and revealed divergent effects on pro-/anti-inflammatory functions. The very limited information and the extremely confounding factors in the designs of the FMT trials significantly hindered a reasonable conclusion on the mechanistic involvement of gut microbiota and metabolites in clinical outcomes and an analysis of the inconsistencies.

Evolution of a Pathogenic Microbiome

The process of microbiome development arguably begins before birth. Vertical transmission of bacteria from the mother to the infant is a keystone event in microbiome development. Subsequent to birth, the developing microbiome is vulnerable to influence from a wide range of factors. Additionally, the microbiome can influence the health and development of the host infant. This intricate interaction of the gastrointestinal microbiome and the host has been described as both symbiotic and dysbiotic. Defining these terms, a symbiotic microbiome is where the microbiome and host provide mutual benefit to each other. A pathogenic microbiome, or more precisely a gastrointestinal microbiome associated with disease, is increasing described as dysbiotic. This review seeks to investigate the factors that contribute to evolving a disease-causing or 'dysbiotic' microbiome. This review covers the development of the gastrointestinal microbiome in infants, the interaction of the microbiome with the host, and its contribution to host immunity and investigates specific features of the gastrointestinal microbiome that are associated with disease.

Multi-Omics Analysis Reveals Age-Related Microbial and Metabolite Alterations in Non-Human Primates

Aging is a systemic physiological degenerative process, with alterations in gut microbiota and host metabolism. However, due to the interference of multiple confounding factors, aging-associated molecular characteristics have not been elucidated completely. Therefore, based on 16S ribosomal RNA (rRNA) gene sequencing and non-targeted metabolomic detection, our study systematically analyzed the composition and function of the gut microbiome, serum, and fecal metabolome of 36 male rhesus monkeys spanning from 3 to 26 years old, which completely covers juvenile, adult, and old stages. We observed significant correlations between 41 gut genera and age. Moreover, 86 fecal and 49 serum metabolites exhibited significant age-related correlations, primarily categorized into lipids and lipid-like molecules, organic oxygen compounds, organic acids and derivatives, and organoheterocyclic compounds. Further results suggested that aging is associated with significant downregulation of various amino acids constituting proteins, elevation of lipids, particularly saturated fatty acids, and steroids. Additionally, age-dependent changes were observed in multiple immune-regulatory molecules, antioxidant stress metabolites, and neurotransmitters. Notably, multiple age-dependent genera showed strong correlations in these changes. Together, our results provided new evidence for changing characteristics of gut microbes and host metabolism during aging. However, more research is needed in the future to verify our findings.

MetaTransformer: deep metagenomic sequencing read classification using self-attention models

Deep learning has emerged as a paradigm that revolutionizes numerous domains of scientific research. Transformers have been utilized in language modeling outperforming previous approaches. Therefore, the utilization of deep learning as a tool for analyzing the genomic sequences is promising, yielding convincing results in fields such as motif identification and variant calling. DeepMicrobes, a machine learning-based classifier, has recently been introduced for taxonomic prediction at species and genus level. However, it relies on complex models based on bidirectional long short-term memory cells resulting in slow runtimes and excessive memory requirements, hampering its effective usability. We present MetaTransformer, a self-attention-based deep learning metagenomic analysis tool. Our transformer-encoder-based models enable efficient parallelization while outperforming DeepMicrobes in terms of species and genus classification abilities. Furthermore, we investigate approaches to reduce memory consumption and boost performance using different embedding schemes. As a result, we are able to achieve 2× to 5× speedup for inference compared to DeepMicrobes while keeping a significantly smaller memory footprint. MetaTransformer can be trained in 9 hours for genus and 16 hours for species prediction. Our results demonstrate performance improvements due to self-attention models and the impact of embedding schemes in deep learning on metagenomic sequencing data.

Identifying Microbiome Dynamics in Pediatric IBD: More than a Family Matter

BACKGROUND

Pediatric inflammatory bowel disease (IBD) is a chronic inflammatory intestinal disease that affects both children and adolescents. Symptoms can significantly affect a child's growth, development, and quality of life, making early diagnosis and effective management crucial. This study focuses on treatment-naïve pediatric IBD patients and their immediate families to identify the role of the microbiome in disease onset.

METHODS

Nine families with pediatric IBD were recruited, comprising seven drug-naïve Crohn's disease (CD) patients and two drug-naïve ulcerative colitis (UC) patients, as well as twenty-four healthy siblings/parents. Fecal samples were collected for 16S ribosomal RNA gene sequencing and bioinformatics analysis.

RESULTS

We identified patterns of dysbiosis and hallmark microbial taxa among patients who shared ethnic, habitual, and dietary traits with themselves and their families. In addition, we examined the impact of the disease on specific microbial taxa and how these could serve as potential biomarkers for early detection.

CONCLUSIONS

Our results suggest a potential role of maternal factors in the establishment and modulation of the early life microbiome, consistent with the current literature, which may have implications for understanding the etiology and progression of IBD.

Microbiome and Its Dysbiosis in Inborn Errors of Immunity

Inborn errors of immunity (IEI) can present with infections, autoimmunity, lymphoproliferation, granulomas, and malignancy. IEIs are due to genetic abnormalities that disrupt normal host-immune response or immune regulation. The microbiome appears essential for maintaining host immunity, especially in patients with a defective immune system. Altered gut microbiota in patients with IEI can lead to clinical symptoms. Microbial dysbiosis is the consequence of an increase in pro-inflammatory bacteria or a reduction in anti-inflammatory bacteria. However, functional and compositional differences in microbiota are also involved. Dysbiosis and a reduced alpha-diversity are well documented, particularly in conditions like common variable immunodeficiency. Deranged microbiota is also seen in Wiskott–Aldrich syndrome, severe combined immunodeficiency, chronic granulomatous disease, selective immunoglobulin-A deficiency, Hyper IgE syndrome (HIGES), X-linked lymphoproliferative disease-2, immunodysregulation, polyendocrinopathy, enteropathy, x-linked syndrome, and defects of IL10 signalling. Distinct gastrointestinal, respiratory, and cutaneous symptoms linked to dysbiosis are seen in several IEIs, emphasizing the importance of microbiome identification. In this study, we discuss the processes that maintain immunological homeostasis between commensals and the host and the disruptions thereof in patients with IEIs. As the connection between microbiota, host immunity, and infectious illnesses is better understood, microbiota manipulation as a treatment strategy or infection prevention method would be more readily employed. Therefore, optimal prebiotics, probiotics, postbiotics, and fecal microbial transplantation can be promising strategies to restore the microbiota and decrease disease pathology in patients with IEIs.

Targeting pathophysiological changes using biomaterials-based drug delivery systems: A key to managing inflammatory bowel disease

Inflammatory bowel disease (IBD) is a gastrointestinal disorder, affecting about several million people worldwide. Current treatments fail to adequately control some clinical symptoms in IBD patients, which can adversely impact the patient's quality of life. Hence, the development of new treatments for IBD is needed. Due to their unique properties such as biocompatibility and sustained release of a drug, biomaterials-based drug delivery systems can be regarded as promising candidates for IBD treatment. It is noteworthy that considering the pathophysiological changes occurred in the gastrointestinal tract of IBD patients, especially changes in pH, surface charge, the concentration of reactive oxygen species, and the expression of some biomolecules at the inflamed colon, can help in the rational design of biomaterials-based drug delivery systems for efficient management of IBD. Here, we discuss about targeting these pathophysiological changes using biomaterials-based drug delivery systems, which can provide important clues to establish a strategic roadmap for future studies.

The Therapeutic Role of Short-Chain Fatty Acids Mediated Very Low-Calorie Ketogenic Diet-Gut Microbiota Relationships in Paediatric Inflammatory Bowel Diseases

The very low-calorie ketogenic diet (VLCKD) has been recognized as a promising dietary regimen for the treatment of several diseases. Short-chain fatty acids (SCFAs) produced by anaerobic bacterial fermentation of indigestible dietary fibre in the gut have potential value for their underlying epigenetic role in the treatment of obesity and asthma-related inflammation through mediating the relationships between VLCKD and the infant gut microbiota. However, it is still unclear how VLCKD might influence gut microbiota composition in children, and how SCFAs could play a role in the treatment of inflammatory bowel disease (IBD). To overcome this knowledge gap, this review aims to investigate the role of SCFAs as key epigenetic metabolites that mediate VLCKD-gut microbiota relationships in children, and their therapeutic potential in IBD.

Quantitative Fecal Microbiota Profiles Relate to Therapy Response During Induction With Tumor Necrosis Factor α Antagonist Infliximab in Pediatric Inflammatory Bowel Disease

BACKGROUND

The role of intestinal microbiota in inflammatory bowel diseases is intensively researched. Pediatric studies on the relation between microbiota and treatment response are sparse. We aimed to determine whether absolute abundances of gut microbes characterize the response to infliximab induction in pediatric inflammatory bowel disease.

METHODS

We recruited pediatric patients with inflammatory bowel disease introduced to infliximab at Children's Hospital, University of Helsinki. Stool samples were collected at 0, 2, and 6 weeks for microbiota and calprotectin analyses. We defined treatment response as fecal calprotectin value <100 µg/g at week 6. Intestinal microbiota were analyzed by 16S ribosomal RNA gene amplicon sequencing using the Illumina MiSeq platform. We analyzed total bacterial counts using quantitative polymerase chain reaction and transformed the relative abundances into absolute abundances based on the total counts.

RESULTS

At baseline, the intestinal microbiota in the treatment responsive group (n = 10) showed a higher absolute abundance of Bifidobacteriales and a lower absolute abundance of Actinomycetales than nonresponders (n = 19). The level of inflammation according to fecal calprotectin showed no statistically significant association with the absolute abundances of fecal microbiota. The results on relative abundances differed from the absolute abundances. At the genus level, the responders had an increased relative abundance of Anaerosporobacter but a reduced relative abundance of Parasutterella at baseline.

CONCLUSIONS

High absolute abundance of Bifidobacteriales in the gut microbiota of pediatric patients reflects anti-inflammatory characteristics associated with rapid response to therapy. This warrants further studies on whether modification of pretreatment microbiota might improve the outcomes.

Location-specific signatures of Crohn's disease at a multi-omics scale

BACKGROUND

Crohn's disease (CD), an inflammatory bowel disease (IBD) subtype, results from pathologic interactions between host cells and its resident gut microbes. CD manifests in both isolated disease locations (ileum or colon) or a combination of locations (ileocolonic). To date, a comprehensive understanding of how isolated CD subtypes influence molecular profiles remains outstanding. To address this, we sought to define CD location signatures by leveraging a large cross-sectional feature set captured from the stool of over 200 IBD patients and healthy controls using metaproteomics, shotgun metagenomics, 16S rRNA sequencing, metabolomic profiling, and host genetics paired with clinical endoscopic assessments.

RESULTS

Neither metagenomic nor host genetics alone distinguished CD location subtypes. In contrast, ileal and colonic CD were distinguished using mass spectrometry-based methods (metabolomics or metaproteomics) or a combined multi-omic feature set. This multi-omic feature set revealed colonic CD was strongly associated with neutrophil-related proteins. Additionally, colonic CD displayed a disease-severity-related association with Bacteroides vulgatus. Colonic CD and ulcerative colitis profiles harbored strikingly similar feature enrichments compared to ileal CD, including neutrophil-related protein enrichments. Compared to colonic CD, ileal CD profiles displayed increased primary and secondary bile acid levels and concomitant shifts in taxa with noted sensitivities such as Faecalibacterium prausnitzii or affinities for bile acid-rich environments, including Gammaproteobacteria and Blautia sp. Having shown robust molecular and microbial distinctions tied to CD locations, we leveraged these profiles to generate location-specific disease severity biomarkers that surpass the performance of Calprotectin.

CONCLUSIONS

When compared using multi-omics features, colonic- and ileal-isolated CD subtypes display striking differences that suggest separate location-specific pathologies. Colonic CD's strong similarity to ulcerative colitis, including neutrophil and Bacteroides vulgatus involvement, is also evidence of a shared pathology for colonic-isolated IBD subtypes, while ileal CD maintains a unique, bile acid-driven profile. More broadly, this study demonstrates the power of multi-omics approaches for IBD biomarker discovery and elucidating the underlying biology. Video Abstract.

Anti-Inflammatory Diet Prevents Subclinical Colonic Inflammation and Alters Metabolomic Profile of Ulcerative Colitis Patients in Clinical Remission

A relationship between ulcerative colitis (UC) and diet has been shown in epidemiological and experimental studies. In a 6-month, open-label, randomized, placebo-controlled trial, adult UC patients in clinical remission were randomized to either an “Anti-inflammatory Diet (AID)” or “Canada’s Food Guide (CFG)”. Menu plans in the AID were designed to increase the dietary intake of dietary fiber, probiotics, antioxidants, and omega-3 fatty acids and to decrease the intake of red meat, processed meat, and added sugar. Stool was collected for fecal calprotectin (FCP) and microbial analysis. Metabolomic analysis was performed on urine, serum, and stool samples at the baseline and study endpoint. In this study, 53 patients were randomized. Five (19.2%) patients in the AID and 8 (29.6%) patients in the CFG experienced a clinical relapse. The subclinical response to the intervention (defined as FCP < 150 µg/g at the endpoint) was significantly higher in the AID group (69.2 vs. 37.0%, p = 0.02). The patients in the AID group had an increased intake of zinc, phosphorus, selenium, yogurt, and seafood versus the control group. Adherence to the AID was associated with significant changes in the metabolome, with decreased fecal acetone and xanthine levels along with increased fecal taurine and urinary carnosine and p-hydroxybenzoic acid levels. The AID subjects also had increases in fecal Bifidobacteriaceae, Lachnospiraceae, and Ruminococcaceae. In this study, we found thatdietary modifications involving the increased intake of anti-inflammatory foods combined with a decreased intake of pro-inflammatory foods were associated with metabolic and microbial changes in UC patients in clinical remission and were effective in preventing subclinical inflammation.

The gut fungal and bacterial microbiota in pediatric patients with inflammatory bowel disease introduced to treatment with anti-tumor necrosis factor-α

Pediatric inflammatory bowel disease (PIBD) is a globally increasing chronic inflammatory disease associated with an imbalanced intestinal microbiota and treated with several treatment options, including anti-tumor necrosis factor alpha (TNF-α), such as infliximab (IFX). Up to half of the patients do not respond to the drug and there are no methods for response prediction. Our aim was to predict IFX response from the gut microbiota composition since this is largely unexplored in PIBD. The gut microbiota of 30 PIBD patients receiving IFX was studied by MiSeq sequencing targeting 16S and ITS region from fecal samples collected before IFX and two and six weeks after the start of treatment. The response to IFX induction was determined by fecal calprotectin value < 100 µg/g at week six. The bacterial microbiota differed significantly between response groups, with higher relative abundance of butyrate-producing bacteria in responders compared to non-responders at baseline, validated by high predictive power (area under curve = 0.892) for baseline Ruminococcus and calprotectin. Additionally, non-responders had higher abundance of Candida, while responders had higher abundance of Saccharomyces at the end of the study. The gut microbiota composition in PIBD patients could predict response to IFX treatment in the future.

Fecal Microbiota Transplantation Ameliorates Active Ulcerative Colitis by Downregulating Pro-inflammatory Cytokines in Mucosa and Serum

Background

Ulcerative colitis (UC) is a multi-factor disease characterized by alternating remission periods and repeated occurrence. It has been shown that fecal microbiota transplantation (FMT) is an emerging and effective approach for UC treatment. Since most existing studies chose adults as donors for fecal microbiota, we conducted this study to determine the long-term efficacy and safety of the microbiota from young UC patient donors and illustrate its specific physiological effects.

Methods

Thirty active UC patients were enrolled and FMT were administered with the first colonoscopy and two subsequent enema/transendoscopic enteral tubing (TET) practical regimens in The First Affiliated Hospital of Anhui Medical University in China. Disease activity and inflammatory biomarkers were assessed 6 weeks/over 1 year after treatment. The occurrence of adverse events was also recorded. The samples from blood and mucosa were collected to detect the changes of inflammatory biomarkers and cytokines. The composition of gut and oral microbiota were also sampled and sequenced to confirm the alteration of microbial composition.

Results

Twenty-seven patients completed the treatment, among which 16 (59.3%) achieved efficacious clinical response and 11 (40.7%) clinical remission. Full Mayo score and calprotectin dropped significantly and remained stable over 1 year. FMT also significantly reduced the levels of C-reactive protein (CRP), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6). The gut microbiota altered significantly with increased bacterial diversity and decreased metabolic diversity in responsive patients. The pro-inflammatory enterobacteria decreased after FMT and the abundance of Collinsella increased. Accordingly, the altered metabolic functions, including antigen synthesis, amino acids metabolism, short chain fatty acid production, and vitamin K synthesis of microbiota, were also corrected by FMT.

Conclusion

Fecal microbiota transplantation seems to be safe and effective for active UC patients who are nonresponsive to mesalazine or prednisone in the long-term. FMT could efficiently downregulate pro-inflammatory cytokines to ameliorate the inflammation.

Gut Microbiota: The Potential Key Target of TCM's Therapeutic Effect of Treating Different Diseases Using the Same Method-UC and T2DM as Examples

Traditional Chinese herbal medicine often exerts the therapeutic effect of "treating different diseases with the same method" in clinical practice; in other words, it is a kind of herbal medicine that can often treat two or even multiple diseases; however, the biological mechanism underlying its multi-path and multi-target pharmacological effects remains unclear. Growing evidence has demonstrated that gut microbiota dysbiosis plays a vital role in the occurrence and development of several diseases, and that the root cause of herbal medicine plays a therapeutic role in different diseases, a phenomenon potentially related to the improvement of the gut microbiota. We used local intestinal diseases, such as ulcerative colitis, and systemic diseases, such as type 2 diabetes, as examples; comprehensively searched databases, such as PubMed, Web of Science, and China National Knowledge Infrastructure; and summarized the related studies. The results indicate that multiple individual Chinese herbal medicines, such as Rhizoma coptidis (Huang Lian), Curcuma longa L (Jiang Huang), and Radix Scutellariae (Huang Qin), and Chinese medicinal compounds, such as Gegen Qinlian Decoction, Banxia Xiexin Decoction, and Shenling Baizhu Powder, potentially treat these two diseases by enriching the diversity of the gut microbiota, increasing beneficial bacteria and butyrate-producing bacteria, reducing pathogenic bacteria, improving the intestinal mucosal barrier, and inhibiting intestinal and systemic inflammation. In conclusion, this study found that a variety of traditional Chinese herbal medicines can simultaneously treat ulcerative colitis and type 2 diabetes, and the gut microbiota may be a significant target for herbal medicine as it exerts its therapeutic effect of "treating different diseases with the same method".

Dysbiosis in Inflammatory Bowel Disease: Pathogenic Role and Potential Therapeutic Targets

Microbe-host communication is essential to maintain vital functions of a healthy host, and its disruption has been associated with several diseases, including Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD). Although individual members of the intestinal microbiota have been associated with experimental IBD, identifying microorganisms that affect disease susceptibility and phenotypes in humans remains a considerable challenge. Currently, the lack of a definition between what is healthy and what is a dysbiotic gut microbiome limits research. Nevertheless, although clear proof-of-concept of causality is still lacking, there is an increasingly evident need to understand the microbial basis of IBD at the microbial strain, genomic, epigenomic, and functional levels and in specific clinical contexts. Recent information on the role of diet and novel environmental risk factors affecting the gut microbiome has direct implications for the immune response that impacts the development of IBD. The complexity of IBD pathogenesis, involving multiple distinct elements, suggests the need for an integrative approach, likely utilizing computational modeling of molecular datasets to identify more specific therapeutic targets.

The effect of a hydrolyzed protein diet on the fecal microbiota in cats with chronic enteropathy

The effect of a hydrolyzed protein diet on the fecal microbiota has not been studied in feline chronic enteropathy (CE). Our study aimed to (1) compare the fecal microbiota of cats with CE to control cats with no gastrointestinal signs and (2) determine the effect of a hydrolyzed protein diet on the fecal microbiota of cats with CE and whether this differs between dietary responders and non-responders. The fecal microbiome of cats with CE (n = 36) showed decreased α-diversity in terms of genus richness (P = 0.04) and increased β-diversity in terms of Bray-Curtis Dissimilarity (P < 0.001) compared to control cats (n = 14). Clostridium was the only genera significantly over-represented in cats with CE compared to control cats (adjusted P < 0.1). After 6-weeks of feeding the diet, fifteen cats were classified as responders and 18 as non-responders, based on clinical signs. At the genus level, α-diversity was increased in non-responders versus responders at diagnosis, but decreased after dietary intervention in both groups (P < 0.05). At the family level, non-responders became increasingly dissimilar after dietary intervention (P = 0.012). In general, the abundance of bacteria decreased with feeding a hydrolyzed diet, with the genera most significantly affected being more frequently observed in non-responders. Bifidobacterium was the only genus that increased significantly in abundance post-diet and this effect was observed in both responders and non-responders. Both Oscillibacter and Desulfovibrionaceae_unclassified were most abundant in non-responders at diagnosis but were rarely observed post diet in neither responders nor non-responders. Cats with CE had similar microbiota changes to those described in human inflammatory bowel disease. Whether the presence of Oscillibacter and Desulfovibrionaceae_unclassified are indicators of non-response to the diet at diagnosis requires further investigation. Despite the hydrolyzed diet reducing α-diversity in all cats with CE, this did not resolve gastrointestinal signs in some cats. However, responders metabolized the diet in a similar manner, reflected by sustained β-diversity, while the microbiome of non-responders became increasingly dissimilar compared to diagnosis at the family level. Therefore, the microbiome may not be as tightly regulated in cats with CE that are non-responders and therefore, these cats would require additional therapy for remission of clinical signs.

Prebiotic effects of goji berry in protection against inflammatory bowel disease

The prevalence of inflammatory bowel disease (IBD) is increasing, which is concerning because IBD is a known risk factor for the development of colorectal cancer. Emerging evidence highlights environmental factors, particularly dietary factors and gut microbiota dysbiosis, as pivotal inducers of IBD onset. Goji berry, an ancient tonic food and a nutraceutical supplement, contains a range of phytochemicals such as polysaccharides, carotenoids, and polyphenols. Among these phytochemicals, L. barbarum polysaccharides (LBPs) are the most important functional constituents, which have protective effects against oxidative stress, inflammation, and neurodegeneration. Recently, the beneficial effects of goji berry and associated LBPs consumption were linked to prebiotic effects, which can prevent dysbiosis associated with IBD. This review assessed pertinent literature on the protective effects of goji berry against IBD focusing on the gut microbiota and their metabolites in mediating the observed beneficial effects.

Therapeutic Advances in Gut Microbiome Modulation in Patients with Inflammatory Bowel Disease from Pediatrics to Adulthood

There is mounting evidence that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease (IBD). For the past decade, high throughput sequencing-based gut microbiome research has identified characteristic shifts in the composition of the intestinal microbiota in patients with IBD, suggesting that IBD results from alterations in the interactions between intestinal microbes and the host’s mucosal immune system. These studies have been the impetus for the development of new therapeutic approaches targeting the gut microbiome, such as nutritional therapies, probiotics, fecal microbiota transplant and beneficial metabolic derivatives. Innovative technologies can further our understanding of the role the microbiome plays as well as help to evaluate how the different approaches in microbiome modulation impact clinical responses in adult and pediatric patients. In this review, we highlight important microbiome studies in patients with IBD and their response to different microbiome modulation therapies, and describe the differences in therapeutic response between pediatric and adult patient cohorts.

Use of Faecal Transplantation with a Novel Diet for Mild to Moderate Active Ulcerative Colitis: The CRAFT UC Randomised Controlled Trial

BACKGROUND

We evaluated whether integration of novel diets for donors and patients, in addition to faecal transplantation [FT], could increase FT remission rate in refractory ulcerative colitis [UC].

METHODS

This was a blinded, randomised, controlled trial in adults with active UC, defined by a simple clinical colitis activity index [SCCAI] of ≥5 and ≤11 and endoscopic Mayo score 2-3, refractory to medication. Group 1 received free diet and single donor standard FT by colonoscopy on Day 1and rectal enemas on Days 2 and 14 without dietary conditioning of the donor. Group 2 received FT as above but with dietary pre-conditioning of the donor for 14 days and a UC Exclusion Diet [UCED] for the patients. Group 3 received the UCED alone. The primary endpoint was Week 8 clinical steroid-free remission, defined as SCCAI <3.

RESULTS

Of 96 planned patients, 62 were enrolled. Remission Week 8 Group 1 was 2/17 [11.8%], Group 2 was 4/19 [21.1%], Group 3 was 6/15 [40%] [non-significant]. Endoscopic remission Group 1 was 2/17 [12%], Group 2 was 3/19 [16%], Group 3 was 4/15 [27%] [Group 1 vs 3 p = 0.38]. Mucosal healing [Mayo 0] was achieved only in Group 3 [3/15, 20%] vs 0/36 FT patients [p = 0.022]. Exacerbation of disease occurred in 3/17 [17.6%] of Group 1, 4/19 [21.1%] of Group 2, and 1/15 [6.7%] of Group 3 [Group 2 vs 3, p = 0.35].

CONCLUSIONS

UCED alone appeared to achieve higher clinical remission and mucosal healing than single donor FT with or without diet. The study was stopped for futility by a safety monitoring board.