Gut virome-wide association analysis identifies cross-population viral signatures for inflammatory bowel disease

Microbiome Markers in Gastrointestinal Disorders: Inflammatory Bowel Disease, Colorectal Cancer, and Celiac Disease

Intestinal microbiota and the host's immune system form a symbiotic alliance that sustains normal development and function in the human gut. Changes such as dietary habits among societies in developed countries have led to the development of unbalanced microbial populations in the gut, likely contributing to the dramatic increase in inflammatory diseases in the last few decades. Recent advances in DNA sequencing technologies have tremendously helped to characterize the microbiome associated with disease, both in identifying global alterations and discovering specific biomarkers that potentially contribute to disease pathogenesis, as evidenced by animal studies. Beyond bacterial alterations, non-bacterial components such as fungi, viruses, and microbial metabolites have been implicated in these diseases, influencing immune responses and gut homeostasis. Multi-omics approaches integrating metagenomics, metabolomics, and transcriptomics offer a more comprehensive understanding of the microbiome's role in disease pathogenesis, paving the way for innovative diagnostic and therapeutic strategies. Unraveling the metagenomic profiles associated with disease may facilitate earlier diagnosis and intervention, as well as the development of more personalized and effective therapeutic strategies. This review synthesizes recent and relevant microbiome research studies aimed at characterizing the microbial signatures associated with inflammatory bowel disease, colorectal cancer, and celiac disease.

Characterization of the phyllosphere virome of fresh vegetables and potential transfer to the human gut

Fresh vegetables harbor diverse microorganisms on leaf surfaces, yet their viral communities remain unexplored. We investigate the diversity and ecology of phyllosphere viromes of six leafy green vegetables using virus-like particle (VLP) enrichment and shotgun metagenome sequencing. On average, 9.2 × 107 viruses are present per gram of leaf tissue. The majority (93.1 ± 6.2%) of these viruses are taxonomically unclassified. Virome compositions are distinct among vegetable types and exhibit temporal variations. Virulent phages with replication-enhancing auxiliary metabolic genes (AMGs) are more dominant than temperate phages with host fitness-benefiting AMGs. Analysis of 1498 human fecal VLP metagenomes reveals that approximately 10% of vegetable viruses are present in the human gut virome, including viruses commonly observed in multiple studies. These gut-associated vegetable viruses are enriched with short-term vegetable intake, and depleted in individuals with metabolic and immunologic disorders. Overall, this study elucidates the ecological contribution of the fresh vegetable virome to human gut virome diversity.

The Chinese gut virus catalogue reveals gut virome diversity and disease-related viral signatures

BACKGROUND

The gut viral community has been increasingly recognized for its role in human physiology and health; however, our understanding of its genetic makeup, functional potential, and disease associations remains incomplete.

METHODS

In this study, we collected 11,286 bulk or viral metagenomes from fecal samples across large-scale Chinese populations to establish a Chinese Gut Virus Catalogue (cnGVC) using a de novo virus identification approach. We then examined the diversity and compositional patterns of the gut virome in relation to common diseases by analyzing 6311 bulk metagenomes representing 28 disease or unhealthy states.

RESULTS

The cnGVC contains 93,462 nonredundant viral genomes, with over 70% of these being novel viruses not included in existing gut viral databases. This resource enabled us to characterize the functional diversity and specificity of the gut virome. Using cnGVC, we profiled the gut virome in large-scale populations, assessed sex- and age-related variations, and identified 4238 universal viral signatures of diseases. A random forest classifier based on these signatures achieved high accuracy in distinguishing diseased individuals from controls (AUC = 0.698) and high-risk patients from controls (AUC = 0.761), and its predictive ability was also validated in external cohorts.

CONCLUSIONS

Our resources and findings significantly expand the current understanding of the human gut virome and provide a comprehensive view of the associations between gut viruses and common diseases. This will pave the way for novel strategies in the treatment and prevention of these diseases.

Novel Insights into the Pathogenesis of Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBDs), encompassing Crohn's disease and ulcerative colitis, are complex chronic disorders characterized by an intricate interplay between genetic predisposition, immune dysregulation, gut microbiota alterations, and environmental exposures. This review aims to synthesize recent advances in IBD pathogenesis, exploring key mechanisms and potential avenues for prevention and personalized therapy. A comprehensive literature search was conducted across major bibliographic databases, selecting the most recent and impactful studies on IBD pathogenesis. The review integrates findings from multi-omics analyses, single-cell transcriptomics, and longitudinal cohort studies, focusing on immune regulation, gut microbiota dynamics, and environmental factors influencing disease onset and progression. Immune dysregulation, including macrophage polarization (M1 vs. M2) and Th17 activation, emerges as a cornerstone of IBD pathogenesis. Dysbiosis, as a result of reduced alpha and beta diversity and overgrowth of harmful taxa, is one of the main contributing factors in causing inflammation in IBD. Environmental factors, including air and water pollutants, maternal smoking, and antibiotic exposure during pregnancy and infancy, significantly modulate IBD risk through epigenetic and microbiota-mediated mechanisms. While recent advances have supported the development of new therapeutic strategies, deeply understanding the complex dynamics of IBD pathogenesis remains challenging. Future efforts should aim to reduce the burden of disease with precise, personalized treatments and lower the incidence of IBD through early-life prevention and targeted interventions addressing modifiable risk factors.

Does preeclampsia impact the gut microbiota of preterm offspring during early infancy?

Preeclampsia (PE) is a pregnancy complication characterized by high blood pressure and organ damage. This study investigates the differences in the gut microbiota between preterm neonates born to mothers with PE and those born to mothers without PE (PR), aiming to understand how maternal health conditions like PE influence neonatal gut microbiota. The early gut microbiota plays a crucial role in neonatal health, and disturbances in its development can have long-term consequences. Fecal samples were collected from preterm neonates of PE and PR mothers at 2 and 6 weeks postpartum and analyzed using shotgun metagenomic sequencing. We found that PE significantly affected the gut microbial composition of preterm neonates, particularly at 2 weeks postpartum. The gut microbial diversity in the PE_2 group was notably lower compared to the PR_2 group, with no significant difference observed between the PR_6 and PE_6 groups. At the phylum level, Firmicutes and Proteobacteria were predominant, with significant differences observed, particularly a lower abundance of Actinobacteria in the PE_2 group. At the genus level, Escherichia, Enterococcus, and Klebsiella were more prevalent in the PE_2 group, whereas Bifidobacterium and Cutibacterium dominated the PR_2 group. The gut virome analysis showed no significant differences among the groups. Functional analysis revealed distinct metabolic pathway activities across the groups, suggesting that early disturbances due to PE impact the establishment of healthy gut microbiota. These findings underscore the substantial influence of maternal health on the early development of the neonatal gut microbiota and highlight the potential long-term health consequences. Additionally, the differences in metabolic pathways further emphasize the impact of preeclampsia on gut microbiota functionality.

A metagenome-wide study of the gut virome in chronic kidney disease

Rationale: Chronic kidney disease (CKD) is a progressively debilitating condition leading to kidney dysfunction and severe complications. While dysbiosis of the gut bacteriome has been linked to CKD, the alteration in the gut viral community and its role in CKD remain poorly understood. Methods: Here, we characterize the gut virome in CKD using metagenome-wide analyses of faecal samples from 425 patients and 290 healthy individuals. Results: CKD is associated with a remarkable shift in the gut viral profile that occurs regardless of host properties, disease stage, and underlying diseases. We identify 4,649 differentially abundant viral operational taxonomic units (vOTUs) and reveal that some CKD-enriched viruses are closely related to gut bacterial taxa such as Bacteroides, [Ruminococcus], Erysipelatoclostridium, and Enterocloster spp. In contrast, CKD-depleted viruses include more crAss-like viruses and often target Faecalibacterium, Ruminococcus, and Prevotella species. Functional annotation of the vOTUs reveals numerous viral functional signatures associated with CKD, notably a marked reduction in nicotinamide adenine dinucleotide (NAD+) synthesis capacity within the CKD-associated virome. Furthermore, most CKD viral signatures are reproducible in the gut viromes of diabetic kidney disease and several other common diseases, highlighting the considerable universality of disease-associated viromes. Conclusions: This research provides comprehensive resources and novel insights into the CKD-associated gut virome, offering valuable guidance for future mechanistic and therapeutic investigations.

Combination of Youhua Kuijie Prescription and sulfasalazine can alleviate experimental colitis via IL-6/JAK2/STAT3 pathway

Introduction

Youhua Kuijie prescription (YHKJ) is a hospital preparation that is composed of nine kinds of herbs. Sulfasalazine (SASP) is widely used as a first-line clinical treatment for UC. Traditional Chinese medicine and Western medicine have their own advantages in the treatment of UC, and the mechanism of YHKJ combined with SASP in the treatment of UC needs to be investigated.

Methods

In this study, the therapeutic mechanism of YHKJ combined with SASP in the treatment of UC was predicted by network pharmacology and molecular docking. The chemical components and related targets of YHKJ were obtained from the TCMSP database. The chemical structure of SASP was obtained from the PubChem server, and related targets of SASP molecules were identified using the PharmMapper database. UC-related targets were obtained from the DisGeNET, GeneCards, OMIM, TTD, DrugBank and PharmGkb databases.

Results

In total, 197 shared targets were identified by constructing a Venn diagram. PPI network data obtained from the STRING database were imported into Cytoscape to visualize the "drug-disease" target network, and STAT3 was selected as the core target by topological analysis. Gene Ontology revealed the biological functions of target genes, and KEGG analysis revealed that the core target STAT3 was differentially expressed in Th17 cells and the JAK-STAT signaling pathway. Thus, the core target STAT3 was subjected to molecular docking with the top 10 components, including nine YHKJ components (quercetin, luteolin, ursolic acid, daidzein, kaempferol, wogonin, myricetin, formononetin, indirubin) and SASP (C18H14N4O5S). The molecular docking results showed that STAT3 had favorable binding with the nine YHKJ components and SASP; STAT3 had the strongest binding with ursolic acid (-10.26 kcal/mol), followed by SASP (-8.54 kcal/mol). Qualitative analysis of the chemical constituents of YHKJ by HPLC revealed that sitosterol, ursolic acid, myricetin, daidzein, quercetin, kaempferol and formononetin were the main components. Additional experiments verified that YHKJ combined with SASP inhibited activation of the IL-6/JAK2/STAT3 pathway and alleviated inflammation in UC model rats.

Discussion

Our results showed that seven chemical components in YHKJ cooperate with SASP to interfere with activation of the IL-6/JAK2/STAT3 pathway, thus playing a role in the treatment of UC.