Enterococcus faecium

What was studied?

This pilot study applied an integrative multi-omics workflow to identify plasma metabolite, lipid, and gut-microbiome signatures associated with sarcopenia. Sarcopenia is the age-related decline in muscle mass and strength, and the researchers combined plasma metabolomics, lipidomics, and 16S rRNA gut-microbiome sequencing to look for markers linked to the condition. Participants were classified as sarcopenic or non-sarcopenic using EWGSOP2 criteria, which incorporate grip strength, chair rise time, psoas muscle cross-sectional area on CT, and the SARC-F screening score.

Who was studied?

The cohort consisted of forty community-dwelling older adults, aged 60 to 87 years, from an Indian population. Of these, fifteen were classified as sarcopenic and twenty-five as non-sarcopenic based on EWGSOP2 criteria. This was a pilot study, so the sample size was small and intended to generate preliminary integrative findings rather than definitive population-level estimates.

What were the most important findings?

Dominant hand grip strength was the strongest clinical predictor of sarcopenia, with an AUROC of 0.93. Sarcopenic subjects showed higher systemic inflammation, reflected in an elevated neutrophil-to-lymphocyte ratio, and elevated plasma arachidonic acid compared to non-sarcopenic subjects. Thirteen lipid species, primarily lysophosphatidylcholines, lysophosphatidylethanolamines, and hexosylceramides, were identified as discriminating between the two groups, and a support vector machine model with recursive feature elimination was used to identify these discriminative metabolites, with gut microbiome profiles correlated against the metabolite patterns. The abstract as provided does not mention Faecalibacterium prausnitzii, butyrate, or anti-inflammatory commensals specifically.

What are the greatest implications of this study?

The findings suggest that sarcopenia in older adults is accompanied by a distinct signature of systemic inflammation, altered lipid metabolism, and arachidonic acid elevation that can be captured through integrative multi-omics profiling. Combining clinical measures like grip strength with plasma metabolomic, lipidomic, and gut-microbiome data may help identify biological markers of sarcopenia beyond physical function tests alone. Because this was a small pilot study within an Indian cohort, larger and more diverse studies would be needed before these metabolite, lipid, and microbiome signatures could be used as validated diagnostic or monitoring tools.

What was studied?

This study examined whether alterations in the gut microbiome track the development of Parkinson's disease (PD) in people who carry GBA1 gene variants but have not (yet) developed PD symptoms. The researchers combined clinical data with fecal metagenomics and used an analysis method that assessed both differential abundance of microbial species and the coherence of that abundance variation across groups, measured with Cliff's delta. The goal was to determine whether microbiome composition could serve as an early marker of PD risk in genetically at-risk individuals.

Who was studied?

The primary cohort included 271 patients with PD, 43 carriers of GBA1 variants who had not developed PD symptoms (GBA-NMC), and 150 healthy controls. Findings were then checked against three independent cohorts from the United States, Korea, and Turkey, together comprising 638 additional PD patients and 319 additional healthy controls. In total, the study drew on clinical and fecal metagenomic data from close to 1,400 individuals across four countries.

What were the most important findings?

About 25% of the gut microbiome in GBA-NMC individuals showed a composition that was intermediate between healthy controls and patients with PD. This intermediate microbiome signature was strongly correlated with disease progression in patients who already had PD, and with prodromal symptoms suggestive of future PD in both GBA-NMC and healthy individuals. Similar microbiome alterations were reproduced across the three independent international cohorts, strengthening confidence that the pattern is not specific to one population.

What are the greatest implications of this study?

The findings suggest gut microbiome changes can flag both genetically at-risk (GBA1 carriers) and non-genetically at-risk people in the general population who may be on a trajectory toward developing PD. This positions the microbiome as a potential early, non-invasive marker during the premanifest phase of disease, before clinical symptoms appear. Such a marker could eventually help identify candidates for early monitoring or intervention trials aimed at delaying or preventing PD onset.

What was studied?

Extranodal natural killer/T-cell lymphoma (ENKTL) predominantly manifests in East Asia and Latin America. Despite shared intrinsic factors, such as ethnic and genetic backgrounds, the progression of ENKTL can be influenced by extrinsic factors related to changing lifestyle patterns.

Who was studied?

This study collected stool samples from newly diagnosed (ND)-ENKTL patients (n=40) and conducted whole genome shotgun sequencing.

What were the most important findings?

ND-ENKTL revealed reduced alpha diversity in ND-ENKTL compared to healthy controls (HCs) (p=0.008), with Enterobacteriaceae abundance significantly contributing to the beta diversity difference between ENKTL and HCs (p < 0.001). Functional analysis indicated upregulated aerobic metabolism and degradation of aromatic compounds in ND-ENKTL. Enterobacteriaceae were associated not only with clinical data explaining disease status (serum C-reactive protein, stage, prognosis index of natural killer cell lymphoma [PINK], and PINK-E) but also with clinical outcomes (early relapse and short progression-free survival). The relative abundance of Enterobacteriaceae at the family level was similar between ENKTL and diffuse large B-cell lymphoma (DLBCL) (p=0.140). However, the ENKTL exhibited a higher abundance of Escherichia, in contrast to the prevalence of Enterobacter and Citrobacter in DLBCL. Linear regression analysis demonstrated a significant association between Escherichia abundance and programmed cell death-ligand-1 (PD-L1) levels in tissue samples (p=0.025), whereas no correlation with PD-L1 was observed for Enterobacteriaceae at the family level (p=0.571).

What are the greatest implications of this study?

ND-ENKTL exhibited an abundance of Enterobacteriaceae and a dominant presence of Escherichia. These microbial characteristics correlated with disease status, treatment outcomes, and PD-L1 expression, suggesting the potential of the ENKTL microbiome as a biomarker and cause of lymphomagenesis, which warrants further exploration.

What was studied?

This study profiled the fecal virome, bacteriome, and blood metabolome together in schizophrenia, testing whether gut viruses (mainly bacteriophages) shape the disease-associated bacterial community and whether those shifts reach the host through circulating metabolites.

Who was studied?

Forty-nine first-episode schizophrenia patients, most drug-naive or treated for fewer than five days, and 49 age-, sex-, and BMI-matched healthy controls at West China Hospital, Sichuan University (2021 to 2022). Fecal shotgun sequencing covered 95 participants and untargeted plasma metabolomics 92, with age, sex, BMI, and medication days controlled.

What were the most important findings?

Bacterial beta-diversity separated patients from controls at the family, genus, and species levels while alpha-diversity did not differ, and combining MaAsLin2 with ANCOM-BC flagged 7, 14, and 45 differentially abundant taxa respectively. The healthy viral-bacterial transkingdom correlation network was largely lost in schizophrenia, and the co-occurring metabolites were enriched in bile-acid and eicosanoid pathways linked to inflammation. A serial-mediation model supported a gut viruses to bacteria to metabolites to schizophrenia chain, with metabolites carrying most of the indirect effect.

What are the greatest implications of this study?

The results frame schizophrenia-associated dysbiosis as a virome-bacteriome-metabolome system rather than a bacterial shift alone, and highlight bile-acid and eicosanoid (COX and prostaglandin) metabolism as microbiota-linked, potentially treatable inflammatory routes. As a small cross-sectional study, it establishes associations and candidate biomarkers, not causation.

What was studied?

The colonization and evolution of gut microbiota early in life play a vital role in shaping a healthy, robust immune system for infant health, whether in combating short-term illness or improving long-term health outcomes. Early-life clinical practices may interrupt or disrupt the normal colonization process of the infant gut microbiota, thereby increasing disease susceptibility. In this prospective cohort study, we analyzed the gut microbiota of 46 term and 23 preterm infants using 16S rRNA gene metagenomic sequencing. Fecal samples were collected at six timepoints during the first three months of life. Notably, gestational age was the main factor contributing to differences in the meconium microbial composition. Intriguingly, our study unveiled a more homogeneous microbial composition in preterm infants with more abundant Bifidobacterium from the postnatal age (PNA) of one month. Concurrently, the beneficial bacteria Bifidobacterium and Lactobacillus gradually increased, and the potentially pathogenic bacteria Clostridium, Enterobacter, Enterococcus, Klebsiella, and Pseudomonas gradually decreased. Furthermore, our study underscored a link between decreased microbial diversity of preterm infants and exclusive breastfeeding and antibiotic exposure. Moreover, preterm infants with patent ductus arteriosus (PDA) exhibited reduced microbial diversity but higher abundances of Streptococcus oralis and Streptococcus mitis.

What was studied?

This study examined whether rifaximin, a gut-specific non-absorbable antibiotic, could reduce gut-derived systemic inflammation in severe acute pancreatitis (SAP). The researchers combined murine experimental models with a single-center, open-label randomized controlled trial (ChiCTR2100049794). They assessed pancreatic injury, systemic inflammatory markers, and gut microbiota composition, and tested whether rifaximin's effects depended on modulating the microbiota by using antibiotic-treated and germ-free mice.

Who was studied?

The animal component used murine models of severe acute pancreatitis, including antibiotic-treated and germ-free mice used to probe the mechanism. The clinical component enrolled 60 patients with predicted severe acute pancreatitis, randomized to receive rifaximin or standard control treatment. No further demographic details are given in the abstract.

What were the most important findings?

In mice, rifaximin reduced pancreatic injury and systemic inflammation and decreased mucin-degrading gut genera such as Akkermansia, but its protective effects persisted even in antibiotic-treated and germ-free mice, indicating mechanisms beyond microbiota modulation. In patients, rifaximin significantly lowered systemic inflammation, with white blood cell count falling from a median of 11.50 x10^9/L to 8.49 x10^9/L and TNF-alpha falling from 15.05 pg/mL to 11.00 pg/mL. However, the rate of culture-confirmed infection was identical between rifaximin and control groups (13.3% vs 13.3%), and adverse events were comparable between groups.

What are the greatest implications of this study?

The findings suggest rifaximin can dampen systemic inflammation in severe acute pancreatitis through mechanisms that are not solely dependent on reshaping the gut microbiota, pointing to a possible direct anti-inflammatory or barrier-protective effect. Because inflammation markers improved without any change in infection risk, rifaximin may offer a safe adjunct for controlling inflammatory injury in SAP without added infectious risk. This supports further investigation of rifaximin as a therapeutic strategy for gut-derived inflammation in acute pancreatitis, alongside continued study of its non-microbiota-dependent mechanisms.

What was studied?

Ancient DNA (aDNA) analysis of archaeological dental calculus has provided a wealth of insights into ancient health, demography and lifestyles. However, the workflow for ancient metagenomics is still evolving, raising concerns about reproducibility. Few systematic investigations have examined how DNA extraction methods and library preparation protocols influence ancient oral microbiome recovery, despite evidence from modern populations suggesting that they do. This leaves a gap in our understanding of how wet-lab protocols impact aDNA recovery from dental calculus. In this study, we apply two DNA extraction and two library preparation methods in the aDNA field on dental calculus samples from Hungary and Niger. Samples from each context have similar chronological ages, but differences in their levels of aDNA preservation are notable, providing additional insights into how the efficacy of wet-lab protocols is impacted by sample preservation. Several metrics were employed to assess intra- and inter-sample variability, such as DNA fragment length recovery, GC content, clonality, endogenous content, DNA deamination and microbial composition. Our findings indicate that both DNA extraction and library preparation protocols can considerably impact ancient DNA recovery from archaeological dental calculus. Furthermore, no single protocol consistently outperformed the others across all assessments, and the effectiveness of specific protocol combinations depended on the preservation of the sample. These findings highlight the challenges of meta-analyses and underscore the need to account for technical variability. Lastly, our study raises the question of whether the field should strive to standardise methods for comparability or optimise protocols based on sample preservation and specific research objectives.

What was studied?

This study investigated how type 2 diabetes mellitus (T2DM) affects the vaginal microbiota in perimenopausal and postmenopausal women. Researchers used metagenomic sequencing of vaginal secretion samples to characterize microbial community structure and functional homeostasis. They assessed alpha diversity (Observe, ACE, Shannon-Weaver, Gini-Simpson indices) and beta diversity (PCoA, NMDS), and applied taxonomic profiling, LEfSe analysis, co-occurrence network construction, and neutral community modeling to determine whether stochastic or deterministic processes shaped the community.

Who was studied?

The study included 22 women with T2DM (the DM group) and 23 healthy women (the CT group), all in perimenopausal or postmenopausal life stages. The two groups did not differ significantly in age (62.22 plus or minus 5.74 years vs. 58.23 plus or minus 7.55 years, p = 0.052) or in the proportion of perimenopausal versus postmenopausal participants (3/19 vs. 5/18, p = 0.748). This design allowed the researchers to isolate the effect of T2DM on the vaginal microbiota independent of age or menopausal status.

What were the most important findings?

The DM group showed significantly higher alpha diversity than the control group (p < 0.05), along with distinct clustering on beta diversity analysis (p < 0.05). This shift was marked by reduced Lactobacillus abundance in the diabetic women compared to healthy controls. The abstract indicates additional taxonomic and network-level differences were identified through LEfSe and co-occurrence analyses, alongside evidence bearing on stochastic versus deterministic community assembly, though the abstract text provided does not detail every specific taxon or network finding beyond the Lactobacillus reduction.

What are the greatest implications of this study?

The findings suggest that T2DM is associated with a less Lactobacillus-dominated, more diverse and heterogeneous vaginal microbial community in perimenopausal and postmenopausal women, independent of age or menopausal stage. Since a Lactobacillus-depleted vaginal environment is generally linked to reduced protective function, this points to T2DM as a distinct driver of vaginal dysbiosis risk in this population. These results underscore the need to consider metabolic status, not just menopause, when evaluating vaginal microbiome health and potential dysbiosis-adjustment strategies in aging women.

What was studied?

This study examined the tracheal and cecal microbiome composition across three broiler chicken genotypes including a heritage New Hampshire × Columbian cross (NHC) and modern Ross × Ross 308 (R308) and Ross YP × Ross 708 (R708) broilers, using full-length 16S rRNA sequencing. Birds were reared in floor pens, and at 56 d of age, cecal and tracheal samples were collected from 8 birds per genotype and subjected to DNA extraction followed by PCR amplification of full-length 16S rRNA. Obtained amplified PCR product was sequenced using MinION. A total of 1.8 million reads for tracheal samples and 1.2 million reads for ceca samples were obtained from 24 birds. Despite similar alpha diversity matrixes (Shannon, Simpson, Pielou's evenness, and Chao1) across genotypes in both tracheal and cecal samples, beta diversity analysis revealed significant differences in community composition. Tracheal and cecal microbiota varied significantly among genotypes, particularly NHC with the R308 and R708 groups. At the phylum level, Bacillota (Firmicutes) dominated both tracheal and cecal samples across genotypes. In the trachea, NHC and R708 birds exhibited high relative abundance of Enterococcus cecorum, while Jeotgalicoccus meleagridis dominated R308. Differential abundance analysis showed higher abundance of potentially beneficial bacteria such as Limosilactobacillus pontis and Aerococcus viridans in R308 and R708, while NHC birds had higher levels of species like Merdibacter massiliensis and Agathobaculum butyriciproducens. Cecal microbiome analysis revealed genotype-specific enrichment of species, with NHC birds showing higher abundance of potential pathogens like Shigella boydii and Escherichia fergusonii compared to R708. In contrast, R308 birds harboured more potentially beneficial taxa, including Lactobacillus acidophilus and Limosilactobacillus vaginalis, compared to R708. Pairwise comparisons further highlighted Intestinibacter bartlettii and other potentially beneficial microbes being significantly enriched in R308 over R708. Overall, while microbial richness remained consistent, significant genotype-associated differences in bacterial community structure and genotype-specific microbial abundance were observed, emphasizing the influence of host genetics on microbiota composition and potential implications for poultry health and performance.

What was studied?

This study aimed to investigate the differences in gut microbiota composition and diversity among healthy controls (HC) and patients with colorectal lesions-including common colorectal polyps, small colorectal adenomas (SCRA), large colorectal adenomas (LCRA), and intramucosal carcinoma (IMC)-to identify bacterial species associated with disease progression and provide novel insights into the diagnosis and treatment of CRC based on the "polyp-adenoma-carcinoma" sequence.

Who was studied?

A total of 250 participants were recruited from the First Affiliated Hospital of Anhui Medical University between July 2023 and June 2024. The cohort included 30 HC, 52 with common colorectal polyps, 58 with SCRA, 56 with LCRA, and 54 with IMC. Fecal samples were collected for bacterial DNA extraction, followed by metagenomic sequencing to analyze microbial diversity. Differential microbiota analysis was performed using the R package microbiomeMarker and LEfSe. Group classification and feature identification were conducted using a random forest model. Functional profiling was performed using DIAMOND against the KEGG and MetaCyc databases.

What were the most important findings?

No significant differences in α-diversity were observed across the groups. β-diversity analysis revealed significant differences in Bray-Curtis and Jaccard distances among the groups. The composition and abundance of gut microbiota at the phylum, class, order, family, genus, and species levels were significantly altered. LEfSe analysis identified specific bacterial species with significant differences in IMC compared to other groups. Furthermore, the random forest model effectively distinguished patients with IMC from other groups based on distinct microbial signatures. Functional profiling revealed that the gut microbiota undergoes metabolic reprogramming from a homeostatic to a pro-tumorigenic phenotype during CRC progression as well as reduced protective pathway abundance and impaired energy/biosynthetic metabolism in CRC-associated microbiota.

What are the greatest implications of this study?

Gut microbiota profiles varied significantly among HC, polyp, SCRA, LCRA, and IMC groups. Specific microbial signatures were able to effectively differentiate IMC from both HC and non-malignant colorectal lesions, highlighting their potential as diagnostic biomarkers.

What was studied?

This study examined the longitudinal development of infant gut microbiota and its relationship to tetanus toxoid vaccine responses. Researchers used 16S rRNA gene sequencing to profile gut microbiota at two early-life time points, under one week and 15 weeks of age. They evaluated whether HIV exposure without infection altered microbiota composition and succession, and whether these microbiota patterns were linked to anti-tetanus antibody titers measured by enzyme-linked immunosorbent assay.

Who was studied?

The study included 278 infants total, drawn from two cohorts: 82 South African infants (61 exposed to HIV but uninfected, and 21 HIV-unexposed and uninfected) and 196 Nigerian infants (141 exposed to HIV but uninfected, and 55 HIV-unexposed and uninfected). All infants were assessed at both the under-one-week and 15-week time points. Feeding practice was also documented, noting that the Nigerian infants were exclusively breastfed.

What were the most important findings?

Gut microbiota composition and its succession over the first 15 weeks of life were shaped more strongly by geographic location and infant age than by HIV exposure status. Nigerian infants underwent a dramatic microbiota shift over this period, becoming dominated by Bifidobacterium longum subspecies infantis, a shift not seen in South African infants even when the analysis was restricted to exclusively breastfed babies. Using Least Absolute Shrinkage and Selection Operator (LASSO) regression, the study found that HIV exposure and gut microbiota composition were each independently associated with tetanus antibody titers at 15 weeks, with high passively transferred maternal antibody also playing a role.

What are the greatest implications of this study?

The findings suggest that geography and associated feeding and environmental practices are more powerful drivers of early infant gut microbiota development than HIV-exposure status alone. The emergence of Bifidobacterium longum subspecies infantis dominance in exclusively breastfed Nigerian infants, but not South African infants, points to population-specific factors shaping microbiota maturation beyond breastfeeding alone. Because gut microbiota and HIV exposure independently predicted vaccine antibody responses, these results support further investigation into microbiota-targeted strategies to optimize infant immune and vaccine responses across diverse populations.

What was studied?

This study used shotgun metagenome sequencing to track the taxonomic and functional evolution of the faecal microbiota in piglets during the first two weeks after weaning. It compared three management strategies: in-feed antibiotics, therapeutic zinc oxide, and no medication, in the context of post weaning diarrhoea (PWD), a major driver of antimicrobial use. The goal was to understand how removing these interventions, as required by new EU regulations, affects the piglet gut microbiota and to inform alternative approaches to controlling PWD.

Who was studied?

The subjects were post weaning piglets housed on commercial farms that routinely use antimicrobials during the post weaning period. Animals were divided into three experimental groups receiving in-feed antibiotics, therapeutic zinc oxide, or no medication. Faecal samples were collected and analyzed across multiple days post weaning and across multiple farms, though the abstract does not give an exact animal count.

What were the most important findings?

Microbiota diversity was affected by day post weaning, treatment, and diarrhoea status, but not by which farm the pigs were on, and composition shifted toward dominance by groups such as Prevotella spp. by day 14. Zinc oxide inhibited E. coli overgrowth, increased abundance of the family Bacteroidaceae, and decreased Megasphaera spp. Pigs treated with antibiotics showed inconsistent taxonomic changes over time, with an overall rise in Limosilactobacillus reuteri and Megasphaera elsdenii. Non-medicated pigs showed virulence-related functions at day 7 post weaning.

What are the greatest implications of this study?

The findings show that zinc oxide has a more consistent, taxonomically defined suppressive effect on E. coli overgrowth than in-feed antibiotics, which produced more variable microbiota changes over time. This distinction is relevant as the EU restricts both interventions and producers seek alternatives to control post weaning diarrhoea. The detection of virulence-related functions in non-medicated pigs early after weaning underscores the vulnerability of the unmedicated microbiota during this period and the need for new, function-informed strategies to manage it.

What was studied?

Gastric cancer is one of the global health concerns. A series of studies on the stomach have confirmed the role of the microbiome in shaping gastrointestinal diseases. Delineation of microbiome signatures to distinguish chronic gastritis from gastric cancer will provide a non-invasive preventative and treatment strategy. In this study, we performed whole metagenome shotgun sequencing of fecal samples to enhance the detection of rare bacterial species and increase genome sequence coverage. Additionally, we employed multiple bioinformatics approaches to investigate the potential targets of the microbiome as an indicator of differentiating gastric cancer from chronic gastritis.

What were the most important findings?

A total of 65 patients were enrolled, comprising 33 individuals with chronic gastritis and 32 with gastric cancer. Within each group, the chronic gastritis group was sub-grouped into intestinal metaplasia (n = 15) and non-intestinal metaplasia (n = 18); the gastric cancer group, early stage (stages 1 and 2, n = 13) and late stage (stages 3 and 4, n = 19) cancer. No significant differences in alpha and beta diversities were detected among the patient groups. However, in a two-group univariate comparison, higher Fusobacteria abundance was identified in phylum; Fusobacteria presented higher abundance in gastric cancer (LDA scored 4.27, q = 0.041 in LEfSe). Age and sex-adjusted MaAsLin and Random Forest variable of importance (VIMP) analysis in species provided meaningful features; Bacteria_caccae was the most contributing species toward gastric cancer and late-stage cancer (beta:2.43, se:0.891, p:0.008, VIMP score:2.543). In contrast, Bifidobacterium_longum significantly contributed to chronic gastritis (beta:-1.8, se:0.699, p:0.009, VIMP score:1.988). Age, sex, and BMI-adjusted MasAsLin on metabolic pathway analysis showed that GLCMANNANAUT-PWY degradation was higher in gastric cancer and one of the contributing species was Fusobacterium_varium.

What are the greatest implications of this study?

Microbiomes belonging to the pathogenic phylum Fusobacteria and species Bacteroides_caccae and Streptococcus_anginosus can be significant targets for monitoring the progression of gastric cancer. Whereas Bifidobacterium_longum and Lachnospiraceae_bacterium_5_1_63FAA might be protection biomarkers against gastric cancer.

What was studied?

This study characterized the tongue coating microbiome in relation to colorectal cancer (CRC) using metagenomic shotgun sequencing. The researchers compared microbial species diversity and functional pathways across tongue coating samples from cancer patients, precancerous polyp patients, and healthy individuals. They also examined whether distinguishable tongue fur types could be defined by the microbial communities present. A random forest model was built and tested to see whether tongue coating microbiome data could predict CRC status.

Who was studied?

The study included 90 participants divided into three equal groups of 30: patients with colorectal cancer, patients with colorectal polyps, and healthy controls. Tongue coating samples were collected directly from each participant for metagenomic sequencing. No further demographic details are given in the abstract.

What were the most important findings?

CRC samples showed greater species diversity than the other groups, along with a more prominent nucleoside and nucleotide biosynthesis pathway. Distinct species combinations across participants formed three separable tongue fur types. Using tongue coating microbiome profiling, a random forest model achieved an AUC of 0.915 in distinguishing CRC patients from controls, with Atopobium rimae, Streptococcus sanguinis, and Prevotella oris identified as key differentiating species.

What are the greatest implications of this study?

This is described as the first study to link tongue coating microbiome composition to colorectal cancer, suggesting the tongue could serve as a convenient, non-invasive sampling site for CRC-related biomarkers. The high discriminatory accuracy (AUC 0.915) points to potential diagnostic or screening applications based on tongue coating microbiota. The identification of distinct fur types also offers a new framework for understanding oral microbial community structure in relation to systemic disease. No mention of Candida, fungi, or the mycobiome appears in this abstract.

What was studied?

This study examined how environmental, socioeconomic, and health factors relate to gut microbiome composition at both the species and strain level. Researchers used deeply sequenced metagenomic data to identify associations between bacterial species and a range of host phenotypes and situational factors. They also performed a meta-analysis of species-level profiles across multiple datasets to look for consistent patterns, such as links to body mass index.

Who was studied?

The study drew on a community-based cohort of 1,871 people living in 19 isolated villages in the Mesoamerican highlands of western Honduras. This is a non-industrialized, geographically isolated population, a setting the authors note remains uncommon in deep gut microbiome sequencing studies. Additional comparisons were made using species-level profiles from other, unspecified datasets as part of a meta-analysis.

What were the most important findings?

Socioeconomic factors accounted for 51.44% of all associations found between the gut microbiome and human phenotypes, making them the dominant category of influence. Meta-analysis across datasets identified several bacterial species associated with body mass index, consistent with prior research. Incorporating strain-level phylogenetic information changed the overall picture of host-microbiome relationships, especially for factors like household wealth, where wealthier individuals were found to harbor different strains of Eubacterium rectale than less wealthy individuals.

What are the greatest implications of this study?

The findings suggest that socioeconomic circumstances are a major driver of gut microbiome variation, potentially more so than many other individual health factors. The demonstration that strain-level differences (not just species presence) track with wealth indicates that species-level analysis alone can miss biologically meaningful variation. The authors conclude that gut microbiome surveillance in such populations could help illuminate broader patterns relevant to both individual and public health.

What was studied?

This study used whole-genome shotgun sequencing and gas chromatography/mass spectrometry to profile gut microbial and metabolic signatures across seven different malignancies. The researchers compared taxonomic and metabolomic configurations in cancer patients against sex- and age-matched healthy controls. The goal was to identify both common and cancer-type-specific gut microbiome and metabolite alterations.

Who was studied?

The study included patients with colorectal cancer (40), stomach cancer (45), breast cancer (71), lung cancer (34), melanoma (50), lymphoid neoplasms (60), and acute myeloid leukemia (40). Each cancer group was compared against its own sex- and age-matched healthy control group. In total the analysis spanned 300 cancer patients across seven malignancy types plus their matched controls.

What were the most important findings?

Beta-diversity differed between every cancer group and its healthy controls, while alpha-diversity differed only for the lymphoid neoplasm and acute myeloid leukemia groups. Of 203 unique species identified, 179 were under-represented and 24 were over-represented in cancer patients relative to controls. Faecalibacillus intestinalis was under-represented across all seven cancer groups, and Anaerostipes hadrus was under-represented in all groups except stomach cancer, with a marked reduction in the gut microbiome cancer index in every group except acute myeloid leukemia. Among the short-chain fatty acids and amino acids tested, formic acid concentration was significantly altered.

What are the greatest implications of this study?

The consistent depletion of Faecalibacillus intestinalis and altered formic acid levels across seven distinct cancer types suggest these may represent shared, cross-cancer markers of gut dysbiosis rather than disease-specific findings. This points toward a common gut microbial and metabolic signature that could inform future pan-cancer diagnostic or monitoring approaches. Because the pattern held despite differences in cancer biology and location, it strengthens the case for a generalizable link between gut dysbiosis and malignancy.

What was studied?

This study examined how exclusive enteral nutrition (EEN), a first-line therapy for pediatric Crohn's disease, produces its protective effects on the gut. The researchers used integrated multi-omics analysis of fecal microbiota and metabolites to identify functional network clusters associated with treatment response. They further validated these diet-driven microbiome changes using gut chemostat cultures and by transferring microbiota into germ-free Il10-deficient mice.

Who was studied?

The abstract describes a prospective pediatric cohort of treatment-naive Crohn's disease patients, registered as German Clinical Trials DRKS00013306, who were followed as they began EEN therapy. Exact patient numbers are not given in the abstract. Findings from this human cohort were then extended experimentally using gnotobiotic (germ-free) Il10-deficient mice colonized with patient-derived microbiota.

What were the most important findings?

Multi-omics analysis identified individually variable microbiome network clusters, with Lachnospiraceae and medium-chain fatty acids emerging as protective features associated with EEN response. Bioorthogonal non-canonical amino acid tagging pinpointed specific bacterial species that responded to medium-chain fatty acids, and metagenomic analysis revealed high strain-level dynamics during EEN therapy. When patient-derived microbiota were transferred into gnotobiotic Il10-deficient mice, individual patient-specific strain signatures could either prevent or cause inflammatory bowel disease-like inflammation.

What are the greatest implications of this study?

The findings show that EEN operates through explicit, functional, and highly individualized changes in the fecal microbiome rather than a single uniform mechanism. Because protective effects were tied to specific strains and metabolites such as medium-chain fatty acids, this suggests that microbiome and metabolite profiling could help predict or enhance EEN response in pediatric Crohn's disease. The demonstration that individual strain signatures can causally prevent or induce inflammation in a gnotobiotic model also supports strain-level and metabolite-targeted approaches as a path toward more precise dietary or microbial therapies for Crohn's disease.

What was studied?

Constipation is a common symptom in maintenance hemodialysis patients and greatly affects the quality of survival of hemodialysis patients. Fecal microbiota transplantation and probiotics are feasible treatments for functional constipation, but there is still a gap in the research on the characteristics of gut flora in patients with maintenance hemodialysis combined with constipation. The aim of this study is to clarify the characteristics of the intestinal flora and its changes in maintenance hemodialysis patients with constipation.

Who was studied?

Fecal samples were collected from 45 participants, containing 15 in the maintenance hemodialysis constipation group,15 in the maintenance hemodialysis non-constipation group and 15 in the healthy control group. These samples were analyzed using 16S rRNA gene sequencing. The feature of the intestinal microbiome of maintenance hemodialysis constipation group and the microbiome differences among the three groups were elucidated by species annotation analysis, α-diversity analysis, β-diversity analysis, species difference analysis, and predictive functional analysis.

What were the most important findings?

The alpha diversity analysis indicated that maintenance hemodialysis constipation group was less diverse and homogeneous than maintenance hemodialysis non-constipation group and healthy control group. At the genus level, the top ten dominant genera in maintenance hemodialysis constipation group patients were Enterococcus, Escherichia-Shigella, Bacteroides, Streptococcus, Bifidobacterium, Ruminococcus_gnavus_group, Lachnospiraceae_unclassified, Faecalibacterium, Akkermansia and UCG-002. Compared with non-constipation group, the Enterococcus, Rhizobiales_unclassified, Filomicrobium, Eggerthella, Allobaculum, Prevotella_7, Gordonibacter, Mitochondria_unclassified, Lachnoanaerobaculum were significantly higher in constipation group (p<0.05). Compared with non-constipation group, the Kineothrix, Rhodopirellula, Weissella were significantly lower in constipation group (p<0.05). The predictive functional analysis revealed that compared with non-constipation group, constipation group was significantly enriched in pathways associated with pyruate metabolism, flavonoid biosynthesis.

What are the greatest implications of this study?

This study describes for the first time the intestinal microbiome characteristics of maintenance hemodialysis patients with constipation. The results of this study suggest that there is a difference in the intestinal flora between maintenance hemodialysis patients with constipation and maintenance hemodialysis patients without constipation.

What was studied?

This study used metagenomic sequencing to examine how chemotherapy affects the gut microbiota and antibiotic resistance genes (ARGs) in patients with acute leukemia (AL). Researchers compared stool samples collected before and after chemotherapy to track shifts in microbial composition and resistance gene carriage. The analysis also explored how antibiotic dosage shapes microbiota and ARG networks, and how gut microbial species relate to circulating inflammatory markers.

Who was studied?

The subjects were patients diagnosed with acute leukemia who provided stool samples both before and after undergoing chemotherapy. The abstract does not give an exact number of patients, so the precise cohort size cannot be stated. Blood samples from these same patients were also analyzed for inflammatory biomarkers alongside the paired stool metagenomes.

What were the most important findings?

Post-chemotherapy stool samples showed decreased alpha diversity and greater sample-to-sample dispersion compared with pre-chemotherapy samples, along with shifts in the abundance of specific bacterial taxa. Enterococcus, Klebsiella, and Escherichia coli were identified as the most prevalent carriers of antibiotic resistance genes. Correlation analysis linked specific microbial species to inflammatory markers, including C-reactive protein (CRP) and adenosine deaminase (ADA), and co-occurrence networks connected 179 microbial and ARG nodes across 206 edges. Treatment with cephamycin and sulfonamide antibiotics was associated with the emergence of multidrug-resistant Klebsiella colonization.

What are the greatest implications of this study?

The findings suggest that chemotherapy in acute leukemia patients disrupts gut microbial balance in ways that favor colonization by resistant, potentially pathogenic Enterobacteriaceae members such as Klebsiella and E. coli. The observed links between specific antibiotics, resistant bacteria, and inflammatory biomarkers highlight the need for careful antibiotic selection and dosing during leukemia treatment to limit multidrug-resistant colonization. These data support closer monitoring of gut microbiota and ARG dynamics as a tool for anticipating infection risk and inflammatory complications in immunocompromised leukemia patients.

What was studied?

This study investigated the neonatal gut bacterial and viral microbiome in infants exposed to HIV but who remained uninfected, and examined how this exposure relates to inflammatory biomarkers in plasma. The researchers also tested whether HIV exposure alters antibody-microbiota binding in the neonatal gut. Finally, they assessed whether antibodies present in breast milk affect the growth of commensal gut bacteria.

Who was studied?

The study compared neonates exposed to HIV but uninfected (nHEU) with unexposed, uninfected neonates (nHU). Breast milk from mothers living with HIV was also analyzed and compared for its antibody function. The abstract does not give specific sample sizes, so the exact cohort size cannot be stated.

What were the most important findings?

Neonates exposed to HIV but uninfected showed an altered gut bacteriome and a milder change in the enteric DNA virome compared to unexposed neonates. HIV exposure also differentially affected IgA binding to gut microbiota. The relative abundance of Blautia spp., in both whole stool and IgA-bound microbiota, was positively associated with plasma C-reactive protein levels. Breast milk IgA from mothers living with HIV showed a significantly reduced ability to inhibit the growth of Blautia coccoides, and this reduced inhibitory capacity was associated with inflammation in the exposed neonates.

What are the greatest implications of this study?

The findings suggest that elevated inflammation in HIV-exposed but uninfected neonates may stem in part from a weakened capacity of maternal breast milk IgA to control specific commensal bacteria such as Blautia coccoides. This points to a potential antibody-mediated mechanism linking maternal HIV status, infant gut microbiota composition, and systemic inflammation in the infant. Understanding this pathway could inform strategies to support healthy immune development in this vulnerable population.

What was studied?

The gut microbiome influences cancer development and the efficacy and safety of chemotherapy but little is known about its effects on lymphoma. We obtained stool samples from treatment-naive, newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL) (n = 189). We first performed 16S ribosomal RNA gene sequencing (n = 158) and then conducted whole-genome shotgun sequencing on additional samples (n = 106). We compared the microbiome data from these patients with data from healthy controls and assessed whether microbiome characteristics were associated with treatment outcomes. The alpha diversity was significantly lower in patients with DLBCL than in healthy controls (P < .001), and the microbial composition differed significantly between the groups (P < .001). The abundance of the Enterobacteriaceae family belonging to the Proteobacteria phylum was markedly higher in patients than in healthy controls. Functional analysis of the microbiome revealed an association with opportunistic pathogenesis through type 1 pili, biofilm formation, and antibiotics resistance. Enterobacteriaceae members were significantly enriched in patients who experienced febrile neutropenia and in those who experienced relapse or progression (P < .001). Interestingly, greater abundance of Enterobacteriaceae correlated with shorter progression-free survival (P = .007). The cytokine profiles of patients whose microbiome was enriched with Enterobacteriaceae were significantly associated with interleukin 6 (P = .035) and interferon gamma (P = .045) levels. In summary, patients with DLBCL exhibited gut microbial dysbiosis. The abundance of Enterobacteriaceae correlated with treatment outcomes and febrile neutropenia. Further study is required to elucidate the origin and role of gut dysbiosis in DLBCL.

What was studied?

This study examined whether alterations in the gut microbiome are linked not just to COVID-19 severity but to COVID-19 prognosis. Researchers performed genome-resolved metagenomic analysis on fecal samples to identify microbial genomes associated with disease severity. They then grouped these genomes into co-abundance "guilds" and tested whether a guild-based index could predict clinical outcomes.

Who was studied?

The study analyzed fecal samples from 300 in-hospital COVID-19 patients, collected at the time of hospital admission. Patients were classified into mild, moderate, and severe or critical severity groups. The guild-level microbiome index was further validated across patients in different countries and compared against COVID-19 patients, pneumonia controls, and healthy subjects in four independent data sets.

What were the most important findings?

Redundancy analysis identified 33 high quality metagenome-assembled genomes that differed across severity groups, and these organized into two competing guilds. Guild 1 carried more genes for short-chain fatty acid biosynthesis and fewer genes for virulence and antibiotic resistance compared with Guild 2. The resulting guild-level microbiome index (GMI) classified patients by severity group with an average AUROC of 0.83, correlated with 8 clinical parameters predictive of prognosis on day 7, and was associated with death or discharge outcome in critical patients.

What are the greatest implications of this study?

The findings show that the gut microbiome's relationship to COVID-19 is genome-specific rather than simply taxon-specific, since two competing functional guilds, one linked to short-chain fatty acid production and one linked to virulence and resistance genes, tracked with disease severity. Because GMI at admission was consistently associated with clinical trajectory and distinguished COVID-19 patients from pneumonia controls and healthy subjects across independent data sets, this genome-resolved guild-level signature may help identify hospitalized patients at high risk of severe outcomes early, at the time of admission.

What was studied?

This study examined whether the gut microbiome could be used to differentiate and diagnose Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel disease (IBD). Researchers compared the abundance and composition of gut microbiota across disease states and looked for specific biomarkers linked to disease activity. The work also examined how microbial diversity changed as disease progressed through different stages.

Who was studied?

The abstract describes patients with IBD, split into CD and UC groups, compared against healthy controls (HC). Specific numbers of participants, demographics, and enrollment details are not given in the abstract, so the exact cohort size and characteristics cannot be stated. The comparison design (IBD patients versus healthy controls, with CD and UC analyzed separately) is the only population detail confirmed.

What were the most important findings?

Gut microbiome diversity was lower in IBD patients than in healthy controls, and this reduction was significantly more pronounced in CD patients. The researchers identified 68 microbiota members associated with these diseases, 28 linked to CD and 40 linked to UC. Microbial diversity also declined further as disease progressed through more advanced stages. Specific taxa tracked with severity: Alistipes shahii and Pseudodesulfovibrio aespoeensis abundances were negatively correlated with CD severity, while Polynucleobacter wianus abundance was positively associated with it.

What are the greatest implications of this study?

These findings suggest the gut microbiome could serve as a diagnostic tool to distinguish CD from UC, addressing a clinically difficult differential diagnosis. Identifying species whose abundance correlates with disease severity points toward potential microbial biomarkers for monitoring disease activity and staging. Such biomarkers could support more precise, long-term treatment planning for IBD patients.

What was studied?

This study examined whether gut microbiota composition influences the return of estrus in post-weaning sows by regulating the metabolism of sex steroid hormones. The researchers used 16S rRNA gene sequencing, metagenomic sequencing, and fecal metabolome analysis to link microbial community changes to hormone-related outcomes. They specifically looked at how shifts in gut bacterial species affect the functional capacity for steroid hormone biosynthesis within the gut microbiome.

Who was studied?

The study analyzed 207 fecal samples from well-phenotyped sows using 16S rRNA gene sequencing to find associations between gut microbes and estrus return. A subset of 85 fecal samples underwent metagenomic sequencing to identify specific bacterial species tied to estrus return status. The findings were then confirmed in a separate validation cohort of sows.

What were the most important findings?

Metagenomic analysis identified 37 bacterial species significantly associated with estrus return after weaning. Sows that returned to normal estrus had increased abundances of L. reuteri and P. copri, and decreased abundances of B. fragilis, S. suis, and B. pseudolongum, compared to non-returning sows. These microbial shifts significantly altered the gut microbiome's functional capacity for steroid hormone biosynthesis, and metabolome analysis found significant differences in sex steroid hormones and related compounds between normal and non-return sows.

What are the greatest implications of this study?

By integrating differential bacterial species, metagenomic function, and fecal metabolome data, the study provides evidence that gut microbiota, including reduced B. fragilis abundance, is linked to normal post-weaning estrus return through effects on sex steroid hormone metabolism. This suggests that specific gut bacteria could serve as biomarkers or targets for improving reproductive efficiency in sows. The findings point toward potential microbiome-based strategies to address delayed or absent estrus return, a costly problem in swine production.

What was studied?

This study used metagenomic shotgun sequencing to characterize the oral microbiota, antibiotic resistance genes (ARGs), and virulence genes (VirGs) associated with periodontitis. The researchers examined shifts in microbial community composition and functional pathways in periodontitis compared with controls. They also analyzed selection pressure on ARGs and VirGs using the Ka/Ks ratio to determine whether these genes were being positively selected in the oral microbiome.

Who was studied?

The abstract describes periodontitis patients compared with control subjects, though it does not specify exact sample sizes or demographic details. The researchers combined their own metagenomic sequencing data with a previously published periodontitis dataset for the gene selection analysis. No cohort age range, geographic origin, or recruitment setting is given in the abstract.

What were the most important findings?

Periodontitis patients showed a significant shift in oral microbiota composition along with several functional pathways that were more abundant than in controls. Several ARGs and VirGs showed evidence of positive selection (Ka/Ks ratio greater than 1) across both datasets analyzed. Notably, 5 of 12 positively selected ARGs and VirGs found in periodontitis patients were also present in the genomes of respiratory tract pathogens, and most background VirGs carried non-synonymous mutations consistent with natural selection.

What are the greatest implications of this study?

The overlap between positively selected virulence and resistance genes in periodontal bacteria and respiratory pathogens suggests a possible mechanistic link between periodontitis and respiratory infection. This raises the possibility that oral microbial communities could act as a reservoir for genes that enhance virulence or antibiotic resistance in distant infection sites. The findings support closer surveillance of oral microbiota as a factor in respiratory disease risk and antibiotic resistance spread, though further studies are needed to establish causality.

What was studied?

Psoriasis is a chronic, inflammatory skin disease that affects 2‒3% of the global population. Besides skin manifestations, patients with psoriasis have increased susceptibility to a number of comorbidities, including psoriatic arthritis, cardiovascular disease, and inflammatory bowel disease. To understand the systemic component of psoriasis pathogenesis, we performed a pilot study to examine the fecal metagenome, host colonic transcriptome, and host peripheral blood immune profiles of patients with psoriasis and healthy controls. Our study showed increased functional diversity in the gut microbiome of patients with psoriasis. In addition, we identified microbial species that preferentially associate with patients with psoriasis and which have been previously found to associate with other autoimmune diseases. Intriguingly, our data revealed three psoriasis subgroups that have distinct microbial and host features. Integrating these features revealed host‒microbe associations that are specific to psoriasis or particular psoriasis subgroups. Our findings provide insight into the factors that may affect the development of comorbidities in patients with psoriasis and may hold diagnostic potential for early identification of patients with psoriasis at risk for these comorbidities.

What was studied?

We explored the fecal microbiota in pediatric patients <18 years of age with treatment-naïve IBD (80 Crohn’s disease (CD), 27 ulcerative colitis (UC)), in 50 non-IBD patients with gastrointestinal symptoms without inflammation and in 75 healthy children. Using a targeted qPCR approach, the quantities of more than 100 different bacterial species were measured. Results: The bacterial abundance was statistically significantly reduced in the IBD and non-IBD patients compared to the healthy children for several beneficial species. The CD patients had a lower abundance of Bifidobacterium species compared to the UC patients, and the IBD patients in need of biologic therapy had a lower abundance of butyrate producing bacteria. Based on the abundance of bacterial species at diagnosis, we constructed Diagnostic, Phenotype and Prognostic Indexes. Patients with a high Diagnostic Index had 2.5 times higher odds for having IBD than those with a lower index. The CD patients had a higher Phenotype Index than the UC patients. Patients with a high Prognostic Index had 2.1 higher odds for needing biologic therapy compared to those with a lower index. Conclusions: The fecal abundance of bacterial species can aid in diagnosing IBD, in distinguishing CD from UC and in identifying children with IBD in need of biologic therapy.

What was studied?

The human microbiome has been strongly correlated with disease pathology and outcomes, yet remains relatively underexplored in patients with malignant endometrial disease. In this study, vaginal microbiome samples were prospectively collected at the time of hysterectomy from 61 racially and ethnically diverse patients from three disease conditions: 1) benign gynecologic disease (controls, n=11), 2) low-grade endometrial carcinoma (n=30), and 3) high-grade endometrial carcinoma (n=20). Extracted DNA underwent shotgun metagenomics sequencing, and microbial α and β diversities were calculated. Hierarchical clustering was used to describe community state types (CST), which were then compared by microbial diversity and grade. Differential abundance was calculated, and machine learning utilized to assess the predictive value of bacterial abundance to distinguish grade and histology. Both α- and β-diversity were associated with patient tumor grade. Four vaginal CST were identified that associated with grade of disease. Different histologies also demonstrated variation in CST within tumor grades. Using supervised clustering algorithms, critical microbiome markers at the species level were used to build models that predicted benign vs carcinoma, high-grade carcinoma versus benign, and high-grade versus low-grade carcinoma with high accuracy. These results confirm that the vaginal microbiome segregates not just benign disease from endometrial cancer, but is predictive of histology and grade. Further characterization of these findings in large, prospective studies is needed to elucidate their potential clinical applications.

What was studied?

This study investigated how probiotic supplementation affects the gut microbiota of extremely preterm infants in the neonatal intensive care unit. Probiotics were already known to reduce necrotizing enterocolitis (NEC) risk in this population, but the underlying mechanism was unclear. The researchers used a prospective cohort design to compare gut microbiota composition between infants who received probiotics and those who did not. They also examined whether probiotic exposure was associated with clinical outcomes such as NEC, late-onset sepsis, and duration of total parenteral nutrition.

Who was studied?

The cohort consisted of 120 extremely preterm neonates with a gestational age of 28 weeks or less. Infants were enrolled between August 2019 and December 2021 and divided into a study group that received probiotics and a control group that did not. This was a real-world clinical NICU population rather than a public dataset or animal model.

What were the most important findings?

Neonates who received probiotics had a significantly increased abundance of Lactobacillus compared with the control group (adjusted odds ratio 4.33, 95% CI 1.89 to 9.96, p = 0.009). The probiotic group also spent significantly fewer days on total parenteral nutrition (median 29.0 days versus 35.5 days, p = 0.004). In addition, the probiotic group had a significantly lower rate of late-onset sepsis than the control group.

What are the greatest implications of this study?

The findings suggest that probiotics may benefit extremely preterm infants partly by reshaping the gut microbiota toward greater Lactobacillus abundance, alongside reductions in parenteral nutrition duration and late-onset sepsis. This offers a plausible microbiota-mediated mechanism linking probiotic use to previously reported reductions in NEC and other neonatal morbidities. The results support continued clinical use of probiotics in extremely preterm NICU populations and point to gut microbiota composition as a relevant marker for future studies of probiotic mechanisms in this vulnerable group.

What was studied?

This work re-analyzed three previously published shotgun metagenomic datasets (NCBI SRA accessions PRJNA687519, PRJNA724913, and PRJNA395911) to test how geographic location, respiratory sampling niche, and transportation stress shape the cattle (bovine) respiratory microbiome and its predicted function. The authors examined microbial diversity, composition, co-occurrence networks, and KEGG functional profiles, and assessed which opportunistic pathogens shifted after transportation in relation to bovine respiratory disease (BRD).

Who was studied?

A total of 145 respiratory samples were analyzed from feedlot calves aged 5 to 6 months across three geographic locations: Saskatoon (Canada), the cities of Qiqihaer and Guangan (China), and Alberta (Canada). Samples spanned two niches, comprising 130 nasopharyngeal swabs and 15 bronchoalveolar lavage (lung) samples, the latter collected at necropsy from calves that died of BRD. Sequencing used the Illumina HiSeq platform (shotgun metagenomics), yielding an average of 3,374,490 clean reads per sample, with taxonomy assigned via RefSeq and function via the KEGG Orthology database.

What were the most important findings?

Nasopharyngeal alpha diversity (Shannon index) was higher in the China samples (Qiqihaer and Guangan) than in the Saskatoon nasopharynx or the Alberta lung, and composition clustered distinctly by location (for example, ANOSIM R = 0.99, p = 0.001 between Saskatoon and China). Of high-quality reads, 96.72 percent were bacterial across 27 phyla; the Saskatoon nasopharynx was dominated by Proteobacteria (91.19 percent), whereas the China nasopharynx was more balanced (Proteobacteria 48.49 and 61.94 percent, Firmicutes 24.26 and 17.68 percent, Actinobacteria 14.90 and 9.40 percent, Bacteroidetes 6.59 and 6.98 percent) and the Alberta lung was dominated by Proteobacteria (58.27 percent), Firmicutes (17.03 percent), Tenericutes (14.27 percent), and Bacteroidetes (8.41 percent). Long-distance transportation significantly reduced nasopharyngeal richness at unloading and after adaptive feeding and increased BRD-associated pathogens after feedlot arrival, whereas short-distance transportation did not; the 15 BRD lung samples separated into four clusters dominated by different pathogens.

What are the greatest implications of this study?

The authors conclude that geography, sampling niche, and transportation (especially long-distance shipping) are important factors shaping the bovine respiratory microbiome and BRD, and that distinct pathogen-dominated lung clusters may reflect different subtypes of BRD pathogenesis. Because this is an observational re-analysis of existing metagenomic datasets, the results describe associations rather than causation, and the authors note the small number of lung samples as a limitation.

What was studied?

This study investigated specific alterations in the gut microbiome and serum metabolome in polycystic ovary syndrome (PCOS) and how the two systems interact. Researchers used shotgun metagenomic sequencing on stool samples and ultrahigh performance liquid chromatography quadrupole time-of-flight mass spectrometry on serum to profile microbial and metabolite changes. They then built an integrative network combining the metagenomics and metabolomics datasets to map possible interactions between gut bacteria and circulating metabolites. This network-derived hypothesis was further tested using fecal microbiota transplantation (FMT) in a rat trial.

Who was studied?

The human portion of the study involved stool and serum samples from 32 patients with PCOS and 18 healthy controls. The abstract does not provide further demographic details such as age range or geographic location. The mechanistic findings were additionally tested in a rat model via fecal microbiota transplantation, not in additional human subjects.

What were the most important findings?

Fecal metagenomics identified 64 microbial strains that differed significantly between PCOS patients and healthy controls, with about half of these enriched in the PCOS group. These altered species were associated with disruption of host metabolic homeostasis, including insulin resistance and fatty acid metabolism, and with heightened inflammatory signaling such as the PI3K/Akt/mTOR pathway. The bacteria appeared linked to these effects partly through expression of sterol regulatory element-binding transcription factor-1, serine/threonine-protein kinase mTOR, and 3-oxoacyl-[acyl-carrier-protein] synthase III. The abstract does not mention Faecalibacterium prausnitzii, butyrate, or other anti-inflammatory commensals specifically.

What are the greatest implications of this study?

The findings suggest that specific gut microbial strains may causally contribute to the metabolic and inflammatory disturbances seen in PCOS, rather than merely correlating with the condition. The use of an integrative metagenome-metabolome network, validated through fecal microbiota transplantation in rats, strengthens the case for a functional gut microbiome to host metabolism link. This points to the gut microbiome and its metabolic outputs as potential targets for future diagnostic or therapeutic strategies in PCOS. Further human studies would be needed to confirm causality and clinical relevance.

What was studied?

This study examined the gut microbiome in Parkinson's disease (PD) using large-scale, high-resolution shotgun metagenomic sequencing of fecal DNA. The researchers applied uniform, standardized methods throughout, followed by metagenome-wide association studies requiring agreement between two independent statistical methods (ANCOM-BC and MaAsLin2) before declaring a disease association. They also conducted network analysis to identify clusters of co-occurring microbial species and functional profiling to characterize microbial genes and pathways.

Who was studied?

The study enrolled 490 individuals with Parkinson's disease and 234 control individuals. Fecal samples from this cohort underwent deep shotgun sequencing to generate the metagenomic data analyzed in the study. The abstract does not provide further demographic detail on the participants.

What were the most important findings?

Over 30 percent of the species, genes, and pathways tested showed altered abundances in Parkinson's disease, indicating widespread dysbiosis. PD-associated species organized into polymicrobial clusters that grew, shrank, or competed together rather than acting independently. The PD microbiome was disease permissive: it showed overabundance of pathogens and immunogenic components, dysregulated neuroactive signaling, an excess of molecules that induce alpha-synuclein pathology, and overproduction of toxicants, alongside a reduction in anti-inflammatory and neuroprotective factors that would otherwise support recovery.

What are the greatest implications of this study?

By validating in human PD patients findings previously seen only in experimental models, this study strengthens the case that the gut microbiome contributes to multiple disease mechanisms in Parkinson's disease. The reconciliation of prior human PD microbiome literature helps resolve inconsistencies across earlier studies and establishes a more standardized foundation for future research. The reduction in anti-inflammatory and neuroprotective microbial factors points to a loss of protective capacity that may limit the body's ability to counteract disease processes, suggesting the microbiome as a potential target for future mechanistic and therapeutic investigation.

What was studied?

The application of clinical mNGS for diagnosing respiratory infections improves etiology diagnosis, however at the same time, it brings new challenges as an unbiased sequencing method informing all identified microbiomes in the specimen.

Who was studied?

Strategy evaluation and metagenomic analysis were performed for the mNGS data generated between March 2017 and October 2019. Diagnostic strengths of four specimen types were assessed to pinpoint the more appropriate type for mNGS diagnosis of respiratory infections. Microbiome complexity was revealed between patient cohorts and infection types. A bioinformatic pipeline resembling diagnosis results was built based upon multiple bioinformatic parameters.

What were the most important findings?

The positive predictive values (PPVs) for mNGS diagnosing of non-mycobacterium, Nontuberculous Mycobacteria (NTM), and Aspergillus were obviously higher in bronchoalveolar lavage fluid (BALF) demonstrating the potency of BALF in mNGS diagnosis. Lung tissues and sputum were acceptable for diagnosis of the Mycobacterium tuberculosis (MTB) infections. Interestingly, significant taxonomy differences were identified in sufficient BALF specimens, and unique bacteriome and virome compositions were found in the BALF specimens of tumor patients. Our pipeline showed comparative diagnostic strength with the clinical microbiological diagnosis.

What are the greatest implications of this study?

To achieve reliable mNGS diagnosis result, BALF specimens for suspicious common infections, and lung tissues and sputum for doubtful MTB infections are recommended to avoid the false results given by the complexed respiratory microbiomes. Our developed bioinformatic pipeline successful helps mNGS data interpretation and reduces manual corrections for etiology diagnosis.

What was studied?

This study examined the gut microbial composition and structure associated with colorectal cancer (CRC) across populations from different geographic regions. Researchers used whole-genome sequencing (WGS) data, annotated with MetaPhlAn2, to determine species and genus level relative abundance. They applied PCA and LEfSe analysis to compare microbial differences between regional datasets and used Spearman correlation analysis to examine relationships among CRC-associated differential species. The ultimate goal was to build and verify CRC risk prediction models based on these regional microbial differences.

Who was studied?

The analysis drew on a metagenomic dataset of 601 samples collected from six countries, sourced from the GMrepo and NCBI databases. This represents a secondary analysis of previously generated whole-genome sequencing data rather than a newly recruited clinical cohort. The abstract does not specify individual patient demographics such as age or sex, only the multi-country, multi-sample composition of the dataset.

What were the most important findings?

The composition of the intestinal bacterial community varied by region, and the specific differential intestinal bacteria linked to CRC were inconsistent from country to country. Despite this regional variability, the researchers identified a common diversity of bacteria shared across all six countries, including Peptostreptococcus. These findings indicate that CRC-associated microbiota show both a conserved core signature and considerable geographic variation.

What are the greatest implications of this study?

The findings suggest that CRC risk prediction models based on gut microbiota may need to account for regional differences in microbial composition rather than assuming a universal signature. Identifying bacteria that are consistently associated with CRC across diverse populations, such as Peptostreptococcus, could support more broadly generalizable diagnostic or risk-assessment tools. At the same time, the region-specific differences highlight the importance of validating any microbiome-based CRC model within the population it will be applied to.

What was studied?

This study examined the gut microbiota of patients with COVID-19 pneumonia using 16S rRNA gene sequencing performed on rectal swabs. Researchers compared microbial composition and diversity between patients treated in the intensive care unit (i-COVID19), patients treated in infectious disease wards (w-COVID19), and healthy controls (CTRL). The goal was to characterize how gut microbial communities differ across varying levels of COVID-19 disease severity.

Who was studied?

The study population consisted of patients hospitalized with COVID-19 pneumonia, divided into two groups by care setting: those admitted to the intensive care unit and those managed in infectious disease wards. These two patient groups were compared against a control group without COVID-19. The abstract does not report exact sample sizes, ages, or other demographic details for these cohorts.

What were the most important findings?

Patients in the ICU showed a decrease in the Chao1 index compared to both controls and ward patients, indicating lower microbial richness in the most severely ill patients, while the Shannon index showed no significant change. At the phylum level, ward patients showed an increase in Proteobacteria compared to controls. Fusobacteria and Spirochetes were both decreased relative to controls, with Spirochetes showing the greatest decrease in ICU patients specifically.

What are the greatest implications of this study?

The findings indicate that gut microbial communities shift in composition and richness according to COVID-19 disease severity, with the most pronounced changes occurring in critically ill ICU patients. These preliminary results suggest the gut microbiota may hold promising biomarkers for diagnosing COVID-19 and gauging disease severity. The authors note that validation in larger cohorts could support using microbiota profiles to help stratify patients by severity.

What was studied?

This study examined how SARS-CoV-2 infection affects the gut microbiome, looking at both the bacteriome and the virome together. The researchers investigated whether gut bacterial and viral communities shift during COVID-19 infection and whether these shifts relate to disease severity. They also used a mouse COVID-19 model to test whether SARS-CoV-2 infection alone could reproduce similar gut microbial changes and to examine immune and infection-related gene expression in gut epithelial cells.

Who was studied?

The human portion of the study involved a cohort of 13 COVID-19 patients in Beijing, China, compared with five healthy controls. Patients were further grouped by disease severity (mild to moderate versus severe) to compare gut bacteriome and virome composition. The findings from this human cohort were then replicated in a mouse model of COVID-19.

What were the most important findings?

The gut virome and bacteriome of COVID-19 patients were notably different from those of healthy controls, with a bacterial dysbiosis signature marked by reduced diversity and viral shifts. Among patients, bacterial and viral composition differed by disease severity, though these differences were not entirely separable from the effect of antibiotics. Severe cases showed a greater abundance of opportunistic pathogens and were depleted for butyrate-producing groups of bacteria compared with mild to moderate cases. The mouse model confirmed virome differences and bacteriome dysbiosis from SARS-CoV-2 infection, alongside differential expression of immune and infection-related genes in gut epithelial cells.

What are the greatest implications of this study?

The results suggest that SARS-CoV-2 infection measurably disrupts gut bacteriome and virome composition, not just respiratory tract microbiology. Because compositional signatures differed with severity, including depletion of butyrate-producing bacteria in severe cases, the gut microbiome may reflect or even contribute to disease severity and recovery. This points to the gut bacteriome and virome as a potential avenue for understanding COVID-19 progression and treatment outcomes, though the mixing of antibiotic effects with infection effects in the human cohort means further work is needed to disentangle these contributions.

What was studied?

This study examined changes in intestinal bacterial communities across healthy people, patients with inflammatory bowel disease (IBD), and patients with colorectal cancer (CRC). The researchers performed metagenome-wide association studies on fecal samples to characterize bacterial community structure, relative abundance, and functional predictions. They also analyzed differentially abundant bacteria and co-occurrence networks to compare the three groups.

Who was studied?

The analysis drew on fecal metagenomic data from 290 healthy subjects, 512 IBD patients, and 285 CRC patients. Healthy and CRC data were obtained from the European Nucleotide Archive under several study accession numbers, while IBD patient data came from the Integrated Human Microbiome Project via the Human Microbiome Project Data Portal. This makes the cohort a large, multi-source pooled metagenomic dataset rather than a single newly recruited study population.

What were the most important findings?

The bacterial community structure in both IBD and CRC patients differed significantly from that of healthy subjects. Notably, IBD patients showed low intestinal bacterial diversity, while CRC patients showed high intestinal bacterial diversity, a contrasting pattern between the two disease states. The abstract does not specify Faecalibacterium prausnitzii, butyrate, or other named commensals, so no claim is made about those organisms here.

What are the greatest implications of this study?

The finding that IBD and CRC involve opposite directions of diversity change suggests these two diseases are associated with distinct, rather than uniform, disruptions of the gut microbiome. This distinction could help refine how metagenomic diversity and community structure are used to distinguish disease states from health and from each other. It also underscores the value of large, pooled public metagenomic datasets for characterizing disease-associated microbial signatures.

What was studied?

Evidence is mounting that the gut-brain axis plays an important role in mental diseases fueling mechanistic investigations to provide a basis for future targeted interventions. However, shotgun metagenomic data from treatment-naïve patients are scarce hampering comprehensive analyses of the complex interaction between the gut microbiota and the brain. Here we explore the fecal microbiome based on 90 medication-free schizophrenia patients and 81 controls and identify a microbial species classifier distinguishing patients from controls with an area under the receiver operating characteristic curve (AUC) of 0.896, and replicate the microbiome-based disease classifier in 45 patients and 45 controls (AUC = 0.765). Functional potentials associated with schizophrenia include differences in short-chain fatty acids synthesis, tryptophan metabolism, and synthesis/degradation of neurotransmitters. Transplantation of a schizophrenia-enriched bacterium, Streptococcus vestibularis, appear to induces deficits in social behaviors, and alters neurotransmitter levels in peripheral tissues in recipient mice. Our findings provide new leads for further investigations in cohort studies and animal models.

What was studied?

The relationship between the composition and function of gut microbial communities and early-onset calcium oxalate kidney stone disease is unknown.

Who was studied?

We conducted a case-control study of 88 individuals aged 4-18 years, which included 44 individuals with kidney stones containing ≥50% calcium oxalate and 44 controls matched for age, sex, and race. Shotgun metagenomic sequencing and untargeted metabolomics were performed on stool samples.

What were the most important findings?

Participants who were kidney stone formers had a significantly less diverse gut microbiome compared with controls. Among bacterial taxa with a prevalence >0.1%, 31 taxa were less abundant among individuals with nephrolithiasis. These included seven taxa that produce butyrate and three taxa that degrade oxalate. The lower abundance of these bacteria was reflected in decreased abundance of the gene encoding butyryl-coA dehydrogenase (P=0.02). The relative abundance of these bacteria was correlated with the levels of 18 fecal metabolites, and levels of these metabolites differed in individuals with kidney stones compared with controls. The oxalate-degrading bacterial taxa identified as decreased in those who were kidney stone formers were components of a larger abundance correlation network that included Eggerthella lenta and several Lactobacillus species. The microbial (α) diversity was associated with age of stone onset, first decreasing and then increasing with age. For the individuals who were stone formers, we found the lowest α diversity among individuals who first formed stones at age 9-14 years, whereas controls displayed no age-related differences in diversity.

What are the greatest implications of this study?

Loss of gut bacteria, particularly loss of those that produce butyrate and degrade oxalate, associates with perturbations of the metabolome that may be upstream determinants of early-onset calcium oxalate kidney stone disease.

What was studied?

This study examined changes in the fecal (gut) microbiome of patients hospitalized with COVID-19 over the course of their illness. Researchers used shotgun metagenomic sequencing to profile fecal samples collected repeatedly during hospitalization, from admission until discharge. The aim was to determine whether gut microbiome composition tracked with disease severity and with fecal shedding of SARS-CoV-2. Comparisons were made against patients with community-acquired pneumonia and against healthy individuals.

Who was studied?

The study population was 15 patients with confirmed COVID-19 who were hospitalized in Hong Kong between February 5 and March 17, 2020. Fecal samples were collected two or three times per week from each patient from hospitalization through discharge. Disease severity among these patients was categorized as mild, moderate, severe, or critical based on respiratory and clinical criteria. Two comparison groups were also included: 6 subjects with community-acquired pneumonia and 15 healthy individuals serving as controls.

What were the most important findings?

Patients with COVID-19 showed significant alterations in their gut microbiome composition compared to both the community-acquired pneumonia group and the healthy controls, as stated in the abstract. Gut microbiome profiles were assessed in relation to disease severity and to fecal shedding of SARS-CoV-2, indicating that microbiome features were linked to both the clinical course of infection and viral persistence in stool. The abstract does not provide the specific taxa, effect sizes, or statistical values underlying these associations, so no individual organisms or magnitudes can be reported here.

What are the greatest implications of this study?

The findings suggest that the gut microbiome may be an active participant in, or at least a marker of, COVID-19 severity and gastrointestinal viral shedding rather than a passive bystander. This raises the possibility that gut microbiome status could eventually inform monitoring of disease course or duration of fecal viral shedding during hospitalization. Because the abstract text is truncated and does not detail specific taxa or mechanisms, any therapeutic implications remain speculative and would need confirmation from the full results section.

What was studied?

The study used shotgun metagenomic sequencing to compare the microbial communities of three ocular surface sites (meibum, eyelid skin, and conjunctiva) between patients with meibomian gland dysfunction (MGD) and healthy controls. The goal was to characterize taxonomic composition, resident pathogens, and functional and virulence features associated with MGD.

Who was studied?

The cohort was 76 Chinese Han volunteers recruited at the Dry Eye Center of the Eye Hospital of Wenzhou Medical University, comprising 61 treatment-naive MGD patients and 15 healthy controls, sampled between April and September 2017. After quality control, 117 metagenome datasets were analyzed (58 meibum, 44 eyelid skin, and 15 conjunctiva), generated by whole-genome amplification and paired-end Illumina HiSeq shotgun sequencing (2 x 150 bp).

What were the most important findings?

The MGD meibum microbiome had lower community richness (chao1) than controls while diversity indices (Shannon, Simpson) were similar, and its significant taxonomic changes were largely shared with eyelid skin but not conjunctiva. MGD meibum carried fewer pathogens on average than controls (mean 13 vs 36, p = 0.0014), yet Campylobacter coli, Campylobacter jejuni, and Enterococcus faecium were strongly enriched in MGD meibum (positive rates of about 57%, 51%, and 47% versus 0% in controls, with abundance more than 16-fold higher). Functional profiling showed increased carbohydrate and lipid metabolism enzymes, a microbial capacity to degrade benzoate, and an approximately fivefold increase in the type IV secretion system virulence factor (p = 0.017).

What are the greatest implications of this study?

The authors conclude that MGD meibum contains distinct microbiota with stronger immune-evasive virulence, characterizing microbial community changes associated with MGD disease status. Because this is an observational case-control comparison, the results indicate association rather than causation, and the authors call for validation in larger and more geographically diverse populations.

What was studied?

The microbiota is the community of microorganisms that colonizes the oral cavity, respiratory tract, and gut of multicellular organisms. The microbiota exerts manifold physiological and pathological impacts on the organism it inhabits. A growing body of attention is being paid to host-microbiota interplay, which is highly relevant to the development of carcinogenesis. Adenomatous polyps are considered a common hallmark of colorectal cancer, the second leading cause of carcinogenesis-mediated death worldwide. In this study, we examined the relevance between targeted operational taxonomic units and colonic polyps using short- and long-read sequencing platforms. The gut microbiota was assessed in 132 clinical subjects, including 53 healthy participants, 36 patients with occult blood in the gut, and 43 cases with adenomatous polyps. An elevation in the relative abundance of Klebsiella pneumonia, Fusobacterium varium, and Fusobacterium mortiferum was identified in patients with adenomatous polyps compared with the other groups using long-read sequencing workflow. In contrast, the relatively high abundances of Blautia luti, Bacteroides plebeius, and Prevotella copri were characterized in the healthy groups. The diversities in gut microbiota communities were similar in all recruited samples. These results indicated that alterations in gut microbiota were characteristic of participants with adenomatous polyps, which might be relevant to the further development of CRC. These findings provide a potential contribution to the early prediction and interception of CRC occurrence.

What was studied?

This study examined how mode of delivery affects the earliest colonization of the infant gut microbiota during the neonatal period (up to one month of age) and into infancy. The researchers used longitudinal sampling combined with whole-genome shotgun metagenomic analysis to track which microbial strains and species established themselves in newborns over time. They specifically compared babies born by caesarean section to those born vaginally, and also looked at the effects of maternal antibiotic prophylaxis and breastfeeding status during the neonatal window.

Who was studied?

The cohort comprised 596 full-term babies born in UK hospitals, from whom 1,679 gut microbiota samples were collected at multiple time points during the neonatal period and later in infancy. For a subset of these infant-mother pairs, matched maternal samples were also collected, totaling 175 mothers paired with 178 babies. This gave the study both a large infant sample size and a smaller nested set of mother-infant pairs for tracking strain transmission.

What were the most important findings?

Babies delivered by caesarean section showed disrupted transmission of maternal Bacteroides strains, meaning these commensal organisms were less successfully passed from mother to infant compared to vaginal delivery. Caesarean-born infants also showed high-level colonization by opportunistic pathogens associated with the hospital environment, including Enterococcus, Enterobacter, and Klebsiella species. These same disruptions, though to a lesser extent, were also observed in vaginally delivered babies whose mothers received antibiotic prophylaxis and in infants who were not breastfed during the neonatal period.

What are the greatest implications of this study?

The findings suggest that both caesarean delivery and antibiotic exposure around birth can independently disrupt the normal, low-risk colonization of the infant gut by maternal commensal strains. This disruption opens the door for opportunistic, hospital-associated pathogens to establish themselves early in life instead. Because early gut microbiota composition has been linked to later childhood and lifelong disease risk, these results point to birth mode, antibiotic use, and breastfeeding as modifiable factors that could be targeted to support healthier early microbiome establishment.

What was studied?

Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 axis induce sustained clinical responses in a sizable minority of cancer patients. We found that primary resistance to ICIs can be attributed to abnormal gut microbiome composition. Antibiotics inhibited the clinical benefit of ICIs in patients with advanced cancer. Fecal microbiota transplantation (FMT) from cancer patients who responded to ICIs into germ-free or antibiotic-treated mice ameliorated the antitumor effects of PD-1 blockade, whereas FMT from nonresponding patients failed to do so. Metagenomics of patient stool samples at diagnosis revealed correlations between clinical responses to ICIs and the relative abundance of Akkermansia muciniphila Oral supplementation with A. muciniphila after FMT with nonresponder feces restored the efficacy of PD-1 blockade in an interleukin-12-dependent manner by increasing the recruitment of CCR9+CXCR3+CD4+ T lymphocytes into mouse tumor beds.

What was studied?

Anti-PD-1-based immunotherapy has had a major impact on cancer treatment but has only benefited a subset of patients. Among the variables that could contribute to interpatient heterogeneity is differential composition of the patients' microbiome, which has been shown to affect antitumor immunity and immunotherapy efficacy in preclinical mouse models. We analyzed baseline stool samples from metastatic melanoma patients before immunotherapy treatment, through an integration of 16S ribosomal RNA gene sequencing, metagenomic shotgun sequencing, and quantitative polymerase chain reaction for selected bacteria. A significant association was observed between commensal microbial composition and clinical response. Bacterial species more abundant in responders included Bifidobacterium longum, Collinsella aerofaciens, and Enterococcus faecium. Reconstitution of germ-free mice with fecal material from responding patients could lead to improved tumor control, augmented T cell responses, and greater efficacy of anti-PD-L1 therapy. Our results suggest that the commensal microbiome may have a mechanistic impact on antitumor immunity in human cancer patients.

What was studied?

It is well known that the microbiota of high-fat (HF) diet-induced obese mice differs from that of lean mice, but to what extent, this difference reflects the obese state or the diet is unclear. To dissociate changes in the gut microbiota associated with high HF feeding from those associated with obesity, we took advantage of the different susceptibility of C57BL/6JBomTac (BL6) and 129S6/SvEvTac (Sv129) mice to diet-induced obesity and of their different responses to inhibition of cyclooxygenase (COX) activity, where inhibition of COX activity in BL6 mice prevents HF diet-induced obesity, but in Sv129 mice accentuates obesity.

What were the most important findings?

Using HiSeq-based whole genome sequencing, we identified taxonomic and functional differences in the gut microbiota of the two mouse strains fed regular low-fat or HF diets with or without supplementation with the COX-inhibitor, indomethacin. HF feeding rather than obesity development led to distinct changes in the gut microbiota. We observed a robust increase in alpha diversity, gene count, abundance of genera known to be butyrate producers, and abundance of genes involved in butyrate production in Sv129 mice compared to BL6 mice fed either a LF or a HF diet. Conversely, the abundance of genes involved in propionate metabolism, associated with increased energy harvest, was higher in BL6 mice than Sv129 mice.

What are the greatest implications of this study?

The changes in the composition of the gut microbiota were predominantly driven by high-fat feeding rather than reflecting the obese state of the mice. Differences in the abundance of butyrate and propionate producing bacteria in the gut may at least in part contribute to the observed differences in obesity propensity in Sv129 and BL6 mice.

What was studied?

Cross-sectional studies suggested that obesity is promoted by the gut microbiota. However, longitudinal data on taxonomic and functional changes in the gut microbiota of obese patients are scarce. The aim of this work is to study microbiota changes in the course of weight loss therapy and the following year in obese individuals with or without co-morbidities, and to asses a possible predictive value of the gut microbiota with regard to weight loss maintenance.

Who was studied?

Sixteen adult patients, who followed a 52-week weight-loss program comprising low calorie diet, exercise and behavioral therapy, were selected according to their weight-loss course. Over two years, anthropometric and metabolic parameters were assessed and microbiota from stool samples was functionally and taxonomically analyzed using DNA shotgun sequencing.

What were the most important findings?

Overall the microbiota responded to the dietetic and lifestyle intervention but tended to return to the initial situation both at the taxonomical and functional level at the end of the intervention after one year, except for an increase in Akkermansia abundance which remained stable over two years (12.7x103 counts, 95%CI: 322-25100 at month 0; 141x103 counts, 95%CI: 49-233x103 at month 24; p = 0.005). The Firmicutes/Bacteroidetes ratio was higher in obese subjects with metabolic syndrome (0.64, 95%CI: 0.34-0.95) than in the "healthy obese" (0.27, 95%CI: 0.08-0.45, p = 0.04). Participants, who succeeded in losing their weight consistently over the two years, had at baseline a microbiota enriched in Alistipes, Pseudoflavonifractor and enzymes of the oxidative phosphorylation pathway compared to patients who were less successful in weight reduction.

What are the greatest implications of this study?

Successful weight reduction in the obese is accompanied with increased Akkermansia numbers in feces. Metabolic co-morbidities are associated with a higher Firmicutes/Bacteroidetes ratio. Most interestingly, microbiota differences might allow discrimination between successful and unsuccessful weight loss prior to intervention.

What was studied?

Evidence suggests a correlation between the gut microbiota composition and weight loss caused by caloric restriction. Laparoscopic sleeve gastrectomy (LSG), a surgical intervention for obesity, is classified as predominantly restrictive procedure. In this study we investigated functional weight loss mechanisms with regard to gut microbial changes and energy harvest induced by LSG and a very low calorie diet in ten obese subjects (n = 5 per group) demonstrating identical weight loss during a follow-up period of six months. For gut microbiome analysis next generation sequencing was performed and faeces were analyzed for targeted metabolomics. The energy-reabsorbing potential of the gut microbiota decreased following LSG, indicated by the Bacteroidetes/Firmicutes ratio, but increased during diet. Changes in butyrate-producing bacterial species were responsible for the Firmicutes changes in both groups. No alteration of faecal butyrate was observed, but the microbial capacity for butyrate fermentation decreased following LSG and increased following dietetic intervention. LSG resulted in enhanced faecal excretion of nonesterified fatty acids and bile acids. LSG, but not dietetic restriction, improved the obesity-associated gut microbiota composition towards a lean microbiome phenotype. Moreover, LSG increased malabsorption due to loss in energy-rich faecal substrates and impairment of bile acid circulation. This trial is registered with ClinicalTrials.gov NCT01344525.

What was studied?

IBS is a prevalent functional gastrointestinal disorder, in which the microbiota has been demonstrated to play a role. An increasing number of studies have suggested how probiotics may alleviate IBS symptoms and several mechanisms of action have been proposed.   In the present study we characterized the intestinal microbiota of 19 subjects suffering from diagnosed IBS using a fully validated High Taxonomic Fingerprint Microbiota Array (HTF-Microbi.Array). We demonstrated that the IBS microbiota is different from that of healthy individuals due to an unbalance in a number of commensal species, with an increase in relative abundance of lactobacilli, B. cereus and B. clausii, bifidobacteria, Clostridium cluster IX and E. rectale, and a decrease in abundance of Bacteroides/Prevotella group and Veillonella genus. Additionally, we demonstrated that some bacterial groups of the human intestinal microbiota, recently defined as pathobionts, are increased in concentration in the IBS microbiota. Furthermore, we aimed at investigating if the daily administration of a novel probiotic yogurt containing B. animalis subsp lactis Bb12 and K. marxianus B0399, recently demonstrated to have beneficial effects in the management of IBS symptoms, could impact on the biostructure of IBS microbiota, modulating its composition to counteract putative dysbiosis found in IBS subjects. Notably, we demonstrated that the beneficial effects associated to the probiotic preparation are not related to significant modifications in the composition of the human intestinal microbiota.

What was studied?

Only the title of this study was available, not the abstract, so this summary is necessarily limited. The title indicates the researchers examined the metabolic genes of the gut microbiome in patients who have an ileo-anal pouch. The stated focus was on whether this metabolic-gene dysbiosis resembles the pattern seen in Crohn's disease.

Who was studied?

The title identifies the population as patients with an ileo-anal pouch, a surgically constructed reservoir typically created after removal of the colon and rectum. No sample size, recruitment setting, or additional demographic details are given in the title. Without an abstract, the exact cohort characteristics cannot be honestly specified beyond this population description.

What were the most important findings?

The title states that the gut microbiomes of ileo-anal pouch patients show dysbiosis in metabolic genes. It further states that this pattern of dysbiosis resembles what is observed in Crohn's disease. No specific genes, pathways, taxa, or magnitude of change are provided, since only the title was available.

What are the greatest implications of this study?

If metabolic-gene dysbiosis in ileo-anal pouches mirrors Crohn's disease, this suggests a shared functional microbial signature across these two gut conditions. This could support using Crohn's disease-associated metabolic markers to help understand or monitor pouch dysfunction. Because only the title was available, these implications are inferred and would need confirmation from the full study.