Differences In Microbiota Composition Research Articles

Microbiota composition of an autochthonous Krškopolje pig breed reared in two different organic production systems

It has been shown that different production systems (conventional vs. pasture-raised pigs) and co-rearing of pigs with other livestock influence the gut microbiota composition in pigs. In this study, two independent trials were conducted to investigate the 16S fecal microbiota of the autochthonous Krškopolje pig. In each trial, three study groups were analyzed: (i) pasture-raised pigs cohabiting with small ruminants (group L1, farm 1), (ii) indoor-raised pigs without contact with other farm animals (group L2, farm 2) and fed the same commercial organic feed as the other two groups, and (iii) pasture-raised pigs cohabiting with cattle (group L3, farm 2). The pigs were sampled four times during the grower-finisher period, corresponding to the different seasons. A total of 18 and 22 pigs were included in trials 1 and 2, respectively. Alpha diversity was comparable between the study groups and the pigs of different age categories. The two predominant bacterial phyla in all three groups were Bacteroidota and Firmicutes. Significant differences in microbiota composition were found between pigs of different age categories in both trials (nonparametric MANOVA, p < 0.008). The microbiota composition of pigs from group L1 was significantly different from that of pigs from groups L2 and L3, whereas groups L2 and L3 tended to be more similar in both trials. The present results indicate that the trial and the farm of origin have a significant influence on the pig gut microbiota, and that their influence is more pronounced than that of the housing system.

Cigarette smoke-induced disordered microbiota aggravates the severity of influenza A virus infection.

Cigarette smoke (CS) promotes the development of chronic pulmonary disease and has been associated with increased risk for influenza-related illness. Here, we directly addressed the impact of CS disordered microbiota on the severity of influenza A virus (IAV) infection. Specific and opportunistic pathogen-free (SOPF) C57BL/6J mice were exposed to CS or room air (RA) for 5.5 months. Each exposed mouse was then cohoused with a group of recipient germ-free (GF) mice for 1 month for microbial transfer. Colonized GF mice were then infected intranasally with IAV and disease development was monitored. Upper and lower airway and fecal microbiota were longitudinally investigated by 16S rRNA gene sequencing and bacterial cultures in donor and recipient mice. The bacterial family Streptococcaceae accounted for the largest difference between CS- and RA-exposed microbiota in the oropharynx. Analysis of the oropharynx and fecal microbiota indicated an efficient transfer to coprophagic recipient mice, which replicated the differences in microbiota composition observed in donor mice. Subsequent IAV infection revealed significantly higher weight loss for CS microbiota recipient mice at 8-10 days post infection (dpi) compared to control recipient mice. In addition, H1N1 infection inflicted substantial changes in the microbiota composition, especially at days 4 and 8 after infection. In conclusion, mice with a CS-associated microbiota suffer from higher disease severity upon IAV infection compared to mice colonized with a normal SOPF microbiota. Our data suggest that independently of CS exposure and concomitant structural lung damage, microbial distortion due to CS exposure may impact the severity of IAV disease course.IMPORTANCEIt has been reported that chronic exposure to CS is associated with a disordered microbiota composition. In this study, we colonized germ-free (GF) mice with the microbiota from SOPF mice which were chronically exposed to CS or RA. This allowed disentangling the effect of the disordered microbiota from the immune-modulating effects of actual CS exposure. We observed a successful transfer of the microbiotas after cohousing including specific microbiota differences induced by CS exposure in formerly GF mice, which were never exposed to CS. We then investigated the effects of IAV infection on the disease course and microbiotas of formerly GF mice. We found that mice with CS-associated microbiota reveal worse disease course compared to the control group. We hypothesize that CS-induced disordering of the microbiota may, indeed, impact the severity of influenza A disease.

Association of Gut Microbiota Composition with Stunting Incidence in Children under Five in Jakarta Slums.

Stunting can be linked to various factors, one of which is dysbiosis. This study aims to analyze the microbiota composition and related contributing factors of stunted and non-stunted children in the slum areas of Jakarta. The subjects in this study included 21 stunted (HAZ ≤ -2SD) and 21 non-stunted children (-2SD ≤ HAZ ≤ 3SD) aged 2-5 years. Microbiota analysis was performed by extracting DNA from the subjects' feces and then via 16S rRNA sequencing using next-generation sequencing (NGS). The results of this study showed that in stunted children, the abundance of Mitsuokella (24,469 OTUs), Alloprevotella (23,952 OTUs), and Providencia alcalifaciens (861 OTUs) was higher, while in non-stunted children, that of Blautia (29,755 OTUs), Lachnospiraceae (6134 OTUs), Bilophila (12,417 OTUs), Monoglobus (484 OTUs), Akkermansia muciniphila (1116 OTUs), Odoribacter splanchnicus (42,993 OTUs), and Bacteroides clarus (8900 OTUs) was higher. Differences in microbiota composition in the two groups were influenced by nutrient intake, birth history, breastfeeding history, handwashing habits before eating, drinking water sources, and water sources for other activities. This study highlights that stunted children have a significantly different gut microbiota composition compared to non-stunted children, with higher levels of pathogenic bacteria and lower levels of beneficial bacteria. Future research should focus on interventions that can improve the gut microbiota composition to prevent stunting in children.

Effect of host breeds on gut microbiome and fecal metabolome in commercial pigs

BackgroundGut microbial composition and its metabolites are crucial for livestock production performance. Metabolite profiles from autopsied biospecimens provide vital information on the basic mechanisms that affect the overall health and production traits in livestock animals. However, the role of the host breed in the gut microbiome and fecal metabolome of commercial pigs remains unclear. In this work, differences in microbiota composition among three commercial pig breeds Duroc, Yorkshire, and Landrace were measured by 16S rRNA gene sequencing. Fecal metabolite compositions of the three pig breeds were detected using untargeted metabolomics.ResultsThere were significant differences in the gut microbiomes of the three species, indicating that host breed affects the diversity and structure of gut microbiota. Several breed-associated microorganisms were identified at different taxonomic levels. Notely, most microbial taxa were annotated as Lactobacillacea, Muribaculaceae, and Oscillospiraceae. Several bacteria, including Lactobacillus, Subdoligranulum, Faecalibacterium, Oscillospira, Oscillospiraceae_UCG-002, and Christensenellaceae_R-7_group, could be considered as biomarkers for improving the backfat thickness (BF) for commercial pigs. Additionally, KEGG analysis of gut microbiota further revealed that arginine biosynthesis, pyruvate metabolism, and fatty acid biosynthesis varied greatly among pig breeds. Multiple gut bacterial metabolites (e.g., spermidine, estradiol, and palmitic acid) were identified as breed-associated. Mediation analysis ultimately revealed the cross-talk among gut microbiota, metabolites, and BF thickness, proclaiming that the microbial and metabolic biomarkers identified in this study could be used as biomarkers for improving BF phenotype.ConclusionsThis work provides vital insights into breed effects on gut microbiota and metabolite compositions of commercial pigs and uncovers potential biomarkers that are significant for pig breed improvement.

Gut Microbiota Diversity of Local Egyptian Cattle Managed in Different Ecosystems.

The animal gastrointestinal tract contains a complex microbiome whose composition ultimately reflects the co-evolution of microorganisms with their animal host and their host's environment. This study aimed to gain insights into the adaptation of the microbiota of local Egyptian cattle to three different ecosystems (Upper Egypt, Middle Egypt, and Lower Egypt) distributed across 11 governorates (with an average of 12 animals per governorate) using amplicon sequencing. We analyzed the microbiota from 136 fecal samples of local Egyptian cattle through a 16S rRNA gene sequencing approach to better understand the fecal microbial diversity of this breed which developed under different ecosystems. An alpha diversity analysis showed that the fecal microbiota of the Egyptian cattle was not significantly diverse across areas, seasons, sexes, or farm types. Meanwhile, microbiota data revealed significant differences in richness among age groups (p = 0.0018). The microbial community differed significantly in the distribution of its relative abundance rather than in richness across different ecosystems. The taxonomic analysis of the reads identified Firmicutes and Actinobacteriota as the dominant phyla, accounting for over 93% of the total bacterial community in Egyptian cattle. Middle Egypt exhibited a different microbial community composition compared to Upper and Lower Egypt, with a significantly higher abundance of Firmicutes and Euryarchaeota and a lower abundance of Actinobacteriota in this region than the other two ecosystems. Additionally, Middle Egypt had a significantly higher relative abundance of the Methanobacteriaceae family and the Methanobrevibacter genera than Lower and Upper Egypt. These results suggest a difference in the adaptation of the fecal microbial communities of Egyptian cattle raised in Middle Egypt. At the genus level, eleven genera were significantly different among the three ecosystems including Bacillus, DNF00809, Kandleria, Lachnospiraceae_NK3A20_group, Methanobrevibacter, Mogibacterium, Olsenella, Paeniclostridium, Romboutsia, Turicibacter, and UCG-005. These significant differences in microbiota composition may impact the animal's adaptation to varied environments.

Evolutive Study of Dietary Aspects and Intestinal Microbiota of Pediatric Cohort with Cow's Milk Protein Allergy.

One of the most common food allergies in the pediatric population is allergy to cow's milk protein (CMPA). Treatment consists of avoiding cow's milk proteins in lactating mothers and/or using therapeutic formulas based on hydrolysates or vegetable formulas. In infants with CMPA at diagnosis, a different gut microbial profile has been found compared to healthy children, with a reduction in beneficial bacteria. The aim of this study was to evaluate changes in the gut microbiota profile and its metabolites, dietary patterns and anthropometric variables in a pediatric cohort with CMPA after six months on a restrictive diet compared to healthy controls. In total, 21 patients diagnosed with CMPA and a control group of 24 healthy infants participated in this study. The fecal microbiota of all participants were investigated by metataxonomic analysis of 16S rDNA amplicons, and fecal short-chain fatty acids were measured by gas chromatography. Epidemiological assessment and dietary questionnaires were carried out for both groups. Regarding growth, no significant differences were found, but differences in dietary intake of some macro- and micronutrients were observed. Patients who were breastfed at six months had higher bifidobacteria and lipid intakes than patients fed with hydrolyzed formulas. Although the growth of CMPA infants fed with therapeutic formula is similar to breastfed CMPA infants, there are differences in microbiota composition and macronutrient intake that underline the importance of continued breastfeeding in CMPA cases.

Examination of sex-specific interactions between gut microbiota and host metabolism after 12-week combined polyphenol supplementation in individuals with overweight or obesity

ABSTRACT Polyphenols exert beneficial effects on host metabolism, which may be mediated by the gut microbiota. We investigated sex-specific differences in microbiota composition and interactions with cardiometabolic parameters after polyphenol supplementation in individuals with overweight/obesity. In a double-blind, randomized, placebo-controlled trial, 19 women and 18 men with normal glucose tolerance and body mass index >25 kg/m2 received epigallocatechin-3-gallate and resveratrol (EGCG+RES, 282 + 80 mg/d) or placebo supplements for 12 weeks. Fecal microbiota composition (16S rRNA gene amplicon sequencing, V3-V4 region), in vivo whole-body fat oxidation (indirect calorimetry), and mitochondrial respiration in permeabilized skeletal muscle fibers (SkM-Ox; ex vivo respirometry) were determined pre- and post-intervention. Overall, EGCG+RES supplementation did not affect gut microbiota composition. Akkermansia, Ruminococcaceae UCG-002, Subdoligranulum, and Lachnospiraceae UCG-004 were more abundant, while Veillonella, Tyzzerella 4, Clostridium innocuum group, Ruminococcus gnavus group, Escherichia-Shigella, and an uncultured Ruminococcaceae family genus were less abundant in women compared to men. In women, only baseline Eubacterium ventriosum group abundance correlated with EGCG+RES-induced changes in SkM-Ox. In men, low Dorea, Barnsiella, Anaerotruncus, Ruminococcus, Subdoligranulum, Coprococcus, Eubacterium ventriosum group, Ruminococcaceae UCG-003, and a Ruminococcaceae family genus abundance, and high Blautia abundance at baseline were associated with improvements in SkM-Ox. Changes in whole-body fat oxidation were not associated with gut microbiota features. We conclude that baseline microbiota composition predicts changes in SkM-Ox as a result of EGCG+RES supplementation in men but not in women. Men may be more prone to diet-induced, gut microbiota-related improvements in cardiometabolic health. These sex-differences should be further investigated in future precision-based intervention studies.

Exploring the Impact of the Liver-Intestine-Brain Axis on Brain Function in Non-Alcoholic Fatty Liver Disease

This study investigates the molecular complexities of Non-alcoholic Fatty Liver Disease (NAFLD)-induced brain dysfunction, with a focus on the liver-intestine-brain axis and potential therapeutic interventions. The main objectives include understanding critical microbiota shifts in NAFLD, exploring altered metabolites, and identifying key regulatory molecules influencing brain function. The methods employed encompassed 16S rRNA sequencing to scrutinize stool microbiota in NAFLD patients and healthy individuals, non-targeted metabolomics using LC-MS to uncover elevated levels of deoxycholic acid (DCA) in NAFLD mice, and single-cell RNA sequencing to pinpoint the pivotal gene Hpgd in microglial cells and its downstream janus kinase 2/signal transducer and activator of transcription 3 (Jak2/Stat3) signaling pathway. Behavioral changes and brain function were assessed in NAFLD mice with and without Fecal Microbiota Transplantation (FMT) treatment, utilizing various assays and analyses. The results revealed significant differences in microbiota composition, with increased levels of Bacteroides in NAFLD patients. Additionally, elevated DCA levels were observed in NAFLD mice, and FMT treatment demonstrated efficacy in ameliorating liver function and brain dysfunction. Hpgd inhibition by DCA activated the Jak2/Stat3 pathway in microglial cells, leading to inflammatory activation, inhibition of mitochondrial autophagy, induction of neuronal apoptosis, and reduction in neuronal action potentials. This study elucidates the intricate molecular mechanisms underlying the liver-gut-brain axis in NAFLD, and the identification of increased DCA and the impact of Jak2/Stat3 signaling on microglial cells highlight potential therapeutic targets for addressing NAFLD-induced brain dysfunction.

Transcriptomic and Metabolomic Correlates of Increased Colonic Permeability in Postinfection Irritable Bowel Syndrome

Background and aimPost-infection irritable bowel syndrome (PI-IBS) is well-known epidemiologically; however, its physiological and molecular characteristics are not well studied. We aimed to determine the physiological phenotypes, colonic transcriptome, fecal microbiome, and metabolome in PI-IBS. MethodsFifty-one Rome III Campylobacter PI-IBS patients and 39 healthy volunteers (HV) were enrolled. Participants completed questionnaires, in vivo intestinal permeability, gastrointestinal transit, and rectal sensation. Fecal samples were collected for shotgun metagenomics, untargeted metabolomics, and sigmoid colonic biopsies for bulk RNAseq. Differential gene expression, differences in microbiota composition and metabolite abundance were determined. Gene and metabolite clusters were identified via weighted gene correlation network analysis and correlations with clinical and physiological parameters determined. ResultsPI-IBS (59% F, 46±2 yrs.) and HV (64% F, 42±2 yrs.) demographics were comparable. Mean IBS-symptom severity score was 227; 94% were non-constipation. 2-24h lactulose excretion was increased in PI-IBS, suggesting increased colonic permeability (4.4±0.5 mg vs. 2.6±0.3 mg, p=0.01). Colonic transit and sensory thresholds were similar between the two groups. Overall, expression of 2036 mucosal genes and 223 fecal metabolites were different, with changes more prominent in females. Fecal N-acetylputrescine was increased in PI-IBS and associated with colonic permeability, worse diarrhea, and negatively correlated with abundance of Collinsella aerofaciens. Histamine and N-acetyl histamine positively associated with 2-24 hr lactulose excretion. Eight weighted gene coexpression modules significantly correlated with phenotypes (sex, stool frequency, colonic permeability, transit). ConclusionsCampylobacter PI-IBS patients demonstrate higher colonic permeability which associated with changes in polyamine and histamine metabolites. Female patients demonstrated greater molecular changes.

Dietary protein affects tissue accumulation of mercury and induces hepatic Phase I and Phase II enzyme expression after co-exposure with methylmercury in mice

Methylmercury (MeHg) is a ubiquitous environmental contaminant, well known for its neurotoxic effects. MeHg can interact with several nutrients in the diet and affect nutrient metabolism, however the interaction between MeHg and dietary proteins has not been thoroughly investigated. Male BALB/c mice were fed diets based on either casein, cod or chicken as protein sources, which were or were not spiked with MeHg (3.5 mg Hg kg−1). Following 13 weeks of dietary exposure to MeHg, the animals accumulated mercury in a varying degree depending on the diet, where the levels of mercury were highest in the mice fed casein and MeHg, lower in mice fed cod and MeHg, and lowest in mice fed chicken and MeHg in all tissues assessed. Assessment of gut microbiota revealed differences in microbiota composition based on the different protein sources. However, the introduction of MeHg eliminated this difference. Proteomic profiling of liver tissue uncovered the influence of the dietary protein sources on a range of enzymes related to Phase I and Phase II detoxification mechanisms, suggesting an impact of the diet on MeHg metabolism and excretion. Also, enzymes linked to pathways including methionine and glycine betaine cycling, which in turn impact the production of glutathione, an important MeHg conjugation molecule, were up-regulated in mice fed chicken as dietary protein. Our findings indicate that dietary proteins can affect expression of hepatic enzymes that potentially influence MeHg metabolism and excretion, highlighting the relevance of considering the dietary composition in risk assessment of MeHg through dietary exposure.

Gut Dysbiosis in the First-Passed Meconium Microbiomes of Korean Preterm Infants Compared to Full-Term Neonates.

Since gestational age (GA) is an important factor influencing the presence of specific microbiomes, we aimed to characterize the core microbiomes of preterm infants compared to full-term (FT) infants. This study investigated the differences in microbiota composition between very preterm (VP), moderate-to-late preterm (MLP), and FT neonates by examining the core microbiomes of a large cohort of Korean neonates. Meconium samples from 310 neonates with a GA range of 22-40 weeks were collected, and 16S rRNA analyses were performed; 97 samples were obtained from the FT, 59 from the VP, and 154 from the MLP group. Firmicutes, Bacteroidetes, and Proteobacteria were the phylum-level core microbiomes. Infants born before 37 weeks showed a disruption in the core microbiomes. At the phylum level, the relative abundance of Bacteroidetes was positively (r = 0.177, p = 0.002) correlated with GA, while that of Proteobacteria was negatively (r = -0.116, p = 0.040) correlated with GA. At the genus level, the relative abundances of Bacteroides and Prevotella were positively correlated with GA (r = 0.157, p = 0.006; r = 0.160, p = 0.005). The meconium of preterm infants exhibited significantly lower α-diversities than that of FT infants. β-diversities did not appear to differ between the groups. Overall, these findings underscore the importance of GA in shaping the early gut microbiome.

Spatio-temporal dynamics of the human small intestinal microbiome and its response to a synbiotic

ABSTRACT Although fecal microbiota composition is considered to preserve relevant and representative information for distal colonic content, it is evident that it does not represent microbial communities inhabiting the small intestine. Nevertheless, studies investigating the human small intestinal microbiome and its response to dietary intervention are still scarce. The current study investigated the spatio-temporal dynamics of the small intestinal microbiome within a day and over 20 days, as well as its responses to a 14-day synbiotic or placebo control supplementation in 20 healthy subjects. Microbial composition and metabolome of luminal content of duodenum, jejunum, proximal ileum and feces differed significantly from each other. Additionally, differences in microbiota composition along the small intestine were most pronounced in the morning after overnight fasting, whereas differences in composition were not always measurable around noon or in the afternoon. Although overall small intestinal microbiota composition did not change significantly within 1 day and during 20 days, remarkable, individual-specific temporal dynamics were observed in individual subjects. In response to the synbiotic supplementation, only the microbial diversity in jejunum changed significantly. Increased metabolic activity of probiotic strains during intestinal passage, as assessed by metatranscriptome analysis, was not observed. Nevertheless, synbiotic supplementation led to a short-term spike in the relative abundance of genera included in the product in the small intestine approximately 2 hours post-ingestion. Collectively, small intestinal microbiota are highly dynamic. Ingested probiotic bacteria could lead to a transient spike in the relative abundance of corresponding genera and ASVs, suggesting their passage through the entire gastrointestinal tract. This study was registered to http://www.clinicaltrials.gov, NCT02018900.

L. plantarum and L. casei synergistically mitigate Gastro-Intestinal Acute Radiation Syndrome (GI-ARS)

Introduction: Incidental or accidental acute exposure to ionizing radiation causes radiation toxicity, for which there are no known medical countermeasures (MCMs). Ionizing radiation alters host gut epithelium as well as the gut microbiome. We sought to investigate if radiation induced gut dysbiosis occurred as a result of depletion of gut-protective bacteria, and if probiotic supplementation of such bacteria could help mitigate GI-ARS post ionizing radiation exposure. Methods: Adult C57BL/6 mice were subjected to total body irradiation, and a defined concentration of probiotics (either individually or combined) were given 24 h after radiation exposure. Mice were sacrificed 24 hours post treatment (i.e., 48 h post irradiation). Vascular-to-luminal flux of FITC-inulin was measured to evaluate intestinal mucosal permeability and endotoxemia by measuring plasma lipopolysaccharide. Gut microbiota was analyzed by 16S rRNA sequencing. Intestinal epithelial junctions were analyzed by immunofluorescence confocal microscopy and mucosal inflammatory response by RT-PCR for cytokine expression. Systemic inflammation was evaluated by ELISA for plasma cytokines. Results and conclusion: Our data show that radiation altered the taxonomic composition of the microbiota compared to age-matched sham treated mice. Shannon index analysis showed a significant decrease in α-diversity in irradiated mice. Bray-Curtis analysis indicated significant differences in microbiota composition between Sham and IR groups. E. coli abundance was increased whereas Lactobacillus abundance was decreased, particularly L. plantarum and L. casei. Probiotic supplementation with individual Lactobacillus species each mitigated radiation induced intestinal barrier dysfunction, gut specific as well as systemic inflammatory cytokine expression and endotoxemia. Our preliminary data further indicates that L. plantarum affects Epidermal Growth Factor Receptor (EGFR)-mediated signaling whereas L. casei was EGFR-independent. Interestingly, combined supplementation in a 1:1 ratio further enhanced recovery compared to adding the individual effects. Individual supplementation of L. plantarum and L. casei to irradiated mice reduced intestinal (ileal) permeability by 2-fold and 3-fold respectively, whereas combined supplementation reduced ileal permeability almost 8-fold compared to irradiated but untreated mice. This data indicates that L. plantarum and L. casei mitigate GI-ARS by distinct cellular mechanisms. Furthermore, data show that a mixture of these probiotic species is more effective in radio-mitigation than individually. Further mechanistic analysis will be required to identify cross-talking targets between mechanisms of these probiotics and synergistic radio-mitigation. In conclusion, Lactobacillus species are potential MCMs for the treatment of GI-ARS. Funding acknowledgements: NIH/NIAID, UO1-AI170019, UO1-AI172991. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Possible link between colonization of the gastrointestinal tract by Citrobacter rodentium in C57BL/6 mice and microbiota composition.

Colonization resistance, conferred by the host's microbiota through both direct and indirect protective actions, serves to protect the host from enteric infections. Here, we identified the specific members of the gut microbiota that impact gastrointestinal colonization by Citrobacter rodentium, a murine pathogen causing colonic crypt hyperplasia. The gut colonization levels of C. rodentium in C57BL/6 mice varied among breeding facilities, probably due to differences in microbiota composition. A comprehensive analysis of the microbiota revealed that specific members of the microbiota may influence gut colonization by C. rodentium, thus providing a potential link between the two.

Microbial Profiles in Oral Lichen Planus: Comparisons with Healthy Controls and Erosive vs. Non-Erosive Subtypes.

Recent studies have begun exploring the potential involvement of microbiota in the pathogenesis of oral lichen planus (OLP), yet comprehensive investigations remain limited. Hence, this study aimed to compare the microbial profiles in saliva samples obtained from patients with OLP against those from healthy controls (HC), along with a comparison between erosive (E) and non-erosive (NE) OLP patients. Saliva samples were collected from 60 OLP patients (E: n = 25, NE: n = 35) and 30 HC individuals. Analysis revealed no significant differences in alpha diversity, as assessed by the Chao1 and Shannon index, across the three groups. However, Bray-Curtis distance analysis indicated a significant disparity in microbiome composition distribution between HC and E-OLP, as well as HC and NE-OLP groups. The six most abundant phyla observed across the groups were Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Fusobacteria, and Saccharibacteria (TM7). Notably, OLP groups exhibited a higher prevalence of Bacteroidetes. Prevotella emerged as the predominant genus in the OLP groups, while Capnocytophaga showed a relatively higher prevalence in E-OLP compared to NE-OLP. This study's findings indicate a notable difference in microbiota composition between HC and patients with OLP. Additionally, differences in the microbiome were identified between the E-OLP and NE-OLP groups. The increase in the proportion of certain bacterial species in the oral microbiome suggests that they may exacerbate the inflammatory response and act as antigens for OLP.

Saliva and tongue microbiota in burning mouth syndrome: An exploratory study of potential roles.

Burning mouth syndrome (BMS) is a chronic orofacial pain disorder with unclear etiology, in which the tongue is most commonly affected. This study aims to provide implication of the possible relationship between oral microbiota and the pathogenesis of BMS. Saliva and tongue swabs of 15 primary BMS patients and 10 healthy controls were collected and assessed by 16S rRNA gene amplicon sequencing. The microbiota compositions were compared and bioinformatic analysis was conducted. Differences in microbiota compositions between BMS patients and healthy controls were revealed in both saliva and tongue samples. In saliva, Streptococcus, Rothia, and Neisseria were the predominant genus at the taxonomic level in BMS patients. In tongue samples, Prevotella, Streptococcus, and Neisseria were the dominant genus at thetaxonomic level in BMS patients. LEfSe analysis and linear discriminant analysis score showed that Actinobacteria were the predominant phylum in saliva, and Selenomonas were enriched in the dorsum of the tongue of BMS patients. This study for the first-time reported saliva and tongue microbiota profiles were distinguished from that of healthy controls, indicating a necessity for further research on the possible relationship between oral microbes and the pathogenesis of BMS.

Opportunistic pathogens increased and probiotics or short-chain fatty acid-producing bacteria decreased in the intestinal microbiota of pneumonia inpatients during SARS-CoV-2 Omicron variant epidemic.

The global pandemic of COVID-19 has been over four years, and the role of intestinal microbiota in the occurrence and development of COVID-19 needs to be further clarified. During the outbreak of SARS-CoV-2 Omicron variant in China, we analyzed the intestinal microbiome in fecal samples from inpatients with pneumonia and normal individuals in January 2023. The microbiota composition, alpha diversity, beta diversity, differential microbial community, co-occurrence networks, and functional abundance were analyzed. The results showed significant differences in microbiota composition between the two groups. In pneumonia group, the abundance of Bifidobacterium, Blautia, Clostridium, and Coprococcus decreased, while the abundance of Enterococcus, Lactobacillus, and Megamonas increased. Through LEfSe analysis, 37 marker microbiota were identified in pneumonia group. Co-occurrence network analysis found that Lachnospiraceae was critical for the interaction of intestinal microbiota, and the anti-inflammatory bacteria Blautia was negatively correlated with the pro-inflammatory bacteria Ruminococcus. Functional prediction found the up-regulation of steroid biosynthesis, geraniol degradation, and mRNA surveillance pathway in pneumonia group. In conclusion, opportunistic pathogens increased and probiotics, or short-chain fatty acid-producing bacteria, decreased in the intestinal microbiota of pneumonia inpatients during the Omicron epidemic. Blautia could be used as a probiotic in the treatment of pneumonia patients in the future.

Development of non-alcoholic steatohepatitis is associated with gut microbiota but not with oxysterol enzymes CH25H, EBI2, or CYP7B1 in mice

Liver steatosis is the most frequent liver disorder and its advanced stage, non-alcoholic steatohepatitis (NASH), will soon become the main reason for liver fibrosis and cirrhosis. The “multiple hits hypothesis” suggests that progression from simple steatosis to NASH is triggered by multiple factors including the gut microbiota composition. The Epstein Barr virus induced gene 2 (EBI2) is a receptor for the oxysterol 7a, 25-dihydroxycholesterol synthesized by the enzymes CH25H and CYP7B1. EBI2 and its ligand control activation of immune cells in secondary lymphoid organs and the gut. Here we show a concurrent study of the microbial dysregulation and perturbation of the EBI2 axis in a mice model of NASH.We used mice with wildtype, or littermates with CH25H−/−, EBI2−/−, or CYP7B1−/− genotypes fed with a high-fat diet (HFD) containing high amounts of fat, cholesterol, and fructose for 20 weeks to induce liver steatosis and NASH. Fecal and small intestinal microbiota samples were collected, and microbiota signatures were compared according to genotype and NASH disease state.We found pronounced differences in microbiota composition of mice with HFD developing NASH compared to mice did not developing NASH. In mice with NASH, we identified significantly increased 33 taxa mainly belonging to the Clostridiales order and/ or the family, and significantly decreased 17 taxa. Using an Elastic Net algorithm, we suggest a microbiota signature that predicts NASH in animals with a HFD from the microbiota composition with moderate accuracy (area under the receiver operator characteristics curve = 0.64). In contrast, no microbiota differences regarding the studied genotypes (wildtype vs knock-out CH25H−/−, EBI2−/−, or CYP7B1−/−) were observed.In conclusion, our data confirm previous studies identifying the intestinal microbiota composition as a relevant marker for NASH pathogenesis. Further, no link of the EBI2 – oxysterol axis to the intestinal microbiota was detectable in the current study.

Identification of enterotype and its predictive value for patients with colorectal cancer

BackgroundGut microbiota dysbiosis involved in the pathogenesis of colorectal cancer (CRC). The characteristics of enterotypes in CRC development have not been determined.ObjectiveTo characterize the gut microbiota of healthy, adenoma, and CRC subjects based on enterotype.MethodsThe 16 S rRNA sequencing data from 315 newly sequenced individuals and three previously published datasets were collected, providing total data for 367 healthy, 320 adenomas, and 415 CRC subjects. Enterotypes were analyzed for all samples, and differences in microbiota composition across subjects with different disease states in each enterotype were determined. The predictive values of a random forest classifier based on enterotype in distinguishing healthy, adenoma, and CRC subjects were evaluated and validated.ResultsSubjects were classified into one of three enterotypes, namely, Bacteroide- (BA_E), Blautia- (BL_E), and Streptococcus- (S_E) dominated clusters. The taxonomic profiles of these three enterotypes differed among the healthy, adenoma, and CRC cohorts. BA_E group was enriched with Bacteroides and Blautia; BL_E group was enriched by Blautia and Coprococcus; S_E was enriched by Streptococcus and Ruminococcus. Relative abundances of these genera varying among the three human cohorts. In training and validation sets, the S_E cluster showed better performance in distinguishing among CRC patients, adenoma patients, and healthy controls, as well as between CRC and non-CRC individuals, than the other two clusters.ConclusionThis study provides the first evidence to indicate that changes in the microbial composition of enterotypes are associated with disease status, thereby highlighting the diagnostic potential of enterotypes in the treatment of adenoma and CRC.

Soil depths and microhabitats shape soil and root-associated bacterial and archaeal communities more than crop rotation in wheat

The plethora of microorganisms inhabiting the immediate vicinity of healthy root systems plays a pivotal role in facilitating optimal nutrient and water acquisition by plants. In this study, we investigated the soil microbial communities associated with wheat roots within distinct microhabitats, root-affected soil (RA), rhizosphere (RH), and rhizoplane (RP). These microhabitats were explored at five soil depths, and our investigation focused on wheat cultivated in a monoculture (WM) and wheat crop rotation (WR). Overall, there were significant differences in microbiota composition between WM and WR, although no difference in bacterial diversity was observed. Differentially abundant taxa between WM and WR were observed in all three microhabitats, emphasizing important insights on the localization of commonly associated bacteria to wheat roots. Comparing the microhabitats, RP exhibited the most dissimilar microbial composition between WM and WR. Taxa that were differentially abundant between WM and WR were observed in the three microhabitats. The high relative abundance of taxa belonging to the phylum Proteobacteria in the rhizoplane, such as Devosia, Pseudomonas, Shinella, and Sphingomonas, along with other genera, such as Pedobacter (Bacteroidota), Agromyces and Streptomyces (Actinobacteriota) highlight the recruitment of potentially beneficial bacterial taxa to the vicinity of the roots. Interestingly, these taxa were observed along the entire length of wheat roots, even at depths of up to 120 cm. The presence of specific taxa associated with wheat roots at all soil depths may be beneficial for coping with nutrient and water shortages, particularly under upcoming climate scenarios, where water may be a limiting factor for plant growth. This study provides valuable insights for designing management strategies to promote a diverse and healthy microbial community in wheat cropping systems, considering soil depth and microhabitats as key factors. Although, at this time, we cannot link specific bacterial taxa to yield reductions commonly observed in monocultural fields, we propose that some genera may enhance plant nutrient or water acquisition in rotation compared with monoculture. Advanced technologies, including functional analyses and culturomics, may further enhance our understanding of the ecological roles played by these microbes and their potential applications in sustainable agriculture.