Abundance Of Several Bacterial Taxa Research Articles

Precision Glycan Supplementation Improves Gut Microbiota Diversity, Performance, and Disease Outbreak Resistance in Broiler Chickens.

The poultry industry contributes significantly to the global meat industry but faces many production challenges like high-density housing, welfare issues, and pathogenic infections. While antibiotics have commonly been used to treat many of these issues, they are being removed from poultry production globally due to increased microbial resistance. Precision glycans offer a viable alternative to antibiotics by modulating microbial metabolic pathways. In this study, we investigated the effects of precision glycan supplementation on productivity and gut microbiota in broilers. The experiment was conducted in a commercial setting using 32,400 male Ross chickens randomly divided into three sheds with 10,800 birds each. One shed with 12 pen replicates of 900 birds was used as control, while the other two with an equal number of replicates and birds were assigned to precision glycan supplementation. The treatment significantly improved the average daily weight gain and feed conversion ratio, with a significant modification in the abundance of several bacterial taxa in the caecum, ileum, and ileum mucosa microbial communities. There was increased richness and diversity in the caecum, with a reduction in Proteobacteria and an increase in Firmicutes. Richness remained unchanged in the ileum, with an increase in diversity and reduction in pathogenic genera like Clostridium and Escherichia-Shigella. Ileum mucosa showed a lower abundance of mucin degraders and an increased presence of next-generation probiotics. Supplemented birds showed a high level of disease resistance when the farm experienced an outbreak of infectious bronchitis, evidenced by lower mortality. Histological analysis confirmed improvements in the ileum and liver health, where the precision glycan supplementation reduced the area of congested sinusoids compared to the control group in the liver and significantly improved ileum intestinal morphology by increasing crypt depth and surface area. These results collectively suggest that precision glycans offer substantial benefits in poultry production by improving productivity, gut health, and disease resistance.

Microbiome analysis of bile samples in patients with choledocholithiasis and hepatobiliary disorders.

The involvement of bacteria in the pathogenesis of biliary tract disease is largely unknown. In this study, we investigated the microbiota of the biliary tissue among adult patients with choledocholithiasis during endoscopic retrograde cholangiography (ERCP). 16S rDNA sequencing of bile samples, culture, and data of the medication history, underlying diseases, and liver function tests were used for the interpretation of differences in the composition of detected bacterial taxa. The four most common phyla in the bile samples included Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes. Infection with anaerobic and microaerophilic bacteria showed host specificity, where Fusobacterium, Prevotella, Veillonella, Propionibacterium, Gemella, and Helicobacter coexist in the same patients. Clostridium and Peptoclostridium spp. were detected in 80% and 86% of the patients, where the highest relative abundance rates were detected in patients with elevated alkaline phosphatase (ALP) levels and leukocytosis, respectively. Higher diversity in the bacterial population was detected in patients with common bile duct (CBD) stone, in which the richness of an unclassified member of Alphaproteobacteria plus Helicobacter, Enterobacter/Cronobacter spp., Sphingomonas, Prevotella, Fusobacterium and Aeromonas were detected. Our findings suggested correlations between the presence and relative abundance of several bacterial taxa and CBD stone formation and the effect of medication and underlying diseases on the bile microbial communities. A study on a higher number of bile samples from patients compared with the control group could reveal the role of these bacteria in the pathogenesis of biliary tract disease.

Interactions between Mediterranean Diet Supplemented with Dairy Foods and the Gut Microbiota Influence Cardiovascular Health in an Australian Population.

The impact of a Mediterranean diet on the intestinal microbiome has been linked to its health benefits. We aim to evaluate the effects of a Mediterranean diet supplemented with dairy foods on the gut microbiome in Australians at risk of cardiovascular disease. In a randomised controlled cross-over study, 34 adults with a systolic blood pressure ≥120 mmHg and with risk factors for cardiovascular disease were randomly allocated to a Mediterranean diet with 3-4 daily serves of dairy foods (Australian recommended daily intake (RDI) of 1000-1300 mg per day (MedDairy)) or a low-fat (LFD) control diet. Between each 8-week diet, participants underwent an 8-week washout period. Microbiota characteristics of stool samples collected at the start and end of each diet period were determined by 16S rRNA amplicon sequencing. MedDairy-associated effects on bacterial relative abundance were correlated with clinical, anthropometric, and cognitive outcomes. No change in the overall faecal microbial structure or composition was observed with either diet (p > 0.05). The MedDairy diet was associated with changes in the relative abundance of several bacterial taxa, including an increase in Butyricicoccus and a decrease in Colinsella and Veillonella (p < 0.05). Increases in Butyricicoccus relative abundance over 8 weeks were inversely correlated with lower systolic blood pressure (r = -0.38, p = 0.026) and positively correlated with changes in fasting glucose levels (r = 0.39, p = 0.019), specifically for the MedDairy group. No significant associations were observed between the altered taxa and anthropometric or cognitive measures (p > 0.05). Compared to a low-fat control diet, the MedDairy diet resulted in changes in the abundance of specific gut bacteria, which were associated with clinical outcomes in adults at risk of CVD.

Evaluation of Tannin-Delivery Approaches for Gut Microbiota Modulation: Comparison of Pectin-Based Microcapsules and Unencapsulated Extracts.

The aim of this study was to investigate the impact of tannins on gut microbiota composition and activity, and to evaluate the use of pectin-microencapsulation of tannins as a potential mode of tannin delivery. Thus, pectin-tannin microcapsules and unencapsulated tannin extracts were in vitro digested and fermented, and polyphenol content, antioxidant capacity, microbiota modulation, and short-chain fatty acid (SCFA) production were analyzed. Pectin microcapsules were not able to release their tannin content, keeping it trapped after the digestive process, and are therefore not recommended for tannin delivery. Unencapsulated tannin extracts were found to exert a positive effect on the human gut microbiota. The digestion step resulted to be a fundamental requirement in order to maximize tannin bioactive effects, especially with regard to condensed tannins, as the antioxidant capacity exerted and the SCFAs produced were greater when tannins were submitted to digestion prior to fermentation. Moreover, tannins interacted differently with the intestinal microbiota depending on whether they underwent prior digestion or not. Polyphenol content and antioxidant capacity correlated with SCFA production and with the abundance of several bacterial taxa.

Soil Suppressiveness Against Pythium ultimum and Rhizoctonia solani in Two Land Management Systems and Eleven Soil Health Treatments.

The soil microbiome is known to be crucial for the control of soil-borne plant diseases. However, there is still little knowledge on how to modify the soil microbiome to induce or increase disease suppressiveness. In the present study, we applied eleven soil health treatments combined with conventional and organic agricultural management in a long-term field experiment. Suppressiveness against Pythium ultimum and Rhizoctonia solani was assessed in bioassays for 2 years. In addition, the microbiome community composition and microbial abundance were determined. We found that while several treatments changed the microbial community composition compared to the control, only a combination treatment of anaerobic soil disinfestation, hair meal, and compost addition resulted in suppressiveness against P. ultimum. Pythium suppressiveness is likely to have been caused by an increased microbial abundance and activity. Moreover, the increased abundance of several bacterial taxa, such as Pseudomonas sp., Chryseobacterium sp., members of the family Chitinophagaceae, and the fungal genus Mortierella sp. and family Trichosporonaceae, was measured. There was no overall difference in suppressiveness between conventional and organic land management. Also, no suppressiveness against R. solani could be detected. Our results indicate that a treatment combining the reduction of microorganisms followed by a recovery phase with high amounts of organic amendments may be more effective in inducing suppressiveness than treatments consisting of only one of these measures.

Seasons Influence the Native Gut Microbiome of Lake Trout Salvelinus namaycush

The fish gut microbiome plays an essential role in the host’s development and survival. Environmental factors can shape the gut microbiome and potentially mediate physiological performance. Seasonal environments that experience regular abiotic and biotic transitions likely drive variability in the gut microbiome. However, we know very little about how seasonal transitions interact with the gut microbiome, especially at northern latitudes where seasonality is exaggerated. Therefore, in this study, we analyzed the native gut microbiome of a flexible top predator fish species, the lake trout, across seasons in a boreal lake using 16S rRNA sequencing. Seasonal changes explained one third of the bacterial variance. The relative abundance of several bacterial taxa influenced the observed seasonal differences in the community; pathogenic Pseudomonas and Stenotrophomonas were most abundant in the spring and winter seasons, and chemoheterotrophic Macrococcus and Lelliottia were most abundant in the summer. The fall season was dominated by unclassified Clostridiaceae, potentially linked to a shift in lake trout foraging. Therefore, we present novel evidence that suggests seasonality is likely to shape the native gut microbiome of lake trout; however, the mechanistic links between the environment and the microbial diversity of the gut remain to be uncovered.

The Potential Impact of Age on Gut Microbiota in Patients with Major Depressive Disorder: A Secondary Analysis of the Prospective Observational Study.

We aimed to investigate the impact of aging on the relationship among the composition of gut microbiota, gastrointestinal (GI) symptoms, and the course of treatment for major depressive disorder (MDD) by analyzing the datasets from our previous study. Patients with MDD were recruited, and their stools were collected at three time points (baseline, midterm, and endpoint) following the usual antidepressant treatment. Gut microbiota were analyzed using 16S rRNA gene sequencing. Patients were categorized into two groups based on their age: the late-life group over 60 years and the middle-aged group under 60 years. GI symptoms were assessed with scores of item 11 of the Hamilton Anxiety Rating Scale. One hundred and ninety samples were collected from 32 patients with MDD. Several gut microbes had higher relative abundances in the late-life group than in the middle-aged group. In addition, the late-life group showed significantly higher diversity in the Chao1 index at baseline compared with the middle-aged group. We further found possible microbial taxa related to GI symptoms in patients with late-life depression. The abundance of several bacterial taxa may contribute to GI symptoms in the late-life depression, and our findings suggest that the therapeutic targets for the application of gut microbiota may differ depending on the age group of patients with depression.

RF10 | PMON241 Temporal Changes in Phenotype and Gut microbiota in PCOS Mouse Model Induced by Prenatal Androgen Exposure.

Abstract PCOS is a complex multigenic disorder with strong epigenetic and environmental influence. Previous reports have suggested that fetal over-exposure to androgens contributes to the development of PCOS after birth. On the other hands, recent studies on both human and rodent models of PCOS have demonstrated the relationship between PCOS and gut microbiome in adulthood. Furthermore, gut microbiome in obese adolescent with PCOS are different from obese adolescent without PCOS. However, the mechanism has not been revealed and it is unclear which events appear first, PCOS phenotypes or gut microbiome. We wondered if prenatal androgen exposure leads gut microbial dysbiosis early in life and is associated with the development of PCOS in later life. To test this hypothesis, we examined the temporal changes in the phenotypes of PCOS and gut microbiome using prenatally androgenized (PNA) model mice, an well-established model of PCOS. PNA model was generated by subcutaneously injecting pregnant dams with dehydroepiandrosterone (DHT) on days 16, 17, and 18 of gestation. Phenotypes and gut microbiome activity were compared between PCOS model mice (n=12/group) and control mice (n=10/group) at each developmental stage of 4 weeks (prepuberty), 6 weeks (puberty), 8 weeks (adolescent), 12 weeks (young adulthood), and 16 weeks (adulthood), respectively. The determinants for PCOS development are onset of puberty, estrous cycle, morphology of ovaries, serum testosterone levels, body weight, the size of parametrial adipocytes, and insulin resistance. For evaluation of gut microbiome, next generation sequencing and bioinformatics analysis of 16S rRNA genes were performed on obtained DNA from mouse fecal samples. PNA groups resulted in delayed puberty onset, disrupted estrous cycle, and increased testosterone levels from 6 weeks. Increased atretic antral follicles were observed in PNA groups at 6, 12, and 16 weeks. Additionally, PNA groups showed increased body weight, hypertrophy of parametrial adipocytes, and insulin resistant from 12 weeks. As for gut microbiome, PNA exhibited altered alpha-diversity from 8 weeks and beta-diversity at 8 weeks. Composition of gut microbiome was already altered from 4 weeks. At phylum level, Firmicutes phylum are significantly increased in PNA groups at 4 and 8, and decreased at 16 weeks. Actinobacteria phylum showed significant decrease at 6 and 8 weeks in PNA groups. At genus level, relative abundance of several bacterial taxa differed significantly between control and PNA groups; Allobaculum, Adlercreutzia which produce equol, Roseburia which produce butyric acid, and Sutterella were significantly decreased in PNA groups at multiple stages of development. In conclusion, our findings suggest that the alteration of gut microbiome appears simultaneously or even earlier than the presence of PCOS phenotypes, and that normalizing microbiome could improve pathologic condition of PCOS. In addition, early intervention of gut microbiome might indicate preventive care for women at high-risk of developing PCOS. Presentation: Saturday, June 11, 2022 1:18 p.m. - 1:23 p.m., Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

Changes to the Gut Microbiome in Young Children Showing Early Behavioral Signs of Autism.

The human gut microbiome has increasingly been associated with autism spectrum disorder (ASD), which is a neurological developmental disorder, characterized by impairments to social interaction. The ability of the gut microbiota to signal across the gut-brain-microbiota axis with metabolites, including short-chain fatty acids, impacts brain health and has been identified to play a role in the gastrointestinal and developmental symptoms affecting autistic children. The fecal microbiome of older children with ASD has repeatedly shown particular shifts in the bacterial and fungal microbial community, which are significantly different from age-matched neurotypical controls, but it is still unclear whether these characteristic shifts are detectable before diagnosis. Early microbial colonization patterns can have long-lasting effects on human health, and pre-emptive intervention may be an important mediator to more severe autism. In this study, we characterized both the microbiome and short-chain fatty acid concentrations of fecal samples from young children between 21 and 40 months who were showing early behavioral signs of ASD. The fungal richness and acetic acid concentrations were observed to be higher with increasing autism severity, and the abundance of several bacterial taxa also changed due to the severity of ASD. Bacterial diversity and SCFA concentrations were also associated with stool form, and some bacterial families were found with differential abundance according to stool firmness. An exploratory analysis of the microbiome associated with pre-emptive treatment also showed significant differences at multiple taxonomic levels. These differences may impact the microbial signaling across the gut-brain-microbiota axis and the neurological development of the children.

Transplantation of bacteriophages from ulcerative colitis patients shifts the gut bacteriome and exacerbates the severity of DSS colitis

BackgroundInflammatory bowel diseases (IBDs) including Crohn’s disease (CD) and ulcerative colitis (UC) are characterized by chronic and debilitating gut inflammation. Altered bacterial communities of the intestine are strongly associated with IBD initiation and progression. The gut virome, which is primarily composed of bacterial viruses (bacteriophages, phages), is thought to be an important factor regulating and shaping microbial communities in the gut. While alterations in the gut virome have been observed in IBD patients, the contribution of these viruses to alterations in the bacterial community and heightened inflammatory responses associated with IBD patients remains largely unknown.ResultsHere, we performed in vivo microbial cross-infection experiments to follow the effects of fecal virus-like particles (VLPs) isolated from UC patients and healthy controls on bacterial diversity and severity of experimental colitis in human microbiota-associated (HMA) mice. Shotgun metagenomics confirmed that several phages were transferred to HMA mice, resulting in treatment-specific alterations in the gut virome. VLPs from healthy and UC patients also shifted gut bacterial diversity of these mice, an effect that was amplified during experimental colitis. VLPs isolated from UC patients specifically altered the relative abundance of several bacterial taxa previously implicated in IBD progression. Additionally, UC VLP administration heightened colitis severity in HMA mice, as indicated by shortened colon length and increased pro-inflammatory cytokine production. Importantly, this effect was dependent on intact VLPs.ConclusionsOur findings build on recent literature indicating that phages are dynamic regulators of bacterial communities in the gut and implicate the intestinal virome in modulating intestinal inflammation and disease.EQTzi7uzN3oVQtNZuyDoLGVideo

Metformin modulates microbiota-derived inosine and ameliorates methamphetamine-induced anxiety and depression-like withdrawal symptoms in mice

BackgroundMetformin exhibits therapeutic potential in behavioural deficits induced by methamphetamine (METH) in rats. Emerging studies suggest gut microbiota may impact psychiatric symptoms, but there is no direct evidence supporting metformin’s participation in the pathophysiology of withdrawal symptoms via modulation of gut microbiota. MethodsIn order to define the functional impacts of gut microbiota and metformin to the behavioural deficits during METH withdrawal, we utilized a combination of fecal microbiota transplantation (FMT), high-throughput sequencing, and untargeted metabolomics technologies. ResultsFirst, METH addicts exhibited higher α diversity and distinct microbial structures compared to healthy controls. In particular, the relative abundance of Rikenellaceae was positively correlated with the severity of anxiety and depression. Second, both human-to-mouse and mouse-to-mouse FMTs confirmed that METH-altered-microbiota transplantation is sufficient to promote anxiety and depression-like behaviours in recipient germ-free mice, and these behavioural disturbances could be ameliorated by metformin. In-depth analysis revealed that METH significantly altered the bacterial composition and structure as well as relative abundance of several bacterial taxa and metabolites, including Rikenellaceae and inosine, respectively, whereas add-on metformin could remodel these alterations. Finally, the inosine complementation successfully restored METH-induced anxiety and depression-like behaviours in mice. ConclusionThis study demonstrates that METH withdrawal-induced anxiety and depression-like behaviours are reversible and transmissible via gut microbiota in a mouse model. The therapeutic effects of metformin on psychiatric manifestations are associated with microbiota-derived metabolites, highlighting the role of the gut microbiota in substance use disorders and the pathophysiology of withdrawal symptoms.

Dynamics of Bacterial Communities on Eggshells and on Nest Materials During Incubation in the Oriental Tit (Parus minor).

Eggshell bacterial communities may affect hatching success and nestling's condition. Nest materials are in direct contact with the eggshells, but the relationships with the eggshell microbiome during incubation have not been fully elucidated. Here, we characterize eggshell and nest material bacterial communities and their changes during incubation in the Oriental Tit (Parus minor). Bacterial communities on the nest material were relatively stable and remained distinct from the eggshell communities and had higher diversity and greater phylogenetic clustering than the eggshell communities from the same nest, resulting in lower phylogenetic turnover rate of nest material microbiome during incubation than expected by chance. While the species diversity of both communities did not change during incubation, we found significantly greater changes in the structure of bacterial communities on the eggshell than on the nest material. However, eggshell microbiome remained distinct from nest material microbiome, suggesting independent dynamics of the two microbiomes during incubation. We detected an increase in the relative abundance of several bacterial taxa on the eggshell that likely come from the bird's skin, feathers, cloaca/intestine, or uropygial secretion which suggests some exchange of bacteria between the incubating bird and the eggshell. Furthermore, incubation appeared to promote the abundance of antibiotic producing taxa on the eggshell, which may hypothetically inhibit growth of many bacteria including pathogenic ones. Our results suggest that the future studies should focus on simultaneous monitoring of absolute abundance as well as relative abundance in communities on eggshells, nest materials, and the incubating bird's body.

P–632 Examination of temporal changes in phenotype and gut microbiome during the process of growth in polycystic ovary syndrome (PCOS) model induced by prenatal androgen exposure

Abstract Study question From when do abnormality in gut microbiome and phenotypes of PCOS appear during the process of growth? Summary answer Reproductive phenotypes of PCOS appear from 6 weeks and metabolic phenotypes from 12 weeks onward. Alteration in gut microbiome appears as early as 4 weeks. What is known already The etiology of PCOS remains largely unknown, however PCOS is considered as a complex multigenic disorder with strong epigenetic and environmental influence. Previous studies have suggested that fetal over-exposure to androgens could be the main factor of the development of PCOS after birth. On the other hands, recent studies on both human and PCOS rodent models have demonstrated the association between PCOS and alteration of gut microbiome in adulthood. Furthermore, it was recently reported that gut microbiome in obese adolescent with PCOS is different from obese adolescent without PCOS. Study design, size, duration A rodent PCOS model induced by prenatal dehydroepiandrosterone (DHT) exposure was applied to this study. Phenotypes and gut microbiome were compared between PCOS model mice (n = 12/group) and control mice (n = 10/group) at each stage of growth; 4 weeks (prepuberty), 6 weeks (puberty), 8 weeks (adolescent), 12 weeks (young adult), and 16 weeks (adult). The determinants for PCOS phenotypes are onset of puberty, estrous cycle, morphology of ovaries, serum testosterone level, body weight, and insulin resistance. Participants/materials, setting, methods Pregnant dams were subcutaneously injected on days of 16, 17, and 18 of gestation with either sesame oil for control groups or sesame oil containing 250µg of DHT for prenatal DHT groups. The evaluation of PCOS phenotypes and gut microbiome in female offspring were performed at each stage of growth. For examination of gut microbiota, next generation sequencing and bioinformatics analysis of 16S rRNA genes were performed on DNA extracted from mouse fecal samples. Main results and the role of chance Prenatal DHT mice exhibited delayed puberty onset, disrupted estrous cycle, and significantly increased testosterone levels from 6 weeks onward. Significantly increased atretic antral follicles were observed in prenatal DHT mice at 6, 12, and 16 weeks. Prenatal DHT mice showed significantly decreased body weight at 4, 6, 8 weeks and increased body weight from 12 weeks onward. As for gut microbiome, alpha-diversity was significantly different between control and prenatal DHT mice from 8 weeks onward and beta-diversity was significantly different at 6 and 8 weeks. Altered composition of gut microbiota was observed as early as 4 weeks. At phylum level, Firmicutes are significantly increased in prenatal DHT mice at 4 and 8 weeks and decreased at 16 weeks. Actinobacteria phylum showed significant decrease at 6 and 8 weeks in prenatal DHT mice. At genus level, relative abundance of several bacterial taxa significantly differed between control and prenatal DHT mice; some taxa, such as Allobaculum, Adlercreutzia, Bilophila, Clostridium, Gemella, Gemmiger, Roseburia, Ruminococcus, Staphylococcus, and Sutterella, exhibited constant increase or decrease in prenatal DHT mice during the process of growth. Interestingly, Roseburia was never detected in prenatal DHT mice, while approximately half of control mice harbored Roseburia at 12 and 16 weeks. Limitations, reasons for caution It is not clearly determined whether alteration in gut microbiome is cause or result of PCOS development, although the changes in gut microbiome seemed to precede the appearance of typical PCOS phenotypes in the present study. Mouse model does not completely recapitulate human PCOS. Wider implications of the findings: Our findings suggest that prenatal androgen exposure causes alteration of gut microbiome from pre-puberty onward, even before PCOS phenotypes become apparent. Intervention for girls at risk of PCOS with pre/pro-biotics may prevent them from developing PCOS in future. Trial registration number Not applicable

Intrauterine antibiotic exposure affected neonatal gut bacteria and infant growth speed

Although abundant evidence has suggested that early-life antibiotic exposure was associated with adipogenesis later in life, limited data were available on the effect of intrauterine antibiotic exposure on infant growth and growth speed. Additionally, few studies have investigated the role of the neonatal gut microbiota in the above association. In this study, we examined the association between intrauterine cumulative antibiotic exposure and infant growth and explored the potential role of the neonatal gut microbiota in the association. 295 mother-child pairs from the Shanghai Maternal-Child Pairs Cohort (MCPC) study were included, and meconium samples and infant growth measurements were assessed. Z-scores of length-for-age, weight-for-age (weight-for-age), and body mass index (BMI)-for-age (BMI-for-age) were calculated. Eighteen common antibiotics were measured in meconium. Multivariable linear regression models were applied to test the interrelationships between antibiotic exposure, diversity indicators, and the relative abundance of selected bacterial taxa from phylum to genus levels from least absolute shrinkage and selection operator (LASSO) and infant growth indicators. The detection rates of the 18 antibiotics, except for chlortetracycline, penicillin, and chloramphenicol, were below 10 %. Penicillin was found to be positively associated with infant growth at birth and with growth speed from 2 to 6 months. The Pielou and Simpson indexes were negatively associated with meconium penicillin. Nominally significant associations between penicillin and the relative abundances of several bacterial taxa from the phyla Proteobacteria, Bacteroidetes, and Firmicutes were found. The Pielou and Simpson indexes were also found to be negatively associated with infant growth. Among taxa selected from LASSO regression, the relative abundances of the phyla Actinobacteria and Firmicutes and order Bifidobacteriales were found to be significantly associated with weight and BMI growth speeds from 2 to 6 months. In conclusion, intrauterine antibiotic exposure can affect infant growth. The neonatal gut microbiota might play a role in the abovementioned association.

Gut microbiota signature in treatment-na\xefve attention-deficit/hyperactivity disorder

Compelling evidence supports alterations in gut microbial diversity, bacterial composition, and/or relative abundance of several bacterial taxa in attention-deficit/hyperactivity disorder (ADHD). However, findings for ADHD are inconsistent among studies, and specific gut microbiome signatures for the disorder remain unknown. Given that previous studies have mainly focused on the pediatric form of the disorder and involved small sample sizes, we conducted the largest study to date to compare the gastrointestinal microbiome composition in 100 medication-naïve adults with ADHD and 100 sex-matched healthy controls. We found evidence that ADHD subjects have differences in the relative abundance of several microbial taxa. At the family level, our data support a lower relative abundance of Gracilibacteraceae and higher levels of Selenomonadaceae and Veillonellaceae in adults with ADHD. In addition, the ADHD group showed higher levels of Dialister and Megamonas and lower abundance of Anaerotaenia and Gracilibacter at the genus level. All four selected genera explained 15% of the variance of ADHD, and this microbial signature achieved an overall sensitivity of 74% and a specificity of 71% for distinguishing between ADHD patients and healthy controls. We also tested whether the selected genera correlate with age, body mass index (BMI), or scores of the ADHD rating scale but found no evidence of correlation between genera relative abundance and any of the selected traits. These results are in line with recent studies supporting gut microbiome alterations in neurodevelopment disorders, but further studies are needed to elucidate the role of the gut microbiota on the ADHD across the lifespan and its contribution to the persistence of the disorder from childhood to adulthood.

Compositional Differences in the Oral Microbiome of E-cigarette Users.

Electronic (e)-cigarettes have been advocated as a safer alternative to conventional tobacco cigarettes. However, there is a paucity of data regarding the impact of e-cigarette aerosol deposition on the human oral microbiome, a key component in human health and disease. We aimed to fill this knowledge gap through a comparative analysis of the microbial community profiles from e-cigarette users and healthy controls [non-smokers/non-vapers (NSNV)]. Moreover, we sought to determine whether e-cigarette aerosol exposure from vaping induces persistent changes in the oral microbiome. To accomplish this, salivary and buccal mucosa samples were collected from e-cigarette users and NSNV controls, with additional oral samples collected from e-cigarette users after 2 weeks of decreased use. Total DNA was extracted from all samples and subjected to PCR amplification and sequencing of the V3-V4 hypervariable regions of the 16S rRNA gene. Our analysis revealed several prominent differences associated with vaping, specific to the sample type (i.e., saliva and buccal). In the saliva, e-cigarette users had a significantly higher alpha diversity, observed operational taxonomic units (OTUs) and Faith’s phylogenetic diversity (PD) compared to NSNV controls, which declined with decreased vaping. The buccal mucosa swab samples were marked by a significant shift in beta diversity between e-cigarette users and NSNV controls. There were also significant differences in the relative abundance of several bacterial taxa, with a significant increase in Veillonella and Haemophilus in e-cigarette users. In addition, nasal swabs demonstrated a trend toward higher colonization rates with Staphylococcus aureus in e-cigarette users relative to controls (19 vs. 7.1%; p = n.s.). Overall, these data reveal several notable differences in the oral bacterial community composition and diversity in e-cigarette users as compared to NSNV controls.

Combined hormonal contraceptives are associated with minor changes in composition and diversity in gut microbiota of healthy women

Recent human and animal studies have found associations between gut microbiota composition and serum levels of sex hormones, indicating that they could be an important factor in shaping the microbiota. However, little is known about the effect of regular hormonal fluctuations over the menstrual cycle or CHC-related changes of hormone levels on gut microbiota structure, diversity and dynamics. The aim of this study was to investigate the effect of CHCs on human gut microbiota composition. The effect of CHC pill intake on gut microbiota composition was studied in a group of 7 healthy pre-menopausal women using the CHC pill, compared to the control group of 9 age-matched healthy women that have not used hormonal contraceptives in the six months prior the start of the study. By analyzing the gut microbiota composition in both groups during one menstrual cycle, we found that CHC usage is associated with a minor decrease in gut microbiota diversity and differences in the abundance of several bacterial taxa. These results call for further investigation of the mechanisms underlying hormonal and hormonal contraceptive-related changes of the gut microbiota and the potential implications of these changes for women's health. This article is protected by copyright. All rights reserved.

Experimental infection with the hookworm, Necator americanus, is associated with stable gut microbial diversity in human volunteers with relapsing multiple sclerosis

BackgroundHelminth-associated changes in gut microbiota composition have been hypothesised to contribute to the immune-suppressive properties of parasitic worms. Multiple sclerosis is an immune-mediated autoimmune disease of the central nervous system whose pathophysiology has been linked to imbalances in gut microbial communities.ResultsIn the present study, we investigated, for the first time, qualitative and quantitative changes in the faecal bacterial composition of human volunteers with remitting multiple sclerosis (RMS) prior to and following experimental infection with the human hookworm, Necator americanus (N+), and following anthelmintic treatment, and compared the findings with data obtained from a cohort of RMS patients subjected to placebo treatment (PBO). Bacterial 16S rRNA high-throughput sequencing data revealed significantly decreased alpha diversity in the faecal microbiota of PBO compared to N+ subjects over the course of the trial; additionally, we observed significant differences in the abundances of several bacterial taxa with putative immune-modulatory functions between study cohorts. Parabacteroides were significantly expanded in the faecal microbiota of N+ individuals for which no clinical and/or radiological relapses were recorded at the end of the trial.ConclusionsOverall, our data lend support to the hypothesis of a contributory role of parasite-associated alterations in gut microbial composition to the immune-modulatory properties of hookworm parasites.

Description of the fecal microbiota of siblings from Costa Rica with and without affective and psychotic disorders

• Individuals affected of serious mental disorders have significantly increased LPS producing Pseudomonas and reduced butyrate producing Ruminococcaceae . • Bacterial taxa associated with healthy phenotype, such as B arnesiella and Rumicococcaceae were depleted in individuals affected with psychosis. • Significant alternations were found in the pathways associated with amino acid metabolism in affected individuals in comparison to the unaffected. The pathogenesis of mental disorders remains poorly understood and there are enormous challenges in the development of biomarkers and more effective therapeutic options. A total of 13 pairs of 26 siblings discordant for mental disorders, affected and unaffected, were subjected to Best Estimate Diagnosis process and clinical assessments with respect to their diagnosis, current mental health status and disability, resilience, medication, lifestyle and diet. All participants were of Hispanic ethnicity and residents of the San José Greater Metropolitan Area. Many of the pairs of siblings shared households. Affected individuals displayed major depression, bipolar affective disorder, psychosis non-otherwise specified or schizoaffective disorder. In a subsequent analysis the affected individuals were further divided according to whether they exhibited psychotic features or not. Fecal samples were collected for the analysis of the gut microbiota using 16S rRNA gene amplicon sequencing and imputed metagenomics that were compared within the sibling pairs. Based on beta-diversity analysis, the use of levothyroxine and irbesartan was identified and thus used as confounders. Decreased bacterial richness was observed among the affected participants. The relative abundances of several bacterial taxa showed significant differences, including families Peptostreptococcaceae, Ruminococcaceae, Porphyromonadaceae , and genera Pseudomonas, Barnesiella, Odoribacter, Paludibacter, Lactococcus, Clostridium, Acidaminococcus and Haemophilus. The proportion of Proteobacteria ( Pseudomonas ) was significantly increased in the affected individuals, while the bacterial taxa associated to healthy phenotype, such as Barnesiella and Ruminococcaceae, were depleted in individuals affected with psychosis in comparison to those without psychosis. Based on prediction functions of the gut microbiota, significant alternations were found in the pathways associated with amino acid metabolism in affected individuals in comparison to the unaffected. Our findings suggest the changes in gut microbiota composition and functionality are associated with mental health, its diagnostics, and therapeutics.

Gut microbiota markers associated with obesity and overweight in Italian adults

In the present study, we characterized the distinctive signatures of the gut microbiota (GM) from overweight/obese patients (OB), and normal-weight controls (NW), both of Sardinian origin. Fecal bacterial composition of 46 OB patients (BMI = 36.6 ± 6.0; F/M = 40/6) was analyzed and compared to that of 46 NW subjects (BMI = 21.6 ± 2.1; F/M = 41/5), matched for sex, age and smoking status, by using 16S rRNA gene sequencing on MiSeq Illumina platform. The gut microbial community of OB patients exhibited a significant decrease in the relative abundance of several Bacteroidetes taxa (i.e. Flavobacteriaceae, Porphyromonadaceae, Sphingobacteriaceae, Flavobacterium, Rikenella spp., Pedobacter spp., Parabacteroides spp., Bacteroides spp.) when compared to NW; instead, several Firmicutes taxa were significantly increased in the same subjects (Lachnospiraceae, Gemellaceae, Paenibacillaceae, Streptococcaceae, Thermicanaceae, Gemella, Mitsuokella, Streptococcus, Acidaminococcus spp., Eubacterium spp., Ruminococcus spp., Megamonas spp., Streptococcus, Thermicanus, Megasphaera spp. and Veillonella spp.). Correlation analysis indicated that body fatness and waist circumference negatively correlated with Bacteroidetes taxa, while Firmicutes taxa positively correlated with body fat and negatively with muscle mass and/or physical activity level. Furthermore, the relative abundance of several bacterial taxa belonging to Enterobacteriaceae family, known to exhibit endotoxic activity, was increased in the OB group compared to NW. The results extend our knowledge on the GM profiles in Italian OB, identifying novel taxa linking obesity and intestine.