Microbiota In Samples Research Articles

381. Transplantation of Maternal Intestinal Flora to the Newborn After Elective Cesarean Section - A Randomized Controlled Trial (SECFLOR)

Abstract Background Normal microbial colonization process from the mother to the newborn is disrupted by birth by caesarean section (CS). We assess, whether in CS-delivered infants, the intestinal microbiome could be successfully and safely normalized by postnatal oral transfer of maternal fecal microbiome (FMT). In this double-blinded randomized controlled trial started in autumn 2019, we assess the difference in heterogeneity of the intestinal microbiome between the two groups from birth to 24 months of age. The randomization code was opened in March 2024 when last transplanted child turned one year of age. Primary outcome measures are assessed from samples collected at 3 months of age. Methods 90 healthy pregnant women scheduled for elective CS were recruited. After screening and randomization, within two hours of delivery, 31 newborns were given 3.5 mg of the transplant from their own mothers or placebo mixed in mother’s milk. The children are followed for 24 months. Stool and blood samples from the child and mother are collected during the follow up and analyzed for changes in microbiome heterogeneity between the groups and to assess, for example, immunological changes associated with the transfer. Results All mothers were asymptomatic, no prescribed courses of antibiotics or travelling history outside the European Union region within three months of screening. 38 had positive findings in screening tests. 31 infants were included in the study of whom 15 received the transplant and 16 placebo. 3 adverse events were reported in the transplant group: one infant had thrombocytopenia at the age of two days, which normalized within one week. One infant was diagnosed with bilateral grade one intraventricular hemorrhage at the age of two weeks. One infant was treated for transient tachypnea of the newborn after receiving the transplant. None of the adverse events were considered related to the transplant. Conclusion In our proof-of-concept study we previously demonstrated the effectiveness and safety of our protocol. The immunology and microbiota samples (fecal and blood) of our first-of-a-kind randomized controlled trial are being analyzed and first results will be available in September 2024. Disclosures All Authors: No reported disclosures

Effects of Vegetable and Fruit Juicing on Gut and Oral Microbiome Composition

Background: In recent years, juicing has often been promoted as a convenient way to increase fruit and vegetable intake, with juice-only diets marketed for digestive cleansing and overall health improvement. However, juicing removes most insoluble fiber, which may diminish the health benefits of whole fruits and vegetables. Lower fiber intake can alter the microbiota, affecting metabolism, immunity, and mental health, though little is known about juicing’s specific effects on the microbiota. This study addresses this gap by exploring how juicing impacts gut and oral microbiome composition in an intervention study. Methods: Fourteen participants followed one of three diets—exclusive juice, juice plus food, or plant-based food—for three days. Microbiota samples (stool, saliva, and inner cheek swabs) were collected at baseline, after a pre-intervention elimination diet, immediately after juice intervention, and 14 days after intervention. Moreover, 16S rRNA gene amplicon sequencing was used to analyze microbiota taxonomic composition. Results: The saliva microbiome differed significantly in response to the elimination diet (unweighted UniFrac: F = 1.72, R = 0.06, p < 0.005; weighted UniFrac: F = 7.62, R = 0.23, p-value = 0.0025) with a significant reduction in Firmicutes (p = 0.004) and a significant increase in Proteobacteria (p = 0.005). The juice intervention diets were also associated with changes in the saliva and cheek microbiota, particularly in the relative abundances of pro-inflammatory bacterial families, potentially due to the high sugar and low fiber intake of the juice-related products. Although no significant shifts in overall gut microbiota composition were observed, with either the elimination diet or the juice intervention diets, bacterial taxa associated with gut permeability, inflammation, and cognitive decline increased in relative abundance. Conclusions: These findings suggest that short-term juice consumption may negatively affect the microbiota.

Microbiota in patients with cefuroxime resistance and anal fistula revealed by 16S ribosomal DNA.

Anal fistula is increasingly prevalent due to modern lifestyle factors, and surgery remains the primary treatment. However, the rising incidence of antibiotic resistance, particularly to cefuroxime, complicates perioperative management. The role of gut microbiota in influencing this resistance is not well understood. To investigate the relationship between gut microbiota composition and cefuroxime resistance in anal fistula patients and to assess probiotic intervention impact. This study included 30 anal fistula patients categorized into cefuroxime-sensitive (Cefur-S) and cefuroxime-resistant (Cefur-NS) groups. Gut microbiota samples were collected during colonoscopy, and 16S ribosomal DNA sequencing was performed to analyze microbial diversity. Patients in the Cefur-NS group received a 7-day course of Clostridium butyricum tablets. Post-intervention, microbial composition and cefuroxime resistance were reassessed. Alpha and beta diversity analyses showed no significant differences in microbial diversity between the Cefur-S and Cefur-NS groups. However, effect size analysis identified Roseburia and Butyricicoccus as dominant genera in the Cefur-S group, with higher butyrate production potentially protecting against cefuroxime resistance. Post-intervention, the Cefur-NS group showed a significant reduction in cefuroxime resistance, improved stool consistency, and reduced bowel movement frequency. This study suggests that specific gut microbiota, particularly Butyricicoccus and Roseburia, may mitigate cefuroxime resistance in anal fistula patients by increasing butyrate production. Probiotic intervention targeting gut microbiota composition presents a promising strategy for reducing antibiotic resistance and improving clinical outcomes.

The role of skin microbiota in lichen planus from a Mendelian randomization perspective.

Lichen planus is a chronic skin lesion characterized by pruritic violaceous papules, which has a high risk of morbidity. Skin microbiota plays an important role in the maintenance of cutaneous mucosal barrier and human health and immune homeostasis. Studies have shown that skin microbiota may play a role in the pathogenesis of lichen planus, but it is not yet clear. MR studies have been performed to determine causal associations. Lichen planus samples from Finn database were extracted from published GWAS data, including 6,411 cases and 405,770 controls; skin microbiota samples were gathered from a meta-analysis of German population-based GWAS, which included 1,656 skin samples from two cohorts: KORA FF4 (n = 353) and PopGen (n = 294), comprising 4,685,714 SNPs. The IVW method was used as the main statistical method, supplemented by three methods: MR-Egger, weighted median and weighted mode. FDR correction and MR Steiger test were used to reduce false positives. IVW method revealed a negative correlation between Burkholderia in the moist anterior elbow and lichen planus (OR: 0.934, 95% CI: 0.910-0.986, P = 0.017). These associations remained stable following false discovery rate correction (P < 1e-5). Our study highlights a possible causal role of Burkholderia in the development of lichen planus and suggests that Burkholderia may reduce the occurrence of lichen planus by affecting macrophages.

Maternal pre- and postnatal stress and maternal and infant gut microbiota features.

Maternal stress can have short and long term adverse (mental) health effects for the mother and her child. Previous evidence suggests that the gut microbiota may be a potential mediator and moderator for the effects of stress via various pathways. This study explored the maternal microbiota trajectory during pregnancy as well as the association between pre- and postnatal maternal stress and features of the maternal and infant gut microbiota during and after pregnancy. In line with previous research, we hypothesized that maternal stress would be positively related to maternal and infant microbiota volatility and that infants of highly stressed mothers would show a relative increase in Proteobacteria and a relative decrease in Bifidobacterium. We collected maternal stool samples at 18 and 32 weeks of pregnancy and 8 months postpartum. Infant stools samples were obtained at 2, 6 and 12 weeks and 8 months postpartum. All samples were analyzed using shotgun metagenome sequencing. We also collected several measures of maternal stress (self-reported depression, anxiety, and stress, and hair cortisol and cortisone), most at the same time points as the microbiota samples. Our data indicated that the maternal microbiota does not undergo drastic changes from the second to the third trimester of pregnancy but that the postpartum microbiota differs significantly from the prenatal microbiota. Furthermore, we identified associations between several stress measures and maternal and infant gut microbiota features at different time points including positive and negative associations with alpha diversity, beta diversity and individual microbial phyla and species relative abundances. Also, the maternal stress composite score, the perceived stress score and the log-ratio of hair cortisol and cortisone were all positively associated with infant microbiota volatility. Our study provides evidence that maternal prenatal and postnatal stress is related to both the maternal and the infant microbiota. Collectively, this and previous studies indicate that maternal stress does not uniformly associate with most gut microbial features. Instead, the associations are highly time point specific. Regarding infant microbiota volatility, we have consistently found a positive association between stress and infant microbiota volatility. This warrants future research investigating this link in more depth.

Unraveling Microplastic Effects on Gut Microbiota across Various Animals Using Machine Learning.

Microplastics, rapidly expanding and durable pollutant, have been shown to significantly impact gut microbiota across a spectrum of animal species. However, comprehensive analyses comparing microplastic effects on gut microbiota among these species are still limited, and the critical factors driving these effects remain to be clarified. To address these issues, we compiled 1352 gut microbiota samples from six animal categories, employing machine learning to conduct an in-depth meta-analysis. Our study revealed that mice, compared with other animals, not only exhibit a heightened susceptibility to the toxic effects of microplastics─evidenced by decreased gut microbiota diversity, increased Firmicutes/Bacteroidetes ratios, destabilized microbial networks, and disruption in the equilibrium of beneficial and harmful bacteria─but also possess limited potential to degrade microplastics, unlike earthworms and insects. Furthermore, machine learning models confirmed that exposure duration is the key factor driving changes induced by microplastics in gut microbiota. We also identified Lactobacillus, Helicobacter, and Pseudomonas as potential biomarkers for detecting microplastic toxicity in the animal gut. Overall, these findings provide valuable insights into the health risks and driving factors associated with microplastic exposure across multiple animal species.

Age-stratification reveals age-specific intestinal microbiota signatures in juvenile idiopathic arthritis

ObjectiveJuvenile Idiopathic Arthritis (JIA) comprises diverse chronic inflammatory conditions driven by malfunction of the immune system. The intestinal microbiota is considered a crucial environmental factor correlating with chronic inflammatory diseases, and for JIA certain alterations in the microbiota have already been described.MethodsHere, we have characterized intestinal microbiota samples from 54 JIA patients and 38 pediatric healthy controls by conventional 16S rRNA sequencing and by single-cell analysis for phenotypic features by multi-parameter microbiota flow cytometry (mMFC), which complements the population-based taxonomic profiling with the characterization of individual bacterial cells.ResultsWe found age to be a crucial confounder in microbiota analyses of JIA patients. Age stratification revealed specific microbiota alterations neglected by the general comparison of JIA patients and pediatric controls.ConclusionAge groups presented distinct taxonomic profiles and microbiota phenotypic signatures which transitioned with age, highlighting changes in the microbiota-immune system interaction with age.

Features of the oropharyngeal microbiota of healthy children and those with acute respiratory infections. A prospective single-center randomized study

Background. The oropharyngeal microbiota is involved in the development of colonization resistance, affecting viral adhesion and metabolism. Any deviations in the stability of the environmental microbial niches of the oropharynx alter the local immune response and can trigger severe chronic somatic disorders. Aim. To compare the composition of the microbiota of children during an episode of respiratory infection and healthy volunteers examined in different periods of convalescence. The obtained data can be used to predict the course of the disease, analyze the risk of complications, and assess the frequency of the diseases in the future. Materials and methods. From 20.01.2022 to 23.12.2022, an open-label prospective single-center randomized comparative study was conducted, which included 120 children aged 5-10 who presented with symptoms of acute respiratory infection. The control group consisted of 15 asymptomatic children examined at different periods of convalescence. The study compared changes in the oral microbiota composition of patients and healthy children. The evaluation was performed using complete 16S rRNA gene sequencing on the Oxford Nanopore platform. Taxonometric analysis at the species and genera level was performed using the Knomics-Biota platform. The R programming language was used for statistical processing. In addition, the parameters of α- and β-diversity of the microbiota were assessed. The Chao1 and Shannon indices were calculated to assess α-diversity (diversity within one community). The Chao1 index is based on the number of species found in the sample and also rare species that are found only 1 or 2 times, thus preventing underestimation of diversity. The Shannon index includes both the number of species and their uniformity in the community. A change in the index indicates the dominance of one or more species. The following indicators were used to assess the β-diversity describing the differences between two microbiota samples at the species and genera level: Bray–Curtis dissimilarity (characterizing the ratios of common and different microorganisms between the samples) and the Aitchison distance (reflecting the differences in the proportions of microorganisms). In addition, the balance between the two groups of microorganisms was evaluated using the NearesBalance method, which characterizes the differences between the microbiota of the main and control groups. Results. The results of our study show that during respiratory infection, the state of the oropharyngeal microbiota is characterized by an increase in α-diversity, which is associated with an increase in the proportion of species of Streptococcus salivarius, Streptococcus pneumoniae, Streptococcus pseudopneumoniae, Streptococcus pyogenes, Streptococcus thermophilus and A12 versus the proportion of Streptococcus mitis, Streptococcus oralis, Streptococcus gwangjuense, Streptococcus sanguinis, Streptococcus gordonii and FDAARGOS_192. In the control group, the oropharyngeal microbiota was divided into two clusters. The dominance of streptococci was observed in the first group (control), while the second group had a more uniform representation. Analysis of the changes in microbial communities in the main and control groups can show the stages of oral microbiota recovery after an acute respiratory infection episode. Conclusion. More research is needed in the field of the oropharyngeal microbiome on a larger sample of healthy children, to standardize the communities of the oropharyngeal microbiota, to study the interaction within communities and with the body as a whole. Analysis of the impact of the microbiota on the frequency and course of respiratory infections and the rate of complications opens up new prospects in treating, rehabilitating, and preventing diseases. These research areas can contribute to improving children's health and quality of life and introducing new approaches into clinical practice.

Dysbiosis of the Upper Gastrointestinal Tract in Head-and-Neck Cancer Survivors: A Pilot Study Using the Capsule Sponge Device

Background: A non-endoscopic capsule-sponge device allows sampling the entire length of the esophagus. Here, we compared microbiomes of the oral cavity, esophagus, and gastric corpus collected by oral swab, capsule-sponge device, and endoscopic biopsy, respectively, in patients representing three distinct risk profiles for esophageal squamous cell carcinoma (ESCC). Methods: The study enrolled 11 patients with esophageal squamous intraepithelial neoplasia, 21 patients after curative treatment for head and neck squamous cell cancer (HNSCC) (HNSCC survivors), and 40 patients with functional dyspeptic (FD) symptoms. Microbial genomic DNA was analyzed using 16S rRNA gene amplicon sequencing. Results: The Shannon index of the capsule-sponge sample microbiota was significantly higher in FD group than in patients after treatment for HNSCC, and the Chao index of gastric samples differed between HNSCC survivors and FD patients. Analysis of the β-diversity of FD patients, HNSCC, and esophageal squamous intraepithelial neoplasia showed that different genera formed at each location. The abundance of 205, 116, and 9 genera differed between FD patients and HNSCC survivors in the gastric, capsule-sponge, and oral samples, respectively; 33 genera differed between the FD group and patients with esophageal squamous intraepithelial neoplasia in capsule-sponge samples. Conclusions: The bacterial communities of the upper digestive tract were clustered according to the anatomic site. Despite substantial differences in gastric and esophageal microbiota samples between FD patients and HNSCC survivors, the microbial members and diversity showed small differences between FD patients and those with esophageal squamous intraepithelial neoplasia. It remains unclear whether gastric and esophageal dysbiosis is associated with or is a consequence of treatment for HNSCC.

Development of a High-Resolution Melting Method for the Detection of Clarithromycin-Resistant Helicobacter pylori in the Gastric Microbiome.

Background: The issue of Helicobacter pylori (H. pylori) resistance to clarithromycin (CLR) has consistently posed challenges for clinical treatment. Hence, a rapid susceptibility testing (AST) method urgently needs to be developed. Methods: In the present study, 35 isolates of H. pylori were isolated from 203 gastritis patients of the Guangzhou cohort, and the antimicrobial resistance phenotypes were associated with their genomes to analyze the relevant mutations. Based on these mutations, a rapid detection system utilizing high-resolution melting (HRM) curve analysis was designed and verified by the Shenzhen cohort, which consisted of 38 H. pylori strains. Results: Genomic analysis identified the mutation of the 2143 allele from A to G (A2143G) of 23S rRNA as the most relevant mutation with CLR resistance (p < 0.01). In the HRM system, the wild-type H. pylori showed a melting temperature (Tm) of 79.28 ± 0.01 °C, while the mutant type exhibited a Tm of 79.96 ± 0.01 °C. These differences enabled a rapid distinction between two types of H. pylori (p < 0.01). Verification examinations showed that this system could detect target DNA as low as 0.005 ng/μL in samples without being affected by other gastric microorganisms. The method also showed a good performance in the Shenzhen validation cohort, with 81.58% accuracy, and 100% specificity. Conclusions: We have developed an HRM system that can accurately and quickly detect CLR resistance in H. pylori. This method can be directly used for the detection of gastric microbiota samples and provides a new benchmark for the simple detection of H. pylori resistance.

Characterising and preventing the gut microbiota's inactivation of trifluridine, a colorectal cancer drug

The gut microbiome can metabolise hundreds of drugs, potentially affecting their bioavailability and pharmacological effect. As most gut bacteria reside in the colon, drugs that reach the colon in significant proportions may be most impacted by microbiome metabolism. In this study the anti-colorectal cancer drug trifluridine was used as a model drug for characterising metabolism by the colonic microbiota, identifying correlations between bacterial species and individuals’ rates of microbiome drug inactivation, and developing strategies to prevent drug inactivation following targeted colonic delivery. High performance liquid chromatography and ultra-high performance liquid chromatography coupled with high resolution tandem mass spectrometry demonstrated trifluridine's variable and multi-route metabolism by the faecal microbiota sourced from six healthy humans. Here, four drug metabolites were linked to the microbiome for the first time. Metagenomic sequencing of the human microbiota samples revealed their composition, which facilitated prediction of individual donors’ microbial trifluridine inactivation. Notably, the abundance of Clostridium perfringens strongly correlated with the extent of trifluridine inactivation by microbiota samples after 2 hours (R2 = 0.8966). Finally, several strategies were trialled for the prevention of microbial trifluridine metabolism. It was shown that uridine, a safe and well-tolerated molecule, significantly reduced the microbiota's metabolism of trifluridine by acting as a competitive enzyme inhibitor. Further, uridine was found to provide prebiotic effects. The findings in this study greatly expand knowledge on trifluridine's interactions with the gut microbiome and provide valuable insights for investigating the microbiome metabolism of other drugs. The results demonstrate how protection strategies could enhance the colonic stability of microbiome-sensitive drugs.

Influence of microbiota on the growth and gene expression of Clostridioides difficile in an in vitro coculture model.

Clostridioides difficile is an anaerobic, spore-forming, Gram-positive pathogenic bacterium. This study aimed to analyze the effect of two samples of healthy fecal microbiota on C. difficile gene expression and growth using an in vitro coculture model. The inner compartment was cocultured with spores of the C. difficile polymerase chain reaction (PCR)-ribotype 078, while the outer compartment contained fecal samples from donors to mimic the microbiota (FD1 and FD2). A fecal-free plate served as a control (CT). RNA-Seq and quantitative PCR confirmation were performed on the inner compartment sample. Similarities in gene expression were observed in the presence of the microbiota. After 12 h, the expression of genes associated with germination, sporulation, toxin production, and growth was downregulated in the presence of the microbiota. At 24 h, in an iron-deficient environment, C. difficile activated several genes to counteract iron deficiency. The expression of genes associated with germination and sporulation was upregulated at 24 h compared with 12 h in the presence of microbiota from donor 1 (FD1). This study confirmed previous findings that C. difficile can use ethanolamine as a primary nutrient source. To further investigate this interaction, future studies will use a simplified coculture model with an artificial bacterial consortium instead of fecal samples.

Identification of a higher C-S lyase activity of Staphylococcus hominis in volunteers with unpleasant axillary odour.

Excessive and unpleasant odours that emanate from the skin can induce bromhidrosis and substantially impair a person's quality of life. Enzymatic pathways generating unpleasant odours are well detailed, and among them, the C-S lyase is one of the enzymes involved in the conversion of non-volatile precursors into thiol-type malodorous volatile molecules such as 3M3SH. This study aimed to investigate the variation of axillary odour intensity correlated with Staphylococcus (S.) hominis C-S lyase activity within a group of volunteers after a physical activity. First, a group of 24 volunteers from the same ethnicity with standardized hygienic and alimentary practices participated in a supervised indoor cycling activity. Following this session, worn T-shirts were recovered to enable the olfactory evaluation of axillary odours by qualified experts. To go further, the microbiota from the axillary zone of each volunteer was sampled and the bacterial relative abundance was investigated by using 16S rRNA metasequencing. Then, S. hominis isolates were obtained by culturomics from these microbiota samples and the C-S lyase activity was measured by spectrofluorometry in protein crude extracts. The evaluation of the odour intensity revealed that within the panel, two groups were significantly distinct. A non-odorous group and a malodorous one with volunteers having unpleasant odours. The 16S rRNA metasequencing reveals differences in bacterial communities between the two groups with a significant increase in the relative abundance of S. hominis in the malodorous group compared with the non-odorous one. The C-S lyase activities measured on S. hominis sampled on volunteers from the two groups demonstrate that for an equivalent quantity of protein, this enzymatic activity is significantly higher for the samples originating from the malodorous group. Hence, this study demonstrates that beyond the increase of S. hominis relative abundance, the C-S lyase enzymatic activity of this bacteria is also higher in volunteers with unpleasant axillary odours.

Transfer and persistence of microbiota markers from the human hand to the knife: A preliminary study

New scientific techniques and methods are always needed to link the perpetrators to the incident or the crime scene. Recent microbiota studies based on NGS (Next-generation sequencing) show that various biological samples from crime scenes have the potential to be used in forensic investigations. Especially when DNA traces belonging to more than one person are insufficient to fully determine the genetic profile, a secret sample, such as a microbiota sample created by the suspect's touch, can be used. In this preliminary study, a fictionalized experimental model was designed to investigate the transfer and persistence of the hand microbiome on the knife handle, which has a high potential to be used in criminal incidents, by metagenomic analysis methods. In addition, it was aimed to determine the transfer of specific bacterial species identified only to the person among the five participants onto the knife handle and their persistence over time. In the first stage of the research, samples were collected from the hands of 5 volunteer participants using the swap method, including their palms. Then, after each participant held a different knife, samples were collected from the knife handles via swabs from different angles of the knives at 4 and 24 h and analyzed by metagenomic methods. The findings of this preliminary study showed that the heatmap graphs generated after UniFrac distance analysis were not successful in establishing any similarity between the hand samples and the post-transfer knife handle samples. Nonetheless, it was observed that the transfer of bacterial species detected in the hand samples to knives differed according to the individuals and some bacterial species were transferred to the knife samples held by the participants. The number of bacterial species detected that are specific to each participant's hand sample was 302 in total, and it was determined that a total of 8.28 % of these bacterial species were transferred to the knife handle samples of the 4th hour and 6.95 % to the knife samples of the 24th hour. In the presented study, considering the transfer of some bacterial species in the hand microbiome, which are effective in the variation between individuals, onto the knife; It has been evaluated that some rare bacterial species can be important potential markers to associate the object with the perpetrator.

Protocol for a clinically annotated biorepository of samples from Australian immune-compromised patients to investigate the host–microbiome interaction

IntroductionThe human gut microbiota has the potential to modulate the outcomes of several human diseases. This effect is likely to be mediated through interaction with the host immune system. This...

Clinical Applicability of Microbiota Sampling in a Subfertile Population: Urine versus Vagina.

The urogenital microbiota is increasingly gaining recognition as a significant contributor to reproductive health. Recent studies suggest that microbiota can serve as predictors for fertility treatment outcomes. Our objective was to investigate the degree of similarity in microbial composition between patient-collected urine and vaginal samples in a subfertile population. We enrolled women of reproductive age (20-44 years) diagnosed with subfertility and requiring in vitro fertilization (IVF) or IVF with intracytoplasmic sperm injection (IVF-ICSI) treatment. They self-collected both mid-stream urine samples and vaginal swabs before commencing the IVF or IVF-ICSI procedure. All samples were analysed using the intergenic spacer profiling (IS-pro) technique, a rapid clinical microbiota analysis tool. The main outcome measures were the degree of similarity of microbial composition between the two different, but simultaneously collected, samples. Our findings revealed a high correlation (R squared of 0.78) in microbiota profiles between paired urine and vaginal samples from individual patients. Nevertheless, the urinary microbiota profiles contained fewer species compared to the vaginal microbiota, resulting in minor but distinguishable differences. Furthermore, different subfertility diagnoses appeared to be associated with differences in microbial profiles. A noteworthy observation was the exclusive presence of Escherichia coli (E. coli) in both samples of women diagnosed with male factor subfertility. In conclusion, since urinary microbiota profiles seem to represent a diluted version of the vaginal microbiota, vaginal microbiome sampling to predict fertility treatment outcome seems preferable. To enhance the success of fertility treatments, further research is needed to gain deeper insights into a putative causal role of microbiota in the mechanisms of subfertility.

Microbiota diversity and anti-Pseudogymnoascus destructans bacteria isolated from Myotis pilosus skin during late hibernation.

Symbiotic microorganisms that reside on the host skin serve as the primary defense against pathogens in vertebrates. Specifically, the skin microbiome of bats may play a crucial role in providing resistance against Pseudogymnoascus destructans (Pd), the pathogen causing white-nose syndrome. However, the epidermis symbiotic microbiome and its specific role in resisting Pd in highly resistant bats in Asia are still not well understood. In this study, we collected and characterized skin microbiota samples of 19 Myotis pilosus in China and explored the differences between Pd-positive and negative individuals. We identified inhibitory effects of these bacteria through cultivation methods. Our results revealed that the Simpson diversity index of the skin microbiota for positive individuals was significantly lower than that of negative individuals, and the relative abundance of Pseudomonas was significantly higher in positive bats. Regardless of whether individuals were positive or negative for Pd, the relative abundance of potentially antifungal genera in skin microbiota was high. Moreover, we successfully isolated 165 microbes from bat skin and 41 isolates from positive individuals able to inhibit Pd growth compared to only 12 isolates from negative individuals. A total of 10 genera of Pd-inhibiting bacteria were screened, among which the genera Algoriella, Glutamicibacter, and Psychrobacter were newly discovered as Pd-inhibiting genera. These Pd-inhibiting bacteria metabolized a variety of volatile compounds, including dimethyl trisulfide, dimethyl disulfide, propylene sulfide, 2-undecanone, and 2-nonanone, which were able to completely inhibit Pd growth at low concentrations.IMPORTANCERecently, white-nose syndrome has caused the deaths of millions of hibernating bats, even threatening some with regional extinction. Bats in China with high resistance to Pseudogymnoascus destructans can provide a powerful reference for studying the management of white-nose syndrome and understanding the bats against the pathogen's intrinsic mechanisms. This study sheds light on the crucial role of host symbiotic skin microorganisms in resistance to pathogenic fungi and highlights the potential for harnessing natural defense mechanisms for the prevention and treatment of white-nose syndrome. In addition, this may also provide promising candidates for the development of bioinsecticides and fungicides that offer new avenues for addressing fungal diseases in wildlife and agricultural environments.

Comparison of the full-length sequence and sub-regions of 16S rRNA gene for skin microbiome profiling.

The skin microbiome plays a pivotal role in human health by providing protective and functional benefits. Furthermore, its inherent stability and individual specificity present novel forensic applications. These aspects have sparked considerable research enthusiasm among scholars across various fields. However, the selection of specific 16S rRNA hypervariable regions for skin microbiome studies is not standardized and should be validated through extensive research tailored to different research objectives and targeted bacterial taxa. Notably, third-generation sequencing (TGS) technology leverages the full discriminatory power of the 16S gene and enables more detailed and accurate microbial community analyses. Here, we conducted full-length 16S sequencing of 141 skin microbiota samples from multiple human anatomical sites using the PacBio platform. Based on this data, we generated derived 16S sub-region data through an in silico experiment. Comparisons between the 16S full-length and the derived variable region data revealed that the former can provide superior taxonomic resolution. However, even with full 16S gene sequencing, limitations arise in achieving 100% taxonomic resolution at the species level for skin samples. Additionally, the capability to resolve high-abundance bacteria (TOP30) at the genus level remains generally consistent across different 16S variable regions. Furthermore, the V1-V3 region offers a resolution comparable with that of full-length 16S sequences, in comparison to other hypervariable regions studied. In summary, while acknowledging the benefits of full-length 16S gene analysis, we propose the targeting of specific sub-regions as a practical choice for skin microbial research, especially when balancing the accuracy of taxonomic classification with limited sequencing resources, such as the availability of only short-read sequencing or insufficient DNA.IMPORTANCESkin acts as the primary barrier to human health. Considering the different microenvironments, microbial research should be conducted separately for different skin regions. Third-generation sequencing (TGS) technology can make full use of the discriminatory power of the full-length 16S gene. However, 16S sub-regions are widely used, particularly when faced with limited sequencing resources including the availability of only short-read sequencing and insufficient DNA. Comparing the 16S full-length and the derived variable region data from five different human skin sites, we confirmed the superiority of the V1-V3 region in skin microbiota analysis. We propose the targeting of specific sub-regions as a practical choice for microbial research.

Initial timing of alfalfa hay supplementation manipulates blood parameters, rumen gene expression, and epithelial microbiota in pre-weaning lambs.

The present study aimed to investigate the impact of initiating alfalfa supplementation at either 14 or 42 days of age on growth performance, blood parameters, rumen tissue gene expression, and epithelial microbiota in pre-weaning lambs. A total of 42 seven-day-old male Hu lambs (3.88 ± 0.92kg) were selected for this study. After 7 d of adjustment period, six lambs were slaughtered at 14 d of age to establish a baseline control. The remaining 36 lambs were randomly allocated to two treatment groups, every three lambs were considered a unit, including fed milk replacer, starter pellets, and either alfalfa hay fed at 14 (EAF) or 42 d of age (LAF). Body weight and feed intake were recorded for lamb until 70 d of age. Blood samples, rumen tissue samples, and epithelial microbiota samples were collected from the lambs at 42, 56, and 70 d of age. The results indicated that average daily gain, starter intake, and total dry matter intake were greater in the EAF group compared to the LAF group from 14 to 42 d of age (P < 0.01), but no significant differences from 43 to 70 d of age or during the entire trial. Treatment and age interactively affected the alfalfa intake (P = 0.02) from 43 to 70 d of age. The concentration of serum immunoglobulin A (IgA) (P < 0.01) and the expression of the rumen gene insulin-like growth factor 1 (P < 0.01) were greater in the EAF group compared to the LAF group at 42 d of age. Furthermore, the concentrations of alkaline phosphatase (P = 0.03), albumin (P < 0.01), total protein (P = 0.03), urea (P = 0.04), lipopolysaccharide (P < 0.01), β-hydroxybutyric acid (P = 0.02), interleukin-1β (IL-1β) (P < 0.01), IL-4 (P < 0.01), and tumor necrosis factor α (P < 0.01) were affected by age. The abundance of Prevotella was lower (P < 0.05), whereas Megasphaera (P < 0.05) was greater in the EAF group compared to the LAF group at 42 d of age. The early addition of alfalfa promotes rumen epithelial microbiota colonization. In conclusion, this study demonstrated that alfalfa provision at 14 d of age promotes growth performance in lambs, but this effect disappeared at 43 to 70 d of age. Moreover, provision of alfalfa at 14 d of age enhances the immune response, promotes rumen tissue cell proliferation, and affects dynamical changes of rumen epithelial microbiota. Meanwhile, our findings showed that the rumen undergoes significant physiological challenges during the transition from a liquid diet to a solid diet.

Investigations of microbiota composition and neuroactive pathways in association with symptoms of stress and depression in a cohort of healthy women.

Despite mounting evidence of gut-brain involvement in psychiatric conditions, functional data remain limited, and analyses of other microbial niches, such as the vaginal microbiota, are lacking in relation to mental health. This aim of this study was to investigate if the connections between the gut microbiome and mental health observed in populations with a clinical diagnosis of mental illness extend to healthy women experiencing stress and depressive symptoms. Additionally, this study examined the functional pathways of the gut microbiota according to the levels of psychological symptoms. Furthermore, the study aimed to explore potential correlations between the vaginal microbiome and mental health parameters in young women without psychiatric diagnoses. In this cross-sectional study, 160 healthy Danish women (aged 18-40 years) filled out questionnaires with validated scales measuring symptoms of stress and depression and frequency of dietary intake. Fecal and vaginal microbiota samples were collected at the beginning of the menstrual cycle and vaginal samples were also collected at cycle day 8-12 and 18-22. Shotgun metagenomic profiling of the gut and vaginal microbiome was performed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) was used for functional profiling and 56 Gut Brain Modules were analyzed in the fecal samples. The relative abundance in the gut of the genera Escherichia, Parabacteroides, and Shigella was higher in women with elevated depressive symptoms. Women with high perceived stress showed a tendency of increased abundance of Escherichia, Shigella, and Blautia. Amongst others, the potentially pathogenic genera, Escherichia and Shigella correlate with alterations in the neuroactive pathways such as the glutamatergic, GABAeric, dopaminergic, and Kynurenine pathways. Vaginosis symptoms were more prevalent in women reporting high levels of stress and depressive symptoms. The findings of this study support the concept of a microbiota-associated effect on the neuroactive pathways even in healthy young women. This suggest, that targeting the gut microbiome could be a promising approach for future psychiatric interventions.