-
Environmental Research Jun 2024Animal and human studies indicate that exposure to air pollution and natural environments might modulate the gut microbiota, but epidemiological evidence is very scarce.
BACKGROUND
Animal and human studies indicate that exposure to air pollution and natural environments might modulate the gut microbiota, but epidemiological evidence is very scarce.
OBJECTIVES
To assess the potential impact of pre- and postnatal exposure to air pollution and green spaces on infant gut microbiota assembly and trajectories during the first year of life.
METHODS
MAMI ("MAternal MIcrobes") birth cohort (Valencia, Spain, N = 162) was used to study the impact of environmental exposure (acute and chronic) on infant gut microbiota during the first year of life (amplicon-based 16S rRNA sequencing). At 7 days and at 1, 6 and 12 months, residential pre- and postnatal exposure to air pollutants (NO, black carbon -BC-, PM and O) and green spaces indicators (NDVI and area of green spaces at 300, 500 and 1000 m buffers) were obtained. For the association between exposures and alpha diversity indicators linear regression models (cross-sectional analyses) and mixed models, including individual as a random effect (longitudinal analyses), were applied. For the differential taxon analysis, the ANCOM-BC package with a log count transformation and multiple-testing corrections were used.
RESULTS
Acute exposure in the first week of life and chronic postnatal exposure to NO were associated with a reduction in microbial alpha diversity, while the effects of green space exposure were not evident. Acute and chronic (prenatal or postnatal) exposure to NO resulted in increased abundance of Haemophilus, Akkermansia, Alistipes, Eggerthella, and Tyzerella populations, while increasing green space exposure associated with increased Negativicoccus, Senegalimassilia and Anaerococcus and decreased Tyzzerella and Lachnoclostridium populations.
DISCUSSION
We observed a decrease in the diversity of the gut microbiota and signs of alteration in its composition among infants exposed to higher levels of NO. Increasing green space exposure was also associated with changes in gut microbial composition. Further research is needed to confirm these findings.
PubMed: 38830395
DOI: 10.1016/j.envres.2024.119283 -
Frontiers in Microbiology 2024Sepsis is commonly associated with a sudden impairment of brain function, thus leading to significant rates of illness and mortality. The objective of this research was...
BACKGROUND
Sepsis is commonly associated with a sudden impairment of brain function, thus leading to significant rates of illness and mortality. The objective of this research was to integrate microbiome and metabolome to reveal the mechanism of microbiota-hippocampus-metabolites axis dysfunction in a mouse model of sepsis.
METHODS
A mouse model of sepsis was established via cecal ligation and puncture. The potential associations between the composition of the gut microbiota and metabolites in the hippocampus of mice with sepsis were investigated by combining 16S ribosomal RNA gene sequencing and ultra-high-performance liquid chromatography tandem mass spectrometry.
RESULTS
A total of 140 differential metabolites were identified in the hippocampal tissues of mice with sepsis when compared to those of control mice. These differential metabolites in mice with sepsis were not only associated with autophagy and serotonergic synapse, but also involved in the metabolism and synthesis of numerous amino acids. At the phylum level, the abundance of was increased, while that of () was decreased in mice with sepsis. At the genus level, the abundance of was increased, while that of was decreased in mice with sepsis. The ()/ (F/B) ratio was decreased in mice with sepsis when compared to that of control mice. Furthermore, the F/B ratio was positively correlated with 5'-methylthioadenosine, PC (18:3(9Z,12Z,15Z)/18:0) and curdione, and negatively correlated with indoxylsulfuric acid, corticosterone, kynurenine and ornithine.
CONCLUSION
Analysis revealed a reduction in the F/B ratio in mice with sepsis, thus contributing to the disturbance of 5'-methylthioadenosine, curdione, PC (18:3(9Z,12Z,15Z)/18:0), corticosterone, ornithine, indoxylsulfuric acid and kynurenine; eventually, these changes led to hippocampus dysfunction. Our findings provide a new direction for the management of sepsis-induced hippocampus dysfunction.
PubMed: 38827158
DOI: 10.3389/fmicb.2024.1302907 -
Applied Microbiology and Biotechnology Jun 2024The gastrointestinal tract (GIT) is stationed by a dynamic and complex microbial community with functions in digestion, metabolism, immunomodulation, and reproduction....
The gastrointestinal tract (GIT) is stationed by a dynamic and complex microbial community with functions in digestion, metabolism, immunomodulation, and reproduction. However, there is relatively little research on the composition and function of microorganisms in different GIT segments in dairy goats. Herein, 80 chyme samples were taken from ten GIT sites of eight Xinong Saanen dairy goats and then analyzed and identified the microbial composition via 16S rRNA V1-V9 amplicon sequencing. A total of 6669 different operational taxonomic units (OTUs) were clustered, and 187 OTUs were shared by ten GIT segments. We observed 264 species belonging to 23 different phyla scattered across ten GITs, with Firmicutes (52.42%) and Bacteroidetes (22.88%) predominating. The results revealed obvious location differences in the composition, diversity, and function of the GIT microbiota. In LEfSe analysis, unidentified_Lachnospiraceae and unidentified_Succinniclassicum were significantly enriched in the four chambers of stomach, with functions in carbohydrate fermentation to compose short-chain fatty acids. Aeriscardovia, Candidatus_Saccharimonas, and Romboutsia were significantly higher in the foregut, playing an important role in synthesizing enzymes, amino acids, and vitamins and immunomodulation. Akkermansia, Bacteroides, and Alistipes were significantly abundant in the hindgut to degrade polysaccharides and oligosaccharides, etc. From rumen to rectum, α-diversity decreased first and then increased, while β-diversity showed the opposite trend. Metabolism was the major function of the GIT microbiome predicted by PICRUSt2, but with variation in target substrates along the regions. In summary, GIT segments play a decisive role in the composition and functions of microorganisms. KEY POINTS: • The jejunum and ileum were harsh for microorganisms to colonize due to the presence of bile acids, enzymes, faster chyme circulation, etc., exhibiting the lowest α-diversity and the highest β-diversity. • Variability in microbial profiles between the three foregut segments was greater than four chambers of stomach and hindgut, with a higher abundance of Firmicutes dominating than others. • Dairy goats dominated a higher abundance of Kiritimatiellaeota than cows, which was reported to be associated with fatty acid synthesis.
Topics: Animals; Goats; Gastrointestinal Microbiome; Gastrointestinal Tract; RNA, Ribosomal, 16S; Bacteria; Phylogeny; DNA, Bacterial; Biodiversity; Female
PubMed: 38822843
DOI: 10.1007/s00253-024-13200-8 -
New Microbes and New Infections Jun 2024
Expression of Concern: Corynebacterium pacaense sp. nov., Alistipes megaguti sp. nov., Alistipes provencensis sp. nov., 3 new bacteria isolated from fresh human stool specimens.
PubMed: 38799971
DOI: 10.1016/j.nmni.2024.101290 -
International Journal of Molecular... May 2024Gut microbiota imbalances have a significant role in the pathogenesis of Inflammatory Bowel Disease (IBD) and Non-Alcoholic Fatty Liver Disease (NAFLD). Herein, we...
Gut microbiota imbalances have a significant role in the pathogenesis of Inflammatory Bowel Disease (IBD) and Non-Alcoholic Fatty Liver Disease (NAFLD). Herein, we compared gut microbial composition in patients diagnosed with either IBD or NAFLD or a combination of both. Seventy-four participants were stratified into four groups: IBD-NAFLD, IBD-only, NAFLD-only patients, and healthy controls (CTRLs). The 16S rRNA was sequenced by Next-Generation Sequencing. Bioinformatics and statistical analysis were performed. Bacterial α-diversity showed a significant lower value when the IBD-only group was compared to the other groups and particularly against the IBD-NAFLD group. β-diversity also showed a significant difference among groups. The higher Bacteroidetes/Firmicutes ratio was found only when comparing IBD groups and CTRLs. Comparing the IBD-only group with the IBD-NAFLD group, a decrease in differential abundance of Subdoligranulum, Parabacteroides, and Fusicatenibacter was found. Comparing the NAFLD-only with the IBD-NAFLD groups, there was a higher abundance of Alistipes, Odoribacter, Sutterella, and Lachnospira. An inverse relationship in the comparison between the IBD-only group and the other groups was shown. For the first time, the singularity of the gut microbial composition in IBD and NAFLD patients has been shown, implying a potential microbial signature mainly influenced by gut inflammation.
Topics: Humans; Non-alcoholic Fatty Liver Disease; Gastrointestinal Microbiome; Inflammatory Bowel Diseases; Female; Male; Middle Aged; Adult; Metagenomics; RNA, Ribosomal, 16S; Bacteria; Metagenome
PubMed: 38791490
DOI: 10.3390/ijms25105453 -
Biomedicines May 2024The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has significantly impacted global healthcare, underscoring the importance of exploring the virus's effects on...
The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has significantly impacted global healthcare, underscoring the importance of exploring the virus's effects on infected individuals beyond treatments and vaccines. Notably, recent findings suggest that SARS-CoV-2 can infect the gut, thereby altering the gut microbiota. This study aimed to analyze the gut microbiota composition differences between COVID-19 patients experiencing mild and severe symptoms. We conducted 16S rRNA metagenomic sequencing on fecal samples from 49 mild and 43 severe COVID-19 cases upon hospital admission. Our analysis identified a differential abundance of specific bacterial species associated with the severity of the disease. Severely affected patients showed an association with , , and others, while milder cases were linked to , , , and additional species. Furthermore, a network analysis using SPIEC-EASI indicated keystone taxa and highlighted structural differences in bacterial connectivity, with a notable disruption in the severe group. Our study highlights the diverse impacts of SARS-CoV-2 on the gut microbiome among both mild and severe COVID-19 patients, showcasing a spectrum of microbial responses to the virus. Importantly, these findings align, to some extent, with observations from other studies on COVID-19 gut microbiomes, despite variations in methodologies. The findings from this study, based on retrospective data, establish a foundation for future prospective research to confirm the role of the gut microbiome as a predictive biomarker for the severity of COVID-19.
PubMed: 38790958
DOI: 10.3390/biomedicines12050996 -
Frontiers in Microbiology 2024The host genes play a crucial role in shaping the composition and structure of the gut microbiome. Red deer is listed as an endangered species by the International Union...
The host genes play a crucial role in shaping the composition and structure of the gut microbiome. Red deer is listed as an endangered species by the International Union for the Conservation of Nature, and its pilose antlers have good medicinal value. Hybridization can lead to heterosis, resulting in increased pilose antler production and growth performance in hybrid deer. However, the role of the gut microbiome in hybrid deer remains largely unknown. In this study, alpha and beta diversity analysis showed that hybridization altered the composition and structure of the gut microbiome of the offspring, with the composition and structure of the hybrid offspring being more similar to those of the paternal parents. Interestingly, the LefSe differential analysis showed that there were some significantly enriched gut microbiome in the paternal parents (such as , , etc.) and the maternal parents (including , , etc.), which remained significantly enriched in the hybrid offspring. Additionally, the hybrid offspring exhibited a significant advantage over the parental strains, particularly in taxa that can produce short-chain fatty acids, such as , , and . Similar to bacterial transmission, metagenomic analysis showed that some signaling pathways related to pilose antler growth ("Wnt signaling pathway," "PI3K Akt signaling pathway," "MAPK signaling pathway") were also enriched in hybrid red deer after hybridization. Furthermore, metabolomic analysis revealed that compared with the paternal and maternal parents, the hybrid offspring exhibited significant enrichment in metabolites related to "Steroid hormone biosynthesis," "Tryptophan metabolism," "Valine, leucine and isoleucine metabolism," and "Vitamin B metabolism." Notably, the metagenomic analysis also showed that these metabolic pathways were significantly enriched in hybrid deer. Finally, a correlation analysis between the gut microbiome and metabolites revealed a significant positive correlation between the enriched taxa in hybrid deer, including the , , and , and metabolites, such as 7α-hydroxytestosterone, L-kynurenine, indole, L-isoleucine, and riboflavin. The study contributes valuable data toward understanding the role of the gut microbiome from red deer in hybridization and provides reference data for further screening potential probiotics and performing microbial-assisted breeding that promotes the growth of red deer pilose antlers and bodies, development, and immunity.
PubMed: 38784815
DOI: 10.3389/fmicb.2024.1387957 -
Scientific Reports May 2024This study aimed to explore the gut microbiota characteristics of ischemic and hemorrhagic stroke patients. A case-control study was conducted, and high-throughput...
This study aimed to explore the gut microbiota characteristics of ischemic and hemorrhagic stroke patients. A case-control study was conducted, and high-throughput sequencing of the V4-V5 region of 16S rRNA was used to analyze the differences in gut microbiota. The results showed that Proteobacteria was significantly increased in the ischemic stroke group compared with the healthy control group, while Fusobacteria was significantly increased in the hemorrhagic stroke group. In the ischemic stroke group, Butyricimonas, Alloprevotella, and Escherichia were significantly more abundant than in the healthy control group. In the hemorrhagic stroke group, Atopobium, Hungatella, Eisenbergiella, Butyricimonas, Odonbacter, Lachnociostridium, Alistipes, Parabacteroides, and Fusobacterium were significantly more abundant than in the healthy control group. Additionally, Alloprevotella, Ruminococcus, and Prevotella were significantly more abundant in the ischemic stroke group than in the hemorrhagic stroke group. The gut microbiota of ischemic and hemorrhagic stroke patients has significant diversity characteristics. These results provide new theoretical basis for exploring the prevention and treatment of different types of stroke through gut microbiota research.
Topics: Gastrointestinal Microbiome; Humans; Ischemic Stroke; Male; Hemorrhagic Stroke; Female; Case-Control Studies; Middle Aged; RNA, Ribosomal, 16S; Aged; Bacteria; High-Throughput Nucleotide Sequencing
PubMed: 38782999
DOI: 10.1038/s41598-024-62606-x -
Frontiers in Endocrinology 2024Polycystic Ovary Syndrome (PCOS) is a heritable condition with an as yet unclear etiology. Various factors, such as genetics, lifestyle, environment, inflammation,...
BACKGROUND
Polycystic Ovary Syndrome (PCOS) is a heritable condition with an as yet unclear etiology. Various factors, such as genetics, lifestyle, environment, inflammation, insulin resistance, hyperandrogenism, iron metabolism, and gut microbiota, have been proposed as potential contributors to PCOS. Nevertheless, a systematic assessment of modifiable risk factors and their causal effects on PCOS is lacking. This study aims to establish a comprehensive profile of modifiable risk factors for PCOS by utilizing a two-sample Mendelian Randomization (MR) framework.
METHODS
After identifying over 400 modifiable risk factors, we employed a two-sample MR approach, including the Inverse Variance Weighted (IVW) method, Weighted Median method, and MR-Egger, to investigate their causal associations with PCOS. The reliability of our estimates underwent rigorous examination through sensitivity analyses, encompassing Cochran's Q test, MR-Egger intercept analysis, leave-one-out analysis, and funnel plots.
RESULTS
We discovered that factors such as smoking per day, smoking initiation, body mass index, basal metabolic rate, waist-to-hip ratio, whole body fat mass, trunk fat mass, overall health rating, docosahexaenoic acid (DHA) (22:6n-3) in blood, monounsaturated fatty acids, other polyunsaturated fatty acids apart from 18:2 in blood, omega-3 fatty acids, ratio of bisallylic groups to double bonds, omega-9 and saturated fatty acids, total lipids in medium VLDL, phospholipids in medium VLDL, phospholipids in very large HDL, triglycerides in very large HDL, the genus , the genus , the genus 9, the class , and the phylum , showed a significant effect on heightening genetic susceptibility of PCOS. In contrast, factors including fasting insulin interaction with body mass index, sex hormone-binding globulin, iron, ferritin, SDF1a, college or university degree, years of schooling, household income, the genus , the family , the order , the class , and the phylum were determined to reduce risk of PCOS.
CONCLUSION
This study innovatively employs the MR method to assess causal relationships between 400 modifiable risk factors and the susceptibility of PCOS risk. It supports causal links between factors like smoking, BMI, and various blood lipid levels and PCOS. These findings offer novel insights into potential strategies for the management and treatment of PCOS.
Topics: Polycystic Ovary Syndrome; Humans; Female; Mendelian Randomization Analysis; Risk Factors; Body Mass Index; Insulin Resistance
PubMed: 38779450
DOI: 10.3389/fendo.2024.1348368 -
Animal Nutrition (Zhongguo Xu Mu Shou... Jun 2024The effects of xylo-oligosaccharides (XOS) on broiler growth performance, immune function, and intestinal health were investigated. A total of 540 one-d-old Arbor Acres...
The effects of xylo-oligosaccharides (XOS) on broiler growth performance, immune function, and intestinal health were investigated. A total of 540 one-d-old Arbor Acres Plus broilers were randomly divided into 5 groups with 6 replicates per group and 18 chickens per replicate. Broilers in the control (CON) group received a corn-soybean meal based basal diet, those in the antibiotics (ANT) group received the basal diet plus 500 mg/kg oxytetracycline, and those in XOS groups received the basal diet plus 150, 300, or 450 mg/kg XOS. Compared with CON, the body weight at 42 d and average daily gain from 1 to 42 d were significantly increased in the 150, 450 mg/kg XOS-added and ANT groups ( = 0.018), and the relative expression of claudin-1 and 1 mRNA in the ileum was significantly higher in the 300 and 450 mg/kg XOS-added groups ( < 0.001). The feed conversion ratios ( < 0.001) and abdominal fat rates ( = 0.012) of broilers from 1 to 42 d of age were significantly lower in all XOS-added groups than in the control group. Splenic index ( = 0.036) and bursa of Fabricius index ( = 0.009) were significantly better in the ANT group and each XOS-added group than in the control group. Compared to CON and ANT, serum IgA ( = 0.007) and IgG ( = 0.002) levels were significantly higher in the 300 mg/kg XOS-added group, and the relative abundance of short-chain fatty acid-producing genera () was also significantly higher ( < 0.001). Meanwhile, ileal villus height ( < 0.001) and ratio of villus height to crypt depth (V:C) ( = 0.001) were significantly increased in XOS-added broilers. In analysis of relationships between cecal microbes and the physical barrier of the gut, was positively correlated with mRNA expression of ileal and claudin-1 ( < 0.05), and was positively correlated with increased ileal villus height and V:C ( < 0.05). Overall, XOS addition to broiler diets improved growth performance, promoted intestinal health by enhancing intestinal barrier function and regulating cecal microbiota diversity, and had positive effects on immunity.
PubMed: 38779325
DOI: 10.1016/j.aninu.2024.01.004