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Translational Animal Science 2023Our objective was to evaluate the effects of combinations of and as direct-fed microbials (DFM) on ruminal microbiome during an acute acidosis challenge in a...
Our objective was to evaluate the effects of combinations of and as direct-fed microbials (DFM) on ruminal microbiome during an acute acidosis challenge in a continuous culture system. Treatments provided a DFM dose of 1 × 10 colony-forming unit (CFU)/mL, as follows: control (no DFM), YM1 ( and strain 1), YM2 ( and strain 2), and YMM ( and half of the doses of strains 1 and 2). We conducted four experimental periods of 11 d, which consisted of non-acidotic days (1 to 8) and acidotic challenge days (9 to 11) to establish acute ruminal acidosis conditions with a common basal diet containing 12% neutral detergent fiber and 58% starch. Treatments were applied from days 8 to 11, and samples of liquid and solid-associated bacteria were collected on days 9 to 11. Overall, 128 samples were analyzed by amplification of the V4 region of bacterial 16S rRNA, and data were analyzed with R and SAS for alpha and beta diversity, taxa relative abundance, and correlation of taxa abundance with propionate molar proportion. We observed a lower bacterial diversity (Shannon index, = 0.02) when YM1 was added to the diet in comparison to the three other treatments. Moreover, compared to control, addition of YM1 to the diet increased relative abundance of phylum ( = 0.05) and family ( = 0.05) in the solid fraction and tended to increase abundance of family ( = 0.10) and genus ( = 0.09) in the liquid fraction. Correlation analysis indicated a positive association between propionate molar proportion and relative abundance of ( = 0.36, = 0.04) and ( = 0.36, = 0.05) in the solid fraction. The inclusion of YM1 in high-grain diets with a high starch content resulted in greater abundance of bacteria involved in succinate synthesis which may have provided the substrate for the greater propionate synthesis observed.
PubMed: 38023425
DOI: 10.1093/tas/txad123 -
Microbial Pathogenesis Oct 2023The etiology remains to be understood for endometriosis (EMS) which affected health negatively for 10% of reproductive-age women globally. Emerging studies found the...
The etiology remains to be understood for endometriosis (EMS) which affected health negatively for 10% of reproductive-age women globally. Emerging studies found the associations of EMS with genital microbiota dysbiosis. However, the role of vaginal and cervical microbiota is not fully understood for Chinese women. This study recruited forty Chinese women (21 healthy women and 19 EMS patients) to analyze vaginal and cervical microbiota using 16S rRNA amplicon sequencing method. For both sites, there were no significant differences for distribution of microbial samples between control and EMS group, which was concordant with dominated Lactobacillus in both groups. In contrast, we observed accumulation of several low-abundance genera in vaginal and cervical microbiota of EMS patients, such as Fannyhessea, Prevotella, Streptococcus, Bifidobacterium, Veillonella, Megasphaera and Sneathia. Random forest analysis found that translocation of these genera had the significant importance in differentiating EMS patients from controls. In addition, cervix/vagina ratio of these genera also associated with EMS severity. And these genera had notable associations with ascending infection-related functional pathways, including flagellar assembly, bacterial motility proteins, bacterial toxins and epithelial cell signaling in Helicobacter pylori infection. These findings suggest that translocation of specific genera between vaginal and cervical sites play a role in EMS.
Topics: Humans; Female; Cervix Uteri; Pilot Projects; Endometriosis; Lactobacillus; RNA, Ribosomal, 16S; Helicobacter Infections; Helicobacter pylori; Vagina; Bacterial Proteins
PubMed: 37586463
DOI: 10.1016/j.micpath.2023.106309 -
Schizophrenia Bulletin Sep 2023Intestinal microbiota is intrinsically linked to human health. Evidence suggests that the composition and function of the microbiome differs in those with schizophrenia... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND HYPOTHESIS
Intestinal microbiota is intrinsically linked to human health. Evidence suggests that the composition and function of the microbiome differs in those with schizophrenia compared with controls. It is not clear how these alterations functionally impact people with schizophrenia. We performed a systematic review and meta-analysis to combine and evaluate data on compositional and functional alterations in microbiota in patients with psychosis or schizophrenia.
STUDY DESIGN
Original studies involving humans and animals were included. The electronic databases PsycINFO, EMBASE, Web of Science, PubMed/MEDLINE, and Cochrane were systematically searched and quantitative analysis performed.
STUDY RESULTS
Sixteen original studies met inclusion criteria (1376 participants: 748 cases and 628 controls). Ten were included in the meta-analysis. Although observed species and Chao 1 show a decrease in diversity in people with schizophrenia compared with controls (SMD = -0.14 and -0.66 respectively), that did not reach statistical significance. We did not find evidence for variations in richness or evenness of microbiota between patients and controls overall. Differences in beta diversity and consistent patterns in microbial taxa were noted across studies. We found increases in Bifidobacterium, Lactobacillus, and Megasphaera in schizophrenia groups. Variations in brain structure, metabolic pathways, and symptom severity may be associated with compositional alterations in the microbiome. The heterogeneous design of studies complicates a similar evaluation of functional readouts.
CONCLUSIONS
The microbiome may play a role in the etiology and symptomatology of schizophrenia. Understanding how the implications of alterations in microbial genes for symptomatic expression and clinical outcomes may contribute to the development of microbiome targeted interventions for psychosis.
Topics: Humans; Schizophrenia; Gastrointestinal Microbiome; Psychotic Disorders
PubMed: 37210594
DOI: 10.1093/schbul/sbad049 -
Journal of Animal Science and... Aug 2023Ginkgo biloba extract (GBE) is evidenced to be effective in the prevention and alleviation of metabolic disorders, including obesity, diabetes and fatty liver disease....
BACKGROUND
Ginkgo biloba extract (GBE) is evidenced to be effective in the prevention and alleviation of metabolic disorders, including obesity, diabetes and fatty liver disease. However, the role of GBE in alleviating fatty liver hemorrhagic syndrome (FLHS) in laying hens and the underlying mechanisms remain to be elucidated. Here, we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut microbiota.
RESULTS
The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet (HFD)-induced FLHS laying hen model by decreasing the levels of TG, TC, ALT and ALP. The lipid accumulation and pathological score of liver were also relieved after GBE treatment. Moreover, GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH, SOD, T-AOC, GSH-PX and reducing MDA, and downregulated the expression of genes related to lipid synthesis (FAS, LXRα, GPAT1, PPARγ and ChREBP1) and inflammatory cytokines (TNF-α, IL-6, TLR4 and NF-κB) in the liver. Microbial profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota, particularly elevated the abundance of Megasphaera in the cecum. Meanwhile, targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs, acetate and propionate, which were positively correlated with the GBE-enriched gut microbiota. Finally, we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation (FMT).
CONCLUSIONS
We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut microbiota. Our findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry.
PubMed: 37533076
DOI: 10.1186/s40104-023-00900-w -
International Journal of Molecular... Aug 2023Imbalance of the immune system caused by alterations of the gut microbiome is considered to be a critical factor in the pathogenesis of infant eczema, but the exact role...
Imbalance of the immune system caused by alterations of the gut microbiome is considered to be a critical factor in the pathogenesis of infant eczema, but the exact role of the gut microbiome in adult atopic dermatitis (AD) patients remains to be clarified. To investigate the differences of the gut microbiome between adult AD patients and healthy individuals, stool samples of 234 adults, containing 104 AD patients and 130 healthy subjects, were collected for 16S rRNA gene amplicon. Altered structure and metabolic dysfunctions of the gut microbiome were identified in adult AD patients. Our results illustrated that the adult AD patients were more likely to have allergies, particularly non-food allergies. In addition, the gut microbiome composition of the AD and normal groups were considerably different. Moreover, and was enriched in the normal group, whereas , , , , , , , and dominated in the AD group. Additionally, purine nucleotide degradation pathways were significantly enriched in the AD group, and the enrichment of proteinogenic amino acid biosynthesis pathways was found in the normal group. This study provides insights into new therapeutic strategies targeting the gut microbiome for AD and evidence for the involvement of the gut-skin axis in AD patients.
Topics: Infant; Humans; Adult; Dermatitis, Atopic; Gastrointestinal Microbiome; East Asian People; RNA, Ribosomal, 16S; Hypersensitivity; Clostridiaceae; Lactobacillales
PubMed: 37629036
DOI: 10.3390/ijms241612856 -
Journal of Crohn's & Colitis Jul 2023Crohn's disease [CD] is a major subtype of inflammatory bowel diseases [IBD] with increasing incidence and prevalence. Results of studies using available small and large...
BACKGROUND AND AIMS
Crohn's disease [CD] is a major subtype of inflammatory bowel diseases [IBD] with increasing incidence and prevalence. Results of studies using available small and large animal models are often poorly translatable to patients, and few CD models show small intestinal pathology. Due to its similarities to humans, the pig has emerged as a highly suitable translational disease model, particularly for testing novel nutritional and technological interventions. Our goal was to develop a physiologically relevant porcine CD model to facilitate translation of findings and interventions towards the clinic.
METHODS
We generated pigs bearing a 93-bp deletion of the adenosine-uracil-rich element [ARE] and a constitutive-decay element within the 3' untranslated region of the TNF gene. Comparative analysis of physiological, molecular, histological and microbial characteristics was performed between wild-type, TNFΔARE/+ and TNFΔARE/ΔARE animals. Alterations in the microbiome were compared to the TNFΔARE mouse model and IBD patients.
RESULTS
TNF ΔARE pigs recapitulate major characteristics of human CD, including ulcerative transmural ileocolitis, increased abundance of proinflammatory cytokines, immune cell infiltration and dysbiotic microbial communities. 16S rRNA gene amplicon sequencing revealed enrichment in members belonging to Megasphaera, Campylobacter, Desulfovibrio, Alistipes and Lachnoclostridum in faecal or mucosa-associated bacteria compared to wild-type littermates. Principal components analysis clustering with a subset of TNFΔARE/+ mice and human IBD patients suggests microbial similarity based on disease severity.
CONCLUSIONS
We demonstrate that the TNFΔARE pig resembles a CD-like ileocolitis pathophenotype recapitulating human disease. The ability to conduct long-term studies and test novel surgical procedures and dietary interventions in a physiologically relevant model will benefit future translational IBD research studies.
Topics: Humans; Animals; Mice; Swine; Crohn Disease; RNA, Ribosomal, 16S; Tumor Necrosis Factor-alpha; Ileitis; Inflammatory Bowel Diseases
PubMed: 36821422
DOI: 10.1093/ecco-jcc/jjad034 -
Microorganisms Jan 2024The Gram-negative, strictly anaerobic bacterium was first isolated from the rumen in 1953 and is common in the mammalian gastrointestinal tract. Its ability to use... (Review)
Review
The Gram-negative, strictly anaerobic bacterium was first isolated from the rumen in 1953 and is common in the mammalian gastrointestinal tract. Its ability to use either lactate or glucose as its major energy sources for growth has been well documented, although it can also ferment amino acids into ammonia and branched-chain fatty acids, which are growth factors for other bacteria. The ruminal abundance of usually increases in animals fed grain-based diets due to its ability to use lactate (the product of rapid ruminal sugar fermentation), especially at a low ruminal pH (<5.5). has been proposed as a potential dietary probiotic to prevent ruminal acidosis in feedlot cattle and high-producing dairy cows. However, this bacterium has also been associated with milk fat depression (MFD) in dairy cows, although proving a causative role has remained elusive. This review summarizes the unique physiology of this intriguing bacterium and its functional role in the ruminal community as well as its role in the health and productivity of the host animal. In addition to its effects in the rumen, the ability of to produce C-C carboxylic acids-potential precursors for industrial fuel and chemical production-is examined.
PubMed: 38276203
DOI: 10.3390/microorganisms12010219 -
Frontiers in Microbiology 2023Understanding the relationships between social stress and the gastrointestinal microbiota, and how they influence host health and performance is expected to have many...
Understanding the relationships between social stress and the gastrointestinal microbiota, and how they influence host health and performance is expected to have many scientific and commercial implementations in different species, including identification and improvement of challenges to animal welfare and health. In particular, the study of the stress impact on the gastrointestinal microbiota of pigs may be of interest as a model for human health. A porcine stress model based on repeated regrouping and reduced space allowance during the last 4 weeks of the finishing period was developed to identify stress-induced changes in the gut microbiome composition. The application of the porcine stress model resulted in a significant increase in salivary cortisol concentration over the course of the trial and decreased growth performance and appetite. The applied social stress resulted in 32 bacteria being either enriched (13) or depleted (19) in the intestine and feces. Fecal samples showed a greater number of microbial genera influenced by stress than caecum or colon samples. Our trial revealed that the opportunistic pathogens and were enriched in colonic and fecal samples from stressed pigs. Additionally, genera such as , , , , , and were found to be enriched in response to social stress. In contrast, the genera , , , , , , and were depleted. These depleted bacteria are of great interest because they synthesize metabolites [e.g., short-chain fatty acids (SCFA), in particular, butyrate] showing beneficial health benefits due to inhibitory effects on pathogenic bacteria in different animal species. Of particular interest are and , as their depletion was identified in a human study to be associated with inferior quality of life and depression. We also revealed that some pigs were more susceptible to pathogens as indicated by large enrichments of opportunistic pathogens of and . Generally, our results provide further evidence for the microbiota-gut-brain axis as indicated by an increase in cortisol concentration due to social stress regulated by the hypothalamic-pituitary-adrenal axis, and a change in microbiota composition, particularly of bacteria known to be associated with pathogenicity and mental health diseases.
PubMed: 38029169
DOI: 10.3389/fmicb.2023.1197371 -
Applied and Environmental Microbiology Jan 2024Butyrate, a physiologically active molecule, can be synthesized through metabolic interactions among colonic microorganisms. Previously, in a fermenting trial of human...
Butyrate, a physiologically active molecule, can be synthesized through metabolic interactions among colonic microorganisms. Previously, in a fermenting trial of human fecal microbiota, we observed that the butyrogenic effect positively correlated with the increasing population and an unidentified species. Therefore, we hypothesized that a cross-feeding phenomenon exists between and , where is the butyrate producer, and its growth relies on the metabolites generated by . To validate this hypothesis, three bacterial species (, , and ) were isolated from fecal cultures fermenting hydrolyzed xylan; pairwise cocultures were conducted between the and isolates; the microbial interactions were determined based on bacterial genome information, cell growth, substrate consumption, metabolite quantification, and metatranscriptomics. The results indicated that two isolates contained distinct gene clusters for xylan utilization and expressed varying substrate preferences. In contrast, alone scarcely grew on the xylose-based substrates. The growth of was significantly elevated by coculturing it with bifidobacteria, while the two species responded differently in the kinetics of cell growth and substrate consumption. Coculturing led to the depletion of lactate and increased the formation of butyrate. An RNA-seq analysis further revealed the upregulation of genes involved in the lactate utilization and butyrate formation pathways. We concluded that lactate generated by through catabolizing xylose fueled the growth of and triggered the synthesis of butyrate. Our findings demonstrated a novel cross-feeding mechanism to generate butyrate in the human colon.IMPORTANCEButyrate is an important short-chain fatty acid that is produced in the human colon through microbial fermentation. Although many butyrate-producing bacteria exhibit a limited capacity to degrade nondigestible food materials, butyrate can be formed through cross-feeding microbial metabolites, such as acetate or lactate. Previously, the literature has explicated the butyrate-forming links between and and between and . In this study, we provided an alternative butyrate synthetic pathway through the interaction between and is a species named in 2014 and is indigenous to the human intestinal tract. Scientific studies explaining the function of in the human colon are still limited. Our results show that proliferated based on the lactate generated by bifidobacteria and produced butyrate as its end metabolic product. The pathways identified here may contribute to understanding butyrate formation in the gut microbiota.
Topics: Humans; Lactic Acid; Bifidobacterium; Xylans; Xylose; Butyrates; Megasphaera; Fermentation
PubMed: 38126785
DOI: 10.1128/aem.01019-23 -
Biochimica Et Biophysica Acta.... Sep 2023Plasmalogens (Pls) are vinyl-ether bond-containing glycerophospholipids or glycosyl diradyl glycerols, and are of great importance in the physiological functions and...
Plasmalogens (Pls) are vinyl-ether bond-containing glycerophospholipids or glycosyl diradyl glycerols, and are of great importance in the physiological functions and stability of cell membrane. Here, we identified and characterized that the plasmalogen synthase MeHAD from anaerobic Megasphaera elsdenii was responsible for vinyl-ether bond formation. Different from the 2-hydroxyacyl-CoA dehydratase (HAD) family plasmalogen synthase PlsA-PlsR which are encoded by two genes in Clostridium perfringens, the HAD homolog (MeHAD) encoded by a single gene MELS_0169 was found in M. elsdenii. By heterologous expression of the MeHAD gene into a nonplasmalogen-producing Escherichia coli strain, the expressed MeHAD was found to be located in the cell membrane region. Plasmalogens were detected in the recombinant strain using GC-MS and LC-MS, demonstrating that MeHAD was the key enzyme for plasmalogen synthesis. Moreover, the synthesized plasmalogens could enhance the oxidative stress-resistance and osmotic pressure-resistance of the recombinant strain, probably due to the ROS scavenging and decreased membrane permeability by the plasmalogens, respectively. The four-cysteine (Cys125, Cys164, Cys445 and Cys484) site-mutant of MeHAD, which were predicted binding to the [4Fe-4S] cluster, was unable to synthesize plasmalogens, indicating that the cysteines are important for the catalytic activity of MeHAD. Our results revealed the single gene encoded plasmalogen synthase in M. elsdenii and established a recombinant E. coli strain with plasmalogen production potential.
Topics: Plasmalogens; Megasphaera elsdenii; Escherichia coli; Ethers
PubMed: 37348645
DOI: 10.1016/j.bbalip.2023.159358