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Scientific Reports Apr 2022Mycoplasma pneumoniae (MP) infection is a common cause of community-acquired pneumonia in children. Furthermore, many children with Mycoplasma pneumoniae pneumonia (MPP)...
Mycoplasma pneumoniae (MP) infection is a common cause of community-acquired pneumonia in children. Furthermore, many children with Mycoplasma pneumoniae pneumonia (MPP) have recurrent wheezing and reduced small airway function after their clinical symptoms have resolved, eventually leading to asthma. MPP can trigger immune disorders and systemic inflammatory responses. Hence, the intestine is the largest immune organ of the body. Therefore, we sought to investigate whether the alteration of intestinal flora is correlated with the development of wheezing in children with MPP. We collected 30 healthy children as group A, 50 children with nonwheezing MPP as group B, and 50 children with wheezing MPP as group C. We found that the percentage of eosinophil cells (EC) was significantly higher in group C than that in group B for routine blood tests and serum inflammatory factors. The serum cytokines, including IL-4, IL-17, TNF-α, and TGF-β, were significantly higher in group C than in group B. In addition, the level of IL-10 was significantly lower in group C than in group B. The distribution characteristics of intestinal flora strains in children with MPP were detected by sequencing of 16S rRNA gene amplicon sequencing. There were differences in the abundance of intestinal flora between children with MPP and healthy children, with lower abundance of Ruminococcus flavefaciens, Clostridium butyricum, Lactobacillus, and Bifidobacterium in the intestine of children with MPP compared to healthy children. The abundance of Ruminococcus flavefaciens and Clostridium butyricum was significantly lower in the intestine of children with wheezing MPP compared to children without wheezing MPP. In the correlation analysis between children with MPP and inflammatory factors, Ruminococcus flavefaciens was found to be negatively correlated with IL-17. Clostridium butyricum was negatively correlated with L-4, IL-17, TNF-α, and TGF-β; however, it positively correlated with IL-10. Thus, it was concluded that alterations in intestinal flora play a crucial role in the immune response to MPP, where a significant decline in intestinal Ruminococcus flavefaciens and Clostridium butyricum leads to an exacerbation of the inflammatory responses, which may promote the development of children with wheezing MPP.
Topics: Child; Gastrointestinal Microbiome; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; RNA, Ribosomal, 16S; Respiratory Sounds
PubMed: 35383237
DOI: 10.1038/s41598-022-09700-0 -
JHEP Reports : Innovation in Hepatology Jan 2023Sarcopenia and gut dysbiosis are common in individuals with cirrhosis. However, the association between sarcopenia and microbial alterations, and the subsequent impact...
BACKGROUND & AIMS
Sarcopenia and gut dysbiosis are common in individuals with cirrhosis. However, the association between sarcopenia and microbial alterations, and the subsequent impact on cirrhotic outcomes are poorly understood. This study aimed to identify muscle-dependent microbial changes and related risks of cirrhotic complications.
METHODS
From September 2018 to December 2020, 89 individuals with cirrhosis and 16 healthy volunteers were prospectively enrolled. Muscle and nutritional status, serum amino acids, and fecal microbiota were analyzed. The association between microbial signatures of sarcopenia and cirrhotic complications was investigated.
RESULTS
A decline in muscle mass and strength were associated with gut microbial alterations in individuals with cirrhosis. The greatest microbial dissimilarity was observed between those with sarcopenia (both decline in muscle mass and strength) and those with normal-muscle status ( = 0.035). Individuals with sarcopenia had lower serum levels of alanine, valine, leucine, isoleucine, proline, tryptophan and ornithine. Besides, gut microbial functions associated with amino acid biosynthesis were significantly reduced in individuals with sarcopenia and cirrhosis. Depletion of , and were associated with cirrhotic sarcopenia, and significantly correlated with the serum levels of amino acids. Individuals with coexistent depletion of and developed more infectious (44.4% . 3.0%) and non-infectious (74.1% 3.0%) complications, and more hospitalizations (54 3) than those with cirrhosis with good microbial signatures (all <0.001). In contrast, fecal enrichment of and independently decreased the risk of 1-year complications.
CONCLUSIONS
Sarcopenia-related fecal microbial alterations are associated with cirrhotic complications. These findings may facilitate measures to improve the outcomes of individuals with cirrhosis and sarcopenia by modifying gut microbiota.
IMPACT AND IMPLICATIONS
The composition and biosynthetic functions of gut microbiota are significantly changed in individuals with sarcopenic cirrhosis. Those with a sarcopenia-related poor microbial signature, in which and were both depleted, had significantly more infectious and non-infectious complications, as well as more hospitalizations. These findings highlight the therapeutic potential of modifying the gut microbiota of individuals with sarcopenic cirrhosis to improve their clinical outcomes.
PubMed: 36536957
DOI: 10.1016/j.jhepr.2022.100619 -
BioMed Research International 2021The subjects included 13 PI patients from the Hubei Provincial Hospital of TCM, Hubei University of TCM, and Wuhan Traditional Chinese Medicine Hospital, and the... (Clinical Trial)
Clinical Trial
METHODS
The subjects included 13 PI patients from the Hubei Provincial Hospital of TCM, Hubei University of TCM, and Wuhan Traditional Chinese Medicine Hospital, and the corresponding noninsomniac spouses of the patients were selected as controls. TWBXG was continuously administered for 4 weeks. The feces of PI patients and their noninsomniac spouses before and after treatment with TWBXG were collected. The intestinal flora composition of each group was detected by metagenomic sequencing, and the efficacy of TWBXG was evaluated by the PSQI scale.
RESULTS
Compared with the control group, the model group showed an increase in the abundance of Roseburia faecis, Ruminococcus, Prevotella copri, Fusicatenibacter saccharivorans, and Blautia obeum, while those of Bacteroides, fecal Bacteroidetes, and Faecalibacterium prausnitzii were decreased. Compared with pretreatment, the PSQI score was significantly reduced ( < 0.05), the abundance of Bacteroides, fecal Bacteroidetes, and Faecalibacterium prausnitzii increased, and that of Roseburia faecis, Ruminococcus, Prevotella copri, Fusicatenibacter saccharivorans, and Blautia obeum decreased after treatment. However, there was still a certain gap in the abundance of related flora in the treatment group compared with the control.
CONCLUSION
PI is associated with disturbances in the intestinal flora and is mainly related to the disorders of Roseburia faecis, Ruminococcus, Prevotella copri, Fusicatenibacter saccharivorans, Blautia obeum, Bacteroides, fecal Bacteroidetes, and Faecalibacterium prausnitzii. TWBXG can effectively treat PI, and its effect may be achieved by regulating the disordered intestinal flora. The study was registered in the Chinese clinical trial registry and approved by the World Health Organization clinical trial registration platform (Effects of the modified Tianwang Buxin granule and modified Tianwang Buxin decoction pieces on insomnia: a randomized, controlled trial, ChiCTR-IPR-17011549).
Topics: Adult; Case-Control Studies; Drugs, Chinese Herbal; Female; Gastrointestinal Microbiome; Hot Flashes; Humans; Male; Middle Aged; Perimenopause; Phytotherapy; Sleep Initiation and Maintenance Disorders
PubMed: 34825005
DOI: 10.1155/2021/9979511 -
Frontiers in Molecular Biosciences 2022IgA nephropathy (IgAN) is the most common type of glomerulonephritis in Asia. Its pathogenesis involves higher expression of galactose-deficient IgA1 (Gd-IgA1) and...
IgA nephropathy (IgAN) is the most common type of glomerulonephritis in Asia. Its pathogenesis involves higher expression of galactose-deficient IgA1 (Gd-IgA1) and dysregulated intestinal mucosal immunity. The objective of this study was to explore whether specific gut microbiota and associated enzymes affect Gd-IgA1 in IgAN. This study carried out shotgun metagenomic sequencing with Illumina on fecal samples collected from 20 IgAN patients (IgAN group) and 20 healthy controls (HCs group) who were recruited from January 2016 to December 2018 at the Second Clinical College of Guangzhou University of Chinese Medicine. Differences analysis in gut microbiota was performed to determine the overall microbiota composition, the representative enterotypes, and the microbiota abundance. Correlations between gut microbiota and clinical indicators were assessed by Spearman's analysis. Moreover, the functional prediction of microbial communities and the quantitative calculation of enzymes encoded by microbiome were performed using the MetaCyc pathway and the bioBakery three platform, respectively. and levels were higher, while and levels were lower in the IgAN group compared to HCs group. Enterotype I characterized by was closely related to the IgAN patients. Moreover, , and were characteristic bacteria enriched in IgAN patients. Spearman's correlation analysis found that and were positively correlated with urine protein-creatinine ratio, while showed a direct association with red blood cells in urine, and and were positively correlated with eGFR. These results indicated that intestinal dysbacteriosis occurred in IgAN patients and was associated with clinical and biochemical features. In addition, MetaCyc pathway analysis predicted microbiota-related metabolic pathways, including the biosynthesis of amino acids and glycans, were associated with the IgAN group. Microbial enzymes analysis highlighted that Gd-IgA1-associated α-galactosidase and α-N-acetyl-galactosaminidase secreted by were enriched in IgAN patients. These findings suggested that α-galactosidase and α-N-acetyl-galactosaminidase secreted by might be related to the production of Gd-IgA1, indicating that enzymes originated from abnormal intestinal microbiota may contribute to the production of Gd-IgA1 and play an important role in the pathogenesis of IgAN.
PubMed: 36090029
DOI: 10.3389/fmolb.2022.970723 -
Genome Biology Jun 2021The human microbiome plays an important role in cancer. Accumulating evidence indicates that commensal microbiome-derived DNA may be represented in minute quantities in...
BACKGROUND
The human microbiome plays an important role in cancer. Accumulating evidence indicates that commensal microbiome-derived DNA may be represented in minute quantities in the cell-free DNA of human blood and could possibly be harnessed as a new cancer biomarker. However, there has been limited use of rigorous experimental controls to account for contamination, which invariably affects low-biomass microbiome studies.
RESULTS
We apply a combination of 16S-rRNA-gene sequencing and droplet digital PCR to determine if the specific detection of cell-free microbial DNA (cfmDNA) is possible in metastatic melanoma patients. Compared to matched stool and saliva samples, the absolute concentration of cfmDNA is low but significantly above the levels detected from negative controls. The microbial community of plasma is strongly influenced by laboratory and reagent contaminants introduced during the DNA extraction and sequencing processes. Through the application of an in silico decontamination strategy including the filtering of amplicon sequence variants (ASVs) with batch dependent abundances and those with a higher prevalence in negative controls, we identify known gut commensal bacteria, such as Faecalibacterium, Bacteroides and Ruminococcus, and also other uncharacterised ASVs. We analyse additional plasma samples, highlighting the potential of this framework to identify differences in cfmDNA between healthy and cancer patients.
CONCLUSIONS
Together, these observations indicate that plasma can harbour a low yet detectable level of cfmDNA. The results highlight the importance of accounting for contamination and provide an analytical decontamination framework to allow the accurate detection of cfmDNA for future biomarker studies in cancer and other diseases.
Topics: Bacteroides; Cell-Free Nucleic Acids; DNA Contamination; DNA, Bacterial; Faecalibacterium; Feces; Humans; Melanoma; Microbiota; Neoplasm Metastasis; Neoplasm Staging; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Ruminococcus; Saliva; Skin Neoplasms; Symbiosis
PubMed: 34162397
DOI: 10.1186/s13059-021-02401-3 -
Nutrients Sep 2023The occurrence of obesity and related metabolic disorders is rising, necessitating effective long-term weight management strategies. With growing interest in the...
The occurrence of obesity and related metabolic disorders is rising, necessitating effective long-term weight management strategies. With growing interest in the potential role of gut microbes due to their association with responses to different weight loss diets, understanding the mechanisms underlying the interactions between diet, gut microbiota, and weight loss remains a challenge. This study aimed to investigate the potential impact of a multiphase dietary protocol, incorporating an improved ketogenic diet (MDP-i-KD), on weight loss and the gut microbiota. Using metagenomic sequencing, we comprehensively analyzed the taxonomic and functional composition of the gut microbiota in 13 participants before and after a 12-week MDP-i-KD intervention. The results revealed a significant reduction in BMI (9.2% weight loss) among obese participants following the MDP-i-KD intervention. Machine learning analysis identified seven key microbial species highly correlated with MDP-i-KD, with exhibiting the highest response. Additionally, the co-occurrence network of the gut microbiota in post-weight-loss participants demonstrated a healthier state. Notably, metabolic pathways related to nucleotide biosynthesis, aromatic amino acid synthesis, and starch degradation were enriched in pre-intervention participants and positively correlated with BMI. Furthermore, species associated with obesity, such as and , played pivotal roles in regulating these metabolic activities. In conclusion, the MDP-i-KD intervention may assist in weight management by modulating the composition and metabolic functions of the gut microbiota. , and could be key targets for gut microbiota-based obesity interventions.
Topics: Humans; Gastrointestinal Microbiome; Diet, Ketogenic; Obesity; Diet, Reducing; Ketone Bodies; Weight Loss
PubMed: 37836447
DOI: 10.3390/nu15194163 -
ImmunoHorizons Mar 2023Epithelium-derived antimicrobial peptides represent an evolutionarily ancient defense mechanism against pathogens. Regenerating islet-derived protein 3 γ (Reg3γ), the...
Epithelium-derived antimicrobial peptides represent an evolutionarily ancient defense mechanism against pathogens. Regenerating islet-derived protein 3 γ (Reg3γ), the archetypal intestinal antimicrobial peptide, is critical for maintaining host-microbe interactions. Expression of Reg3γ is known to be regulated by the microbiota through two different pathways, although it remains unknown whether specific Reg3γ-inducing bacteria act via one or both of these pathways. In recent work, we identified Ruminococcus gnavus and Limosilactobacillus reuteri as commensal bacteria able to induce Reg3g expression. In this study, we show these bacteria require myeloid differentiation primary response protein 88 and group 3 innate lymphoid cells for induction of Reg3γ in mice. Interestingly, we find that R. gnavus and L. reuteri suppress Reg3γ in the absence of either myeloid differentiation primary response protein 88 or group 3 innate lymphoid cells. In addition, we demonstrate that colonization by these bacteria is not required for induction of Reg3γ, which occurs several days after transient exposure to the organisms. Taken together, our findings highlight the complex mechanisms underlying microbial regulation of Reg3γ.
Topics: Animals; Mice; Bacteria; Immunity, Innate; Limosilactobacillus reuteri; Lymphocytes; Proteins; Ruminococcus
PubMed: 36943156
DOI: 10.4049/immunohorizons.2200096 -
Genes Dec 2022It is well accepted that the gut microbiota of breast-fed (BF) and formula-fed (FF) infants are significantly different. However, there is still a limited number of...
It is well accepted that the gut microbiota of breast-fed (BF) and formula-fed (FF) infants are significantly different. However, there is still a limited number of studies comparing the gut microbiota of BF and FF piglets, despite increasing numbers of FF piglets in the modern pig industry. The present study identified the differences in gut microbiota composition between BF- and FF-weaned Rongchang piglets at 30 days old, using pair-end sequencing on the Illumina HiSeq 2500 platform. The BF piglets had lower microbiota diversities than FF piglets (p < 0.05), and the community structures were well clustered as a result of each feeding pattern. Firmicutes and Bacteroidetes represented the most dominant phyla, and Ruminococcus, Prevotella, and Gemmiger were prominent genera in all piglets. Ruminococcus, Prevotella, Oscillospira, Eubacterium, Gemmiger, Dorea, and Lactobacillus populations were significantly higher, while Treponema and Coprococcus were significantly lower in BF piglets compared to FF piglets (p < 0.05). The metabolism pathways in the BF piglets were significantly different from FF piglets, which included carbohydrate and amino acid metabolism (p < 0.05). In addition, the top 10 abundance of microbiota were more or less significantly associated with the two phenotypes (p < 0.05). Collectively, these findings provide probable explanations for the importance of BF in neonates and support a theoretical basis for feeding regimes in indigenous Chinese piglets.
Topics: Animals; Swine; Gastrointestinal Microbiome; Microbiota; Weaning; Firmicutes; Bacteroidetes
PubMed: 36672790
DOI: 10.3390/genes14010049 -
Gut Microbes 2021Human milk glycans present a unique diversity of structures that suggest different mechanisms by which they may affect the infant microbiome development. A humanized...
Human milk glycans present a unique diversity of structures that suggest different mechanisms by which they may affect the infant microbiome development. A humanized mouse model generated by infant fecal transplantation was utilized here to evaluate the impact of fucosyl-α1,3-GlcNAc (3FN), fucosyl-α1,6-GlcNAc, lacto--biose (LNB) and galacto--biose on the fecal microbiota and host-microbiota interactions. 16S rRNA amplicon sequencing showed that certain bacterial genera significantly increased ( and ) or decreased ( and ) in all disaccharide-supplemented groups. Interestingly, cluster analysis differentiates the consumption of fucosyl-oligosaccharides from galactosyl-oligosaccharides, highlighting the disappearance of genus in both fucosyl-oligosaccharides. An increment of the relative abundance of genus was only observed with 3FN. As well, LNB significantly increased the relative abundance of , whereas the absolute levels of this genus, as measured by quantitative real-time PCR, did not significantly increase. OTUs corresponding to the species and were not present in the control after the 3-week intervention, but were shared among the donor and specific disaccharide groups, indicating that their survival is dependent on disaccharide supplementation. The 3FN-feeding group showed increased levels of butyrate and acetate in the colon, and decreased levels of serum HDL-cholesterol. 3FN also down-regulated the pro-inflammatory cytokine TNF-α and up-regulated the anti-inflammatory cytokines IL-10 and IL-13, and the Toll-like receptor 2 in the large intestine tissue. The present study revealed that the four disaccharides show efficacy in producing beneficial compositional shifts of the gut microbiota and in addition, the 3FN demonstrated physiological and immunomodulatory roles.
Topics: Acetates; Adult; Animals; Bacteria; Butyrates; DNA, Bacterial; Disaccharides; Feces; Female; Gastrointestinal Microbiome; Humans; Infant; Infant, Newborn; Male; Mice; Mice, Inbred C57BL; Milk, Human; RNA, Ribosomal, 16S; Young Adult
PubMed: 33938391
DOI: 10.1080/19490976.2021.1914377 -
Journal of Dairy Science Jun 2001We divided the adhesion process of the predominant cellulolytic rumen bacteria Fibrobacter succinogenes, Ruminococcus flavefaciens, and Ruminococcus albus into four... (Review)
Review
We divided the adhesion process of the predominant cellulolytic rumen bacteria Fibrobacter succinogenes, Ruminococcus flavefaciens, and Ruminococcus albus into four phases: 1) transport of the nonmotile bacteria to the substrate; 2) initial nonspecific adhesion of bacteria to unprotected sites of the substrate that is dominated by constitutive elements of bacterial glycocalyx; 3) specific adhesion via adhesins or ligands formation with the substrate, which can be dominated by several bacterial organelles including cellulosome complexes, fimbriae connections, glycosylated epitopes of cellulose-binding protein (CBP) or glycocalyx, and cellulose-binding domain (CBD) of enzymes; 4) proliferation of the attached bacteria on potentially digestible tissues of the substrate. Each of the phases and its significance in the adhesion process are described. Factors affecting bacterial adhesion are described including: 1) factors related to bacterial age, glycocalyx condition, and microbial competition; 2) factors related to the nature of substrate including, cuticle protection, surface area, hydration, and ionic charge; and 3) environmental factors including pH, temperature, and presence of cations and soluble carbohydrate. Based on the information available from the literature, it appears that each of the predominant rumen bacteria--F. succinogenes, R. flavefaciens, and R. albus--has a specific mechanism of adhesion to cellulose. In F. succinogenes, both the glycosidic residues of the outer membrane CBP and especially of the 180-kDa CBP, and the distinct CBD of EG2 EGF and Cl-stimulated cellobiosidase, may play a role in the adhesion to cellulose. No direct evidence, except scanning electron microscopy observations, yet supports the existence of either cellulosome complex or fimbriae structures involved in the adhesion mechanism of F. succinogenes. At least two mechanisms, cellulosome-like complexes and carbohydrate epitopes of the glycocalyx layer are involved in the specific adhesion of R. flavefaciens to cellulose. Ruminococcus albus possesses at least two mechanisms for specific adhesion to cellulose: a cellulosomal-like mechanism, and a CbpC (Pil)-protein mechanism that probably involves the production of fimbrial-like structures. Indirect and direct studies suggested that carbohydrate epitopes of CBPs and CBD epitope of cellulases may also be involved mostly in the nonspecific phase of adhesion of R. albus.
Topics: Adhesins, Bacterial; Animals; Bacteria; Bacterial Adhesion; Cattle; Cellulose; Methylcellulose; Microscopy, Electron, Scanning; Rumen; Substrate Specificity
PubMed: 11417686
DOI: 10.3168/jds.S0022-0302(01)70159-2