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Microbial Pathogenesis Jul 2024Recent research has revealed that alterations of the gut microbiome (GM) play a comprehensive role in the pathophysiology of HF. However, findings in this field remain... (Meta-Analysis)
Meta-Analysis Review
Recent research has revealed that alterations of the gut microbiome (GM) play a comprehensive role in the pathophysiology of HF. However, findings in this field remain controversial. In this study, we focus on differences in GM diversity and abundance between HF patients and non-HF people, based on previous 16 S ribosomal RNA (16rRNA) gene sequencing. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a comprehensive search of PubMed, Web of Science, Embase, Cochrane Library, and Ovid databases using the keyword "Heart failure" and "Gastrointestinal Microbiome". A significant decrease in alpha diversity was observed in the HF patients (Chao1, I = 87.5 %, p < 0.001; Shannon index, I = 62.8 %, p = 0.021). At the phylum level, the HF group exhibited higher abundances of Proteobacteria (I = 92.0 %, p = 0.004) and Actinobacteria (I = 82.5 %, p = 0.010), while Bacteroidetes (I = 45.1 %, p = 0.017) and F/B ratio (I = 0.0 %, p<0.001) were lower. The Firmicutes showed a decreasing trend but did not reach statistical significance (I = 82.3 %, p = 0.127). At the genus level, the relative abundances of Streptococcus, Bacteroides, Alistipes, Bifidobacterium, Escherichia-Shigella, Enterococcus and Klebsiella were increased in the HF group, whereas Ruminococcus, Faecalibacterium, Dorea and Megamona exhibited decreased relative abundances. Dialister, Blautia and Prevotella showed decreasing trends but without statistical significance. This observational meta-analysis suggests that GM changes are associated with HF, manifesting as alterations in GM abundance, disruptions in the production of short-chain fatty acids (SCFAs) bacteria, and an increase in trimethylamine N-oxide (TMAO) producing bacteria.
Topics: Gastrointestinal Microbiome; Humans; Heart Failure; Bacteria; RNA, Ribosomal, 16S; Proteobacteria; Bacteroidetes
PubMed: 38788811
DOI: 10.1016/j.micpath.2024.106647 -
Avian Pathology : Journal of the W.V.P.A May 2024Probiotics can enhance broiler chicken health by improving intestinal microbiota, potentially replacing antibiotics. They protect against bacterial diseases like... (Review)
Review
Probiotics can enhance broiler chicken health by improving intestinal microbiota, potentially replacing antibiotics. They protect against bacterial diseases like Necrotic enteritis (NE) in poultry. Understanding their role is crucial for managing bacterial diseases, including NE. This study conducted a meta-analysis to assess the effects of probiotic supplementation on Feed conversion ratio (FCR), NE lesion score, and mortality. Additionally, a systematic review analyzed gut microbiota changes in broilers challenged with with or without the probiotic supplementation. Effect sizes from the studies were estimated in terms of standardized mean difference (SMD). Random effect models were fit to estimate the pooled effect size and 95% confidence interval (CI) of the pooled effect size between the control [probiotic-free + ] and the treatment group [ supplemented + ]. Overall variance is computed by heterogeneity (Q). The meta-analysis showed that probiotic supplementation significantly improved FCR and reduced NE lesion score but had no effect on mortality rates. The estimated overall effects of probiotic supplementation on FCR, NE lesion score and mortality percentage in term of SMD were -0.91 (CI = -1.34, -0.49; p < 0.001*); -0.67 (CI = -1.11, -0.22; p = 0.006*), and -0.32 (CI = -0.70, 0.06; p = 0.08), respectively. Heterogeneity analysis indicated significant variations across studies for FCR (Q = 69.66; p < 0.001*) and NE lesion score (Q = 42.35; p < 0.001*) while heterogeneity was not significant for mortality (Q = 2.72; p = 0.74). probiotic supplementation enriched specific gut microbiota including . These microbiotas were found to upregulate expression of various genes such as TJ proteins occluding, ZO-1, junctional adhesion 2 (JAM2), interferon gamma, IL12- β and transform growth factor-β4. Moreover, downregulated mucin-2 expression was involved in restoring intestinal physical barrier, reducing intestinal inflammation, and recovering the physiological functions of damaged intestines. These findings highlight the potential benefits of probiotic supplementation in poultry management, particularly in combating bacterial diseases and promoting intestinal health.
PubMed: 38776185
DOI: 10.1080/03079457.2024.2359596 -
Clinical and Experimental... 2024The diagnosis of irritable bowel syndrome (IBS) is based on symptom-based criteria due to lack of reliable disease-specific biomarkers. Gut microbiota is perturbed in... (Review)
Review
A Systematic Review: Fecal Bacterial Profile in Patients with Irritable Bowel Syndrome Analyzed with the GA-Map Dysbiosis Test Based on the 16S rRNA Gene of Bacterial Species or Groups.
PURPOSE
The diagnosis of irritable bowel syndrome (IBS) is based on symptom-based criteria due to lack of reliable disease-specific biomarkers. Gut microbiota is perturbed in IBS and when comparing different methods used to analyze gut microbiota, the results might be obscured. Therefore, in this systematic review we aimed to investigate the profile of fecal bacterial markers and dysbiosis index (DI) in patients with IBS and IBS subgroups compared to healthy controls (HCs) conducted by the same method (GA-map Dysbiosis Test based on16S rRNA sequencing).
MATERIAL AND METHOD
We searched PubMed, EMBASE (Ovid) and Cochrane Library for case-control studies comparing fecal gut microbiota analyzed with the GA-map Dysbiosis Test (Oslo, Norway) in patients with IBS and HCs. Our outcomes were the difference in fecal bacterial markers and DI in patients with IBS and IBS subgroups compared to HCs.
RESULTS
The search identified 28 citations; five articles were included. Most studies evaluated fecal bacterial markers and DI in patients with diarrhea-predominant IBS (IBS-D). Results of fecal bacteria profile in IBS and IBS subgroups compared to HCs are inconsistent, however, two studies showed increased levels of in IBS-D compared to HCs and results of DI indicated IBS and IBS subgroups (especially IBS-D) having higher DI compared to HCs.
CONCLUSION
This systematic review revealed inconsistent findings in respect to differences in bacterial markers between IBS and IBS subgroups with HCs in studies using the GA-map Dysbiosis Test based on 16S rRNA sequencing. However, the test is quite novel, and few studies have used the method so far. More research comparing fecal microbiota profile differences in IBS and IBS subgroups compared to HCs utilizing the same method of analysis is needed to give us further insight into the gut bacteria profile in IBS and the clinical consequences of intestinal dysbiosis.
PubMed: 38646157
DOI: 10.2147/CEG.S451675 -
Diagnostic Microbiology and Infectious... Jul 2024Increasing evidence has indicated dysbiosis of the gut microbiota in patients with pulmonary tuberculosis (PTB). However, the change in the intestinal microbiota varies... (Review)
Review
Increasing evidence has indicated dysbiosis of the gut microbiota in patients with pulmonary tuberculosis (PTB). However, the change in the intestinal microbiota varies between different studies. This systematic review was conducted to investigate the characteristics of the gut microbiota in PTB patients. The MBASE, MEDLINE, Web of Science, and Cochrane Library electronic databases were systematically searched, and the quality of the retrieved studies was evaluated using the Newcastle-Ottawa scale. A total of 12 studies were finally included in the systematic review. Compared with healthy controls, the index reflecting α-diversity including the richness and/or diversity index decreased in 6 studies, while β-diversity presented significant differences in PTB patients in 10 studies. Although the specific gut microbiota alterations were inconsistent, short-chain fatty acid-producing bacteria (including Lachnospiraceae, Ruminococcus, Blautia, Dorea, and Faecalibacterium), bacteria associated with an inflammatory state (e.g., Prevotellaceae and Prevotella), and beneficial bacteria (e.g., Bifidobacteriaceae and Bifidobacterium) were commonly noted. Our systematic review identifies key evidence for gut microbiota alterations in PTB patients, in comparison with healthy controls; however, no consistent conclusion could be drawn, due to the inconsistent results and heterogeneous methodologies of the enrolled studies. Therefore, more well-designed research with standard methodologies and large sample sizes is required.
Topics: Humans; Gastrointestinal Microbiome; Tuberculosis, Pulmonary; Dysbiosis; Bacteria
PubMed: 38581928
DOI: 10.1016/j.diagmicrobio.2024.116291 -
PloS One 2024Alterations in the composition and abundance of the intestinal microbiota occur in non-alcoholic fatty liver disease (NAFLD). However, the results are inconsistent... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Alterations in the composition and abundance of the intestinal microbiota occur in non-alcoholic fatty liver disease (NAFLD). However, the results are inconsistent because of differences in the study design, subject area, and sequencing methodology. In this study, we compared the diversity and abundance of the intestinal microbiota of patients with NAFLD and healthy individuals through a systematic review and meta-analysis.
METHODS
Three databases (PubMed, EMBASE, and Cochrane Library) were searched from their inception to March 20, 2023. A meta-analysis was performed using Stata software to analyze variations in the richness and abundance of the intestinal microbiota in patients with NAFLD. The Newcastle-Ottawa Quality Assessment Scale (NOS) was used for quality assessment.
RESULTS
A total of 28 articles were included. Shannon diversity was reduced in patients with NAFLD (SMD = -0.24 (95% CI -0.43-0.05, I2 = 71.7%). The relative abundance of Ruminococcus, Faecalibacterium, and Coprococcus all decreased, with total SMDs of -0.96 (95% CI -1.29 to -0.63, I2 = 4.8%), -1.13 (95% CI -2.07 to -0.19, I2 = 80.5%), and -1.66 (95% CI -3.04 to -0.28, I2 = 91.5%). Escherichia was increased in individuals with NAFLD (SMD = 1.78, 95% CI 0.12 to 3.45, I2 = 94.4%).
CONCLUSION
Increasing the species diversity and altering the abundance of specific gut microbiota, including Coprococcus, Faecalibacterium, Ruminococcus, and Escherichia, may be beneficial for improving NAFLD.
Topics: Humans; Non-alcoholic Fatty Liver Disease; Gastrointestinal Microbiome; Gram-Positive Cocci; Faecalibacterium; Research Design; Clostridiales
PubMed: 38547205
DOI: 10.1371/journal.pone.0299946 -
Clinical & Translational Oncology :... Jun 2024Breast cancer (BC) is a devastating disease for women. Microbial influences may be involved in the development and progression of breast cancer. This study aimed to... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Breast cancer (BC) is a devastating disease for women. Microbial influences may be involved in the development and progression of breast cancer. This study aimed to investigate the difference in intestinal flora abundance between breast cancer patients and healthy controls (HC) based on previous 16S ribosomal RNA (rRNA) gene sequencing results, which have been scattered and inconsistent in previous studies.
MATERIALS AND METHODS
In agreement with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we searched for pertinent literature in Pubmed, Embase, Cochrane Library, and Web of Science databases from build until February 1, 2023. Relative abundance, diversity of intestinal microflora by level, microbial composition, community structure, diversity index, and other related data were extracted. We used a fixed or random effects model for data analysis. We also conducted funnel plot analysis, sensitivity analysis, Egger's, and Begg's tests to assess the bias risk.
RESULTS
A total of ten studies involving 734 BC patients were enrolled. It was pointed out that there were significant differences in the Chao index between BC and HC in these studies [SMD = - 175.44 (95% CI - 246.50 to - 104.39)]. The relative abundance of Prevotellaceae [SMD = - 0.27 (95% CI - 0.39 to - 0.15)] and Bacteroides [SMD = 0.36 (95% CI 0.23-0.49)] was significantly different. In the included articles, the relative abundance of Prevotellaceae, Ruminococcus, Roseburia inulinivorans, and Faecalibacterium prausnitzii decreased in BC. Accordingly, the relative richness of Erysipelotrichaceae was high in BC.
CONCLUSIONS
This observational meta-analysis revealed that the changes in gut microbiota were correlated with BC, and the changes in some primary fecal microbiota might affect the beginning of breast cancer.
Topics: Humans; Breast Neoplasms; RNA, Ribosomal, 16S; Female; Gastrointestinal Microbiome; Feces
PubMed: 38217684
DOI: 10.1007/s12094-023-03373-5 -
Reproductive Sciences (Thousand Oaks,... Jan 2024Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder that is frequently linked to anovulation in women who are experiencing infertility.... (Review)
Review
Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder that is frequently linked to anovulation in women who are experiencing infertility. Intestinal flora, also known as the "second genome" of the host, is closely associated with chronic metabolic diseases. Recently, there has been increasing attention on the connection between PCOS and the gut microbiome, and experiments have been conducted. However, the results were unsatisfactory and inconsistent. This review aims to provide a comprehensive overview of the literature investigating the associations between the gut microbiome and PCOS in adults. The goal is to identify whether there are changes in the composition of the gut microbiome in individuals with PCOS. This is the first systematic review to focus on functional alterations in the gut microbiome, which could provide insights into potential mechanisms of microbial involvement in the development of PCOS. We found that there was no significant change in gut microbiome biodiversity in PCOS. Meta-analyses of three studies revealed a significantly higher abundance of Proteobacteria (1.12, 95% CI, 0.21, 2.02, I = 0%) in adults with PCOS. At the genus level, Bacteroides, Enterococcus, and Escherichia-Shigella were found to be enriched in patients with PCOS. Species such as Ruminococcus gnavus group, Parabacteroides distasonis, and Bacteroides fragilis showed an increase in PCOS. Metabolic pathways associated with glucose, lipid metabolism, bile acid metabolism, and protein absorption were found to be enriched in individuals with PCOS. The gut microbiome in PCOS is not characterized by lower diversity, but the composition is altered at the phylum, family, genus, or species level. Consequently, the metabolic pathway differs according to the phenotype of PCOS.
PubMed: 38212581
DOI: 10.1007/s43032-023-01440-4 -
Renal Failure 2023Emerging evidence suggests that gut microbiota dysbiosis may play a critical role in the development of lupus nephritis (LN). However, the specific characteristics of... (Review)
Review
BACKGROUND
Emerging evidence suggests that gut microbiota dysbiosis may play a critical role in the development of lupus nephritis (LN). However, the specific characteristics of the gut microbiota in individuals with LN have not been fully clarified.
METHODS
The PubMed, Web of Science, and Embase databases were systematically searched for clinical and animal studies related to the relationship between LN and gut microbiota from inception until October 1, 2023. A semiquantitative analysis was used to assess the changes in gut microbial profiles.
RESULTS
A total of 15 clinical studies were selected for analysis, which included 138 LN patients, 441 systemic lupus erythematosus patients, and 1526 healthy controls (HCs). Five different types of LN mouse models were included in 5 animal studies. The alpha diversity was decreased in LN patients compared to HCs. A significant decrease in the (F/B) ratio is considered a hallmark of pathological conditions. Specifically, alterations in the abundance of the phylum , genera and and species and may play a critical role in the pathogenesis of LN. Remarkably, the gut taxonomic chain -- was enriched in LN patients, which could be a crucial characteristic of LN patients. The increased level of interleukin-6, imbalance of regulatory T cells and T helper 17 cells, and decreased level of the intestinal tight junction proteins zonula occludens-1 and claudin-1 also might be related to the pathogenesis of LN.
CONCLUSIONS
Specific changes in the abundance of gut microbiota such as decreased F/B ratio, and the level of inflammatory indicators, and markers of intestinal barrier dysfunction may play a crucial role in the pathogenesis of LN. These factors could be effective diagnostic and potential therapeutic targets for LN.
Topics: Animals; Mice; Humans; Lupus Nephritis; Gastrointestinal Microbiome; Lupus Erythematosus, Systemic; Intestinal Diseases; Interleukin-6
PubMed: 37994423
DOI: 10.1080/0886022X.2023.2285877 -
The Journal of Nutrition, Health & Aging 2023Obesity in the older adults is a health concern that increases the risk of several life-threatening diseases. Previous research has been revealed that alterations in the...
BACKGROUND
Obesity in the older adults is a health concern that increases the risk of several life-threatening diseases. Previous research has been revealed that alterations in the gut microbiota composition is related to obesity. So, understanding the gut microbiota changes in older adults' obesity may help to provide promising strategies for their health management.
OBJECTIVES
Here we conducted a systematic review that investigate the alteration of gut microbiota composition in association with obesity and its indices in the older adults.
DESIGN
Systematic review.
SETTING
A comprehensive systematic search was performed through PubMed, Web of Science, Scopus and Embase databases for all relative studies up to 2023 with the main search concepts as Microbiota, Obesity and Elderly. The data about gut microbiota in association with obesity indices had been extracted.
PARTICIPANTS
Older adults (≥60 years).
INTERVENTION
None.
MEASUREMENTS
None.
RESULTS
Within 10741 recordes, 11 studies met the inclusion criteria and were included in this systematic review. Most of them indicated the gut microbiota alterations in obese compared with non-obese older adults. However, the gut microbiome composition in obese older adults is affected by other underlying diseases like diabetes and metabolic syndrome. The most important taxa that had abundance alteration in association with obesity in older adults were Christensenellaceae, Porphyromonadaceae and Rikenellaceae, Akkermansia, Blautia, Prevotella, Ruminococcus, Bacteroides and Faecalibacterium.
CONCLUSION
The gut microbiota composition is associated with obesity in older adults. Considering the other factors affecting the composition of gut microbiota, such as age, underlying diseases and lifestyle, a more accurate conclusion about this matter requires more future studies.
Topics: Humans; Aged; Gastrointestinal Microbiome; Obesity; Microbiota; Metabolic Syndrome; Diabetes Mellitus
PubMed: 37960904
DOI: 10.1007/s12603-023-1988-8 -
Journal of Gastrointestinal and Liver... Sep 2023Traditional cardiovascular risk factors are established predictors of heart failure (HF). However, the human gut microbiota is suggested to potentially interact with the...
BACKGROUND AND AIMS
Traditional cardiovascular risk factors are established predictors of heart failure (HF). However, the human gut microbiota is suggested to potentially interact with the cardiovascular system through the "gut-heart axis", which induces inflammation and contributes to HF pathogenesis. This systematic review aims to confirm the interconnection between the gut microbiome in HF patients.
METHODS
Peer-reviewed human studies comparing the gut microbiota profile in adult patients with HF and healthy controls (HCs) up to April 18, 2022, were searched in Ovid MEDLINE, Ovid EMBASE, SCOPUS, and the Cochrane Library. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS).
RESULTS
A total of nine studies, including 317 HF patients and 510 HCs, were included in the review. Decreased gut microbiota richness and similar microbial diversity (alpha diversity), and significantly different gut microbiota composition (beta diversity) were observed between HF patients and HCs. In comparison to HCs, HF patients had a greater abundance of Actinobacteria, Proteobacteria, and Synergistetes phyla; Enterococcus, Escherichia, Klebsiella, Lactobacillus, Streptococcus, and Veilonella genera and Ruminococcus gnavus, Streptococcus sp., and Veilonella sp. species. In contrast, there was decreased abundance of Firmicutes phylum; Blautia, Eubacterium, Faecalibacterium, and Lachnospiraceae FCS020 genera; and Dorea longicatena, Eubacterium rectale, Faecalibacterium prausnitzii, Oscillibacter sp., and Sutterella wadsworthensis species in HF patients.
CONCLUSIONS
Gut microbiota diversity, richness, and composition in HF patients differ significantly from the healthy population. Overall, short-chain fatty acid (SCFA)-producing gut microbiota was depleted in HF patients. However, different underlying comorbidities, environments, lifestyles, and dietary choices could affect gut microbiota heterogeneity.
Topics: Adult; Humans; Gastrointestinal Microbiome; Diet; Bacteria; Heart Failure; Inflammation
PubMed: 37774217
DOI: 10.15403/jgld-4779