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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 -
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 -
Frontiers in Endocrinology 2023The risk of developing micro- and macrovascular complications is higher for individuals with type 1 diabetes (T1D). Numerous studies have indicated variations in gut...
OBJECTIVE
The risk of developing micro- and macrovascular complications is higher for individuals with type 1 diabetes (T1D). Numerous studies have indicated variations in gut microbial composition between healthy individuals and those with T1D. These changes in the gut ecosystem may lead to inflammation, modifications in intestinal permeability, and alterations in metabolites. Such effects can collectively impact the metabolic regulation system, thereby influencing blood glucose control. This review aims to explore the relationship between the gut microbiome, inflammation, and blood glucose parameters in patients with T1D.
METHODS
Google Scholar, PubMed, and Web of Science were systematically searched from 2003 to 2023 using the following keywords: "gut microbiota," "gut microbiome," "bacteria," "T1D," "type 1 diabetes," "autoimmune diabetes," "glycemic control," "glucose control," "HbA1c," "inflammation," "inflammatory," and "cytokine." The examination has shown 18,680 articles with relevant keywords. After the exclusion of irrelevant articles, seven observational papers showed a distinct gut microbial signature in T1D patients.
RESULTS
This review shows that, in T1D patients, HbA1c level was negatively correlated with abundance of , , and and positively correlated with abundance of , , , and . Instead, was negatively correlated with fasting blood glucose. In addition, there was a positive correlation between and time in range. Furthermore, a positive correlation between inflammatory parameters and gut dysbiosis was revealed in T1D patients.
CONCLUSION
We draw the conclusion that the gut microbiome profiles of T1D patients and healthy controls differ. Patients with T1D may experience leaky gut, bacterial translocation, inflammation, and poor glucose management due to microbiome dysbiosis. Direct manipulation of the gut microbiome in humans and its effects on gut permeability and glycemic control, however, have not been thoroughly investigated. Future research should therefore thoroughly examine other potential pathophysiological mechanisms in larger studies.
Topics: Humans; Blood Glucose; Diabetes Mellitus, Type 1; Dysbiosis; Gastrointestinal Microbiome; Glycated Hemoglobin; Glycemic Control; Inflammation
PubMed: 38034007
DOI: 10.3389/fendo.2023.1265696 -
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