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Frontiers in Psychiatry 2019Recently discovered relationships between the gastrointestinal microbiome and the brain have implications for psychiatric disorders, including major depressive disorder...
Recently discovered relationships between the gastrointestinal microbiome and the brain have implications for psychiatric disorders, including major depressive disorder (MDD). Bacterial transplantation from MDD patients to rodents produces depression-like behaviors. In humans, case-control studies have examined the gut microbiome in healthy and affected individuals. We systematically reviewed existing studies comparing gut microbial composition in MDD and healthy volunteers. A PubMed literature search combined the terms "depression," "depressive disorder," "stool," "fecal," "gut," and "microbiome" to identify human case-control studies that investigated relationships between MDD and microbiota quantified from stool. We evaluated the resulting studies, focusing on bacterial taxa that were different between MDD and healthy controls. Six eligible studies were found in which 50 taxa exhibited differences ( < 0.05) between patients with MDD and controls. Patient characteristics and methodologies varied widely between studies. Five phyla-, and -were represented; however, divergent results occurred across studies for all phyla. The largest number of differentiating taxa were within phylum , in which nine families and 12 genera differentiated the diagnostic groups. The majority of these families and genera were found to be statistically different between the two groups in two identified studies. Family differentiated the diagnostic groups in four studies (with an even split in directionality). Across all five phyla, nine genera were higher in MDD (, and ), six were lower (, and ), and six were divergent (, and ). We highlight mechanisms and products of bacterial metabolism as they may relate to the etiology of depression. No consensus has emerged from existing human studies of depression and gut microbiome concerning which bacterial taxa are most relevant to depression. This may in part be due to differences in study design. Given that bacterial functions are conserved across taxonomic groups, we propose that studying microbial functioning may be more productive than a purely taxonomic approach to understanding the gut microbiome in depression.
PubMed: 30804820
DOI: 10.3389/fpsyt.2019.00034 -
Frontiers in Psychiatry 2020Cumulative evidence shows a linkage between gut microbiota pattern and depression through the brain-gut microbiome axis. The aim of this systematic review was to...
Cumulative evidence shows a linkage between gut microbiota pattern and depression through the brain-gut microbiome axis. The aim of this systematic review was to identify the alterations of the gut microbiota patterns in people with depression compared to healthy controls. A comprehensive literature search of human studies, published between January 2000 and June 2019, was reviewed. The key words included gastrointestinal microbiome, gut microbiome, microbiota, depression, depressive symptoms, and depressive disorder. The systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Nine articles met the eligibility criteria. Disparities in α-diversity and β-diversity of the microbiota existed in people with depression compared to healthy controls. At the phylum level, there were inconsistencies in the abundance of , , . However, high abundance in and phyla were observed in people with depression. On the family level, high abundance of , , , , , , , , , , , , , low abundance of , , , , , , and were observed in people with depression. On the genus level, high abundance of , , , , , , , , , , , , , , , , , , , , , , , and low abundance of , , , , , , , and were found in people with depression. Alteration of gut microbiome patterns was evident in people with depression. Further evidence is warranted to allow for the translation of microbiome findings toward innovative clinical strategies that may improve treatment outcomes in people with depression.
PubMed: 32587537
DOI: 10.3389/fpsyt.2020.00541 -
Current Nutrition Reports Sep 2022Cancers are a leading cause of death in humans and for many other species. Diet has often been associated with cancers, and the microbiome is an essential mediator... (Review)
Review
PURPOSE OF REVIEW
Cancers are a leading cause of death in humans and for many other species. Diet has often been associated with cancers, and the microbiome is an essential mediator between diet and cancers. Here, we review the work on cancer and the microbiome across species to search for broad patterns of susceptibility associated with different microbial species.
RECENT FINDINGS
Some microbes, such as Helicobacter bacteria, papillomaviruses, and the carnivore-associated Fusobacteria, consistently induce tumorigenesis in humans and other species. Other microbes, such as the milk-associated Lactobacillus, consistently inhibit tumorigenesis in humans and other species. We systematically reviewed over a thousand published articles and identified links between diet, microbes, and cancers in several species of mammals, birds, and flies. Future work should examine a larger variety of host species to discover new model organisms for human preclinical trials, to better understand the observed variance in cancer prevalence across species, and to discover which microbes and diets are associated with cancers across species. Ultimately, this could help identify microbial and dietary interventions to diagnose, prevent, and treat cancers in humans as well as other animals.
Topics: Animals; Carcinogenesis; Diet; Humans; Mammals; Microbiota; Neoplasms
PubMed: 35704266
DOI: 10.1007/s13668-022-00420-5 -
Cancers Jun 2021Gut microbiota plays an important role in human health. It may promote carcinogenesis and is related to several diseases of the gastrointestinal tract. This study of... (Review)
Review
Gut microbiota plays an important role in human health. It may promote carcinogenesis and is related to several diseases of the gastrointestinal tract. This study of microbial dysbiosis in the etiology of colorectal adenoma aimed to investigate the possible causative role of microbiota in the adenoma-carcinoma sequence and its possible preventive role. A systematic, PRISMA-guided review was performed. The PubMed database was searched using "adenoma microbiota" and selecting original articles between January 2010 and May 2020 independently screened. A higher prevalence of Proteobacteria, Fusobacteria, and Bacteroidetes phyla was observed in the fecal luminal and mucosa-associated microbiota of patients with adenoma. However, other studies provided evidence of depletion of , , and . Results on the relationship between adenoma endoscopic resection and microbiota were inconsistent. In conclusion, none of the analyzed studies developed a predictive model that could differentiate adenoma from non-adenoma patients, and therefore, to prevent cancer progression. The impact of adenoma's endoscopic resection on microbiota was investigated, but the results were inconclusive. Further research in the field is required.
PubMed: 34205378
DOI: 10.3390/cancers13123061 -
Frontiers in Cellular and Infection... 2022Recent data indicate the importance of gut-kidney axis in the pathogenesis of Immunoglobulin A nephropathy (IgAN). Growing evidence suggests the alterations of diversity... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Recent data indicate the importance of gut-kidney axis in the pathogenesis of Immunoglobulin A nephropathy (IgAN). Growing evidence suggests the alterations of diversity and composition of gut microbiome among patients with IgAN, however, the details are not yet fully understood.
METHODS
Eligible studies comparing the gut microbiome between patients with IgAN and non-IgAN individuals were systematically searched from PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, and . The primary outcomes were alpha- and beta-diversity, and the differences in gut microbiota composition between patients with IgAN and non-IgAN persons. Qualitative analysis and meta-analysis were performed according to available data.
RESULTS
Eleven cross-sectional studies, including 409 patients with IgAN and 243 healthy controls, were enrolled. No significant differences in the diversity and enrichment of gut bacteria were found between IgAN and healthy individuals, whereas the beta-diversity consistently showed significant microbial dissimilarities among the two groups. , and were the dominant phyla, however, no significant differences were found between IgAN patients and healthy controls at the phylum level. The genera, and showed a higher proportion in patients with IgAN compared to healthy individuals, whereas showed a lower abundance according to meta-analysis. Qualitative analyses suggested that might be increased in IgAN patients; the genera, ,and , members of and families, were likely to have decreased abundances in patients with IgAN compared to healthy individuals.
CONCLUSION
Gut microbiota dysbiosis was demonstrated in IgAN, which might be involved in the pathogenesis of IgAN. Further studies are needed to confirm the findings of this study, due to the substantial heterogeneity.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier PROSPERO (CRD42022304034).
Topics: Bacteroidetes; Clostridiales; Cross-Sectional Studies; Dysbiosis; Gastrointestinal Microbiome; Glomerulonephritis, IGA; Humans; Verrucomicrobia
PubMed: 35656030
DOI: 10.3389/fcimb.2022.904401 -
Heliyon Feb 2023The aim of this study was to summarize previously published data and assess the alterations in the composition of the oral microbiome in OSCC using a systematic review... (Review)
Review
OBJECTIVE
The aim of this study was to summarize previously published data and assess the alterations in the composition of the oral microbiome in OSCC using a systematic review and meta-analysis.
DESIGN
Electronic databases were systematically searched for studies on the oral microbiome in OSCC published before December 2021. Qualitative assessments of compositional variations at the phylum level were performed. The meta-analysis on abundance changes of bacteria genera was performed via a random-effects model.
RESULTS
A total of 18 studies involving 1056 participants were included. They consisted of two categories of studies: 1) case-control studies (n = 9); 2) nine studies that compared the oral microbiome between cancerous tissues and paired paracancerous tissues. At the phylum level, enrichment of Fusobacteria but depletion in Actinobacteria and Firmicutes in the oral microbiome was demonstrated in both categories of studies. At the genus level, showed an increased abundance in OSCC patients (SMD = 0.65, 95% CI: 0.43-0.87, Z = 5.809, = 0.000) and in cancerous tissues (SMD = 0.54, 95% CI: 0.36-0.72, Z = 5.785, = 0.000). The abundance of was decreased in OSCC (SMD = -0.46, 95% CI: -0.88-0.04, Z = -2.146, = 0.032) and in cancerous tissues (SMD = -0.45, 95% CI: -0.78-0.13, Z = -2.726, = 0.006).
CONCLUSIONS
Disturbances in the interactions between enriched and depleted may participate in or prompt the occurrence and development of OSCC and could be potential biomarkers for detection of OSCC.
PubMed: 36793959
DOI: 10.1016/j.heliyon.2023.e13198 -
BMJ Open Jun 2021The main objective of this review was to describe and quantify the association between (FN) and acute sore throat in primary healthcare (PHC). (Meta-Analysis)
Meta-Analysis
PURPOSE
The main objective of this review was to describe and quantify the association between (FN) and acute sore throat in primary healthcare (PHC).
METHODS
In this systematic review and meta-analysis, we searched Scopus and PubMed for case-control studies reporting the prevalence of FN in patients attending primary care for an uncomplicated acute sore throat as well as in healthy controls. Only studies published in English were considered. Publications were not included if they were case studies, or if they included patients prescribed antibiotics before the throat swab, patients with a concurrent malignant disease, on immunosuppression, having an HIV infection, or patients having another acute infection in addition to a sore throat. Inclusion criteria and methods were specified in advance and published in PROSPERO. The primary outcome was positive etiologic predictive value (P-EPV), quantifying the probability for an association between acute sore throat and findings of FN in the pharynx. For comparison, our secondary outcome was the corresponding P-EPV for group A (GAS).
RESULTS
PubMed and Scopus yielded 258 and 232 studies, respectively. Removing duplicates and screening the abstracts resulted in 53 studies subsequently read in full text. For the four studies of medium to high quality included in the meta-analysis, the cumulative P-EPV regarding FN was 64% (95% CI 33% to 83%). GAS, based on data from the same publications and patients, yielded a positive EPV of 93% (95% CI 83% to 99%).
CONCLUSIONS
The results indicate that FN may play a role in PHC patients with an acute sore throat, but the association is much weaker compared with GAS.
Topics: Anti-Bacterial Agents; Fusobacterium necrophorum; HIV Infections; Humans; Pharyngitis; Primary Health Care; Streptococcus pyogenes
PubMed: 34088705
DOI: 10.1136/bmjopen-2020-042816 -
Archives of Oral Biology Sep 2021To review published oral microbiome studies and create a comprehensive list of bacterial species found in saliva and dental plaque among healthy children and adults... (Review)
Review
OBJECTIVE
To review published oral microbiome studies and create a comprehensive list of bacterial species found in saliva and dental plaque among healthy children and adults associated with presence of carious lesions and caries-free state (oral health).
DESIGN
This review followed PRISMA-ScR guidelines. We searched published studies querying PUBMED and EMBASE using the following keywords: (plaque OR saliva) AND caries AND (next generation sequencing OR checkerboard OR 16s rRNA or qPCR). Studies were limited to human studies published in English between January 1, 2010 and June 24, 2020 that included > 10 caries-active and > 10 caries-free participants, and assessed the entire bacterial community.
RESULTS
Our search strategy identified 298 articles. After exclusion criteria, 22 articles remained; we considered 2 studies that examined saliva and plaque as separate studies, for a total of 24 studies. Species associated with caries or oral health varied widely among studies reviewed, with notable differences by age and biologic sample type. No bacterial species was associated with caries in all studies. Streptococcus mutans was found more frequently among those with caries (14/24 (58.3 %)) and Fusobacterium periodonticum was found more frequently among those that were caries-free (5/24 (20.8 %)).
CONCLUSION
No bacterial species was associated with caries or oral health across all studies supporting multiple pathways to cariogenesis. However, the variation may be due to sampling at different time points during caries development, varying methods of specimen sampling, storage, sequencing or analysis or differences in host factors such as age.
Topics: Adult; Child; Dental Caries; Fusobacterium; Humans; Mouth; Oral Health; RNA, Ribosomal, 16S; Saliva; Streptococcus mutans
PubMed: 34246103
DOI: 10.1016/j.archoralbio.2021.105204 -
Archives of Oral Biology Apr 2021The aim of this study was to systematically review the literature on prevalence of microorganisms and their viability/activity in endodontic periapical lesions. (Meta-Analysis)
Meta-Analysis Review
AIMS
The aim of this study was to systematically review the literature on prevalence of microorganisms and their viability/activity in endodontic periapical lesions.
DESIGN
Literature research was performed on five electronic biomedical databases from their start dates to June 2020. Only studies evaluating the presence of microorganisms in periapical lesions in human permanent teeth with secondary/persistent infection were included. Two reviewers independently assessed the eligibility for inclusion, extracted data and evaluated the risk of bias. Meta-analysis and binominal tests were used to analyse the resulting data.
RESULTS
From the 1,313 records found, 23 full-texts were included for qualitative and quantitative analysis. The prevalence of microorganisms in endodontic periapical lesions was 87 % (95 % CI, 75-94) and the prevalence of viable/active microorganisms was 82 % (95 % CI, 66-91). There were statistical differences in the geographic area subgroup and between viable bacteria and active viruses. The most common detection method of microorganisms was the molecular one (69 %), and the most prevalent bacteria were the species Actinomyces, Fusobacterium and Prevotella (40 %). Most of the included studies had moderate risk of bias.
CONCLUSIONS
The prevalence of microorganisms in endodontic periapical lesions was 87 % and the prevalence of viable/active microorganisms was 82 %.
Topics: Fusobacterium; Humans; Prevalence; Root Canal Therapy
PubMed: 33588190
DOI: 10.1016/j.archoralbio.2021.105055 -
Archives of Oral Biology Apr 2020This systematic review aimed to analyse: a) the presence and the abundance of Fusobacterium; b) the Fusobacterium species most often found, and c) the most common... (Meta-Analysis)
Meta-Analysis
AIMS
This systematic review aimed to analyse: a) the presence and the abundance of Fusobacterium; b) the Fusobacterium species most often found, and c) the most common methods used for their identification in oral/head and neck cancer samples.
DESIGN
A protocol was registered on PROSPERO database. This review was conducted following PRISMA guidelines. Literature search was performed on five electronic biomedical databases, namely Pubmed, Scopus, Web of Science, Embase, and Cochrane from their start dates to 30 August 2018. Two reviewers independently assessed the eligibility for inclusion; extracted the data; and evaluated the risk of bias.
RESULTS
From 118 unique abstract records, 88 full-text articles were assessed for eligibility. According to inclusion and exclusion criteria, 17 publications were included in this review. Meta-analysis showed an increased prevalence of 6 % (95 % CI, 3-9) of Fusobacterium in tumour lesions than in non-tumour lesions (Fusobacterium prevalence of 16 % in tumour lesions and of 10 % in non-tumour lesions), and a 2.93 higher chance of Fusobacterium being present in tumour lesions (95 % CI, 1.47-5.81). The most common detection methods were based on molecular evidence (64.70 %) (95 % CI, 37.7-84.7). F. nucleatum was the most prevalent species (47.06 %) (95 % CI, 23.5-72).
CONCLUSION
In conclusion, Fusobacterium is present and in higher abundance in oral/head and neck cancer samples when compared to non-cancer samples, suggesting that Fusobacterium may contribute to oral/head and neck cancer development.
Topics: Fusobacterium; Head and Neck Neoplasms; Humans
PubMed: 32028171
DOI: 10.1016/j.archoralbio.2020.104669