-
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 -
BMC Cancer Feb 2024Increasing evidence indicates that gut microbiota are closely related to prostate cancer. This study aims to assess the gut microbiota composition in patients with... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Increasing evidence indicates that gut microbiota are closely related to prostate cancer. This study aims to assess the gut microbiota composition in patients with prostate cancer compared to healthy participants, thereby advancing understanding of gut microbiota's role in prostate cancer.
METHODS
A systematic search was conducted across PubMed, Web of Science, and Embase databases, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The methodological quality of included studies was evaluated using the Newcastle-Ottawa Scale (NOS), and pertinent data were analyzed. The kappa score assessed interrater agreement.
RESULTS
This study encompassed seven research papers, involving 250 prostate cancer patients and 192 controls. The kappa was 0.93. Meta-analysis results showed that alpha-diversity of gut microbiota in prostate cancer patients was significantly lower than in the control group. In terms of gut microbiota abundance, the ratio of Proteobacteria, Bacteroidia, Clostridia, Bacteroidales, Clostridiales, Prevotellaceae, Lachnospiraceae, Prevotella, Escherichia-Shigella, Faecalibacterium, and Bacteroides was higher in prostate cancer patients. Conversely, the abundance ratio of Actinobacteria, Bacteroidetes, Firmicutes, Selenomonadales, Veillonella, and Megasphaera was higher in the control group.
CONCLUSION
Our study reveals differences in alpha-diversity and abundance of gut microbiota between patients with prostate cancer and controls, indicating gut microbiota dysbiosis in those with prostate cancer. However, given the limited quality and quantity of selected studies, further research is necessary to validate these findings.
Topics: Male; Humans; Gastrointestinal Microbiome; Bacteria; Dysbiosis; Prostatic Neoplasms
PubMed: 38402385
DOI: 10.1186/s12885-024-12018-x -
Journal of Neurology Mar 2024The gut microbiome may play a role in multiple sclerosis (MS). However, its relationship with the disease-modifying therapies (DMTs) remains unclear. We systematically...
BACKGROUND
The gut microbiome may play a role in multiple sclerosis (MS). However, its relationship with the disease-modifying therapies (DMTs) remains unclear. We systematically reviewed the literature to examine the relationship between DMTs and the gut microbiota among persons with MS (pwMS).
METHODS
MEDLINE, EMBASE, Web of Science, and Scopus were searched (01/2007-09/2022) for studies evaluating potential gut microbiota differences in diversity, taxonomic relative abundances, and functional capacity between DMT-exposed/unexposed pwMS or before/after DMT initiation. All US FDA-approved MS DMTs (1993-09/2022) and rituximab were included.
RESULTS
Of the 410 studies, 11 were included, totalling 1243 pwMS. Of these, 821 were DMT exposed and 473 unexposed, including 51 assessed before/after DMT initiation. DMT use duration ranged from 14 days to > 6 months. No study found a difference in gut microbiota alpha-diversity between DMT exposed/unexposed (p > 0.05). One study observed a difference in beta-diversity between interferon-beta users/DMT non-users (weighted UniFrac, p = 0.006). All studies examined taxa-level differences, but most (6) combined different DMTs. Two or more studies reported eight genera (Actinomyces, Bacteroides, Clostridium sensu stricto 1, Haemophilus, Megasphaera, Pseudomonas, Ruminiclostridium 5, Turicibacter) and one species (Ruthenibacterium lactatiformans) differing in the same direction between DMT exposed/unexposed. DMT users had lower relative abundances of carbohydrate degradation and reductive tricarboxylic acid cycle I pathway than non-users (p < 0.05), but findings could not be attributed to a specific DMT.
DISCUSSION
While DMT use (versus no use) was not associated with gut microbiota diversity differences, taxa-level differences were observed. Further work is warranted, as most studies were cross-sectional, few examined functionality, and DMTs were combined.
Topics: Humans; Multiple Sclerosis; Gastrointestinal Microbiome; Interferon-beta; Rituximab
PubMed: 38078977
DOI: 10.1007/s00415-023-12107-0