Браузер не даёт сохранять данные (например, приватный режим): закладки пропадут после закрытия вкладки.
Поиск статей PubMed
Ключевые слова, автор, журнал, годы — результаты из PubMed, аннотации с переводом на русский, закладки в браузере.
Найдено: 3 219
Страница 310 из 322-
Probiotic treatment causes sex-specific neuroprotection after traumatic brain injury in mice.
BACKGROUND: Recent studies have shed light on the potential role of gut dysbiosis in shaping traumatic brain injury (TBI) outcomes. Changes in the levels and types of Lactobacillus bacteria present might impact the immune system disturbances, neuroinflammatory responses, anxiety and depressive-like behaviors, and compromised neuroprotection mechanisms triggered by TBI. OBJECTIVE: This study aimed to investigate the effects of a daily pan-probiotic (PP) mixture in drinking water containing strains of Lactobacillus plantarum, L. reuteri, L. helveticus, L. fermentum, L. rhamnosus, L. gasseri, and L. casei, administered for either two or seven weeks before inducing TBI on both male and female mice. METHODS: Mice were subjected to controlled cortical impact (CCI) injury. Short-chain fatty acids (SCFAs) analysis was performed for metabolite measurements. The taxonomic profiles of murine fecal samples were evaluated using 16S rRNA V1-V3 sequencing analysis. Histological analyses were used to assess neuroinflammation and gut changes post-TBI, while behavioral tests were conducted to evaluate sensorimotor and cognitive functions. RESULTS: Our findings suggest that PP administration modulates the diversity and composition of the microbiome and increases the levels of SCFAs in a sex-dependent manner. We also observed a reduction of lesion volume, cell death, and microglial and macrophage activation after PP treatment following TBI in male mice. Furthermore, PP-treated mice show motor function improvements and decreases in anxiety and depressive-like behaviors. CONCLUSION: Our findings suggest that PP administration can mitigate neuroinflammation and ameliorate motor and anxiety and depressive-like behavior deficits following TBI. These results underscore the potential of probiotic interventions as a viable therapeutic strategy to address TBI-induced impairments, emphasizing the need for gender-specific treatment approaches.
-
The impact of microbiota on brain and behavior: mechanisms & therapeutic potential.
There is increasing evidence that host-microbe interactions play a key role in maintaining homeostasis. Alterations in gut microbial composition is associated with marked changes in behaviors relevant to mood, pain and cognition, establishing the critical importance of the bi-directional pathway of communication between the microbiota and the brain in health and disease. Dysfunction of the microbiome-brain-gut axis has been implicated in stress-related disorders such as depression, anxiety and irritable bowel syndrome and neurodevelopmental disorders such as autism. Bacterial colonization of the gut is central to postnatal development and maturation of key systems that have the capacity to influence central nervous system (CNS) programming and signaling, including the immune and endocrine systems. Moreover, there is now expanding evidence for the view that enteric microbiota plays a role in early programming and later response to acute and chronic stress. This view is supported by studies in germ-free mice and in animals exposed to pathogenic bacterial infections, probiotic agents or antibiotics. Although communication between gut microbiota and the CNS are not fully elucidated, neural, hormonal, immune and metabolic pathways have been suggested. Thus, the concept of a microbiome-brain-gut axis is emerging, suggesting microbiota-modulating strategies may be a tractable therapeutic approach for developing novel treatments for CNS disorders.
-
Human Milk Microbiome and Maternal Postnatal Psychosocial Distress.
Human milk contains many bioactive components, including bacteria, which are transferred to the developing infant through breastfeeding. Milk bacteria appear to, amongst others, originate from the maternal gut. A mother's postnatal psychosocial distress may alter maternal gut microbiota, which in turn may affect the bacteria present in milk. The aim of this study was to explore whether maternal postnatal psychosocial distress was related to alterations in the relative abundances of specific bacteria and to milk microbial diversity. Healthy mothers (N = 77; N = 51 with complete data) collected breast milk samples at 2, 6, and 12 weeks postpartum and filled in mood questionnaires on experienced stress, anxiety, and depressive symptoms at 6 weeks postpartum. A metataxonomic approach (16S rRNA gene sequencing (region V3 and V4) using Illumina MiSeq technology) was used to assess bacterial abundances and diversity. For the group as a whole, an increase in diversity of the milk bacterial community was observed during the first 3 months of breastfeeding (Shannon index). This general increase in diversity appears to be explained by an increase of Lactobacillus and other minor genera, together with a decrease in Staphylococcus. With respect to psychological distress and milk microbial composition, no significant differences in the relative abundance of major bacterial genera were detected between women with high (N = 13) and low (N = 13) psychosocial distress. However, progressive and distinct changes in the content of Firmicutes, Proteobacteria, and Bacteroidetes at the phylum level and Acinetobacter, Flavobacterium, and Lactobacillus at the genera level were observed in milk samples of women with low psychosocial distress. With respect to milk microbial diversity, high maternal psychosocial distress, compared to low maternal psychosocial distress, was related to significantly lower bacterial diversity in milk at 3 months post-delivery. Anxiety, stress, and depressive symptoms separately were unrelated to specific bacterial profiles. The current study suggests a potential relation between maternal psychosocial distress and milk microbiota, providing first evidence of a possible mechanism through which post-partum psychological symptoms may affect infant development and health.
-
The Oral and Fecal Microbiota in a Canadian Cohort of Alzheimer's Disease.
BACKGROUND: Despite decades of research, our understanding of Alzheimer's disease (AD) etiology remains incomplete. In recent years, appreciation has grown for potential roles for the microbiota in shaping neurological health. OBJECTIVE: This study aimed to examine associations between the microbiota and AD in a human cross-sectional cohort. METHODS: Forty-five AD patients and 54 matched controls were recruited in Vancouver, Canada. Fecal and oral samples underwent 16S microbiota sequencing. A wide array of demographic and clinical data were collected. Differences between participant groups were assessed, and associations between microbes and clinical variables were examined within the AD population. RESULTS: The gut microbiota of AD patients displayed lower diversity relative to controls, although taxonomic differences were sparse. In contrast, the AD oral microbiota displayed higher diversity, with several taxonomic differences relative to controls, including a lower abundance of the families Streptococcaceae and Actinomycetaceae, and a higher abundance of Weeksellaceae, among others. The periodontitis-associated oral microbe Porphyromonas gingivalis was 5 times more prevalent among patients. No significant associations between gut or oral microbes and cognition were detected, but several correlations existed between microbes and mood disorders and BMI among patients, including a strong positive correlation between Alphaproteobacteria and depression score. CONCLUSION: The gut microbiota of AD patients was not overtly different from controls, although it displayed lower diversity, an overall marker of microbiota health. The oral microbiota did display marked differences. Cognition was not associated with a microbial signature, but other relevant AD factors including mood and BMI did demonstrate an association.
-
Oral Dysbiosis and Neuroinflammation: Implications for Alzheimer's, Parkinson's and Mood Disorders.
BACKGROUND: Growing evidence indicates that oral microbiome dysbiosis contributes to systemic inflammation, immune activation, and neural dysfunction. These processes may influence the onset and progression of major neuropsychiatric and neurodegenerative disorders. This review integrates clinical, epidemiological, and mechanistic findings linking periodontal pathogens and oral microbial imbalance to Alzheimer's disease (AD), Parkinson's disease (PD), depression, and anxiety. METHODS: A narrative review was conducted using PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar to identify recent studies examining alterations in the oral microbiota, microbial translocation, systemic inflammatory responses, blood-brain barrier disruption, cytokine signaling, and neural pathways implicated in brain disorders. RESULTS: Evidence from human and experimental models demonstrates that oral pathogens, particularly Porphyromonas gingivalis, Fusobacterium nucleatum, and Treponema denticola, can disseminate systemically, alter immune tone, and affect neural tissues. Their virulence factors promote microglial activation, cytokine release (IL-1β, IL-6, TNF-α), amyloid-β aggregation, and α-synuclein misfolding. Epidemiological studies show associations between oral dysbiosis and cognitive impairment, motor symptoms in PD, and alterations in mood-related taxa linked to stress hormone profiles. Immunometabolic pathways, HPA-axis activation, and the oral-gut-brain axis further integrate these findings into a shared neuroinflammatory framework. CONCLUSIONS: Oral dysbiosis emerges as a modifiable contributor to neuroinflammation and brain health. Periodontal therapy, probiotics, prebiotics, synbiotics, and targeted inhibitors of bacterial virulence factors represent promising strategies to reduce systemic and neural inflammation. Longitudinal human studies and standardized microbiome methodologies are still needed to clarify causality and evaluate whether restoring oral microbial balance can modify the course of neuropsychiatric and neurodegenerative disorders.
-
Fecal microbiome profiles of neonatal dairy calves with varying severities of gastrointestinal disease.
Gastrointestinal disease (GI) is the most common illness in pre-weaned dairy calves. Studies have associated the fecal microbiome composition with health status, but it remains unclear how the microbiome changes across different levels of GI disease and breeds. Our objective was to associate the clinical symptoms of GI disease with the fecal microbiome. Fecal samples were collected from calves (n = 167) of different breeds (Holstein, Jersey, Jersey-cross and beef-cross) from 4-21 d of age. Daily clinical evaluations assessed health status. Calves with loose or watery feces were diagnosed with diarrhea and classified as bright-sick (BS) or depressed-sick (DS) according to behavior. Calves with normal or semiformed feces and no clinical illness were classified as healthy (H). One hundred and three fecal samples were obtained from consistently healthy calves and 64 samples were from calves with diarrhea (n = 39 BS; n = 25 DS). The V3-V4 region of 16S rRNA gene was sequenced and analyzed. Differences were identified by a linear-mixed effects model with a negative binomial error. DS and Jersey calves had a higher relative abundance of Streptococcus gallolyticus relative to H Holstein calves. In addition, DS calves had a lower relative abundance of Bifidobacterium longum and an enrichment of Escherichia coli. Species of the genus Lactobacillus, such as an unclassified Lactobacillus, Lactobacillus reuteri, and Lactobacillus salivarius were enriched in calves with GI disease. Moreover, we created a model to predict GI disease based on the fecal microbiome composition. The presence of Eggerthella lenta, Bifidobacterium longum, and Collinsella aerofaciens were associated with a healthy clinical outcome. Although lactobacilli are often associated with beneficial probiotic properties, the presence of E. coli and Lactobacillus species had the highest coefficients positively associated with GI disease prediction. Our results indicate that there are differences in the fecal microbiome of calves associated with GI disease severity and breed specificities.
-
Effects of subchronic and mild social defeat stress on the intestinal microbiota and fecal bile acid composition in mice.
The gut microbiota plays a crucial role in both the pathogenesis and alleviation of host depression by modulating the brain-gut axis. We have developed a murine model of human depression called the subchronic and mild social defeat stress (sCSDS) model, which impacts not only behavior but also the host gut microbiota and gut metabolites, including bile acids. In this study, we utilized liquid chromatography/mass spectrometry (LC/MS) to explore the effects of sCSDS on the mouse fecal bile acid profile. sCSDS mice exhibited significantly elevated levels of deoxycholic acid (DCA) and lithocholic acid (LCA) in fecal extracts, leading to a notable increase in total bile acids and 7α-dehydroxylated secondary bile acids. Consequently, a noteworthy negative correlation was identified between the abundances of DCA and LCA and the social interaction score, an indicator of susceptibility in stressed mice. Furthermore, analysis of the colonic microbiome unveiled a negative correlation between the abundance of CDCA and Turicibacter. Additionally, DCA and LCA exhibited positive correlations with Oscillospiraceae and Lachnospiraceae but negative correlations with the Eubacterium coprostanoligenes group. These findings suggest that sCSDS impacts the bidirectional interaction between the gut microbiota and bile acids and is associated with reduced social interaction, a behavioral indicator of susceptibility in stressed mice.
-
Gut microbiota signatures differentiate trajectory-defined response phenotypes and predict self-management outcomes in irritable bowel syndrome.
BACKGROUND: Heterogeneity in symptom presentation and treatment response in irritable bowel syndrome (IBS) remains poorly understood. The gut microbiota may contribute to this variability, but its role in shaping symptom trajectories and responses to self-management interventions is unclear. OBJECTIVE: To identify symptom trajectory phenotypes and determine whether gut microbiota composition and function distinguish these phenotypes and predict multidimensional responses to pain self-management interventions in young adults with IBS. DESIGN: Ancillary data analysis from a randomized control trial (NCT03332537). METHODS: Participants with longitudinal data (n = 62) were analyzed using longitudinal k-means clustering (KML) based on trajectories of measures in IBS quality of life (QOL), Brief Pain Inventory (BPI), and psychoneurological outcomes (anxiety, applied cognition, depression, fatigue, global health, positive affect, and sleep disturbance) over 12 weeks. Baseline differences between clusters were assessed with Wilcoxon rank-sum tests, and longitudinal changes were evaluated with linear mixed models. Gut microbiota composition and predicted functional pathways were compared between phenotypes. Bayesian Additive Regression Trees (BART) models were used to identify baseline microbial taxa and pathways predictive of longitudinal changes in QOL, BPI pain interference, and severity. RESULTS: Two distinct trajectory-defined response phenotypes were identified: a Constrained Response Phenotype (Phenotype A, n = 35) and an Adaptive Multidomain Response Phenotype (Phenotype B, n = 27). At baseline, Phenotype B showed lower pain severity and interference, but higher levels of anxiety, depression, and fatigue compared to Phenotype A. Over 12 weeks, both phenotypes showed improvements in pain outcomes (all p < 0.05), but only Phenotype B demonstrated broad improvements across psychoneurological domains and QOL (all p < 0.05). Phenotype A exhibited more limited improvements and worsening in several psychoneurological domains. Gut microbiota functional pathways differed between phenotypes, including pathways related to xenobiotic degradation, amino acid metabolism, bile secretion, and immune-related processes (all raw p < 0.05), although these did not remain significant after multiple testing correction. Machine learning models identified distinct, phenotype-specific microbial predictors of intervention response. In Phenotype A, genera such as Alistipes and Sutterella were consistently identified across models, whereas in Phenotype B, predictors included Phascolarctobacterium, Collinsella, and Parabacteroides. Functional pathways also differed between phenotypes, suggesting distinct microbiome-linked mechanisms underlying symptom trajectories and responses to pain interventions. CONCLUSIONS: Young adults with IBS exhibit distinct multidimensional response phenotypes that are associated with differential clinical and microbiome profiles. Baseline gut microbiota composition and functional capacity demonstrate phenotype-specific predictive signatures of treatment response, supporting a microbiome-informed framework for stratifying patients and advancing personalized self-management strategies in IBS.
-
Unraveling the Metabolic and Microbiome Signatures in Fecal Samples of Pregnant Women with Prenatal Depression.
Background/Objectives: Prenatal depression (PND) poses a significant threat to the health of both the mother and the developing fetus. Despite its increasing prevalence, the pathophysiology of PND is not yet fully elucidated. Methods: In this study, we aimed to investigate the fecal metabolites and gut microbiota in PND patients compared to healthy controls and to explore potential correlations between these factors. Results: Through untargeted metabolomics analysis, we identified 75 significantly altered metabolites in PND patients, of which 27 were structurally annotated and implicated key pathways, such as linoleic acid metabolism and phenylalanine, tyrosine, and tryptophan biosynthesis. Notably, two Clostridia-associated enterobacteria, unclassified_c_Clostridia and unclassified_f_Lachnospiraceae, which were enriched in the PND group, were significantly positively correlated with tyrosine and negatively correlated with multiple sulfated neurosteroids. Conclusions: Our findings underscore a robust association between gut microbiota dysbiosis and metabolic disturbances in PND, with specific alterations noted in tyrosine metabolism, sulfated neurosteroid homeostasis, and linoleic acid pathways. These dysregulated metabolites-tyrosine, sulfated neurosteroids, and linoleic acid-may serve as potential diagnostic biomarkers and therapeutic targets. Moreover, their interplay provides new insights into the pathophysiological mechanisms of PND, particularly highlighting the role of gut-brain axis signaling in neuroendocrine dysregulation and inflammatory responses. However, further large-scale studies and animal models are required to validate these findings and explore detailed mechanistic pathways.
-
Microbiota-gut-brain research: A critical analysis.
Microbiota-gut-brain (MGB) research is a fast-growing field of inquiry with important implications for how human brain function and behaviour are understood. Researchers manipulate gut microbes ("microbiota") to reveal connections between intestinal microbiota and normal brain functions (e.g., cognition, emotion, and memory) or pathological states (e.g., anxiety, mood disorders, and neural developmental disorders such as autism). Many claims are made about causal relationships between gut microbiota and human behaviour. By uncovering these relationships, MGB research aims to offer new explanations of mental health and potential avenues of treatment.So far, limited evaluation has been made of MGB's methods and its core experimental findings, many of which are extensively reiterated in copious reviews of the field. These factors, plus the self-help potential of MGB, have combined to encourage uncritical public uptake of MGB discoveries. Both social and professional media focus on the potential for dietary intervention in mental health, and causal relationships are assumed to be established.Our target article has two main aims. One is to examine critically the core practices and findings of experimental MGB research and to raise questions about them for brain and behavioural scientists who may not be familiar with the field. The other is to challenge the way in which MGB findings are presented. Our positive goal is to suggest how current problems and weaknesses may be addressed, in order for both scientific and public audiences to gain a clearer picture of MGB research and its strengths and limitations.