Your browser does not allow saving data (e.g. private mode): bookmarks will be lost when the tab closes.
Search PubMed
Keywords, author, journal, years — results from PubMed, abstracts with Russian translation, bookmarks in your browser.
Found: 3 205
Page 164 of 321-
Biodegradation of polypropylene by yellow mealworms (Tenebrio molitor) and superworms (Zophobas atratus) via gut-microbe-dependent depolymerization.
Polypropylene (PP), a fossil-based polyolefin plastics widely used worldwide, is non-hydrolyzable and resistant to biodegradation as a major source of plastic pollutants in environment. This study focused on feasibility of PP biodegradation in the larvae of two species of darkling beetles (Coleoptera: Tenebrionidae) i.e., yellow mealworms (Tenebrio molitor) and superworms (Zophobas atratus) using PP foam with number-, weight-, and size-average molecular weights (Mn, Mw, and Mz) of 109.8, 356.2, and 765.0 kDa, respectively. The tests were conducted in duplicates with respective larvae (300 T. molitor and 200 Z. atratus each incubator) at 25 °C and 65% humidity for over a 35-day period. The larvae of T. molitor and Z. atratus fed with PP foam as sole diet consumed PP at 1.0 ± 0.4 and 3.1 ± 0.4 mg 100 larvae-1 days-1, respectively; when fed the PP foam plus wheat bran, the consumption rates were enhanced by 68.11% and 39.70%, respectively. Gel permeation chromatography analyses of the frass of T. molitor and Z. atratus larvae fed PP only indicated that Mw was decreased by 20.4 ± 0.8% and 9.0 ± 0.4%; Mn was increased by 12.1 ± 0.4% and 61.5 ± 2.5%; Mz was decreased by 33.8 ± 1.5% and 32.0 ± 1.1%, indicating limited extent depolymerization. Oxidation and biodegradation of PP was confirmed through analysis of the residual PP in frass. Depression of gut microbes with the antibiotic gentamicin inhibited PP depolymerization in both T. molitor and Z. atratus larvae. High throughput 16S rRNA sequencing revealed that Citrobacter sp. and Enterobacter sp. were associated with PP diets in the gut microbiome of Z. atratus larvae while Kluyvera was predominant in the T. molitor larvae. The results indicated that PP can be biodegraded in both T. molitor and Z. atratus larvae via gut microbe-dependent depolymerization with diversified microbiomes.
-
Differences in gut microbial composition correlate with regional brain volumes in irritable bowel syndrome.
BACKGROUND: Preclinical and clinical evidence supports the concept of bidirectional brain-gut microbiome interactions. We aimed to determine if subgroups of irritable bowel syndrome (IBS) subjects can be identified based on differences in gut microbial composition, and if there are correlations between gut microbial measures and structural brain signatures in IBS. METHODS: Behavioral measures, stool samples, and structural brain images were collected from 29 adult IBS and 23 healthy control subjects (HCs). 16S ribosomal RNA (rRNA) gene sequencing was used to profile stool microbial communities, and various multivariate analysis approaches were used to quantitate microbial composition, abundance, and diversity. The metagenomic content of samples was inferred from 16S rRNA gene sequence data using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt). T1-weighted brain images were acquired on a Siemens Allegra 3T scanner, and morphological measures were computed for 165 brain regions. RESULTS: Using unweighted Unifrac distances with hierarchical clustering on microbial data, samples were clustered into two IBS subgroups within the IBS population (IBS1 (n = 13) and HC-like IBS (n = 16)) and HCs (n = 23) (AUROC = 0.96, sensitivity 0.95, specificity 0.67). A Random Forest classifier provided further support for the differentiation of IBS1 and HC groups. Microbes belonging to the genera Faecalibacterium, Blautia, and Bacteroides contributed to this subclassification. Clinical features distinguishing the groups included a history of early life trauma and duration of symptoms (greater in IBS1), but not self-reported bowel habits, anxiety, depression, or medication use. Gut microbial composition correlated with structural measures of brain regions including sensory- and salience-related regions, and with a history of early life trauma. CONCLUSIONS: The results confirm previous reports of gut microbiome-based IBS subgroups and identify for the first time brain structural alterations associated with these subgroups. They provide preliminary evidence for the involvement of specific microbes and their predicted metabolites in these correlations.
-
Gut microbiota dysbiosis is associated with worse emotional states in HIV infection.
The biological mechanisms underlying emotional distress in HIV infection are likely to be complex but remain understudied. We investigated whether dysbiotic signatures in the gut microbiome of persons living with HIV (PLWH) are associated with their emotional status. We retrospectively examined the gut microbiome and clinical evaluation of 129 adults (94 PLWH and 35 HIV-) enrolled at UC San Diego's HIV Neurobehavioral Research Program. A subset of participants (32 PLWH vs. 13 HIV-) underwent an emotional assessment using the NIH Toolbox Emotion Battery summarized by three composite scores (negative affect, social satisfaction, and psychological well-being). We then sequenced the 16S rDNA V3-V4 regions from stool and performed taxonomic assignment using CLC Microbial Genomics Module. The gut microbiota profiles were evaluated in relation to participants' emotional assessment. All analyses were done in R statistical software. We found that the relative abundance of aerotolerant bacteria was significantly higher in PLWH (p < 0.01) and was associated with a lifetime major depression diagnosis independently of HIV status (p = 0.05). Moreover, PLWH experienced significantly worse psychological well-being (p = 0.02), less social satisfaction (p = 0.03), and more negative affect (p = 0.02). Higher levels of aerotolerant bacteria were associated with worse psychological well-being (rho = -0.35, p = 0.02), less social satisfaction (r = - 0.42, p < 0.01), and more negative affect (rho = 0.46, p < 0.01). The association of aerotolerant bacteria with social satisfaction and negative affect was independent of HIV status (p < 0.05, for both). The over-representation of aerotolerant bacteria in the gut may reflect worse oxidative stress and barrier defects and may contribute to emotional distress during HIV infection.
-
Positive mood-related gut microbiota in a long-term closed environment: a multiomics study based on the "Lunar Palace 365" experiment.
BACKGROUND: Psychological health risk is one of the most severe and complex risks in manned deep-space exploration and long-term closed environments. Recently, with the in-depth research of the microbiota-gut-brain axis, gut microbiota has been considered a new approach to maintain and improve psychological health. However, the correlation between gut microbiota and psychological changes inside long-term closed environments is still poorly understood. Herein, we used the "Lunar Palace 365" mission, a 1-year-long isolation study in the Lunar Palace 1 (a closed manned Bioregenerative Life Support System facility with excellent performance), to investigate the correlation between gut microbiota and psychological changes, in order to find some new potential psychobiotics to maintain and improve the psychological health of crew members. RESULTS: We report some altered gut microbiota that were associated with psychological changes in the long-term closed environment. Four potential psychobiotics (Bacteroides uniformis, Roseburia inulinivorans, Eubacterium rectale, and Faecalibacterium prausnitzii) were identified. On the basis of metagenomic, metaproteomic, and metabolomic analyses, the four potential psychobiotics improved mood mainly through three pathways related to nervous system functions: first, by fermenting dietary fibers, they may produce short-chain fatty acids, such as butyric and propionic acids; second, they may regulate amino acid metabolism pathways of aspartic acid, glutamic acid, tryptophan, etc. (e.g., converting glutamic acid to gamma-aminobutyric acid; converting tryptophan to serotonin, kynurenic acid, or tryptamine); and third, they may regulate other pathways, such as taurine and cortisol metabolism. Furthermore, the results of animal experiments confirmed the positive regulatory effect and mechanism of these potential psychobiotics on mood. CONCLUSIONS: These observations reveal that gut microbiota contributed to a robust effect on the maintenance and improvement of mental health in a long-term closed environment. Our findings represent a key step towards a better understanding the role of the gut microbiome in mammalian mental health during space flight and provide a basis for future efforts to develop microbiota-based countermeasures that mitigate risks to crew mental health during future long-term human space expeditions on the moon or Mars. This study also provides an essential reference for future applications of psychobiotics to neuropsychiatric treatments. Video Abstract.
-
Irritable bowel syndrome: a review of the general aspects and the potential role of vitamin D.
Irritable Bowel Syndrome (IBS) is a bowel disorder leading to symptoms such as abdominal pain, modifications in the motility and bowel habits, distention, bloating, and gas. Vitamin D (VD) may interfere in a plethora of cellular mechanisms, and act directly or indirectly in the regulation of the microbiome, the release of anti-microbial peptides, modulation of the immune system and inflammation processes; which in turn, may positively interfere with the altered gut function. The main purpose of this review was to survey studies involving the impacts of VD on IBS. Area covered: Eligible studies including the term VD and IBS were searched in the MEDLINE-PubMed and EMBASE (2009-2018). VD may act direct or indirectly in the regulation of the gut microbiome, immune response, and psychosocial factors that may be included in the list of IBS triggering factors. Expert opinion: Once VD plays an essential role in many processes associated with IBS, its deficiency may be associated with IBS, and the supplementation could help in the therapeutic approach for this condition. For these reasons, the understanding of the association of VD in IBS is indispensable for the development of new strategies that could improve the quality of life of the patient.
-
Effect of probiotic and prebiotic versus placebo on appetite in patients with major depressive disorder: post hoc analysis of a randomised clinical trial.
BACKGROUND: Poor appetite and weight loss are common in melancholic depression. Probiotics and prebiotics have the capacity to affect host behaviour, appetite and weight change by modulating the gut microbiome. The aim of this post hoc analysis was to investigate the effect of supplementation with probiotic and prebiotic on appetite, in parallel with body mass index (BMI), weight and energy intake, in patients with major depressive disorder (MDD). METHODS: We extracted data from a clinical trial with 81 patients. The participants were randomly assigned to receive probiotic (Lactobacillus helveticus and Bifidobacterium longum), prebiotic (galactooligosaccharide) or placebo for 8 weeks. Appetite, weight, BMI, dietary intake, serum leptin and physical activity were measured. Subjective appetite rating was evaluated every 2 weeks using visual analogue scales (VAS) to assess satiety, hunger, fullness and desire to eat. Serum leptin was measured by an enzyme-linked immunosorbent assay. Physical activity was measured using the international physical activity questionnaire. A repeated measures analysis of variance model was used to analyse VAS data and analysis of variance/analysis of covariance models for dietary intake, BMI, weight and leptin data. RESULTS: VAS data analyses indicated no significant intervention-time interactions but did show a significant increase over time for desire to eat within the probiotic group (P = 0.025). No significant difference in either BMI or weight was seen among the groups. Energy intake and leptin were significantly increased in the probiotic group compared to the prebiotic. CONCLUSIONS: Overall, probiotic supplementation for 8 weeks among MDD patients resulted in improvement of appetite, whereas prebiotic administration had no significant effect on appetite.
-
Gut microbiota mediated neuroinflammation in psychiatric disorders: Current perspectives and challenges.
Psychiatric disorders remain a major global health concern, with complex diagnostic criteria and a lack of clear biological markers that continue to challenge therapeutic strategies. Current treatment methods, such as psychotherapy, brain stimulation therapy, and pharmacological interventions, often come with their own set of side effects, thus warranting the need to explore alternative approaches. Emerging research highlights the gut brain axis (GBA) and gut microbiota (GM) as key modulators of brain health and disease. Dysbiosis, a disruption in gut microbial composition, can influence blood brain barrier (BBB) integrity, immune signaling, and microbial metabolite production, collectively modulating neuroimmune homeostasis and contributing to the onset of neuroinflammation. While growing preclinical and clinical evidence links altered GM to depression, anxiety, schizophrenia, bipolar disorder (BD), and autism spectrum disorder (ASD), causal relationships remain incompletely defined. This review examines the established and emerging mechanisms connecting the GM to neuroinflammation underlying psychiatric disorders and evaluates current microbiome targeted interventions, such as diet based strategies, probiotics, next generation probiotics (NGPs), and fecal microbiota transplantation (FMT). We also discuss speculative microbiome engineering approaches and highlight translational limitations that must be addressed before clinical implementation. A holistic approach integrating these strategies with conventional psychiatric treatments could facilitate more effective and personalized interventions.
-
The Link Between Autism Spectrum Disorder And Gastrointestinal Microbiota.
BACKGROUND: In recent times multiple attempts have been made to search for the link between Autism Spectrum Disorder (ASD) and gut microbiota. This link is not a myth as the microbiota composition and in turn its bi-products affect not only the Gut-Brain axis but also the hypothalamic-pituitary-adrenal (HPA) axis and the immune response. Aim of the study was to find the relation between the Gut Microbiota and the pathophysiology and in turn manifestations of ASD. METHODS: Eight original articles were identified by a systematic search of the MEDLINE database. Those articles were included in the review with clear mention of ASD and microbiota in titles and abstracts. RESULTS: In the majority of studies, Bacteroidetes/ Firmicutes ratio was deranged only one reported it to be normal. Bacteria such as Actinomyces and Proteobacteria were increased and Bacteroides, Bifidobacterium, Lactobacillus, and Prevotella were decreased. The commonest method of sequencing observed was 16S rRNA. CONCLUSION: The microbiota composition of the gut does affect the manifestations of autism spectrum disorder. The derangement of the gut commensals may lead to mood disorders, depression, and other symptoms in autistic kids.
-
Gut Microbiome as a Source of Probiotic Drugs for Parkinson's Disease.
Parkinson's disease (PD) is a progressive, irreversible neurodegenerative disorder characterized by motor impairments and a wide spectrum of non-motor symptoms, including gastrointestinal dysfunction, sleep disturbances, depression, and cognitive decline. These manifestations arise from disturbances across multiple systems-gastrointestinal, neuroendocrine, immune, enteric, and central nervous systems. Alterations in the gut microbiota may play a causal role in PD onset and frequently accompany disease progression. The gut-brain axis, particularly the vagus nerve, is increasingly recognized as a key communication pathway whose dysregulation contributes to systemic dysfunction and the breakdown of homeostasis, ultimately driving PD pathology. Currently, there is no cure for PD, and existing treatments primarily target symptom relief. Effective management of PD requires a comprehensive approach that integrates multiple pharmacologically active agents aimed at restoring impaired organ functions and, when possible, neutralizing toxic factors that accelerate disease progression. One promising therapeutic avenue lies in functional gut bacteria, which form the basis for developing live biotherapeutic products, postbiotics, and bacterial vesicles. In this review, we summarize current data on the effects of probiotics in PD, drawing on both animal models and clinical studies. We highlight the role of probiotics in modulating PD pathophysiology and discuss their potential as adjunctive therapeutic agents. To provide a broader perspective, we also include sections describing the clinical manifestations of PD, gut microbiota alterations associated with the disease, and the role of artificial intelligence, particularly machine learning, in constructing functional models of PD.
-
Young gut microbiota transplantation improves the metabolic health of old mice.
UNLABELLED: The gut microbiota evolves over a lifetime and significantly impacts the aging process. Targeting the gut microbiota represents a novel avenue to delay aging and aging-related physical and mental decline. However, the underlying mechanism by which the microbiota modulates the aging process, particularly age-related physical and behavioral changes is not completely understood. We conducted fecal microbiota transplantation (FMT) from young or old male donor mice to the old male recipients. Old recipients with young microbiota had a higher alpha diversity than the old recipients with old microbiota. Compared to FMT with old microbiota, FMT with young microbiota reduced body weight and prevented fat accumulation in the old recipients. FMT with young microbiota also lowered frailty, increased grip strength, and alleviated depression and anxiety-like behavior in the old recipients. Consistent with observed physical changes, untargeted metabolomic analysis of serum and stools revealed that FMT with young microbiota lowered age-related long-chain fatty acid levels and increased amino acid levels in the old recipients. Bulk RNAseq analysis of the amygdala of the brain showed that FMT with young microbiota downregulated inflammatory pathways and upregulated oxidative phosphorylation in the old recipients. Our results demonstrate that FMT with young microbiota has substantial positive influences on age-related body composition, frailty, and psychological behaviors. These effects are associated with changes in host lipid and amino acid metabolism in the periphery and transcriptional regulation of neuroinflammation and energy utilization in the brain. IMPORTANCE: The gut microbiome is a key hallmark of aging. Fecal microbiota transplantation (FMT) using young microbiota represents a novel rejuvenation strategy to delay aging. Our study provides compelling evidence that transplanting microbiota from young mice significantly improved grip strength, frailty, and body composition in aged recipient mice. At the molecular level, FMT improved aging-related metabolic markers in the gut and circulation. Additionally, FMT from young microbiota rejuvenated the amygdala of the aged brain by downregulating inflammatory pathways. This study highlights the importance of metabolic reprogramming via young microbiota FMT in improving physical and metabolic health in elderly recipients.