Beneficial microbes最新文献

Obesity is a risk factor for cardio-metabolic and neurological disease. The contribution of gut microbiota to derangements of the gut-brain axis in the context of obesity has been acknowledged, particularly through physiology modulation by short-chain fatty acids (SCFAs). Thus, probiotic interventions and administration of SCFAs have been employed with the purpose of alleviating symptoms in both metabolic and neurological disease. We investigated the effects of four butyrate-producing bacteria from the Lachnospiraceae family on the development of metabolic syndrome and behavioural alterations in a mouse model of diet-induced obesity. Male mice were fed either a high-fat diet (HFD) or an ingredient-matched control diet for 2 months, and bacteria cultures or culture medium were given by gavage to HFD-fed mice every second day. Mice were assessed through a battery of metabolic and behaviour tests, and fluxes through the gut barrier and blood-brain barrier were determined using Dextran-based tracers. One of the administered bacteria from the Coprococcus genus, which produces butyrate and formate, afforded some degree of protection against the development of obesity and its complications. Results from this study, however, are insufficient to support brain health benefits of the bacteria tested. None of the bacteria modulated permeability through the gut or blood-brain barriers. Our results suggest health benefits of a bacteria from Lachnospiraceae family, and encourage further exploration of its use as probiotic.

The causes and characteristics of gut microbiota abnormalities and whether microbiota manipulation can prevent atherosclerosis in the postmenopausal stage remain to be determined. Aortic oestrogen receptor expression, histological changes and gut microbiota in women before and after menopause were detected. Serum oestrogen levels, systemic inflammation, intestinal oestrogen receptor expression and histological changes, atherosclerosis, and gut microbiota in low density lipoprotein deletion (LDLR-∕-) female mice before and after ovariectomy were tested. This study examined aortic oestrogen receptor expression, histological changes, and gut microbiota in women before and after menopause, and tested serum oestrogen levels, systemic inflammation, intestinal oestrogen receptor expression, histological changes, atherosclerosis, and gut microbiota in low-density lipoprotein receptor knockout (LDLR-∕-) female mice before and after ovariectomy. We demonstrated that the downregulation of oestrogen and oestrogen receptors after menopause promotes gut microbiota disturbance in both women and female mice. We found that gut microbiota disturbance amplifies the intestinal barrier damage and aggravates systemic inflammation, thereby promoting atherosclerosis in female mice. Faecal microbiota transplantation and antibiotics inhibit the proinflammatory properties of gut microbiota and prevent atherosclerosis by reducing intestinal barrier damage in postmenopausal mice. Together, our study highlights the causes of gut microbiota disturbances and the role of microbiota manipulation in preventing atherosclerosis in postmenopausal stage.

Chronic unpredictable mild stress (CUMS) is a widely accepted method for inducing depressive-like states in animal models. We decided to explore the effects of CUMS on the CantonS lineage of Drosophila melanogaster, which differs from the OregonR lineage in various ways. Additionally, we wanted to investigate the potential benefits of kefir in treating these chronically stressed flies, as previous research has shown promising results in using kefir components for depression treatment. To begin, we exposed male CantonS flies to a 10-day CUMS protocol and compared them to non-stressed flies. Within the stressed group, we had two subgroups: one treated with kefir (CUMS + Kefir group) and the other treated with sertraline (positive control). We then analysed various factors including serotonin levels, brain structure, markers of oxidative damage in lipids and proteins, and behavioural manifestations such as sociability, locomotor function, and anhedonic-like behaviour. Our results showed that flies exposed to CUMS experienced a decrease in serotonin levels without any signs of degeneration. They also exhibited reduced sociability, increased motor agitation, and decreased sucrose consumption, which are all indicative of stress-induced depressive-like behaviour. However, treatment with sertraline partially reversed these effects. Interestingly, treatment with kefir not only restored serotonin levels but also improved sociability and anhedonic-like behaviours. Additionally, flies in the CUMS + Kefir group had a longer lifespan compared to their untreated counterparts. These findings suggest that kefir has multiple advantageous effects on flies subjected to the 10-day CUMS protocol. In conclusion, our study demonstrates that the CantonS lineage of D. melanogaster displays depressive-like manifestations after exposure to CUMS. Furthermore, kefir emerges as a powerful nutritional tool capable of reversing these effects and promoting beneficial outcomes in chronically stressed flies.

Treatment with probiotics can help manage chronic constipation by softening the stools and possibly acting synergistically with front-line treatments. We assessed the efficacy of Bifidobacterium animalis subsp. lactis BLa80 in maltodextrin as a food supplement in regulating the intestinal habit of subjects with chronic constipation with type 1 or 2 stools on the Bristol scale index and/or less than three stools per week. A multicentre, randomised, double-blind, placebo-controlled clinical trial was carried out in subjects aged 18 and over with chronic constipation. The study enrolled forty-six subjects who were randomised one-to-one to receive the potential probiotic in maltodextrin (n = 23) or a placebo (n = 23). Investigators assessed changes in intestinal habits by analysing the mean number of weekly stools and the stool types according to the Bristol Scale. Patients reported constipation symptoms with PAC-SYM (patient assessment of constipation - symptoms), and the impact on quality of life with PAC-QoL (patient assessment of constipation - quality of life) and GI-QLI (gastrointestinal quality of life index). Patients on the intervention group showed a greater tendency to normalise the type of stools than those in the placebo group. This difference towards regular stool types (type 3 and 4) was statistically significant at weeks 8 and 12 relative to week 4 (P-values = 0.006 and 0.027, respectively). The proportion of constipated patients in the experimental group dropped over time, while the rate slightly increased in the placebo group in a statistically significant manner at week 12 relative to week 4 ( P = 0.037). Overall, the present study shows oral intake of B. animalis subsp. lactis BLa80 in maltodextrin for 12 weeks improves intestinal habits in subjects with chronic constipation. Our study provides evidence to the efficacy and safety use of this formulation as an effective tool for improving stool consistency in constipated patients. The trial was registered at ClinicalTrials.gov: NCT05980988.

The neuropsychiatric effects of probiotics, prebiotics, and synbiotics have been gaining attention since the rise of microbial-gut-brain axis research. Nevertheless, some of the findings are inconsistent, and few studies have analysed the similarities and differences in the neuropsychiatric effects of the three comprehensively. To reveal the respective neuropsychiatric effects of probiotics, prebiotics, and synbiotics and synthesise the similarities and differences among the three effects, 47 meta-analyses with 12 types of neuropsychiatric results were integrated under an umbrella review. Probiotics, prebiotics, and synbiotics intake might all be associated with improvements in some neuropsychiatric outcomes, including neuropsychological test outcomes (probiotic and prebiotic), hepatic encephalopathy outcomes (probiotic, prebiotic, and synbiotic), instant memory in patients with Alzheimer's disease (probiotic), depressive symptoms (probiotic, prebiotic and synbiotic), mood states and psychiatric distress (probiotic), overall mental health (probiotic), neurological function (probiotic), brain-derived neurotrophic factor (BDNF) concentration (probiotic and synbiotic), and Pittsburgh Sleep Quality Index (PSQI) score (probiotic). All three are similar in that the intake of probiotics, prebiotics, and synbiotics might be associated with improvements in hepatic encephalopathy outcomes and depressive symptoms, both probiotic and synbiotic intake might be associated with elevated BDNF concentrations, and both probiotic and prebiotic intake might be associated with improved neuropsychological test results. The difference between the three is that the neuropsychiatric effects of probiotics might be more widespread and be reflected in the fact that probiotic intake might also be associated with improvements in mood states and psychiatric distress, overall mental health, neurological function, Alzheimer's disease patients' instant memory, and PSQI score. Probiotics might be the best and most promising option for improving neuropsychiatric outcomes. In the future, in addition to requiring more high-quality meta-analyses, further preclinical studies are needed to explore specific relevant mechanisms and determine true causal relationships.

Epidemiologic studies have implicated the gut microbiota in acute kidney injury (AKI), but the causal relationship is unclear. Using Mendelian randomisation, we explored the causal role of gut microbiota in the development of acute kidney injury after excluding confounding and reverse causality. Mendel randomised (MR) study was conducted using data from intestinal microbiota and genome-wide association studies (GWAS) disease of acute kidney injury and the sequencing data of case-control study confirmed this finding. The summary statistics of intestinal microbiota (n = 13,266) conducted by MiBioGen Alliance was taken as the exposure, while the statistics of acute kidney injury obtained from FinnGen Alliance data (2,383 cases and 212,841 controls) were taken as the results. A total of 42 patients were included in this case-control study. Evidence for the protective causal associations of the genus Flavonifractor id.2059 with AKI was found in inverse variance weighting (odds ratio = 0.48 [95% confidence interval, 0.32-0.72]; P = 0.0003). Additionally, a case-control study showed that the relative abundance of the genus Flavonifractor id.2059 ( P = 0.0169) in septic non-AKI patients was higher than that in septic AKI patients. Compared with S-AKI patients who died within 28 days, the relative abundance of the genus Flavonifractor id.2059 in surviving patients was higher ( P = 0.0281). Phylogenetic analysis showed that OTU68 and HQ455040.1334-739 (genus Flavonifractor, Genetic similarity: 100%), as well as OTU2271 and LT598575.1365-770 (genus Pseudoflavonifractor, Genetic similarity: 100%), have closest genetic ties. Correlation analysis showed that the genus Flavonifractor id.2059 was related to the creatinine value (Spearman correlation: -0.379, P = 0.013). The present study demonstrates that the genus Flavonifractor id.2059 is associated with a reduced risk of AKI, revealing potential implications for the prevention and treatment of acute kidney injury.

The gut microbiome and the microbial metabolome contribute to treatment efficacy and treatment outcomes across the cancer care spectrum. This study systematically reviewed the existing literature between 2007 to March 2022 to elucidate the role of gut microbiota-metabolite biomarkers in colorectal cancer (CRC) care and treatment-related outcomes. Using Covidence, all studies identified were screened by title and abstract, followed by a full-text review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and data extraction. We analysed 13 non-experimental and 9 experimental CRC studies and found that, usually, the α-diversity of the gut microbiome and short-chain fatty acids decreased in CRC patients, while amino acids (e.g. glutamate) increased in CRC patients. Correlations between specific gut microbial taxa and metabolites were identified, with amino acids, fatty acids, and glycerol positively associated with certain gut microbes. Interventions promoting gut microbes and microbial metabolites associated with better health outcomes (e.g. Bifidobacterium, Lactobacillus, butyric acid, and bile acid) can potentially promote treatment efficacy and improve cancer care outcomes. Gut microbial metabolism should be integrated into targeted cancer interventions for CRC patients, given the confirmed role of the gut microbiome and metabolome pathways across the CRC care continuum.

LifeinU™ Bacillus subtilis CU1 (BSCU1) has been previously shown to be effective in stimulating mucosal immune responses and supporting resistance to common infectious disease episodes in the elderly. The current clinical study aimed at exploring potential pathways by which BSCU1 could beneficially modulate the immune system and contribute to protection against infection in the general population. A total of 88 participants from three different age groups were supplemented with BSCU1 (2 × 109 cfu/day) for 4 weeks. The effect of the intervention on mucosal immunity was assessed by faecal sIgA levels. In addition, a series of complementary immunoassays were selected, including immune phenotyping, gene expression, basal cytokine levels, cytokine levels in lipopolysaccharide (LPS)-stimulated whole blood and phagocytosis assay. Although no significant effect was observed on faecal sIgA levels after intervention, BSCU1 showed a positive effect on a consistent set of markers of the peripheral innate immune system in adults and the elderly. Percentages of peripheral blood myeloid cells as well as the expression of the activation marker CD69 on monocytes were significantly increased after probiotic intervention. BSCU1 supplementation resulted in significant enrichment of clusters of genes involved in response to type I interferon and phagocytosis pathway. Consistently, ex vivo stimulation of whole blood with LPS resulted in a statistically significant increase in pro-inflammatory cytokines (interleukin (IL)-1beta, IL-6, interferon-gamma, IL-12, tumour necrosis factor (TNF)-alpha, macrophage inflammatory protein (MIP)-1alpha, IL-8) and phagocytosis assays showed increased capacity of monocytes to engulf bacteria as well as higher phagosome maturation. BSCU1 supplementation also had a positive effect on low-grade inflammation as significant reduction in basal levels of several serum cytokines (IL-10, TNF-alpha, MIP-1alpha, IL-8) were observed in the elderly subgroup. Overall, BSCU1 primed immune cells for a better response to microbial challenges and reduced low-grade inflammation associated with aging. Registered at ClinicalTrials.gov with the identifier NCT05403398.

This systematic review aimed to compile various research designs, including experimental, longitudinal, cross-sectional, and case studies in humans and experimental studies in rodents, to examine changes in Akkermansia muciniphila abundance in response to exercise. This comprehensive approach can improve our understanding of A. muciniphila response to physical exercise and highlight gaps in the literature, providing valuable insights for future microbiome research. Four databases (Web of Science, PubMed, Scopus, and Sports Discuss) were searched in the literature. Quality assessment was conducted independently and in duplicate using two risk-of-bias tools (Downs and Black for human studies and SYRCLE's risk of bias for animal studies). 3,901 studies were identified, with thirteen human studies and nine animal studies included after screening. Of the thirteen human studies analysed, five (38.5%) were cross-sectional, seven (53.8%) were longitudinal/experimental, and one (7.7%) was a case study. These studies included 522 participants, among whom 157 were athletes, such as rugby players, marathon runners, triathletes, and skiers. Six studies reported an increase in A. muciniphila, five showed a decrease, and two found no significant differences. Regarding interventions, two studies used a combination of moderate-intensity strength and aerobic training, while seven used low to moderate-intensity aerobic exercises. In the nine rodent studies, eight (88.9%) were conducted on mice and one (11.1%) on rats, with all being experimental. These studies involved 310 animals. Eight studies reported a substantial increase in A. muciniphila, while one found no differences. Among these, eight employed moderate-intensity aerobic exercises as the intervention, and one utilised low-to-moderate-intensity strength training. The studies summarised in this review indicate that the impact of various physical exercise protocols on A. muciniphila abundance in humans remains controversial. However, rodent studies provide strong evidence that aerobic exercise increases A. muciniphila abundance in faecal pellets of both healthy and diseased models.