Beneficial microbes最新文献

The current approaches for detecting most colorectal polyps and early neoplasms lack sufficient sensitivity and specificity, potentially hindering treatment and ultimately reducing survival rates. Here, we performed a metagenomic analysis to identify microbiome markers in stool samples from patients with early-stage colorectal cancer (CRC). We compared the composition of gut microbiota between patients with CRC and healthy individuals, specifically focusing on patients with early-stage CRC, defined as those without core mutations (KRAS, BRAF) for CRC diagnosis, stable microsatellite instability, and distant metastasis. The aim of our study is to identify potential biomarkers from gut microbiota at different cancer stages in colorectal cancer (CRC) patients through 16S rRNA amplicon sequencing, thereby proposing a novel non-invasive method for the early diagnosis of CRC. Specific microbes were detected from groups divided based on the TNM criteria, with one group classified by tumour size only (named the T group) and another group with lymph node metastasis (named the TN group). Aerobic bacteria, such as Delftia, Stenotrophomonas, Sphingobacterium, Rhodococcus, Devosia, Ensifer, and Psychrobacter were predominantly detected in patients with CRC without lymph node metastasis. The diagnostic prediction was evaluated using the CatBoost algorithm; these microbes presented high diagnostic accuracy with a receiver operating characteristics-area under curve of 0.8, which was validated using qPCR. In conclusion, this study identified specific aerobic microbial groups as non-invasive biomarkers for early diagnosis in patients with CRC without genetic or environmental factors.

Perinatal antibiotic exposure potentially leads to gut microbiota dysbiosis, which is associated with functional gastrointestinal disorders (FGIDs). We aimed to investigate the effects of Limosilactobacillus reuteri DSM 17938 supplementation on the development of FGIDs, crying and sleep duration, and the gut microbial composition in infants exposed to antibiotics during the neonatal period. In this randomised, double-blind, placebo-controlled study, we included 89 term neonates treated with antibiotics. Neonates received the study product for six weeks. FGIDs, assessed by the Infant Gastrointestinal Symptom Questionnaire, crying and sleep duration were assessed at four and eight weeks, and six months after enrolment. Faecal samples were collected six weeks and twelve months after enrolment. The gut microbial community composition was analysed using 16S amplicon sequencing and qPCR. The proportion of infants with FGIDs was greater in the control group, although the difference between the groups was significant only six months after enrolment. At all time points, the probiotic group presented a longer sleep duration and shorter crying time than the control group, but the difference was not statistically significant. Probiotic consumption had no significant effect on the gut microbiota composition except for increased L. reuteri DSM 17938 abundance in the probiotic group at six weeks after enrolment. At specific time points after supplementation with L. reuteri DSM 17938, a reduction in the prevalence of FGIDs was observed in the probiotic group. However, no observable effect on the gut microbiota was detected during the intervention. We believe that probiotic supplementation in neonates during and after antibiotic treatment to minimise the negative effects of antibiotics on gut function during this vulnerable period of human development warrants further investigation. The trial is registered at ClinicalTrials.gov (NCT02865564).

Colon target delivery of active ingredients is frequently applied in pharmaceutical products. However, in functional food and beverage applications, dietary supplements, and medical nutrition, formats targeting colonic delivery to improve human health are rare. Nevertheless, there is emerging evidence for beneficial effects of colonic delivered nutrients on gut microbiota and host health which increases the demand for sustainable food grade materials that are regulatory approved for application. In this paper, we describe a double layer coated multi-unit particle system (MUPS) with a diameter of approximately 730 microns consisting of food grade materials: shellac as outer layer, alginate as inner layer, cellulose as a core and riboflavin as active ingredient. The suitability of the MUPS for colonic delivery was tested in three well-established in vitro digestion and fermentation models: the USP Apparatus 3 and the TNO Intestinal Models 1 and 2 (TIM-1 and TIM-2). All systems confirmed the integrity of the MUPS under simulated upper gastrointestinal tract conditions with approximately 90% of the active ingredient being released under simulated ileal-colonic conditions. The TIM-2 model also showed the effects of riboflavin loaded MUPS on the microbiome composition with an increase in the production of short-chain fatty acids, acetate and butyrate. The results of these experiments provide a reliable basis for validation of this vitamin-loaded food grade MUPS in future human clinical trials. In addition, following the recent announcement of the European Commission to restrict intentionally added microplastics to products, the materials used in the described formulation offer an environmentally friendly alternative to often applied methyl acrylate based coatings.

Stress significantly affects gastrointestinal and mental health, and the gut microbiota plays a pivotal role in this process. Enterococcus faecalis strain EC-12 (EC-12) is a lactic acid bacterium that has several health benefits. To investigate the impact of oral supplementation with heat-killed EC-12 on the discomfort caused by stress, a randomised, double-blind, placebo-controlled trial was conducted with students under academic stress taking EC-12 (n = 14) or a placebo (n = 13) daily for one week. Improvement in the students' symptoms was assessed using the visual analogue scale. Faecal microbiota was characterised by next-generation sequencing of 16S rRNA genes, and faecal metabolites and short-chain fatty acids were analysed using a GC-MS metabolomics approach. Significant improvements in abdominal pain and rumbling of the stomach were found in the EC-12 group compared to the placebo group, but no changes were observed in mental symptoms or salivary cortisol levels. The relative abundance of E. faecalis significantly increased in the EC-12 group after the trial; however, the composition and diversity of the gut microbiota did not change significantly. Functional analysis of the gut microbiota suggested that EC-12 intake alters specific metabolic pathways. Although the levels of faecal short-chain fatty acids did not change between the groups before and after the trial, EC-12 intake altered the composition of faecal metabolites, with a significant increase in tryptamine levels. The ratio of students with improved symptoms to those with increased tryptamine levels was calculated based on the number of students with elevated faecal tryptamine levels who showed symptomatic improvements. The ratio of improved rumbling stomach was higher than that of other types of digestive discomfort. These results suggest that oral supplementation with EC-12 has a potentially beneficial effect on stress-induced gastrointestinal discomfort, which may occur through alterations in gut microbiota composition and metabolism. This study was registered at the University Hospital Medical Information Network Center (UMIN) under the UMIN ID: UMIN000048184.

Cow's milk protein allergy (CMPA) in infancy is associated with intestinal microbial dysbiosis, characterised by low Bifidobacteriaceae levels. The present study aimed to investigate the impact of two human milk oligosaccharides (HMO), lactose (L), and their combination on the faecal microbiome and metabolome of infants with CMPA. Stool samples of 12 term infants with probable CMPA (mean age 4.3 months) were analysed using a validated intestinal fermentation assay (SIFR® technology). For each substrate (i.e. HMO (2'-fucosyllactose [2'-FL] and lacto-N-neotetraose [LNnT]), L and HMO + L), taxonomic microbiome characterisation and untargeted metabolite profiling were performed at multiple timepoints. At baseline, the tested faecal microbiota overall displayed low abundances of Bifidobacteriaceae. Fermentation with either HMO or lactose significantly enriched Bifidobacterium breve, Bifidobacterium longum, Bifidobacterium pseudocatenulatum and, for HMO + L, also Bifidobacterium bifidum. The increase in HMO-utilising bifidobacteria was associated with a significant rise in levels of short-chain fatty acids, aromatic lactic acids and N-acetylated amino acids, with additive effects being observed for HMO + L. The above data suggest that the combination of 2'-FL, LNnT and lactose helps to alleviate the previously reported CMPA-associated intestinal bacterial dysbiosis and induces the production of several beneficial metabolites. The clinical significance of these findings for infants with CMPA requires further investigation.

Hyperlipidaemia, the abnormally high concentration of lipids such as cholesterol in the body, has a series of deleterious effects on health that are least in part are due to increased inflammation and oxidative stress. Probiotics are living microorganisms that possess the efficacy to improve health. Among the many effects that have been ascribed to probiotics is the potential to lower the body lipid content. Here, we used a rat model of induced hyperlipidaemia to assess the lipid-lowering and antioxidant properties of the probiotic strain Bifidobacterium animalis MSMC83 as well as its impact on intestinal barrier immunity and the intestinal microbiota. Oral probiotic intake led to a reduction of body weight, fasting blood glucose, and lipid levels, and increased expression of cholesterol-7α-hydroxylase and antioxidant enzymes. Additionally, B. animalis MSMC83 decreased the levels of liver enzymes and pro-inflammatory cytokines, leading to reduced hepatic steatosis. Furthermore, it re-established intestinal barrier integrity as shown by restoration of the tight junction protein zonula occludens-1 amount and reduced pathogen-induced inflammation in the intestinal epithelium as shown by readjusted expression of toll-like receptors (TLRs). Moreover B. animalis MSMC83 contributed to the maintenance of a balanced, diverse microbiome. Thus, our results indicate that B. animalis MSMC83 alleviates risk factors associated with hyperlipidaemia, suggesting its use as a probiotic to counter the effects associated with unhealthy diets.

The human gut microbiota is increasingly being recognised to play an important role in maintaining health. The families Lachnospiraceae and Oscillospiraceae in particular, are often reduced in disease states but are relatively poorly represented in culture collections. Cultured representatives are required to investigate the physiology and host interactions of gut microbes. Establishing cultured isolate collections can be laborious and expensive owing to the fastidious growth requirements of these organisms and the costs associated with taxonomic classification. This study proposes a culturomics platform combining a single basal culture medium with matrix-assisted laser adsorption/ionisation coupled to time-of-flight mass spectrometry (MALDI-TOF MS) for fast and reliable isolation and identification of hundreds of novel isolates. In this study, basal YCFA medium supplemented with either glucose, apple pectin, or porcine mucin was used to cultivate a total of 724 different isolates derived from only 11 different faecal samples from healthy volunteers, of which 389 isolates belonged to the Lachnospiraceae and Oscillospiraceae families. Moreover, 27 isolates could not be assigned to known species based on their 16S rRNA gene, 17 of which may even represent novel genera. To aid MALDI-TOF MS identification of gut bacteria, the commercial database was complemented with the MaldiGut database presented here, containing a collection of 132 different Main Spectrum Profiles, including the profiles of 125 Firmicutes species, 3 Bacteroidetes species, 3 Actinobacteria species, and one Verrucomicrobia species. The culturomics platform and MaldiGut database presented here will enable further expansion of the gut culturome, especially within the understudied Lachnospiraceae and Oscillospiraceae families.

Chronic constipation is a multi-symptomatic, multifactorial, and heterogeneous gastrointestinal disorder. Current pharmacological treatments for chronic constipation are limited and might negatively impact the patients' quality of life. Although probiotics have been shown to improve constipation symptoms, their specific regulatory mechanisms remain unclear. This study sought to explore how probiotic complexes may affect chronic constipation by improving patients' defecation habits. Furthermore, microbial profiles and non-targeted metabolites were assessed to explore the metabolic pathways involved in the improvement of constipation by probiotics. Patients with chronic constipation were treated using a single-blind, randomised, placebo-controlled trial design. The experimental group was administered Lactobacillus powder prepared from 15 probiotic products, and maltodextrin was used as a placebo. Samples were collected twice daily for 4 weeks, and faecal samples were analysed using 16S rRNA sequencing and untargeted metabolic histology. Probiotic treatment changed the makeup of the gut microbiota, enhanced the quantity of Bifidobacterium and Lactobacillus, and markedly reduced clinical symptoms. The 16S rRNA analysis revealed that the abundance of Bifidobacterium and Prevotella increased while that of Thickettsia declined. Moreover, there was a decrease in the abundance of Faecalibacterium and Roseburia. Non-targeted metabolomics analysis identified several differential metabolites, including succinic acid, fumaric acid, cholesterol, xanthurenic acid, 3-alpha,7-alpha-trihydroxy-5beta-cholestan-26-oic, and N-methyltryptamine. KEGG analysis showed that these metabolites were mainly associated with metabolic pathways such as primary bile acid biosynthesis, tryptophan metabolism, alanine, aspartate and glutamate metabolism, phenylalanine metabolism, cholesterol metabolism, and propanoate metabolism. In this study, gut microbiome and non-targeted metabolome analyses were performed on collected faecal samples to compare characteristic microorganisms and differential metabolites to provide new insights and references for probiotic intervention in constipation. Trial registered at chictr.org.cn under number: ChiCTR2200056274.

Asthma prevalence has been increasing in communities that become more urbanised. Our previous results showed that Saccharomyces cerevisiae UFMG A-905 prevented the development of asthma symptoms and characteristics in a dose-dependent manner. Perinatal programming theory proposes that early exposure to some stimuli may have a protective effect in adult life. The aim of this study was to evaluate the effects of perinatal administration of S. cerevisiae UFMG A-905 in the prevention of asthma in the offspring of mice. S. cerevisiae UFMG A-905 was cultured in YPD broth medium and administered to three groups of mice: before conception, during gestation and lactation (CGL group); during gestation and lactation (GL group); and only during lactation (L group). The offspring of these animals were sensitised and challenged with ovalbumin. Two control groups received saline in the same periods. After, in vivo measurements of airway hyperresponsiveness (AHR) were performed. Total and differential cell count in bronchoalveolar lavage (BAL); ELISA for interleukin (IL)-4, IL-5, IL-10, IL-13, and IL-17A in the lung homogenate or BAL; and ELISA for ovalbumin (OVA)-specific immunoglobulin E (IgE) were performed. The animals of the CGL, GL, and L group, when compared to the OVA group, presented a significant reduction of AHR ( P < 0.01), levels of IL-5 ( P < 0.001) in BAL, and IL-4 ( P < 0.05) and IL-13 ( P < 0.01) in the lung homogenate. Serum IgE levels were significantly higher ( P < 0.05) in CGL and GL groups when compared to the OVA group, but not in the L group. Only in the group L, there was a significant decrease in the number of total cells ( P < 0.01) and eosinophils ( P < 0.05). Perinatal administration of S. cerevisiae UFMG A-905 prevented the development of asthma-like characteristics and may be an option for asthma management. The protective effects on the offspring were more prominent when the yeast was given during lactation.

The world is witnessing an increasing incidence of chronic non-communicable diseases (NCDs), such as inflammatory bowel disease (IBD), a group of complex gastrointestinal disorders characterised by inflammation. It is believed that environmental factors, such as exposure to pollutants and endocrine-disrupting chemicals (i.e. bisphenol A [BPA]), are playing a role in IBD pathophysiology. New research suggests a potential treatment solution: next-generation probiotic (NGP) strains isolated from human gut microbiota that can biodegrade xenobiotics and thus possibly modulate IBD triggered by these xenobiotics. In this study, we hypothesised that specific BPA-tolerant bacteria would exhibit beneficial, anti-inflammatory properties that could counter the effects of BPA exposure and concomitantly reduce colitis severity. We observed that two such strains, Bacillus sp. AM1 and Paeniclostridium sp., exhibited potential anti-inflammatory properties in vitro and in vivo. First, these bacteria were able to decrease the secretion of interleukin (IL)-8 cytokines by HT-29 cells that had been exposed to the proinflammatory cytokine tumour necrosis factor (TNF)-α. Second, when treated with Bacillus sp. AM1 and Paeniclostridium sp. (this latter had a stronger reducing effect on inflammatory markers), mice with chemically induced colitis displayed lower levels of colon damage, monocyte chemotactic protein 1 (MCP-1), lipocalin-2 (LCN-2), and proinflammatory cytokines (IL-1β and IL-6). Future research should clarify the underlying mechanisms at play and identify potential strategies for counteracting the systemic effects of IBD, including those exacerbated by BPA exposure. Our results suggest that one such strategy could be treatment with BPA-tolerant bacteria that possess anti-inflammatory properties.