1,721,115 research outputs found
Immuno-modulatory effects of microbial metabolites of flavan-3-ols and dimeric procyanidins
No full textObjective: The gut microbiota is recognised to impact on human immune function, but we still know little about the immuno-modulating abilities of specific metabolites derived from microbiota biotransformation of dietary components. The present research aimed to evaluate the potential of microbially-derived metabolites of flavan-3-ols and dimeric procyanidins on human immune function.
Methods: Peripheral blood mononuclear cells from healthy donors were subjected to stimulation with LPS in presence or absence of different microbial polyphenol metabolites. After 5 days, T cell proliferation was measured by means of CFSE staining. IL6 and IL1B gene expression was measured after 4 hours of stimulation by real-time PCR.
Results: The results showed the immuno-modulatory potential of flavon-3-ols and procyanidins bacterial metabolites. Hydroxyphenylacetic acid was able to decrease inflammatory gene expression induced by LPS. 3,4-dihydroxyphenylpropionic acid also presented a marked anti-inflammatory capabilities, reducing IL6 and IL1B gene expression and LPS-primed T cell response.
Conclusions: Those preliminary data indicate that small phenolic acids produced by the gut microbiota upon biotransformation of complex plant polyphenols display different capabilities to regulate the inflammatory response. This has important implications for measuring the metabolic output of the gut microbiome and for identifying the molecular basis of how foods rich in polyphenols actually mediate their purported health effects in humans
Gut microbiota and health: connecting actors across the metabolic system
No full textOverweight-related metabolic diseases are an important threat to health in the Western world. Dietary habits are one of the main causative factors for metabolic syndrome, CVD and type 2 diabetes. The human gut microbiota is emerging as an important player in the interaction between diet and metabolic health. Gut microbial communities contribute to human metabolism through fermentation of dietary fibre and the result of intestinal saccharolytic fermentation is production of SCFA. Acetate, propionate and butyrate positively influence satiety, endocrine system, glucose homeostasis, adipogenesis, lipid oxidation, thermoregulation, hepatic gluconeogenesis, endothelial function and gut barrier integrity, and these mechanisms have all been linked to protection from type 2 diabetes, hypertension and cardiovascular health. The gut microbiota is also involved in bile acid metabolism and regulating their cell signalling potential, which has also been shown to modify pathways involved in metabolic health. Similarly, the gut microbiota renders recalcitrant plant polyphenols into biologically active small phenolic compounds which then act systemically to reduce metabolic disease risk. This review summarises how dietary patterns, specific foods and a healthy lifestyle may modulate metabolic health through the gut microbiota and their molecular cross-talk with the host
Tanti batteri e tanti formaggi: biodiversità microbica nel latte e nei formaggi tipici trentini
No full textComposition and evolution of ruminal fluid microbiota changes when cattle are moved from a permanent valley-farm to a temporary highland farm
No full textIntroduction: Ruminal microbiota consists in an extremely biodiverse environment, which includes bacteria, archaea, fungi and protozoa. Microbial populations contribute to the health and productivity of ruminants, and shifts when dairy cow changes diet. To this end, we investigated shifts in the ruminal bacterial and fungal communities in two groups of cows, one remaining in the permanent valley farm and the other moving to a summer highland farm. Materials and methods: Twelve healthy Brown-Swiss cows were selected from a permanent valley-farm located in Trentino (Northern East Italy). In summer 2017, 6 of the 12 cows were moved to the temporary summer farm (1,860 m altitude) for three months. The remaining cows stayed in the permanent farm over the entire duration of the study. A total of 60 ruminal fluid samples were collected monthly by using an esophageal probe, processed for microbiological analysis, extracted for genomic DNA, amplified using archaeal and fungal specific primers, sequenced on a MiSeq Illumina platform and analyzed using QIIME 2.0. Results: Ruminal fluid from cows moved to the temporary alpine farm showed increased microbial counts compared to samples collected from the permanent farm over the summer. Illumina data also showed significant changes of microbial and fungal relative abundance in alpine samples: Fibrobacter, Lachnospiraceae, Veillonellaceae and Tenericutes significantly changed among bacteria; Neocallimastigaceae, Didymosphaeriaceae, Dothideomycetes, Podospora, Filobasidium, Vishniacozyma, Basidiomycota, Aspergillus and Wallemia significantly changed among fungi. Both microbiological counts and metagenomics data at the end of summer (after transhumance) regressed to values registered at the beginning of summer (before transhumance), confirming the hypothesis that alpine pasture strongly influences the microbiota composition of ruminal liquid. Conclusions: This is the first study aiming to analyze the microbial evolution of ruminal fluid before, during, and after summer transhumance, and in particular to compare the microbiota of two groups of cows maintained over summer in the permanent farm or in a temporary highland farm, respectively. This research provides a broad picture of microbial populations residing the ruminal fluid of dairy cows reared in the permanent farm or in a temporary alpine farm, demonstrating the influence of diet, in particular of alpine pasture, on the microbial composition
Healthy dietary patterns to reduce obesity-related metabolic disease: polyphenol-microbiome interactions unifying health effects across geography
No full textPurpose of review: The spread of the Western lifestyle across the globe has led to a pandemic in obesity-related metabolic disease. The Mediterranean diet (MedDiet), Okinawa diet (OkD) and Nordic diet, derived from very different regions of the world and culinary traditions, have a large whole plant food component and are associated with reduced disease risk. This review focuses on polyphenol : microbiome interactions as one possible common mechanistic driver linking the protective effects whole plant foods against metabolic disease across healthy dietary patterns irrespective of geography.
Recent findings: Although mechanistic evidence in humans is still scarce, animal studies suggest that polyphenol or polyphenol rich foods induce changes within the gut microbiota and its metabolic output of trimethylamine N-oxide, short-chain fatty acids, bile acids and small phenolic acids. These cross-kingdom signaling molecules regulate mammalian lipid and glucose homeostasis, inflammation and energy storage or thermogenesis, physiological processes determining obesity-related metabolic and cardiovascular disease risk. However, it appears that where in the intestine metabolites are produced, the microbiota communities involved, and interactions between the metabolites themselves, can all influence physiological responses, highlighting the need for a greater understanding of the kinetics and site of production of microbial metabolites within the gut.
Summary: Interactions between polyphenols and metabolites produced by the gut microbiota are emerging as a possible unifying protective mechanism underpinning diverse healthy dietary patterns signaling across culinary traditions, across geography and across domains of life
Biodiversità microbica dei bagni di erba utilizzati per la fitobalneoterapia in Trentino
No full textPrebiotics in food and dietary supplements: a roadmap to EU health claims
No full textNumerous studies have established that prebiotic ingredients in foods and dietary supplements may play a role in supporting human health. Over the three decades that have passed since prebiotics were first defined as a concept, research has revealed a complex universe of prebiotic-induced changes to the human microbiota. There are strong indications of a direct link between these prebiotic-induced changes and specific health benefits. However, at the present time, the EU has not permitted use of the term ‘prebiotic’ in connection with an approved health claim. This paper is the outcome of a workshop organized on the 25th October 2023 by the European branch of the International Life Science Institute (ILSI). It provides an overview of the regulatory requirements for authorized health claims in the EU, key areas of prebiotic research, and findings to date in relation to prebiotics and digestive, immune, metabolic and cognitive health. Research gaps and documentation challenges are then explored and a roadmap proposed for achieving authorization of ‘prebiotic’ in the wording of future EU health claims
Food & Nutrition: The driving factors of our gut microbes
Full text linkIntroduction: The gut microbiome has attracted much attention in the last decade due to new studies and technologies revealing how gut microbes play a key role in human health and disease risk. However, we still know little about how diets, foods and nutrients shape the gut microbiome. Materials and Methods: To expand our knowledge about the complex relationship between nutrient intake and intestinal bacteria, we performed a broad dietary study covering diverse foods and nutrient intakes of nearly 100 adults. We analyzed metataxonomic data from 16S rRNA sequencing and correlated the microbial abundances of the top 55 dominant taxonomic groups with collected intakes of 40 food groups and 44 nutritional parameters, as well as degree of adherence to healthy eating patterns. Based on Spearman correlation profiles and hierarchical clustering, we also identified food groups and nutritional parameters that modulate in a similar manner microbial community structure. Results: We will present preliminary results showing direct effects of specific dietary patterns (e.g. adherence to the Mediterranean style diet), food groups (e.g., fruits, nuts, dairy) and nutrients (e.g. iron, magnesium, zinc) on specific genera of the gut microbiota. We found significant associations between alcohol and the bacterial genus Holdemania. We will show that food groups supposed to belong to the same higher-level food category do not always show the expected effect on the gut microbes, which supports the need for a detailed food classification scheme to investigate dietary effects. Similarly, we found that correlations at dietary and higher food group levels more consistently reflect existing diet:microbe associations from the literature while correlations at the nutrient level are prone to confounding factors only apparent at higher alimentary ontology. Discussion: Our study aims at a more complete understanding of the complex relations between human diet and gut microbiome community structure. Initial results confirm that both the quantity of a nutrient and the dietary source of a nutrient can both influence associations with gut bacteria. Our results may help to define new strategies for modelling diet:microbe interactions in the gut providing a new valuable tool to assist the nutrition and gut microbiome communities
Whey phage ecology in artisanal traditional ‘’hard’’ cheese: sustainability in dairy production
No full textNatural whey starters can be considered as a lactic acid bacteria culture, indispensable for the production of Italian traditional “hard” cheeses like Trentingrana. Daily maintained in the dairy activity, the main function of this culture is the acidification during the curd formation, having important effects such as whey drainage from the cocked curd and growth inhibition of photogenic and undesirable bacteria. Loss in whey starter fitness is often associated in poor acidification, mainly due to phage infection, that can strongly affect the cheese production and its final quality. Phage contamination in the dairy environment can not be completely eradicated, and there is fundamentally a co-evolution process that drives an ecological balance between phage and its microbial host, especially in whey starters environments. Therefore knowledge on phages community represent an important aspect to reduce lost in cheese production and to maintain quality and excellence in cheese making. To study the phage ecology in Trentingrana production chain, we have collected 400 samples in six Trentingrana dairies distributed on the autonomous province of Trento, Italy. Almost 1800 lactic acid bacteria have been isolated and more than 150 phages retrieved. Characterization of phage biotypes as well as phages genome sequencing is ongoing. The gaining knowledge together with the isolation of performing lactic acid bacteria resistant to phage infection, will be important to avoid milk and cheese spoilage, potentially leading to a more sustainable cheese production
Microbiota and Hepatic Encephalopathy: microbial dynamics and metabolism upon prebiotic, antibiotic and probiotic treatment
No full textObjectives: Gut microorganisms may play a fundamental role in the pathogenesis and worsening of liver disease and pathology [1], where of their composition and the production of toxic compounds are considered as trigger actors [2]. Clinically widely studied, Hepatic Encephalopathy treatment with prebiotic, antibiotic and probiotic, generally evidences a reduction of ammonia production by gut microbial activity and an increase in neurocognitive tests and mental status. Nevertheless from a strictly microbiological point of view, little is known about the dynamics, interaction and metabolite production among the main bacterial groups in liver diseases [3]. Thus we investigated, how lactulose, rifaximin or VSL#3 and their combination affect gut microbial composition, determining changes in ammonia and metabolites levels during cirrhosis treatment,Methodology: Samples in independent batch culture fermentations were used to assess microbial population dynamics using flow cytometry FISH, ammonia concentrations and short chain fatty acid production.Results: Microbial
modulation by prebiotic, antibiotic and probiotic treatment differently effect the population dynamics and its metabolism, as revealed by the different short chain fatty acid profiles and the specific increase in beneficial bacteria.Conclusions: The reduction of ammonia and regulation of metabolite production observed emphasize the importance of gut microbiota handling in HE treatment
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