Browsing by Subject "GUT MICROBIOTA"

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  • Thompson, Luke R.; Sanders, Jon G.; McDonald, Daniel; Amir, Amnon; Ladau, Joshua; Locey, Kenneth J.; Prill, Robert J.; Tripathi, Anupriya; Gibbons, Sean M.; Ackermann, Gail; Navas-Molina, Jose A.; Janssen, Stefan; Kopylova, Evguenia; Vazquez-Baeza, Yoshiki; Gonzalez, Antonio; Morton, James T.; Mirarab, Siavash; Xu, Zhenjiang Zech; Jiang, Lingjing; Haroon, Mohamed F.; Kanbar, Jad; Zhu, Qiyun; Song, Se Jin; Kosciolek, Tomasz; Bokulich, Nicholas A.; Lefler, Joshua; Brislawn, Colin J.; Humphrey, Gregory; Owens, Sarah M.; Hampton-Marcell, Jarrad; Berg-Lyons, Donna; McKenzie, Valerie; Fierer, Noah; Fuhrman, Jed A.; Clauset, Aaron; Stevens, Rick L.; Shade, Ashley; Pollard, Katherine S.; Goodwin, Kelly D.; Jansson, Janet K.; Gilbert, Jack A.; Knight, Rob; Earth Microbiome Project Consortiu; Hultman, Jenni (2017)
    Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.
  • Sloan, Tim J.; Jalanka, Jonna; Major, Giles A. D.; Krishnasamy, Shanthi; Pritchard, Sue; Abdelrazig, Salah; Korpela, Katri; Singh, Gulzar; Mulvenna, Claire; Hoad, Caroline L.; Marciani, Luca; Barrett, David A.; Lomer, Miranda C. E.; de Vos, Willem M.; Gowland, Penny A.; Spiller, Robin C. (2018)
    Background & aims Ingestion of poorly digested, fermentable carbohydrates (fermentable oligo-, di-, mono-saccharides and polyols; FODMAPs) have been implicated in exacerbating intestinal symptoms and the reduction of intake with symptom alleviation. Restricting FODMAP intake is believed to relieve colonic distension by reducing colonic fermentation but this has not been previously directly assessed. We performed a randomised controlled trial comparing the effect of a low FODMAP diet combined with either maltodextrin or oligofructose on colonic contents, metabolites and microbiota. Methods A parallel randomised controlled trial in healthy adults (n = 37). All subjects followed a low FODMAP diet for a week and supplemented their diet with either maltodextrin (MD) or oligofructose (OF) 7g twice daily. Fasted assessments performed pre- and post-diet included MRI to assess colonic volume, breath testing for hydrogen and methane, and stool collection for microbiota analysis. Results The low FODMAP diet was associated with a reduction in Bifidobacterium and breath hydrogen, which was reversed by oligofructose supplementation. The difference in breath hydrogen between groups post-intervention was 27ppm (95% CI 7 to 50, P Conclusion A low FODMAP diet reduces total bacterial count and gas production with little effect on colonic volume.
  • Ottman, Noora; Geerlings, Sharon Y.; Aalvink, Steven; de Vos, Willem M.; Belzer, Clara (2017)
    The discovery of Akkermansia muciniphila has opened new avenues for the use of this abundant intestinal symbiont in next generation therapeutic products, as well as targeting microbiota dynamics. A. muciniphila is known to colonize the mucosal layer of the human intestine where it triggers both host metabolic and immune responses. A. muciniphila is particularly effective in increasing mucus thickness and increasing gut barrier function. As a result host metabolic markers ameliorate. The mechanism of host regulation is thought to involve the outer membrane composition, including the type IV pili of A. muciniphila, that directly signal to host immune receptors. At the same time the metabolic activity of A. muciniphila leads to the production of short chain fatty acids that are beneficial to the host and microbiota members. This contributes to host-microbiota and microbe-microbe syntrophy The mucolytic activity and metabolite production make A. muciniphila a key species in the mucus layer, stimulating beneficial mucosal microbial networks. This well studied member of the microbiota has been studied in three aspects that will be further described in this review: i) A. muciniphila characteristics and mucin adaptation, ii) its role as key species in the mucosal microbiome, and iii) its role in host health. (C) 2017 Published by Elsevier Ltd.
  • van der Lugt, Benthe; van Beek, Adriaan A.; Aalvink, Steven; Meijer, Ben; Sovran, Bruno; Vermeij, Wilbert P.; Brandt, Renata M. C.; de Vos, Willem M.; Savelkoul, Huub F. J.; Steegenga, Wilma T.; Belzer, Clara (2019)
    BackgroundThe use of Akkermansia muciniphila as potential therapeutic intervention is receiving increasing attention. Health benefits attributed to this bacterium include an improvement of metabolic disorders and exerting anti-inflammatory effects. The abundance of A. muciniphila is associated with a healthy gut in early mid- and later life. However, the effects of A. muciniphila on a decline in intestinal health during the aging process are not investigated yet. We supplemented accelerated aging Ercc1(-/7) mice with A. muciniphila for 10weeks and investigated histological, transcriptional and immunological aspects of intestinal health.ResultsThe thickness of the colonic mucus layer increased about 3-fold after long-term A. muciniphila supplementation and was even significantly thicker compared to mice supplemented with Lactobacillus plantarum WCFS1. Colonic gene expression profiles pointed towards a decreased expression of genes and pathways related to inflammation and immune function, and suggested a decreased presence of B cells in colon. Total B cell frequencies in spleen and mesenteric lymph nodes were not altered after A. muciniphila supplementation. Mature and immature B cell frequencies in bone marrow were increased, whereas B cell precursors were unaffected. These findings implicate that B cell migration rather than production was affected by A. muciniphila supplementation. Gene expression profiles in ileum pointed toward a decrease in metabolic- and immune-related processes and antimicrobial peptide production after A. muciniphila supplementation. Besides, A. muciniphila decreased the frequency of activated CD80(+)CD273(-) B cells in Peyer's patches. Additionally, the increased numbers of peritoneal resident macrophages and a decrease in Ly6C(int) monocyte frequencies in spleen and mesenteric lymph nodes add evidence for the potentially anti-inflammatory properties of A. muciniphila.ConclusionsAltogether, we show that supplementation with A. muciniphila prevented the age-related decline in thickness of the colonic mucus layer and attenuated inflammation and immune-related processes at old age. This study implies that A. muciniphila supplementation can contribute to a promotion of healthy aging.
  • Neuman, Manuela G.; French, Samuel W.; Zakhari, Samir; Malnick, Stephen; Seitz, Helmut K.; Cohen, Lawrence B.; Salaspuro, Mikko; Voinea-Griffin, Andreea; Barasch, Andrei; Kirpich, Irina A.; Thomes, Paul G.; Schrum, Laura W.; Donohue, Terrence M.; Kharbanda, Kusum K.; Cruz, Marcus; Opris, Mihai (2017)
    This paper is based upon the "8th Charles Lieber's Satellite Symposium" organized by Manuela G. Neuman at the Research Society on Alcoholism Annual Meeting, on June 25, 2016 at New Orleans, Louisiana, USA. The integrative symposium investigated different aspects of alcohol-induced liver disease (ALD) as well as non alcohol -induced liver disease (NAFLD) and possible repair. We revealed the basic aspects of alcohol metabolism that may be responsible for the development of liver disease as well as the factors that determine the amount, frequency and which type of alcohol misuse leads to liver and gastrointestinal diseases. We aimed to (1) describe the immuno-pathology of ALD, (2) examine the role of genetics in the development of alcoholic hepatitis (ASH) and NAFLD, (3) propose diagnostic markers of ASH and non-alcoholic steatohepatitis (NASH), (4) examine age and ethnic differences as well as analyze the validity of some models, (5) develop common research tools and biomarkers to study alcohol-induced effects, 6) examine the role of alcohol in oral health and colon and gastrointestinal cancer and (7) focus on factors that aggravate the severity of organ-damage. The present review includes pre-clinical, translational and clinical research that characterizes ALD and NAFLD. Strong clinical and experimental evidence lead to recognition of the key toxic role of alcohol in the pathogenesis of ALD with simple fatty infiltrations and chronic alcoholic hepatitis with hepatic fibrosis or cirrhosis. These latter stages may also be associated with a number of cellular and histological changes, including the presence of Mallory's hyaline, megamitochondria, or perivenular.and perisinusoidal fibrosis. Genetic polymorphisms of ethanol metabolizing enzymes and cytochrome p450 (CYP) 2E1 activation may change the severity of ASH and NASH. Other risk factors such as its co-morbidities with chronic viral hepatitis in the presence or absence of human deficiency virus were discussed. Dysregulation of metabolism, as a result of ethanol exposure, in the intestine leads to colon carcinogenesis. The hepatotoxic effects of ethanol undermine the contribution of malnutrition to the liver injury. Dietary interventions such as micro and macronutrients, as well as changes to the microbiota have been suggested. The clinical aspects of NASH, as part of the metabolic syndrome in the aging population, have been presented. The symposium addressed mechanisms and biomarkers of alcohol induced damage to different organs, as well as the role of the microbiome in this dialog. The microbiota regulates and acts as a key element in harmonizing immune responses at intestinal mucosal surfaces. It is known that microbiota is an inducer of proinflammatory T helper 17 cells and regulatory T cells in the intestine. The signals at the sites of inflammation mediate recruitment and differentiation in order to remove inflammatory inducers and promote tissue homeostasis restoration. The change in the intestinal microbiota also influences the change in obesity and regresses the liver steatosis. Evidence on the positive role of moderate alcohol consumption on heart and metabolic diseases as well on reducing steatosis have been looked up. Moreover nutrition as a therapeutic intervention in alcoholic liver disease has been discussed. In addition to the original data, we searched the literature (2008-2016) for the latest publication on the described subjects. In order to obtain the updated data we used the usual engines (Pub Med and Google Scholar). The intention of the eighth symposia was to advance the international profile of the biological research on alcoholism. We also wish to further our mission of leading the forum to progress the science and practice of translational research in alcoholism. (C) 2017 Elsevier Inc. All rights reserved.
  • Mardinoglu, Adil; Wu, Hao; Bjornson, Elias; Zhang, Cheng; Hakkarainen, Antti; Räsänen, Sari M.; Lee, Sunjae; Mancina, Rosellina M.; Bergentall, Mattias; Pietiläinen, Kirsi H.; Söderlund, Sanni; Matikainen, Niina; Stahlman, Marcus; Bergh, Per-Olof; Adiels, Martin; Piening, Brian D.; Graner, Marit; Lundbom, Nina; Williams, Kevin J.; Romeo, Stefano; Nielsen, Jens; Snyder, Michael; Uhlen, Mathias; Bergstrom, Goran; Perkins, Rosie; Marschall, Hanns-Ulrich; Backhed, Fredrik; Taskinen, Marja-Riitta; Boren, Jan (2018)
    A carbohydrate-restricted diet is a widely recommended intervention for non-alcoholic fatty liver disease (NAFLD), but a systematic perspective on the multiple benefits of this diet is lacking. Here, we performed a short-term intervention with an isocaloric low-carbohydrate diet with increased protein content in obese subjects with NAFLD and characterized the resulting alterations in metabolism and the gut microbiota using a multi-omics approach. We observed rapid and dramatic reductions of liver fat and other cardiometabolic risk factors paralleled by (1) marked decreases in hepatic de novo lipogenesis; (2) large increases in serum beta-hydroxybutyrate concentrations, reflecting increased mitochondrial beta-oxidation; and (3) rapid increases in folate-producing Streptococcus and serum folate concentrations. Liver transcriptomic analysis on biopsy samples from a second cohort revealed downregulation of the fatty acid synthesis pathway and upregulation of folate-mediated one-carbon metabolism and fatty acid oxidation pathways. Our results highlight the potential of exploring diet-microbiota interactions for treating NAFLD.
  • Bui, Thi Phuong Nam; Troise, Antonio Dario; Fogliano, Vincenzo; de Vos, Willem M. (2019)
    Modifications of lysine contribute to the amount of dietary advanced glycation end-products reaching the colon. However, little is known about the ability of intestinal bacteria to metabolize dietary N-epsilon-carboxymethyllysine (CML). Successive transfers of fecal microbiota in growth media containing CML were used to identify and isolate species able to metabolize CML under anaerobic conditions. From our study, only donors exposed to processed foods degraded CML, and anaerobic bacteria enrichments from two of them used 77 and 100% of CML. Oscillibacter and Cloacibacillus evryensis increased in the two donors after the second transfer, highlighting that the bacteria from these taxa could be candidates for anaerobic CML degradation. A tentative identification of CML metabolites produced by a pure culture of Cloacibacillus evryensis was performed by mass spectrometry: carboxymethylated biogenic amines and carboxylic acids were identified as CML degradation products. The study confirmed the ability of intestinal bacteria to metabolize CML under anoxic conditions.
  • He, Suxu; Ran, Chao; Qin, Chubin; Li, Shuning; Zhang, Hongling; de Vos, Willem M.; Ringo, Einar; Zhou, Zhigang (2017)
    In this study, we tested the distribution of 49 Lactobacillus strains in the mucus and mucosa of the intestine tissue of zebrafish. We observed a progressive change in the spatial distribution of Lactobacillus strains, and suggested a division of the strains into three classes: mucus type (>70% in mucus), mucosa type (>70% in mucosa) and hybrid type (others). The hybrid type strains were more efficient in protection of zebrafish against Aeromonas hydrophila infection. Three strains representing different distribution types (JCM1149, CGMCC1.2028, and JCM 20300) were selected. The mucosa type strain JCM1149 induced higher intestinal expression of inflammatory cytokines and Hsp70 than the other strains. Furthermore, we used L. rhamnosus GG and its mutant (PB22) lacking SpaCBA pili to investigate the influence of pili on spatial distribution. LGG showed a mucosa type distribution, while PB22 revealed a hybrid distribution and the disease protection was accordingly improved. The different protection ability between LGG and PB22 did not involve the intestinal microbiota, however, LGG induced injury to the mucosa of zebrafish. Collectively, the disease protection activity of Lactobacillus in zebrafish is correlated with their spatial distribution in the intestinal tissue, with strains showing a balanced distribution (hybrid type) more efficient in protection.
  • Talja, Ija; Kubo, Anna-Liisa; Veijola, Riitta; Knip, Mikael; Simell, Olli; Ilonen, Jorma; Vaha-Makila, Mari; Sepp, Epp; Mikelsaar, Marika; Utt, Meeme; Uibo, Raivo (2014)
  • Raju, Sajan C.; Viljakainen, Heli; Figueiredo, Rejane A. O.; Neuvonen, Pertti J.; Eriksson, Johan G.; Weiderpass, Elisabete; Rounge, Trine B. (2020)
    Background: The human microbiota contributes to health and well-being. Antimicrobials (AM) have an immediate effect on microbial diversity and composition in the gut, but next to nothing is known about their long-term contribution to saliva microbiota. Our objectives were to investigate the long-term impact of AM use on saliva microbiota diversity and composition in preadolescents. We compared the lifetime effects by gender and AMs. We used data from 808 randomly selected children in the Finnish Health In Teens (Fin-HIT) cohort with register-based data on AM purchases from the Social Insurance Institution of Finland. Saliva microbiota was assessed with 16S rRNA (V3-V4) sequencing. The sequences were aligned to the SILVA ribosomal RNA database and classified and counted using the mothur pipeline. Associations between AM use and alpha-diversity (Shannon index) were identified with linear regression, while associations between beta-diversity (Bray-Curtis dissimilarity) and low, medium or high AM use were identified with PERMANOVA. Results: Of the children, 53.6% were girls and their mean age was 11.7 (0.4) years. On average, the children had 7.4 (ranging from 0 to 41) AM prescriptions during their lifespan. The four most commonly used AMs were amoxicillin (n= 2622, 43.7%), azithromycin (n= 1495, 24.9%), amoxicillin-clavulanate (n= 1123, 18.7%) and phenoxymethylpenicillin (n= 408, 6.8%). A linear inverse association was observed between the use of azithromycin and Shannon index (b- 0.015,pvalue = 0.002) in all children, the effect was driven by girls (b- 0.032,pvalue = 0.001), while not present in boys. Dissimilarities were marked between high, medium and low users of all AMs combined, in azithromycin users specifically, and in boys with amoxicillin use. Amoxicillin and amoxicillin-clavulanate use was associated with the largest decrease in abundance ofRikenellaceae. AM use in general and phenoxymethylpenicillin specifically were associated with a decrease ofPaludibacterand pathways related to amino acid degradations differed in proportion between high and low AM users. Conclusions: A systematic approach utilising reliable registry data on lifetime use of AMs demonstrated long-term effects on saliva microbiota diversity and composition. These effects are gender- and AM-dependent. We found that frequent lifelong use of AMs shifts bacterial profiles years later, which might have unforeseen health impacts in the future. Our findings emphasise a concern for high azithromycin use, which substantially decreases bacterial diversity and affects composition as well. Further studies are needed to determine the clinical implications of our findings.
  • Ahola, Aila J; Forsblom, Carol; Groop, Per-Henrik (2018)
    Aims: Depressive mood negatively affects self-care practices, and thereby increases the risk of long-term complications. Not much is known about the association between depressive symptoms and dietary intake in patients with type 1 diabetes, a population with high risk of cardiovascular disease. Methods: Subjects (n = 976, 41% men, age 48 +/- 14 years) were participants in the Finnish Diabetic Nephropathy Study. Depressive symptomatology was assessed with the Beck Depression Inventory (BDI). Dietary patterns were derived from food frequency questionnaire-entries by exploratory factor analysis. Energy and macronutrient intakes were calculated from food records. In the same record, participants also reported the results of their daily blood glucose monitoring. Associations between BDI score and selfcare variables were analysed using generalized linear regression. For macronutrients, a substitution model was applied. Results: TWo dietary patterns ("Fish and vegetables", and "Traditional") negatively associated with the BDI score. Instead, an increase in the "Sweet" pattern score was positively associated with depressive symptomatology. Of the macronutrients, favouring protein over carbohydrates or fats associated with lower depression scores. Higher blood glucose selfmonitoring frequency and higher variability of the measurements were positively associated with the BDI score. However, no association was observed between depressive symptoms and the mean of the blood glucose measurements. Conclusions: Depressive symptoms are reflected in the dietary intake and the selfmonitoring of blood glucose, in type 1 diabetes. Whether depression, via compromised self-care practices, negatively affect long-term outcomes in this patient group has to be the subject of future studies. (C) 2018 Elsevier B.V. All rights reserved.
  • Malinen, Erja; Krogius-Kurikka, Lotta Kaisa; Lyra, Anna; Nikkila, Janne; Jaaskelainen, Anne; Rinttila, Teemu; Vilpponen-Salmela, Terttu; von Wright, Atte Johannes; Palva, Airi (2010)
  • van Soest, Annick P. M.; Hermes, Gerben D. A.; Berendsen, Agnes A. M.; van de Rest, Ondine; Zoetendal, Erwin G.; Fuentes, Susana; Santoro, Aurelia; Franceschi, Claudio; de Groot, Lisette C. P. G. M.; de Vos, Willem M. (2020)
    Dietary modulation of the gastro-intestinal microbiota is a potential target in improving healthy ageing and age-related functional outcomes, including cognitive decline. We explored the association between diet, gastro-intestinal microbiota and cognition in Dutch healthy older adults of the 'New dietary strategies addressing the specific needs of the elderly population for healthy aging in Europe' (NU-AGE) study. The microbiota profile of 452 fecal samples from 226 subjects was determined using a 16S ribosomal RNA gene-targeted microarray. Dietary intake was assessed by 7-day food records. Cognitive functioning was measured with an extensive cognitive test battery. We observed a dietary and microbial pro- to anti-inflammatory gradient associated with diets richer in animal- or plant-based foods. Fresh fruits, nuts, seeds and peanuts, red and processed meat and grain products were most strongly associated to microbiota composition. Plant-rich diets containing fresh fruits, nuts, seeds and peanuts were positively correlated with alpha-diversity, various taxa from the Bacteroidetes phylum and anti-inflammatory species, including those related to Faecalibacterium prausnitzii and Eubacterium rectale and E. biforme. Animal product-rich diets associated with pro-inflammatory species, including those related to Ruminococcus gnavus and Collinsella spp.. Cognition was neither associated with microbiota composition nor alpha-diversity. In conclusion, diets richer in animal- and plant-based foods were related to a pro- and anti-inflammatory microbial profile, while cognition was associated with neither.
  • Puhlmann, Marie-Luise; de Vos, Willem M. (2020)
    Fibers are increasingly recognized as an indispensable part of our diet and vital for maintaining health. Notably, complex mixtures of fibers have been found to improve metabolic health. Following an analysis of the fiber content of plant-based products, we found the taproot of the chicory plant (Cichorium intybus L) to be 1 of the vegetables with the highest fiber content, comprising nearly 90% of its dry weight. Chicory roots consist of a mixture of inulin, pectin, and (hemi-)cellulose and also contain complex phytochemicals, such as sesquiterpene lactones that have been characterized in detail. Nowaday, chicory roots are mainly applied as a source for the extraction of inulin, which is used as prebiotic fiber and food ingredient. Chicory roots, however, have long been consumed as a vegetable by humans. The whole root has been used for thousands of years for nutritional, medicinal, and other purposes, and it is still used in traditional dishes in various parts of the world. Here, we summarize the composition of chicory roots to explain their historic success in the human diet. We revisit the intake of chicory roots by humans and describe the different types of use along with their various methods of preparation. Hereby, we focus on the whole root in its complex, natural form, as well as in relation to its constituents, and discuss aspects regarding legal regulation and the safety of chicory root extracts for human consumption. Finally, we provide an overview of the current and future applications of chicory roots and their contribution to a fiber-rich diet.
  • Gomez, Marta; Moles, Laura; Espinosa-Martos, Irene; Bustos, Gerardo; de Vos, Willem M.; Fernandez, Leonides; Rodriguez, Juan M.; Fuentes, Susana; Jimenez, Esther (2017)
    An abnormal colonization pattern of the preterm gut may affect immune maturation and exert a long-term influence on the intestinal bacterial composition and host health. However, follow-up studies assessing the evolution of the fecal microbiota of infants that were born preterm are very scarce. In this work, the bacterial compositions of fecal samples, obtained from sixteen 2-year-old infants were evaluated using a phylogenetic microarray; subsequently, the results were compared with those obtained in a previous study from samples of meconium and feces collected from the same infants while they stayed in the neonatal intensive care unit (NICU). In parallel, the concentration of a wide range of cytokines, chemokines, growth factors and immunoglobulins were determined in meconium and fecal samples. Globally, a higher bacterial diversity and a lower interindividual variability were observed in 2-year-olds' feces, when compared to the samples obtained during their first days of life. Hospital-associated fecal bacteria, that were dominant during the NICU stay, seemed to be replaced, two years later, by genera, which are usually predominant in the healthy adult microbiome. The immune profile of the meconium and fecal samples differed, depending on the sampling time, showing different immune maturation statuses of the gut.
  • Douillard, Francois P.; de Vos, Willem M. (2019)
    Over the last decade, there has been an increasing scientific and public interest in bacteria that may positively contribute to human gut health and well-being. This interest is reflected by the ever-increasing number of developed functional food products containing health-promoting bacteria and reaching the market place as well as by the growing revenue and profits of notably bacterial supplements worldwide. Traditionally, the origin of probiotic-marketed bacteria was limited to a rather small number of bacterial species that mostly belong to lactic acid bacteria and bifidobacteria. Intensifying research efforts on the human gut microbiome offered novel insights into the role of human gut microbiota in health and disease, while also providing a deep and increasingly comprehensive understanding of the bacterial communities present in this complex ecosystem and their interactions with the gut-liver-brain axis. This resulted in rational and systematic approaches to select novel health promoting bacteria or to engineer existing bacteria with enhanced probiotic properties. In parallel, the field of gut microbiomics developed into a fertile framework for the identification, isolation and characterization of a phylogenetically diverse array of health-promoting bacterial species, also called next-generation therapeutic bacteria. The present review will address these developments with specific attention for the selection and improvement of a selected number of health-promoting bacterial species and strains that are extensively studied or hold promise for future food or pharma product development.
  • Eshriqui, Ilana; Viljakainen, Heli T.; Ferreira, Sandra; Raju, Sajan C.; Weiderpass, Elisabete; Figueiredo, Rejane A. O. (2020)
    Background Breastfeeding contributes to gastrointestinal microbiota colonization in early life, but its long-term impact is inconclusive. We aimed to evaluate whether the type of feeding during the first six months of life was associated with oral microbiota in adolescence. Methods This is a cross-sectional sub-study using baseline information of 423 adolescents from the Finnish Health in Teens (Fin-HIT) cohort. Type of feeding was recalled by parents and dichotomized as (i) No infant formula; (ii) Infant formula (breastmilk + formula or only formula). Saliva microbiota was analysed using 16S rRNA (V3-V4) sequencing. Alpha diversity and beta diversity were compared between feeding type groups using ANCOVA and PERMANOVA, respectively. Differential bacteria abundance was tested using appropriate general linear models. Results Mean age and body mass index were 11.7 years and 18.0 kg/m(2), respectively. The No formula group contained 41% of the participants. Firmicutes (51.0%), Bacteroidetes (19.1%), and Proteobacteria (16.3%) were the most abundant phyla among all participants. Alpha and beta diversity indices did not differ between the two feeding groups. Three Operational Taxonomic Units (OTUs) belonging to Eubacteria and Veillonella genera (phylum Firmicutes) were more abundant in the No formula than in the Infant formula group (log2fold changes/ p - values - 0.920/ <0.001, - 0.328/ 0.001, - 0.577/ 0.004). Conclusion Differences exist in abundances of some OTUs in adolescence according to feeding type during the first six months of life, but our findings do not support diversity and overall oral microbiota composition in adolescents being affected by early feeding type.
  • Dickson, Laura B.; Jiolle, Davy; Minard, Guillaume; Moltini-Conclois, Isabelle; Volant, Stevenn; Ghozlane, Amine; Bouchier, Christiane; Ayala, Diego; Paupy, Christophe; Moro, Claire Valiente; Lambrechts, Louis (2017)
    Conditions experienced during larval development of holometabolous insects can affect adult traits, but whether differences in the bacterial communities of larval development sites contribute to variation in the ability of insect vectors to transmit human pathogens is unknown. We addressed this question in the mosquito Aedes aegypti, a major arbovirus vector breeding in both sylvatic and domestic habitats in Sub-Saharan Africa. Targeted metagenomics revealed differing bacterial communities in the water of natural breeding sites in Gabon. Experimental exposure to different native bacterial isolates during larval development resulted in significant differences in pupation rate and adult body size but not life span. Larval exposure to an Enterobacteriaceae isolate resulted in decreased antibacterial activity in adult hemolymph and reduced dengue virus dissemination titer. Together, these data provide the proof of concept that larval exposure to different bacteria can drive variation in adult traits underlying vectorial capacity. Our study establishes a functional link between larval ecology, environmental microbes, and adult phenotypic variation in a holo-metabolous insect vector.
  • Forsgard, Richard A.; Marrachelli, Vannina G.; Korpela, Katri; Frias, Rafael; Carmen Collado, Maria; Korpela, Riitta; Monleon, Daniel; Spillmann, Thomas; Osterlund, Pia (2017)
    Purpose Chemotherapy-induced gastrointestinal toxicity (CIGT) is a complex process that involves multiple pathophysiological mechanisms. We have previously shown that commonly used chemotherapeutics 5-fluorouracil, oxaliplatin, and irinotecan damage the intestinal mucosa and increase intestinal permeability to iohexol. We hypothesized that CIGT is associated with alterations in fecal microbiota and metabolome. Our aim was to characterize these changes and examine how they relate to the severity of CIGT. Methods A total of 48 male Sprague-Dawley rats were injected intraperitoneally either with 5-fluorouracil (150 mg/kg), oxaliplatin (15 mg/kg), or irinotecan (200 mg/kg). Body weight change was measured daily after drug administration and the animals were euthanized after 72 h. Blood, urine, and fecal samples were collected at baseline and at the end of the experiment. The changes in the composition of fecal microbiota were analyzed with 16S rRNA gene sequencing. Metabolic changes in serum and urine metabolome were measured with 1 mm proton nuclear magnetic resonance (1H-NMR). Results Irinotecan increased the relative abundance of Fusobacteria and Proteobacteria, while 5-FU and oxaliplatin caused only minor changes in the composition of fecal microbiota. All chemotherapeutics increased the levels of serum fatty acids and N(CH3)(3) moieties and decreased the levels of Krebs cycle metabolites and free amino acids. Conclusions Chemotherapeutic drugs, 5-fluorouracil, oxaliplatin, and irinotecan, induce several microbial and metabolic changes which may play a role in the pathophysiology of CIGT. The observed changes in intestinal permeability, fecal microbiota, and metabolome suggest the activation of inflammatory processes.
  • Korpela, K.; Zijlmans, M. A. C.; Kuitunen, M.; Kukkonen, K.; Savilahti, E.; Salonen, Anne; de Weerth, C.; de Vos, W. M. (2017)
    Background: Children with high body mass index (BMI) at preschool age are at risk of developing obesity. Early identification of factors that increase the risk of excessive weight gain could help direct preventive actions. The intestinal microbiota and antibiotic use have been identified as potential modulators of early metabolic programming and weight development. To test if the early microbiota composition is associated with later BMI, and if antibiotic use modifies this association, we analysed the faecal microbiota composition at 3 months and the BMI at 5-6 years in two cohorts of healthy children born vaginally at term in the Netherlands (N = 87) and Finland (N = 75). We obtained lifetime antibiotic use records and measured weight and height of all children. Results: The relative abundance of streptococci was positively and the relative abundance of bifidobacteria negatively associated with the BMI outcome. The association was especially strong among children with a history of antibiotic use. Bacteroides relative abundance was associated with BMI only in the children with minimal lifetime antibiotic exposure. Conclusions: The intestinal microbiota of infants are predictive of later BMI and may serve as an early indicator of obesity risk. Bifidobacteria and streptococci, which are indicators of microbiota maturation in infants, are likely candidates for metabolic programming of infants, and their influence on BMI appears to depend on later a\ntibiotic use.