Browsing by Subject "MICROBIOTA"

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Now showing items 21-26 of 26
  • Bui, Thi Phuong Nam; Ritari, Jarmo; Boeren, Sjef; de Waard, Pieter; Plugge, Caroline M.; de Vos, Willem M. (2015)
    Human intestinal bacteria produce butyrate, which has signalling properties and can be used as energy source by enterocytes thus influencing colonic health. However, the pathways and the identity of bacteria involved in this process remain unclear. Here we describe the isolation from the human intestine of Intestinimonas strain AF211, a bacterium that can convert lysine stoichiometrically into butyrate and acetate when grown in a synthetic medium. Intestinimonas AF211 also converts the Amadori product fructoselysine, which is abundantly formed in heated foods via the Maillard reaction, into butyrate. The butyrogenic pathway includes a specific CoA transferase that is overproduced during growth on lysine. Bacteria related to Intestinimonas AF211 as well as the genetic coding capacity for fructoselysine conversion are abundantly present in colonic samples from some healthy human subjects. Our results indicate that protein can serve as a source of butyrate in the human colon, and its conversion by Intestinimonas AF211 and related butyrogens may protect the host from the undesired side effects of Amadori reaction products.
  • Hemida, Manal B. M.; Salin, Siru; Vuori, Kristiina A.; Moore, Robin; Anturaniemi, Johanna; Rosendahl, Sarah; Barrouin-Melo, Stella Maria; Hielm-Bjorkman, Anna (2021)
    Background The increased prevalence of atopic dermatitis (AD) in dogs necessitates research in its disease etiology. Objectives To explore the association between puppyhood dietary exposures and prevalence of owner-reported allergy/atopy skin signs (AASS) after the age of 1 year. Animals Four thousand and twenty-two dogs were eligible, 1158 cases, and 2864 controls. Methods This cross-sectional hypothesis-driven observational study was extracted from the DogRisk food frequency questionnaire. Forty-six food items and the ratio of 4 major diet types were tested for their association with AASS incidence later in life. Potential puppyhood dietary risk factors for AASS incidence were specified using binary multivariable logistic regression. The model was adjusted for age and sex. Results Eating raw tripe (odds ratio, 95% confidence intervals OR, 95% CI = 0.36, 0.16-0.79; P = .01), raw organ meats (OR, 95% CI = 0.23, 0.08-0.67; P = .007), human meal leftovers, and fish oil supplements as well as eating more that 20% of the diet as raw and/or
  • Åberg, Fredrik; Savikko, Johanna; Anttila, Veli-Jukka; Mäkisalo, Heikki (2018)
    In an intestinal transplant patient under triple immunosuppression therapy with tacrolimus levels > 10 ng/L, a 2-day oral immunoglobulin therapy given as treatment for chronic norovirus infection was temporally closely associated with the development of severe steroid-resistant acute graft rejection, thus suggesting that oral immunoglobulin might be able to promote a rejection response.
  • Kleerebezem, Michiel; Binda, Sylvie; Bron, Peter A.; Grosso, Gabriele; Hi, Colin; Vlieg, Johan E. T. van Hylckama; Lebeer, Sarah; Satokari, Reetta; Ouwehand, Arthur C. (2019)
    The different levels of knowledge described in a translational pipeline (the connection of molecular mechanisms with pre-clinical physiological and human health effects) are not complete for many probiotics. At present, we are not in a position to fully understand the mechanistic basis of many well established probiotic health benefits which, in turn, limits our ability to use mechanisms to predict which probiotics are likely to be effective in any given population. Here we suggest that this concept of a translation pipeline connecting mechanistic insights to probiotic efficacy can support the selection and production of improved probiotic products. Such a conceptual pipeline would also provide a framework for the design of clinical trials to convincingly demonstrate the benefit of probiotics to human health in well-defined subpopulations.
  • Shetty, Sudarshan A.; Boeren, Sjef; Bui, Thi P. N.; Smidt, Hauke; de Vos, Willem M. (2020)
    Thed- andl-forms of lactate are important fermentation metabolites produced by intestinal bacteria but are found to negatively affect mucosal barrier function and human health. Both enantiomers of lactate can be converted with acetate into the presumed beneficial butyrate by a phylogenetically related group of anaerobes, includingAnaerobutyricumandAnaerostipesspp. This is a low energy yielding process with a partially unknown pathway inAnaerobutyricumandAnaerostipesspp. and hence, we sought to address this via a comparative genomics, proteomics and physiology approach. We compared growth ofAnaerobutyricum soehngeniion lactate with that on sucrose and sorbitol. Comparative proteomics revealed complete pathway of butyrate formation from sucrose, sorbitol and lactate. Notably, a gene cluster,lctABCDEFwas abundantly expressed when grown on lactate. This gene cluster encodes a lactate dehydrogenase (lctD), electron transport proteins A and B (lctCB), nickel-dependent racemase (lctE), lactate permease (lctF) and short-chain acyl-CoA dehydrogenase (lctG). Investigation of available genomes of intestinal bacteria revealed this new gene cluster to be highly conserved in onlyAnaerobutyricumandAnaerostipesspp. Present study demonstrates thatA. soehngeniiand several relatedAnaerobutyricumandAnaerostipesspp. are highly adapted for a lifestyle involving lactate plus acetate utilization in the human intestinal tract.