Oral versus intravenous iron replacement therapy distinctly alters the gut microbiota and metabolome in patients with IBD
TL;DR: Shifts in gut bacterial diversity and composition associated with iron treatment are pronounced in IBD participants, despite similar clinical outcome, oral administration differentially affects bacterial phylotypes and faecal metabolites compared with IV therapy.
Abstract: Objective Iron deficiency is a common complication in patients with IBD and oral iron therapy is suggested to exacerbate IBD symptoms. We performed an open-labelled clinical trial to compare the effects of per oral (PO) versus intravenous (IV) iron replacement therapy (IRT). Design The study population included patients with Crohn9s disease (CD; N=31), UC (N=22) and control subjects with iron deficiency (non-inflamed, NI=19). After randomisation, participants received iron sulfate (PO) or iron sucrose (IV) over 3 months. Clinical parameters, faecal bacterial communities and metabolomes were assessed before and after intervention. Results Both PO and IV treatments ameliorated iron deficiency, but higher ferritin levels were observed with IV. Changes in disease activity were independent of iron treatment types. Faecal samples in IBD were characterised by marked interindividual differences, lower phylotype richness and proportions of Clostridiales. Metabolite analysis also showed separation of both UC and CD from control anaemic participants. Major shifts in bacterial diversity occurred in approximately half of all participants after IRT, but patients with CD were most susceptible. Despite individual-specific changes in phylotypes due to IRT, PO treatment was associated with decreased abundances of operational taxonomic units assigned to the species Faecalibacterium prausnitzii , Ruminococcus bromii , Dorea sp. and Collinsella aerofaciens . Clear IV-specific and PO-specific fingerprints were evident at the level of metabolomes, with changes affecting cholesterol-derived host substrates. Conclusions Shifts in gut bacterial diversity and composition associated with iron treatment are pronounced in IBD participants. Despite similar clinical outcome, oral administration differentially affects bacterial phylotypes and faecal metabolites compared with IV therapy. Trial registration number clinicaltrial.gov (NCT01067547).
Citations
More filters
TL;DR: The Christensenellaceae, a recently described family in the phylum Firmicutes, is emerging as an important player in human health, with its relationship with BMI the most robust and reproducible link between the microbial ecology of the human gut and metabolic disease reported to date.
Abstract: The Christensenellaceae, a recently described family in the phylum Firmicutes, is emerging as an important player in human health. The relative abundance of Christensenellaceae in the human gut is inversely related to host body mass index (BMI) in different populations and multiple studies, making its relationship with BMI the most robust and reproducible link between the microbial ecology of the human gut and metabolic disease reported to date. The family is also related to a healthy status in a number of other different disease contexts, including obesity and inflammatory bowel disease. In addition, Christensenellaceae is highly heritable across multiple populations, although specific human genes underlying its heritability have so far been elusive. Further research into the microbial ecology and metabolism of these bacteria should reveal mechanistic underpinnings of their host-health associations and enable their development as therapeutics.
312 citations
TL;DR: Counterbalancing dysbiosis using Faecalibacterium prausnitzii as a potential active component of probiotic formulations appears to be a promising therapeutic strategy for inflammatory bowel diseases and colorectal cancer.
Abstract: Faecalibacterium prausnitzii, anaerobic bacteria, is one of the main components of gut microbiota and the most important butyrate-producing bacteria in the human colon. So far, this commensal bacterium has been considered as a bioindicator of human health, once when its population is altered (decreased), inflammatory processes are favored. Several reports in the literature highlighted that the amount of Faecalibacterium prausnitzii negatively correlates to the activity of inflammatory bowel disease and colorectal cancer. Therefore, counterbalancing dysbiosis using Faecalibacterium prausnitzii as a potential active component of probiotic formulations appears to be a promising therapeutic strategy for inflammatory bowel diseases and colorectal cancer. However, once this microbial is very sensitive to oxygen, the formulation development is a great challenge. In this review, we will focus our attention on Faecalibacterium prausnitzii biology, anti-inflammatory metabolites, modulators of this bacterium population and its impact on human health.
256 citations
Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico1, Bellvitge University Hospital2, University of Cantabria3, Charité4, National University of Singapore5, University of Cambridge6, University of Zurich7, Vita-Salute San Raffaele University8, University College Hospital9, Institute for Health Metrics and Evaluation10, American University of Beirut11
TL;DR: Practical recommendations for iron deficiency to treating physicians are provided: definition, diagnosis, and disease‐specific diagnostic algorithms to facilitate appropriate diagnosis and treatment to improve quality of life and clinical outcomes.
Abstract: Iron deficiency, even in the absence of anemia, can be debilitating, and exacerbate any underlying chronic disease, leading to increased morbidity and mortality. Iron deficiency is frequently concomitant with chronic inflammatory disease; however, iron deficiency treatment is often overlooked, partially due to the heterogeneity among clinical practice guidelines. In the absence of consistent guidance across chronic heart failure, chronic kidney disease and inflammatory bowel disease, we provide practical recommendations for iron deficiency to treating physicians: definition, diagnosis, and disease-specific diagnostic algorithms. These recommendations should facilitate appropriate diagnosis and treatment of iron deficiency to improve quality of life and clinical outcomes.
250 citations
Cites background from "Oral versus intravenous iron replac..."
...Moreover, oral iron treatment has recently been associated with significant changes in the normal gut microbiota, adding to our understanding of how oral iron causes its well-known GI tolerability profile, which is particularly detrimental to IBD patients.(114) The alternative solution, IV iron treatment, can deliver a larger iron supply, effectively replenishing iron stores more rapidly than oral iron and, because of the route of administration, bypassing the risk of GI side effects....
[...]
TL;DR: Current knowledge about popular diets, including the specific carbohydrate diet and diet low in fermentable oligo-, di-, and monosaccharides and polyols are discussed, to help gastroenterologists navigate diet as it relates to the management of IBD.
248 citations
TL;DR: Clinical and preclinical studies suggest that the type and amount of proteins in the diet has substantial and differential effects on the gut microbiota, and further clinical investigation of the effect of micronutrients and macronutrient on the microbiome and metabolome is warranted.
Abstract: Understanding how dietary nutrients modulate the gut microbiome is of great interest for the development of food products and eating patterns for combatting the global burden of non-communicable diseases. In this narrative review we assess scientific studies published from 2005 to 2019 that evaluated the effect of micro- and macro-nutrients on the composition of the gut microbiome using in vitro and in vivo models, and human clinical trials. The clinical evidence for micronutrients is less clear and generally lacking. However, preclinical evidence suggests that red wine- and tea-derived polyphenols and vitamin D can modulate potentially beneficial bacteria. Current research shows consistent clinical evidence that dietary fibers, including arabinoxylans, galacto-oligosaccharides, inulin, and oligofructose, promote a range of beneficial bacteria and suppress potentially detrimental species. The preclinical evidence suggests that both the quantity and type of fat modulate both beneficial and potentially detrimental microbes, as well as the Firmicutes/Bacteroides ratio in the gut. Clinical and preclinical studies suggest that the type and amount of proteins in the diet has substantial and differential effects on the gut microbiota. Further clinical investigation of the effect of micronutrients and macronutrients on the microbiome and metabolome is warranted, along with understanding how this influences host health.
238 citations
Cites methods from "Oral versus intravenous iron replac..."
...Lee et al. (2016) 1 mg/kg/day of retinoic acid, the metabolite of dietary vitamin A for 8 days and the control group as reference/mice model [75] ↑ ↑ ↑ 1 mg/kg/day of retinoic acid, the metabolite of dietary vitamin A on murine norovirus infection mice for 8 days, and the murine norovirus infection…...
[...]
References
More filters
Broad Institute1, Emory University2, Cincinnati Children's Hospital Medical Center3, University of Colorado Boulder4, Harvard University5, University of Minnesota6, University of Toronto7, Women & Children's Hospital of Buffalo8, Boston Children's Hospital9, Mayo Clinic10, University of California, San Francisco11, Long Island Jewish Medical Center12, Children's Hospital of Philadelphia13, Children's Hospital of Eastern Ontario14, Nationwide Children's Hospital15, Howard Hughes Medical Institute16
TL;DR: Comparing the microbial signatures between the ileum, the rectum, and fecal samples indicates that at this early stage of disease, assessing the rectal mucosal-associated microbiome offers unique potential for convenient and early diagnosis of CD.
2,410 citations
TL;DR: Using a rational approach to isolate CD4+FOXP3+ regulatory T (Treg)-cell-inducing bacterial strains from the human indigenous microbiota may allow for tailored therapeutic manipulation of human immune disorders.
Abstract: Manipulation of the gut microbiota holds great promise for the treatment of inflammatory and allergic diseases. Although numerous probiotic microorganisms have been identified, there remains a compelling need to discover organisms that elicit more robust therapeutic responses, are compatible with the host, and can affect a specific arm of the host immune system in a well-controlled, physiological manner. Here we use a rational approach to isolate CD4(+)FOXP3(+) regulatory T (Treg)-cell-inducing bacterial strains from the human indigenous microbiota. Starting with a healthy human faecal sample, a sequence of selection steps was applied to obtain mice colonized with human microbiota enriched in Treg-cell-inducing species. From these mice, we isolated and selected 17 strains of bacteria on the basis of their high potency in enhancing Treg cell abundance and inducing important anti-inflammatory molecules--including interleukin-10 (IL-) and inducible T-cell co-stimulator (ICOS)--in Treg cells upon inoculation into germ-free mice. Genome sequencing revealed that the 17 strains fall within clusters IV, XIVa and XVIII of Clostridia, which lack prominent toxins and virulence factors. The 17 strains act as a community to provide bacterial antigens and a TGF-β-rich environment to help expansion and differentiation of Treg cells. Oral administration of the combination of 17 strains to adult mice attenuated disease in models of colitis and allergic diarrhoea. Use of the isolated strains may allow for tailored therapeutic manipulation of human immune disorders.
2,242 citations
TL;DR: The metagenomic approach allowed us to detect a reduced complexity of the bacterial phylum Firmicutes as a signature of the faecal microbiota in patients with CD, and indicated the presence of new bacterial species.
Abstract: Background and aim: A role for the intestinal microbial community (microbiota) in the onset and chronicity of Crohn’s disease (CD) is strongly suspected. However, investigation of such a complex ecosystem is difficult, even with culture independent molecular approaches.
Methods: We used, for the first time, a comprehensive metagenomic approach to investigate the full range of intestinal microbial diversity. We used a fosmid vector to construct two libraries of genomic DNA isolated directly from faecal samples of six healthy donors and six patients with CD. Bacterial diversity was analysed by screening the two DNA libraries, each composed of 25 000 clones, for the 16S rRNA gene by DNA hybridisation.
Results: Among 1190 selected clones, we identified 125 non-redundant ribotypes mainly represented by the phyla Bacteroidetes and Firmicutes. Among the Firmicutes, 43 distinct ribotypes were identified in the healthy microbiota, compared with only 13 in CD (p<0.025). Fluorescent in situ hybridisation directly targeting 16S rRNA in faecal samples analysed individually (n = 12) confirmed the significant reduction in the proportion of bacteria belonging to this phylum in CD patients (p<0.02).
Conclusion: The metagenomic approach allowed us to detect a reduced complexity of the bacterial phylum Firmicutes as a signature of the faecal microbiota in patients with CD. It also indicated the presence of new bacterial species.
2,074 citations
TL;DR: Dietary fats, by promoting changes in host bile acid composition, can markedly alter conditions for gut microbial assemblage, resulting in dysbiosis that can perturb immune homeostasis, providing a plausible mechanistic basis by which Western-type diets high in certain saturated fats might increase the prevalence of complex immune-mediated diseases like inflammatory bowel disease in genetically susceptible hosts.
Abstract: The composite human microbiome of Western populations has probably changed over the past century, brought on by new environmental triggers that often have a negative impact on human health. Here we show that consumption of a diet high in saturated (milk-derived) fat, but not polyunsaturated (safflower oil) fat, changes the conditions for microbial assemblage and promotes the expansion of a low-abundance, sulphite-reducing pathobiont, Bilophila wadsworthia. This was associated with a pro-inflammatory T helper type 1 (T(H)1) immune response and increased incidence of colitis in genetically susceptible Il10(−/−), but not wild-type mice. These effects are mediated by milk-derived-fat-promoted taurine conjugation of hepatic bile acids, which increases the availability of organic sulphur used by sulphite-reducing microorganisms like B. wadsworthia. When mice were fed a low-fat diet supplemented with taurocholic acid, but not with glycocholic acid, for example, a bloom of B. wadsworthia and development of colitis were observed in Il10(−/−) mice. Together these data show that dietary fats, by promoting changes in host bile acid composition, can markedly alter conditions for gut microbial assemblage, resulting in dysbiosis that can perturb immune homeostasis. The data provide a plausible mechanistic basis by which Western-type diets high in certain saturated fats might increase the prevalence of complex immune-mediated diseases like inflammatory bowel disease in genetically susceptible hosts.
1,388 citations
TL;DR: The composition of the fecal microbiota of UC patients differs from that of healthy individuals: the authors found a reduction in R hominis and F prausnitzii, both well-known butyrate-producing bacteria of the Firmicutes phylum, suggesting that different bacterial species contribute to the pathogenesis of UC and CD.
Abstract: Objective Bacteria play an important role in the onset and perpetuation of intestinal inflammation in inflammatory bowel disease (IBD). Unlike in Crohn9s disease (CD), in which dysbiosis has been better characterised, in ulcerative colitis (UC), only small cohorts have been studied and showed conflicting data. Therefore, we evaluated in a large cohort if the microbial signature described in CD is also present in UC, and if we could characterise predominant dysbiosis in UC. To assess the functional impact of dysbiosis, we quantified the bacterial metabolites. Design The predominant microbiota from 127 UC patients and 87 age and sex-matched controls was analysed using denaturing gradient gel electrophoresis (DGGE) analysis. Differences were quantitatively validated using real-time PCR. Metabolites were quantified using gas chromatography–mass spectrometry. Results Based on DGGE analysis, the microbial signature previously described in CD was not present in UC. Real-time PCR analysis revealed a lower abundance of Roseburia hominis (p Faecalibacterium prausnitzii (p Conclusions The composition of the fecal microbiota of UC patients differs from that of healthy individuals: we found a reduction in R hominis and F prausnitzii, both well-known butyrate-producing bacteria of the Firmicutes phylum. These results underscore the importance of dysbiosis in IBD but suggest that different bacterial species contribute to the pathogenesis of UC and CD.
1,267 citations