Cited by 19Gut microbiota and healthGastrointestinal motility and disordersMicrobial Metabolites in Food Biotechnology

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In vitro microbiota model recapitulates and predicts individualised sensitivity to dietary emulsifier

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Rytter, Héloïse, Naimi, Sabrine, Wu, Gary, Lewis, Jim, Duquesnoy, Maeva, Vigué, Lucile, Tenaillon, Olivier, Belda, Eugeni, Vazquez-Gomez, Marta, Touly, Nina, Arnone, Djésia, Hao, Fuhua, Ley, Ruth E, Clément, Karine, Peyrin-Biroulet, Laurent, Patterson, Andrew D, Gewirtz, Andrew T, Chassaing, Benoit·2025·Gut

Abstract

Background: Non-absorbed dietary emulsifiers, including carboxymethylcellulose (CMC), directly disturb intestinal microbiota, thereby promoting chronic intestinal inflammation in mice. A randomised controlled-feeding study (Functional Research on Emulsifiers in Humans, FRESH) found that CMC also detrimentally impacts intestinal microbiota in some, but not all, healthy individuals. Objectives: This study aimed to establish an approach for predicting an individual’s sensitivity to dietary emulsifiers via their baseline microbiota. Design: We evaluated the ability of an in vitro microbiota model (MiniBioReactor Arrray, MBRA) to reproduce and predict an individual donor’s sensitivity to emulsifiers. Metagenomes were analysed to identify signatures of emulsifier sensitivity. Results: Exposure of human microbiotas, maintained in the MBRA, to CMC recapitulated the differential CMC sensitivity previously observed in FRESH subjects. Furthermore, select FRESH control subjects (ie, not fed CMC) had microbiotas that were highly perturbed by CMC exposure in the MBRA model. CMC-induced microbiota perturbability was associated with a baseline metagenomic signature, suggesting the possibility of using one’s metagenome to predict sensitivity to dietary emulsifiers. Transplant of human microbiotas that the MBRA model deemed CMC-sensitive, but not those deemed insensitive, into IL-10 −/− germfree mice resulted in overt colitis following CMC feeding. Conclusion: These results suggest that an individual’s sensitivity to emulsifier is a consequence of, and can thus be predicted by, examining their baseline microbiota, paving the way to microbiota-based personalised nutrition.

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Figures

Figure 1 MBRA-based microbiota modelling accurately replicates interindividual variations in microbiota composition and captures the CMC-induced microbiota perturbations. (A) Schematic outline of the experimental plan used. Faecal samples from the 16 FRESH subjects (9 participants from the control group and 7 participants from the CMC-exposed groups) were used to inoculate triplicates MBRA chambers. Microbiota were then allowed to equilibrate for 24 hours prior flow initiation. After a 3-day microbiota stabilisation phase, chambers were treated from 0 hour to 120 hours, in triplicates for each donor, with BRM medium containing CMC at 0.1% or control sterile BRM medium. At the 120 hours time point, post-treatment phase was initiated, with CMC treatment discontinued by connecting all chambers to emulsifier-free BRM sterile medium. Samples were collected longitudinally. (B) Microbiota composition was analysed by 16S rRNA gene sequencing and principal coordinates analysis (PCoA) of the Jaccard matrix combining MBRA samples at all time points was plotted, with dots coloured by patient. (C) Taxonomic analyses were computed through QIIME2 pipeline at the order level. Data are the means±SEM, with individual data points being represented (N=3). Significance was determined using Permanova analysis. (D) Longitudinal analysis of the Bray-Curtis distance in faecal sample from CMC arm of the FRESH study. Data were normalised based on day 4 distance. (E) Longitudinal analysis of the Bray-Curtis distance in MBRA samples generated with CMC participants of the FRESH study. Data were normalised with the untreated condition and time point 0 hour (poststabilisation), both defined as 1. Grey area indicates the post-treatment phase. p<0.05 determined by a two-way ANOVA corrected for multiple comparisons or mixed-effect analysis. (D) Data from Chassaing et al.17 ANOVA, analysis of variance; BRM, Bioreactor Medium; CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; MBRA, MiniBioReactor Arrray.
Figure 1 MBRA-based microbiota modelling accurately replicates interindividual variations in microbiota composition and captures the CMC-induced microbiota perturbations. (A) Schematic outline of the experimental plan used. Faecal samples from the 16 FRESH subjects (9 participants from the control group and 7 participants from the CMC-exposed groups) were used to inoculate triplicates MBRA chambers. Microbiota were then allowed to equilibrate for 24 hours prior flow initiation. After a 3-day microbiota stabilisation phase, chambers were treated from 0 hour to 120 hours, in triplicates for each donor, with BRM medium containing CMC at 0.1% or control sterile BRM medium. At the 120 hours time point, post-treatment phase was initiated, with CMC treatment discontinued by connecting all chambers to emulsifier-free BRM sterile medium. Samples were collected longitudinally. (B) Microbiota composition was analysed by 16S rRNA gene sequencing and principal coordinates analysis (PCoA) of the Jaccard matrix combining MBRA samples at all time points was plotted, with dots coloured by patient. (C) Taxonomic analyses were computed through QIIME2 pipeline at the order level. Data are the means±SEM, with individual data points being represented (N=3). Significance was determined using Permanova analysis. (D) Longitudinal analysis of the Bray-Curtis distance in faecal sample from CMC arm of the FRESH study. Data were normalised based on day 4 distance. (E) Longitudinal analysis of the Bray-Curtis distance in MBRA samples generated with CMC participants of the FRESH study. Data were normalised with the untreated condition and time point 0 hour (poststabilisation), both defined as 1. Grey area indicates the post-treatment phase. p<0.05 determined by a two-way ANOVA corrected for multiple comparisons or mixed-effect analysis. (D) Data from Chassaing et al.17 ANOVA, analysis of variance; BRM, Bioreactor Medium; CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; MBRA, MiniBioReactor Arrray.CC BY-NC · PubMed Central
Figure 2 Metagenomic markers exhibited a positive correlation with sensitivity status, facilitating the identification of new CMC-sensitive microbiotas through MBRA. (A) List of the FRESH participants used in the current study and their respective CMC-sensitivity status, identified in clinics. (B) Heatmap visualisation of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in sensitive and insensitive FRESH participants from CMC arm. (C) Heatmap visualisation of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in FRESH participants from control arm. (D) Longitudinal analysis of the Bray-Curtis distance in faecal sample from control arm of the FRESH study. Data were normalised based on day 4 distance. (E) Longitudinal analysis of the Bray-Curtis distance in MBRA samples generated with control participants of the FRESH study. Data were normalised with the untreated condition and time point 0 hour (poststabilisation), both defined as 1. Grey area indicates the post-treatment phase. p<0.05 determined by a two-way ANOVA corrected for multiple comparisons or mixed-effect analysis. (D) Data from Chassaing et al.17 ANOVA, analysis of variance; CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; MBRA, MiniBioReactor Arrray.
Figure 2 Metagenomic markers exhibited a positive correlation with sensitivity status, facilitating the identification of new CMC-sensitive microbiotas through MBRA. (A) List of the FRESH participants used in the current study and their respective CMC-sensitivity status, identified in clinics. (B) Heatmap visualisation of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in sensitive and insensitive FRESH participants from CMC arm. (C) Heatmap visualisation of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in FRESH participants from control arm. (D) Longitudinal analysis of the Bray-Curtis distance in faecal sample from control arm of the FRESH study. Data were normalised based on day 4 distance. (E) Longitudinal analysis of the Bray-Curtis distance in MBRA samples generated with control participants of the FRESH study. Data were normalised with the untreated condition and time point 0 hour (poststabilisation), both defined as 1. Grey area indicates the post-treatment phase. p<0.05 determined by a two-way ANOVA corrected for multiple comparisons or mixed-effect analysis. (D) Data from Chassaing et al.17 ANOVA, analysis of variance; CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; MBRA, MiniBioReactor Arrray.CC BY-NC · PubMed Central
Figure 3 Microbiotas from FRESH participants predicted to be CMC-sensitive conferred severe CMC-induced colitis in germfree IL10−/− recipient mice. (A) Germfree Il-10−/− mice were transplanted with faecal suspension from either CMC-predicted insensitive or CMC-predicted sensitive FRESH participants. Two weeks post microbiota stabilisation, mice were treated with either water or CMC (1% w/v) for 16 weeks. (B) Colon length, (C) histopathological scoring of the colonic mucosa, (D) representative images of colonic sections immune-stained with anti-CD68 antibody, and (E) quantification of colonic CD68+cells. (F, G) Proximal colons were fixed in Carnoy solution and subjected to immunostaining paired with fluorescent in situ hybridisation (FISH), followed by confocal microscopy analysis to determine microbiota localisation. MUC2, green; actin, purple; bacteria, red and DNA, blue. (F) Representative confocal images of microbiota encroachment. (G) Averaged distances separating the microbiota from the intestinal epithelium. Data are represented as the means±SEM. Statistical analyses were performed using a one-way ANOVA or a two-way repeated measures ANOVA or a mixed-effects model (if missing values; assuming sphericity and no correction). ANOVA was followed by a Sidak post hoc test between CMC-treated group and water-treated group for each of the microbiota used for transplantation. Significant differences were recorded as follows: *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. n=3–4. ANOVA, analysis of variance; CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans.
Figure 3 Microbiotas from FRESH participants predicted to be CMC-sensitive conferred severe CMC-induced colitis in germfree IL10−/− recipient mice. (A) Germfree Il-10−/− mice were transplanted with faecal suspension from either CMC-predicted insensitive or CMC-predicted sensitive FRESH participants. Two weeks post microbiota stabilisation, mice were treated with either water or CMC (1% w/v) for 16 weeks. (B) Colon length, (C) histopathological scoring of the colonic mucosa, (D) representative images of colonic sections immune-stained with anti-CD68 antibody, and (E) quantification of colonic CD68+cells. (F, G) Proximal colons were fixed in Carnoy solution and subjected to immunostaining paired with fluorescent in situ hybridisation (FISH), followed by confocal microscopy analysis to determine microbiota localisation. MUC2, green; actin, purple; bacteria, red and DNA, blue. (F) Representative confocal images of microbiota encroachment. (G) Averaged distances separating the microbiota from the intestinal epithelium. Data are represented as the means±SEM. Statistical analyses were performed using a one-way ANOVA or a two-way repeated measures ANOVA or a mixed-effects model (if missing values; assuming sphericity and no correction). ANOVA was followed by a Sidak post hoc test between CMC-treated group and water-treated group for each of the microbiota used for transplantation. Significant differences were recorded as follows: *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. n=3–4. ANOVA, analysis of variance; CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans.CC BY-NC · PubMed Central
Figure 4 Identification of a metagenomic signature associated with CMC-sensitivity status. (A) List of the FRESH participants used in the current study and their respective CMC-sensitivity status, identified either in clinics or using in vitro microbiota modelisation (B–D) Shotgun metagenomic approach was performed on baseline faecal samples from FRESH participants. (B) PCoA plot of the Bray-Curtis distance matrix generated on metagenomic data from FRESH study participants at the functional level using HUMAnN 3.0 pipeline and the UniRef90 database. (C) Heatmap visualisation of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in sensitive and insensitive FRESH participants. (D) Abundance of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in sensitive and insensitive FRESH participants. CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; PCOA, principal coordinates analysis.
Figure 4 Identification of a metagenomic signature associated with CMC-sensitivity status. (A) List of the FRESH participants used in the current study and their respective CMC-sensitivity status, identified either in clinics or using in vitro microbiota modelisation (B–D) Shotgun metagenomic approach was performed on baseline faecal samples from FRESH participants. (B) PCoA plot of the Bray-Curtis distance matrix generated on metagenomic data from FRESH study participants at the functional level using HUMAnN 3.0 pipeline and the UniRef90 database. (C) Heatmap visualisation of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in sensitive and insensitive FRESH participants. (D) Abundance of the MaAsLin2-identified emulsifier sensitivity marker’s abundance in sensitive and insensitive FRESH participants. CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; PCOA, principal coordinates analysis.CC BY-NC · PubMed Central
Figure 5 Presence of metagenomic markers associated to CMC-sensitivity status among other cohorts. (A) Overview of the cohorts used in the current study. After use of the FRESH cohort to identify the metagenomic signature of CMC sensitivity, the prevalence of these markers was searched across various cohorts, including healthy participants and patients. (B–D) Shotgun metagenomic approach was performed on faecal samples from Mucosa (IBD patients) and Metacardis (healthy participants and obese±T2D patients) cohorts. Data are represented as PCoA of the Euclidean distance matrix generated using the relative abundance of markers in the Mucosa (B) or (C, D) the Metacardis cohort. Dots are coloured by number of markers present (B, C) or patients health status (D). CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; IBD, inflammatory bowel disease; PCoA, principal coordinates analysis; T2D, type 2 diabetes.
Figure 5 Presence of metagenomic markers associated to CMC-sensitivity status among other cohorts. (A) Overview of the cohorts used in the current study. After use of the FRESH cohort to identify the metagenomic signature of CMC sensitivity, the prevalence of these markers was searched across various cohorts, including healthy participants and patients. (B–D) Shotgun metagenomic approach was performed on faecal samples from Mucosa (IBD patients) and Metacardis (healthy participants and obese±T2D patients) cohorts. Data are represented as PCoA of the Euclidean distance matrix generated using the relative abundance of markers in the Mucosa (B) or (C, D) the Metacardis cohort. Dots are coloured by number of markers present (B, C) or patients health status (D). CMC, carboxymethylcellulose; FRESH, Functional Research on Emulsifiers in Humans; IBD, inflammatory bowel disease; PCoA, principal coordinates analysis; T2D, type 2 diabetes.CC BY-NC · PubMed Central

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Metadata

Authors
Rytter, H., Naimi, S., Wu, G., Lewis, J., Duquesnoy, M., Vigué, L., Tenaillon, O., Belda, E., Vazquez-Gomez, M., Touly, N., Arnone, D., Hao, F., Ley, R. E., Clément, K., Peyrin-Biroulet, L., Patterson, A. D., Gewirtz, A. T., & Chassaing, B.
Affiliations
  • Centre National de la Recherche Scientifique (FR)
  • University of Pennsylvania (US)
  • Microbiome-Host Interactions, INSERM U1306, CNRS UMR6047, Institut Pasteur, Université Paris Cité, Paris, France
  • Inserm (FR)
  • Inserm, Nutrition and Obesities: Systemic Approaches Research Unit, NutriOmics, Sorbonne University, Paris, France
  • Pennsylvania State University (US)
  • Max Planck Institute for Biology (DE)
  • INFINY Institute, Nancy University Hospital, Vandœuvre-lès-Nancy, France
  • Georgia State University (US)
Venue
Gut
Publisher
BMJ
Published
2025-01-27
Volume
74
Issue
5
Pages
761-774
ISSN
  • 0017-5749 (ISSN-L)
  • 1468-3288
OpenAlex
W4406870625
Cited by
19
References
7
Citations by year
2026: 12 · 2025: 7
FWCI
5.71
Type
journal article
Language
en
Open access
Locations
  • Gut (publishedVersion, cc-by-nc)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • HAL (submittedVersion, cc-by)
Funders
  • EMULBIONT (ANR-21-CE15-0042-01)
  • Paris Région – DIM One Health-DOH 2.0
  • European Research Council
  • INSERM
  • DREAM (ANR-20-PAMR-0002)
  • the Kenneth Rainin Foundation, ANR (ANR-21-CE15-0042-01)
  • European Union (804135, ERC-2018-StG)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
  • Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
  • Health Sciences › Nursing › Nutrition and Dietetics › Microbial Metabolites in Food Biotechnology
Keywords
food emulsifiers, carboxymethyl cellulose, gut microbiota, microbiota transplantation, colitis, personalized nutrition, chronic intestinal inflammation
MeSH terms
Gastrointestinal Microbiome, Animals, Carboxymethylcellulose Sodium, Female, Humans, Male, Interleukin-10, Emulsifying Agents, Mice

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