A29 NOVEL FECAL BIOMARKERS THAT PRECEDE CLINICAL DIAGNOSIS OF ULCERATIVE COLITIS

Abstract Background Altered gut microbiota composition and function has been associated with inflammatory bowel diseases (IBD) including ulcerative colitis (UC), but causality and mechanisms remain unknown. Most studies have examined patients with active or treated disease and little is known about microbial compositional or functional changes that occur before disease onset. Aims We studied a longitudinal cohort of subjects at risk for IBD to define the fecal microbial composition and function in subjects prior to UC onset (pre-UC) and at diagnosis (post-UC), and in matched at-risk subjects that remained healthy. Methods Fecal samples were collected from healthy individuals at-risk for IBD (pre-UC; n=13) and subjects were followed longitudinally until UC diagnosis (post-UC, n=9), at which point another fecal sample was collected. Fecal samples from a cohort of matched at-risk individuals that did not develop UC were used as healthy controls (n=48). We applied 16S rRNA gene sequencing, next generation shotgun sequencing, in vitro proteolytic assays and gnotobiotic colonizations to define the microbial composition and proteolytic function in fecal samples. Results The microbiota of post-UC subjects clustered separately from pre-UC and HC subjects, based on bray-curtis and unweighted UniFrac, had reduced alpha-diversity, and had reduced abundance of Aldercreutzia compared to pre-UC and HC. In vitro functional analysis revealed increased fecal proteolytic and elastase activity in pre-UC and post-UC samples compared to HC. Metagenomics identified pathways and gene families related to protein metabolism and proteases/peptides that were significantly different between HC and pre-UC samples, suggesting a bacterial component to the pre-UC proteolytic signature. Elastase activity inversely correlated with the relative abundance of Adlercreutzia, and other potentially beneficial taxa, and directly correlated with Bacteroides vulgatus, a known proteolytic taxon. High elastase activity was confirmed in Bacteroides isolates from fecal samples. Bacterial contribution and functional significance of the proteolytic signature was investigated in germ-free adults and litters born from dams colonized with HC, pre-UC or post-UC microbiota. Mice colonized with pre-UC microbiota at adulthood or neonatally developed higher fecal proteolytic activity and an inflammatory immune tone compared with HC colonized mice. Conclusions We have identified increased fecal proteolytic activity that precedes clinical diagnosis of UC and associates with gut microbiota changes. This may constitute a non-invasive biomarker of inflammation to monitor at-risk populations that can be targeted therapeutically with anti-proteases. Funding Agencies CAG, CCC, CIHR

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A210 ADLERCREUTZIA IS DEPLETED IN UC PATIENTS, EVEN BEFORE CLINICAL DIAGNOSIS, AND INVERSELY CORRELATES WITH FECAL ELASTOLYTIC ACTIVITY

Journal of the Canadian Association of Gastroenterology ◽

10.1093/jcag/gwz047.209 ◽

2020 ◽

Vol 3 (Supplement_1) ◽

pp. 82-83

Author(s):

A Santiago Badenas ◽

J Libertucci ◽

W Turpin ◽

H J Galipeau ◽

K Croitoru ◽

...

Keyword(s):

Ulcerative Colitis ◽

At Risk ◽

Microbial Community ◽

Proteolytic Activity ◽

Clinical Diagnosis ◽

Community Analysis ◽

Microbial Community Analysis ◽

Healthy Controls ◽

Fecal Samples ◽

Elastolytic Activity

Abstract Background A combination of genetics, environmental, and immune factors contribute to the development of ulcerative colitis (UC). Host proteolytic imbalance has been reported in active UC. Preliminary results from our lab suggest microbial proteolytic activity is increased before as well as after onset of UC, and transfer of this activity to mice contributes to inflammation. Aims Our aim was to correlate the elastolytic activity of fecal samples from individuals at risk for IBD, before and after onset of ulcerative colitis, with their fecal microbiota profiles Methods We first investigated proteolytic activity in fecal samples from individuals at risk to develop UC (pre-UC, n=12) prior to disease onset and after UC diagnosis (post-UC, n=7) and matched healthy controls (n=66). Microbial community analysis was performed by sequencing the V4 region of the 16S rRNA gene region using Illumina MiSeq platform. Sequences were analyzed with QIIMEv1.9.0. We measured bacterial proteolytic activity, using a FITC-elastin assay. Results Microbial community analysis revealed that the overall diversity (both richness and evenness) in UC patients was decreased compared to healthy controls as well as pre-UC patients. The relative abundance of the genus Adlercreutzia was decreased by 3.1 fold in pre-UC patients compared to healthy controls and was further decreased in post-UC (3.8 fold). The presence of Adlercreutzia was also found to be negatively correlated (r=-0.47, p<0.0001) with elastolytic activity in stool supernatant, suggesting a possible protective role in the disease. Conclusions We found novel potentially protective bacteria, Adlercreutzia, which was depleted in UC patients, even before clinical diagnosis and correlated negatively with proinflammatory elastolytic activity described previously in IBD. The protective mechanisms are under investigation. On behalf of the CCC-GEM Project consortiumand Supported by a CCC GIA to EFV Funding Agencies CCC

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Fecal microbiota dynamics during disease activity and remission in newly diagnosed and established ulcerative colitis

Scientific Reports ◽

10.1038/s41598-021-87973-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Lena Öhman ◽

Anders Lasson ◽

Anna Strömbeck ◽

Stefan Isaksson ◽

Marcus Hesselmar ◽

...

Keyword(s):

Ulcerative Colitis ◽

Gut Microbiota ◽

Disease Activity ◽

Temporal Dynamics ◽

Fecal Microbiota ◽

Disease Stage ◽

Dietary Interventions ◽

Microbial Composition ◽

Fecal Samples ◽

Specific Species

AbstractPatients with ulcerative colitis (UC) have an altered gut microbiota composition, but the microbial relationship to disease activity needs to be further elucidated. Therefore, temporal dynamics of the fecal microbial community during remission and flare was determined. Fecal samples were collected at 2–6 time-points from UC patients during established disease (cohort EST) and at diagnosis (cohort NEW). Sampling range for cohort EST was 3–10 months and for cohort NEW 36 months. Relapses were monitored for an additional three years for cohort EST. Microbial composition was assessed by Genetic Analysis GA-map Dysbiosis Test, targeting ≥ 300 bacteria. Eighteen patients in cohort EST (8 with maintained remission and 10 experiencing a flare), provided 71 fecal samples. In cohort NEW, 13 patients provided 49 fecal samples. The microbial composition showed no clustering related to disease activity in any cohort. Microbial dissimilarity was higher between than within patients for both cohorts, irrespective of presence of a flare. Microbial stability within patients was constant over time with no major shift in overall composition nor modification in the abundance of any specific species. Microbial composition was not affected by intensified medical treatment or linked to future disease course. Thus in UC, the gut microbiota is highly stable irrespective of disease stage, disease activity or treatment escalation. This suggests that prolonged dietary interventions or repeated fecal transplantations are needed to be able to induce permanent alterations of the gut microbiota.

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Effects of Xylo-Oligosaccharide on the Gut Microbiota of Patients With Ulcerative Colitis in Clinical Remission

Frontiers in Nutrition ◽

10.3389/fnut.2021.778542 ◽

2021 ◽

Vol 8 ◽

Author(s):

Zongwei Li ◽

Zhengpeng Li ◽

Liying Zhu ◽

Ning Dai ◽

Gang Sun ◽

...

Keyword(s):

Ulcerative Colitis ◽

Gut Microbiota ◽

Healthy Volunteers ◽

Clinical Remission ◽

Principal Component ◽

Fecal Samples ◽

Linear Discriminant ◽

Wilcoxon Rank Sum Test ◽

Rdna Sequencing

Gut microbiota dysbiosis is closely associated with ulcerative colitis (UC). Prebiotic therapy is a potential approach for UC management especially remission maintaining. Xylo-oligosaccharide (XOS) is an efficient prebiotic with proven health benefits and few side effects. However, the effects of XOS on the gut microbiota of patients with UC have not been investigated previously. The aim of this study was to evaluate the prebiotic effects of XOS on the fecal microbiota of patients with UC in clinical remission using an in vitro fermentation model. Five patients with UC in clinical remission and five healthy volunteers were enrolled in this study. Fresh fecal samples of UC patients were diluted and inoculated in yeast extract, casitone and fatty acid (YCFA) medium alone or with XOS. After fermentation for 48 h, samples were collected for 16S rDNA sequencing to investigate the gut microbiota composition. Differences in the gut microbiota between healthy volunteers and UC patients in clinical remission were detected using original fecal samples. Subsequently, the differences between the YCFA medium alone or with XOS samples were analyzed to illustrate the effects of XOS on the gut microbiota of UC patients. In both principal coordinate analysis (PCoA) and principal component analysis (PCA), the fecal samples of UC patients differed from those of healthy volunteers. Linear discriminant analysis effect size (LEfSe) analysis revealed that the relative abundances of g_Roseburia and g_Lachnospiraceae_ND3007_group were higher in healthy volunteers than in UC patients, while o_Lactobacillales abundance showed the opposite trend (P < 0.05). Wilcoxon rank-sum test bar plot showed that the abundances of g_Eubacterium_halli_group and g_Lachnospiraceae_ND3007_group were higher in the healthy volunteers than in the UC patients (P < 0.05). In addition, in UC patients, the Wilcoxon rank-sum test showed that XOS fermentation promoted the growth of bacterial groups including g_Roseburia, g_Bifidobacterium, and g_Lactobacillus, which is beneficial for recovery of intestinal diseases. These results suggest that XOS can relieve dysbiosis in the feces of UC patients in clinical remission and thus represent a potential prebiotic material for maintaining remission.

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Long term exposure of human gut microbiota with high and low emulsifier sensitivity to soy lecithin in M-SHIME model.

10.1101/2021.12.16.472798 ◽

2021 ◽

Author(s):

Lisa Miclotte ◽

Ellen De Paepe ◽

Qiqiong Li ◽

Andreja Rajkovic ◽

John Van Camp ◽

...

Keyword(s):

Gut Microbiota ◽

Day Treatment ◽

Treatment Phase ◽

Microbial Composition ◽

Soy Lecithin ◽

Potential Health ◽

And Function ◽

The Impact

In the context of the potential health hazards related to food processing, dietary emulsifiers have been shown to alter the structure and function of the gut microbial community, both in vivo and in vitro. In mouse models, these emulsifier exposed gut microbiota were shown to contribute to gut inflammation. Several knowledge gaps remain to be addressed though. As such, the impact from a longer timeframe of exposure on the gut microbiota is not known and interindividual variability in microbiome response needs to be measured. To answer these research questions, in this study the faecal microbiota from two individuals, previously selected for high and low emulsifier sensitivity, were exposed to two concentrations of soy lecithin during a 7 day treatment phase in the dynamic mucosal simulator of the human intestinal microbial ecosystem (M-SHIME). The results showed mild effects from soy lecithin on the composition and functionality of these microbial communities, which depended on the original microbial composition. The effects also mostly levelled off after 3 days of exposure. The emulsifier sensitivity for which the microbiota were selected, was preserved. Some potentially concerning effects were also registered: butyrate levels, positively correlating with Faecalibacterium abundance, were lowered by soy lecithin. Also the abundance of the beneficial Bifidobacterium genus was lowered, while the abundance of the notorious unclassified Enterobacteriaceae was increased. Within the family of the unclassified Lachnospiraceae, several genera were either suppressed or stimulated. The effects that these microbial alterations would have on a living host is not yet certain, especially given the fact that large fractions of soy lecithins constituents can be absorbed. Nevertheless, choline and phosphatidylcholine, both primary and absorbable constituents of soy lecithin, have recently been linked to cardiovascular disease via the generation of TMA by the gut microbiota. Further studies that validate our findings and link them to potential health outcomes are thus justified.

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Fecal Microbiota Dynamics During Disease Activity and Remission in Newly Diagnosed and Established Ulcerative Colitis

10.21203/rs.3.rs-134029/v1 ◽

2021 ◽

Author(s):

Lena Öhman ◽

Anders Lasson ◽

Anna Strömbeck ◽

Stefan Isaksson ◽

Marcus Hesselmar ◽

...

Keyword(s):

Ulcerative Colitis ◽

Gut Microbiota ◽

Disease Activity ◽

Temporal Dynamics ◽

Fecal Microbiota ◽

Disease Stage ◽

Dietary Interventions ◽

Microbial Composition ◽

Fecal Samples ◽

Specific Species

Abstract Patients with ulcerative colitis (UC) have an altered gut microbiota composition, but the microbial relationship to disease activity needs to be further elucidated. Therefore, temporal dynamics of the fecal microbial community during remission and flare was determined. Fecal samples were collected at 2–6 time-points from UC patients during established disease (cohort EST) and at diagnosis (cohort NEW). Sampling range for cohort EST was 3–10 months and for cohort NEW 36 months. Relapses were monitored for an additional three years for cohort EST. Microbial composition was assessed by Genetic Analysis GA-map™ Dysbiosis test, targeting ≥ 300 bacteria. Eighteen patients in cohort EST (8 with maintained remission and 10 experiencing a flare), provided 71 fecal samples. In cohort NEW, 13 patients provided 49 fecal samples. The microbial composition showed no clustering related to disease activity in any cohort. Microbial dissimilarity was higher between than within patients for both cohorts, irrespective of presence of a flare. Microbial stability within patients was constant over time with no major shift in overall composition nor modification in the abundance of any specific species. Microbial composition was not affected by intensified medical treatment or linked to future disease course. Thus in UC, the gut microbiota is highly stable irrespective of disease stage, disease activity or treatment escalation. This suggests that prolonged dietary interventions or repeated fecal transplantations are needed to be able to induce permanent alterations of the gut microbiota.

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A35 MICROBIAL PROTEOLYTIC SIGNATURE IN ULCERATIVE COLITIS INDUCES AN INFLAMMATORY SIGNATURE IN MICROBIOTA-HUMANIZED MICE

Journal of the Canadian Association of Gastroenterology ◽

10.1093/jcag/gwz047.034 ◽

2020 ◽

Vol 3 (Supplement_1) ◽

pp. 42-43

Author(s):

H J Galipeau ◽

W Turpin ◽

A Caminero Fernandez ◽

A Santiago ◽

J Libertucci ◽

...

Keyword(s):

Ulcerative Colitis ◽

At Risk ◽

Proteolytic Activity ◽

Intestinal Microbiota ◽

Inflammatory Responses ◽

Critical Role ◽

Low Grade ◽

Polymorphonuclear Cells ◽

Fecal Samples ◽

Patients At Risk

Abstract Background Altered gut microbiota composition has been associated with inflammatory bowel diseases (IBD) including ulcerative colitis (UC), but causality and bacterially-driven mechanisms, are unclear. Proteases within the gastrointestinal tract play a critical role in maintaining homeostasis and are tightly regulated by anti-proteases. Host-derived proteolytic imbalances have been described in IBD, including UC, however, the role of intestinal microbiota as a source of proteases and anti-proteases has largely been ignored. Aims To study microbial proteolytic activity and intestinal microbiota profiles in a cohort of individuals at-risk for IBD, and in those individuals that develop UC at follow-up. Methods Fecal samples were collected from healthy individuals at-risk for IBD and who went on to develop UC (pre-UC; n=14) and again after UC diagnosis (post-UC, n=10). Fecal samples from matched at-risk individuals that did not develop UC were used as healthy controls (n=52). Overall fecal proteolytic and elastolytic activity was measured. We performed metagenomics sequencing in 4 UC subjects (pre and post) and 4 matched HC using Illumina Hi-Seq from stool DNA. To investigate bacterial origin and functional significance, pregnant germ-free (GF) mice were colonized with a fecal sample from a selected UC subject (pre and post) and a matched HC. Naturally colonized litters were followed for 12 weeks, after which proteolytic activities and signs of inflammation were measured. Results Fecal proteolytic and elastase activity was increased in pre- and post-UC samples compared to HCs. Metagenomics revealed over 20k genes were significantly different between HC and pre-UC samples, and of these, 440 related to proteases and peptidases. Increased fecal proteolytic activity, higher lipocalin levels, and increased colonic polymorphonuclear cells in colonic H&E sections was observed in pre- and post-UC colonized mice compared to HC colonized mice. Mice colonized with pre-UC microbiota showed increased mRNA expression of genes linked to immunological disease, antimicrobial and inflammatory responses (ie. Tlr2, Tlr5, Nod2, and Il1b) as compared to HC colonized mice. Conclusions These results suggest increased fecal proteolytic activity is observed prior to the onset and clinical diagnosis of UC in patients at-risk for IBD, and upon transfer to mice born from colonized GF dams, low-grade inflammation develops. These pathways could be developed as novel non-invasive biomarkers to monitor at-risk populations. Submitted on behalf of the CCC-GEM Project consortium. Supported by CCC GIA to EF Verdu Funding Agencies CCC

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Preservation of Human Gut Microbiota Inoculums for In Vitro Fermentations Studies

Fermentation ◽

10.3390/fermentation7010014 ◽

2021 ◽

Vol 7 (1) ◽

pp. 14

Author(s):

Nelson Mota de Carvalho ◽

Diana Luazi Oliveira ◽

Mayra Anton Dib Saleh ◽

Manuela Pintado ◽

Ana Raquel Madureira

Keyword(s):

Gut Microbiota ◽

Metabolic Profile ◽

Bacterial Count ◽

Glycerol Solution ◽

Metabolic Profiles ◽

Human Gut ◽

Colonic Fermentation ◽

In Vitro Fermentation ◽

Fecal Samples

The use of fecal inoculums for in vitro fermentation models requires a viable gut microbiota, capable of fermenting the unabsorbed nutrients. Fresh samples from human donors are used; however, the availability of fresh fecal inoculum and its inherent variability is often a problem. This study aimed to optimize a method of preserving pooled human fecal samples for in vitro fermentation studies. Different conditions and times of storage at −20 °C were tested. In vitro fermentation experiments were carried out for both fresh and frozen inoculums, and the metabolic profile compared. In comparison with the fresh, the inoculum frozen in a PBS and 30% glycerol solution, had a significantly lower (p < 0.05) bacterial count (<1 log CFU/mL). However, no significant differences (p < 0.05) were found between the metabolic profiles after 48 h. Hence, a PBS and 30% glycerol solution can be used to maintain the gut microbiota viability during storage at −20 °C for at least 3 months, without interfering with the normal course of colonic fermentation.

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Multiplatform Physiologic and Metabolic Phenotyping Reveals Microbial Toxicity

mSystems ◽

10.1128/msystems.00123-18 ◽

2018 ◽

Vol 3 (6) ◽

Cited By ~ 2

Author(s):

Jingwei Cai ◽

Robert G. Nichols ◽

Imhoi Koo ◽

Zachary A. Kalikow ◽

Limin Zhang ◽

...

Keyword(s):

Mass Spectrometry ◽

Amino Acids ◽

Flow Cytometry ◽

Free Radical ◽

Gut Microbiota ◽

Structure And Function ◽

Metabolic Phenotyping ◽

And Function

ABSTRACTThe gut microbiota is susceptible to modulation by environmental stimuli and therefore can serve as a biological sensor. Recent evidence suggests that xenobiotics can disrupt the interaction between the microbiota and host. Here, we describe an approach that combinesin vitromicrobial incubation (isolated cecal contents from mice), flow cytometry, and mass spectrometry- and1H nuclear magnetic resonance (NMR)-based metabolomics to evaluate xenobiotic-induced microbial toxicity. Tempol, a stabilized free radical scavenger known to remodel the microbial community structure and functionin vivo, was studied to assess its direct effect on the gut microbiota. The microbiota was isolated from mouse cecum and was exposed to tempol for 4 h under strict anaerobic conditions. The flow cytometry data suggested that short-term tempol exposure to the microbiota is associated with disrupted membrane physiology as well as compromised metabolic activity. Mass spectrometry and NMR metabolomics revealed that tempol exposure significantly disrupted microbial metabolic activity, specifically indicated by changes in short-chain fatty acids, branched-chain amino acids, amino acids, nucleotides, glucose, and oligosaccharides. In addition, a mouse study with tempol (5 days gavage) showed similar microbial physiologic and metabolic changes, indicating that thein vitroapproach reflectedin vivoconditions. Our results, through evaluation of microbial viability, physiology, and metabolism and a comparison ofin vitroandin vivoexposures with tempol, suggest that physiologic and metabolic phenotyping can provide unique insight into gut microbiota toxicity.IMPORTANCEThe gut microbiota is modulated physiologically, compositionally, and metabolically by xenobiotics, potentially causing metabolic consequences to the host. We recently reported that tempol, a stabilized free radical nitroxide, can exert beneficial effects on the host through modulation of the microbiome community structure and function. Here, we investigated a multiplatform phenotyping approach that combines high-throughput global metabolomics with flow cytometry to evaluate the direct effect of tempol on the microbiota. This approach may be useful in deciphering how other xenobiotics directly influence the microbiota.

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Comparative Analysis of the Gut Microbiota of Adult Mosquitoes From Eight Locations in Hainan, China

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2020.596750 ◽

2020 ◽

Vol 10 ◽

Author(s):

Xun Kang ◽

Yanhong Wang ◽

Siping Li ◽

Xiaomei Sun ◽

Xiangyang Lu ◽

...

Keyword(s):

Gut Microbiota ◽

Disease Control ◽

Bacterial Communities ◽

Mosquito Species ◽

Microbial Community Composition ◽

Variable Region ◽

Rrna Gene ◽

Microbial Composition ◽

Quality Filtering ◽

And Function

The midgut microbial community composition, structure, and function of field-collected mosquitoes may provide a way to exploit microbial function for mosquito-borne disease control. However, it is unclear how adult mosquitoes acquire their microbiome, how the microbiome affects life history traits and how the microbiome influences community structure. We analyzed the composition of 501 midgut bacterial communities from field-collected adult female mosquitoes, including Aedes albopictus, Aedes galloisi, Culex pallidothorax, Culex pipiens, Culex gelidus, and Armigeres subalbatus, across eight habitats using the HiSeq 4000 system and the V3−V4 hyper-variable region of 16S rRNA gene. After quality filtering and rarefaction, a total of 1421 operational taxonomic units, belonging to 29 phyla, 44 families, and 43 genera were identified. Proteobacteria (75.67%) were the most common phylum, followed by Firmicutes (10.38%), Bacteroidetes (6.87%), Thermi (4.60%), and Actinobacteria (1.58%). The genera Rickettsiaceae (33.00%), Enterobacteriaceae (20.27%), Enterococcaceae (7.49%), Aeromonadaceae (7.00%), Thermaceae (4.52%), and Moraxellaceae (4.31%) were dominant in the samples analyzed and accounted for 76.59% of the total genera. We characterized the midgut bacterial communities of six mosquito species in Hainan province, China. The gut bacterial communities were different in composition and abundance, among locations, for all mosquito species. There were significant differences in the gut microbial composition between some species and substantial variation in the gut microbiota between individuals of the same mosquito species. There was a marked variation in different mosquito gut microbiota within the same location. These results might be useful in the identification of microbial communities that could be exploited for disease control.

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Role of Biological Sex in the Cardiovascular-Gut Microbiome Axis

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2021.759735 ◽

2022 ◽

Vol 8 ◽

Author(s):

Shuangyue Li ◽

Georgios Kararigas

Keyword(s):

Gut Microbiota ◽

Gut Microbiome ◽

Microbial Composition ◽

Biological Sex ◽

Technological Advances ◽

Host Health ◽

Health And Disease ◽

And Function ◽

Insight Into

There has been a recent, unprecedented interest in the role of gut microbiota in host health and disease. Technological advances have dramatically expanded our knowledge of the gut microbiome. Increasing evidence has indicated a strong link between gut microbiota and the development of cardiovascular diseases (CVD). In the present article, we discuss the contribution of gut microbiota in the development and progression of CVD. We further discuss how the gut microbiome may differ between the sexes and how it may be influenced by sex hormones. We put forward that regulation of microbial composition and function by sex might lead to sex-biased disease susceptibility, thereby offering a mechanistic insight into sex differences in CVD. A better understanding of this could identify novel targets, ultimately contributing to the development of innovative preventive, diagnostic and therapeutic strategies for men and women.

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