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Cited by 123Gastrointestinal motility and disordersGut microbiota and healthMicroscopic Colitis

Intestinal microbiota and immune function in the pathogenesis of irritable bowel syndrome

Open access
Ringel, Yehuda, Maharshak, Nitsan·2013·American Journal of Physiology-Gastrointestinal and Liver Physiology
DOI 10.1152/ajpgi.00207.2012PMC PMC3798736
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Abstract

The pathophysiology of irritable bowel syndrome (IBS) is believed to involve alterations in the brain-gut axis; however, the etiological triggers and mechanisms by which these changes lead to symptoms of IBS remain poorly understood. Although IBS is often considered a condition without an identified “organic” etiology, emerging evidence suggests that alterations in the gastrointestinal microbiota and altered immune function may play a role in the pathogenesis of the disorder. These recent data suggest a plausible model in which changes in the intestinal microbiota and activation of the enteric immune system may impinge upon the brain-gut axis, causing the alterations in gastrointestinal function and the clinical symptoms observed in patients with IBS. This review summarizes the current evidence for altered intestinal microbiota and immune function in IBS. It discusses the potential etiological role of these factors, suggests an updated conceptual model for the pathogenesis of the disorder, and identifies areas for future research.

AI snapshot

Written from the paper’s full text.

TL;DR

This narrative review proposes that altered intestinal microbiota and dysregulated enteric immune function interact with the brain-gut axis to contribute to irritable bowel syndrome (IBS) pathogenesis. It summarizes evidence from animal models, human microbiota studies, immune profiling, genetic associations, and treatment trials, while noting that causation and mechanisms remain unresolved.

Key findings

  • Postinfectious IBS occurs in ∼10% of patients after acute gastroenteritis, and acute gastroenteritis increases the odds of developing IBS six- to sevenfold.
  • A meta-analysis of hydrogen breath testing reported a pooled SIBO prevalence of 54–64% in IBS patients, but individual study estimates ranged from 10% to 84%, reflecting diagnostic limitations.
  • IBS patients show evidence of low-grade immune activation, including increased activated mast cells, T cells, and altered cytokines; anti-flagellin antibodies were found in almost 30% of IBS patients, mostly PI-IBS, versus only 7% of healthy controls.
  • Microbiota-targeted treatments show some benefit: the largest reported probiotic trial included 362 patients and found Bifidobacterium infantis 35624 improved IBS composite score and individual symptoms such as pain and bloating, though effects were modest; antibiotics are not FDA-approved for IBS.

Methods

  • Narrative review of current evidence on intestinal microbiota, immune function, and the brain-gut axis in IBS; no primary data collection or systematic review methodology is described.
  • Synthesizes animal studies, human observational studies, molecular microbiota studies, immune/genetic studies, meta-analyses, and clinical trials.
  • Main analysis is conceptual synthesis, culminating in an updated model in which environmental factors affect microbiota and enteric immunity, which interact with the brain-gut axis to alter GI function and symptoms.

Limitations

  • The paper states that SIBO diagnosis is limited by lack of standardization of hydrogen breath testing and that lactulose HBT may reflect small bowel transit rather than true SIBO.
  • The paper states that most microbiota studies were done at a single time point, leaving unclear whether observed alterations are cause or consequence and how they correlate with symptoms over time.
  • The paper notes inconsistent findings for immune cell populations and cytokines in IBS, limited data on microbiota-immune interactions in IBS, and no clear guidelines for probiotics, prebiotics, or diets; evident from the text, this is a narrative review without a described systematic search strategy.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1152/ajpgi.00207.2012

Cites

204 of 204 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 304 cited sources checked · 0 supported · 0 flagged

  • Interpretationreasoning
    § Abstract

    In patients with postinfectious IBS, the condition persists long after the initial infection has cleared.

    “The extended duration of IBS symptoms in these patients indicates that the condition persists long after the initial infection has cleared.”
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  • Premisecitation
    § Abstract

    Using the historical definition of SIBO as at least 10^5 cfu/ml, bacterial cultures of aspirates from IBS patients compared with healthy volunteers showed no statistically significant differences in the incidence of SIBO.

    “Using this definition, a study of bacterial cultures of aspirates from patients with IBS compared with cultures from healthy volunteers showed no statistically significant differences in the incidence of SIBO (141).”
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    § Abstract

    Limited data suggest differences in mucosa-associated microbiota in patients with IBS.

    “Limited data also suggest differences in mucosa-associated microbiota (32, 33, 86, 129), reduced stability over time (106, 107), rDNA, and differences between IBS subtypes (81, 104, 129, 142).”
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    § Abstract

    Acute gastroenteritis increases the odds of developing IBS six- to sevenfold.

    “PI-IBS occurs in ∼10% of patients with acute gastroenteritis, and acute gastroenteritis increases the odds of developing IBS six- to sevenfold (76, 157, 172).”
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  • Interpretationcitation
    § Abstract

    Lactulose hydrogen breath testing results may reflect changes in small bowel transit time rather than the true presence of SIBO.

    “However, the wide range of prevalence of SIBO reported in individual studies [from 10% (186) to 84% (130)] reflects the lack of standardization of HBT and the possibility that lactulose HBT results may reflect changes in small bowel transit time rather than the true presence of SIBO (194).”
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    Interpretationcitation
    § Abstract

    Data from meta-analyses indicating increased prevalence of SIBO in IBS, symptom overlap between the two conditions, and improvement of symptoms with antibiotic treatment support the hypothesis that alterations in the intestinal microbiota may have a role in the pathogenesis of IBS, at least in some patients.

    “Nonetheless, the data from meta-analyses indicating increased prevalence of SIBO in IBS, the symptom overlap between the two conditions, and the improvement of symptoms with antibiotic treatment (47, 49, 59, 103, 131, 135, 136, 193) further support the hypothesis that alterations in the intestinal microbiota may have a role in the pathogenesis of IBS, at least in some patients.”
    Quote in the paperSubstantial claim0 of 8 sources checked
    • cites [47] Cuoco L, 2006, Minerva Gastroenterol Dietol

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    • cites [103] Majewski M, 2007, Adv Med Sci

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    • cites [136] Pimentel M, 2003, Am J Gastroenterol

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    Premisecitation
    § Abstract

    When a lower cutoff concentration of at least 10^4 cfu/ml was used, significant differences were observed, suggesting increased numbers of bacteria in the small intestine of patients with IBS.

    “However, when a lower cutoff concentration of ≥104 cfu/ml was used, significant differences were observed, suggesting increased numbers of bacteria in the small intestine of patients with IBS.”
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    § Abstract

    Exposure of rats to L. reuteri or L. acidophilus NCFM reduces their pain response to balloon distension, through targeting ion channels in the enteric nervous system or increasing expression of μ-opioid and cannabinoid receptors in intestinal epithelial cells.

    “In addition, exposure of rats to L. reuteri (83) or L. acidophilus NCFM (151) reduce their pain response to balloon distension, through targeting ion channels in the enteric nervous system (83, 91) or increasing the expression of μ-opioid and cannabinoid receptors in intestinal epithelial cells (151).”
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    § Abstract

    In the recent small study, the differences in primary bile acid correlated with stool consistency and frequency and were associated with decreased levels of the Clostridium leptum group.

    “Interestingly, these differences correlated with stool consistency and frequency and were associated with decreased levels of the Clostridium leptum group, which contains many of the bacteria that can transform primary into secondary bile acid.”
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    • Rests on an assumption: Intestinal microbiota are directly responsible for the transformation of primary into secondary bile acid.

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    Premisecitation
    § Abstract

    The gut microbiota have an important role in promoting the development, maintenance, and function of the intestinal barrier by increasing IgA production and mucin expression, preventing intestinal epithelial cell apoptosis, inhibiting colonization by enteric pathogens, and promoting physiological immune responses.

    “The gut microbiota have an important role in promoting the development, maintenance, and function of the intestinal barrier by increasing IgA production and mucin expression, preventing intestinal epithelial cell apoptosis, inhibiting colonization by enteric pathogens, and promoting physiological immune responses (113, 173, 178).”
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    Interpretationcitation
    § Abstract

    Intestinal microbiota may affect gut motility and pain perception.

    “Intestinal microbiota may affect gut motility and pain perception.”
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    § Abstract

    In the antibiotic-perturbation mouse model, treatment with Lactobacillus ameliorated inflammatory indexes in the gut wall and reduced the antibiotic-induced visceromotor response.

    “Interestingly, in this model, treatment of mice with Lactobacillus ameliorated inflammatory indexes in the gut wall and reduced the antibiotic-induced visceromotor response.”
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    § Abstract

    Increased levels of CD4+ T helper cells were observed in the colon of patients with IBS in one study but not in another.

    “Similarly, increased levels of CD4+ T helper cells were observed in the colon of patients with IBS in one study (46) but not in another (123), leaving the role for this T cell subtype in IBS unclear.”
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    § Abstract

    Activated mast cells were found in close proximity to enteric nerves and correlated with abdominal pain/discomfort in patients with IBS.

    “Interestingly, the activated mast cells were found to be in close proximity to enteric nerves and correlated with abdominal pain/discomfort (11).”
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    § Abstract

    Some studies demonstrated an increase in activated mast cells in biopsies from specific regions of the GI tract (cecum and terminal ileum) but not from other regions, whereas other studies found activated mast cells in the descending colon.

    “Notably, some studies demonstrated an increase in activated mast cells in biopsies from specific regions of the GI tract (i.e., cecum and terminal ileum) but not from other regions (e.g., ascending colon, descending colon, rectum) (89, 121, 187), whereas other studies have found activated mast cells in the descending colon (11, 13).”
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    § Abstract

    Concentrations of cytotoxic CD8+ T cells may be elevated in the lamina propria of the colon of patients with IBS or PI-IBS, although this finding was disputed by others.

    “Concentrations of cytotoxic CD8+ T cells, which comprise most of the intraepithelial T cell population (126) may also be elevated in the lamina propria of the colon of patients with IBS (46, 123) or PI-IBS (89) although this finding was disputed by others (36).”
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    § Abstract

    Increases in the secretion of TNF-α following lipopolysaccharide stimulation of peripheral blood mononuclear cells and of IL-1β following T-cell anti-CD3/CD28 antibody stimulation were significantly associated with anxiety and bowel habit dissatisfaction and overall IBS symptoms, respectively.

    “Furthermore, increases in the secretion of TNF-α following LPS stimulation of PBMCs and of IL-1β following T-cell anti-CD3/CD28 antibodies stimulation were significantly associated with anxiety (98) and bowel habit dissatisfaction and overall IBS symptoms (122), respectively.”
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    § Abstract

    Levels of MAdCAM-1 are elevated on colonic endothelial cells in IBS, creating an environment for enhanced recruitment of CD4+ and CD8+ T cells to the intestines.

    “Levels of MAdCAM-1, the ligand of integrin β7, are also elevated on colonic endothelial cells (123), creating an environment for enhanced recruitment of CD4+ and CD8+ T cells to the intestines of patients with IBS.”
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    § Abstract

    Patients with IBS may have increased expression of IgG and the costimulatory molecules CD80 and CD86 on B cells and an increased frequency of peripheral blood IgG+CD80+ and IgG+CD86+ B cells.

    “In addition, patients with IBS may have increased expression of IgG and the costimulatory molecules CD80 and CD86 on B cells and an increased frequency of peripheral blood IgG+CD80+ and IgG+CD86+ B cells (124).”
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    § Abstract

    The majority of IBS patients believe that their IBS symptoms are initiated or worsened by certain foods, and many report intolerance to a variety of foods.

    “The majority of IBS patients believe that their IBS symptoms are initiated or worsened by certain foods and many of them report intolerance (i.e., hypersensitivity) to a variety of foods (68).”
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    § Abstract

    B cells from patients with IBS had an impaired ability to upregulate CD80 in response to in vitro lipopolysaccharide stimulation, suggesting that B cells from patients with IBS may have an altered ability to costimulate and regulate T cells.

    “Furthermore, B cells from patients with IBS had an impaired ability to upregulate CD80 in response to in vitro lipopolysaccharide (LPS) stimulation, suggesting that B cells from patients with IBS may have an altered ability to costimulate and regulate T cells.”
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    Interpretationcitation
    § Abstract

    Overall, alterations in cytokine secretion by stimulated peripheral blood cells appear to favor an activated immune state and an altered immune response shifted toward a T-helper 2 phenotype in IBS patients.

    “Overall, it seems that alterations in cytokine secretion by stimulated peripheral blood cells appear to favor an activated immune state (98, 122), and an altered immune response shifted toward a T-helper 2 phenotype(90) in IBS patients.”
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    § Abstract

    A single study reported reduced levels of IgA+ B cells in the ascending but not sigmoid colon of IBS patients compared with controls, whereas levels of IgG+, IgM+, and IgE+ B cells in both the ascending and sigmoid colon were normal.

    “Although no differences in total B cell numbers were observed in the colons of IBS patients (46), a single study reported reduced levels of IgA+ B cells in the ascending but not sigmoid colon compared with controls, whereas levels of IgG+, IgM+, and IgE+ B cells in both the ascending and sigmoid colon were normal (62).”
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    § Abstract

    The prevalence of specific polymorphisms in the IL-10 gene in patients with IBS is not consistent across studies and may reflect the variety of ethnic groups in which these studies were conducted.

    “However, the prevalence of specific polymorphisms in the IL-10 gene in patients with IBS are not consistent across studies and may reflect the variety of ethnic groups in which these studies were conducted (16).”
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    § Abstract

    In the Macsharry study, a decreased level of mRNA encoding the anti-inflammatory IL-10 gene was observed, as well as an altered IL-10:IL-12 ratio in colonic biopsies from patients with IBS compared with controls.

    “However, in this study a decreased level of mRNA encoding the anti-inflammatory IL-10 gene was observed, as well as an altered IL-10:IL-12 ratio in colonic biopsies from patients with IBS compared with controls, supporting the hypothesis that patients with IBS have a dysfunctional immunological response in the mucosa.”
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    § Abstract

    In one study, levels of TNF-α were elevated, but levels of IL-6 and interferon-γ were decreased in the mucosa of patients with IBS compared with controls.

    “Results from examination of cytokine protein levels have been conflicting. In one study, levels of TNF-α were elevated, but levels of IL-6 and interferon-γ were decreased in mucosa of patients with IBS compared with controls (41).”
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    Premisecitation
    § Abstract

    The effects of the intestinal microbiota on the development, function, and homeostasis of the enteric immune system are well documented.

    “The effects of the intestinal microbiota on the development, function, and homeostasis of the enteric immune system are well documented (5, 158).”
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    § Abstract

    Treatments targeting the CNS, such as antidepressants and psychological interventions, can reduce intestinal sensation/sensitivity and improve GI symptoms in patients with IBS.

    “Furthermore, treatments targeting the CNS, such as antidepressants and psychological interventions, can reduce intestinal sensation/sensitivity and improve GI symptoms in patients with IBS (21, 111, 150, 165).”
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    Interpretationreasoning
    § Abstract

    Proinflammatory cytokines (e.g., IL-1β, IL-6, and TNF-α) may interact with the brain-gut axis at different levels, modulate its function, and lead to altered visceral and motility function in patients with IBS.

    “Thus proinflammatory cytokines (e.g., IL-1β, IL-6, and TNF-α) may interact with the brain-gut axis at different levels, modulate its function, and lead to altered visceral and motility function in patients with IBS (Fig. 1).”
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    § Abstract

    Physical and psychological stress, cognition, and early life experience can affect intestinal sensory perception.

    “For example, it has been shown that physical and psychological stress (112), cognition (e.g., attention vs. distraction to aversive stimulus) (55), and early life experience (e.g., sexual and physical abuse) (39, 149) can affect intestinal sensory perception.”
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    § Abstract

    In IBS, there is increased infiltration of mast cells in the colonic mucosa in close proximity to enteric nerve fibers and an increased number of sensory nerve fibers surrounding the mast cells.

    “At the peripheral level, the close interaction between the immune system and the ENS in IBS is demonstrated by the increased infiltration of mast cells in the colonic mucosa in close proximity to enteric nerve fibers and by the increased number of sensory nerve fibers surrounding the mast cells (2, 11, 13).”
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    § Abstract

    Few studies demonstrated increased peripheral blood basophil activation following stimulation with food antigens and elevated levels of fecal tryptase and eosinophil cationic protein in patients with IBS and food hypersensitivity.

    “In addition, few studies demonstrated increased peripheral blood basophil activation following stimulation with food antigens (30) and elevated levels of fecal tryptase and eosinophil cationic protein (31) in patients with IBS and food hypersensitivity, thus further suggesting possible inflammatory and altered immune etiology.”
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    § Abstract

    AVP and CRH, by stimulating ACTH secretion, may affect the autonomic nervous system and colonic sensorimotor functions.

    “AVP and CRH, by stimulating ACTH secretion, may affect the autonomic nervous system (38) and colonic sensorimotor functions (125, 152).”
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    § Abstract

    Psychosocial stressors can change the composition of the intestinal microbiota and affect the brain-gut axis function.

    “Similarly, psychosocial stressors can change the composition of the intestinal microbiota and affect the brain-gut axis function (6, 7, 119).”
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    § Abstract

    Several studies have documented IgG-mediated food hypersensitivity and demonstrated that food-elimination diets based on IgG antibodies to specific food items improved IBS symptoms.

    “However, several studies have documented IgG-mediated food hypersensitivity and demonstrated that food-elimination diets based on IgG antibodies to specific food items improved IBS symptoms (4, 195, 196), perhaps through amelioration of the immune response.”
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    § Abstract

    In the periphery, intestinal microbiota can affect the ENS directly via release of bacterial substances or metabolites, or indirectly by inducing the release of host-derived immune mediators that in turn impact the ENS.

    “In the periphery, intestinal microbiota can affect the ENS directly via release of bacterial substances or metabolites, or indirectly by inducing the release of host-derived immune mediators that in turn impact the ENS (10, 155).”
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    Premisecitation
    § Abstract

    Enteric microbiota are crucial to the host in numerous aspects including maturation of the systemic and enteric immune response, maintenance of the mucosal barrier function, digestion of food, metabolism, and more.

    “Enteric microbiota are crucial to the host in numerous aspects including maturation of the systemic and enteric immune response, maintenance of the mucosal barrier function, digestion of food, metabolism, and more (for review, see Ref. 78).”
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    § Abstract

    Rats exposed to chronic stress exhibited activation of the HPA axis, intestinal mucosal inflammation, increased epithelial permeability, and colonic hyperalgesia.

    “For example, rats exposed to chronic stress exhibited activation of the hypothalamic-pituitary-adrenal (HPA) axis, intestinal mucosal inflammation, increased epithelial permeability, and colonic hyperalgesia (183).”
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    § Abstract

    Prebiotics and dietary manipulation have shown benefit in the treatment of IBS.

    “Other approaches targeting the intestinal microbiota that have shown benefit in the treatment of IBS include prebiotics (163) and dietary manipulation (127).”
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    § Abstract

    The effects of Bifidobacterium infantis 35624 over placebo were modest but significant.

    “Although the effects were modest, they were significant.”
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    Premisecitation
    § Abstract

    A small, double-blind, randomized study of 20 IBS patients showed that mesalamine 2.4 g/day for 8 wk failed to show improvement in IBS symptoms despite a reduction in the number of total immune cells in colonic biopsies and improvement in general well-being.

    “A small, double-blind, randomized study of 20 IBS patients showed that mesalamine 2.4 g/day for 8 wk failed to show improvement in IBS symptoms despite a reduction in the number of total immune cells in colonic biopsies and improvement in general well-being (45, 177).”
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    § Abstract

    Mesalamine 3.2 g/day for 12 wk and prednisolone 30 mg/day for 3 wk were not effective in improving GI symptoms in patients with PI-IBS.

    “Similarly, mesalamine 3.2 g/day for 12 wk (168) and prednisolone 30 mg/day for 3 wk (52) were not effective in improving the GI symptoms in patients with PI-IBS.”
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    § Abstract

    Stress-induced intestinal microbial changes are associated with altered immune response and increased susceptibility to an enteric pathogen in animal studies.

    “and the recent animal studies showing that stress-induced intestinal microbial changes are associated with altered immune response (6) and increased susceptibility to an enteric pathogen (183).”
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  • The paper relies on this without support.

    The etiological triggers and mechanisms by which brain-gut axis changes lead to symptoms of IBS remain poorly understood.

    “The pathophysiology of irritable bowel syndrome (IBS) is believed to involve alterations in the brain-gut axis; however, the etiological triggers and mechanisms by which these changes lead to symptoms of IBS remain poorly understood.”

  • The paper relies on this without support.

    Intestinal microbiota are directly responsible for the transformation of primary into secondary bile acid.

    “Since the intestinal microbiota are directly responsible for the transformation of primary into secondary bile acid it is tempting to hypothesize that the intestinal dysbiosis observed in patients with IBS can affect intestinal motility and lead to IBS symptoms through its effect(s) on bile acid metabolism.”

  • The paper relies on this without support.

    There are limited data on the interactions between the intestinal microbiota and the enteric immune system in IBS.

    “Although evidence is rapidly accumulating that dysregulated immune responses to normal and “dysbiotic” enteric microbiota contribute to the pathogenesis of IBD (105), there are limited data on the interactions between the intestinal microbiota and the enteric immune system in IBS.”

  • The paper relies on this without support.

    The connection between altered intestinal immune function and abnormal brain-gut axis in patients with IBS remains unclear.

    “The connection between altered intestinal immune function and abnormal brain-gut axis in patients with IBS remains unclear.”

  • The paper relies on this without support.

    Antibiotics are not FDA-approved medications for treatment of IBS, and there are no clear guidelines for the use of probiotics, prebiotics, and diets in this disorder.

    “Currently, despite the demonstrated efficacy in subgroups of patients with IBS, antibiotics are not FDA-approved medications for treatment of IBS, and there are no clear guidelines for the use of probiotics, prebiotics, and diets in this disorder.”

  • The paper relies on this without support.

    There is documented low-grade inflammation in IBS.

    “However, the documented low-grade inflammation in IBS, the suggestive preliminary data from animal studies (52), and the noticeable paucity of clinical data in this area emphasize the need for further investigation to enable more solid conclusions regarding this treatment option in IBS.”
6 of 6

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Emerging data support the existence of dysbiosis in a subset of IBS: a decreased complexity in composition, temporary instability, and changes in the mucosa-associated microbiota, with an increase in Bacteroides and Clostridia and a reduction in Bifidobacterium.

    “Nonetheless, emerging data support the existence of dysbiosis in a subset of IBS [59] : a decreased complexity in composition [60] , temporary instability [61] , and changes in the mucosa-associated microbiota, with an increase in Bacteroides and Clostridia and a reduction in Bifidobacterium [62] .”

    From Intestinal microbiota in health and disease: Role of bifidobacteria in gut homeostasis (2014) · cites this paper as [59]

  • Modulation of enteric sensorimotor function, through alterations in bile acid metabolism by microbiota, has been described in several in vitro studies.

    “Modulation of enteric sensorimotor function, through alterations in bile acid metabolism by microbiota, has been described in several in vitro studies [59] .”

    From Intestinal microbiota in health and disease: Role of bifidobacteria in gut homeostasis (2014) · cites this paper as [59]

Cites

Flagged first, then by citations

1 of the 205 references couldn’t be matched to a known paper.

Research works printed but not linked: 6

  1. Cuoco L, 2006, Minerva Gastroenterol Dietol, 52, 89
  2. Majewski M, 2007, Adv Med Sci, 52, 139
  3. Nayak AK, 1997, Indian J Gastroenterol, 16, 137
  4. Pimentel M, 2003, Am J Gastroenterol, 98, 412
  5. Roberts L, 2006, Br J Gen Pract, 56, 115
  6. Tana C, 2010, Neurogastroenterol Motil, 22, 512

Cited by

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Related

Authors
Ringel, Y., & Maharshak, N.
Affiliations
University of North Carolina at Chapel Hill (US)
Corresponding author
Ringel, Yehuda
ORCID
Maharshak, Nitsan
Venue
American Journal of Physiology-Gastrointestinal and Liver Physiology
Publisher
American Physiological Society
Published
2013-10-15
Volume
305
Issue
8
Pages
G529-G541
ISSN
  • 0193-1857 (ISSN-L)
  • 1522-1547
DOI
10.1152/ajpgi.00207.2012
PMC
PMC3798736
OpenAlex
W2142798775
Semantic Scholar
6d3e52f8b16f5bfae1172c1f647999a36a049982
Cited by
115
References
205
Citations by year
2026: 4 · 2025: 6 · 2024: 5 · 2023: 7 · 2022: 5 · 2021: 6 · 2020: 6 · 2019: 5 · 2018: 10 · 2017: 11 · 2016: 14 · 2015: 20 · 2014: 14 · 2013: 2
FWCI
2.65
Type
journal article
Language
en
Open access
Locations
  • American Journal of Physiology-Gastrointestinal and Liver Physiology (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
National Institute of Diabetes and Digestive and Kidney Diseases (R03DK084294, DK075621, K23DK075621, DK084294)
Topics
  • Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
  • Health Sciences › Medicine › Epidemiology › Microscopic Colitis
Keywords
irritable bowel syndrome, gut microbiota, immune function, gut-brain axis, IBS pathogenesis, dysbiosis, gastrointestinal symptoms
MeSH terms
Humans, Intestines, Irritable Bowel Syndrome

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-06.

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