Irritable Bowel Syndrome Group Research Articles

Activation of corticotropin-releasing hormone system in the locus ceruleus induces the visceral sensitivity of irritable bowel syndrome rats

Objective To study the role of corticotropin-releasing hormone (CRH) system in locus ceruleus (LC) in irritable bowel syndrome (IBS) and to explore its molecular mechanism. Methods The IBS rat was established by maternal separation following with postnatal stress. The tissues sample of LC was obtained by micropunched nuclei. The expression of c-Fos, CRH and its receptors including corticotropin-releasing hormone receptor (CRHR) 1 and CRHR2 of rats’ LC tissues of control group and IBS group was detected by quantitative polymerase chain reaction(PCR). The expression of DNA methyltransferase (DNTM) 1, DNMT3a and DNMT3b at the mRNA level were also measured. In addition, the expression of histone methyltransferase ASH2-like protein (ASH2L) and SET and MYND domain containing 2 (SMYD2) was determined by Western blotting. T test was used for statistical analysis. Results The rectal pneumatic pressure of IBS group was lower than that of control group ((69.82±5.47) mmHg vs. (86.86±5.98) mmHg; 1 mmHg=0.133 kPa), however compared with that of control group, the expression of c-Fos at the mRNA level increased (2.11±0.44 vs.1.00±0.19), and the differences were statistically significant (t=6.215 and 2.321, P 0.05). Conclusions Maternal separation combined with postnatal stress affect the transcription of Crh gene in LC and cause the activation of the stress regulation network CRH and norepinephrine system, resulting in the increase of the visceral sensitivity of rats. The abnormal transcription of Crh gene may be related with SMYD2-mediated histone H3K36 methylation, but not related with the modification of DNA methylation. Key words: Irritable bowel syndrome; Locus ceruleus; Maternal separation stress; Corticotropin-releasing hormone system; Epigenetics

A Simultaneous Multidisciplinary Evaluation of Irritable Bowel Syndrome in Egyptian Patients: Dietary, Psychiatric, Microbiologic and Autonomic Aspects

Background and Aim: Irritable bowel syndrome (IBS) is a common medical disorder that may be severe enough to impair the quality of life. This study aimed to assess the role of each of dietary, psychiatric, autonomic, and microbiology background and their interactions in Egyptian patients with IBS. Patients and Methods: Forty adult patients diagnosed with IBS, equally divided into 2 groups the diarrhea predominant and the constipation predominant, were recruited from the Endoscopy Unit. Dietary assessment was done by monthly food frequency questionnaire. Psychiatric assessment was done by both the Eysenck Personality Questionnaire (EPQ) and Hopkins Symptom Checklist (HSCL-90). Microbiologic evaluation was done by faecal cultures and neurophysiologic autonomic evaluation was done via the sympathetic skin response and the parasympathetic R-R interval variation. Another 20 healthy subjects were included as control group. Results: All IBS patients were young, with significant female predominance (P = 0.007), particularly in IBS-C group (20/20; 100%, P = 0.003). Psychologically, abnormal scores of neuroticism, extraversion and criminality, and depression, obsessive compulsion, somatization, sensitivity and anxiety in both IBS groups with particularly extraversion, criminality and depression were significantly higher in constipation subtype. Microbiologically, Bacteroids were significantly related to IBS, while Klebsiella was significantly deficient without significant difference between its groups. On the contrary, neither diet nor autonomic activity showed any significant relation. Conclusions: IBS is a disorder induced by many factors and affected by several interacting agents, thus revealing controversial results when studied simultaneously.

Tryptophan Metabolites in Irritable Bowel Syndrome: An Overnight Time-course Study.

Background/AimsPatients with irritable bowel syndrome (IBS) often report poor sleep quality. Whether poor sleep is associated with tryptophan (Trp) metabolites is unknown. We compared serum Trp metabolites in women with IBS and healthy controls (HCs) using targeted liquid chromatography mass spectrometry (LC-MS)-based profiling. In IBS only, we explored whether Trp metabolites are associated with IBS symptoms and subjective and objective sleep indices, serum cortisol, plasma adrenocorticotropic hormone (ACTH), and cortisol/ACTH levels.MethodsBlood samples were obtained every 80 minutes in 21 HCs and 38 IBS subjects following an anticipation-of-public-speaking stressor during a sleep laboratory protocol. Subjects completed symptom diaries for 28 days. Adjacent values of metabolites were averaged to represent 4 time-periods: awake, early sleep, mid-sleep, and mid-to-late sleep. Thirteen of 20 targeted Trp metabolites were identified.ResultsTen of 13 Trp metabolites decreased across the night, while nicotinamide increased in both groups. A MANOVA omnibus test performed after principal component analysis showed a significant difference in these 13 principal component (P = 0.014) between groups. Compared to HCs, nicotinamide levels were higher and indole-3-lactic acid levels lower in the IBS group. Melatonin and indole-3-acetic acid levels were associated with several subjective/objective sleep measures; decreased stool consistency/frequency and abdominal pain were positively associated with melatonin and serotonin in the IBS group. The kynurenine and kynurenic acid were associated with ACTH (positively) and cortisol/ACTH (negatively).ConclusionsNighttime Trp metabolites may provide clues to poor sleep and stress with IBS. Further study of the mechanism of metabolite action is warranted.

Identification of Gut Microbiota and Metabolites Signature in Patients With Irritable Bowel Syndrome

Background and Aims: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. However, the underlying mechanism of IBS is not fully understood. The aim of this study was to investigate potential mechanism and novel biomarkers of IBS through evaluation of the metabolomic and microbiologic profile.Methods: Fecal samples were collected from 15 irritable bowel syndrome patients and 15 healthy controls. By using gas chromatography coupled to time-of-flight mass spectrometry (GC-TOFMS) and 16S rDNA amplicon sequencing, fecal metabolites and microbiota of healthy controls and the IBS patients were measured.Results: IBS patients had a significantly differential metabolite profile as compared to healthy controls, and 4 clusters with 31 metabolites, including a group of amino acids and fatty acids, were significantly up-regulated as compared to the healthy controls. In addition, 19 microbes were significantly up-regulated, and 12 microbes were down-regulated in the IBS group, when compared with the healthy controls. Some clusters of fecal metabolites or microorganisms were significantly correlated with the severity of IBS symptoms, such as the frequency of abdominal pain/discomfort and the number of bowel movements. Correlation of the metabolite levels with abundances of microbial genera showed some statistically significant metabolite-microbe associations. Four differentially abundant amino acids clustered together were positively correlated with some microbes, including Lachnospira, Clostridium, and so on.Conclusion: The finding of this study puts a global perspective on metabolomics and microbiota profiling in IBS patients and provides a theoretical basis for future research on pathophysiology of IBS.

Peroxiredoxin 1 as an inflammatory marker in diarrhea-predominant and postinfectious irritable bowel syndrome.

Low-grade inflammation occurs in some patients with irritable bowel syndrome (IBS). However, the exact inflammatory markers of IBS and the relationship of these markers with IBS subtypes and symptoms are poorly defined. Peroxiredoxin 1 (PRDX1) plays an important role in inflammatory responses, including intestinal inflammation. We investigated whether PRDX1 is associated with the diagnosis, subtypes, and symptom severity of IBS. A total of 177 IBS patients and 174 sex- and age-matched healthy controls (HCs) were recruited. The PRDX1 levels in the sera and colonic mucosa of the participants were detected by enzyme-linked immunosorbent assays and immunohistochemistry. The severity of IBS symptoms was assessed using the IBS Severity Scoring System (SSS) questionnaire. The PRDX1 levels in the sera (F=71.81, P<.001) and colonic mucosa (F=5.359, P<.001) of postinfectious (PI-IBS) and diarrhea-predominant IBS (IBS-D) groups were significantly higher than those of the other three IBS subtypes and HC group. The PRDX1 level in the serum and colonic mucosa of IBS-D (serum, P<.01, mucosa, P<.001) and PI-IBS (serum, P<.05, mucosa, P<.001) groups with the most severe symptoms was significantly higher than that in the groups with mild and moderate symptoms. Correlation analysis revealed that in patients with IBS-D (P<.001) and PI-IBS (P<.05), the levels of PRDX1 and TNF-α in sera had a significant positive correlation with IBS-SSS. Elevated PRDX1 in the serum and colon mucosa may be closely related to the progression of IBS (especially IBS-D and PI-IBS) and the expression of gastrointestinal symptoms.

Effectiveness and applicability of low FODMAP diet in the irritable bowel syndrome: Preliminary results of a prospective study

Abstract: Introduction: Irritable bowel syndrome (IBS) is a very common entity that alters patient’s life quality worldwide. Several therapeutic modalities are available with variable results. Recently, the low-FODMAP diet effect on IBS symptoms has been proven. The aim of our study was to study the efficiency of this diet and to assess its applicability in a Tunisian IBS group of patients. Methods: A longitudinal, prospective study including 34 patients with IBS was conducted. Patients responded to a food frequency survey and had to follow a low FODMAP diet with a dietary guide education for 3 weeks. After the diet, a telephone questionnaire was conducted to evaluate adherence and treatment efficiency. Results: Mean of the population age was 56.5 (21 – 83 years) with a sex ratio of almost 1⁄4. The initial food survey showed a large consumption of white bread and fruits. Tolerance to rich in FODMAP foods was variable among patients. Up to 97% of patients adhered to the low FODMAP diet. A decrease in abdominal pain in 88% of cases and in bloating in 64.7% of cases (p = 0.007) were noted after the diet. Conclusion: In our patients, the low FODMAP diet showed satisfactory results with good adherence, and improvement of IBS symptoms. However, it is important to note the difficulty of a long-term diet in a population with a variable alimentary habit. Key words: low FODMAP diet; irritable bowel syndrome, applicability, Tunisia

478 Assessing the Relation Between Irritable Bowel Syndrome and Nonalcoholic Liver Disease

INTRODUCTION: Irritable bowel syndrome (IBS) and nonalcoholic fatty liver disease (NAFLD) are both very common gastroenterological disorders. There are recent reports in the literature linking these disorders together, but to date there are no large studies to highlight this relation. We aimed in this study to investigate whether IBS is an independent risk factor for NAFLD. METHODS: Using data from the National Inpatient Sample (NIS) database between 2003 and 2014, we identified patients who were diagnosed with IBS using appropriate ICD 9 coding. The control group was the patients who did not have a diagnosis of IBS. We then performed multivariate logistic regression analysis for the association between IBS and NAFLD. RESULTS: The total population was comprised of 84,456,866 patients, of which 637,942 (0.75%) were diagnosed with IBS. IBS patients were older (58 vs 57), more likely to female (82.7% vs 60.1%) and less likely to be African American (8.9% vs 14.8%) (P &lt; 0.001 for all). In addition, IBS patients had less diabetes mellitus (DM) with or without complications (2.6% vs 3.8) and (13.7% vs 17%) respectively (P &lt; 0.001). On the other hand, individuals in the IBS group had more obesity (11% vs 8.2%), hypertension (HTN) (47.6% vs 43.6%), hyperlipidemia (HLD) (20.6% vs 16%) (HLD) and hypothyroidism (16.5% vs 9.2%) (P &lt; 0.001 for all). Using Multivariate logistic regression, and after adjusting for potential cofounding factors including (age, race, gender,obesity, HTN, HLD, DM and hypothyroidism), individuals in the IBS group had a statistically significant higher rate of NAFLD (Odds Ratio [OR], 3.204, 95% confidence interval [CI], 3.130 -3.279, P &lt; 0.001) compared with the non-IBS group. CONCLUSION: In our study patients with IBS were three times more likely to have NAFLD. This finding supports the recent reports that suggest that the changes in gut microbiota, impaired intestinal permeability and impaired intestinal motility in IBS may also play an important role in NAFLD development.

Distinct Microbial Populations Exist in the Mucosa-associated Microbiota of Diarrhea Predominant Irritable Bowel Syndrome and Ulcerative Colitis.

The goal of this study was to observe the bacterial colonization in the intestinal mucosa in the patients with diarrhea predominant irritable bowel syndrome (IBS-D) and ulcerative colitis (UC), and compare the mucosa-associated microbiota among the IBS-D patients, UC patients and the healthy control, and explore the correlation of the mucosa-associated microbiota with clinical manifestations. A total of 20 IBS-D patients, 28 patients with UC (16 active, 12 inactive) and 16 healthy subjects were enrolled in the study. They all underwent colonoscopies in the Gastrointestinal Endoscopy Center in the Second Affiliated Hospital of Xi'an Jiaotong University from June 2016 to October 2016. The mucosa specimens were taken at the junction of rectum and sigmoid colon for fluorescent in situ hybridization (FISH). Then the observed mucosa-associated microbiota was counted and compared. (1) In the IBS-D patients, the mucosa-associated bacteria were found to colonize in the surface of mucosa and the adjacent mucin layer. And in active UC, Escherichia coli, and Bacteroides were found in the lamina propria, in addition to bacterial colonization in the above-mentioned areas. (2) The total count of mucosa-associated bacteria and the individual counts of E. coli, Clostridium, and Bacteroides were significantly increased, and Bifidobacteria significantly decreased (P<0.05) in the IBS-D patients and UC patients. Counts of Lactobacillus were decreased only in UC patients compared with the healthy control. And a significantly larger variation of the above-mentioned bacterial counts was found in the patients with UC, particularly in those with active UC, compared with those with IBS-D (P<0.05); the counts in the UC group were 1.3 to 5.3 times more or less than those in the IBS-D group. (3) Compared with healthy controls and IBS-D, the total count of bacteria and the individual counts of E. coli and Bacteroides in the lamina propria in active UC were significantly increased (P<0.05). (4) A significant negative correlation of the counts of Lactobacillus and Bifidobacteria with the defecation frequency and fecal characteristics (P<0.05) was found in the IBS-D patients; in those with UC, both the total count of bacteria and the individual counts of E. coli, Clostridium, Bacteroides, Lactobacillus, and Bifidobacteria were significantly correlated, positively or negatively, with the related clinical manifestations and the activity of the disease (P<0.05). Compared with the healthy control, intestinal microecology was changed most obviously in UC with much smaller differences though in the same direction in IBS-D. The translocation of some bacteria into the lamina propria was found in UC, particularly in active UC. The changes of mucosa-associated microbiota were related more or less to some clinical manifestations in IBS-D and UC.

479 Length of Time Spent in the Outpatient Setting With Patients With Irritable Bowel Syndrome: Analysis of the National Ambulatory Medical Care Survey

INTRODUCTION: Irritable bowel syndrome (IBS) is a chronic and debilitating functional gastrointestinal disorder that affects 9%-23% of the population across the world. Based on IBS association with psychological symptoms such as anxiety and depression, it is assumed that patients with this condition require more time during outpatient visits than the average patient. The purpose of this study was to evaluate differences in time spent by physicians in the outpatient setting with patients with IBS versus patients with other conditions. METHODS: The National Ambulatory Medical Care Survey was searched using International Classification of Diseases - Ninth Revision (ICD-9) diagnosis codes for patients seen in the outpatient setting for IBS for the years 2011-2015. Time spent during the outpatient visits was also gathered. Patients were separated into two groups, those with IBS and those with other conditions. Data was analyzed with regards to patient age, sex, and duration of outpatient visit. Statistical comparisons were made using Statistical Package for the Social Sciences (SPSS) with chi-square and student T tests with a significance level of 0.05. RESULTS: 175,863 outpatient visits were identified, with 381 patients with IBS and 175,483 patients with other conditions. Patients with IBS were significantly older (mean age of 49.3 vs 46.1, P = 0.0129) and had a longer duration of visit with the physician (24.7 minutes vs 22.5 minutes, P = 0.0007). The IBS group had a significantly larger proportion of females compared to the other conditions group (80.05% vs 57.16%, P &lt; 0.0001) CONCLUSION: In this study, it was found that IBS patients take a significantly longer clinic time compared to patients with other conditions. These patients were more likely to be older and female. Various comorbid factors such as fatigue, lack of sleep, anxiety, and depression are potential contributors to the extended amount of time needed for these patients. Physicians should expect to potentially spend more time with these patients during their clinic visits and adjust their schedules accordingly to provide the best quality of care for patients with IBS.

Abdominal Wall Pain or Irritable Bowel Syndrome: Validation of a Pediatric Questionnaire.

A questionnaire study demonstrated that some adult patients who were diagnosed with irritable bowel syndrome (IBS) were in fact having an abdominal wall pain syndrome, such as anterior cutaneous nerve entrapment syndrome (ACNES). The aim of the present study was to investigate whether a pediatric version of this questionnaire was useful in diagnosing abdominal wall pain syndromes in children with chronic abdominal pain (CAP). An 18-item questionnaire was tested in 3 groups of children with CAP: group 1, children who underwent surgery for ACNES (n = 42); group 2, children who were found to have ACNES after an outpatient analysis (n = 57); and group 3, children diagnosed with IBS (n = 53). Qualities including internal consistency (Cronbach α), cut-off points and a ROC-curve were calculated using standard statistical analysis. Questionnaire response rates in the three populations of CAP children ranged from 69% to 92%. When comparing ACNES and IBS groups, 17 of 18 questions were discriminative (P < 0.01, Cronbach α 0.74). Total questionnaire scores ranged from 0 (IBS likely) to 17 points (ACNES likely). A median 13-point score (range 8-17) was found in both ACNES groups. In contrast, a median 8-point score was calculated in children with IBS (range 3-13, P < 0.01). Using an 11-point cut-off score, a child with CAP was diagnosed with ACNES with 86% sensitivity and 89% specificity. A ROC curve with an AUC of 0.94 was obtained. A 17-item questionnaire showed good diagnostic test properties and may aid in distinguishing ACNES from IBS in pediatric populations with chronic abdominal pain.

Use of antidepressants and risks of restless legs syndrome in patients with irritable bowel syndrome: A population-based cohort study.

Previous research has suggested an association between antidepressants use and clinical restless legs syndrome (RLS) in patients, but there has never been a single study investigating the risk of RLS in irritable bowel syndrome (IBS) patients treated with antidepressants. Hence, we aimed to explore the association between IBS and RLS and to examine the risk of RLS in IBS patients treated with antidepressants. With the use of the National Health Insurance Research Database of Taiwan, 27,437 adults aged ≥ 20 years with newly diagnosed IBS (ICD-9-CM Code 564.1) and gender- and age-matched 54,874 controls without IBS were enrolled between 2000 and 2012. All patients were followed-up until RLS diagnosis, withdrawal from the National Health Insurance program, or end of 2013. We used the Cox proportional hazards model to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) of RLS. RLS was more prevalent in IBS patients than in the non-IBS group (7.57 versus 3.36 per 10,000 person-years), with an increased risk of RLS (adjusted HR [aHR], 1.91; 95% CI, 1.52–2.40). Multivariate Cox proportional hazards analysis identified older age (age, 51–65 years; aHR, 1.67; 95% CI, 1.09–2.56; and age > 65; aHR, 1.59; 95% CI, 1.02–2.48), hypothyroidism (aHR, 4.24; 95% CI, 1.92–9.37), CAD (aHR, 1.70; 95% CI, 1.17–2.48), and depression (aHR, 3.15; 95% CI, 2.14–4.64) as independent RLS risk factors in IBS patients. In addition, the male SSRIs users were associated with significantly higher risk of RLS (aHR, 3.05 95% CI, 1.34–6.92). Our study showed that the IBS group has higher risk of RLS. Moreover, SSRIs use may increase the risk of RLS in male IBS patients.

Mechanical analysis of intestinal contractility in a neonatal maternal deprivation irritable bowel syndrome rat model

The aims of the present study are to investigate biomechanical properties and provide mechanical analysis of contractility in ileum and colon in a neonatal maternal deprivation (NMD) irritable bowel syndrome (IBS) rat model. Mechanical testing was done on segments from ileum and colon in 25 IBS rats and 13 Control rats. Morphometric data were obtained from digitized images of the segments at no-load and zero-stress states. Pressure and diameter changes were measured during flow and ramp distensions under active and passive experimental conditions. Circumferential stresses (force per area) and strains (deformation) were computed with referenced to the zero-stress state. The contraction frequency was analyzed. Contraction thresholds and maximum contraction amplitude were calculated in terms of mechanical stress and strain. Compared with controls, the IBS rats had lower body weight (P < 0.01), smaller colonic opening angle (P < 0.05), higher colonic contraction frequency (P < 0.05 and P < 0.01) and lower contraction thresholds of pressure, stress and strain in both ileum and colon (P < 0.05 and P < 0.01). The maximum contraction pressure, stress and strain did not differ between IBS and Control groups (P > 0.05). In conclusion, the pressure, stress, and strain to evoke contractility in ileum and colon were lower whereas the frequency of induced colon contractions was higher in NMD IBS rats compared to normal rats. Furthermore, zero-stress state remodeling occur in colon in NMD IBS rats. Further studies on the association between intestinal biomechanical properties, hypersensitivity and afferent signaling in the IBS animal models are warranted.

Defense Mechanisms in Patients with Irritable Bowel Syndrome and Their Relationship with Symptom Severity and Quality of Life.

BACKGROUND Despite the fact that there is theoretical evidence about the association between unconscious defense mechanisms and irritable bowel syndrome (IBS), experimental evidence in this regard is limited. The aim of the present study was to compare the defense mechanisms used by the patients with IBS and a control group, and to investigate the relationship between these mechanisms with the severity of the disease and patients’ quality of life. METHODS Fourty-five patients with IBS (mean age of 37.1 years; 14 males) and 45 controls (mean age of 38.0 years; 13 males) were evaluated. IBS diagnosis was determined based on Rome III criteria and the predominant pattern of the disease was determined based on the patient’s history (13 diarrheapredominant, 16 constipation-predominant, and 16 alternating IBS). Defense Style Questionnaire-40, IBS Severity Scale, and IBS-Quality of Life questionnaire were used.RESULTSThe mean scores of projection, acting-out, somatization, autistic fantasy, passive-aggression, and reaction formation in the IBS group were significantly higher than the control group and the mean scores of humor and anticipation mechanisms were higher in the control group. There was no significant correlation between the score of defense mechanisms and the severity of IBS and the patients’ quality of life.CONCLUSIONThe severity of immature defenses in the IBS group was significantly higher, whereas the severity of mature defenses was higher in the control group. These defenses were not correlated with the severity of IBS. Considering the limited sample size, these relationships need to be more investigated.

Multi-omics Analysis of Gut Microbiota and Metabolites in Rats With Irritable Bowel Syndrome.

Irritable bowel syndrome (IBS) is a common gastrointestinal dysfunctional disease. The pathophysiology of IBS is, however, largely unknown. This study aimed to determine whether evaluation of fecal metabolite and microbiota profiles may offer an opportunity to identify a novel pathophysiological target for IBS, and to reveal possible gut microbe–metabolite associations. By using gas chromatography coupled to time-of-flight mass spectrometry (GC-TOFMS) and 16S rRNA gene sequencing, we measured fecal metabolites and microbiota of the control and water avoidance stress (WAS)-induced IBS rats. We found a significantly differential metabolite profile between the IBS and control groups; a cluster of metabolites was also found to be significantly associated with the amount of defecations. Moreover, the WAS group exhibited a decreased alpha diversity of the microbial population as compared to the control group. However, the characteristics of gut microbiota could not differentiate the IBS group from the control group. Correlation of the metabolite level with the number of microbial genera showed no significant association between the control and IBS groups. This study provides a global perspective on metabolomics and microbiota profiling in WAS-induced IBS model and a theoretical basis for research on the pathophysiology of IBS.

Changes of the postcentral cortex in irritable bowel syndrome patients.

The postcentral cortex (poCC) is commonly found to respond to visceral stimulation, but researchers usually pay less attention to this role of the poCC in the patients with functional gastrointestinal disorders, because it is a primary receptor for general bodily feeling of touch, such as temperature and pain. The current study focuses on the changes around the poCC in irritable bowel syndrome (IBS) patients based on the resting-state functional magnetic resonance imaging, aiming to investigate whether the poCC-centric brain metrics may be directly related to visceral perception. In the study, we calculated the regional homogeneity, seed-based correlation (SBC) and nodal centralities of the poCC to explore the changes in the regional activity and information flow around the poCC in IBS patients. Moreover, we examined the performance of the poCC-centric features in classifying the IBS group and healthy group in comparison to those features unrelated to the poCC. The results found that central alterations around the poCC in IBS patients were associated with the level of visceral pain, and exhibited a better discriminative power than those around the whole brain and the insula when classifying the IBS group and healthy group. In conclusion, the preliminary investigation provided fundamental advances in understanding the roles of the poCC in the pathphysiology of the IBS.

Constipation is associated with tension type headache in women.

Women diagnosed with TTH were questioned about headache pattern and severity, and accompanying factors, as well as being screened for IBS according to the Rome III criteria. The participants were divided into two groups: constipation-dominant IBS (IBS-C) group and "others", with a total of 115 individuals included in the study. Of the 115 patients; 48 (41.8%) of the women had IBS-C criteria while 67 (58.2%) described mixed-type IBS or diarrhea-dominant IBS. There were no significant differences in terms of mean age (p = 0.290), body mass index (p = 0.212), visual analog scale (p = 0.965), duration of attacks (p = 0.692), and episodic/chronic type (p = 0.553). Osmophobia was seen in 43.5%; phonophobia in 68.7%, and photophobia in 47.0% of the patients, and only osmophobia was significantly associated in women in the IBS-C group (p = 0.001). In female patients with TTH, a higher level of constipation was detected. The relationship of these two diseases suggests that they may share common mechanisms. This is the first study showing the relationship of osmophobia with constipation.

Vascular endothelial growth factor, endostatin levels and clinical features among patients with ulcerative colitis and irritable bowel syndrome and among healthy controls: a cross-sectional analytical study.

Increased angiogenetic activity in inflammatory bowel disease (IBD) has been shown in previous studies. The aim of this study was to evaluate the relationship of serum vascular endothelial growth factor (VEGF) and endostatin levels with clinical features and mucosal expression in patients with ulcerative colitis (UC). Cross-sectional analytical study conducted in a tertiary-level public hospital. Serum VEGF and endostatin levels were determined in 82 individuals: 39 with UC, 28 with irritable bowel syndrome (IBS) and 15 healthy controls (HCs), using enzyme-linked immunosorbent assays (ELISA). VEGF and endostatin expressions were studied using immunohistochemistry (IHC). Mean serum VEGF and endostatin levels were significantly higher in patients with UC than in patients with IBS and in HCs (511.9 ± 377.5 pg/ml, 305.0 ± 121.42 pg/ml and 36.1 ± 40.6 pg/ml; P = 0.001 for VEGF; and 155.50 ± 59.8 ng/ml, 116.9 ± 23.8 ng/ml and 102.2 ± 22.4 ng/ml; P < 0.001 for endostatin, respectively). There was a positive correlation between serum VEGF and endostatin levels (r = 0.422; P < 0.01). Mean H-scores for VEGF expression were higher in the active UC group than in the inactive UC and IBS groups, in the stroma, endothelium and epithelium. Mean H-scores for endostatin expression were higher in the active UC group than in the inactive UC and IBS groups, in the stroma and endothelium. There was no endostatin expression in the epithelium. Increased endostatin appears to be a defensive reaction to increased VEGF in patients with UC.

Metabolomics analysis revealed metabolic changes in patients with diarrhea-predominant irritable bowel syndrome and metabolic responses to a synbiotic yogurt intervention.

Irritable bowel syndrome is a gastrointestinal disorder which can influence human metabolism. It has been demonstrated that probiotics are beneficial in controlling IBS. Thus, the main objective of the present study was to determine metabolic changes in response to diarrhea predominant irritable bowel syndrome (IBS-D) and to investigate the metabolic effects of a synbiotic intervention on serum, urine, and stool samples from IBS-D patients and healthy controls using proton nuclear magnetic resonance (1HNMR). A 1HNMR-based metabolomics study was conducted on urine and serum metabolites from 16 healthy and eight IBS-D participants at baseline and after 4weeks of a synbiotic yogurt intervention. At the baseline, serum acetoacetate, myo-inositol, and sarcosine concentrations were higher and threonine and methionine concentrations were lower in the IBS-D cohort than the control group. Moreover, Indoxyl-sulfate concentration of urine was lower and dimethylamine and taurine were higher in the IBS-D group. After intervention, serum concentration of ketone bodies decreased, choline, phenylalanine, and branched-chain amino acids increased in IBS-D group. Metabolomics analysis indicated a shift in one-carbon metabolism. Thus, the level of serum homocysteine was determined and found to be higher in the IBS-D cohort at baseline, and then decreased after the intervention. IBS causes a shift in one-carbon metabolism and these changes can be reversed by a synbiotic intervention. An increase in the number of fecal Lactobacilli and an improvement in the health status of IBS-D patients were also observed in response to intervention.

Microstructural changes in the brain in elderly patients with irritable bowel syndrome.

ObjectiveIt is unclear how alterations in gray matter volume and white matter density affect elderly patients with irritable bowel syndrome (IBS). This study aimed to investigate the relationship between structural changes in the brain and psychological stress in elderly IBS patients.MethodsEighteen IBS patients and 12 healthy controls underwent structural magnetic resonance imaging. Voxel‐based morphometry and diffusion tensor imaging analysis were used to identify abnormalities in cortical regions and white matter, respectively.ResultsThe IBS group showed a significant GMV reduction in the cingulate gyrus, occipital lobe, hippocampus, frontal lobe, medial frontal gyrus, superior frontal gyrus, and limbic lobe as well as a higher GMV in the insula, superior temporal gyrus, angular gyrus, and supramarginal gyrus. Diffusion tensor imaging indicated that the IBS group had lower fractional anisotropy in the corpus callosum, upper corona, fornix, internal capsule, and brainstem. Additionally, IBS patients showed higher mean diffusivity in the cingulate gyrus, corpus callosum, upper corona, internal capsule, external capsule, fornix, and superior longitudinal fasciculus.ConclusionStructural changes in the brain play a role in the condition of elderly IBS patients. Psychological stress is an important factor for developing IBS via the hypothalamic‐pituitary‐adrenal axis.

Transcriptome and methylome profiling in a rat model of irritable bowel syndrome induced by stress.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that is associated with psychological stress. However, the full landscape of IBS-related epigenetic factors remains unveiled and needs to be elucidated. The water-avoidance stress (WAS) method was used to induce a rat IBS model. Each rat was monitored, and its defecation and behavior were recorded. Total colon RNA was isolated and subjected to Affymetrix GeneChip analysis. Reduced Representation Bisulfate Sequencing (RRBS) was applied to determine the genome-wide methylation pattern in both IBS and control rats. Rats with IBS egested a significantly increased amount of dry and loose stools compared with the control animals, without significant changes in body weight. Compared with the control group, 309 genes were upregulated and 224 genes were downregulated in the colon of the IBS rats. Notch signaling and focal adhesion were increased in the differentially expressed genes (DEGs). A total of 541 genes had significant lower methylation level and 626 genes had significantly higher methylation level in their promoter regions. Adherens junction and leukocyte transendothelial migration were enriched in the differentially methylated genes (DMGs). Few genes were identified in common in both DEGs and DMGs, suggesting that gene expression was not altered by promoter methylation. Reverse transcription-quantitative polymerase chain reaction validation revealed that the mRNA levels of SSX2IP, PARD3 and VCL were significantly downregulated in the IBS group, in accordance with hypermethylation of their promoters. In summary, the present study used a WAS-induced IBS rat model to provide transcriptome and methylome profiling. Most DEGs were associated with Notch signaling and focal adhesion, and only a few were altered by promoter methylation. The present results demonstrated that psychological stress could influence the integrity of the intestinal mucosa barrier and regulate inflammatory response.