Associations of clinical features of functional bowel disorders with gut microbiota characteristics in adolescents: A pilot study

Background. Obesity is a multifactorial disease that is one of the important public health problems in the 21st century. Functional bowel disorders in obese children and adolescents are one of the most common pathologies of the digestive tract. The aim: to characterize the bacteriological composition of the colon microbiota in obese adolescents and identify its associations with the clinical manifestations of functional bowel disorders.Materials and methods. The study included 20 adolescents aged 11–17 years. Stool consistency was assessed using the Bristol Stool Scale. The study of biological material was carried out using standard bacteriological methods. To assess the strength of the relationship between the nominal variables, Cramer’s V test was used.Results. It has been shown that in adolescents with obesity and functional bowel disorders, there is a decrease in the number of representatives of bifidoflora, an increase in the microbial density of Escherichia coli with altered enzymatic properties and an excessive growth of potentially pathogenic enterobacteria. In obese adolescents with functional bowel disorders, abdominal pain associated with the act of defecation is associated with the presence of enterobacteria and E. coli with altered enzymatic properties. Rare bowel movements are associated with an increased abundance of Enterococcus spp. and the presence of opportunistic Enterobacteriaceae microorganisms. Frequent bowel movements are associated with the presence of E. coli with altered enzymatic properties and Clostridium spp. In the presence of loose stool, Clostridium spp. is present; unstable stool (alternation of hard and liquid stools in one patient) is associated with a decrease in the number of lactobacilli and E. coli with normal enzymatic properties, the appearance of E. coli with altered enzymatic properties, opportunistic microorganisms of Enterobacteriaceae family and Clostridium spp. Conclusion. The relationship between the clinical symptoms of functional bowel disorders and changes in the composition of the gut microbiota in obese adolescents may be a justification for conducting in-depth studies aimed at finding early predictors of functional bowel diseases associated with obesity in the adult cohort.

Targeting Mechano-Transcription Process as Therapeutic Intervention in Gastrointestinal Disorders

Mechano-transcription is a process whereby mechanical stress alters gene expression. The gastrointestinal (GI) tract is composed of a series of hollow organs, often encountered by transient or persistent mechanical stress. Recent studies have revealed that persistent mechanical stress is present in obstructive, functional, and inflammatory disorders and alters gene transcription in these conditions. Mechano-transcription of inflammatory molecules, pain mediators, pro-fibrotic and growth factors has been shown to play a key role in the development of motility dysfunction, visceral hypersensitivity, inflammation, and fibrosis in the gut. In particular, mechanical stress-induced cyclooxygenase-2 (COX-2) and certain pro-inflammatory mediators in gut smooth muscle cells are responsible for motility dysfunction and inflammatory process. Mechano-transcription of pain mediators such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) may lead to visceral hypersensitivity. Emerging evidence suggests that mechanical stress in the gut also leads to up-regulation of certain proliferative and pro-fibrotic mediators such as connective tissue growth factor (CTGF) and osteopontin (OPN), which may contribute to fibrostenotic Crohn’s disease. In this review, we will discuss the pathophysiological significance of mechanical stress-induced expression of pro-inflammatory molecules, pain mediators, pro-fibrotic and growth factors in obstructive, inflammatory, and functional bowel disorders. We will also evaluate potential therapeutic targets of mechano-transcription process for the management of these disorders.

Validity and Reliability of the Japanese Version of the Cognitive Scale for Functional Bowel Disorders

BackgroundThe Cognitive Scale for Functional Bowel Disorders (CS-FBD) is a useful measure to assess maladaptive cognition, and focuses on how functional bowel disorders relate to negative thoughts, perfectionism, and social desirability. This study aimed to confirm the reliability and validity of the Japanese version of the CS-FBD (CS-FBD-J). MethodsParticipants comprised 192 students (20.2±3.0 years) and 22 outpatients diagnosed with irritable bowel syndrome (IBS) (38.0±13.0 years). There were 76 students who met the diagnostic criteria for IBS, and two students who received treatment for IBS. Participants completed questionnaires containing the CS-FBD-J, IBS Severity Index (IBS-SI), Visceral Sensitivity Index (VSI), 24-item Dysfunctional Attitudes Scale (DAS-24), and Hospital Anxiety and Depression Scale (HADS).ResultsOur factor analysis revealed that the CS-FBD-J had a unidimensional factor structure, and that the factor loadings for 2 out of the 25 items were less than 0.4. After excluding the two items from the analysis, a single factor of the 23-item version accounted for 45.85% of the total variance. The CS-FBD-J scores had significant moderate correlations with the IBS-SI (r = 0.492~0.574) and VSI (r = 0.531~ 0.557) scores in the IBS group and the control group. Correlation between the DAS-24 and the CS-FBD-J was not significant (r = 0.179 ~ 0.191). Although the CS-FBD-J in the IBS group was significantly correlated with HADS-anxiety (r = 0.450) and depression scores (r = 0.357), their intercorrelations in the control group were not significant (r = 0.150 ~ 0.167). In the score comparison of the CS-FBD-J between the IBS patient group, non-patient IBS group (students with IBS except two who received treatment), and control group, there were significant group effects in the CS-FBD-J (IBS patient > non-patient IBS > control). The internal consistencies of the CS-FBD-J were high (α = 0.95). The item-total correlation analysis for the CS-FBD-J showed that the correlations between each item and the total score were significant.ConclusionThis study confirmed the reliability and validity of the 23-item version of the CS-FBS with the deletion of two items with low factor loadings.

Evaluation of plasma M2-Pyruvate Kinase as a novel biomarker in the differentiation between Functional and Organic Colonic Disorders

Background Differentiating between functional bowel disorders and organic colonic disorders can often be difficult as they may be present with similar symptoms. Aim of the Work to evaluate the diagnostic value of plasma M2-pyruvate kinase level in differentiating functional colonic disorders (e.g: IBS) from organic colonic disorders (e.g: IBD, colorectal polyps and colorectal cancer) and to assess its use as screening tools for inflammatory bowel disease, premalignant and malignant colorectal lesions. Patients and Methods This study was conducted on 80 patients who divided into four groups: Group I included 20 patients, representing functional bowel disorders (as a control group). Group II included 20 patients with inflammatory bowel diseases; Group III included 20 patients with colorectal polyps; Group IV included 20 patients with colorectal cancer. Results The current study showed that plasma M2 - PK can be used to differentiate functional from organic colonic lesions at a cut-off point > 3 U/mL, with 93.33% sensitivity, 100% specificity, 100% PPV and 83.3% NPV. Also, plasma M2-PK can be used to discriminate between benign (colorectal polyp) and malignant colonic lesions (CRC) with a cut-off level of > 12 U/ml, with 100% sensitivity, 100% specificity, 100% PPV and 100% NPV. Also, In the present study there was a highly significant + ve correlations between Plasma M2 PK level and CEA as (r = 0.787, p value = 0.000) and their combination can give higher sensitivity and specificity. Conclusion Plasma M2-PK can differentiate between functional and organic colonic disorders as it is more elevated in organic than functional colonic disorders. Also, it is considered a promising rapid noninvasive biomarker for organic colonic disorders early detection and screening to reduce unnecessary endoscopic intervention.

Obesity and functional bowel disorders in children

Obesity and functional bowel disorders (FBDs) are often observed in children and share common risk factors. However, the possible relationship between these conditions has begun to be studied recently and the results obtained are ambiguous. Therefore, it is important to summarize the literature on the relationship between obesity and FBDs in children and to discuss the possible pathophysiological mechanisms mediating this. The literature suggests that obesity and FBDs are likely associated conditions. A significant link between obesity and irritable bowel syndrome in children has been confirmed by all studies on this problem. There is also a many evidence that obesity in the pediatric cohort is associated with constipation. However, it should also be noted that there are few studies of this issue, they are heterogeneous in the composition of participants and the diagnostic criteria used, in most cases they are unadjusted for potential confounders. The link between obesity and FBDs may be mediated by diet, eating habits, and psychological factors. But the most promising direction in studying the association between these conditions may be studies of the gut microbiota, changes in which can contribute to impaired intestinal immune function, the development of chronic low-grade inflammation, increased intestinal permeability, impaired motility and visceral hypersensitivity. To date, there is insufficient data to confidently confirm the existence and nature of the relationship between obesity and FBDs in children, but research in this direction can provide important information for the development of approaches to treatment, prevention and early diagnosis of both groups of diseases.