Irritable Bowel Syndrome: What Treatments Really Work

Neurogastroenterology and motility disorders in patients with cirrhosis

Neurogastroenterology and motility disorders are complex gastrointestinal conditions that are prevalent worldwide, particularly affecting women and younger individuals. These conditions significantly impact the quality of life of people suffering from them. There is increasing evidence linking these disorders to cirrhosis, with a higher prevalence compared to the general population. However, the link between neurogastroenterology and motility disorders and cirrhosis remains unclear due to undefined mechanisms. In addition, managing these conditions in cirrhosis is often limited by the adverse effects of drugs commonly used for these disorders, presenting a significant clinical challenge in the routine management of patients with cirrhosis. This review delves into this connection, exploring potential pathophysiological links and clinical interventions between neurogastroenterology disorders and cirrhosis.

Efficacy of linaclotide in combination with polyethylene glycol for bowel preparation in Chinese patients undergoing colonoscopy polypectomy: protocol for a randomised controlled trial

BACKGROUND

Adequate bowel preparation is essential for successful colonoscopy and polypectomy procedures. However, a significant proportion of patients still exhibit suboptimal bowel preparation, ranging from 18% to 35%. The effectiveness of bowel preparation agents can be hampered by volume and taste, adversely affecting patient compliance and tolerance. Therefore, exploring strategies to minimise laxative volume and improve patient tolerance and adherence is imperative to ensure optimal bowel preparation quality.

METHODS AND ANALYSIS

This study is a two-arm, single-blinded, parallel-group randomised controlled trial designed to compare the efficacy of 2 L polyethylene glycol (PEG) combined with linaclotide with 4 L PEG in bowel cleansing. A total of 422 participants will be randomly assigned in a 1:1 ratio to either the intervention group (2 L PEG combined with 580 µg linaclotide) or the control group (4 L PEG). The primary outcome measure is bowel cleansing efficacy, which is assessed using the Boston Bowel Preparation Scale. Secondary outcomes include evaluating the tolerability and safety of the bowel preparation regimens, bowel diary assessments, postpolypectomy complications (such as bleeding and perforation) and the size and number of removed polyps.

ETHICS AND DISSEMINATION

The study has received approval from the Clinical Research Ethics Committee of The First Affiliated Hospital, Zhejiang University School of Medicine. The findings of this trial will serve as a valuable resource for clinicians and patients undergoing colonoscopy polypectomy by guiding the selection of appropriate bowel preparation regimens. Study findings will be disseminated to participants, presented at professional society meetings, and published in peer-reviewed journals. This trial was registered on the Chinese Clinical Trial Registry with registration number ChiCTR2300075410.

Effect of the combined intervention of low-FODMAPs diet and probiotics on IBS symptoms in Western China: A randomized controlled trial

The effect of low-FODMAPs diet on irritable bowel syndrome (IBS) in Western China has not been reported. We aimed to investigate the effect of low-FODMAPs diet on IBS patients in the area and whether low-FODMAPs diet-induced alterations of microbiota could be improved through probiotics. IBS patients were randomized to the control group, low-FODMAPs diet group, probiotics group, or combined group. IBS Symptom Severity Score questionnaire (IBS-SSS) and IBS Quality of Life Score questionnaire (IBS-QOL) were completed at baseline, 2 and 4 weeks to evaluate the severity of symptoms. Fresh feces were collected for analyses of gut microbiota and short-chain fatty acids at baseline and 4 weeks after intervention. Seventy-three patients were included in the per protocol analysis. After intervention, there was significant improvement in IBS-SSS in the low-FODMAPs group (37.5%, 44.2%), probiotics group (51.4%, 62.0%), and combined group (34.1%, 40.4%) at both 2 weeks and 4 weeks, compared with the baseline (p < .05). In the low-FODMAPs group, the abundance of several microbiota (Lachnoclostridium, Enterococcus, etc.) was significantly decreased. Furthermore, after the supplementation of probiotics in the combined group, the abundance of Genus_Ruminococcus, Coprococcus, Acidaminococcus, Ruminiclostridium, Akkermansia, Eggerthella, and Oxalobacter was significantly increased, which was associated with the improvements of symptoms score in the Pearson correlation analysis. Our study confirmed the effectiveness and safety of short-term low-FODMAPs diet in IBS symptoms based on the Chinese diet in Western China. The combination of low-FODMAPs and probiotics plays a beneficial role in gut microbiota in IBS.

Exploring the clinical significance of miR-148 expression variations in distinct subtypes of irritable bowel syndrome

Irritable bowel syndrome (IBS) belongs to chronic functional gastrointestinal diseases featured by abdominal pain and changes in bowel habits. This study aimed to investigate the clinical significance of serum miR-148 expression in different subtypes of IBS. We enrolled 86 IBS patients and 55 healthy controls. miR-148 expression levels were assessed in IBS patients classified into IBS-constipation (IBS-C), IBS-diarrhea (IBS-D), and IBS-mixed stool pattern (IBS-M) subtypes. Receiver-operating characteristic (ROC) curves were employed to evaluate the diagnostic potential of miR-148 in distinguishing among IBS subtypes. Additionally, we analyzed the correlation between miR-148 expression and clinical characteristics, including IBS symptom severity. miR-148 expression was highest in IBS-D (diarrhea) group, followed by IBS-M and IBS-C. With the exception of the IBS-C group, miR-148 expression was elevated in IBS patients compared to controls. ROC curve analysis demonstrated that serum miR-148 exhibited higher diagnostic accuracy for discriminating IBS-C and IBS-D than IBS-M. Correlation analysis revealed a positive relationship between serum miR-148 relative expression and IBS symptom severity system scores. Univariate logistic analysis indicated a positive association between miR-148 expression and IBS-D and a negative correlation with IBS-C. miR-148 expression exhibits differential patterns among IBS subtypes and holds a potential to distinguish IBS-C and IBS-D. Furthermore, miR-148 expression correlates with the severity of IBS symptoms.

Evaluation of the Efficacy of Kombucha-Based Drink Enriched with Inulin and Vitamins for the Management of Constipation-Predominant Irritable Bowel Syndrome in Females: A Randomized Pilot Study

Background

Constipation-predominant irritable bowel syndrome (IBS-C) mainly affects females, and dietary interventions for symptom relief often yield poor results because of low patient adherence. The development of functional food products enriched with dietary fibers may increase patients' adherence to a healthy diet and relieve IBS-С symptoms.

Objective

This proof-of-concept, open-label, randomized controlled pilot study is aimed to evaluate the efficacy of kombucha enriched with inulin and vitamins in females with IBS-C.

Methods

Forty females with IBS-C were randomly assigned to receive either 220 mL of kombucha enriched with inulin (2.53 g/220 mL) and vitamins (B1 - 0.59 mg, B2 - 0.55 mg, B3 - 5.9 mg, B6 - 0.7 mg, and folic acid - 81.4 μg/220 mL) or water for 10 d. Stool frequency, Bristol stool scale score (BSSS), and abdominal symptoms were evaluated using a 5-point Likert scale on days 5, 9 and 14 of the study. The palatability of the drink was assessed using a visual analog scale.

Results

After 10 d, the kombucha group showed a significant increase in stool frequency (0.60 ± 0.31-0.85 ± 0.19 times/d; P = 0.004) compared with the control (0.63 ± 0.33 compared with 0.72 ± 0.28; P = 0.6). The mean values of the BSSS increased in the kombucha group (3.0 ± 1.2-4.4 ± 1.0; P = 0.001), whereas they remained unchanged in the control (2.9 ± 1.2 compared with 3.4 ± 1.2; P = 0.6). The kombucha group also experienced a significant decrease in the feeling of incomplete bowel emptying (1.88 ± 0.78 compared with 1.41 ± 0.56 points; P = 0.015), which was not observed in the control group.

Conclusions

Short-term consumption of kombucha enriched with inulin and vitamins was associated with an increase in stool frequency, an improvement in the BSSS, and a reduction in the feeling of incomplete bowel emptying in females with IBS-C. Further large-scale clinical trials investigating the efficacy of kombucha enriched with inulin and vitamins in patients with IBS-C are warranted to prove the observed effects.

Trial registration number

This trial was registered at clinicaltrials.gov as NCT05164861 (==https://clinicaltrials.gov/study/NCT05164861?term=NCT05164861&rank=1; registered on 18 December, 2021).

The Importance of Visceral Hypersensitivity in Irritable Bowel Syndrome-Plant Metabolites in IBS Treatment

The visceral stimuli from the digestive tract are transmitted via afferent nerves through the spinal cord to the brain, where they are felt as pain. The overreaction observed in the brain of irritable bowel syndrome (IBS) patients may be due to increased peripheral sensitivity to stimuli from the gastrointestinal tract. Although the exact pathway is uncertain, attenuation of visceral hypersensitivity is still of interest in treating IBS. It has been shown that stress stimulates the sympathetic nervous system while inhibiting the vagus nerve (VN). In addition, stress factors lead to dysbiosis and chronic low-grade inflammation of the intestinal mucosa, which can lead to lower gastrointestinal visceral hypersensitivity. Therefore, an important goal in the treatment of IBS is the normalization of the intestinal microflora. An interesting option seems to be nutraceuticals, including Terminalia chebula, which has antibacterial and antimicrobial activity against various pathogenic Gram-positive and Gram-negative bacteria. Additionally, short-term transcutaneous vagus nerve stimulation can reduce the stress-induced increase in intestinal permeability, thereby reducing inflammation. The conducted studies also indicate a relationship between the stimulation of the vagus nerve (VN) and the activation of neuromodulatory networks in the central nervous system. Therefore, it seems reasonable to conclude that a two-way action through stimulating the VN and using nutraceuticals may become an effective therapy in treating IBS.

Causal association between psycho-psychological factors, such as stress, anxiety, depression, and irritable bowel syndrome: Mendelian randomization

BACKGROUND

Pathogenesis, diagnosis, and treatment of irritable bowel syndrome (IBS) have been reported to be challenging hotspots in clinical practice. Previous observational studies have found that stress, anxiety, depression, and other mental and psychological diseases are closely associated with IBS. This study aimed to further explore the causal relationships of these associations through Mendelian randomization (MR).

METHODS

The data needed for MR were obtained from publicly published genome-wide association databases. We performed a bidirectional, 2-sample MR analysis using instrumental variables (IV) associated with stress, anxiety, and depression, and other mental and psychological factors as exposures and IBS as the outcome. A reverse MR analysis with IBS as exposure and stress, anxiety, depression, and other mental and psychological factors as the outcomes was also performed. The inverse variance weighting (IVW) method was adopted as the main method of MR, and the causal effect between stress, anxiety, depression, and other mental and psychological factors and IBS was evaluated as the main result of the study. In addition, a series of sensitivity analyses was conducted to comprehensively evaluate the causal relationship between them.

RESULTS

Stress, anxiety, depression, and other mental and psychological factors were the underlying etiologies for IBS (odds ratio [OR] = 1.06, 95% confidence interval [CI]: 1.03-1.08), and they were positively correlated. Univariate analysis further supported the above conclusions (Depression, [OR = 1.31, 95% CI: 1.05-1.63, P = .016], Anxiety, [OR = 1.53, 95% CI: 1.16-2.03, P = .003]). However, in reverse MR analysis, we found that IBS did not affect stress, anxiety, depression, or other mental and psychological factors and that there was no causal relationship between IBS and stress, anxiety, depression, or other mental and psychological factors (P > .05).

CONCLUSION

This study demonstrates that mental and psychological factors are the underlying etiologies for IBS. These findings may provide important information for physicians regarding the clinical treatment of IBS.

Irritable Bowel Syndrome and Resilience

Irritable bowel syndrome (IBS) is a disorder of the gut-brain interaction (DGBI), characterized, mainly in severe cases, by altered psychological stress reactivity, psychological disorders, and dysfunction of the brain-gut-microbiota axis. Prior studies have highlighted significant physical and emotional impairments in the health-related quality of life of patients with IBS. Resilience is a psychosocial ability that reduces negative emotions while enhancing adaptation to adversities. Resilience is essential for health promotion and stress response. The present study aimed to carry out a review of the literature in multiple databases, using the descriptors "resilience", "resiliency", and "irritable bowel syndrome". The inclusion criteria for obtaining the most relevant papers were research articles on resilience and irritable bowel syndrome written in English, published in a peer-reviewed journal, and involving human subjects. Studies specifically on resilience in IBS were sparse. These results need to be understood in light of these limitations. As resilience appears to be modifiable, it is essential to conduct direct research on resilience-enhancing interventions for people with IBS. The study of the factors involved in successful adaptation must be extended, to possibly yield new interventions that help the patients overcome the difficulties imposed by the disease.

Network pharmacology and molecular docking reveal the immunomodulatory mechanism of rhubarb peony decoction for the treatment of ulcerative colitis and irritable bowel syndrome

Background: Ulcerative colitis (UC) and irritable bowel syndrome (IBS) share various similarities in clinical symptoms, pathogenesis, and treatment. UC concurrent IBS tends toward more severe symptoms and worse prognosis, and promising feasible therapies for the overlapping symptoms remains a challenge. Rhubarb peony decoction (RPD) is a well-known traditional Chinese medicine that has been widely applied in treating UC. RPD may exert extensive therapeutic effects on both IBS and UC. However, the common mechanism of its treatment remains unclear. We aimed to assess the potential pharmacological mechanism of RPD in the treatment of overlapping IBS and UC. Methods: The active components and targets of RPD were retrieved from ETCM, TCMSP, BATMAN-TCM, and TCM databases. The disease targets were screened by searching the DrugBank, OMIM, TTD, and PharmGKB databases. PPI network analysis was performed and visualized via the STRING platform and Cytoscape software. GO and KEGG enrichment analyses of the hub genes of RPD were predicted to elucidate the potential molecular mechanism. Subsequently, molecular docking was carried out to verify the combination of active compounds with core targets. Results: By integrating all targets of RPD and disease, a total of 31 bioactive ingredients were identified including quercetin, kaempferol, aloe-emodin, beta-sitosterol, and (+)-catechin, etc. JUN, TP53, MAPK1, RELA, MYC, and ESR1 were explored as potential therapeutic targets among 126 common drug-disease-related targets. They were enriched in the AGE-RAGE signaling pathway in diabetic complications, as well as the NF-kappa B signaling pathway and MAPK signaling pathway. Additionally, some active ingredients were identified as candidates for binding to the hub targets via molecular docking, further suggesting their anti-inflammatory and antioxidative properties. Conclusion: RPD may exert the overall treatment effect for UC and IBS overlap syndrome via the biological mechanism of "multi-ingredients, multi-targets, and multi-pathways" on inflammation, oxidative stress, immune, oncogenicity, and gut microbiota dysbiosis.

Constipation-Predominant Irritable Bowel Syndrome (IBS-C): Effects of Different Nutritional Patterns on Intestinal Dysbiosis and Symptoms

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder characterized by abdominal pain associated with defecation or a change in bowel habits. The pathogenesis of IBS is not completely clear, but it is known to be multifactorial and complex. Endogenous and exogenous factors such as abnormal GI motility, low-grade inflammation, increased epithelial permeability and visceral hypersensitivity, but diet and psychosocial aspects are also recognized as important actors. Furthermore, the interaction between diet and gut microbiota has gained interest as a potential contributor to the pathophysiology of IBS. To date, there is no specific diet for IBS with constipation (IBS-C); however, many studies show that fiber intake, especially soluble fiber such as inulin, could have a positive effect on symptoms. This review aims to evaluate the effects of some nutritional components such as fibers but also functional foods, prebiotics, probiotics and symbiotics on symptoms and microbiota in IBS-C subjects.

Biomarkers for Bile Acid Malabsorption in Diarrhea-predominant Irritable Bowel Syndrome: A Systematic Review and Meta-analysis

BACKGROUND AND AIM

A clear relationship of biological indexes between bile acid malabsorption (BAM) and diarrhea-predominant irritable bowel syndrome (IBS-D) has not been well analyzed. This meta-analysis aimed to establish a more convenient method to diagnose BAM in IBS-D patients by comparing the differences in biomarkers between IBS-D patients and healthy people.

METHODS

Multiple databases were searched for relevant case-control studies. Indicators used to diagnose BAM included 75Se-homocholic acid taurine (SeHCAT), 7α-hydroxy-4-cholesten-3-one(C4), fibroblast growth factor-19 and 48-hour fecal bile acid (48FBA). The rate of BAM (SeHCAT) was calculated by using a random-effect model. The levels of C4, FGF19, and 48FBA were compared, and the overall effect size was combined by a fixed effect model.

RESULTS

The search strategy identified 10 relevant studies comprising 1034 IBS-D patients and 232 healthy volunteers. The pooled rate of BAM in IBS-D patients was 32% (according to SeHCAT; 95% CI: 24%-40%). The level of C4 in IBS-D patients was significantly higher than that in the control group (2.86 ng/mL; 95% CI: 1.09, 4.63); The level of FGF19 was significantly lower than that in the control group (-33.97 pg/mL; 95% CI: -51.13, -16.82); The level of 48FBA was significantly higher than that in the control group (0.059; 95% CI: 0.41, 0.77).

CONCLUSIONS

The results mainly concluded serum C4 and FGF19 levels in IBS-D patients. Most of the studies have different normal cutoff points of serum C4 and FGF19 levels; the performance of each test should be further estimated. By comparing the levels of these biomarkers, BAM in patients with IBS-D could be identified more accurately, which would lead to more effective treatment.

Regulation of the central amygdala on intestinal motility and behavior via the lateral hypothalamus in irritable bowel syndrome model mice

BACKGROUND

Impaired bidirectional communication between the gastrointestinal tract and the central nervous system (CNS) is closely related to the development of irritable bowel syndrome (IBS). Studies in patients with IBS have also shown significant activation of the hypothalamus and amygdala. However, how neural circuits of the CNS participate in and process the emotional and intestinal disorders of IBS remains unclear.

METHODS

The GABAergic neural pathway projecting from the central amygdala (CeA) to the lateral hypothalamus (LHA) in mice was investigated by retrograde tracking combined with fluorescence immunohistochemistry. Anxiety, depression-like behavior, and intestinal motility were observed in the water-immersion restraint stress group and the control group. Furthermore, the effects of the chemogenetic activation of the GABAergic neural pathway of CeA-LHA on behavior and intestinal motility, as well as the co-expression of orexin-A and c-Fos in the LHA, were explored.

KEY RESULTS

In our study, Fluoro-Gold retrograde tracking combined with fluorescence immunohistochemistry showed that GABAergic neurons in the CeA were projected to the LHA. The microinjection of the gamma-aminobutyric acid (GABA) receptor antagonist into the LHA relieved anxiety, depression-like behavior, and intestinal motility disorder in the IBS mice. The chemogenetic activation of GABAergic neurons in the CeA-LHA pathway led to anxiety, depression-like behavior, and intestinal motility disorder. In addition, GABAergic neurons in the CeA-LHA pathway inhibited the expression of orexin-A in the LHA, and orexin-A was co-expressed with GABAA receptors.

CONCLUSIONS & INFERENCES

The CeA-LHA GABAergic pathway might participate in the occurrence and development of IBS by regulating orexin-A neurons.

Chaihu-Guizhi-Ganjiang Decoction is more efficacious in treating irritable bowel syndrome than Dicetel according to metabolomics analysis

BACKGROUND

Chaihu-Guizhi-Ganjiang Decoction (CGGD) is a traditional Chinese medicine (TCM) prescription used to treat viral influenza. There is evidence that CGGD can be used to treat irritable bowel syndrome (IBS) but the potential mechanism of action and metabolites produced upon CGGD treatment remains elusive.

METHODS

Patients with IBS were treated with pinaverium bromide (Dicetel™) and then CGGD after a washout period of 1 week. Both treatments lasted for 30 days. The efficacy and changes of metabolites in plasma after the two treatments were compared. Plasma samples were acquired before and after each treatment, and untargeted metabolics analysis was performed.

RESULTS

Efficacy was measured according to the Rome IV criteria and TCM theory. Our results indicated that CGGD showed significantly better efficacy than Dicetel in the treatment of IBS utilizing each criterion. CGGD exerted greater effects on plasma metabolism than Dicetel. Dicetel treatment led to increased tryptophan metabolism (increased levels of 5-Hydroxyindoleacetaldehyde) and increased protein metabolism (increased levels of L-arginine). CGGD treatment significantly (p < 0.05) increased carnitine metabolism, with elevated levels of L-carnitine and acylcarnitine in plasma. Such changes in these metabolites could exert effects against IBS by improving gastrointestinal motility and suppressing pain, depression, and inflammation.

CONCLUSIONS

CGGD appeared to be more efficacious than Dicetel for treating patients with IBS. The findings provide a sound support for the underlying biomolecular mechanism of CGGD in the prevention and treatment of IBS.

Development and validation of a highly sensitive and selective LC-MS/MS method for the determination of 15-hydroxylubiprostone in human plasma: Application to a pharmacokinetic study in healthy Chinese volunteers

Lubiprostone, a derivative of prostaglandin E1, is the first chemical-type constipation treatment approved by FDA. Lubiprostone has low systemic exposure after oral administration. Therefore, it is recommended that 15-hydroxylubiprostone, which is a dominant active metabolite of lubiprostone, be used as the pharmacokinetic evaluation indicator. Due to the microdosage of the lubiprostone capsules, it is difficult to develop a highly sensitive bioanalytical method for 15-hydroxylubiprostone.In this study, a highly sensitive and selective liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method has been established and fully validated for the quantification of 15-hydroxylubiprostone in human plasma, and the validated bioanalytical method has been applied to a pharmacokinetic study of lubiprostone capsules successfully.The pharmacokinetics of 15-hydroxylubiprostone were observed after fed administration in healthy Chinese volunteers. The C_max and AUC_0-t were 75.8 ± 57.6 pg/mL and 222 ± 68.0 pg·h/mL for 15-hydroxylubiprostone.This study investigated the pharmacokinetic properties of 15-hydroxylubiprostone under fed conditions in healthy Chinese volunteers and would provide clinical guidance for the application and further development of lubiprostone capsules.

The effect of self-management online modules plus nurse-led support on pain and quality of life among young adults with irritable bowel syndrome: A randomized controlled trial

BACKGROUND

Irritable bowel syndrome is a chronic pain condition that needs life-long self-management. However, the effect of self-management among young adults with irritable bowel syndrome is limited.

OBJECTIVES

This study aimed to examine the effect of a nurse-led self-management program on pain, symptoms, and quality of life among young adults with irritable bowel syndrome.

DESIGN

A randomized controlled trial.

SETTINGS AND PARTICIPANTS

Eighty young adults with irritable bowel syndrome recruited from two campuses of a public university and two gastrointestinal clinics were randomly assigned into a self-management online education and learning modules alone group (Online Modules, n = 41) or a nurse-led one-to-one consultation plus self-management online education and learning modules group (Nurse-Led Online Modules, n = 39). Twenty-one healthy controls were also recruited from these two campuses.

METHODS

Both the intervention groups received ten online modules after baseline data collection. Participants in the Nurse-Led Online Modules group received additional three nurse-led one-to-one consultations at baseline, 6- and 12-week follow-ups. Self-reported pain, symptoms, quality of life, self-efficacy for managing chronic disease, and coping were measured at baseline, and 6- and 12-week follow-ups among the participants with irritable bowel syndrome. The healthy controls completed data collection of pain and symptoms at baseline and the 12-week follow-up. The intervention effects across study time points and the comparisons between the two interventional groups were analyzed using linear mixed models. A longitudinal mediation analysis was also conducted to explore the mediation effects of self-management mechanisms of the interventions.

RESULTS

Both the intervention groups showed significant interventional effects on decreasing pain intensity and pain interference and increasing quality of life at the 12-week follow-up (all p < 0.05). At the 12-week follow-up, the Nurse-Led Online Modules significantly reduced anxiety (p = 0.016) and had a significant greater improvement in quality of life than the Online Modules (p = 0.040). Increased self-efficacy mediated the intervention effect of the Nurse-Led Online Modules group on reducing pain interference and improving quality of life, while the effect of the Online Modules was mediated through decreasing inefficient coping strategy-catastrophizing.

CONCLUSIONS

This study showed that both the pain self-management online education and nurse-led intervention were effective for alleviating pain and improving quality of life among young adults with irritable bowel syndrome by targeting the self-management process. The nurse-led intervention had a better outcome than the online education alone in improving quality of life.

REGISTRATION NUMBER

NCT03332537.

NUCB2/Nesfatin-1 Regulation of Chronic Visceral Hyperalgesia

Objective

We previously described that different concentration Nucleobindin-2 (NUCB2)/Nesfatin-1 gradients differently regulated visceral hypersensitivity in irritable bowel syndrome. Therefore, this study is aimed at evaluating the effect of NUCB2/Nesfatin-1 on model rats with chronic visceral hyperalgesia.

Methods

Neonatal and mature Sprague-Dawley rats were randomly divided into the healthy control and chronic visceral hyperalgesia model groups. The model was built by combining maternal separation with the acetic acid enema. The models were identified by the distension volume threshold to reach abdominal withdraw reflex (AWR) score = 3, histological staining, and myeloperoxidase (MPO) detection. The visceral sensitivity to chronic visceral hyperalgesia was then evaluated.

Result

Rats in the model group responded more strongly to pulling stimulation than healthy controls; the distension volume threshold causing AWR3 response in model rats was lower than the control group before NUCB2/Nesfatin-1 intervention. After intervention, the distension volume threshold was significantly lower in the NUCB2/Nesfatin-1 central intervention group than in the NUCB2/Nesfatin-1 peripheral intervention group, and the peak value of external oblique muscle electrical activity was significantly higher. Additionally, compared with the male intervention group, in the female intervention group, the volume threshold was significantly lower and the peak value was higher.

Conclusion

NUCB2/Nesfatin-1 could regulate visceral sensitivity in chronic visceral hyperalgesia model rats; its regulatory effect correlated with the type of NUCB2/Nesfatin-1 intervention approaches (central or peripheral) and sex (male or female).

The relationship between gut microbiota and proteolytic activity in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disease that affects 3.8-9.2% of the world population. It affects the physiology and psychology of patients and increases the burden on families, the healthcare system, society, and economic development. Presently, a large number of studies have shown that compared to healthy individuals, the composition and diversity of gut microbiota in IBS patients have changed, and the proteolytic activity (PA) in fecal supernatant and colonic mucosa of IBS patients has also increased. These findings indicate that the imbalance of intestinal microecology and intestinal protein hydrolysis is closely related to IBS. Furthermore, the intestinal flora is a key substance that regulates the PA and is associated with IBS. The current review described the intestinal microecology and intestinal proteolytic activity of patients with IBS and also discussed the effect of intestinal flora on PA. In summary, this study proposed a pivotal role of gut microbiota and PA in IBS, respectively, and provided an in-depth insight into the diagnosis and treatment targets of IBS as well as the formulation of new treatment strategies for other digestive diseases and protease-related diseases.

Transcranial direct current stimulation relieves visceral hypersensitivity via normalizing GluN2B expression and neural activity in anterior cingulate cortex

Irritable bowel syndrome (IBS) is one of the most common challenging diseases for clinical treatment. The aim of this study is to investigate whether transcranial direct current stimulation (tDCS) has analgesic effect on visceral hypersensitivity (VH) in an animal model of IBS as well as the underlying mechanism. As the activation of GluN2B in anterior cingulate cortex (ACC) takes part in VH, we examined whether and how GluN2B in ACC takes part in the effect of tDCS. Neonatal maternal deprivation (NMD), a valuable experimental model to study the IBS pathophysiology, was used to induce visceral hypersensitivity of rats. We quantified VH as colorectal distention threshold and performed patch-clamp recordings of ACC neurons. The expression of GluN2B were determined by RT-qPCR and Western blotting. The GluN2B antagonist Ro 25-6981 was microinjected into the rostral and caudal ACC. tDCS was performed for 7 consecutive days. It was found that NMD decreased expression of GluN2B, which could be obviously reversed by tDCS. Injection of Ro 25-6981 into rostral and caudal ACC of normal rats induced VH and also reversed the analgesic effect of tDCS. Our data sheds light on the nonpharmacological therapy for chronic VH in pathological states such as IBS.NEW & NOTEWORTHY Irritable bowel syndrome (IBS) is a gastrointestinal disease characterized by visceral hypersensitivity. This study showed a decrease of GluN2B expression and neural activity in ACC of IBS-model rats, which could be obviously reversed by tDCS. In addition, blockade of GluN2B in rostral and caudal ACC induced VH of normal rats. Furthermore, analgesic effect of tDCS on NMD rats was reversed by GluN2B antagonist.

Diarrhea Predominant-Irritable Bowel Syndrome (IBS-D): Effects of Different Nutritional Patterns on Intestinal Dysbiosis and Symptoms

Irritable Bowel Syndrome (IBS) is a chronic functional gastrointestinal disorder characterized by abdominal pain associated with defecation or a change in bowel habits. Gut microbiota, which acts as a real organ with well-defined functions, is in a mutualistic relationship with the host, harvesting additional energy and nutrients from the diet and protecting the host from pathogens; specific alterations in its composition seem to play a crucial role in IBS pathophysiology. It is well known that diet can significantly modulate the intestinal microbiota profile but it is less known how different nutritional approach effective in IBS patients, such as the low-FODMAP diet, could be responsible of intestinal microbiota changes, thus influencing the presence of gastrointestinal (GI) symptoms. The aim of this review was to explore the effects of different nutritional protocols (e.g., traditional nutritional advice, low-FODMAP diet, gluten-free diet, etc.) on IBS-D symptoms and on intestinal microbiota variations in both IBS-D patients and healthy subjects. To date, an ideal nutritional protocol does not exist for IBS-D patients but it seems crucial to consider the effect of the different nutritional approaches on the intestinal microbiota composition to better define an efficient strategy to manage this functional disorder.

Dietary interventions and irritable bowel syndrome - what really works?

PURPOSE OF REVIEW

The review examines the latest research on the use of dietary interventions in the management of irritable bowel syndrome (IBS) in order to understand what is the evidence supporting the efficacy of a dietary approach in this disorder.

RECENT FINDINGS

A general dietary advice should be offered to all IBS patients. Psyllium supplementation is recommended in IBS with both constipation and diarrhea predominance. There is increasing evidence showing the beneficial effects of a low fermentable oligo-, di-, monosaccharides, and polyols (FODMAP) diet (LFD) on IBS symptoms. FODMAPs that are well tolerated should be reintroduced in daily diet, to increase acceptability of the diet, and limit potentially harmful effects. The benefits observed with the gluten-free diet seem determined by the reduction of FODMAPs rather than gluten. Modulation of gut microbiota using probiotics shows promising results, but there are unanswered questions regarding the optimal strains, dose and duration of treatment. Additional evidence is also needed for the role of prebiotics and synbiotics in IBS.

SUMMARY

Food is both trigger of IBS symptoms and therapeutic tool. Recent studies demonstrated the beneficial effects of LFD on symptom control, as well as the role of probiotics, which seem to contribute to gut health and function.

Lipi Guben decoction in treating diarrheal irritable bowel syndrome: A study protocol for a randomized controlled trial

BACKGROUND

Irritable bowel syndrome (IBS) is a common functional bowel disorder. The global incidence of IBS is as high as 9% to 23%, accounting for about 50% of outpatients in gastroenterology, and the new case detection rate is 0.2% every year. IBS has become a global gastrointestinal functional disease. Although IBS is not a life-threatening disease, it seriously affects the quality of life of patients, causing huge economic and mental burden to individuals, society and families. Lipi Guben decoction (LPGBD) is an important auxiliary treatment for IBS, but lack of robust Evidence-based medicine evidence proving its efficacy. Therefore, we designed a randomized controlled trial to evaluate the efficacy and safety of LPGBD in the treatment of IBS.

METHODS

In this randomized controlled trial, a total of 100 eligible patients will be allocated to the blank control group or LPGBD group in a ratio of 1:1. The treatment period was 12 weeks. The primary outcome measure will be the total clinical effective rate. The Secondary outcomes will include IBS clinical symptom scores, IBS-Severity Scoring System, IBS-Quality of life, Hamilton Rating Scale for Anxiety, Hamilton Rating Scale for Depression, and Bristol Stool Form Scale. The safety outcome will include Echocardiogram, blood examination (including blood routine test, liver function test, and renal function test), urine routine test and stool routine test. The evaluation indicators and all safety results will be performed at baseline, week 4, week 8 and week 12.

RESULTS

This study will be helpful to evaluate the efficacy and safety of LPGBD in the treatment of IBS.

CONCLUSION

LPGBD may improve the clinical efficacy of patients with IBS, which has important value in practical application.

TRIAL REGISTRATION

Chictr20000039617, registration time: November 3, 2020.

Prevalence of Irritable Bowel Syndrome and Frequency of Symptoms in the General Population of Pakistan

INTRODUCTION

Irritable bowel syndrome (IBS) is a chronic and debilitating functional gastrointestinal disorder. Risk factors include infective enteritis, female sex, antibiotic exposure, anxiety, and depression. The aim of this study is to find out the prevalence of IBS in healthy population and determine the characteristics of symptoms.

MATERIAL AND METHODS

A cross-section study was conducted in the internal medicine unit of a tertiary care hospital in multiple cities of Pakistan. Eight hundred (800) healthy peoples were selected for study from June 2019 to August 2019. Diagnosis of IBS was made by using Rome III criteria.

RESULTS

The prevalence of irritable bowel syndrome (IBS) in general population in our study was 33.2%. IBS was more common in females compared to males (57.7% vs. 42.2%; p value = 0.009). IBS was more common in age group between 20 and 29 years (45.5%). Among patient diagnosed with IBS in this study, the most common was bloating (74.7%) followed by increased stool frequency (54.4%).

CONCLUSION

IBS is very prevalent in Pakistan, yet there is very little data and awareness related to it. Any change in stool frequency or consistency in young adults, especially women, shall be evaluated for IBS after ruling out other diseases. Early diagnosis and treatment of IBS will assist in improving the patient's quality of life.

Recent advances in the pharmacological management of constipation predominant irritable bowel syndrome

Introduction: Irritable bowel syndrome (IBS) is a complex functional gut disorder that typically manifests in early adult years. More than a third of IBS patients are diagnosed with predominant constipation subtype (IBS-C). This syndrome has a distressing impact on the quality of life and is challenging both for patients and physicians.Areas covered: This review focuses on the pathophysiology of constipation in IBS and presents current management options. It also covers the latest findings that may lead to novel pharmacological options in IBS-C management. The authors intend to highlight the results of published research including abstracts, records from the clinicaltrials.gov database (second and third phases of the study) and information from original FDA documents.Expert opinion: Current therapeutic options for IBS-C treatment are based on linaclotide, lubiprostone, plecanatide, and the reintroduced tegaserod. Drugs present on the market as well as those in pre-clinical development should increase the lower esophageal sphincter pressure, promote gastric motility, accelerate gastric emptying and improve gastro-duodenal coordination. Most significantly, they shall not induce severe side effects.

Irritable bowel syndrome: how can symptoms and quality of life be improved with diet?

PURPOSE OF REVIEW

This article aims to review the current scientific evidence of dietary approaches to control the symptoms of irritable bowel syndrome (IBS).

RECENT FINDINGS

In the last decade, there was an important evolution in the study of the low fermentable oligo, di, mono-saccharides and polyols (FODMAP) diet (LFD). Current scientific evidence suggests a significant efficacy in the overall control of symptoms. LFD seems to be effective in improving quality of life. Recent studies suggest that LFD is effective and nutritionally well tolerated also in the long term, and longer adherence may contribute to greater effectiveness in improving depression. There is insufficient scientific evidence for the recommendation of gluten exclusion in IBS therapy, and some authors still suggest that the efficacy of this approach results from the limited ingestion of fructans. There is a promising efficacy of pre, pro, and symbiotic supplements, but there is no consensus on the most appropriate and effective strains in each case.

SUMMARY

Given the poor evidence and the pathophysiological variability of IBS, the interest of each therapeutic option should be always evaluated individually. Nevertheless, LFD is currently the dietary approach with a higher degree of scientific evidence.

Gastrointestinal motility and absorptive disorders in patients with inflammatory bowel diseases: Prevalence, diagnosis and treatment

Inflammatory bowel diseases (IBD), Crohn`s disease and ulcerative colitis, are chronic conditions associated with high morbidity and healthcare costs. The natural history of IBD is variable and marked by alternating periods of flare and remission. Even though the use of newer therapeutic targets has been associated with higher rates of mucosal healing, a great proportion of IBD patients remain symptomatic despite effective control of inflammation. These symptoms may include but not limited to abdominal pain, dyspepsia, diarrhea, urgency, fecal incontinence, constipation or bloating. In this setting, commonly there is an overlap with gastrointestinal (GI) motility and absorptive disorders. Early recognition of these conditions greatly improves patient care and may decrease the risk of mistreatment. Therefore, in this review we describe the prevalence, diagnosis and treatment of GI motility and absorptive disorders that commonly affect patients with IBD.

Pseudo-obstruction, enteric dysmotility and irritable bowel syndrome

New diagnostic techniques have advanced our knowledge about the irritable bowel syndrome. The majority of patients that we believed to have a psychosomatic disorder have received other diagnoses explaining their symptoms. Endoscopy makes it possible to diagnose celiac disease before it leads to malnutrition and allows the detection of microscopic colitis as a cause of watery diarrhea. At the severe end of the symptom spectrum enteric dysmotility marks the border at which IBS ceases to be a functional disorder and becomes a genuine motility disorder. Joint hypermobility or Ehlers-Danlos syndrome is present in a substantial proportion of patients with enteric dysmotility. Chronic intestinal pseudo-obstruction is the end-stage of a large number of very rare disorders in which failed peristalsis is the common denominator. Nutritional needs and symptom control are essential in the management of pseudo-obstruction. Home parenteral nutrition is life saving in more than half of patients with chronic intestinal pseudo-obstruction.