Targets In Irritable Bowel Syndrome Research Articles

Mechanism of the Treatment of Irritable Bowel Syndrome with Sini Powder and Tong Xie Yao Fang Decoction Based on Network Pharmacology

This study used a network pharmacology approach to investigate the potential active ingredients of Sini Powder and Tong xie yao fang decoction and the underlying mechanisms in irritable bowel syndrome (IBS) treatment. The potential active ingredients of Sini Powder and Tong xie yao fang decoction were obtained from TCMSP databases, and the potential targets of the active ingredients were predicted and analyzed by using the Swiss Target Prediction database. T Genecard, DisGeNET, and OMIM databases were processed to screen the potential therapeutic targets in IBS. The interaction of overlapped candidates between the potential biotarget of herb extracts and the potential therapeutic target of IBS were analyzed by STRING website and visualized by the Cytoscape V3.8.0 software. Gene ontology (GO) analysis and Kyoto Genomics and Genomics Encyclopedia (KEGG) pathway were processed to categorize and map the potential biofunctions and effects of these candidates by using David database. Result. There were 139 predicted active components and 248 related biotargets of Sini Powder and Tong xie yao fang decoction which were involved in IBS treatment, and 522 annotations and 101 related pathways are obtained by enrichment analysis (P < 0.01, FDR < 0.05). The underlying mechanisms of Sini Powder and Tong xie yao fang decoction may be related to neuroactive ligand-receptor interaction, calcium, cAMP, and HIF-1 signaling pathways. In conclusion, our results showed that the effect and mechanism of Sini Powder and Tong xie yao fang decoction in IBS treatment were in multi-ingredient, multitargets and multipathways, which would provide several potential and promising strategies for the further research and development of Sini Powder and Tong xie yao fang decoction on IBS treatment.

The Colonic Mucosal MicroRNAs, MicroRNA-219a-5p, and MicroRNA-338-3p Are Downregulated in Irritable Bowel Syndrome and Are Associated With Barrier Function and MAPK Signaling

Alterations in microRNA (miRNA) and in the intestinal barrier are putative risk factors for irritable bowel syndrome (IBS). We aimed to identify differentially expressed colonic mucosal miRNAs, their targets in IBS compared to healthy controls (HCs), and putative downstream pathways. Twenty-nine IBS patients (15 IBS with constipation [IBS-C], 14 IBS with diarrhea [IBS-D]), and 15 age-matched HCs underwent sigmoidoscopy with biopsies. A nCounter array was used to assess biopsy specimen-associated miRNA levels. A false discovery rate (FDR) < 10% was considered significant. Real-time polymerase chain reaction (PCR) was used to validate differentially expressed genes. To assess barrier function, trans-epithelial electrical resistance (TEER) and dextran flux assays were performed on Caco-2 intestinal epithelial cells that were transfected with miRNA-inhibitors or control inhibitors. Protein expression of barrier function associated genes was confirmed using western blots. Four out of 247 miRNAs tested were differentially expressed in IBS compared to HCs (FDR < 10%). Real-time PCR validation suggested decreased levels of miR-219a-5p and miR-338-3p in IBS (P = .026 and P = .004), and IBS-C (P = .02 and P = .06) vs. HCs as the strongest associations. Inhibition of miR-219a-5p resulted in altered expression of proteasome/barrierfunction genes. Functionally, miR-219a-5p inhibition enhanced the permeability of intestinal epithelial cells as TEER was reduced (25-50%, P < .05) and dextran flux wasincreased (P < .01). Additionally, inhibition of miR-338-3p incells caused alterations in the mitogen-activated protein kinase (MAPK) signaling pathway genes. TwomicroRNAs that potentially affect permeability and visceral nociception were identified to be altered in IBS patients. MiR-219a-5p and miR-338-3p potentially alter barrier function and visceral hypersensitivity via neuronal and MAPK signaling and could be therapeutic targets in IBS.

Pharmacological Therapies and Their Clinical Targets in Irritable Bowel Syndrome With Diarrhea

Irritable bowel syndrome (IBS) is one of the most common disorders of the gut-brain axis, which affects approximately 4% of the global population. The Rome IV criteria define IBS as chronic or recurrent abdominal pain associated with altered bowel habits. Patients can be categorized in four subtypes: IBS with predominant constipation (IBS-C), predominant diarrhea (IBS-D), mixed bowel habits (IBS-M), and unclassified (IBS-U). IBS is associated with a lower quality of life, reduced work productivity, and high healthcare costs. When comparing subtypes, patients with IBS-D report lower disease related quality of life. Due to the scope of this review, we have solely focused on patients with IBS-D. Choosing the right pharmacological treatment in these patients remains challenging due to the heterogeneous patient population, patients’ expectation of the treatment outcome, unavailability of efficacious drugs, and the multifactorial and incompletely understood underlying pathophysiology. Currently, pharmacological treatment options target individual symptoms, such as abdominal pain, altered bowel habits, and bloating. In this review, we aimed to summarize the current and recent pharmacological treatment options in IBS-D, targeting the predominant gastrointestinal symptoms. Additionally, we proposed a pharmacological treatment algorithm which healthcare professionals could use when treating individual patients with IBS-D.

Potential neuro-immune therapeutic targets in irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder characterized by recurring abdominal pain and disturbed bowel habits. The aetiology of IBS is unknown but there is evidence that genetic, environmental and immunological factors together contribute to the development of the disease. Current treatment of IBS includes lifestyle and dietary interventions, laxatives or antimotility drugs, probiotics, antispasmodics and antidepressant medication. The gut–brain axis comprises the central nervous system, the hypothalamic pituitary axis, the autonomic nervous system and the enteric nervous system. Within the intestinal mucosa there are close connections between immune cells and nerve fibres of the enteric nervous system, and signalling between, for example, mast cells and nerves has shown to be of great importance during GI disorders such as IBS. Communication between the gut and the brain is most importantly routed via the vagus nerve, where signals are transmitted by neuropeptides. It is evident that IBS is a disease of a gut–brain axis dysregulation, involving altered signalling between immune cells and neurotransmitters. In this review, we analyse the most novel and distinct neuro-immune interactions within the IBS mucosa in association with already existing and potential therapeutic targets.

Review article: transient receptor potential channels as possible therapeutic targets in irritable bowel syndrome.

Abdominal pain in irritable bowel syndrome (IBS) remains challenging to treat effectively. Researchers have attempted to elucidate visceral nociceptive processes in order to guide treatment development. Transient receptor potential (TRP) channels have been implied in the generation (TRPV1, TRPV4, TRPA1) and inhibition (TRPM8) of visceral pain signals. Pathological changes in their functioning have been demonstrated in inflammatory conditions, and appear to be present in IBS as well. To provide a comprehensive review of the current literature on TRP channels involved in visceral nociception. In particular, we emphasise the clinical implications of these nociceptors in the treatment of IBS. Evidence to support this review was obtained from an electronic database search via PubMed using the search terms "visceral nociception," "visceral hypersensitivity," "irritable bowel syndrome" and "transient receptor potential channels." After screening the abstracts the articles deemed relevant were cross-referenced for additional manuscripts. Recent studies have resulted in significant advances in our understanding of TRP channel mediated visceral nociception. The diversity of TRP channel sensitization pathways is increasingly recognised. Endogenous TRP agonists, including poly-unsaturated fatty acid metabolites and hydrogen sulphide, have been implied in augmented visceral pain generation in IBS. New potential targets for treatment development have been identified (TRPA1 and TRPV4,) and alternative means of affecting TRP channel signalling (partial antagonists, downstream targeting and RNA-based therapy) are currently being explored. The improved understanding of mechanisms involved in visceral nociception provides a solid basis for the development of new treatment strategies for abdominal pain in IBS.

Mesalazine Has No Effect on Mucosal Immune Biomarkers in Patients with Diarrhea-Dominant Irritable Bowel Syndrome Referred to Shariati Hospital: A Randomized Double-Blind, Placebo-Controlled Trial.

BACKGROUND Intestinal mast cells may cause gastrointestinal symptoms in patients with diarrhea-dominant irritable bowel syndrome (IBS). The objective of this study was to determine the effect of mesalazine on the number of lamina propria mast cells and clinical manifestations of patients with diarrhea-dominant IBS referred to Shariati Hospital affiliated to Tehran University of Medical Sciences. METHODS This was a randomized placebo-controlled double-blind trial conducted on 49 patients with diarrhea-dominant IBS. The patients were randomly assigned to one of the experiment or control groups. The patients in experiment group took 2400 mg mesalazine daily in three divided doses for 8 weeks and the patient in control group took placebo on the same basis. Our first targeted outcome was an assigned downturn of mast cells number to the safe colonic baseline and the next one was a marked palliation of disease symptoms. Data were analyzed conforming intention-to-treat method. We used MANCOVA test to compare our both assigned outcomes in the two groups. We also compared the data with baseline values in both groups.All statistical tests were performed at the significance level of 0.05. RESULTS There was no significant difference between Mesalazine and placebo groups regarding the number of mast cells (p value=0.396), abdominal pain (p value=0.054), bloating (p value=0.365), defecation urgency (p value=0.212), and defecation frequency (p value=0.702). CONCLUSION Mesalazine had no significant effect either on the number of mast cells or on the severity of disease symptoms. This finding seems to be inconsistent with the hypothesis indicating immune mechanisms as potential therapeutic targets in IBS. The possible difference in this effect of Mesalazine should be evaluated in further studies among populations varying in race, ethnic, and geographical characteristics.

The influence of interoceptive awareness on functional connectivity in patients with irritable bowel syndrome.

Irritable bowel syndrome (IBS) is characterized by visceral hypersensitivity likely related to altered processing of sensory stimuli along the brain-gut axis. Previous neuroimaging studies demonstrated structural and functional alteration of several brain areas involved in bodily representation, e.g. the insula, in patients with IBS. By means of resting-state functional magnetic resonance imaging (rs-fMRI) we searched for alteration of functional connectivity within the network involved in self-bodily consciousness. We found significant inverse correlation between hypochondriasis assessed through a clinical questionnaire and connectivity between posterior cingulate cortex and left supramarginal gyrus, extending into the adjacent superior temporal gyrus. Moreover, we observed a significant and positive correlation between a clinical questionnaire assessing interoception and connectivity between left anterior ventral insula and two clusters located in supramarginal gyrus bilaterally.Our findings highlight an "abnormal network synchrony" reflecting functional alteration, in the absence of structural and micro-structural changes, which might represent a possible therapeutic target for Irritable Bowel Syndrome.

The relationship between irritable bowel syndrome and psychiatric disorders: from molecular changes to clinical manifestations.

Irritable bowel syndrome (IBS) is a functional syndrome characterized by chronic abdominal pain accompanied by altered bowel habits. Although generally considered a functional disorder, there is now substantial evidence that IBS is associated with a poor quality of life and significant negative impact on work and social domains. Neuroimaging studies documented changes in the prefrontal cortex, ventro-lateral and posterior parietal cortex and thalami, and implicate alteration of brain circuits involved in attention, emotion and pain modulation. Emerging data reveals the interaction between psychiatric disorders including generalized anxiety disorder, panic disorder, major depressive disorder, bipolar disorder, and schizophrenia and IBS, which suggests that this association should not be ignored when developing strategies for screening and treatment. Psychological, social and genetic factors appear to be important in the development of IBS symptomatology through several mechanisms: alteration of HPA axis modulation, enhanced perception of visceral stimuli or psychological vulnerability. Elucidating the molecular mechanisms of IBS with or without psychiatric comorbidities is crucial for elucidating the pathophysiology and for the identification of new therapeutical targets in IBS.

Review article: evidence for the role of gut microbiota in irritable bowel syndrome and its potential influence on therapeutic targets

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease with a substantial social and economic burden. Treatment options remain limited and research on the aetiology and pathophysiology of this multifactorial disease is ongoing. To discuss the potential role of gut microbiota in the pathophysiology of IBS and to identify possible interactions with pathophysiologic targets in IBS. Articles were identified via a PubMed database search ['irritable bowel syndrome' AND (anti-bacterial OR antibiotic OR flora OR microbiota OR microflora OR probiotic)]. English-language articles were screened for relevance. Full review of publications for the relevant studies was conducted, including additional publications that were identified from individual article reference lists. The role of gut microbiota in IBS is supported by varying lines of evidence from animal and human studies. For example, post-infectious IBS in humans is well documented. In addition, certain probiotics and nonsystemic antibiotics appear to be efficacious in the treatment of IBS. Mechanisms involved in improving IBS symptoms likely go beyond mere changes in the composition of the gut microbiota, and accumulating animal data support the interplay of microbiota with other IBS targets, such as the gut-brain axis, visceral hypersensitivity, mucosal inflammation and motility. The role of the gut microbiota is still being elucidated; however, it appears to be one of several important factors that contributes to the aetiology and pathophysiology of the irritable bowel syndrome.

Psychological Stress Induces Visceral Analgesic or Hyperalgesic Response in Rodents: A Role of Preconditions.

A dual action of stress on pain modulation has been well characterized in the somatic pain studies, while much less is known in the visceral field. In the context of clinical observations that stress plays a critical role in the pathophysiology, symptoms presentation and clinical outcome of functional gastrointestinal disorders such as irritable bowel syndrome (IBS), a number of acute and chronic stress models have been developed in rodents. Recent data have demonstrated that the state of the animal tested (naïve vs. exposed to surgery), its social environment (group housing vs. single housing), the methods used to record visceromotor responses (EMG requiring surgery and antibiotic after surgery vs. manometry not requiring surgery/antibiotic) can significantly affect the analgesic response to exteroceptive stressors. Growing body of evidence indicates that a new noninvasive solid-state manometric method to monitor viscero motor response is valuable to unravel both analgesia and hyperalgesia without confounding factors. This is of critical importance regarding the recently recognized role of a compromised engagement of the inhibitory descending pain pathways in IBS patients. Better understanding of mechanisms of stress-related modulation of visceral pain leading to analgesia and hyperalgesia, along with the role of sex-dependent factors and complex interactions of the brain-gut-enteric microbiota axis may lead to new therapeutic targets in IBS.

Effect of mesalazine on mucosal immune biomarkers in irritable bowel syndrome: a randomized controlled proof‐of‐concept study

Intestinal immune infiltration contributes to symptoms in patients with irritable bowel syndrome (IBS). To assesses the effect of mesalazine (mesalamine) on mucosal immune cells in patients with IBS, through a pilot study. A randomized, double-blind, placebo-controlled trial in 20 patients with IBS in tertiary care setting. Patients were randomized to receive placebo or 800 mg mesalazine three times daily for 8 weeks. The primary endpoint was a significant reduction in total colonic immune cells on biopsies obtained at the end of treatment compared to baseline. Secondary endpoints included effects on subsets of immune cells, inflammatory mediators and symptom severity. Intention-to-treat analysis was performed. Mesalazine markedly reduced immune cells as compared with placebo (P = 0.0082); this effect was ascribed to a marked inhibition of mast cells (P = 0.0014). Mesalazine significantly increased general well-being (P = 0.038), but had no significant effects on abdominal pain (P = 0.084), bloating (P = 0.177) or bowel habits. No serious drug-related adverse events were reported during the study. Mesalazine is an effective and safe approach to reduce mast cell infiltration and may improve general well-being in patients with IBS. These results support the hypothesis that immune mechanisms represent potential therapeutic targets in IBS.

Impaired intestinal barrier integrity in the colon of patients with irritable bowel syndrome: involvement of soluble mediators

Background:Growing evidence suggests that patients with irritable bowel syndrome (IBS) have increased intestinal permeability. In addition, mucosal soluble mediators are involved in the pathophysiology of pain in IBS. We aimed...

CRF1 Receptors as a Therapeutic Target for Irritable Bowel Syndrome

The characterization of the corticotropin-releasing factor (CRF) family of neuroendocrine regulatory peptides, the cloning and pharmacological characterization of two CRF receptor subtypes (CRF(1) and CRF(2)), and the development of selective CRF receptor antagonists provided new insight to unravel the mechanisms of stress and the potential involvement of the CRF system in different pathophysiological conditions, including functional gastrointestinal disorders, mainly irritable bowel syndrome (IBS), and psychopathologies such as anxiety/depression. Compelling pre-clinical data showed that brain CRF administration mimics acute stress-induced colonic responses and enhances colorectal distension-induced visceral pain in rats through CRF(1) receptors. Similarly, peripheral CRF reduced the pain threshold to colonic distension and increased colonic motility in humans and rodents. These observations mimic the manifestations of IBS, characterized by abdominal bloating/discomfort and altered bowel habits. Moreover, CRF-CRF(1) pathways have been implicated in the development of anxiety/depression. These psychopathologies, together with stressful life events, have high comorbidity with IBS, and are considered significant components of the disease. From these observations, CRF(1) receptors have been suggested as a target to treat IBS. Peripherally acting CRF(1) antagonists might directly improve IBS symptoms, as related to motility, secretion and immune response. On the other hand, central actions will be beneficial as to prevent the psychopathologies that co-exist with IBS and as a way to modulate the central processing of stress- and visceral pain-related signals. Here, we review the pre-clinical and clinical data supporting these assumptions, and address the efforts done at a pharmaceutical level to develop effective therapies targeting CRF(1) receptors for functional gastrointestinal disorders.

Current targets in irritable bowel syndrome: an interview with Eamonn Quigley

Eamonn M M Quigley, MD, FACG, is Vice-President of the World Gastroenterology Organisation and Secretary of the American College of Gastroenterology. He is also Professor of Medicine and Human Physiology and Head of the Medical School at the National University of Ireland in Cork. Between 1991 and 1998, he served as Chief of Gastroenterology and Hepatology at the University of Nebraska Medical Center, where he was also Professor in the Department of Internal Medicine. Dr Quigley has been awarded a Fogarty International Fellowship by the National Institutes of Health and an Ainsworth Traveling Scholarship from University College Cork. He completed higher medical training in gastroenterology and internal medicine as a Senior Registrar and Lecturer in the Department of Medicine at Hope Hospital and the University of Manchester. His MD thesis was awarded by the National University of Ireland in 1984 and he received his medical education at University College Cork, graduating MB BCh BAO in 1976. Dr Quigley served as Editor-in-Chief of the American Journal of Gastroenterology from 1997 to 2003, and he has published > 400 articles, including original manuscripts, editorials, review articles, book chapters and case reports. He is also interested and involved in education in the area of gastroenterology and has participated in, or directed symposia, workshops and other teaching forums and prepared a variety of related teaching aids.

Protease-activated receptors: potential therapeutic targets in irritable bowel syndrome?

Protease-activated receptors (PARs) are a family of four G-protein-coupled receptors (PAR-1 to PAR-4) activated by the proteolytic cleavage of their N-terminal extracellular domain. This activation first involves the recognition of the extracellular domain by proteases, such as thrombin, but also trypsin or tryptase which are particularly abundant in the gastrointestinal tract, both under physiological circumstances and in several digestive diseases. Activation of PARs, particularly of PAR-1 and -2, modulates intestinal functions, such as gastrointestinal motility, visceral nociception, mucosal inflammatory response, and epithelial functions (intestinal secretion and permeability). As these physiological properties have been shown to be altered in various extents and combinations in different clinical presentations of irritable bowel syndrome, PARs appear as putative targets for future therapeutic intervention in these patients.