The multi-herbal drug STW 5 (Iberogast) has prosecretory action in the human intestine

Pharmacologic treatment of irritable bowel syndrome. Position statement of the Asociación Mexicana de Gastroenterología, 2024

INTRODUCTION

The aim of this position statement is to provide health professionals with an updated and evidence-based guideline for the pharmacologic management of irritable bowel syndrome (IBS) in Mexico.

MATERIAL AND METHODS

A literature review was conducted that included relevant guidelines and studies, up to the date of its publication. The mechanism of action, specific indications in IBS, safety profile, and availability of each therapeutic class were evaluated. The recommendations were developed by 14 experts, considering the clinical reality of IBS patients in Mexico.

RESULTS

Specific recommendations were issued for each class. Antispasmodics (alone or combined) are used as first-line therapy for pain management, whereas antidiarrheals, such as loperamide, are used for reducing diarrhea in diarrhea-predominant IBS (IBS-D) and laxatives are used for constipation in constipation-predominant IBS (IBS-C). 5-HT4 agonists (prucalopride and mosapride) are recommended in IBS-C and 5-HT3 antagonists (ondansetron) are recommended in IBS-D. Linaclotide is the only secretagogue available in Mexico and is used in IBS-C. Rifaximin-alpha stands out for its efficacy in a subgroup of patients with IBS-D or mixed IBS. Probiotics are conditionally recommended as adjuvant therapy due to heterogeneous evidence. Neuromodulators (tricyclic antidepressants, selective serotonin reuptake inhibitors, etc.) are recommended as second-line treatment for pain management. Mesalazine can be used in IBS-D, but the corresponding evidence is weak.

CONCLUSION

Overall, these recommendations provide a solid framework for personalizing treatment, based on the clinical characteristics of the Mexican patient with IBS.

A Review of the Mechanisms of Action of the Herbal Medicine, STW 5-II, Underlying Its Efficacy in Disorders of Gut-Brain Interaction

BACKGROUND

Functional dyspepsia (FD) and irritable bowel syndrome (IBS) are disorders of gut-brain interaction (DGBIs). Patients with these disorders experience abdominal symptoms, frequently in relation to meal intake, and often are treated using pharmacological approaches that offer limited symptom relief. In addition to various pharmacotherapies, established treatment options include lifestyle modifications (such as diet) and, in certain patients, psychological interventions. Because of the limitations of the currently available treatments, many patients look for alternative options, including herbal preparations.

PURPOSE

In this review, we summarize the preclinical and clinical evidence informing the use of the herbal preparation, STW 5-II, for the treatment of patients with FD and IBS. Data from clinical trials provide evidence that STW 5-II is superior to placebo in offering symptom relief. Moreover, a substantial body of preclinical data on the mechanisms of action of STW 5-II suggests that its ingredients target multiple mechanisms relevant to pathophysiology and symptom generation that may underlie its beneficial clinical effects in patients with DGBIs.

Functional gastrointestinal disorders in children: Effectivity, safety, and tolerability of the herbal preparation STW-5 (Iberogast®) in general practice

BACKGROUND

Functional gastrointestinal disorders (FGIDs) of the upper and lower digestive system in children and adolescents present with heterogeneous gastrointestinal symptoms and are a common reason for specialist consultations. The herbal medicinal preparation STW-5 has already shown efficacy and safety in clinical studies with more than 7000 adult participants suffering from functional dyspepsia (FD) or irritable bowel syndrome (IBS). Here, we evaluate with a prospective observational study the effectivity and safety of STW-5 in children with FGID under real-life conditions and interpret these data versus the background of controlled clinical studies in a predominantly adult population.

METHODS

This prospective observational study included 980 children (age 3-14 years) with FGID. For inclusion, Rome III criteria were recommended to apply. The inclusion of the patients for treatment with STW-5 followed routine clinical practice. Patients were treated for approximately 1 week. The presence and severity of symptoms was documented at the study start and at the end of treatment period utilizing the adapted gastrointestinal symptom score (GIS). Other target parameters included global effectivity and tolerability assessments as well as adverse events.

RESULTS

The average patient age was 7.6 ± 2.9 years. Most of the patients were treated for IBS (n = 418; 43 %) or FD (n = 259; 26 %), with a mean baseline GIS of 16.1 ± 8.9. During the treatment period, the GIS decreased 76 % to 3.8 ± 4.2. The decrease in symptoms was similar for different age groups, gender, and indications. Patients with a shorter duration of complaints had a lower GIS at study end (p < 0.0001. The global treatment effect was assessed as good or very good by 87-89 % of patients/parents and physicians. Physicians rated the global tolerability as good or very good for 95 % of the patients. Seven patients (0.7 %) reported adverse events.

CONCLUSIONS

The treatment effect of STW-5 in this study was in its range comparable to according data from controlled clinical trials with predominantly adult participants.Thus, supporting robustness of these data generated in an uncontrolled observational setting. The results of this observational study indicate that STW-5 may be an effective and well tolerated treatment option also for children with FGIDs.

STW 5 Herbal Preparation Modulates Wnt3a and Claudin 1 Gene Expression in Zebrafish IBS-like Model

AIM

Irritable bowel syndrome (IBS) is a functional bowel disorder characterized by chronic abdominal pain and stool irregularities. STW 5 has proven clinical efficacy in functional gastrointestinal disorders, including IBS, targeting pathways that suppress inflammation and protect the mucosa. Wnt signaling is known to modulate NF-kβ-dependent inflammatory cytokine production. This sparked the idea of evaluating the impact of STW 5 on the expression of inflammatory-response and Wnt/β catenin-target genes in an IBS-like model.

MAIN METHODS

We used zebrafish and dextran sodium sulfate (DSS) treatment to model IBS-like conditions in vivo and in vitro and examined the effects of subsequent STW 5 treatment on the intestines of DSS-treated fish and primary cultured intestinal and neuronal cells. Gross gut anatomy, histology, and the expression of Wnt-signaling and cytokine genes were analyzed in treated animals and/or cells, and in controls.

KEY FINDINGS

DSS treatment up-regulated the expression of interleukin-8, tumor necrosis factor-α, wnt3a, and claudin-1 in explanted zebrafish gut. Subsequent STW 5 treatment abolished both the macroscopic signs of gut inflammation, DSS-induced mucosecretory phenotype, and normalized the DSS-induced upregulated expression of il10 and Wnt signaling genes, such as wnt3a and cldn1 in explanted zebrafish gut. Under inflammatory conditions, STW 5 downregulated the expression of the pro-inflammatory cytokine genes il1β, il6, il8, and tnfα while it upregulated the expression of the anti-inflammatory genes il10 and wnt3a in enteric neuronal cells in vitro.

SIGNIFICANCE

Wnt signaling could be a novel target for the anti-inflammatory and intestinal permeability-restoring effects of STW 5, possibly explaining its clinical efficacy in IBS.

Herbal medicines in functional dyspepsia-Untapped opportunities not without risks

BACKGROUND

Contemporary treatments for functional dyspepsia have limitations. Herbal medicine has been suggested as adjunctive treatment. With growing scientific recognition and public interests, an in-depth review of this is timely.

AIMS/PURPOSE

To evaluate the therapeutic potential and problems that may be associated with the adoption of herbal medicines in functional dyspepsia.

METHODS

We reviewed the treatment landscape of functional dyspepsia and assessed the scientific community's interest in herbal medicine. Preclinical pharmacological and clinical trial data were reviewed for several herbal medicines available in the market. Challenges associated with adoption of herbal medicine in mainstream medicine were critically evaluated.

RESULTS

We found that herbal medicines frequently comprise a combination of herbs with multiple reported pharmacological effects on gastrointestinal motility and secretory functions, as well as cytoprotective and psychotropic properties. We identified a number of commercially available herbal products that have undergone rigorous clinical trials, involving large numbers of well-defined subjects, reporting both efficacy and safety for functional dyspepsia. Persisting concerns include lack of rigorous assessments for majority of products, toxicity, consistency of ingredients, dose standardizations, and quality control. We provide a quality framework for its evaluation.

CONCLUSIONS

We commend herbal medicine as a viable future option in managing functional dyspepsia. An attractive appeal of herbal medicine is the prospect to simultaneously target multiple pathophysiological mechanisms. Wider adoption and acceptance of herbal medicines in treatment algorithms of functional dyspepsia will require the application of the scientific rigor expected of chemical therapies, to all stages of their development and evaluation.

Effects of the herbal preparation STW 5-II on in vitro muscle activity in the guinea pig stomach

BACKGROUND

STW 5 is a combination of nine medicinal herbal extracts and used to treat functional gastrointestinal disorders including functional dyspepsia. It has a region-specific effect by relaxing the proximal and contracting the distal stomach. The research combination STW 5-II (Iberogast^® Advance) lacks three herbal extracts but seems clinically as effective as STW 5. However, the action of STW 5-II on gastric motility is unknown.

METHODS

In vitro circular and longitudinal muscle tone and contractility were recorded from guinea pig gastric fundus and antrum with isometric force transducers.

KEY RESULTS

STW 5-II decreased concentration-dependently (64-512 µg/ml) the tone of circular and longitudinal muscle strips from the fundus. In contrast, STW 5-II increased concentration-dependently contraction amplitude in antral circular and longitudinal muscle. The effects were region-dependent but comparable in the two muscle layers. Application of 512 µg STW 5 or STW 5-II revealed comparable effects in the fundus and antrum circular and longitudinal muscle strips.

CONCLUSIONS AND INTERFERENCES

STW 5-II had a region-specific effect and relaxed the proximal stomach but increased the contractility in the antrum. It was as effective as STW 5 which may explain its comparable clinical effects in treating functional dyspepsia. Impaired accommodation may be normalized through relaxation of the fundus, while the motility-promoting effects leading to an increase in antral motility may activate the gastric pump.

Treating Chronic Abdominal Pain in Patients with Chronic Abdominal Pain and/or Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is probably the most common diagnosis in gastroenterology involving the brain-gut axis. By definition, pain is the most frequent symptom experienced by patients. It is important to understand the biopsychosocial and physiologic aspects of the disease when discussing treatment of IBS. Such therapies as lifestyle modifications, changes in diet, and cognitive behavioral therapy should be used in conjunction with pharmacotherapy rather than pharmacotherapy alone. The pathophysiologic mechanisms are reviewed in this article along with the current treatments available, in the era of growing demand for more effective treatments for the pain component of IBS.

STW5 (Iberogast®) for constipation in Parkinson's disease

BACKGROUND

Chronic constipation is one of the most frequent non-motor symptoms in Parkinson's disease (PD), and impairs patients' quality of life.

OBJECTIVE

The aim of this pilot study was to assess the efficacy and the tolerability of STW5, a phytotherapeutic agent composed of nine plant extracts, for the treatment of constipation in patients with PD.

METHODS

We carried out an open monocentric study of STW5 in the treatment of constipation in parkinsonian patients. Forty-four PD patients with a mean age of 66.4±7.3 years (range, 35-78), a mean disease duration of 12.6±5.4 years (range, 3-27) and with constipation defined by Rome III criteria for functional constipation were included. Following a two-week laxative-free baseline period, all the patients were treated with 20 drops STW5 t.i.d for 28 days, after a seven-day titration period. Treatment efficacy was defined as marked improvement of stool frequency with an increase of three exonerations during the last week of treatment when compared to the week before the initiation of treatment. Responder rate for stool frequency was estimated at 29/45 patients.

RESULTS

An increase of stool frequency≥three eliminations/week was observed in only four out of 44 patients (9.0%) at the end of the study. The only significant difference observed before and after treatment was a decrease in stool consistency (P=0.0272).

CONCLUSIONS

Our results suggest that STW5 has a safety profile but is not effective as a phytotherapeutic agent in constipation related to Parkinson's disease.

Application of an in vitro digestion model to study the metabolic profile changes of an herbal extract combination by UHPLC-HRMS

BACKGROUND

STW 5 is a fixed herbal combination containing extracts from nine medicinal plants: bitter candytuft, greater celandine, garden angelica roots, lemon balm leaves, peppermint leaves, caraway fruits, licorice roots, chamomile flowers, and milk thistle fruit. STW 5 is a clinically proven treatment for functional dyspepsia and irritable bowel syndrome.

PURPOSE

Using a static in vitro method, we simulated oral, gastric, and small intestinal digestion and analyzed the metabolic profile changes by UHPLC-HRMS to determine the impact of oro-gastro-intestinal digestion on STW 5 constituents.

STUDY DESIGN AND METHODS

STW 5 was incubated according to the InfoGest consensus method. Samples of each digestive phase were analyzed by UHPLC-HRMS in ESI positive and negative modes. After data processing, background subtraction, and normalization, the peak areas of detectable compounds were compared to untreated reference samples and recovery ratios were calculated to monitor the metabolic profile of STW 5 during simulated digestion.

RESULTS

Although the levels of some constituents were reduced, we did not observe complete degradation of any of the constituents of STW 5 upon in vitro digestion. We did not detect any new metabolites beyond increased levels of caffeic acid and liquiritigenin due to degradation of progenitor compounds. Changes observed in intestinal bioaccessibility ratios were mainly a result of isomerization, hydrolysis, protein binding, and low water solubility.

CONCLUSION

The majority of STW 5 constituents are stable towards simulated in vitro digestion and can reach the colon to interact with gut microbiota if they remain unabsorbed in the upper intestinal tract.

Pharmacological and non-pharmacological treatments for irritable bowel syndrome: Protocol for a systematic review and network meta-analysis

BACKGROUND

The global prevalence of Irritable bowel syndrome (IBS) is estimated to be as high as 15% and a number of different non-pharmacological and pharmacological treatments have been used to manage IBS in clinical practice, which poses great challenges for clinicians to make appropriate decisions. Hence, a systematic review and network meta-analysis on all available pharmacological and non-pharmacological treatments for IBS is needed to provide reliable evidence.

METHODS

We will search the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane IBD Group Specialized Trials Register, MEDLINE, EMBASE, and Chinese Biomedical medicine (CBM) from inception to 31, May 2019. Randomized controlled trials of pharmacological and nonpharmacological interventions for IBS will be included. Study quality will be assessed on the basis of the methodology and categories described in the Cochrane Collaboration Handbook. Primary outcomes are global or clinical improvement and quality of life. A Bayesian network meta-analysis would be performed, and relative ranking of agents would be assessed. A node splitting method will be used to examine the inconsistency between direct and indirect comparisons when a loop connecting 3 arms exists.

RESULTS

Researchers will rank the effectiveness and safety of the potentials interventions for IBS according the characteristics of patients by conducting an advanced network meta-analysis based on Bayesian statistical model, and interpret the results by using GRADE approach.

CONCLUSION

The conclusion of our study will provide updated evidence to rank the effectiveness and safety of pharmacological and non-pharmacological interventions for IBS.

ETHICS AND DISSEMINATION

Ethical approval is not applicable since this study is a network meta-analysis based on published trials.

PROTOCOL REGISTRATION NUMBER

CRD42018083844.

Management Options for Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is associated with diverse pathophysiologic mechanisms. These mechanisms include increased abnormal colonic motility or transit, intestinal or colorectal sensation, increased colonic bile acid concentration, and superficial colonic mucosal inflammation, as well as epithelial barrier dysfunction, neurohormonal up-regulation, and activation of secretory processes in the epithelial layer. Novel approaches to treatment include lifestyle modification, changes in diet, probiotics, and pharmacotherapy directed to the motility, sensation, and intraluminal milieu of patients with IBS. Despite recent advances, there is a need for development of new treatments to relieve pain in IBS without deleterious central or other adverse effects.

New treatments and therapeutic targets for IBS and other functional bowel disorders

Functional bowel disorders (FBDs) are a spectrum of disorders characterized by combinations of symptoms attributable to the lower gastrointestinal tract. Most current first-line therapies for IBS and other FBDs target the predominant symptom and mainly affect one symptom in the symptom complex. Additional broadly effective treatment alternatives targeting the entire symptom complex are needed. New drugs for FBDs (such as lubiprostone, linaclotide, plecanatide, prucalopride, eluxadoline and rifaximin) target key mechanisms in the pathophysiology of these disorders and improve both the abnormal bowel habit and other key symptoms, such as abdominal pain and bloating. The current development of new treatment alternatives is focusing on different aspects of the complex pathophysiology of IBS and other FBDs: gut microenvironment (via diet and modulation of gut microbiota), enterohepatic circulation of bile acids, gastrointestinal secretion, motility and sensation, gut-brain interactions, gut barrier function and the immune system within the gastrointestinal tract. Studies also suggest that personalized treatment of IBS and other FBDs is possible using various diagnostic markers.

bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM)-the active metabolite of the laxatives bisacodyl and sodium picosulfate-enhances contractility and secretion in human intestine in vitro

BACKGROUND

Stimulant laxatives are widely used to treat constipation. We investigated in human small and large intestinal preparations the effects of bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM), the active metabolite of the laxatives bisacodyl and sodium picosulfate on smooth muscle tone and epithelial secretion.

METHODS

Circular and longitudinal muscle tone of small or large intestinal preparations were recorded with isometric force transducers. Epithelial ion flux (I_SC ) and tissue resistance was measured with Ussing chamber technique after apical and basolateral BHPM application to large intestinal mucosa/submucosa preparations. Studies were performed in macroscopically normal specimens from 79 patients.

KEY RESULTS

BHPM concentration-dependently (0.5-5 μM) increased the tone of circular and longitudinal muscle from small to large intestine. The effect was strongest in large intestinal longitudinal muscle and smallest in small intestinal circular muscle. Increase in muscle tone was prevented by the L-type Ca⁺⁺ channel blocker nifedipine but insensitive to the nerve blocker tetrodotoxin. Apical or basolateral BHPM concentration-dependently decreased or increased I_SC, respectively. The K_Ca 1.1 (BK) channel blocker iberiotoxin reversed apical I_SC decrease whereas tetrodotoxin reversed basolateral I_SC increase. BHPM had no effect on tissue resistance or nerve-mediated secretory or muscle response with one exception: at the highest concentration basolateral BHPM reduced nerve-mediated secretion.

CONCLUSIONS AND INTERFERENCES

BHPM enhanced mucosal secretion and muscle contractility. Results suggested that the laxative effect of BHPM was a consequence of the increase in muscle tone as well as an increased K⁺ secretion when acting luminally and a nerve-driven Cl^- and HCO₃^- secretion once acting basolaterally after absorption.

Mechanism of Action of STW 5 in Functional Dyspepsia and IBS: The Origin of Multi-Target

BACKGROUND

STW 5 is a complex herbal combination preparation composed of 9 different herbal extracts. As an herbal medicinal product, this preparation is indicated for treating functional dyspepsia (FD) and irritable bowel syndrome (IBS). Its efficacy and practical applicability was demonstrated in several clinical studies.

SUMMARY

Each herbal constituent of STW 5 has distinct effects on the gastrointestinal tract, and each shows activity through different mechanisms of action: among others, the single extracts have effects on nerves, smooth muscles, epithelial, and inflammatory cells. For example, they have relaxing or tonicizing effects on gastrointestinal muscles, and they counteract inflammation through different physiological systems, contributing to the clinical efficacy through modulation of multiple therapeutic targets. Key Messages: STW 5 is a role model for the concept of multi-targeting in therapy. Especially in complex syndromes such as FD and IBS, simultaneous multi-targeting of different functional causes seems to be a more promising approach than the classical paradigm of one disease - one receptor - one effect.

Probiotics, fibre and herbal medicinal products for functional and inflammatory bowel disorders

Functional bowel disorders (FBD), mainly irritable bowel syndrome (IBS) and functional constipation (FC, also called chronic idiopathic constipation), are very common worldwide. Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, although less common, has a strong impact on patients' quality of life, as well as being highly expensive for our healthcare. A definite cure for those disorders is still yet to come. Over the years, several therapeutic approaches complementary or alternative to traditional pharmacological treatments, including probiotics, prebiotics, synbiotics, fibre and herbal medicinal products, have been investigated for the management of both groups of diseases. However, most available studies are biased by several drawbacks, including small samples and poor methodological quality. Probiotics, in particular Saccharomyces boulardii and Lactobacilli (among which Lactobacillus rhamnosus), synbiotics, psyllium, and some herbal medicinal products, primarily peppermint oil, seem to be effective in ameliorating IBS symptoms. Synbiotics and fibre seem to be beneficial in FC patients. The probiotic combination VSL#3 may be effective in inducing remission in patients with mild-to-moderate ulcerative colitis, in whom Escherichia coli Nissle 1917 seems to be as effective as mesalamine in maintaining remission. No definite conclusions can be drawn as to the efficacy of fibre and herbal medicinal products in IBD patients due to the low number of studies and the lack of randomized controlled trials that replicate the results obtained in the individual studies conducted so far. Thus, further, well-designed studies are needed to address the real role of these therapeutic options in the management of both FBD and IBD.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

Neural influences on human intestinal epithelium in vitro

KEY POINTS

We present the first systematic and, up to now, most comprehensive evaluation of the basic features of epithelial functions, such as basal and nerve-evoked secretion, as well as tissue resistance, in over 2200 surgical specimens of human small and large intestine. We found no evidence for impaired nerve-evoked epithelial secretion or tissue resistance with age or disease pathologies (stomach, pancreas or colon cancer, polyps, diverticulitis, stoma reversal). This indicates the validity of future studies on epithelial secretion or resistance that are based on data from a variety of surgical specimens. ACh mainly mediated nerve-evoked and basal secretion in the small intestine, whereas vasoactive intestinal peptide and nitric oxide were the primary pro-secretory transmitters in the large intestine. The results of the present study revealed novel insights into regional differences in nerve-mediated secretion in the human intestine and comprise the basis by which to more specifically target impaired epithelial functions in the diseased gut.

ABSTRACT

Knowledge on basic features of epithelial functions in the human intestine is scarce. We used Ussing chamber techniques to record basal tissue resistance (R-basal) and short circuit currents (ISC; secretion) under basal conditions (ISC-basal) and after electrical field stimulation (ISC-EFS) of nerves in 2221 resectates from 435 patients. ISC-EFS was TTX-sensitive and of comparable magnitude in the small and large intestine. ISC-EFS or R-basal were not influenced by the patients' age, sex or disease pathologies (cancer, polyps, diverticulitis). Ion substitution, bumetanide or adenylate cyclase inhibition studies suggested that ISC-EFS depended on epithelial cAMP-driven chloride and bicarbonate secretion but not on amiloride-sensitive sodium absorption. Although atropine-sensitive cholinergic components prevailed for ISC-EFS of the duodenum, jejunum and ileum, PG97-269-sensitive [vasoactive intestinal peptide (VIP) receptor 1 antagonist] VIPergic together with L-NAME-sensitive nitrergic components dominated the ISC-EFS in colonic preparations. Differences in numbers of cholinergic or VIPergic neurons, sensitivity of epithelial muscarinic or VIP receptors, or stimulus frequency-dependent transmitter release were not responsible for the region-specific transmitter contribution to ISC-EFS. Instead, the low atropine-sensitivity of ISC-EFS in the colon was the result of high cholinesterase activity because neostigmine revealed cholinergic components. Colonic ISC-EFS remained unchanged after tachykinin, P2X, P2Y or A1 and A2 receptor blockade. R-basal was smaller and ISC-basal was higher in the small intestine. TTX and bumetanide decreased ISC-basal in all regions, suggesting nerve-dependent secretory tone. ISC-basal was atropine-sensitive in the small intestine and PG97-269-sensitive in the large intestine. This comprehensive study reveals novel insights into region-specific nerve-mediated secretion in the human small and large intestine.

Extracts from peppermint leaves, lemon balm leaves and in particular angelica roots mimic the pro-secretory action of the herbal preparation STW 5 in the human intestine

AIM

The herbal preparation STW 5 contains fresh plant extracts from bitter candytuft whole plant, extracts from greater celandine herb, angelica root, lemon balm leaves, peppermint leaves, caraway fruit, liquorice root, chamomile flower and milk thistle fruit. We recently reported that STW 5 increased intestinal chloride secretion and proposed that this action may be involved in its clinical efficacy in the treatment of irritable bowel syndrome. The aim of this study was to identify the extracts responsible for the secretory action in order to provide the basis to develop novel target oriented herbal combinations.

METHODS

We used the Ussing chamber voltage clamp technique to study the effects of individual extracts of STW 5 on short circuit current (Isc, reflecting electrogenic ion transport across epithelial cells) in mucosal/submucosal preparations of human small or large intestinal specimens and the human epithelial cell line T84.

RESULTS

STW 5 at concentrations of 512 µg/ml and 5120 µg/ml evoked an increase in Isc. The increase at the lower concentration was due to pro-secretory effects of angelica which were nerve mediated. The increase at the higher concentration was additionally mimicked by peppermint and lemon balm. The remaining extracts did not influence ISC in the large intestine. The results were similar in T84 cells except that angelica had no effect while chamomile induced secretion. These pro-secretory effects were reduced by adenylate cyclase inhibitor MDL-12330A, cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor CFTRinh-172 and calcium activated chloride channels blocker 4-acetamido-4-isothiocyanatostilbene-2,2-disulphonic acid (SITS). Liquorice decreased ISC only in small intestine which was reversed by the epithelial sodium channel blocker amiloride.

CONCLUSIONS

Results suggested that the pro-secretory action of STW 5 is mainly due to angelica with lesser contribution of peppermint and lemon balm. Their effects involve activation of cAMP- and Ca(++)-activated Cl(-) channels. We suggest that peppermint, lemon balm and in particular angelica may be the basis to develop novel herbal preparations to specifically treat secretory disorder based on impaired epithelial secretion, such as constipation.

The treatment of gastroparesis, constipation and small intestinal bacterial overgrowth syndrome in patients with Parkinson's disease

INTRODUCTION

Parkinson's disease (PD) affects the nerves of the entire gastrointestinal (GI) tract and may result in profound gastrointestinal (GI) dysfunction leading to poor patient outcomes. Common GI disturbances in patients with PD include gastroparesis (GP), constipation and small intestinal bacterial overgrowth syndrome (SIBO). In particular, GP is difficult to treat due to the limited options available and precautions, contraindications and adverse effects associated with the approved treatments. Moreover, some commonly used medications can worsen pre-existing PD.

AREAS COVERED

Our review will focus on treatment options for GP and SIBO with motilin agonists, dopamine receptor antagonists, Ghrelin agonists muscarinic agonists, 5-HT4 receptor agonists, antibiotics, probiotics and herbal formulation such as iberogast. Constipation occurs in the majority of patients with PD and fortunately many treatments are now available. Our review is based on original papers or reviews selected from PUBMED search and Cochrane reviews.

EXPERT OPINION

Motility disorders of the GI tract are found frequently in patients with PD and treating the underlying GI disorders caused by PD with various prokinetics and laxatives is paramount in achieving improvements in patient's motor function. Various prokinetics and laxatives are now available to provide some relief of the GI morbidity caused by PD leading even to better absorption of even the PD treatments.

Complementary and alternative medicine for gastroparesis

Complementary and alternative medicine is of great interest to patients with gastrointestinal disorders and some will choose to ask their health care providers about those therapies for which some scientific evidence exists. This review focuses on those therapies most commonly used by patients, namely acupuncture/electroacupuncture and various herbal formulations that have been the focus of clinical and laboratory investigation. A discussion of their possible mechanisms of action and the results of clinical studies are summarized.

Emerging drugs for functional dyspepsia

INTRODUCTION

Functional dyspepsia (FD) is a relatively common gastrointestinal clinical condition that remains poorly understood. Controversies remain regarding the definition, pathophysiology and optimum treatment. The current treatment of FD is limited and no established regimen is available.

AREAS COVERED

Recent advances have improved our understanding of the pathophysiology of the disease and have led to the development of newer tailored therapies. Novel agents such as the motilin receptor agonist camicinal and the muscarinic M1 and M2 receptor antagonist acotiamide appear promising; however, the need for a safe and efficacious treatment remains largely unmet. This review describes the currently available management options for FD and critically evaluates emerging therapies.

EXPERT OPINION

The optimal treatment for FD is yet to be determined. A proton pump inhibitor or a prokinetic agent constitutes primary treatment. Helicobacter pylori testing and eradication is recommended. Based on currently available data, acotiamide appears promising, particularly in postprandial distress syndrome. Further large-scale multicentered trials are required to define the duration of treatment and the side-effect profile.

Current and emerging pharmacotherapeutic options for irritable bowel syndrome

Treatment of irritable bowel syndrome (IBS) is challenging for both primary care physicians and gastroenterologists because of the heterogeneity of the patient population and the multifactorial pathophysiologies responsible for the symptoms in IBS. This review focuses on the current and emerging pharmacological treatments for IBS. Many of the current medications used to treat this disorder have distinct properties such as efficacy for different symptoms, safety profiles, contraindications, costs, dosing regimens, treatment duration and long-term data. All of these factors, in addition to patient preference and cognitive, food and environmental triggers, must be considered prior to any medication selection. This review will focus on randomized controlled trials with a general uniformity in study design, a rigorous patient selection and appropriate treatment durations. We will also discuss other exciting emerging treatments for IBS such as the µ-opioid receptor (agonists and antagonists), selective κ-opioid receptor agonists, anti-inflammatory drugs, serotonergic agents, bile acid modulators and intestinal bile acid transporters, which may prove promising in treating our patients.

Standardized herbal treatments on functional bowel disorders: moving from putative mechanisms of action to controlled clinical trials

Symptom relief in functional gastrointestinal disorders (FGID) is frequently sought with complementary and alternative medicine, and various herbal medicine compounds are popular in different parts of the world. Only a few products, however, are standardized and are backed by scientific evidence. This review mainly focuses on mechanistic and clinical data in support of the Japanese traditional compound Rikkunshi-to (RKT) and of STW-5. Their effects on gut sensori-motor function, neurohormonal network, and controlled clinical data in FGID are revised. RKT and STW-5 appear to possess some degree of gastroprokinetic, visceral analgesic properties, and seem to increase the gastric accommodation response. Controlled trials of RKT and STW-5 support at least a modest effect on symptoms of functional dyspepsia and irritable bowel syndrome, with low side effects profile. With the widespread use of herbals and the relative paucity of effective pharmacological options for FGID, rigorous studies to further elucidate pharmacological actions and clinical applications of herbal compounds are a priority.

Effect of hyoscine butylbromide (Buscopan®) on cholinergic pathways in the human intestine

BACKGROUND

Hyoscine butylbromide (HBB, Buscopan(®) ) is clinically used to treat intestinal cramps and visceral pain. Various studies, mainly on animal tissues, suggested that its antimuscarinic action is responsible for its spasmolytic effect. However, functional in vitro studies with human tissue have not been performed so far.

METHODS

We wanted to provide a comprehensive study on the mode of action of HBB in human intestinal samples and investigated HBB (1 nmol L(-1) -10 μmol L(-1)) effects on muscle activity with isometric force transducers and calcium imaging, on epithelial secretion with Ussing chamber technique and on enteric neurons using fast neuroimaging.

KEY RESULTS

Hyoscine butylbromide concentration dependently reduced muscle contractions, calcium mobilization, and epithelial secretion induced by the muscarinic agonist bethanechol with IC50 values of 429, 121, and 224 nmol L(-1), respectively. Forskolin-induced secretion was not altered by HBB. Cholinergic muscarinic muscle and epithelial responses evoked by electrical nerve stimulation were inhibited by 1-10 μmol L(-1) HBB. Moreover, HBB significantly reduced the bethanechol-induced action potential discharge in enteric neurons. Interestingly, we observed that high concentrations of HBB (10 μmol L(-1)) moderately decreased nicotinic receptor-mediated secretion, motility, and nerve activity.

CONCLUSIONS & INFERENCES

The results demonstrated the strong antimuscarinic action of HBB whereas the nicotinic antagonism at higher concentrations plays at most a moderate modulatory role. The muscle relaxing effect of HBB and its inhibition of muscarinic nerve activation likely explain its clinical use as an antispasmodic drug. Our results further highlight a so far unknown antisecretory action of HBB which warrants further clinical studies on its use in secretory disorders.

New treatments for IBS

IBS is a common disorder that affects approximately 5-20% of the populations of Western countries; the main symptoms are abdominal pain and erratic, altered bowel habits, often accompanied by bloating. Despite an array of available pharmacological and nonpharmacological treatments aimed at a wide variety of gastrointestinal and brain targets, many patients do not report adequate symptom relief. The effect of IBS on an individual can be enormous, and the societal and financial costs overall are high, which is indicative of an unmet need for effective IBS treatments. Intense research efforts are ongoing that range from the development of new molecules for pharmacological therapies to testing the utility of internet technology to facilitate widespread delivery of efficacious behavioural therapy. This Review discusses the latest treatments for IBS, including novel nonpharmacological and pharmacological approaches. We have included estimates of the number needed to treat and the number needed to harm for selected treatments. Emerging and potential future treatments are included, with the data supporting an optimistic view about the future of IBS therapeutics. The ability to optimize therapy by individualizing management whilst also avoiding harm remains the key to achieving the best possible outcomes with currently available therapeutics.

Phytotherapy of chronic abdominal pain following pancreatic carcinoma surgery: a single case observation

A patient with pancreatic carcinoma diagnosed in 2005 suffered from chronic abdominal pain 6 years later that did not respond to conventional pain treatment according to guidelines. Furthermore, several complementary medical approaches remained ineffective. In the long run, only an Iberis amara drug combination relieved pain sufficiently. The drug is registered in Germany for the indications irritable bowel syndrome and dyspepsia. The multi-target approach of this combination drug may account for the effectiveness under these fundamentally different pathophysiological conditions. No serious undesired effects have been described in the use of this drug for other indications and none were observed in this case.

Herbal medicines for the management of irritable bowel syndrome: A comprehensive review

Irritable bowel syndrome (IBS) is a functional gut disorder with high prevalence. Because of various factors involved in its pathophysiology and disappointing results from conventional IBS medications, the treatment of IBS is challenging and use of complementary and alternative medicines especially herbal therapies is increasing. In this paper, electronic databases including PubMed, Scopus, and Cochrane library were searched to obtain any in vitro, in vivo or human studies evaluating single or compound herbal preparations in the management of IBS. One in vitro, 3 in vivo and 23 human studies were included and systematically reviewed. The majority of studies are about essential oil of Menta piperita as a single preparation and STW 5 as a compound preparation. Some evaluated herbs such as Curcuma xanthorriza and Fumaria officinalis did not demonstrate any benefits in IBS. However, it seems there are many other herbal preparations such as those proposed in traditional medicine of different countries that could be studied and investigated for their efficacy in management of IBS.

Stimulation of murine intestinal secretion by daily genistein injections: gender-dependent differences

BACKGROUND/AIMS

The effect of daily injections with genistein (naturally occurring phytoestrogen) on intestinal chloride (Cl(-)) secretion was measured with Ussing chamber short circuit current (I(sc), μA/cm(2)), in C57BL/6J male and female mice, using 600 mg/kg genistein/day (600G), 300 mg/kg genistein/day (300G), 150 mg/kg genistein/day (150G) or genistein-free vehicle control (0G) for 1- or 2-weeks.

METHODS AND RESULTS

Injecting with 600G elicited significant increases in basal I(sc) in females after 1-week (ñ70 μA/cm(2), n=15, p < 0.05) and in males after 2-weeks (ñ80 μA/cm(2), n=5, p < 0.05) compared to their 0G counterparts. Chloride-free ringer significantly reduced basal I(sc) by 65% in 600G males and 72% in 600G females, suggesting that Cl(-) was the major anion comprising the genistein-stimulated secretion. The forskolin-stimulated (10 μM) I(sc) was significantly inhibited by the CFTR chloride channel inhibitors, glibenclamide (500 μM) and CFTR(inh)-172 (100 μM) in 600G males and females, suggesting some contribution by genistein-dependent CFTR-mediated Cl(-) secretion. We found no associated changes in intestinal morphology, nor change in total CFTR protein with 600G. There was a 5% increase in apical/subapical ratio in 600G males compared to controls (no change in females).

CONCLUSION

These data suggest that male and female mice both exhibit increased Cl- secretion with 600G, however, the mechanisms mediating this are gender-dependent.

The Size of the Papilla of Vater and Its Relation to Its Height in Comparison with the Visibility of the Sphincter of Oddi before and after Cholecystectomy

This study investigated the changes in the surface area and height of the papilla of Vater (PV) and the visibility of the sphincter of Oddi complex (SOK) using endoscopic ultrasound (EUS) examinations of 80 patients with symptomatic gallstones before and at 3 and 6 months after cholecystectomy. Following surgery, 50 patients experienced early atypical symptoms characteristic of postcholecystectomy syndrome (PCS) and 30 patients were asymptomatic. The PV measurements were greater in all patients compared with normal reference values and increased significantly from before surgery to 3 months postsurgery. At 6 months postsurgery, both the surface area and height of the PV had significantly decreased to preoperative values but remained higher than normal. The proportion of patients with a visible SOK had increased by 3 months postsurgery but had reduced again by 6 months. There were no significant differences between symptomatic and asymptomatic patients, suggesting that the changes observed in the PV and SOK do not explain the presence of the atypical symptoms of PCS.

Signaling mechanisms involved in the intestinal pro-secretory actions of hydrogen sulfide

BACKGROUND

H(2) S actions in the gut involve neural activation. This study aimed to reveal the signaling mechanisms responsible for the pro-secretory effect of H(2) S by using TRPV1 and unselective TRP blockers and inhibitors of other signaling cascades hitherto described to be targeted by H(2) S elsewhere.

METHODS

Ussing chamber voltage clamp technique was used to study actions of the H(2) S donor NaHS on secretion in guinea-pig and human colon. NaHS effects on guinea-pig primary afferents were also evaluated.

KEY RESULTS

NaHS evoked secretion was significantly reduced in guinea-pig and human tissue by the selective TRPV1 blockers capsazepine, AMG9801, SB705498, BCTC; LY294002 (Phosphatidylinositol-3 kinase (PI3K) inhibitor), SKF96365 (store operated calcium channel blocker), 2-APB (inositol triphosphate blocker), and atropine but not by HC030031 (TRPA1 blocker) or L- and T-type calcium channel antagonists. Actions of TRPV1 antagonists suggested non-competitive inhibition at multiple sites. In guinea-pig colon, Gd(3+) and La(3+) (unselective TRP blockers) had no effects while ruthenium red reduced NaHS effects; in human colon Gd(3+) attenuated NaHS response. NaHS response was inhibited by neurokinin-1 and -3 receptor blockers in guinea-pig and neurokinin-1 and -2 receptor blockade in human tissue. There was cross-desensitization between NaHS and capsaicin responses. NaHS induced capsazepine and LY294002 sensitive afferent discharge.

CONCLUSIONS & INFERENCES

H(2) S evokes mucosal secretion by targeting TRPV1 expressing afferent nerves which activate cholinergic secretomotor neurons via release of substance P acting in a species dependent manner on neurokinin-1, -2 or -3 receptors. Besides TRPV1 signaling H(2) S may target intracellular calcium dependent pathways and PI3K.

Irritable bowel syndrome: epidemiology, diagnosis and treatment: an update for health-care practitioners

Irritable bowel syndrome (IBS), a chronic gastrointestinal disorder, affects from 3-20% of the US population, depending on sociocultural and comorbid factors. IBS is characterized by a symptom complex of abdominal pain and abnormal bowel habits that present as diarrhea or constipation, and general physical weakness in the absence of abnormal morphological, histological or inflammatory markers. The main diagnostic Rome III criteria as established by international professional organizations are based on exclusion criteria and the occurrence and rate of symptoms. Because the pathophysiology and causes of IBS are poorly understood, treatment approaches are mainly focused on symptom management to maintain everyday functioning and improve quality of life for persons with IBS. The mainstay of intervention is pharmacological treatment with antispasmodics and antidiarrheals for diarrhea, prokinetics and high-fiber diets for constipation, and supportive therapy with low-dose antidepressants to normalize gastrointestinal motility. Other interventions include lifestyle and dietary changes, psychotherapy, herbal therapies and acupuncture. The purpose of this review is to critically assess benefits and risks of current treatment approaches as well as promising complementary and alternative therapies.