Region-specific effects of STW 5 (Iberogast) and its components in gastric fundus, corpus and antrum

Effect of Iberogast (STW5) on tolerance to colonic gas in patients with irritable bowel syndrome: A randomized, double-blind, placebo control clinical trial

BACKGROUND

STW5 is an herbal medicinal product that, in previous studies, reduced abdominal pain in irritable bowel syndrome (IBS). The effect of STW5 on gas-related abdominal symptoms is unknown.

AIM

To determine the effects of STW5, compared to placebo, on the responses to colonic gas in IBS.

METHODS

Using a cross-over design, two gas challenge tests were performed in 10 patients with IBS and bloating after 2-weeks treatment with (a) STW5 and (b) placebo. The challenge test consisted in continuous infusion of gas into the colon (24 mL/min for 60 min), followed by a 30-min free evacuation period. Gas evacuation, symptom perception, and abdominal distension were continuously registered.

RESULTS

Colonic gas filling was associated to a significant rise in abdominal symptom perception, that was significantly greater when patients were on-placebo (score increment 4.0 ± 0.3) compared with on-STW5 (score increment 3.2 ± 0.4; p = 0.035). Gas filling was associated to a progressive abdominal distension that was similar with both treatments. Opening of the rectal cannula produced a massive gas evacuation, similar after both treatments, associated to a return of abdominal perception and distension to basal levels when patients were on-STW5 (score increment -0.1 ± 0.4; distension 0.3 ± 0.2 cm; p = 0.399, and p = 0.112 vs. basal), whereas both remained increased on-placebo (score increment 0.5 ± 0.3; distension 0.8 ± 0.3 cm; p = 0.048, and p = 0.016 vs. infusion start).

CONCLUSIONS

STW5 improves colonic gas tolerance in IBS patients with bloating without a significant effect on gas retention and evacuation. This medicinal product can be beneficious for treatment of gas-related abdominal symptoms in patients with bloating. EudraCT: 2019-003976-38.

Mechanisms involved in the muscle relaxing effects of STW 5 in guinea pig stomach

INTRODUCTION

The herbal preparation STW 5 ameliorates functional dyspepsia partly by relaxing smooth muscle of the proximal stomach, thus improving gastric accommodation. We explored the unknown pathways responsible for this effect by testing targets known to modulate gastric smooth muscle relaxation.

METHODS

STW 5-induced relaxation of smooth muscle strips from guinea pig gastric corpus before and after pharmacological interventions were recorded with force transducers in an organ bath. ORAI1 mRNA expression was tested in the proximal stomach.

KEY RESULTS

Blockade of Ca2+ -activated K+ and Cl- channels, voltage-gated L- or T-type Ca2+ channels, TRPA1-, TRPV1-, adenosine or 5-HT4 receptors, antagonizing ryanodine receptors, inhibiting cyclooxygenase or sarcoplasmic reticulum calcium ATPase did not affect STW 5-evoked relaxation. Likewise, protein-kinase A or G were not involved. However, the relaxation evoked by STW 5 was significantly reduced by phorbol-12-myristat-13-acetat, an activator of protein-kinase C, by 2- aminoethyldiphenylborinate, an inhibitor of the IP3 receptor-mediated Ca2+ release from the sarcoplasmic reticulum or by SKF-96365, a nonselective store-operated calcium entry (SOCE) blocker. Furthermore, the mixed TRPC3/SOCE inhibitor Pyr3, but not the selective TRPC3 blocker Pyr10, reduced the effect of STW 5. Finally, BTP2, a potent blocker of ORAI-coupled SOCE, almost abolished STW 5-evoked relaxation. Expression of ORAI1 could be demonstrated in the corpus/fundus.

CONCLUSIONS & INFERENCES

STW 5 inhibited SOCE, most likely ORAI channels, which are modulated by IP3- and PKC-dependent mechanisms. Our findings impact on the design of drugs to induce muscle relaxation and help identify phytochemicals with similar modes of actions to treat gastrointestinal disturbances.

The herbal preparation, STW5-II, reduces proximal gastric tone and stimulates antral pressures in healthy humans

BACKGROUND

The herbal preparation, STW5-II, improves upper gastrointestinal symptoms, including abdominal fullness, early satiation, and epigastric pain, in patients with functional dyspepsia, and in preclinical models decreases fundic tone and increases antral contractility. The effects of STW5-II on esophago-gastric junction pressure, proximal gastric tone and antropyloroduodenal pressures, disturbances of which may contribute to symptoms associated with disorders of gut-brain interaction, including functional dyspepsia, in humans, have, hitherto, not been evaluated.

METHODS

STW5-II or placebo (matched for color, aroma, and alcohol content) were each administered orally, at the recommended dose (20 drops), to healthy male and female volunteers (age: 27 ± 1 years) in a double-blind, randomized fashion, on two separate occasions, separated by 3-7 days, to evaluate effects on (i) esophago-gastric junction pressures following a standardized meal using solid-state high-resolution manometry (part 1, n = 16), (ii) proximal gastric volume using a barostat (part 2, n = 16), and (iii) antropyloroduodenal pressures assessed by high-resolution manometry (part 3, n = 18), for 120 min (part 1) or 180 min (parts 2, 3).

KEY RESULTS

STW5-II increased maximum intrabag volume (ml; STW5-II: 340 ± 38, placebo: 251 ± 30; p = 0.007) and intrabag volume between t = 120 and 180 min (p = 0.011), and the motility index of antral pressure waves between t = 60 and 120 min (p = 0.032), but had no effect on esophago-gastric junction, pyloric, or duodenal pressures.

CONCLUSIONS & INFERENCES

STW5-II has marked region-specific effects on gastric motility in humans, which may contribute to its therapeutic efficacy in functional dyspepsia.

The Effect of STW5 (Iberogast) on Reflux Symptoms in Patients With Concurrent Dyspeptic Symptoms: A Double-blind Randomized Placebo-controlled Crossover Trial

Background/Aims

It has been suggested that STW5 (Iberogast) reduces heartburn symptoms in patients with functional dyspepsia, but underlying mechanisms of action are unclear. The aim of this study is to investigate whether STW5 affects esophageal sensitivity or esophageal motility, thereby reducing occurrence and perception of reflux events.

Methods

We performed a double-blind, randomized, placebo-controlled, crossover trial in patients with functional dyspepsia (Rome IV) and reflux symptoms. After 4 weeks of treatment with either placebo or STW5, patients were studied with an esophageal acid perfusion test and ambulatory 24-hour pH-impedance monitoring.

Results

A total of 18 patients (7 men, median age 54, range [19-76]), were included in the study. Although we found no statistical difference in our primary outcome the total Reflux Disease Questionnaire score 2.33 (0.25-4.33) vs 2.67 (1.17-4.00), P = 0.347, "gastroesophageal reflux disease" and "regurgitation" subscale scores were lower after STW5 treatment compared to placebo (P = 0.049 and P = 0.007). There was no statistical difference in number of reflux events, acid exposure time and acid sensitivity scores between STW5 and placebo. In a subgroup analysis of patients with pH-metry confirmed gastroesophageal reflux disease, treatment with STW5 significantly reduced the total number of acidic reflux events (P = 0.028). Moreover, in patients with reflux esophagitis, the median lag time to acid perception increased after STW5 treatment (P = 0.042).

Conclusions

We found some indications pointing towards a beneficial effect of STW5 on reflux symptoms in dyspeptic patients, with reduction of esophageal hypersensitivity as a potential underlying mechanism. Our findings will have to be confirmed in larger studies.

Nutraceuticals and Pain Disorders of the Gut-Brain Interaction in Infants and Children: A Narrative Review and Practical Insights

Different nutraceuticals are often considered by parents of infants and children with abdominal pain and disorders of the gut-brain interaction. Herb extracts and natural compounds have long been used in traditional medicine, but clinical pediatric trials are very limited. This narrative review based on relevant studies identified through a search of the literature in Pubmed and Medline updated to October 2023 focused on the effect of nutraceuticals in infantile colic, functional abdominal pain, and irritable bowel syndrome in children and adolescents. Significant reductions in colic episodes and crying time were reported in two studies on fennel (seeds oil or tea), in three studies on different multiple herbal extracts (all including fennel), in one study on Mentha piperita, and in at least two double-blind randomized controlled studies on Lactobacillus reuteri DSM 17938 and Bifidobacterium lactis BB-12 (108 CFU/day for at least 21 days) in breast-fed infants. Compared to a placebo, in children with functional abdominal pain or irritable bowel syndrome, a significant reduction in pain was reported in two studies supplementing peppermint oil capsules or psyllium fibers, and in one study on corn fiber cookies, partial hydrolyzed guar gum, a specific multiple herbal extract (STW-5), or vitamin D supplementation. To date, there is moderate-certainty evidence with a weak grade of recommendation on Lactobacillus reuteri DSM 17938 (108 CFU/day) in reducing pain intensity in children with functional abdominal pain and for Lactobacillus rhamnosus GG (1-3 × 109 CFU twice daily) in reducing pain frequency and intensity in children with IBS. Further large and well-designed pediatric studies are needed to prove the efficacy and safety of different herbal extracts and prolonged use of studied products in infants and children with pain disorders of the gut-brain interaction.

Short- and Long-Term Effects of Cocaine on Enteric Neuronal Functions

Cocaine is one of the most consumed illegal drugs among (young) adults in the European Union and it exerts various acute and chronic negative effects on psychical and physical health. The central mechanism through which cocaine initially leads to improved performance, followed by addictive behavior, has already been intensively studied and includes effects on the homeostasis of the neurotransmitters dopamine, partly mediated via nicotinic acetylcholine receptors, and serotonin. However, effects on the peripheral nervous system, including the enteric nervous system, are much less understood, though a correlation between cocaine consumption and gastrointestinal symptoms has been reported. The aim of the present study was to gain more information on the effects of cocaine on enteric neuronal functions and the underlying mechanisms. For this purpose, functional experiments using an organ bath, Ussing chamber and neuroimaging techniques were conducted on gastrointestinal tissues from guinea pigs. Key results obtained are that cocaine (1) exhibits a stimulating, non-neuronal effect on gastric antrum motility, (2) acutely (but not chronically) diminishes responses of primary cultured enteric neurons to nicotinic and serotonergic stimulation and (3) reversibly attenuates neuronal-mediated intestinal mucosal secretion. It can be concluded that cocaine, among its central effects, also alters enteric neuronal functions, providing potential explanations for the coexistence of cocaine abuse and gastrointestinal complaints.

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.

Herbal Approaches to Pediatric Functional Abdominal Pain

Chronic abdominal pain is one of the most common problems seen by both pediatricians and pediatric gastroenterologists. Abdominal-pain-related functional gastrointestinal disorders (AP-FGIDs) are diagnosed in children with chronic and recurrent abdominal pain meeting clinical criteria set forth in the Rome IV criteria. AP-FGIDs affect approximately 20% of children worldwide and include functional dyspepsia (FD), irritable bowel syndrome (IBS), functional abdominal pain (FAP), and abdominal migraine. IBS accounts for 45% of pediatric AP-FGIDs. The pathophysiology of functional abdominal pain involves an interplay of factors including early life events, genetics, psychosocial influences, and physiologic factors of visceral sensitivity, motility disturbance, altered mucosal immune function, and altered central nervous system processing. Treatment approaches are varied and can include dietary, pharmacologic, and complementary medicine interventions, as well as psychosocial support, depending on the many aspects of the disorder and the needs of the individual patient. There is a strong interest in complementary and integrative medicine approaches to pediatric pain from both patients, providers, and families. In this article, we discuss popular herbal treatments typically used in the field of complementary medicine to treat pediatric AP-FGIDs: peppermint oil, Iberogast^®, cannabis, fennel, and licorice. While high-quality data are rather limited, studies generally show that these remedies are at least as effective as placebo, and are well tolerated with minimal side effects. We will need more placebo-controlled, double-blind, and unbiased prospective studies to document and quantify efficacy.

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.

Peppermint and caraway oils have muscle inhibitory and pro-secretory activity in the human intestine in vitro

BACKGROUND

Herbal medicinal products with a broad activity spectrum may be promising alternatives to treat functional gastrointestinal disorders (FGD). Menthacarin^® is a drug with a fixed combination of peppermint and caraway oils, which is clinically used to treat FGD-associated symptoms.

MATERIALS

We studied the effects of peppermint and caraway oils on contractile and secretory activity in 255 human small and large intestinal preparations derived from surgical resections (73 patients). Motility was recorded in circular smooth muscle strips and secretion with the Ussing chamber-voltage clamp technique. Electrical field stimulation evoked nerve induced contractile responses. KEY RESULTS: Peppermint and caraway oil concentrations dependently inhibited muscle contractility as indicated by sustained muscle relaxation and decrease in phasic contractility. These effects occurred in small and large intestinal preparations with IC₅₀ values ranging between 17 and 90 µg/mL for peppermint oil and between 7 and 127 µg/mL for caraway oil. Neither peppermint nor caraway oil influenced the nerve evoked contractile response. The inhibition of contractile activity, but not the muscle relaxation, was prevented by the L-type calcium channel activator Bay K8644 but not by the neurotoxin tetrodotoxin. Both peppermint oil and caraway oil increased epithelial secretion, which remained in tetrodotoxin.

CONCLUSION & INTERFERENCE

The findings revealed a strong muscle inhibitory and pro-secretory action of peppermint and caraway oils at clinically relevant concentrations. Both actions were nerve-independent. The inhibition of contractility was mediated by inhibition of L-type calcium channels. The effects on muscle and epithelial activity may contribute to the beneficial effects observed in patients with FGD.

Herbal Therapies in Functional Gastrointestinal Disorders: A Narrative Review and Clinical Implication

The pathophysiology of functional gastrointestinal disorders (FGIDs) is still unclear and various complex mechanisms have been suggested to be involved. In many cases, improvement of symptoms and quality of life (QoL) in patients with FGIDs is difficult to achieve with the single-targeted treatments alone and clinical application of these treatments can be challenging owing to the side effects. Herbal preparations as complementary and alternative medicine can control multiple treatment targets of FGIDs simultaneously and relatively safely. To date, many herbal ingredients and combination preparations have been proposed across different countries and together with a variety of traditional medicine. Among the herbal therapies that are comparatively considered to have an evidence base are iberogast (STW-5) and peppermint oil, which have been mainly studied and used in Europe, and rikkunshito and motilitone (DA-9701), which are extracted from natural substances in traditional medicine, are the focus of this review. These herbal medications have multi-target pharmacology similar to the etiology of FGIDs, such as altered intestinal sensory and motor function, inflammation, neurohormonal abnormality, and have displayed comparable efficacy and safety in controlled trials. To achieve the treatment goal of refractory FGIDs, extensive and high quality studies on the pharmacological mechanisms and clinical effects of these herbal medications as well as efforts to develop new promising herbal compounds are required.

Synergy quantifications to identify individual contributions of combination partners to the overall activity - The example of STW 5

BACKGROUND

The rationale of combinations of plant extracts is often questioned. The common argument for combinations is a higher efficacy of the combination partners by multitargeting and the elimination of adverse events.

AIM

STW5, a well-known fixed herbal multicomponent preparation, is recommended in the German treatment guidelines for functional gastrointestinal diseases. The study assessed effects of STW5, its single plant components and combinations thereof on different targets to identify synergistic, additive or antagonistic effects of the combination partners.

STUDY DESIGN/METHODS

STW5, its nine components and triple combinations thereof were investigated in two in vitro models - human esophageal epithelial cells (Het1A) and intestinal smooth muscle cells (HISMC) - in comparison to Omeprazole (OM) for the release of interleukin 8 (IL-8) as surrogate for inflammation and of Ca²⁺ as surrogate for motion, under non-inflammatory and inflammatory (Capsaicin 80 µM (CAP)) conditions. The combination index (CI) of triple combinations was calculated to assess synergistic, antagonistic and additive effects.

RESULTS

In Het-1A cells, STW5 showed, under non-inflammatory as well as inflammatory conditions, releases of IL-8 (49.3 ± 4.2 pg/ml, 33.7 ± 2 pg/ml) comparable to the untreated control (46.3 ± 4.8 pg/ml). CAP increased IL-8 releases to 85.8 ± 14 pg/ml (p < 0.005). Among the single plant extracts the Iberis amara extract (IBE) induced high IL-8 releases under non-inflammatory (441 ± 177 pg/ml) and inflammatory (625± 121 pg/ml) conditions. The Silybum marianum (L.) extract (SM) reduced releases up to 20.1 ± 8 pg/ml (inflammation). The CI-values of triple combinations with IBE ranged from high synergy (CI<0.03) to antagonism (CI:480). Within the triple combinations SM was the most effective combination partner to reduce IL-8. The combination of Angelica archangelica (L.)/Carum carvi (L.) was also effective. In HISMCs, STW5 induced concentration dependent higher Ca²⁺-releases. Only Melissa officinalis (L.) (MO) induced high Ca²⁺- releases in HISMCs.

CONCLUSION

In Het-1A, STW5 inhibited Il-8 releases, although one of its components (IBE) stimulated IL-8 strongly. The combination partners in STW5 assured an overall marked anti-inflammatory action. In the triple combinations SM was identified as most important combination partner for the IL-8 reduction. CI-measurements can support the identification of active combination partners in a multicomponent preparation and can give directions towards the search for multitarget effects.

Review article: treatment options for functional dyspepsia

BACKGROUND

Functional dyspepsia, consisting of epigastric pain syndrome and postprandial distress syndrome, is a prevalent functional gastrointestinal disorder. To date, only limited treatment options are available and conflicting results in terms of efficacy have been reported. Consequently, nonpharmacological treatment options are increasingly being explored for functional dyspepsia.

AIM

To provide an overview of current pharmacological and nonpharmacological treatment options for functional dyspepsia.

METHODS

A literature search was conducted on Pubmed and other sources to identify relevant studies.

RESULTS

Acid suppressive therapy reduced symptoms in 30%-70% of the patients, with higher benefit in epigastric pain syndrome and superior effectiveness for proton pump inhibitors compared to H₂ -antagonists. Prokinetic agents, primarily used to treat postprandial distress syndrome, showed variable efficiency: 59%-81% responder rate for dopamine receptor antagonists, 32%-91% for serotonin-4-receptor agonists and 31%-80% for muscarinic receptor antagonists. H Pylori eradication, recommended in infected patients, was effective in 24%-82%. Refractory symptoms are addressed with neuromodulators. However, their efficacy in functional dyspepsia remains incompletely elucidated, available data showing symptom reduction in 27%-71% of the patients. Regarding herbal agents, peppermint oil reduced symptoms in 66%-91%, rikkunshito in 29%-34% and iberogast in 20%-95%. Lastly, acupuncture, cognitive behavioural therapy and hypnotherapy may help to provide symptom control, but research on their efficacy remains sparse.

CONCLUSIONS

None of the available therapies is effective in the majority of patients without being associated with major side effects. Developing new treatment options is challenging due to the heterogeneity of functional dyspepsia, the lack of readily identified target mechanisms and the poor association between pathophysiological disturbances and symptoms.

Basal and Spasmolytic Effects of a Hydroethanolic Leaf Extract of Melissa officinalis L. on Intestinal Motility: An Ex Vivo Study

Melissa officinalis L. (lemon balm) has been used for decades with symptomatic benefits in patients with digestive disorders. However, very little is known on the effects of M. officinalis on the gastrointestinal (GI) tract. In this study, the basal and spasmolytic properties of a hydroethanolic leaf extract (HLE) of M. officinalis were assessed ex vivo on different segments of the GI tract of mice after phytochemical characterization of the extract. M. officinalis HLE had site- and dose-dependent effects on the contractile activity of the GI tract, the motility response being impacted in the jejunum and ileum but not in the antrum and colon. The observed effects could be caused by the phenolic compounds (mainly rosmarinic acid) detected in the extract.

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.

Early onset of efficacy in patients with functional and motility-related gastrointestinal disorders : A noninterventional study with Iberogast®

STW 5 (Iberogast®; Steigerwald Arzneimittelwerk GmbH, Darmstadt, Germany) contains nine plant extracts and possesses well-documented overall efficacy in functional gastrointestinal disorders (FGID). Little is known about the onset of symptom relief. Twenty-nine centers in Germany recruited 272 patients with established FGID. These patients were treated with STW 5 for approximately 3 weeks in this noninterventional study. Patients assessed the severity of their gastrointestinal complaints before and at defined times after the intake of STW 5 (10 cm visual analogue scale; VAS). Fifteen minutes after the first dose, the severity of gastrointestinal complaints had decreased by 1.4 cm (mean; initial mean: 5.2 of 10 cm). After 1 h, more than 90% of the maximum effect of 3.2 cm on the 10 cm VAS had been reached. Most patients with symptoms experienced a marked improvement within 5, 15 or 30 min of taking STW 5. Absolute improvements were larger in patients with more pronounced baseline complaints. Subgroups with upper (80% of the study population) and lower FGID (20%) did not present major differences. Neither did subgroups by age and duration of complaints. Treatment with STW 5 resulted in rapid improvement of symptoms.

Modulation of gastrointestinal motility beyond metoclopramide and domperidone : Pharmacological and clinical evidence for phytotherapy in functional gastrointestinal disorders

The prokinetic cisapride, an important therapeutic option in functional gastrointestinal (GI) disorders, was withdrawn from the market 15 years ago due to rare severe side effects. Likewise in 2014, the use of metoclopramide (MCP) and domperidone in functional GI disorders (FGID) was restricted, consequently leaving a therapeutic gap in clinical practice. A systematic review revealed that the herbal medicinal product (HMP) STW 5 presents a therapeutic option equivalent to MCP and cisapride. STW 5 is the only HMP for which efficacy has been shown in randomized controlled clinical trials (RCTs) in functional dyspepsia and irritable bowel syndrome, based on its multitarget effect on numerous etiological factors. Due to an outstanding favorable safety profile, STW 5 allows an effective and safe use in FGID without a limitation of the duration of the treatment.

Medicinal plants--prophylactic and therapeutic options for gastrointestinal and respiratory diseases in calves and piglets? A systematic review

BACKGROUND

Gastrointestinal and respiratory diseases in calves and piglets lead to significant economic losses in livestock husbandry. A high morbidity has been reported for diarrhea (calves ≤ 35%; piglets ≤ 50%) and for respiratory diseases (calves ≤ 80%; piglets ≤ 40%). Despite a highly diverse etiology and pathophysiology of these diseases, treatment with antimicrobials is often the first-line therapy. Multi-antimicrobial resistance in pathogens results in international accordance to strengthen the research in novel treatment options. Medicinal plants bear a potential as alternative or additional treatment. Based on the versatile effects of their plant specific multi-component-compositions, medicinal plants can potentially act as 'multi-target drugs'. Regarding the plurality of medicinal plants, the aim of this systematic review was to identify potential medicinal plant species for prevention and treatment of gastrointestinal and respiratory diseases and for modulation of the immune system and inflammation in calves and piglets.

RESULTS

Based on nine initial sources including standard textbooks and European ethnoveterinary studies, a total of 223 medicinal plant species related to the treatment of gastrointestinal and respiratory diseases was identified. A defined search strategy was established using the PRISMA statement to evaluate 30 medicinal plant species starting from 20'000 peer-reviewed articles published in the last 20 years (1994-2014). This strategy led to 418 references (257 in vitro, 84 in vivo and 77 clinical trials, thereof 48 clinical trials in veterinary medicine) to evaluate effects of medicinal plants and their efficacy in detail. The findings indicate that the most promising candidates for gastrointestinal diseases are Allium sativum L., Mentha x piperita L. and Salvia officinalis L.; for diseases of the respiratory tract Echinacea purpurea (L.) MOENCH, Thymus vulgaris L. and Althea officinalis L. were found most promising, and Echinacea purpurea (L.) MOENCH, Camellia sinensis (L.) KUNTZE, Glycyrrhiza glabra L. and Origanum vulgare L. were identified as best candidates for modulation of the immune system and inflammation.

CONCLUSIONS

Several medicinal plants bear a potential for novel treatment strategies for young livestock. There is a need for further research focused on gastrointestinal and respiratory diseases in calves and piglets, and the findings of this review provide a basis on plant selection for future studies.

Chinese Herbal Medicine for Functional Abdominal Pain Syndrome: From Clinical Findings to Basic Understandings

Functional abdominal pain syndrome (FAPS) is one of the less common functional gastrointestinal disorders. Conventional therapy has unsatisfactory response to it so people turn to Chinese medicine for help. Currently, we reviewed the whole picture of Chinese herbal medicine (CHM) clinical and basic application in the treatment of FAPS, especially the traditional Chinese medicine (TCM) syndrome, the single herb, and Chinese medicine formulae, thus to provide a solid base to further develop evidence-based study for this common gastrointestinal complaint in the future. We developed the search strategy and set the inclusion and exclusion criteria for article search. From the included articles, we totally retrieved 586 records according to our searching criteria, of which 16 were duplicate records and 291 were excluded for reasons of irrelevance. The full text of 279 articles was retrieved for detailed assessment, of which 123 were excluded for various reasons. The number one used single herb is Radix Ginseng. The most common syndrome was liver qi depression. The most frequently used classic formula was Si-Mo-Tang. This reflected the true situation of clinical practice of Chinese medicine practitioners and could be further systematically synthesized as key points of the therapeutic research for FAPS.

Effect of Imperatorin on the Spontaneous Motor Activity of Rat Isolated Jejunum Strips

Imperatorin, a psoralen-type furanocoumarin, is a potent myorelaxant agent acting as a calcium antagonist on vascular smooth muscle. Its effects on other types of smooth muscle remain unknown. Therefore, the aim of this study was to investigate the hypothesized myorelaxant effect of imperatorin on gut motor activity and, possibly, to define the underlying mechanism of action. Imperatorin was made available for pharmacological studies from the fruits of the widely available Angelica officinalis through the application of high-performance countercurrent chromatography (HPCCC). Imperatorin generated reversible relaxation of jejunum strips dose-dependently (1–100 μM). At 25 and 50 μM, imperatorin caused relaxation comparable to the strength of the reaction induced by isoproterenol (Isop) at 0.1 μM. The observed response resulted neither from the activation of soluble guanylate cyclase, nor from β-adrenoreceptor involvement, nor from Ca²⁺-activated potassium channels. Imperatorin relaxed intestine strips precontracted with high potassium concentration, attenuated the force and duration of K⁺-induced contractions, and modulated the response of jejunum strips to acetylcholine. The results suggest that imperatorin probably interacts with various Ca²⁺ influx pathways in intestine smooth muscle. The types of some calcium channels involved in the activity of imperatorin will be examined in a subsequent study.

The Pharmacological Effects of Benachio-F(®) on Rat Gastrointestinal Functions

Functional dyspepsia (FD) is a prevalent idiopathic upper gastrointestinal (GI) disorder characterized by diverse symptomatology including epigastric pain or discomfort, postprandial fullness, and early satiety. Although its pathophysiological mechanisms have not yet been fully established, the available studies suggest that the etiology of FD is invariably multifactorial. Benachio-F(®) (BF) is a proprietary liquid formulation of 7 herbal extracts that has been proposed to address this multifactorial etiology using multi-drug phytotherapy. The pharmacological effects of BF, in comparison with those of two other herbal products (Whalmyungsu(®); WM and Iberogast(®); IB) were evaluated in rats. In a laparotomy-induced rat model of delayed GI transit, BF significantly accelerated the delayed gastric emptying caused by morphine, apomorphine, and cisplatin, and also significantly increased mean gastric transit, as compared to the control animals. BF markedly increased gastric accommodation in rats and produced higher gastric volume values than did the control treatment. The effects of BF were generally comparable or superior to those of WM and IB in these models. Furthermore, BF significantly stimulated biliary flow, as compared to the control treatment. These results indicated that BF might have great potential as an effective phytotherapeutic agent capable of reducing GI symptoms and increasing quality of life in FD patients.

Novel sequential stress model for functional dyspepsia: Efficacy of the herbal preparation STW5

BACKGROUND

Many screening procedures for agents with potential usefulness in functional dyspepsia (FD) rely on animals exposed to stress early in life (neonatal maternal separation, NMS) or in adulthood (restraint stress, RS).

PURPOSE

Since many clinical cases of FD have been associated with stress in early life followed by stress in adulthood, a sequential model simulating the clinical situation is described. To explore the validity of the model, the efficacy of STW5, a multicomponent herbal preparation of proven usefulness in FD, was tested.

STUDY DESIGN/METHODS

A sequential stress model established where rats are exposed to NMS after birth followed later by RS in adulthood. Stress hormones and ghrelin were measured in plasma, while responsiveness of stomach fundus strips to smooth muscle stimulants and relaxants was assessed ex-vivo. The effectiveness of treatment with STW5 a few days before and during exposure to RS in preventing changes induced by the stress model is reported and compared to its efficacy when used in animals subjected to RS alone.

RESULTS

Responses to both stimulants and relaxants were reduced to various extents in the studied models, but treatment with STW5 tended to normalize gastric responsiveness. Plasma levels of ghrelin, corticosterone releasing factor, and corticosterone were raised by RS as well as the sequential model. Treatment with STW5 tended to prevent the deranged parameters.

CONCLUSION

The sequential stress model has a place in drug screening for potential usefulness in FD as it simulates more the clinical setting. Furthermore, the findings shed more light on the mechanisms of action of STW5 in FD.

Isolation and evaluation of the myorelaxant effect of bergapten on isolated rat jejunum

CONTEXT

Plants of the genus Heracleum L. (Apiaceae) have a long history of being used in traditional medicines for the treatment of alimentary tract disorders, and these biological effects have been ascribed to the presence of furanocoumarins (including bergapten).

OBJECTIVES

This study aimed to develop an efficient, preparative, counter-current chromatographic separation of bergapten in order to characterize its spasmolytic activity in isolated rat jejunum strips.

MATERIALS AND METHODS

Successful separation of the dichloromethane extract of the fruits of Heracleum leskovii Grossh. was achieved by high-performance countercurrent chromatography (HPCCC) using a two-phase solvent system composed of n-heptane/EtOAc/MeOH/H2O (6:5:6:5, v/v/v/v). The pharmacological assessment of bergapten (0.0001-50 μM) on jejunum smooth muscle strips isolated from rats was conducted under isotonic conditions, following up to three hours of incubation.

RESULTS

The separation method was scaled up six-fold from analytical to semi-preparative conditions, affording bergapten of >99% purity in less than 30 min. This permitted bergapten to be available in quantity for spasmolytic tests on isolated jejunum strips from rats. Bergapten caused myorelaxation of the intestine preparations in the concentration range of 0.0001-1 μM. At higher doses, bergapten caused either relaxation or contraction of the smooth muscle.

DISCUSSION AND CONCLUSION

Bergapten was successfully isolated by rapid HPCCC and its spasmolytic activity was confirmed, thereby providing a preliminary evidence base for the traditional medicine application. The data suggest that bergapten causes no irreversible changes to intestinal tissue.

Herbal medicines for the treatment of functional and inflammatory bowel disorders

In many parts of the world, there continues to be a long-standing tradition of prescribing herbal products for a range of gastrointestinal conditions. Scientific evidence supporting the use of all herbal preparations is imperfect, however, and available studies are plagued by methodological limitations. For functional gastrointestinal disorders, there is limited evidence supporting the use of some well-characterized preparations. A number of herbals have immunomodulatory activity, and in inflammatory bowel disease there are limited positive placebo-controlled trials; other studies used active controls with suboptimal doses of the comparators. Like all drugs, herbals can lead to serious adverse events (eg, hepatic failure). Quality control is a serious issue to consider when prescribing herbal medicines. Many herbal preparations are marketed without evidence for stringent adherence to good manufacturing practice guidelines. Unpredictable environmental conditions may affect the composition and the concentration of the active ingredients of plant extracts. Further, commercial herbal products usually combine a variable plethora of chemical families with possible medicinal utility. While some of these ingredients might be of benefit, the concentration and dose of these constituents needs to be closely monitored. Physicians and regulators need to remain very cautious about the use of herbal remedies. Appropriate scientific evidence for the claimed clinical benefits should become mandatory worldwide, and the standards for production and safety monitoring should comply with established standards for chemically defined products. If these principles were adopted, the full value of herbal remedies may come to light, particularly as the individually bioactive compounds present in these preparations become recognized.

Role of transient receptor potential channels in intestinal inflammation and visceral pain: novel targets in inflammatory bowel diseases

Transient receptor potential (TRP) channels are a large group of ion channels that are prevalent in mammalian tissues. They are widely distributed in the central and peripheral nervous systems, and in nonneuronal cells, where they are implicated in sensing temperature, noxious substances, and pain. TRPs play an important role in immune response and nociception and, therefore, may be involved in the pathogenesis of inflammatory bowel diseases, whose major symptoms include chronic inflammatory state and abdominal pain. In this review, we summarize what is known on TRP channels in inflammatory bowel disease and visceral pain; we focus in particular on TRPV1, TRPV4, TRPA1, and TRPM. We also analyze scientific reports that evidence potential use of TRP regulators in future inflammatory bowel disease treatment.

DA-9701: A New Multi-Acting Drug for the Treatment of Functional Dyspepsia

Motilitone^® (DA-9701) is a new herbal drug that was launched for the treatment of functional dyspepsia in December 2011 in Korea. The heterogeneous symptom pattern and multiple causes of functional dyspepsia have resulted in multiple drug target strategies for its treatment. DA-9701, a compound consisting of a combination of Corydalis Tuber and Pharbitidis Semen, has being developed for treatment of functional dyspepsia. It has multiple mechanisms of action such as fundus relaxation, visceral analgesia, and prokinetic effects. Furthermore, it was found to significantly enhance meal-induced gastric accommodation and increase gastric compliance in dogs. DA-9701 also showed an analgesic effect in rats with colorectal distension induced visceral hypersensitivity and an antinociceptive effect in beagle dogs with gastric distension-induced nociception. The pharmacological effects of DA-9701 also include conventional effects, such as enhanced gastric emptying and gastrointestinal transit. The safety profi le of DA-9701 is also preferable to that of other treatments.

Clinical and structural effects of traditional Chinese medicine and the herbal preparation, Iberogast, in a rat model of ulcerative colitis

Plant-sourced formulations such as Iberogast and the traditional Chinese medicine formulation, Cmed, purportedly possess anti-inflammatory and radical scavenging properties. We investigated Iberogast and Cmed, independently, for their potential to decrease the severity of the large bowel inflammatory disorder, ulcerative colitis. Sprague Dawley rats (n = 8/group) received daily 1 mL gavages (days 0-13) of water, Iberogast (100 μL/200 μL), or Cmed (10 mg/20 mg). Rats ingested 2% dextran sulfate sodium or water ad libitum for 7 days commencing on day 5. Dextran sulfate sodium administration increased disease activity index scores from days 6 to 12, compared with water controls (P < .05). On day 10, 200 μL Iberogast decreased disease activity index scores in colitic rats compared with colitic controls (P < .05). Neither Iberogast nor Cmed achieved statistical significance for daily metabolic parameters or colonic crypt depth. The therapeutic effects of Iberogast and Cmed were minimal in the colitis setting. Further studies of plant extracts are required investigating greater concentrations and alternative delivery systems.

Tibetan herbal formula Padma Digestin modulates gastrointestinal motility in vitro

AIM: To examine the effects of Padma Digestin on the smooth muscle motility of different gastrointestinal segments in vitro.

METHODS: The effects of the ethanolic extract of Padma Digestin (at 8.16 mg/mL or 81.6 mg/mL) on the contractility and susceptibility to acetylcholine (ACh) of muscle strips from the cardia, antrum, pylorus, duodenum, jejunum, ileum and colon of male Wistar rats were analyzed.

RESULTS: Compared with the control treatment, the Padma Digestin extract had a procontractile effect on the antral smooth muscle strips. Padma Digestin decreased ACh sensitivity in cardia muscle strips and increased it in those from the antrum and pylorus. In the intestinal segments, spontaneous contractility was inhibited in both the duodenal and jejunal strips, whereas reactivity to ACh was inhibited in the jejunal strips only. In the colonic samples, Padma Digestin inhibited spontaneous and ACh-stimulated contractility at a low dose but seems to have increasing effects at a high dose.

CONCLUSION: Padma Digestin extract has region-specific effects on the contractility and excitability of gastrointestinal smooth muscle. Our results support the traditional use of Padma Digestin for maldigestion and functional gastrointestinal disorders.

Simo Decoction Stimulates Contractions of Antral Longitudinal Smooth Muscle via Multitudinous Mechanisms

The aim of the study was to investigate Simo decoction–induced contractions of antral smooth muscles of rats and its mechanisms. The contractile responses of longitudinal strips to consecutive concentrations of Simo decoction were characterized by atropine, gallamine, 4-diphenylacetoxy-N-methylpiperidine methiodide, and adrenaline, hexamethonium, L-arginine, and nifedipine and compared with Krebs solution (control) and acetylcholine-induced contractions. Simo decoction dose-dependently increased contractions of antral strips ( P = .000 vs control); its maximal effect was higher than acetylcholine (10−3 mol L−1; P < .05); Simo decoction–induced contractions were completely inhibited by atropine, 4-diphenylacetoxy-N-methylpiperidine methiodide, or 4-diphenylacetoxy-N-methylpiperidine methiodide + gallamine ( P = .000 for all) but were partly suppressed by gallamine, adrenaline, hexamethonium, L-arginine, and nifedipine ( P = .000 for all). Simo decoction promotes the contractions of antral strips mainly through activation of muscarinic M3 receptor, while partly through activation of M2 receptor, Ca2+ channel, nicotinic receptor, and inhibition of adrenergic receptor as well as release of nitric oxide.

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.

In-vitro characterization of the pharmacological effects induced by (-)-α-bisabolol in rat smooth muscle preparations

The present study deals with the pharmacological effects of the sesquiterpene alcohol (-)-α-bisabolol on various smooth-muscle preparations from rats. Under resting tonus, (-)-α-bisabolol (30-300 µmol/L) relaxed duodenal strips, whereas it showed biphasic effects in other preparations, contracting endothelium-intact aortic rings and urinary bladder strips, and relaxing these tissues at higher concentrations (600-1000 µmol/L). In preparations precontracted either electromechanically (by 60 mmol/L K(+)) or pharmacomechanically (by phenylephrine or carbachol), (-)-α-bisabolol showed only relaxing properties. The pharmacological potency of (-)-α-bisabolol was variable, being higher in mesenteric vessels, whereas it exerted relaxing activity with a lesser potency on tracheal or colonic tissues. In tissues possessing spontaneous activity, (-)-α-bisabolol completely decreased spontaneous contractions in duodenum, whereas it increased their amplitude in urinary bladder tissue. Administered in vivo, (-)-α-bisabolol attenuated the increased responses of carbachol in tracheal rings of ovalbumin-sensitized rats challenged with ovalbumin, but was without effect in the decreased responsiveness of urinary bladder strips in mice treated with ifosfamide. In summary, (-)-α-bisabolol is biologically active in smooth muscle. In some tissues, (-)-α-bisabolol preferentially relaxed contractions induced electromechanically, especially in tracheal smooth muscle. The findings from tracheal rings reveal that (-)-α-bisabolol may be an inhibitor of voltage-dependent Ca(2+) channels.

Protective effect of Melissa officinalis aqueous extract against Mn-induced oxidative stress in chronically exposed mice

Manganese (Mn) is an essential element for biological systems; however occupational exposure to high levels of this metal may lead to neurodegenerative disorders, resembling Parkinson's disease (PD). While its mechanisms of neurotoxicity have yet to be fully understood, oxidative stress plays a critical role. Thus, the main goal of this study was to investigate the efficacy of aqueous extract of Melissa officinalis in attenuating Mn-induced brain oxidative stress in mice. Sixteen male mice were randomly divided into two groups and treated for 3 months: the first group consumed tap water (control group) and the second group was treated with Mn (50 mg/kg/day for habituation during the first 15 days followed by 100 mg/kg/day for additional 75 days) in the drinking water. After 3 months both groups were sub divided (n=4 per group) and treated for additional 3 months with Mn and/or M. officinalis in the drinking water. The first group (control) was treated with water and served as control; the second group (M. officinalis) was treated with M. officinalis (100 mg/kg/day); the third group was treated with Mn (100 mg/kg/day); the fourth group (Mn+M. officinalis) was treated with both Mn and M. officinalis (100 mg/kg/day each). Mn-treated mice showed a significant increase in thiobarbituric acid reactive species (TBARS) levels (a marker of oxidative stress) in both the hippocampus and striatum. These changes were accompanied by a decrease in total thiol content in the hippocampus and a significant increase in antioxidant enzyme activity (superoxide dismutase and catalase) in the hippocampus, striatum, cortex and cerebellum. Co-treatment with M. officinalis aqueous extract in Mn-treated mice significantly inhibited the antioxidant enzyme activities and attenuated the oxidative damage (TBARS and decreased total thiol levels). These results establish that M. officinalis aqueous extract possesses potent antioxidative properties, validating its efficacy in attenuating Mn-induced oxidative stress in the mouse brain.

TRP channels in neurogastroenterology: opportunities for therapeutic intervention

The members of the superfamily of transient receptor potential (TRP) cation channels are involved in a plethora of cellular functions. During the last decade, a vast amount of evidence is accumulating that attributes an important role to these cation channels in different regulatory aspects of the alimentary tract. In this review we discuss the expression patterns and roles of TRP channels in the regulation of gastrointestinal motility, enteric nervous system signalling and visceral sensation, and provide our perspectives on pharmacological targeting of TRPs as a strategy to treat various gastrointestinal disorders. We found that the current knowledge about the role of some members of the TRP superfamily in neurogastroenterology is rather limited, whereas the function of other TRP channels, especially of those implicated in smooth muscle cell contractility (TRPC4, TRPC6), visceral sensitivity and hypersensitivity (TRPV1, TRPV4, TRPA1), tends to be well established. Compared with expression data, mechanistic information about TRP channels in intestinal pacemaking (TRPC4, TRPC6, TRPM7), enteric nervous system signalling (TRPCs) and enteroendocrine cells (TRPM5) is lacking. It is clear that several different TRP channels play important roles in the cellular apparatus that controls gastrointestinal function. They are involved in the regulation of gastrointestinal motility and absorption, visceral sensation and visceral hypersensitivity. TRP channels can be considered as interesting targets to tackle digestive diseases, motility disorders and visceral pain. At present, TRPV1 antagonists are under development for the treatment of heartburn and visceral hypersensitivity, but interference with other TRP channels is also tempting. However, their role in gastrointestinal pathophysiology first needs to be further elucidated.

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

There is growing evidence that STW 5 (Iberogast), fixed combination of hydroethanolic herbal extracts), besides being effective in functional dyspepsia, also improves symptoms in irritable bowel syndrome (IBS). Clinical data indicate that modulation of mucosal secretion is a promising approach to treat intestinal disorders associated with IBS. We therefore explored the effect of STW 5 on secretion in the human intestine and the mechanisms by which it acts. The Ussing chamber technique was used to measure mucosal secretion in human intestinal mucosa/submucosa preparations and in human epithelial cell line T84. In addition, we recorded STW 5 effects on human enteric neurons with voltage sensitive dye imaging. In human tissue and T84 cells STW 5 induced a dose-dependent increase in ion secretion that was significantly reduced by the Na-K-Cl cotransporter blocker bumetanide, the adenylate cyclase inhibitor MDL-12 330, the non-specific and selective cystic fibrosis transmembrane conductance regulator (CFTR) inhibitors glibenclamide and CFTR(inh)-172, respectively, and the blocker of calcium dependent Cl(-) channels (ClCa) SITS (4-acetamido-4-isothiocyanatostilbene-2,2-disulphonic acid). It was unaffected by amiloride, a blocker of epithelial Na(+) channels. In human tissue, the nerve blocker tetrodotoxin significantly suppressed the STW 5 response. STW 5 evoked an increased spike discharge in 51% of human submucous neurons. Results suggest that STW 5 is a secretogogue in the human intestine by direct epithelial actions and through activation of enteric neurons. The prosecretory effect is due to increased epithelial Cl(-) fluxes via CFTR and Ca-dependent ClCa channels. STW 5 may be a novel option to treat secretory disorders associated with IBS and constipation.

Mechanisms involved in the antinociception caused by ethanolic extract obtained from the leaves of Melissa officinalis (lemon balm) in mice

The present study examined the antinociceptive effect of the ethanolic extract from Melissa officinalis L. and of the rosmarinic acid in chemical behavioral models of nociception and investigates some of the mechanisms underlying this effect. The extract (3-1000 mg/kg), given orally (p.o.) 1 h prior to testing, produced dose-dependent inhibition of acetic acid-induced visceral pain, with ID50 value of 241.9 mg/kg. In the formalin test, the extract (30-1000 mg/kg, p.o.) also caused significant inhibition of both, the early (neurogenic pain) and the late (inflammatory pain), phases of formalin-induced licking. The extract (10-1000 mg/kg, p.o.) also caused significant and dose-dependent inhibition of glutamate-induced pain, with ID50 value of 198.5 mg/kg. Furthermore, the rosmarinic acid (0.3-3 mg/kg), given p.o. 1 h prior, produced dose-related inhibition of glutamate-induced pain, with ID50 value of 2.64 mg/kg. The antinociception caused by the extract (100 mg/kg, p.o.) in the glutamate test was significantly attenuated by intraperitoneal (i.p.) treatment of mice with atropine (1 mg/kg), mecamylamine (2 mg/kg) or l-arginine (40 mg/kg). In contrast, the extract (100 mg/kg, p.o.) antinociception was not affected by i.p. treatment with naloxone (1 mg/kg) or D-arginine (40 mg/kg). It was also not associated with non-specific effects, such as muscle relaxation or sedation. Collectively, the present results suggest that the extract produced dose-related antinociception in several models of chemical pain through mechanisms that involved cholinergic systems (i.e. through muscarinic and nicotinic acetylcholine receptors) and the L-arginine-nitric oxide pathway. In addition, the rosmarinic acid contained in this plant appears to contribute for the antinociceptive property of the extract. Moreover, the antinociceptive action demonstrated in the present study supports, at least partly, the ethnomedical uses of this plant.

Clinical effects of STW 5 (Iberogast) are not based on acceleration of gastric emptying in patients with functional dyspepsia and gastroparesis

STW 5, a herbal extract, is effective for the treatment of symptoms in patients with functional dyspepsia (FD). However, its mode of action is still unclear and a modulation of gastric motility is hypothesized. This multicentre, placebo-controlled double-blind study addressed the question of whether STW 5 accelerates gastric emptying in patients with FD and gastroparesis. One-hundred and three patients diagnosed with FD were randomly assigned to a treatment with either STW 5 or a liquid placebo for 28 days. The primary end point of the study was a change of a validated gastrointestinal symptom (GIS) score under treatment. Additionally, patients underwent a (13)C octanoic acid breath test for the assessment of the gastric half-emptying time (t(1/2)). Patients with prolonged t(1/2) were diagnosed with gastroparesis and requested to repeat the test at the end of treatment. A change of t(1/2) was defined a secondary study end point. t(1/2) was prolonged in 48.6% of patients in the STW 5 group and in 43.8% of the placebo group. During treatment, t(1/2) increased non-significantly in patients treated with STW 5 (+23 +/- 109 min; P = 0.51) and slightly accelerated among patients in the placebo arm (-26 +/- 51 min; P = 0.77) (P = 0.49). The improvement of the GIS (P = 0.08) and the proportion of patients with a treatment response (P = 0.03) were more pronounced in the STW 5 group. Our findings suggest that the clinical effects of STW 5 in patients with FD and gastroparesis are not directly mediated by an acceleration of gastric emptying. A clear-cut correlation with symptom improvement is still lacking.

Dyspepsia in childhood and adolescence: insights and treatment considerations

Functional dyspepsia (FD) is common in children, with as many as 80% of those being evaluated for chronic abdominal pain reporting symptoms of epigastric discomfort, nausea, or fullness. It is known that patients with persistent complaints have increased comorbidities such as depression and anxiety. The interaction with psychopathologic variables has been found to mediate the association between upper abdominal pain and gastric hypersensitivity. These observations suggest that abnormal central nervous system processing of gastric stimuli may be a relevant pathophysiologic mechanism in FD. Despite increased understanding, no specific therapy has emerged; however, recent nonpharmacological-based options such as hypnosis may be effective. Novel approaches, including dietary manipulation and use of nutraceuticals such as ginger and Iberogast (Medical Futures Inc., Ontario, Canada), may also be considered.

STW 5/Iberogast: Multi-Target-Wirkung bei funktioneller Dyspepsie und Reizdarmsyndrom

Functional gastro-intestinal diseases such as functional dyspepsia and irritable bowel syndrome are a therapeutic challenge, as they are not only characterized by a multitude of symptoms, some of them with severe consequences for affected patients, but are also caused by a multitude of factors. The clinical efficacy of the therapeutics STW 5/Iberogast in these diseases has been proven in a number of randomized prospective clinical studies. Several preclinical studies suggest that its efficacy could be due to its complex composition of nine standardized herbal extracts, which act differently on multiple sites. This principle, which is quite popular in clinical medicine, was introduced as a multi-target therapy for functional bowel disorders. Components of STW 5/Iberogast reduce gastro-intestinal hypersensitivity and act spasmolytic on spastic, tonicising on atonic gastro-intestinal muscle. In addition a stimulating effect on reduced mucus-secretion, an inhibitory effect on enhanced gastric acid secretion and an anti-inflammatory effect have been shown. These effects could explain the clinical efficacy of STW5/Iberogast in a large range of symptoms.

Effects of Iberogast on proximal gastric volume, antropyloroduodenal motility and gastric emptying in healthy men

OBJECTIVE

The herbal preparation Iberogast has been reported to improve upper abdominal symptoms in functional dyspepsia (FD) and to decrease fundic tone, increase antral contractility, and decrease afferent nerve sensitivity in experimental animals. The effects of Iberogast on the human gastrointestinal tract have not been evaluated.

METHODS

We investigated the effects of oral control and Iberogast, each administered as a single dose (1.1 mL), in a double-blind randomized fashion, on proximal gastric volume (part A), antropyloroduodenal motility (part B), and gastric emptying and intragastric distribution of a solid/liquid meal (part C) for 120 minutes, in nine (part A), 12 (part B), and eight (part C) healthy men.

RESULTS

Iberogast increased proximal gastric volume (max volume; control 104+/-12 mL, Iberogast 174+/-23 mL, P<0.05) (part A), increased the motility index of antral pressure waves in the first 60 minutes (P<0.05) without affecting pyloric or duodenal pressures (part B), and slightly increased the retention of liquid in the total stomach between 10 and 50 minutes (P<0.01), but had no effect on gastric emptying of solids or intragastric distribution (part C).

CONCLUSIONS

Iberogast affects gastric motility in humans, probably in a region-dependent manner. The stimulation of gastric relaxation and antral motility may contribute to the reported therapeutic efficacy of Iberogast in FD.

STW 5 (Iberogast) and its individual herbal components modulate intestinal electrophysiology of mice

STW 5 (Iberogast), a phytomedicine agent consisting of a fixed combination of nine individual plant extracts, is widely used in the treatment of dyspepsia and motility related disorders. Little if anything is known on the possible influence on electrophysiological properties of intestinal smooth muscle by which STW 5 causes its beneficial effects. The aim of the present study was to investigate whether herbal extracts influence electrophysiological parameters of large and small intestine. For this purpose intracellular recordings of smooth muscle cell (SMC) of the circular muscle layer of different parts of mouse intestine were performed using standard microelectrode techniques. The resting membrane potential (RMP), excitatory and inhibitory neurotransmission in proximal colon, the frequency and the amplitude of slow waves in small intestine were investigated. The RMP of SMC was -46.4+/-3.8 mV, n=11 in the colon and -59+/-1.3 mV, n=15 in small intestine. STW 5 significantly depolarized the RMP of colonic (16.6+/-2.2 mV, n=6, p<0.05) and jejunal (9.6+/-1.6 mV, n=7, p<0.05) SMC. This depolarizing effect can be mainly attributed to the constituents of chamomile flower, Angelica root and greater celandine herb. Following the electrical field stimulations (EFSs), junction potentials are influenced in a distinct manner. Excitatory junctions potentials (EJPs) of the colon were not significantly reduced (13.1+/-4.8 vs. 10.1+/-2.8 n.s., n=6) but fast (fIJP) and slow (sIJP) inhibitory junction potentials of the murine colon are reduced significantly by STW 5 (fIJP: 21.6+/-8.1 vs. 11.6+/-2.1 and sIJP: 12.1+/-3.3 vs. 6.1+/-1.3 n=6, p<0.05). The basal frequency of small intestinal slow waves was 39.5+/-1.4 min(-1) and the amplitude was 23.1+/-0.9 mV, n=15. STW 5 significantly reduced amplitude and frequency of the slow waves (11.7+/-0.8 mV; 33.5+/-3.4 min(-1), n=6, p<0.05). This effect on slow waves represents the summation of effects of the nine individual phytoextracts. Whereas Angelica root and chamomile flower completely blocked the slow wave activity, bitter candy tuft increased the frequency and amplitude, greater celandine herb reduced frequency and amplitude of the slow wave, peppermint leaf reduced frequency and left amplitude unchanged and liquorice root, caraway fruit and lemon balm leaf had no effects in basic electrophysiological properties of SMC. This study demonstrates that STW 5 causes changes in SMC RMP, excitatory and inhibitory neurotransmission and slow wave rhythmicity. These effects represent a summation effect of different constituents of this phytotherapeuticum and prove that STW 5 has characteristic effects on intestinal electrophysiology.

STW 5 (Iberogast) reduces afferent sensitivity in the rat small intestine

INTRODUCTION

A limited number of drugs are available for the treatment of functional dyspepsia and irritable bowel syndrome. The efficacy of STW 5 (Iberogast) was previously shown in clinical trials. Since visceral hypersensitivity seems to be the prime pathomechanism of functional gastro-intestinal disorders, the aim of this study was to explore whether STW 5 reduces intestinal afferent sensitivity in the upper gastrointestinal tract.

METHODS

Two groups of male Wistar rats were pretreated with either the herbal preparation STW 5 or its vehicle (30.8% ethanol). Then, after 2h, general anesthesia was induced by pentobarbitone (60 mg kg(-1)i.p.) and extracellular multi-unit afferent recordings were obtained from mesenteric afferents innervating the proximal jejunum. The intestinal afferent nerve response to increasing doses of 5-HT and bradykinin were quantified as well as afferent discharge following a ramp distension of the adjacent intestinal loop from 0 to 60 cm H(2)O.

RESULTS

Afferent discharge to 5-HT and bradykinin increased dose-dependently. Following the different doses of 5-HT, the peak in afferent nerve discharge was always reduced after pretreatment with STW 5 compared to controls with a response of 110+/-5 imp s(-1) after STW 5 and 128+/-3 in vehicle controls at the maximum dose (40 microg kg(-1); p<0.05; mean+/-SEM). For bradykinin, afferent responses were reduced following STW 5 at the 20 and 40 microg kg(-1) dose but not at 10 microg kg(-1) (40 microg kg(-1)176+/-7 imp s(-1) following STW 5 versus 200+/-6 imp s(-1) in controls; p<0.05). The ramp distension of the intestinal loop stimulated a rise in intestinal afferent nerve discharge that was always lower in the STW 5 pretreated group compared to vehicle controls with the exception of the discharge rate at the pressure level of 0 and 20 cm H(2)O (all other pressures up to 60 cm H(2)O p<0.05).

CONCLUSIONS

Sensitivity of intestinal afferents to mechanical and chemical stimuli is reduced following treatment with the herbal preparation STW 5. This mechanism may help to explain why STW 5 relieves dyspeptic and bowel symptoms in patients.

The active components and the pharmacological multi-target principle of STW 5 (Iberogast)

The therapeutic equivalence of the multi-herbal drug combination STW 5 (Iberogast) with two synthetic standard drugs can be explained by an additive or overadditive pharmacological synergism. A review of the different chemical constituents contained in this fixed combination of nine herbal drug extracts and their dominant mechanisms of action shows that they correlate very well with the clinically relevant overall pharmacological profile of the multi-herbal drug combination. This comprises modulatory effects on gastro-intestinal motility, anti-inflammatory action, inhibitory effects on gastric acid production and anti-oxidative and radical-inhibiting properties. As a multi-drug preparation with a multitude of therapeutic targets relevant in functional gastrointestinal diseases, its pharmacological profile of action in accordance with the multi-target principle.

Binding of STW 5 (Iberogast) and its components to intestinal 5-HT, muscarinic M3, and opioid receptors

Clinical studies with the fixed herbal combination product STW 5 (Iberogast) have indicated an efficacy comparable to metoclopramide (5-HT(3) antagonist) and cisapride (5-HT(4) agonist) in functional gastro-intestinal diseases like functional dyspepsia (FD) and irritable bowel syndrome (IBS). Since serotonin (5-HT(3) and 5-HT(4)) and muscarinic M(3) receptors are known to play a central role in the etiology of FD and IBS, the extracts contained in STW 5 and several of their phytochemical components were studied in vitro for binding affinities to these receptors of the intestine. STW 5 inhibited the binding of (3)H-GR113808 and (3)H-4-DAMP to 5-HT(4) and M(3) receptors, respectively, about 10 times more potently than the binding of (3)H-GR65630 to 5-HT(3) receptors. IC(50) values for STW 5 did correspond to extract dilutions of 1:1000 (M(3) binding) and 1:2000 (5-HT(4) binding). In addition, STW 5 also potently inhibited the binding to opioid receptors with an IC(50) value of 1:2000. Of the nine herbal extracts contained in STW 5, the fresh plant extract of bitter candy tuft (Iberis amara) selectively inhibited binding to M(3) receptors, while ethanolic extracts of celandine herb and chamomile flower were selective to 5-HT(4), and liquorice root to 5-HT(3) receptors. Binding affinities to human recombinant 5-HT(3), 5-HT(4) and M(3) receptors were qualitatively similar to those of the corresponding intestinal receptors. The benzylisoquinoline alkaloid berberine had significant inhibitory action on 5-HT(4) and M(3) binding, showing IC(50) values of 40 ng/ml (100 nM) and 200 ng/ml (500 nM), respectively, but is present in the extract of celandine herb only in traces, so that also for the celandine extract a cooperative effect of several phytochemical constituents can be assumed. These in vitro data indicate that 5-HT(4) (to a lesser degree 5-HT(3)), muscarinic M(3), and opioid receptors represent target sites for the treatment of FD and IBS with STW 5 (Iberogast).

Spasmolytic and tonic effect of Iberogast (STW 5) in intestinal smooth muscle

STW 5 (Iberogast) is a fixed combination of nine medicinal plant extracts effective in the treatment of functional dyspepsia and irritable bowel syndrome. The effects of STW 5, a combination of Iberis amara fresh plant extract, and other eight plant extracts as well as single extract components including extracts from Menthae piperitae folium, Matricariae flos and Liquiritiae radix, were assayed in guinea pig ileum with or without stimulation with acetylcholine or histamine, in order to find a possible effect on the contractility of intestinal smooth muscle. STW 5 decreased acetylcholine- and histamine-induced contraction of guinea pig ileum. This was also true for extracts of Menthae piperitae folium, Matricariae flos and L. radix. Extract from I. amara, however, showed no spasmolytic action; in contrary, it increased the basal resting tone and contraction of atonic ileal segments. This was also true when STW 5 was employed. A spasmolytic action of STW 5 could also be observed in duodenum, jejunum and colon. These data are the first to show not only the spasmolytic effects of STW 5 and its component extracts in intestinal muscle but also the tonicising effects of STW 5 through its component Iberis amara extract in relaxed intestinal muscle. Thus, pharmacological evidence suggests a dual-action principle and may explain, at least in part, the clinically observed therapeutic efficacy of STW 5 (Iberogast) in both hypotonic and spastic dysmotility symptoms of functional dyspepsia and irritable bowel syndrome.