In vitro and in silico investigation of FDA-approved drugs to be repurposed against Alzheimer's disease.

Alzheimer's disease (AD), one of the main causes of dementia, is a neurodegenerative disorder. Cholinesterase inhibitors are used in the treatment of AD, but prolonged use of these drugs can lead to serious side effects. Drug repurposing is an approach that aims to reveal the effectiveness of drugs in different diseases beyond their clinical uses. In this work, we investigated in vitro and in silico inhibitory effects of 11 different drugs on cholinesterases. The results showed that trimebutine, theophylline, and levamisole had the highest acetylcholinesterase inhibitory actions among the tested drugs, and these drugs inhibited by 68.70 ± 0.46, 53.25 ± 3.40, and 44.03 ± 1.20%, respectively at 1000 µM. In addition, these drugs are bound to acetylcholinesterase via competitive manner. Molecular modeling predicted good fitness in acetylcholinesterase active site for these drugs and possible central nervous system action for trimebutine. All of these results demonstrated that trimebutine was determined to be the drug with the highest potential for use in AD.

Amelioration of the abnormal phenotype of a new L1 syndrome mouse mutation with L1 mimetics.

L1 syndrome is a rare developmental disorder characterized by hydrocephalus of varying severity, intellectual deficits, spasticity of the legs, and adducted thumbs. Therapy is limited to symptomatic relief. Numerous gene mutations in the L1 cell adhesion molecule (L1CAM, hereafter abbreviated L1) were identified in L1 syndrome patients, and those affecting the extracellular domain of this transmembrane type 1 glycoprotein show the most severe phenotypes. Previously analyzed rodent models of the L1 syndrome focused on L1-deficient animals or mouse mutants with abrogated cell surface expression of L1, making it difficult to test L1 function-triggering mimetic compounds with potential therapeutic value. To overcome this impasse, we generated a novel L1 syndrome mouse with a mutation of aspartic acid at position 201 in the extracellular part of L1 (p.D201N, hereafter termed L1-201) that displays a cell surface-exposed L1 accessible to the L1 mimetics. Behavioral assessment revealed an increased neurological deficit score and increased locomotor activity in male L1-201 mice carrying the mutation on the X-chromosome. Histological analyses of L1-201 mice showed features of the L1 syndrome, including enlarged ventricles and reduced size of the corpus callosum. Expression levels of L1-201 protein as well as extent of cell surface biotinylation and immunofluorescence labelling of cultured cerebellar neurons were normal. Importantly, treatment of these cultures with the L1 mimetic compounds duloxetine, crotamiton, and trimebutine rescued impaired cell migration and survival as well as neuritogenesis. Altogether, the novel L1 syndrome mouse model provides a first experimental proof-of-principle for the potential therapeutic value of L1 mimetic compounds.

Trimebutine suppresses Toll-like receptor 2/4/7/8/9 signaling pathways in macrophages.

Because of the critical roles of Toll-like receptors (TLRs) and receptor for advanced glycation end-products (RAGE) in the pathophysiology of various acute and chronic inflammatory diseases, continuous efforts have been made to discover novel therapeutic inhibitors of TLRs and RAGE to treat inflammatory disorders. A recent study by our group has demonstrated that trimebutine, a spasmolytic drug, suppresses the high mobility group box 1‒RAGE signaling that is associated with triggering proinflammatory signaling pathways in macrophages. Our present work showed that trimebutine suppresses interleukin-6 (IL-6) production in lipopolysaccharide (LPS, a stimulant of TLR4)-stimulated macrophages of RAGE-knockout mice. In addition, trimebutine suppresses the LPS-induced production of various proinflammatory cytokines and chemokines in mouse macrophage-like RAW264.7 cells. Importantly, trimebutine suppresses IL-6 production induced by TLR2-and TLR7/8/9 stimulants. Furthermore, trimebutine greatly reduces mortality in a mouse model of LPS-induced sepsis. Studies exploring the action mechanism of trimebutine revealed that it inhibits the LPS-induced activation of IL-1 receptor-associated kinase 1 (IRAK1), and the subsequent activations of extracellular signal-related kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and nuclear factor-κB (NF-κB). These findings suggest that trimebutine exerts anti-inflammatory effects on TLR signaling by downregulating IRAK1‒ERK1/2‒JNK pathway and NF-κB activity, thereby indicating the therapeutic potential of trimebutine in inflammatory diseases. Therefore, trimebutine can be a novel anti-inflammatory drug-repositioning candidate and may provide an important scaffold for designing more effective dual anti-inflammatory drugs that target TLR/RAGE signaling.

Trimebutine Maleate Monotherapy for Functional Dyspepsia: A Multicenter, Randomized, Double-Blind Placebo Controlled Prospective Trial.

Background and Objectives: Functional dyspepsia (FD) is one of the most common functional gastrointestinal disorders; it has a great impact on patient quality of life and is difficult to treat satisfactorily. This study evaluates the efficacy and safety of trimebutine maleate (TM) in patients with FD. Materials and Methods: Α multicenter, randomized, double-blind, placebo controlled, prospective study was conducted, including 211 patients with FD. Participants were randomized to receive TM 300 mg twice per day (BID, 108 patients) or placebo BID (103 patients) for 4 weeks. The Glasgow Dyspepsia Severity Score (GDSS) was used to evaluate the relief of dyspepsia symptoms. Moreover, as a pilot secondary endpoint, a substudy (eight participants on TM and eight on placebo) was conducted in to evaluate gastric emptying (GE), estimated using a 99mTc-Tin Colloid Semi Solid Meal Scintigraphy test. Results: Of the 211 patients enrolled, 185 (87.7%) (97 (52.4%) in the TM group and 88 (47.6%) in the placebo group) completed the study and were analyzed. The groups did not differ in their demographic and medical history data. Regarding symptom relief, being the primary endpoint, a statistically significant reduction in GDSS for the TM group was revealed between the first (2-week) and final (4-week) visit (p-value = 0.02). The 99 mTc-Tin Colloid Semi Solid Meal Scintigraphy testing showed that TM significantly accelerated GE obtained at 50 min (median emptying 75.5% in the TM group vs. 66.6% in the placebo group, p = 0.036). Adverse effects of low to moderate severity were reported in 12.3% of the patients on TM. Conclusion: TM monotherapy appears to be an effective and safe approach to treating FD, although the findings presented here warrant further confirmation.

Prokinetics for the treatment of functional dyspepsia: Bayesian network meta-analysis.

BACKGROUND: Controversies persist regarding the effect of prokinetics for the treatment of functional dyspepsia (FD). This study aimed to assess the comparative efficacy of prokinetic agents for the treatment of FD. METHODS: Randomized controlled trials (RCTs) of prokinetics for the treatment of FD were identified from core databases. Symptom response rates were extracted and analyzed using odds ratios (ORs). A Bayesian network meta-analysis was performed using the Markov chain Monte Carlo method in WinBUGS and NetMetaXL. RESULTS: In total, 25 RCTs, which included 4473 patients with FD who were treated with 6 different prokinetics or placebo, were identified and analyzed. Metoclopramide showed the best surface under the cumulative ranking curve (SUCRA) probability (92.5%), followed by trimebutine (74.5%) and mosapride (63.3%). However, the therapeutic efficacy of metoclopramide was not significantly different from that of trimebutine (OR:1.32, 95% credible interval: 0.27-6.06), mosapride (OR: 1.99, 95% credible interval: 0.87-4.72), or domperidone (OR: 2.04, 95% credible interval: 0.92-4.60). Metoclopramide showed better efficacy than itopride (OR: 2.79, 95% credible interval: 1.29-6.21) and acotiamide (OR: 3.07, 95% credible interval: 1.43-6.75). Domperidone (SUCRA probability 62.9%) showed better efficacy than itopride (OR: 1.37, 95% credible interval: 1.07-1.77) and acotiamide (OR: 1.51, 95% credible interval: 1.04-2.18). CONCLUSIONS: Metoclopramide, trimebutine, mosapride, and domperidone showed better efficacy for the treatment of FD than itopride or acotiamide. Considering the adverse events related to metoclopramide or domperidone, the short-term use of these agents or the alternative use of trimebutine or mosapride could be recommended for the symptomatic relief of FD.

Comparative efficacy and safety of trimebutine versus mebeverine in the treatment of irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a functional disorder characterized by chronic or recurrent abdominal pain or discomfort with bowel disturbances. This prospective, randomized clinical trial has been conducted on IBS patients, using trimebutine and Mebeverine in separate group in parallel design to compare the efficacy and safety of Trimebutine 100mg twice daily with mebeverine 135mg twice daily. Patients of 15 to 60 years old and both sexes were included from the out patient department (OPD) of gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU) from June 2010 to December 2011. A validated IBS-QOL instrument consisted of 34 questions used to assess improvement of quality of life before and after treatment. A total of 140 patients were enrolled in this study. Eighteen patients dropped out. One hundred twenty two patients completed the trial. In this study at the end of 6 weeks therapy, improvement of symptoms was statistically significant. However, differences of improvement between the two groups in relieving various symptoms were not statistically significant. Mean QOL score before treatment was 103 in Trimebutine group and 106 in Mebeverine group. After 6 weeks of treatment mean QOL score was 82 in Trimebutine group and 95 in Mebeverine group indicating improvement in both groups was statistically significant. The difference between the two groups was also significant. No worsening of symptoms and no side effects of the therapeutic agents was observed in any patient during the trial.

[Effectiveness of treatment of pancreatic disorders in children (based on catamnesis)].

In the article results of supervision of the patients with chronic pancreatitis and dysfunction of Oddi's sphincter, pancreatic type, in polyclinic were presented. Among them: 50 children received in clinic therapeutic complex offered by us which included: phytoenzyme, spasmolytic and antioxidant. 50 children were treated in traditional way. Screening of functional condition of the pancreas revealed decreasing percentage of moderate exocrine insufficiency of pancreas (10% of incidences) in children with recurrent course of pancreatitis. In long-lasting course of pancreatitis in this group percentage of patients with moderate exocrine insufficiency was decreased due to 15%. At the same time, in patients with moderate and severe exocrine insufficiency (55 and 20% subsequently) which improves non complete efficiency of basic therapy.

Repositioning Trimebutine Maleate as a Cancer Treatment Targeting Ovarian Cancer Stem Cells.

The overall five-year survival rate for late-stage patients of ovarian cancer is below 29% due to disease recurrence and drug resistance. Cancer stem cells (CSCs) are known as a major contributor to drug resistance and recurrence. Accordingly, therapies targeting ovarian CSCs are needed to overcome the limitations of present treatments. This study evaluated the effect of trimebutine maleate (TM) targeting ovarian CSCs, using A2780-SP cells acquired by a sphere culture of A2780 epithelial ovarian cancer cells. TM is indicated as a gastrointestinal motility modulator and is known to as a peripheral opioid receptor agonist and a blocker for various channels. The GI50 of TM was approximately 0.4 µM in A2780-SP cells but over 100 µM in A2780 cells, demonstrating CSCs specific growth inhibition. TM induced G0/G1 arrest and increased the AV+/PI+ dead cell population in the A2780-SP samples. Furthermore, TM treatment significantly reduced tumor growth in A2780-SP xenograft mice. Voltage gated calcium channels (VGCC) and calcium-activated potassium channels (BKCa) were overexpressed on ovarian CSCs and targeted by TM; inhibition of both channels reduced A2780-SP cells viability. TM reduced stemness-related protein expression; this tendency was reproduced by the simultaneous inhibition of VGCC and BKCa compared to single channel inhibition. In addition, TM suppressed the Wnt/ß-catenin, Notch, and Hedgehog pathways which contribute to many CSCs characteristics. Specifically, further suppression of the Wnt/ß-catenin pathway by simultaneous inhibition of BKCa and VGCC is necessary for the effective and selective action of TM. Taken together, TM is a potential therapeutic drug for preventing ovarian cancer recurrence and drug resistance.

The trimebutine effect on Helicobacter pylori-related gastrointestinal tract and brain disorders: A hypothesis.

The localization of bacterial components and/or metabolites in the central nervous system may elicit neuroinflammation and/or neurodegeneration. Helicobacter pylori (a non-commensal symbiotic gastrointestinal pathogen) infection and its related metabolic syndrome have been implicated in the pathogenesis of gastrointestinal tract and central nervous system disorders, thus medications affecting the nervous system - gastrointestinal tract may shape the potential of Helicobacter pylori infection to trigger these pathologies. Helicobacter pylori associated metabolic syndrome, by impairing gut motility and promoting bacterial overgrowth and translocation, might lead to brain pathologies. Trimebutine maleate is a prokinetic drug that hastens gastric emptying, by inducing the release of gastrointestinal agents such as motilin and gastrin. Likewise, it appears to protect against inflammatory signal pathways, involved in inflammatory disorders including brain pathologies. Trimebutine maleate also acts as an antimicrobial agent and exerts opioid agonist effect. This study aimed to investigate a hypothesis regarding the recent advances in exploring the potential role of gastrointestinal tract microbiota dysbiosis-related metabolic syndrome and Helicobacter pylori in the pathogenesis of gastrointestinal tract and brain diseases. We hereby proposed a possible neuroprotective role for trimebutine maleate by altering the dynamics of the gut-brain axis interaction, thus suggesting an additional effect of trimebutine maleate on Helicobacter pylori eradication regimens against these pathologies.

A nitro-arginine derivative of trimebutine (NO2-Arg-Trim) attenuates pain induced by colorectal distension in conscious rats.

Irritable bowel syndrome (IBS) is characterized by dysfunction of the afferent pathways that may lead to visceral hypersensitivity. Trimebutine is a weak opioid receptor agonist used in the treatment of IBS. We report on the effects of a novel derivative in which trimebutine has been salified with nitro-arginine(NO2-Arg-Trim), in modulating nociception to colorectal distension (CRD) in intact and post-colitis rats,an animal model that mimics some features of IBS. Colorectal sensitivity and pain were assessed by measuring the abdominal withdrawal score (AWR) during CRD. Healthy rats were treated with vehicle,trimebutine (10 mg/kg i.p.) or NO2-Arg-Trim (4, 8 and 16 mg/kg i.p.). Post-colitis, allodynic rats were investigated 4 weeks after colitis induction. Treating healthy rats with NO2-Arg-Trim resulted in a dose-dependent attenuation of CRD-induced nociception and in an inhibition of CRD-induced overexpression of spinal cFOS mRNA. NO2-Arg-Trim-induced antinociception was reversed by the opioid receptor antagonist naloxone and by the NO synthase-cGMP pathway inhibitor methylene blue, while L-NAME had no effect.The antinociceptive effect of NO2-Arg-Trim was maintained in a rodent model of post-inflammatory allodynia. In this setting,NO2-Arg-Trim but not trimebutine, significantly down-regulated the spinal cFOS mRNA expression and increased blood concentrations of NO2 +NO3. Moreover, the expression of several genes involved in inflammation and pain, as IL-1beta, TNFalpha, COX2 and iNOS, was up-regulated in colonic tissue from post-colitis rats and NO2-Arg-Trim, but not trimebutine, effectively reversed this effect. In summary, these data suggest that NO2-Arg-Trim inhibits nociception induced by CRD in both healthy and post-colitis, allodynic rats. The NO2-arginine moiety interacts with the opioid agonist trimebutine to potentiate its analgesic activity. This study provides evidence that NO2-arginine derivative of trimebutine might have beneficial effect in the treatment of painful intestinal disorders.

Trimebutine: a state-of-the-art review.

Trimebutine maleate has been used extensively, since the late 1960's, for the treatment of functional gastrointestinal disorders, including irritable bowel syndrome (IBS). It is usually linked to the antispasmodic class of agents, but its properties make trimebutine an unmatched and multi-tasking compound. The efficacy on relieving abdominal pain has been demonstrated in various clinical studies with different protocols of treatment. The main effect was first believed to be merely due to its antispastic activity, but further evidences expanded the acknowledgement of a broader impact on the gastrointestinal tract. The actions of trimebutine are mediated via an agonist effect on peripheral mu, kappa and delta opiate receptors and a modulation of gastrointestinal peptides release. The final motor effects on the gut are summarized in an acceleration of the gastric emptying, an induction of premature phase III of the migrating motor complex in the small intestine and a modulation of the contractile activity of the colon. Moreover, it has been shown to have a role in regulating the visceral sensitivity. It has been observed that this drug is also a multiple-ion channel modulator in the gut. Its function at various levels, from motility to pain control, makes this drug unique and its spectrum of action can be exploited for the treatment of both hypermotility and hypomotility disorders including irritable bowel syndrome and other functional gastrointestinal diseases. This article provides an overview of the current knowledge on the pharmacological mechanisms of trimebutine and its clinical applications in gastrointestinal disorders. Its biochemical properties and the complex mechanisms of action, along with a well-studied pharmacological safety, make this compound still actual and valuable.

[A randomized and case-control clinical study on trimebutine maleate in treating functional dyspepsia coexisting with diarrhea-dominant irritable bowel syndrome].

OBJECTIVE: To observe the efficacy and adverse drug reaction of trimebutine maleate in treating patients with functional dyspepsia (FD) coexisting with diarrhea dominant irritable bowel syndrome (IBS-D). METHODS: 129 patients were enrolled in this randomized, case-control and prospective study and divided into 3 groups. Group A was treated with trimebutine maleate and bacillus licheniformis, Group B with trimebutine maleate and Group C with bacillus licheniformis. The symptoms of the patients were described with grading score and efficacy of treatment assessed according to the changes of grading score of symptoms. RESULTS: There was a significant decrease in the scores of postprandial fullness (4.55 +/- 0.85, 1.26 +/- 0.52; 4.36 +/- 0.66, 1.48 +/- 0.61), early satiation (4.05 +/- 0.96, 1.01 +/- 0.51; 3.89 +/- 0.81, 1.25 +/- 0.76), abdominal pain (9.26 +/- 0.68, 0.68 +/- 0.43; 9.57 +/- 1.60, 0.76 +/- 0.54) and total symptom score (20.00 +/- 1.25, 3.06 +/- 0.91; 19.05 +/- 2.28, 3.89 +/- 2.12) before and after treatment in Group A and B (P < 0.05), but there was no such significance in Group C (P > 0.05). There was a significant decrease in diarrhea score before and after treatment in the 3 groups (A: 4.78 +/- 0.76, 0.65 +/- 0.53; B: 4.13 +/- 0.65, 1.25 +/- 0.62; C: 4.65 +/- 0.88, 1.45 +/- 0.70) (P < 0.05). After treatment for 4 weeks, there was significant difference in the scores of postprandial fullness, early satiation, abdominal pain and total symptom score as well as the effective rate of every symptom and total effective rate between Group A or B and Group C (P < 0.05). The ratio of cost and effect was 4.07, 1.19 and 6.65 in Group A, B and C respectively, the Group B being the best. The rate of adverse drug reaction was 22.9% and 23.7% in Group A and B, and the main adverse drug reactions were mild thirst and constipation. CONCLUSIONS: In treating patients with functional dyspepsia coexisting with diarrhea dominant irritable bowel syndrome, trimebutine maleate has the advantage of high efficacy, low cost and few adverse reactions.

Trimebutine, a small molecule mimetic agonist of adhesion molecule L1, contributes to functional recovery after spinal cord injury in mice.

Curing spinal cord injury (SCI) in mammals is a daunting task because of the lack of permissive mechanisms and strong inhibitory responses at and around the lesion. The neural cell adhesion molecule L1CAM (L1) has been shown to favor axonal regrowth and enhance neuronal survival and synaptic plasticity but delivery of full-length L1 or its extracellular domain could encounter difficulties in translation to therapy in humans. We have, therefore, identified several small organic compounds that bind to L1 and stimulate neuronal survival, neuronal migration and neurite outgrowth in an L1-dependent manner. Here, we assessed the functions of two L1 mimetics, trimebutine and honokiol, in regeneration following SCI in young adult mice. Using the Basso Mouse Scale (BMS) score, we found that ground locomotion in trimebutine-treated mice recovered better than honokiol-treated or vehicle-receiving mice. Enhanced hindlimb locomotor functions in the trimebutine group were observed at 6 weeks after SCI. Immunohistology of the spinal cords rostral and caudal to the lesion site showed reduced areas and intensities of glial fibrillary acidic protein immunoreactivity in both trimebutine and honokiol groups, whereas increased regrowth of axons was observed only in the trimebutine-treated group. Both L1- and L1 mimetic-mediated intracellular signaling cascades in the spinal cord lesion sites were activated by trimebutine and honokiol, with trimebutine being more effective than honokiol. These observations suggest that trimebutine and, to a lesser extent under the present experimental conditions, honokiol have a potential for therapy in regeneration of mammalian spinal cord injuries.

Nonmotor gastrointestinal disorders in older patients with Parkinson's disease: is there hope?

Despite the fact that nonmotor symptoms (NMS) like gastrointestinal (GI) complaints are frequently reported in Parkinson's disease (PD), no therapeutic guidelines are available. This study aimed to manage some lower GI-NMS in a group of patients with PD. A total of 40 patients (17 males, 23 females; mean age 76.05±2.09 years) were randomly selected for this study. Patients were confirmed to have PD (modified Hoehn-Yars scale: 2.075±0.4) who had undergone levodopa or dopamine agonist treatment. In the non-motor symptoms questionnaire (NMS-Quest), regarding GI complaints, the following were recorded: abdominal pain, bloating, and constipation of mild-to-moderate severity. Laboratory studies, abdominal ultrasound, and upper and lower digestive endoscopies were performed to rule out organic issues. All patients increased their water intake to 2 L/d and alimentary fiber to 20-25 g/d. Twenty patients received trimebutine 200 mg three times daily half an hour before meals. The other 20 patients received probiotics (60 mg per-tablet of two lactic bacteria: Lactobacillus acidophilus and Bifidobacterium infantis), 2×/d, 1 hour after meals for 3 months along with the reassessment of GI complaints. Our results demonstrated that there were significant statistical differences in all assessed symptoms in the first group: 1.55±0.51 vs 0.6±0.5 (P<0.0001) for abdominal pain; 1.6±0.5 vs 0.45±0.51 (P<0.0001) for bloating; and 1.5±0.51 vs 0.85±0.67 (P=0.0014) for constipation with incomplete defecation. The second group displayed statistical differences only for abdominal pain 1.45±0.51 vs 1.05±0.69 (P=0.00432) and bloating 1.4±0.5 vs 0.3±0.47 (P<0.0001). For constipation with incomplete defecation, there was a slight improvement. Thus, there was no significant statistical difference: 1.35±0.49 vs 1.15±0.49 (P=0.2040). In conclusion, lower GI-NMS are frequently present, isolated or associated with other autonomic issues, even before the diagnosis of PD. Treatment with probiotics could improve abdominal pain and bloating as much as with trimebutine, but less for constipation with incomplete evacuation, where trimebutine showed better results.

Effect of nor-trimebutine on neuronal activation induced by a noxious stimulus or an acute colonic inflammation in the rat.

Nor-trimebutine is the main metabolite of trimebutine that is used in the treatment of patients with irritable bowel syndrome. Nor-trimebutine has a blocking activity on sodium channels and a potent local anesthetic effect. These properties were used to investigate the effect of nor-trimebutine on spinal neuronal activation induced by models of noxious somato-visceral stimulus and acute colonic inflammation. Nor-trimebutine was administered in rats either subcutaneously 30 min before intraperitoneal administration of acetic acid or intracolonically 30 min before intracolonic infusion of trinitrobenzenesulfonic acid. Abdominal contractions were counted for 1 h as a marker of abdominal pain. c-fos expression was used as a marker of neuronal activation and revealed by immunohistochemistry 1h after intraperitoneal acetic acid injection and 2 h after colonic inflammation. Nor-trimebutine decreased Fos expression in the thoraco-lumbar (peritoneal irritation) and lumbo-sacral (colonic inflammation) spinal cord in laminae I, IIo V, VII and X. This effect was also observed in the sacral parasympathetic nucleus after colonic inflammation. Nor-trimebutine induced a significant decrease of abdominal contractions following intraperitoneal acetic acid injection. These data may explain the effectiveness of trimebutine in the therapy of abdominal pain in the irritable bowel syndrome.

Studies on papillary function and effect of prifinium bromide and other antispasmodics on motility of the papillary region (sphincter of Oddi) in humans.

We determined endoscopically the motility of the papillary region in humans, using a pressure sensor devised in our department. The subjects were 184 patients with various diseases. Prifinium bromide and four other antispasmodics were given to 60 of the 184 patients, and their effects were investigated. In 41 (85%) of the 48 patients with chronic gastritis, regular wave patterns were noted. In 35 (85%) of the 41 patients with diseases of the biliary tract and papillary region, in nine (82%) of the 11 patients with pancreatic diseases, and in six (67%) of the nine patients with liver diseases, irregular wave patterns were observed. It was postulated that a high incidence of papillary dysfunction accompanies biliary and pancreatic diseases. Additionally, it was concluded that prifinium bromide has as potent an effect on motility of the papillary region as does a massive dose (40 mg) of hyoscine N-butylbromide.

A three-part controlled study of trimebutine in the treatment of irritable colon syndrome.

Three controlled trials were carried out in patients with irritable bowel syndrome to assess the effectiveness of trimebutine in controlling the symptoms of abdominal distension, pain, flatulence, constipation, diarrhoea and dyspepsia. In the first two trials, it was shown that 200 mg trimebutine 3-times daily for 3 days produced rapid relief of symptoms and was significantly (p less than 0.001) more effective than placebo, but not significantly so when the dosage level was halved. In the third trial, the results showed that 200 mg trimebutine 3-times daily for 2 weeks was as effective as 100 mg mebeverine 4-times daily in relieving the major symptoms and in improving motility. No serious side-effects were reported with trimebutine at the dosage used.

Fenoverine: smooth muscle synchronizer for the management of gastro-intestinal conditions. II. A trimebutine-controlled, double-blind, crossover clinical evaluation.

A double-blind, crossover trial was carried out in 40 in-patients with gastro-intestinal spasmodic syndromes to compare the effectiveness and tolerance of fenoverine and trimebutine. Patients were allocated at random to receive either 100 mg fenoverine or 150 mg trimebutine 3-times daily for 20 days and were then crossed over, without a wash-out period, to the alternative medication for a further 20 days. After the first dose, pain severity was monitored over 4 hours and changes in intensity compared between groups. During the two 20-day periods, the proportion of patients in complete or almost complete remission was monitored at 10-day intervals, and the pooled data similarly compared. At the end of the 40-day trial period, patients stated their preference for one or other treatment, and the relevant data were processed by sequential analysis. Subjective signs of adverse effects were monitored by questioning every 10 days, and haematology and haematochemistry before and after each phase of the study. The results showed that fenoverine produced significantly greater pain relief after a single dose in comparison with trimebutine over the 4 hours of observation. Similarly, it gave significantly more favourable clinical results after both the 10th and 20th day of treatment. Finally, according to the patients' preference, fenoverine was significantly preferred (p less than 0.05) in comparison with trimebutine. Neither treatment was associated with the onset of signs of possible adverse reactions, either subjective or objective.

Beneficial effect of trimebutine and N-monodesmethyl trimebutine on trinitrobenzene sulfonic acid-induced colitis in rats.

The use of local anesthetics, such as lidocaine, has been proposed in the treatment of distal ulcerative colitis. Trimebutine maleate (TMB) displays a local anesthetic activity higher than that of lidocaine in rabbit corneal reflex. TMB and nor-TMB its main metabolite in human show similar affinity to that of bupivacaine toward sodium channel labeled by [3H]batrachotoxin and block sodium currents in sensory neurons from rat dorsal root ganglia. The aim of this study was to evaluate the effects of TMB and nor-TMB in comparison to lidocaine and bupivacaine in a rat model of acute colonic inflammation induced by trinitrobenzene sulfonic acid (TNBS). A single intracolonic instillation of TNBS (50 mg/kg dissolved in ethanol 30%) led to early plasma extravasation then macroscopic damage (hyperemia and necrosis), increased colonic weight and tissular MPO, a marker of neutrophilic infiltration. Local administration of TMB at dose of 3 to 60 mg/kg, 30 min before, 24 and 48 h after colitis induction, significantly reduced the severity of colitis. Nor-TMB (1, 3, 10, 30 mg/kg) as well as lidocaine (1, 3, 10 mg/kg) dose-dependently reduced colitis while bupivacaine at 10 mg/kg did not affect it significantly. In contrast systemic administration of TMB, nor-TMB and lidocaine at 10 mg/kg had no significant effect. Furthermore, local administration of TMB (30 mg/kg) and lidocaine (10 mg/kg) significantly reduced plasmatic extravasation. In conclusion, intracolonic treatment with TMB and nor-TMB improved acute experimental TNBS-induced colitis in rat and these effects could be explained by their local anesthetic activity.

Antinociceptive effect of (S)-N-desmethyl trimebutine against a mechanical stimulus in a rat model of peripheral neuropathy.

Trimebutine (2-dimethylamino-2-phenylbutyl 3,4,5-trimethoxybenzoate, hydrogen maleate) relieves abdominal pain in humans. In the present study, the antinociceptive action of systemic (S)-N-desmethyl trimebutine, a stereoisomer of N-monodesmethyl trimebutine, the main metabolite of trimebutine in humans, was studied in a rat model of neuropathic pain produced by chronic constriction injury to the sciatic nerve. Mechanical (vocalization threshold to hindpaw pressure) stimulus was used. Experiments were performed two weeks after surgery when the pain-related behaviour has fully developed. (S)-N-desmethyl trimebutine (1, 3, 10 mg/kg s.c.) produced dose-dependent antinociceptive effects on the nerve-injured and the contralateral hindpaw. The effect of the lowest dose (1 mg/kg s.c.) of (S)-N-desmethyl trimebutine on the nerve-injured paw was equal to that seen after a ten time stronger dose on the contralateral paw. The effect of (S)-N-desmethyl trimebutine (1 mg/kg) was not naloxone reversible. The results suggest that systemic (S)-N-desmethyl trimebutine may be useful in the treatment of some aspects of neuropathic pain.