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

The protective impact of adapted trimebutine maleate-loaded nanostructured lipid carriers for alleviating the severity of acute colitis

Nanoparticles for colon-drug delivery were designed and evaluated to solve many discrepancy issues such as high adverse effects of released drugs, insufficient drug amount at diseased areas, and unintentionally premature drug release to noninflamed GIT regions. Herein, the goal of this work was to convert trimebutine maleate (TMB) into nanostructured lipid carriers (NLC) in order to improve its protective effects in ulcerative colitis. NLC of TMB was prepared by the hot homogenization followed by ultra-sonication method. A full 4²-factorial design was used to estimate the produced TMB-NLC. The study design included the exploration of the impact of two independent variables namely lipid mix amount and ratio (glyceryl mono stearate and capryol 90), surfactant concentration (0.5, 1, 1.5, and 2%), on the particle size, polydispersity index, and the entrapment efficiency (EE%). The protective activity of F9 was examined through macroscopical scores, histopathological changes, immunohistochemical localization of tumor necrosis factor-α (TNF-α) and examination of oxidative stress such as reduced glutathione (GSH), superoxide dismutase (SOD), and malondialdehyde (MDA) against acetic acid-induced colitis in rats. Consistent with our expectations, the orally administered optimized formula (F9) alleviated the severity of colitis in acetic acid-induced rat model of colitis likely owing to the controlled release compared to free TMB. We aimed to develop TMB-loaded NLC for the treatment of acute colitis with the goal of providing a superior drug safety profile over long-term remission and maintenance therapy.

New Potentiometric Screen-printed Sensors for Determination of Trimebutine Drug in Tablets, Serum and Urine Samples

A new sensit4e and select4e modified screen printed electrodes (MSPEs) and carbon paste electrodes (MCPEs) were studied in order to determine trimbutine maleate (TM) in pure, tablets, urine, and serum samples. These sensors were embodied with multiwalled carbon nanotubes (MWCNTs) since it improved the quality of the sensors in presence of potassium tetrakis (p-chlorophenyl) borate (KTpClPB) ionophore. A good Nernstian response for the constructed sensors, at optimum paste composition, was exhibited for determination of TM in concentration range of 1.5 × 10^-7 - 1.0 × 10^-2 and 1.0 × 10^-7- 1.0 × 10^-2 mol L^-1 at 25 °C with detection limit of 1.5 × 10^-7 and 1.0 × 10^-7 mol L^-1 for MCPE and MSPE, respect4ely. It seemed that the potential of the electrodes was independent on pH in the range of 2.0-8.0, 2.0-8.5, 2.0-8.5, and 2.0-9.0 g4ing slope as 56.77 ± 1.11, 57.82 ± 0.54, 57.95 ± 0.37, and 58.99 ± 0.28 mV decade^-1 for electrodes 1, 2, 3 and 4, respect4ely. MCPEs and MSPEs gave response time about 8 and 6 s with long lifetime (more than 3 and 5 months), respect4ely. A high select4ity of sensors was observed for TM regarding to a large number of interfering species. The constructed sensors were successfully applied for determination of TM in pure form, its pharmaceutical preparations and biological fluids using standard addition, calibration, and potentiometric titration methods with high precision and accuracy. The results showed a good agreement between the proposed method and the HPLC official method.

Protective effects of glycyrrhizic acid by rectal treatment on a TNBS-induced rat colitis model

Objectives

The research compared rectal and oral treatments with glycyrrhizic acid for trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats.

Methods

Wistar rats were randomly divided into seven groups: one normal and six with colitis, including TNBS, glycyrrhizic acid (2, 10 and 50 mg/kg, rectally treated and 10 mg/kg, orally treated) and sulfasalazine (positive control, 225 mg/kg rectally treated) groups. Colitis was induced by colonic administration of TNBS in 30% ethanol.

Key findings

There were significant pathological changes in colon in TNBS-treated groups, and rectal glycyrrhizic acid significantly attenuated colitis. Myeloperoxidase, tumour necrosis factor-α and interleukin-1β of colon tissue or serum in the rectal glycyrrhizic acid groups were markedly reduced when compared with the TNBS group, and lower than in the orally treated glycyrrhizic acid group. It was further noted that, in vitro, glycyrrhizic acid (up to 100 µg/ml) inhibited interleukin-6 and elevated interleukin-10 production in lipopolysaccharide-activated macrophages, and significantly inhibited proliferation of spleen lymphocytes, suggesting the immunoregulatory function of glycyrrhizic acid.

Conclusions

Rectally administered glycyrrhizic acid has significant protective effects against TNBS-induced colitis in rats, and the rectal route may be a complementary treatment for inflammatory bowel disease.

Anti-inflammatory efficiency of levobupivacaine in an experimental colitis model

AIM: To investigate the efficiency of levobupivacaine in treating experimentally induced colitis in rats.

METHODS: Colitis was induced by trinitrobenzene sulfonic acid and ethanol in 30 rats under general anesthesia, and 10 rats were used as a sham group. Subsequent to induction of colitis, rats were divided into three groups; budesonide group received 0.1 mg/kg budesonide, levobupivacaine group received 10 mg/kg levobupivacaine and saline group received 1 mL saline solution via rectal route for 7 d. In the sham group, only routine rectal catheterization was performed without use of any material. At the end of 7 d, laparotomy and total colectomy were performed for histopathological examination in all rats and blood samples were drawn for measurement of tumor necrosis factor (TNF)-α and interleukin (IL)-6 following cardiac puncture. Macroscopic and microscopic evaluations of the specimens were performed by a pathologist blinded to group assignment of the rats.

RESULTS: Weight loss (P = 0.016) and macroscopic examination scores (P = 0.001) were significantly higher in saline group than others. Histopathological scoring was comparable between all colitis groups (P = 0.350). There was no significant difference in TNF-α levels and IL-6 levels (P = 0.150).

CONCLUSION: The significant improvement in macroscopic scores suggests that levobupivacaine may have topical anti-inflammatory effects in an experimental colitis model; however, this finding was not supported by microscopic findings.

Effectiveness of trimebutine maleate on modulating intestinal hypercontractility in a mouse model of postinfectious irritable bowel syndrome

Trimebutine maleate, which modulates the calcium and potassium channels, relieves abdominal pain in patients with irritable bowel syndrome. However, its effect on postinfectious irritable bowel syndrome is not clarified. The aim of this study was to investigate the effectiveness of trimebutine maleate on modulating colonic hypercontractility in a mouse model of postinfectious irritable bowel syndrome. Mice infected up to 8 weeks with T. spiralis underwent abdominal withdrawal reflex to colorectal distention to evaluate the visceral sensitivity at different time points. Tissues were examined for histopathology scores. Colonic longitudinal muscle strips were prepared in the organ bath under basal condition or to be stimulated by acetylcholine and potassium chloride, and consecutive concentrations of trimebutine maleate were added to the bath to record the strip responses. Significant inflammation was observed in the intestines of the mice infected 2 weeks, and it resolved in 8 weeks after infection. Visceral hyperalgesia and colonic muscle hypercontractility emerged after infection, and trimebutine maleate could effectively reduce the colonic hyperreactivity. Hypercontractility of the colonic muscle stimulated by acetylcholine and high K(+) could be inhibited by trimebutine maleate in solution with Ca(2+), but not in Ca(2+) free solution. Compared with 8-week postinfectious irritable bowel syndrome group, 2-week acute infected strips were much more sensitive to the stimulators and the drug trimebutine maleate. Trimebutine maleate was effective in reducing the colonic muscle hypercontractility of postinfectious irritable bowel syndrome mice. The findings may provide evidence for trimebutine maleate to treat postinfectious irritable bowel syndrome patients effectively.

Postresuscitation tissue neutrophil infiltration is time-dependent and organ-specific

BACKGROUND

Hemorrhagic shock with conventional resuscitation (CR) primes circulating neutrophils and activates vascular endothelium for increased systemic inflammation, superoxide release, and end-organ damage. Adjunctive direct peritoneal resuscitation (DPR) with intraperitoneal instillation of a clinical peritoneal dialysis solution decreases systemic inflammation and edema formation by enhancing tissue perfusion. The aim of this study is to determine the effect of adjunctive DPR on neutrophil and fluid sequestration.

METHODS

Anesthetized rats were hemorrhaged to 40% mean arterial pressure for 60 min. Animals were randomized for CR with the return of the shed blood plus two volumes of saline, or CR plus adjunctive DPR with 30 mL of intraperitoneal injection of a clinical peritoneal dialysis solution. Tissue myeloperoxidase (MPO) level, a marker of neutrophil sequestration, and total water content were assessed in the gut, lung, and liver in sham animals and at time-points 1, 2, 4, and 24 h postresuscitation.

RESULTS

Resuscitation from hemorrhagic shock increases MPO level in all tissues in a near-linear fashion during the first 4 h following resuscitation. This occurs irrespective of the resuscitation regimen used. Tissue MPO level returned to baseline at 24 h following resuscitation except in the liver where CR and not adjunctive DPR caused a significant rebound increase. Adjunctive DPR prevented the CR-mediated obligatory fluid sequestration in the gut and lung and maintained a relative normal tissue water in these organs compared with CR alone (n = 7, F = 10.1, P < 0.01).

CONCLUSION

Hemorrhagic shock and resuscitation produces time-dependent organ-specific trends of neutrophil sequestration as measured with tissue levels of myeloperoxidase, a marker of neutrophil infiltration. Modulation of the splanchnic blood flow by direct peritoneal resuscitation did not alter the time-dependent neutrophil infiltration in end-organs, suggesting a subordinate role of blood rheology in the hemorrhage-induced neutrophil sequestration. Vulnerable window for neutrophil-mediated tissue damage exists during the first 4 h following resuscitation from hemorrhagic shock in rats. Direct peritoneal resuscitation prevents the early obligatory fluid sequestration and promotes early fluid mobilization.

Pharmacokinetic and bioequivalence evaluation of two formulations of 100 mg trimebutine maleate (Recutin™ and Polybutin™) in healthy male volunteers using the LC–MS/MS method

BACKGROUND

Trimebutine maleate is a prokinetic agent that acts directly on the smooth muscle of the GI tract. A bioequivalence (BE) study of 2 oral formulations of 100 mg trimebutine maleate (TMB) was carried out in 24 healthy male Korean volunteers according to a crossover-randomized design.

METHODS

Subjects were given a single dose of 2 100 mg tablets of each formulation. The test and reference formulations were Recutin (Hutax Co., South Korea) and Polybutin (Samil Co., South Korea), respectively. Each set of tablets was administered with 240 ml of water to subjects after 10 h overnight fasting on 2 treatment days separated by a 1 week washout period. After dosing, serial blood samples were collected for a period of 36 h. Plasma was analyzed for the main metabolite of TMB, N-monodesmethyl trimebutine (nor-TMB), by a validated LC with MS/MS detection capacity for nor-TMB in the range 5-1500 ng/ml, with a lower limit of quantification (LLOQ) of 5 ng/ml. Several pharmacokinetic (PK) parameters (including AUC(t), AUC(infinity), C(max), T(max), T(1/2), and K(e)) were determined from the plasma concentrations of nor-TMB of both formulations. AUC(t), AUC(infinity), and C(max) were tested for BE after log-transformation of the data.

RESULTS

No significant difference was found based on ANOVA; 90% confidence intervals (98.98%112.03% for AUC(t); 98.60%-113.20% for AUC(infinity); 90.85%-107.87% for C(max)) for the test and reference were found within KFDA acceptance range of 80-125%.

CONCLUSIONS

Based on these statistical inferences, it was concluded that Recutin is bioequivalent to Polybutin and can be used interchangeably in a clinical setting.

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.