The rodent model of impaired gastric motility induced by allyl isothiocyanate, a pungent ingredient of wasabi, to evaluate therapeutic agents for functional dyspepsia

Functional dyspepsia (FD) is thought to be mainly based on gastric motility dysfunction and chronic hypersensitivity, yet FD animal models has been reported a few. We studied to establish the mouse model of impaired gastric motility induced by a pungent ingredient of wasabi allyl isothiocyanate (AITC), which is reliable to evaluate prokinetic agents. Male ddY mice were used. Gastric motility was measured by 13C-acetic acid breath test in conscious mice. AITC (80 mM) was given 60 min before the measurement of motility. Prokinetic agents including itopride (30, 100 mg/kg), mosapride (0.1-1 mg/kg), neostigmine (30 μg/kg), acotiamide (10-100 mg/kg), and daikenchuto (100-1000 mg/kg) were given 40 min before the measurement. AITC impaired gastric motility without mucosal damages, which reverted 24 h after AITC treatment. The decreased motility induced by AITC was restored by prokinetic agents such as itopride, mosapride, neostigmine, and acotiamide. In separate experiment, daikenchuto recovered the decreased motility induced by AITC, although daikenchuto had no effect on motility in normal condition. In conclusion, it is considered that the AITC-induced impaired gastric motility mouse model is useful to develop new prokinetic agents for treatment of FD, and to re-evaluate traditional Japanese herbal medicines.

Siponimod: A Review in Secondary Progressive Multiple Sclerosis

Oral siponimod (Mayzent®), a next-generation, selective sphingosine 1-phosphate receptor (S1PR) 1 and 5 modulator, is approved in several countries for the treatment of secondary progressive multiple sclerosis (SPMS), with specific indications varying between individual countries. In the pivotal EXPAND trial (median duration double-blind treatment 18 months) in a broad spectrum of patients with SPMS, once-daily oral siponimod 2 mg (initial dose titration over 6 days) was significantly more effective than placebo in reducing clinical and MRI-defined outcomes of disease activity and disability progression, including 3-month confirmed disability progression on the Expanded Disability Status Scale (EDSS), and was generally well tolerated in the core phase of the study. These beneficial effects of siponimod appeared to be sustained during up to 5 years of treatment in the ongoing open-label extension phase of EXPAND. The safety profile of siponimod is similar to that of other agents in its class, including adverse events of special interest (i.e. those known to be associated with S1PR modulators). No new safety signals were identified during up to 5 years' treatment in the open-label extension phase. Albeit further long-term efficacy and safety data from the real-world setting are required to fully define its role, given the paucity of current treatment options and its convenient dosage regimen, siponimod represents an important emerging option for the treatment of adult patients with SPMS with active disease evidenced by relapses or imaging-features of inflammatory activity.

<i>In vitro</i> Callus Induction of Sipahutar Pineapple (<i>Ananas comosus</i> L.) from North Sumatra Indonesia

BACKGROUND AND OBJECTIVE

Sipahutar pineapple (Ananas comosus L.) is a indigenous of pineapple grown in Sipahutar district, North Sumatra, Indonesia. Propagation of Sipahutar pineapple that being done traditionally is less effective, because the number of seeds that produced is very limited and requires a long time. Propagation through in vitro culture is an alternative solution to solve this problem. It is necessary to add plant growth regulator (PGR) to stimulate callus formation in Sipahutar pineapple explants (Ananas comosus L.). Callus induction of pineapple from Sipahutar was carried out by PGR treatment on MS medium. The purpose of this study was to determine the effect MS medium treatment with added dichlorophenoxyacetic acid (2,4-D) and benzyl amino purin (BAP) PGR on Sipahutar pineapple callus formation (Ananas comosus L.) with light and dark treatment.

MATERIALS AND METHODS

This callus induction research used a completely randomized design (CRD) with 2 factors, the first factor was treatment 2,4-D (0, 1, 2) ppm. The second factor is BAP (0, 0.5, 1) ppm.

RESULTS

Nine combinations of treatments are obtained. Each combination of treatments is treated in both light and dark conditions. The parameters of this study were the percentage (%) of explants that formed callus, the time of callus formed, callus texture, callus biomass, callus surface height and callus surface area. Data were analyzed with two-way ANOVA, followed by Duncan Multiple Rate Test (DMRT).

CONCLUSION

The study showed that the interaction between 2,4-D and BAP significantly affected the time of callus formed but 2,4-D and BAP did not significantly affect callus biomass, callus surface height and callus surface area. All explants can form callus, except explants without the addition of 2,4-D and BAP. The callus formed on 10 days after induction (DAI) and 12 DAI with the treatment of light and dark. The color of the produced callus were white, yellowish white, greenish white, brown, brownish yellow, brownish white, brownish green, yellowish green and greenish white. The callus formed is generally compact textures, except for explants which by giving 1 ppm 2,4-D produce friable callus.

Developmental toxicity and alteration of gene expression in zebrafish embryo exposed to 6-benzylaminopurine

6-benzylaminopurine (6-BA) is widely used in agriculture and horticulture as plant growth regulator. Its excessive use may pose a potential risk to both environment and human health, which is causing great concern. This study was undertaken to assess the acute developmental toxicity of 6-BA to zebrafish embryos based on OECD protocols and mortality, hatching rate and malformation were investigated. Results showed that the 96 h-LC₅₀ and 96 h- EC₅₀ values were 63.29 mg/L and 41.86 mg/L, respectively. No mortality or teratogenic effects were found at concentrations lower than 10 mg/L 6-BA at concentrations higher than 50 mg/L significantly inhibited hatchability and embryo development, induced serious toxicity characterized by morphologic abnormalities (elongated pericardium, heart and yolk sac edema, spine curvature) and functional failure (slow spontaneous movement and heart rate, growth retardation, yolk sac absorption retention). Moreover, 6-BA-induced apoptosis was observed in embryos by the acridine orange staining and confirmed by the apoptotic-related genes, all of which p53 was significantly up-regulated at concentrations higher than 10 mg/L, bax at concentrations higher than 12.5 mg/L, while bcl2 was down-regulated at concentrations higher than 25 mg/L. As for genes of cardiac development, qPCR results demonstrated that nkx2.5, gata5, and amhc were significantly down-regulated at concentrations higher than 25 mg/L, vmhc and atp2a2a at concentration of 50 mg/L, in contrast, hand2 was up-regulated at concentration of 50 mg/L. Our data indicate that 6-BA induces a dose-dependent toxicity resulting in apoptosis through the involvement of p53-dependent pathways and hindering normal heart development in zebrafish embryos.

Efficacy and safety of siponimod for multiple sclerosis: Protocol for a systematic review and meta-analysis

BACKGROUND

Multiple sclerosis is the most common demyelinating disease of the central nervous system with serious social and economic burden. Siponimod is a sphingosine-1-phosphate receptor agonist, and clinical trials in the past decade have shown good prospects for the treatment of multiple sclerosis. But there is a lack of comprehensive understanding of the dose-effect relationship and safety in different subtypes of multiple sclerosis at present.

METHODS

We will perform a systematic review and meta-analysis of clinical randomized controlled trials to evaluate the efficacy and safety of siponimod in multiple sclerosis. We will search PubMed, EMBASE, Cochrane Library, Clinical Trials, Cochrane Central Register of Controlled Trials (CENTRAL) using a comprehensive strategy. The reference lists of the articles we select for inclusion will be checked to identify additional studies for potential inclusion. Two reviewers will review all literature independently. Upon inclusion of articles, another 2 reviewers will extract available data using a standardized form and assess the potential bias. Review Manager will be used to conduct data synthesis. There is no requirement of ethical approval and informed consent.

RESULT

This is the first systematic assessment of siponimod for the treatment of multiple sclerosis. We predict it will provide high-quality synthesis of existing evidence for the efficacy and safety of siponimod for multiple sclerosis and a relatively comprehensive reference for clinical practice and clinical trials about siponimod to be conducted.

CONCLUSION

The results of the systematic review and meta-analysis will provide updated evidence for the use of siponimod for multiple sclerosis.

REGISTRATION

The systematic review and meta-analysis is registered in the PROSPERO international prospective register of systematic review (PROSPERO#CRD42018112721).

Cell dedifferentiation and multiplication of Burdock (Arctium Lappa) as a medicinal plant

Arctium lappa L. (Burdock) is an important plant with various pharmacological effects. According to the importance of this plant, optimization of its tissue culture will lead to more investigation and application of it. The aim of this study was to develop protocols for callus induction and shoot regeneration of A.  lappa. In order to optimize of tissue culture in A. lappa, callus induction, indirect regeneration and direct regeneration were carried out in factorial experiment based on Completely Randomized Designs (CRDs). Hypocotyl and cotyledon were cultured on the Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of 2,4-Dichlorophenoxyacetic acid (2,4-D) and 6-Benzylaminopurine (BAP) for callus induction. In indirect regeneration experiment various levels of BAP and α-Naphthaleneacetic acid (NAA) and two types of explants (calli derived from cotyledon and hypocotyl) were investigated. In direct regeneration section, various levels of BAP plus 2 mg/l NAA and different explants (cotyledon, hypocotyl and bud) were compared. In both cotyledon and hypocotyl, the maximum callus induction was observed on a media containing 2 mg/l 2,4-D plus 1 mg/l BAP (100% and 76.19% respectively). The highest percentage of indirect regeneration (65%) was observed at 1 mg/l BAP plus 0.5 mg/l NAA on calli from hypocotyl. The highest percentage of direct regeneration (90.33) was observed in hypocotyl with a lateral bud explant on MS medium supplemented with 0.5 mg/l BAP plus 2 mg/l NAA. In this study, optimization of tissue culture protocol for A. lappa was carried out as a research technique, as well as technique for further exploitation of this plant.

Ranitidine Can Potentiate The Prokinetic Effect Of Itopride At Low Doses- An In Vitro Study

BACKGROUND

Gastroparesis and GERD occur concomitantly in 40 percent of the cases. Prokinetic drugs and acid blockers are employed as the main treatment modality. Ranitidine is an acid blocker with additional prokinetic activity and Itopride is a known prokinetic drug. This study was designed to observe the synergistic potentiating prokinetic effect of Ranitidine on itopride on isolated duodenum of rabbits.

METHODS

Ranitidine (10-5-10-3) and itopride (10-6-10-5) were added in increasing concentrations to isolated duodenum of rabbits and contractions were recorded on PowerLab Data acquisition unit AHK/214. Cumulative dose response curves were constructed. The potentiating prokinetic effect of Ranitidine on itopride was seen by using a fixed dose of ranitidine and cumulatively enhancing doses of itopride on iWorx.

RESULTS

Ranitidine and itopride produced a dose dependent reversible contraction of the isolated tissue of rabbits with ranitidine showing a max response of 0.124mV and itopride showing a maximum response of 0.131mV. Ranitidine was able to potentiate the prokinetic effect of itopride at low doses but at high dose the effect began to wane off.

CONCLUSIONS

Ranitidine and itopride produce a statistically significant synergistic potentiating prokinetic effect at low doses in vitro.

[Use of itopride in the symptoms of functional dyspepsia in Russia: results of a phase IV prospective open-label multicenter clinical trial]

AIM

To evaluate the efficacy and safety of itopride used to treat the symptoms of functional dyspepsia (FD) of the upper gastrointestinal tract.

SUBJECTS AND METHODS

A prospective, open-label, multicenter trial using as a control the placebo response obtained in the previous investigations enrolled 96 adult patients. The diagnosis of FD corresponded to its Rome II criteria. Patients received itopride (Ganaton) oral tablets (50 mg) 3 times daily for 8 weeks. When included into the trial, the patients were orally given itopride (ganaton) tablets (50 mg) thrice daily before meals for 8 weeks. The patients' status was evaluated during (at weeks 4 and 8) and after (at week 12) treatment. Treatment response was assessed using the Global Patient Assessment (GPA) and the Leeds Dyspepsia Questionnaire (LDQ). To evaluate the safety of itopride use, the investigators studied the frequency of adverse events and carried out laboratory tests (renal and liver function tests) and electrocardiography (ECG).

RESULTS

The GPA showed that 53.76, 85.71, and 82.22% of the patients achieved a therapeutic effect of itopride at weeks 4, 8, and 12, respectively. The proportion of the patients who achieved the therapeutic effect (86%) at week 8 was higher than the historical placebo controls in the previous studies--45% (86% vs 45%; X2 = 68.868, df = 3; p < 0.001). The mean LDQ score at week 8 was significantly lower than that at baseline (2.09 and 9.36 scores; p < 0.001); 6 nonserious adverse events occurred in 3 (3.12%) of the 96 patients. During the follow-up period, there was a mild adverse event that was related to the test drug (atrial extrasystole as evidenced by ECG) and resolved a few days later.

CONCLUSION

Itopride is an effective and well-tolerated drug in the treatment of functional dyspepsia in the Russian patients.

In vitro acetylcholinesterase activity of peptide derivatives isolated from two species of Leguminosae

CONTEXT

Cratylia mollis Martius ex Benth. and Cenostigma macrophyllum Tul. (Leguminosae) are both endemic Brazilian plants and they are used by the natives as medicinal plants, and the leaves of C. mollis are also employed as forage for cattle during the dry season of region.

OBJECTIVE

Isolation of the compounds responsible for the acetylcholinesterase (AChE) inhibition from the CHCl3 active extract.

MATERIALS AND METHODS

Two peptidic compounds were isolated by chromatographic techniques from the CHCl3 extract of the leaves of C. mollis and C. macrophyllum. They were identified by spectrometric data analysis (MS and NMR) and they were subjected to AChE inhibition employing Ellman's test.

RESULTS

The peptides were identified as N-benzoylphenylalaninoyl-phenlyalaninolacetate (aurentiamide acetate) (1) and N-benzoylphenylalaninyl-N-benzoylphenylalaninate (2). Both peptides 1 and 2 exhibit AChE inhibition, with IC50 values equal to 111.34 µM and 137.6 µM, respectively.

DISCUSSION AND CONCLUSION

Compound 1 (aurentiamide acetate) has rarely been isolated from the Leguminosae family, and N-benzoylphenylalaninyl-N-benzoylphenylalaninate (2) is a compound that has never previously been isolated from this family. Compound 1 is shown to be a potent inhibitor of AChE, with IC50 values similar to the physostigmine control (141.51 µM).

[Bibenzyl from Dendrobium inhibits angiogenesis and its underlying mechanism]

Bibenzyl is a type of active compounds abundant in Dendrobium. In the present study, we investigated the inhibitory effects of six bibenzyls isolated from Dendrobium species on vascular endothelial growth factor (VEGF)-induced tube formation in human umbilical vascular endothelial cells (HUVECs). All those bibenzyls inhibited VEGF-induced tube formation at 10 micromol x L(-1) except tristin, and of which moscatilin was found to have the strongest activity at the same concentration. The lowest effective concentration of moscatilin was 1 micromol x L(-1). Further results showed that moscatilin inhibited VEGF-induced capillary-like tube formation on HUVECs in a concentration-dependent manner. Western blotting results showed that moscatilin also inhibited VEGF-induced phosphorylation of VEGFR2 (Flk-1/KDR) and extracellular signal-regulated kinase 1/2 (ERK1/2). Further results showed that moscatilin inhibited VEGF-induced activation of c-Raf and MEK1/2, which are both upstream signals of ERK1/2. Taken together, results presented here demonstrated that moscatilin inhibited angiogenesis via blocking the activation of VEGFR2 (Flk-1/KDR) and c-Raf-MEK1/2-ERK1/2 signals.

[Comparative data of prokinetics in treatment of gastroesophageal reflux disease in patients with diabetes]

The purpose is to evaluate the effectiveness of itopride (IP) and domperidone (DP) in the treatment of patients with gastroesophageal reflux disease (GERD), in combination with diabetes mellitus (DM) type 1 and 2.

MATERIALS AND METHODS

40 patients were examined with GERD and type 1 diabetes and 50 patients with GERD and type 2 diabetes. Each group of patients with GERD, DM 1 and 2 has been divided into: the basic subgroup receiving IG 50 mg 3 tid and control--DP 10 mg tid. Patients were also administered omeprazole. Both subgroups were strictly randomized to key indicators, except for therapy. Baseline and after 2 and 4 weeks, all patients were examined to identify complaints, endoscopy and pH-metric changes, gastric motility was studied by electrogastroenterographic method (PEGEG).

RESULTS

In the subgroups of patients with GERD + DM 1 and GERD + DM 2, received treatment with IG complaints on heartburn, regurgitation, odynophagia relieved significantly earlier then in the subgroups treated with DP. After 4 weeks of therapy, decreasing in the number of gastroesophageal refluxes, number of patients with erosive esophagitis B level, and normalization of the motility of the stomach were significantly higher in the groups of GERD + DM 1 and GERD + DM 2 received treatment with IG when compared with the subgroup of PD. There were no side effects of prokinetics.

CONCLUSION

IG was more effective then DP in the treatment of GERD in patients with diabetes, and may be recommended for inclusion in the scheme of treatment of this comorbidity.

EP1 receptor within the ventrolateral periaqueductal grey controls thermonociception and rostral ventromedial medulla cell activity in healthy and neuropathic rat

The aim of this study was to investigate the expression of prostaglandin EP1 receptor within the ventrolateral periaqueductal grey (VL PAG). The role of VL PAG EP1 receptor in controlling thermonociception and rostral ventromedial medulla (RVM) activity in healthy and neuropathic rats was also examined. EP1 receptor was indeed found to be expressed within the VL PAG and co-localized with vesicular GABA transporter. Intra-VL PAG microinjection of ONO-DI-004, a selective EP1 receptor agonist, dose-dependently reduced tail flick latency as well as respectively increasing and decreasing the spontaneous activity of ON and OFF cells. Furthermore, it increased the ON cell burst and OFF cell pause. Intra-VL PAG prostaglandin E2 (PGE2) behaved similarly to ONO-DI-004. The effects of ONO-DI-004 and PGE2 were antagonized by intra-VL PAG L335677, a selective EP1 receptor antagonist. L335677 dose-dependently increased the tail flick latency and ongoing activity of the OFF cells, while reducing the ongoing ON cell activity. It also decreased the ON cell burst and OFF cell pause. In neuropathic rats using spare nerve injury (SNI) of the sciatic nerve model, EP1 receptor expression decreased in the VL PAG. However, ONO-DI-004 and L335677 were able to alter pain responses and ON and OFF cell activity, as they did in healthy animals. Collectively, these data show that within the VL PAG, EP1 receptor has a facilitatory effect on the nociceptive response and consistently affects RVM neuron activity. Thus, the blockade of EP1 receptor in the VL PAG leads to antinociception in neuropathic pain conditions, despite its down-regulation. The expression of EP1 receptor on GABAergic neurons is consistent with an EP1 receptor blockade-induced disinhibition of the antinociceptive descending pathway at VL PAG level.

Does postprandial itopride intake affect the rate of gastric emptying? A crossover study using the continuous real time 13C breath test (BreathID system)

BACKGROUND/AIMS

The aim of this study was to determine whether oral Itopride hydrochloride (itopride) intake might have any effect on the rate of gastric emptying, using a novel non-invasive technique for measuring the rate of gastric emptying, namely, the continuous real time 13C breath test (BreathID system: Exalenz Bioscience Ltd., Israel).

METHODOLOGY

Eight healthy male volunteers participated in this randomized, two-way crossover study. The subjects fasted overnight and were randomly assigned to receive 50mg itopride following a test meal (200 kcal per 200mL, containing 100mg 13C acetate), or the test meal alone. Under both conditions, gastric emptying was monitored for 4 hours after administration of the test meal by the 13C-acetic acid breath test performed continually using the BreathID system. Using Oridion Research Software (beta version), the time required for emptying of 50% of the labeled meal (T 1/2), the analog to the scintigraphy lag time for 10% emptying of the labeled meal (T lag), the gastric emptying coefficient (GEC), and the regression-estimated constants (beta and kappa) were calculated. The parameters measured under the two conditions were compared using the Wilcoxon's signed-rank test.

RESULTS

No significant differences in the calculated parameters, namely, the T 1/2, T lag, GEC, beta or kappa, were observed between the two test conditions, namely, administration of a test meal+itopride and administration of the test meal alone.

CONCLUSIONS

The present study revealed that postprandial itopride intake had no significant influence on the rate of gastric emptying. Recently, several studies have shown that itopride may be effective in the treatment of patients with functional dyspepsia. Our results suggest that the efficacy of itopride in patients with functional dyspepsia may be based on its effect of improving functions other than the rate of gastric emptying, such as the activities at neuronal sites, brain-gut correlation, visceral hypersensitivity, gastric accommodation and distension-induced adaptation.

Pharmacokinetics and bioequivalence study of a fixed dose combination of rabeprazole and itopride in healthy Indian volunteers

The aim of the present study was to compare the pharmacokinetics of rabeprazole (CAS 117976-89-3) and itopride (CAS 122898-67-3) after oral administration of a rabeprazole (20 mg)-itopride (150 mg) fixed dose combination (FDC) in healthy human volunteers. The bioequivalence of two formulations (test and reference) was determined in 12 healthy Indian male volunteers (age: 25.25 +/- 4.69 years; weight: 60.50 +/- 5.04 kg) in a randomized, single-dose, two-period, two-treatment crossover study. Both formulations were administered orally as a single dose, with the treatments separated by a washout period of 1 week. Rabeprazole and itopride plasma levels were determined by a validated HPLC method using UV detection. The formulations were compared using the pharmacokinetic parameters area under the plasma concentration-time curve (AUC(0-t)), area under the plasma concentration-time curve from zero to infinity (AUC(0-infinity)) and peak plasma concentration (Cmax). General linear model (GLM) procedures were used in which sources of variation were subject, treatment and period. The results indicated that there were no statistically significant differences (P > 0.05) between the logarithmically transformed AUC(0-infinity) and Cmax values between test and reference formulation. The 90% confidence interval for the ratio of the logarithmically transformed AUC(0-t), AUC(0-infinity) and Cmax were within the bioequivalence limits of 0.8-1.25 and the relative bioavailability of rabeprazole and itopride test and reference formulations was 98.24 and 93.65%, respectively.

Targeting of mannosylated liposome incorporated benzyl derivative of Penicillium nigricans derived compound MT81 to reticuloendothelial systems for the treatment of visceral leishmaniasis

The antileishmanial property of a Benzyl derivative of a new antibiotic MT81 (Bz2MT81), isolated and purified from a fungal strain of Penicillium nigricans NRRL 917 was tested in free, liposome intercalated and mannose coated liposome intercalated forms in vivo against visceral leishmaniasis in hamsters. Mannose grafted liposome intercalated Bz2MT81 eliminated intracellular amastigotes of Leishmania donovani within splenic macrophages more efficiently than the liposome intercalated Bz2MT81 or free Bz2MT81. At a dose equivalent to 7.5 microg/Kg body weight when injected subcutaneously (s.c) in mannose grafted liposome intercalated form for 15 days in an interval of three days, the splenic parasitic load decreased to the extent of 79.1% of the total parasite present in infected control animals. Whereas, an identical amount (7.5 mug/Kg body weight) of Bz2MT81 in free or liposome intercalated form was found less effective in controlling the parasite in spleen (in free Bz2MT81 form, suppression of parasitic load is 49.8% and in liposome intercalated form, it is 55.1%). Both mannosylated liposomes and Bz2MT81 were noted non-toxic to the host peritoneal macrophages. Histological examinations of spleen and liver, kidney function tests (SGPT, alkaline phosphatase, creatinine and urea in blood plasma) showed that the toxicity of Bz2MT81 was reduced up to normal level when mannose grafted liposomal Bz2MT81 were administered.

Effects of itopride hydrochloride and ranitidine in patients with functional dyspepsia: comparison between prokinetic and acid suppression therapies

BACKGROUND/AIMS

The effect of itopride hydrochloride or ranitidine on the health-related quality of life (HRQoL) of functional dyspepsia is not well known. Our aim was to assess the HRQoL before and after administration of itopride hydrochloride or ranitidine in patients with functional dyspepsia.

METHODOLOGY

A total of 18 functional dyspepsia patients (12 women, 6 men; mean age 52.5 y.o.) were enrolled. We determined the HRQoL using two different inquiry systems: the 36 item short form of the Medical Outcome Study Questionnaire (SF-36) and the Gastrointestinal Symptom Rating Scale (GSRS). The HRQoL was determined before administration of drug, and two, four, and eight weeks after administration of drug.

RESULTS

After administration of itopride hydrochloride, the SF-36 mental health scale and GSRS indigestion syndrome score and constipation syndrome score were significantly improved compared to before administration (p < 0.05). After the administration of ranitidine, the GSRS reflux syndrome score was significantly improved compared to before administration (p < 0.05).

CONCLUSIONS

Itopride hydrochloride would be useful for the treatment of dysmotility-type functional dyspepsia, whereas ranitidine would be beneficial for ulcer-type functional dyspepsia.

Effects of endocannabinoid neurotransmission modulators on brain stimulation reward

RATIONALE

The endogenous cannabinoid system is responsive to the neurobiological actions of Delta9-tetrahydrocannabinol (THC) and other cannabinoid ligands. While numerous studies have focused on the behavioral and pharmacological effects of THC and cannabinoid agonists in experimental animals, most recent work focuses on compounds that modulate endocannabinoid neurotransmission. However, the relevant studies concerning the ability of endocannabinoid modulators to modify reward processes in experimental animals remain rather scarce.

OBJECTIVES

The present study examined the effects of drugs modulating endocannabinoid neurotransmission on brain reward function using the rate-frequency curve shift paradigm of intracranial self-stimulation (ICSS).

METHODS

Animals were implanted with electrodes into the medial forebrain bundle (MFB). After brain stimulation reward thresholds stabilized, rats received intraperitoneal injections of the fatty acid amide hydrolase (FAAH) inhibitors phenylmethylsulfonyl fluoride (PMSF) (0, 15, 30, and 60 mg/kg) and URB-597 (0, 0.3, 1, and 3 mg/kg) and the selective anandamide reuptake inhibitor OMDM-2 (0, 3, 10, and 30 mg/kg).

RESULTS

The highest dose of URB-597 and OMDM-2 significantly increased the threshold frequency required for MFB ICSS, while PMSF increased the threshold frequency in all doses tested. The cannabinoid 1 (CB1) receptor antagonist SR141716A reversed the actions of URB-597 and OMDM-2, but not PMSF, without affecting reward thresholds by itself.

CONCLUSIONS

These results indicate that under the present experimental conditions endocannabinoid modulators do not exhibit reinforcing properties, but rather have inhibitory influence on reward processes. The anhedonic effects of URB-597 and OMDM-2, but not PMSF, observed at the highest doses in this study are probably mediated through direct CB1 receptor stimulation.

Two new benzylbenzoate glucosides from Curculigo orchioides

An extract from in vitro cultures of Curculigo orchioides grown as bulbils in shake flasks, afforded two new glucosides of substituted benzylbenzoate - curculigoside C (3) and curculigoside D (4) - together with two known compounds - curculigoside A (1) and curculigoside B (2). Their structures were elucidated on the basis of spectral evidence, in particular by using 2D NMR methods. Their vasoactive properties were assessed in isolated rat aortic rings.

Anticonvulsant and acute neurotoxic characteristics of nicotinic acid benzylamide: a preclinical study

The aim of this study was to evaluate time-course and dose-response relationships of nicotinic acid benzylamide (Nic-BZA) with regard to its anticonvulsant activity in the maximal electroshock (MES)-induced seizures and acute neurotoxic effects in terms of motor coordination impairment in the chimney test in mice. The experimental determination of both median effective dose (ED(50)) and median toxic dose (TD(50)) allowed for the calculation of protective index (PI) values characterizing a preclinical profile of Nic-BZA. Results indicated that Nic-BZA produced the time-dependent and clear-cut anticonvulsant activity in the MES test and its ED(50) values ranged between 35.7 and 84.0 mg/kg (after the ip administration of the agent at 5 and 60 min, respectively), and between 72.0 and 152.1 mg/kg (at 5 and 60 min, respectively, following the po administration of Nic-BZA). In the chimney test, the TD(50) values for Nic-BZA, after its ip administration ranged between 188.5 and 509.9 mg/kg, whereas following its po administration the TD(50) values for Nic-BZA were between 552 and 1222.1 mg/kg. The PI values for Nic-BZA, calculated at various times after its ip and po administrations (ranging between 3.56 and 17), revealed that the agent has a favorable profile, when considering its both anticonvulsant and acute neurotoxic effects in this preclinical study. Based on this study, one can conclude that Nic-BZA might occur advantageous as a potential antiepileptic drug for breaking seizure attacks in patients with epilepsy.

Guinea pig maximization tests with formaldehyde releasers

The guinea pig maximization test was used to evaluate the sensitizing potential of formaldehyde and 6 formaldehyde releasers (Forcide 78, Germall 115, Grotan BK, Grotan OX, KM 200 and Preventol D2). The tests were carried out in 2 laboratories (Copenhagen and Stockholm), and although we intended the procedures to be the same, discrepancies were observed, possibly due to the use of different animal strains, test concentrations and vehicles. The sensitizing potential was in general found to be stronger in Stockholm compared to Copenhagen: formaldehyde sensitized 50% of the guinea pigs in Copenhagen and 95% in Stockholm. For Grotan BK, the corresponding rates were 20% and 74%. Forcide 78, KM 200 and Preventol D2 sensitized 20% to 25% of the animals in Copenhagen, while Germall 115 and Grotan OX sensitized 60% to 70% of the animals in Stockholm.

Distribution of the UV filter 3-benzylidene camphor in rat following topical application

A straightforward analytical method for determination of 3-benzylidene camphor (3-BC) in rat adipose tissue, brain, liver, muscle, plasma and testis following topical application was developed and validated. Three exposure levels (60, 180 and 540 mg kg(-1) day(-1)) were tested for 65 days in male Sprague-Dawley rats (24 days postnatal). Sample preparation involving homogenization and n-heptane or methanol extraction of the tissue was applied before injection into the LC-ESI-MS-MS system. The response was linear from 2 to 100 microg l(-1) for the qualifier and the quantifier MRM transitions (R(2) (quantifier) > 0.994). Detection limit of the method corresponded to 0.005 microg g(-1) tissue and 12.5 microg l(-1) plasma, respectively. Recovery was determined for all tissues (adipose tissue: 40%; all other tissues: 80-100%) at three individual levels. 3-(4-Methyl benzylidene camphor) (4-MBC) was used throughout the study as internal standard. 3-Benzylidene camphor was detected in all tissues at all exposure levels at concentrations between 0.05 microg g(-1) (liver) and 36 microg g(-1) (adipose tissue) and in plasma at 16-89 microg l(-1). The method allowed for the quantification of 3-benzylidene camphor in all tested tissues following topical application. Furthermore, it was shown that 3-benzylidene camphor can be found in various tissues in the rat following topical application. These findings may suggest that following use of 3-benzylidene camphor containing sunscreen, similar disposition and distribution may occur in humans.

A placebo-controlled trial of itopride in functional dyspepsia

BACKGROUND

The treatment of patients with functional dyspepsia remains unsatisfactory. We assessed the efficacy of itopride, a dopamine D2 antagonist with anti-acetylcholinesterase [corrected] effects, in patients with functional dyspepsia.

METHODS

Patients with functional dyspepsia were randomly assigned to receive either itopride (50, 100, or 200 mg three times daily) or placebo. After eight weeks of treatment, three primary efficacy end points were analyzed: the change from baseline in the severity of symptoms of functional dyspepsia (as assessed by the Leeds Dyspepsia Questionnaire), patients' global assessment of efficacy (the proportion of patients without symptoms or with marked improvement), and the severity of pain or fullness as rated on a five-grade scale.

RESULTS

We randomly assigned 554 patients; 523 had outcome data and could be included in the analyses. After eight weeks, 41 percent of the patients receiving placebo were symptom-free or had marked improvement, as compared with 57 percent, 59 percent, and 64 percent receiving itopride at a dose of 50, 100, or 200 mg three times daily, respectively (P<0.05 for all comparisons between placebo and itopride). Although the symptom score improved significantly in all four groups, an overall analysis revealed that itopride was significantly superior to placebo, with the greatest symptom-score improvement in the 100- and 200-mg groups (-6.24 and -6.27, vs. -4.50 in the placebo group; P=0.05). Analysis of the combined end point of pain and fullness showed that itopride yielded a greater rate of response than placebo (73 percent vs. 63 percent, P=0.04).

CONCLUSIONS

Itopride significantly improves symptoms in patients with functional dyspepsia. (ClinicalTrials.gov number, NCT00272103.).

Block of peripheral nerve sodium channels selectively inhibits features of neuropathic pain in rats

Several sodium channel blockers are used clinically to treat neuropathic pain. However, many patients fail to achieve adequate pain relief from these highly brain-penetrant drugs because of dose-limiting central nervous system side effects. Here, we describe the functional properties of trans-N-{[2'-(aminosulfonyl)biphenyl-4-yl]methyl}-N-methyl-N'-[4-(trifluoromethoxy)benzyl]cyclopentane-1,2-dicarboxamide (CDA54), a peripherally acting sodium channel blocker. In whole-cell electrophysiological assays, CDA54 blocked the inactivated states of hNa(V)1.7 and hNa(V)1.8, two channels of the peripheral nervous system implicated in nociceptive transmission, with affinities of 0.25 and 0.18 microM, respectively. CDA54 displayed similar affinities for the tetrodotoxin-resistant Na+ current in small-diameter mouse dorsal root ganglion neurons. Peripheral nerve injury causes spontaneous electrical activity in normally silent sensory neurons. CDA54 inhibited these injury-induced spontaneous action potentials at concentrations 10-fold lower than those required to block normal A- and C-fiber conduction. Consistent with the selective inhibition of injury-induced firing, CDA54 (10 mg/kg p.o.) significantly reduced behavioral signs of neuropathic pain in two nerve injury models, whereas the same dose of CDA54 did not affect acute nociception or motor coordination. In anesthetized dogs, CDA54, at plasma concentrations of 6.7 microM, had no effect on cardiac electrophysiological parameters including conduction. Thus, the peripheral nerve sodium channel blocker CDA54 selectively inhibits sensory nerve signaling associated with neuropathic pain.

Effect of repeated systemic administration of selective inhibitors of endocannabinoid inactivation on rat brain endocannabinoid levels

Several selective inhibitors of endocannabinoid inactivation via either the fatty acid amide hydrolase (FAAH) or the putative endocannabinoid transporter have been developed so far. Here, we have studied the effect in rats of a subchronic intraperitoneal treatment with three recently developed selective inhibitors of endocannabinoid uptake (VDM-11, UCM-707 and OMDM-2) or with a selective FAAH inhibitor (N-arachidonoyl-serotonin, AA-5-HT), on the brain levels of anandamide and 2-arachidonoylglycerol (2-AG) measured by means of isotope dilution LC-MS 1, 5 and 12 h after the last treatment. OMDM-2 was the most efficacious compound at enhancing the levels of anandamide at all time points, with a maximal effect (1.9-fold enhancement) after 5h. This compound also enhanced 2-AG levels by approximately 1.3-fold, but only 5 and 12h from administration. VDM-11 slightly, albeit significantly, enhanced anandamide levels (1.3-fold) only at 1h from administration and 2-AG levels (1.3-fold) only after 5h. Finally, UCM-707 only affected 2-AG levels (by two-fold) at only 1h from administration. FAAH inhibition by AA-5-HT significantly enhanced the levels of both anandamide (between 1.3- and 1.5-fold, maximal effect after 1 h) and 2-AG (between 1.3- and 1.6-fold, maximal effect after 12 h) at all time points. Brains from rats treated with AA-5-HT did never exhibit enhanced levels of serotonin, thus pointing to the metabolic stability of this FAAH inhibitor. These data indicate that: (1) the pharmacological effects reported so far for the four compounds under study in animal models of diseases may be due to enhancement of both anandamide and 2-AG levels; (2) 2-AG seems to need a longer time after the last administration in order to be augmented; (3) OMDM-2 and AA-5-HT should be regarded as enhancers of endocannabinoid levels suitable for use in vivo.

Effect of itopride, a new prokinetic, in patients with mild GERD: A pilot study

AIM: Itopride is a newly developed prokinetic agent, which enhances gastric motility through both antidopaminergic and anti-acetylcholinesterasic actions. The importance of esophageal motor dysfunction in the pathogenesis of gastro-esophageal reflux disease (GERD) makes it interesting to examine the effect of itopride on esophageal acid exposure.

METHODS: The effect of itopride on esophageal acid reflux variables for 24 h was studied in 26 patients with GERD symptoms, pre-entry total acid exposure time (pH<4) of more than 5% and mild esophagitis (Savary-Miller grades I, II) proven by endoscopy. Ambulatory 24-h pH-metry and symptom assessment were performed after treatments with 150 or 300 mg itopride thrice a day (t.i. d.) for 30 d in random order, using an open label method. For evaluating the safety of itopride, blood biochemical laboratory test was performed and the serum prolactin level was also examined before and after treatment.

RESULTS: Total symptom score was significantly decreased after treatment in 150- or 300-mg group. Itopride 300 mg was significantly effective than 150 mg on decreasing the total per cent time with pH < 4, total time with pH < 4 and DeMeester score. No serious adverse effects were observed with administration of itopride in both groups.

CONCLUSION: Itopride 100 mg t.i.d. is effective on decreasing pathologic reflux in patient with GERD and therefore it has the potential to be effective in the treatment of this disease.

Randomised, double-blind, comparative study to evaluate the efficacy and safety of ganaton (itopride hydrochloride) and mosapride citrate in the management of functional dyspepsia

Prokinetic agents like itopride hydrochloride and mosapride citrate are commonly used in the management of functional dyspepsia. However, in a recently conducted international, multicentric study, efficacy of 3 different regimens of mosapride was shown to be comparable to placebo. The objective of this phase 4 randomised, double blind, prospective study was to compare the efficacy and safety of ganaton (itopride hydrochloride) and mosapride citrate in the management of functional dyspepsia among patients attending the gastroenterology outpatient department of a tertiary care hospital. Ganaton 50 mg or mosapride citrate 5 mg three times daily before meals for a period of 2 weeks was administered orally. Thirty functional dyspepsia patients in each group (total = 60) were randomised to receive itopride hydrochloride or mosapride citrate treatment for 2 weeks. In itopride versus mosapride groups, global efficacy as judged by patients was excellent in 17 versus 9 (p < 0.05) and poor in 0 versus 3 (p < 0.05). In itopride versus mosapride group global efficacy as judged by physician was excellent in 24 (80%) versus 15 (50%) and poor in 0 (0%) versus 3 (10%) patients respectively. The global efficacy was rated as excellent to good in significantly (p < 0.05) more number of patients in itopride (93.3%) group as compared to mosapride (63.33 %) group. None of the patients reported any adverse events with itopride treatment. In the mosapride group 5 patients (16.7%) reported adverse events. Two patients (6.7%) were withdrawn from mosapride treatment due to adverse events. The physician rated global tolerability ofitopride versus mosapride treatment as excellent in 23 (76.7%) versus 8 (26.7%) (p < 0.05) and poor in 0 (0%) versus 6 (20%) patients respectively. It may be concluded that ganaton (itopride hydrochloride) is superior in efficacy and safety over mosapride citrate in the management of functional dyspepsia.

Comparative evaluation of the efficacy and tolerability of itopride hydrochloride and domperidone in patients with non-ulcer dyspepsia

BACKGROUND

Prokinetic drugs are widely used for treatment of non-ulcer dyspepsia (NUD).

AIMS AND OBJECTIVES

To assess the efficacy and tolerability of a new prokinetic agent, itopride hydrochloride in patients of NUD and compare it with domperidone.

METHODS

Fifty-six patients who fulfilled the inclusion and exclusion criteria were enrolled in the study. Patients underwent upper gastrointestinal endoscopy to rule out organic pathology as a cause for their symptoms. The patient's symptoms were graded on a 4-point scale (0 to 3) at the beginning of treatment and at the end of Week-one and Week-two Patients were randomly allocated to receive either one tablet of itopride hydrochloride 50mg three times daily or one tablet of domperidone 10mg three times daily for two weeks. Pre-treatment and post-treatment hemogram, liver function and renal function tests, prolactin level and ECG were done in all patients. The response to therapy was evaluated by assessing the relief of symptoms at the end of two weeks on a 5-point scale. Statistical analysis was done using two-tailed paired t-test; Wilcoxon matched pairs ranks sum test, Mann-Whitney-U test and chi-square test as applicable.

RESULTS

Of the fifty-five patients enrolled in the study (age range of 18-60 yrs, median age of 35yrs), 26 were males and twenty nine were females. They had a median duration of symptoms for 4 weeks. Twenty-seven patients received itopride and 28 received domperidone. One patient did not follow up in the domperidone group, thus 54 patients were evaluable for analysis. Moderate to complete symptomatic relief was observed in 22 (81%) patients in the itopride group and 19 patients (70%) in the domperidone group (p > 0.05, NS). Both the drugs were well tolerated and neither caused prolongation of QT interval nor any abnormality in any serum biochemistry values.

CONCLUSION

Therapy with itopride resulted in good symptomatic relief, was safe, well tolerated and comparable in efficacy to domperidone in relieving the symptoms of NUD. By virtue of its efficacy and tolerability, it could be an ideal choice for providing symptomatic relief to patients suffering from non-ulcer dyspepsia.

PEG Prodrugs of 6-Mercaptopurine for Parenteral Administration Using Benzyl Elimination of Thiols

6-Mercaptopurine (6-MP) is an orally administered, water-insoluble purine analog that is effective against acute lymphatic leukemia. Oral absorption of 6-MP, however, is quite erratic, with only 16-50% of the administered dose reaching the blood. In this report, water-soluble parenterally administered poly(ethylene glycol) (PEG) prodrugs of 6-MP were synthesized using several chemical approaches that enabled the protection of the thiol group through a modification of the benzyl elimination (BE) system. In our earlier work on antimetabolites, it was found that branching of the PEG allowed greater loading of the active drug. This approach was also utilized within this work to give multiloaded systems. The resulting conjugates were stable in pH 7.4 PBS buffer as well as in rat plasma for extended periods. However, these conjugates did act as prodrugs in vivo and a number of PEG-6-MP constructs had significant (P < 0.05) activity in murine leukemia, as well as certain solid tumors, compared with unconjugated 6-MP in a solubilizing vehicle. The fact that some PEG-6-MP conjugates were stable during in vitro plasma dissociation assays, but demonstrated in vivo anticancer activity, suggests extravascular cleavage of the linking group. This work demonstrates that PEG conjugation is an effective means of solubilizing 6-MP for parenteral administration.

Defining the Molecular Requirements for the Selective Delivery of Polyamine Conjugates into Cells Containing Active Polyamine Transporters

Several N(1)-substituted polyamines containing various spacer units between nitrogen centers were synthesized as their respective HCl salts. The N(1)-substituents included benzyl, naphthalen-1-ylmethyl, anthracen-9-ylmethyl, and pyren-1-ylmethyl. The polyamine spacer units ranged from generic (4,4-triamine, 4,3-triamine, and diaminooctane) spacers to more exotic [2-(ethoxy)ethanoxy-containing diamine, hydroxylated 4,3-triamine, and cyclohexylene-containing triamine] spacers. Two control compounds were also evaluated: N-(anthracen-9-ylmethyl)-butylamine and N-(anthracen-9-ylmethyl)-butanediamine. Biological activities in L1210 (murine leukemia), alpha-difluoromethylornithine (DFMO)-treated L1210, and Chinese hamster ovary (CHO) and its polyamine transport-deficient mutant (CHO-MG) cell lines were investigated via IC(50) cytotoxicity determinations. K(i) values for spermidine uptake were also determined in L1210 cells. Of the series studied, the N(1)-benzyl-4,4-triamine system 6 had significantly higher IC(50) values (lower cytotoxicity) in the L1210, CHO, and CHO-MG cell lines. A cellular debenzylation process was observed in L1210 cells with 6 and generated "free" homospermidine. The size of the N(1)-arylmethyl substituent had direct bearing on the observed cytotoxicity in CHO-MG cells. The N(1)-naphthalenylmethyl, N(1)-anthracenylmethyl, and N(1)-pyrenylmethyl 4,4-triamines had similar toxicity (IC(50)s: approximately 0.5 microM) in CHO cells, which have an active polyamine transporter (PAT). However, this series had IC(50) values of >100 microM, 66.7 microM, and 15.5 microM, respectively, in CHO-MG cells, which are PAT-deficient. The observed lower cytotoxicity in the PAT-deficient CHO-MG cell line supported the premise that the conjugates use PAT for cellular entry. In general, moderate affinities for the polyamine transporter were observed for the N-arylmethyl 4,4-triamine series with their L1210 K(i) values all near 3 microM. In summary, the 4,4-triamine motif was shown to facilitate entry of polyamine conjugates into cells containing active polyamine transporters.

Hepatoprotective effect of myristicin from nutmeg (Myristica fragrans) on lipopolysaccharide/d-galactosamine-induced liver injury

To evaluate the hepatoprotective activity of spices, 21 different spices were fed to rats with liver damage caused by lipopolysaccharide (LPS) plus d-galactosamine (D-GalN). As assessed by plasma aminotranferase activities, nutmeg showed the most potent hepatoprotective activity. Bioassay-guided isolation of the active compound from nutmeg was carried out in mice by a single oral administration of the respective fractions. Myristicin, one of the major essential oils of nutmeg, was found to possess extraordinarily potent hepatoprotective activity. Myristicin markedly suppressed LPS/D-GalN-induced enhancement of serum TNF-alpha concentrations and hepatic DNA fragmentation in mice. These findings suggest that the hepatoprotective activity of myristicin might be, at least in part, due to the inhibition of TNF-alpha release from macrophages. However, further studies are needed to elucidate the hepatoprotective mechanism(s) of myristicin.

Indazole carboxylic acids in male contraception

Two new chemical entities, 1-(2,4-dichlorobenzyl)-indazole-3-carbohydrazide and 1-(2,4-dichlorobenzyl)-indazole-3-acrylic acid, were synthesized based on the core structure of lonidamine (1-(2,4-dichlorobenzyl)-indazole-3-carboxylic acid). These compounds apparently exert their effects in the testis by perturbing the Sertoli-germ cell adherens junctions causing germ cell loss from the seminiferous epithelium. Recently completed studies in the rat have demonstrated the efficacy, reversibility, and potential use of these two compounds as oral contraceptives for men. Neither compound affected the hypothalamus-pituitary-testicular axis, and both compounds were neither hepatotoxic nor nephrotoxic. These results suggest that these two compounds are safe for further development.

Two new male contraceptives exert their effects by depleting germ cells prematurely from the testis

The three currently available male contraceptive approaches are 1) the barrier method such as the condom, 2) hormonal methods by disrupting the pituitary-testicular axis so as to impair spermatogenesis, and 3) immunological methods by preparing vaccines against male-specific antigens. We hereby describe an alternative approach in which attachments of developing germ cells onto the seminiferous epithelium are disrupted, thereby inducing their premature release into the tubular lumen. This in turn leads to infertility. A panel of analogues based on the core structure of 1-(2,4-dichlorobenzyl)-indazole-3-carboxylic acid was synthesized. These compounds were subjected to an in vivo screening assay assessing their effects in inducing the expression of testin, a testicular marker whose expression correlates with the integrity of Sertoli-germ cell junctions. An induction of testin expression in the testis signifies a disruption of Sertoli-germ cell junctions that is followed by depletion of germ cells from the seminiferous epithelium. Two compounds, namely 1-(2,4-dichlorobenzyl)-indazole-3-carbohydrazide (AF-2364) and 1-(2,4-dichlorobenzyl)-indazole-3-acrylic acid (AF-2785), were identified that caused detachment of germ cells, in particular round and elongated spermatids, from the epithelium inducing their premature release into the tubular lumen as confirmed by histological analysis. Adult rats receiving several oral doses of either one of these compounds became infertile within 3-7 wk after the epididymal sperm reserve was exhausted. Depending on the dosing of the administered compound, rats became infertile for 4-14 wk before their fertility gradually bounced back, illustrating the reversibility and efficacy of these new compounds. Also, these compounds did not appear to impair the hypothalamus-pituitary-testicular axis because the serum levels of LH, FSH, and testosterone of the treated animals did not change significantly when compared to control rats. In addition, results of serum microchemistry illustrate that liver and kidney function was not affected in animals treated with both compounds.

The kappa agonist fedotozine relieves hypersensitivity to colonic distention in patients with irritable bowel syndrome

BACKGROUND & AIMS

Visceral hypersensitivity plays a major role in the pathophysiology of inflammatory bowel syndrome (IBS). Opioid kappa receptors on afferent nerves may modulate it and may be the target of new IBS treatments. The aim of this study was to evaluate the effects of fedotozine, a potent and selective kappa agonist, on responses to colonic distention and colonic compliance in patients with IBS.

METHODS

Fourteen patients with IBS (Rome criteria; 50 +/- 12 years; 6 men and 8 women) were included in a randomized double-blind, crossover trial comparing the effect of an intravenous infusion of 100 mg fedotozine or saline on sensory thresholds elicited by left colon phasic distention (4-mm Hg steps for 5 minutes) up to a sensation of abdominal pain. Colonic compliance was compared by the slope of the pressure-volume curves built on placebo and on fedotozine.

RESULTS

In the fedotozine group, thresholds of first perception (28.7 +/- 5.9 mm Hg) and pain (34.7 +/- 5.5 mm Hg) were significantly greater than with placebo (23.3 +/- 4.5 and 29.0 +/- 3.5 mm Hg, respectively; P = 0.0078). Colonic compliance was 9. 20 +/- 3.87 mL. mm Hg-1 with placebo and 8.73 +/- 3.18 mL. mm Hg-1 with fedotozine (not significant).

CONCLUSIONS

Fedotozine increases thresholds of perception of colonic distention in patients with IBS without modifying colonic compliance. Fedotozine seems capable of reversing visceral hypersensitivity observed in these patients and could have some beneficial action on their symptoms.

The contractile effect of fedotozine on guinea pig isolated intestinal cells is not mediated by kappa opioid receptors

The compound fedotozine, recently described as a peripheral kappa opioid receptor agonist, was tested on smooth muscle cells isolated from the longitudinal muscle layer of the guinea pig ileum, in comparison with the selective kappa receptor agonist, compound U-50488. Fedotozine (1 nmol/l-1 micromol/l) caused a concentration-dependent contraction of intestinal cells, with a maximum decrease in cell length not significantly different from that caused by acetylcholine. The kappa agonist U-50488 (0.1 pmol/l-100 nmol/l) was without effect. The contractile effect of fedotozine was not significantly modified by naloxone (0.1-1 micromol/l). These results indicate that fedotozine can have direct excitatory effects on intestinal smooth muscle cells from the guinea pig ileum not mediated by activation of kappa opioid receptors.

Differential effects of fedotozine compared to other kappa agonists on diuresis in rats

The aim of our study was to test the effect of fedotozine (0.1-30 mg/kg, s.c.), a novel kappa opioid agonist, on water diuresis in the conscious hydrated rat. Its effect was compared to that of morphine (2.5-10 mg/kg), a mu opioid agonist and to some of the recognized kappa agonists described in the literature: bremazocine (0.3-30 micrograms/kg), tifluadom (0.1-3 mg/kg), Cl 977 1-1000 micrograms/kg), (-)-cyclazocine (0.01-1 mg/kg), PD 117,302 (0.03-3 mg/kg), U-50,488h (0.25-10 mg/kg) and U-69,593 (0.3-3 mg/kg). The effect of fedotozine was also tested after intracerebroventricular administration (100 micrograms/kg) and compared to that of U-50,488h (10-30 micrograms) and dynorphins A(1-17), A(1-13) and B(1-13) (2.5-10 micrograms). All the reference kappa agonists administered by the s.c. route induced water diuresis, whereas morphine inhibited diuresis and electrolyte excretion. However, fedotozine (0.1-30 mg/kg s.c.) had no effect on diuresis, even after low doses of naloxone (0.1 mg/kg s.c.) or nor-BNI (10 mg/kg s.c.), and at 1 mg/kg had inconsistent effects on electrolyte elimination. When administered in the lateral ventricle of the brain, U-50,488h and dynorphin A(1-17) induced water diuresis, unlike fedotozine (100 micrograms), DYN A(1-13) and DYN B(1-13) that had no effect on urine output. Furthermore, fedotozine did not alter the diuretic effects of U-50,488h. These results suggest that fedotozine is an atypical kappa agonist, lacking activity on the kappa receptor subtypes regulating diuresis.

Efficacy of peripheral kappa agonist fedotozine versus placebo in treatment of irritable bowel syndrome. A multicenter dose-response study

The efficacy and safety of the peripheral kappa agonist fedotozine was evaluated in a double-blind, multicenter study involving 238 patients with the irritable bowel syndrome. After a two-week washout, patients were assigned to one of four groups to receive either placebo or fedotozine three times a day at doses of 3.5, 15, or 30 mg for six weeks. Patient assessment of mean symptom intensity indicated that the 30-mg dose of fedotozine was superior to placebo in relieving maximal daily abdominal pain (P = 0.01), mean daily pain (P = 0.007), and abdominal bloating (P = 0.02). Changes in bowel function and defecation disorders could not be evaluated reliably. According to the investigators, the highest dose of fedotozine markedly reduced overall disease severity (P = 0.003) and the pain component of the symptomatic profile (P = 0.009). Clinical and laboratory safety was very good. Fedotozine 30 mg three times a day therefore appears to be effective and safe in the treatment of the abdominal pain and bloating associated with IBS.

Effects of gavage versus dosed feed administration on the toxicokinetics of benzyl acetate in rats and mice

Effects of gavage versus dosed feed administration on the toxicokinetics of benzyl acetate were studied in male F344 rats and B6C3F1 mice. Benzyl acetate was rapidly hydrolysed to benzyl alcohol and then oxidized to benzoic acid. After gavage administration of benzyl acetate in corn oil at 500 mg/kg (rats) and 1000 mg/kg (mice), high benzoic acid plasma concentrations were observed. In contrast, much lower benzoic acid plasma concentrations were found after dosed feed administration at about 615 mg/kg/day for rats and about 850 mg/kg/day for mice. Results show that although the daily doses of benzyl acetate are comparable, bolus gavage administration effectively saturated the benzoic acid elimination pathway whereas dosed feed administration did not. In contrast, hippuric acid plasma concentrations were similar after both gavage and dosed feed administration due to the depletion of the glycine supply pool. Study results could explain the different toxicity and carcinogenicity responses of benzyl acetate observed in 2-yr chronic gavage and dosed feed studies.

Computer assisted recognition and quantitation of the effects of airborne chemicals acting at different areas of the respiratory tract in mice

The pattern and timing of a normal breath in unanesthetized mice was analyzed from measurement of inspiratory and expiratory airflows (VI and VE). Airflow was measured via a differential pressure transducer, attached to a pneumotachograph, which itself was attached to a body plethysmograph into which a mouse was placed. The analog voltage from the differential pressure transducer was digitized and stored for analysis on a microcomputer. Criteria were developed to classify each breath as normal (N) or belonging into one of seven abnormal categories. The abnormal categories were arrived at by computer analysis, recognizing specific modifications of the normal pattern into patterns of: sensory irritation of the upper respiratory tract (S), airflow limitation within the conducting airways of the lungs (A) or pulmonary irritation at the alveolar level (P). Combinations of these effects, i.e., S+A, P+A, P+S and P+S+A were also recognized. Computer analysis of each breath also permitted quantitative evaluation of the degree of S, A or P abnormalities. To induce each type of effect we used inhalation exposures to 2-chlorobenzylchloride, carbamylcholine or propranolol. We propose that this approach will permit rapid evaluation of the possible effects of airborne chemicals at three levels of the respiratory tract, with the classification of the type of effect easily obtained in an objective way using well defined criteria, followed by quantitation of the degree of each effect.

Percutaneous absorption of benzyl acetate through rat skin in vitro. 2. Effect of vehicle and occlusion

The effect of vehicle and occlusion on the in vitro percutaneous absorption of [methylene-14C]-benzyl acetate (1.7-16.6 mg/cm2) has been studied in diffusion cells using full thickness skin from male Fischer 344 rats. Absorption of neat benzyl acetate through rat skin occluded with parafilm was 49.3 +/- 2.0% (mean +/- SD, n = 4) after 48 hr. When benzyl acetate in ethanol was applied to the skin and the skin was occluded with parafilm, the extent of absorption at 48 hr was not significantly different from that after neat application. However at 6 hr, as the ethanol content of the application mixture was increased, the absorption of benzyl acetate through occluded skin was enhanced proportionally (r = 0.999). When phenylethanol was used as a vehicle, the extent of the benzyl acetate absorption through occluded skin at 48 hr was enhanced (P less than 0.05) compared with that after application neat; with 50% (v/v) phenyl-ethanol, absorption at 48 hr was 56.3 +/- 4.9%. However, this enhanced absorption did not correlate with the proportion of phenylethanol in the application mixture. When dimethylsulphoxide was used as a vehicle, the extent of absorption of benzyl acetate through occluded skin at 48 hr was enhanced (P less than 0.05) compared with that after application neat (absorption was 59.3 +/- 3.7% of the applied dose when 50% (v/v) dimethylsulphoxide was used). As the dimethylsulphoxide content of the application mixture was increased, the absorption of benzyl acetate was enhanced proportionally. Occlusion of the skin surface with parafilm often significantly enhanced absorption (P less than 0.05), although the effect varied with time and vehicle. In general, the degree of any enhanced absorption caused by the use of a vehicle or occlusion of the skin was small, and, in most cases, would be unlikely to be toxicologically significant.

Stimulatory effect of N-[4-[2-(dimethylamino)-ethoxy] benzyl]-3,4-dimethoxybenzamide hydrochloride (HSR-803) on normal and delayed gastrointestinal propulsion

To estimate the effect of a new gastroprokinetic agent, N-[4-[2-(dimethylamino)ethoxy]benzyl]-3,4-dimethoxybenzamide hydrochloride (HSR-803), on non-ulcer dyspepsia, the influence of HSR-803 on gastrointestinal propulsion was assayed in dogs, rats and mice in comparison with some gastroprokinetic agents. HSR-803 (30 mg/kg, p.o.) significantly enhanced gastric emptying in dogs, and it significantly improved the delayed gastric emptying induced by dopamine (0.4 mg/kg, i.p.) and morphine (1 mg/kg, s.c.) in rats. Metoclopramide (30 mg/kg, p.o.) also significantly restored the dopamine-induced delay, but at a dose of 10 mg/kg, p.o., it enhanced the morphine-induced delay in gastric emptying in rats. HSR-803 (10-100 mg/kg, p.o.) increased small intestinal transit in mice in a dose-dependent manner, and the effect was abolished by atropine (0.3 mg/kg, i.p.). Metoclopramide also increased small intestinal transit, but domperidone and cisapride had no effect. In delayed small intestinal transit in mice, HSR-803 (10-100 mg/kg, p.o.) improved the morphine (0.3 mg/kg, s.c.)-induced delay in a dose-dependent manner. In conclusion, because of the promotion of normal and delayed gastrointestinal propulsion, HSR-803 seems to be a promising gastroprokinetic agent for the treatment of non-ulcer dyspepsia. The action of HSR-803 is likely to be exerted through cholinergic stimulation.

[Effects of inmecarb on alcohol intake and the state of hepatic cytochrome P-450 system during various stages of experimental alcoholism in rats]

The influence of the new anti-alcohol drug Inmecarb on the alcohol consumption as well as on activity of the liver cytochrome P-450 system was studied in rats during chronic alcohol intoxication in the free choice situation between water and 15% ethanol solution. It was shown that voluntary alcohol consumption of different duration (10 days to 8 months) does not change the activity of liver cytochrome P-450 system. Inmecarb treatment (40 mg/kg, i.p. twice a day) during 14 days resulted in decrease of alcohol consumption in rats. This effect was most pronounced in late stages of experimental alcoholism. Inmecarb decreases the cytochrome P-450 content and suppresses the activity of aniline hydroxylase in rats with different duration of voluntary alcohol intoxication, but most pronounced effect was observed during the late stages of experimental alcoholism.

[DBMP-85 was effective at diagnosis and LVP was effective at relapse in a case of acute mixed leukemia]

A 16 year-old boy was admitted to our hospital in April 1985, because of bilateral submandibular swellings. Hematological examination revealed Hb was 7.3 g/dl, WBC was 89,000/microliters (76% blast), and platelet was 154,000/microliters. His bone marrow was hypercellular and consisted with 91% blasts. Myeloperoxidase staining was positive for 38% of blasts. Auer rods were seen in some of blasts. Thus, the diagnosis was M1 according to FAB classification. Cytogenetic studies of 20 marrow cells were performed and all cells had 46, XY, -1, -7, 3q-, 7q-, 17q+, +2mar. Eighty five percent of blasts expressed HLA-DR and 43% of blasts expressed CD2 and CD13 simultaneously. Thus, this leukemia was considered as the hybrid type of acute mixed leukemia by surface marker analysis. DBMP-85 regimen, the chemotherapy for AML, was started after admission and complete remission (CR) was attained in June 1985. After 4 courses of post remission chemotherapy, he discharged in December 1985 and was followed at our outpatient clinic without chemotherapy. His disease was relapsed in June 1986, and the combination chemotherapy with mitoxantrone, etoposide and Ara-C was applied to him but failed to attain CR. Then, LVP protocol, the chemotherapy for ALL, was started and CR was achieved. The blasts at relapse had morphologically myeloid features, and expressed HLA-DR, CD2 and CD13 as well as at diagnosis. Cytogenetic studies at relapse showed some karyotype except gaining 12p- anomaly. Therefore, same blasts were considered to emerge at relapse. Our case suggests that LVP therapy may be effective for AML expressing myeloid and lymphoid surface markers.

Age-related changes in the disposition of benzyl acetate. A model compound for glycine conjugation

The in vivo metabolism and excretion of benzyl acetate (BA), a model compound for glycine conjugation, was examined in male Fischer 344 rats and C57BL/6N mice. Rats aged 3-4, 9, and 25 months received a single oral dose of either 5 or 500 mg/kg 14C-BA, while male mice aged 2, 13, and 25 months received a single oral dose of 10 mg/kg 14C-BA. Urine and feces were collected for 96 hr. Biliary excretion and plasma elimination were also examined in male Fischer rats after iv administration of 5 mg/kg 14C-BA. In both young and old rats and mice, hippuric acid (HA) was the major urinary metabolite after oral dosing of BA. No significant age-related difference was observed in rats in the urinary elimination of BA-derived radioactivity or in the percentage of the total dose excreted as hippuric acid (approximately 95%). Twenty-five-month old rats excreted a significantly higher percentage of the total dose as benzyl mercapturic acid (approximately 2%) than did 3- to 4-month-old rats (approximately 1%) at the 5 mg dose. Benzyl mercapturic acid excretion in 3- to 4-month-old rats was also increased significantly at 500 mg/kg BA vs. 5 mg/kg BA. Fecal excretion of BA-derived radioactivity declined significantly in 25-month-old rats at both the 5 and 500 mg dose. This decrease was reflected by an age-related decline in biliary excretion and higher plasma levels of BA-derived radioactivity. Examination of plasma metabolites revealed a significantly higher level of HA and benzoyl glucuronide in 25-month rats.(ABSTRACT TRUNCATED AT 250 WORDS)