In vitro models for neuropathic pain phenotypic screening in brain therapeutics.

The discovery of brain therapeutics faces a significant challenge due to the low translatability of preclinical results into clinical success. To address this gap, several efforts have been made to obtain more translatable neuronal models for phenotypic screening. These models allow the selection of active compounds without predetermined knowledge of drug targets. In this review, we present an overview of various existing models within the field, examining their strengths and limitations, particularly in the context of neuropathic pain research. We illustrate the usefulness of these models through a comparative review in three crucial areas: i) the development of novel phenotypic screening strategies specifically for neuropathic pain, ii) the validation of the models for both primary and secondary screening assays, and iii) the use of the models in target deconvolution processes.

Burden of itch in ichthyosis: a multicentre study in 94 patients.

BACKGROUND: From clinical experience, we know that itch is a major concern for many ichthyosis patients. Nonetheless, no previous studies specifically addressed the issue of itch in ichthyosis. OBJECTIVE: The objective of this study was to specifically address the burden of itch and all its dimensions in ichthyosis patients. METHODS: Ninety-four ichthyosis patients from four different centres were recruited to participate in this cross-sectional, questionnaire-based study. All participants completed the Leuven Itch Scale, a multidimensional self-report instrument that quantifies the frequency, duration, severity, distress, consequences and surface area of itch. RESULTS: Participants included 18 keratinopathic types, 55 autosomal recessive congenital ichthyoses, 11 X-linked recessive ichthyoses (XLRIs), 6 Netherton's ichthyoses, 1 Sjögren-Larsson type, 1 Iocrin ichthyosis and 2 unknown subtypes. Itch occurred in 93% of all patients. In patients with itch, 63% reported that it was often or always present, although most itch episodes were short in duration. Itch, in all its dimensions, was worst in patients with Netherton syndrome. Patients with XLRI had in general a lower itch profile. About half of all ichthyosis patients reported to experience flares during a change in weather, in a hot environment or in stressful situations, whereas a cold environment led to itch in only 26% of patients. The most significant consequences of itching were lesions from scratching, difficulties in falling asleep, bad mood and loss of concentration. CONCLUSIONS: Itch is a major concern in patients with ichthyosis, with significant impact on daily life. Research on future treatments should therefore take itch into consideration and itch should be evaluated in clinical studies. Among the studied subgroups, Netherton patients experienced the most severe consequences.

Creation and pilot test results of the dermatology-specific proxy instrument: the Infants and Toddlers Dermatology Quality of Life.

BACKGROUND: Until now, there was no validated dermatology-specific health-related quality of life (HRQoL) instrument to be used in youngest patients. OBJECTIVE: To create dermatology-specific proxy instrument for HRQoL assessment in children from birth to 4 years. METHODS: International focus groups, item selection and pilot tests were utilized. In order to avoid the problem of cross-cultural inequivalence, focus group work and pilot tests were planned simultaneously in all national centres of the project. Comprehensibility, clarity, acceptance and internal consistency of new instrument were checked. RESULTS: The title 'Infants and Toddlers Dermatology Quality of Life' was chosen for our new instrument with the proposed acronym 'InToDermQoL'. Focus group work was completed in seven national centres (Croatia, Germany, Greece, Malta, Poland, Romania and Ukraine). A total of 170 families of children with different skin diseases were interviewed, and a pilot version of the instrument was created. Centres from France, Denmark and Spain have joined the project at this stage. Parents of 125 children with skin diseases filled in the pilot versions of the instrument. Good comprehensibility, clarity, acceptance and internal consistency of the InToDermQoL were confirmed. The pilot test results showed that the InToDermQoL questionnaire well differentiates severity-dependent differences. It was also checked and confirmed during the pilot test that no significant information was missed in the questionnaire. Three age-specific versions of the InToDermQoL questionnaire with 10, 12 and 15 items, respectively, were approved for field tests. CONCLUSION: The pilot test results showed that the InToDermQoL questionnaire has good comprehensibility, clarity, acceptance and internal consistency and well differentiates severity-dependent differences. Further validation of the InToDermQoL during international field test will be performed.

Blockade of sigma 1 receptors alleviates sensory signs of diabetic neuropathy in rats.

BACKGROUND: E-52862 (S1RA, 4-[2-[[5-methyl-1-(2-naphthalenyl)-1H-pyrazol-3-yl]oxy]ethyl]-morpholine), a novel selective sigma 1 receptor (σ1R) antagonist, has demonstrated efficacy in nociceptive and neuropathic pain models. Our aim was to test if σ1R blockade with E-52862 may modify the signs of neuropathy in Zucker diabetic fatty (ZDF) rats, a type 2 diabetes model. METHODS: Mechanical and thermal response thresholds were tested on 7-, 13-, 14- and 15-week-old ZDF rats treated with saline or with E-52862 acutely administered on week 13, followed by sub-chronic administration (14 days). Axonal peripheral activity (skin-saphenous nerve preparation) and isolated aorta or mesenteric bed reactivity were analysed in 15-week-old ZDF rats treated with saline or E-52862 and in LEAN rats. RESULTS: Zucker diabetic fatty rats showed significantly decreased thermal withdrawal latency and threshold to mechanical stimulation on week 13 compared to week 7 (prediabetes) and with LEAN animals; single-dose and sub-chronic E-52862 administration restored both parameters to those recorded on week 7. Regarding axonal peripheral activity, E-52862 treatment increased the mean mechanical threshold (77.3 ± 21 mN vs. 19.6 ± 1.5 mN, saline group) and reduced the response evoked by mechanical increasing stimulation (86.4 ± 36.5 vs. 352.8 ± 41.4 spikes) or by repeated mechanical supra-threshold steps (39.4 ± 1.4 vs. 83.5 ± 0.9). E-52862 treatment also restored contractile response to phenylephrine in aorta and mesenteric bed. CONCLUSIONS: E-52862 administration reverses neuropathic (behavioural and electrophysiological) and vascular signs in the ZDF rat. SIGNIFICANCE: Blockade of σ1R avoids the development of diabetic neuropathy in rats, and may represent a potentially useful therapeutic approach to peripheral neuropathies in diabetic patients. WHAT DOES THIS STUDY ADD?: This study presents evidences for the potential usefulness of sigma receptor blockade on diabetic neuropathy in rats. The methodology includes behavioural evidences, electrophysiological data and vascular-isolated models.

Effects of centrally acting analgesics on spinal segmental reflexes and wind-up.

BACKGROUND: The spinal cord is a prime site of action for analgesia. Here we characterize the effects of established analgesics on segmental spinal reflexes. The aim of the study was to look for the pattern of action or signature of analgesic effects on these reflexes. METHODS: We used a spinal cord in vitro preparation of neonate mice to record ventral root responses to dorsal root stimulation. Pregabalin, clonidine, morphine and duloxetine and an experimental sigma-1 receptor antagonist (S1RA) were applied to the preparation in a cumulative concentration protocol. Drug effects on the wind-up produced by repetitive stimulation of C-fibres and on responses to single A- and C-fibre intensity stimuli were analysed. RESULTS: All compounds produced a concentration-dependent inhibition of total spikes elicited by repetitive stimulation. Concentrations producing ∼50% reduction in this parameter were (in µM) clonidine (0.01), morphine (0.1), pregabalin (1), duloxetine (10) and S1RA (30). At these concentrations clonidine, pregabalin and S1RA had significant effects on the wind-up index and little depressant effects on responses to single stimuli. Morphine and duloxetine did not depress wind-up index and showed large effects on responses to single stimuli. None of the compounds had strong effects on the amplitude of the non-nociceptive monosynaptic reflex. CONCLUSIONS: morphine and duloxetine had general depressant effects on spinal reflexes, whereas the effects of clonidine, pregabalin and S1RA appeared to be restricted to signals originated by strong repetitive activation of C-fibres. Results are discussed in the context of reported behavioural effects of the compounds studied.

Defense related phytohormones regulation in arbuscular mycorrhizal symbioses depends on the partner genotypes.

Arbuscular mycorrhizal (AM) symbioses are mutualistic associations between soil fungi and most vascular plants. Modulation of the hormonal and transcriptional profiles, including changes related to defense signalling, has been reported in many host plants during AM symbioses. These changes have been often related to the improved stress tolerance common in mycorrhizal plants. However, results on the alterations in phytohormones content and their role on the symbiosis are controversial. Here, an integrative analysis of the response of phylogenetically diverse plants (i.e., tomato, soybean, and maize) to two mycorrhizal fungi -Funneliformis mosseae and Rhizophagus irregularis- was performed. The analysis of the defense-related hormones salicylic acid, abscisic acid, and jasmonates, and the expression of marker genes of the pathways they regulate, revealed significant changes in the roots of mycorrhizal plants. These changes depended on both the plant and the AM fungus (AMF) involved. However, general trends can be identified: roots associated with the most effective colonizer R. irregularis showed fewer changes in these defense-related traits, while the colonization by F. mosseae led to significant modifications in all plants tested. The up-regulation of the jasmonate pathway by F. mosseae was found to be highly conserved among the different plant species, suggesting an important role of jasmonates during this AM interaction. Our study evidences a strong influence of the AMF genotype on the modulation of host defense signalling, and offers hints on the role of these changes in the symbiosis.

Pharmacological properties of S1RA, a new sigma-1 receptor antagonist that inhibits neuropathic pain and activity-induced spinal sensitization.

BACKGROUND AND PURPOSE: The sigma-1 (σ(1) ) receptor is a ligand-regulated molecular chaperone that has been involved in pain, but there is limited understanding of the actions associated with its pharmacological modulation. Indeed, the selectivity and pharmacological properties of σ(1) receptor ligands used as pharmacological tools are unclear and the demonstration that σ(1) receptor antagonists have efficacy in reversing central sensitization-related pain sensitivity is still missing. EXPERIMENTAL APPROACH: The pharmacological properties of a novel σ(1) receptor antagonist (S1RA) were first characterized. S1RA was then used to investigate the effect of pharmacological antagonism of σ(1) receptors on in vivo nociception in sensitizing conditions and on in vitro spinal cord sensitization in mice. Drug levels and autoradiographic, ex vivo binding for σ(1) receptor occupancy were measured to substantiate behavioural data. KEY RESULTS: Formalin-induced nociception (both phases), capsaicin-induced mechanical hypersensitivity and sciatic nerve injury-induced mechanical and thermal hypersensitivity were dose-dependently inhibited by systemic administration of S1RA. Occupancy of σ(1) receptors in the CNS was significantly correlated with the antinociceptive effects. No pharmacodynamic tolerance to the antiallodynic and antihyperalgesic effect developed following repeated administration of S1RA to nerve-injured mice. As a mechanistic correlate, electrophysiological recordings demonstrated that pharmacological antagonism of σ(1) receptors attenuated the wind-up responses in spinal cords sensitized by repetitive nociceptive stimulation. CONCLUSIONS AND IMPLICATIONS: These findings contribute to evidence identifying the σ(1) receptor as a modulator of activity-induced spinal sensitization and pain hypersensitivity, and suggest σ(1) receptor antagonists as potential novel treatments for neuropathic pain.

The intestinal anti-inflammatory effect of dersalazine sodium is related to a down-regulation in IL-17 production in experimental models of rodent colitis.

BACKGROUND AND PURPOSE: Dersalazine sodium (DS) is a new chemical entity formed by combining, through an azo bond, a potent platelet activating factor (PAF) antagonist (UR-12715) with 5-aminosalicylic acid (5-ASA). DS has been demonstrated to have anti-inflammatory effects on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats and recently in UC patients in phase II PoC. There is Increasing evidence that Th17 cells have an important role in the pathogenesis of inflammatory bowel disease (IBD). The aim of this study was to further characterize the anti-inflammatory effects of DS. EXPERIMENTAL APPROACH: Effect of DS (10 or 30 mg·kg(-1) b.i.d.) on TNBS-induced colitis in rats was studied after 2 and 7 days with special focus on inflammatory mediators. Additionally, its anti-inflammatory properties were analysed in two different models of dextran sodium sulphate (DSS)-induced colitis, BALB/c and C57BL/6 mice, the latter being dependent on IL-17. KEY RESULTS: DS, when administered for 7 days, showed intestinal anti-inflammatory effects in TNBS-induced colitis; these effects were observed both macroscopically and through the profile of inflammatory mediators (TNF, IL-1ß, IL-6 and IL-17). Although the 2 day treatment with DS did not induce intestinal anti-inflammatory effects, it was sufficient to reduce the enhanced IL-17 expression. DS showed beneficial effects on DSS-induced colitis in C57BL/6 mice and reduced colonic pro-inflammatory cytokines IL-1ß, IL-6 and IL-17. In contrast, it did not exert intestinal anti-inflammatory effects on DSS-induced colitis in BALB/c mice. CONCLUSIONS AND IMPLICATIONS: DS exerts intestinal anti-inflammatory activity in different rodent models of colitis through down-regulation of IL-17 expression.

Aspirina frente a anticoagulación en pacientes jóvenes con infarto cerebral secundario a síndrome antifosfolípido primario / Aspirin versus anticoagulation in young patients with cerebral infarction secondary to primary antiphospholipid syndrome

Introducción. El síndrome antifosfolípido primario (SAP) es un factor de riesgo independiente para infarto cerebral. Objetivo. Evaluar el riesgo de recurrencia, comparar los diferentes tratamientos y determinar los factores de riesgo asociados con recurrencia y complicaciones hemorrágicas en pacientes con infarto cerebral y SAP. Pacientes y métodos. Los datos prospectivamente recogidos de 92 pacientes menores de 45 años (71% mujeres; media de edad: 33,8 ± 8,9 años), con diagnósticos confirmados de infarto cerebral y SAP, tratados con anticoagulantes (n = 54) o aspirina (n = 38), se analizaron restrospectivamente. El seguimiento se realizó con evaluación neurológica cada 6 a 12 meses. Las medidas de pronóstico fueron: recurrencia de infarto cerebral, hemorragia intracerebral sintomática y sangrado menor. Resultados. Durante una mediana de seguimiento de 54 meses (rango: 12-240 meses), ocurrieron ocho (9%) infartos cerebrales recurrentes, sin diferencia entre el tratamiento con aspirina (n = 0) o anticoagulantes (n = 8). La tasa anual de recurrencia fue de 0,014 personas/año de seguimiento. La historia de trombosis previa y de abortos espontáneos fue más habitual en pacientes con recurrencia. Los pacientes tratados con aspirina provenían con mayor frecuencia de medio rural. Cuatro pacientes anticoagulados desarrollaron complicaciones hemorrágicas; dos, hemorragias menores, y dos, hematomas subdurales. El 76% de los casos evolucionó con buen pronóstico funcional (escala de Rankin modificada: 0-2). Conclusión. Con las limitaciones de un estudio no aleatorizado, nuestros datos sugieren que el riesgo de infarto cerebral arterial recurrente en pacientes jóvenes con infarto cerebral secundario a SAP es bajo, no homogéneo y probablemente independiente del tipo de antitrombótico utilizado (AU)

Introduction. The primary antiphospholipid syndrome (PAS) is an independent risk factor for cerebral infarction. Aim. To evaluate the risk of recurrence, to compare different treatments and determine the risk factors associated with recurrence and hemorrhagic complications in patients with cerebral infarction and PAS. Patients and methods. Prospectively collected data from 92 patients under 45 years (71% female, mean age 33.8 ± 8.9 years) with confirmed diagnoses of cerebral infarction and PAS, treated with anticoagulants (n = 54) or aspirin (n = 38) were retrospectively analyzed. Clinical follow-up was obtained by neurological examination every 6 to 12 months. Outcome measures were: recurrence of CI, symptomatic intracerebral hemorrhage, and minor bleeding. Results. During a median follow-up of 54 months (range: 12-240 months), there were 8 (9%) recurrent cerebral infarctions, with no difference between treatment with aspirin (n = 0) or anticoagulants (n = 8). The annual rate of recurrence was 0,014 person-years of follow-up. The history of previous thrombosis and spontaneous abortions were more frequent in patients with recurrence. Aspirin-treated patients more frequently came from rural areas. Four anticoagulated patients developed bleeding complications, two minor bleeding and two subdural hematomas. 76% of the cases evolved with good outcome (modified Rankin scale: 0-2). Conclusion. With the limitations of a nonrandomized study, our data suggest that the risk of recurrent arterial cerebral infarction in young patients with cerebral infarction secondary to PAS is low, probably non-uniform and independent of the type of antithrombotic (AU)

Dissociation between adipose tissue signals, behavior and the food-entrained oscillator.

Digestive and metabolic processes are entrained by restricted feeding (RFS) schedules and are thought to be potential elements of a food-entrained oscillator (FEO). Due to the close relationship of leptin with metabolic regulation and because leptin is a relevant communication signal of the individual's peripheral metabolic condition with the central nervous system, we explored whether leptin is an endogenous entraining signal from the periphery to a central element of an FEO. First we characterized in the rat the diurnal rhythm of serum leptin (in rats fed ad libitum (AL)), its adjustment to an RFS and the influence of fasting after RFS, or RFS followed by AL feeding and then total food deprivation (RF-AF) in the persistence of this fluctuating pattern. We also explored the response of free fatty acids and stomach weight under the same entraining conditions. We compared the metabolic response with the behavioral expression of drinking anticipatory activity (AA) under the same conditions. Finally, we tested the effect of daily i.c.v administration of leptin as a putative entraining signal for the generation of AA. Metabolic parameters responded to food entrainment by adjusting their phase to mealtime. However, leptin and free fatty acid rhythms persisted only for a few cycles in fasting conditions and readjusted to the light-darkness cycle after an RF-AF protocol. In contrast, behavioral food-entrained rhythms persisted after both fasting manipulations. Daily leptin i.c.v. administration did not produce AA, nor produce changes in the behavioral free-running rhythm. Stomach weight indicated an adaptive process allowing an extreme stomach distension followed by a slow emptying process, which suggests that the stomach may be playing a relevant role as a storage organ. In conclusion, metabolic signals here studied respond to feeding schedules by adjusting their phase to mealtime, but do only persist for a few cycles in fasting. Leptin does not produce AA and thus is not an entraining signal for FEO. The response of metabolic signals to feeding schedules depends on different mechanisms than the expression of AA.

Walnut-enriched diet increases the association of LDL from hypercholesterolemic men with human HepG2 cells.

In a randomized, cross-over feeding trial involving 10 men with polygenic hypercholesterolemia, a control, Mediterranean-type cholesterol-lowering diet, and a diet of similar composition in which walnuts replaced approximately 35% of energy from unsaturated fat, were given for 6 weeks each. Compared with the control diet, the walnut diet reduced serum total and LDL cholesterol by 4.2% (P = 0.176), and 6.0% (P = 0.087), respectively. No changes were observed in HDL cholesterol, triglycerides, and apolipoprotein A-I levels or in the relative proportion of protein, triglycerides, phospholipids, and cholesteryl esters in LDL particles. The apolipoprotein B level declined in parallel with LDL cholesterol (6.0% reduction). Whole LDL, particularly the triglyceride fraction, was enriched in polyunsaturated fatty acids from walnuts (linoleic and alpha-linolenic acids). In comparison with LDL obtained during the control diet, LDL obtained during the walnut diet showed a 50% increase in association rates to the LDL receptor in human hepatoma HepG2 cells. LDL uptake by HepG2 cells was correlated with alpha-linolenic acid content of the triglyceride plus cholesteryl ester fractions of LDL particles (r(2) = 0.42, P < 0.05). Changes in the quantity and quality of LDL lipid fatty acids after a walnut-enriched diet facilitate receptor-mediated LDL clearance and may contribute to the cholesterol-lowering effect of walnut consumption.

Novel azo derivatives as prodrugs of 5-aminosalicylic acid and amino derivatives with potent platelet activating factor antagonist activity.

This paper describes the synthesis of a series of azo compounds able to deliver 5-aminosalicylic acid (5-ASA) and a potent platelet activating factor (PAF) antagonist in a colon-specific manner for the purpose of treating ulcerative colitis. We found it possible to add an amino group on the aromatic moiety of our reported 1-[(1-acyl-4-piperidyl)methyl]-1H-2-methylimidazo[4,5-c]pyridine derivatives or on British Biotech compounds BB-882 and BB-823 maintaining a high level of activity as PAF antagonist. A selected compound UR-12715 (49c) showed an IC(50) of 8 nM in the in vitro PAF-induced aggregation assay, and an ID(50) of 29 microg/kg in the in vivo PAF-induced hypotension test in normotensive rats. Through attachment of 49c to the 5-ASA via azo functionality we obtained UR-12746 (70). Pharmacokinetics experiments with [14C]-70 allow us to reach the following conclusions, critical in the design of these new prodrugs of 5-ASA. Neither the whole molecule 70 nor the carrier 49c were absorbed after oral administration of [14C]-70 in rat as was demonstrated by the absence of plasma levels of radioactivity and the high recovery of it in feces. Effective cleavage of azo bond (84%) by microflora in the colon is achieved. These facts ensure high topical concentrations of 5-ASA and 49c in the colon. Additionally, 70 exhibited a potent anticolitic effect in the trinitrobenzenesulfonic acid-induced colitis model in the rat. This profile suggests that UR-12746 (70) provides an attractive new approach to the treatment of ulcerative colitis.

Synthesis and SAR of a new series of COX-2-selective inhibitors: pyrazolo[1,5-a]pyrimidines.

The synthesis and pharmacological activity of a series of bicyclic pyrazolo[1,5-a]pyrimidines as potent and selective cyclooxygenase-2 (COX-2) inhibitors are described. The new compounds were evaluated both in vitro (COX-1 and COX-2 inhibition in human whole blood) and in vivo (carrageenan-induced paw edema and air-pouch model). Modification of the pyrimidine substituents showed that 6,7-disubstitution provided the best activity and led to the identification of 3-(4-fluorophenyl)-6,7-dimethyl-2-(4-methylsulfonylphenyl)pyrazolo[1,5-a]pyrimidine (10f) as one of the most potent and selective COX-2 inhibitor in this series.

Protective effect of UR-12670 on chronic nephropathy induced by warm ischaemia in ageing uninephrectomized rats.

BACKGROUND: In young animals, renal ischaemia/reperfusion injury and mass reduction are associated with chronic lesions that mimic those found in chronic rejection. We have shown that the phospholipid platelet-activating factor (PAF) participates in young animals in such chronic nephropathy. Here we examine the long-term effects of the orally active PAF antagonist, UR-12670 in ageing uninephrectomized rats exposed to prolonged warm ischaemia. METHODS: Fifteen- to eighteen-month-old uninephrectomized male Sprague-Dawley rats were allocated into three groups and followed for 16 weeks: UNx, rats without ischaemia; UNxISC, ischaemic kidney (60 min), and UNxISC+UR, ischaemic kidney and UR-12670 from day 0 to the 16th week. Serum creatinine and proteinuria were monitored every 4 weeks. At the end of the study, conventional histology was performed and monocyte-macrophages were identified with the specific monoclonal antibody ED-1. RESULTS: The UNxISC group had severe acute renal failure with a high mortality rate, which was associated with incomplete restoration of renal function. Renal insufficiency in this group was sustained throughout the follow-up. Both UNx and UNxISC groups developed progressive proteinuria from the 12th week. Though UNxISC+UR group showed similar acute renal failure and mortality rate to the ischaemic non-treated group, serum creatinine decreased to levels similar to UNx group, which were maintained until the end of the study. Treatment of ischaemic kidneys with UR-12670 produced a slight decrease in 24-h proteinuria and a reduction in glomerulosclerosis, the mean tubulointerstitial score and number of monocyte-macrophages to values similar to UNx group. CONCLUSIONS: The chronic administration of the PAF antagonist UR-12670 attenuates the long-term effects of ischaemia-reperfusion injury in uninephrectomized ageing rats. The beneficial effect of this agent suggests that PAF contributes to the progression to late renal damage in this model.

Effect of 4-trifluoromethyl derivatives of salicylate on nuclear factor kappaB-dependent transcription in human astrocytoma cells.

1. The effect of two derivatives of salicylate, 2-hydroxy-4-trifluoromethylbenzoic acid (HTB) and 2-acetoxy-4-trifluoromethylbenzoic acid (triflusal), on the expression of several proteins displaying pro-inflammatory activities the regulation of which is associated to the transcription factor NF-kappaB, was assayed in the human astrocytoma cell line 1321N1. 2. Tumour necrosis factor-alpha (TNF-alpha) activated NF-kappaB as judged from both the appearance of kappaB-binding activity in the nuclear extracts, the degradation of IkappaB proteins in the cell lysates, and the activation of IkappaB kinases using an immunocomplex kinase assay with glutathione S-transferase (GST)-IkappaB proteins as substrates. 3. HTB up to 3 mM did not inhibit the nuclear translocation of NK-kappaB/Rel proteins as judged from electrophoretic mobility-shift assays; however, HTB inhibited the degradation of IkappaBbeta without significantly affecting the degradation of both IkappaBalpha and IkappaBepsilon. 4. In keeping with their inhibitory effect on IkappaBbeta degradation in the cell lysates, both HTB and triflusal inhibited the phosphorylation of GST-IkappaBbeta elicited by TNF-alpha, without affecting the phosphorylation of GST-IkappaBalpha. 5. The effect of both HTB and triflusal on kappaB-dependent trans-activation was studied by assaying the expression of both cyclo-oxygenase-2 (COX-2) and vascular cell adhesion molecule-1 (VCAM-1). HTB and triflusal inhibited in a dose-dependent manner the expression of COX-2 and VCAM-1 mRNA and the induction of COX-2 protein at therapeutically relevant concentrations. 6. These findings show the complexity of the biochemical mechanisms underlying the activation of NF-kappaB in the different cell types and extend the anti-inflammatory effects of HTB and triflusal to neural cells.

Efectos del triflusal y la aspirina sobre los mediadores inflamatorios cardiovasculares inducidos por NF- kB / Effects of trifusal and aspirin over imflamatory cardiovascular mediators mediated by NF-kB

El factor de transcripción nuclear NF-kB controla la expresión de diversos genes implicados en la patogénesis de la ateroclerosis. El triflusal (ácido 2-acetoxi-4-trifluorometilbenzoico) es un fármaco antiagregante que, aunque relacionado estructuralmente con la aspirina y otros salicilatos, muestra un perfil farmacológico y farmacocinético característico. Dado que recientemente se ha demostrado que los salicilatos pueden inhibir el NF-kB, el objetivo del presente estudio ha sido probar la actividad inhibitoria tanto del triflusal como de su metabolito desacetilado, el HTB, sobre la activación de NF-kB. Los resultados aquí descritos muestran que ambos compuestos, trifulsal y HTB, son inhibidores de la activación de NF-kB más potentes que la aspirina o el salicilato, y como consecuencia de ello, pueden bloquear la inducción de la síntesis de citocinas (TNF-a), quimiocinas (MCP-1), moléculas de adhesión (VCAM-1) y enzimas proinflamatorios (COX-2, NOS 2).Además, a diferencia de la aspirina, estos efectos antiinflamatorios del trifulsal se alcanzan a concentraciones similares a las obtenidas en su uso terapeútico como fármaco antiagregante plaquetario. El trifulsal puede ejercer efectos antiinflamatorios en trastornos cardiovasculares en los que se ha observado que genes controlados por el NF-kB están sobrexpresados (AU)

No disponible

Intestinal anti-inflammatory activity of UR-12746, a novel 5-ASA conjugate, on acute and chronic experimental colitis in the rat.

The present study was undertaken to investigate the intestinal anti-inflammatory effects of UR-12746 on the acute and chronic stages of a trinitrobenzene sulphonic acid (TNBS) experimental model of inflammatory bowel disease (IBD) in the rat. UR-12746 is a novel, locally-acting compound which combines, through an azo bond, 5-aminosalicylic (5-ASA) and UR-12715, a potent platelet activating factor (PAF)-antagonist. UR-12746 oral pretreatment of colitic rats (50 and 100 mg kg(-1)) reduced acute colonic damage when evaluated 2 days after colonic insult. Postreatment for 4 weeks with UR-12746 (50 and 100 mg kg(-1)) resulted in a faster recovery of the damaged colonic mucosa, which was macroscopically significant from the third week. The intestinal anti-inflammatory effect of UR-12746 was associated with a decrease in leukocyte infiltration in the colonic mucosa, which was evidenced both biochemically, by a reduction in myeloperoxidase activity, and histologically, by a lower leukocyte count after morphometric analysis. This effect was higher than that seen with sulphasalazine, when assayed at the same doses and in the same experimental conditions. Several mechanisms can be involved in the beneficial effects showed by UR-12746: inhibition of leukotriene B(4) synthesis in the inflamed colon, improvement of the altered colonic oxidative status, and reduction of colonic interleukin-1beta production. The results suggest that the intestinal anti-inflammatory activity of UR-12746 can be attributed to the additive effects exerted by 5-ASA and UR-12715, the PAF antagonist compound, that are released in the colonic lumen after reduction of the azo bond by the intestinal bacteria.

In vitro inhibitory effect of rupatadine on histamine and TNF-alpha release from dispersed canine skin mast cells and the human mast cell line HMC-1.

OBJECTIVE AND DESIGN: To examine the inhibitory potential of rupatadine, a new H1-antihistamine and anti-PAF agent, on histamine and TNF-alpha release. Comparison with an H1-antihistamine (loratadine) and a PAF-antagonist (SR-27417A). MATERIAL: Dispersed canine skin mast cells were used to assess the effect of the drugs tested on FcepsilonRI-dependent and -independent histamine release; the human HMC-1 cell line was used to study TNF-alpha release. TREATMENT AND METHODS: Before stimulation mast cell populations were treated with increasing concentrations of rupatadine, loratadine and SR-27417A. Histamine and TNF-alpha release were measured following 15-30 min and 3 h activation, respectively. RESULTS: The IC50 for rupatadine in A23187, concanavalin A and anti-IgE induced histamine release was 0.7+/-0.4 microM, 3.2+/-0.7 microM and 1.5+/-0.4 microM, respectively whereas for loratadine the IC50 was 2.1+/-0.9 microM, 4.0+/-1.3 M and 1.7+/-0.5 microM. SR-27417A exhibited no inhibitory effect. Rupatadine, loratadine and SR-27417A inhibited TNF-alpha release with IC50 2.0+/-0.9 microM, 2.1+/-1.1 M and 4.3+/-0.6 microM, respectively. CONCLUSIONS: Rupatadine and loratadine showed similar inhibitory effect on histamine and TNF-alpha release, whereas SR-27417A only exhibited inhibitory effect against TNF-alpha.