RESUMEN
Ponatinib may be effective in chronic myeloid leukemia (CML) patients after failure of first/second line therapies. Although its efficacy for minimum plasma concentrations (Cmin) is >21.3 ng/mL (equal to 40 nM), ponatinib may cause adverse events (AE) that require dose optimization. The present study was aimed at investigating any possible correlations among ponatinib dose, plasma concentration, molecular response (MR), and tolerability in a real-world setting. Clinical and laboratory records (including MR and drug plasma concentrations) of 32 CML patients treated with ponatinib were harvested and analyzed. Twenty-seven patients (71%) had ponatinib Cmin values > 21.3 ng/mL, but Cmin values > 10.7 ng/mL (considered efficacious in BCR-Abl unmutated patients) were achieved by 80% of the patients receiving ≥30 mg/day and 45% of the subjects treated with 15 mg/day. No significant correlations were identified among clinical efficacy, tolerability, daily dose, and plasma concentration. Notably, patients who underwent dose tapering for tolerability or safety reasons did not experience treatment failure. In a real-world setting, adjustment of ponatinib daily doses lower than those registered may maintain therapeutic efficacy while reducing the risk of vascular events and improving tolerability. Further studies are warranted to confirm the present results in a larger cohort of patients.
Asunto(s)
Adenocarcinoma/historia , Neoplasias del Colon/historia , Personajes , Medicina Legal , Momias/historia , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adenocarcinoma/terapia , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Neoplasias del Colon/terapia , Historia del Siglo XVI , Humanos , Italia , Masculino , Momias/patologíaRESUMEN
The aim of this study was to explore the pharmacokinetics of the two main active compounds (THC and CBD) contained in the cannabis oil extract Bedrocan® in fasting and fed dogs. Bedrocan® (20% delta-9-tetrahydrocannabinol [THC] and 0.5% cannabidiol [CBD]) was administered at 1.5 and 0.037â¯mg/kg THC and CBD, respectively in fasted and fed dogs according to a 2â¯×â¯2 cross over study design. The quantification of the two active ingredients was performed by LC/MS. No detectable concentrations of CDB were found at any collection time. THC was quantifiable from 0.5 to 10â¯h, although there was large inter-subject variability. Fed dogs showed a longer absorption phase (Tmax 5 vs 1.25â¯h) and lower maximal blood concentration (7.1 vs 24â¯ng/mL) compared with the fasted group. A larger AUC was found in the fasted group; the relative oral bioavailability in fed animals was 48.22%.
Asunto(s)
Cannabidiol/farmacocinética , Perros/metabolismo , Dronabinol/farmacocinética , Animales , Estudios Cruzados , Femenino , Privación de Alimentos , Extractos Vegetales/farmacocinética , Distribución AleatoriaRESUMEN
A novel aqueous in situ derivatization procedure with propyl chloroformate (PCF) for the simultaneous, quantitative analysis of Δ9 -tetrahydrocannabinol (THC), 11-hydroxy-Δ9 -tetrahydrocannabinol (OH-THC) and 11-nor-Δ9 -tetrahydrocannabinol-carboxylic acid (THC-COOH) in human blood and urine is proposed. Unlike current methods based on the silylating agent [N,O-bis(trimethylsilyl)trifluoroacetamide] added in an anhydrous environment, this new proposed method allows the addition of the derivatizing agent (propyl chloroformate, PCF) directly to the deproteinized blood and recovery of the derivatives by liquid-liquid extraction. This novel method can be also used for hydrolyzed urine samples. It is faster than the traditional method involving a derivatization with trimethyloxonium tetrafluoroborate. The analytes are separated, detected and quantified by gas chromatography-mass spectrometry in selected ion monitoring mode (SIM). The method was validated in terms of selectivity, capacity of identification, limits of detection (LOD) and quantification (LOQ), carryover, linearity, intra-assay precision, inter-assay precision and accuracy. The LOD and LOQ in hydrolyzed urine were 0.5 and 1.3 ng/mL for THC and 1.2 and 2.6 ng/mL for THC-COOH, respectively. In blood, the LOD and LOQ were 0.2 and 0.5 ng/mL for THC, 0.2 and 0.6 ng/mL for OH-THC, and 0.9 and 2.4 ng/mL for THC-COOH, respectively. This method was applied to 35 urine samples and 50 blood samples resulting to be equivalent to the previously used ones with the advantage of a simpler method and faster sample processing time. We believe that this method will be a more convenient option for the routine analysis of cannabinoids in toxicological and forensic laboratories.
Asunto(s)
Dronabinol , Toxicología Forense/métodos , Extracción Líquido-Líquido/métodos , Dronabinol/análogos & derivados , Dronabinol/sangre , Dronabinol/aislamiento & purificación , Dronabinol/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Límite de Detección , Modelos Lineales , Reproducibilidad de los ResultadosRESUMEN
A sensitive and reliable method for extraction and quantification of benzoylecgonine (BZE) and cocaine (COC) in urine is presented. Propyl-chloroformate was used as derivatizing agent, and it was directly added to the urine sample: the propyl derivative and COC were then recovered by liquid-liquid extraction procedure. Gas chromatography-mass spectrometry was used to detect the analytes in selected ion monitoring mode. The method proved to be precise for BZE and COC both in term of intraday and interday analysis, with a coefficient of variation (CV)<6%. Limits of detection (LOD) were 2.7 ng/mL for BZE and 1.4 ng/mL for COC. The calibration curve showed a linear relationship for BZE and COC (r2>0.999 and >0.997, respectively) within the range investigated. The method, applied to thirty authentic samples, showed to be very simple, fast, and reliable, so it can be easily applied in routine analysis for the quantification of BZE and COC in urine samples.
Asunto(s)
Cocaína/análogos & derivados , Cocaína/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Narcóticos/orina , Toxicología Forense , Formiatos/química , Humanos , Límite de DetecciónRESUMEN
OBJECTIVE: This study was aimed at investigating whether the ß2 -adrenoceptor agonist, salbutamol, could modulate RhoA activation in normal and homologously desensitized bronchial smooth muscle cells (BSMC). METHODS: Serum-starved BSMCs were stimulated with the Rho-activating compound calpeptin in the presence or absence of salbutamol, the Epac activator, 8-pCPT-2'-O-Me-cAMP, or the site-selective activator of cAMP-dependent protein kinase A (PKA), 6-Bnz-cAMP. Activated RhoA was assessed by immunocytochemical detection and by RhoA G-LISA assay. KEY FINDINGS: Stimulation with calpeptin caused translocation of RhoA from cytosol to plasma membrane, a condition required for the functional coupling of RhoA with its cellular targets. Pretreatment with salbutamol 10 µm for 15 min was found to block calpeptin-induced activation of RhoA in normal, but not in homologously desensitized cells. Pretreatment of calpeptin-stimulated BSMC with 8-pCPT-2'-O-Me-cAMP or 6-Bnz-cAMP could reproduce the effect of salbutamol. CONCLUSIONS: These findings demonstrated that salbutamol inhibits RhoA activation in human BSMC through ß2 -adrenoceptor/Epac/PKA pathway. An important pharmacological implication of these finding is the possible contribution of RhoA pathway to the molecular mechanism involved in airway smooth muscle relaxation caused by acute/chronic exposure to ß2-adrenoceptor agonists.
Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2/farmacología , Albuterol/farmacología , Bronquios/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Agonistas de Receptores Adrenérgicos beta 2/administración & dosificación , Albuterol/administración & dosificación , Bronquios/citología , Línea Celular , Membrana Celular/metabolismo , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacología , Citosol/metabolismo , Dipéptidos/farmacología , Humanos , Datos de Secuencia Molecular , Miocitos del Músculo Liso/metabolismo , Proteína de Unión al GTP rhoA/metabolismoRESUMEN
This study evaluated the relationship between the plasma concentration of l-methadone and response to methadone in real-world patients, in order to identify a minimum plasma concentration above which methadone treatment is effective. Ninety-four patients with opioid dependence under maintenance methadone treatment were consecutively recruited. Response was defined as negative urine analyses in the three weeks prior to the blood sampling. The percentage of participants with a plasma l-methadone concentration between 100 and 250 ng/ml was 54.2% among those with a methadone dosage ≥60 mg/day. Plasma l-methadone concentrations were significantly higher in patients with negative urine analyses compared with those with positive urine analyses (median 93 vs. 77 ng/ml, Mann-Whitney test, P<0.05). Above plasma l-methadone concentrations of 200 ng/ml no heroin use was reported and urine analyses were negative. Moreover, above concentrations of 250 ng/ml craving was absent. Examination of demographic correlates of treatment outcome indicated that older age, a stable job and being married were protective against the use of heroin. Mean plasma l-methadone concentration was significantly lower in patients who used cannabis compared with those who did not use cannabis, after adjusting for methadone dosage. In conclusion our results identify specific cut-offs for plasma l-methadone concentrations about which therapeutic response is observed and provide new evidence that therapeutic response is associated with patient׳s demographic characteristics. This underscores the need to monitor plasma methadone concentrations as part of Drug Addiction Services routine practice, in order to provide an objective framework for changing the methadone dosage.
Asunto(s)
Metadona/sangre , Metadona/uso terapéutico , Tratamiento de Sustitución de Opiáceos/métodos , Trastornos Relacionados con Opioides/sangre , Trastornos Relacionados con Opioides/tratamiento farmacológico , Adulto , Estudios Transversales , Dependencia de Heroína/sangre , Dependencia de Heroína/diagnóstico , Dependencia de Heroína/tratamiento farmacológico , Humanos , Metadona/química , Persona de Mediana Edad , Trastornos Relacionados con Opioides/diagnóstico , Estereoisomerismo , Resultado del Tratamiento , Adulto JovenRESUMEN
Microparticles (MPs) are membrane fragments that may play a role in the pathogenesis of chronic respiratory diseases. We aimed to investigate whether human monocytes/macrophage-derived MPs could induce a pro-inflammatory phenotype in human bronchial smooth muscle cells (BSMC) and the effect of montelukast in this setting. Experimental methods included isolation of human monocytes/macrophages and generation of monocyte-derived MPs, RT-PCR analysis of gene expression, immunoenzymatic determination of pro-inflammatory factor release, bioluminescent assay of intracellular cAMP levels and electromobility shift assay analysis of NF-κB nuclear translocation. Stimulation of human BSMC with monocyte-derived MPs induced a pro-inflammatory switch in human BSMC by inducing gene expression (COX-2 and IL-8), protein release in the supernatant (PGE2 and IL-8), and heterologous ß2-adrenoceptor desensitization. The latter effect was most likely related to autocrine PGE2 since pre-treatment with COX inhibitors restored the ability of salbutamol to induce cAMP synthesis in desensitized cells. Challenge with MPs induced nuclear translocation of NF-κB and selective NF-κB inhibition decreased MP-induced cytokine release in the supernatant. Montelukast treatment prevented IL-8 release and heterologous ß2-adrenoceptor desensitization in human BSMC exposed to monocyte-derived MPs by blocking NF-κB nuclear translocation. These findings provide evidence on the role of human monocyte-derived MPs in the airway smooth muscle phenotype switch as a novel potential mechanism in the progression of chronic respiratory diseases and on the protective effects by montelukast in this setting.
Asunto(s)
Acetatos/farmacología , Antiasmáticos/farmacología , Bronquios/citología , Micropartículas Derivadas de Células/inmunología , Monocitos/inmunología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/inmunología , Quinolinas/farmacología , Transporte Activo de Núcleo Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/inmunología , Ciclopropanos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Interleucina-8/genética , Interleucina-8/inmunología , Monocitos/citología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , FN-kappa B/análisis , FN-kappa B/inmunología , FN-kappa B/metabolismo , Receptores Adrenérgicos beta/inmunología , Transducción de Señal/efectos de los fármacos , SulfurosRESUMEN
Montelukast (MK) is a potent cysteinyl-leukotriene receptor antagonist that causes dose-related improvements in chronic asthma. We sought to determine whether MK was able to prevent salbutamol-induced tolerance in airway smooth muscle. Homologous ß2-adrenoceptor desensitisation models were established in guinea-pigs and in human bronchial smooth muscle cells (BSMC) by chronic salbutamol administration. Characterisation tools included measurement of the response of tracheal smooth muscle tissues to salbutamol, analysis of gene expression and receptor trafficking, evaluation of intracellular cAMP levels and phosphodiesterase (PDE) activity in human bronchial smooth muscle cells. Salbutamol-induced ß2-adrenoceptor desensitisation was characterised by ß2-agonist hyporesponsiveness (-30%, p < 0.001) in desensitised tracheal smooth muscle, as compared to controls. MK, given intraperitoneally at 5 mg/kg/day for 6 consecutive days, completely restored tissue responsiveness to salbutamol. Prolonged salbutamol treatment significantly decreased cAMP synthesis, induced a complete removal of the ß2-adrenoceptor from plasma membrane with a parallel increase in the cytosol and increased PDE4D5 gene transcription and PDE activity in human bronchial smooth muscle cells. In homologously desensitised BSMC, MK 30 µM for 24 h was able to prevent salbutamol subsensitivity and such an effect was associated with inhibition of salbutamol-induced PDE4 activity and restoration of membrane ß2-adrenoceptor expression and function. These findings suggest the presence of a favourable interaction between MK and ß2-adrenoceptor agonists that might improve the therapeutic index of bronchodilators in patients with chronic respiratory diseases.
Asunto(s)
Acetatos/farmacología , Albuterol/farmacología , Broncodilatadores/farmacología , Antagonistas de Leucotrieno/farmacología , Quinolinas/farmacología , Acetatos/administración & dosificación , Albuterol/administración & dosificación , Animales , Bronquios/citología , Bronquios/efectos de los fármacos , Bronquios/metabolismo , Broncodilatadores/administración & dosificación , Membrana Celular/metabolismo , AMP Cíclico/metabolismo , Ciclopropanos , Citosol/metabolismo , Relación Dosis-Respuesta a Droga , Tolerancia a Medicamentos , Perfilación de la Expresión Génica , Cobayas , Humanos , Inyecciones Intraperitoneales , Antagonistas de Leucotrieno/administración & dosificación , Masculino , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Quinolinas/administración & dosificación , Receptores de Leucotrienos/efectos de los fármacos , Receptores de Leucotrienos/metabolismo , Sulfuros , Factores de Tiempo , Tráquea/efectos de los fármacos , Tráquea/metabolismoRESUMEN
A series of novel indole-containing diarylisoxazoles has been synthesised, based on our previous work on the synthesis and pro-apoptotic antitumour activity of indole-based diaryl 1,2,4-oxadiazoles. Concise synthetic routes to both 3-(indol-2-yl)-5-phenylisoxazoles and 5-(indol-2-yl)-3-phenylisoxazoles have been developed with full regiochemical control, bearing substituents on the indole ring, indole nitrogen, and/or phenyl group. Additionally a series of the related 5-(1H-indol-5-yl)-3-phenylisoxazoles has been prepared. In vitro evaluation in human cancer cell lines Colo320 (colon) and Calu-3 (lung) revealed preferential antiproliferative activity within the 5-(indol-5-yl)-3-phenylisoxazole series (low micromolar IC(50)). Further analysis revealed the ability of the indol-5-yl series to induce expression of effector caspases-3 and -7, and retention of viability of the human bronchial smooth muscle cell (BSMC) control cell population (particularly for compounds 18c and 18e).
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Indoles/química , Isoxazoles/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Isoxazoles/síntesis química , Isoxazoles/química , Estructura Molecular , Músculo Liso/citología , Músculo Liso/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
AIMS: Microparticles are membrane vesicles shed by cells upon activation and/or apoptosis. Microparticles are involved in several processes, including blood coagulation and thrombosis. In addition to their role in the regulation of lipid metabolism, peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists exert other effects, both dependent on and independent of PPAR-γ activation. Some PPAR-γ agonists have been linked to an increased risk of thrombotic diseases. We aimed to investigate the potential role of PPAR-γ agonists on the generation of procoagulant microparticles by human monocytes/macrophages. METHODS AND RESULTS: Monocytes/macrophages were isolated from the buffy coats of normal donors. Cells were incubated with three structurally unrelated PPAR-γ agonists, namely, rosiglitazone, pioglitazone, and 15-deoxy-Δ(12,14)-prostaglandin J(2). Microparticle generation was assessed as phosphatidylserine concentration by a prothrombinase assay, after capturing the microparticles onto annexin V-coated wells. Intracellular calcium concentration was assessed by a fluorescent probe. Extracellular signal-regulated kinase (ERK) phosphorylation was assessed by western blot. Tissue factor expression on microparticles was measured with a one-stage clotting assay. Rosiglitazone and 15-deoxy-Δ(12,14)-prostaglandin J(2), but not pioglitazone, caused a dose-dependent, significant increase in intracellular calcium mobilization and tissue factor-bearing microparticle generation. EGTA inhibited microparticle generation. The specific PPAR-γ inhibitor, GW9662, also inhibited microparticle generation. Finally, rosiglitazone and 15-deoxy-Δ(12,14)-prostaglandin J(2) caused phosphorylation of ERK; inhibition of ERK by PD98059 inhibited microparticle generation. CONCLUSION: The PPAR-γ agonists rosiglitazone and 15-deoxy-Δ(12,14)-prostaglandin J(2), but not pioglitazone, caused an increase in procoagulant, tissue factor-bearing microparticle generation by human monocytes/macrophages. The effect was dependent on ERK phosphorylation and partly mediated through intracellular calcium mobilization; however, direct activation of the PPAR-γ ligand was also involved.
Asunto(s)
Micropartículas Derivadas de Células/efectos de los fármacos , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , PPAR gamma/agonistas , PPAR gamma/metabolismo , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Micropartículas Derivadas de Células/metabolismo , Células Cultivadas , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Macrófagos/citología , Macrófagos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Monocitos/citología , Monocitos/metabolismo , Pioglitazona , Rosiglitazona , Transducción de Señal/fisiología , Tiazolidinedionas/farmacologíaRESUMEN
BACKGROUND AND PURPOSE: ß2-Adrenoceptor agonists are important therapeutic agents in the treatment of asthma and chronic obstructive pulmonary disease. The regular use of these drugs has been associated with proasthmatic-like changes that limit their efficacy and increase the risk of severe adverse reactions. We investigated whether the peroxisome-proliferator-activated receptor (PPAR)γ agonist rosiglitazone modulated salbutamol-induced ß2-adrenoceptor desensitization in vivo and in vitro. EXPERIMENTAL APPROACH: An in vivo model of homologous ß2-adrenoceptor desensitization, established in guinea-pigs by administering salbutamol continuously, was used to study the ability of rosiglitazone to prevent ß2-adrenoceptor tolerance. In vitro experiments on human bronchial smooth muscle cells were performed to increase the clinical relevance of the study. KEY RESULTS: In tracheal smooth muscle tissues from desensitized animals, we observed a decrease in the protective effect of salbutamol on carbachol-induced contraction, a hyperresponsiveness to cholinergic stimuli, a modest underexpression of ß2-adrenoceptor gene and a marked decrease in ß-adrenoceptor number, relative to control values. Treatment with rosiglitazone preserved salbutamol relaxant activity, mitigated carbachol hyperresponsiveness and partially restored ß2-adrenoceptor binding sites in tracheal tissues from homologously desensitized animals. The highly selective PPARγ agonist, GW1929, reproduced the effect of rosiglitazone, in vivo. In vitro ß2-adrenoceptor desensitization decreased salbutamol-mediated cAMP production, without affecting forskolin responses and ß2-adrenoceptor expression. Rosiglitazone and 15-deoxy-Δ¹²(,)¹4-prostaglandin J2 restored salbutamol sensitivity in homologously desensitized cells. CONCLUSIONS AND IMPLICATIONS: These data suggest a potential pharmacodynamic interaction between PPARγ agonists and salbutamol on airway smooth muscle responsiveness, supporting the therapeutic potential of this combination in chronic airway disease.
Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2/farmacología , Albuterol/farmacología , Músculo Liso/efectos de los fármacos , Receptores Adrenérgicos beta 2/metabolismo , Sistema Respiratorio/efectos de los fármacos , Tiazolidinedionas/farmacología , Animales , Asma/tratamiento farmacológico , Carbacol/farmacología , Células Cultivadas , Dexametasona/farmacología , Tolerancia a Medicamentos , Cobayas , Humanos , Técnicas In Vitro , Masculino , Músculo Liso/metabolismo , PPAR gamma/agonistas , Enfermedad Pulmonar Obstructiva Crónica , ARN Mensajero/análisis , Receptores Adrenérgicos beta 2/genética , Sistema Respiratorio/metabolismo , Rosiglitazona , Tráquea/efectos de los fármacos , Tráquea/metabolismoRESUMEN
A series of new indole-based 3,5-disubstituted 1,2,4-oxadiazoles has been designed and synthesised as potential pro-apoptotic antitumour agents, via the base-catalysed condensation reaction between substituted amidoximes and indole esters. Evaluation of antiproliferative activity against the human cancer cell lines COLO 320 (colorectal) and MIA PACA-2 (pancreatic) revealed IC(50) values in the low micromolar range. Selected compounds were able to trigger apoptosis in sensitive cell lines, for example via activation of caspase-3/7, demonstrating that indole-based oxadiazoles possess in vitro antitumour and pro-apoptotic activity.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Indoles/química , Indoles/farmacología , Oxadiazoles/química , Oxadiazoles/farmacología , Antineoplásicos/síntesis química , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Diseño de Fármacos , Humanos , Indoles/síntesis química , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Oxadiazoles/síntesis química , Neoplasias Pancreáticas/tratamiento farmacológico , Relación Estructura-ActividadRESUMEN
The non-steroidal anti-inflammatory drug (NSAID) sulindac exhibits cyclooxygenase (COX)-dependent and COX-independent chemopreventive properties in human cancer. The present study was aimed at investigating whether the hydroxamic acid substitution for the carboxylic acid group could enhance the in vitro antitumor and antiangiogenic activities of sulindac. Characterization tools used on this study included analyses of cell viability, caspase 3/7 induction, DNA fragmentation, and gene expression. Our findings demonstrate that the newly synthesized hydroxamic acid derivative of sulindac and its sulfone and sulfide metabolites were characterized by a good anticancer activity on human pancreatic and colon cancer cells, both in terms of potency (IC(50) mean values from 6 ± 1.1 µM to 64 ± 1.1 µM) and efficacy (E(max) of â¼100%). Hydroxamic acid derivatives trigger a higher degree of apoptosis than carboxylic acid counterparts, increase bax/bcl-2 expression ratio and induce caspase 3/7 activation. Most notably, these compounds significantly inhibit proangiogenic growth factor-stimulated proliferation of vascular endothelial cell (HUVEC) at sub-micromolar concentrations. Our data also provide evidence that the COX-active metabolite of sulindac hydroxamic acid were the most active of the series and selective inhibition of COX-1 but not COX-2 can mimic its effects, suggesting that COX inhibition could only play a partial role in the mechanism of compound action. In conclusion, these data demonstrate that substitution of the carboxylic acid group with the hydroxamic acid moiety enhances in vitro antiproliferative, proapoptotic and antiangiogenic properties of sulindac, therefore increasing the therapeutic potential of this drug.
Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Neoplasias del Colon/patología , Neoplasias Pancreáticas/patología , Sulindac/uso terapéutico , Inhibidores de la Angiogénesis/farmacología , Antiinflamatorios no Esteroideos/farmacología , Caspasa 3/metabolismo , Caspasa 7/metabolismo , Línea Celular Tumoral , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Sulindac/farmacologíaRESUMEN
In a previous report quaternary ammonium-chitosan conjugates (N(+)-Chs) endowed with intestinal drug permeability-enhancing properties were described. They are characterized by short pendant chains of n adjacent diethyl-dimethylene-ammonium groups substituted onto the primary amino group of the chitosan (Ch) repeating units. In the present work two N(+)-Chs, one having DS (degree of substitution)=59.2+/-4.5%, n=1.7+/-0.1 (N(+)(60)-Ch), the other one having DS=40.6+/-1.3%, n=3.0+/-0.2 (N(+)(40)-Ch) were used to synthesize novel multifunctional non-cytotoxic Ch derivatives, each carrying thiol along with quaternary ammonium groups (N(+)-Ch-SH), with increased potential to enhance transepithelial drug transport. They have been obtained by transforming the residual free amino groups of N(+)(60)-Ch and N(+)(40)-Ch into 3-mercaptopropionamide moieties. The former yielded 4.5+/-0.7% thiol-bearing groups, the latter, 5.2+/-1.1% of such groups, on a Ch repeating unit basis. The multifunctional derivatives have improved the ability of the parent N(+)-Chs to enhance the permeability of the water-soluble macromolecular fluorescein isothiocyanate dextran, MW 4400 Da (FD4) and that of the lipophilic dexamethasone (DMS) across the excised rat intestinal mucosa and Caco-2 cell monolayer, respectively. The data from the present work altogether point to a synergism of quaternary ammonium and thiol groups to improve the intestinal drug absorption enhancing properties of the multifunctional Ch derivatives.