RESUMEN
Six novel click-tambjamines (1-6) bearing an alkyl chain of varying length linked to the imine moiety have been formulated in nanostructured lipid carriers (NLCs) to evaluate their transmembrane anion transport activity both when free (i.e., not encapsulated) and nanoformulated. Nanostructured lipid carriers (NLCs) are an example of drug delivery systems (DDSs) that stand out because of their versatility. In this work we show that NLCs can be used to efficiently formulate highly lipophilic anionophores and experiments conducted in model liposomes reveal that these formulations are adequate to deliver anionophores without compromising their transport activity. This result paves the way to facilitate the study of highly lipophilic anionophores and their potential use as future drugs.
Asunto(s)
Portadores de Fármacos , Nanoestructuras , Sistemas de Liberación de Medicamentos , Liposomas , Lípidos , Tamaño de la PartículaRESUMEN
Cystic fibrosis (CF) is a genetic disease characterized by the lack of cystic fibrosis transmembrane conductance regulator (CFTR) protein expressed in epithelial cells. The resulting defective chloride and bicarbonate secretion and imbalance of the transepithelial homeostasis lead to abnormal airway surface liquid (ASL) composition and properties. The reduced ASL volume impairs ciliary beating with the consequent accumulation of sticky mucus. This situation prevents the normal mucociliary clearance, favouring the survival and proliferation of bacteria and contributing to the genesis of CF lung disease. Here, we have explored the potential of small molecules capable of facilitating the transmembrane transport of chloride and bicarbonate in order to replace the defective transport activity elicited by CFTR in CF airway epithelia. Primary human bronchial epithelial cells obtained from CF and non-CF patients were differentiated into a mucociliated epithelia in order to assess the effects of our compounds on some key properties of ASL. The treatment of these functional models with non-toxic doses of the synthetic anionophores improved the periciliary fluid composition, reducing the fluid re-absorption, correcting the ASL pH and reducing the viscosity of the mucus, thus representing promising drug candidates for CF therapy.
Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Fibrosis Quística/metabolismo , Células Epiteliales/metabolismo , Ionóforos , Mucosa Respiratoria/metabolismo , Línea Celular , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/patología , Células Epiteliales/patología , Humanos , Transporte Iónico/efectos de los fármacos , Ionóforos/síntesis química , Ionóforos/química , Ionóforos/farmacología , Moco/metabolismo , Mucosa Respiratoria/patologíaRESUMEN
Knoevenagel condensation was employed to generate a set of molecules potentially capable of inhibiting the RNA polymerase-σ70/σA interaction in bacteria. Synthesis was achieved via reactions between a variety of indole-7-carbaldehydes and rhodanine, N-allylrhodanine, barbituric acid or thiobarbituric acid. A library of structurally diverse compounds was examined by enzyme-linked immunosorbent assay (ELISA) to assess the inhibition of the targeted protein-protein interaction. Inhibition of bacterial growth was also evaluated using Bacillus subtilis and Escherichia coli cultures. The structure-activity relationship studies demonstrated the significance of particular structural features of the synthesized molecules for RNA polymerase-σ70/σA interaction inhibition and antibacterial activity. Docking was investigated as an in silico method for the further development of the compounds.
Asunto(s)
Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Transcripción Genética/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Bacillus subtilis/genética , Relación Dosis-Respuesta a Droga , Escherichia coli/genética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-ActividadRESUMEN
The search for small molecules capable of inhibiting transcription initiation in bacteria has resulted in the synthesis of N,N'-disubstituted hydrazines and imine-carbohydrazides comprised of indole, pyridine, pyrrole, furan and thiophene using the respective trichloroacetyl derivatives, carbohydrazides and aldehydes. Replacement of the indole moiety by smaller heterocycles linked by CONHNC linkers afforded a broad variety of compounds efficiently targeting the RNA polymerase-σ(70)/σ(A) interaction as determined by ELISA and exhibiting increased inhibition of the growth of Escherichia coli compared to Bacillus subtilis in culture. The structural features of the synthesized transcription initiation inhibitors needed for antibacterial activity were identified employing molecular modelling and structure-activity relationship (SAR) studies.
Asunto(s)
Antibacterianos/análisis , Furanos/farmacología , Indoles/farmacología , Complejos Multiproteicos/metabolismo , Piridinas/farmacología , Pirroles/farmacología , Tiofenos/farmacología , Iniciación de la Transcripción Genética/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/genética , Bacillus subtilis/crecimiento & desarrollo , ARN Polimerasas Dirigidas por ADN/metabolismo , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Furanos/síntesis química , Furanos/química , Indoles/síntesis química , Indoles/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Unión Proteica/efectos de los fármacos , Piridinas/síntesis química , Piridinas/química , Pirroles/síntesis química , Pirroles/química , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Relación Estructura-Actividad , Tiofenos/síntesis química , Tiofenos/químicaRESUMEN
Our ongoing research focused on targeting transcription initiation in bacteria has resulted in synthesis of several classes of mono-indole and mono-benzofuran inhibitors that targeted the essential protein-protein interaction between RNA polymerase core and σ(70)/σ(A) factors in bacteria. In this study, the reaction of indole-2-, indole-3-, indole-7- and benzofuran-2-glyoxyloyl chlorides with amines and hydrazines afforded a variety of glyoxyloylamides and glyoxyloylhydrazides. Similarly, condensation of 2- and 7-trichloroacetylindoles with amines and hydrazines delivered amides and hydrazides. The novel molecules were found to inhibit the RNA polymerase-σ(70)/σ(A) interaction as measured by ELISA, and also inhibited the growth of both Gram-positive and Gram-negative bacteria in culture. Structure-activity relationship (SAR) studies of the mono-indole and mono-benzofuran inhibitors suggested that the hydrophilic-hydrophobic balance is an important determinant of biological activity.
Asunto(s)
Antibacterianos/química , Bacterias/efectos de los fármacos , Bacterias/enzimología , Benzofuranos/química , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , Indoles/química , Activación Transcripcional/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Benzofuranos/síntesis química , Benzofuranos/farmacología , Humanos , Indoles/síntesis química , Indoles/farmacología , Modelos Moleculares , Relación Estructura-ActividadRESUMEN
The increasing resistance of bacteria against clinically approved antibiotics is resulting in an alarming decrease in therapeutic options for today's clinicians. We have targeted the essential interaction between bacterial RNA polymerase and σ(70)/σ(A) for the development of lead molecules exhibiting a novel mechanism of antibacterial activity. Several classes of structurally related bis-indole inhibitors of bacterial transcription initiation complex formation were synthesized and their antimicrobial activities were evaluated. Condensation of indole-7- and indole-2-carbohydrazides with 7- and 2-trichloroacetylindoles or indole-7- and indole-2-glyoxyloyl chlorides resulted in the successful synthesis of 7,7'-, 2,2'-, 2,7'- and 3,2'-linked bis-indole derivatives with -CO-NH-NH-CO- and -CO-CO-NH-NH-CO- linkers. Indole-7-glyoxyloyl chlorides were reacted with hydrazine hydrate in different ratios to afford respective -CO-CO-NH-NH-CO-CO- bis-indole or hydrazide derivatives. The resulting compounds were found to be active against the ß'-CH-σ(70)/σ interaction in ELISA assays and inhibited the growth of both Gram-positive and Gram-negative bacteria. Structure-activity relationship (SAR) studies were performed in order to identify the structural features of the synthesized inhibitors required for biological activity.
Asunto(s)
Bacillus subtilis/genética , Escherichia coli/genética , Indoles/síntesis química , Indoles/farmacología , Iniciación de la Transcripción Genética/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/crecimiento & desarrollo , ARN Polimerasas Dirigidas por ADN/metabolismo , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Indoles/químicaRESUMEN
A novel class of transmembrane anion carriers, the click-tambjamines, display remarkable anionophoric activities in model liposomes and living cells. The versatility of this building block for the generation of molecular diversity offers promise to develop future drugs based on this design.
Asunto(s)
Antineoplásicos/farmacología , Pirroles/farmacología , Células A549 , Aniones/síntesis química , Aniones/química , Aniones/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Transporte Iónico , Liposomas/química , Células MCF-7 , Modelos Moleculares , Estructura Molecular , Pirroles/síntesis química , Pirroles/química , Relación Estructura-ActividadRESUMEN
BACKGROUND: Precise mechanisms leading to restenosis are not fully understood. The type of implanted stent and the intensity of atherogenic processes may affects the restenosis rate. AIM: To compare the long-term effects of the coronary stent implantation - paclitaxel-eluting stent (PES) or bare-metal stents (BMS) - on endothelial-dependent flow-mediated dilation (FMD), platelet-derived growth factor (PDGF) and asymmetric dimethylarginine (ADMA) serum levels and to assess the relationship between FMD, PDGF, ADMA and every-stage in-stent restenosis (eISR). METHODS: The study population included 40 patients with coronary artery disease, who underwent elective percutaneous coronary intervention (PCI) of the left anterior descending artery (LAD) with stent implantation (PES - 21 patients; BMS - 19 patients). Follow-up examination was performed 12 months after PCI. RESULTS: There were no differences between the PES and the BMS patients regarding FMD (PES: 11.8+/-7.8%, BMS: 10.5+/-9.2%), PDGF (PES: 5540+/-2209 pg/ml, BMS: 4923+/-2924 pg/ml) and ADMA (PES: 0.474+/-0.04 micromol/l, BMS: 0.456+/-0.03 micromol/l) serum levels. The follow-up angiography was performed when clinically indicated in 25 patients: in 15 patients with PES and 10 patients with BMS implanted. The eISR was found in 12 subjects: in 7 (47%) with PES and in 5 (50%) with BMS (NS). In all patients with eISR, the FMD values were significantly lower (6.1+/-3.5%, p=0.003) compared to the patients without eISR (14.3+/-7.8%). FMD was the only independent risk factor for eISR (OR=0.631, 95% CI 0.412-0.942, p=0.0003). The cut-off point for FMD < or = 8.4% as a parameter predicting eISR was established (p=0.0001, sensitivity: 83.3%, specificity: 92.3%, PPV: 90.9%, NPV: 85.7%). CONCLUSIONS: The type of stent implanted into LAD does not affect the FMD, PDGF and ADMA serum levels assessed one-year after a PCI procedure. The occurrence of an early in-stent restenosis is associated with impaired FMD at the time of one-year follow-up.
Asunto(s)
Reestenosis Coronaria/prevención & control , Reestenosis Coronaria/fisiopatología , Estenosis Coronaria/terapia , Endotelio Vascular/fisiopatología , Stents/efectos adversos , Vasodilatación , Anciano , Angioplastia Coronaria con Balón/instrumentación , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Reestenosis Coronaria/etiología , Estenosis Coronaria/patología , Vasos Coronarios/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Polonia , Factores de Riesgo , Factores de TiempoRESUMEN
BACKGROUND AND PURPOSE: Cystic fibrosis (CF) is a lethal autosomal recessive genetic disease that originates from the defective function of the CF transmembrane conductance regulator (CFTR) protein, a cAMP-dependent anion channel involved in fluid transport across epithelium. Because small synthetic transmembrane anion transporters (anionophores) can replace the biological anion transport mechanisms, independent of genetic mutations in the CFTR, such anionophores are candidates as new potential treatments for CF. EXPERIMENTAL APPROACH: In order to assess their effects on cell physiology, we have analysed the transport properties of five anionophore compounds, three prodigiosines and two tambjamines. Chloride efflux was measured in large uni-lamellar vesicles and in HEK293 cells with chloride-sensitive electrodes. Iodide influx was evaluated in FRT cells transfected with iodide-sensitive YFP. Transport of bicarbonate was assessed by changes of pH after a NH4 + pre-pulse using the BCECF fluorescent probe. Assays were also carried out in FRT cells permanently transfected with wild type and mutant human CFTR. KEY RESULTS: All studied compounds are capable of transporting halides and bicarbonate across the cell membrane, with a higher transport capacity at acidic pH. Interestingly, the presence of these anionophores did not interfere with the activation of CFTR and did not modify the action of lumacaftor (a CFTR corrector) or ivacaftor (a CFTR potentiator). CONCLUSION AND IMPLICATIONS: These anionophores, at low concentrations, transported chloride and bicarbonate across cell membranes, without affecting CFTR function. They therefore provide promising starting points for the development of novel treatments for CF.
Asunto(s)
Bicarbonatos/metabolismo , Cloruros/metabolismo , Ionóforos/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cricetulus , Fibrosis Quística/tratamiento farmacológico , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Interacciones Farmacológicas , Humanos , Concentración de Iones de Hidrógeno , Yoduros/metabolismo , Transporte Iónico , Potenciales de la Membrana/efectos de los fármacos , RatasRESUMEN
Highly active transmembrane anion transporters have demonstrated their activity against antibiotic-resistant and clinically relevant bacterial strains. This type of compound offers promise as a strategy to develop novel antibacterial agents.