RESUMEN
This study focused on defining the in vitro behavior of amphiphilic poly-N-vinylpyrrolidone (Amph-PVP) nanoparticles toward whole blood, blood plasma and blood cells in order to assess nanoparticle blood compatibility. In addition, possible effects on endothelium cell growth/viability were evaluated. The Amph-PVP nanoparticles were formed via self-assembling in aqueous media and composed of a hydrophobic alkyl core and a hydrophilic PVP outer shell. Their blood compatibility was evaluated by investigating their effect on red blood cells (RBCs) or erythrocytes, white blood cells (WBCs) or leukocytes, platelets (PLTs) and on complement system activation. Our results clearly demonstrate that the Amph-PVP nanoparticles are stable in presence of blood serum, have no significant effects on the function of RBCs, WBCs, PLTs and complement system activation. The Amph-PVP nanoparticles did not show considerable hemolytic or inflammatory effect, neither influence on platelet aggregation, coagulation process, or complement activation at the tested concentration range of 0.05-0.5â¯mg/ml. The Amph-PVP nanoparticles did not exhibit any significant effect on HMEC-1 microvascular skin endothelial cells' growth in in vitro experiments. The excellent blood compatibility of the Amph-PVP nanoparticles and the lack of effect on endothelium cell growth/viability represent a crucial feature dictating their further study as novel drug delivery systems.
Asunto(s)
Materiales Biocompatibles , Plaquetas/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Leucocitos/efectos de los fármacos , Nanopartículas/toxicidad , Pirrolidinonas/toxicidad , Línea Celular , Células Endoteliales/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Humanos , Técnicas In Vitro , Nanopartículas/química , Pirrolidinonas/química , Piel/irrigación sanguínea , Piel/citologíaRESUMEN
The aim of the present study was to evaluate the cytotoxicity against MCF-7 cells and acute intraperitoneal toxicity of amphiphilic poly-N-vinylpyrrolidone nanoparticles to confirm possibility of their application for creation of novel drug delivery systems. The effect of cellular uptake of polymeric nanoparticles on human cancer cell line MCF-7 cells was investigated by MTT assay. MTT analysis showed that tested amphiphilic polymers were essentially non-toxic. In acute toxicity studies, LD50 and other toxicity indexes were evaluated, under which no deaths or treatment related complications were observed even in high concentration treatment for 14 days of experiment. For histological analysis, organs of the animals were weighed and examined. No animal died during the study and no significant changes have been observed regarding body weight, feed consumption, organ weight or histological data. Obtained results show that amphiphilic poly-N-vinylpyrrolidone nanoparticles possessed no toxicity against cells and in animals after intraperitoneal administration. Thus, amphiphilic PVP nanoparticles demonstrate high potential as carriers for novel high-effective drug delivery systems.
Asunto(s)
Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Nanopartículas/administración & dosificación , Polímeros/química , Pirrolidinonas/toxicidad , Animales , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/toxicidad , Peso Corporal/efectos de los fármacos , Femenino , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Células MCF-7 , Masculino , Ratones Endogámicos BALB C , Nanopartículas/química , Pirrolidinonas/administración & dosificación , Pruebas de Toxicidad AgudaRESUMEN
Previous studies have demonstrated functional roles for microRNAs (miRNAs) in various aspects of normal and malignant hematopoiesis, including lineage commitment, differentiation, apoptosis and maturation. In vivo delivery of naked DNA, oligonucleotides and miRNAs is complicated by their low stability, rapid degradation and inefficient delivery into target cells. In our experiments, we used a new type of polymer carriers to monitor the effects of miR-155 and antago-miR-155 on the morphology and genetics of Kasumi-1 cells. We obtained platelet-like cells from leukemic cells, and detected the expression of platelet marker genes after transfection with antago-miR-155. Our findings suggest that administration of miR mimics or antago-miRs as therapeutic agents is a desirable goal for future treatment of hematologic malignancies and that polymer-based carriers for the delivery of miR mimics or antago-miRs may provide a solution to the challenges of standard miR delivery approaches.
Asunto(s)
MicroARNs/genética , Polivinilos/metabolismo , Transfección , Línea Celular Tumoral , Forma de la Célula , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Expresión Génica , Terapia Genética , Humanos , Proteínas Luminiscentes/biosíntesis , Proteínas Luminiscentes/genética , Microscopía Fluorescente , Nanopartículas/química , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Polivinilos/química , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Interferencia de ARN , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Proteína 1 Compañera de Translocación de RUNX1 , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/metabolismo , Proteína Fluorescente RojaRESUMEN
Novel amphiphilic poly-N-vinylpyrrolidone derivatives with different molecular weight of hydrophilic PVP fragment and one secondary di-n-alkyl terminal hydrophobic fragment of different length were synthesized to compare their inclination for formation of nano-scaled micelle-like aggregates in aqueous media with previously studied primary n-alkyl terminated poly-N-vinylpyrrolidones. The behavior of amphiphilies in water solutions was studied and critical aggregation concentration values for prepared polymer samples were determined by fluorescence spectroscopy and compared with those for primary n-alkyl derivatives. Polymeric micelle-like particles with or without encapsulated drug were prepared using dialysis or solvent evaporation techniques. Indomethacin was incorporated into hydrophobic inner core of these nanoparticles as a typical model drug. Dynamic light-scattering studies determined that the average size of particles formed was from 90 nm up to 600 nm with monodisperse size distribution and the nanoparticle size slightly increased with the amount of indomethacin encapsulated into inner core of the particles. In vitro release experiments carried out at different medium pH values using indomethacin-loaded nanoparticles exhibited slow and steady drug release into the medium.
Asunto(s)
Portadores de Fármacos/química , Indometacina/farmacocinética , Nanopartículas/química , Pirrolidinonas/química , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacocinética , Composición de Medicamentos , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Indometacina/química , Cinética , Lípidos/química , Microscopía Electrónica de Transmisión , Nanopartículas/ultraestructura , Tamaño de la Partícula , Temperatura , Agua/químicaRESUMEN
Stearoyl-poly-N-vinylpyrrolidone (PVP-stear) of various molecular weights (M(n) = 1500-5500) self-assemble in aqueous medium. Particles prepared from PVP-stear were characterized in terms of shape and size distribution, and the mechanical stability of the particles was studied. The interaction of PVP-stear and its aggregates with blood components was investigated. Aggregates formed by the polymers with M(n) = 1500-3500 in the presence of human serum are stable. The direct lytic action of PVP-stear preparations was studied using sheep and human erythrocytes. The influence of PVP-stear aggregates on the activation of complement system both on classical and alternative pathways was examined. The aggregates prepared from PVP-stear of various molecular weights had no effect on the activation of the complement system.
Asunto(s)
Sangre/metabolismo , Polímeros/química , Pirrolidinonas/química , Estearatos/química , Animales , Activación de Complemento/efectos de los fármacos , Eritrocitos , Hemólisis/efectos de los fármacos , Humanos , Luz , Micelas , Modelos Biológicos , Peso Molecular , Tamaño de la Partícula , Polímeros/farmacología , Pirrolidinonas/farmacología , Conejos , Dispersión de Radiación , Oveja Doméstica , Estearatos/farmacologíaRESUMEN
Polymeric particles formed by stearoyl-poly-N-vinylpyrrolidone (PVP-stear) of M(n) = 2600 were obtained in aqueous solution, and their shape and size distribution were characterized. The size of the particles was shown to decrease with an increase in the ionic strength of the solution. Interaction of PVP-stear and its aggregates with model proteins (Bowman-Birk soybean proteinase inhibitor (BBI) and its hydrophobized derivatives) was studied. The possibility of inclusion of both native BBI and oleoylic derivative of BBI in the PVP-stear polymeric aggregates was investigated. It was established that polymeric particles with a diameter of 30 nm formed under certain concentration ratios between PVP-stear and poorly soluble dioleoyl BBI are capable of solubilization of dioleoyl BBI as well as prevention of its inactivation at low pH values.
Asunto(s)
Polímeros/química , Pirrolidinonas/química , Inhibidor de la Tripsina de Soja de Bowman-Birk/química , Cromatografía en Gel , Coloides/química , Portadores de Fármacos/farmacología , Microscopía Electrónica , Estearatos/químicaRESUMEN
Certain amphiphilic water-soluble polymers including amphiphilic derivatives of polyvinyl pyrrolidone (PVP) were found to be efficient steric protectors for liposomes in vivo. In this study, we have tried to develop synthetic pathways for preparing amphiphilic PVP and to investigate the influence of the hydrophilic/hydrophobic blocks on some properties of resulting polymers and polymer-coated liposomes. To prepare amphiphilic PVP with the end stearyl (S) or palmityl (P) residues, amino- and carboxy-terminated PVP derivatives were first synthesized by the free-radical polymerization of vinyl pyrrolidone in the presence of amino- or carboxy-mercaptans as chain transfer agents, and then modified by interaction of amino-PVP with stearoyl chloride or palmitoyl chloride, or by dicyclohexyl carbodiimide coupling of stearylamine with carboxy-PVP. ESR-spectra of the hydrophobic spin-probe, nitroxyl radical N-oxyl-2-hexyl-2-(10-methoxycarbonyl)decyl-4,4'-dimethyl oxazoline, in the presence of amphiphilic PVP demonstrated good accessibility of terminal P- and S-groups for the interaction with other hydrophobic ligands. Spontaneous micellization and low CMC values (in a low micromolar range) were found for amphiphilic PVP derivatives using the pyrene method. In general, S-PVP forms more stable micelles than P-PVP (at similar MW, CMC values for S-PVP are lower than for P-PVP). It was found that amphiphilic PVP incorporated into negatively charged liposomes effectively prevents polycation(poly-ethylpyridinium-4-vinylchloride)-induced liposome aggregation, completely abolishing it at ca. 10 mol% polymer content in liposomes. Additionally, the liposome-incorporated PVP prevents the fluorescence quenching of the membrane-incorporated hydrophobic fluorescent label [N-(4-fluoresceinthiocarbamoyl)dipalmitoyl-PE] by the free polycation. PVP-modified liposomes were loaded with a self-quenching concentration of carboxyfluorescein, and their destabilization in the presence of mouse serum was investigated following the release of free dye. Amphiphilic PVP with MW between 1,500 and 8,000 provides good steric protection for liposomes. The degree of this protection depends on both polymer concentration and molecular size of the PVP block.
Asunto(s)
Materiales Biocompatibles/síntesis química , Povidona/síntesis química , Animales , Materiales Biocompatibles/química , Portadores de Fármacos , Estabilidad de Medicamentos , Espectroscopía de Resonancia por Spin del Electrón , Colorantes Fluorescentes , Técnicas In Vitro , Liposomas , Ensayo de Materiales , Ratones , Micelas , Povidona/química , Electricidad Estática , Propiedades de Superficie , Tensoactivos/síntesis química , Tensoactivos/químicaRESUMEN
New controlled release water-soluble formulations of sorbic (2,4-hexadienoic) acid were prepared and their inhibitory activity on mycelium growth of Fusarium oxysporum f.sp. radicis-cucumerinum was evaluated. The new products are epoxidized polymers of polyvinylpyrrolidone (PVP) containing covalently bonded sorbic acid (polymeric esters of sorbic acid) and complexes of PVP with hydrogen bonded sorbic acid, characterized by controlled release of sorbic acid. It was shown that the polymeric complexes of sorbic acid with PVP were more effective fungicidal agents than sorbic acid polymeric esters. In all cases the activity of polymeric derivatives (esters and complexes) was increased by lowering the molecular weight of the polymeric carriers. Controlled release formulations of these polymeric derivatives are new promising products due to their low toxicity, wide range of efficient concentrations for application and ability to regulate lyophilicity. Our data contribute to the understanding of the action mechanism of various polymeric sorbic acid formulations and can result in products which are particularly suitable for food and feed protection applications.
Asunto(s)
Conservantes de Alimentos/farmacología , Fusarium/efectos de los fármacos , Micosis/prevención & control , Ácido Sórbico/farmacología , Preparaciones de Acción Retardada , Conservantes de Alimentos/química , Micosis/microbiología , Enfermedades de las Plantas/microbiología , Ácido Sórbico/química , Verduras/microbiologíaRESUMEN
This study describes the elimination of zearalenone concentrations in vitro using two new polymeric forms of cross-linked polyvinylpyrrolidone (cryogels of cross-linked PVP). Adsorption of zearalenone was studied under isothermal conditions and simulating pH of intestinal environment. A Freundlich isotherm was used to describe the adsorption data obtained. The results showed significant decrease of zearalenone concentrations, ranging from 33.5-66.2% per 25 mg of polymer. Adsorption capacity (k) was estimated to be higher than that of previously tested adsorbents, including crospovidone. The data indicate the need to investigate structure peculiarities in order to improve mycotoxin deactivation procedures using PVP derivatives.
Asunto(s)
Estrógenos no Esteroides/metabolismo , Micotoxinas/metabolismo , Zearalenona/metabolismo , Adsorción , Contaminación de Alimentos/prevención & control , Excipientes Farmacéuticos/química , Povidona/químicaRESUMEN
Newly synthesized amphiphilic polyacrylamide and poly(vinyl pyrrolidone), single terminus-modified with long-chain fatty acyl groups, are able to incorporate into the liposomal membrane, and similar to poly(ethylene glycol) prolong liposome circulation in vivo and decrease liposome accumulation in the liver. Protective efficacy of modified polymers increases with the increase in the length of acyl moiety and decreases for higher molecular weight polymers. The data on amphiphilic polymer-modified liposome biodistribution are presented.