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1.
Mol Pharm ; 13(12): 4168-4178, 2016 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-27934478

RESUMEN

Surfactant protein A (SP-A), a lung anti-infective protein, is a lectin with affinity for sugars found on fungal and micrococcal surfaces such as mannose. We synthesized a mannosylated poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) copolymer and used it to produce nanoparticles with a polyester (PLGA/PLA) core and a PEG shell decorated with mannose residues, designed to be strongly associated with SP-A for an increased uptake by alveolar macrophages. Nanoparticles made of the copolymers were obtained by nanoprecipitation and displayed a size of around 140 nm. The presence of mannose on the surface was demonstrated by zeta potential changes according to pH and by a strong aggregation in the presence of concanavalin A. Mannosylated nanoparticles bound to SP-A as demonstrated by dynamic light scattering and transmission electron microscopy. The association with SP-A increased nanoparticle uptake by THP-1 macrophages in vitro. In vivo experiments demonstrated that after intratracheal administration of nanoparticles with or without SP-A, SP-A-coated mannosylated nanoparticles were internalized by alveolar macrophages in greater proportion than SP-A-coated nonmannosylated nanoparticles. The data demonstrate for the first time that the pool of nanoparticles available to lung cells can be changed after surface modification, using a biomimetic approach.


Asunto(s)
Macrófagos Alveolares/metabolismo , Nanopartículas/química , Polímeros/química , Proteína A Asociada a Surfactante Pulmonar/metabolismo , Animales , Células Cultivadas , Femenino , Humanos , Macrófagos Alveolares/citología , Ratones , Ratones Endogámicos BALB C , Nanopartículas/administración & dosificación , Polímeros/administración & dosificación , Propiedades de Superficie
2.
Bioconjug Chem ; 26(7): 1307-13, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25343502

RESUMEN

CD44 receptor protein is found to be overexpressed by many tumors and is identified as one of the most common cancer stem cell surface markers including tumors affecting colon, breast, pancreas, and head and neck, making this an attractive receptor for therapeutic targeting. In this study, 2'-F-pyrimidine-containing RNA aptamer (Apt1), previously selected against CD44, was successfully conjugated to the surface of PEGylated liposomes using the thiol-maleimide click reaction. The conjugation of Apt1 to the surface of liposomes was confirmed by the change in size and zeta potential and by migration on agarose gel electrophoresis. The binding affinity of Apt1 was improved after conjugation compared to free-Apt1. The cellular uptake for Apt1-Lip was tested by flow cytometry and confocal imaging using the two CD44(+) cell lines, human lung cancer cells (A549) and human breast cancer cells (MDA-MB-231), and the CD44(-) cell line, mouse embryonic fibroblast cells (NIH/3T3). The results showed higher sensitivity and selectivity for Apt1-Lip compared to the blank liposomes (Mal-Lip). In conclusion, we demonstrate a successful conjugation of anti-CD44 aptamer to the surface of liposome and binding preference of Apt1-Lip to CD44-expressing cancer cells and conclude to a promising potency of Apt1-Lip as a specific drug delivery system.


Asunto(s)
Aptámeros de Nucleótidos/metabolismo , Receptores de Hialuranos/metabolismo , Liposomas/metabolismo , Neoplasias/metabolismo , Animales , Aptámeros de Nucleótidos/química , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Humanos , Liposomas/química , Ratones , Células 3T3 NIH , Neoplasias/tratamiento farmacológico
3.
Langmuir ; 31(41): 11186-94, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26375384

RESUMEN

The dynamics of the formation of siRNA-lipoplexes coated with hyaluronic acid (HA) and the parameters influencing their supramolecular organization were studied. The insertion of a HA-dioleylphosphatidylethanolamine (DOPE) conjugate in the liposome structure as well as subsequent complexation with siRNA increased the liposome size. Lipoplexes were around 110 nm at high ± charge ratios with a zeta potential around +50 mV and around 230 nm at low ± ratios, with a zeta potential that decreased to negative values, reaching -45 mV. The addition of the conjugate did not compromise siRNA binding to liposomes, although these nucleic acids induced a displacement of part of the HA-DOPE conjugate upon lipoplex formation, as confirmed by capillary electrophoresis. Isothermal titration calorimetry, X-ray diffraction studies, and cryo-TEM microscopy demonstrated that in addition to electrostatic interactions with siRNA a rearrangement of the lipid bilayers takes place, resulting in condensed oligolamellar vesicles. This phenomenon is dependent on the number of siRNA molecules and the degree of modification with HA. Finally, the suitable positioning of HA on the lipoplex surface and its ability to bind specifically to the CD44 receptors in a concentration-dependent manner was demonstrated by surface plasmon resonance analysis.


Asunto(s)
Sistemas de Liberación de Medicamentos , Receptores de Hialuranos/química , Ácido Hialurónico/química , Membrana Dobles de Lípidos/química , ARN Interferente Pequeño/química , Sitios de Unión , Humanos , Resonancia por Plasmón de Superficie
4.
Biomed Microdevices ; 16(2): 277-85, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24337430

RESUMEN

We describe a compartmentalized microdevice specifically designed to perform permeability studies across a model of lung barrier. Epithelial cell barriers were reproduced by culturing Calu-3 cells at the air-liquid interface (AIC) in 1 mm² microwells made from a perforated glass slide with an embedded porous membrane. We created a single basolateral reservoir for all microwells which eliminated the need to renew the growth medium during the culture growth phase. To perform drug permeability studies on confluent cell layers, the cell culture slide was aligned and joined to a collection platform consisting in 35 µL collection reservoirs connected at the top and bottom with microchannels. The integrity and functionality of the cell barriers were demonstrated by measurement of trans-epithelial electrical resistance (TEER), confocal imaging and permeability assays of ¹4C-sucrose. Micro-cell barriers were able to form confluent layers in 1 week, demonstrating a similar bioelectrical evolution as the Transwell systems used as controls. Tight junctions were observed throughout the cell-cell interfaces, and the low permeability coefficients of ¹4C-sucrose confirmed their functional presence, creating a primary barrier to the diffusion of solutes. This microdevice could facilitate the monitoring of biomolecule transport and the screening of formulations promoting their passage across the pulmonary barrier, in order to select candidates for pulmonary administration to patients.


Asunto(s)
Barrera Alveolocapilar/metabolismo , Técnicas de Cultivo de Célula , Técnicas Analíticas Microfluídicas , Sacarosa/farmacocinética , Edulcorantes/farmacocinética , Barrera Alveolocapilar/citología , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Línea Celular , Impedancia Eléctrica , Humanos , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Permeabilidad
5.
Int J Pharm ; 650: 123491, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-37806508

RESUMEN

The development of novel cell-based therapies has increased the necessity to improve the long-term storage of cells. The current method of cryopreservation is far from optimal, causing ice-associated mechanical and osmotic damage to sensitive cells. Cell encapsulation is emerging as a new strategy to overcome those current limitations; however, few data are applicable to slow freezing, with conflicting results and multiple experimental conditions. The objective of this research work was to evaluate the impact of capsule size and encapsulation method on cell survival and functionality after a conventional freezing protocol. To this end, cells were encapsulated in alginate beads of different sizes, spanning the range of 200-2000 µm thanks to multiple extrusion techniques and conditions, and further cryopreserved using a slow cooling rate (-1°C/min) and 10 % DMSO as cryoprotectant. Our data show that there is a strong correlation between bead size and cell survival after a slow cooling cryopreservation process, with cell viabilities ranging from 7 to 70 % depending on the capsule size, with the smallest capsules (230 µm) achieving the highest level of survival. The obtained results indicate that the beads' diameter, rather than their morphology or the technique used, plays a significant role in the post-thawing cell survival and functionality. These results show that a fine control of cell encapsulation in alginate hydrogels is required when it comes to overcoming the current limitations of long-term preservation techniques by slow cooling.


Asunto(s)
Dimetilsulfóxido , Hidrogeles , Supervivencia Celular , Criopreservación/métodos , Crioprotectores/farmacología , Alginatos , Macrófagos
6.
Drug Deliv Transl Res ; 14(8): 2146-2157, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38822092

RESUMEN

While long-acting injectable treatments are gaining increasing interest in managing chronic diseases, the available drug delivery systems almost exclusively rely on hydrophobic matrixes, limiting their application to either hydrophobic drugs or large and hydrophilic molecules such as peptides. To address the technological lock for long-acting delivery systems tailored to small, hydrophilic drugs such as anticancer and antiviral nucleoside/nucleotide analogues, we have synthesized and characterized an original approach with a multi-scale structure: (i) a nucleotide (adenosine triphosphate, ATP) is first incorporated in hydrophilic chitosan-Fe(III) nanogels; (ii) these nanogels are then transferred by freeze-drying and resuspension into a water-free, hydrophobic medium containing PLGA and an organic solvent, N-methyl-2-pyrrolidone. We show that this specific association allows an injectable and homogeneous dispersion, able to form in situ implants upon injection in physiological or aqueous environments. This system releases ATP in vitro without any burst effect in a two-step mechanism, first as nanogels acting as an intermediate reservoir over a week, then as free drug over several weeks. In vivo studies confirmed the potential of such nanostructured implants for sustained drug release following subcutaneous injection to mice hock, opening perspectives for sustained and targeted delivery through the lymphatic system.


Asunto(s)
Adenosina Trifosfato , Quitosano , Interacciones Hidrofóbicas e Hidrofílicas , Nanoestructuras , Animales , Adenosina Trifosfato/administración & dosificación , Quitosano/química , Quitosano/administración & dosificación , Nanoestructuras/administración & dosificación , Nanoestructuras/química , Liberación de Fármacos , Ratones , Preparaciones de Acción Retardada/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Sistemas de Liberación de Medicamentos , Implantes de Medicamentos , Inyecciones Subcutáneas , Nanogeles/química , Polietilenglicoles/química , Polietilenglicoles/administración & dosificación , Pirrolidinonas
7.
Biomacromolecules ; 14(3): 737-42, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23351139

RESUMEN

The natural nucleotide adenosine triphosphate (ATP) and nucleotide analogues such as azidothymidine triphosphate (AZT-TP) display important pharmacological activities for the treatment of ischemia and HIV infections, respectively. Their clinical use is, however, limited mostly due to their hydrophilicity, which highly restricts their diffusion into the target cells. Few nanocarriers have been proposed to address the challenge of ATP/AZT-TP cellular delivery, but the loading efficiency, preparation complexity, and efficient cellular delivery remain important barriers to their development. In this study, we propose an original, straightforward and versatile design of nucleotide and nucleotide analogue nanocarriers based on the natural polysaccharide chitosan (CS). We show that the drugs ATP and AZT-TP can induce ionotropic gelation of CS, leading to CS/ATP and CS/AZT-TP nanoparticles with high drug entrapment efficiency and loading rate-up to 44%. Such nanocarriers release ATP and AZT-TP in physiological media and allow an efficient in vitro cellular delivery of these molecules down to the cell cytoplasm.


Asunto(s)
Adenosina Trifosfato/farmacología , Didesoxinucleótidos/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Nucleótidos/química , Zidovudina/análogos & derivados , Adenosina Trifosfato/química , Animales , Supervivencia Celular , Quitosano/química , Didesoxinucleótidos/química , Infecciones por VIH/tratamiento farmacológico , Macrófagos/metabolismo , Ratones , Zidovudina/química , Zidovudina/farmacología
8.
Adv Mater ; 35(13): e2209615, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36649533

RESUMEN

Pulmonary exposure to some engineered nanomaterials can cause chronic lesions as a result of unresolved inflammation. Among 2D nanomaterials and graphene, MoS2 has received tremendous attention in optoelectronics and nanomedicine. Here an integrated approach is proposed to follow up the transformation of MoS2 nanosheets at the nanoscale and assesss their impact on lung inflammation status over 1 month after a single inhalation in mice. Analysis of immune cells, alveolar macrophages, extracellular vesicles, and cytokine profiling in bronchoalveolar lavage fluid (BALF) shows that MoS2 nanosheets induced initiation of lung inflammation. However, the inflammation is rapidly resolved despite the persistence of various biotransformed molybdenum-based nanostructures in the alveolar macrophages and the extracellular vesicles for up to 1 month. Using in situ liquid phase transmission electron microscopy experiments, the dynamics of MoS2 nanosheets transformation triggered by reactive oxygen species could be evidenced. Three main transformation mechanisms are observed directly at the nanoscale level: 1) scrolling of the dispersed sheets leading to the formation of nanoscrolls and folded patches, 2) etching releasing soluble MoO4 - , and 3) oxidation generating oxidized sheet fragments. Extracellular vesicles released in BALF are also identified as a potential shuttle of MoS2 nanostructures and their degradation products and more importantly as mediators of inflammation resolution.


Asunto(s)
Vesículas Extracelulares , Neumonía , Animales , Ratones , Molibdeno/química , Disulfuros/química , Inflamación/inducido químicamente
9.
Int J Pharm ; 626: 122131, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36028084

RESUMEN

A common approach to tackle the poor intestinal membrane permeability of peptides after oral administration is to formulate them with a permeation enhancer (PE). Increased oral bioavailability for oral peptide candidates has been reported from clinical trials when either salcaprozate sodium (SNAC) or sodium caprate (C10) is incorporated in the formulation. However, little is known about how they physically interact with peptides in solution. Our objective was to compare the biophysical interactions between the GLP-1 analogue exenatide (Byetta®, Lilly), and C10 or SNAC using a variety of advanced analytical techniques. First, critical micelle concentration was measured in different buffers for both PEs. Dynamic light scattering (DLS) measurements revealed specific supramolecular structures arising from exenatide-PE association. Surface plasmon resonance (SPR) indicated the formation of exenatide-PE complexes with a high contribution from non-specific interactions and rapid binding kinetics, resulting in overall low affinities. DLS and isothermal titration calorimetry (ITC) were used to examine the supramolecular organization of the PEs, and revealed thermodynamic signatures characterized by unfavourable enthalpic contributions compensated by favourable entropic ones, but with low-affinity estimates in water (KD in the 10-100 µM range). With affinity capillary electrophoresis (ACE), weak interactions between exenatide and SNAC or C10 were confirmed in saline, with a dissociation constant around 10 µM and 30 µM respectively. In biorelevant intestinal media, the bile salts in FaSSIF and FeSSIF further reduced the binding of both agents to exenatide (KD ≈ 100 µM), indicating that the interaction between the PEs and exenatide might be inhibited by bile salts in the GI lumen. This study suggests that the interactions of both PEs with exenatide follow a similar non-covalent mechanism and are of low affinity.


Asunto(s)
Absorción Intestinal , Micelas , Ácidos y Sales Biliares , Caprilatos , Ácidos Decanoicos , Exenatida , Péptido 1 Similar al Glucagón , Péptidos , Agua
10.
Biomacromolecules ; 12(11): 4136-43, 2011 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-21981120

RESUMEN

Despite the wide interest raised by lung administration of nanoparticles (NPs) for the treatment of various diseases, little information is available on their effect toward the airway epithelial barrier function. In this study, the potential damage of the pulmonary epithelium upon exposure to poly(lactide-co-glycolide) (PLGA) NPs has been assessed in vitro using a Calu-3-based model of the bronchial epithelial barrier. Positively and negatively charged as well as neutral PLGA NPs were obtained by coating their surface with chitosan (CS), poloxamer (PF68), or poly(vinyl alcohol) (PVA). The role of NP surface chemistry and charge on the epithelial resistance and mucus turnover, using MUC5AC as a marker, was investigated. The interaction with mucin reduced the penetration of CS- and PVA-coated NPs, while the hydrophilic PF68-coated NPs diffused across the mucus barrier leading to a higher intracellular accumulation. Only CS-coated NPs caused a transient but reversible decrease of the trans-epithelial electrical resistance (TEER). None of the NP formulations increased MUC5AC mRNA expression or the protein levels. These in vitro results highlight the safety of PLGA NPs toward the integrity and function of the bronchial airway barrier and demonstrate the crucial role of NP surface properties to achieve a controlled and sustained delivery of drugs via the pulmonary route.


Asunto(s)
Bronquios/citología , Células Epiteliales/metabolismo , Ácido Láctico/farmacología , Moco/metabolismo , Nanopartículas , Ácido Poliglicólico/farmacología , Línea Celular , Impedancia Eléctrica , Células Epiteliales/fisiología , Expresión Génica/efectos de los fármacos , Humanos , Ácido Láctico/metabolismo , Mucina 5AC/genética , Mucina 5AC/metabolismo , Permeabilidad , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Propiedades de Superficie
11.
Int J Pharm ; 610: 121213, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34678397

RESUMEN

(R)-CE3F4, a specific inhibitor of EPAC1 (exchange protein directly activated by cAMP type 1), has been demonstrated in vitro and in vivo to reduce hypertrophic signaling contributing to heart failure or to control arrhythmia and has shown promise as a drug candidate. However, (R)-CE3F4 exhibits poor solubility in aqueous media and has shown sensitivity to enzyme hydrolysis in plasma. To overcome these issues, the drug was entrapped in liposomes and lipid nanocapsules. Both systems considerably increased the drug apparent solubility in aqueous media. Among these nanocarriers, lipid nanocapsules offered significant protection in vitro against enzymatic degradation by increasing the (R)-CE3F4 apparent half-life from around 40 min to 6 h. Pharmacokinetics and biodistribution of (R)-CE3F4 radiolabeled or not were studied in healthy C57BL/6 mice. The non-encapsulated 3H-CE3F4 showed a very rapid distribution outside the blood compartment. Similar results were observed when using nanocarriers together with a fast dissociation of 3H-CE3F4 from nanocapsules simultaneously labeled with 14C. Thus, essential preclinical information on CE3F4 fate has been obtained, as well as the impact of its formulation using lipid-based nanocarriers.


Asunto(s)
Nanocápsulas , Animales , Lípidos , Liposomas , Ratones , Ratones Endogámicos C57BL , Distribución Tisular
12.
Artículo en Inglés | MEDLINE | ID: mdl-34666890

RESUMEN

The CE3F4 is an inhibitor of the type 1 exchange protein directly activated by cAMP (EPAC1), which is involved in numerous signaling pathways. The inhibition of EPAC1 shows promising results in vitro and in vivo in different cardiac pathological situations like hypertrophic signaling, contributing to heart failure, or arrhythmia. An HPLC-UV method with a simple and fast sample treatment allowed the quantification of (R)-CE3F4. Sample treatment consisted of simple protein precipitation with 50 µL of ethanol and 150 µL of acetonitrile for a 50 µL biological sample. Two wavelengths were used according to the origin of plasma (220 or 250 nm for human samples and 250 nm for murine samples). Accuracy profile was evaluated for both wavelengths, and the method was in agreement with the criteria given by the EMA in the guideline for bioanalytical method validation for human and mouse plasma samples. The run time was 12 min allowing the detection of the (R)-CE3F4 and a metabolite. This study further permitted understanding the behavior of CE3F4 in plasma by highlighting an important difference between humans and rodents on plasma metabolism and may impact future in vivo studies related to this molecule and translation of results between animal models and humans. Using paraoxon as a metabolism inhibitor was crucial for the stabilization of (R)-CE3F4 in murine samples. HPLC-UV and HPLC-MS/MS studies were conducted to confirm metabolite structure and consequently, the main metabolic pathway in murine plasma.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Quinolinas/sangre , Quinolinas/química , Animales , Recolección de Muestras de Sangre , Humanos , Límite de Detección , Modelos Lineales , Ratones , Paraoxon/química , Reproducibilidad de los Resultados
13.
Pharmaceutics ; 13(1)2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33477667

RESUMEN

Oral lichen planus (OLP) is an ongoing and chronic inflammatory disease affecting the mucous membrane of the oral cavity. Currently, the treatment of choice consists in the direct application into the buccal cavity of semisolid formulations containing a corticosteroid molecule to decrease inflammatory signs and symptoms. However, this administration route has shown various disadvantages limiting its clinical use and efficacy. Indeed, the frequency of application and the incorrect use of the preparation may lead to a poor efficacy and limit the treatment compliance. Furthermore, the saliva clearance and the mechanical stress present in the buccal cavity also involve a decrease in the mucosal exposure to the drug. In this context, the design of a new pharmaceutical formulation, containing a steroidal anti-inflammatory, mucoadhesive, sprayable and exhibiting a sustained and controlled release seems to be suitable to overcome the main limitations of the existing pharmaceutical dosage forms. The present work reports the formulation, optimization and evaluation of the mucoadhesive and release properties of a poloxamer 407 thermosensitive hydrogel containing a poorly water-soluble corticosteroid, dexamethasone acetate (DMA), threaded into hydroxypropyl-beta-cyclodextrin (HP-ß-CD) molecules. Firstly, physicochemical properties were assessed to ensure suitable complexation of DMA into HP-ß-CD cavities. Then, rheological properties, in the presence and absence of various mucoadhesive agents, were determined and optimized. The hydration ratio (0.218-0.191), the poloxamer 407 (15-17 wt%) percentage and liquid-cyclodextrin state were optimized as a function of the gelation transition temperature, viscoelastic behavior and dynamic flow viscosity. Deformation and resistance properties were evaluated in the presence of various mucoadhesive compounds, being the sodium alginate and xanthan gum the most suitable to improve adhesion and mucoadhesion properties. Xanthan gum was shown as the best agent prolonging the hydrogel retention time up to 45 min. Furthermore, xanthan gum has been found as a relevant polymer matrix controlling drug release by diffusion and swelling processes in order to achieve therapeutic concentration for prolonged periods of time.

14.
Cell Mol Life Sci ; 66(17): 2873-96, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19499185

RESUMEN

Nanocarriers offer unique possibilities to overcome cellular barriers in order to improve the delivery of various drugs and drug candidates, including the promising therapeutic biomacromolecules (i.e., nucleic acids, proteins). There are various mechanisms of nanocarrier cell internalization that are dramatically influenced by nanoparticles' physicochemical properties. Depending on the cellular uptake and intracellular trafficking, different pharmacological applications may be considered. This review will discuss these opportunities, starting with the phagocytosis pathway, which, being increasingly well characterized and understood, has allowed several successes in the treatment of certain cancers and infectious diseases. On the other hand, the non-phagocytic pathways encompass various complicated mechanisms, such as clathrin-mediated endocytosis, caveolae-mediated endocytosis and macropinocytosis, which are more challenging to control for pharmaceutical drug delivery applications. Nevertheless, various strategies are being actively investigated in order to tailor nanocarriers able to deliver anticancer agents, nucleic acids, proteins and peptides for therapeutic applications by these non-phagocytic routes.


Asunto(s)
Sistemas de Liberación de Medicamentos , Endocitosis/fisiología , Nanopartículas , Animales , Clatrina/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Humanos , Liposomas/química , Liposomas/metabolismo , Nanopartículas/química , Tamaño de la Partícula , Fagocitosis/fisiología , Propiedades de Superficie
15.
Nanoscale ; 12(4): 2452-2463, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31915784

RESUMEN

The understanding of the cellular uptake and the intracellular fate of nanoparticles and their subsequent influence on cell viability is challenging as far as micelles are concerned. Such systems are dynamic by nature, existing as unimers under their critical micelle concentration (CMC), and as micelles in equilibrium with unimers above the CMC, making canonical dose-response relationships difficult to establish. The purpose of this study was to investigate the in vitro cytotoxicity and uptake of two micellar sytems that are relevant for drug delivery. The two micelles incorporate a poly(ethylene glycol) coating and a pentacosadiynoic core which is either polymerized (pDA-PEG micelles) or non-polymerized (DA-PEG micelles), with the aim of evaluating the influence of the micelles status ("particle-like" or "dynamic", respectively) on their toxicological profile. Intracellular distribution and cytotoxicity of polymerized and non-polymerized micelles were investigated on RAW 264.7 macrophages in order to compare any different interactions with cells. Non-polymerized micelles showed significantly higher cytotoxicity than polymerized micelles, especially in terms of cell permeabilization, correlated to a higher accumulation in cell membranes. Other potential toxicity endpoints of polymerized micelles were then thoroughly studied in order to assess possible responses resulting from their endocytosis. No specific mechanisms of cytotoxicity were observed, neither in terms of apoptosis induction, cell membrane damage, release of inflammatory mediators nor genotoxicity. These data indicate that non-polymerized micelles accumulate in the cell membrane and induce cell membrane permeabilization, resulting in significant toxicity, whereas polymerized, stable micelles are internalized by cells but exert no or very low toxicity.


Asunto(s)
Micelas , Polímero Poliacetilénico/toxicidad , Animales , Apoptosis , Portadores de Fármacos , Endocitosis , Inflamación , L-Lactato Deshidrogenasa/metabolismo , Lipopolisacáridos , Ratones , Mitocondrias/metabolismo , Nanopartículas/química , Nanopartículas/toxicidad , Nanoestructuras , Necrosis , Permeabilidad , Polímero Poliacetilénico/química , Polietilenglicoles/química , Polimerizacion , Células RAW 264.7
16.
Biomacromolecules ; 9(10): 2881-90, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18788777

RESUMEN

Specific siRNAs that target estrogen receptor alpha (ERalpha) were encapsulated in nanocapsules (NCs). We produced small (approximately 100-200 nm) ERalpha-siRNA NCs with a water core by incorporating two mixed duplexes of specific ERalpha-siRNAs (ERalpha-mix-siRNA) into NCs. The encapsulation yield that was obtained with poly(iso-butylcyanoacrylate) (PIBCA) NCs was low, whereas no release of trapped siRNA was observed for poly(ethylene)glycol-poly(D,L-lactide-co-glycolide) (PEG-PLGA) NCs. High levels of ERalpha-siRNA incorporation into PEG-epsilon-caprolactone-malic acid (PEG-PCL/MA) NCs (3.3 microM in a polymer solution at 16 mg/mL) were observed (72% yield). No difference in size or zeta potential was observed between siRNA NCs that were based on PEG-PCL/MA and empty NCs. Fluorescence quenching assays confirmed the incorporation of siRNA into the NC core. A persistent loss of ERalpha (90% over 5 days) was observed in MCF-7 human breast cancer cells that were exposed to PEG-PCL/MA NCs that were loaded with ERalpha-siRNA. The intravenous injection of these NCs into estradiol-stimulated MCF-7 cell xenografts led to a significant decrease in tumor growth and a decrease in ERalpha expression in tumor cells. These data indicate that a novel strategy, based on ERalpha-siRNA delivery, could be developed for the treatment of hormone-dependent breast cancers.


Asunto(s)
Materiales Biocompatibles/química , Química Física/métodos , Receptor alfa de Estrógeno/metabolismo , ARN Interferente Pequeño/metabolismo , Animales , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Emulsiones , Femenino , Humanos , Ensayo de Materiales , Ratones , Ratones Desnudos , Nanocápsulas/química , Trasplante de Neoplasias
17.
Adv Drug Deliv Rev ; 134: 122-137, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30267743

RESUMEN

Aptamers are versatile nucleic acid-based macromolecules characterized by their high affinity and specificity to a specific target. Taking advantage of such binding properties, several aptamers have been selected to bind tumor biomarkers and have been used as targeting ligands for the functionalization of nanomedicines. Different functionalization methods have been used to link aptamers to the surface drug nanocarriers. The pre-clinical data of such nanomedicines overall show an enhanced and selective delivery of therapeutic payloads to cancer cells, thereby accelerating steps towards more effective therapeutic systems. This review describes the current advances in the use of aptamers as targeting moieties for the delivery of therapeutic and imaging agents to tumors by conjugation to organic and inorganic nanocarriers.


Asunto(s)
Antineoplásicos/uso terapéutico , Aptámeros de Nucleótidos/química , Sistemas de Liberación de Medicamentos , Nanomedicina , Neoplasias/tratamiento farmacológico , Portadores de Fármacos/química , Humanos , Ligandos , Nanopartículas/química , Neoplasias/patología
18.
J Control Release ; 271: 98-106, 2018 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-29277682

RESUMEN

In this study, we describe a liposome-based siRNA delivery system with a core composed of siRNA:protamine complex and a shell designed for the active targeting of CD44-expressing cells using for the first time the anti-CD44 aptamer (named Apt1) as targeting ligand. Among all functions, CD44 is the most common cancer stem cell surface biomarker and is found overexpressed in many tumors making this an attractive receptor for therapeutic targeting. This unique non-cationic system was evaluated for the silencing of the reporter gene of luciferase (luc2) in a triple-negative breast cancer model in vitro and in vivo. We show the possibility of conjugating an aptamer to siRNA-containing liposomes for an efficient gene silencing in CD44-expressing tumor cells in vivo, in the perspective of silencing disease-related genes in tumors.


Asunto(s)
Aptámeros de Nucleótidos/administración & dosificación , Biomarcadores de Tumor/genética , Receptores de Hialuranos/genética , ARN Interferente Pequeño/administración & dosificación , Neoplasias de la Mama Triple Negativas/genética , Animales , Línea Celular Tumoral , Femenino , Silenciador del Gen , Humanos , Liposomas , Luciferasas/genética , Ratones , Nanomedicina , Neoplasias de la Mama Triple Negativas/terapia
20.
Int J Pharm ; 525(1): 203-210, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28438698

RESUMEN

Aiming at improving the nebulization performances and lung antioxidant protection of curcumin, chitosan or hyaluronan-coated liposomes were prepared and their characteristics and performances were compared with that of uncoated liposomes. Curcumin loaded liposomes displayed a diameter lower than 100nm, the coating with both polymers led to a small increase of vesicle size around 130nm and the zeta potential turned to positive values using chitosan while remained negative using hyaluronan. Chitosan allowed the formation of more lamellar and stiffer vesicles with a higher bilayer thickness (dB∼59Ǻ) with respect to the uncoated liposomes, whereas hyaluronan allowed the interdigitation of the bilayers (dB∼47Ǻ) due to the polymer intercalation between phospholipid head groups resulting in vesicles mainly organized in uncorrelated bilayers. Both polymer coatings, especially hyaluronan, greatly improved the stability of the vesicles, especially during the nebulization process, promoting the deposition of the phytodrug in the furthest stages of the impactor in high amount (≥50%). Polymer coated vesicles were biocompatible and improved the curcumin ability to protect A549 cells from the oxidative stress induced by hydrogen peroxide, restoring healthy conditions (cell relative metabolic activity 100%). In particular, a synergic effect of curcumin and hyaluronan was observed resulting in a proliferative effect and a subsequent further enhancement of cell relative metabolic activity up to 120%.


Asunto(s)
Quitosano/química , Curcumina/administración & dosificación , Portadores de Fármacos/química , Ácido Hialurónico/química , Liposomas/química , Células A549 , Humanos , Pulmón/efectos de los fármacos , Polímeros
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