RESUMO
The phosphorylation of (+) alpha tocopherol produces adhesive nanostructures that interact with oral biofilms to restrict their growth. The aim of this work was to understand if these adhesive (+) alpha tocopheryl phosphate (α-TP) nanostructures could also control macrophage responses to the presence of oral bacteria. The (+) α-TP planar bilayer fragments (175â¯nm⯱â¯21â¯nm) formed in a Trizma®/ethanol vehicle swelled when exposed to the cell lines (maximum stabilized sizeâ¯=â¯29⯵m). The swelled (+) α-TP aggregates showed selective toxicity towards THP-1 macrophages (LD50â¯=â¯304⯵M) compared to human gingival fibroblasts (HGF-1 cells; LD50â¯>â¯5â¯mM), and they inhibited heat killed bacteria stimulated MCP-1 production in both macrophages (control 57.3⯱â¯18.1â¯pg/mL vs (+) α-TP 6.5⯱â¯3.2â¯pg/mL) and HGF-1 cells (control 673.5⯱â¯133â¯pg/mL vs (+) α-TP - 463.9⯱â¯68.9â¯pg/mL).
Assuntos
Macrófagos/efeitos dos fármacos , Boca/efeitos dos fármacos , Nanoestruturas/administração & dosagem , alfa-Tocoferol/análogos & derivados , Biofilmes/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Quimiocina CCL2/genética , Gengiva/efeitos dos fármacos , Gengiva/crescimento & desenvolvimento , Gengiva/microbiologia , Gengiva/patologia , Fator de Crescimento de Hepatócito/genética , Humanos , Macrófagos/metabolismo , Macrófagos/microbiologia , Monócitos/efeitos dos fármacos , Monócitos/microbiologia , Boca/crescimento & desenvolvimento , Boca/microbiologia , Boca/patologia , Nanoestruturas/química , Fosforilação/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , alfa-Tocoferol/química , alfa-Tocoferol/farmacologiaRESUMO
Atherosclerosis, the build-up of occlusive, lipid-rich plaques in arterial walls, is a focal trigger of chronic coronary, intracranial, and peripheral arterial diseases, which together account for the leading causes of death worldwide. Although the directed treatment of atherosclerotic plaques remains elusive, macrophages are a natural target for new interventions because they are recruited to lipid-rich lesions, actively internalize modified lipids, and convert to foam cells with diseased phenotypes. In this work, we present a nanomedicine platform to counteract plaque development based on two building blocks: first, at the single macrophage level, sugar-based amphiphilic macromolecules (AMs) were designed to competitively block oxidized lipid uptake via scavenger receptors on macrophages; second, for sustained lesion-level intervention, AMs were fabricated into serum-stable core/shell nanoparticles (NPs) to rapidly associate with plaques and inhibit disease progression in vivo. An AM library was designed and fabricated into NP compositions that showed high binding and down-regulation of both MSR1 and CD36 scavenger receptors, yielding minimal accumulation of oxidized lipids. When intravenously administered to a mouse model of cardiovascular disease, these AM NPs showed a pronounced increase in lesion association compared with the control nanoparticles, causing a significant reduction in neointimal hyperplasia, lipid burden, cholesterol clefts, and overall plaque occlusion. Thus, synthetic macromolecules configured as NPs are not only effectively mobilized to lipid-rich lesions but can also be deployed to counteract atheroinflammatory vascular diseases, highlighting the promise of nanomedicines for hyperlipidemic and metabolic syndromes.
Assuntos
Aterosclerose/tratamento farmacológico , Carboidratos , Macrófagos/metabolismo , Nanopartículas , Placa Aterosclerótica/tratamento farmacológico , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Antígenos CD36/genética , Antígenos CD36/metabolismo , Humanos , Hiperplasia/genética , Hiperplasia/metabolismo , Hiperplasia/patologia , Lipídeos , Macrófagos/patologia , Camundongos , Camundongos Knockout , Neointima/genética , Neointima/metabolismo , Neointima/patologia , Oxirredução , Placa Aterosclerótica/sangue , Placa Aterosclerótica/genética , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Receptores Depuradores Classe A/genética , Receptores Depuradores Classe A/metabolismoRESUMO
PURPOSE: For the rational design of nanovaccines against respiratory pathogens, careful selection of optimal particle size and chemistry is paramount. This work investigates the impact of these properties on the deposition, biodistribution, and cellular interactions of nanoparticles within the lungs. METHOD: In this work, biodegradable poly(sebacic anhydride) (poly(SA)) nanoparticles of multiple sizes were synthesized with narrow particle size distributions. The lung deposition and retention as well as the internalization by phagocytic cells of these particles were compared to that of non-degradable monodisperse polystyrene nanoparticles of similar sizes. RESULTS: The initial deposition of intranasally administered particles in the lungs was dependent on primary particle size, with maximal deposition occurring for the 360-470 nm particles, regardless of chemistry. Over time, both particle size and chemistry affected the frequency of particle-positive cells and the specific cell types taking up particles. The biodegradable poly(SA) particles associated more closely with phagocytic cells and the dynamics of this association impacted the clearance of these particles from the lung. CONCLUSIONS: The findings reported herein indicate that both size and chemistry control the fate of intranasally administered particles and that the dynamics of particle association with phagocytic cells in the lungs provide important insights for the rational design of pulmonary vaccine delivery vehicles.
Assuntos
Anidridos/química , Anidridos/farmacocinética , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacocinética , Ácidos Decanoicos/química , Ácidos Decanoicos/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Pulmão/metabolismo , Vacinas/administração & dosagem , Administração Intranasal , Anidridos/síntese química , Animais , Materiais Biocompatíveis/síntese química , Ácidos Decanoicos/síntese química , Portadores de Fármacos/síntese química , Feminino , Pulmão/imunologia , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Fagócitos/imunologia , Fagócitos/metabolismo , Fagocitose , Propriedades de Superfície , Distribuição TecidualRESUMO
Atherosclerosis, an inflammatory lipid-rich plaque disease is perpetuated by the unregulated scavenger-receptor-mediated uptake of oxidized lipoproteins (oxLDL) in macrophages. Current treatments lack the ability to directly inhibit oxLDL accumulation and foam cell conversion within diseased arteries. In this work, we harness nanotechnology to design and fabricate a new class of nanoparticles (NPs) based on hydrophobic mucic acid cores and amphiphilic shells with the ability to inhibit the uncontrolled uptake of modified lipids in human macrophages. Our results indicate that tailored NP core and shell formulations repress oxLDL internalization via dual complementary mechanisms. Specifically, the most atheroprotective molecules in the NP cores competitively reduced NP-mediated uptake to scavenger receptor A (SRA) and also down-regulated the surface expression of SRA and CD36. Thus, nanoparticles can be designed to switch activated, lipid-scavenging macrophages to antiatherogenic phenotypes, which could be the basis for future antiatherosclerotic therapeutics.
Assuntos
Aterosclerose , Macrófagos/citologia , Nanopartículas/química , Receptores Depuradores Classe A/química , Arteriosclerose/metabolismo , Antígenos CD36/química , Regulação para Baixo , Células Espumosas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação , Leucócitos Mononucleares , Metabolismo dos Lipídeos/genética , Lipoproteínas/química , Lipoproteínas LDL/química , Macrófagos/efeitos dos fármacos , Nanotecnologia/métodos , Fenótipo , Placa AteroscleróticaRESUMO
Amphiphilic macromolecules (AMs) composed of sugar backbones modified with branched aliphatic chains and a poly(ethylene glycol) (PEG) tail can inhibit macrophage uptake of oxidized low-density lipoproteins (oxLDL), a major event underlying atherosclerosis development. Previous studies indicate that AM hydrophobic domains influence this bioactivity through interacting with macrophage scavenger receptors, which can contain basic and/or hydrophobic residues within their binding pockets. In this study, we compare two classes of AMs to investigate their ability to promote athero-protective potency via hydrogen-bonding or hydrophobic interactions with scavenger receptors. A series of ether-AMs, containing methoxy-terminated aliphatic arms capable of hydrogen-bonding, was synthesized. Compared to analogous AMs containing no ether moieties (alkyl-AMs), ether-AMs showed improved cytotoxicity profiles. Increasing AM hydrophobicity via incorporation of longer and/or alkyl-terminated hydrophobic chains yielded macromolecules with enhanced oxLDL uptake inhibition. These findings indicate that hydrophobic interactions and the length of AM aliphatic arms more significantly influence AM bioactivity than hydrogen-bonding.
Assuntos
Lipoproteínas LDL , Monócitos/metabolismo , Polietilenoglicóis , Receptores Depuradores , Aterosclerose , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipoproteínas LDL/química , Lipoproteínas LDL/metabolismo , Masculino , Monócitos/patologia , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Receptores Depuradores/química , Receptores Depuradores/metabolismoRESUMO
Atherosclerosis is a condition resulting from the accumulation of oxidized low-density lipoproteins (oxLDLs) in arterial walls. Previously developed macromolecules consisting of alkyl chains and polyethylene glycol (PEG) on a mucic acid backbone, termed nanolipoblockers (NLBs) are hypothesized to mitigate the uptake of oxLDL by macrophage scavenger receptors. In this work, we developed a coarse grained model to characterize the interactions between NLBs with a segment of human scavenger receptor A (SR-A), a key receptor domain that regulates cholesterol uptake and foam cell conversion of macrophages, and studied NLB ability to block oxLDL uptake in PBMC macrophages. We focused on four different NLB configurations with variable molecular charge, charge location, and degree of NLB micellization. Kinetic studies showed that three of the four NLBs form micelles within 300 ns and of sizes comparable to literature results. In the presence of SR-A, micelle-forming NLBs interacted with the receptor primarily in an aggregated state rather than as single unimers. The model showed that incorporation of an anionic charge near the NLB mucic acid head resulted in enhanced interaction with the proposed binding pocket of SR-A compared to uncharged NLBs. By contrast, NLBs with an anionic charge located at the PEG tail showed no interaction increase as NLB aggregates were predominately observed to interact away from the oxLDL binding site. Additionally, using two different methods to assess the number of contacts that each NLB type formed with SR-A, we found that the rank order of contacts coincided with our experimental flow cytometry results evaluating the ability of the different NLBs to block the uptake of oxLDL.
Assuntos
Antimetabólitos/farmacologia , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Simulação de Dinâmica Molecular , Polietilenoglicóis/farmacologia , Receptores Depuradores Classe A/química , Antimetabólitos/síntese química , Sítios de Ligação , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Humanos , Lipoproteínas LDL/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , Micelas , Conformação Molecular , Polietilenoglicóis/síntese química , Ligação Proteica , Receptores Depuradores Classe A/metabolismo , Açúcares Ácidos/síntese química , Açúcares Ácidos/farmacologiaRESUMO
Combinatorial methods have been developed to study the phase behavior of biodegradable polyanhydrides for drug delivery applications. The polyanhydrides of interest are poly[1,6-bis(p-carboxyphenoxy) hexane] (CPH) and poly[sebacic anhydride] (SA). Both continuous and discrete polymer blend libraries were fabricated by using a combination of solution-based gradient deposition and rapid prototyping. Blend compositions were characterized via a high throughput transmission Fourier transform infrared (FTIR) sampling technique and compared against theoretical mass balance predictions. To obtain phase diagrams of CPH/SA, the effect of blend composition and annealing temperature on the miscibility of the blend was studied. This gradient library was observed with optical microscopy in order to determine cloud points. These results were compared with a theoretical phase diagram obtained from Flory-Huggins theory and with atomic force microscopy (AFM) experiments on blend libraries and the agreement between the methods was very good. The high throughput method demonstrates that the CPH/SA system exhibits upper critical solution temperature behavior. These libraries are amenable to other high throughput applications in biomaterials science including cell viability, cell activation, and protein/biomaterial interactions.
Assuntos
Técnicas de Química Combinatória , Polianidridos/química , Sistemas de Liberação de Medicamentos , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Modelos Teóricos , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
BACKGROUND: The rational design of biodegradable polymeric devices for controlled drug delivery and tissue engineering is an important area of research for advancing new therapies for cancer, diabetes and immune-related disorders. In an era of escalating costs for discovery-based research, there is an urgent need to develop new and rapid methods to design drug delivery systems. OBJECTIVE/METHODS: By merging this field of study with rapid and high throughput methods of design, optimization and development, researchers have been able to accelerate the discovery and design processes for these devices. Combinatorial research enables the rapid identification of key regions of interest. CONCLUSION: This review focuses on the opportunities and challenges in the area of combinatorial biomaterials design for drug delivery, as there has been a great deal of significant progress over the past decade to propel this approach for the rational design of biomaterials.
Assuntos
Materiais Biocompatíveis/química , Técnicas de Química Combinatória/métodos , Sistemas de Liberação de Medicamentos , Animais , Descoberta de Drogas , Humanos , Projetos de PesquisaRESUMO
Enhanced bioactive anti-oxidant formulations are critical for treatment of inflammatory diseases, such as atherosclerosis. A hallmark of early atherosclerosis is the uptake of oxidized low density lipoprotein (oxLDL) by macrophages, which results in foam cell and plaque formation in the arterial wall. The hypolipidemic, anti-inflammatory, and antioxidative properties of polyphenol compounds make them attractive targets for treatment of atherosclerosis. However, high concentrations of antioxidants can reverse their anti-atheroprotective properties and cause oxidative stress within the artery. Here, we designed a new class of nanoparticles with anti-oxidant polymer cores and shells comprised of scavenger receptor targeting amphiphilic macromolecules (AMs). Specifically, we designed ferulic acid-based poly(anhydride-ester) nanoparticles to counteract the uptake of high levels of oxLDL and regulate reactive oxygen species generation (ROS) in human monocyte derived macrophages (HMDMs). Compared to all compositions examined, nanoparticles with core ferulic acid-based polymers linked by diglycolic acid (PFAG) showed the greatest inhibition of oxLDL uptake. At high oxLDL concentrations, the ferulic acid diacids and polymer nanoparticles displayed similar oxLDL uptake. Treatment with the PFAG nanoparticles downregulated the expression of macrophage scavenger receptors, CD-36, MSR-1, and LOX-1 by about 20-50%, one of the causal factors for the decrease in oxLDL uptake. The PFAG nanoparticle lowered ROS production by HMDMs, which is important for maintaining macrophage growth and prevention of apoptosis. Based on these results, we propose that ferulic acid-based poly(anhydride ester) nanoparticles may offer an integrative strategy for the localized passivation of the early stages of the atheroinflammatory cascade in cardiovascular disease. STATEMENT OF SIGNIFICANCE: Future development of anti-oxidant formulations for atherosclerosis applications is essential to deliver an efficacious dose while limiting localized concentrations of pro-oxidants. In this study, we illustrate the potential of degradable ferulic acid-based polymer nanoparticles to control macrophage foam cell formation by significantly reducing oxLDL uptake through downregulation of scavenger receptors, CD-36, MSR-1, and LOX-1. Another critical finding is the ability of the degradable ferulate-based polymer nanoparticles to lower macrophage reactive oxygen species (ROS) levels, a precursor to apoptosis and plaque escalation. The degradable ferulic acid-based polymer nanoparticles hold significant promise as a means to alter the treatment and progression of atherosclerosis.
Assuntos
Anti-Inflamatórios , Aterosclerose , Ácidos Cumáricos , Células Espumosas/metabolismo , Lipogênese/efeitos dos fármacos , Nanopartículas , Polianidridos , Espécies Reativas de Oxigênio/metabolismo , Anti-Inflamatórios/farmacologia , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Aterosclerose/patologia , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Células Espumosas/patologia , Humanos , Nanopartículas/química , Nanopartículas/uso terapêutico , Polianidridos/química , Polianidridos/farmacologiaRESUMO
While the development of second- and third-generation drug-eluting stents (DES) have significantly improved patient outcomes by reducing smooth muscle cell (SMC) proliferation, DES have also been associated with an increased risk of late-stent thrombosis due to delayed re-endothelialization and hypersensitivity reactions from the drug-polymer coating. Furthermore, DES anti-proliferative agents do not counteract the upstream oxidative stress that triggers the SMC proliferation cascade. In this study, we investigate biocompatible amphiphilic macromolecules (AMs) that address high oxidative lipoprotein microenvironments by competitively binding oxidized lipid receptors and suppressing SMC proliferation with minimal cytotoxicity. To determine the influence of nanoscale assembly on proliferation, micelles and nanoparticles were fabricated from AM unimers containing a phosphonate or carboxylate end-group, a sugar-based hydrophobic domain, and a hydrophilic poly(ethylene glycol) domain. The results indicate that when SMCs are exposed to high levels of oxidized lipid stimuli, nanotherapeutics inhibit lipid uptake, downregulate scavenger receptor expression, and attenuate scavenger receptor gene transcription in SMCs, and thus significantly suppress proliferation. Although both functional end-groups were similarly efficacious, nanoparticles suppressed oxidized lipid uptake and scavenger receptor expression more effectively compared to micelles, indicating the relative importance of formulation characteristics (e.g., higher localized AM concentrations and nanotherapeutic stability) in scavenger receptor binding as compared to AM end-group functionality. Furthermore, AM coatings significantly prevented platelet adhesion to metal, demonstrating its potential as an anti-platelet therapy to treat thrombosis. Thus, AM micelles and NPs can effectively repress early stage SMC proliferation and thrombosis through non-cytotoxic mechanisms, highlighting the promise of nanomedicine for next-generation cardiovascular therapeutics.
Assuntos
Substâncias Macromoleculares/farmacologia , Miócitos de Músculo Liso/citologia , Nanopartículas/química , Adesividade Plaquetária , Tensoativos/farmacologia , Proliferação de Células , Regulação para Baixo , Endocitose , Humanos , Lipoproteínas LDL , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Receptores Depuradores/metabolismo , Tensoativos/síntese química , Tensoativos/química , Trombose/patologia , Transcrição GênicaRESUMO
AIMS: Atherosclerotic development is exacerbated by two coupled pathophysiological phenomena in plaque-resident cells: modified lipid trafficking and inflammation. To address this therapeutic challenge, we designed and investigated the efficacy in vitro and ex vivo of a novel 'composite' nanotherapeutic formulation with dual activity, wherein the nanoparticle core comprises the antioxidant α-tocopherol and the shell is based on sugar-derived amphiphilic polymers that exhibit scavenger receptor binding and counteract atherogenesis. METHODS AND RESULTS: Amphiphilic macromolecules were kinetically fabricated into serum-stable nanoparticles (NPs) using a core/shell configuration. The core of the NPs comprised either of a hydrophobe derived from mucic acid, M12, or the antioxidant α-tocopherol (α-T), while an amphiphile based on PEG-terminated M12 served as the shell. These composite NPs were then tested and validated for inhibition of oxidized lipid accumulation and inflammatory signalling in cultures of primary human macrophages, smooth muscle cells, and endothelial cells. Next, the NPs were evaluated for their athero-inflammatory effects in a novel ex vivo carotid plaque model and showed similar effects within human tissue. Incorporation of α-T into the hydrophobic core of the NPs caused a pronounced reduction in the inflammatory response, while maintaining high levels of anti-atherogenic efficacy. CONCLUSIONS: Sugar-based amphiphilic macromolecules can be complexed with α-T to establish new anti-athero-inflammatory nanotherapeutics. These dual efficacy NPs effectively inhibited key features of atherosclerosis (modified lipid uptake and the formation of foam cells) while demonstrating reduction in inflammatory markers based on a disease-mimetic model of human atherosclerotic plaques.
Assuntos
Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Placa Aterosclerótica/tratamento farmacológico , Células Espumosas/efeitos dos fármacos , Células Espumosas/metabolismo , Humanos , Inflamação/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Nanopartículas/uso terapêutico , Placa Aterosclerótica/metabolismoRESUMO
Pulmonary immunization poses the unique challenge of balancing vaccine efficacy with minimizing inflammation in the respiratory tract. While previous studies have shown that mice immunized intranasally with F1-V-loaded polyanhydride nanoparticles are protected from a lethal challenge with Yersinia pestis, little is known about the initial interaction between the nanoparticles and immune cells following intranasal administration. Here, the deposition within the lung and internalization by phagocytic cells of polyanhydride nanovaccines encapsulating F1-V are compared with that of soluble F1-V alone or F1-V adjuvanted with monophosphoryl lipid A (MPLA). Encapsulation of F1-V into polyanhydride nanoparticles prolonged its presence while F1-V administered with MPLA is undetectable within 48 h. The inflammation induced by the polyanhydride nanovaccine is mild compared with the marked inflammation induced by the MPLA-adjuvanted F1-V. Even though F1-V delivered with saline is detected in the lung 48 h after administration, it is known that this regimen does not elicit a protective immune response. The prolonged F1-V presence in the lung in concert with the mild inflammatory response provided by the nanovaccine provides new insights into the development of protective immune responses with a single intranasal dose.
Assuntos
Pulmão/citologia , Pulmão/metabolismo , Nanoestruturas/química , Vacinas/farmacocinética , Adjuvantes Imunológicos/química , Animais , Feminino , Imunização , Lipídeo A/análogos & derivados , Lipídeo A/química , Lipídeo A/imunologia , Pulmão/química , Camundongos , Camundongos Endogâmicos C57BL , Peste/prevenção & controle , Pneumonia , Polianidridos , Vacinas/química , Vacinas/imunologia , Yersinia pestis/imunologiaRESUMO
Several challenges are associated with current vaccine strategies, including repeated immunizations, poor patient compliance, and limited approved routes for delivery, which may hinder induction of protective immunity. Thus, there is a need for new vaccine adjuvants capable of multi-route administration and prolonged antigen release at the site of administration by providing a depot within tissue. In this work, we designed a combinatorial platform to investigate the in vivo distribution, depot effect, and localized persistence of polyanhydride nanoparticles as a function of nanoparticle chemistry and administration route. Our observations indicated that the route of administration differentially affected tissue residence times. All nanoparticles rapidly dispersed when delivered intranasally but provided a depot when administered parenterally. When amphiphilic and hydrophobic nanoparticles were administered intranasally, they persisted within lung tissue. These results provide insights into the chemistry- and route-dependent distribution and tissue-specific association of polyanhydride nanoparticle-based vaccine adjuvants.
Assuntos
Adjuvantes Imunológicos/farmacocinética , Preparações de Ação Retardada/farmacocinética , Nanopartículas/metabolismo , Polianidridos/farmacocinética , Vacinas , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Administração Intranasal , Análise de Variância , Animais , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos , Corantes Fluorescentes/química , Injeções Intramusculares , Pulmão/química , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Polianidridos/administração & dosagem , Polianidridos/química , Distribuição Tecidual , Imagem Corporal TotalRESUMO
Atherogenesis, the uncontrolled deposition of modified lipoproteins in inflamed arteries, serves as a focal trigger of cardiovascular disease (CVD). Polymeric biomaterials have been envisioned to counteract atherogenesis based on their ability to repress scavenger mediated uptake of oxidized lipoprotein (oxLDL) in macrophages. Following the conceptualization in our laboratories of a new library of amphiphilic macromolecules (AMs), assembled from sugar backbones, aliphatic chains and poly(ethylene glycol) tails, a more rational approach is necessary to parse the diverse features such as charge, hydrophobicity, sugar composition and stereochemistry. In this study, we advance a computational biomaterials design approach to screen and elucidate anti-atherogenic biomaterials with high efficacy. AMs were quantified in terms of not only 1D (molecular formula) and 2D (molecular connectivity) descriptors, but also new 3D (molecular geometry) descriptors of AMs modeled by coarse-grained molecular dynamics (MD) followed by all-atom MD simulations. Quantitative structure-activity relationship (QSAR) models for anti-atherogenic activity were then constructed by screening a total of 1164 descriptors against the corresponding, experimentally measured potency of AM inhibition of oxLDL uptake in human monocyte-derived macrophages. Five key descriptors were identified to provide a strong linear correlation between the predicted and observed anti-atherogenic activity values, and were then used to correctly forecast the efficacy of three newly designed AMs. Thus, a new ligand-based drug design framework was successfully adapted to computationally screen and design biomaterials with cardiovascular therapeutic properties.
Assuntos
Aterosclerose/tratamento farmacológico , Materiais Biocompatíveis/farmacologia , Simulação por Computador , Desenho de Fármacos , Aterosclerose/prevenção & controle , Materiais Biocompatíveis/química , Carboidratos/química , Biologia Computacional/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Ligantes , Lipoproteínas LDL/metabolismo , Substâncias Macromoleculares/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Estrutura Molecular , Polietilenoglicóis , Polímeros/química , Relação Quantitativa Estrutura-Atividade , Relação Estrutura-AtividadeRESUMO
Efficacy, purity, safety, and potency are important attributes of vaccines. Polyanhydride particles represent a novel class of vaccine adjuvants and delivery platforms that have demonstrated the ability to enhance the stability of protein antigens as well as elicit protective immunity against bacterial pathogens. This work aims to elucidate the biocompatibility, inflammatory reactions, and particle effects on mice injected with a 5 mg dose of polyanhydride nanoparticles via common parenteral routes (subcutaneous and intramuscular). Independent of polymer chemistry, nanoparticles more effectively disseminated away from the injection site as compared to microparticles, which exhibited a depot effect. Using fluorescent probes, the in vivo distribution of three formulations of nanoparticles, following subcutaneous administration, indicated migration away from the injection site. Less inflammation was observed at the injection sites of mice-administered nanoparticles as compared to Alum and incomplete Freund's adjuvant. Furthermore, histological evaluation revealed minimal adverse injection site reactions and minimal toxicological effects associated with the administration of nanoparticles at 30 days post-administration. Collectively, these results demonstrate that polyanhydride nanoparticles do not induce inflammation as a cumulative effect of particle persistence or degradation and are, therefore, a viable candidate for a vaccine delivery platform.
Assuntos
Materiais Biocompatíveis/efeitos adversos , Portadores de Fármacos/efeitos adversos , Nanopartículas/efeitos adversos , Polianidridos/efeitos adversos , Vacinas/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Animais , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Vacinas/efeitos adversosRESUMO
Pneumococcal surface protein A (PspA) is a choline-binding protein which is a virulence factor found on the surface of all Streptococcus pneumoniae strains. Vaccination with PspA has been shown to be protective against a lethal challenge with S. pneumoniae, making it a promising immunogen for use in vaccines. Herein the design of a PspA-based subunit vaccine using polyanhydride nanoparticles as a delivery platform is described. Nanoparticles based on sebacic acid (SA), 1,6-bis-(p-carboxyphenoxy)hexane (CPH) and 1,8-bis-(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG), specifically 50:50 CPTEG:CPH and 20:80 CPH:SA, were used to encapsulate and release PspA. The protein released from the nanoparticle formulations retained its primary and secondary structure as well as its antigenicity. The released PspA was also biologically functional based on its ability to bind to apolactoferrin and prevent its bactericidal activity against Escherichia coli. When the PspA nanoparticle formulations were administered subcutaneously to mice they elicited a high titer and high avidity anti-PspA antibody response. Together these studies provide a framework for the rational design of a vaccine against S. pneumoniae based on polyanhydride nanoparticles.
Assuntos
Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/imunologia , Ácidos Decanoicos/química , Preparações de Ação Retardada/síntese química , Nanocápsulas/química , Polianidridos/química , Poliésteres/química , Streptococcus pneumoniae/imunologia , Animais , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/química , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/química , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/síntese química , Vacinas Bacterianas/imunologia , Preparações de Ação Retardada/administração & dosagem , Difusão , Teste de Materiais , Camundongos , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Tamanho da Partícula , Conformação Proteica , Streptococcus pneumoniae/efeitos dos fármacosRESUMO
Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with conventional one-sample-at-a-time synthesis techniques, a more recent high-throughput approach has been developed enabling the synthesis and testing of large libraries of polyanhydrides(1). This will facilitate more efficient optimization and design process of these biomaterials for drug and vaccine delivery applications. The method in this work describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries. In this robotically operated method (Figure 1), linear actuators and syringe pumps are controlled by LabVIEW, which enables a hands-free automated protocol, eliminating user error. Furthermore, this method enables the rapid fabrication of micro-scale polymer libraries, reducing the batch size while resulting in the creation of multivariant polymer systems. This combinatorial approach to polymer synthesis facilitates the synthesis of up to 15 different polymers in an equivalent amount of time it would take to synthesize one polymer conventionally. In addition, the combinatorial polymer library can be fabricated into blank or protein-loaded geometries including films or nanoparticles upon dissolution of the polymer library in a solvent and precipitation into a non-solvent (for nanoparticles) or by vacuum drying (for films). Upon loading a fluorochrome-conjugated protein into the polymer libraries, protein release kinetics can be assessed at high-throughput using a fluorescence-based detection method (Figures 2 and 3) as described previously(1). This combinatorial platform has been validated with conventional methods(2) and the polyanhydride film and nanoparticle libraries have been characterized with (1)H NMR and FTIR. The libraries have been screened for protein release kinetics, stability and antigenicity; in vitro cellular toxicity, cytokine production, surface marker expression, adhesion, proliferation and differentiation; and in vivo biodistribution and mucoadhesion(1-11). The combinatorial method developed herein enables high-throughput polymer synthesis and fabrication of protein-loaded nanoparticle and film libraries, which can, in turn, be screened in vitro and in vivo for optimization of biomaterial performance.
Assuntos
Materiais Biocompatíveis/química , Ensaios de Triagem em Larga Escala/métodos , Nanopartículas/química , Polímeros/química , Proteínas/química , Materiais Biocompatíveis/síntese química , Ensaios de Triagem em Larga Escala/instrumentação , Membranas Artificiais , Polianidridos/síntese química , Polianidridos/química , Polímeros/síntese químicaRESUMO
Several challenges currently exist for rational design of functional tissue engineering constructs within the host, which include appropriate cellular integration, avoidance of bacterial infections, and low inflammatory stimulation. This work describes a novel class of biodegradable, amphiphilic polyanhydrides with many desirable protein-material and cell-material attributes capable of confronting these challenges. The biocompatible amphiphilic polymer films were shown to release laminin in a stable and controlled manner, promote neural cell adhesion and differentiation, and evade inflammatory responses of the immune system. Using high-throughput approaches, it was shown that polymer chemistry plays an integral role in controlling cell-film interactions, which suggests that these polyanhydrides can be tailored to achieve the desired cell adhesion and differentiation while minimizing immune recognition. These findings have important implications for development of engineered constructs to regulate differentiation and target the growth of transplanted cells in stem cell-based therapies to treat nervous system disorders.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Neurais/citologia , Polianidridos/farmacologia , Tensoativos/farmacologia , Animais , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Hexanos/química , Hexanos/farmacologia , Humanos , Imunidade/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Polianidridos/química , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Tensoativos/químicaRESUMO
Polyanhydrides are a class of degradable biomaterials that have shown much promise for applications in drug and vaccine delivery. Their properties can be tailored for controlled drug release, drug/protein stability, and immune regulation (adjuvant effect). Identifying the relationship between the molecular structures of the polymers and the drug release kinetics profiles would help understand the release mechanism and aid in the accurate prediction of drug release and the rational design of polymer-based drug carrier systems. The molecular structure descriptors that had the most impact on the release kinetics were identified using a prediction/optimization data mining approach. Using this new approach for modeling nonlinear release kinetics behavior, we determined that the descriptors which had the greatest effect on the release kinetics were the number of backbone -COO- nonconjugated bonds, the number of aromatic rings, and the number of -CH2- bonds.
Assuntos
Materiais Biocompatíveis , Técnicas de Química Combinatória , Proteínas/química , Espectroscopia de Ressonância MagnéticaRESUMO
This work demonstrates that amphiphilic polyanhydride microparticles based on co-polymers of 1,6-bis(p-carboxyphenoxy)hexane (CPH) and 1,6-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG) provide stabilizing environments for proteins. A cryogenic atomization method was used to fabricate protein-loaded polyanhydride microparticles. These microparticles were tested for their ability to provide controlled delivery of lipocalin 2 (Lcn2) and to maintain its structure and function. Lcn2 is an acute-phase protein suspected to play a role in cell migration and tissue repair. The in vitro release kinetics of Lcn2 from the microparticles were a function of the chemistry of the polymer carrier. The biological activity of Lcn2 released from polyanhydride microparticles was investigated by its ability to stimulate migration of human colon epithelial cells (HCT116). Lcn2 released from 50:50 and 20:80 CPTEG/CPH microparticles maintained its biological activity as demonstrated by the increased rate of cell migration. In addition, the Lcn2-loaded 50:50 and 20:80 CPTEG/CPH microparticles promoted cell migration over that of the Lcn2 administered alone. This was interpreted as the ability of the amphiphilic microparticles to stabilize the encapsulated protein and release it in a controlled manner over a period of time. This work demonstrates the potential for therapeutic use of amphiphilic polyanhydride microparticles as protein/drug carriers.