RESUMEN
Avascular transplantation of frozen-thawed testicular tissue fragments represents a potential future technique for fertility restoration in boys with cancer. A significant loss of spermatogonia was observed in xeno-transplants of human tissue most likely due to the hypoxic period before revascularization. To reduce the effect of hypoxia-reoxygenation injuries, several options have already been explored, like encapsulation in alginate hydrogel and supplementation with nanoparticles delivering a necrosis inhibitor (NECINH) or VEGF. While these approaches improved short-term (5 days) vascular surfaces in grafts, neovessels were not maintained up to 21 days; i.e., the time needed for achieving vessel stabilization. To better support tissue grafts, nanoparticles loaded with VEGF, PDGF and NECINH were developed. Testicular tissue fragments from 4-5-week-old mice were encapsulated in calcium-alginate hydrogels, either non-supplemented (control) or supplemented with drug-loaded nanoparticles (VEGF-nanoparticles; VEGF-nanoparticles + PDGF-nanoparticles; NECINH-nanoparticles; VEGF-nanoparticles + NECINH-nanoparticles; and VEGF-nanoparticles + PDGF-nanoparticles + NECINH-nanoparticles) before auto-transplantation. Grafts were recovered after 5 or 21 days for analyses of tissue integrity (hematoxylin-eosin staining), spermatogonial survival (immuno-histo-chemistry for promyelocytic leukemia zinc finger) and vascularization (immuno-histo-chemistry for α-smooth muscle actin and CD-31). Our results showed that a combination of VEGF and PDGF nanoparticles increased vascular maturity and induced a faster maturation of vascular structures in grafts.
Asunto(s)
Hidrogeles/química , Nanopartículas/administración & dosificación , Neovascularización Fisiológica/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/administración & dosificación , Testículo/trasplante , Factor A de Crecimiento Endotelial Vascular/administración & dosificación , Alginatos/química , Animales , Liberación de Fármacos , Preservación de la Fertilidad/métodos , Humanos , Masculino , Ratones Endogámicos , Nanopartículas/química , Factor de Crecimiento Derivado de Plaquetas/química , Factor de Crecimiento Derivado de Plaquetas/farmacocinética , Espermatogonias/efectos de los fármacos , Testículo/irrigación sanguínea , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinéticaRESUMEN
In this study we produced a set of in vitro culture platforms to model vascular cell responses to growth factors and factor delivery vehicles. Two of the systems (whole vessel and whole lung vascular development) were supported by microfluidic systems facilitating media circulation and waste removal. We assessed vascular endothelial growth factor (VEGF) delivery by Pluronic F-127 hydrogel, 30â¯nm pore-sized microparticles (MPs), 60â¯nm pore-sized MP or a 50/50 mixture of 30 and 60â¯nm pore-sized MP. VEGF was delivered to porcine acellular lung vascular scaffolds (2.5â¯cm2 square pieces or whole 3D segments of acellular blood vessels) as well as whole acellular lung scaffolds. Scaffold-cell attachment was examined as was vascular tissue formation. We showed that a 50/50 mixture of 30 and 60â¯nm pore-sized silicon wafer MPs allowed for long-term release of VEGF within the scaffold vasculature and supported vascular endothelial tissue development during in vitro culture.
Asunto(s)
Portadores de Fármacos , Células Endoteliales/metabolismo , Hidrogeles , Pulmón , Neovascularización Fisiológica/efectos de los fármacos , Andamios del Tejido/química , Factor A de Crecimiento Endotelial Vascular , Animales , Técnicas de Cultivo de Célula , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Preparaciones de Acción Retardada/farmacología , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacología , Hidrogeles/química , Hidrogeles/farmacocinética , Hidrogeles/farmacología , Pulmón/irrigación sanguínea , Pulmón/química , Porosidad , Porcinos , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
BACKGROUND: Current common techniques for repairing calvarial defects by autologous bone grafting and alloplastic implants have significant limitations. In this study, the authors investigated a novel alternative approach to bone repair based on peptide amphiphile nanofiber gels that are engineered to control the release of vascular endothelial growth factor (VEGF) to recruit circulating stem cells to a site of bone regeneration and facilitate bone healing by bone morphogenetic protein-2 (BMP-2). METHODS: VEGF release kinetics from peptide amphiphile gels were evaluated. Chemotactic functional scaffolds were fabricated by combining collagen sponges with peptide amphiphile gels containing VEGF. The in vitro and in vivo chemotactic activities of the scaffolds were evaluated by measuring mesenchymal stem cell migration, and angiogenic capability of the scaffolds was also evaluated. Large-scale rodent cranial bone defects were created to evaluate bone regeneration after implanting the scaffolds and other control materials. RESULTS: VEGF was released from peptide amphiphile in a controlled-release manner. In vitro migration of mesenchymal stem cells was significantly greater when exposed to chemotactic functional scaffolds compared to control scaffolds. In vivo chemotaxis was evidenced by migration of tracer-labeled mesenchymal stem cells to the chemotactic functional scaffolds. Chemotactic functional scaffolds showed significantly increased angiogenesis in vivo. Successful bone regeneration was noted in the defects treated with chemotactic functional scaffolds and BMP-2. CONCLUSIONS: The authors' observations suggest that this bioengineered construct successfully acts as a chemoattractant for circulating mesenchymal stem cells because of controlled release of VEGF from the peptide amphiphile gels. The chemotactic functional scaffolds may play a role in the future design of clinically relevant bone graft substitutes for large-scale bone defects.
Asunto(s)
Osteogénesis/efectos de los fármacos , Proteínas Recombinantes/administración & dosificación , Regeneración/efectos de los fármacos , Cráneo/cirugía , Andamios del Tejido/química , Factor A de Crecimiento Endotelial Vascular/administración & dosificación , Animales , Proteína Morfogenética Ósea 2/administración & dosificación , Proteína Morfogenética Ósea 2/farmacocinética , Quimiotaxis/efectos de los fármacos , Colágeno/administración & dosificación , Colágeno/farmacocinética , Modelos Animales de Enfermedad , Femenino , Geles , Humanos , Células Madre Mesenquimatosas/fisiología , Ratones , Nanofibras/administración & dosificación , Neovascularización Fisiológica/efectos de los fármacos , Péptidos/administración & dosificación , Péptidos/farmacocinética , Proteínas Recombinantes/farmacocinética , Cráneo/lesiones , Cráneo/fisiología , Ingeniería de Tejidos/métodos , Factor A de Crecimiento Endotelial Vascular/farmacocinéticaRESUMEN
To enhance the angiogenic capacity of tissue-engineered peripheral nerves, we have constructed revascularized tissue-engineered nerves based on a vascular endothelial growth factor (VEGF)-heparin sustained release system. However, the effects of the repair of large peripheral nerve defects are not known. In this study, we used the above revascularized tissue-engineered nerve to repair large nerve defects in rats. The repair effects were observed through general observation, functional evaluation of nerve regeneration, ultrasound examination, neural electrophysiology, wet weight ratio of bilateral gastrocnemius muscle, histological evaluation, and quantitative real-time polymerase chain reaction (PCR) analysis. The results showed that the tissue-engineered peripheral nerve based on a VEGF-heparin sustained release system can achieve early vascularization and restore blood supply in the nerve graft area. The realization of early vascularization in the area of the nerve defect greatly promotes the speed of nerve regeneration and reconstruction in the area of the nerve defect, which greatly advances the process of nerve repair and reconstruction and accelerates the restoration of the normal morphological structure and function of peripheral nerves.
Asunto(s)
Heparina , Regeneración Nerviosa/efectos de los fármacos , Traumatismos de los Nervios Periféricos , Ingeniería de Tejidos , Factor A de Crecimiento Endotelial Vascular , Animales , Preparaciones de Acción Retardada/farmacocinética , Preparaciones de Acción Retardada/farmacología , Heparina/farmacocinética , Heparina/farmacología , Masculino , Traumatismos de los Nervios Periféricos/metabolismo , Traumatismos de los Nervios Periféricos/patología , Traumatismos de los Nervios Periféricos/terapia , Ratas , Ratas Sprague-Dawley , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
Administration of RC28-E, a VEGF/bFGF dual decoy receptor (IgG1 Fc-fusion protein), have shown relative therapeutic value in ocular in vivo models, including laser-induced choroidal neovascularization (CNV) in monkeys and streptozotocin (STZ)-induced diabetic retinopathy (DR) in rats. In the present study, we have elucidated the pharmacokinetics profiles of RC28-E at the systemic, vitreous and aqueous humor after administration in a primate model (Macaca fascicularis). Moreover, here we tease out the ocular tissue distribution of RC28-E after intravitreal administration, and we also determine the systemic bioavailability after both intravitreal and intravenous administration. Our results show that RC28-E is rapidly and well-distributed into ocular tissues after intravitreal administration. Drug exposure in choroid and retina was approximately one-quarter and one-twelfth of that in vitreous humor, while its half-life in vitreous and aqueous humor were well-sustained (3.3 and 3.0 days). Remarkably, RC28-E could cross the blood-ocular barrier, and the systemic bioavailability of RC28-E was ~25%. No drug accumulation after multiple administration was noticed, but low titers of antibody produce against RC28-E were detected. Overall, RC28-E exhibited high clinical value due to adequate pharmacokinetic profiling, safety and efficacy.
Asunto(s)
Humor Acuoso/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacocinética , Proteínas Recombinantes de Fusión/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Cuerpo Vítreo/metabolismo , Animales , Disponibilidad Biológica , Barrera Hematorretinal , Coroides/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Factor 2 de Crecimiento de Fibroblastos/inmunología , Fragmentos Fc de Inmunoglobulinas/inmunología , Inmunoglobulina G/inmunología , Inyecciones Intravítreas , Cristalino/metabolismo , Macaca fascicularis , Masculino , Proteínas Recombinantes de Fusión/inmunología , Retina/metabolismo , Distribución Tisular , Factor A de Crecimiento Endotelial Vascular/inmunologíaRESUMEN
The accurate delivery of precise amounts of drugs to a specific location can considerably affect various clinical applications. The precise control of drug amount and position is crucial to a successful drug delivery. This paper proposes the use of poly(lactide-co-glycolicacid) (PLGA)-based microspheres to contain precise amounts of drugs and an optical tweezer manipulator to transport these drug-containing microspheres to their targeted sites in vivo. The drugs were delivered by the PLGA-based microspheres to the yolk sac of zebrafish embryos, and a sustained drug release was observed to examine the anti-angiogenesis and angiogenesis activities. The PLGA-based microspheres degraded in zebrafish, thereby verifying that these microspheres can be used as drug carriers in vivo to ensure good biocompatibility and biodegradation. The proposed precise drug delivery approach can be used in protein tests and drug property characterization in vivo.
Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Microesferas , Pinzas Ópticas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Inductores de la Angiogénesis/farmacocinética , Inductores de la Angiogénesis/farmacología , Animales , Preparaciones de Acción Retardada , Embrión no Mamífero/metabolismo , Microscopía Fluorescente , Neovascularización Fisiológica/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacología , Pez CebraRESUMEN
Triple negative breast cancer (TNBC) is the most difficult breast cancer subtype to treat. TNBC patients have significantly higher expression of vascular endothelial growth factor (VEGF) in tumors compared to non-TNBC patients. VEGF not only exerts its pro-angiogenic effects on endothelial cells but also acts as a survival and autocrine growth factor for VEGF receptor (VEGFR) expressing cancer cells. Silencing the expression of VEGF is therefore a potential therapy for TNBC. Methods: A novel biocompatible linear copolymer poly[bis(ε-Lys-PEI)Glut-PEG] (PLEGP) was developed to deliver VEGF siRNA for TNBC therapy. The copolymer is composed of lysine and glutaric acid, a natural metabolite of amino acids in the body. Low-molecular weight polyethyleneimine (PEI) was grafted to the copolymer to efficiently condense siRNA into nanocomplex without inducing cytotoxicity. Various in vitro studies were performed to evaluate the stability, cellular uptake, tumor penetration, and biological activities of the VEGF siRNA nanocomplex. The anti-tumor activities of the nanocomplex was also evaluated in an orthotopic TNBC mouse model. Results: PEIs with different molecular weights were evaluated, and the copolymer PLEGP1800 was able to easily form a stable nanocomplex with siRNAs and protect them from serum degradation. The siRNA/PLEGP1800 nanocomplex exhibited negligible cytotoxicity but showed high cellular uptake, high transfection efficiency, and high tumor penetration. In vitro activity studies showed that the siRNA nanocomplex significantly inhibited migration and invasion of TNBC cells. Moreover, the VEGF siRNA nanocomplex efficiently inhibited tumor growth in an orthotopic TNBC mouse model and down-regulated VEGF expression in the tumor. Conclusion: PLEGP1800 is a safe and efficient copolymer to deliver siRNAs for TNBC therapy. It could potentially be applied to other cancers by changing the cargo and incorporating tumor-specific ligands.
Asunto(s)
Materiales Biocompatibles/química , Nanopartículas/química , ARN Interferente Pequeño/administración & dosificación , Neoplasias de la Mama Triple Negativas/terapia , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Muerte Celular , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Endocitosis , Femenino , Silenciador del Gen , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Luciferasas/metabolismo , Ratones Desnudos , Invasividad Neoplásica , Neovascularización Fisiológica , Polietilenglicoles/química , Polietileneimina/química , Esferoides Celulares/citología , Distribución Tisular , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
Medical coatings cooperated with biomacromolecules can regulate biological events and tissue responses, thus increasing medical implant longevity and providing improved and/or new therapeutic functions. In particular, medical coatings, which can load the correct species and doses of biomacromolecules according to individual diagnoses, will significantly optimize treatment effects and satisfy the rising clinical need of "precision medicine". Herein, we report on a dynamic microporous coating with an ultrafast self-healing property to fulfill the "load-and-play" concept for "precision medicine". A structure-switchable coating based on poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) triblock copolymer network is constructed. The coating can be switched to microporous morphology via a water swelling and freeze-drying process. Then, through a mild thermo-trigger as low as 40⯰C, this spongy coating can undergo self-healing to switch back to a pore-free structure within minutes to even 5â¯s. Based on this dynamic coating, we suggest a simple and versatile method to encapsulate biomacromolecules for surface-mediated delivery. The ultrafast self-healing of the microporous structure enables uniform incorporation of biomacromolecules with an easily achieved high loading of albumin of 16.3⯵g/cm2 within 1â¯min. More importantly, controllable encapsulation can be realized by simple control of the concentration of the loading solution. We further demonstrate that the encapsulated biomacromolecules retained their bioactivity. This work may benefit clinicians with flexibility to provide personalized medical coatings for individual patients during treatment.
Asunto(s)
Preparaciones de Acción Retardada/química , Poliésteres/química , Polietilenglicoles/química , Animales , Stents Liberadores de Fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Porosidad , Conejos , Albúmina Sérica Bovina/administración & dosificación , Albúmina Sérica Bovina/farmacocinética , Temperatura , Factor A de Crecimiento Endotelial Vascular/administración & dosificación , Factor A de Crecimiento Endotelial Vascular/farmacocinéticaRESUMEN
We aim to test the application of heparin, bFGF, and VEGF 145 grafted acellular vascular scaffold in small diameter vascular graft. The amount of bFGF and VEGF 145 were determined by ELISA. Femoral artery transplantation was performed. Mechanical strength of acellular vascular scaffolds was determined. Angiography was performed for blood vessel patency. Factor VIII and α2-actin expression was detected by immunohistochemistry. bFGF and VEGF 145 had stable release at 60 and 70 days in vitro, and the release rate of VEGF 145 was slightly slower than that of bFGF. After transplantation, 9 months of the vascular patency rate was 100% at 1, 3, and 9 months, and, was up to 90% at 18 months, while the patency rate in group with grafted heparin only at 1-month was 60%, at 3-month was 40%, at 9-month was 15%, and at 18-month was 10%. The blood vessels taken after 18 months had no significant difference in the mechanical properties between the transplanted and the natural vessels. Positive expression of factor VIII and α2-actin was observed. The heparinized and bFGF and VEGF 145 grafted allogeneic vascular acellular scaffolds are preliminarily obtained, which show good biocompatibility and patency and are of great importance for small diameter vascular graft. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 00B: 000-000, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 672-679, 2019.
Asunto(s)
Bioprótesis , Prótesis Vascular , Arteria Femoral , Factor 2 de Crecimiento de Fibroblastos , Heparina , Ensayo de Materiales , Andamios del Tejido/química , Factor A de Crecimiento Endotelial Vascular , Animales , Implantación de Prótesis Vascular , Perros , Arteria Femoral/metabolismo , Arteria Femoral/patología , Arteria Femoral/cirugía , Factor 2 de Crecimiento de Fibroblastos/química , Factor 2 de Crecimiento de Fibroblastos/farmacocinética , Factor 2 de Crecimiento de Fibroblastos/farmacología , Heparina/química , Heparina/farmacocinética , Heparina/farmacología , Humanos , Conejos , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
Large scale cortical allografts suffer from poor incorporation and healing and often end in graft failure 5-10 years after implantation. To reduce these failures we have developed a growth-factor loaded cortical allograft capable of delivering one or two factors with a degree of temporal control and precision that permits the early release of one growth factor followed by the later and more sustained release of the other. We have loaded vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2), both critical components of bone formation and repair, onto cortical long bone allografts such that the VEGF is released first and followed shortly by BMP-2. Coated and factor-loaded allografts were placed into a critical sized rat femoral segmental defect and allowed to heal for either 4 or 8 weeks. Healing at each time point was compared to allografts loaded with only BMP-2 and allografts containing no growth factors. Results indicate statistically significant increases in new bone formation from 4 to 8 weeks around allografts loaded with both VEGF and BMP-2 over allografts with no growth factor, suggesting that factor-loaded polymer-coated allografts delivering multiple factors with temporal precision may provide a new off-the-shelf tool to the orthopedic surgeon for management of large-scale orthopedic bone defects. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1002-1010, 2019.
Asunto(s)
Proteína Morfogenética Ósea 2 , Trasplante Óseo , Fémur , Osteogénesis , Factor A de Crecimiento Endotelial Vascular , Aloinjertos , Animales , Proteína Morfogenética Ósea 2/química , Proteína Morfogenética Ósea 2/farmacocinética , Proteína Morfogenética Ósea 2/farmacología , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Preparaciones de Acción Retardada/farmacología , Fémur/lesiones , Fémur/metabolismo , Fémur/cirugía , Masculino , Ratas , Ratas Sprague-Dawley , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
The use of nanomaterials as carriers for the delivery of growth factors has been applied to a multitude of applications in tissue engineering. However, issues of toxicity, stability, and systemic effects of these platforms have yet to be fully understood, especially for cardiovascular applications. Here, we proposed a delivery system composed of poly(dl-lactide- co-glycolide) acid (PLGA) and porous silica nanoparticles (pSi) to deliver vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF). The tight spatiotemporal release of these two proteins has been proven to promote neovascularization. In order to minimize tissue toxicity, localize the release, and maintain a stable platform, we conjugated two formulations of PLGA-pSi to electrospun (ES) gelatin to create a combined ES patch releasing both PDGF and VEGF. When compared to freely dispersed particles, the ES patch cultured in vitro with neonatal cardiac cells had significantly less particle internalization (2.0 ± 1.3%) compared to free PLGA-pSi (21.5 ± 6.1) or pSi (28.7 ± 2.5) groups. Internalization was positively correlated to late-stage apoptosis with PLGA-pSi and pSi groups having increased apoptosis compared to the untreated group. When implanted subcutaneously, the ES patch was shown to have greater neovascularization than controls evidenced by increased expression of α-SMA and CD31 after 21 days. Quantitative reverse transcription-polymerase chain reaction results support increased angiogenesis by the upregulation of VEGFA, VEGFR2, vWF, and COL3A1, exhibiting a synergistic effect with the release of VEGF-A164 and PDGF-BB after 21 days in vivo. The results of this study proved that the ES patch reduced cellular toxicity and may be tailored to have a dual release of growth factors promoting localized neovascularization.
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Becaplermina , Proliferación Celular/efectos de los fármacos , Miocitos Cardíacos , Nanopartículas/química , Neovascularización Fisiológica/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular , Animales , Becaplermina/química , Becaplermina/farmacocinética , Becaplermina/farmacología , Implantes de Medicamentos/química , Implantes de Medicamentos/farmacocinética , Implantes de Medicamentos/farmacología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Miocitos Cardíacos/trasplante , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacocinética , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Porosidad , Ratas , Dióxido de Silicio/química , Dióxido de Silicio/farmacocinética , Dióxido de Silicio/farmacología , Ingeniería de Tejidos , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
This study explored a new rosuvastatin calcium- and heparin-loaded poly(l-lactide- co-caprolactone) (PLCL) scaffold for covered stents for treating aneurysms. The mechanism of rosuvastatin-induced endothelialization via vascular endothelial growth factor (VEGF)-A elevation was further explored. Rosu50, Rosu75, Rosu100, and phosphate-buffered saline (PBS) nanofibrous scaffolds were fabricated by coaxial electrospinning and observed by electron microscopy. Anticoagulation and pro-endothelialization properties were tested. Sixteen rabbits were selected for an in vivo assay and underwent microsurgery to establish a carotid aneurysm model. The animals were treated with covered stents and followed for 4 months using digital subtraction angiography (DSA), electron microscopy, and histology. Rosuvastatin-treated human umbilical vein endothelial cell (HUVEC) viability, function, and VEGF-A modulation were further studied to elucidate the pro-endothelialization mechanism of rosuvastatin. Our study demonstrates that rosuvastatin and heparin can be incorporated into PLCL nanofibers via electrospinning. Rosu100 nanofiber scaffolds exhibited significant anticoagulation properties. The viability of HUVECs transferred to Rosu100 nanofiber scaffolds was increased significantly. In vivo, DSA revealed that the Rosu100 group had better outcomes than the PBS group. In addition, the Rosu100 stents induced more integrated endothelialization. Further study demonstrated that rosuvastatin promoted HUVEC viability and function in vitro. The effects of rosuvastatin may be attributed to an elevation in VEGF-A. We demonstrated that rosuvastatin- and heparin-loaded PLCL-covered stents show favorable anticoagulation and pro-endothelialization properties in vitro and in vivo in a rabbit aneurysm model. VEGF-A elevation played a crucial role in rosuvastatin-promoted endothelialization. This work provides an additional option for treating cerebral aneurysms with covered stents.
Asunto(s)
Aneurisma , Arterias Carótidas , Nanofibras/química , Rosuvastatina Cálcica , Stents , Factor A de Crecimiento Endotelial Vascular , Aneurisma/metabolismo , Aneurisma/patología , Aneurisma/cirugía , Animales , Caproatos/química , Caproatos/farmacocinética , Caproatos/farmacología , Arterias Carótidas/metabolismo , Arterias Carótidas/patología , Arterias Carótidas/cirugía , Heparina/química , Heparina/farmacocinética , Heparina/farmacología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Lactonas/química , Lactonas/farmacocinética , Lactonas/farmacología , Poliésteres/química , Poliésteres/farmacocinética , Poliésteres/farmacología , Conejos , Rosuvastatina Cálcica/química , Rosuvastatina Cálcica/farmacocinética , Rosuvastatina Cálcica/farmacología , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
Despite medical and surgical advancements for the treatment of cardiovascular disease, mortality and morbidity remain high. Therapeutic angiogenesis has been one approach to address the major clinical need for a more effective treatment to restoring blood flow in ischemic organs and tissues, but current progress in angiogenic drug delivery is inadequate at providing sufficient bioavailability without causing safety concerns. An injectable sulfonated reversible thermal gel composed of a polyurea conjugated with poly(N-isopropylacrylamide) and sulfonate groups has been developed for the delivery of angiogenic factors. The thermal gel allowed for the spatiotemporal control of vascular endothelial growth factor release with a decreased initial burst release and reduced release rate in vitro. A subcutaneous injection mouse model was used to evaluate efficacious vascularization and assess the inflammatory response due to a foreign body. Thermal gel injections showed substantial vascularization properties by inducing vessel formation, recruitment and differentiation of vascular endothelial cells, and vessel stabilization by perivascular cells, while infiltrating macrophages due to the thermal gel injections decreased over time. These results demonstrated effective localization and delivery of angiogenic factors for therapeutic angiogenesis. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3053-3064, 2018.
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Acrilamidas/química , Inductores de la Angiogénesis/administración & dosificación , Preparaciones de Acción Retardada/química , Geles/química , Polímeros/química , Sulfonas/química , Factor A de Crecimiento Endotelial Vascular/administración & dosificación , Inductores de la Angiogénesis/farmacocinética , Animales , Inyecciones Subcutáneas , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/farmacocinéticaRESUMEN
Tissue engineering bones take great advantages in massive bone defect repairing; under the induction of growth factors, seed cells differentiate into osteoblasts, and the scaffold materials gradually degrade and are replaced with neogenetic bones, which simulates the actual pathophysiological process of bone regeneration. However, mechanism research is required and further developed to instruct elements selection and optimization. In the present study, we prepared vascular endothelial growth factor/bone morphogenetic protein-2- nanohydroxyapatite/collagen (VEGF/ BMP-2- nHAC/ PLGAs) scaffolds and inoculated mouse MC3T3-E1 preosteoblasts to detect osteogenic indexes and activation of related signaling pathways. The hypothesis is to create a three-dimensional environment that simulates bone defect repairing, and p38 mitogen-activated kinase (p38) inhibitor was applied and osterix shRNA was transferred into mouse MC3T3-E1 preosteoblasts to further investigate the molecular mechanism of crosstalk between BMP-2 and VEGF. Our results demonstrated the following: (1) BMP-2 and VEGF were sustainably released from PLGAs microspheres. (2) nHAC/PLGAs scaffold occupied a three-dimensional porous structure and has excellent physical properties. (3) MC3T3-E1 cells proliferated and differentiated well in the scaffold. (4) Osteogenic differentiation related factors expression of VEGF/BMP-2 loaded scaffold was obviously higher than that of other groups; p38 inhibitor SB203580 decreased the nucleus/cytoplasm ratio of osterix expression. To conclude, the active artificial bone we prepared could provide a favorable growth space for MC3T3-E1 cells, and osteogenesis and maturation reinforced by simultaneous VEGF and BMP-2 treatment may be mainly through the activation of the p38 MAPK pathway to promote nuclear translocation of osterix protein.
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Proteína Morfogenética Ósea 2 , Osteoblastos/metabolismo , Osteogénesis/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Andamios del Tejido/química , Factor A de Crecimiento Endotelial Vascular , Animales , Proteína Morfogenética Ósea 2/química , Proteína Morfogenética Ósea 2/farmacocinética , Proteína Morfogenética Ósea 2/farmacología , Línea Celular , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Preparaciones de Acción Retardada/farmacología , Ratones , Ratas , Ingeniería de Tejidos/métodos , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
A promising strategy to accelerate bone generation is to deliver a combination of certain growth factors to the integration site via a controlled spatial and temporal delivery mode. Here, a composite hydrogel incorporating poly(lactide-co-glycolide) (PLGA) microspheres was accordingly prepared to load and deliver the osteogenic rhBMP-2 and angiogenic rhVEGF165 in the required manner. In addition, 2-N,6-O-sulphated chitosan (26SCS), which is a synergetic factor of growth factors, was incorporated in the composite hydrogel as well. The system showed a similar release behaviour of the two growth factors regardless of 26SCS inclusion. RhBMP-2 loaded in PLGA microspheres showed a sustained release over a period of 2 weeks, whereas rhVEGF165 loaded in hydrogel eluted almost completely from the hydrogel over the first 16 days. Both growth factors retained their efficacy, as quantified with relevant in vitro assays. Moreover, an enhanced cell response was achieved upon the delivery of dual growth factors, compared to that obtained with a single factor. Furthermore, in the presence of 26SCS, the system revealed significantly upregulated alkaline phosphatase activity, human umbilical vein endothelial cell proliferation, sprouting, nitric oxide secretion, and angiogenic gene expression. This study highlighted that the composite hydrogel incorporated with 26SCS appears to constitute a promising approach to deliver multiple growth factors. From our findings, we could also conclude that rhBMP-2 can promote angiogenesis and that the mechanism is worthy of further study in subsequent research.
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Proteína Morfogenética Ósea 2 , Regeneración Ósea/efectos de los fármacos , Quitosano , Hidrogeles , Microesferas , Factor A de Crecimiento Endotelial Vascular , Animales , Proteína Morfogenética Ósea 2/química , Proteína Morfogenética Ósea 2/farmacocinética , Proteína Morfogenética Ósea 2/farmacología , Línea Celular , Quitosano/análogos & derivados , Quitosano/química , Quitosano/farmacocinética , Quitosano/farmacología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Hidrogeles/química , Hidrogeles/farmacocinética , Hidrogeles/farmacología , Ratones , Ratas , Ratas Sprague-Dawley , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
BACKGROUND: Vascular endothelial growth factor has been found to accelerate compensatory lung growth after left pneumonectomy in mice. The aim of this study was to determine the natural history and the effects of vascular endothelial growth factor on compensatory lung growth in a large animal model. METHODS: To determine the natural history of compensatory lung growth, female Yorkshire piglets underwent a left pneumonectomy on days of life 10-11. Tissue harvest and volume measurement of the right lung were performed at baseline (nâ¯=â¯5) and on postoperative days 7 (nâ¯=â¯5), 14 (nâ¯=â¯4), and 21 (nâ¯=â¯5). For pharmacokinetic studies, vascular endothelial growth factor was infused via a central venous catheter, with plasma vascular endothelial growth factor levels measured at various time points. To test the effect of vascular endothelial growth factor on compensatory lung growth, 26 female Yorkshire piglets underwent a left pneumonectomy followed by daily infusion of vascular endothelial growth factor at 200 µg/kg or isovolumetric 0.9% NaCl (saline control). Lungs were harvested on postoperative day 7 for volume measurement and morphometric analyses. RESULTS: Compared with baseline, right lung volume after left pneumonectomy increased by factors of 2.1 ± 0.6, 3.3 ± 0.6, and 3.6 ± 0.4 on postoperative days 7, 14, and 21, respectively. The half-life of VEGF ranged from 89 to 144 minutes. Lesser doses of vascular endothelial growth factor resulted in better tolerance, volume of distribution, and clearance. Compared with the control group, piglets treated with vascular endothelial growth factor had greater lung volume (P < 0.0001), alveolar volume (Pâ¯=â¯0.001), septal surface area (Pâ¯=â¯0.007) and total alveolar count (Pâ¯=â¯0.01). CONCLUSION: Vascular endothelial growth factor enhanced alveolar growth in neonatal piglets after unilateral pneumonectomy.
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Pulmón/crecimiento & desarrollo , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Animales , Animales Recién Nacidos , Biometría , Evaluación Preclínica de Medicamentos , Femenino , Pulmón/efectos de los fármacos , Neumonectomía , Proteínas Recombinantes , Porcinos , Factor A de Crecimiento Endotelial Vascular/administración & dosificaciónRESUMEN
Percutaneous delivery of growth factors is often used to treat wounds, and for cosmetic purposes, as a way of accelerating healing and skin regeneration, respectively. However, the therapeutic effects of growth factors are diminished by their poor absorption when delivered percutaneously, in addition to their rapid degradation by proteinases. To overcome these obstacles, we constructed two skin-permeable compounds. Basic fibroblast growth factor (bFGF) and vascular endothelial growth factor-A (VEGF-A) were both genetically paired with low-molecular-weight protamine (LMWP), to yield the compounds LMWP-bFGF and LMWP-VEGF-A, respectively. The molecular weights and N-terminal amino acid sequences of LMWP-bFGF and LMWP-VEGF-A confirmed that the N-terminus-specific conjugation of LMWP with bFGF and VEGF-A had been successful. The biological abilities of the native factors to stimulate human fibroblast (CCD-986sk) and endothelial cell proliferation were preserved. Both compounds significantly promoted wound (scratch) recovery and enhanced procollagen type I C-peptide synthesis in CCD-986sk cells (to levels 184 and 133% those of the native compounds, respectively). The LMWP-conjugated growth factors were significantly more permeable than the native forms (by 7.29- and 29.22-fold, respectively). Finally, encapsulation of the compounds in positively charged elastic nanoliposomes (115 ± 1.54 nm in diameter with a zeta potential of 57.2 ± 3.05 mV) further improved both permeation and stability. Thus, nanoliposomes loaded with LMWP-conjugated growth factors are expected to enhance skin regeneration; the materials will find applications in wound-healing therapies and anti-wrinkle cosmetics.
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Sistemas de Liberación de Medicamentos , Liposomas , Nanocompuestos , Factor A de Crecimiento Endotelial Vascular/administración & dosificación , Cicatrización de Heridas , Humanos , Protaminas , Piel , Absorción Cutánea , Factor A de Crecimiento Endotelial Vascular/farmacocinéticaRESUMEN
We recently developed a therapeutic biopolymer composed of an elastin-like polypeptide (ELP) fused to vascular endothelial growth factor (VEGF) and showed long-term renoprotective effects in experimental renovascular disease after a single intra-renal administration. Here, we sought to determine the specificity, safety, efficacy, and mechanisms of renoprotection of ELP-VEGF after systemic therapy in renovascular disease. We tested whether kidney selectivity of the ELP carrier would reduce off-target binding of VEGF in other organs. In vivo bio-distribution after systemic administration of ELP-VEGF in swine was determined in kidneys, liver, spleen, and heart. Stenotic-kidney renal blood flow and glomerular filtration rate were quantified in vivo using multi-detector computed tomography (CT) after six weeks of renovascular disease, then treated with a single intravenous dose of ELP-VEGF or placebo and observed for four weeks. CT studies were then repeated and the pigs euthanized. Ex vivo studies quantified renal microvascular density (micro-CT) and fibrosis. Kidneys, liver, spleen, and heart were excised to quantify the expression of angiogenic mediators and markers of progenitor cells. ELP-VEGF accumulated predominantly in the kidney and stimulated renal blood flow, glomerular filtration rate, improved cortical microvascular density, and renal fibrosis, and was accompanied by enhanced renal expression of VEGF, downstream mediators of VEGF signaling, and markers of progenitor cells compared to placebo. Expression of angiogenic factors in liver, spleen, and heart were not different compared to placebo-control. Thus, ELP efficiently directs VEGF to the kidney after systemic administration and induces long-term renoprotection without off-target effects, supporting the feasibility and safety of renal therapeutic angiogenesis via systemic administration of a novel kidney-specific bioengineered compound.
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Inductores de la Angiogénesis/farmacología , Riñón/irrigación sanguínea , Riñón/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Péptidos/farmacología , Obstrucción de la Arteria Renal/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/farmacología , Inductores de la Angiogénesis/administración & dosificación , Inductores de la Angiogénesis/farmacocinética , Inductores de la Angiogénesis/toxicidad , Animales , Apoptosis/efectos de los fármacos , Biomarcadores/metabolismo , Modelos Animales de Enfermedad , Portadores de Fármacos , Fibrosis , Tasa de Filtración Glomerular/efectos de los fármacos , Inyecciones Intravenosas , Riñón/metabolismo , Riñón/patología , Péptidos/administración & dosificación , Péptidos/farmacocinética , Péptidos/toxicidad , Proteínas Recombinantes de Fusión/farmacología , Obstrucción de la Arteria Renal/metabolismo , Obstrucción de la Arteria Renal/patología , Obstrucción de la Arteria Renal/fisiopatología , Circulación Renal/efectos de los fármacos , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Sus scrofa , Distribución Tisular , Factor A de Crecimiento Endotelial Vascular/administración & dosificación , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Factor A de Crecimiento Endotelial Vascular/toxicidadRESUMEN
Purpose: To identify the role of the fragment crystallizable (Fc) region in determining intraocular protein drug pharmacokinetics. Methods: We generated a new VEGF-Trap lacking the Fc region (FcfVEGF-Trap, MWt = 100 kDa) by replacing the Fc region of native VEGF-Trap (MWt = 145 kDa) with a dimerized coiled-coil domain. Forty-two rabbits were injected intravitreally with VEGF-Trap or FcfVEGF-Trap (n = 21 each) in one of the eyes, harvested at six time points (1 hour and 1, 2, 4, 14, and 30 days after injections). VEGF-Trap and FcfVEGF-Trap concentrations in the vitreous, aqueous humor, and retina/choroid were measured, and drug pharmacokinetic properties were analyzed. Results: In all three ocular compartments, the maximal concentrations for both FcfVEGF-Trap and VEGF-Trap were observed at 1 hour after injection. Half-lives of FcfVEGF-Trap in the vitreous and retina/choroid (145.02 and 102.12 hours, respectively) were 1.39 and 2.30 times longer than those of VEGF-Trap (103.99 and 44.42 hours, respectively). Total exposure of the aqueous humor and retina/choroid to FcfVEGF-Trap was 13.2% and 39% of the vitreous exposure, respectively, whereas VEGF-Trap concentrations were 25.2% and 26.2%, indicating that FcfVEGF-Trap shows a preference for posterior distribution and elimination. Conclusions: FcfVEGF-Trap, despite its lower molecular weight, showed longer half-lives in vitreous and retina/choroid than VEGF-Trap did, suggesting that Fc receptors in ocular tissues contribute to anti-VEGF drug elimination. Truncation or mutation of the Fc region can prolong the intraocular residence time of VEGF-Trap and possibly reduce the number of VEGF-Trap injections required in clinical practice.
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Inhibidores de la Angiogénesis/farmacocinética , Bevacizumab/farmacocinética , Fragmentos Fc de Inmunoglobulinas/fisiología , Proteínas Recombinantes de Fusión/farmacocinética , Factor A de Crecimiento Endotelial Vascular/farmacocinética , Cuerpo Vítreo/metabolismo , Inhibidores de la Angiogénesis/administración & dosificación , Animales , Humor Acuoso/metabolismo , Bevacizumab/administración & dosificación , Coroides/metabolismo , Semivida , Inyecciones Intravítreas , Modelos Animales , Conejos , Receptores de Factores de Crecimiento Endotelial Vascular/administración & dosificación , Proteínas Recombinantes de Fusión/administración & dosificación , Retina/metabolismoRESUMEN
Nanodiamonds (NDs) represent an emerging class of carbon nanomaterials that possess favorable physical and chemical properties to be used as multifunctional carriers for a variety of bioactive molecules. Here we report the synthesis and characterization of a new injectable ND-based nanocomposite hydrogel which facilitates a controlled release of therapeutic molecules for regenerative applications. In particular, we have formulated a thermosensitive hydrogel using gelatin, chitosan and NDs that provides a sustained release of exogenous human vascular endothelial growth factor (VEGF) for wound healing applications. Addition of NDs improved the mechanical properties of the injectable hydrogels without affecting its thermosensitive gelation properties. Biocompatibility of the generated hydrogel was verified by in vitro assessment of apoptotic gene expressions and anti-inflammatory interleukin productions. NDs were complexed with VEGF and the inclusion of this complex in the hydrogel network enabled the sustained release of the angiogenic growth factor. These results suggest for the first time that NDs can be used to formulate a biocompatible, thermosensitive and multifunctional hydrogel platform that can function both as a filling agent to modulate hydrogel properties, as well as a delivery platform for the controlled release of bioactive molecules and growth factors. STATEMENT OF SIGNIFICANCE: One of the major drawbacks associated with the use of conventional hydrogels as carriers of growth factors is their inability to control the release kinetics of the loaded molecules. In fact, in most cases, a burst release is inevitable leading to diminished therapeutic effects and unsuccessful therapies. As a potential solution to this issue, we hereby propose a strategy of incorporating ND complexes within an injectable hydrogel matrix. The functional groups on the surface of the NDs can establish interactions with the model growth factor VEGF and promote a prolonged release from the polymer network, therefore, providing a longer therapeutic effect. Our strategy demonstrates the efficacy of using NDs as an essential component for the design of a novel injectable nanocomposite system with improved release capabilities.