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2.
Am J Nephrol ; 51(11): 891-902, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33130676

RESUMO

BACKGROUND: Chronic renovascular disease (RVD) can lead to a progressive loss of renal function, and current treatments are inefficient. We designed a fusion of vascular endothelial growth factor (VEGF) conjugated to an elastin-like polypeptide (ELP) carrier protein with an N-terminal kidney-targeting peptide (KTP). We tested the hypothesis that KTP-ELP-VEGF therapy will effectively recover renal function with an improved targeting profile. Further, we aimed to elucidate potential mechanisms driving renal recovery. METHODS: Unilateral RVD was induced in 14 pigs. Six weeks later, renal blood flow (RBF) and glomerular filtration rate (GFR) were quantified by multidetector CT imaging. Pigs then received a single intrarenal injection of KTP-ELP-VEGF or vehicle. CT quantification of renal hemodynamics was repeated 4 weeks later, and then pigs were euthanized. Ex vivo renal microvascular (MV) density and media-to-lumen ratio, macrophage infiltration, and fibrosis were quantified. In parallel, THP-1 human monocytes were differentiated into naïve macrophages (M0) or inflammatory macrophages (M1) and incubated with VEGF, KTP-ELP, KTP-ELP-VEGF, or control media. The mRNA expression of macrophage polarization and angiogenic markers was quantified (qPCR). RESULTS: Intrarenal KTP-ELP-VEGF improved RBF, GFR, and MV density and attenuated MV media-to-lumen ratio and renal fibrosis compared to placebo, accompanied by augmented renal M2 macrophages. In vitro, exposure to VEGF/KTP-ELP-VEGF shifted M0 macrophages to a proangiogenic M2 phenotype while M1s were nonresponsive to VEGF treatment. CONCLUSIONS: Our results support the efficacy of a new renal-specific biologic construct in recovering renal function and suggest that VEGF may directly influence macrophage phenotype as a possible mechanism to improve MV integrity and function in the stenotic kidney.


Assuntos
Proteínas Recombinantes de Fusão/administração & dosagem , Recuperação de Função Fisiológica/efeitos dos fármacos , Obstrução da Artéria Renal/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Animais , Aterosclerose/complicações , Aterosclerose/tratamento farmacológico , Modelos Animais de Doenças , Elastina/administração & dosagem , Elastina/genética , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Humanos , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Rim/fisiologia , Masculino , Microvasos/efeitos dos fármacos , Microvasos/fisiologia , Peptídeos/administração & dosagem , Peptídeos/genética , Proteínas Recombinantes de Fusão/genética , Obstrução da Artéria Renal/etiologia , Circulação Renal/efeitos dos fármacos , Sus scrofa , Fator A de Crescimento do Endotélio Vascular/genética
3.
PLoS One ; 15(4): e0231112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310975

RESUMO

Tissue engineering represents a promising alternative for reconstructive surgical procedures especially for the repair of bone defects that do not regenerate spontaneously. The present study aimed to evaluate the effects of the elastin matrix (E24/50 and E96/37) incorporated with hydroxyapatite (HA) or morphogenetic protein (BMP) on the bone repair process in the distal metaphysis of rat femur. The groups were: control group (CG), hydrolyzed elastin matrix at 50°C/24h (E24/50), E24/50 + HA (E24/50/HA), E24/50 + BMP (E24/50/BMP), hydrolyzed elastin matrix at 37°C/96h (E96/37), E96/37 + HA (E96/37/HA), E96/37 + BMP (E96/37/BMP). Macroscopic and radiographic analyses showed longitudinal integrity of the femur in all groups without fractures or bone deformities. Microtomographically, all groups demonstrated partial closure by mineralized tissue except for the E96/37/HA group with hyperdense thin bridge formation interconnecting the edges of the ruptured cortical. Histologically, there was no complete cortical recovery in any group, but partial closure with trabecular bone. In defects filled with biomaterials, no chronic inflammatory response or foreign body type was observed. The mean volume of new bone formed was statistically significant higher in the E96/37/HA and E24/50 groups (71.28 ± 4.26 and 66.40 ± 3.69, respectively) than all the others. In the confocal analysis, it was observed that all groups presented new bone markings formed during the experimental period, being less evident in the CG group. Von Kossa staining revealed intense calcium deposits distributed in all groups. Qualitative analysis of collagen fibers under polarized light showed a predominance of red-orange birefringence in the newly regenerated bone with no difference between groups. It was concluded that the E24/50 and E96/37/HA groups promoted, with greater speed, the bone repair process in the distal metaphysis of rat femur.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fêmur/lesões , Osteogênese/efeitos dos fármacos , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Proteínas Morfogenéticas Ósseas/administração & dosagem , Modelos Animais de Doenças , Durapatita/administração & dosagem , Elastina/administração & dosagem , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Humanos , Masculino , Ratos , Fatores de Tempo , Microtomografia por Raio-X
4.
Acta Chir Orthop Traumatol Cech ; 86(4): 286-289, 2019.
Artigo em Tcheco | MEDLINE | ID: mdl-31524591

RESUMO

The consequences of deep burns to the hands and face are the most challenging we encounter in modern reconstructive surgery. In many cases, the simple autotransplantation of full-thickness defects with split-thickness skin grafts is now considered inadequate or outdated. For this and many other reasons, the use of dermal substitution is on the rise as it provides improved cosmetic effects and skin compliance, reduces contractility and greatly approximates the histological image to normal, healthy skin. For the purpose of this article, we present a dermal substitution, Matriderm ® , in the case of extensive thermal trauma in a 6-year-old boy. Key words:dermal substitution, burns, Matriderm ® , cutometry.


Assuntos
Queimaduras/fisiopatologia , Queimaduras/terapia , Colágeno/administração & dosagem , Elastina/administração & dosagem , Pele Artificial , Administração Tópica , Criança , Elasticidade , Humanos , Masculino
5.
Am J Physiol Lung Cell Mol Physiol ; 316(4): L608-L620, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30675803

RESUMO

Deterioration of lung functions and degradation of elastin fibers with age are accelerated during chronic obstructive pulmonary disease (COPD). Excessive genesis of soluble elastin peptides (EP) is a key factor in the pathophysiology of COPD. We have previously demonstrated that 6-wk-old mice exhibited emphysematous structural changes associated with proinflammatory immune response after EP instillation. In this study, we investigated the consequences of aging on inflammatory, immune, and histological criteria associated with murine emphysema progression after EP exposure. Young (6 wk old) and elderly (15 mo old) C57BL/6J mice were endotracheally instilled with EP, and, at various time points after treatment, the inflammatory cell profiles from bronchoalveolar lavage fluids (BALF) and the T-lymphocyte phenotypes, at local and systemic levels, were analyzed by flow cytometry. Lungs were also prepared to allow morphological and histological analysis by confocal microscopy. Elderly mice exhibited an earlier development of pulmonary emphysema, characterized by an increase of the inflammatory and lymphocytic infiltrates, extracellular matrix breakdown, and airspace enlargement compared with young mice. This age-dependent parenchymal tissue remodeling was associated with an increase of the matrix metalloproteinase expressions and desmosine levels in BALF and/or sera of EP-treated mice. In addition, both the proportion of CD4+CD28- and CD8+CD28- T cells in the tissues of EP-treated mice and the interferon-γ levels in the EP-specific memory T-cell clones were significantly higher in elderly versus younger mice. This study demonstrates that aging accelerates emphysema development and that this effect is linked to increased EP production and their effects on inflammatory and immune response.


Assuntos
Envelhecimento/imunologia , Envelhecimento/patologia , Enfisema Pulmonar/imunologia , Enfisema Pulmonar/patologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Desmosina/metabolismo , Modelos Animais de Doenças , Elastina/administração & dosagem , Elastina/metabolismo , Feminino , Inflamação/imunologia , Inflamação/patologia , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/patologia , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Neutrófilos/patologia , Proteólise , Enfisema Pulmonar/etiologia
6.
Mol Biol Rep ; 46(1): 261-269, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30421127

RESUMO

Modification of protein-based drug carriers with tumor-targeting properties is an important area of research in the field of anticancer drug delivery. To this end, we developed nanoparticles comprised of elastin-like polypeptides (ELPs) with fused poly-aspartic acid chains (ELP-D) displaying DNA aptamers. DNA aptamers were enzymatically conjugated to the surface of the nanoparticles via genetic incorporation of Gene A* protein into the sequence of the ELP-D fusion protein. Gene A* protein, derived from bacteriophage ϕX174, can form covalent complexes with single-stranded DNA via the latter's recognition sequence. Gene A* protein-displaying nanoparticles exhibited the ability to deliver the anticancer drug paclitaxel (PTX), whilst retaining activity of the conjugated Gene A* protein. PTX-loaded protein nanoparticles displaying DNA aptamers known to bind to the MUC1 tumor marker resulted in increased cytotoxicity with MCF-7 breast cancer cells compared to PTX-loaded protein nanoparticles without the DNA aptamer modification.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Elastina/administração & dosagem , Nanopartículas/uso terapêutico , Antineoplásicos/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Elastina/metabolismo , Feminino , Humanos , Células MCF-7 , Neoplasias/tratamento farmacológico , Paclitaxel/farmacologia
7.
Placenta ; 72-73: 20-27, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30501877

RESUMO

INTRODUCTION: Fusion of therapeutic agents to Elastin-like Polypeptide (ELP) is a novel drug delivery strategy for prevention of placental drug transfer. Previous studies have used a 60 kDa ELP tag for this purpose. However, placental transfer of ELP may be size dependent. The goal of this study was to measure the effects of ELP polymer size on pharmacokinetics, biodistribution, and placental transfer of ELP. METHODS: Three ELPs ranging from 25 to 86 kDa (4.1-6.8 nm hydrodynamic radius) were fluorescently labeled and administered by i.v. bolus to pregnant Sprague Dawley rats on gestational day 14. Plasma levels were monitored for 4 h, organ levels and placental transfer determined by ex vivo fluorescence imaging, and placental localization determined by confocal microscopy. RESULTS: Increasing ELP size resulted in slower plasma clearance and increased deposition in all major maternal organs, except in the kidneys where an opposite effect was observed. Placental levels increased with an increase in size, while in the pups, little to no ELP was detected. DISCUSSION: Pharmacokinetics and biodistribution of ELPs during pregnancy are size dependent, but all ELPs tested were too large to traverse the placental barrier. These studies verify that ELP fusion is a powerful method of modulating half-life and preventing placental transfer of cargo molecules. The tunable nature of the ELP sequence makes it ideal for drug delivery applications during pregnancy, where it can be used to target drugs to the mother while preventing fetal drug exposure.


Assuntos
Biopolímeros/química , Biopolímeros/farmacocinética , Elastina/farmacocinética , Placenta/metabolismo , Animais , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Elastina/administração & dosagem , Elastina/análise , Feminino , Rim/química , Microscopia Confocal , Modelos Animais , Peptídeos/análise , Peptídeos/farmacocinética , Placenta/química , Gravidez , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Distribuição Tecidual
8.
J Control Release ; 283: 94-104, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-29778783

RESUMO

Age-related macular degeneration (AMD) is the leading cause of severe and irreversible central vision loss, and the primary site of AMD pathology is the retinal pigment epithelium (RPE). Geographic atrophy (GA) is an advanced form of AMD characterized by extensive RPE cell loss, subsequent degeneration of photoreceptors, and thinning of retina. This report describes the protective potential of a peptide derived from the αB crystallin protein using a sodium iodate (NaIO3) induced mouse model of GA. Systemic NaIO3 challenge causes degeneration of the RPE and neighboring photoreceptors, which have similarities to retinas of GA patients. αB crystallin is an abundant ocular protein that maintains ocular clarity and retinal homeostasis, and a small peptide from this protein (mini cry) displays neuroprotective properties. To retain this peptide for longer in the vitreous, mini cry was fused to an elastin-like polypeptide (ELP). A single intra-vitreal treatment by this crySI fusion significantly inhibits retinal degeneration in comparison to free mini cry. While mini cry is cleared from the eye with a mean residence time of 0.4 days, crySI is retained with a mean residence time of 3.0 days; furthermore, fundus photography reveals evidence of retention at two weeks. Unlike the free mini cry, crySI protects the RPE against NaIO3 challenge for at least two weeks after administration. CrySI also inhibits RPE apoptosis and caspase-3 activation and protects the retina from cell death up to 1-month post NaIO3 challenge. These results show that intra-ocular ELP-linked peptides such as crySI hold promise as protective agents to prevent RPE atrophy and progressive retinal degeneration in AMD.


Assuntos
Elastina/administração & dosagem , Degeneração Macular/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Peptídeos/administração & dosagem , Cadeia B de alfa-Cristalina/administração & dosagem , Animais , Modelos Animais de Doenças , Elastina/farmacocinética , Olho/efeitos dos fármacos , Olho/metabolismo , Olho/patologia , Injeções Intravítreas , Iodatos , Degeneração Macular/induzido quimicamente , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Camundongos , Neuroproteção , Fármacos Neuroprotetores/farmacocinética , Peptídeos/farmacocinética , Cadeia B de alfa-Cristalina/farmacocinética
9.
J Control Release ; 277: 154-164, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29551712

RESUMO

Fibroblast growth factor 21 (FGF21) is under investigation as a type 2 diabetes protein drug, but its efficacy is impeded by rapid in vivo clearance and by costly production methods. To improve the protein's therapeutic utility, we recombinantly expressed FGF21 as a fusion with an elastin-like polypeptide (ELP), a peptide polymer that exhibits reversible thermal phase behavior. Below a critical temperature, ELPs exist as miscible unimers, while above, they associate into a coacervate. The thermal responsiveness of ELPs is retained upon fusion to proteins, which has notable consequences for the production and in vivo delivery of FGF21. First, the ELP acts as a solubility enhancer during E. coli expression, yielding active fusion protein from the soluble cell lysate fraction and eliminating the protein refolding steps that are required for purification of FGF21 from inclusion bodies. Second, the ELP's phase transition behavior is exploited for facile chromatography-free purification of the ELP-FGF21 fusion. Third, the composition and molecular weight of the ELP are designed such that the ELP-FGF21 fusion undergoes a phase transition triggered solely by body heat, resulting in an immiscible viscous phase upon subcutaneous (s.c.) injection and thereby creating an injectable depot. Indeed, a single s.c. injection of ELP-FGF21 affords up to five days of sustained glycemic control in ob/ob mice. The ELP fusion partner massively streamlines production and purification of FGF21, while providing a controlled release method for delivery that reduces the frequency of injection, thereby enhancing the pharmacological properties of FGF21 as a protein drug to treat metabolic disease.


Assuntos
Biopolímeros/metabolismo , Diabetes Mellitus Experimental/metabolismo , Elastina/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Temperatura Alta , Hipoglicemiantes/metabolismo , Células 3T3 , Animais , Biopolímeros/administração & dosagem , Biopolímeros/química , Temperatura Corporal/fisiologia , Preparações de Ação Retardada , Diabetes Mellitus Experimental/tratamento farmacológico , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos/métodos , Elastina/administração & dosagem , Elastina/química , Fatores de Crescimento de Fibroblastos/administração & dosagem , Fatores de Crescimento de Fibroblastos/química , Células HEK293 , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Masculino , Camundongos , Camundongos Obesos , Distribuição Aleatória
11.
Unfallchirurg ; 121(3): 256-260, 2018 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-29322228

RESUMO

This case report describes a 55-year-old male patient with type II necrotizing fasciitis (NF) of the hand and forearm. The rapid progression of the tissue infection could be successfully stopped with radical surgical débridement and antibiotic therapy. For the reconstruction of the extensive loss of soft tissue a combination of split-thickness skin graft (STSG) and the synthetic dermal substitute MatriDerm® was used. In cases of NF, MatriDerm® and STSG provide a rapidly available and simple alternative to other reconstruction techniques.


Assuntos
Colágeno/administração & dosagem , Elastina/administração & dosagem , Fasciite Necrosante/cirurgia , Transplante de Pele , Pele Artificial , Infecções dos Tecidos Moles/cirurgia , Antibacterianos/uso terapêutico , Desbridamento , Fasciite Necrosante/tratamento farmacológico , Antebraço , Mãos , Humanos , Masculino , Pessoa de Meia-Idade , Infecções dos Tecidos Moles/tratamento farmacológico
12.
Artif Organs ; 42(6): E102-E113, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29266271

RESUMO

When ligaments are injured, reconstructive surgery is sometimes required to restore function. Methods of reconstructive surgery include transplantation of an artificial ligament and autotransplantation of a tendon. However, these methods have limitations related to the strength of the bone-ligament insertion and biocompatibility of the transplanted tissue after surgery. Therefore, it is necessary to develop new reconstruction methods and pursue the development of artificial ligaments. Elastin is a major component of elastic fibers and ligaments. However, the role of elastin in ligament regeneration has not been described. Here, we developed a rabbit model of a medial collateral ligament (MCL) rupture and treated animal knees with exogenous elastin [100 µg/(0.5 mL·week)] for 6 or 12 weeks. Elastin treatment increased gene expression and protein content of collagen and elastin (gene expression, 6-fold and 42-fold, respectively; protein content, 1.6-fold and 1.9-fold, respectively), and also increased the elastic modulus of MCL increased with elastin treatment (2-fold) compared with the controls. Our data suggest that elastin is involved in the regeneration of damaged ligaments.


Assuntos
Ligamentos Colaterais/lesões , Elastina/uso terapêutico , Traumatismos do Joelho/terapia , Regeneração , Animais , Ligamentos Colaterais/efeitos dos fármacos , Ligamentos Colaterais/patologia , Ligamentos Colaterais/fisiologia , Módulo de Elasticidade/efeitos dos fármacos , Elastina/administração & dosagem , Feminino , Colágenos Fibrilares/análise , Colágenos Fibrilares/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Traumatismos do Joelho/genética , Traumatismos do Joelho/patologia , Coelhos , Regeneração/efeitos dos fármacos , Engenharia Tecidual
13.
Biomaterials ; 141: 149-160, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28688286

RESUMO

Growth factor therapy is a promising approach for chronic diabetic wounds, but strategies to efficiently and cost-effectively deliver active molecules to the highly proteolytic wound environment remain as major obstacles. Here, we re-engineered keratinocyte growth factor (KGF) and the cellular protective peptide ARA290 into a protein polymer suspension with the purpose of increasing their proteolytic resistance, thus their activity in vivo. KGF and ARA290 were fused with elastin-like peptide (ELP), a protein polymer derived from tropoelastin, that confers the ability to separate into a colloidal suspension of liquid-like coacervates. ELP fusion did not diminish peptides activities as demonstrated by ability of KGF-ELP to accelerate keratinocyte proliferation and migration, and ARA290-ELP to protect cells from apoptosis. We examined the healing effect of ARA290-ELP and KGF-ELP alone or in combination, in a full-thickness diabetic wound model. In this model, ARA290-ELP was found to accelerate healing, notably by increasing angiogenesis in the wound bed. We further showed that co-delivery of ARA290 and KGF, with the 1:4 KGF-ELP to ARA290-ELP ratio, was the most effective wound treatment with the fastest healing rate, the thicker granulation tissue and regenerated epidermis after 28 days. Overall, this study shows that ARA290-ELP and KGF-ELP constitute promising new therapeutics for treatment of chronic wounds.


Assuntos
Indutores da Angiogênese/uso terapêutico , Diabetes Mellitus Experimental/complicações , Elastina/uso terapêutico , Fator 7 de Crescimento de Fibroblastos/uso terapêutico , Oligopeptídeos/uso terapêutico , Cicatrização/efeitos dos fármacos , Indutores da Angiogênese/administração & dosagem , Animais , Linhagem Celular , Elastina/administração & dosagem , Fator 7 de Crescimento de Fibroblastos/administração & dosagem , Humanos , Camundongos , Oligopeptídeos/administração & dosagem , Proteólise , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/uso terapêutico
14.
J Drug Target ; 25(6): 523-531, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28140690

RESUMO

Notch pathway was found to be activated in most glioblastomas (GBMs), underlining the importance of Notch in formation and recurrence of GBM. In this study, a Notch inhibitory peptide, dominant negative MAML (dnMAML), was conjugated to elastin-like polypeptide (ELP) for tumor targeted delivery. ELP is a thermally responsive polypeptide that can be actively and passively targeted to the tumor site by localized application of hyperthermia. This complex was further modified with the addition of a cell penetrating peptide, SynB1, for improved cellular uptake and blood-brain barrier penetration. The SynB1-ELP1-dnMAML was examined for its cellular uptake, cytotoxicity, apoptosis, cell cycle inhibition and the inhibition of target genes' expression. SynB1-ELP1-dnMAML inhibited the growth of D54 and U251 cells by inducing apoptosis and cell cycle arrest, especially in the presence of hyperthermia. Hyperthermia increased overall uptake of the polypeptide by the cells and enhanced the resulting pharmacological effects of dnMAML, showing the inhibition of targets of Notch pathway such as Hes-1 and Hey-L. These results confirm that dnMAML is an effective Notch inhibitor and combination with ELP may allow thermal targeting of the SynB1-ELP1-dnMAML complex in cancer cells while avoiding the dangers of systemic Notch inhibition.


Assuntos
Peptídeos Penetradores de Células/administração & dosagem , Proteínas de Ligação a DNA/administração & dosagem , Glioblastoma/tratamento farmacológico , Receptores Notch/antagonistas & inibidores , Fatores de Transcrição/administração & dosagem , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/farmacologia , Proteínas de Ligação a DNA/farmacocinética , Proteínas de Ligação a DNA/farmacologia , Sistemas de Liberação de Medicamentos , Elastina/administração & dosagem , Glioblastoma/patologia , Humanos , Hipertermia Induzida/métodos , Peptídeos/administração & dosagem , Fatores de Transcrição/farmacocinética , Fatores de Transcrição/farmacologia
15.
J Burn Care Res ; 38(5): e859-e867, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28221299

RESUMO

Tropoelastin (TE), the soluble precursor of insoluble elastin fibers, is produced in minimal amounts in adults. Burn injuries result in inflexible collagen-rich scars because of lack of elastin fiber formation. We studied the feasibility of using recombinant human tropoelastin to enable elastin fiber production in burn and surgical scars to improve skin flexibility. In a swine hypertrophic burn scar model, normal skin and 3 × 3-cm partial thickness thermal burns underwent dermatome resection at 1 week post burn and randomized to four subcutaneous injections of saline or TE (either 0.5, 5, or 10 mg/ml) spaced 3 days apart. Two burn sites received TE injections after wound closure (0.5 or 10 mg/ml). At 90 days, skin hardness, flexibility, and histology were evaluated. All injury sites developed hypertrophic scars. New elastin fibers were found in burn scars in all injuries injected after skin closure with low (5/5) and high (6/6) TE doses (P < .05). No elastin fibers were observed without TE treatment. No significant differences in skin hardness, flexibility, or inflammation were observed. This is the first report demonstrating that subcutaneous injections of TE into surgical and burn injuries can safely produce new elastin fibers in scars. Despite the development of new elastin fibers, skin flexibility was not improved, possibly because of insufficient elastin fiber maturation or the hypertrophic model used. The ability to restore elastin fiber formation in adult skin after burns, trauma, and surgery may improve skin regeneration and reduce disabling complications of scar formation.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Cicatriz Hipertrófica/tratamento farmacológico , Elastina/administração & dosagem , Hipertrofia/tratamento farmacológico , Tropoelastina/administração & dosagem , Animais , Queimaduras , Modelos Animais de Doenças , Humanos , Proteínas Recombinantes , Transplante de Pele/estatística & dados numéricos , Suínos , Cicatrização/efeitos dos fármacos
16.
Theranostics ; 6(12): 2235-2249, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27924160

RESUMO

Elastin-like polypeptide (ELP)-based drug delivery has been utilized for various applications including cancer therapies for many years. Genetic incorporation of internalization ligands and cell-targeting peptides along with ELP polymer enhanced tumor accumulation and retention time as well as stability and activities of the drug conjugates. Herein, we described a unique delivery system comprised of genetically engineered ELP incorporated with multiple copies of IL-4 receptor targeting peptide (AP1) periodically and proapoptotic peptide (KLAKLAK)2 referred to as AP1-ELP-KLAK. It triggered thermal-responsive self-assembly into a nanoparticle-like structure at physiological body temperature and stabilized its helical conformation, which is critical for its membrane-disrupting activities. Increased IL-4 receptor specific cellular internalization was associated with the enhanced cytotoxic effect of (KLAKLAK)2 peptide. Additionally, multivalent presentation of targeting ligands by AP1-ELP-KLAK significantly enhanced intratumoral localization and prolonged the retention time compared to ELP-KLAK, non-targeted control. Systemic administration of AP1-ELP-KLAK significantly inhibited tumor growth by provoking cell apoptosis in various tumor xenograft models without any specific organ toxicity. Thus, our newly designed AP1-ELP-KLAK polymer nanoparticle is a promising candidate for effective cancer therapy and due to the simple preparative procedures of ELPs, this platform can be used as a good carrier for tumor-specific delivery of other therapeutics.


Assuntos
Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Antineoplásicos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Elastina/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias/terapia , Peptídeos/administração & dosagem , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Elastina/metabolismo , Feminino , Xenoenxertos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Peptídeos/metabolismo , Multimerização Proteica , Resultado do Tratamento
17.
Mol Pharm ; 13(5): 1528-39, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-26998616

RESUMO

Monitoring of drug release from a heat-activated liposome carrier provides an opportunity for real-time control of drug delivery and allows prediction of the therapeutic effect. We have developed short-chain elastin-like polypeptide-incorporating thermosensitive liposomes (STLs). Here, we report the development of STL encapsulating gadobenate dimeglumine (Gd-BOPTA), a MRI contrast agent, and doxorubicin (Dox) (Gd-Dox-STL). The Dox release profile from Gd-Dox-STL was comparable to Gd-Dox-LTSL; however, the serum stability of Gd-Dox-STL was much higher than Gd-Dox-LTSL. MRI studies showed that the difference in T1 relaxation time between 37 and 42 °C for Gd-Dox-STL was larger than the difference for Gd-Dox-LTSL. Although relaxivity for both liposomes at 42 °C was similar, the relaxivity of Gd-Dox-STL at 37 °C was 2.5-fold lower than that of Gd-Dox-LTSL. This was likely due to Gd-BOPTA leakage from the LTSL because of low stability at 37 °C. Pharmacokinetic studies showed plasma half-lives of 4.85 and 1.95 h for Gd-Dox-STL and Gd-Dox-LTSL, respectively, consistent with in vitro stability data. In vivo MRI experiments demonstrated corelease of Dox and Gd-BOPTA from STL under mild hyperthermia induced by high-intensity focused ultrasound (HIFU), which suggests STL is a promising tumor selective formulation when coupled with MR-guided HIFU.


Assuntos
Antineoplásicos/administração & dosagem , Lipossomos/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Meios de Contraste/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/fisiologia , Elastina/administração & dosagem , Meia-Vida , Temperatura Alta , Hipertermia Induzida/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Meglumina/administração & dosagem , Meglumina/análogos & derivados , Meglumina/farmacocinética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/farmacocinética , Peptídeos/administração & dosagem , Temperatura , Ultrassonografia/métodos
18.
J Control Release ; 240: 93-108, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-26578439

RESUMO

Elastin-like polypeptides (ELPs) constitute a genetically engineered class of 'protein polymers' derived from human tropoelastin. They exhibit a reversible phase separation whereby samples remain soluble below a transition temperature (Tt) but form amorphous coacervates above Tt. Their phase behavior has many possible applications in purification, sensing, activation, and nanoassembly. As humanized polypeptides, they are non-immunogenic, substrates for proteolytic biodegradation, and can be decorated with pharmacologically active peptides, proteins, and small molecules. Recombinant synthesis additionally allows precise control over ELP architecture and molecular weight, resulting in protein polymers with uniform physicochemical properties suited to the design of multifunctional biologics. As such, ELPs have been employed for various uses including as anti-cancer agents, ocular drug delivery vehicles, and protein trafficking modulators. This review aims to offer the reader a catalogue of ELPs, their various applications, and potential for commercialization across a broad spectrum of fields.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Elastina/administração & dosagem , Nanomedicina/métodos , Peptídeos/administração & dosagem , Administração Oftálmica , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Sistemas de Liberação de Medicamentos/tendências , Elastina/química , Elastina/metabolismo , Humanos , Nanomedicina/tendências , Peptídeos/química , Peptídeos/metabolismo
19.
J Ocul Pharmacol Ther ; 32(3): 163-71, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26672799

RESUMO

PURPOSE: Elastin-like polypeptide (ELP) is a bioengineered protein widely applied as a drug carrier due to its biocompatibility and amenability to modification with cell-penetrating peptides (CPPs) and therapeutic agents. The purpose of this study was to determine whether topically applied ELP or CPP-fused ELPs penetrate the corneal barrier. METHODS: In vitro binding and cytotoxicity to human corneal epithelial (HCE) cells were determined for ELP or CPP-ELPs. Corneal binding, clearance, and penetration were assessed in a rabbit model following topical application of the fluorescently labeled proteins by quantitative fluorescence imaging and histology. RESULTS: ELP bound to HCE cells in vitro, and binding/uptake was enhanced 2- to 3-fold by the addition of CPPs. When applied topically to rabbit eyes, ELP accumulated in the cornea at levels 7.4-fold higher than did an equivalent dose of immunoglobulin G. Both ELP and a CPP-ELP penetrated the corneal epithelium and were detectable in the stroma. Addition of CPPs to ELP, however, did not significantly enhance corneal uptake or penetration in vivo relative to ELP alone. The polypeptides cleared from the cornea over a period of 20-30 min after application, after which cornea levels reached a steady state of 15-30 µg/mL for up to 3 h. CONCLUSIONS: The ELP drug carrier can penetrate the corneal epithelium and accumulate in the stroma. Given its amenability for fusion to multiple types of therapeutic agents, ELP has the potential to serve as a drug carrier for topical ocular applications.


Assuntos
Peptídeos Penetradores de Células/farmacocinética , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Elastina/farmacocinética , Epitélio Corneano/efeitos dos fármacos , Animais , Western Blotting , Proliferação de Células/efeitos dos fármacos , Peptídeos Penetradores de Células/administração & dosagem , Células Cultivadas , Elastina/administração & dosagem , Epitélio Corneano/citologia , Epitélio Corneano/metabolismo , Citometria de Fluxo , Humanos , Cinética , Microscopia de Fluorescência , Coelhos , Distribuição Tecidual
20.
Gastrointest Endosc ; 82(5): 944-52, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26092617

RESUMO

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) can successfully resect large lesions en bloc by using a submucosal injection solution, but the cost of currently available submucosal injection solutions is not satisfactory. The authors' aim was to evaluate the feasibility and effectiveness of a thermally sensitive elastin-like polypeptide (ELP) used as submucosal injection solution in ESD. METHODS: We conducted an ex vivo study to determine the optimal concentration of ELPs in rabbits, an in vivo study to evaluate the effectiveness of mucosal elevation in rats, and a large animal study to confirm the feasibility of preclinical application by using conventional clinical procedure in pigs. RESULTS: ELP (500 µM) was proved to be the optimal injectable submucosal injection solution and elevated mucosa more efficiently than any control. The same concentration of ELP exhibited an equivalent effectiveness of mucosal elevation, the retention of the elevation, and minimal bleeding with sodium hyaluronate. The ESD procedure time with 500 µM ELP in a preclinical study with pigs was significantly shorter than with any other concentration of ELP and normal saline solution. CONCLUSIONS: Use of ELP as submucosal injection solution was feasible, with higher and longer-lasting elevation and fewer adverse events.


Assuntos
Dissecação/métodos , Elastina/administração & dosagem , Endoscopia Gastrointestinal/métodos , Mucosa Gástrica/cirurgia , Neoplasias Experimentais , Neoplasias Gástricas/terapia , Animais , Modelos Animais de Doenças , Elastina/química , Estudos de Viabilidade , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Injeções Intralesionais , Masculino , Coelhos , Ratos , Ratos Sprague-Dawley , Neoplasias Gástricas/patologia , Suínos , Porco Miniatura , Temperatura , Resultado do Tratamento
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