ABSTRACT
Type 1 diabetes mellitus (T1DM) is a chronic disease affecting millions worldwide. Insulin therapy is currently the golden standard for treating T1DM; however, it does not restore the normal glycaemic balance entirely, which increases the risk of secondary complications. Beta-cell therapy may be a possible way of curing T1DM and has already shown promising results in the clinic. However, low retention rates, poor cell survival, and limited therapeutic potential are ongoing challenges, thus increasing the need for better cell encapsulation devices. This study aimed to develop a mechanically reinforced vascular endothelial growth factor (VEGF)-delivering encapsulation device suitable for beta cell encapsulation and transplantation. Poly(l-lactide-co-ε-caprolactone) (PLCL)/gelatin methacryloyl (GelMA)/alginate coaxial nanofibres were produced using electrospinning and embedded in an alginate hydrogel. The encapsulation device was physically and biologically characterised and was found to be suitable for INS-1E beta cell encapsulation, vascularization, and transplantation in terms of its biocompatibility, porosity, swelling ratio and mechanical properties. Lastly, VEGF was incorporated into the hydrogel and the release kinetics and functional studies revealed a sustained release of bioactive VEGF for at least 14 days, making the modified alginate system a promising candidate for improving the beta cell survival after transplantation.
Subject(s)
Alginates , Gelatin , Hydrogels , Insulin-Secreting Cells , Vascular Endothelial Growth Factor A , Hydrogels/chemistry , Alginates/chemistry , Insulin-Secreting Cells/metabolism , Insulin-Secreting Cells/cytology , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor A/administration & dosage , Gelatin/chemistry , Animals , Polyesters/chemistry , Rats , Cell Survival/drug effects , Humans , Diabetes Mellitus, Type 1/therapy , Methacrylates/chemistry , Angiogenesis Inducing Agents/chemistry , Angiogenesis Inducing Agents/pharmacology , Angiogenesis Inducing Agents/administration & dosage , Surface PropertiesABSTRACT
Ischemic heart diseases such as myocardial infarction (MI) are a global health problem and a leading cause of mortality worldwide. Angiogenesis is an important approach for myocardial healing following ischemia. Thus, this study aimed to explore the potential cardiac angiogenic effects of selenium (Se), alone and in combination with the tumor necrosis factor-alpha inhibitor, pentoxifylline (PTXF), via Akt/HIF-1α signaling. MI was induced in rats using two subcutaneous doses of isoprenaline (ISP) at a 24-h interval (150 mg/kg). One week later, rats were orally given Se (150 µg/kg/day), PTXF (50 mg/kg/day), or Se/PTXF combination. ISP-induced myocardial damage was evident by increased HW/TL ratios, ST segment elevation, and increased serum levels of CK-MB, LDH, and troponin-I. ISP increased the cardiac levels of the lipid peroxidation marker MDA; the pro-inflammatory cytokines IL-6, IL-1ß, and TNF-α; and the pro-apoptotic protein Bax and caspase-3. In contrast, the cardiac levels of the antioxidant markers GSH and SOD and the anti-apoptotic marker Bcl-2 were reduced. Furthermore, ISP markedly increased the cardiac levels of p-Akt and HIF-1α proteins and the cardiac gene expression of ANGPT-1, VEGF, and FGF-2. Treatment with Se both alone and in combination with PTXF ameliorated the ISP-induced myocardial damage and further increased cardiac angiogenesis via Akt/HIF-1α signaling. Se/PTXF combined therapy was more beneficial than individual treatments. Our study revealed for the first time the cardiac angiogenic effects of Se both alone and in combination with PTXF in myocardial infarction, suggesting that both may be promising candidates for clinical studies.
Subject(s)
Disease Models, Animal , Hypoxia-Inducible Factor 1, alpha Subunit , Myocardial Infarction , Neovascularization, Physiologic , Pentoxifylline , Proto-Oncogene Proteins c-akt , Selenium , Signal Transduction , Animals , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Myocardial Infarction/drug therapy , Myocardial Infarction/pathology , Myocardial Infarction/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Selenium/pharmacology , Selenium/administration & dosage , Male , Signal Transduction/drug effects , Neovascularization, Physiologic/drug effects , Pentoxifylline/pharmacology , Pentoxifylline/administration & dosage , Pentoxifylline/therapeutic use , Rats, Wistar , Rats , Myocardium/metabolism , Myocardium/pathology , Drug Therapy, Combination , Angiogenesis Inducing Agents/pharmacology , Angiogenesis Inducing Agents/administration & dosage , Isoproterenol , Tumor Necrosis Factor-alpha/metabolism , AngiogenesisABSTRACT
BACKGROUND: Leptin, the cytokine produced by white adipose tissue is known to regulate food energy homeostasis through its hypothalamic receptor. In vitro studies have demonstrated that leptin plays a major role in angiogenesis through binding to the receptor Ob-R present on ECs by stimulating and initiating new capillary like structures from ECs. Various in vivo studies indicate that leptin has diverse effect on angiogenesis. A few reports have showed that leptin exerts pro angiogenic effects while some suggested that it has antiangiogenic potential. It is theoretically highly important to understand the effect of leptin on angiogenesis to use as a therapeutic molecule in various angiogenesis related pathological conditions. Chicken chorio allantoic membrane (CAM) on 9th day of incubation was incubated with 1, 3 and 5 µg concentration of HRL for 72 h using gelatin sponge. Images where taken after every 24 h of incubation and analysed with Angioguant software. The treated area was observed under microscope and histological evaluation was performed for the same. Tissue thickness was calculated morphometrically from haematoxylin and eosin stained cross sections. Reverse transcriptase PCR and immunohistochemistry were also performed to study the gene and protein level expression of angiogenic molecules. RESULTS: HRL has the ability to induce new vessel formation at the treated area and growth of the newly formed vessels and cellular morphological changes occur in a dose dependent manner. Increase in the tissue thickness at the treated area is suggestive of initiation of new capillary like structures. Elevated mRNA and protein level expression of VEGF165 and MMP2 along with the activation of ECs as demonstrated by the presence of CD34 expression supports the neovascularization potential of HRL. CONCLUSION: Angiogenic potential of HRL depends on the concentration and time of incubation and is involved in the activation of ECs along with the major interaction of VEGF 165 and MMP2. It is also observed that 3 µg of HRL exhibits maximum angiogenic potential at 72 h of incubation. Thus our data suggest that dose dependent angiogenic potential HRL could provide a novel role in angiogenic dependent therapeutics such as ischemia and wound healing conditions.
Subject(s)
Humans , Animals , Chick Embryo , Zygote , Neovascularization, Physiologic/drug effects , Leptin/administration & dosage , Endothelial Cells/drug effects , Angiogenesis Inducing Agents/administration & dosage , Chorioallantoic Membrane/drug effects , Recombinant Proteins/pharmacology , RNA, Messenger/metabolism , Immunohistochemistry , Gelatinases/metabolism , Antigens, CD34/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Matrix Metalloproteinase 2/metabolism , Vascular Endothelial Growth Factor A/metabolism , Chorioallantoic Membrane/enzymology , Chorioallantoic Membrane/blood supply , Dose-Response Relationship, Drug , MicroscopyABSTRACT
OBJETIVO: Avaliar a segurança, viabilidade e efeitos iniciais, clínicos e sobre a perfusão miocárdica, da administração intramiocárdica, transtorácica, de VEGF 165 plasmidial em pacientes com doença arterial coronariana avançada e angina refratária, não passíveis de revascularização percutânea e cirúrgica. MÉTODOS: Ensaio clínico fase I/II. Treze pacientes cardiopatas isquêmicos com angina refratária apesar de tratamento medicamentoso máximo por no mínimo seis meses, não passíveis de revascularização cirúrgica ou por cateter foram submetidos a injeções intramiocárdicas de 2000µg VEGF 165 plasmidial. Os pacientes foram avaliados por cintilografia miocárdica, teste ergométrico, questionário de qualidade de vida (Minnesota) e determinação das classes de insuficiência cardíaca (NYHA) e angina (CCS). RESULTADOS: Não houve óbitos ou reintervenções. Durante o período de tratamento medicamentoso máximo, não se observou diferenças em cintilografias miocárdicas, testes ergométricos e questionários de qualidade de vida, ainda, houve tendência a piora das classes NYHA (P=0,05) e CCS (P=0,05). Três meses após intervenção, observou-se melhora dos escores cintilográficos SSS (18,38±7,51 vs. 15,31±7,29, P=0,003) e SRS (11,92±7,49 vs. 8,53±6,68, P=0,002), porém não na proporção da extensão da área de miocárdio isquêmico (23,38±13,12 por cento vs. 20,08±13,88 por cento, P=0,1). Houve tendência a melhora dos METs nas ergometrias (7,66±4,47 vs. 10,29±4,36, P=0,08), melhora do escore de qualidade de vida (48,23±18,35 vs. 30,15±20,13; P=0,02) e das classes NYHA (3,15±0,38 vs. 1,77±0,83, P=0,001) e CCS (3,08±0,64 vs. 1,77±0,83, P=0,001), no mesmo período. CONCLUSÕES: A terapia demonstrou-se segura e viável nesta série de pacientes. Os resultados iniciais tendem a demonstrar melhora na gravidade da angina e redução da intensidade da isquemia miocárdica.
OBJECTIVE: Safety, feasibility and early myocardial angiogenic effects evaluation of transthoracic intramyocardial phVEGF165 administration for refractory angina in no option patients. METHODS: Cohort study, in which 13 patients with refractory angina under optimized clinical treatment where included, after cineangiograms had been evaluated and found unfeasible by surgeon and interventional cardiologist. Intramyocardial injections of 5mL solution containing plasmidial VEGF165 where done over the ischemic area of myocardium identified by previous SPECT/Sestamibi scan. Evaluations included a SPECT scan, stress test, Minnesotta QOL questionnaire and NYHA functional class and CCS angina class determinations. RESULTS: There were no deaths or new interventions during the study period. There were no significant variations in SPECT scans, QOL scores and stress tests results during medical treatment in the included patients. After the 3rd post operative month, there was improvement in SPECT segmental scores, SSS (18.38±7.51 vs. 15.31±7.29, P=0.003) and SRS (11.92±7.49 vs. 8.53±6.68, P=0.002). The ischemic area extension, however, had non-significant variation (23.38±13.12 percent vs. 20.08±13.88 percent, P=0.1). Stress tests METs varied from 7.66±4.47 pre to 10.29±4.36 METs post-op (P=0.08). QOL score improved from 48.23±18.35 pre to 30.15±20.13 post-op points (P=0.02). NYHA class was 3.15±0.38 pre vs. 1.77±0.83 post-op (P=0.001) and angina CCS class, 3.08±0.64 vs. 1.77±0.83 (P=0.001). CONCLUSIONS: Intramyocardial VEGF165 therapy for refractory angina, in this small trial of no option patients, resulted feasible and safe. Early clinical and scintilographic data showed improvements in symptoms and myocardial perfusion, with regression of ischemia severity in treated areas.
Subject(s)
Female , Humans , Male , Middle Aged , Angina Pectoris/therapy , Angiogenesis Inducing Agents/administration & dosage , Genetic Therapy/methods , Myocardial Ischemia/therapy , Vascular Endothelial Growth Factor A/administration & dosage , Vascular Endothelial Growth Factor A/genetics , Angiogenesis Inducing Agents/adverse effects , Plasmids/administration & dosage , Severity of Illness Index , Treatment Outcome , Vascular Endothelial Growth Factor A/adverse effectsABSTRACT
Introducción. El crecimiento tumoral es mayor después de la cirugía abierta que tras la laparoscopia en estudios experimentales. La interleucina (IL) 6 y la IL-1 son citocinas proinflamatorias cuya expresión aumenta más después de una laparotomía que tras una laparoscopia. In vitro, la IL-6 y la IL-1Beta estimulan la expresión de factores angiogénicos como el factor de crecimiento del endotelio vascular y la ciclooxigenasa-2. Hipótesis: el marcado aumento de citocinas proinflamatorias tras cirugía abierta estímula en mayor medida la angiogénesis y el crecimiento tumoral. Métodos. Inducimos un tumor sólido en ratones mediante inyección de 5 106 células en la pared cecal. Los ratones fueron aleatorizados en resección cecal abierta y resección por laparoscopia. La IL-6, la IL-1Beta y el factor de crecimiento del endotelio vascular se determinaron en suero durante el postoperatorio. Los animales se sacrificaron 12 días después. Se aplicó una puntuación a la recidiva tumoral en función de su extensión y se determinó el peso total del tumor. La densidad microvascular y la expresión de la ciclooxigenasa-2 se estudiaron mediante inmunohistoquímica. Resultados. La puntuación y el peso del tumor fueron mayores en el grupo de resección cecal abierta (p < 0,01). Los valores séricos de IL-6 (4.157 ñ 1.297 frente a 2.514 ñ 1.417 pg/ml, en los grupos de resección cecal abierta y resección por laparoscopia, respectivamente) y factor de crecimiento del endotelio vascular (231 ñ 125 frente a 45 ñ 9 pg/ml, en los grupos de resección cecal abierta y resección por laparoscopia, respectivamente) fueron mayores en el grupo de resección cecal abierta (p < 0,01). La angiogénesis estaba aumentada en el grupo de resección cecal abierta. La densidad microvascular media ñ desviación estándar fue de 34,3 ñ 11,5 en el grupo de resección cecal abierta frente a 15,5 ñ 12,5 en el de resección por laparoscopia (p < 0,01). La expresión de ciclooxigenasa-2 también era mayor en el grupo de resección cecal abierta. Los valores séricos de IL-6 se correlacionaron con los del factor de crecimiento del endotelio vascular (rho = 0,61; p < 0,001). A su vez, los valores de factor de crecimiento del endotelio vascular se correlacionaron con la densidad microvascular y con el peso tumoral (rho = 0,63; p < 0,001). Conclusiones. El aumento de citocinas proinflamatorias tras la cirugía abierta se asocia con una mayor angiogénesis y un mayor crecimiento tumoral, en comparación con la cirugía laparoscópica en ratones (AU)
Subject(s)
Animals , Mice , Disease Models, Animal , Laparotomy/methods , Interleukin-6/administration & dosage , Interleukin-6/therapeutic use , Interleukin-1/administration & dosage , Interleukin-1/therapeutic use , Immunohistochemistry/methods , Colonic Neoplasms/complications , Colonic Neoplasms/diagnosis , Colonic Neoplasms/surgery , Laparoscopy/methods , Angiogenesis Inducing Agents/administration & dosage , Cytokines/administration & dosage , Cytokines/therapeutic use , Cell Line/cytology , Cell Line/pathology , Angiogenesis Inducing Agents/therapeutic useABSTRACT
No disponible
Subject(s)
Synovitis/diagnosis , Synovitis/therapy , Arthroscopy/methods , Angiogenesis Inducing Agents/administration & dosage , Angiogenesis Inducing Agents/analysis , Fibroblast Growth Factors/administration & dosage , Biopsy/methods , Hyperplasia/diagnosis , Hyperplasia/complications , Angiogenesis Inducing Agents/immunologyABSTRACT
No disponible
Subject(s)
Radiobiology/methods , Radiobiology/standards , Radiobiology/trends , Central Nervous System/pathology , Central Nervous System , Radiation Tolerance , Apoptosis , Nervous System Neoplasms/radiotherapy , Nervous System Neoplasms/drug therapy , Nervous System Neoplasms , Central Nervous System Neoplasms/drug therapy , Central Nervous System Neoplasms/radiotherapy , Combined Modality Therapy/methods , Combined Modality Therapy/standards , Combined Modality Therapy , Combined Modality Therapy/trends , Angiogenesis Inducing Agents/administration & dosage , Angiogenesis Inducing Agents/therapeutic useABSTRACT
Existen diferentes metodologías para el estudio de la angiogénesis tumoral, destacando el cálculo de la densidad de microvasos (MVD), técnicas inmunohistoquímicas o moleculares de expresión del factor de crecimiento del endotelio vascular (VEGF) en células tumorales y medición de valores de VEGF en líquidos tumorales, séricos y ascitis. Aparecen diferencias significativas de MVD, inmunoexpresión VEGF y expresión ARNm-VEGF entre tumores epiteliales ováricos benignos y malignos. En los carcinomas ováricos, se encuentran elevados valores séricos y en ascitis (pg/ ml) de VEGF, así como de otros factores angiogénicos, respecto a los controles. Los valores de MVD, expresión VEGF o concentraciones séricas de VEGF no se correlacionan con los estadios (FIGO) y subtipos histológicos de tumores epiteliales ováricos malignos, interesante circunstancia clínica, al ser el estadio de la enfermedad un clásico factor pronóstico. No existe relación significativa entre MVD y grados histológicos, sin embargo, los tumores G3 presentan mayores porcentajes de expresión VEGF y valores séricos de VEGF, comparados con tumores G1-G2.La mayoría de las publicaciones analizadas realizan variables dicotomizaciones de la MVD que dificultan la comparación de resultados, aunque los tumores ováricos con alta densidad de microvasos aportan peores tasas de supervivencias globales. Si aparece fuerte expresión inmunohistológica VEGF tumoral o aumento de niveles séricos de VEGF, se muestran como variables significativas en la mayoría de los análisis de multivariables, tanto para tasas de supervivencias globales como para supervivencias libres de enfermedad en mujeres portadoras de tumores epiteliales ováricos malignos. La incipiente terapia antiangiogénica se dirige, en tumores ováricos con alta actividad angiogénica, hacia pequeños focos de células en emigración y proliferación capilar para que éstas sean más vulnerables a la acción de las terapéuticas adyuvantes, pero hasta la fecha, es incierta su eficacia clínica (AU)