RESUMO
Cell therapy of the post-infarcted myocardium is still far from clinical use. Poor survival of transplanted cells, insufficient regeneration, and replacement of the damaged tissue limit the potential of currently available cell-based techniques. In this study, we generated a multilayered construct from adipose-derived mesenchymal stromal cells (MSCs) modified to secrete stem cell factor, SCF. In a rat model of myocardium infarction, we show that transplantation of SCF producing cell sheet induced activation of the epicardium and promoted the accumulation of c-kit positive cells in ischemic muscle. Morphometry showed the reduction of infarct size (16%) and a left ventricle expansion index (0.12) in the treatment group compared to controls (24-28%; 0.17-0.32). The ratio of viable myocardium was more than 1.5-fold higher, reaching 49% compared to the control (28%) or unmodified cell sheet group (30%). Finally, by day 30 after myocardium infarction, SCF-producing cell sheet transplantation increased left ventricle ejection fraction from 37% in the control sham-operated group to 53%. Our results suggest that, combining the genetic modification of MSCs and their assembly into a multilayered construct, we can provide prolonged pleiotropic effects to the damaged heart, induce endogenous regenerative processes, and improve cardiac function.
Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/terapia , Pericárdio/metabolismo , Fator de Células-Tronco/metabolismo , Tecido Adiposo/citologia , Animais , Células Cultivadas , Células HEK293 , Humanos , Masculino , Pericárdio/fisiologia , Ratos , Ratos Wistar , Regeneração , Fator de Células-Tronco/genéticaRESUMO
Cell therapy remains a promising approach for the treatment of cardiovascular diseases. In this regard, the contemporary trend is the development of methods to overcome low cell viability and enhance their regenerative potential. In the present study, we evaluated the therapeutic potential of gene-modified adipose-derived stromal cells (ADSC) that overexpress hepatocyte growth factor (HGF) in a mice hind limb ischemia model. Angiogenic and neuroprotective effects were assessed following ADSC transplantation in suspension or in the form of cell sheet. We found superior blood flow restoration, tissue vascularization and innervation, and fibrosis reduction after transplantation of HGF-producing ADSC sheet compared to other groups. We suggest that the observed effects are determined by pleiotropic effects of HGF, along with the multifactorial paracrine action of ADSC which remain viable and functionally active within the engineered cell construct. Thus, we demonstrated the high therapeutic potential of the utilized approach for skeletal muscle recovery after ischemic damage associated with complex tissue degenerative effects.
Assuntos
Tecido Adiposo/citologia , Fator de Crescimento de Hepatócito/biossíntese , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Células Estromais/metabolismo , Células Estromais/transplante , Animais , Técnicas de Cultura de Células , Diferenciação Celular/genética , Movimento Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Expressão Gênica , Fator de Crescimento de Hepatócito/genética , Humanos , Isquemia , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/genética , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Crescimento Neuronal/efeitos dos fármacosRESUMO
Urokinase-type plasminogen activator (uPA) regulates angiogenesis and vascular permeability through proteolytic degradation of extracellular matrix and intracellular signaling initiated upon its binding to uPAR/CD87 and other cell surface receptors. Here, we describe an additional mechanism by which uPA regulates angiogenesis. Ex vivo VEGF-induced vascular sprouting from Matrigel-embedded aortic rings isolated from uPA knock-out (uPA(-/-)) mice was impaired compared with vessels emanating from wild-type mice. Endothelial cells isolated from uPA(-/-) mice show less proliferation and migration in response to VEGF than their wild type counterparts or uPA(-/-) endothelial cells in which expression of wild type uPA had been restored. We reported previously that uPA is transported from cell surface receptors to nuclei through a mechanism that requires its kringle domain. Intranuclear uPA modulates gene transcription by binding to a subset of transcription factors. Here we report that wild type single-chain uPA, but not uPA variants incapable of nuclear transport, increases the expression of cell surface VEGF receptor 1 (VEGFR1) and VEGF receptor 2 (VEGFR2) by translocating to the nuclei of ECs. Intranuclear single-chain uPA binds directly to and interferes with the function of the transcription factor hematopoietically expressed homeodomain protein or proline-rich homeodomain protein (HHEX/PRH), which thereby lose their physiologic capacity to repress the activity of vehgr1 and vegfr2 gene promoters. These studies identify uPA-dependent de-repression of vegfr1 and vegfr2 gene transcription through binding to HHEX/PRH as a novel mechanism by which uPA mediates the pro-angiogenic effects of VEGF and identifies a potential new target for control of pathologic angiogenesis.
Assuntos
Proteínas de Homeodomínio/metabolismo , Neovascularização Fisiológica , Fatores de Transcrição/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Movimento Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células HEK293 , Humanos , Células K562 , Camundongos Knockout , Neovascularização Fisiológica/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genéticaRESUMO
Tissue regeneration requires coordinated "teamwork" of growth factors, proteases, progenitor and immune cells producing inflammatory cytokines. Mesenchymal stem cells (MSC) might play a pivotal role by substituting cells or by secretion of growth factors or cytokines, and attraction of progenitor and inflammatory cells, which participate in initial stages of tissue repair. Due to obvious impact of inflammation on regeneration it seems promising to explore whether inflammatory factors could influence proangiogenic abilities of MSC. In this study we investigated effects of TNF-α on activity of adipose-derived stem cells (ADSC). We found that treatment with TNF-α enhances ADSC proliferation, F-actin microfilament assembly, increases cell motility and migration through extracellular matrix. Exposure of ADSC to TNF-α led to increased mRNA expression of proangiogenic factors (FGF-2, VEGF, IL-8, and MCP-1), inflammatory cytokines (IL-1ß, IL-6), proteases (MMPs, uPA) and adhesion molecule ICAM-1. At the protein level, VEGF, IL-8, MCP-1, and ICAM-1 production was also up-regulated. Pre-incubation of ADSC with TNF-α-enhanced adhesion of monocytes to ADSC but suppressed adherence of ADSC to endothelial cells (HUVEC). Stimulation with TNF-α triggers ROS generation and activates a number of key intracellular signaling mediators known to positively regulate angiogenesis (Akt, small GTPase Rac1, ERK1/2, and p38 MAP-kinases). Pre-treatment with TNF-α-enhanced ADSC ability to promote growth of microvessels in a fibrin gel assay and accelerate blood flow recovery, which was accompanied by increased arteriole density and reduction of necrosis in mouse hind limb ischemia model. These findings indicate that TNF-α plays a role in activation of ADSC angiogenic and regenerative potential.
Assuntos
Tecido Adiposo/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Actinas/metabolismo , Tecido Adiposo/metabolismo , Adulto , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citometria de Fluxo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Células-Tronco/efeitos dos fármacos , Adulto JovemRESUMO
Ex vivo, gene therapy is a powerful approach holding great promises for the treatment of both genetic and acquired diseases. Adeno-associated virus (AAV) vectors are a safe and efficient delivery system for modification of mesenchymal stem cells (MSC) that could maximize their therapeutic benefits. Assessment of MSC viability and functional activity after infection with new AAV serotypes is necessary, due to AAV tropism to specific cell types. We infected human and rat adipose-tissue MSC with hybrid AAV-DJ serotype vectors carrying GFP and SCF genes. GFP expression from AAV-DJ was about 1.5-fold superior to that observed with AAV-2 and lasted for at least 21â days as was evaluated by flow cytometry and fluorescence microscopy. AAV-DJ proves to be suitable for the infection of rat and human MSC with a similar efficiency. Infected MSC were still viable but showed a 25-30% growth-rate slowdown. Moreover, we found an increase of SERPINB2 mRNA expression in human MSC while expression of other oxidative stress markers and extracellular matrix proteins was not affected. These results suggest that there is a differential cellular response in MSC infected with AAV viral vectors, which should be taken into account as it can affect the expected outcome for the therapeutic application.
Assuntos
Dependovirus/genética , Terapia Genética , Vetores Genéticos/sangue , Células-Tronco Mesenquimais/virologia , Proteínas Virais/sangue , Animais , Proteínas de Fluorescência Verde/metabolismo , Humanos , Ratos , Sorogrupo , Fator de Células-Tronco/metabolismo , Tropismo Viral/genéticaRESUMO
Cell sheets (CS) from c-kit+ cardiac stem cell (CSC) hold a potential for application in regenerative medicine. However, manufacture of CS may require thermoresponsive dishes, which increases cost and puts one in dependence on specific materials. Alternative approaches were established recently and we conducted a short study to compare approaches for detachment of CS from c-kit+ CSC. Our in-house developed method using chelation by Versene solution was compared to UpCell™ thermoresponsive plates in terms of CSC proliferation, viability, gap junction formation and engraftment in a model of myocardial infarction. Use of Versene solution instead of thermoresponsive dishes resulted in comparable CS thickness (approximately 100mcm), cell proliferation rate and no signs of apoptosis detected in both types of constructs. However, we observed a minor reduction of gap junction count in Versene-treated CS. At day 30 after delivery to infarcted myocardium both types of CS retained at the site of transplantation and contained comparable amounts of proliferating cells indicating engraftment. Thus, we may conclude that detachment of CS from c-kit+ CSC using Versene solution followed by mechanical treatment is an alternative to thermoresponsive plates allowing use of routinely available materials to generate constructs for cardiac repair.