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1.
Braz J Med Biol Res ; 46(5): 405-16, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23797495

RESUMEN

Epigenetic mechanisms such as DNA methylation and histone modification are important in stem cell differentiation. Methylation is principally associated with transcriptional repression, and histone acetylation is correlated with an active chromatin state. We determined the effects of these epigenetic mechanisms on adipocyte differentiation in mesenchymal stem cells (MSCs) derived from bone marrow (BM-MSCs) and adipose tissue (ADSCs) using the chromatin-modifying agents trichostatin A (TSA), a histone deacetylase inhibitor, and 5-aza-2'-deoxycytidine (5azadC), a demethylating agent. Subconfluent MSC cultures were treated with 5, 50, or 500 nM TSA or with 1, 10, or 100 µM 5azadC for 2 days before the initiation of adipogenesis. The differentiation was quantified and expression of the adipocyte genes PPARG and FABP4 and of the anti-adipocyte gene GATA2 was evaluated. TSA decreased adipogenesis, except in BM-MSCs treated with 5 nM TSA. Only treatment with 500 nM TSA decreased cell proliferation. 5azadC treatment decreased proliferation and adipocyte differentiation in all conditions evaluated, resulting in the downregulation of PPARG and FABP4 and the upregulation of GATA2. The response to treatment was stronger in ADSCs than in BM-MSCs, suggesting that epigenetic memories may differ between cells of different origins. As epigenetic signatures affect differentiation, it should be possible to direct the use of MSCs in cell therapies to improve process efficiency by considering the various sources available.


Asunto(s)
Adipocitos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Desoxicitidina/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Ácidos Hidroxámicos/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , Adipocitos/citología , Adulto , Western Blotting , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Metilación de ADN , Epigenómica , Técnica del Anticuerpo Fluorescente , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Regulación hacia Arriba
2.
Braz. j. med. biol. res ; 46(5): 405-416, maio 2013. graf
Artículo en Inglés | LILACS | ID: lil-675676

RESUMEN

Epigenetic mechanisms such as DNA methylation and histone modification are important in stem cell differentiation. Methylation is principally associated with transcriptional repression, and histone acetylation is correlated with an active chromatin state. We determined the effects of these epigenetic mechanisms on adipocyte differentiation in mesenchymal stem cells (MSCs) derived from bone marrow (BM-MSCs) and adipose tissue (ADSCs) using the chromatin-modifying agents trichostatin A (TSA), a histone deacetylase inhibitor, and 5-aza-2′-deoxycytidine (5azadC), a demethylating agent. Subconfluent MSC cultures were treated with 5, 50, or 500 nM TSA or with 1, 10, or 100 µM 5azadC for 2 days before the initiation of adipogenesis. The differentiation was quantified and expression of the adipocyte genes PPARG and FABP4 and of the anti-adipocyte gene GATA2 was evaluated. TSA decreased adipogenesis, except in BM-MSCs treated with 5 nM TSA. Only treatment with 500 nM TSA decreased cell proliferation. 5azadC treatment decreased proliferation and adipocyte differentiation in all conditions evaluated, resulting in the downregulation of PPARG and FABP4 and the upregulation of GATA2. The response to treatment was stronger in ADSCs than in BM-MSCs, suggesting that epigenetic memories may differ between cells of different origins. As epigenetic signatures affect differentiation, it should be possible to direct the use of MSCs in cell therapies to improve process efficiency by considering the various sources available.


Asunto(s)
Adulto , Humanos , Persona de Mediana Edad , Adipocitos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Desoxicitidina/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Ácidos Hidroxámicos/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , Adipocitos/citología , Western Blotting , Células Cultivadas , Proliferación Celular/efectos de los fármacos , Metilación de ADN , Epigenómica , Técnica del Anticuerpo Fluorescente , Reacción en Cadena de la Polimerasa/métodos , Regulación hacia Arriba
3.
Exp Biol Med (Maywood) ; 233(7): 901-13, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18445775

RESUMEN

Mesenchymal stem cells (MSCs) have been investigated as promising candidates for use in new cell-based therapeutic strategies such as mesenchyme-derived tissue repair. MSCs are easily isolated from adult tissues and are not ethically restricted. MSC-related literature, however, is conflicting in relation to MSC differentiation potential and molecular markers. Here we compared MSCs isolated from bone marrow (BM), umbilical cord blood (UCB), and adipose tissue (AT). The isolation efficiency for both BM and AT was 100%, but that from UCB was only 30%. MSCs from these tissues are morphologically and immunophenotypically similar although their differentiation diverges. Differentiation to osteoblasts and chondroblasts was similar among MSCs from all sources, as analyzed by cytochemistry. Adipogenic differentiation showed that UCB-derived MSCs produced few and small lipid vacuoles in contrast to those of BM-derived MSCs and AT-derived stem cells (ADSCs) (arbitrary differentiation values of 245.57 +/- 943 and 243.89 +/- 145.52 mum(2) per nucleus, respectively). The mean area occupied by individual lipid droplets was 7.37 mum(2) for BM-derived MSCs and 2.36 mum(2) for ADSCs, a finding indicating more mature adipocytes in BM-derived MSCs than in treated cultures of ADSCs. We analyzed FAPB4, ALP, and type II collagen gene expression by quantitative polymerase chain reaction to confirm adipogenic, osteogenic, and chondrogenic differentiation, respectively. Results showed that all three sources presented a similar capacity for chondrogenic and osteogenic differentiation and they differed in their adipogenic potential. Therefore, it may be crucial to predetermine the most appropriate MSC source for future clinical applications.


Asunto(s)
Tejido Adiposo/citología , Células de la Médula Ósea/citología , Diferenciación Celular/fisiología , Sangre Fetal/citología , Células Madre Mesenquimatosas/citología , Adipocitos/citología , Adipocitos/metabolismo , Adulto , Anciano , Fosfatasa Alcalina/metabolismo , Antígenos de Superficie/metabolismo , Células de la Médula Ósea/metabolismo , Células Cultivadas , Condrocitos/citología , Condrocitos/metabolismo , Colágeno Tipo II/metabolismo , Femenino , Humanos , Células Madre Mesenquimatosas/metabolismo , Persona de Mediana Edad , Osteoblastos/citología , Osteoblastos/metabolismo , Embarazo
4.
Transplant Proc ; 38(5): 1596-602, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16797364

RESUMEN

UNLABELLED: In myocardial infarction and Chagas's disease, some physiopathological aspects are common: cardiomyocyte loss due to ischemia leads to a reduction of contractility and heart function. Different cells have been proposed for cellular cardiomioplasty. OBJECTIVE: Our goal was to evaluate the method of co-culture of skeletal muscle (SM) and mesenchymal stem cells (MSC) for cell therapy of heart failure in Chagas's disease (CD) and myocardium postinfarction (MI). METHODS: For MI, 39 rats completed the study at 1 month. Seventeen rats received cell therapy into the scar and 22 rats only medium. For CD, 15 rats completed the study at 1 month including 7 that received cell therapy and eight followed the natural evolution. All animals underwent ecocardiographic analysis at baseline and 1 month. Left ventricular, ejection fraction, end systolic, and end dyastolic volume were registered and analyzed by ANOVA. The co-culture method of SM and MSC was performed at 14 days (DMEM, with 15% FCS, 1% antibiotic, IGF-I, dexamethasone). Standard stain analysis was performed. RESULTS: For MI ejection fraction in the animals that received the co-cultured cells increased from 23.52+/-8.67 to 31.45+/-8.87 (P=.006) versus the results in the control group: 26.68+/-6.92 to 22.32+/-6.94 (P=.004). For CD, ejection fraction in animals that received the co-cultured cells increased from 31.10+/-5.78 to 53.37+/-5.84 (P<.001) versus the control group values of 36.21+/-3.70 to 38.19+/-7.03 (P=0.426). Histopathological analysis of the animals receiving co-cultured cells demonstrated the presence of myogenesis and angiogenesis. CONCLUSION: The results validated the product of SM and MSC co-cultures for treatment of diseases.


Asunto(s)
Trasplante de Células/fisiología , Enfermedad de Chagas/terapia , Cardiopatías/terapia , Músculo Esquelético/citología , Mioblastos/citología , Células Madre/citología , Animales , Enfermedad de Chagas/fisiopatología , Técnicas de Cocultivo , Diástole , Modelos Animales de Enfermedad , Cardiopatías/fisiopatología , Ratas , Ratas Wistar , Regeneración , Reproducibilidad de los Resultados , Sístole , Función Ventricular Izquierda
5.
Transplant Proc ; 36(4): 991-2, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15194344

RESUMEN

Currently two lines of research have been proposed for treatment of heart failure in an attempt to address its main cause: skeletal myoblast (SM) transplants, which increase the contractile muscular mass, and mesenchymal stem cell (MSC) transplants, which increase neoangiogenesis. The objective of this study was to establish methods whereby cocultures of SM and MSC proliferate and expand, making possible the interaction of these cell types prior to their transplantation to the myocardium. Seeking to support the survival of these cells after myocardial transplantation and achieve subsequent functional improvement, SM and MSC from 10 rats were isolated and cultivated in DMEM medium supplemented with 15% fetal calf serum, 1% ATB, and growth factors. Following plating in variable proportions of satellite cells/mononuclear cells namely 2:1, 1:1, 1:2, morphological observations were made regarding cell survival, adhesion to substrate, and confluence. After 48 hours nonadherent cells were aspirated from the flasks, leaving the adherent cells, SM, and MSC. The better level of cell proliferation was observed with the proportion 2:1 cocultivated at a concentration of 5 x 10(5)/mL for 14 days. The results were satisfactory; the cell production was up to 10(8), increasing the chances of transplant success after myocardial infarction. Transplants with this model are ongoing.


Asunto(s)
Mesodermo/citología , Músculo Esquelético/citología , Mioblastos/citología , Trasplante de Células Madre , Células Madre/citología , Animales , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Trasplante de Corazón , Complicaciones Posoperatorias/terapia , Ratas
6.
Transplant Proc ; 36(4): 1023-4, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15194356

RESUMEN

Due to the peculiar characteristics of skeletal muscle, myoblast transplants have emerged as a therapy for cardiomyopathy, particularly after myocardial infarction. The objectives of this study were to define the mean time of cultivation necessary to obtain a cellular concentration of 10(6) to expand the mass for transplant, and to identify the proliferation phase of myoblasts. Ten myoblast cultures were performed using newborn Wistar rats. The isolation method used enzymatic dissociation in culture medium (HAM-F12 and 199) supplement with basic-fibroblast growth factor (b-FGF) and insulin growth factor (IGF-I). The mean cultivation time to obtain the desired concentration of 10(6) was 7 days, with expansion of up to 10(8)/g. When b-FGF was used, the cellular yield was approximately 10(7), with IGF-I the cellular yield was approximately 10(8), independent of the medium. We concluded that IGF-I is the better option for mass cellular expansion of myoblasts for application in myocardial transplants.


Asunto(s)
Trasplante de Corazón , Mioblastos/citología , Mioblastos/trasplante , Animales , Técnicas de Cultivo de Célula/métodos , Medios de Cultivo , Sustancias de Crecimiento/farmacología , Modelos Animales , Mioblastos/efectos de los fármacos , Ratas
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