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1.
Stem Cells Dev ; 30(2): 79-90, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33256572

RESUMO

Forced coexpression of the transcription factors Oct3/4, Klf4, Sox2, and c-Myc reprograms somatic cells into pluripotent stem cells (PSCs). Such induced PSCs (iPSCs) can generate any cell type of the adult body or indefinitely proliferate without losing their potential. Accordingly, iPSCs can serve as an unlimited cell source for the development of various disease models and regenerative therapies for animals and humans. Although canine peripheral blood mononuclear cells (PBMCs) can be easily obtained, they have a very low iPSC reprogramming efficiency. In this study, we determined the reprogramming efficiency of canine PBMCs under several conditions involving three types of media supplemented with small-molecule compounds. We found that canine iPSCs (ciPSCs) could be efficiently generated from PBMCs using N2B27 medium supplemented with leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF), and a small-molecule cocktail (Y-27632, PD0325901, CHIR99021, A-83-01, Forskolin, and l-ascorbic acid). We generated five ciPSC lines that could be maintained in StemFit® medium supplemented with LIF. The SeVdp(KOSM)302L vectors were appropriately silenced in four ciPSC lines. Of the two lines characterized, both were positive for alkaline phosphatase activity and expressed pluripotency markers, including the Oct3/4, Sox2, and Nanog transcripts, as well as the octamer-binding transcription factor (OCT) 3/4 and NANOG proteins, and the SSEA-1 carbohydrate antigen. The ciPSCs could form embryoid bodies and differentiate into the three germ layers, as indicated by marker gene and protein expression. Furthermore, one ciPSC line formed teratomas comprising several tissues from every germ layer. Our ciPSC lines maintained a normal karyotype even after multiple passages. Moreover, our new reprogramming method was able to generate ciPSCs from multiple donor PBMCs. In conclusion, we developed an easy and efficient strategy for the generation of footprint-free ciPSCs from PBMCs. We believe that this strategy can be useful for disease modeling and regenerative medicine in the veterinary field.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Expressão Gênica/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares/metabolismo , Animais , Células Cultivadas , Técnicas de Reprogramação Celular/métodos , Meios de Cultura/química , Meios de Cultura/farmacologia , Cães , Ectoderma/citologia , Ectoderma/metabolismo , Endoderma/citologia , Endoderma/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Leucócitos Mononucleares/citologia , Mesoderma/citologia , Mesoderma/metabolismo , Camundongos Endogâmicos ICR , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Reprodutibilidade dos Testes , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
2.
In Vitro Cell Dev Biol Anim ; 54(8): 567-579, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30030768

RESUMO

P19 embryonal carcinoma cells (EC-cells) provide a simple and robust culture system for studying neural development. Most protocols developed so far for directing neural differentiation of P19 cells depend on the use of culture medium supplemented with retinoic acid (RA) and serum, which has an undefined composition. Hence, such protocols are not suitable for many molecular studies. In this study, we achieved neural differentiation of P19 cells in a serum- and RA-free culture medium by employing the knockout serum replacement (KSR) supplement. In the KSR-containing medium, P19 cells underwent predominant differentiation into neural lineage and by day 12 of culture, neural cells were present in 100% of P19-derived embryoid bodies (EBs). This was consistently accompanied by the increased expression of various neural lineage-associated markers during the course of differentiation. P19-derived neural cells comprised of NES+ neural progenitors (~ 46%), TUBB3+ immature neurons (~ 6%), MAP2+ mature neurons (~ 2%), and GFAP+ astrocytes (~ 50%). A heterogeneous neuronal population consisting of glutamatergic, GABAergic, serotonergic, and dopaminergic neurons was generated. Taken together, our study shows that the KSR medium is suitable for the differentiation of P19 cells to neural lineage without requiring additional (serum and RA) supplements. This stem cell differentiation system could be utilized for gaining mechanistic insights into neural differentiation and for identifying potential neuroactive compounds.


Assuntos
Diferenciação Celular , Células-Tronco de Carcinoma Embrionário/citologia , Neurônios/citologia , Tretinoína/farmacologia , Animais , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro , Endoderma/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Mesoderma/citologia , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo
3.
Stem Cell Reports ; 8(2): 305-317, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28089668

RESUMO

Subtype-specific human cardiomyocytes (CMs) are valuable for basic and applied research. Induction of cardiomyogenesis and enrichment of nodal-like CMs was described for mouse pluripotent stem cells (mPSCs) in response to 1-ethyl-2-benzimidazolinone (EBIO), a chemical modulator of small-/intermediate-conductance Ca2+-activated potassium channels (SKs 1-4). Investigating EBIO in human pluripotent stem cells (PSCs), we have applied three independent differentiation protocols of low to high cardiomyogenic efficiency. Equivalent to mPSCs, timed EBIO supplementation during hPSC differentiation resulted in dose-dependent enrichment of up to 80% CMs, including an increase in nodal- and atrial-like phenotypes. However, our study revealed extensive EBIO-triggered cell loss favoring cardiac progenitor preservation and, subsequently, CMs with shortened action potentials. Proliferative cells were generally more sensitive to EBIO, presumably via an SK-independent mechanism. Together, EBIO did not promote cardiogenic differentiation of PSCs, opposing previous findings, but triggered lineage-selective survival at a cardiac progenitor stage, which we propose as a pharmacological strategy to modulate CM subtype composition.


Assuntos
Benzimidazóis/farmacologia , Agonistas dos Canais de Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Biomarcadores , Diferenciação Celular/genética , Linhagem Celular , Linhagem da Célula , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Mesoderma/citologia , Mesoderma/efeitos dos fármacos , Mesoderma/embriologia , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes/metabolismo
4.
Planta Med ; 83(9): 761-769, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28010025

RESUMO

Evodiamine, a major component of Evodia rutaecarpa, can protect the myocardium against injury induced by atherosclerosis and ischemia-reperfusion. However, the effect of evodiamine against cardiac fibrosis remains unclear. This study aims to investigate the possible effect and mechanism involved in the function of evodiamine on isoproterenol-induced cardiac fibrosis and endothelial-to-mesenchymal transition. Isoproterenol was used to induce cardiac fibrosis in mice, and evodiamine was gavaged simultaneously. After 14 days, cardiac function was accessed by echocardiography. The extent of cardiac fibrosis and hypertrophy was evaluated by pathological and molecular analyses. The extent of endothelial-to-mesenchymal transition was evaluated by the expression levels of CD31, CD34, α-smooth muscle actin, and vimentin by immunofluorescence staining and Western blot analysis. After 14 days, the heart weight/body weight ratio and heart weight/tibia length ratio revealed no significant difference between the isoproterenol group and the isoproterenol/evodiamine-treated groups, whereas the increased heart weight was reduced in the isoproterenol/evodiamine-treated groups. Echocardiography revealed that interventricular septal thickness and left ventricular posterior wall thickness at the end diastole decreased in the evodiamine-treated groups. Evodiamine reduced isoproterenol-induced cardiac fibrosis as accessed by normalization in collagen deposition and gene expression of hypertrophic and fibrotic markers. Evodiamine also prevented endothelial-to-mesenchymal transition as evidenced by the increased expression levels of CD31 and CD34, decreased expression levels of α-smooth muscle actin and vimentin, and increased microvascular density in the isoproterenol/evodiamine-treated mice hearts. Furthermore, isoproterenol-induced activation of transforming growth factor-ß1/Smad signal was also blunted by evodiamine. Therefore, evodiamine may prevent isoproterenol-induced cardiac fibrosis by regulating endothelial-to-mesenchymal transition, which is probably mediated by the blockage of the transforming growth factor-ß1/Smad pathway.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Fibrose/prevenção & controle , Mesoderma/citologia , Miocárdio/patologia , Extratos Vegetais/uso terapêutico , Quinazolinas/uso terapêutico , Animais , Ecocardiografia , Endotélio Vascular/citologia , Evodia , Fibrose/induzido quimicamente , Coração/efeitos dos fármacos , Isoproterenol , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Transformador beta1/biossíntese
5.
Dev Growth Differ ; 53(6): 780-92, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21711459

RESUMO

Bone morphogenetic proteins (BMPs) play a crucial role in programmed cell death (PCD), a biological process required for the sculpturing of the embryonic limbs. However, it is unknown if BMP signaling directly promotes cell death, or if it induces a molecular cascade that culminates in cell death. Given that Smad8, which encodes one component of BMP signaling, is expressed during the regression of interdigital tissue and responds to BMPs, we presumed that it may be expressed in other cell death areas during chick limb development such as the anterior and posterior necrotic zones (ANZ and PNZ). The present study found that the Smad8 expression pattern in the anterior mesoderm of the hindlimb is very similar to that observed in limbs stained to detect cell death. Also, BMPs and retinoic acid, which act as apoptosis-promoting factors, induced expression of Smad8 before the onset of cell death, while sonic hedgehog protein, acting as a survival factor, inhibited Smad8 expression in the ANZ. However, although there was correlation between Smad8 expression patterns and PCD in the ANZ, phosphorylated forms of SMAD1/5/8 and TUNEL staining did not co-localize in dying cells. Interestingly, a short pulse of BMP was sufficient to trigger cell death. On the other hand, most dying cells were located in the avascular region, while many cells expressing Smad8 were located in the vascular region of the ANZ. These results suggest that BMPs mediated by SMAD signaling activate a molecular cascade that culminates in PCD.


Assuntos
Proteína Morfogenética Óssea 7/farmacologia , Morte Celular , Embrião de Galinha/efeitos dos fármacos , Membro Posterior/embriologia , Proteína Smad8/metabolismo , Animais , Embrião de Galinha/citologia , Embrião de Galinha/embriologia , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Desenvolvimento Embrionário , Imunofluorescência , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Proteínas Hedgehog/farmacologia , Membro Posterior/citologia , Membro Posterior/efeitos dos fármacos , Humanos , Mesoderma/citologia , Mesoderma/efeitos dos fármacos , Mesoderma/metabolismo , Microscopia Confocal , Fosforilação , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Proteína Smad8/genética , Fatores de Tempo , Tretinoína/administração & dosagem , Tretinoína/farmacologia
6.
Arch Pharm Res ; 34(3): 477-83, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21547681

RESUMO

Salvianolic acid B (Sal B) is the most abundant bioactive molecule from Radix Salviae Miltiorrhizae, and has recently been used for treating renal fibrosis in traditional Chinese medicine. Here we investigated the ability reversal of Sal B to reverse the transdifferentiation of human kidney proximal tubular epithelial cells that was induced by transforming growth factor-beta 1 (TGF-ß1). The effects of Sal B on HK-2 cell morphology were observed by phase contrast microscopy, while alpha smooth muscle actin and E-cadherin were studied by immunocytochemistry and real-time reverse transcription polymerase chain reaction, respectively. Exposure of HK-2 cells to TGF-ß1 for 72 h induced a complete conversion of the epithelial cells to myofibroblasts. When HK-2 cells were co-incubated with Sal B and TGF-ß1 for a further 72 h, the morphology of myofibroblasts returned to that of proximal tubular epithelial cells, whereas the myofibroblast phenotype was maintained after exposure of cells to TGF-ß1 for 144 h. Sal B reduced alpha smooth muscle actin levels and increased E-cadherin levels compared with their epithelial-to-mesenchymal transition controls. The reversal effect of Sal B was dose-dependent. That Sal B reverses the epithelial-to-mesenchymal transition in vitro suggests that it could possibly facilitate the repair of tubular epithelial structures and the regression of renal fibrosis in injured kidneys.


Assuntos
Benzofuranos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Mesoderma/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Células Epiteliais/citologia , Fibrose/patologia , Fibrose/prevenção & controle , Humanos , Rim/citologia , Rim/efeitos dos fármacos , Rim/patologia , Mesoderma/citologia , Microscopia de Contraste de Fase
7.
J Endod ; 36(7): 1139-44, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20630286

RESUMO

INTRODUCTION: Stem cell lines are usually grown in medium containing animal products. Fetal bovine serum (FBS) is an important additive for cell growth; however, the allergenic potential and the possibility of contamination when we use a medium containing serum would be a barrier to transplantation and consequently to the introduction of cell therapy methods into clinical applications. METHODS: Dental mesenchymal cells were isolated and expanded in vitro and maintained in 4 different serum-free media (SFMs): SFM#1 (ITS-X, embryotrophic factor [ETF]); SFM#2 (ITS-X); SFM#3 (ETF); and SFM#4 (ETF, sodium pyruvate, ascorbic acid, fibroblast growth factor [FGF-a], acidic). Viability, proliferative, and immunocytochemical tests for the cells were performed by using 4 stem cell markers (CD44H, CK19, nestin, and P63) for ectoderm, mesoderm, and endoderm. RESULTS: Viability tests showed a significant difference between the control and SFMs in both deciduous tooth pulp cells (DTPCs) and wisdom tooth pulp cells (WTPCs). However, all SFMs demonstrated 84%-90% viability, whereas the control showed 90%-93%. In both DTPCs and WTPCs, SFM#1 had the highest proliferation rate among the 4 SFMs. Immunocytochemistry stained positive stem cell markers most intensely in cells cultured with SFM#1. Furthermore, all stem cell markers for ectoderm, mesoderm, and endoderm were expressed in the cells cultured with SFM#1. CONCLUSIONS: SFM#1 showed an acceptable survival rate, the highest proliferation rate, and the strongest expression of all the stem cell markers. SFM#1 proved to be a suitable medium for the culture of human dental pulp stem cells and to preserve pluripotency in differentiation.


Assuntos
Técnicas de Cultura de Células , Meios de Cultura Livres de Soro , Polpa Dentária/citologia , Células-Tronco Mesenquimais/fisiologia , Animais , Ácido Ascórbico/farmacologia , Biomarcadores/análise , Bovinos , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura , Polpa Dentária/efeitos dos fármacos , Ectoderma/citologia , Endoderma/citologia , Fator 1 de Crescimento de Fibroblastos/farmacologia , Humanos , Receptores de Hialuronatos/análise , Insulina/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Proteínas de Filamentos Intermediários/análise , Queratina-19/análise , Células-Tronco Mesenquimais/efeitos dos fármacos , Mesoderma/citologia , Dente Serotino/citologia , Proteínas do Tecido Nervoso/análise , Nestina , Ácido Pirúvico/farmacologia , Selênio/farmacologia , Dente Decíduo/citologia , Transativadores/análise , Fatores de Transcrição , Transferrina/farmacologia , Proteínas Supressoras de Tumor/análise
8.
Proc Natl Acad Sci U S A ; 107(29): 12907-12, 2010 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-20615943

RESUMO

Vertebrate embryo somite formation is temporally controlled by the cyclic expression of somitogenesis clock genes in the presomitic mesoderm (PSM). The somitogenesis clock is believed to be an intrinsic property of this tissue, operating independently of embryonic midline structures and the signaling molecules produced therein, namely Sonic hedgehog (Shh). This work revisits the notochord signaling contribution to temporal control of PSM segmentation by assessing the rate and number of somites formed and somitogenesis molecular clock gene expression oscillations upon notochord ablation. The absence of the notochord causes a delay in somite formation, accompanied by an increase in the period of molecular clock oscillations. Shh is the notochord-derived signal responsible for this effect, as these alterations are recapitulated by Shh signaling inhibitors and rescued by an external Shh supply. We have characterized chick smoothened expression pattern and have found that the PSM expresses both patched1 and smoothened Shh signal transducers. Upon notochord ablation, patched1, gli1, and fgf8 are down-regulated, whereas gli2 and gli3 are overexpressed. Strikingly, notochord-deprived PSM segmentation rate recovers over time, concomitant with raldh2 overexpression. Accordingly, exogenous RA supplement rescues notochord ablation effects on somite formation. A model is presented in which Shh and RA pathways converge to inhibit PSM Gli activity, ensuring timely somite formation. Altogether, our data provide evidence that a balance between different pathways ensures the robustness of timely somite formation and that notochord-derived Shh is a component of the molecular network regulating the pace of the somitogenesis clock.


Assuntos
Padronização Corporal , Proteínas Hedgehog/metabolismo , Somitos/metabolismo , Animais , Relógios Biológicos/efeitos dos fármacos , Relógios Biológicos/genética , Padronização Corporal/efeitos dos fármacos , Embrião de Galinha , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Mesoderma/citologia , Mesoderma/efeitos dos fármacos , Mesoderma/metabolismo , Notocorda/citologia , Notocorda/efeitos dos fármacos , Notocorda/metabolismo , Transdução de Sinais/efeitos dos fármacos , Somitos/citologia , Somitos/efeitos dos fármacos , Fatores de Tempo , Tretinoína/farmacologia
9.
BMC Cell Biol ; 11: 31, 2010 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-20441599

RESUMO

BACKGROUND: Salvianolic Acid B (Sal B) is a water-soluble component from Danshen (a traditional Chinese herb widely used for chronic renal diseases) with anti-oxidative and cell protective properties. Sal B also has potential protective effects on renal diseases. Tubular epithelial cells can undergo epithelial-to-mesenchymal transition (EMT), which plays an important role in the pathogenesis of renal interstitial fibrosis (RIF) and is mainly regulated by TGF-beta1/Smads pathway. The aims of the study are to investigate the effect of Sal B on tubular EMT in vivo and in vitro, and to elucidate its underlying mechanism against EMT related to TGF-beta1/Smads pathway. RESULTS: For in vivo experiments, RIF was induced in rats by oral administration of HgCl2 and prophylaxised with Sal B and vitamin E. The protein expression of E-cadherin was down-regulated, while the expression of alpha-SMA, TGF-beta1, TbetaR-I, p-Smad2/3 and the activity of matrix metalloproteinase-2 (MMP-2) were up-regulated in kidneys of model rats when compared with those of normal rats. In contrast, Sal B and vitamin E significantly attenuated the expression of alpha-SMA, TGF-beta1, TbetaR-I, p-Smad2/3, and MMP-2 activity, but increased E-cadherin expression. For in vitro experiments, HK-2 cells were incubated with TGF-beta1 to induce EMT, and the cells were co-cultured with 1 and 10 microM Sal B or SB-431542 (a specific inhibitor of TbetaR-I kinase). TGF-beta1 induced a typical EMT in HK-2 cells, while it was blocked by Sal B and SB-431542, as evidenced by blocking morphologic transformation, restoring E-cadherin and CK-18 expression, inhibiting alpha-SMA expression and F-actin reorganization, and down-regulating MMP-2/9 activities in TGF-beta1 mediated HK-2 cells. Furthermore, Sal B and SB-431542 profoundly down-regulated the expressions of TbetaR-I and p-Smad2/3 but prevented the decreased expression of Smad7 in TGF-beta1 stimulated HK-2 cells. CONCLUSIONS: Sal B can prevent tubular EMT in the fibrotic kidney induced by HgCl2 as well as HK-2 cells triggered by TGF-beta1, the mechanism of Sal B is closely related to the regulation of TGF-beta1/Smads pathway, manifested as the inhibition of TGF-beta1 expression, suppression of TbetaR-I expression and function, down-regulation of Smad2/3 phosphorylation, and restoration of the down-regulation of Smad7, as well as inhibition of MMP-2 activity.


Assuntos
Benzofuranos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/citologia , Rim/patologia , Mesoderma/citologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular , Fibrose/metabolismo , Humanos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteína Smad7/metabolismo , Regulação para Cima
10.
Altern Lab Anim ; 38(2): 183-92, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20507188

RESUMO

New medicinal products and procedures must meet very strict safety criteria before being applied for use in humans. The laboratory procedures involved require the use of large numbers of animals each year. Furthermore, such investigations do not always give an accurate translation to the human setting. Here, we propose a viable alternative to animal testing, which uses novel technology featuring human cord and cord blood stem cells. With over 130 million children born each year, cord and cord blood remains the most widely available alternative to the use of animals or cadaveric human tissues for in vitro toxicology.


Assuntos
Alternativas aos Testes com Animais/normas , Órgãos Artificiais , Sangue Fetal/fisiologia , Regeneração/fisiologia , Células-Tronco/fisiologia , Cordão Umbilical/fisiologia , Animais , Ectoderma/citologia , Ectoderma/fisiologia , Endoderma/citologia , Endoderma/fisiologia , Sangue Fetal/citologia , Sangue Fetal/imunologia , Humanos , Tolerância Imunológica , Recém-Nascido , Mesoderma/citologia , Mesoderma/fisiologia , Células-Tronco/citologia , Células-Tronco/imunologia , Cordão Umbilical/citologia , Cordão Umbilical/imunologia
11.
Biochim Biophys Acta ; 1800(6): 611-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20188144

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is associated with obesity, insulin resistance and hepatic steatosis. Non-alcoholic steatohepatitis (NASH) is a serious consequence of NAFLD where chronic tissue damage and inflammation result in fibrosis which may progress to cirrhosis. Transforming growth factor beta1 (TGFbeta1), proinflammatory cytokines and oxidative stress are thought to play crucial roles in the pathogenesis of these conditions. The contributions of individual liver cell types to fibrogenesis remain controversial and the influence of selenium status has not been investigated. METHODS: In this study we have used a cell culture model of fat-loading using oleate-treated human hepatoblastoma (C3A) cells to investigate how fat-loading and selenium status might influence the production of collagen in response to TGFbeta1. The secretion of inflammatory cytokines was also investigated, together with the epithelial character of the treated cells. RESULTS: We found that in response to treatment with TGFbeta1, C3A cells produced mRNA encoding the pro-alphaI chain of procollagen I, secreted procollagen I peptide, up-regulated production of the proinflammatory cytokine interleukin-8 (IL-8) and the mesenchymal marker vimentin, and down-regulated albumin production. Most of these responses were considerably enhanced when cells were fat-loaded with oleate and were attenuated by selenium addition at a dose that optimised the expression of thioredoxin reductase and glutathione peroxidase. CONCLUSIONS: Our data establish that both fat-loading and suboptimal selenium status enhance collagen and IL-8 production by C3A hepatocytes in response to TGFbeta1, possibly as part of an epithelial to mesenchymal transition. GENERAL SIGNIFICANCE: These findings suggest that the hepatocyte may be an important contributor to the pathogenesis of fibrosis associated with NAFLD.


Assuntos
Gorduras/análise , Hepatoblastoma/metabolismo , Interleucina-8/biossíntese , Neoplasias Hepáticas/metabolismo , Pró-Colágeno/biossíntese , Selênio/administração & dosagem , Fator de Crescimento Transformador beta1/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Células Epiteliais/citologia , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/patologia , Mesoderma/citologia , Reação em Cadeia da Polimerase , Selênio/farmacologia
12.
Tissue Eng Part A ; 15(12): 3741-51, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19519274

RESUMO

In tissue engineering, strategies are being developed to repair large bone defects by combining biomaterials and bone marrow-derived multipotent mesenchymal stromal cells (MSCs). For expansion of MSCs under good manufacturing practice conditions, human platelet lysate (PL) can serve as substitute for fetal bovine serum (FBS) in culture media. We compared the in vivo bone-forming capacity of passage 3 MSCs cultured with either PL or FBS for nine different human donors. We also tested the growth kinetics, antigen expression profile, and the multilineage differentiation capacity in vitro of these MSCs. The in vivo bone-forming capacity was determined by seeding culture-expanded MSCs onto biphasic calcium phosphate scaffolds. Hybrid constructs were implanted subcutaneously in nude mice, retrieved after 6 weeks, and analyzed using histomorphometry. PL-supplemented cultures resulted in significantly larger colonies, shorter culture time period, and higher population doublings between P1 and P3 compared to FBS-containing cultures. No differences were observed in antigen expression profiles or differentiation capacities into the osteoblastic, chondrogenic, and adipogenic lineages, qualitatively. In vivo bone formation with PL-supplemented cultures of MSCs was demonstrated in 9/9 donors versus 6/9 for FBS-supplemented cultures. These results warrant the use of PL for ex vivo expansion of human MSCs for bone tissue engineering applications.


Assuntos
Plaquetas/citologia , Extratos Celulares/farmacologia , Mesoderma/citologia , Osteogênese/efeitos dos fármacos , Soro/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Animais , Antígenos/imunologia , Substitutos Sanguíneos/farmacologia , Bovinos , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Humanos , Imunofenotipagem , Cinética , Camundongos , Células Estromais/citologia
13.
Blood ; 113(19): 4525-33, 2009 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-19196659

RESUMO

The peculiar site of development of primary effusion lymphoma (PEL) highlights a specific role of body cavities in the pathogenesis of this neoplasia. We used a xenograft murine model of PEL to characterize the contribution of the host microenvironment to PEL growth. The activity of a murine (ie, host-specific) interferon-alpha(1) (IFN-alpha(1))-expressing lentiviral vector (mIFN-alpha(1)-LV) was compared with that of a human (h) IFN-alpha(2)b-LV. LVs efficiently delivered the transgene to PEL cells and conferred long-term transgene expression in vitro and in vivo. Treatment of PEL-injected severe combined immunodeficiency mice with hIFN-alpha(2)b-LV significantly prolonged mice survival and reduced ascites development. Interestingly, mIFN-alpha(1)-LV showed an antineoplastic activity comparable with that observed with hIFN-alpha(2)b-LV. As mIFN-alpha(1) retained species-restricted activity in vitro, it probably acted in vivo on the intracavitary murine milieu. mIFN-alpha(1)-treated murine mesothelial cells were found to express tumor necrosis factor-related apoptosis-inducing ligand and to significantly trigger apoptosis of cocultured PEL cells in a tumor necrosis factor-related apoptosis-inducing ligand-dependent manner. These data suggest that the interaction between lymphomatous and mesothelial cells lining the body cavities may play a key role in PEL growth control and also indicate that the specific targeting of microenvironment may impair PEL development.


Assuntos
Antineoplásicos/uso terapêutico , Vetores Genéticos , Interferon-alfa/uso terapêutico , Lentivirus/genética , Linfoma de Efusão Primária/tratamento farmacológico , Animais , Células Cultivadas , Citocinas/metabolismo , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Interferon alfa-2 , Rim/citologia , Rim/efeitos dos fármacos , Rim/metabolismo , Linfoma de Efusão Primária/genética , Linfoma de Efusão Primária/patologia , Mesoderma/citologia , Mesoderma/efeitos dos fármacos , Mesoderma/metabolismo , Camundongos , Camundongos SCID , Peritônio/citologia , Peritônio/efeitos dos fármacos , Peritônio/metabolismo , Proteínas Recombinantes
14.
Tissue Eng Part A ; 15(7): 1855-64, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19196152

RESUMO

Controlled differentiation of embryonic stem cells (ESC) is necessary to their use as a cell source for tissue engineering or regeneration. To date, most studies have concentrated on chemical cues to direct ESC differentiation. However, during normal embryonic development, multiple factors beyond chemical cues play a role, including the extracellular matrix (ECM) in bone development. In this study, we use nanofibrous (NF) matrices to mimic the morphology of the ECM to examine the contribution of the ECM morphology to the differentiation of mouse ESC. After 12 h of differentiation culture, mouse ESC form protrusions interacting with NF matrices, while they appear not to interact with flat films. Immunofluorescence staining after 26 days of differentiation culture indicates a greater degree of differentiation for mouse ESC on NF matrices compared to flat films. Polymerase chain reaction results, also, show greater degree of osteogenic differentiation on NF matrices compared to flat films when osteogenic supplements are added to the culture. Overall, these results demonstrate that NF morphology contributes to the controlled differentiation of mouse ESC.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/citologia , Nanoestruturas/química , Osteogênese , Adsorção , Animais , Biomarcadores/metabolismo , Calcificação Fisiológica , Meios de Cultura , Células-Tronco Embrionárias/metabolismo , Matriz Extracelular/metabolismo , Integrinas/antagonistas & inibidores , Integrinas/metabolismo , Mesoderma/citologia , Camundongos , Nanoestruturas/ultraestrutura
15.
Stem Cells ; 26(10): 2724-34, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18583539

RESUMO

In the present study, the potential of selenium to enhance stem cell behavior through improvement of human adipose tissue-derived stromal cells (ATSCs) and the associated molecular mechanism was evaluated. Selenium-induced improvement in stem cell behavior of human ATSCs caused expression of several genes, indicating downregulated mature cell marker proteins coupled with increased cell growth and telomerase activities after the overexpression of Rex1, Nanog, OCT4, SOX2, KLF4, and c-Myc. Also, selenium-treated ATSCs significantly downregulated p53 and p21 tumor suppressor gene products. Selenium induced active growth and growth enhanced by the activation of signal proteins in ATSCs via the inhibition of reactive oxygen species-mediated phospho-stress-activated protein kinase/c-Jun N-terminal protein kinase activation. The selenium-induced activation of extracellular regulated kinases 1/2 and Akt in ATSCs resulted in a subsequent induction of the expression of stemness transcription factors, particularly Rex1, Nanog, and Oct4, along with definitive demethylation on regulatory regions of Rex-1, Nanog, and Oct4. The results of our small interfering RNA knockdown experiment showed that Rex1 plays a major role in the proliferation of selenium-induced ATSCs. Selenium-treated ATSCs also exhibited more profound differentiation into mesodermal and neural lineages. We performed a direct comparison of gene expression profiles in control ATSCs and selenium-treated ATSCs and delineated specific members of important growth factor, signaling, cell adhesion, and transcription factor families. The observations of improved life span and multipotency of selenium-treated ATSCs clearly indicate that selenium-treated ATSCs represent an extraordinarily useful candidate cell source for tissue regeneration. Disclosure of potential conflicts of interest is found at the end of this article.


Assuntos
Tecido Adiposo/citologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Selênio/farmacologia , Células-Tronco/citologia , Células Estromais/citologia , Células Estromais/enzimologia , Tecido Adiposo/enzimologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Fator 4 Semelhante a Kruppel , Mesoderma/citologia , Mesoderma/efeitos dos fármacos , Camundongos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Regiões Promotoras Genéticas , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/enzimologia , Células Estromais/efeitos dos fármacos , Telomerase/metabolismo , Fatores de Transcrição/genética
16.
Stem Cells ; 26(6): 1464-73, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18369102

RESUMO

Pluripotent stem cells demonstrate an inherent propensity for unrestricted multi-lineage differentiation. Translation into regenerative applications requires identification and isolation of tissue-specified progenitor cells. From a comprehensive pool of 11,272 quality-filtered genes, profiling embryonic stem cells at discrete stages of cardiopoiesis revealed 736 transcripts encoding membrane-associated proteins, where 306 were specifically upregulated with cardiogenic differentiation. Bioinformatic dissection of exposed surface biomarkers prioritized the chemokine receptor cluster as the most significantly over-represented gene receptor family during pre cardiac induction, with CXCR4 uniquely associated with mesendoderm formation. CXCR4(+) progenitors were sorted from the embryonic stem cell pool into mesoderm-restricted progeny according to co-expression with the early mesoderm marker Flk-1. In contrast to CXCR4(-)/Flk-1(-) cells, the CXCR4(+)/Flk-1(+) subpopulation demonstrated overexpressed cardiac lineage transcription factors (Mef2C, Myocardin, Nkx2.5), whereas pluripotent genes (Oct4, Fgf4, Sox2) as well as neuroectoderm (Sox1) and endoderm alpha-fetoprotein markers were all depleted. In fact, the CXCR4(+)/Flk-1(+) biomarker combination identified embryonic stem cell progeny significantly enriched with Mesp-1, GATA-4, and Tbx5, indicative of pre cardiac mesoderm and the primary heart field. Although the CXCR4(+)/Flk-1(+) transcriptome shared 97% identity with the CXCR4(-)/Flk-1(-) counterpart, the 818 divergent gene set represented predominantly cardiovascular developmental functions and formed a primitive cardiac network. Differentiation of CXCR4(+)/Flk-1(+) progenitors yielded nuclear translocation of myocardial transcription factors and robust sarcomerogenesis with nascent cardiac tissue demonstrating beating activity and calcium transients. Thus, the CXCR4/Flk-1 biomarker pair predicts the emergence of cardiogenic specification within a pluripotent stem cell pool, enabling targeted selection of cardiopoietic lineage. Disclosure of potential conflicts of interest is found at the end of this article.


Assuntos
Células-Tronco Embrionárias/citologia , Miócitos Cardíacos/fisiologia , Receptores CXCR4/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Animais , Biomarcadores/análise , Cálcio/fisiologia , Diferenciação Celular , DNA Complementar/genética , Células-Tronco Embrionárias/fisiologia , Endoderma/citologia , Endoderma/fisiologia , Perfilação da Expressão Gênica , Mesoderma/citologia , Mesoderma/fisiologia , Camundongos , Miócitos Cardíacos/citologia , RNA/genética , RNA/isolamento & purificação
17.
Stem Cells Dev ; 16(1): 39-52, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17233553

RESUMO

Bone matrix production and mineralization involves sophisticated mechanisms, including the initial formation of an organic extracellular matrix into which inorganic hydroxyapatite crystals are later deposited. Human embryonic stem (hES) cells offer a potential to study early developmental processes and provide an unlimited source of cells. In this study, four different hES cell lines were used, and two different approaches to differentiate hES cells into the osteogenic lineage were taken. Undifferentiated cells were cultured either in suspension, facilitating the formation of embryoid bodies (EBs), or in monolayer, and both methods were in the presence of osteogenic supplements. Novel to our osteogenic differentiation study was the use of commercially available human foreskin fibroblasts to support the undifferentiated growth of the hES cell colonies, and their propagation in serum replacement-containing medium. Characterization of the osteogenic phenotype revealed that all hES cell lines differentiated toward the mesenchymal lineage, because T-Brachyury, Flt-1, and bone morphogenetic protein-4 could be detected. Main osteoblastic marker genes Runx2, osterix, bone sialoprotein, and osteocalcin were up-regulated. Alizarin Red S staining demonstrated the formation of bone-like nodules, and bone sialoprotein and osteocalcin were localized to these foci by immunohistochemistry. Cells differentiated in monolayer conditions exhibited greater osteogenic potential compared to those from EB-derived cells. We conclude that in vitro hES cells can produce a mineralized matrix possessing all the major bone markers, the differentiation of pluripotent hES cells to an osteogenic lineage does not require initiation via EB formation, and that lineage potential is not dependent on the mode of differentiation induction but on a cell line itself.


Assuntos
Matriz Óssea/metabolismo , Matriz Óssea/fisiologia , Técnicas de Cultura de Células/métodos , Células-Tronco Embrionárias/citologia , Osteogênese , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Fosfatos de Cálcio/metabolismo , Diferenciação Celular , Linhagem da Célula , Fibroblastos , Prepúcio do Pênis/citologia , Marcadores Genéticos , Humanos , Masculino , Mesoderma/citologia , Osteoblastos/citologia , Fenótipo , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Neurochem ; 98(2): 629-40, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16771838

RESUMO

Neurogenesis in the adult human brain occurs within two principle neurogenic regions, the hippocampus and the subventricular zone (SVZ) of the lateral ventricles. Recent reports demonstrated the isolation of human neuroprogenitor cells (NPCs) from these regions, but due to limited tissue availability the knowledge of their phenotype and differentiation behavior is restricted. Here we characterize the phenotype and differentiation capacity of human adult hippocampal NPCs (hNPCs), derived from patients who underwent epilepsy surgery, on various feeder cells including fetal mixed cortical cultures, mouse embryonic fibroblasts (MEFs) and PA6 stromal cells. Isolated hNPCs were cultured in clonal density by transferring the cells to serum-free media supplemented with FGF-2 and EGF in 3% atmospheric oxygen. These hNPCs showed neurosphere formation, expressed high levels of early neuroectodermal markers, such as the proneural genes NeuroD1 and Olig2, the NSC markers Nestin and Musashi1, the proliferation marker Ki67 and significant activity of telomerase. The phenotype was CD15low/-, CD34-, CD45- and CD133-. After removal of mitogens and plating them on poly D-lysine, they spontaneously differentiated into a neuronal (MAP2ab+), astroglial (GFAP+), and oligodendroglial (GalC+) phenotype. Differentiated hNPCs showed functional properties of neurons, such as sodium channels, action potentials and production of the neurotransmitters glutamate and GABA. Co-culture of hNPCs with fetal cortical cultures, MEFs and PA6 cells increased neurogenesis of hNPCs in vitro, while only MEFs and PA6 cells also led to a morphological and functional neurogenic maturation. Together we provide a first detailed characterization of the phenotype and differentiation potential of human adult hNPCs in vitro. Our findings reinforce the emerging view that the differentiation capacity of adult hNPCs is critically influenced by non-neuronal mesodermal feeder cells.


Assuntos
Hipocampo/crescimento & desenvolvimento , Hipocampo/fisiologia , Mesoderma/citologia , Células-Tronco/fisiologia , Adolescente , Adulto , Animais , Astrócitos/metabolismo , Contagem de Células , Diferenciação Celular/fisiologia , Proliferação de Células , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Técnicas de Cocultura , Dopamina/metabolismo , Eletrofisiologia , Feminino , Fibroblastos/metabolismo , Citometria de Fluxo , Ácido Glutâmico/metabolismo , Hipocampo/citologia , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Pessoa de Meia-Idade , RNA/biossíntese , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serotonina/metabolismo , Células Estromais/metabolismo , Telomerase/metabolismo , Ácido gama-Aminobutírico/metabolismo
19.
Biomaterials ; 27(17): 3265-73, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16494940

RESUMO

In human body ascorbic acid plays an essential role in the synthesis and function of skeletal tissues and immune system factors. Ascorbic acid is also a major physiological antioxidant, repairing oxidatively damaged biomolecules, preventing the formation of excessive reactive oxygen species or scavenging these species. We recently reported the synthesis of ascorbic acid-functionalized polymers in which the antioxidant features of the pendant ascorbic acid groups was preserved. In the present work we demonstrate that ascorbic acid-functionalized poly(methyl methacrylate) (AA-PMMA) can modulate the proliferation and osteogenic differentiation of early and late-passage bone marrow-derived human mesenchymal stem cells (MSCs). The covalently coupled ascorbic acid impacted MSCs differently than when ascorbic acid was presented to the cells in soluble form. At optimal concentration, the covalently coupled ascorbic acid and soluble ascorbic acid synergistically promoted and retained the ability of MSCs to respond to osteogenic stimulation over extensive cell expansions in vitro. In the presence of soluble ascorbic acid, AA-PMMA films prepared at optimal concentrations (0.1 mg/ml in the present study) showed a significant promotive effect over other concentrations and tissue culture plastic (TCP) with respect to osteogenic differentiation of both EP (young) and LP (old) MSCs. These results suggest that the coupled ascorbic acid is acting mainly at the extracellular level and, at optimal concentrations, the immobilized extracellular ascorbic acid and soluble ascorbic acid synergistically promote osteogenic differentiation of MSCs. Importantly, the covalently coupled ascorbic acid on the films of optimal concentration was able to preserve the capacity of MSCs to undergo osteogenic differentiation in vitro. These results suggest an important role for functionalized biomaterials with antioxidant features in control of cell physiology and cell aging phenomena.


Assuntos
Ácido Ascórbico/metabolismo , Materiais Biocompatíveis/química , Células da Medula Óssea/citologia , Regulação da Expressão Gênica , Mesoderma/citologia , Células-Tronco/citologia , Envelhecimento , Antioxidantes/química , Ácido Ascórbico/química , Diferenciação Celular , Proliferação de Células , Colágeno/química , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Modelos Químicos , Modelos Estatísticos , Músculo Esquelético/metabolismo , Polímeros/química , Polimetil Metacrilato/química , RNA/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Propriedades de Superfície
20.
Dev Biol ; 285(1): 252-71, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16039643

RESUMO

The hindbrain and cranial paraxial mesoderm have been implicated in the induction and patterning of the inner ear, but the precise role of the two tissues in these processes is still not clear. We have addressed these questions using the vitamin-A-deficient (VAD) quail model, in which VAD embryos lack the posterior half of the hindbrain that normally lies next to the inner ear. Using a battery of molecular markers, we show that the anlagen of the inner ear, the otic placode, is induced in VAD embryos in the absence of the posterior hindbrain. By performing grafting and ablation experiments in chick embryos, we also show that cranial paraxial mesoderm which normally lies beneath the presumptive otic placode is necessary for otic placode induction and that paraxial mesoderm from other locations cannot induce the otic placode. Two members of the fibroblast growth factor family, FGF3 and FGF19, continue to be expressed in this mesodermal population in VAD embryos, and these may be responsible for otic placode induction in the absence of the posterior hindbrain. Although the posterior hindbrain is not required for otic placode induction in VAD embryos, the subsequent patterning of the inner ear is severely disrupted. Several regional markers of the inner ear, such as Pax2, EphA4, SOHo1 and Wnt3a, are incorrectly expressed in VAD otocysts, and the sensory patches and vestibulo-acoustic ganglia are either greatly reduced or absent. Exogenous application of retinoic acid prior to 30 h of development is able rescue the VAD phenotype. By performing such rescue experiments before and after 30 h of development, we show that the inner ear defects of VAD embryos correlate with the absence of the posterior hindbrain. These results show that induction and patterning of the inner ear are governed by separate developmental processes that can be experimentally uncoupled from each other.


Assuntos
Orelha Interna/embriologia , Rombencéfalo/embriologia , Deficiência de Vitamina A/embriologia , Animais , Apoptose , Sequência de Bases , Padronização Corporal/genética , Padronização Corporal/fisiologia , Coturnix/embriologia , Coturnix/genética , Coturnix/fisiologia , DNA Complementar/genética , Orelha Interna/inervação , Indução Embrionária/genética , Indução Embrionária/fisiologia , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Mesoderma/citologia , Mesoderma/fisiologia , Modelos Animais , Fenótipo , Rombencéfalo/anormalidades , Rombencéfalo/fisiologia , Transdução de Sinais , Deficiência de Vitamina A/genética , Deficiência de Vitamina A/fisiopatologia
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