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1.
J Cell Biochem ; 125(4): e30541, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38372186

RESUMO

Epithelial cells (ECs) have been proposed to contribute to myofibroblasts or fibroblasts through epithelial-mesenchymal transition (EMT) during renal fibrosis. However, since EMT may occur dynamically, transiently, and reversibly during kidney fibrosis, conventional lineage tracing based on Cre-loxP recombination in renal ECs could hardly capture the transient EMT activity, yielding inconsistent results. Moreover, previous EMT research has primarily focused on renal proximal tubule ECs, with few reports of distal tubules and collecting ducts. Here, we generated dual recombinases-mediated genetic lineage tracing systems for continuous monitoring of transient mesenchymal gene expression in E-cadherin+ and EpCAM+ ECs of distal tubules and collecting ducts during renal fibrosis. Activation of key EMT-inducing transcription factor (EMT-TF) Zeb1 and mesenchymal markers αSMA, vimentin, and N-cadherin, were investigated following unilateral ureteral obstruction (UUO). Our data revealed that E-cadherin+ and EpCAM+ ECs did not transdifferentiate into myofibroblasts, nor transiently expressed these mesenchymal genes during renal fibrosis. In contrast, in vitro a large amount of cultured renal ECs upregulated mesenchymal genes in response to TGF-ß, a major inducer of EMT.


Assuntos
Transição Epitelial-Mesenquimal , Nefropatias , Humanos , Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Fibrose , Nefropatias/metabolismo , Células Epiteliais/metabolismo , Caderinas/genética , Caderinas/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
2.
Food Chem ; 442: 138474, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38245982

RESUMO

Fucoxanthin is a xanthophyll carotenoid that possesses potent antioxidant, anti-obesity, and anti-tumor properties. However, its limited solubility in water and susceptibility to degradation create challenges for its application. In this study, a microfluidic coaxial electrospinning technique was used to produce core-shell zein-gelatin nanofibers for encapsulating fucoxanthin, enhancing its bioavailability, and improving its stability. In comparison to uniaxially-loaded fucoxanthin nanofibers, the encapsulation efficiency of fucoxanthin reached 98.58 % at a core-shell flow rate ratio of 0.26:1, representing a 14.29 % improvement. The photostability of the nanofibers increased by 74.59 % after three days, UV stability increased by 38.82 % after 2 h, and temperature stability also significantly improved, demonstrating a protective effect under harsh environmental conditions (P < 0.05). Additionally, nanofibers effectively alleviated oleic acid-induced reactive oxygen species production and reduced fluorescence intensity by 54.76 %. MTT experiments indicated great biocompatibility of the nanofibers, effectively mitigating mitochondrial membrane potential polarization and lipid accumulation in HepG2 cells. Overall, the microfluidic coaxial electrospinning technique enables promising applications of fucoxanthin delivery in the food industry.


Assuntos
Nanofibras , Microfluídica , Xantofilas/farmacologia , Lipídeos
4.
J Cell Biol ; 221(6)2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35482005

RESUMO

Tissue-resident macrophages play essential functions in the maintenance of tissue homeostasis and repair. Recently, the endocardium has been reported as a de novo hemogenic site for the contribution of hematopoietic cells, including cardiac macrophages, during embryogenesis. These observations challenge the current consensus that hematopoiesis originates from the hemogenic endothelium within the yolk sac and dorsal aorta. Whether the developing endocardium has such a hemogenic potential requires further investigation. Here, we generated new genetic tools to trace endocardial cells and reassessed their potential contribution to hematopoietic cells in the developing heart. Fate-mapping analyses revealed that the endocardium contributed minimally to cardiac macrophages and circulating blood cells. Instead, cardiac macrophages were mainly derived from the endothelium during primitive/transient definitive (yolk sac) and definitive (dorsal aorta) hematopoiesis. Our findings refute the concept of endocardial hematopoiesis, suggesting that the developing endocardium gives rise minimally to hematopoietic cells, including cardiac macrophages.


Assuntos
Linhagem da Célula , Coração , Macrófagos , Miocárdio , Animais , Aorta/citologia , Endocárdio/citologia , Coração/embriologia , Hematopoese/genética , Miocárdio/citologia , Saco Vitelino/citologia
5.
Nat Commun ; 11(1): 2163, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358530

RESUMO

Angiogenesis is a necessary process for solid tumor growth. Cellular markers for endothelial cell proliferation are potential targets for identifying the vasculature of tumors in homeostasis. Here we customize the behaviors of engineered cells to recognize Apj, a surface marker of the neovascular endothelium, using synthetic Notch (synNotch) receptors. We designed apelin-based synNotch receptors (AsNRs) that can specifically interact with Apj and then stimulate synNotch pathways. Cells engineered with AsNRs have the ability to sense the proliferation of endothelial cells (ECs). Designed for different synNotch pathways, engineered cells express different proteins to respond to angiogenic signals; therefore, angiogenesis can be detected by cells engineered with AsNRs. Furthermore, T cells customized with AsNRs can sense the proliferation of vascular endothelial cells. As solid tumors generally require vascular support, AsNRs are potential tools for the detection and therapy of a variety of solid tumors in adults.


Assuntos
Apelina/química , Apelina/metabolismo , Neovascularização Patológica/metabolismo , Receptores Notch/química , Receptores Notch/metabolismo , Animais , Receptores de Apelina/metabolismo , Western Blotting , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/fisiologia , Células Endoteliais/metabolismo , Citometria de Fluxo , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Imunoterapia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
6.
Nat Genet ; 51(4): 728-738, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30778223

RESUMO

Characterizing the stem cells responsible for lung repair and regeneration is important for the treatment of pulmonary diseases. Recently, a unique cell population located at the bronchioalveolar-duct junctions has been proposed to comprise endogenous stem cells for lung regeneration. However, the role of bronchioalveolar stem cells (BASCs) in vivo remains debated, and the contribution of such cells to lung regeneration is not known. Here we generated a genetic lineage-tracing system that uses dual recombinases (Cre and Dre) to specifically track BASCs in vivo. Fate-mapping and clonal analysis showed that BASCs became activated and responded distinctly to different lung injuries, and differentiated into multiple cell lineages including club cells, ciliated cells, and alveolar type 1 and type 2 cells for lung regeneration. This study provides in vivo genetic evidence that BASCs are bona fide lung epithelial stem cells with deployment of multipotency and self-renewal during lung repair and regeneration.


Assuntos
Bronquíolos/fisiologia , Líquido da Lavagem Broncoalveolar/citologia , Pulmão/fisiologia , Células-Tronco Multipotentes/fisiologia , Regeneração/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Células Cultivadas , Células Epiteliais/fisiologia , Genótipo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
7.
Cell Rep ; 25(5): 1241-1254.e5, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30380415

RESUMO

Identification of cellular surface markers that distinguish tumorous from normal vasculature is important for the development of tumor vessel-targeted therapy. Here, we show that Apj, a G protein-coupled receptor, is highly enriched in tumor endothelial cells but absent from most endothelial cells of adult tissues in homeostasis. By genetic targeting using Apj-CreER and Apj-DTRGFP-Luciferase, we demonstrated that hypoxia-VEGF signaling drives expansion of Apj+ tumor vessels and that targeting of these vessels, genetically and pharmacologically, remarkably inhibits tumor angiogenesis and restricts tumor growth. These in vivo findings implicate Apj+ vessels as a key driver of pathological angiogenesis and identify Apj+ endothelial cells as an important therapeutic target for the anti-angiogenic treatment of tumors.


Assuntos
Receptores de Apelina/metabolismo , Vasos Sanguíneos/patologia , Terapia de Alvo Molecular , Neoplasias/patologia , Envelhecimento/metabolismo , Animais , Vasos Sanguíneos/embriologia , Vasos Sanguíneos/metabolismo , Hipóxia Celular , Proliferação de Células , Células Endoteliais/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Neoplasias/irrigação sanguínea , Neovascularização Patológica , Transdução de Sinais , Hipóxia Tumoral , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Nat Protoc ; 13(10): 2217-2246, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30250288

RESUMO

Unraveling the fates of resident stem cells during tissue regeneration is an important objective in clinical and basic research. Genetic lineage tracing based on Cre-loxP recombination provides an effective strategy for inferring cell fate and cell conversion in vivo. However, the determination of the exact fates of resident stem cells or their derivatives in disease states and during tissue regeneration remains controversial in many fields of study, partly because of technical limitations associated with Cre-based lineage tracing, such as, for example, off-target labeling. Recently, we generated a new lineage-tracing platform we named DeaLT (dual-recombinase-activated lineage tracing) that uses the Dre-rox recombination system to enhance the precision of Cre-mediated lineage tracing. Here, we describe as an example a detailed protocol using DeaLT to trace the fate of c-Kit+ cardiac stem cells and their derivatives, in the absence of any interference from nontarget cells such as cardiomyocytes, during organ homeostasis and after tissue injury. This lineage-tracing protocol can also be used to delineate the fate of resident stem cells of other organ systems, and takes ~10 months to complete, from mouse crossing to final tissue analysis.


Assuntos
Rastreamento de Células/métodos , Miocárdio/citologia , Proteínas Proto-Oncogênicas c-kit/análise , Células-Tronco/citologia , Animais , Linhagem da Célula , Feminino , Técnicas de Introdução de Genes/métodos , Técnicas de Genotipagem/métodos , Traumatismos Cardíacos/genética , Traumatismos Cardíacos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Miocárdio/metabolismo , Miocárdio/patologia , Proteínas Proto-Oncogênicas c-kit/genética , Recombinação Genética , Células-Tronco/metabolismo , Células-Tronco/patologia
9.
Circ Res ; 123(1): 86-99, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29764841

RESUMO

RATIONALE: Organs of the body require vascular networks to supply oxygen and nutrients and maintain physiological function. The blood vessels of different organs are structurally and functionally heterogeneous in nature. To more precisely dissect their distinct in vivo function in individual organs, without potential interference from off-site targets, it is necessary to genetically target them in an organ-specific manner. OBJECTIVE: The objective of this study was to generate a genetic system that targets vascular endothelial cells in an organ- or tissue-specific manner and to exemplify the potential application of intersectional genetics for precise, target-specific gene manipulation in vivo. METHODS AND RESULTS: We took advantage of 2 orthogonal recombination systems, Dre-rox and Cre-loxP, to create a genetic targeting system based on intersectional genetics. Using this approach, Cre activity was only detectable in cells that had expressed both Dre and Cre. Applying this new system, we generated a coronary endothelial cell-specific Cre (CoEC-Cre) and a brain endothelial cell-specific Cre (BEC-Cre). Through lineage tracing, gene knockout and overexpression experiments, we demonstrated that CoEC-Cre and BEC-Cre efficiently and specifically target blood vessels in the heart and brain, respectively. By deletion of vascular endothelial growth factor receptor 2 using BEC-Cre, we showed that vascular endothelial growth factor signaling regulates angiogenesis in the central nervous system and also controls the integrity of the blood-brain barrier. CONCLUSIONS: We provide 2 examples to illustrate the use of intersectional genetics for more precise gene targeting in vivo, namely manipulation of genes in blood vessels of the heart and brain. More broadly, this system provides a valuable strategy for tissue-specific gene manipulation that can be widely applied to other fields of biomedical research.


Assuntos
Vasos Sanguíneos , Encéfalo/irrigação sanguínea , Vasos Coronários , Marcação de Genes/métodos , Animais , Barreira Hematoencefálica , Hipóxia Celular , Células Endoteliais , Técnicas de Inativação de Genes , Hibridização In Situ/métodos , Camundongos , Neovascularização Fisiológica , Especificidade de Órgãos , Receptores de Fatores de Crescimento do Endotélio Vascular/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia
10.
Mar Drugs ; 16(1)2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29346329

RESUMO

Thirty-one isolates belonging to eight genera in seven orders were identified from 141 strains that were isolated from several marine plants. Alternaria sp. and Fusarium sp. were found to be the predominant fungi. Evaluation of the anti-phytopathogenic bacterial and fungal activities, as well as the cytotoxicity of these 31 extracts, revealed that most of them displayed different levels of bioactivities. Due to their interesting bioactivities, two fungal strains-Fusarium equiseti (P18) and Alternaria sp. (P8)-were selected for chemical investigation and compounds 1-4 were obtained. The structure of 1 was elucidated by 1D and 2D NMR analysis, as well as high-resolution electrospray ionization mass spectroscopy (HRESIMS), and the absolute configuration of its stereogenic carbon (C-11) was established by comparison of the experimental and calculated electronic circular-dichroism (ECD) spectra. Moreover, alterperylenol (4) exhibited antibacterial activity against Clavibacter michiganensis with a minimum inhibitory concentration (MIC) of 1.95 µg/mL, which was 2-fold stronger than that of streptomycin sulfate. Additionally, an antibacterial mechanism study revealed that 4 caused membrane hyperpolarization without evidence of destruction of cell membrane integrity. Furthermore, stemphyperylenol (3) displayed potent antifungal activity against Pestallozzia theae and Alternaria brassicicola with MIC values equal to those of carbendazim. The cytotoxicity of 1 and 2 against human lung carcinoma (A-549), human cervical carcinoma (HeLa), and human hepatoma (HepG2) cell lines were also evaluated.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Organismos Aquáticos/química , Misturas Complexas/farmacologia , Citotoxinas/farmacologia , Fungos/química , Fungos/metabolismo , Células A549 , Alternaria/química , Antibacterianos/química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Misturas Complexas/química , Citotoxinas/química , Fungos/efeitos dos fármacos , Fusarium/química , Células HeLa , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana/métodos
11.
Nat Commun ; 8(1): 87, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28729659

RESUMO

Noncompaction cardiomyopathy is characterized by the presence of extensive trabeculations, which could lead to heart failure and malignant arrhythmias. How trabeculations resolve to form compact myocardium is poorly understood. Elucidation of this process is critical to understanding the pathophysiology of noncompaction disease. Here we use genetic lineage tracing to mark the Nppa+ or Hey2+ cardiomyocytes as trabecular and compact components of the ventricular wall. We find that Nppa+ and Hey2+ cardiomyocytes, respectively, from the endocardial and epicardial zones of the ventricular wall postnatally. Interposed between these two postnatal layers is a hybrid zone, which is composed of cells derived from both the Nppa+ and Hey2+ populations. Inhibition of the fetal Hey2+ cell contribution to the hybrid zone results in persistence of excessive trabeculations in postnatal heart. Our findings indicate that the expansion of Hey2+ fetal compact component, and its contribution to the hybrid myocardial zone, are essential for normal formation of the ventricular walls.Fetal trabecular muscles in the heart undergo a poorly described morphogenetic process that results into a solidified compact myocardium after birth. Tian et al. show that cardiomyocytes in the fetal compact layer also contribute to this process, forming a hybrid myocardial zone that is composed of cells derived from both trabecular and compact layers.


Assuntos
Cardiomiopatias/embriologia , Ventrículos do Coração/embriologia , Animais , Animais Recém-Nascidos , Fator Natriurético Atrial , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Cardiomiopatias/congênito , Cardiomiopatias/metabolismo , Linhagem da Célula , Coração/embriologia , Coração/crescimento & desenvolvimento , Cardiopatias Congênitas/embriologia , Cardiopatias Congênitas/metabolismo , Ventrículos do Coração/crescimento & desenvolvimento , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Camundongos , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Peptídeo Natriurético Tipo C/metabolismo , Organogênese , Precursores de Proteínas/metabolismo , Proteínas Repressoras/metabolismo
12.
Front Microbiol ; 8: 289, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28289406

RESUMO

Phenazine and its derivatives are very important secondary metabolites produced from Pseudomonas spp. and have exhibited broad-spectrum antifungal and antibacterial activities. However, till date, there are few reports about marine derived Pseudomonas and its production of phenazine metabolites. In this study, we isolated a marine Pseudomonas aeruginosa strain PA31x which produced natural product inhibiting the growth of Vibrio anguillarum C312, one of the most serious bacterial pathogens in marine aquaculture. Combining high-resolution electro-spray-ionization mass spectroscopy and nuclear magnetic resonance spectroscopy analyses, the functional compound against V. anguillarum was demonstrated to be phenazine-1-carboxylic acid (PCA), an important phenazine derivative. Molecular studies indicated that the production of PCA by P. aeruginosa PA31x was determined by gene clusters phz1 and phz2 in its genome. Electron microscopic results showed that treatment of V. anguillarum with PCA developed complete lysis of bacterial cells with fragmented cytoplasm being released to the surrounding environment. Additional evidence indicated that reactive oxygen species generation preceded PCA-induced microbe and cancer cell death. Notably, treatment with PCA gave highly significant protective activities against the development of V. anguillarum C312 on zebrafish. Additionally, the marine derived PCA was further found to effectively inhibit the growth of agricultural pathogens, Acidovorax citrulli NP1 and Phytophthora nicotianae JM1. Taken together, this study reveals that marine Pseudomonas derived PCA carries antagonistic activities against both aquacultural and agricultural pathogens, which broadens the application fields of PCA.

13.
Circ Res ; 118(12): 1880-93, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27056912

RESUMO

RATIONALE: There is persistent uncertainty regarding the developmental origins of coronary vessels, with 2 principal sources suggested as ventricular endocardium or sinus venosus (SV). These 2 proposed origins implicate fundamentally distinct mechanisms of vessel formation. Resolution of this controversy is critical for deciphering the programs that result in the formation of coronary vessels and has implications for research on therapeutic angiogenesis. OBJECTIVE: To resolve the controversy over the developmental origin of coronary vessels. METHODS AND RESULTS: We first generated nuclear factor of activated T cells (Nfatc1)-Cre and Nfatc1-Dre lineage tracers for endocardium labeling. We found that Nfatc1 recombinases also label a significant portion of SV endothelial cells in addition to endocardium. Therefore, restricted endocardial lineage tracing requires a specific marker that distinguishes endocardium from SV. By single-cell gene expression analysis, we identified a novel endocardial gene natriuretic peptide receptor 3 (Npr3). Npr3 is expressed in the entirety of the endocardium but not in the SV. Genetic lineage tracing based on Npr3-CreER showed that endocardium contributes to a minority of coronary vessels in the free walls of embryonic heart. Intersectional genetic lineage tracing experiments demonstrated that endocardium minimally contributes to coronary endothelium in the embryonic ventricular free walls. CONCLUSIONS: Our study suggested that SV, but not endocardium, is the major origin for coronary endothelium in the embryonic ventricular free walls. This work thus resolves the recent controversy over the developmental origin of coronary endothelium, providing the basis for studying coronary vessel formation and regeneration after injury.


Assuntos
Linhagem da Célula , Vasos Coronários/embriologia , Endocárdio/embriologia , Endotélio Vascular/metabolismo , Ventrículos do Coração/embriologia , Animais , Vasos Coronários/citologia , Vasos Coronários/metabolismo , Endocárdio/citologia , Endocárdio/metabolismo , Endotélio Vascular/citologia , Ventrículos do Coração/citologia , Ventrículos do Coração/metabolismo , Camundongos , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Receptores do Fator Natriurético Atrial/genética , Receptores do Fator Natriurético Atrial/metabolismo
14.
Nat Genet ; 48(5): 537-43, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27019112

RESUMO

The hepatic vasculature is essential for liver development, homeostasis and regeneration, yet the developmental program of hepatic vessel formation and the embryonic origin of the liver vasculature remain unknown. Here we show in mouse that endocardial cells form a primitive vascular plexus surrounding the liver bud and subsequently contribute to a substantial portion of the liver vasculature. Using intersectional genetics, we demonstrate that the endocardium of the sinus venosus is a source for the hepatic plexus. Inhibition of endocardial angiogenesis results in reduced endocardial contribution to the liver vasculature and defects in liver organogenesis. We conclude that a substantial portion of liver vessels derives from the endocardium and shares a common developmental origin with coronary arteries.


Assuntos
Linhagem da Célula , Endocárdio/embriologia , Fígado/embriologia , Animais , Vasos Coronários/embriologia , Endocárdio/citologia , Endocárdio/metabolismo , Átrios do Coração/embriologia , Átrios do Coração/metabolismo , Ventrículos do Coração/embriologia , Ventrículos do Coração/metabolismo , Fígado/irrigação sanguínea , Circulação Hepática , Camundongos , Morfogênese , Fatores de Transcrição NFATC/metabolismo , Neovascularização Fisiológica
15.
Development ; 143(6): 936-49, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26893347

RESUMO

Although the mammalian heart can regenerate during the neonatal stage, this endogenous regenerative capacity is lost with age. Importantly, replication of cardiomyocytes has been found to be the key mechanism responsible for neonatal cardiac regeneration. Unraveling the transcriptional regulatory network for inducing cardiomyocyte replication will, therefore, be crucial for the development of novel therapies to drive cardiac repair after injury. Here, we investigated whether the key cardiac transcription factor GATA4 is required for neonatal mouse heart regeneration. Using the neonatal mouse heart cryoinjury and apical resection models with an inducible loss of GATA4 specifically in cardiomyocytes, we found severely depressed ventricular function in the Gata4-ablated mice (mutant) after injury. This was accompanied by reduced cardiomyocyte replication. In addition, the mutant hearts displayed impaired coronary angiogenesis and increased hypertrophy and fibrosis after injury. Mechanistically, we found that the paracrine factor FGF16 was significantly reduced in the mutant hearts after injury compared with littermate controls and was directly regulated by GATA4. Cardiac-specific overexpression of FGF16 via adeno-associated virus subtype 9 (AAV9) in the mutant hearts partially rescued the cryoinjury-induced cardiac hypertrophy, promoted cardiomyocyte replication and improved heart function after injury. Altogether, our data demonstrate that GATA4 is required for neonatal heart regeneration through regulation of Fgf16, suggesting that paracrine factors could be of potential use in promoting myocardial repair.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Fator de Transcrição GATA4/metabolismo , Coração/fisiopatologia , Regeneração , Animais , Animais Recém-Nascidos , Sequência de Bases , Proliferação de Células , Dependovirus/metabolismo , Deleção de Genes , Camundongos Knockout , Dados de Sequência Molecular , Mutação/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Neovascularização Fisiológica , Especificidade de Órgãos , Fenótipo
16.
Cell Res ; 26(1): 119-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26634606

RESUMO

Cardiac cells marked by c-Kit or Kit, dubbed cardiac stem cells (CSCs), are in clinical trials to investigate their ability to stimulate cardiac regeneration and repair. These studies were initially motivated by the purported cardiogenic activity of these cells. Recent lineage tracing studies using Kit promoter to drive expression of the inducible Cre recombinase showed that these CSCs had highly limited cardiogenic activity, inadequate to support efficient cardiac repair. Here we reassess the lineage tracing data by investigating the identity of cells immediately after Cre labeling. Our instant lineage tracing approach identifies Kit-expressing cardiomyocytes, which are labeled immediately after tamoxifen induction. In combination with long-term lineage tracing experiments, these data reveal that the large majority of long-term labeled cardiomyocytes are pre-existing Kit-expressing cardiomyocytes rather than cardiomyocytes formed de novo from CSCs. This study presents a new interpretation for the contribution of Kit(+) cells to cardiomyocytes and shows that Kit genetic lineage tracing over-estimates the cardiogenic activity of Kit(+) CSCs.


Assuntos
Coração/fisiologia , Miócitos Cardíacos/citologia , Proteínas Proto-Oncogênicas c-kit/análise , Regeneração , Células-Tronco/citologia , Animais , Linhagem da Célula , Células Cultivadas , Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/citologia , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Células-Tronco/metabolismo
17.
Nat Med ; 21(8): 866-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26168292

RESUMO

Unraveling the fate specification of resident stem cells during lung regeneration is of clinical importance. It has been reported that c-kit(+) progenitor cells resident in the human lung regenerate epithelial lineages upon transplantation into injured mouse lung. Here we test the lineage potential of c-kit(+) cells by inducible genetic lineage tracing. We find that c-kit(+) cells do not contribute to lung epithelium during homeostasis and repair, and instead maintain a vascular endothelial cell fate. These findings call attention to the clinical application of c-kit(+) stem cells as lung epithelial progenitors for the treatment of pulmonary disease.


Assuntos
Células Endoteliais/fisiologia , Células Epiteliais/fisiologia , Pulmão/citologia , Proteínas Proto-Oncogênicas c-kit/análise , Animais , Linhagem da Célula , Feminino , Homeostase , Masculino , Camundongos , Células-Tronco/fisiologia
18.
Nat Commun ; 6: 6020, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25597280

RESUMO

Under pathophysiological conditions in adults, endothelial cells (ECs) sprout from pre-existing blood vessels to form new ones by a process termed angiogenesis. During embryonic development, Apelin (APLN) is robustly expressed in vascular ECs. In adult mice, however, APLN expression in the vasculature is significantly reduced. Here we show that APLN expression is reactivated in adult ECs after ischaemia insults. In models of both injury ischaemia and tumor angiogenesis, we find that Apln-CreER genetically labels sprouting but not quiescent vasculature. By leveraging this specific activity, we demonstrate that abolishment of the VEGF-VEGFR2 signalling pathway as well as ablation of sprouting ECs diminished tumour vascularization and growth without compromising vascular homeostasis in other organs. Collectively, we show that Apln-CreER distinguishes sprouting vessels from stabilized vessels in multiple pathological settings. The Apln-CreER line described here will greatly aid future mechanistic studies in both vascular developmental biology and adult vascular diseases.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neovascularização Fisiológica/fisiologia , Adipocinas , Animais , Apelina , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Feminino , Membro Posterior , Peptídeos e Proteínas de Sinalização Intercelular/genética , Isquemia , Masculino , Camundongos , Neovascularização Fisiológica/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
19.
PLoS One ; 9(10): e109493, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25299188

RESUMO

ATP-dependent SWI/SNF chromatin remodeling complexes utilize ATP hydrolysis to non-covalently change nucleosome-DNA interactions and are essential in stem cell development, organogenesis, and tumorigenesis. Biochemical studies show that SWI/SNF in mammalian cells can be divided into two subcomplexes BAF and PBAF based on the subunit composition. ARID2 or BAF200 has been defined as an intrinsic subunit of PBAF complex. However, the function of BAF200 in vivo is not clear. To dissect the possible role of BAF200 in regulating embryogenesis and organ development, we generated BAF200 mutant mice and found they were embryonic lethal. BAF200 mutant embryos exhibited multiple cardiac defects including thin myocardium, ventricular septum defect, common atrioventricular valve, and double outlet right ventricle around E14.5. Moreover, we also detected reduced intramyocardial coronary arteries in BAF200 mutants, suggesting that BAF200 is required for proper migration and differentiation of subepicardial venous cells into arterial endothelial cells. Our work revealed that PBAF complex plays a critical role in heart morphogenesis and coronary artery angiogenesis.


Assuntos
Diferenciação Celular/fisiologia , Proteínas Cromossômicas não Histona/metabolismo , Vasos Coronários/crescimento & desenvolvimento , Vasos Coronários/fisiologia , Desenvolvimento Embrionário/fisiologia , Coração/crescimento & desenvolvimento , Coração/fisiologia , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular/genética , Movimento Celular/genética , Movimento Celular/fisiologia , Proteínas Cromossômicas não Histona/genética , Vasos Coronários/metabolismo , Desenvolvimento Embrionário/genética , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Miocárdio/metabolismo , Neovascularização Fisiológica/fisiologia , Organogênese/genética , Organogênese/fisiologia , Fatores de Transcrição/genética
20.
J Clin Invest ; 124(11): 4899-914, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25271623

RESUMO

Coronary arteries (CAs) stem from the aorta at 2 highly stereotyped locations, deviations from which can cause myocardial ischemia and death. CA stems form during embryogenesis when peritruncal blood vessels encircle the cardiac outflow tract and invade the aorta, but the underlying patterning mechanisms are poorly understood. Here, using murine models, we demonstrated that VEGF-C-deficient hearts have severely hypoplastic peritruncal vessels, resulting in delayed and abnormally positioned CA stems. We observed that VEGF-C is widely expressed in the outflow tract, while cardiomyocytes develop specifically within the aorta at stem sites where they surround maturing CAs in both mouse and human hearts. Mice heterozygous for islet 1 (Isl1) exhibited decreased aortic cardiomyocytes and abnormally low CA stems. In hearts with outflow tract rotation defects, misplaced stems were associated with shifted aortic cardiomyocytes, and myocardium induced ectopic connections with the pulmonary artery in culture. These data support a model in which CA stem development first requires VEGF-C to stimulate vessel growth around the outflow tract. Then, aortic cardiomyocytes facilitate interactions between peritruncal vessels and the aorta. Derangement of either step can lead to mispatterned CA stems. Studying this niche for cardiomyocyte development, and its relationship with CAs, has the potential to identify methods for stimulating vascular regrowth as a treatment for cardiovascular disease.


Assuntos
Aorta Torácica/citologia , Vasos Coronários/embriologia , Miócitos Cardíacos/fisiologia , Fator C de Crescimento do Endotélio Vascular/fisiologia , Animais , Padronização Corporal , Diferenciação Celular , Movimento Celular , Vasos Coronários/citologia , Feminino , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neovascularização Fisiológica , Artéria Pulmonar/fisiologia , Técnicas de Cultura de Tecidos
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