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1.
Int J Mol Sci ; 24(20)2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37894861

RESUMO

Various kinds of plastics have been developed over the past century, vastly improving the quality of life. However, the indiscriminate production and irresponsible management of plastics have led to the accumulation of plastic waste, emerging as a pressing environmental concern. To establish a clean and sustainable plastic economy, plastic recycling becomes imperative to mitigate resource depletion and replace non-eco-friendly processes, such as incineration. Although chemical and mechanical recycling technologies exist, the prevalence of composite plastics in product manufacturing complicates recycling efforts. In recent years, the biodegradation of plastics using enzymes and microorganisms has been reported, opening a new possibility for biotechnological plastic degradation and bio-upcycling. This review provides an overview of microbial strains capable of degrading various plastics, highlighting key enzymes and their role. In addition, recent advances in plastic waste valorization technology based on systems metabolic engineering are explored in detail. Finally, future perspectives on systems metabolic engineering strategies to develop a circular plastic bioeconomy are discussed.


Assuntos
Engenharia Metabólica , Plásticos , Plásticos/química , Qualidade de Vida , Biodegradação Ambiental , Biotecnologia , Reciclagem
2.
Mol Pharm ; 17(6): 2034-2043, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32364395

RESUMO

Ischemic heart disease, especially myocardial infarction (MI), is the leading cause of death worldwide. Apoptotic mechanisms are thought to play a significant role in cardiomyocyte death after MI. Increased production of heat shock proteins (Hsps) in cardiomyocytes is a normal response to promote tolerance and to reduce cell damage. Hsp27 is considered to be a therapeutic option for the treatment of ischemic heart disease due to its protective effects on hypoxia-induced apoptosis. Despite its antiapoptotic effects, the lack of strategies to deliver Hsp27 to the heart tissue in vivo limits its clinical applicability. In this study, we utilized an antibody against the angiotensin II type 1 (AT1) receptor, which is expressed immediately after ischemia/reperfusion in the heart of MI rats. To achieve cardiomyocyte-targeted Hsp27 delivery after ischemia/reperfusion, we employed the immunoglobulin-binding dimer ZZ, a modified domain of protein A, in conjunction with the AT1 receptor antibody. Using the AT1 receptor antibody, we achieved systemic delivery of ZZ-TAT-GFP fusion protein into the heart of MI rats. This approach enabled selective delivery of Hsp27 to cardiomyocytes, rescued cells from apoptosis, reduced the area of fibrosis, and improved cardiac function in the rat MI model, thus suggesting its applicability as a cardiomyocyte-targeted protein delivery system to inhibit apoptosis induced by ischemic injury.


Assuntos
Proteínas de Choque Térmico HSP27/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Animais , Anticorpos Monoclonais , Linhagem Celular Tumoral , Feminino , Proteínas de Choque Térmico HSP27/genética , Humanos , Infarto do Miocárdio/genética , Ratos , Receptor Tipo 1 de Angiotensina/genética
3.
Int J Mol Sci ; 20(10)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091659

RESUMO

Dysregulation of cellular energy metabolism is closely linked to cancer development and progression. Calorie or glucose restriction (CR or GR) inhibits energy-dependent pathways, including IGF-1/PI3K/Akt/mTOR, in cancer cells. However, alterations in proton dynamics and reversal of the pH gradient across the cell membrane, which results in intracellular alkalinization and extracellular acidification in cancer tissues, have emerged as important etiopathogenic factors. We measured glucose, lactate, and ATP production after GR, plant-derived CR-mimetic curcumin treatment, and curcumin plus GR in human hepatoma cells. Intracellular pH regulatory effects, in particular, protein-protein interactions within mTOR complex-1 and its structural change, were investigated. Curcumin treatment or GR mildly inhibited Na+/H+ exchanger-1 (NHE1). vATPase, monocarboxylate transporter (MCT)-1, and MCT4 level. Combination treatment with curcumin and GR further enhanced the inhibitory effects on these transporters and proton-extruding enzymes, with intracellular pH reduction. ATP and lactate production decreased according to pH change. Modeling of mTOR protein revealed structural changes upon treatments, and curcumin plus GR decreased binding of Raptor and GßL to mTOR, as well as of Rag A and Rag B to Raptor. Consequently, 4EBP1 phosphorylation was decreased and cell migration and proliferation were inhibited in a pH-dependent manner. Autophagy was increased by curcumin plus GR. In conclusion, curcumin treatment combined with GR may be a useful supportive approach for preventing intracellular alkalinization and cancer progression.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Curcumina/farmacologia , Glucose/deficiência , Neoplasias Hepáticas/metabolismo , Álcalis/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Glucose/metabolismo , Células Hep G2 , Humanos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteína Regulatória Associada a mTOR/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo
4.
EMBO Rep ; 16(5): 654-69, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25802403

RESUMO

The ETS factor ETV2 (aka ER71) is essential for the generation of the blood and vascular system, as ETV2 deficiency leads to a complete block in blood and endothelial cell formation and embryonic lethality in the mouse. However, the ETV2-mediated gene regulatory network and signaling governing hematopoietic and endothelial cell development are poorly understood. Here, we map ETV2 global binding sites and carry out in vitro differentiation of embryonic stem cells, and germ line and conditional knockout mouse studies to uncover mechanisms involved in the hemangiogenic fate commitment from mesoderm. We show that ETV2 binds to enhancers that specify hematopoietic and endothelial cell lineages. We find that the hemangiogenic progenitor population in the developing embryo can be identified as FLK1(high)PDGFRα(-). Notably, these hemangiogenic progenitors are exclusively sensitive to ETV2-dependent FLK1 signaling. Importantly, ETV2 turns on other Ets genes, thereby establishing an ETS hierarchy. Consequently, the hematopoietic and endothelial cell program initiated by ETV2 is maintained partly by other ETS factors through an ETS switching mechanism. These findings highlight the critical role that transient ETV2 expression plays in the regulation of hematopoietic and endothelial cell lineage specification and stability.


Assuntos
Células Sanguíneas/citologia , Células Sanguíneas/metabolismo , Diferenciação Celular , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Diferenciação Celular/genética , Linhagem da Célula/genética , Imunoprecipitação da Cromatina , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Imunofenotipagem , Masculino , Camundongos , Camundongos Knockout , Motivos de Nucleotídeos , Especificidade de Órgãos/genética , Matrizes de Pontuação de Posição Específica , Ligação Proteica , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo
5.
Exp Cell Res ; 341(2): 139-46, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26854694

RESUMO

In the endothelial recovery process, bone marrow-derived MSCs are a potential source of cells for both research and therapy, and their capacities to self-renew and to differentiate into all the cell types in the human body make them a promising therapeutic agent for remodeling cellular differentiation and a valuable resource for the treatment of many diseases. Based on the results provided in a miRNA database, we selected miRNAs with unique targets in cell fate-related signaling pathways. The tested miRNAs targeting GSK-3ß (miR-26a), platelet-derived growth factor receptor, and CD133 (miR-26a and miR-29b) induced MSC differentiation into functional ECs, whereas miRNAs targeting VEGF receptor (miR-15, miR-144, miR-145, and miR-329) inhibited MSC differentiation into ECs through VEGF stimulation. In addition, the expression levels of these miRNAs were correlated with in vivo physiological endothelial recovery processes. These findings indicate that the miRNA expression profile is distinct for cells in different stages of differentiation from MSCs to ECs and that specific miRNAs can function as regulators of endothelialization.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular/genética , Linhagem da Célula , Células Endoteliais/citologia , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Ratos Sprague-Dawley , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
6.
Bioorg Med Chem Lett ; 26(20): 5098-5102, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27614412

RESUMO

The restoration of damaged articular cartilage is a long-pursued goal in regenerative medicine. Chondrocyte-specific differentiation of mesenchymal stem cells (MSCs) may be an effective means of repairing damaged cartilage. We identified small molecule 6 with sulfonamide as an agent that promotes specific chondrogenic differentiation of human adipose-derived MSCs (hASCs). Unlike other chondrogenic differentiation media composed of various defined components, simply adding compound 6 into culture medium was sufficient to induce chondrogenesis in this study. In an animal osteoarthritis model, both the small molecule 6 and the 6-treated hASCs exhibited enhanced recovery of injured articular cartilage. This work provides new insight into MSC differentiation induced by small molecules and potential new therapeutic approaches for articular cartilage injury.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas , Sulfonamidas/farmacologia , Cartilagem Articular/citologia , Diferenciação Celular , Condrócitos/citologia , Meios de Cultura , Ensaio de Imunoadsorção Enzimática , Humanos , Células-Tronco Mesenquimais/citologia , Regeneração
7.
J Cell Biochem ; 116(4): 598-608, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25389122

RESUMO

The proliferation and migration of smooth muscle cells (SMCs) are considered to be key steps in the progression of atherosclerosis and restenosis. Certain stimuli, such as, interleukin-3 (IL-3) are known to stimulate proliferation and migration in vascular diseases. Meanwhile, microRNAs (miRs) have been revealed as critical modulators of various diseases in which miR-29b is known to regulate cell growth by targeting Mcl-1 and MMP2. However, roles of miR-29b in vascular smooth muscle cells remain almost unknown. We hypothesized that miR-29b may control the proliferation and migration processes induced by IL-3 stimulation by inhibiting its own specific targets in SMCs. MiR-29b significantly suppressed the proliferation and migration of SMCs through the inhibition of the signaling pathway related to Mcl-1 and MMP2. We also found that miR-29b expression levels significantly declined in balloon-injured rat carotid arteries and that the overexpression of miR-29b by local oligonucleotide delivery can inhibit neointimal formation. Consistent with the critical role of miR-29b in vitro, we observed down-regulated expression levels of Mcl-1 and MMP2 from the neointimal region. These results indicate that miR-29b suppressed the proliferation and migration of SMCs, possibly through the inhibition of Mcl-1 and MMP2, and suggest that miR-29b may serve as a useful therapeutic tool to treat cardiovascular diseases such as, atherosclerosis and restenosis.


Assuntos
Lesões das Artérias Carótidas/genética , Interleucina-3/farmacologia , MicroRNAs/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/fisiologia , Neointima/genética , Animais , Lesões das Artérias Carótidas/metabolismo , Movimento Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica , Metaloproteinase 2 da Matriz/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Miócitos de Músculo Liso/citologia , Ratos , Ratos Sprague-Dawley
8.
Biochem Biophys Res Commun ; 465(3): 349-55, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26253469

RESUMO

Under distinct pathological heart conditions, the expression of a single miRNA can display completely opposite patterns. However, the mechanism underlying the bidirectional regulation of a single miRNA and the clinical implications of this regulation remain largely unknown. To address this issue, we examined the regulation of miR-1, one of the most abundant miRNAs in the heart, during cardiac hypertrophy and ischemia/reperfusion (I/R). Our data indicated that different magnitudes and chronicities of ROS levels in cardiomyocytes resulted in differential expression of miR-1, subsequently altering the expression of myocardin. In animal models, the administration of a miR-1 mimic attenuated cardiac hypertrophy by suppressing the transverse aortic constriction-induced increase in myocardin expression, whereas the administration of anti-miR-1 ameliorated I/R-induced cardiac apoptosis and deterioration of heart function. Our findings indicated that a pathologic stimulus such as ROS can bidirectionally alter the expression of miRNA to contribute to the development of pathological conditions exhibiting distinct phenotypes and that the meticulous adjustment of the pathological miRNA levels is required to improve clinical outcomes.


Assuntos
Cardiomegalia/metabolismo , Insuficiência Cardíaca/metabolismo , MicroRNAs/metabolismo , Miocárdio/metabolismo , Proteínas Nucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transativadores/metabolismo , Animais , Apoptose , Cardiomegalia/genética , Células Cultivadas , Regulação da Expressão Gênica/genética , Insuficiência Cardíaca/genética , MicroRNAs/genética , Proteínas Nucleares/genética , Ratos , Ratos Sprague-Dawley , Transativadores/genética
9.
Mol Ther ; 22(6): 1110-1121, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24637455

RESUMO

Myocardial Ca(2+) overload induced by ischemia/reperfusion (I/R) is a major element of myocardial dysfunction in heart failure. Phospholipase C (PLC) plays important roles in the regulation of the phosphoinositol pathway and Ca(2+) homeostasis in various types of cells. Here, we investigated the protective role of PLCδ1 against myocardial I/R injury through the regulation of Ca(2+) homeostasis. To investigate its role, PLCδ1 was fused to Hph1, a cell-permeable protein transduction domain (PTD), and treated into rat neonatal cardiomyocytes and rat hearts under respective hypoxia-reoxygenation (H/R) and ischemia-reperfusion conditions. Treatment with Hph1-PLCδ1 significantly inhibited intracellular Ca(2+) overload, reactive oxygen species generation, mitochondrial permeability transition pore opening, and mitochondrial membrane potential elevation in H/R neonatal cardiomyocytes, resulting in the inhibition of apoptosis. Intravenous injections of Hph1-PLCδ1 in rats with I/R-injured myocardium caused significant reductions in infarct size and apoptosis and also improved systolic and diastolic cardiac functioning. Furthermore, a small ions profile obtained using time-of-flight secondary ion mass spectrometry showed that treatment with Hph1-PLCδ1 leads to significant recovery of calcium-related ions toward normal levels in I/R-injured myocardium. These results suggest that Hph1-PLCδ1 may manifest as a promising cardioprotective drug due to its inhibition of the mitochondrial apoptotic pathway in cells suffering from I/R injury.


Assuntos
Cálcio/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Fosfolipase C gama/administração & dosagem , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Injeções , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Poro de Transição de Permeabilidade Mitocondrial , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem
10.
Mediators Inflamm ; 2015: 254871, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26491223

RESUMO

Pyroptosis is the most recently identified type of regulated cell death with inflammatory response and has characteristics distinct from those of apoptosis or necrosis. Recently, independent studies have reported that small noncoding RNAs termed microRNAs (miRNAs) are involved in the regulation of pyroptosis. Nevertheless, only a handful of empirical data regarding miRNA-dependent regulation of pyroptosis is currently available. This review is aimed to provide a current update on the role of miRNAs in pyroptosis and to offer suggestions for future studies probing miRNAs as a linker connecting pyroptosis to various cardiovascular diseases (CVDs) and their potential as a therapeutic target for preventing excessive cell death of myocardium during CVDs.


Assuntos
MicroRNAs/genética , Miocárdio/citologia , Miocárdio/metabolismo , Piroptose/fisiologia , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Humanos , Piroptose/genética
11.
Proc Natl Acad Sci U S A ; 108(1): 296-301, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21173226

RESUMO

Despite the safety and feasibility of mesenchymal stem cell (MSC) therapy, an optimal cell type has not yet emerged in terms of electromechanical integration in infarcted myocardium. We found that poor to moderate survival benefits of MSC-implanted rats were caused by incomplete electromechanical integration induced by tissue heterogeneity between myocytes and engrafted MSCs in the infarcted myocardium. Here, we report the development of cardiogenic cells from rat MSCs activated by phorbol myristate acetate, a PKC activator, that exhibited high expressions of cardiac-specific markers and Ca(2+) homeostasis-related proteins and showed adrenergic receptor signaling by norepinephrine. Histological analysis showed high connexin 43 coupling, few inflammatory cells, and low fibrotic markers in myocardium implanted with these phorbol myristate acetate-activated MSCs. Infarct hearts implanted with these cells exhibited restoration of conduction velocity through decreased tissue heterogeneity and improved myocardial contractility. These findings have major implications for the development of better cell types for electromechanical integration of cell-based treatment for infarcted myocardium.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Células-Tronco Mesenquimais/metabolismo , Contração Miocárdica/fisiologia , Infarto do Miocárdio/terapia , Miócitos Cardíacos/fisiologia , Análise de Variância , Animais , Western Blotting , Conexina 43/metabolismo , Citocinas/imunologia , Eletrocardiografia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Marcação In Situ das Extremidades Cortadas , Isoproterenol/farmacologia , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/citologia , Norepinefrina/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Acetato de Tetradecanoilforbol/metabolismo
12.
Int J Mol Sci ; 15(12): 21754-76, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25431922

RESUMO

Atrial fibrillation (AF) has been recognized as a major cause of cardiovascular-related morbidity and mortality. MicroRNAs (miRNAs) represent recent additions to the collection of biomolecules involved in arrhythmogenesis. Reactive oxygen species (ROS) have been independently linked to both AF and miRNA regulation. However, no attempts have been made to investigate the possibility of a framework composed of ROS-miRNA-AF that is related to arrhythmia development. Therefore, this review was designed as an attempt to offer a new approach to understanding AF pathogenesis. The aim of this review was to find and to summarize possible connections that exist among AF, miRNAs and ROS to understand the interactions among the molecular entities underlying arrhythmia development in the hopes of finding unappreciated mechanisms of AF. These findings may lead us to innovative therapies for AF, which can be a life-threatening heart condition. A systemic literature review indicated that miRNAs associated with AF might be regulated by ROS, suggesting the possibility that miRNAs translate cellular stressors, such as ROS, into AF pathogenesis. Further studies with a more appropriate experimental design to either prove or disprove the existence of an ROS-miRNA-AF framework are strongly encouraged.


Assuntos
Fibrilação Atrial/genética , MicroRNAs/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Fibrilação Atrial/fisiopatologia , Remodelamento Atrial/genética , Humanos , MicroRNAs/genética , Modelos Biológicos
13.
Biochem Biophys Res Commun ; 435(4): 720-6, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23702479

RESUMO

A change in intracellular free calcium (Ca(2+)) is a common signaling mechanism of reperfusion-induced cardiomyocyte death. Calcium/calmodulin dependent protein kinase II (CaMKII) is a critical regulator of Ca(2+) signaling and mediates signaling pathways responsible for functions in the heart including hypertrophy, apoptosis, arrhythmia, and heart disease. MicroRNAs (miRNA) are involved in the regulation of cell response, including survival, proliferation, apoptosis, and development. However, the roles of miRNAs in Ca(2+)-mediated apoptosis of cardiomyocytes are uncertain. Here, we determined the potential role of miRNA in the regulation of CaMKII dependent apoptosis and explored its underlying mechanism. To determine the potential roles of miRNAs in H2O2-mediated Ca(2+) overload, we selected and tested 6 putative miRNAs that targeted CaMKIIδ, and showed that miR-145 represses CaMKIIδ protein expression and Ca(2+) overload. We confirmed CaMKIIδ as a direct downstream target of miR-145. Furthermore, miR-145 regulates Ca(2+)-related signals and ameliorates apoptosis. This study demonstrates that miR-145 regulates reactive oxygen species (ROS)-induced Ca(2+) overload in cardiomyocytes. Thus, miR-145 affects ROS-mediated gene regulation and cellular injury responses.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cálcio/metabolismo , Peróxido de Hidrogênio/metabolismo , MicroRNAs/farmacologia , Miócitos Cardíacos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Animais Recém-Nascidos , Células Cultivadas , Miócitos Cardíacos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
14.
Biochem Biophys Res Commun ; 423(2): 404-10, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-22664106

RESUMO

Myocardial ischemia is the major cause of morbidity and mortality due to cardiovascular diseases. This disease is a severe stress condition that causes extensive biochemical changes which trigger cardiac cell death. Stress conditions such as deprivation of glucose and oxygen activate the endoplasmic reticulum in the cytoplasm of cells, including cardiomyocytes, to generate and propagate apoptotic signals in response to these conditions. microRNAs (miRNAs) are a class of small non-coding RNAs that mediate posttranscriptional gene silencing. The miRNAs play important roles in regulating cardiac physiological and pathological events such as hypertrophy, apoptosis, and heart failure. However, the roles of miRNAs in reactive oxygen species (ROS)-mediated injury on cardiomyocytes are uncertain. In this study, we identified at the apoptotic concentration of H(2)O(2), miR-26a expression was increased. To determine the potential roles of miR-26a in H(2)O(2)-mediated cardiac apoptosis, miR-26a expression was regulated by a miR-26a or an anti-miR-26a. Overexpression of miR-26a increased apoptosis as determined by upregulation of Annexin V/PI positive cell population, caspase-3 activity and expression of pro-apoptotic signal molecules, whereas inhibition of miR-26a reduced apoptosis. We identified GSK3B as a direct downstream target of miR-26a. Furthermore, miR-26a attenuated viability and increased caspase-3 activity in normal cardiomyocytes. This study demonstrates that miR-26a promotes ROS-induced apoptosis in cardiomyocytes. Thus, miR-26a affects ROS-mediated gene regulation and cellular injury response.


Assuntos
Apoptose/genética , Regulação Enzimológica da Expressão Gênica , Quinase 3 da Glicogênio Sintase/genética , MicroRNAs/biossíntese , Miócitos Cardíacos/fisiologia , Animais , Hipóxia Celular , Células Cultivadas , Glicogênio Sintase Quinase 3 beta , MicroRNAs/genética , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Regulação para Cima
15.
Cell Biol Int ; 36(3): 305-10, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22050182

RESUMO

VSMC (vascular smooth muscle cell) proliferation contributes significantly to intimal thickening in atherosclerosis, restenosis and venous bypass graft diseases. Ang II (angiotensin II) has been implicated in VSMC proliferation though the activation of multiple growth-promoting signals. Although TZDs (thiazolidinediones) can inhibit VSMC proliferation and reduce Ang II-induced fibrosis, the mechanism underlying the inhibition of VSMC proliferation and fibrosis needs elucidation. We have used primary cultured rat aortic VSMCs and specific antibodies to investigate the inhibitory mechanism of rosiglitazone on Ang II-induced VSMC proliferation. Rosiglitazone treatment significantly inhibited Ang II-induced rat aortic VSMC proliferation in a dose-dependent manner. Western blot analysis showed that rosiglitazone significantly lowered phosphorylated ERK1/2 (extracellular-signal-regulated kinase 1/2), Akt (also known as protein kinase B), mTOR (mammalian target of rapamycin), p70S6K (70 kDa S6 kinase) and 4EBP1 (eukaryotic initiation factor 4E-binding protein) levels in Ang II-treated VSMCs. In addition, PPAR-γ (peroxisome-proliferator-activated receptor γ) mRNA increased significantly and CTGF (connective tissue growth factor), Fn (fibronectin) and Col III (collagen III) levels decreased significantly. The results demonstrate that the rosiglitazone directly inhibits the pro-atherosclerotic effect of Ang II on rat aortic VSMCs. It also attenuates Ang II-induced ECM (extracellular matrix) molecules and CTGF production in rat aortic VSMCs, reducing fibrosis. Importantly, PPAR-γ activation mediates these effects, in part, through the mTOR-p70S6K and -4EBP1 system.


Assuntos
Angiotensina II/metabolismo , Proliferação de Células , Músculo Liso Vascular/citologia , Serina-Treonina Quinases TOR/metabolismo , Tiazolidinedionas/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Ratos , Rosiglitazona , Transdução de Sinais/efeitos dos fármacos
16.
Mol Biol Rep ; 39(10): 9549-56, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22733491

RESUMO

Pathological stress including myocardial infarction and hypertension causes a negative effect on calcium regulation and homeostasis. Nevertheless, few studies reveal that Ca(2+) regulatory genes are related to pathological status in cardiomyocytes under early hypoxia. To determine the alteration of Ca(2+)-related gene in hypoxic myocytes, primary neonatal rat ventricular cardiomyocytes (NRVCMs) was isolated. Survival of hypoxic NRVCMs was significantly decreased in 6 h. We confirmed an increase of reactive oxygen species (ROS) generation and Ca(2+) overload in hypoxic NRVCMs by using 2',7'-dichlorodihydro-fluorescein diacetate (H2DCFDA) and FACS analysis. Furthermore, survival/apoptotic signals were also regulated in same condition. The expression profiles of more than 30,000 genes from NRVCMs that were subjected to early hypoxia revealed 630 genes that were differentially regulated. The intracellular Na(+) overload and Ca(2+) handling genes with at least two-fold changes were confirmed. The levels of Ca(2+)-handling proteins (calsequestrin, calmodulin, and calreticulin), ion channels (NCX, Na(+)-K(+)-ATPase, SERCA2a, and PLB), and stress markers (RyR2, ANP, and BNP) were significantly altered in early hypoxia. These results demonstrate that early hypoxia alters Ca(2+)-related gene expression in NRVCMs, leading to pathological status.


Assuntos
Regulação da Expressão Gênica , Família Multigênica , Miócitos Cardíacos/metabolismo , Transcriptoma , Animais , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Hipóxia Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Análise por Conglomerados , Canais Iônicos/genética , Canais Iônicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Ratos , Ratos Sprague-Dawley
17.
J Recept Signal Transduct Res ; 31(1): 66-74, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21067463

RESUMO

The role of tissue transglutaminase 2 (TG2) in cardiac myocyte apoptosis under oxidative stress induced by ischemic injury remains unclear. Here, we investigated the effects of TG2 on apoptosis of cardiomyocytes under oxidative stress. Ectopic expression of TG2 increased caspase-3 activity and calcium overload in cardiomyocytes. Expression levels of TG2 were significantly increased in H(2)O(2)-treated cardiomyocytes. Caspase-3 activity assay demonstrated its considerable correlation with TG2 expression, which supported that caspase-3 inhibitor inhibited the apoptosis induced by the ectopic overexpression of TG2. In addition, the other apoptotic signals, such as caspase-8, cytochrome c, and Bax, were increased dependent with TG2 expression in H(2)O(2)-treated cardiomyocytes. These results indicated that apoptotic signals had a positive correlation with TG2 expression. The decreased expression of phospholipase C (PLC)-δ1 and phospho-PKC in H(2)O(2)-treated cardiomyocytes were rescued by TG2 silencing. Together, our data strongly suggest that oxidative stress up-regulates TG2 expression in cardiomyocytes, leading to apoptosis.


Assuntos
Apoptose , Proteínas de Ligação ao GTP/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/enzimologia , Estresse Oxidativo , Transglutaminases/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteína 2 Glutamina gama-Glutamiltransferase , Ratos , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
18.
Stem Cells ; 28(3): 555-63, 2010 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-20073042

RESUMO

The integrity of transplanted mesenchymal stem cells (MSCs) for cardiac regeneration is dependent on cell-cell or cell-matrix adhesion, which is inhibited by reactive oxygen species (ROS) generated in ischemic surroundings after myocardial infarction. Intracellular ROS play a key role in the regulation of cell adhesion, migration, and proliferation. This study was designed to investigate the role of ROS on MSC adhesion. In H(2)O(2) treated MSCs, adhesion and spreading were inhibited and detachment was increased in a dose-dependent manner, and these effects were significantly rescued by co-treatment with the free radical scavenger, N-acetyl-L-cysteine (NAC, 1 mM). A similar pattern was observed on plates coated with different matrices such as fibronectin and cardiogel. Hydrogen peroxide treatment resulted in a marked decrease in the level of focal adhesion-related molecules, such as phospho-FAK and p-Src in MSCs. We also observed a significant decrease in the integrin-related adhesion molecules, alpha V and beta1, in H(2)O(2) treated MSCs. When injected into infarcted hearts, the adhesion of MSCs co-injected with NAC to the border region was significantly improved. Consequently, we observed that fibrosis and infarct size were reduced in MSC and NAC-injected rat hearts compared to in MSC-only injected hearts. These results indicate that ROS inhibit cellular adhesion of engrafted MSCs and provide evidence that the elimination of ROS might be a novel strategy for improving the survival of engrafted MSCs.


Assuntos
Moléculas de Adesão Celular/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/cirurgia , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Moléculas de Adesão Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Quinase 1 de Adesão Focal/efeitos dos fármacos , Quinase 1 de Adesão Focal/metabolismo , Adesões Focais/efeitos dos fármacos , Adesões Focais/metabolismo , Sequestradores de Radicais Livres/farmacologia , Técnicas de Introdução de Genes , Sobrevivência de Enxerto/fisiologia , Peróxido de Hidrogênio/farmacologia , Integrinas/efeitos dos fármacos , Integrinas/metabolismo , Masculino , Isquemia Miocárdica/fisiopatologia , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley , Regeneração/fisiologia , Quinases da Família src/efeitos dos fármacos , Quinases da Família src/metabolismo
19.
Biochem Biophys Res Commun ; 402(2): 272-9, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-20937252

RESUMO

The efficacy of mesenchymal stem cell (MSC) therapy for myocardial regeneration is limited by the poor survival of stem cells after transplantation into the infarcted heart. To improve the cell survival of MSCs in the infarcted heart, MSCs were genetically engineered to overexpress phosphoinositide-3-kinase class II alpha (PI3K-C2α). PI3K-C2α overexpression increased PI3K expression and the cell viability of MSCs. Furthermore, levels of survival-related phosphorylation were elevated in PI3K-C2α-MSCs. But, the level of apoptotic proteins downregulated and the number of PI-positive cells decreased in PI3K-C2α-MSCs compared to hypoxic MSCs. Nine rats per group had 1×10(6) cells (20 µl PBS) transplanted after myocardial infarction. One week after transplantation, infarct size and area of fibrosis were reduced in the PI3K-C2α-MSC-transplanted group. The number of TUNEL positive cells declined, while the mean microvessel count per field was higher in the PI3K-C2α-MSC group than the MSC-injected group. Heart function was improved in the PI3K-C2α-MSCs group as assessed using a Millar catheter at 3weeks after transplantation. These findings suggest that overexpression of PI3K-C2α in MSCs can assist cell survival and enhance myocardial regeneration.


Assuntos
Classe II de Fosfatidilinositol 3-Quinases/genética , Coração/fisiologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/enzimologia , Infarto do Miocárdio/terapia , Miocárdio/enzimologia , Regeneração/genética , Animais , Apoptose/genética , Sobrevivência Celular/genética , Engenharia Genética , Masculino , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Ratos , Ratos Sprague-Dawley
20.
Stem Cells ; 27(6): 1358-65, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19489098

RESUMO

Mesenchymal stem cells (MSCs) therapy has limitations due to the poor viability of MSCs after cell transplantation. Integrin-mediated adhesion is a prerequisite for cell survival. As a novel anti-death strategy to improve cell survival in the infarcted heart, MSCs were genetically modified to overexpress integrin-linked kinase (ILK). The survival rate of ILK-transfected MSCs (ILK-MSCs) was augmented by about 1.5-fold and the phosphorylation of ERK1/2 and Akt in ILK-MSCs were increased by about three and twofold, respectively. ILK-MSCs demonstrated an increase of twofold in the ratio of Bcl-2/Bax and inhibited caspase-3 activation, compared with hypoxic MSCs. The adhesion rate of ILK-MSCs also had a 32.2% increase on the cardiac fibroblast-derived three-dimensional matrix and ILK-MSCs showed higher retention by about fourfold compared to unmodified MSCs. Six animals per group were used for the in vivo experiments analyzed at 1 week after occlusion of the left coronary artery. ILK-MSC transplanted rats had a 12.0% +/- 3.1% smaller infarct size than MSC-treated rats after ligation of left anterior descending coronary artery. Transplantation of ILK-MSCs not only led to a 16.0% +/- 0.4% decrease in the fibrotic heart area, but also significantly reduced the apoptotic positive index by two-thirds when compared with ligation only. The mean microvessel count per field in the infarcted myocardium of ILK-MSCs group was increased relative to the sham group and MSCs group. In conclusion, the ILK gene transduction of MSCs further assisted cell survival and adhesion, and improved myocardial damage when compared with MSC only after transplantation.


Assuntos
Hipóxia Celular/genética , Sobrevivência de Enxerto/genética , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Isquemia Miocárdica/terapia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Apoptose/fisiologia , Western Blotting , Adesão Celular/genética , Marcação In Situ das Extremidades Cortadas , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Isquemia Miocárdica/patologia , Engenharia de Proteínas , Proteínas Serina-Treonina Quinases/genética , Ratos , Ratos Sprague-Dawley , Transdução Genética
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