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Induced pluripotent stem cells (iPSCs) are obtained by introducing exogenous genes or adding chemicals to the culture medium to induce somatic cell differentiation. Similarly to embryonic stem cells, iPSCs have the ability to differentiate into all three embryonic cell lines. iPSCs can differentiate into cardiac muscle cells through two-dimensional differentiation methods such as monolayer cell culture and co-culture, or through embryoid body and scaffold-based three-dimensional differentiation methods. In addition, the process of iPSCs differentiation into cardiac muscle cells also requires activation or inhibition of specific signaling pathways,such as Wnt, BMP, Notch signaling pathways to mimic the development of the heart in vivo. In recent years, suspension culturing in bioreactors has been shown to produce large number of iPSCs derived cardiac muscle cells (iPSC-CMs). Before transplantation, it is necessary to purify iPSC-CMs through metabolic regulation or cell sorting to eliminate undifferentiated iPSCs, which may lead to teratoma formation. The transplantation methods for iPSC-CMs are mainly injection of cell suspension and transplantation of cell patches into the infarcted myocardium. Animal studies have shown that transplantation of iPSC-CMs into the infarcted myocardium can improve cardiac function. This article reviews the progress in preclinical studies on iPSC-CMs therapy for acute myocardial infarction and discusses the limitations and challenges of its clinical application to provide references for further clinical research and application.
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Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Infarto do Miocárdio , Células-Tronco Pluripotentes Induzidas/citologia , Infarto do Miocárdio/terapia , Humanos , Animais , Miócitos Cardíacos/citologia , Transplante de Células-Tronco/métodosRESUMO
Maduramicin (Mad), a polyether ionophore antibiotic, has been reported to be toxic to animals and humans because of being used at high doses or for long time, resulting in heart failure. However, the toxic mechanism of Mad in cardiac muscle cells is not well understood. Here, we show that Mad induced cell viability reduction and apoptosis in cardiac-derived H9c2, HL-1 cells, primary cardiomyocytes, and murine cardiac muscles, which was because of the inhibition of extracellular-signal-regulated kinase 1/2 (Erk1/2). Expression of constitutively active mitogen-activated protein kinase kinase 1 (MKK1) attenuated Mad-induced cell death in H9c2 cells, whereas silencing Erk1/2 or ectopic expression of dominant negative MKK1 strengthened Mad-induced cell death. Moreover, we found that both phosphatase and tensin homolog on chromosome 10 (PTEN) and protein kinase B (Akt) were implicated in the regulation of Erk1/2 inactivation and apoptosis in the cells and tissues exposed to Mad. Overexpression of dominant negative PTEN and/or constitutively active Akt, or constitutively active Akt and/or constitutively active MKK1 rescued the cells from Mad-induced dephosphorylated-Erk1/2 and cell death. Furthermore, Mad-induced reactive oxygen species (ROS) activated PTEN and inactivated Akt-Erk1/2 contributing to cell death, as N-acetyl- L-cysteine ameliorated the event. Taken together, the results disclose that Mad inhibits Erk1/2 via ROS-dependent activation of PTEN and inactivation of Akt, leading to cell death in cardiac muscle cells. Our findings suggest that manipulation of the ROS-PTEN-Akt-Erk1/2 pathway may be a potential approach to prevent Mad-induced cardiotoxicity.
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Antibacterianos/efeitos adversos , Lactonas/efeitos adversos , Sistema de Sinalização das MAP Quinases/fisiologia , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Humanos , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , PTEN Fosfo-Hidrolase/genética , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Espécies Reativas de OxigênioRESUMO
We have previously demonstrated that the neural stem-cell marker nestin is expressed in hair-follicle stem cells located in the bulge area which are termed hair-follicle-associated pluripotent (HAP) stem cells. HAP stem cells from mouse and human could form spheres in culture, termed hair spheres, which are keratin 15-negative and nestin-positive and could differentiate to neurons, glia, keratinocytes, smooth muscle cells, and melanocytes in vitro. Subsequently, we demonstrated that nestin-expressing stem cells could effect nerve and spinal cord regeneration in mouse models. Recently, we demonstrated that HAP stem cells differentiated to beating cardiac muscle cells. We recently observed that isoproterenol directs HAP stem cells to differentiate to cardiac-muscle cells in large numbers in culture compared to HAP stem cells not supplemented with isoproterenol. The addition of activin A, bone morphogenetic protein 4, and basic fibroblast growth factor, along with isoproternal, induced the cardiac muscle cells to form tissue sheets of beating heart muscle cells. In the present study, we report that, under hypoxic conditions, HAP stem cells differentiated to troponin-positive cardiac-muscle cells at a higher rate that under normoxic conditions. Hypoxia did not influence the differentiation to other cell types. For future use of HAP stem cells for cardiac muscle regeneration, hypoxia should enhance the rate of differentiation thereby providing patients more opportunities to use their own HAP stem cells which are easily accessible, for this purpose. J. Cell. Biochem. 118: 554-558, 2017. © 2016 Wiley Periodicals, Inc.
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Diferenciação Celular , Folículo Piloso/metabolismo , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes/metabolismo , Animais , Hipóxia Celular , Folículo Piloso/citologia , Camundongos , Miócitos Cardíacos/citologia , Células-Tronco Pluripotentes/citologiaRESUMO
Alternative splicing is one of the major cellular processes that determine the tissue-specific expression of protein variants. However, it remains challenging to identify physiologically relevant and tissue-selective proteins that are generated by alternative splicing. Hence, we investigated the target spectrum of the splicing factor Rbfox1 in the cardiac muscle context in more detail. By using a combination of in silico target prediction and in-cell validation, we identified several focal adhesion proteins as alternative splicing targets of Rbfox1. We focused on the alternative splicing patterns of vinculin (metavinculin isoform) and paxillin (extended paxillin isoform) and identified both as potential Rbfox1 targets. Minigene analyses suggested that both isoforms are promoted by Rbfox1 due to binding in the introns. Focal adhesions play an important role in the cardiac muscle context, since they mainly influence cell shape, cytoskeletal organization, and cell-matrix association. Our data confirmed that depletion of Rbfox1 changed cardiomyoblast morphology, cytoskeletal organization, and multinuclearity after differentiation, which might be due to changes in alternative splicing of focal adhesion proteins. Hence, our results indicate that Rbfox1 promotes alternative splicing of focal adhesion genes in cardiac muscle cells, which might contribute to heart disease progression, where downregulation of Rbfox1 is frequently observed.
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Processamento Alternativo , Adesões Focais , Miócitos Cardíacos , Paxilina , Fatores de Processamento de RNA , Processamento Alternativo/genética , Fatores de Processamento de RNA/metabolismo , Fatores de Processamento de RNA/genética , Adesões Focais/metabolismo , Adesões Focais/genética , Animais , Paxilina/metabolismo , Paxilina/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/citologia , Camundongos , Vinculina/metabolismo , Vinculina/genética , Humanos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/genéticaRESUMO
BACKGROUND: Cardiomyocyte size histomorphometry is widely required in myocardial remodeling research, but it relies on subjective, time-consuming manual tracing. We aimed to present the CmyoSize, a Fiji/ImageJ macro that reproducibly measures the transnuclear cross-sectional size of cardiomyocytes in multiple H&E images. METHODS: CmyoSize output per image are: mean cross-sectional area (CSA), CSA's local standard deviation (LSD), mean width, and width's LSD. CmyoSize was validated against measurements of an expert examiner, using myocardium micrographs (400-fold magnification) from rats treated with hyperbaric oxygen (HBO), streptozotocin (STZ), as well as control rats (five images/heart, five rats/group). RESULTS: CmyoSize achieved high cardiomyocyte detection precision (95.17 ± 1.11%) and it analyzed each image at least 30-times faster than expert examiner (8.44 ± 0.17 s vs. 266.70 ± 25.15 s). Bland-Altman analyses showed no meaningful bias ( ± 95% confidence interval) between both methods: mean CSA = 1.88 ± 6.83 µm2, CSA's LSD = -4.55 ± 5.07 µm2; mean width = -0.02 ± 0.22 µm; width's LSD = -0.16 ± 0.17 µm. Pearson's r ranged from 0.85 to 0.94 (P < 0.0001). CmyoSize revealed homogenous cardiomyocyte hypertrophy in HBO-treated animals and STZ-induced heterogeneous hypertrophy. CONCLUSION: Fully automated, standardized cardiomyocyte size quantification in H&E images using CmyoSize is feasible, accurate, and time-efficient.
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Miocárdio , Miócitos Cardíacos , Animais , Microscopia , Miocárdio/patologia , Oxigênio , Ratos , Coloração e RotulagemRESUMO
Serelaxin (RLX) designates the pharmaceutical form of the human natural hormone relaxin-2 that has been shown to markedly reduce tissue and cell damage induced by hypoxia and reoxygenation (HR). The evidence that RLX exerts similar protective effects on different organs and cells at relatively low, nanomolar concentrations suggests that it specifically targets a common pathogenic mechanism of HR-induced damage, namely oxidative stress. In this study we offer experimental evidence that RLX (17 nmol L-1), added to the medium of HR-exposed H9c2 rat cardiac muscle cells, significantly reduces cell oxidative damage, mitochondrial dysfunction and apoptosis. These effects appear to rely on the up-regulation of the cellular availability of reduced glutathione (GSH), a ubiquitous endogenous antioxidant metabolite. Conversely, superoxide dismutase activity was not influenced by RLX, which, however, was not endowed with chemical antioxidant properties. Taken together, these findings verify the major pharmacological role of RLX in the protection against HR-induced oxidative stress, and shed first light on its mechanisms of action.
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BACKGROUND: The shRNA lentiviral vector was constructed to silence c-Ski expression in cardiac mus- cle cells, with the aim of exploring the role of c-Ski in transforming growth factor b1 (TGF-b1)-induced epithelial-mesenchymal transitions (EMT) in H9C2 cells. METHODS: Real-time polymerase chain reaction (RT-PCR) and western blot were used to detect c-Ski ex- pression at protein and messenger ribonucleic acid (mRNA) levels in 5 different cell lines. Then, lentiviral vector was constructed to silence or overexpress c-Ski in H9C2 cells. MTT and/or soft agar assay and tran- swell assay were used to detect cell proliferation and migration, respectively. The expression levels of c-Ski under different concentrations of TGF-b1 stimulation were detected by RT-qPCR and immunocytochemi- cal analysis. In the presence or absence of TGF-b1 stimulation, the proteins' expression levels of a-SMA, FN and E-cadherin, which are closely correlated with the process of EMT, were measured by western blot after c-Ski silencing or overexpression. Meanwhile, the effect of c-Ski on Samd3 phosphorylation with TGF-b1 stimulation was investigated. RESULTS: There is a high expression of c-Ski at protein and mRNA levels in H9C2 cell line, which first demonstrated the presence of c-Ski expression in H9C2 cells. Overexpression of c-Ski significantly increased H9C2 cell proliferation. The ability of c-Ski gene silencing to suppress cell proliferation was gradually enhanced, and inhibition efficiency was the highest after 6 to 7 d of transfection. Moreover, H9C2 cells with c-Ski knockdown gained significantly aggressive invasive potential when compared with the control group. TGF-b1 stimulation could dose-independently reduce c-Ski expression in H9C2 cells and lead to obvious down-regulated expression of E-cadherin. Interestingly, c-Ski could restore E-cadherin expression while suppressing a-SMA and/or FN expression stimulated by TGF-b1. How- ever, shRNA-induced c-Ski knockdown aggravated only the TGF-b1-induced EMT. Moreover, c-Ski- -shRNA also promoted the phosphorylation of Samd3 induced by TGF-b1. CONCLUSIONS: c-Ski expression in cardiac muscle cells could be down-regulated by TGF-b1. Silencing of c-Ski gene was accompanied by down-regulation of E-cadherin, up-regulation of a-SMA and/or FN and Smad3 phosphorylation induced by TGF-b1, promoting EMT process. Therefore, c-Ski may be closely associated with TGF-b1-induced EMT and play an important role in cardiac fibrosis develop- ment and progression.
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Cardiomiopatias/genética , Proteínas de Ligação a DNA/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação da Expressão Gênica , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas/genética , RNA/genética , Fator de Crescimento Transformador beta1/metabolismo , Western Blotting , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Linhagem Celular , Proliferação de Células , Proteínas de Ligação a DNA/biossíntese , Fibrose/genética , Fibrose/metabolismo , Fibrose/patologia , Inativação Gênica , Humanos , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas/biossíntese , Transdução de SinaisRESUMO
Our previous studies showed that nestin-expressing hair follicle-associated-pluripotent (HAP) stem cells, which reside in the bulge area of the hair follicle, could restore injured nerve and spinal cord and differentiate into cardiac muscle cells. Here we transplanted mouse green fluorescent protein (GFP)-expressing HAP stem-cell colonies enclosed on polyvinylidene fluoride membranes (PFM) into the severed thoracic spinal cord of nude mice. After seven weeks of implantation, we found the differentiation of HAP stem cells into neurons and glial cells. Our results also showed that PFM-captured GFP-expressing HAP stem-cell colonies assisted complete reattachment of the thoracic spinal cord. Furthermore, our quantitative motor function analysis with the Basso Mouse Scale for Locomotion (BMS) score demonstrated a significant improvement in the implanted mice compared to non-implanted mice with a severed spinal cord. Our study also showed that it is easy to obtain HAP stem cells, they do not develop teratomas, and do not loose differentiation ability when cryopreserved. Collectively our results suggest that HAP stem cells could be a better source compared to induced pluripotent stem cells (iPS) or embryonic stem (ES) cells for regenerative medicine, specifically for spinal cord repair.
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Folículo Piloso/citologia , Membranas Artificiais , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/transplante , Polivinil/farmacologia , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Animais , Diferenciação Celular/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Células-Tronco Pluripotentes/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/patologiaRESUMO
We have previously demonstrated that the nestin-expressing cells from the upper part of the hair follicle can differentiate to neurons and other cell types. We have termed these cells as hair-associated-pluripotent (HAP) stem cells. In the present chapter, we describe methods for HAP stem cells to differentiate to beating cardiac muscle cells. The mouse vibrissa hair follicle was divided into three parts (upper, middle, and lower), and each part was suspended separately in DMEM containing 10 % fetal bovine serum (FBS). All three parts of hair follicle differentiate to neurons, glial cells, keratinocytes, smooth muscle cells, and cardiac muscle cells. The differentiation potential to cardiac muscle is greatest in the upper part of the follicle. Hair spheres comprised of HAP stem cells formed from the upper part of vibrissa hair follicle can differentiate to cardiac muscle cells.
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Diferenciação Celular , Folículo Piloso/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Células-Tronco Pluripotentes/citologia , Animais , Biomarcadores , Imunofluorescência , Imunofenotipagem , Camundongos , Células-Tronco Pluripotentes/metabolismo , VibrissasRESUMO
We have previously discovered nestin-expressing hair-follicle-associated pluripotent (HAP) stem cells and have shown that they can differentiate to neurons, glia, and many other cell types. HAP stem cells can be used for nerve and spinal cord repair. We have recently shown the HAP stem cells can differentiate to beating heart-muscle cells and tissue sheets of beating heart-muscle cells. In the present study, we determined the efficiency of HAP stem cells from mouse vibrissa hair follicles of various ages to differentiate to beating heart-muscle cells. We observed that the whiskers located near the ear were more efficient to differentiate to cardiac-muscle cells compared to whiskers located near the nose. Differentiation to cardiac-muscle cells from HAP stem cells in cultured whiskers in 4-week-old mice was significantly greater than in 10-, 20-, and 40-week-old mice. There was a strong decrease in differentiation potential of HAP stem cells to cardiac-muscle cells by 10 weeks of age. In contrast, the differentiation potential of HAP stem cells to other cell types did not decrease with age. The possibility of rejuvenation of HAP stem cells to differentiate at high efficiency to cardiac-muscle cells is discussed.
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Envelhecimento/fisiologia , Diferenciação Celular , Folículo Piloso/citologia , Miócitos Cardíacos/citologia , Células-Tronco Pluripotentes/citologia , Animais , Biomarcadores/metabolismo , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Vibrissas/citologiaRESUMO
Nestin-expressing stem cells of the hair follicle, discovered by our laboratory, have been shown to be able to form outer-root sheaths of the follicle as well as neurons and many other non-follicle cell types. We have termed the nestin-expressing stem cells of the hair follicle as hair-follicle-associated pluripotent (HAP) stem cells. We have shown that the HAP stem cells from the hair follicle can effect the repair of peripheral nerve and spinal cord injury. The hair follicle stem cells differentiate into neuronal and glial cells after transplantation to the injured peripheral nerve and spinal cord, and enhance injury repair and locomotor recovery. When the excised hair follicle with its nerve stump was placed in Gelfoam(®) 3D histoculture, HAP stem cells grew and extended the hair follicle nerve which consisted of ßIII-tubulin-positive fibers with F-actin expression at the tip. These findings indicate that ßIII-tubulin-positive fibers elongating from the whisker follicle sensory nerve stump were growing axons. The growing whisker sensory nerve was highly enriched in HAP stem cells, which appeared to play a major role in its elongation and interaction with other nerves in 3D Gelfoam(®) histoculture, including the sciatic nerve, the trigeminal nerve, and the trigeminal nerve ganglion. These results suggest that a major function of the HAP stem cells in the hair follicle is for growth of the follicle sensory nerve. Recently, we have shown that HAP stem cells can differentiate into beating cardiac muscle cells. HAP stem cells have critical advantages for regenerative medicine over embryonic stem (ES) cells and induced pluripotent stem (iPS) cells in that they are highly accessible from each patient, thereby eliminating immunological issues since they are autologous, require no genetic manipulation, are non-tumorigenic, and do not present ethical issues.
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Folículo Piloso/citologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Animais , Biomarcadores , Diferenciação Celular , Movimento Celular , Humanos , Camundongos , Neurônios Motores/citologia , Neurônios Motores/metabolismo , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Traumatismos dos Nervos Periféricos/terapia , Traumatismos da Medula Espinal/terapiaRESUMO
We have previously demonstrated that the neural stem-cell marker nestin is expressed in hair follicle stem cells located in the bulge area which are termed hair-follicle-associated pluripotent (HAP) stem cells. HAP stem cells from mouse and human could form spheres in culture, termed hair spheres, which are keratin 15-negative and CD34-positive and could differentiate to neurons, glia, keratinocytes, smooth muscle cells, and melanocytes in vitro. Subsequently, we demonstrated that nestin-expressing stem cells could effect nerve and spinal cord regeneration in mouse models. In the present study, we demonstrated that HAP stem cells differentiated to beating cardiac muscle cells. We separated the mouse vibrissa hair follicle into 3 parts (upper, middle, and lower), and suspended each part separately in DMEM containing 10% FBS. All three parts of hair follicle differentiated to beating cardiac muscle cells as well as neurons, glial cells, keratinocytes and smooth muscle cells. The differentiation potential to cardiac muscle is greatest in the upper part of the follicle. The beat rate of the cardiac muscle cells was stimulated by isoproterenol and inhibited by propanolol. HAP stem cells have potential for regenerative medicine for heart disease as well as nerve and spinal cord repair.
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Folículo Piloso/citologia , Miócitos Cardíacos/metabolismo , Nestina/metabolismo , Células-Tronco Pluripotentes/metabolismo , Animais , Antígenos CD34/metabolismo , Diferenciação Celular/efeitos dos fármacos , Humanos , Isoproterenol/farmacologia , Queratina-15/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Modelos Animais , Miócitos Cardíacos/citologia , Neurônios/fisiologia , Células-Tronco Pluripotentes/citologia , Regeneração , Regeneração da Medula Espinal/fisiologiaRESUMO
Reperfusion injury after oxygen starvation is a key pathogenic step in ischemic diseases. It mainly consists in oxidative stress, related to mitochondrial derangement and enhanced generation of reactive oxygen species (ROS), mainly superoxide anion (O2(â¢2)), and peroxynitrite by cells exposed to hypoxia. This in vitro study evaluates whether Mn(II)(4,10-dimethyl-1,4,7,10-tetraazacyclododecane-1,7-diacetate).2H2O, or Mn(II)(Me2DO2A), a new low molecular weight, Mn(II)-containing O2(â¢) scavenger, has a direct protective action on H9c2 rat cardiac muscle cells subjected to hypoxia and reoxygenation. Mn(II)(Me2DO2A) (1 and 10 µmol/l) was added to the culture medium at reoxygenation and maintained for 2 h. In parallel experiments, the inactive congener Zn(II)(Me2DO2A), in which Zn(II) replaced the functional Mn(II) center in the same organic scaffold, was used as negative control. Mn(II)(Me2DO2A) (10 µmol/l) significantly increased cardiac muscle cell viability (trypan blue assay), improved mitochondrial activity (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide test, membrane potential Δψ), reduced apoptosis (mitochondrial permeability transition pore opening, caspase-3, terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling assay), decreased intracellular ROS levels (2',7'-dichlorodihydrofluorescein diacetate and MitoSOX assays), and decreased protein nitroxidation (nitrotyrosine [NT] expression) and DNA oxidation (8-hydroxy-deoxyguanosine levels). Of note, Zn(II)(Me2DO2A) had no protective effect. The mechanism of Mn(II)(Me2DO2A) relies on concentration-dependent removal of harmful O2(â¢) generated at reoxygenation from dysfunctional mitochondria in hypoxia-induced cells, as indicated by the MitoSOX assay. This study suggests that Mn(II)(Me2DO2A) is a promising antioxidant drug capable of reducing O2(â¢)-mediated cell oxidative stress which occurs at reoxygenation after hypoxia. In perspective, Mn(II)(Me2DO2A) might be used to reduce ischemia-reperfusion organ damage in acute vascular diseases, as well as to extend the viability of explanted organs before transplantation.
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Complexos de Coordenação/farmacologia , Sequestradores de Radicais Livres/farmacologia , Manganês/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Superóxidos/metabolismo , Animais , Antioxidantes/farmacologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Linhagem Celular , Peso Molecular , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
Myocardial infarction (MI; "heart attack") can cause injury to or death of heart muscle tissue (myocardium) owing to prolonged ischemia and hypoxia. Troponins and CK-MB are released from heart muscle cells during MI. It has been demonstrated that energy expenditure is regulated by adropin expressed in the endocardium, myocardium, and epicardium. We hypothesized that adropin is released into the bloodstream during myocardial muscle injury caused by MI, so the serum level rises as myocytes die. Therefore, we examined the association between adropin expression and myocardial infarction in isoproterenol-induced myocardial infarction. Rats were randomly allocated to six groups. After treatment they were decapitated and their blood and tissues were collected for adropin measurement. Changes in adropin synthesis in rat heart, kidney and liver tissues in isoproterenol (ISO)-induced MI were demonstrated immunohistochemically. Serum adropin concentrations were measured by ELISA, and troponin-I, CK and CK-MB concentrations by autoanalysis. The results demonstrated that cardiac muscle cells, glomerular, peritubular and renal cortical interstitial cells, hepatocytes and liver sinusoidal cells all synthesize adropin, and synthesis increased 1-24 h after MI except in the liver cells. The findings elucidate the pathogenesis of MI, and the gradual increase in serum adropin could be a novel diagnostic marker and serve as an alternative to troponin-I measurement for diagnosing MI.
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Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Peptídeos/sangue , Troponina I/sangue , Agonistas Adrenérgicos beta/efeitos adversos , Agonistas Adrenérgicos beta/farmacologia , Animais , Biomarcadores/sangue , Proteínas Sanguíneas , Isoproterenol/efeitos adversos , Isoproterenol/farmacologia , Infarto do Miocárdio/induzido quimicamente , Especificidade de Órgãos , RatosRESUMO
The relatively recent development of microfluidic systems with wide-ranging capabilities for generating realistic 2D or 3D systems with single or multiple cell types has given rise to an extensive collection of platform technologies useful in muscle tissue engineering. These new systems are aimed at (i) gaining fundamental understanding of muscle function, (ii) creating functional muscle constructs in vitro, and (iii) utilizing these constructs a variety of applications. Use of microfluidics to control the various stimuli that promote differentiation of multipotent cells into cardiac or skeletal muscle is first discussed. Next, systems that incorporate muscle cells to produce either 2D sheets or 3D tissues of contractile muscle are described with an emphasis on the more recent 3D platforms. These systems are useful for fundamental studies of muscle biology and can also be incorporated into drug screening assays. Applications are discussed for muscle actuators in the context of microrobotics and in miniaturized biological pumps. Finally, an important area of recent study involves coculture with cell types that either activate muscle or facilitate its function. Limitations of current designs and the potential for improving functionality for a wider range of applications is also discussed, with a look toward using current understanding and capabilities to design systems of greater realism, complexity and functionality.
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Técnicas Analíticas Microfluídicas/instrumentação , Células Musculares/citologia , Células Musculares/fisiologia , Desenvolvimento Muscular/fisiologia , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Animais , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , MiniaturizaçãoRESUMO
Summary: In this study we tried to investigate the effect of fructose-1,6-diphosphate and HTK solution on protecting primary cardiac muscle cells of rat with cold preservation. The primary cardiac muscle cells of rat were cultured in vitro with four preservation solutions respectively: 0.9 % sodium chloride solution (group A), FDP (group B), HTK solution (group C) and a mixture of FDP and HTK solution (group D). The cells were preserved for 6, 8 and 10 h at 0-4 ℃. The values of AST and LDH-L and the Na+-K+ ATPase activity in cardiac muscle cells were detected, and the survival rate of cardiac muscle cells was detected with trypan blue staining. The values of AST and LDH-L in group C and group D were remarkable lower those in group A and group B (P<0.001), while the Na+-K+ ATPase activity and the survival rate of cells in group C and group D were much higher than those in group A and group B (P<0.001). The values of AST and LDH-L after 6 hours in group D decreased much more than those in group C (P<0.01), while the Na+-K+ ATPase activity and the survival rate of cells in group D improved more than those in group C (P<0.01). Both of the HTK solution and the mixture of HTK and FDP solution have an evident effect on protecting the primary cardiac muscle cells of rat in vitro with cold preservation, Compared with the HTK solution, the mixture solution has a better short-term protective effect.
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20m, hypertrophy of nuclei, dilatation of T tubules, mutiple intercalated discs and increase of mitochondria and myofibrils. But the atrial cardiac muscle cells with degeneration showed myofibrillar lysis, abnormal Z bands, mitochondrial swelling and extramembranous disruption, sarcoplasmic reticulum proliferation and dilatation,myelin figures formation and interstitial fibrosis These results suggested that the degree of hypertropy and degeneration of atrial cardiac muscle cells was related to the types, injuried size of congenital heart disease and the age, cardiac functional state of patients
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@# The apoptosis of cardiac muscle cells refers to an initiative cell death process that is controlled by a series of genes, and in fact it is a kind of physiological cell death. The authors of this article reviewed and analyzed the biology characteristics and development mechanisms of the apoptosis of cardiac muscle cells, summarized the research progress of the apoptosis of cardiac muscle cells and exercise, so as to offer theoretical reference for exercise training and heart protecting.