Name: a doxorubicin-induced murine model of dilated cardiomyopathy in vivo
Uploaded: 2020-05-16T14:00:00.000+00:00
Duration: 5 min 14 s
Description: Watch this Scientific Journal Video about A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo at JoVE.com

Este trabajo fue apoyado por Key Project Medical Science and Technology Development Foundation, Nanjing Department of Health (No.YKK16098).

Los experimentos con animales fueron aprobados por el Comité Institucional de Cuidado y Uso de Animales (IACUC) del Hospital Nanjing Drum Tower.
1. Preparación de los reactivos y animales
<ol><li>Disolver el clorhidrato de doxorrubicina (Pfizer, EE.UU.) en agua esterilizada. Vórtice para obtener una solución Dox de 1 mg/ml y mantener a 4 °C.</li>
	<li>Use ratones C57BL/6 (8–10 semanas de edad; 25–30 g de peso). Para este estudio, los ratones fueron comprados en el Centro de Investigación de Animales Modelo de la Universidad de Nanjing y mantenidos en la sala de animales del Hospital nanjing Drum Tower.</li>
	<li>Las jaulas de ratones libres de patógenos se mantuvieron bajo un ciclo de luz/oscuridad de 12 h a una temperatura constante de 23 °C. Todos los animales fueron alimentados con una dieta normal de chow y recibieron comida y agua ad libitum.</li>
</ol>2. Establecimiento del modelo animal DCM
<ol><li>Aleatorizar ratones en un grupo normal (n = 5) y Dox (n = 5).</li>
	<li>Administrar la solución dox por vía intraperitoneal a una dosis de 5 mg/kg utilizando una jeringa esterilizada de 1 ml 1 veces a la semana para el grupo Dox. Trate a los ratones de control de la misma manera con la misma cantidad de solución salina.</li>
	<li>Mida el peso corporal de los dos grupos semanalmente. En consecuencia, ajuste la dosis de inyección en función del peso corporal semanalmente durante un total de 4 semanas, con una dosis acumulada de 20 mg / kg (Figura 1). NOTA: Se eligió un período de tiempo de 4 semanas porque la ecocardiografía a las 4 semanas mostró una diferencia significativa en la función cardíaca entre los dos grupos.</li>
</ol>3. Examen ecocardiográfico
<ol><li>Al final de la cuarta semana, realice un examen ecocardiográfico de los ratones.</li>
	<li>Anestesiar a los ratones con 2% de isoflurano por vía intranasal. Si los ratones no responden a una pizca de la piel con una pinza dentada o estimulando los dedos de los pies y la cola, continúe con el protocolo.</li>
	<li>Coloque el ratón en una plataforma de manipulación de animales en posición supina. Para mantener la anestesia, cubra la nariz y la boca del animal con un cono nasal y administre isoflurano al 2%. NOTA: Para la anestesia IP, inyecte hidrato de cloral al 4% a una dosis de 0,2 ml/20 g.</li>
	<li>Retire el pelaje del pecho con cuidado con una afeitadora eléctrica. Evaluar la función cardíaca in vivo mediante ecocardiografía transtorácica.</li>
	<li>Realizar el ecocardiograma del VI tanto en las vistas paraesternales de eje largo como de eje corto a una velocidad de fotogramas de 233 Hz. Las dimensiones sistólicas finales y diastólicas finales se definieron como las fases correspondientes a la onda T del ECG y a la onda R, respectivamente.</li>
	<li>En los trazados en modo M, mida el diámetro sistólico final del VI promedio (LVIDd), el diámetro diastólico final del VI (LVID), el grosor septal interventricular (IVS) y el grosor de la pared posterior del VI (LVPW) de 3 a 5 latidos cardíacos. También calcule la fracción de eyección (EF) y el acortamiento de fracción (FS) en función de la ecocardiografía.</li>
</ol>4. Tinción histológica
<ol><li>Después del análisis ecocardiográfico, sacrificar a los ratones mediante inyección intraventricular de cloruro de potasio al 10%.</li>
	<li>Perfundir el corazón con aproximadamente 30 ml de solución salina después de la disección hasta que el hígado y el pulmón se vuelvan pálidos.</li>
	<li>Extirpe el corazón y lávelo a fondo en una solución tampón de fosfato para extruir la sangre.</li>
	<li>Fije el corazón en formalina al 4% a temperatura ambiente durante 24 h y trate el tejido en una caja de parafina para que la cera de parafina se enfríe y se solidifique.</li>
	<li>Cortar los corazones en rodajas de 5 μm de grosor para la tinción patológica.</li>
	<li>Desparar y rehidratar secciones que contengan músculo papilar.<ol>
<li>Incubar portaobjetos a 55 °C durante 30 min. Luego, incubar en xileno 2x durante 2 min cada uno; 100% etanol 2x durante 2 min cada uno; 95% de etanol 2x durante 2 min cada uno; 80% de etanol durante 2 min; 75% de etanol durante 2 min; y etanol al 50% durante 2 min.</li>
	</ol>
</li>
	<li>Tinción con hematoxilina y eosina (H&E), así como la tinción de Masson.</li>
</ol>

<ol>
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G., Semsarian, C., MacDonald, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dilated+cardiomyopathy.">Dilated cardiomyopathy.</a> Lancet. 390 (10092), 400-414 (2017).</li><li>Ichihara, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Attenuation+of+oxidative+stress+and+cardiac+dysfunction+by+bisoprolol+in+an+animal+model+of+dilated+cardiomyopathy.">Attenuation of oxidative stress and cardiac dysfunction by bisoprolol in an animal model of dilated cardiomyopathy.</a> Biochemical and Biophysical Research Communications. 350 (1), 105-113 (2006).</li><li>Fountoulakis, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alterations+in+the+heart+mitochondrial+proteome+in+a+desmin+null+heart+failure+model.">Alterations in the heart mitochondrial proteome in a desmin null heart failure model.</a> Journal of Molecular and Cellular Cardiology. 38 (3), 461-474 (2005).</li><li>Fairweather, D., Rose, N. 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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doxorubicin-induced+chronic+dilated+cardiomyopathy-the+apoptosis+hypothesis+revisited.">Doxorubicin-induced chronic dilated cardiomyopathy-the apoptosis hypothesis revisited.</a> Journal of Molecular Medicine. 95 (3), 239-248 (2017).</li><li>Zhao, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MicroRNA-140-5p+aggravates+doxorubicin-induced+cardiotoxicity+by+promoting+myocardial+oxidative+stress+via+targeting+Nrf2+and+Sirt2.">MicroRNA-140-5p aggravates doxorubicin-induced cardiotoxicity by promoting myocardial oxidative stress via targeting Nrf2 and Sirt2.</a> Redox Biology. 15, 284-296 (2018).</li><li>O'Connell, J. 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P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CTRP3+protected+against+doxorubicin-induced+cardiac+dysfunction,+inflammation+and+cell+death+via+activation+of+Sirt1.">CTRP3 protected against doxorubicin-induced cardiac dysfunction, inflammation and cell death via activation of Sirt1.</a> Journal of Molecular and Cellular Cardiology. 114, 38-47 (2018).</li><li>Sun, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+TGF-beta+pathway+mediates+doxorubicin+effects+on+cardiac+endothelial+cells.">The TGF-beta pathway mediates doxorubicin effects on cardiac endothelial cells.</a> Journal of Molecular and Cellular Cardiology. 90, 129-138 (2016).</li><li>Minotti, G., Menna, P., Salvatorelli, E., Cairo, G., Gianni, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anthracyclines:+molecular+advances+and+pharmacologic+developments+in+antitumor+activity+and+cardiotoxicity.">Anthracyclines: molecular advances and pharmacologic developments in antitumor activity and cardiotoxicity.</a> Pharmacological Reviews. 56 (2), 185-229 (2004).</li><li>Vejpongsa, P., Yeh, E. 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No se declaran conflictos de intereses.

Dox es un fármaco antitumoral antitumoral inespecífico de uso común en la práctica clínica12. Su principal efecto secundario es la cardiotoxicidad, caracterizada por miocardiopatía y posterior insuficiencia cardíaca13. El mecanismo subyacente incluye el daño de la peroxidación lipídica miocárdica, la inhibición del retículo sarcoplásmico miocárdico Ca2+-ATPasa y la activación del sistema miocárdico local de renina-angiotensina, lo que resulta en ...

An erratum was issued for:&#160;<a href="https://www.jove.com/t/61158">A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo</a>. A figure was updated.
Figure 1 was updated from:
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61158/61158fig1v2.jpg" /> 
Figure 1: Schematic diagram of a Dox-induced dilated cardiomyopathy. <a href="https://www.jove.com/files/ftp_upload/61158/61158fig1v2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
to:
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61158/61158fig1v5.jpg" /> 
Figure 1: Schematic diagram of a Dox-induced dilated cardiomyopathy. <a href="https://www.jove.com/files/ftp_upload/61158/61158fig1v5large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

An erratum was issued for:&#160;<a href="https://www.jove.com/t/61158">A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo</a>. A figure was updated.

Erratum: A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo

Una de las causas más comunes de insuficiencia cardíaca, la DCM se caracteriza por la dilatación ventricular y la disminución de la función cardíaca y es la razón más común para el trasplante de corazón en todo el mundo1. Para investigar más a fondo su patogénesis y encontrar tratamientos efectivos, el acceso a modelos animales maduros es especialmente importante. El propósito de los experimentos descritos es establecer un modelo de ratón estable de DCM que se asemeje al DCM humano.
Debido a la compleja patogénesis de DCM, hay muchos métodos diferentes para hacer modelos animales correspondientes. Los modelos2 de DCM espontáneos son relativamente estables, pero son caros y no están fácilmente disponibles. Los modelos animales modificados genéticamente3 no están bien establecidos y requieren un uso más experimental. Los modelos animales DCM inducidos por infección viral4 o defectos autoinmunes5 son fáciles de obtener, pero no son totalmente representativos de DCM. Los modelos asociados con la toxicidad miocárdica incluyen modelos DCM inducidos por alcohol y modelos animales DCM inducidos por Dox.
El modelo de miocardiopatía inducida por Dox se obtiene mediante inyección intraperitoneal de Dox6. El modelo explota el efecto secundario crónico más grave de Dox: Después de la exposición a Dox, los pacientes desarrollan síntomas de DCM de inicio tardío con uniformidad clínica7. El estrés oxidativo inducido por Dox8 y el daño mitocondrial9,que conducen a la apoptosis de los cardiomiocitos, son síntomas en la patogénesis de dcM. Existen modelos de tratamiento dox agudo y crónico: una sola dosis alta de Dox (15 mg/kg) induce un modelo a corto plazo para la miocardiopatía10,mientras que las inyecciones repetitivas de Dox en dosis bajas (seis semanales, 3 mg/kg) inducen un modelo a largo plazo para la miocardiopatía11. Según el estudio presentado, los ratones de tipo salvaje inyectados por vía intraperitoneal una vez a la semana durante un mes a una dosis de 5 mg / kg muestran morfología e histología del corazón consistentes con las características de DCM al final del tratamiento, proporcionando una forma ideal de establecer un modelo de DCM.

<table><tbody><tr><td>4% paraformaldehyde</td><td>servicebio</td><td>CAS30525-89-4</td><td></td></tr><tr><td>C57BL/6 mice</td><td>Model Animal Research Center of Nanjing University</td><td>\</td><td></td></tr><tr><td>Doxorubicin hydrochloride</td><td>Pfizer</td><td>CAS25316-40-9</td><td></td></tr><tr><td>echocardiography</td><td>Visualsonics</td><td>\</td><td></td></tr><tr><td>Hematoxylin and Eosin staining kit</td><td>Solarbio</td><td>G1120</td><td></td></tr><tr><td>Masson staining kit</td><td>Solarbio</td><td>G1343</td><td></td></tr><tr><td>phosphate buffer solution</td><td>Sigma</td><td>P5368</td><td></td></tr><tr><td>potassium chloride</td><td>Sigma</td><td>CAS7447-40-7</td><td></td></tr><tr><td>sterilized syringe</td><td>Millipore</td><td>SLGP033RB</td><td></td></tr></tbody></table>

a doxorubicin-induced murine model of dilated cardiomyopathy in vivo

La miocardiopatía dilatada (MCD) se refiere a un espectro de trastornos miocárdicos heterogéneos caracterizados por dilatación ventricular y rendimiento cardíaco deprimido en ausencia de hipertensión, enfermedades cardíacas valvulares, congénitas o isquémicas, y que pueden estar relacionados con infecciones, anomalías autoinmunes o metabólicas, o herencia familiar. Puede progresar a insuficiencia cardíaca congestiva con un mal pronóstico. La doxorrubicina (Dox) se emplea ampliamente como un fármaco quimioterapéutico, pero su uso es limitado porque causa cambios similares a la DCM del miocardio. Su toxicidad miocárdica se atribuye al estrés oxidativo, la inflamación crónica y la apoptosis cardiomiocita. No se ha establecido un modelo de DCM que explote estos síntomas de DCM inducidos por Dox.

Función cardíaca La miocardiopatía dilatada se caracteriza por dilatación ventricular progresiva y disfunción contráctil. La Figura 2 muestra imágenes ecocardiográficas representativas de los dos grupos. Los ratones tratados con Dox mostraron una fracción de eyección del ventrículo izquierdo marcadamente reducida y acortamiento fraccional del ventrículo izquierdo(Figura 3A,B). El diámetro del VI también aumentó...

Watch this Scientific Journal Video about A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo at JoVE.com

A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo

Se describe un protocolo para establecer un modelo de miocardiopatía dilatada (MCD) inducida por doxorrubicina en ratones mediante inyección intraperitoneal a largo plazo de doxorrubicina.

Un modelo murino inducido por doxorrubicina de miocardiopatía dilatada in vivo

Dilated cardiomyopathy (DCM) refers to a spectrum of heterogeneous myocardial disorders characterized by ventricular dilation and depressed cardiac ...

a-doxorubicin-induced-murine-model-of-dilated-cardiomyopathy-in-vivo

Research

JoVE Journal

Medicine

4.4K vistas.  Clinical College of Nanjing Medical University. Se describe un protocolo para establecer un modelo de miocardiopatía dilatada (MCD) inducida por doxorrubicina en ratones mediante inyección intraperitoneal a largo plazo de doxorrubicina.

Video: A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo

Displacement Analysis of Myocardial Mechanical Deformation (DIAMOND) Reveals Segmental Heterogeneity of Cardiac Function in Embryonic Zebrafish

Zebrafish are increasingly utilized as a model organism for cardiomyopathies and regeneration. Current methods evaluating cardiac function fail to reliably detect segmental mechanics and are not readily feasible in zebrafish. Here we present a semiautomated, open-source method for the quantitative assessment of four-dimensional (4D) segmental cardiac function: displacement analysis of myocardial mechanical deformation (DIAMOND). Transgenic embryonic zebrafish were imaged in vivo using a light-sheet fluorescence microscopy system with 4D cardiac motion synchronization. Acquired 3D digital hearts were reconstructed at end-systole and end-diastole, and the ventricle was manually segmented into binary datasets. Then, the heart was reoriented and isotropically resampled along the true short axis, and the ventricle was evenly divided into eight portions (I&#8211;VIII) along the short axis. Due to the different resampling planes and matrices at end-systole and end-diastole, a transformation matrix was applied for image registration to restore the original spatial relationship between the resampled systolic and diastolic image matrices. After image registration, the displacement vector of each segment from end-systole to end-diastole was calculated based on the displacement of mass centroids in three dimensions (3D). DIAMOND shows that basal myocardial segments adjacent to the atrioventricular canal undergo the highest mechanical deformation and are the most susceptible to doxorubicin-induced cardiac injury. Overall, DIAMOND provides novel insights into segmental cardiac mechanics in zebrafish embryos beyond traditional ejection fraction (EF) under both physiological and pathological conditions.

Displacement Analysis of Myocardial Mechanical Deformation DIAMOND Reveals Segmental Heterogeneity of Cardiac Function in Embryonic Zebrafish

The goal of this protocol is to detail a novel method for the assessment of segmental cardiac function in embryonic zebrafish under both physiological and pathological conditions.

El análisis de desplazamiento de la deformación mecánica miocárdica (DIAMOND) revela la heterogeneidad segmentaria de la función cardíaca en el pez cebra embrionario

Zebrafish are increasingly utilized as a model organism for cardiomyopathies and regeneration. Current methods evaluating cardiac function fail to ...

Investigación

Biología del Desarrollo

Permanent Ligation of the Left Anterior Descending Coronary Artery in Mice: A Model of Post-myocardial Infarction Remodelling and Heart Failure

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It is characterized by fluid retention, shortness of breath, and fatigue, in particular on exertion. Heart failure is a growing public health problem, the leading cause of hospitalization, and a major cause of mortality. Ischemic heart disease is the main cause of heart failure.
Ventricular remodelling refers to changes in structure, size, and shape of the left ventricle. This architectural remodelling of the left ventricle is induced by injury (e.g., myocardial infarction), by pressure overload (e.g., systemic arterial hypertension or aortic stenosis), or by volume overload. Since ventricular remodelling affects wall stress, it has a profound impact on cardiac function and on the development of heart failure. A model of permanent ligation of the left anterior descending coronary artery in mice is used to investigate ventricular remodelling and cardiac function post-myocardial infarction. This model is fundamentally different in terms of objectives and pathophysiological relevance compared to the model of transient ligation of the left anterior descending coronary artery. In this latter model of ischemia/reperfusion injury, the initial extent of the infarct may be modulated by factors that affect myocardial salvage following reperfusion. In contrast, the infarct area at 24 hr after permanent ligation of the left anterior descending coronary artery is fixed. Cardiac function in this model will be affected by 1) the process of infarct expansion, infarct healing, and scar formation; and 2) the concomitant development of left ventricular dilatation, cardiac hypertrophy, and ventricular remodelling.
Besides the model of permanent ligation of the left anterior descending coronary artery, the technique of invasive hemodynamic measurements in mice is presented in detail.

Heart failure is the leading cause of hospitalization and a major cause of mortality. A model of permanent ligation of the left anterior descending coronary artery in mice is applied to investigate ventricular remodelling and cardiac dysfunction post-myocardial infarction. The technique of invasive hemodynamic measurements in mice is presented.

La ligadura permanente de la arteria coronaria descendente anterior en ratones: un modelo de remodelación post infarto de miocardio e insuficiencia cardiaca

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It ...

Medicina

Preclinical Cardiac Electrophysiology Assessment by Dual Voltage and Calcium Optical Mapping of Human Organotypic Cardiac Slices

Human cardiac slice preparations have recently been developed as a platform for human physiology studies and therapy testing to bridge the gap between animal and clinical trials. Numerous animal and cell models have been used to examine the effects of drugs, yet these responses often differ in humans. Human cardiac slices offer an advantage for drug testing in that they are directly derived from viable human hearts. In addition to having preserved multicellular structures, cell-cell coupling, and extracellular matrix environments, human cardiac tissue slices can be used to directly test the effect of innumerable drugs on adult human cardiac physiology. What distinguishes this model from other heart preparations, such as whole hearts or wedges, is that slices can be subjected to longer-term culture. As such, cardiac slices allow for studying the acute as well as chronic effects of drugs. Furthermore, the ability to collect several hundred to a thousand slices from a single heart makes this a high-throughput model to test several drugs at varying concentrations and combinations with other drugs at the same time. Slices can be prepared from any given region of the heart. In this protocol, we describe the preparation of left ventricular slices by isolating tissue cubes from the left ventricular free wall and sectioning them into slices using a high precision vibrating microtome. These slices can then either be subjected to acute experiments to measure baseline cardiac electrophysiological function or cultured for chronic drug studies. This protocol also describes dual optical mapping of cardiac slices for simultaneous recordings of transmembrane potentials and intracellular calcium dynamics to determine the effects of the drugs being investigated.

This protocol describes the procedure for sectioning and culturing human cardiac slices for preclinical drug testing and details the use of optical mapping for recording transmembrane voltage and intracellular calcium signals simultaneously from these slices.

Evaluación de electrofisiología cardíaca preclínica por doble voltaje y mapeo óptico de calcio de cortes cardíacos organotípicos humanos

Human cardiac slice preparations have recently been developed as a platform for human physiology studies and therapy testing to bridge the gap between ...

Bioingeniería

Percutaneous Contrast Echocardiography-guided Intramyocardial Injection and Cell Delivery in a Large Preclinical Model

Cell and gene therapy are exciting and promising strategies for the purpose of cardiac regeneration in the setting of heart failure with reduced ejection fraction (HFrEF). Before they can be considered for use, and implemented in humans, extensive preclinical studies are required in large animal models to evaluate the safety, efficacy, and fate of the injectate (e.g., stem cells) once delivered into the myocardium. Small rodent models offer advantages (e.g., cost effectiveness, amenability for genetic manipulation); however, given inherent limitations of these models, the findings in these rarely translate into the clinic. Conversely, large animal models such as rabbits, have advantages (e.g., similar cardiac electrophysiology compared to humans and other large animals), whilst retaining a good cost-effective balance. Here, we demonstrate how to perform a percutaneous contrast echocardiography-guided intramyocardial injection (IMI) technique, which is minimally invasive, safe, well tolerated, and very effective in the targeted delivery of injectates, including cells, into several locations within the myocardium of a rabbit model. For the implementation of this technique, we also have taken advantage of a widely available clinical echocardiography system. After putting in practice the protocol described here, a researcher with basic ultrasound knowledge will become competent in the performance of this versatile and minimally invasive technique for routine use in experiments, aimed at hypothesis testing of the capabilities of cardiac regenerative therapeutics in the rabbit model. Once competency is achieved, the whole procedure can be performed within 25 min after anaesthetizing the rabbit.

Novel therapeutic strategies in cardiac regenerative medicine require extensive and detailed studies in large preclinical animal models before they can be considered for use in humans. Here, we demonstrate a percutaneous contrast echocardiography-guided intramyocardial injection technique in rabbits, which is valuable for hypothesis testing the efficacy of such novel therapies.

Inyección de contraste percutánea guiada por ecocardiografía intramiocárdica y entrega de celular en un modelo preclínico grande

Cell and gene therapy are exciting and promising strategies for the purpose of cardiac regeneration in the setting of heart failure with reduced ejection ...

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine

A stable and reliable model of chronic heart failure is required for many experiments to understand hemodynamics or to test effects of new treatment methods. Here, we present such a model by tachycardia-induced cardiomyopathy, which can be produced by rapid cardiac pacing in swine.
A single pacing lead is introduced transvenously into fully anaesthetized healthy swine, to the apex of the right ventricle, and fixated. Its other end is then tunneled dorsally to the paravertebral region. There, it is connected to an in-house modified heart pacemaker unit that is then implanted in a subcutaneous pocket. 
After 4 - 8 weeks of rapid ventricular pacing at rates of 200 - 240 beats/min, physical examination revealed signs of severe heart failure - tachypnea, spontaneous sinus tachycardia, and fatigue. Echocardiography and X-ray showed dilation of all heart chambers, effusions, and severe systolic dysfunction. These findings correspond well to decompensated dilated cardiomyopathy and are also preserved after the cessation of pacing.
This model of tachycardia-induced cardiomyopathy can be used for studying the pathophysiology of progressive chronic heart failure, especially hemodynamic changes caused by new treatment modalities like mechanical circulatory supports. This methodology is easy to perform and the results are robust and reproducible.

Here, we present a protocol to produce tachycardia-induced cardiomyopathy in swine. This model represents a potent way to study the hemodynamics of progressive chronic heart failure and the effects of applied treatment.

Cardiomiopatía Taquicardia-inducida como un modelo de insuficiencia cardíaca crónica en porcino

A stable and reliable model of chronic heart failure is required for many experiments to understand hemodynamics or to test effects of new treatment ...

A Doxorubicin-induced Cardiomyopathy Model in Adult Zebrafish

The genetically accessible adult zebrafish (Danio rerio) has been increasingly used as a vertebrate model for understanding human diseases such as cardiomyopathy. Because of its convenience and amenability to high throughput genetic manipulations, the generation of acquired cardiomyopathy models, such as the doxorubicin-induced cardiomyopathy (DIC) model in adult zebrafish, is opening the doors to new research avenues, including discovering cardiomyopathy modifiers via forward genetic screening. Different from the embryonic zebrafish DIC model, both initial acute and later chronic phases of cardiomyopathy can be determined in the adult zebrafish DIC model, enabling the study of stage-dependent signaling mechanisms and therapeutic strategies. However, variable results can be obtained with the current model, even in the hands of experienced investigators. To facilitate future implementation of the DIC model, we present a detailed protocol on how to generate this DIC model in adult zebrafish and describe two alternative ways of intraperitoneal (IP) injection. We further discuss options on how to reduce variations to obtain reliable results and provide suggestions on how to appropriately interpret the results.

A method to generate a doxorubicin-induced cardiomyopathy model in adult zebrafish (Danio rerio) is described here. Two alternative ways of intraperitoneal injection are presented and conditions to reduce variations among different experimental groups are discussed.

Un modelo de cardiomiopatía inducida por la doxorrubicina en pez cebra adulto

The genetically accessible adult zebrafish (Danio rerio) has been increasingly used as a vertebrate model for understanding human diseases such as ...

Murine Myocardial Infarction Model using Permanent Ligation of Left Anterior Descending Coronary Artery

Myocardial infarction (MI) and acute coronary diseases are among the most prominent causes of death in population with western lifestyle. The murine models of MI with permanent ligation of left-anterior descending (LAD) coronary artery closely mimics MI in humans. Murine models benefit from the extensive genetic engineering available nowadays. Here we propose a reproducible murine surgical model of myocardial infarction by permanent LAD coronary ligation. Our technique comprises anesthesia with ketamine/xylazine that can be rapidly reversed by administration of an antagonist, intubation without tracheotomy for mechanical-assisted ventilation, ventilation with application of extrinsic positive end-expiratory pressure (PEEP) to avoid alveolar collapse, a thoracotomy method limiting to the minimum surgical lesions made to skeletal muscles, and lung inflation without thoracentesis. This method is sparsely invasive, reproducible and reduces post-surgery mortality and complications.

Herein we describe a surgical procedure showing how to achieve permanent ligation of the left-anterior descending coronary artery in mice. This model is of high relevance to investigate the pathophysiology of myocardial infarction and the concomitant biological processes.

Modelo de infarto de miocardio murino usando ligadura permanente de la arteria coronaria descendente anterior izquierda

Myocardial infarction (MI) and acute coronary diseases are among the most prominent causes of death in population with western lifestyle. The murine ...

Revealing Subtle Changes in Cardiac Function using Transthoracic Dobutamine Stress Echocardiography in Mice

Left ventricular (LV) dysfunction paves the final pathway for a multitude of cardiac disorders. With the non-invasive high-frequency transthoracic dobutamine stress echocardiography in humans, a reductionist investigation approach to unmask subtle changes in cardiac function has become possible. Here, we provide a protocol for using this technique in mice to facilitate expanded analysis of LV architecture and function in physiology and pathology enabling the observation of alterations in models of cardiac disease hidden in unstressed hearts. This investigation can be performed in one and the same animal and allows both, basal and pharmacologically stress-induced measurements. We outline detailed criteria for appropriate anesthesia, imaging-based LV analysis, consideration of intra- and interobserver variability, and obtaining positive inotrope response that can be attained in mice after intraperitoneal injection of dobutamine under near physiological conditions. To recapitulate the characteristics of human physiology and disease in small animal models, we highlight critical pitfalls in evaluation, e.g., a pronounced Bowditch effect in mice. To further meet translational objectives, we compare stress-induced effects in humans and mice. When used in translational studies, attention must be paid to physiological differences between mice and human. Experimental rigor dictates that some parameters assessed in patients can only be used with caution due to restrictions in spatial and temporal resolution in mouse models.

Left ventricular dysfunction constitutes the final common pathway for a host of cardiac disorders. We here provide a detailed protocol of transthoracic dobutamine stress echocardiography approach for comprehensive evaluation of the left ventricular function of mouse models of cardiac disease as well as cardiac phenotyping.

Left ventricular (LV) dysfunction paves the final pathway for a multitude of cardiac disorders. With the non-invasive high-frequency transthoracic ...

An Experimental Model of Myocardial Infarction for Studying Cardiac Repair and Remodeling in Knockout Mice

Cardiovascular disease is the most prevalent cause of death in Western countries, with acute myocardial infarction (MI) being the most prevalent form. This paper describes a protocol for studying the role of galectin 3 (Gal-3) in the temporal evolution of cardiac healing and remodeling in an experimental animal model of MI. 
The procedures described include an experimental model of MI with a permanent coronary ligature in male C57BL/6J (control) and Gal-3 knockout (KO) mice, an echocardiography procedure to study cardiac remodeling and systolic function in vivo, a histological evaluation of interstitial myocardial fibrosis with picrosirius red-stained and rhodamine-conjugated lectin-stained sections for studying myocyte hypertrophy by the cross-sectional area (MCSA), and the quantification of infarct size and cardiac remodeling (scar thinning, septum thickness, and expansion index) by planimetry in slices stained with Masson's trichrome and triphenyl tetrazolium chloride. Gal-3 KO mice with MI showed disrupted cardiac remodeling and an increase in the scar thinning ratio and the expansion index. At the onset of MI, myocardial function and cardiac remodeling were also severely affected. At 4 weeks post MI, the natural evolution of fibrosis in infarcted Gal-3 KO mice was also affected. 
In summary, the experimental model of MI is a suitable model for studying the temporal evolution of cardiac repair and remodeling in mice with the genetic deletion of Gal-3 and other animal models. The lack of Gal-3 affects the dynamics of cardiac repair and disrupts the evolution of cardiac remodeling and function after MI.

Here, we describe an experimental model of myocardial infarction, an echocardiography procedure to study cardiac remodeling and function, and procedures for quantifying fibrosis and hypertrophy in picrosirius red-stained and rhodamine-stained sections, as well as the infarct size and expansion index in slices stained with Masson's trichrome.

Cardiovascular disease is the most prevalent cause of death in Western countries, with acute myocardial infarction (MI) being the most prevalent form. ...

<meta charset="utf8"></head><body>Modelo murino para miocardiopatía diabética mediante dieta alta en grasas e inyección de STZ

Modeling and Evaluation of Murine Diabetic Cardiomyopathy Model

The underlying pathophysiological mechanisms of diabetic cardiomyopathy (DbCM), a leading cause of mortality among patients with type 2 diabetes mellitus (T2DM), remain poorly understood. The myocardial toxicity associated with T2DM is attributed to factors such as lipotoxicity, glucotoxicity, oxidative stress, reduced cardiac efficiency, and lipoapoptosis. Compared to rats, mice offer greater accessibility, cost-effectiveness, and broader applicability for animal experiments. Insulin resistance and impaired insulin secretion are crucial factors in the pathophysiology of T2DM. We introduce a novel nongenetic murine model that replicates the progression of human DbCM induced by a combination of high-fat diet (HFD) feeding and streptozotocin (STZ) injection. In this study, we used wild-type C57BL/6J mice, administering an HFD regimen for 12 weeks, followed by intraperitoneal injections of STZ for an additional 12 weeks to induce characteristic manifestations of T2DM. We conducted oral glucose tolerance tests and measured serum insulin concentrations to confirm the development of insulin resistance and insufficient insulin secretion. Cardiac structure and function were rigorously assessed through noninvasive transthoracic echocardiography. Pathological characteristics were evaluated through Masson's trichrome staining and wheat germ agglutinin (WGA) staining, revealing pathological features related to DbCM. Therefore, we provide a robust and versatile method for establishing a nongenetic murine model of DbCM.

<meta charset="utf8"></head><body>Modelado y evaluación del modelo de miocardiopatía diabética murina

This protocol outlines a method for inducing diabetic cardiomyopathy through a combination of high-fat diet feeding and streptozotocin injection. This approach aims to provide a reliable framework for scientific investigation into diabetic cardiomyopathy and to explore potential avenues for clinical treatment applications.

Modelado y evaluación del modelo de miocardiopatía diabética murina

The underlying pathophysiological mechanisms of diabetic cardiomyopathy (DbCM), a leading cause of mortality among patients with type 2 diabetes mellitus ...