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A Flow Cytometry-based Assay for Measuring Mitochondrial Membrane Potential in Cardiac Myocytes After Hypoxia/Reoxygenation
Published on: July 13, 2018
Las vías de señalización en la apoptosis de los cardiomiocitos inducida por especies reactivas de oxígeno inducida
R von Harsdorf1, P F Li, R Dietz
1Department of Cardiology, Franz Volhard Clinic, Humboldt-University, Berlin, Germany. rharsdo@mdc-berlin.de
Circulation
|June 9, 1999
Resumen
Las especies reactivas de oxígeno (ROS) desencadenan la apoptosis en las células del corazón a través de vías distintas. El peróxido de hidrógeno activa la vía intrínseca, mientras que el anión superóxido utiliza una ruta diferente que involucra a Mch2alpha, destacando ROS.
Área de la Ciencia:
- Biología Cardiovascular Biología Cardiovascular
- La señalización celular.
- El estrés oxidativo Investigación de la investigación
Sus antecedentes:
- La interacción entre la homeostasis de los radicales libres, la apoptosis y la salud cardíaca no se entiende bien.
- Investigar el papel de las especies reactivas de oxígeno (ROS) en la apoptosis de los cardiomiocitos es crucial para comprender las enfermedades cardíacas.
Objetivo del estudio:
- Para determinar si las ROS pueden inducir la apoptosis en los cardiomiocitos.
- Para dilucidar las vías moleculares específicas involucradas en la apoptosis de cardiomiocitos mediada por ROS.
Principales métodos:
- Utilizó un modelo de cultivo de células cardíacas aisladas.
- Empleó varios sistemas generadores de ROS (H2O2, anión superóxido).
- Se analizó la expresión de proteínas (p53, Bax, Bcl-2, Bad), la translocación de proteínas y la activación de enzimas (CPP32, Mch2alpha).
Principales resultados:
- Tanto el H2O2 como el anión superóxido indujeron la apoptosis de los cardiomiocitos.
- La apoptosis inducida por H2O2 involucró p53, Bax, translocación Bad, liberación del citocromo c y activación del CPP32.
- La apoptosis inducida por aniones de superóxido utilizó la activación de Mch2alpha y la escisión de la lámina A, distinta de la vía H2O2.
Conclusiones:
- Los ROS juegan un papel importante en la fisiopatología de las enfermedades cardíacas que implican la muerte celular apoptótica.
- Las distintas ROS desencadenan la apoptosis de los cardiomiocitos a través de cascadas de señalización separadas, ofreciendo objetivos terapéuticos potenciales.
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