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El factor de necrosis tumoral alfa provoca una respuesta de crecimiento hipertrófico en los miocitos cardíacos
T Yokoyama1, M Nakano, J L Bednarczyk
1Department of Medicine, Veterans Administration Medical Center, Houston, TX, USA.
Circulation
|March 4, 1997
Resumen
El factor de necrosis tumoral alfa (TNF-alfa) promueve el crecimiento de los miocitos cardíacos al aumentar la síntesis de proteínas y disminuir la degradación. Esta citoquina puede ser crucial para mantener la homeostasis del tejido cardíaco después del estrés.
Área de la Ciencia:
- Biología Cardiovascular Biología Cardiovascular
- La señalización celular.
- Investigación de citoquinas Investigación de citoquinas.
Sus antecedentes:
- El factor de necrosis tumoral alfa (TNF-alfa) es una citoquina con diversos efectos.
- Los miocitos cardíacos expresan TNF-alfa después del estrés.
- El TNF-alfa puede ayudar a la homeostasis tisular después de una lesión.
Objetivo del estudio:
- Para investigar el impacto del TNF-alfa en la síntesis de proteínas en miocitos cardíacos adultos cultivados.
Principales métodos:
- Los miocitos cardíacos felinos adultos fueron estimulados con diferentes concentraciones de TNF-alfa.
- Se midieron la síntesis de proteínas y las tasas de degradación.
- La especificidad se confirmó utilizando anticuerpos neutralizantes y medio acondicionado.
- Se evaluaron las interacciones célula-sustrato.
Principales resultados:
- TNF-alfa aceleró la síntesis general de proteínas y disminuyó la degradación de las proteínas.
- La síntesis neta de actina aumentó 2.4 veces, y la síntesis de miosina de cadena pesada aumentó 3.3 veces.
- Los efectos del TNF-alfa dependían de las interacciones célula-sustrato.
Conclusiones:
- El TNF-alfa induce una respuesta de crecimiento hipertrófico en los miocitos cardíacos.
- El TNF-alfa puede desempeñar un papel importante en la homeostasis miocárdica después del estrés.
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