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La calcificación de la válvula aórtica humana está asociada con un fenotipo de osteoblastos
Nalini M Rajamannan1, Malayannan Subramaniam, David Rickard
1Division of Cardiology, Northwestern University Feinberg School of Medicine, Northwestern University, 201 East Huron St, Galter Suite 10-240, Chicago, Ill 60611, USA. n.rajamannan@northwestern.edu
Circulation
|April 30, 2003
Resumen
La calcificación de la válvula aórtica, una enfermedad cardiovascular común, implica un proceso activo y regulado similar a la formación ósea. Este proceso está vinculado a un fenotipo similar al de los osteoblastos, lo que sugiere un mecanismo regulado en lugar de una degeneración aleatoria.
Área de la Ciencia:
- Biología Cardiovascular Biología Cardiovascular
- Metabolismo óseo Metabolismo óseo.
- La biomineralización es la biomineralización.
Sus antecedentes:
- La estenosis aórtica calcifica es una enfermedad cardiovascular prevalente.
- El mecanismo subyacente de la calcificación de la válvula aórtica aún no se entiende por completo.
- Una hipótesis sugiere similitud con la formación ósea esquelética mediada por células similares a los osteoblastos.
Objetivo del estudio:
- Para investigar el mecanismo de la calcificación de la válvula aórtica.
- Para determinar si la calcificación de la válvula aórtica implica un fenotipo similar al de los osteoblastos.
- Para comparar la expresión de genes y proteínas en válvulas aórticas humanas calcificadas frente a las normales.
Principales métodos:
- Análisis de las válvulas aórticas humanas (n=22 calcificadas, n=20 normales) utilizando microradiografía y micro-CT.
- Coloración histológica (von Kossa, Goldner) para identificar la mineralización.
- Microscopía electrónica y espectroscopia dispersiva de energía para ultrastructura y análisis elemental.
- Reacción en cadena de la transcriptasa-polimerasa inversa (RT-PCR) para los marcadores de los osteoblastos (osteopontina, sialoproteína ósea, osteocalcina, fosfatasa alcalina, Cbfa1).
Principales resultados:
- La microradiografía y el micro-CT confirmaron la calcificación de la válvula.
- Las manchas histológicas y la microscopía electrónica identificaron hidroxiapatita y la composición de CaPO4.
- La RT-PCR mostró un aumento de los niveles de ARNm para la osteopontina, la sialoproteína ósea, la osteocalcina y la Cbfa1 en las válvulas calcificadas.
- La fosfatasa alcalina mostró una mayor expresión de proteínas, pero no de ARNm, en válvulas enfermas.
Conclusiones:
- La calcificación de la válvula aórtica es un proceso activo y regulado.
- El proceso está asociado con un fenotipo celular similar al de los osteoblastos.
- Los hallazgos apoyan un mecanismo similar a la formación ósea en la calcificación de la válvula aórtica.
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