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Selection of Aptamers for Amyloid β-Protein, the Causative Agent of Alzheimer's Disease
Published on: May 13, 2010
El entorno del sitio activo del péptido β amiloide unido al hemo asociado con la enfermedad de Alzheimer
Debajyoti Pramanik1, Somdatta Ghosh Dey
1Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India 700032.
Journal of the American Chemical Society
|December 15, 2010
Resumen
La enfermedad de Alzheimer implica la unión del hemo a los péptidos amiloide-beta (Aβ). Los principales residuos, la histidina 13 y la arginina 5, son cruciales para la formación del complejo hemo-Aβ y la actividad de la peroxidasa, lo que podría explicar la patología de la EA.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- La bioquímica es la bioquímica.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La enfermedad de Alzheimer (EA) se asocia con un aumento del hemo en el cerebro temporal.
- El hemo se une a los péptidos amiloide-beta (Aβ), formando complejos que contribuyen a la patología de la EA, incluida la desregulación del hierro y el estrés oxidativo.
Objetivo del estudio:
- Para caracterizar el sitio activo de unión al hemo en los péptidos Aβ.
- Para identificar los residuos clave involucrados en la formación del complejo hemo-Aβ y la actividad de la peroxidasa.
Principales métodos:
- Se utilizaron péptidos Aβ de tipo salvaje y mutados para investigar la interacción del hemo.
- Se realizaron ensayos de peroxidasa y perturbaciones del pH en complejos hemo-Aβ.
Principales resultados:
- Identificó la histidina 13 (His13) y la histidina 14 (His14) como residuos de unión al hemo bajo condiciones fisiológicas.
- Se determinó que la arginina 5 (Arg5) es un residuo crítico de segunda esfera, esencial para la actividad de la peroxidasa de los complejos hemo-Aβ.
- Se observó que His13 y Arg5 están ausentes en roedores, que no exhiben AD.
Conclusiones:
- El estudio aclara los detalles moleculares del sitio activo del hemo-Aβ.
- His13 y Arg5 juegan un papel importante en la formación del complejo hemo-Aβ y la actividad de la peroxidasa, implicándolos en la patogénesis de la enfermedad de Alzheimer.
- La ausencia de estos residuos en roedores puede explicar su falta de patología AD.
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