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El nitrato derivado del huésped aumenta el crecimiento de E. coli en el intestino inflamado
Sebastian E Winter1, Maria G Winter, Mariana N Xavier
1Department of Medical Microbiology and Immunology, School of Medicine, University of California, Davis, One Shields Avenue, Davis, CA, USA.
Science (New York, N.Y.)
|February 9, 2013
Resumen
La inflamación en el intestino genera nitrato, una molécula que alimenta el crecimiento de ciertas bacterias como E. coli. Este nitrato derivado del huésped promueve selectivamente las bacterias comensales beneficiosas durante la inflamación intestinal.
Área de la Ciencia:
- Microbiología Microbiología.
- Inmunología Inmunología.
- Gastroenterología y Gastroenterología.
Sus antecedentes:
- Los trastornos inflamatorios intestinales alteran la estructura de la comunidad microbiana.
- Se caracteriza por una disminución de los anaeróbios obligados y un aumento de los anaeróbicos facultativos Enterobacteriaceae.
- Los mecanismos que vinculan la respuesta del huésped a los cambios microbianos son poco conocidos.
Objetivo del estudio:
- Para investigar cómo las respuestas inflamatorias del huésped dan forma a la estructura de la comunidad microbiana intestinal.
- Para identificar el papel de las moléculas derivadas del huésped en el crecimiento bacteriano durante la inflamación.
Principales métodos:
- Utilizó un modelo de ratón de inflamación intestinal.
- Se administró nitrato y se evaluó su impacto en el crecimiento de Escherichia coli.
- Se examinaron ratones con deficiencia de sintasa de óxido nítrico inducible para rastrear el origen de los nitratos.
Principales resultados:
- El nitrato generado durante la inflamación confería una ventaja de crecimiento a Escherichia coli en el intestino grueso.
- Los ratones que carecían de sintasa de óxido nítrico inducible no apoyaron la respiración de nitrato de E. coli, lo que indica nitrato derivado del huésped.
- La respuesta inflamatoria del huésped selectivamente promueve el crecimiento de las Enterobacteriaceae comensales.
Conclusiones:
- El nitrato derivado del huésped, un subproducto de la inflamación, selectivamente mejora el crecimiento de las Enterobacteriaceae comensales.
- Este mecanismo implica la generación de aceptores de electrones para la respiración anaeróbica por las bacterias.
- Comprender esta interacción es crucial para el manejo de los trastornos inflamatorios intestinales.
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