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El factor de necrosis tumoral alfa inhibe el efecto estimulante de la insulina sobre la absorción de glucosa y la
Christian Rask-Madsen1, Helena Domínguez, Nikolaj Ihlemann
1Joslin Diabetes Center, Section on Vascular Cell Biology and Complications, One Joslin Place, Room 4504, Boston, Mass 02215, USA. christian.rask-madsen@joslin.harvard.edu
Circulation
|October 8, 2003
Resumen
El factor de necrosis tumoral alfa (TNF-alfa) afecta significativamente la absorción de glucosa estimulada por insulina y la función endotelial en los seres humanos. Esto sugiere que el TNF-alfa contribuye a la resistencia a la insulina tanto en los músculos como en los tejidos vasculares.
Área de la Ciencia:
- Fisiología humana fisiología humana.
- Trastornos metabólicos Los trastornos metabólicos incluyen trastornos metabólicos.
- La inflamación es la inflamación.
Sus antecedentes:
- Los mecanismos inflamatorios están implicados en la resistencia a la insulina y la aterosclerosis.
- El factor de necrosis tumoral alfa (TNF-alfa) es una citoquina proinflamatoria clave.
Objetivo del estudio:
- Investigar si el TNF-alfa inhibe la absorción de glucosa estimulada por insulina en humanos.
- Para examinar el efecto del TNF-alfa en la función endotelial estimulada por insulina.
Principales métodos:
- Voluntarios varones sanos se sometieron a infusiones de la arteria braquial.
- Se realizaron estudios de dosis-respuesta con acetilcolina (ACh) y nitroprussida de sodio (SNP).
- La insulina y/o el TNF-alfa fueron coinfusionados para evaluar los efectos sobre la absorción de glucosa y el flujo sanguíneo.
Principales resultados:
- La absorción de glucosa del antebrazo estimulada por insulina aumentó en un 220%, pero fue completamente inhibida por el TNF-alfa.
- TNF-alfa inhibió significativamente el flujo sanguíneo del antebrazo inducido por ACh, particularmente durante la infusión de insulina.
- La inhibición de la respuesta ACh por el TNF-alfa fue probablemente mediada por la reducción de la producción de óxido nítrico (NO).
Conclusiones:
- El TNF-alfa juega un papel en el desarrollo de la resistencia a la insulina en el músculo humano.
- TNF-alfa contribuye a la disfunción vascular, lo que sugiere un papel en el desarrollo de la aterosclerosis.
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