2) La reducción de biodisponibilidad de IGF-1: Como se menciono previamente fenómenos de fosforilación de la IGFPB-I han sido demostrados en diabéticos y su influencia en el riesgo CV aun no se ha investigado (13).

En relación a este punto, un estudio clínico en sujetos ancianos encontró correlación entre concentraciones séricas elevadas de IGFPB-1 y bajas de IGF-1 libre y presencia de signos o síntomas de enfermedad cardiovascular (ECV) (38). Controversialmente, otro estudio con una muestra heterogénea en edad y en condiciones de salud, encontró que los niveles elevados de IGF-1 se asociaron con el antecedente de enfermedad cardiovascular (ECV) en el sexo masculino, mientras que en el femenino, la asociación mostró un patrón curvilíneo (39). Sin embargo, otro trabajo con mujeres postmenopáusicas no demostró asociación entre el nivel sérico de IGF-1 o de IGFPB-3 con el riesgo de infarto (40).

Adicionalmente, con la administración de IGF-1 recombinante humana a diabéticos tipo 2 se ha podido demostrar su acción hipoglucemiante, el aumento de sensibilidad a la insulina, así como la disminución en el porcentaje de grasa corporal (6, 7) y en los niveles de triglicéridos y colesterol total (8, 16).

Conclusiones:

El sistema IGF-1 parece intervenir de forma importante en la homeostasis de la glucosa y en la fisiopatología de la diabetes tipo 2. Las concentraciones adecuadas de IGF-1 parecen mejorar los factores de riesgo y la fisiopatología de la enfermedad cardiovascular (ECV), sin embargo, los resultados son controversiales por lo cual se hace necesario más investigaciones prospectivas y experimentales para reconocer la verdadera influencia vasculoprotectora de este mediador en el diabético tipo 2.

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