Regulation of IGF‐I, IGFBP‐4 and IGFBP‐5 gene expression by loading in mouse skeletal muscle

FEBS Letters

Lebacq, Jean²  Thissen, Jean-Paul¹  Awede, Bonaventure²  Gailly, Phillipe² 

[1] Unité de Diabétologie et de Nutrition, Université Catholique de Louvain, 1200 Brussels, Belgium;Unité de Physiologie Générale des Muscles, Université Catholique de Louvain, 1200 Brussels, Belgium

关键词: Loading;    Hypertrophy;    IGFBP;    Phenotype change;    Skeletal muscle;    IGF;    insulin-like growth factor;    IGFBP;    insulin-like growth factor binding protein;    EDL;    extensor digitorum longus;    CTR;    control;    OLD;    overloaded;    ULD;    unloaded;   

DOI  :  10.1016/S0014-5793(99)01469-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Gene expression of IGF-I, IGFBP-4 and IGFBP-5 was studied in hindhimb skeletal muscle of mice, which were either overloaded or unloaded for 8 days. Overloading induced a 15% hypertrophy in soleus muscle associated with a 60% increase of IGF-I transcript levels and a doubling of IGFBP-4 mRNA levels. IGFBP-5 mRNA levels were decreased to one third of the control value. Changes in IGFBPs mRNA always preceded changes in IGF-I gene expression. Unloading by hindlimb suspension resulted in atrophy of soleus muscle (20%) and phenotype change towards the fast type associated with a transient decrease of IGF-I mRNA (30%) and a sustained increase (×2) of IGFBP-5 transcript. These alterations in IGFBPs expression, in unloaded or overloaded soleus, suggest that they may play a role in skeletal muscle adaptation to changes in loading.

【 授权许可】

Unknown