Table 2.

Relationship of IGF-1 expression and downstream signaling molecule phosphorylation to indexes of muscle size and function

	MHC Protein Content	Leg Muscle Mass	Knee Extensor Isometric Torque
IGF-1	−0.104	−0.495	−0.198
phospho-Akt/Akt	0.602*	−0.01	0.020
phospho-mTOR/mTOR	0.481	0.136	0.535†
phospho-GSK-3β/GSK-3β	−0.477	0.248	−0.036
phospho-eIF2Bε/eIF2Bε	−0.10	−0.320	−0.370
phospho-eIF4E-BP/eIF4E-BP	0.02	0.053	0.184
phospho-p70 S6K/p70 S6K	0.26	−0.151	0.312

Data represent Pearson correlation coefficients. Correlation coefficients for knee extensor isometric torque reflect partial correlation coefficients after the effect of leg muscle mass was statistically removed. Sample sizes for IGF-1 mRNA and signaling molecules are provided in Figs. 1–3. For myosin heavy chain (MHC) protein content, data were not available on 1 female HF patient. mTOR, mammalian target of rapamycin; GSK-3β, glycogen synthase kinase-3β; eIF4E-BP, eukaryotic translation initiation factor 4E binding protein-1; p70 S6K, p70 ribosomal S6 kinase.

^*P < 0.02,

^†P < 0.05.