Figure 1.

The IGF-1 axis is altered in the spinal cords of severe SMA-like mice. A, In situ hybridization on Igf-1r mRNA for the localization of expression in the lumbar spinal cords (L1–L5) of untrained control and type 2 SMA-like mice (left) compared with trained control and type 2 SMA-like mice (right) at 12 d of age (n = 4). Scale bar, 100 μm. B, Quantification by real-time qRT-PCR of Igf-1r transcripts normalized by 18S transcripts in the ventral lumbar spinal cords of untrained control and type 2 SMA-like mice compared with trained control and type 2 SMA-like mice at 12 d of age (n = 10). C–E, Western blot analysis (C) and quantification of IGF-1Rβ (D) and SMN (E) protein expression in the ventral lumbar spinal cords of untrained control and type 2 SMA-like mice compared with trained control and type 2 SMA-like mice at 12 d of age (n = 4). F, Quantification of circulating IGF-1 concentration by ELISA in the serum of untrained control and type 2 SMA-like mice compared with trained control and type 2 SMA-like mice at 12 d of age (n = 4). G, Schematic representation of the crossings yielding to Igf-1r^+/− SMA mice. H, Quantification by real time qRT-PCR of Igf-1r transcripts normalized by 18S transcripts in the ventral lumbar spinal cords of Igf-1r^+/+ and Igf-1r^+/− control mice compared with Igf-1r^+/+ and Igf-1r^+/− SMA mice at 12 d of age (n = 10). I, J, Western blot analysis (I) and quantification (J) of IGF-1Rβ protein expression in the ventral lumbar spinal cords of Igf-1r^+/+ and Igf-1r^+/− control mice compared with Igf-1r^+/+ and Igf-1r^+/− SMA mice at 12 d of age (n = 5). K, Quantification of circulating IGF-1 concentration by ELISA in the serum of IGF-1R^+/+ and IGF-1R^+/− control mice compared with Igf-1r^+/+ and Igf-1r^+/− SMA mice at 12 d of age (n = 4). Data are represented as mean ± SEM and significance is reported versus untrained or Igf-1r^+/+ control mice, respectively (*p < 0.05, **p < 0.01, ***p < 0.001).