Caspase expression and activity are selectively upregulated in atrophic muscle of SOD1G93A mice at paralysis stage. (A) Representative Western blot analysis using caspase-3 antibody (top) and cleaved caspase-3 antibody (bottom) in wild-type (WT) (lane 1), myosin light chain (MLC)/SOD1G93A (lane 2) and SOD1G93A (lane 4) transgenic muscle. Cnt+ represents the positive control (HeLa cells treated with staurosporin) for cleaved caspase-3. Immunoblotting for α-tubulin served as a control for protein loading. (B and C) Analysis (n = 5) of (B) caspase-1 and (C)caspase-3 activity on WT, MLC/SOD1G93A and SOD1G93A transgenic mice. *P < 0.05. Mean values ± SEM for caspase-1: WT = 1.055 ± 0.03, MLC/SOD1G93A = 0.908 ± 0.10 and SOD1G93A = 2.385 ± 0.10. Mean values ± SEM for caspase-3: WT = 1.01 ± 0.01, MLC/SOD1G93A = 0.75 ± 0.18 and SOD1G93A = 1.56 ± 0.07.