Fig. 4.

Follistatin increases muscle mass in SOD1^G93A mice. AAV–follistatin or AAV–GFP at 1 × 10¹¹ viral genomes was injected into the hindlimbs (quadriceps and tibialis muscles) of SOD1^G93A mice at 40 days of age (n = 15 per group). (A) Representative photograph of end-stage (126 days) SOD1^G93A showing the widespread increase in muscle mass in AAV–follistatin-treated animals. (B) Wet weights of tibialis anterior, gastrocnemius, medial quadriceps, and triceps muscle from AAV–follistatin- and AAV–GFP-treated animals (n = 10–15 per group, average ± SE). (C) ELISA for follistatin in blood from AAV–GFP- and AAV–follistatin-treated animals (age, 100 day; n = 8 average ± SE).