When we assessed the levels of Myostatin (MSTN) in gastrocnemius and serum, we observed decreased levels of this anti-anabolic factor in e-RA, both locally (0.39 ± 0.05 e-RA vs. 1 ± 0.13 healthy, p < 0.0001) and systemically (503.7 ± 114.3 e-RA vs. 1103 ± 93.62 healthy, p < 0.05) (Figure 3B). This evidence concerns the gene MSTN and rheumatoid arthritis.