Figure 1. Blockade of TNFα by Etanercept inhibited sarcopenia during spontaneous aging. Measurement of cross-sectional area (CSA) (A) and fiber size distribution (B) in GS of 12 months old mice and in control (saline) or Etanercept-treated mice at 22 and 28 months of age. *=p<0.05, **= p<0.01 and *** =p<0.001. (C) Representative histochemical images of GS muscle sections analyzed in 12 months old mice and in control or Etanercept-treated mice at 22 and 28 months of age. Scale bar=50 μm (magnification of the16x) (D). MRI measurement of muscle volume for control or Etanercept-treated mice at 12, 19 and 22 months of age. *=p<0.05 in comparison to 12 months of age (E) Body weight of control and Etanercept-treated mice monitored between 16 and 28 months of age. ** =p<0.01 vs 16 months of age, °= p<0.05 vs weight of control mice measured at the same time point. Data are show as mean ± standard error.