Research Paper Volume 1, Issue 9 pp 818—830

Figure 2. Chronic muscle use increases the expression of muscle and mitochondrial regulatory proteins in young and old animals. (A). Representative Western blots and graphical summary (B) of the effects of chronic contractile activity on the expression levels of proteins important for mitochondrial biogenesis (PGC-1α, Tfam), apoptotic signaling (AIF, HSP70), and aging (SIRT1), in muscles from young (closed bars) and old (open bars) animals expressed as the fold increase in chronically stimulated over control muscles (n = 6-11). (C) HSP70 protein content is shown separately due to the difference in scale, compared to the data in B. Data represent the mean ± SEM. * P < 0.05, stimulated vs. control.