Research Paper Volume 10, Issue 11 pp 3327—3352

Oxidative muscles have better mitochondrial homeostasis than glycolytic muscles throughout life and maintain mitochondrial function during aging

Figure 5. Upon aging, the tibialis anterior and soleus undergo similar changes in mitochondrial biogenesis, fission/fusion, disposal and autophagy marker expression. Markers of mitochondrial biogenesis, fission/fusion, disposal and autophagy were evaluated in tibialis anterior (A, C) and soleus (B, D) muscles isolated from young (3 mo) and old (29 mo) mice. A-B) Representative OXPHOS subunits, PGC-1α, PGC-1β, Mfn2, short (S)- and long (L)-OPA1, LC3-II/I, and APG5 in whole muscle lysates were evaluated by Western blotting and normalized to Ponceau-stained total protein (see Figures S6, S7). The mean plus standard deviation of 3 technical replicates of lysates from 4-5 mice/group is shown; 3 mo (n=5), 29 mo (n=4). C-D) Mfn2, OPA1, and p62 levels in mitochondrial fractions were evaluated by Western blotting and normalized to Ponceau-stained total protein (see Figure S7). The mean plus standard deviation of lysates from 4 mice/group run on 2 separate gels is shown. *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, ****p ≤ 0.0001.