Figure 2.

(a) Original recording of the assessment of the respiratory chain function in myoblasts. Myoblasts were incubated in Mitomed medium at 25°C in the presence of 50 μg/mL saponin. Further additions: ADP 1 mM, Rot: 10 μM rotenone, Succ: 10 mM succinate, Atr: 0.1 mM atractyloside, Ant: 10 μM antimycin A, TMPD+Asc: 0.5 mM TMPD with 2 mM ascorbate, and NaN₃: 5 mM sodium azide. (b, c) Summary of results shown in (a) in groups of cells cultured from young subjects. Complex I: ADP-dependent complex I activity, complex II: ADP-dependent complex II activity, complex IV: complex IV activity, and (d, e) citrate synthase activities in myoblast samples assessed in panel (b). Data are mean ± SEM. ^∗ p < 0.05 differences compared to passage 2. P2: passage 2; P6: passage 6.