Figure 1

Characterization of mitochondrial metabolism differences in both cloned and uncloned satellite cells. (A) Freshly isolated SCs dissociated from single myofibers and seeded on gelatin-coated slides showed at immunofluorescence expression of satellite cell markers Pax7, Myf5 and MyoD (scale bar: 100 μm). (B) Time zero analysis: in 5 out of 5 preliminary experiments, after 24 hours of culture in muscle proliferating medium, SCs presented a different mitochondrial membrane potential ΔΨ_m (***p < 0.001). (C) Measurement of NaDH level: HPC and LPC demonstrated significant different redox states. These data confirmed that HPC has a glycolytic metabolism compared to low proliferative clones (*p < 0.05). (D) Measurement of CO₂ after incubation of D-glucose U-C₁₃ for 4 hours, in SC clones derived from fast and slow-twitch muscle fibers. Treated cells produced a higher amount of CO₂ compared to untreated control cells (**p<0.01, ***p < 0.001). Furthermore, HPC showed higher CO₂ production in respect to LPC, independently from the muscle type origin (***p < 0.001).