MFN2 and type 2 diabetes mellitus: In summary, this study showed that men with type 2 diabetes exhibited lower expression of muscle SOD1 and ETC complex V and higher expression of ETC complex IV, MFN2, DRP1, Na+/K+ α1, and α2 and NHE1 compared to nondiabetes counterparts matched for age and body composition, which was associated with a lower exercise capacity for the men with type 2 diabetes than the nondiabetes counterparts.