2.11. Measurement of intracellular reactive oxygen species (ROS) level

The intracellular ROS level was measured using the fluorescent oxidant‐sensitive probe 2′7‐dichlorofluorescenin diacetate (DCFDA; Invitrogen). After myotube formation, 20 μM DCFDA was added to the culture and incubated for 30 min at 37°C. The ROS signals (green fluorescence) were detected with a Keyence BZ X‐810 fluorescence microscope. As a positive control, 0.5 mM H₂O₂ was added to the culture and incubated for 30 min at 37°C.