Riboflavin as a circadian modulator mitigates D-galactose-induced muscle senescence via oxidative stress and mitochondrial regulation in C2C12 cells

Skeletal muscle aging is characterized by impaired myogenic differentiation, mitochondrial dysfunction, and circadian rhythm disruption, which contribute to sarcopenia and muscle atrophy. This study investigated the effects of riboflavin, a precursor of FAD and FMN, on circadian rhythm regulation, a crucial cofactor in mitochondrial redox metabolism, and mitochondrial function in the D-galactose-induced aging C2C12. D-galactose treatment impaired myotube formation, whereas Ribo 20 μM restored myotube formation and myotube width. Ribo restored the circadian oscillations of differentiation-related genes and core clock genes that were reduced by D-galactose. Ribo alleviated oxidative stress by regulating ROS, MDA, catalase, and GPx levels. Ribo improved mitochondrial function by increasing ATP production and mitochondrial membrane potential. Notably, Ribo restored ATP5A rhythmicity, highlighting its role in the circadian regulation of mitochondrial function. Riboflavin is a promising candidate for age-related muscle decline, as it restores myogenic differentiation, reduces oxidative stress, and supports mitochondrial function, preserving circadian homeostasis.