To investigate the mechanism of quercetin in promoting muscle regeneration in acute skeletal muscle injury.

Satellite cells were randomly divided into blank group (conventional culture), hydrogen peroxide (H₂O₂) group (100 μmol·L^-1 H₂O₂ treated cells for 24 h), quercetin group (10 μmol·L^-1 quercetin treated cells for 24 h), H₂O₂+quercetin group (100 μmol·L^-1 H₂O₂+10 μmol·L^-1 quercetin treated cells for 24 h). Cell proliferation was detected by cell counting kit-8 (CCK-8) method; protein expression was detected by Western blot assay; mitochondrial reactive oxygen species (ROS) levels and related indicators of mitochondrial respiration were detected by kit.

The 24 h proliferation rates of cells in blank group, quercetin group, H₂O₂ group and H₂O₂+quercetin group were (100.00±4.27)%, (148.79±13.17)%, (81.70±3.19)% and (120.83±8.81)%, respectively; the relative expression levels of superoxide dismutase 1 (SOD1) protein were 0.64±0.09, 0.76±0.09, 0.24±0.03 and 0.43±0.06, respectively; the relative expression levels of myosin heavy chain (MyHC) protein were 0.61±0.05, 0.67±0.06, 0.32±0.03 and 0.47±0.06, respectively; the fluorescence intensities of mitochondrial ROS were (52.56±1.97), (48.46±4.05), (119.53±13.06) and (102.91±8.93) a.u., respectively; the catalase (CAT) levels were (28.66±2.18), (35.62±3.89), (18.13±1.78) and (23.97±2.72) μmol·mg protein^-1, respectively; mitochondrial respiratory chain (MRC) complex Ⅰ levels were (19.77±1.01), (23.28±2.48), (9.87±1.01) and (14.19±0.75) μmol·mg protein^-1, respectively. The above indexes in quercetin group and H₂O₂ group were compared with blank group, the above indexes in H₂O₂+quercetin group were compared with H₂O₂ group, the difference was statistically significant (P<0.05, P<0.01, P<0.001).

Quercetin can promote mitochondrial respiration by clearing mitochondrial ROS levels, improve oxidative damage, and then promote satellite cell proliferation, which can promote muscle regeneration in acute skeletal muscle injury.