Figure 2.

Hydrogen sulfide ameliorates oxidative stress and improves mitochondrial biogenesis in neonatal mouse cardiomyocytes. Neonatal mouse cardiomyocytes were pretreated in free-serum medium with 100 μmol/L NaHS for 12 h. Consequently, cells were washed twice with PBS and were recovered for 24 h by changing into FBS-MEM, followed by exposure to free-serum medium without or with 600 μmol/L H₂O₂ for another 4 h. (a) ROS levels were tested by flow cytometry (*P < 0.01 vs. Con, ^†P < 0.05 vs. vehicle). (b) Mitochondrial DNA copy number was tested by quantitative polymerase chain reaction (*P < 0.001 vs. Con, ^†P < 0.05 vs. vehicle).(c) Sod2 protein expression level is determined using Western blot analysis (*P < 0.05 vs. Con, ^†P < 0.01 vs. vehicle). The data shown are mean ± SE of three independent experiments. PBS: Phosphate-buffered saline; FBS: Fetal bovine serum; MEM: Modified Eagle's medium; ROS: Reactive oxygen species; Con: Control; SE: Standard error; NaHS: Sodium hydrosulfide; Sod2: Superoxide dismutase.