Mitochondrial Enzyme Activity Assay

Approximately 1 mL of mitochondrial extract was introduced to a population of 5 × 10⁶ cells. The sample underwent ice-cold homogenization using either a homogenizer or mortar. Subsequently, the mixture was centrifuged at 4 °C and 600× g for 10 min.
Mitochondrial complex I (NADH-Q reductase) (BC0510, Solarbio, Beijing, China), II (FADH2-Q reductase) (BC3230, Solarbio, Beijing, China), III (cytochrome reductase) (BC3240, Solarbio, Beijing, China), IV (cytochrome oxidase) (BC0940, Solarbio, Beijing, China), V (adenosine triphosphate (ATP) synthase) (BC1440, Solarbio, Beijing, China) activities, and ATP content (BC0300, Solarbio, Beijing, China), were measured using their respective analytical kits according to the manufacturer’s protocols [58 (link),59 (link),60 (link)].