Mitochondrial glutamate dehydrogenase activity
The glutamate dehydrogenase (GDH) activity was measured using a commercial assay kit (Cat# K729, Biovision, CA, USA) according to the instruction of manufacturer. The lysates were mixed with reaction reagents and then the absorbance of each samples were detected at 450 nm. For calculation of GDH activity, these mixtures were incubated for 30 min and measured again the absorbance.