Glutathione reductase assay kit

The Caspase 9 Activity Assay Kit (Beyotime, China, Cat. No: C1158) was used to measure the activity of caspase-9 according to the manufacturer’s instructions. The concentrations of GSH, SOD and GPX were evaluated using commercial kits (Cellular Glutathione Peroxidase Assay Kit, Beyotime, China, Cat. No: S0056; Glutathione Reductase Assay Kit, Beyotime, China, Cat. No: S0055; Total Superoxide Dismutase Assay Kit, Beyotime, China, Cat. No: S0101, respectively). ATP production was measured using a luciferase-based ATP assay kit (Beyotime Institute of Biotechnology) with a microplate reader [44 (link)].

Content of malondialdehyde (MDA), the final product of lipid peroxidation, was measured as described by Du and Bramlage (1992) (link). ${\mathrm{O}}_{\mathrm{2}}^{\mathrm{•}\mathrm{-}}$ release rate was assayed following hydroxylamine method (Elstner and Heupel, 1976 (link)), and H₂O₂ content was determined according to the method of Sui et al. (2007) (link). Activities of superoxide dismutase (SOD; EC 1.15.1.1) and catalase (CAT; EC1.11.1.6) were measured according to our previous methods (Tan et al., 2008 (link)). Activities of ascorbate peroxidase (APX; EC 1.11.1.11), dehydroascorbate reductase (DHAR; EC 1.8.5.1) and monodehydroascorbate reductase (MDHAR; EC 1.6.5.4) were assayed by the method of Fryer et al. (1998) (link). Activities of glutathione peroxidase (GPX; EC 1.11.1.7) and glutathione reductase (GR; EC 1.6.4.2) were measured using Total Glutathione Peroxidase Assay Kit and Glutathione Reductase Assay Kit from Beyotime institute of Biotechnology (Shanghai, China), respectively. The contents of reduced ascorbate (AsA) and reduced glutathione (GSH) were measured as described by Gossett et al. (1994) (link). The content of soluble protein was measured by the method of Bradford (1976) (link).