Facscalibur flow meter

Following the instructions, cell cycle and apoptosis detection kit (Beyotime, China) were used for cell cycle and apoptosis measurement. For cell cycle detection, cells were then re-suspended in PI staining solution for 30 min at 37 °C. For apoptosis detection, cells were stained with 5 μM Annexin V-FITC at 4 °C for 15 min, fixed in 70% ethanol overnight at 4 °C and then washed by PBS. The cells were then re-suspended in PI staining solution for 30 min at 37 °C. FACSCalibur flow meter with CellQuest software 3.2 (BD Biosciences) was used for data analysis.

Determination kits for malondialdehyde (MDA), glutathione (GSH) content, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-PX) were purchased from Nanjing Jiancheng Bioengineering Institute. The other suppliers are DMEM high glucose medium (HyClone); P/S antibiotic (HyClone); fetal bovine serum (Hangzhou Tianhang Biotechnology Co., Ltd.); trypsin EDTA (Jinuo Biomedical Technology Co., Ltd.); Cell Counting Kit-8 (CCK8), cell proliferation detection kit (Biosharp); reactive oxygen species (ROS) detection kit (Beyotime); Annexin V-FITC/PI apoptosis detection kit (Tianjin Sanjian Biotechnology Co., Ltd.); a UVA lamp purchased from Philips Lighting (China) Investment Co., Ltd. (the lamp power is 9W and the spectral wave is 364–366 nm); Dr-200bs enzyme labeling detector (Diatek); FACSCalibur flow meter (BD); Sco6we CO₂ constant temperature incubator (Shell Lab); Cx-21 ordinary optical microscope (Olympus); and a Tgl-16 freezing centrifuge (Instrument of Hunan Xiangyi Laboratory).