Cell apoptosis and death analysis
Flow cytometry (Beckman Coulter, Fullerton, California, USA) is used to distinguish the apoptotic period and quantity through different periods of apoptosis and different membrane permeability to dyes. In order to detect the apoptosis rate of the drug, the A549 cell density was adjusted to 2 × 105 cells / well in a 6-well plate, and the next day was exposed to final concentrations of 0, 5, 10, 20, and 40 μM NCTD. According to the manufacturer’s protocol, Annexin V-FITC / PI (Becton Dickinson, USA) was used to perform the operation. The translocation of phosphatidy lserine to the cell surface is an indicator of early apoptotic cells. Therefore, Annexin V-positive and PI-negative cells were identified as apoptotic. Cell Quest software (FCM, Becton Dickinson, USA) was used to determine the apoptotic rate.