Early apoptosis induced by mechanical stretch in human alveolar type Ⅱ epithelial cells / 上海第二医科大学学报

ABSTRACT

Objective To investigate the apoptosis response to mechanical stretch in human alveolar type Ⅱ epithelial cells A549.Methods First,A549 cells were given different stretch(0%,5%,15%,30%) at frequency of 0.5 Hz for 4 h.Then,A549 cells were stretched for different periods(0 h,2 h,4 h,8 h) at stretch 15%,0.5 Hz.Last,A549 cells were stretched for different frequency(0 Hz,0.2 Hz,0.5 Hz and 1 Hz) at stretch 15% for 4 h.The early apoptosis was detected by flow cytometry. Results A549 cells submitted to cyclic stretch caused the early apoptosis in a time-,stretch-and frequency-dependent manner.In details,at 0.5 Hz and 4 h stretch-dependence occurred,at 15% stretch and 0.5 Hz time-dependence occurred,and at 15% stretch and 4 h frequency-dependence occurred. Conclusion Mechanical stretch can induce the early apoptosis in human alveolar type Ⅱ epithelial cells A549,which may be one of the mechanisms of ventilator-induced lung injury.