Role of phospholipid transfer protein in cigarette smoke-induced apoptosis of RLE-6TN cells / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the role of phospholipid transfer protein (PLTP) in cigarette smoke extract (CSE)-induced apoptosis of rat alveolar type II cells (RLE-6TN) in vitro.</p><p><b>METHODS</b>Rat alveolar epithelial cell line RLE-6TN were transfected with a small interfering RNA (siRNA) targeting PLTP prior to exposure to different concentrations of CSE for 24 or 48 h. The morphological changes of the apoptotic cells were observed by fluorescence microscopy with Hochest staining, and the cell apoptosis rate was measured with flow cytometry. The expression level of PLTP and caspase-3 activity in the cells were examined with Western blotting.</p><p><b>RESULTS</b>Exposure to CSE significantly increased the cell apoptosis rate from (1.68∓0.098)% to (18.663∓0.964)% (P<0.001). Hoechst staining revealed distinct apoptotic changes in CSE-treated cells, which showed increased PLTP expression and caspase-3 activity. PLTP knockdown with the specific siRNA partly suppressed the SCE-induced enhancement of caspase-3 activity in the cells.</p><p><b>CONCLUSION</b>PLTP may play a role in CSE-induced apoptosis of rat alveolar cells in vitro.</p>