[Effect of glucose regulated protein 78 gene silencing on hyperoxia-induced apoptosis in alveolar epithelial cells].

Objective: To investigate the effect and possible mechanism of small interfering RNA (siRNA)-mediated glucose regulated protein 78 (GRP78) gene silencing on hyperoxia-induced apoptosis of alveolar epithelial cells.

Methods: Human lung adenocarcinoma A549 cells in vitro were transfected with siRNA by Lipofectamine(TM)2000. Cells were divided into untransfected group, scrambled siRNA group and GRP78-siRNA group. A model of hyperoxia-induced cell injury was established by 95% oxygen. After 48 hours, the mRNA and protein levels of GRP78 and C/EBP homologous protein (CHOP) were detected respectively by real-time PCR and Western blotting, and cell apoptosis was measured by flow cytometry.

Results: By GRP78 siRNA interference, the mRNA and protein levels of GRP78 decreased significantly, while CHOP increased significantly. The apoptosis rate of A549 cells was elevated significantly.

Conclusion: GRP78 gene silencing may enhance the CHOP apoptotic pathway and promote apoptosis in alveolar epithelial cells induced by hyperoxia, suggesting the potential value of GRP78 as a therapeutic target for the clinical treatment of bronchopulmonary dysplasia.