Effect of STAT3 on expression of surfactant proteins in alveolar epithelial cells line A549 / 国际儿科学杂志

ABSTRACT

Objective To investigate the role of signal transducer and activator of transcription 3 (STAT3) on the expression of surfactant proteins (SP) in alveolar epithelial cells line A549.Methods STAT3 overexpression lentivirus vector was constructed and transfected into A549 cells.Three small interfering RNAs (siRNA) were chemically synthesized and transfected into A549 cells by Lipofectamine 3000 to construct cells that silenced STAT3.The expression of STAT3,SP-A,SP-B,SP-C and SP-D were detected by Real-time PCR and Western blot.Results In A549 cells,over-or under-regulation of STAT3 were constructed successfully.When STAT3 was rendered over-expressed,the expression of SP-A,SP-B,SP-C,SP-D mRNA was significantly increased compared with Mock group(P ＜ 0.05).The proteins were found to be significantly increased as well.By contrast,when STAT3 was under-expressed,SP was down-regulated (P ＜ 0.05).Conclusion STAT3 regulates the expression of pulmonary surfactant proteins in A549 cells.Over-expression of the STAT3 gene promotes the expression of SP,and its under-expression inhibited it.