Effect of propofoi on LPS-induced TLR4 expression in rat alveolar type II epithelial cells

Objective To investigate the effect of propofol on LPS-induced TLR4 expression in rat alveolar type Ⅱ epithelial cells. Methods The primarily cultured alveolar type Ⅱ epithelial cells isolated from male rats were randomly assigned to one of 5 groups: group Ⅰ cells were incubated for 3 h without any additive (control) ; group Ⅱ cells were incubated with LPS 1 μg/ml for 3 h (LPS) ; group Ⅲ , Ⅳ , Ⅴ cells were incubated with LPS 1 μg/ml + propofol 25, 50 and 100 μmol/L respectively for 3 b (P1-3). TLR4 mRNA and TLR4 protein expression was detected by real time PCR and Western blot. TNF-α release amount was measured using ELISA. Results LPS significantly' increased TLR4 mRNA and protein expression in alveolar type Ⅱ epithelial cells as well as TNF-α release amount. Propefol at 50 and 100 μmol/L significantly inhibited LPS-imluced increase in TLR4 mRNA and protein expression and TNF-α release amount. Conclusion Propofol can dose-dependently inhibit LPS-induced inflammation in alveolar type Ⅱ epithelial ceils, through down-regnlation of TLR4 gene and protein expression. Key words: Propofol;  Toll-like receptor 4;  Epithelial cells;  Pulmonary alveoli;  Tumor necrosis factor-alpha