Relationship between TLR4/NF-κB signaling pathway and propofol-induced inhibition of endotoxin-induced release of TNF-α from alveolar macrophages of rats / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the relationship between Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway and propofol-induced inhibition of endotoxin-induced release of tumor necrosis factor-alpha (TNF-α) from alveolar macrophages (AMs) of rats.Methods AMs extracted from adult male Sprague-Dawley rats were cultured and inoculated in 6-well plates (1 × 106 cells/well)and in 96-well plates (1×104 cells/well).The cells were divided into 5 groups (n=18 each) using a random number tablecontrol group (group C),dimethyl sulfoxide group (group D),lipopolysaccharide (LPS) group (group L),propofol group (group P) and LPS plus propofol group (group L+P).The cells were continuously cultured with phosphate buffer solution in group C.Dimethyl sulfoxide was added at the final concentration of 5 mg/ml in group D.LPS was added at the final concentration of 1 μg/ml in group L.Propofol was added at the final concentration of 25 μmol/L (4.46 μg/ml) in group P.LPS and propofol were added at the final concentration of 1 μg/ml and 25 μmol/L (4.46 μg/ml),respectively,in group L+P.At 24 h of culture or incubation,the cell viability was detected by CCK-8 assay,the morphological changes of cells were observed using Wright's staining,the concentration of TNF-α in the supernatant was determined by enzyme-linked immunosorbent assay,and TLR4 expression and NF-κB activities were measured by Western blot.Results Compared with group C,the cell viability and concentration of TNF-α in the supernatant were significantly increased,the expression of TLR4 was up-regulated,and the activity of NF-κB was enhanced in L and L+P groups (P＜0.05),and no significant change was found in the parameters mentioned above in D and P groups (P＞0.05).Compared with group L,the cell viability and concentration of TNF-α in the supernatant were significantly decreased,the expression of TLR4 was down-regulated,and the activity of NF-κB was weakened (P＜0.05),the morphological changes of cells were significantly attenuated,and the number of pseudopodia was reduced in group L+P.Conclusion The mechanism by which propofol inhibits endotoxin-induced release of TNF-α from AMs is related to inhibited activation of TLR4/NF-λB signaling pathway in rats.