OBJECTIVE: To observe airway epithelial barrier dysfunction in acute respiratory distress syndrome (ARDS), and the possible regulatory role of p38 mitogen-activated protein kinase (p38MAPK). METHODS: The primary human trachea-bronchial epithelial cells were incubated either in 1 f.Lg/mL lipopolysaccharide (LPS) , I J.Lg/mLLPS + 10 nmol/L p38MAPK inhibitor (SB203580), or in control medium. Cells were harvested at 3, 6, 24 and 48 hours after incubation. The cell count, trans-epithelial electrical resistance (TER) , macromolecular permeability (fluorescence staining), and proteomics were measured at different time points. RESULTS: Compared with control group,the amount of airway epithelial cells in LPS group was significantly lowered at 24 hours and 48 hours [24 hours: (62.5 ± 12.0)% vs. (85.0 ± 15.0)% , 1'=-5.681, P=0.001 ; 48 hours: (67.5 ± 17.0)% vs. (79.0 ± 20.0)% , 1'=-4.260,P=0.00 1 J, TER was also significantly decreased at 3 hours and 48 hours (D/cm2 , 3 hours: 307 ± 108 vs. 376 ± 60,1'=-3.606, P=0.049; 48 hours: 290 ± 86 vs. 371 ± 43, 1'=6.971, P=0.037), and the macromolecular permeability was shown to he increased in LPS group [48 hours: (122.2 ± 22.0)% vs. (100.0 ± 18.0)%, 1'=3.182, P=0.036]; and phosphorylation-p38MAPK p-p38MAPK) was increased (relative intensity: 0.34 ± 0.16 vs. 0.28 ± 0.10,1'=4.303, P=0.029). However, SB203580 attenuated the damages induced by LPS both in the amount of epithelial cells [24 hours: (82.5±22.0)% vs. (62.5±25.0)%, 1'=-6.124, P=0.010; 48 hours: (79.5±28.0)% vs. (67.5 ± 16.0)% , 1'=-3.860, P=0.039 J, and TER of epithelial cells (Diem', 48 hours: 411 ± 118 vs. 290 ± 97,1'=3.560, P=0.022) . In addition, the down-regulation of expression of p-p38MAPK as induced hy LPS was significantly alleviate by SB203580 (relative intensity: 0.04 ±0.01 vs. 0.34 ±0.16, 1'=3.840; P=0.011). CONCLUSION: LPS induced airway epithelial barrier dysfunction in ARDS, and p38MAPK may be involved in the pathway of LPS induced airway epithelial barrier dysfunction.
OBJECTIVE: To observe airway epithelial barrier dysfunction in acute respiratory distress syndrome (ARDS), and the possible regulatory role of p38 mitogen-activated protein kinase (p38MAPK). METHODS: The primary human trachea-bronchial epithelial cells were incubated either in 1 f.Lg/mL lipopolysaccharide (LPS) , I J.Lg/mLLPS + 10 nmol/L p38MAPK inhibitor (SB203580), or in control medium. Cells were harvested at 3, 6, 24 and 48 hours after incubation. The cell count, trans-epithelial electrical resistance (TER) , macromolecular permeability (fluorescence staining), and proteomics were measured at different time points. RESULTS: Compared with control group,the amount of airway epithelial cells in LPS group was significantly lowered at 24 hours and 48 hours [24 hours: (62.5 ± 12.0)% vs. (85.0 ± 15.0)% , 1'=-5.681, P=0.001 ; 48 hours: (67.5 ± 17.0)% vs. (79.0 ± 20.0)% , 1'=-4.260,P=0.00 1 J, TER was also significantly decreased at 3 hours and 48 hours (D/cm2 , 3 hours: 307 ± 108 vs. 376 ± 60,1'=-3.606, P=0.049; 48 hours: 290 ± 86 vs. 371 ± 43, 1'=6.971, P=0.037), and the macromolecular permeability was shown to he increased in LPS group [48 hours: (122.2 ± 22.0)% vs. (100.0 ± 18.0)%, 1'=3.182, P=0.036]; and phosphorylation-p38MAPK p-p38MAPK) was increased (relative intensity: 0.34 ± 0.16 vs. 0.28 ± 0.10,1'=4.303, P=0.029). However, SB203580 attenuated the damages induced by LPS both in the amount of epithelial cells [24 hours: (82.5±22.0)% vs. (62.5±25.0)%, 1'=-6.124, P=0.010; 48 hours: (79.5±28.0)% vs. (67.5 ± 16.0)% , 1'=-3.860, P=0.039 J, and TER of epithelial cells (Diem', 48 hours: 411 ± 118 vs. 290 ± 97,1'=3.560, P=0.022) . In addition, the down-regulation of expression of p-p38MAPK as induced hy LPS was significantly alleviate by SB203580 (relative intensity: 0.04 ±0.01 vs. 0.34 ±0.16, 1'=3.840; P=0.011). CONCLUSION:LPS induced airway epithelial barrier dysfunction in ARDS, and p38MAPK may be involved in the pathway of LPS induced airway epithelial barrier dysfunction.