p38 siRNA reduced lung ischemia-reperfusion injury of pulmonary microvascular endothelium after lung transplantation through NF-κB pathway inhibition / 中华器官移植杂志

ABSTRACT

Objective Using small interfering RNA (siRNA) against p38 and simulated lung transplantation model,we discussed the effect of p38 siRNA on hypoxia/reoxygenation injury of pulmonary microvascular endothelial cells (PMVECs) after lung transplantation.Methods We transfected the PMVECs with p38 siRNA or non-targeting (NT) siRNA.After 48 h,these cells were exposed to simulated ischemia-reperfusion.At 2 h and 4 h of reperfusion,we detected lactate dehydrofenase (LDH) leakage rate,malondialdehyde (MDA) levels,superoxide dismutase (SOD) activity,cell apoptosis,and the serum levels of interleukin (IL)-1,IL-6 and tumor necrosis factor (TNF)-α.Protein levels of p38,NF-κB and AP-1 were detected.Untreated PMVECs served as the negative control.Results As compared with NT siRNA,p38 siRNA reduced LDH leakage rate (22.3 ± 5.7 vs.45.1 ± 6.2 and 46.3 ± 7.3 vs.75.6 ± 12.4),decreased MDA levels (4.1 ± 2.2 vs.7.1 ± 2.1 and 3.9 ± 0.5 vs.6.1 ± 1.2),increased SOD activity (12.8 ± 3.2 vs.9.4 ± 1.1 and 10.8 ± 1.2 vs.7.0 ± 1.1),and inhibited apoptosis (2.8 ± 0.6 vs.4.1 ± 1.4 and 3.1 ± 1.1 vs.5.8 ± 1.3).p38 siRNA reduced the levels of IL-1 (288 ± 89 vs.592 ± 95 and 380 ± 94 vs.775 ± 175) and IL-6 (38 ± 5 vs.70 ± 12 and 80 ± 20 vs.118-± 17),however,had no influence on TNF-α level.Silencing p38 gene decreased phosphorylation of p65 and inhibitor of nuclear factor kappa-B kinase β,and increased inhibitor of nuclear factor kappa-B expression.However,p38 siRNA had no effect on the phosphorylation of c-Jun and c-Fos.Conclusion Through inhibiting the NF-κB classic activation pathway,p38 siRNA reduced oxidative stress,inflammation and apoptosis of rat PMVECs,protected membrane integrity,and reduced hypoxia/reoxygenation injury.