重组人Elafin对慢性高氧诱导新生小鼠支气管肺发育不良中炎性因子及NF-κB信号通路的影响

Effects of recombinant human elafin on the expression of inflammatory factors and NF-κB p65 protein in neonatal mice with bronchopulmonary dysplasia induced by chronic hyperoxia

摘要:

目的：探讨重组人Elafin对慢性高氧致新生小鼠支气管肺发育不良（bronchopulmonary dysplasia，BPD）中炎性因子和核因子-κB p65（nuclear factor-κB，NF-κB）蛋白的影响。方法：将30只C57BL/6J新生24 h内小鼠随机分成空气组、高氧+L/R组及高氧+Elafin组（n=10）。高氧+L/R 组、高氧+Elafin组暴露于85%氧气中。21 d时进行基础肺功能测定，采用HE染色观察小鼠肺组织形态学改变，RT-PCR检测肺组织炎症因子的表达，Western blot检测NF-κB p65蛋白表达情况。结果：与空气组[（7.85±0.24） g]比较，高氧+L/R组小鼠体质量[（5.33±0.63） g]显著下降（P=0.000），肺发育受阻；TNF-α mRNA、IL-1β mRNA （P=0.000） 和NF-κB p65蛋白（P=0.001）表达增加，抗炎因子IL-4、IL-13 mRNA（P=0.000）表达降低。与高氧+L/R组比较，高氧+Elafin组小鼠体质量升高（P=0.014），肺泡形态趋于正常；TNF-α（P=0.011）、IL-1β（P=0.000） mRNA和NF-κB p65蛋白（P=0.001）表达降低，IL-4（P=0.047）、IL-13（P=0.000） mRNA表达增加。结论：Elafin能有效减轻高氧诱导的小鼠肺损伤，其作用机制可能与抑制NF-κB活化及炎症因子释放密切相关。

Abstract:

Objective：To investigate the effects of recombinant human elafin on the expression of inflammatory factors and nuclear factor-κB（NF-κB） p65 protein in neonatal mice with bronchopulmonary dysplasia（BPD） induced by chronic hyperoxia. Methods：A total of 30 C57BL/6J neonatal mice within postnatal 24 hours were equally and randomly divided into three groups：air group，hyper－oxia+Lactated-Ringer（L/R）-treated group（O2+L/R group，L/R solution as vehicle），and hyperoxia+elafin-treated group（O2+elafin group）. The O2+L/R group and the O2 +elafin group were exposed to 85% oxygen，while the air group was exposed to 21% oxygen（room air）. At 21 days of treatment，the baseline lung function was determined；HE staining was used to observe the morphological changes of the lung tissue；the mRNA expression of inflammatory factors was determined by real-time polymerase chain reaction and the expression of NF-κB p65 protein was determined by Western blot. Results：Compared with the air group，the O2+L/R group had a significantly lower body weight[（7.85±0.24） g vs. （5.33±0.63） g，P=0.000）] and delayed lung development；in addition，the O2+L/R group had significantly higher expression of tumor necrosis factor-α（TNF-α） mRNA（P=0.000），interleukin-1β（IL-1β） mRNA（P=0.000），and NF-κB p65 protein（P=0.001），but significantly lower expression of interleukin-4（IL-4） mRNA（P=0.000） and inter－leukin-13（IL-13） mRNA（P=0.000）. Compared with the O2+L/R group，the O2+elafin group had a significantly higher body weight（P=0.014） and relatively normal alveolar morphology；in addition，the O2+elafin group had significantly lower expression of TNF-α mRNA（P=0.011），IL-1β mRNA（P=0.000），and NF-κB p65 protein（P=0.001），but significantly higher expression of IL-4 mRNA（P=0.047） and IL-13 mRNA（P=0.000）. Conclusion：Elafin can effectively alleviate hyperoxia-induced lung injury in mice. The mechanism of action may be related to the inhibition of NF-κB activation and the release of inflammatory factors.