白介素-1β在羊膜腔内注射脂多糖导致的新生鼠肺泡化阻滞中的作用

Effects of interleukin-1β on intra-amniotic lipopolysaccharide-induced alveolar arrest in neonatal rats

目的·探讨白介素-1β(IL-1β)在羊膜腔内注射脂多糖(LPS)导致的新生鼠肺泡化阻滞中的作用。方法·通过SD孕鼠羊膜腔内注射LPS建立新生鼠支气管肺发育不良(BPD)模型。孕鼠(孕19 d)随机分为生理盐水(Saline)组、LPS组和LPS+anti-IL-1β组。随机取出生1、3、7 d新生鼠肺组织,经苏木精-伊红(H-E)染色后观察病理学改变,并通过real-time PCR和ELISA检测肺组织中IL-1βmRNA及蛋白表达水平。培养大鼠骨髓源性原代巨噬细胞,给予LPS干预,经全转录组测序检测与IL-1β相关的多个基因的表达变化。结果·与Saline组相比,LPS组肺泡和次级突起数量减少,平均内衬间隔增大;肺组织IL-1βmRNA表达及蛋白表达量均明显增加。应用anti-IL-1β可改善LPS引起的新生鼠肺组织病理变化。LPS可导致Gbp5、Ccl3、Nod2、Ccr5、Mefv、Casp4、Ifnar1等基因表达明显上调,而Lgals9、Gstp1基因表达明显下调,其中Gbp5、Ccl3、Nod2、Ccr5、Casp4、Ifnar1、Lgals9可正向调节IL-1β表达。结论·在BPD模型中LPS通过上调巨噬细胞中IL-1β的表达,诱导新生鼠肺泡化阻滞。全转录组测序揭示LPS可以通过多种路径调控巨噬细胞中IL-1β的表达。

Objective · To investigate the effects of interleukin-1 β （IL-1β） on neonatal rat alveolar arrest induced by intra-amniotic injection of lipopolysaccharide （LPS）. Methods · A neonatal SD rat model of hronchopulmonary dysplasia （BPD） was constructed by intra-amniotic injection of LPS in pregnant rats. The pregnant rats （El9） were randomly assigned to Saline group, LPS group and LPS＋anti-IL-1β group. The lungs of the neonatal rats were randomly collected 1, 3 and 7 days after birth. Pathological changes in the lungs were observed by hematoxylin-eosin （H-E） staining, and expression of IL-1β mRNA and protein was detected by real-time PCR and ELISA, respectively. Rat bone marrow derived primary macrophage was cultured in vitro, and given LPS intervention, then genes related with IL-1β were detected through whole transcriptome sequencing. Results · Compared with the Saline group, the alveolar counts and secondary septa counts significantly decreased, and mean liner intercept significantly increased in LPS group. Moreover, the expression of IL-1β mRNA and protein in lungs significantly increased in LPS group. The LPS-induced pathological changes of lung tissues in neonatal rats were improved by anti-IL-1β. LPS could up-regulate the expression of genes including Gbp5, Ccl3, Nod2, Ccr5, Mefv, Casp4 and lfnarl, but down-regulate Lgals9 and Gstpl. Among these genes Gbp5, Cel3, Nod2, Ccr5, Casp4, Ifnarl and Lgals9 could positively regulate IL-1β production. Conclusion · LPS can induce alveolar arrest through up-regulating the expression of IL-1β in macrophages in neonatal rat BPD model. Whole transcriptome sequencing reveals that LPS can regulate the expression of IL-1β in macrophages through several paths.