Departments of Surgery, Division of Pediatric Surgery, Pediatrics & Child Health and Physiology & Pathophysiology (Adjunct), University of Manitoba and Children's Hospital Research Institute of Manitoba, Biology of Breathing Theme, Winnipeg, Manitoba, Canada.
Life and Health Sciences Research Institute/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
Ann Surg. 2019 May;269(5):979-987. doi: 10.1097/SLA.0000000000002595.
We aimed to evaluate the use of miR-200b as a prenatal transplacental therapy in the nitrofen rat model of abnormal lung development and congenital diaphragmatic hernia (CDH).
Pulmonary hypoplasia (PH) and pulmonary hypertension determine mortality and morbidity in CDH babies. There is no safe medical prenatal treatment available. We previously discovered that higher miR-200b is associated with better survival in CDH babies. Here, we investigate the role of miR-200b in the nitrofen rat model of PH and CDH and evaluate its use as an in vivo prenatal therapy.
We profiled miR-200b expression during nitrofen-induced PH using RT-qPCR and in situ hybridization in the nitrofen rat model of PH and CDH. The effects of nitrofen on downstream miR-200b targets were studied in bronchial lung epithelial cells using a SMAD luciferase assay, Western blotting and Immunohistochemistry. We evaluated miR-200b as a lung growth promoting therapy ex vivo and in vivo using lung explant culture and transplacental prenatal therapy in the nitrofen rat model.
We show that late lung hypoplasia in CDH is associated with (compensatory) upregulation of miR-200b in less hypoplastic lungs. Increasing miR-200b abundance with mimics early after nitrofen treatment decreases SMAD-driven TGF-β signaling and rescues lung hypoplasia both in vitro and in vivo. Also, prenatal miR-200b therapy decreases the observed incidence of CDH.
Our data indicate that miR-200b improves PH and decreases the incidence of CDH. Future studies will further exploit this newly discovered prenatal therapy for lung hypoplasia and CDH.
我们旨在评估 miR-200b 作为产前胎盘治疗在异常肺发育和先天性膈疝（CDH）的硝基酚大鼠模型中的应用。
肺发育不全（PH）和肺动脉高压决定了 CDH 婴儿的死亡率和发病率。目前尚无安全的医学产前治疗方法。我们之前发现，miR-200b 水平较高与 CDH 婴儿的存活率更高有关。在这里，我们研究了 miR-200b 在硝基酚诱导的 PH 和 CDH 大鼠模型中的作用，并评估了其作为体内产前治疗的用途。
我们使用 RT-qPCR 和原位杂交技术在 PH 和 CDH 的硝基酚大鼠模型中对 miR-200b 的表达进行了分析。使用 SMAD 荧光素酶测定、Western blot 和免疫组织化学研究了硝基酚对支气管肺上皮细胞中 miR-200b 下游靶基因的影响。我们使用肺组织培养和硝基酚大鼠模型中的胎盘产前治疗评估了 miR-200b 作为促进肺生长的治疗方法的体外和体内效果。
我们表明，CDH 中的晚期肺发育不全与（代偿性）较少发育不全的肺中 miR-200b 的上调有关。在硝基酚处理后早期增加 mimics 的 miR-200b 丰度可降低 SMAD 驱动的 TGF-β信号传导，并在体外和体内均挽救肺发育不全。此外，产前 miR-200b 治疗可降低 CDH 的发生率。
我们的数据表明，miR-200b 可改善 PH 并降低 CDH 的发生率。未来的研究将进一步探索这种新发现的产前治疗肺发育不全和 CDH 的方法。
