Syed Mansoor A, Choo-Wing Rayman, Homer Robert J, Bhandari Vineet
Division of Perinatal Medicine, Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8064, United States of America.
Department of Pathology, Yale University School of Medicine, 310 Cedar Street, New Haven, CT 06520, United States of America.
PLoS One. 2016 Jan 22;11(1):e0147588. doi: 10.1371/journal.pone.0147588. eCollection 2016.
The role of vascular endothelial growth factor (VEGF)-induced 3 different nitric oxide synthase (NOS) isoforms in lung development and injury in the newborn (NB) lung are not known. We hypothesized that VEGF-induced specific NOS pathways are critical regulators of lung development and injury.
We studied NB wild type (WT), lung epithelial cell-targeted VEGF165 doxycycline-inducible overexpressing transgenic (VEGFTG), VEGFTG treated with a NOS1 inhibitor (L-NIO), VEGFTG x NOS2-/- and VEGFTG x NOS3+/- mice in room air (RA) for 7 postnatal (PN) days. Lung morphometry (chord length), vascular markers (Ang1, Ang2, Notch2, vWF, CD31 and VE-cadherin), cell proliferation (Ki67), vascular permeability, injury and oxidative stress markers (hemosiderin, nitrotyrosine and 8-OHdG) were evaluated.
VEGF overexpression in RA led to increased chord length and vascular markers at PN7, which were significantly decreased to control values in VEGFTG x NOS2-/- and VEGFTG x NOS3+/- lungs. However, we found no noticeable effect on chord length and vascular markers in the VEGFTG / NOS1 inhibited group. In the NB VEGFTG mouse model, we found VEGF-induced vascular permeability in the NB murine lung was partially dependent on NOS2 and NOS3-signaling pathways. In addition, the inhibition of NOS2 and NOS3 resulted in a significant decrease in VEGF-induced hemosiderin, nitrotyrosine- and 8-OHdG positive cells at PN7. NOS1 inhibition had no significant effect.
Our data showed that the complete absence of NOS2 and partial deficiency of NOS3 confers protection against VEGF-induced pathologic lung vascular and alveolar developmental changes, as well as injury markers. Inhibition of NOS1 does not have any modulating role on VEGF-induced changes in the NB lung. Overall, our data suggests that there is a significant differential regulation in the NOS-mediated effects of VEGF overexpression in the developing mouse lung.
血管内皮生长因子（VEGF）诱导的3种不同一氧化氮合酶（NOS）亚型在新生（NB）肺的发育和损伤中的作用尚不清楚。我们推测VEGF诱导的特定NOS途径是肺发育和损伤的关键调节因子。
我们研究了NB野生型（WT）、肺上皮细胞靶向VEGF165强力霉素诱导过表达转基因（VEGFTG）、用NOS1抑制剂（L-NIO）处理的VEGFTG、VEGFTG×NOS2-/-和VEGFTG×NOS3+/-小鼠，使其在室内空气（RA）中出生后（PN）7天。评估肺形态学（弦长）、血管标志物（Ang1、Ang2、Notch2、vWF、CD31和VE-钙黏蛋白）、细胞增殖（Ki67）、血管通透性、损伤和氧化应激标志物（含铁血黄素、硝基酪氨酸和8-羟基脱氧鸟苷）。
RA中VEGF过表达导致PN7时弦长和血管标志物增加，在VEGFTG×NOS2-/-和VEGFTG×NOS3+/-肺中显著降至对照值。然而，我们发现VEGFTG/NOS1抑制组对弦长和血管标志物没有明显影响。在NB VEGFTG小鼠模型中，我们发现VEGF诱导的NB鼠肺血管通透性部分依赖于NOS2和NOS3信号通路。此外，抑制NOS2和NOS3导致PN7时VEGF诱导的含铁血黄素、硝基酪氨酸和8-羟基脱氧鸟苷阳性细胞显著减少。抑制NOS1没有显著影响。
我们的数据表明，NOS2的完全缺失和NOS3的部分缺陷可防止VEGF诱导的病理性肺血管和肺泡发育变化以及损伤标志物。抑制NOS1对VEGF诱导的NB肺变化没有任何调节作用。总体而言，我们的数据表明，在发育中的小鼠肺中，VEGF过表达的NOS介导效应存在显著差异调节。
