Suppr超能文献

铁调素/铁转运蛋白调节系统破坏的小鼠肺脏中气血屏障增厚及Ⅱ型肺泡上皮细胞改变。

Air-blood barrier thickening and alterations of alveolar epithelial type 2 cells in mouse lungs with disrupted hepcidin/ferroportin regulatory system.

作者信息

Mühlfeld Christian, Neves Joana, Brandenberger Christina, Hegermann Jan, Wrede Christoph, Altamura Sandro, Muckenthaler Martina U

机构信息

Institute of Functional and Applied Anatomy, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.

Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany.

出版信息

Histochem Cell Biol. 2019 Mar;151(3):217-228. doi: 10.1007/s00418-018-1737-y. Epub 2018 Oct 3.

Abstract

Iron accumulates in the lungs of patients with common respiratory diseases or transfusion-dependent beta-thalassemia. Based on our previous work, we hypothesized that systemic iron overload affects the alveolar region of the lung and in particular the surfactant producing alveolar epithelial type II (AE2) cells. Mice with a point mutation in the iron exporter ferroportin, a model for human hemochromatosis type 4 were compared to wildtype mice (n = 5 each). Lungs were fixed and prepared for light and electron microscopy (EM) according to state-of-the-art protocols to detect subcellular iron localization by scanning EM/EDX and to perform design-based stereology. Iron was detected as electron dense particles in membrane-bound organelles, likely lysosomes, in AE1 cells. AE2 cells were higher in number but had a lower mean volume in mutated mice. Lamellar body volume per AE2 cell was lower but total volume of lamellar bodies in the lung was comparable to wildtype mice. While the volume of alveoli was lower in mutated mice, the volume of alveolar ducts as well as the surface area, volume and the mean thickness and composition of the septa was similar in both genotypes. The thickness of the air-blood barrier was greater in the mutated than in the WT mice. In conclusion, disruption of systemic iron homeostasis affects the ultrastructure of interalveolar septa which is characterized by membrane-bound iron storage in AE1 cells, thickening of the air-blood barrier and hyperplasia and hypotrophy of AE2 cells despite normal total intracellular surfactant pools. The functional relevance of these findings requires further analysis to better understand the impact of iron on intra-alveolar surfactant function.

摘要

铁在患有常见呼吸系统疾病的患者或依赖输血的β地中海贫血患者的肺部蓄积。基于我们之前的研究工作,我们推测全身铁过载会影响肺部的肺泡区域,尤其是影响产生表面活性剂的肺泡II型上皮(AE2)细胞。将铁输出蛋白(一种人类4型血色素沉着症模型)发生点突变的小鼠与野生型小鼠进行比较(每组n = 5只)。按照最新方案对肺进行固定,制备用于光学显微镜和电子显微镜(EM)观察的样本,通过扫描电子显微镜/能谱仪(EM/EDX)检测亚细胞铁定位,并进行基于设计的体视学分析。在AE1细胞中,铁被检测为膜结合细胞器(可能是溶酶体)中的电子致密颗粒。突变小鼠的AE2细胞数量较多,但平均体积较小。每个AE2细胞的板层小体体积较小,但肺中板层小体的总体积与野生型小鼠相当。虽然突变小鼠的肺泡体积较小,但两种基因型的肺泡管体积以及表面积、体积、间隔的平均厚度和组成相似。突变小鼠的气血屏障厚度大于野生型小鼠。总之,全身铁稳态的破坏会影响肺泡间隔的超微结构,其特征是AE1细胞中存在膜结合铁储存、气血屏障增厚以及AE2细胞增生和萎缩,尽管细胞内表面活性剂总量正常。这些发现的功能相关性需要进一步分析,以更好地理解铁对肺泡内表面活性剂功能的影响。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验