Geltinger Florian, Holtze Susanne, Hildebrandt Thomas Bernd, Ochs Matthias, Brandenberger Christina
Institute of Functional Anatomy, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.
Am J Physiol Lung Cell Mol Physiol. 2025 Jul 1;329(1):L84-L96. doi: 10.1152/ajplung.00246.2024. Epub 2025 May 14.
Naked-mole rats (NMRs; ) exhibit unique biological traits such as resistance to cancer, exceptional longevity, and high tolerance to low-oxygen environments. However, little is known about the lung structure of this eusocial species. Here, the lungs of adult NMRs were qualitatively examined using light and electron microscopy, followed by structural quantification of the alveolar region by means of stereology. One queen (>18 years) was also included in the study. The data normalized to body weight (BW) were furthermore compared to that of young and old mice () as well as the expression of genes of surfactant proteins. Qualitatively, NMRs showed larger conducting airways compared to mice. Additionally, alveolar septa with a double-layered capillary network were observed in NMRs, indicating microvascular maturation and late alveolarization. Stereological analysis of the lung parenchyma revealed a lower septal surface area and alveolar epithelial type II (AEII) cell number per BW in NMRs compared to mice. However, in NMRs, the AEII cells were larger with a higher content of lamellar bodies, resulting in more intracellular surfactant per BW. Furthermore, the expression of surfactant protein B () was prominently higher in NMRs. The queen showed a larger mean alveolar volume, but no other age-related structural alterations were observed. The results indicate that NMRs are capable of late alveolarization, which is in line with their good regenerative potential. Additionally, NMRs have more intracellular surfactant and higher expression of , suggesting functional alterations in their surfactant system possibly as an environmental adaptation. Naked mole-rats (NMRs) can adapt to hypoxic environments and are the longest-living rodents. Comparison of their lung structure with that of mice revealed that NMRs have a reduced alveolar surface area per body weight but an increased pool of intracellular surfactant. Additionally, the septa of NMRs were thicker with an occasional double-layered capillary network. These features indicate a high regenerative potential with late alveolarization and environmental adaptation, even in old animals (>18 years).
裸鼹鼠表现出独特的生物学特性，如抗癌能力、超长寿命以及对低氧环境的高耐受性。然而，对于这种群居性物种的肺部结构却知之甚少。在此，利用光学显微镜和电子显微镜对成年裸鼹鼠的肺部进行了定性检查，随后通过体视学方法对肺泡区域进行了结构量化。研究中还纳入了一只年龄超过18岁的雌性首领裸鼹鼠。此外，将以体重（BW）标准化的数据与年轻和老年小鼠的数据以及表面活性蛋白基因的表达进行了比较。定性分析表明，与小鼠相比，裸鼹鼠的传导气道更大。此外，在裸鼹鼠中观察到具有双层毛细血管网络的肺泡隔，表明微血管成熟和晚期肺泡化。对肺实质的体视学分析显示，与小鼠相比，裸鼹鼠每单位体重的隔表面积和肺泡II型上皮（AEII）细胞数量更低。然而，在裸鼹鼠中，AEII细胞更大，板层小体含量更高，导致每单位体重的细胞内表面活性物质更多。此外，表面活性蛋白B在裸鼹鼠中的表达明显更高。雌性首领裸鼹鼠的平均肺泡体积更大，但未观察到其他与年龄相关的结构改变。结果表明，裸鼹鼠能够进行晚期肺泡化，这与其良好的再生潜力相符。此外，裸鼹鼠具有更多的细胞内表面活性物质和更高的表达，表明其表面活性物质系统可能发生了功能改变，这可能是一种环境适应性变化。裸鼹鼠能够适应低氧环境，是寿命最长的啮齿动物。将它们的肺部结构与小鼠的肺部结构进行比较发现，裸鼹鼠每单位体重的肺泡表面积减少，但细胞内表面活性物质储备增加。此外，裸鼹鼠的肺泡隔更厚，偶尔会有双层毛细血管网络。这些特征表明，即使是老年动物（>18岁），裸鼹鼠也具有晚期肺泡化和环境适应性的高再生潜力。
