Adekunbi Daniel A, Huber Hillary F, Li Cun, Nathanielsz Peter W, Cox Laura A, Salmon Adam B
Department of Molecular Medicine and Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.
Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas, USA.
bioRxiv. 2024 Feb 9:2024.02.06.579010. doi: 10.1101/2024.02.06.579010.
Biological resilience, broadly defined as ability to recover from acute challenge and return to homeostasis, is of growing importance to the biology of aging. At the cellular level, there is variability across tissue types in resilience and these differences likely to contribute to tissue aging rate disparities. However, there are challenges in addressing these cell-type differences at regional, tissue and subject level. To address this question, we established primary cells from aged male and female baboons between 13.3-17.8 years spanning across different tissues, tissue regions, and cell types including: (1) fibroblasts from skin and from heart separated into left ventricle (LV), right ventricle (RV), left atrium (LA) and right atrium (RA), (2) astrocytes from the prefrontal cortex and hippocampus and (3) hepatocytes. Primary cells were characterized by their cell surface markers and their cellular respiration assessed with Seahorse XFe96. Cellular resilience was assessed by modifying a live-cell imaging approach we previously reported that monitors proliferation of dividing cells following response and recovery to oxidative (50µM-HO), metabolic (1mM-glucose) and proteostasis (0.1µM-thapsigargin) stress. We noted significant differences even among similar cell types that are dependent on tissue source and the diversity in cellular response is stressor specific. For example, astrocytes were more energetic and exhibited greater resilience to oxidative stress (OS) than both fibroblasts and hepatocytes. RV and RA fibroblasts were less resilient to OS compared with LV and LA respectively. Skin fibroblasts were less impacted by proteostasis stress compared to astrocytes and cardiac fibroblasts. Future studies will test the functional relationship of these outcomes to age and developmental status of donors as potential predictive markers.
生物弹性被广泛定义为从急性挑战中恢复并回归内稳态的能力，对衰老生物学的重要性日益凸显。在细胞水平上，不同组织类型的弹性存在差异，这些差异可能导致组织衰老速率的不同。然而，在区域、组织和个体层面解决这些细胞类型差异存在挑战。为解决这个问题，我们从13.3 - 17.8岁的老年雄性和雌性狒狒身上建立了原代细胞，涵盖不同组织、组织区域和细胞类型，包括：（1）来自皮肤和心脏的成纤维细胞，心脏的成纤维细胞又分为左心室（LV）、右心室（RV）、左心房（LA）和右心房（RA）；（2）来自前额叶皮质和海马体的星形胶质细胞；（3）肝细胞。通过细胞表面标志物对原代细胞进行表征，并用海马XFe96评估其细胞呼吸。通过改进我们之前报道的活细胞成像方法来评估细胞弹性，该方法监测分裂细胞在对氧化应激（50µM - HO）、代谢应激（1mM - 葡萄糖）和蛋白质稳态应激（0.1µM - 毒胡萝卜素）作出反应和恢复后的增殖情况。我们注意到，即使在相似的细胞类型中也存在显著差异，这些差异取决于组织来源，并且细胞反应的多样性是应激源特异性的。例如，星形胶质细胞比成纤维细胞和肝细胞更有活力，并且对氧化应激（OS）表现出更大的弹性。与LV和LA的成纤维细胞相比，RV和RA的成纤维细胞对OS的弹性较小。与星形胶质细胞和心脏成纤维细胞相比，皮肤成纤维细胞受蛋白质稳态应激的影响较小。未来的研究将测试这些结果与供体年龄和发育状态之间的功能关系，作为潜在的预测标志物。
