Neri Francesco, Zheng Shuyuan, Watson Mark A, Desprez Pierre-Yves, Gerencser Akos A, Campisi Judith, Wirtz Denis, Wu Pei-Hsun, Schilling Birgit
Buck Institute for Research on Aging, Novato, CA 94945 , USA.
USC Leonard Davis School of Gerontology, Los Angeles, CA 90089, USA.
Aging (Albany NY). 2025 Aug 7;17(8):2063-2078. doi: 10.18632/aging.206299.
Cellular senescence has been strongly linked to aging and age-related diseases. It is well established that the phenotype of senescent cells is highly heterogeneous and influenced by their cell type and senescence-inducing stimulus. Recent single-cell RNA-sequencing studies identified heterogeneity within senescent cell populations. However, proof of functional differences between such subpopulations is lacking. To identify functionally distinct senescent cell subpopulations, we employed high-content image analysis to measure senescence marker expression in primary human endothelial cells and fibroblasts. We found that G2-arrested senescent cells feature higher senescence marker expression than G1-arrested senescent cells. To investigate functional differences, we compared IL-6 secretion and response to ABT263 senolytic treatment in G1 and G2 senescent cells. We determined that G2-arrested senescent cells secrete more IL-6 and are more sensitive to ABT263 than G1-arrested cells. We hypothesize that cell cycle dependent DNA content is a key contributor to the heterogeneity within senescent cell populations. This study demonstrates the existence of functionally distinct senescent subpopulations even in culture. This data provides the first evidence of selective cell response to senolytic treatment among senescent cell subpopulations. Overall, this study emphasizes the importance of considering the senescent cell heterogeneity in the development of future senolytic therapies.
细胞衰老与衰老及衰老相关疾病密切相关。衰老细胞的表型高度异质性且受其细胞类型和衰老诱导刺激的影响，这一点已得到充分证实。最近的单细胞RNA测序研究确定了衰老细胞群体内部的异质性。然而，缺乏此类亚群之间功能差异的证据。为了识别功能上不同的衰老细胞亚群，我们采用高内涵图像分析来测量原代人内皮细胞和成纤维细胞中衰老标志物的表达。我们发现，G2期停滞的衰老细胞比G1期停滞的衰老细胞具有更高的衰老标志物表达。为了研究功能差异，我们比较了G1期和G2期衰老细胞中白细胞介素-6（IL-6）的分泌情况以及对ABT263衰老溶解疗法的反应。我们确定，G2期停滞的衰老细胞比G1期停滞的细胞分泌更多的IL-6，并且对ABT263更敏感。我们推测细胞周期依赖性DNA含量是衰老细胞群体异质性的关键因素。这项研究证明了即使在培养中也存在功能上不同的衰老亚群。该数据首次证明了衰老细胞亚群对衰老溶解疗法存在选择性细胞反应。总体而言，这项研究强调了在未来衰老溶解疗法开发中考虑衰老细胞异质性的重要性。
