Identification of a novel non-flavonoid senolytic agent from natural resources targeting oncogene- and DNA damage-induced senescence

Senolytics represent a promising therapeutic strategy for age-related diseases by selectively eliminating senescent cells. In this study, we screened a library of 101 extracts derived from natural resources indigenous to Jeju Island to identify potential senotherapeutics. We evaluated their senolytic activity using two distinct models of cellular senescence: Oncogene-Induced Senescence (OIS) in human diploid fibroblasts and DNA Damage-Induced Senescence (DIS) in A549 lung cancer cells. Through this screening, we identified a specific extract that exhibited significant selective cytotoxicity against senescent cells while sparing proliferating cells. Following bioassay-guided fractionation, we isolated an active compound, designated as ACE. Interestingly, ACE-induced cell death was significantly attenuated by pretreatment with Z-VAD (a pan-caspase inhibitor) and Necrostatin-1, suggesting that ACE exerts its senolytic effect via regulated cell death pathways, primarily apoptosis. Flow cytometry and Western blot analyses confirmed that ACE treatment significantly reduced Senescence-Associated beta-galactosidase (SA-beta-gal) activity and downregulated key senescence markers, including p16, p21, and p53, in a dose- and time-dependent manner. Mechanistically, ACE activated the p38 MAPK signaling pathway, leading to the accumulation of reactive oxygen species (ROS). Notably, chemical analysis revealed that ACE is a non-flavonoid compound. Collectively, these findings suggest that ACE is a novel senolytic candidate derived from Jeju natural resources with potential clinical applications.