Tert-Butyl Hydroperoxide in Human Adult Mesenchymal Stem Cells Isolated from Dermis: A Stress-Induced Premature Senescence Model

Stem cell (SC)-based therapy exploits the ability of cells to migrate to damaged tissues and repair them. In this context, there is a strong interest in the use of mesenchymal stem cells (MSCs), multipotent SCs that are easy to obtain and are able to differentiate into various cell lineages. However, MSCs undergo cellular senescence during in vitro expansion, and may also become senescent in vivo, influenced by multiple molecular, cellular, and environmental interactions. Therefore, the development of in vitro cell models is crucial to study the mechanisms underlying senescence in MSCs. This study aimed to investigate the effects of tert-butyl hydroperoxide (t-BHP) as a senescence inducer in human dermal MSCs (hDMSCs), a promising tool for tissue repair. t-BHP induced a pro-senescent effect on hDMSCs greater than hydrogen peroxide (H₂O₂), as evidenced by ROS production, DNA damage, cell cycle arrest, inhibition of cell proliferation, changes in cellular and nuclear morphology, and cytoskeletal reorganization, as well as the increase in other senescence markers, including senescence-associated β-galactosidase (SA-β-Gal)-positive cells, and senescence-associated secretory phenotype (SASP). These results indicate that t-BHP could be a promising compound for inducing stress-induced premature senescence (SIPS) in hDMSCs, providing a valuable tool to investigate this process and evaluate the efficacy of senolytic compounds.