Nanotube topography rejuvenates the senescence of mesenchymal stem cells by activating YAP signalling

Abstract

Improving the regenerative ability of senescent stem cells is a critical issue in combating aging. The destiny and function of senescent stem cells are controlled by the niche, including the physical architecture of the surface of the extracellular matrix (ECM). In this study, we explored the functions of TiO₂ nanotube topography on mesenchymal stem cells (MSCs) under senescence, as well as its mechanical effects on senescence. First, we created different nanotube topographies on the titanium samples. Next, we cultured senescent mesenchymal stem cells (S-MSCs) on samples with various nanotube topographies to determine suitable parameters. We found nanotube with a diameter of 10 nm significantly alleviated the cellular senescence of S-MSCs and improved the osteogenic differentiation of S-MSCs in vitro. Using an ectopic periodontium regeneration model, we confirmed that specific nanotube topography could promote tissue regeneration of S-MSCs in vivo. Moreover, we demonstrated that nanotube topography activated YAP in S-MSCs and reformed nuclear-cytoskeletal morphology to inhibit senescence. Taken together, our study establishes a bridge linking between nano-topography, mechanics, and senescence, suggesting a potential strategy to improve tissue regeneration in aged individuals by providing optimized surface topography on biomaterials.