The effect of a sol–gel derived silica coating doped with vitamin E on oxidative stress and senescence of human adipose-derived mesenchymal stem cells (AMSCs)
Abstract
Nowadays, a major medical problem concerns the effective treatment of musculoskeletal disorders, especially in elderly patients. Implantable metallic materials have been widely applied in reconstructive medicine, including the field of orthopedics. Many studies have presented the beneficial effects of sol–gel-derived silica coatings in the preparation of bioactive materials, e.g. drug-eluting or mesoporous materials that stimulate tissue regeneration. In the current research, we have fabricated a sol–gel-derived silica coating functionalized with vitamin E for the reduction of oxidative stress (OS) on adipose-derived mesenchymal stem cells (AMSCs) isolated from elderly patients. Elevated levels of endogenous OS, through the mitochondrial secretion of reactive oxygen species (ROS) has an unquestionable impact on the viability and multipotent character of MSCs, which in consequence leads to the decreased therapeutic potential of engrafted cells. In the present study, we used a common antioxidant (vitamin E) and investigated its influence on AMSC proliferation and apoptosis at a concentration of 2% in a functionalized sol. The morphologies of the surfaces and coatings were determined using scanning electron microscopy (SEM), and their elemental composition was determined by SEM-EDX. The immobilization of ascorbic acid in the coatings was confirmed with Raman spectroscopy. Using RT-PCR and multiple cell imaging techniques, we evaluated the influence of the novel biomaterial on AMSCs. We have found that the biomaterial functionalized with vitamin E has a beneficial effect on cell viability and proliferative potential, as it decreased OS and induced the activity of free radical scavengers e.g. SOD in AMSCs.