Oxidative Stress as Senescence Inductor for Adipose-Derived Mesenchymal Stromal Cells

The studies of tissue-specific mesenchymal stromal cells (MSCs) for medical purposes are inspired by their potential for multilineage differentiation, a broad spectrum of bioactive molecule secretion, and other properties. Cell senescence induced by oxidative stress can alter the morphofunctional characteristics of MSCs. The work was aimed at studying senescence-related morphofunctional changes in adipose-derived MSCs (AD-MSCs) under sublethal oxidative stress. The viability of cells 96 h after adding 500 μМ H2O2 was less than 5% (incubation time—6 h). The percentage of surviving cells in other samples was higher (>85%); however, the rate of cell growth decreased significantly. Treated AD-MSCs were larger in size and their cytoplasm was more granular. Active senescence-associated β-galactosidase was detected in nearly 100% of cells. These findings are evidence of the activation of senescence. The level of intracellular reactive oxygen species (ROS) was increased, as well as the activity of lysosomal and mitochondrial compartments. After one-hour oxidative stress, ROS returned to baseline values. An increase in endogenous ROS was observed 24–96 h post-stress.