OXIDATIVE STRESS AS SENECCENCE INDUCTOR FOR ADIPOSE-DERIVED MESENCHYMAL STROMAL CELLS

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