Transglutaminase 2 Prevents Premature Senescence and Promotes Osteoblastic Differentiation of Mesenchymal Stem Cells through NRF2 Activation

Figure 2

MSCs with downregulated TG2 are prone to premature senescent induction but not oxidative stress-induced apoptosis during in vitro cell expansion. (a) Wild-type and TG2-knockdowned MSCs were treated with H₂O₂, tert-butylhydroperoxide (tBHP), and RAS-selective lethal 3 (RSL3) for 24 hr at indicated concentrations. Cell viability was evaluated by WST assay. (b) Wild-type and TG2-knockdowned MSCs were treated with tBHP (50 μM) for 24 hr and stained for SA-β-galactosidase. (c) The self-renewal capacity of wild-type and TG2-knockdowned MSCs was assessed by colony-forming unit (CFU) assay. Crystal violet-staining was performed on day 9. The pattern of colonies was observed with microscopy. The scale bar indicates 100 µm. Data is shown as the mean values ± SEM from three independent experiments, each with technical replicates. Statistical significance was tested by Student’s t test (n = 3; ; ).

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