Fig. 1.
TUNEL assay of preconditioned mesenchymal stem cells (MSC) following exposure to hypoxia. A: MSCs exposed only to normoxia without treatment (control). B: MSCs preconditioning with hyperoxia; (C) MSCs preconditioned with pan-caspase inhibitor (CI); and (D) MSCs preconditioned with the combination of hyperoxia and CI prior to hypoxia exposure. Preconditioning with hyperoxia, CI, or the combination resulted in a decrease in apoptosis as compared to (E) MSCs exposed to hypoxia without preconditioning. This is obvious by a decrease in green fluorescence which represents apoptotic MSCs. Nucleic DNA has been labeled by DAPI staining (blue fluorescence). F: The apoptotic score index determined by TUNEL assays for MSCs preconditioned with hyperoxia, CI or the combination are shown. P-values above columns represent comparison to control; NS, non- significant.