SIRT3 Enhances Mesenchymal Stem Cell Longevity and Differentiation

Figure 5

SIRT3 overexpression restores differentiation and reduces oxidative stress in aged MSCs. (a) SIRT3 was overexpressed in later-passage (passage 7) MSCs compared to untreated later-passage MSCs and early-passage (passage 1) MSCs and subsequently assessed by western blotting. VEC: empty vector control. Alpha tubulin served as a loading control. (b) Differentiation was assessed 21 days after the treatment with appropriate induction media. Adipocytes were stained with oil red O, and osteoblasts were stained with alizarin red S. Scale . (c) Oil red O and alizarin red S were eluted with isopropanol; then, absorbance was read at 500 nm or 520 nm, respectively. (d) Senescence was assessed by quantifying the percentage of cells with β-galactosidase activity. Bars represent means ± SEM for the 3 MSC strains for 3 technical replicates of 1 MSC strain. “Untreated” cells were not transfected. (e) MSCs were stained with DHE, which was detected by flow cytometry. Bars represent average DHE values (median channel fluorescence from FL3) ± SEM from the 3 MSC strains. Cells treated with NAC, an ROS scavenger, served as a negative control. from two-sided t-tests.

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