miR-21 Reduces Hydrogen Peroxide-Induced Apoptosis in c-kit⁺ Cardiac Stem Cells In Vitro through PTEN/PI3K/Akt Signaling

Figure 2

miR-21 mimics and inhibitor’s effects on CSC apoptosis. (a) Cultured CSCs were treated with miR-21 mimics for 24, 48, or 72 h before miR-21 RT-PCR detection. miR-21 mimics significantly increased miR-21 but no difference was detected among the three time points. compared with control. in each group. (b) CSCs were incubated with miR-21 mimics, miR-21 inhibitor, or their scrambles for 48 h or challenged by 2 h incubation with 100 μM H₂O₂ at the same time. miR-21 mimics significantly increased miR-21 levels, while miR-21 inhibitor significantly decreased miR-21 levels in normal or H₂O₂ stress condition. compared with control; compared with H₂O₂ group; compared with miR-21 inhibitor group. in each group. (c) The apoptosis rate of c-kit⁺ CSCs treated with mimics for 48 h and/or 100 μM H₂O₂ for 2 h was measured using the Annexin V-FITC/PI staining assay. PI: propidium iodide. (d) The statistics of the states of CSCs in (c). compared with control; compared with H₂O₂ group.

(a)

(b)

(c)

(d)