Effects of Downregulation of MicroRNA-181a on H₂O₂-Induced H9c2 Cell Apoptosis via the Mitochondrial Apoptotic Pathway

Figure 4

Effects of the down- or upregulation of miR-181a on H₂O₂-induced H9c2 cell morphology and cellular injury. H9c2 cardiomyocytes were treated with miRNAs for 6 h prior to H₂O₂ (400 μM, 2 h) treatment. (a) H9c2 cells were transfected with miR-CTL, miR-181a (50 nM), anti-CTL, or anti-miR-181a (100 nM) for 6 h, followed by real-time PCR analysis of the miR-181a expression levels 24 h later. *𝑃<0.01 versus miR-CTL; ^&𝑃<0.01 versus anti-CTL group; the values represent the mean ± SEM; 𝑛=3. (b) The downregulation of miR-181a restored the oxidative stress-induced alteration of H9c2 cell morphology, whereas the upregulation of miR-181a exacerbated the morphological changes. Scale bar: 25 μm. (c) The cellular MDA levels were measured using the TBA method, and the concentration of MDA was expressed as nmol/mg protein. *𝑃<0.01 versus control (CTL); ^&𝑃<0.01 versus miR-CTL; ^#𝑃<0.01 versus anti-CTL group; the values represent the mean ± SEM; 𝑛=5. (d) The LDH activity in the culture medium was measured, and the results are expressed as U/L. ^∗𝑃<0.01 versus control (CTL); ^&𝑃<0.01 versus miR-CTL; ^#𝑃<0.01 versus anti-CTL group; the values represent the mean ± SEM; 𝑛=5.

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