Fig. 6: Identification of miRs targeting Cox5a to suppress hypoxic cell death.

a Candidate miRs were identified using the TargetScan database. Expression of candidate miRs b in the hearts of control and MI rats and c H9c2 cells under normoxic and hypoxic conditions. The values are shown as normalized miR expression levels relative to U6 expression levels in triplicate samples. Changes in d the Cox5a transcript and e Cox5a protein expression levels induced by transfection of the candidate miRs were measured by qPCR analysis and immunoblot analysis, respectively. The qRT-PCR data are shown as the Cox5a expression level normalized to the Gapdh expression level in triplicate samples. Band intensities were measured as area densities and analyzed using ImageJ software. Relative intensity levels indicate the protein level normalized to the β-actin level. f Luciferase assay using the 3′UTR of Cox5a. g Changes in cell viability (left) and cytotoxicity (right) in H9c2 cells with Cox5a knockdown and miR treatment were determined by a WST-based cell viability assay and an LDH-based cytotoxicity assay, respectively. All data are representative of two independent experiments. Significant differences between groups were determined via ANOVA, with p values indicated as *p < 0.05 and **p < 0.01. CON control rat group, MI myocardial infarction rat group, N cells under normoxia, H12h cells exposed to hypoxia for 12 h, miRs-Neg negative control miRs, Cox5a KD Cox5a-knockdown cells.