Fig. 7: Validation of the expression and interaction of Cox5a and miR-26a/b-5p in primary cardiomyocytes.

a Cox5a protein levels in primary cardiomyocytes under normoxic and hypoxic conditions. b Changes in cell viability (left) and cytotoxicity (right) in primary cardiomyocytes with Cox5a knockdown under normoxic and hypoxic stress. c Cox5a knockdown-induced expression of cell death-related factors. d Expression of miR-26a/b-5p in primary cardiomyocytes under normoxic and hypoxic conditions. e Changes in Cox5a transcript (left) and Cox5a protein (right) expression induced by miR-26a/b-5p treatment. f Luciferase assay using the 3′UTR of Cox5a. The qRT-PCR data are shown as the Cox5a and miR-26a/b-5p expression levels normalized to the Gapdh and U6 transcript levels, respectively, 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. Immunoblot experiments were performed twice independently. Significant differences between groups were determined via ANOVA, with p values indicated as *p < 0.05 and **p < 0.01. N cells under normoxia, H12h cells exposed to hypoxia for 12 h, NC negative control cells, KD Cox5a-knockdown cells, miRs-Neg negative control miRs.