Doxorubicin-induced damage to AC16 cardiomyocytes and attenuation by human pericardial fluid Sca-1+/Nanog+ cells conditioned medium: a pilot study.

BACKGROUND: Heart failure (HF) remains a leading cause of death worldwide. Stem cells represent a promising strategy for myocardial regeneration due to their differentiation potential and paracrine effects. This study investigated the effect of human pericardial fluid Sca-1+/Nanog+ cells Conditioned Medium (hPFCs-CM) on doxorubicin (DOX)-induced damage to AC16 cardiomyocytes using transcriptomic analysis. METHODS: Human AC16 cardiomyocytes were divided into Control (CON), DOX, DOXh, and hPFCs groups. Cell viability, cytotoxicity (LDH release), reactive oxygen species (ROS) levels, and apoptosis were assessed. Transcriptomic sequencing was performed on CON, DOX, and DOXh groups. MYH3 and IFI16 genes were knocked down using siRNA, followed by Western blot analysis of apoptosis. RESULTS: DOX significantly increased ROS and apoptosis compared with CON group (P < 0.05), while hPFCs-CM attenuated these effects (P < 0.05). RNA-seq identified 52 differentially expressed genes between DOX and DOXh groups (adjP < 0.05). Three target genes (MYH3, IFI16, and KCTD14) were selected for RT-qPCR validation. Further functional assays revealed that MYH3 knockdown significantly potentiated the anti-apoptotic activity of hPFCs-CM (P < 0.05), whereas IFI16 knockdown showed no significant effect. CONCLUSION: hPFCs-CM effectively attenuated DOX-induced AC16 cardiomyocyte damage through MYH3, providing potential molecular targets for future mechanistic studies in myocardial injury treatment.