CDC5L facilitates cardiomyocyte proliferation and ameliorates myocardial ischemia-reperfusion injury via modulation of the FGF10-YAP axis.

Myocardial infarction (MI) causes irreversible cardiomyocyte loss, creating a need for cardiac repair therapies. The role of cell division cycle 5-like (CDC5L), a cell cycle regulator, in cardiac repair is unknown. This study aims to define the role of CDC5L in mitigating ischemia-reperfusion (I/R) injury by assessing its impact on cardiomyocyte proliferation and apoptosis and to determine the mechanism involving the FGF10-YAP axis. We model cardiac injury using in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) in neonatal mouse cardiomyocytes and in vivo I/R in adult mice. To investigate CDC5L function, we modulate its expression via adenoviral or AAV9-mediated overexpression or knockdown. Proliferation markers (EdU (+), Ki67 (+), pH3 (+)), apoptosis (TUNEL staining, Bax/Bcl-2 ratio), and cardiac function (echocardiography) are assessed. Through transcriptomic screening, we identify CDC5L downstream targets and validate their functional roles using FGF10 knockdown rescue assays. We find that CDC5L is upregulated in the post-I/R murine myocardium. Its overexpression enhances cardiomyocyte proliferation, preserves cardiac function, reduces apoptosis, and diminishes infarct size. Transcriptomic analysis identifies FGF10 as a key downstream effector, and we confirm that CDC5L upregulates FGF10 expression. Notably, FGF10 knockdown reverses the proliferative and anti-apoptotic effects of CDC5L. Moreover, the CDC5L-mediated reduction in YAP phosphorylation is also dependent on FGF10, as this effect is abolished upon FGF10 knockdown. In conclusion, CDC5L attenuates cardiac I/R injury by promoting cardiomyocyte proliferation and inhibiting apoptosis through the FGF10-YAP pathway. This CDC5L-FGF10-YAP axis represents a promising therapeutic target to improve myocardial regeneration and recovery after myocardial infarction.