Metabolism-related gene PDK1 regulates myocardial cell remodeling and its mechanism.

BACKGROUND

The progression of ischemic heart disease results from various forms of cardiomyopathies, which begin with cardiac remodelling. Pyruvate Dehydrogenase Kinase 1 (PDK1) is one of the basic kinase family components responsible for oxidative phosphorylation. However, due to the lack of a suitable research model, there is no evidence that remodelling pathogenesis in humans causes death by PDK1 knockout (KO). In the current study, we established a PDK1-deficient human cardiomyocyte (CM) model under conditions imitating the human PDK1-KO model. We determined the role of PDK1 in myocardial apoptosis induced by hypoxia and its implicit mechanism.

METHODS

A human PDK1-KO CM's model was established by combining CRISPR/Cas-9 gene-editing and human induced pluripotent stem cells (hiPSC) directed differentiation technology. The pathological features of PDK1-KO cardiomyocytes were assessed using a phenotypic cell model under basal and hypoxic conditions.

RESULTS

We found that pluripotency and differentiation efficiency of hiPSCs after PDK1 knockout remain intact. Cardiomyocytes with a PDK1 gene knockout showed hypoxia-induced myocardial apoptosis by disturbing mitochondrial metabolism, increased oxidative stress levels, and decreased cell energy and viability. In addition, lentivirus transfection significantly improved the metabolism and cell viability in PDK1-deficient cardiomyocytes.

CONCLUSIONS

Our study established a PDK1 knockout model under hypoxia that exhibits mitochondrial metabolism dysregulation, elevated oxidative stress, and decreased cell viability. This model is an important tool for understanding the mechanism of hypoxia-induced myocardial apoptosis, elucidating the gene-phenotype relationship of PDK1 deficiency, and providing evidence to mitigate the damage against hypoxia.