Background: Heart failure (HF) is a global pandemic which affects about 26 million people. PFKM (Phosphofructokinase, Muscle), catalyzing the phosphorylation of fructose-6-phosphate, plays a very important role in cardiovascular diseases. However, the effect of PFKM in glycolysis and HF remains to be elucidated.
Materials and methods: H9c2 rat cardiomyocyte cells were used in this study. Cells were treated with doxorubicin (DOX) to establish injury models. Cell viability was measured using CCK-8 kits. Apoptosis was estimated by TdT-mediated dUTP Nick-End Labeling (TUNEL) staining. Levels of lactate and ATP were measured using commercial kits. Extracellular acidification rate (ECAR) and Oxygen consumption rate (OCR) were determined using an XFe24 Extracellular Flux Analyzer. Chromatin immunoprecipitation (ChIP) assays were used to study the interaction between H3K27ac or histone deacetylase 1 (HDAC1) and the PFKM promoter region. Phosphoglycerate kinase 1 (PGK1) was either silenced or overexpressed to study its role. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunoblotting were used for gene expression.
Results: DOX treatment significantly inhibited PFKM expression in H9c2 cells. Overexpression of PFKM inhibited DOX-induced cell apoptosis and DOX-decreased glycolysis and oxidative phosphorylation, while silencing PFKM promoted cell apoptosis and inhibited glycolysis and oxidative phosphorylation in H9c2 cells. Moreover, PFKM regulated DOX-mediated cell viability and apoptosis through glycolysis pathway. Mechanism study showed that HDAC1 inhibited H3K27ac-induced transcription of PFKM in DOX-treated cells and regulated glycolysis.
Conclusion: PFKM could inhibit DOX-induced cardiotoxicity by enhancing oxidative phosphorylation and glycolysis, which might benefit us in developing novel therapeutics for prevention or treatment of HF.