Silybin Mitigates Post-Myocardial Infarction Heart Failure in Mice via Modulation of HIF-1α-Driven Glycolysis and Energy Metabolism.

BACKGROUND

Post-myocardial infarction (MI) heart failure (HF) is characterized by myocardial energy metabolism disorder, with excessive glycolysis playing a key role in its progression. Silybin (SIL), a flavonoid derived from Silybum marianum, has demonstrated hepatoprotective and metabolic regulatory effects. However, the role of this flavonoid in ameliorating post-myocardial infarction heart failure (post-MI HF) by modulating energy metabolism remains unclear.

METHODS

This study employed an oxygen-glucose deprivation (OGD) model to induce myocardial cell injury in vitro, with YC-1 treatment used to inhibit hypoxia-inducible factor-1α (HIF-1α) for mechanistic validation. A myocardial infarction-induced HF mouse model was used for in vivo experiments.

RESULTS

In vitro, SIL enhanced cell viability, increased ATP levels, and decreased lactate production and reactive oxygen species (ROS) accumulation in OGD-treated myocardial cells. SIL downregulated the mRNA and protein expression of HIF-1α, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), glucose transporter 1 (GLUT1), and lactate dehydrogenase A (LDHA) while inhibiting HIF-1α nuclear translocation. Furthermore, SIL suppressed glycolytic proteins (PFKFB3, GLUT1, and LDHA) in a manner comparable to the HIF-1α inhibitor YC-1. This confirms that SIL's inhibition of glycolysis is HIF-1α-dependent. In vivo, SIL treatment improved cardiac function parameters (LVEF and LVFS) and attenuated left ventricular remodeling (LVID;d and LVID;s) in post-MI HF mice. Additionally, myocardial fibrosis markers were significantly reduced, accompanied by a decrease in the myocardial mRNA and protein expression of glycolytic proteins, including HIF-1α, PFKFB3, GLUT1, and LDHA.

CONCLUSIONS

Silybin effectively ameliorates post-myocardial infarction heart failure through the HIF-1α-mediated regulation of glycolysis, leading to improved myocardial energy metabolism and enhanced cardiac function.