Introduction:

Myocardial ischemia-reperfusion (I/R) injury is one of the mechanisms contributing to the high mortality rate of acute myocardial infarction.

Purpose:

This study intended to study the role of naringin in cardiac I/R injury.

Methods:

AC16 cells (human cardiomyocyte cell line) were subjected to oxygen-glucose deprivation/recovery (OGD/R) treatment and/or naringin pretreatment. Then, the apoptosis was examined by flow cytometry and Western blotting. The concentration of IL-6, IL-8 and TNF-α was measured by enzyme-linked immunosorbent assay (ELISA) kits. How naringin influenced microRNA expression was examined by microarrays and quantitative real-time polymerase chain reaction (qRT-PCR). Dual luciferase reporter assay was employed to evaluate the interaction between miR-126 and GSK-3β. The GSK-3β/β-catenin signaling pathway was examined by Western blotting. Finally, rat myocardial I/R model was created to examine the effects of naringin in vivo.

Results:

Naringin pretreatment significantly decreased the cytokine release and apoptosis of cardiomyocytes exposed to OGD/R. Bioinformatical analysis revealed that naringin upregulated miR-126 expression considerably. Also, it was found that miR-126 can bind GSK-3β and downregulate its expression, suggesting that naringin could decrease GSK-3β activity. Next, we discovered that naringin increased β-catenin activity in cardiomyocytes treated with OGD/R by inhibiting GSK-3β expression. Our animal experiments showed that naringin pre-treatment or miR-126 agomir alleviated myocardial I/R.

Conclusions:

Naringin preconditioning can reduce myocardial I/R injury via regulating miR-126/GSK-3β/β-catenin signaling pathway, and this chemical can be used to treat acute myocardial infarction.