Abstract

Background: Recent studies have provided evidence that microRNAs (miRNAs), as a potential biomarker, were involved in the regulation of gene expression in Myocardial Infarction (MI). This study aimed to highlight the role of salvianolate on cardiomyocyte apoptosis in MI.

Methods: Anterior descending branch of left coronary artery was ligated to set up MI model. MiR- 122-5p mimic was transfected into cardiomyocytes and verified by quantitative real-time PCR (qRT-PCR). Cell viability and apoptotic rate were measured by MTT assay and flow cytometry together with TUNEL method, respectively. Changes in the expression of caspase-3, Bax and Bcl-2 were quantified by qRT-PCR and western blot.

Results: After treatment with salvianolate, miR-122-5p expression and caspases-3 activity significantly decreased in rat myocardial tissues. Furthermore, cardiomyocytes apoptosis rate was obviously suppressed while cell viability dramatically increased in H9C2 cardiomyocytes. However, overexpression of miR-122-5p reversed the aforementioned trends. Simultaneously, it could also mitigate the anti-apoptosis effect of salvianolate on the upregulation of caspases-3 viability and Bax expression and downregulation of Bcl-2 expression.

Conclusion: Salvianolate induces the anti-apoptosis mechanism of cardiomyocytes via downregulation of miR-122-5p, Bax expression and caspases-3 as well as upregulation of Bcl-2 expression. In contrast, overexpression of miR-122-5p inhibits the effect of salvianolate.

Keywords: miR-122-5p, apoptosis, salvianolate, Bcl-2, caspases-3, Bax.