# Paeonol attenuated high glucose-induced apoptosis via up-regulating miR-223-3p in mouse cardiac microvascular endothelial cells

## TL;DR

Paeonol reduces high glucose-induced cell death in mouse heart cells by boosting miR-223-3p, which in turn lowers harmful NLRP3 levels and apoptosis proteins.

## Contribution

This study reveals a novel mechanism by which paeonol protects endothelial cells via miR-223-3p upregulation and NLRP3 inhibition.

## Key findings

- Paeonol significantly reduced high glucose-induced apoptosis in mouse cardiac microvascular endothelial cells.
- Paeonol reversed high glucose-induced downregulation of miR-223-3p and upregulation of NLRP3.
- Exogenous miR-223-3p mimics suppressed apoptosis and pro-apoptotic proteins in high glucose conditions.

## Abstract

To investigate the role of miR-223-3p in the modulatory effect of paeonol (Pae) on high glucose (HG)-induced endothelial cell apoptosis. HG (25 mmol/L) was used to induce cellular damage and apoptosis in the mouse cardiac microvascular endothelial cells (MCMECs). Various concentration of Pae was tested and 60 μmol/L Pae was selected for the subsequent studies. MCMECs were transfected with exogenous miR-223-3p mimics or anti-miR-223-3p inhibitors. Cell viability was assessed by MTT assay and apoptosis was quantified by flow cytometry. The expression of miR-223-3p and NLRP3 mRNA was measured using real-time quantitative RT-PCR, and protein level of NLRP3 and apoptosis-related proteins was detected by immunoblotting. Pae significantly attenuated HG-induced apoptosis of MCMECs in a concentration-dependent manner. In addition, Pae (60 µmol/L) significantly reversed HG-induced down-regulation of miR-223-3p and up-regulation of NLRP3. Pae (60 µmol/L) also significantly blocked HG-induced up-regulation of Bax and Caspase-3 as well as down-regulation of Bcl-2. Moreover, exogenous miR-223-3p mimics not only significantly attenuated HG-induced apoptosis, but also significantly suppressed NRLP-3 and pro-apoptotic proteins in the MCMECs. In contrast, transfection of exogenous miR-223-3p inhibitors into the MCMECs resulted in not only significantly increased apoptosis of the cells, but also significant suppression of NLRP3 and pro-apoptotic proteins in the cells. Pae attenuated HG-induced apoptosis of MCMECs in a concentration-dependent manner. MiR-223-3p may mediate the modulatory effects of Pae on MCMEC survival or apoptosis through targeting NLRP3 and regulating apoptosis-associated proteins.