Title:miR-199b-5p-AKAP1-DRP1 Pathway Plays a Key Role in ox-LDL-induced
Mitochondrial Fission and Endothelial Apoptosis
Volume: 23
Issue: 13
Author(s): Xiaolei Cui, Yingping Tian, Yapei Zhao, Hengbo Gao, Dongqi Yao, Liang Liu and Yongjun Li*
Affiliation:
- Department of Cardiology,
The Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
Keywords:
miR-199b-5p, AKAP1, mitochondrial fission, DRP1, apoptosis, endothelial cell.
Abstract:
Background: Atherosclerosis (AS) remains prevalent despite hyperlipidemia-lowering
therapies. Although multiple functions of miR-199b-5p have been implicated in cancers, its role in
endothelial apoptosis and AS remains unclear. This study aimed to examine the role of miR-199b-5p
in mitochondrial dynamics and endothelial apoptosis.
Methods: Human umbilical vein endothelial cells (HUVECs) treated with oxidized low-density lipoprotein
(ox-LDL) were subjected to other treatments, followed by a series analysis. We found that
ox-LDL-treated HUVECs were associated with miR-199b-5p downregulation, increased reactive
oxygen species level, reduced adenosine triphosphate (ATP) production, mitochondrial fission, and
apoptosis, whereas enhanced miR-199b-5p expression or applied mitochondrial division inhibitor 1
(Mdivi-1) markedly reversed these changes.
Results: Mechanistically, A-kinase anchoring protein 1 (AKAP1) was confirmed as a downstream
target of miR-199b-5p by dual-luciferase activity reporter assay. AKAP1 overexpression reversed
the anti-apoptotic effects of miR-199b-5p through the enhanced interaction of AKAP1 and dynamin
protein 1 (DRP1) in ox-LDL–treated HUVECs. Moreover, miR-199b-5p downregulation, AKAP1
upregulation, and excessive mitochondrial fission were verified in human coronary AS endothelial
tissues.
Conclusion: The miR-199b-5p-dependent regulation of AKAP1/DRP1 is required to inhibit hyperlipidemia-
induced mitochondrial fission and endothelial injury and may be a promising therapeutic
target for AS.