Endothelial Hypoxia-Inducible Factor-1α Promotes Atherosclerosis and Monocyte Recruitment by Upregulating MicroRNA-19a. Issue 6 (December 2015)

• Record Type: Journal Article
• Authors: Akhtar, Shamima; Hartmann, Petra; Karshovska, Ela; Rinderknecht, Fatuma-Ayaan; Subramanian, Pallavi; Gremse, Felix; Grommes, Jochen; Jacobs, Michael; Kiessling, Fabian; Weber, Christian; Steffens, Sabine; Schober, Andreas
• Is Part Of: Hypertension. Volume 66:Issue 6(2015:Dec.)
• Publication Date: 2015-12
• Subjects: atherosclerosis -- chemokines -- endothelial cells -- microRNAs; Hypertension -- Periodicals; Hypertension -- Treatment -- Periodicals; 616.132005
• DOI: 10.1161/HYPERTENSIONAHA.115.05886
• Languages: English
• ISSNs: 0194-911X

Abstract

Abstract : Chemokines mediate monocyte adhesion to dysfunctional endothelial cells (ECs) and promote arterial inflammation during atherosclerosis. Hypoxia-inducible factor (HIF)-1α is expressed in various cell types of atherosclerotic lesions and is associated with lesional inflammation. However, the impact of endothelial HIF-1α in atherosclerosis is unclear. HIF-1α was detectable in the nucleus of ECs covering murine and human atherosclerotic lesions. To study the role of endothelial HIF-1α in atherosclerosis, deletion of the Hif1 a gene was induced in ECs from apolipoprotein E knockout mice (EC- Hif1a −/− ) by Tamoxifen injection. The formation of atherosclerotic lesions, the lesional macrophage accumulation, and the expression of CXCL1 in ECs were reduced after partial carotid ligation in EC- Hif1a −/− compared with control mice. Moreover, the lesion area and the lesional macrophage accumulation were decreased in the aortas of EC- Hif1a −/− mice compared with control mice during diet-induced atherosclerosis. In vitro, mildly oxidized low-density lipoprotein or lysophosphatidic acid 20:4 increased endothelial CXCL1 expression and monocyte adhesion by inducing HIF-1α expression. Moreover, endothelial Hif1a deficiency resulted in downregulation of miR-19a in atherosclerotic arteries determined by microRNA profiling. In vitro, HIF-1α–induced miR-19a expression mediated the upregulation of CXCL1 in mildly oxidized low-density lipoprotein–stimulated ECs. These results indicate that hyperlipidemia upregulates HIF-1α expression in ECs by mildly oxidized low-density lipoprotein–derived unsaturated lysophosphatidic acid. Endothelial HIF-1α promoted atherosclerosis by triggering miR-19a–mediated CXCL1 expression and monocyte adhesion, indicating that inhibition of the endothelial HIF-1α/miR-19a pathway may be a therapeutic option against atherosclerosis. Abstract : Supplemental Digital Content is available in the text.