51. Pravastatin activates activator protein 2 alpha to augment the angiotensin II-induced abdominal aortic aneurysms.
- Author
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Ma H, Liang WJ, Shan MR, Wang XQ, Zhou SN, Chen Y, Guo T, Li P, Yu HY, Liu C, Yin YL, Wang YL, Dong B, Pang XY, and Wang SX
- Subjects
- Animals, Anticholesteremic Agents pharmacology, Aortic Aneurysm, Abdominal metabolism, Aortic Aneurysm, Abdominal pathology, Blotting, Western, Cells, Cultured, Disease Models, Animal, Humans, Male, Mice, Mice, Knockout, Myocytes, Smooth Muscle drug effects, Myocytes, Smooth Muscle metabolism, Myocytes, Smooth Muscle pathology, Phosphorylation, Signal Transduction, AMP-Activated Protein Kinases metabolism, Angiotensin II adverse effects, Aortic Aneurysm, Abdominal etiology, Apolipoproteins E physiology, Gene Expression Regulation drug effects, Pravastatin adverse effects, Transcription Factor AP-2 metabolism
- Abstract
We have previously reported that activation of AMP-activated kinase alpha 2 (AMPKα2) by nicotine or angiotensin II (AngII) instigates formation of abdominal aortic aneurysms (AAA) in Apoe-/- mice. Statins, used to treat hyperlipidemia widely, activate AMPK in vascular cells. We sought to examine the effects of pravastatin on AAA formation and uncover the molecular mechanism. The AAA model was induced by AngII and evaluated by incidence, elastin degradation, and maximal abdominal aortic diameter in Apoe-/- mice. The phosphorylated levels of AMPKα2 and activator protein 2 alpha (AP-2α) were examined in cultured vascular smooth muscle cells (VSMCs) or in mice. We observed that pravastatin (50 mg/kg/day, 8 weeks) remarkably increased the AngII-induced AAA incidence in mice. In VSMCs, pravastatin increased the levels of pAMPK, pAP-2α, and MMP2 in both basal and AngII-stressed conditions, which were abolished by tempol and compound C. Pravastatin-upregulated MMP2 was abrogated by AMPKα2 or AP-2α siRNA. Lentivirus-mediated gene silence of AMPKα2 or AP-2α abolished pravastatin-worsened AAA formations in AngII-infused Apoe-/- mice. Clinical investigations demonstrated that both AMPKα2 and AP-2α phosphorylations were increased in AAA patients or human subjects taking pravastatin. In conclusion, pravastatin promotes AAA formation through AMPKα2-dependent AP-2α activations.
- Published
- 2017
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