Inflammation induced Vascular Smooth Muscle Cell expressing Angiopoietin-like 2 to promote the development of abdominal aortic aneurysm

Abstract

Objective: The objective of this study is to investigate the expression of angiopoietin-like protein 2 (Angptl2) in abdominal aortic aneurysm (AAA) and the expression of Angptl2 in vascular smooth muscle cells (VSMC) under inflammation stimuli. Methods: The mouse AAA model was induced by applying calcium chloride method based the literature and the expression of Angptl2 in AAA was investigated by immunohistochemical staining. The primary VSMCs were cultured and identified following with inflammatory stimuli by Escherichia coli lipopolysaccharide (LPS) for 30 minutes and 24 hours. The expression of Angptl2 were assessed by RT-qPCR and ELISA. Results: The mouse AAA model was successfully established after being induced by calcium chloride. The inflammatory cell infiltration in the arterial tissue of the mice in the experimental group was obvious, and the elastic fiber layer was thinned and broken. Immunohistochemical staining showed that the expression of Angptl2 in AAA was up-regulated; After LPS treatment, both the mRNA and protein expressions of Angptl2 were significantly up-regulated in VSMCs in the experimental group compared with control group. Conclusion: Angptl2 expressed in VSMCs promotes the development of calcium chloride induced AAA.