Recent Highlights of ATVB

Abstract

Aortic diseases are common in many populations and are receiving increasing research focus. There are a broad spectrum of aortic diseases that occur in specific regions and appear to have different causes. For example, abdominal aortic aneurysms (AAAs) are most common in aged men.1 In contrast, many forms of thoracic aortic aneurysms (TAAs) occur early in life with a strong genetic basis and no sex discrimination.2 Both aortic aneurysms are amenable to surgical repair. Although surgical approaches have become increasingly sophisticated and less invasive,3 there remains an urgent need to determine factors that predispose to susceptibility and to divert treatment from surgical to medical approaches.4,5 This switch to medical treatment will require an increased knowledge of the mechanisms for several facets of aneurysms that cover the span of initiation, progression, and rupture. In this regard, many recent publications in ATVB have provided further insight into established pathways contributing to aneurysm development such as proteolysis, inflammation, and attenuation of the medial smooth muscle cell population, and a few publications have raised the possibility of new pathways such as adipokines and mineralocorticoid signaling. This article highlights these recent publications within a brief context of the literature. Cigarette smoking remains the major risk factor for development and progression of AAAs.6,7 Several experimental studies have demonstrated that smoke exposure augments AAA induced in mice by either subcutaneous angiotensin II (AngII) infusion or intra-aortic elastase perfusion.8,9 However, it is unclear whether cessation of smoking impacts the development of AAAs. The study of Jin et al10 demonstrated that cessation of cigarette smoking exposure did not immediately decrease the augmentation of AAAs. This sustained effect was attributable to regulation of leukocytic metabolism. Also of note is that cigarette smoking–induced augmentation of AAAs was unaffected …