Mechanistic Insight into PVAT Browning as a Protective Factor in Thoracic Aortic Aneurysm

This review aims to provide a comprehensive overview of emerging evidence supporting the protective effects of perivascular adipose tissue (PVAT) browning in the pathophysiology of thoracic aortic aneurysm (TAA).

PVAT is increasingly recognized as an active regulator of vascular homeostasis. During cardiovascular disease (CVD), PVAT undergoes a phenotypic shift from a protective brown/beige state to a dysfunctional white phenotype, contributing to vascular remodeling. Accumulating data supports beneficial effects of PVAT browning on key mechanisms involved in TAA development, including endothelial dysfunction, vascular smooth muscle cell phenotypic switching, adventitial remodeling and PVAT phenotypic shift. Studies highlight PRDM16 as a central regulator of PVAT browning, with its deficiency promoting PVAT dysfunction, adventitial fibrosis, and TAA formation. Strategies aimed at enhancing PVAT browning represent a promising therapeutic direction. However, significant gaps remain in our understanding of human PVAT biology, its interaction with the aortic wall, and the development of specific imaging tools or biomarkers. Further research is needed to clarify PVAT's role in TAA pathophysiology and to advance browning-based interventions.