The role of macrophages in aortic physiology and pathophysiology

The aorta is one of the major arterial vessels in the human body, serving as the principal conduit for the high-velocity blood ejected from the heart. For a long time, its function was largely understood in this limited hemodynamic context. However, with the advancement of research, its roles in metabolism, endocrine regulation, neurovascular modulation, and immune responses to stress have been increasingly recognized. Notably, the 2024 guidelines jointly issued by the European Association for Cardio-Thoracic Surgery (EACTS) and the Society of Thoracic Surgeons (STS) have, for the first time, formally proposed that the aorta should be regarded as an "independent organ." This conceptual paradigm shift marks a new stage in the understanding of aortic biology and function. Macrophages are key components of the innate immune system and have attracted extensive attention due to their remarkable heterogeneity across diverse physiological and pathological conditions. In recent years, multiple macrophage subsets have been identified within the Aortic Physiology where they have been shown to play essential roles not only in vascular homeostasis but also in a wide spectrum of disease-related processes. This review systematically summarizes the roles of macrophages in both the physiological and pathophysiological contexts of the aorta, with the aim of providing new insights and potential directions for future research, as well as novel perspectives for the diagnosis and treatment of aortic diseases.