The role of cholesterol in cardiovascular remodeling during weightlessness or simulated weightlessness

Cholesterol (CHO) is a crucial component of lipids that maintains the fluidity of cell membranes. Meanwhile, CHO regulates various signaling pathways underpinning generation of bile acids, steroid hormones and vitamin D. The strict control over cholesterol’s uptake, synthesis, esterification, movement, transport, and transformation plays a significant role in the development of cardiovascular diseases (CVDs) through mechanisms such as promoting arterial plaque formation, disrupting lipid raft structure, and inducing inflammatory responses. Exposure to weightlessness or simulated weightlessness can elevate CHO levels in serum and tissues, primarily due to changes in hemodynamics, energy metabolism, and the neuroendocrine system. This shift triggers cardiovascular remodeling, prompting medical recommendations for a relatively low dietary CHO intake for astronauts both at home and abroad. This review provides a comprehensive overview of CHO metabolism and its regulation. Furthermore, it delves into the role of CHO in CVDs and the cardiovascular adaptations observed during weightlessness or simulated weightlessness.