Caveolae and Lipid Rafts in Endothelium: Valuable Organelles for Multiple Functions

Abstract

Caveolae are flask-shaped invaginations of the plasma membrane found in numerous cell types and are particularly abundant in endothelial cells and adipocytes. The lipid composition of caveolae largely matches that of lipid rafts microdomains that are particularly enriched in cholesterol, sphingomyelin, glycosphingolipids, and saturated fatty acids. Unlike lipid rafts, whose existence remains quite elusive in living cells, caveolae can be clearly distinguished by electron microscope. Despite their similar composition and the sharing of some functions, lipid rafts appear more heterogeneous in terms of size and are more dynamic than caveolae. Following the discovery of caveolin-1, the first molecular marker as well as the unique scaffolding protein of caveolae, we have witnessed a remarkable increase in studies aimed at investigating the role of these organelles in cell functions and human disease. The goal of this review is to discuss the most recent studies related to the role of caveolae and caveolins in endothelial cells. We first recapitulate the major embryological processes leading to the formation of the vascular tree. We next discuss the contribution of caveolins and cavins to membrane biogenesis and cell response to extracellular stimuli. We also address how caveolae and caveolins control endothelial cell metabolism, a central mechanism involved in migration proliferation and angiogenesis. Finally, as regards the emergency caused by COVID-19, we propose to study the caveolar platform as a potential target to block virus entry into endothelial cells.

Targeting Lipid Rafts as a Strategy Against Coronavirus

“…Furthermore, at the cellular level, rafts and related membrane microdomains, such as caveolae, characterized by a high expression of caveolin-1, have been proposed to play important roles in the sorting of membrane and non-membrane molecules (Browne and London, 2000 ; Parton and Richards, 2003 ). In fact, the study of caveolar platform has been proposed as a potential target to inhibit the entry of SARS-CoV-2 (Filippini and D'Alessio, 2020 ).…”

“…Alternatively, a caveolae-dependent pathway may be used. Caveolae are small invaginations of the plasma membrane that are composed of cholesterol, glycosphingolipids, and caveolin (Filippini and D'Alessio, 2020 ). Caveolin is able to oligomerize, leading to the formation of caveolin-rich microdomains in the plasma membrane, and subsequently, the caveolar vesicles may fuse with the early endosomal compartment.…”

Role of caveolin‑1 in chronic postsurgical pain in rats

“…The purpose of the present study was to explore the role of Cav-1 in peripheral sensitization, starting with the alterations of the peripheral incision tissue. The caveolae are a special form of lipid raft, which is a small invagination of the plasma membrane that is present in a number of mammalian cells, such as endothelial cells, adipocytes and skeletal muscle ( 27 , 28 ). Previous studies have reported that caveolae are the cellular center of signaling molecules ( 9 , 10 , 29 ).…”

Cholesterol and Sphingolipid Enriched Lipid Rafts as Therapeutic Targets in Cancer

“…Moreover, some recognition receptors for viruses, including coronavirus, cluster into lipid rafts [ 7 ]. Thus, lipid platforms are considered as potential targets to block virus entry into endothelial cells [ 8 ].…”