Sphingolipids and Cholesterol.

Sphingolipids and cholesterol are two lipid partners on cellular membranes where they form specific microdomains, named lipid rafts, which mediate specific cell functions. Sphingomyelin (SM) is one of the major sphingolipids. SM and free cholesterol are also two key lipids on the monolayer of plasma lipoproteins, including chylomicron, very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL), which participate in lipid transport in the circulation. Thus, sphingolipids and cholesterol play a fundamental role in cell membrane structure and blood lipid transport. In this chapter we will discuss the relationship between both lipids, on the cell membrane and in the circulation, as well as the impact of such relationship in the development of metabolic diseases.