Does Endothelium Buffer Fat?

Endothelial cells (ECs) are the metabolic gatekeepers of the body. All tissues require nutrients for growth and function, and those nutrients must pass the endothelial layer. In some tissues like the liver, the endothelium is discontinuous and marked by “fenestrae” (from the Latin for “window”), dedicated transcellular openings that allow free movement of nutrients. But in most tissues such as the heart, muscle, and brain, endothelia lack fenestrae, and nutrients must traverse the endothelial wall directly. The list of nutrients that must do so is long and includes sugars, amino acids, and fats. Of those, the latter have received the least attention, although organs like the heart consume copious fatty acids for the generation of ATP.