The blood-brain barrier-a metabolic ecosystem.

A functional blood-brain barrier relies on a tightly controlled interplay between endothelial cells, pericytes, and astrocytes, which together form the neurovascular unit. Recent work by Lee et al (2022) discovers endothelial cell-derived lactate as a crucial metabolic fuel for brain pericytes, revealing a new way of CNS vascular communication that links nutrient metabolism to blood-brain barrier function.