Monocarboxylate Transport Matters

The liver makes ketone bodies (3-hydroxybutyrate, acetoacetate, and acetone, the breakdown product of acetoacetate) from fat when intracellular glucose is in short supply — for example, in starvation or unregulated diabetes. The generated 3-hydroxybutyrate and acetoacetate serve as alternative energy sources for the cells. However, when the production of ketone bodies greatly exceeds cellular consumption, the potentially lethal condition of ketoacidosis can occur. How do ketone bodies get out of hepatocytes and into cells in other parts of the body to be metabolized? Ketone bodies and other monocarboxylates, such as lactate and pyruvate, are transported out of and into cells . . .