Vitamin K and Brain Function

One of the fat-soluble vitamins, vitamin K was initially discovered for its role in blood coagulation. Although several vitamin K–dependent hemostatic proteins are particularly important for the brain, other vitamin K–dependent proteins (VKDPs), not associated with blood coagulation, also contribute to the brain function. In addition to the VKDPs, vitamin K participates in the nervous system through its involvement in sphingolipid metabolism, a class of lipids widely present in brain cell membranes. Classically known for their structural role, sphingolipids are biologically potent molecules involved in a wide range of cellular actions. Also, there is growing evidence that the K vitamer, menaquinone-4, has anti-inflammatory activity and offers protection against oxidative stress. Finally, although limited in numbers, reports point to a modulatory role of vitamin K in cognition. This short review presents an overview of the known role of vitamin K in brain function to date.