Vitamin K and sphingolipid metabolism: evidence to date.

The brain is enriched with sphingolipids, which are important membrane constituents and major lipid signaling molecules that have a role in motor and cognitive behavior. Vitamin K has been implicated in brain sphingolipid metabolism for more than 30 years. The in vitro and in vivo studies to date suggest a role of vitamin K in the regulation of multiple enzymes involved in sphingolipid metabolism within the myelin-rich regions in the brain. However, the precise mechanisms of action are not well understood. Further, the physiological consequences of the observed effects of vitamin K on sphingolipid metabolism have not been systematically studied.