[Elucidation of Physiological Functions of Vitamin K in the Brain and Development of New Derivatives for Neuroregeneration].

Vitamin K plays an important role in blood coagulation and bone formation. However, apart from the liver and bone, the role of vitamin K in other tissues remains unknown. Previously, we have reported on high concentrations of vitamin K in the mouse brain and investigated vitamin K conversion in brain tissue. This led us to hypothesised the possibility of vitamin K contributing significantly towards maintenance and function of the cranial nervous system. In this review, we summarise the synthesis of novel vitamin K derivatives, their neuronal differentiation inducing activities and the induction mechanism. The findings from this study will provide insights into the physiological roles of vitamin K in the brain.