Vitamin K: a Potential Neuroprotective Agent

Neurodegeneration, a progressive disease due to the arrested development of atrophy and regression of neuron function, is the most common disorder people go through. The treatment of the disease is generally symptomatic, and after a certain time, the effectivity of the drug decreases. A less toxic compound, vitamin K, a lipophilic (fat-soluble) vitamin, shows some promising results. Generally, vitamin K is found in three different forms: phylloquinone (vitamin K1) from green vegetables, menaquinone (vitamin K2) from anaerobic bacteria, and synthetic analog menadione (vitamin K3). The biological activities of each form of vitamin K differ from each other. Vitamin K1 is mainly stored in the liver and has a more prominent role in forming coagulation proteins. On the other hand, vitamin K2 is widely dispersed throughout the human body. Here in this review, the therapeutic role of vitamin K in different disorders, mainly focusing the neurological disorders, including neuroinflammation, Parkinson’s disease, Alzheimer’s disease, and multiple sclerosis, is discussed. As a limited number of laboratories are involved in understanding vitamin K as a neuroprotective agent, the review will encourage further exploration in validating the neuroprotective effects of vitamin K among the pharmacognostic community. Graphical abstract