Abstract
We examined and reviewed the association between Parkinson's disease and vitamin B status. Thiamin triphosphate (TIP), but not thiamin, increased dopamine (DA) release from the rat striatum. We concluded that TTP could enhance the Na^+ permeability of the membrane, depolarize nerve cells, and sequentially cause a Ca^<2+> influx, inducing DA release. DOPA administration enhanced the elevation of serum homocysteine level. Hyperhomocysteinemia is considered to be a risk factor of Parkinson's disease as well as vascular diseases and Alzheimer's disease. Folate, vitamin B_<12>, or vitamin B_6 could potentially reduce the level of serum homocysteine. We reported that folate deficiency was not a rare condition in elderly neurological patients in Japan. They showed both peripheral and central nervous system disorders, including dementia. Folate supplementation had beneficial effects for two-thirds of the patients. Although further studies are needed, folate and other vitamins might have an inhibitory effect on the progression of Parkinson's disease.
