The year of 2007 was a turning point of the treatment of Parkinson's disease (PD) in Japan. Severe adverse effects of dopamine agonists including valvular heart disease induced by ergots and sudden onset of sleep attacks induced by non-ergots, were disclosed, and treatments with agonists were reassessed. Good news were marketing of ropinirole, a new non-ergot agonist, in December 2006 and entacapone, the first catechol-O-methyl transferase (COMT) inhibitor in Japan in April 2007. Having faced these new situations, Japanese Neurological Association has started revising "the Guideline 2002 for the treatment of Parkinson's disease".
Clinical trials of translational gene therapy for Parkinson's disease with adeno-associated virus (AAV) vector are now going on in four approaches; restoring dopamine synthetic capacity, protecting against cell death with trophic factors, interfering with the aberrant protein aggregation, and converting the subthalamic nucleus into an inhibitory, rather than an excitatory, structure. In Japan, gene delivery of the dopamine synthesizing enzyme aromatic amino acid decarboxylase (AADC) to the striatum of PD patients is going on in Jichi Medical University. New findings of the causative genes, environmental factors and molecular mechanism of PD have provided with new tools for developing new treatments. The big success of induction of induced pluripotent stem (iPS) cells from fibroblast has given an impact on cell therapy research of PD.
