Neopterin and Cytokines in Hereditary Dystonia and Parkinson's Disease

β Both neopterin and biopterin concentrations in cerebrospinal fluid from patients with Parkinson's disease, in which the nigrostriatal dopamine neurons degenerate, were lower than those from age-matched older control subjects. However, the decrease in biopterin was more marked than that in neopterin, resulting in the increase in the neopterin/ biopterin ratio in Parkinson's disease. These results suggests that neopterin in cerebrospinal fluid in Parkinson's disease may partly be derived from immunoactivated glial cells, besides catecholamine or serotonin n eurons including nigrostriatal dopamine neurons. In accordance to this hypothesis, cytokines (TNF-α, IL-1, IL-2 , IL-6, EGF, TGF-α, TGF-β1) were found to be increased in the striatum and/or in cerebrospinal fluid. The increment of cytokines in the brain in Parkinson's disease may be related to the mechanism of neurodegeneration of dopaminergic neurons in Parkinson's disease . In contrast to Parkinson's disease, in hereditary progressive dystonia/ dopa-responsive dystonia, which is a dopamine deficiency caused by mutations in GTP cyclohydrolase I without neuronal cell death (Segawa's disease), neopterin and biopterin in cerebrospinal fluid decreases in parallel owing to the decreased activity in GTP cyclohydrolase I .