Since NM is produced from oxyradical metabolites of monoamine neuroamine neurotransmitters including DA [60], the observed increase of melanin content in α-Syn over-expressed dopaminergic neuronal SH-SY5Y and PC12 cells, cellular models relevant to PD, could be mainly explained by the increased cytosolic DA due to the loss of α-Syn function on the inhibition of TH. The gene discussed is TH; the disease is Parkinson disease.