WNT1 and Parkinson disease: Hence, in three PD cellular models (i.e., serum deprivation, SD, 6-OHDA, and MPP+) applied to enriched primary mesencephalic neurons expressing the dopamine transporter (DAT) at high levels, a dramatic caspase3-dependent DAergic neuronal death followed the toxic challenge, whereas the preventive application of Wnt1 fully prevented DAergic neuron death and efficiently reversed β-catenin downregulation, both at mRNA and protein levels [50].