MAPT and Parkinsonism: Consistent with this, GSK3β transgenic mice display tau hyper-phosphorylation and neurodegeneration (Lucas et al. 2001) and chronic lithium (GSK3 inhibitor) treatment prevents tau hyper-phosphorylation and NFT formation in double transgenic mice over-expressing GSK3β and tau (harboring a triple mutation associated with frontotemporal dementia and parkinsonism linked to chromosome 17), although reversal of pre-formed tangles was not observed (Engel et al. 2006).