NMNAT1 and semantic dementia: Over-expression of different isoforms of NMNAT can significantly reduce the abnormal aggregation (Zhai et al., 2008) and cytotoxicity of pTau and relieve pTau burden in different models of AD (Rossi et al., 2018) and frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17) (Ali et al., 2012; Ljungberg et al., 2012).