Sodium selenate mitigates tau pathology, neurodegeneration, and functional deficits in Alzheimer's disease models.
Alzheimer's disease (AD) brains are characterized by amyloid-beta-containing plaques and hyperphosphorylated tau-containing neurofibrillary tangles (NFTs); however, in frontotemporal dementia, the tau pathology manifests in the absence of overt amyloid-beta plaques. Therapeutic strategies so far have primarily been targeting amyloid-beta, although those targeting tau are only slowly beginning to emerge. Here, we identify sodium selenate as a compound that reduces tau phosphorylation both in vitro and in vivo. Importantly, chronic oral treatment of two independent tau transgenic mouse strains with NFT pathology, P301L mutant pR5 and K369I mutant K3 mice, reduces tau hyperphosphorylation and completely abrogates NFT formation. Furthermore, treatment improves contextual memory and motor performance, and prevents neurodegeneration. As hyperphosphorylation of tau precedes NFT formation, the effect of selenate on tau phosphorylation was assessed in more detail, a process regulated by both kinases and phosphatases. A major phosphatase implicated in tau dephosphorylation is the serine/threonine-specific protein phosphatase 2A (PP2A) that is reduced in both levels and activity in the AD brain. We found that selenate stabilizes PP2A-tau complexes. Moreover, there was an absence of therapeutic effects in sodium selenate-treated tau transgenic mice that coexpress a dominant-negative mutant form of PP2A, suggesting a mediating role for PP2A. Taken together, sodium selenate mitigates tau pathology in several AD models, making it a promising lead compound for tau-targeted treatments of AD and related dementias.
van Eersel
Janet
J
Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, Department of Pathology, University of Sydney, Camperdown, New South Wales 2050, Australia.
Ke
Yazi D
YD
Liu
Xin
X
Delerue
Fabien
F
Kril
Jillian J
JJ
Götz
Jürgen
J
Ittner
Lars M
LM
D000544:Alzheimer Disease / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D000818:Animals; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D008568:Memory / Q000187:drug effects; D051379:Mice; D008822:Mice, Transgenic; D009154:Mutation; D009410:Nerve Degeneration / Q000188:drug therapy* / Q000378:metabolism* / Q000503:physiopathology; D010766:Phosphorylation / Q000187:drug effects; D010805:Physical Conditioning, Animal; D054648:Protein Phosphatase 2 / Q000378:metabolism; D064586:Selenic Acid; D018036:Selenium Compounds / Q000627:therapeutic use*; D016875:tau Proteins / Q000235:genetics / Q000378:metabolism*
D018036:Selenium Compounds; D016875:tau Proteins; D054648:Protein Phosphatase 2; D064586:Selenic Acid