title: Sustained high levels of neuroprotective, high molecular weight, phosphorylated tau in the longest-lived rodent.
abstract: Tau protein is primarily expressed in neuronal axons and modulates microtubule stability. Tau phosphorylation, aggregation, and subcellular mislocalization coincide with neurodegeneration in numerous diseases, including Alzheimer's disease (AD). During AD pathogenesis, tau misprocessing accompanies Aß accumulation; however, AD animal models, despite elevated Aß, fail to develop tauopathy. To assess whether lack of tau pathology is linked to short life span common to most AD models, we examined tau processing in extraordinarily long-lived, mouse-sized naked mole-rats (NMRs; approximately 32 years), which express appreciable levels of Aß throughout life. We found that NMRs, like other mammals, display highest tau phosphorylation during brain development. Although tau phosphorylation decreases with aging, unexpectedly adult NMRs have higher levels than transgenic mice overexpressing mutant human tau. However, in sharp contrast with the somatodendritic accumulation of misprocessed tau in the transgenic mice, NMRs maintain axonal tau localization. Intriguingly, the adult NMR tau protein is 88 kDa, much larger than 45-68 kDa tau expressed in other mammals. We propose that this 88 kDa tau protein may offer exceptional microtubule stability and neuroprotection against lifelong, elevated Aß.
authors.affiliation: Department of Physiology and The Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
authors.forename: Miranda E
authors.initials: ME
authors.lastname: Orr
authors.affiliation: Department of Physiology and The Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
authors.forename: Valentina R
authors.initials: VR
authors.lastname: Garbarino
authors.affiliation: Department of Physiology and The Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
authors.forename: Angelica
authors.initials: A
authors.lastname: Salinas
authors.affiliation: Department of Physiology and The Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA. Electronic address: buffenstein@uthscsa.edu.
authors.forename: Rochelle
authors.initials: R
authors.lastname: Buffenstein
mesh_terms: D000375:Aging / Q000235:genetics* / Q000378:metabolism*; D000544:Alzheimer Disease / Q000378:metabolism / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000378:metabolism; D000818:Animals; D001369:Axons / Q000378:metabolism; D001921:Brain / Q000378:metabolism* / Q000473:pathology*; D004195:Disease Models, Animal; D008136:Longevity / Q000235:genetics*; D008822:Mice, Transgenic; D019577:Mole Rats; D008970:Molecular Weight; D010766:Phosphorylation; D024801:Tauopathies; D016875:tau Proteins / Q000032:analysis* / Q000378:metabolism*
chemical_list: D016229:Amyloid beta-Peptides; D016875:tau Proteins
keywords: Aging; Alzheimer's disease; Animal model; Naked mole-rat; Phosphorylation; Tau