Review article: Biomedical intelligence
Vol. 144 No. 4546 (2014)
Toxic oligomer species of amyloid-β in Alzheimer's disease, a timing issue
Summary
A decade following the paradigm-shifting concept that endogenous forms of soluble, non-fibrillar amyloid-β (Aβ) might constitute the major bioactive entity causing synaptic loss and cognitive decline in Alzheimer’s disease (AD), our understanding of these oligomeric species still remains conspicuously superficial. The current lack of direct evaluation tools for each endogenous Aβ oligomer hampers our ability to readily address crucial question such as: (i) where they form and accumulate?; (ii) when they first appear in human brains and body fluids?; (iii) what is the longitudinal expression of these putative toxins during the course of the disease?; (iv) and how do these soluble Aβ assemblies alter synaptic and neuronal function in the brain? Despite these limitations, indirect ex vivo measurement and isolation from biological specimens has been possible and have allowed parsing out intrinsic differences between putative endogenous Aβ oligomers. In this review, I integrated recent findings and extrapolated emerging hypotheses derived from these studies with the hope to provide a clarified view on the putative role of endogenous Aβ oligomers in AD, with a particular emphasis on the timing at which these soluble species might act in the aging and diseased brain.
References
- Serrano-Pozo A, Frosch MP, Masliah E & Hyman BT. Neuropathological alterations in Alzheimer disease. Cold Spring Harbor perspectives in medicine. 2011;1:a006189, doi:10.1101/cshperspect.a006189.
- Reed MN, et al. Cognitive effects of cell-derived and synthetically derived Abeta oligomers. Neurobiol Aging. 2011;32:1784–94, doi:10.1016/j.neurobiolaging.2009.11.007.
- Jin M, et al. Soluble amyloid beta-protein dimers isolated from Alzheimer cortex directly induce Tau hyperphosphorylation and neuritic degeneration. Proc Natl Acad Sci U S A. 2011;108:5819–24, doi:10.1073/pnas.1017033108.
- Li S, et al. Soluble oligomers of amyloid Beta protein facilitate hippocampal long-term depression by disrupting neuronal glutamate uptake. Neuron. 2009;62:788–801, doi:10.1016/j.neuron.2009.05.012.
- Shankar GM, et al. Amyloid-beta protein dimers isolated directly from Alzheimer's brains impair synaptic plasticity and memory. Nat Med 2008;14:837–42, doi:10.1038/nm1782.
- Shankar GM, et al. Natural oligomers of the Alzheimer amyloid-beta protein induce reversible synapse loss by modulating an NMDA-type glutamate receptor-dependent signaling pathway. J Neurosci. 2007;27:2866–75, doi:10.1523/JNEUROSCI.4970–06.2007.
- Townsend M, Shankar GM, Mehta T, Walsh DM & Selkoe DJ. Effects of secreted oligomers of amyloid beta-protein on hippocampal synaptic plasticity: a potent role for trimers. J Physiol. 2006;572:477–92, doi:10.1113/jphysiol.2005.103754.
- Cleary JP, et al. Natural oligomers of the amyloid-beta protein specifically disrupt cognitive function. Nat Neurosci. 2005;8:79–84, doi:10.1038/nn1372.
- Walsh DM, et al. Naturally secreted oligomers of amyloid beta protein potently inhibit hippocampal long-term potentiation in vivo. Nature. 2002;416:535–39, doi:10.1038/416535a.
- Walsh DM, Tseng BP, Rydel RE, Podlisny MB & Selkoe DJ. The oligomerization of amyloid beta-protein begins intracellularly in cells derived from human brain. Biochemistry. 2000;39:10831–9.
- Lesne S, et al. A specific amyloid-beta protein assembly in the brain impairs memory. Nature. 2006;440:352–7, doi:10.1038/nature04533.
- Larson ME & Lesne SE. Soluble Abeta oligomer production and toxicity. J Neurochem. 2012;120:Suppl 1, 125–39, doi:10.1111/j.1471–4159.2011.07478.x.
- Walsh DM & Selkoe DJ. A beta oligomers – a decade of discovery. J Neurochem. 2007 ;101:1172–84, doi:10.1111/j.1471–4159.2006.04426.x.
- Lesne SE, et al. Brain amyloid-beta oligomers in ageing and Alzheimer's disease. Brain. 2013;136:1383–98, doi:10.1093/brain/awt062.
- Lasagna-Reeves CA, Glabe CG & Kayed R. Amyloid-{beta} Annular Protofibrils Evade Fibrillar Fate in Alzheimer Disease Brain. J Biol Chem. 2011;286:22122–30, doi:10.1074/jbc.M111.236257.
- Kayed R, et al. Annular protofibrils are a structurally and functionally distinct type of amyloid oligomer. J Biol Chem. 2009;284:4230–7, doi:10.1074/jbc.M808591200.
- Benilova I, Karran E & De Strooper B. The toxic Abeta oligomer and Alzheimer's disease: an emperor in need of clothes. Nat Neurosci. 2012;15:349–57, doi:10.1038/nn.3028.
- Ittner LM & Gotz. J. Amyloid-beta and tau--a toxic pas de deux in Alzheimer's disease. Nat Rev Neurosci. 2011;12:65–72, doi:10.1038/nrn2967.
- Huang Y & Mucke, L. Alzheimer mechanisms and therapeutic strategies. Cell. 2012;148:1204–22, doi:10.1016/j.cell.2012.02.040.
- Morris M, Maeda S, Vossel K & Mucke L. The many faces of tau. Neuron. 2011;70:410–26, doi:10.1016/j.neuron.2011.04.009.
- Ittner LM, et al. Dendritic function of tau mediates amyloid-beta toxicity in Alzheimer's disease mouse models. Cell. 2010;142:387–97, doi:10.1016/j.cell.2010.06.036.
- Roberson ED, et al. Reducing endogenous tau ameliorates amyloid beta-induced deficits in an Alzheimer's disease mouse model. Science. 2007;316:750–4, doi:10.1126/science.1141736.
- Hoover BR, et al. Tau mislocalization to dendritic spines mediates synaptic dysfunction independently of neurodegeneration. Neuron. 2010;68:1067–81, doi:10.1016/j.neuron.2010.11.030.
- Glabe CG & Kayed R. Common structure and toxic function of amyloid oligomers implies a common mechanism of pathogenesis. Neurology. 2006;66:S74–8, doi:10.1212/01.wnl.0000192103.24796.42.
- Kayed R, et al. Common structure of soluble amyloid oligomers implies common mechanism of pathogenesis. Science. 2003;300:486–9, doi:10.1126/science.1079469.
- McDonald JM, Cairns NJ, Taylor-Reinwald L, Holtzman D & Walsh DM. The levels of water-soluble and triton-soluble Abeta are increased in Alzheimer's disease brain. Brain research. 2012;1450:138–47, doi:10.1016/j.brainres.2012.02.041.
- Shankar GM, Welzel AT, McDonald JM, Selkoe DJ & Walsh DM. Isolation of low-n amyloid beta-protein oligomers from cultured cells, CSF, and brain. Methods Mol Biol. 2011;670:33–44, doi:10.1007/978–1–60761–744–0_3.
- Glabe CG. Structural classification of toxic amyloid oligomers. J Biol Chem. 2008;283:29639–43, doi:10.1074/jbc.R800016200.
- Shankar GM, et al. Biochemical and immunohistochemical analysis of an Alzheimer's disease mouse model reveals the presence of multiple cerebral Abeta assembly forms throughout life. Neurobiol Dis. 2009;36:293–302, doi:10.1016/j.nbd.2009.07.021.
- Mucke L, et al. High-level neuronal expression of abeta 1–42 in wild-type human amyloid protein precursor transgenic mice: synaptotoxicity without plaque formation. J Neurosci. 2000;20:4050–8.
- Hsiao K, et al. Correlative memory deficits, Abeta elevation, and amyloid plaques in transgenic mice. Science. 1996;274:99–102.
- Kawarabayashi T, et al. Age-dependent changes in brain, CSF, and plasma amyloid (beta) protein in the Tg2576 transgenic mouse model of Alzheimer's disease. J Neurosci. 2001;21:372–81.
- Meilandt WJ, et al. Neprilysin overexpression inhibits plaque formation but fails to reduce pathogenic Abeta oligomers and associated cognitive deficits in human amyloid precursor protein transgenic mice. J Neurosci. 2009;29:1977–86, doi:10.1523/JNEUROSCI.2984–08.2009.
- Tomiyama T, et al. A mouse model of amyloid beta oligomers: their contribution to synaptic alteration, abnormal tau phosphorylation, glial activation, and neuronal loss in vivo. J Neurosci. 2010;30:4845–56, doi:10.1523/JNEUROSCI.5825–09.2010.
- Tomiyama T, et al. A new amyloid beta variant favoring oligomerization in Alzheimer's-type dementia. Ann Neurol. 2008;63:377–87, doi:10.1002/ana.21321.
- Lambert MP, et al. Monoclonal antibodies that target pathological assemblies of Abeta. J Neurochem. 2007;100:23–35, doi:10.1111/j.1471–4159.2006.04157.x.
- Larson M, et al. The complex PrP(c)-Fyn couples human oligomeric Abeta with pathological tau changes in Alzheimer's disease. J Neurosci. 2012;32:16857–71a, doi:10.1523/JNEUROSCI.1858–12.2012.
- Podlisny MB, et al. Oligomerization of endogenous and synthetic amyloid beta-protein at nanomolar levels in cell culture and stabilization of monomer by Congo red. Biochemistry. 1998;37:3602–11, doi:10.1021/bi972029u.
- Portelius E, et al. Mass spectrometric characterization of amyloid-beta species in the 7PA2 cell model of Alzheimer's disease. J Alzheimers Dis. 2013 ;33:85–93, doi:10.3233/JAD-2012–120994.
- Welzel AT, et al. Secreted Amyloid beta-Proteins in a Cell Culture Model Include N-Terminally Extended Peptides That Impair Synaptic Plasticity. Biochemistry. 2014;doi:10.1021/bi5003053.
- O'Nuallain B, et al. Amyloid beta-protein dimers rapidly form stable synaptotoxic protofibrils. J Neurosci. 2010;30:14411–9, doi:10.1523/JNEUROSCI.3537–10.2010.
- Tsigelny IF, et al. Structural diversity of Alzheimer's disease amyloid-beta dimers and their role in oligomerization and fibril formation. J Alzheimers Dis. 2014;39:583–600, doi:10.3233/JAD-131589.
- Ma H, et al. Involvement of beta-site APP cleaving enzyme 1 (BACE1) in amyloid precursor protein-mediated enhancement of memory and activity-dependent synaptic plasticity. Proc Natl Acad Sci U S A. 2007;104:8167–72, doi:10.1073/pnas.0609521104.
- Kawarabayashi T et al. Age-dependent changes in brain, CSF, and plasma amyloid (beta) protein in the Tg2576 transgenic mouse model of Alzheimer's disease. J Neurosci. 2001;21:372–81.
- Cheng IH, et al. Accelerating amyloid-beta fibrillization reduces oligomer levels and functional deficits in Alzheimer disease mouse models. J Biol Chem. 2007;282:23818–28, doi:10.1074/jbc.M701078200.
- Oddo S, et al. Reduction of soluble Abeta and tau, but not soluble Abeta alone, ameliorates cognitive decline in transgenic mice with plaques and tangles. J Biol Chem. 2006;281:39413–23, doi:10.1074/jbc.M608485200.
- Fowler SW, et al. Genetic modulation of soluble abeta rescues cognitive and synaptic impairment in a mouse model of Alzheimer's disease. J Neurosci. 2014;34:7871–85, doi:10.1523/JNEUROSCI.0572–14.2014.
- Sherman MA & Lesne SE. Detecting abeta*56 oligomers in brain tissues. Methods Mol Biol. 2011;670:45–56, doi:10.1007/978–1–60761–744–0_4.
- Jack CR, Jr. et al. Tracking pathophysiological processes in Alzheimer's disease: an updated hypothetical model of dynamic biomarkers. Lancet neurology. 2013;12:207–16, doi:10.1016/S1474–4422(12)70291–0.
- Salthouse TA. When does age-related cognitive decline begin? Neurobiology of aging. 2009;30:507–14, doi:10.1016/j.neurobiolaging.2008.09.023.
- Singh-Manoux A, et al. Timing of onset of cognitive decline: results from Whitehall II prospective cohort study. Bmj. 2012;344 :d7622, doi:10.1136/bmj.d7622.
- Lambert MP, et al. Diffusible, nonfibrillar ligands derived from Abeta1–42 are potent central nervous system neurotoxins. Proc Natl Acad Sci U S A. 1998;95:6448–53.
- Lesne SE. Breaking the Code of Amyloid- Oligomers. Int J Cell Biol. 2013;2013:950783, doi:10.1155/2013/950783.