Abstract
The spreading of misfolded protein species contributes to the propagation of harmful mediators in proteinopathies, including Alzheimer’s disease (AD). Cellular stress circumstances, such as abnormal protein accumulation or nutrient deprivation, elicit the secretion of soluble misprocessed proteins and insoluble aggregates via multiple mechanisms of unconventional secretion. One of them consists in the rerouting of autophagic vacuoles towards exocytosis, an unconventional type of autophagy mediated by caspase-3 activation under starvation. Ischemic injury is a starvation condition characterized by oxygen/nutrient deprivation, whose contribution in AD onset has definitely been endorsed. Thus, we investigated the effect of oxygen–glucose deprivation (OGD), an experimental condition mimicking cerebral ischemia, in search of alteration in Tau processing and secretion in hippocampal neurons primary cultures. Our results showed that OGD caused alterations in Tau phosphorylation and processing, paralleled by an induction of its secretion. Interestingly, together with caspase-3 activation, full-length (FL) and fragmented Tau forms were secreted by their own or through a heterogeneous population of microvesicles (MVs), including autophagosome marker LC3-positive vesicles. Accordingly, confocal microscopy revealed a partial colocalization of intracellular Tau and LC3. Summarizing, our findings indicate that OGD alters Tau intracellular levels and protein processing. Consequently, Tau clearance was stimulated through multiple mechanisms related to unconventional Tau secretion, including exophagy. However, the activation of this response represent a double edge sword, because it could contribute to the spreading of misfolded Tau, a neurodegeneration pathway in AD and other tauopathies.
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References
Berne BJ, Pecora R (2000) Dynamic light scattering. Dover Publications, New York
Borges FT, Reis LA, Schor N (2013) Extracellular vesicles: structure, function, and potential clinical uses in renal diseases. Braz J Med Biol Res 46(10):824–830. https://doi.org/10.1590/1414-431X20132964
Brewer GJ, Torricelli JR, Evege EK, Price PJ (1993) Optimized survival of hippocampal neurons in B27-supplemented Neurobasal, a new serum-free medium combination. J Neurosci Res 35(5):567–576
Bulbarelli A, Lonati E, Brambilla A, Orlando A, Cazzaniga E, Piazza F, Ferrarese C, Masserini M, Sancini G (2012) Aβ production in brain capillary endothelial cells after oxygen and glucose deprivation. Mol Cell Neurosci 49:415–422. https://doi.org/10.1016/j.mcn.2012.01.007.
Cailhier JF, Sirois I, Laplante P, Lepage S, Raymond MA, Brassard N, Prat A, Iozzo RV, Pshezhetsky AV, Hébert MJ (2008) Caspase-3 activation triggers extracellular cathepsin L release and endorepellin proteolysis. J Biol Chem 283(40):27220–27229. https://doi.org/10.1074/jbc.M801164200.
Cocucci E, Meldolesi J (2015) Ectosomes and exosomes: shedding the confusion between extracellular vesicles. Trends Cell Biol 25(6):364–372. https://doi.org/10.1016/j.tcb.2015.01.004
Costes SV, Daelemans D, Cho EH, Dobbin Z, Pavlakis G, Lockett S (2004) Automatic and quantitative measurement of protein-protein colocalization in live cells. Biophys J 86(6):3993–4003
Dujardin S, Bégard S, Caillierez R, Lachaud C, Delattre L, Carrier S, Loyens A, Galas MC, Bousset L, Melki R, Aurégan G, Hantraye P, Brouillet E, Buée L, Colin M (2014) Ectosomes: a new mechanism for non-exosomal secretion of tau protein. PLoS One 9(6):e100760. https://doi.org/10.1371/journal.pone.0100760
Eskelinen EL, Prescott AR, Cooper J, Brachmann SM, Wang L, Tang X, Backer JM, Lucocq JM (2002) Inhibition of autophagy in mitotic animal cells. Traffic 3:878–893
Feeney EJ, Spampanato C, Puertollano R, Ballabio A, Parenti G, Raben N (2013) What else is in store for autophagy? Exocytosis of autolysosomes as a mechanism of TFEB-mediated cellular clearance in Pompe disease. Autophagy 9(7):1117–1118. https://doi.org/10.4161/auto.24920
Frisken BJ (2001) Revisiting the method of cumulants for the analysis of dynamic light-scattering data. Appl Opt 40:4087–4091. https://doi.org/10.1364/AO.40.004087
Garnier P, Prigent-Tessier A, Van Hoecke M, Bertrand N, Demougeot C, Sordet O, Swanson RA, Marie C, Beley A (2004) Hypoxia induces caspase-9 and caspase-3 activation without neuronal death in gerbil brains. Eur J Neurosci 20(4):937–946
Gendreau KL, Hall GF (2013) Tangles, toxicity, and tau secretion in AD—new approaches to a vexing problem. Front Neurol 4:160. https://doi.org/10.3389/fneur.2013.00160
György B, Szabó TG, Pásztói M, Pál Z, Misják P, Aradi B, László V, Pállinger E, Pap E, Kittel A, Nagy G, Falus A, Buzás EI (2011) Membrane vesicles, current state-of-the-art: emerging role of extracellular vesicles. Cell Mol Life Sci 68(16):2667–2688. https://doi.org/10.1007/s00018-011-0689-3
Hall GF, Saman S (2012) Death or secretion? The demise of a plausible assumption about CSF-tau in Alzheimer disease? Commun Integr Biol 5(6):623–626. https://doi.org/10.4161/cib.21437
Hamano T, Gendron TF, Causevic E, Yen SH, Lin WL, Isidoro C, Deture M, Ko LW (2008) Autophagic-lysosomal perturbation enhances tau aggregation in transfectants with induced wild-type tau expression. Eur J Neurosci 27(5):1119–1130. https://doi.org/10.1111/j.1460-9568.2008.06084.x
Johnson GV, Seubert P, Cox TM, Motter R, Brown JP, Galasko D (1997) The tau protein in human cerebrospinal fluid in Alzheimer's disease consists of proteolytically derived fragments. J Neurochem 68(1):430–433
Joshi P, Benussi L, Furlan R, Ghidoni R, Verderio C (2015) Extracellular vesicles in Alzheimer’s disease: friends or foes? Focus on aβ-vesicle interaction. Int J Mol Sci 16(3):4800–4813. https://doi.org/10.3390/ijms16034800
Kabeya Y, Mizushima N, Ueno T, Yamamoto A, Kirisako T, Noda T, Kominami E, Ohsumi Y, Yoshimori T (2000) LC3, a mammalian homologue of yeast Apg8p, is localized in autophagosome membranes after processing. EMBO J 19:5720–5728
Kaushik S, Cuervo AM (2012) Chaperone-mediated autophagy: a unique way to enter the lysosome world. Trends Cell Biol 22(8):407–417. https://doi.org/10.1016/j.tcb.2012.05.006
Lee TH, D'Asti E, Magnus N, Al-Nedawi K, Meehan B, Rak J (2011a) Microvesicles as mediators of intercellular communication in cancer--the emerging science of cellular 'debris'. Semin Immunopathol 33(5):455–467. https://doi.org/10.1007/s00281-011-0250-3
Lee S, Sato Y, Nixon RA (2011b) Lysosomal proteolysis inhibition selectively disrupts axonal transport of degradative organelles and causes an Alzheimer’s-like axonal dystrophy. J Neurosci 31(21):7817–7830. https://doi.org/10.1523/JNEUROSCI.6412-10.2011
Lee S, Kim W, Li Z, Hall GF (2012) Accumulation of vesicle-associated human tau in distal dendrites drives degeneration and tau secretion in an in situ cellular tauopathy model. Int J Alzheimers Dis 2012:172837–172816. https://doi.org/10.1155/2012/172837
Liu C, Gao Y, Barrett J, Hu B (2010) Autophagy and protein aggregation after brain ischemia. J Neurochem 115(1):68–78. https://doi.org/10.1111/j.1471-4159.2010.06905.x
Lonati E, Masserini M, Bulbarelli A (2011) Pin1: a new outlook in Alzheimer’s disease. Curr Alzheimer Res 8(6):615–622
Lonati E, Brambilla A, Milani C, Masserini M, Palestini P, Bulbarelli A (2014a) Pin1, a new player in the fate of HIF-1α degradation: an hypothetical mechanism inside vascular damage as Alzheimer's disease risk factor. Front Cell Neurosci 8:8–1. https://doi.org/10.3389/fncel.2014.00001.
Lonati E, Sala G, Bulbarelli A (2014b) Protein misfolding and accumulation as root cause in neurodegeneration, Austin Alzheimers. J Parkinsons Dis 1(4):10 id1016
Manders EMM, Verbeek FJ, Aten JA (1993) Measurement of co-localization of objects in dual-colour confocal images. J Microsc 169:375–382. https://doi.org/10.1111/j.1365-2818.1993.tb03313.x
Manjithaya R, Subramani S (2011) Autophagy: a broad role in unconventional protein secretion? Trends Cell Biol 21(2):67–73. https://doi.org/10.1016/j.tcb.2010.09.009
Mohamed NV, Plouffe V, Rémillard-Labrosse G, Planel E, Leclerc N (2014) Starvation and inhibition of lysosomal function increased tau secretion by primary cortical neurons. Sci Rep 4:5715. https://doi.org/10.1038/srep05715
Morris M, Maeda S, Vossel K, Mucke L (2011) The many faces of tau. Neuron 70:410–426. https://doi.org/10.1016/j.neuron.2011.04.009
Nickel W, Rabouille C (2009) Mechanisms of regulated unconventional protein secretion. Nat Rev Mol Cell Biol 10(2):148–155. https://doi.org/10.1038/nrm2617
Petrucelli L, Dickson D, Kehoe K, Taylor J, Snyder H, Grover A, De Lucia M, McGowan E, Lewis J, Prihar G, Kim J, Dillmann WH, Browne SE, Hall A, Voellmy R, Tsuboi Y, Dawson TM, Wolozin B, Hardy J, Hutton M (2004) CHIP and Hsp70 regulate tau ubiquitination, degradation and aggregation. Hum Mol Genet 13(7):703–714
Plouffe V, Mohamed NV, Rivest-McGraw J, Bertrand J, Lauzon M, Leclerc N (2012) Hyperphosphorylation and cleavage at D421 enhance tau secretion. PLoS One 7(5):e36873. https://doi.org/10.1371/journal.pone.0036873
Portelius E, Hansson SF, Tran AJ, Zetterberg H, Grognet P, Vanmechelen E, Höglund K, Brinkmalm G, Westman-Brinkmalm A, Nordhoff E, Blennow K, Gobom J (2008) Characterization of tau in cerebrospinal fluid using mass spectrometry. J Proteome Res 7(5):2114–2120. https://doi.org/10.1021/pr7008669
Raimondo F, Corbetta S, Morosi L, Chinello C, Gianazza E, Castoldi G, Di Gioia C, Bombardi C, Stella A, Battaglia C, Bianchi C, Magni F, Pitto M (2013) Urinary exosomes and diabetic nephropathy: a proteomic approach. Mol BioSyst 9(6):1139–1146. https://doi.org/10.1039/c2mb25396h
Saman S, Kim W, Raya M, Visnick Y, Miro S, Saman S, Jackson B, McKee AC, Alvarez VE, Lee NC, Hall GF (2012) Exosome-associated tau is secreted in tauopathy models and is selectively phosphorylated in cerebrospinalfluid in early Alzheimer disease. J Biol Chem 287(6):3842–3849. https://doi.org/10.1074/jbc.M111.277061
Simón D, García-García E, Royo F, Falcón-Pérez JM, Avila J (2012a) Proteostasis of tau. Tau overexpression results in its secretion via membrane vesicles. FEBS Lett 586(1):47–54. https://doi.org/10.1016/j.febslet.2011.11.022
Simón D, García-García E, Gómez-Ramos A, Falcón-Pérez JM, Díaz-Hernández M, Hernández F, Avila J (2012b) Tau overexpression results in its secretion via membrane vesicles. Neurodegener Dis 10(1–4):73–75. https://doi.org/10.1159/000334915
Sirois I, Groleau J, Pallet N, Brassard N, Hamelin K, Londono I, Pshezhetsky AV, Bendayan M, Hébert MJ (2012) Caspase activation regulates the extracellular export of autophagic vacuoles. Autophagy 8(6):927–937. https://doi.org/10.4161/auto.19768
Wang Y, Martinez-Vicente M, Krüger U, Kaushik S, Wong E, Mandelkow EM, Cuervo AM, Mandelkow E (2009) Tau fragmentation, aggregation and clearance: the dual role of lysosomal processing. Hum Mol Genet 18(21):4153–4170. https://doi.org/10.1093/hmg/ddp367
Xu F, Gu J-H, Qin Z-H (2012) Neuronal autophagy in cerebral ischemia. Neurosci Bull 28(5):658–666. https://doi.org/10.1007/s12264-012-1268-9
Yuyama K, Sun H, Usuki S, Sakai S, Hanamatsu H, Mioka T, Kimura N, Okada M, Tahara H, Furukawa J, Fujitani N, Shinohara Y, Igarashi Y (2015) A potential function for neuronal exosomes: sequestering intracerebral amyloid-β peptide. FEBS Lett 589(1):84–88. https://doi.org/10.1016/j.febslet.2014.11.027
Zhang M, Schekman R (2013) Cell biology. Unconventional secretion, unconventional solutions. Science 340(6132):559–561. https://doi.org/10.1126/science.1234740.
Zhang M, Kenny SJ, Ge L, Xu K, Schekman R (2015) Translocation of interleukin-1β into a vesicle intermediate in autophagy-mediated secretion. elife 4:e11205. https://doi.org/10.7554/eLife.11205
Acknowledgements
We are grateful to Dr. Sara Redaelli and Dr. Mario Mauri for methodology support.
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This work is financially supported by grants from FAR 2012, FAR 2013, University of Milano-Bicocca.
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About animal welfare, this study was based on protocols (AB12/2012) accepted by Italian Ministry of Health (DL 116/92) and by the Veterinarian Responsible for animal care of Medical School (Milano-Bicocca).
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Lonati, E., Sala, G., Tresoldi, V. et al. Ischemic Conditions Affect Rerouting of Tau Protein Levels: Evidences for Alteration in Tau Processing and Secretion in Hippocampal Neurons. J Mol Neurosci 66, 604–616 (2018). https://doi.org/10.1007/s12031-018-1199-7
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DOI: https://doi.org/10.1007/s12031-018-1199-7