Fluid transport in the perivascular space by the glia-lymphatic (glymphatic) system is important for the removal of solutes from the brain parenchyma, including peptides such as amyloid-beta which are implicated in the pathogenesis of Alzheimer's disease. The glymphatic system is highly active in the sleep state and under the influence of certain of anaesthetics, while it is suppressed in the awake state and by other anaesthetics. Here we investigated whether light sheet fluorescence microscopy of whole optically cleared murine brains was capable of detecting glymphatic differences in sleep- and awake-mimicking anaesthesia, respectively. Using light-sheet imaging of whole brains, we found anaesthetic-dependent cerebrospinal fluid (CSF) influx differences, including reduced tracer influx along tertiary branches of the middle cerebral artery and reduced influx along dorsal and anterior penetrating arterioles, in the awake-mimicking anaesthesia. This study establishes that light sheet microscopy of optically cleared brains is feasible for quantitative analyses and can provide images of the entire glymphatic system in whole brains.

Department of Experimental Medical Science Lund University Lund Sweden

Department of Neurology University Hospital Brno Brno Czech Republic

Developmental and Regenerative Neurobiology Wallenberg Neuroscience Center Lund University Lund Sweden

Wallenberg Centre for Molecular Medicine Lund University Lund Sweden

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Palop JJ, Mucke L.Amyloid-Β-induced neuronal dysfunction in Alzheimer’s disease: from synapses toward neural networks. Nat Neurosci 2010; 13: 812–818. PubMed PMC

Ballatore C, Lee VMY, Trojanowski JQ.Tau-mediated neurodegeneration in Alzheimer’s disease and related disorders. Nat Rev Neurosci 2007; 8: 663–672. PubMed

Goedert M.Alpha-synuclein and neurodegenerative diseases. Nat Rev Neurosci 2001; 2: 492–501. PubMed

Ibanez P, Bonnet A, Débarges B, et al.. Causal relation between alpha-synuclein gene duplication and familial Parkinson’s disease. Lancet 2004; 364: 1169–1171. PubMed

Hardy J, Selkoe D.The amyloid hypothesis of Alzheimer’s disease: progress and problems on the road to therapeutics. Science 2002; 297: 353–356. PubMed

Mawuenyega KG, Sigurdson W, Ovod V, et al.. Decreased clearance of CNS β-amyloid in Alzheimer’s disease. Science 2010; 330: 1774. PubMed PMC

Tarasoff-Conway JM, Carare RO, Osorio RS, et al.. Clearance systems in the brain – implications for Alzheimer disease. Nat Rev Neurol 2015; 11: 457–470. PubMed PMC

Bateman RJ, Munsell LY, Morris JC, et al.. Human amyloid-β synthesis and clearance rates as measured in cerebrospinal fluid in vivo. Nat Med 2006; 12: 856–861. PubMed PMC

Kang J-E, Lim MM, Bateman RJ, et al.. Orexin and the sleep-wake cycle. Science 2009; 326: 1005–1008. PubMed PMC

Roberts KF, Elbert DL, Kasten TP, et al.. Amyloid-β efflux from the central nervous system into the plasma. Ann Neurol 2014; 76: 837–844. PubMed PMC

Pitschke M, Prior R, Haupt M, et al.. Detection of single amyloid β-protein aggregates in the cerebrospinal fluid of Alzheirner’s patients by fluorescence correlation spectroscopy. Nat Med 1998; 4: 832–834. PubMed

Palmqvist S, Zetterberg H, Mattsson N, et al.. Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease. Neurology 2015; 85: 1240–1249. PubMed PMC

Portelius E, Zetterberg H, Andreasson U, et al.. An Alzheimer’s disease-specific β-amyloid fragment signature in cerebrospinal fluid. Neurosci Lett 2006; 409: 215–219. PubMed

Nedergaard M.Garbage truck of the brain. Science 2013; 340: 1529–1530. PubMed PMC

Lundgaard I, Lu ML, Yang E, et al.. Glymphatic clearance controls state-dependent changes in brain lactate concentration. J Cereb Blood Flow Metab 2017; 37: 2112–2124. PubMed PMC

Iliff JJ, Wang M, Liao Y, et al.. A paravascular pathway facilitates CSF flow through the brain parenchyma and the clearance of interstitial solutes, including amyloid β. Sci Transl Med 2012; 4: 147ra111. PubMed PMC

Kress BT, Iliff JJ, Xia M, et al.. Impairment of paravascular clearance pathways in the aging brain. Ann Neurol 2014; 76: 845–861. PubMed PMC

Nakada T, Kwee IL, Igarashi H, et al.. Aquaporin-4 functionality and Virchow-Robin space water dynamics: physiological model for neurovascular coupling and glymphatic flow. Int J Mol Sci 2017; 18: 1798. PubMed PMC

Mestre H, Hablitz LM, Xavier ALR, et al.. Aquaporin-4-dependent glymphatic solute transport in the rodent brain. Elife 2018; 7: 1–31. PubMed PMC

Munk AS, Wang W, Bèchet NB, et al.. PDGF-B is required for development of the glymphatic system. Cell Rep 2019; 26: 2955–2969.e3. PubMed PMC

Lindblom P, Gerhardt H, Liebner S, et al.. Endothelial PDGF-B retention is required for proper investment of pericytes in the microvessel wall. Genes Dev 2003; 17: 1835–1840. PubMed PMC

Abramsson A, Lindblom P, Betsholtz C.Endothelial and nonendothelial sources of PDGF-B regulate pericyte recruitment and influence vascular pattern formation in tumors. J Clin Invest 2003; 112: 1142–1151. PubMed PMC

Mestre H, Tithof J, Du T, et al.. Flow of cerebrospinal fluid is driven by arterial pulsations and is reduced in hypertension. Nat Commun 2018; 9: 4878. PubMed PMC

Hablitz LM, Vinitsky HS, Sun Q, et al.. Increased glymphatic influx is correlated with high EEG delta power and low heart rate in mice under anesthesia. Sci Adv 2019; 5: eaav5447. PubMed PMC

Xie L, Kang H.Xu Q, et al.. Sleep drives metabolite clearance from the adult brain. Science 2013; 342: 373–378. PubMed PMC

Ding F, O’donnell J, Xu Q, et al.. Changes in the composition of brain interstitial ions control the sleep-wake cycle. Science 2016; 352: 550–555. PubMed PMC

Holstein-rathlou S Von, Caesar N, Nedergaard M.Neuroscience Letters Voluntary running enhances glymphatic in flux in awake behaving, young mice. Neurosci Lett 2018; 662: 253–258. PubMed PMC

He XF, Liu DX, Zhang Q, et al.. Voluntary exercise promotes glymphatic clearance of amyloid beta and reduces the activation of astrocytes and microglia in aged mice. Front Mol Neurosci 2017; 10: 1–14. PubMed PMC

Benveniste H, Lee H, Ding F, et al.. Anesthesia with dexmedetomidine and low-dose isoflurane increases solute transport via the glymphatic pathway in rat brain when compared with high-dose isoflurane. Anesthesiology 2017; 127: 976–988. PubMed PMC

Ma Q, Decker Y, Müller A, et al.. Clearance of cerebrospinal fluid from the sacral spine through lymphatic vessels. J Exp Med 2019; 216: 2492–2502. PubMed PMC

Eide PK, Ringstad G.MRI with intrathecal MRI gadolinium contrast medium administration: a possible method to assess glymphatic function in human brain. Acta Radiol Open 2015; 4: 2058460115609635. PubMed PMC

Eide K, Are S, Vatnehol S, et al.. Magnetic resonance imaging provides evidence of glymphatic drainage from human brain to cervical lymph nodes. Sci Rep 2018; 8: 1–10. PubMed PMC

Ringstad G, Valnes LM, Dale AM, et al.. Brain-wide glymphatic enhancement and clearance in humans assessed with MRI. JCI Insight 2018; 3: e121537. PubMed PMC

Iliff JJ, Lee H, Yu M, et al.. Brain-wide pathway for waste clearance captured by contrast-enhanced MRI. J Clin Invest 2013; 123: 1299–1309. PubMed PMC

Plog BA, Mestre H, Olveda GE, et al.. Transcranial optical imaging reveals a pathway for optimizing the delivery of immunotherapeutics to the brain. JCI Insight 2018; 3: 1–15. PubMed PMC

Lundgaard I, Wang W, Eberhardt A, et al.. Beneficial effects of low alcohol exposure, but adverse effects of high alcohol intake on glymphatic function. Sci Rep 2018; 8: 1–16. PubMed PMC

Xavier ALR, Hauglund NL, von Holstein-Rathlou S, et al.. Cannula implantation into the cisterna magna of rodents. J Vis Exp 2018; e57378. PubMed PMC

Ertürk A, Bradke F.High-resolution imaging of entire organs by 3-dimensional imaging of solvent cleared organs (3DISCO). Exp Neurol 2013; 242: 57–64. PubMed

Renier N, Adams EL, Kirst C, et al.. Mapping of brain activity by automated volume analysis of immediate early genes. Cell 2016; 165: 1789–1802. PubMed PMC

Pan C, Cai R, Quacquarelli FP, et al.. Shrinkage-mediated imaging of entire organs and organisms using uDISCO. Nat Methods 2016; 13: 859–867. PubMed

Cai R, Pan C, Ghasemigharagoz A, et al.. Panoptic imaging of transparent mice reveals whole-body neuronal projections and skull–meninges connections. Nat Neurosci 2019; 22: 317–327. PubMed PMC

Schindelin J, Arganda-Carreras I, Frise E, et al.. Fiji: an open-source platform for biological-image analysis. Nat Methods 2012; 9: 676–682. PubMed PMC

Jiang Q, Zhang L, Ding G, et al.. Impairment of the glymphatic system after diabetes. J Cereb Blood Flow Metab 2017; 37: 1326–1337. PubMed PMC