Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Astrocytic adenosine receptor A2A and Gs-coupled signaling regulate memory

Abstract

Astrocytes express a variety of G protein–coupled receptors and might influence cognitive functions, such as learning and memory. However, the roles of astrocytic Gs-coupled receptors in cognitive function are not known. We found that humans with Alzheimer's disease (AD) had increased levels of the Gs-coupled adenosine receptor A2A in astrocytes. Conditional genetic removal of these receptors enhanced long-term memory in young and aging mice and increased the levels of Arc (also known as Arg3.1), an immediate-early gene that is required for long-term memory. Chemogenetic activation of astrocytic Gs-coupled signaling reduced long-term memory in mice without affecting learning. Like humans with AD, aging mice expressing human amyloid precursor protein (hAPP) showed increased levels of astrocytic A2A receptors. Conditional genetic removal of these receptors enhanced memory in aging hAPP mice. Together, these findings establish a regulatory role for astrocytic Gs-coupled receptors in memory and suggest that AD-linked increases in astrocytic A2A receptor levels contribute to memory loss.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Astrocytic A2A receptor expression is increased in humans with AD.
Figure 2: Conditional ablation of A2A receptors in astrocytes enhances memory in mice.
Figure 3: Generation of GFAP-Rs1 transgenic mice.
Figure 4: Rs1 ligand increases Gs-coupled signaling in Rs1-expressing astrocytes.
Figure 5: Rs1 ligand impairs memory in GFAP-Rs1 mice.
Figure 6: Untreated young and aging GFAP-Rs1 mice have reduced memory.
Figure 7: Astrocytic A2A receptor levels are increased in transgenic mice expressing mutant forms of hAPP alone or in combination with a mutant form of PS1.
Figure 8: Conditional ablation of A2A receptors reduces memory deficits in aging hAPP mice.

Similar content being viewed by others

References

  1. Fredholm, B.B., IJzerman, A.P., Jacobson, K.A., Klotz, K.N. & Linden, J. International Union of Pharmacology. XXV. Nomenclature and classification of adenosine receptors. Pharmacol. Rev. 53, 527–552 (2001).

    CAS  PubMed  Google Scholar 

  2. Burnstock, G. Physiology and pathophysiology of purinergic neurotransmission. Physiol. Rev. 87, 659–797 (2007).

    CAS  PubMed  Google Scholar 

  3. Bogenpohl, J.W., Ritter, S.L., Hall, R.A. & Smith, Y. Adenosine A2A receptor in the monkey basal ganglia: ultrastructural localization and colocalization with the metabotropic glutamate receptor 5 in the striatum. J. Comp. Neurol. 520, 570–589 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  4. Chen, J.F. et al. Adenosine A2A receptors and brain injury: broad spectrum of neuroprotection, multifaceted actions and “fine tuning” modulation. Prog. Neurobiol. 83, 310–331 (2007).

    CAS  PubMed  Google Scholar 

  5. Saura, J. et al. Adenosine A2A receptor stimulation potentiates nitric oxide release by activated microglia. J. Neurochem. 95, 919–929 (2005).

    CAS  PubMed  Google Scholar 

  6. Orr, A.G., Orr, A.L., Li, X.J., Gross, R.E. & Traynelis, S.F. Adenosine A(2A) receptor mediates microglial process retraction. Nat. Neurosci. 12, 872–878 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  7. Matos, M., Augusto, E., Agostinho, P., Cunha, R.A. & Chen, J.F. Antagonistic interaction between Adenosine A2A receptors and Na+/K+-ATPase-alpha2 controlling glutamate uptake in astrocytes. J. Neurosci. 33, 18492–18502 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  8. Albasanz, J.L., Perez, S., Barrachina, M., Ferrer, I. & Martin, M. Up-regulation of adenosine receptors in the frontal cortex in Alzheimer's disease. Brain Pathol. 18, 211–219 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  9. Laurent, C. et al. A2A adenosine receptor deletion is protective in a mouse model of Tauopathy. Mol. Psychiatry published online, 10.1038/mp.2014.151 (2 December 2014).

  10. Huang, Y. & Mucke, L. Alzheimer mechanisms and therapeutic strategies. Cell 148, 1204–1222 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  11. Heneka, M.T. & O'Banion, M.K. Inflammatory processes in Alzheimer's disease. J. Neuroimmunol. 184, 69–91 (2007).

    CAS  PubMed  Google Scholar 

  12. Braak, H. & Braak, E. Staging of Alzheimer's disease-related neurofibrillary changes. Neurobiol. Aging 16, 271–278 (1995).

    CAS  PubMed  Google Scholar 

  13. Cahoy, J.D. et al. A transcriptome database for astrocytes, neurons and oligodendrocytes: a new resource for understanding brain development and function. J. Neurosci. 28, 264–278 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  14. Pickel, V.M., Chan, J., Linden, J. & Rosin, D.L. Subcellular distributions of adenosine A1 and A2A receptors in the rat dorsomedial nucleus of the solitary tract at the level of the area postrema. Synapse 60, 496–509 (2006).

    CAS  PubMed  Google Scholar 

  15. Lazarus, M. et al. Arousal effect of caffeine depends on adenosine A2A receptors in the shell of the nucleus accumbens. J. Neurosci. 31, 10067–10075 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  16. Bajenaru, M.L. et al. Astrocyte-specific inactivation of the neurofibromatosis 1 gene (NF1) is insufficient for astrocytoma formation. Mol. Cell. Biol. 22, 5100–5113 (2002).

    CAS  PubMed  PubMed Central  Google Scholar 

  17. Fox, I.J. et al. Developmental expression of glial fibrillary acidic protein mRNA in mouse forebrain germinal zones: implications for stem cell biology. Brain Res. Dev. Brain Res. 153, 121–125 (2004).

    CAS  PubMed  Google Scholar 

  18. Karasinska, J.M. et al. ABCA1 influences neuroinflammation and neuronal death. Neurobiol. Dis. 54, 445–455 (2013).

    CAS  PubMed  Google Scholar 

  19. Stenzel, D. et al. Integrin-dependent and -independent functions of astrocytic fibronectin in retinal angiogenesis. Development 138, 4451–4463 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  20. Yamanaka, K. et al. Astrocytes as determinants of disease progression in inherited amyotrophic lateral sclerosis. Nat. Neurosci. 11, 251–253 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  21. Garcia, A.D., Doan, N.B., Imura, T., Bush, T.G. & Sofroniew, M.V. GFAP-expressing progenitors are the principal source of constitutive neurogenesis in adult mouse forebrain. Nat. Neurosci. 7, 1233–1241 (2004).

    CAS  PubMed  Google Scholar 

  22. Matos, M. et al. Adenosine A2A receptors modulate glutamate uptake in cultured astrocytes and gliosomes. Glia 60, 702–716 (2012).

    PubMed  Google Scholar 

  23. Rebola, N., Lujan, R., Cunha, R.A. & Mulle, C. Adenosine A2A receptors are essential for long-term potentiation of NMDA-EPSCs at hippocampal mossy fiber synapses. Neuron 57, 121–134 (2008).

    CAS  PubMed  Google Scholar 

  24. Vianna, M.R. et al. Role of hippocampal signaling pathways in long-term memory formation of a nonassociative learning task in the rat. Learn. Mem. 7, 333–340 (2000).

    CAS  PubMed  PubMed Central  Google Scholar 

  25. Ledent, C. et al. Aggressiveness, hypoalgesia and high blood pressure in mice lacking the adenosine A2a receptor. Nature 388, 674–678 (1997).

    CAS  PubMed  Google Scholar 

  26. Bastia, E. et al. A crucial role for forebrain adenosine A(2A) receptors in amphetamine sensitization. Neuropsychopharmacology 30, 891–900 (2005).

    CAS  PubMed  Google Scholar 

  27. O'Callaghan, J.P. & Miller, D.B. The concentration of glial fibrillary acidic protein increases with age in the mouse and rat brain. Neurobiol. Aging 12, 171–174 (1991).

    CAS  PubMed  Google Scholar 

  28. Wimmer, M.E., Hernandez, P.J., Blackwell, J. & Abel, T. Aging impairs hippocampus-dependent long-term memory for object location in mice. Neurobiol. Aging 33, 2220–2224 (2012).

    PubMed  Google Scholar 

  29. Plath, N. et al. Arc/Arg3.1 is essential for the consolidation of synaptic plasticity and memories. Neuron 52, 437–444 (2006).

    CAS  PubMed  Google Scholar 

  30. Alexander, G.M. et al. Remote control of neuronal activity in transgenic mice expressing evolved G protein–coupled receptors. Neuron 63, 27–39 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  31. Chang, W.C. et al. Modifying ligand-induced and constitutive signaling of the human 5-HT4 receptor. PLoS ONE 2, e1317 (2007).

    PubMed  PubMed Central  Google Scholar 

  32. Halassa, M.M., Fellin, T., Takano, H., Dong, J.H. & Haydon, P.G. Synaptic islands defined by the territory of a single astrocyte. J. Neurosci. 27, 6473–6477 (2007).

    CAS  PubMed  PubMed Central  Google Scholar 

  33. Bai, X. et al. Genetic background affects human glial fibrillary acidic protein promoter activity. PLoS ONE 8, e66873 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  34. Han, H.J. et al. Strain background influences neurotoxicity and behavioral abnormalities in mice expressing the tetracycline transactivator. J. Neurosci. 32, 10574–10586 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  35. Tse, D. et al. Schemas and memory consolidation. Science 316, 76–82 (2007).

    CAS  PubMed  Google Scholar 

  36. Mucke, L. et al. High-level neuronal expression of Aβ1–42 in wild-type human amyloid protein precursor transgenic mice: synaptotoxicity without plaque formation. J. Neurosci. 20, 4050–4058 (2000).

    CAS  PubMed  PubMed Central  Google Scholar 

  37. Ji, B. et al. Imaging of peripheral benzodiazepine receptor expression as biomarkers of detrimental versus beneficial glial responses in mouse models of Alzheimer's and other CNS pathologies. J. Neurosci. 28, 12255–12267 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  38. Jankowsky, J.L. et al. Mutant presenilins specifically elevate the levels of the 42 residue beta-amyloid peptide in vivo: evidence for augmentation of a 42-specific gamma secretase. Hum. Mol. Genet. 13, 159–170 (2004).

    CAS  PubMed  Google Scholar 

  39. Yoshiyama, Y. et al. Synapse loss and microglial activation precede tangles in a P301S tauopathy mouse model. Neuron 53, 337–351 (2007).

    CAS  PubMed  Google Scholar 

  40. Sullivan, P.M. et al. Targeted replacement of the mouse apolipoprotein E gene with the common human APOE3 allele enhances diet-induced hypercholesterolemia and atherosclerosis. J. Biol. Chem. 272, 17972–17980 (1997).

    CAS  PubMed  Google Scholar 

  41. Han, J. et al. Acute cannabinoids impair working memory through astroglial CB1 receptor modulation of hippocampal LTD. Cell 148, 1039–1050 (2012).

    CAS  PubMed  Google Scholar 

  42. Suzuki, A. et al. Astrocyte-neuron lactate transport is required for long-term memory formation. Cell 144, 810–823 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  43. Panatier, A. et al. Glia-derived D-serine controls NMDA receptor activity and synaptic memory. Cell 125, 775–784 (2006).

    CAS  PubMed  Google Scholar 

  44. Lee, Y. et al. Oligodendroglia metabolically support axons and contribute to neurodegeneration. Nature 487, 443–448 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  45. Altevogt, B.M. & Paul, D.L. Four classes of intercellular channels between glial cells in the CNS. J. Neurosci. 24, 4313–4323 (2004).

    CAS  PubMed  PubMed Central  Google Scholar 

  46. Dunwiddie, T.V. & Masino, S.A. The role and regulation of adenosine in the central nervous system. Annu. Rev. Neurosci. 24, 31–55 (2001).

    CAS  PubMed  Google Scholar 

  47. Borota, D. et al. Post-study caffeine administration enhances memory consolidation in humans. Nat. Neurosci. 17, 201–203 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  48. Hardt, O., Nader, K. & Nadel, L. Decay happens: the role of active forgetting in memory. Trends Cogn. Sci. 17, 111–120 (2013).

    PubMed  Google Scholar 

  49. Goldman, J.E. & Abramson, B. Cyclic AMP-induced shape changes of astrocytes are accompanied by rapid depolymerization of actin. Brain Res. 528, 189–196 (1990).

    CAS  PubMed  Google Scholar 

  50. Murray, P.D., Kingsbury, T.J. & Krueger, B.K. Failure of Ca2+-activated, CREB-dependent transcription in astrocytes. Glia 57, 828–834 (2009).

    PubMed  PubMed Central  Google Scholar 

  51. Chen, J.F. et al. A(2A) adenosine receptor deficiency attenuates brain injury induced by transient focal ischemia in mice. J. Neurosci. 19, 9192–9200 (1999).

    CAS  PubMed  PubMed Central  Google Scholar 

  52. Lin, W. et al. Interferon-gamma induced medulloblastoma in the developing cerebellum. J. Neurosci. 24, 10074–10083 (2004).

    CAS  PubMed  PubMed Central  Google Scholar 

  53. Conklin, B.R. et al. Engineering GPCR signaling pathways with RASSLs. Nat. Methods 5, 673–678 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  54. Hsiao, E.C. et al. Osteoblast expression of an engineered Gs-coupled receptor dramatically increases bone mass. Proc. Natl. Acad. Sci. USA 105, 1209–1214 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  55. Halassa, M.M. et al. Astrocytic modulation of sleep homeostasis and cognitive consequences of sleep loss. Neuron 61, 213–219 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  56. Sweger, E.J., Casper, K.B., Scearce-Levie, K., Conklin, B.R. & McCarthy, K.D. Development of hydrocephalus in mice expressing the G(i)-coupled GPCR Ro1 RASSL receptor in astrocytes. J. Neurosci. 27, 2309–2317 (2007).

    CAS  PubMed  PubMed Central  Google Scholar 

  57. Pascual, O. et al. Astrocytic purinergic signaling coordinates synaptic networks. Science 310, 113–116 (2005).

    CAS  PubMed  Google Scholar 

  58. Kawamata, H. et al. Abnormal intracellular calcium signaling and SNARE-dependent exocytosis contributes to SOD1G93A astrocyte-mediated toxicity in amyotrophic lateral sclerosis. J. Neurosci. 34, 2331–2348 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  59. Fujita, T. et al. Neuronal transgene expression in dominant-negative SNARE mice. J. Neurosci. 34, 16594–16604 (2014).

    PubMed  PubMed Central  Google Scholar 

  60. Sloan, S.A. & Barres, B.A. Looks can be deceiving: Reconsidering the evidence for gliotransmission. Neuron 84, 1112–1115 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  61. Rockenstein, E.M. et al. Levels and alternative splicing of amyloid beta protein precursor (APP) transcripts in brains of APP transgenic mice and humans with Alzheimer's disease. J. Biol. Chem. 270, 28257–28267 (1995).

    CAS  PubMed  Google Scholar 

  62. Palop, J.J. et al. Aberrant excitatory neuronal activity and compensatory remodeling of inhibitory hippocampal circuits in mouse models of Alzheimer's disease. Neuron 55, 697–711 (2007).

    CAS  PubMed  PubMed Central  Google Scholar 

  63. Sullivan, P.M., Mace, B.E., Maeda, N. & Schmechel, D.E. Marked regional differences of brain human apolipoprotein E expression in targeted replacement mice. Neuroscience 124, 725–733 (2004).

    CAS  PubMed  Google Scholar 

  64. Raber, J. et al. Isoform-specific effects of human apolipoprotein E on brain function revealed in ApoE knockout mice: Increased susceptibility of females. Proc. Natl. Acad. Sci. USA 95, 10914–10919 (1998).

    CAS  PubMed  PubMed Central  Google Scholar 

  65. Leung, L. et al. Apolipoprotein E4 causes age- and sex-dependent impairments of hilar GABAergic interneurons and learning and memory deficits in mice. PLoS ONE 7, e53569 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  66. Colin, A. et al. Engineered lentiviral vector targeting astrocytes in vivo. Glia 57, 667–679 (2009).

    PubMed  Google Scholar 

  67. Shigetomi, E., Kracun, S. & Khakh, B.S. Monitoring astrocyte calcium microdomains with improved membrane targeted GCaMP reporters. Neuron Glia Biol. 6, 183–191 (2010).

    PubMed  PubMed Central  Google Scholar 

  68. Zlatkine, P., Mehul, B. & Magee, A.I. Retargeting of cytosolic proteins to the plasma membrane by the Lck protein tyrosine kinase dual acylation motif. J. Cell Sci. 110, 673–679 (1997).

    CAS  PubMed  Google Scholar 

  69. Hagemann, T.L., Jobe, E.M. & Messing, A. Genetic ablation of Nrf2/antioxidant response pathway in Alexander disease mice reduces hippocampal gliosis but does not impact survival. PLoS ONE 7, e37304 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  70. Saaltink, D.J., Havik, B., Verissimo, C.S., Lucassen, P.J. & Vreugdenhil, E. Doublecortin and doublecortin-like are expressed in overlapping and non–overlapping neuronal cell population: Implications for neurogenesis. J. Comp. Neurol. 520, 2805–2823 (2012).

    PubMed  Google Scholar 

  71. Spencer, B. et al. Beclin 1 gene transfer activates autophagy and ameliorates the neurodegenerative pathology in alpha-synuclein models of Parkinson's and Lewy body diseases. J. Neurosci. 29, 13578–13588 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  72. Marxreiter, F. et al. Glial A30P alpha-synuclein pathology segregates neurogenesis from anxiety-related behavior in conditional transgenic mice. Neurobiol. Dis. 59, 38–51 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  73. Piatti, V.C. et al. The timing for neuronal maturation in the adult hippocampus is modulated by local network activity. J. Neurosci. 31, 7715–7728 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  74. Mangin, J.M., Li, P., Scafidi, J. & Gallo, V. Experience-dependent regulation of NG2 progenitors in the developing barrel cortex. Nat. Neurosci. 15, 1192–1194 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  75. Olabarria, M., Noristani, H.N., Verkhratsky, A. & Rodriguez, J.J. Concomitant astroglial atrophy and astrogliosis in a triple transgenic animal model of Alzheimer's disease. Glia 58, 831–838 (2010).

    PubMed  Google Scholar 

  76. Nicole, O. et al. Activation of protease-activated receptor-1 triggers astrogliosis after brain injury. J. Neurosci. 25, 4319–4329 (2005).

    CAS  PubMed  PubMed Central  Google Scholar 

  77. Moritz, A. et al. Akt-RSK-S6 kinase signaling networks activated by oncogenic receptor tyrosine kinases. Sci. Signal. 3, ra64 (2010).

    PubMed  PubMed Central  Google Scholar 

  78. Terai, K. et al. beta-amyloid deposits in transgenic mice expressing human beta-amyloid precursor protein have the same characteristics as those in Alzheimer's disease. Neuroscience 104, 299–310 (2001).

    CAS  PubMed  Google Scholar 

  79. Kir, S. et al. Tumour-derived PTH-related protein triggers adipose tissue browning and cancer cachexia. Nature 513, 100–104 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  80. Yiu, A.P., Rashid, A.J. & Josselyn, S.A. Increasing CREB function in the CA1 region of dorsal hippocampus rescues the spatial memory deficits in a mouse model of Alzheimer's disease. Neuropsychopharmacology 36, 2169–2186 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  81. Syme, C.A., Friedman, P.A. & Bisello, A. Parathyroid hormone receptor trafficking contributes to the activation of extracellular signal-regulated kinases but is not required for regulation of cAMP signaling. J. Biol. Chem. 280, 11281–11288 (2005).

    CAS  PubMed  Google Scholar 

  82. Sivachandran, N., Sarkari, F. & Frappier, L. Epstein-Barr nuclear antigen 1 contributes to nasopharyngeal carcinoma through disruption of PML nuclear bodies. PLoS Pathog. 4, e1000170 (2008).

    PubMed  PubMed Central  Google Scholar 

  83. Yang, Y. et al. Molecular comparison of GLT1+ and ALDH1L1+ astrocytes in vivo in astroglial reporter mice. Glia 59, 200–207 (2011).

    PubMed  PubMed Central  Google Scholar 

  84. Coppieters, N. et al. Global changes in DNA methylation and hydroxymethylation in Alzheimer's disease human brain. Neurobiol. Aging 35, 1334–1344 (2014).

    CAS  PubMed  Google Scholar 

  85. Kocherhans, S. et al. Reduced Reelin expression accelerates amyloid-beta plaque formation and tau pathology in transgenic Alzheimer's disease mice. J. Neurosci. 30, 9228–9240 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

We thank P.E. Sanchez for advice on behavioral experiments, R. Ponnusamy for comments on the manuscript, J.-F. Chen (Boston University School of Medicine) for providing loxP-Adora2a transgenic mice, N. DĂ©glon (Lausanne University Hospital) for providing the lentiviral vector and packaging plasmids, B. Khakh (University of California, Los Angeles) for providing the plasmid encoding the membrane-targeting region of lck, S.-W. Min and L. Gan (Gladstone Institute of Neurological Disease) for providing brain tissue from Tau-P301S mice, L. Leung and Y. Huang (Gladstone Institute of Neurological Disease) for providing brain tissue from ApoE3-KI and ApoE4-KI mice, A. Lundquist, G. Shlager, C. Wang and E. Whiting for technical support, R. Craft, T. Hamto, I. Lo and B. Masatsugu of the Gladstone Behavioral Core for advice and technical support, and M. Dela Cruz and A. Cheung for administrative assistance. This study was supported by US National Institutes of Health grants AG039220 to A.G.O., AR056299 to E.C.H., AG034531 to D.B.D. HL60664 and HL100406 to B.R.C., and AG022074 and NS065780 to L.M., and a MetLife Foundation Award to L.M. The Gladstone Institutes received support from a National Center for Research Resources Grant RR18938.

Author information

Authors and Affiliations

Authors

Contributions

A.G.O. and L.M. designed and coordinated the study. A.G.O. carried out in vitro assays, immunohistochemistry, western blotting and behavioral testing. E.C.H. and B.R.C. generated TetO-Rs1 transgenic mice and the plasmids encoding Rs1 and provided advice on Rs1 ligands. M.M.W. helped to conduct and analyze behavioral tests. K.H. performed western blotting, immunoprecipitation, immunohistochemistry and mouse perfusions. D.H.K. and D.B.D. performed qRT-PCR. X.W. administered drugs and genotyped and perfused mice. W.G., J.K. and G.-Q.Y. managed mouse lines and performed mouse perfusions. A.A. and E.M. performed immunohistochemistry, helped analyze related data and provided human tissue. N.D. helped design and conduct behavioral tests. A.G.O. and L.M. wrote the manuscript.

Corresponding authors

Correspondence to Anna G Orr or Lennart Mucke.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Integrated supplementary information

Supplementary Figure 1 Transgenic mouse lines used to alter astrocytic gene expression; minimal microglial A2A receptor expression in the human brain.

(a) Schematic of the GFAP-Cre/loxP-Adora2a transgenic system. Cre, Cre recombinase. (b) Schematic of the GFAP-tTA/TetO-Rs1 transgenic system. (c) Table of Rs1 expression and signaling in GFAP-Rs1 mice. (d) Representative photomicrographs of hippocampal sections co-immunolabeled for the A2A receptor (green) and the microglial marker Iba1 (red) from a control (Con) and an AD case. n = 3 cases per disease condition. Scale bar: 50 µm.

Supplementary Figure 2 A2A receptor expression and signaling in primary astrocyte cultures.

(a) Primary astrocyte cultures from wild-type mice were or were not (Con) transduced with lentiviral constructs encoding mCherry (mCher) or the mouse A2A receptor (A2A). Representative cropped western blots show A2A receptor expression in A2A-transduced astrocytes, but not in mCher-transduced or Con astrocytes. The quantity of lentiviral particles (Lenti) used in the cultures is indicated as ng of p24 protein per well. GFAP served as a loading control. n = 2 or more wells per condition from 1–3 independent experiments. (b) Relative cAMP levels in primary astrocyte cultures established from wild-type mice and transduced or not (Con) with lentivirus encoding mCherry (mCh) or the A2A receptor. Cultures were treated for 15 min with vehicle, adenosine (10 µM), or the A2A-selective agonist CGS-21680 (CGS, 10 µM). cAMP levels were normalized to the average levels in vehicle-treated cells within each transduction condition. Two-way ANOVA: F(4, 96) = 22.74, P < 0.0001 for interaction effect. n = 14 Con/Vehicle, 6 Con/Adenosine, 14 Con/CGS, 14 mCh/Vehicle, 6 mCh/Adenosine, 14 mCh/CGS, 16 A2A/Vehicle, 6 A2A/Adenosine, and 15 A2A/CGS wells from two independent experiments. ##P < 0.01, ###P < 0.001 vs. vehicle (Bonferroni test). (c) Intracellular calcium levels. Con or A2A-transduced astrocytes were treated with CGS (10 µM) or ATP (100 µM) as a positive control, and assayed for intracellular calcium levels with Calcium-5. Fluorescence intensities were normalized to the average baseline intensity within each well. Peak intensities were compared between groups. Two-way ANOVA: F(1, 26) = 0.02, P = 0.88 for interaction effect, F(1, 26) = 28.51, P < 0.0001 for agonist effect. n = 8 Con/ATP, 7 Con/CGS, 7 A2A/ATP, and 8 A2A/CGS wells from two independent experiments. (d–e) Phosphorylated (p) and total (t) CREB and ERK levels in primary wild-type astrocytes transduced (d) or not (e) with a lentivirus encoding the A2A receptor and treated with vehicle, CGS (10 µM, 10 min), or forskolin (FSK, 30 µM, 30 min), an activator of adenylate cyclase. Representative cropped western blots and densitometric quantification of western blot signals are shown. Ratios of phosphorylated/total protein were normalized to the average ratios in vehicle-treated cells. Student's t test with Welch's correction (vs. vehicle of matching protein): (d) P = 0.0006 (pCREB), P = 0.042 (pERK). n = 6 Vehicle/pCREB, 10 CGS/pCREB, 6 Vehicle/pERK, and 10 CGS/pERK wells from two independent experiments. (e) P = 0.0008 (pCREB), P = 0.0004 (pERK). n = 7 Vehicle/pCREB, 8 FSK/pCREB, 5 Vehicle/pERK, and 6 FSK/pERK wells from two independent experiments. *P < 0.05, ***P < 0.001 vs. Vehicle (Student's t test). Full-length blots are presented in Supplementary Figure 13. Data are presented as mean ± s.e.m.

Supplementary Figure 3 Preservation of neuronal A2A receptor expression in GFAP-Cre/loxP-Adora2a mice.

(a) Representative photomicrographs of striatal and cortical sections from 12–13-month-old GFAP-Cre/loxP-Adora2a mice and 2-month-old global homozygous A2A receptor knockout mice (A2A-gKO) immunostained for the A2A receptor. Insets (i–iv): magnified views of the boxed regions. Scale bar: 500 µm. n = 3 mice per genotype. (b–c) Representative confocal micrographs (top) and quantitative histological analyses (bottom) of hippocampal CA1 sections from 12–13-month-old wild-type controls (Control) and A2A-cKO mice, and 2-month-old A2A-gKO mice co-immunostained for the A2A receptor (red) and an astrocyte marker (GFAP, green) or a neuronal marker (NeuN). Cell nuclei were labeled with DAPI (blue). Scale bar: 10 µm. One-way ANOVA: (b) F(2, 11) = 8.17, P = 0.0067; (c) F(2, 11) = 83.95, P < 0.0001. n = 5 Con, 6 A2A-cKO and 3 A2A-gKO mice. Data are presented as mean ± s.e.m.

Supplementary Figure 4 Conditional ablation of A2A receptors in astrocytes does not affect swim speed or anxiety behavior.

(a–b) Swim speeds of GFAP-Cre/loxP-Adora2a mice during Morris water maze probe trials corresponding to (a) Figure 2b and (b) Figure 2h. One-way ANOVA: (a) F(2, 43) = 1.83, P = 0.17, n = 12 cWT, 18 cHET, and 17 cKO mice; (b) F(2, 30) = 2.67, P = 0.086, n = 7 cWT, 15 cHET, and 11 cKO mice. P > 0.05 vs. cWT (Dunnett's test). (c–d) GFAP-Cre/loxP-Adora2a mice were assessed in the open field at 2–4 months of age. Average ratios of activity in the center of the field to total activity in the field are shown for trials corresponding to (c) Figure 2c and (d) Figure 2e. Repeated measures two-way ANOVA: (c) F(12, 270) = 0.65, P = 0.80 for interaction effect, F(2, 45) = 0.84, P = 0.44 for genotype effect. n = 12 cWT, 18 cHET, and 17 cKO mice. (d) F(6, 129) = 0.87, P = 0.52 for interaction effect, F(2, 43) = 0.12, P = 0.89 for genotype effect. n = 12 cWT, 18 cHET, and 16 cKO mice. Data are presented as mean ± s.e.m.

Supplementary Figure 5 Conditional ablation of A2A receptors in astrocytes increases baseline Arc levels.

Mice resting in their home cages during their daytime sleep cycle were killed rapidly as described in Methods. (a–b) Number of cells per section (a) and total area per section (b) immunoreactive for Arc in the granular layer of the dentate gyrus (DGgl) of GFAP-Cre/loxP-Adora2a mice at 3–22 months of age. Con: singly transgenic loxP-Adora2a and GFAP-Cre control mice. One-way ANOVA: (a) F(2, 31) = 3.68, P = 0.0367; (b) F(2, 31) = 4.83, P = 0.015. n = 12 Con, 12 cHET, and 10 cKO mice. *P < 0.05, **P < 0.01 vs. Con (Dunnett's test). (c) Levels of Arc mRNA in the visual cortex of GFAP-Cre/loxP-Adora2a mice determined by qRT-PCR at 9–22 months of age. Gapdh mRNA served as a loading control. One-way ANOVA: F(2, 32) = 5.59, P = 0.0083. n = 8 Con, 19 cHET, and 8 cKO mice. **P < 0.01 vs. Con (Dunnett's test). (d–e) Ages of mice shown in a–b (d) and c (e). One-way ANOVA: (d) F(2, 31) = 0.23, P = 0.80; (e) F(2, 32) = 4.24, P = 0.023. P > 0.05 vs. Con (Dunnett's test). Data are presented as mean ± s.e.m.

Supplementary Figure 6 Rs1 expression, normal body weight and unaltered behavioral functions in GFAP-Rs1 mice.

(a–b) Representative photomicrographs of FLAG-immunostained brain sections depicting the hippocampal formation (a) and thalamus (b) of 2–4-month-old TetO-Rs1, GFAP-tTA, and GFAP-Rs1 mice. In contrast to GFAP-Rs1 doubly transgenic mice, TetO-Rs1 or GFAP-tTA singly transgenic mice did not show Rs1 expression. Continuous maintenance of GFAP-Rs1 mice on DOX before and after birth prevented FLAG-Rs1 expression. Scale bars: 200 µm. Insets (i–ii): magnified views of the boxed regions. n = 3 TetO-Rs1, 9 GFAP-tTA, 15 GFAP-Rs1 and 3 GFAP-Rs1/DOX mice. (c–d) Representative photomicrographs of FLAG-immunostained sections depicting the hippocampal formation (c) and thalamus (d) of 20–22-month-old GFAP-Rs1 mice. Scale bar: 200 µm. Insets (iii–iv): magnified views of the boxed regions. n = 7 mice. (e–f) Weight of GFAP-tTA (Con) and GFAP-Rs1 mice at 2–9 (e) and 15–18 (f) months of age. Student's t test (vs. Con of matching sex): (e) P = 0.69 (Females), P = 0.30 (Males); (f) P = 0.71 (Females), P = 0.92 (Males). n = 7 Con females, 9 GFAP-Rs1 females, 8 Con males, and 8 GFAP-Rs1 males (e); n = 28 Con females, 27 GFAP-Rs1 females, 23 Con males, and 19 GFAP-Rs1 males (f). (g–k) Behavioral assessment of GFAP-tTA (Con) and GFAP-Rs1 mice at 2–3 months of age. (g) Rota-Rod test (16 rpm). n = 13 Con and 13 GFAP-Rs1 mice. (h) Open-field test (15-min duration). n = 13 Con and 13 GFAP-Rs1 mice. (i) Hot-plate test. n = 12 Con and 13 GFAP-Rs1 mice. (j–k) Elevated plus maze at 3–5 (j) or 18–19 (k) months of age. n = 13 Con and 13 GFAP-Rs1 mice (j) or 14 Con and 11 GFAP-Rs1 mice (k). Student's t test (vs. Con): (g) P = 0.90; (h) P = 0.34 (Total activity), P = 0.73 (Center/total activity); (i) P = 0.84; (j) P = 0.93; (k) P = 0.50. Data are presented as mean ± s.e.m.

Supplementary Figure 7 Rs1 ligand effects in control and GFAP-Rs1 mice in the Morris Water Maze.

(a–b) Swim speeds of GFAP-tTA (Con), TetO-Rs1 and GFAP-Rs1 mice during probe trials corresponding to (a) Figure 5c and (b) Figure 5i and Supplementary Figure 7e. Student's t test (vs. Saline of matching genotype): (a) P = 0.17 (Con); P = 0.23 (GFAP-Rs1). (b) P = 0.91 (GFAP-tTA); P = 0.54 (TetO-Rs1), P = 0.49 (GFAP-Rs1). n = 27 Con/saline, 28 Con/GR, 18 GFAP-Rs1/saline, and 20 GFAP-Rs1/GR mice (a); n = 19 GFAP-tTA/saline, 18 GFAP-tTA/GR, 14 TetO-Rs1/saline, 18 TetO-Rs1/GR, 16 GFAP-Rs1/saline, and 16 GFAP-Rs1/GR mice (b). (c–e) Rs1 ligand did not impair the performance of TetO-Rs1 singly transgenic mice in the Morris water maze at 2–11 months of age. (c) Experimental design for data in (d–e). TetO-Rs1 mice were trained for two days to locate the hidden platform and injected with saline or GR-125487 (GR, 3 mg/kg, i.p.) one day after training. Memory of the platform location was tested in a probe trial two days after training. (d) Distance traveled to reach the hidden platform during training. Two-way ANOVA: F(1, 30) = 0.01, P = 0.93 for interaction effect; F(1, 30) = 0.02, P = 0.88 for agonist effect. n = 14 TetO-Rs1/saline and 18 TetO-Rs1/GR mice. (e) Probe. Left, crossings. Student's t test with Welch's correction (Target vs. Other): P = 0.047 (Saline), P = 0.0042 (GR). Right, latency to reach target location. One-tailed Student's t test: P = 0.14; n = 14 TetO-Rs1/saline and 18 TetO-Rs1/GR mice. (f–g) Rs1 ligand did not acutely impair memory retrieval in Con and GFAP-Rs1 mice in the Morris water maze at 2–11 months of age. (f) Experimental design for data in (g). Mice were trained for two days to locate the hidden platform. Memory of the platform location was tested in a probe trial two days after training. Mice received an injection of saline or GR-125487 (GR, 3 mg/kg, i.p.) 4 h before the probe trial. (g) Probe. Left, crossings. Two-way ANOVA: F(1, 72) = 0.16, P = 0.69 for genotype by treatment interaction. Student's t test with Welch's correction (Target vs. Other): P = 0.0003 (Con/Saline), P = 0.033 (Con/GR), P < 0.0001 (GFAP-Rs1/Saline), P = 0.008 (GFAP-Rs1/GR). Right, latency to reach target location. Two-way ANOVA: F(1, 72) = 0.35, P = 0.56 for genotype by treatment interaction. n = 21 Con/saline, 20 Con/GR, 18 GFAP-Rs1/saline, and 17 GFAP-Rs1/GR mice. *P < 0.05, **P < 0.01, ***P < 0.001 (Student's t test with Welch's correction). Data are presented as mean ± s.e.m.

Supplementary Figure 8 Effects of constitutive Gs-coupled signaling by astrocytic Rs1.

(a–d) Rs1 expression increases constitutive Gs-coupled signaling in primary astrocytes. Primary astrocyte cultures from wild-type mice were transduced or not (Con) with lentiviral constructs encoding mCherry (mCher) or FLAG-Rs1 (Rs1). None of the cultures were treated with GR-125487. (a) Rs1 expression was confirmed by immunoprecipitation with antibodies to human 5HT4b receptor followed by western blotting with antibodies to FLAG. A cropped western blot is shown from one experiment. (b) Intracellular cAMP levels were measured and normalized to the average level in Con cells. One-way ANOVA: F(2, 19) = 20.02, P < 0.0001. n = 7 Con, 8 mCher, and 7 Rs1 wells per condition from three independent experiments. ***P < 0.001 vs. Con (Dunnett's test). (c) Intracellular calcium levels were measured using Calcium-5, a calcium-sensitive fluorescent dye. Fluorescence intensity was normalized to the average intensity in Con wells. Student's t test: P = 0.02. n = 32 wells per condition from two independent experiments. *p < 0.05. (d) Representative cropped western blots (top) and densitometric quantification (bottom) of phosphorylated (p) and total (t) CREB. tCREB served as a loading control and pCREB/tCREB ratios were normalized to the average ratio in Con cells. Student's t test with Welch's correction: P = 0.0017. n = 6 wells per condition from two independent experiments. **p < 0.01. (e) Untreated GFAP-tTA (Con) and GFAP-Rs1 mice showed no target preference in a probe trial conducted 15 days after training in the Morris water maze. Untreated 5–7-month-old Con and GFAP-Rs1 mice were trained in the Morris water maze as shown in Figure 6a. Three probe trials were conducted before this probe, as shown in Figures 6b–e. Mice were guided to the platform location after completion of each probe trial. One-tailed Student's t test with Welch's correction (Target vs. Other of matching genotype): P = 0.17 (Con), P = 0.47 (GFAP-Rs1). n = 16 Con mice and 16 GFAP-Rs1 mice. (f–g) Untreated 3.5–6-month-old Con and GFAP-Rs1 mice were impaired in a novel object-recognition test. (f) During training, mice were presented for 10 min with one of two sets of identical objects (AA or BB) placed in the right (R) or left (L) half of the arena. One-tailed Student's t test (vs. A/R of matching genotype): P = 0.72 (Con A/L), 0.69 (Con B/R), 0.97 (Con B/L), 0.2 (GFAP-Rs1 A/L), 0.65 (GFAP-Rs1 B/R), and 0.47 (GFAP-Rs1 B/L). n = 12 Con A/R, 12 Con A/L, 5 Con B/R, 5 Con B/L, 8 GFAP-Rs1 A/R, 8 GFAP-Rs1 A/L, 12 GFAP-Rs1 B/R, and 12 GFAP-Rs1 B/L mice. (g) Two days after training, mice were presented for 10 min with a new object and one of the objects they were exposed to during training ('AB'). The average time spent exploring the new object relative to the familiar object is shown. Student's t test: P = 0.0021. n = 26 Con and 24 GFAP-Rs1 mice. **p < 0.01 (Student's t test). (h) Gfap mRNA levels in the cortex of young (2–4 months) and old (19–22 months) GFAP-tTA and GFAP-Rs1 mice. Gapdh served as a loading control. Gfap/Gapdh ratios were normalized to the average ratio in young GFAP-tTA mice. Two-way ANOVA: F(1, 25) = 25.16, p < 0.0001 for age effect. n = 5 Con/young, 10 GFAP-Rs1/young, 5 Con/old, and 9 GFAP-Rs1/old mice. ##p < 0.01 vs. young mice of matching genotype (Bonferroni test). (i–j) Untreated GFAP-Rs1 mice showed normal working memory in the Y maze. Con and GFAP-Rs1 mice were tested in the Y maze at 7–9 (i) and 18–19 (j) months of age. Student's t test (vs. Con): P = 0.76 (i), 0.42 (j). n = 21 Con and 22 GFAP-Rs1 mice (i); 13 Con and 10 GFAP-Rs1 mice (j). Full-length blots are presented in Supplementary Figure 13. Data are presented as mean ± s.e.m.

Supplementary Figure 9 In aging hAPP mice, A2A receptor expression is most prominent in astrocytes adjacent to amyloid plaques, but is not detected in microglia.

Representative photomicrographs of immunostained hippocampal sections are shown. (a) Aβ (6E10 antibody, green) and GFAP/astrocyte (red) staining in a 13-month-old hAPP mouse. Cell nuclei were labeled with DAPI (blue). Scale bar: 50 µm. (b–c) A2A receptor (green) and Iba1/microglia (red) staining in a 13-month-old hAPP mouse. Scale bars: 50 µm (b), 25 µm (c). (d–e) Thioflavin-S staining of amyloid plaques (green) and A2A labeling (red) in the hippocampus of an 18-month-old hAPP mouse. Insets show magnified views of the boxed regions. Scale bars: 50 µm. n = 3 (a), 2 (b–c), 4 (d–e) hAPP mice. DGgl: dentate gyrus granular layer.

Supplementary Figure 10 Astrocytic A2A receptor levels are increased in aging but not young hAPP mice.

(a–b) Representative photomicrographs of hippocampal sections from young (a) and older (b) nontransgenic (NTG) and hAPP mice immunostained for the A2A receptor (green) and GFAP/astrocytes (red). Ages of the mice are indicated in months (m, left). Insets (i–v) show magnified views of the boxed regions. DGgl: dentate gyrus granular layer; DGmol: dentate gyrus molecular layer. n = 4 NTG/3 m, 5 hAPP/3 m, 8 NTG/14 m, 7 hAPP/14 m, and 8 hAPP/18 m mice. Scale bars: 50 µm (a), 100 µm (b).

Supplementary Figure 11 Astrocytic A2A receptor levels are increased in young wild-type mice after kainate administration.

Representative photomicrographs of hippocampal sections from 2–3-month-old wild-type FVBN/J mice immunostained for the A2A receptor (green) and GFAP (red). Mice received a single i.p. injection of saline (Con) or kainate (KA, 30 mg/kg) and were perfused at the indicated time points after injection. Cell nuclei were labeled with DAPI (blue). Insets (i-iv) show magnified views of the boxed regions. DG: dentate gyrus; CA1: cornu ammonis area 1. Scale bar: 200 µm. n = 2 Con, 3 KA-day 1, 3 KA-day 3, and 3 KA-day 7 mice.

Supplementary Figure 12 Conditional ablation of astrocytic A2A receptors does not reduce behavioral abnormalities in young hAPP mice.

(a–d) hAPP mice with or without conditional ablation of astrocytic A2A receptors were assessed in the elevated plus maze at 2–4 months of age (a), the open field at 3–5 months of age (b), and the Morris water maze at 7–9 months of age (c–d). (a) Distance (left) and time spent (right) in the open arms of the elevated plus maze. Con: singly transgenic loxP-Adora2a control mice. One-way ANOVA: F(2, 38) = 4.72, P = 0.015 (left); F(2, 38) = 5.75, P = 0.0066 (right); n = 14 Con, 14 hAPP, and 13 hAPP/A2A-cKO mice. *P < 0.05, **P < 0.01 vs. Con (Dunnett's test). (b) Open-field habituation test. Mice were habituated to the open field in 5-min trials (1–2 trials per day) for 4 days. Graph shows the extent of dishabituation during a test trial 13 days later (test trial relative to the last training trial). One-way ANOVA: F(2, 35) = 7.29, P = 0.0023. n = 14 Con, 12 hAPP, and 12 hAPP/A2A-cKO mice. *P < 0.05, **P < 0.01 vs. Con (Dunnett's test). (c) Distance traveled to reach the platform during hidden platform training in the Morris water maze (two trials per session, two sessions per day for six days). Repeated measures two-way ANOVA revealed a significant difference between Con and hAPP mice (F(1, 20) = 48.36, P < 0.0001), but not between hAPP and hAPP/A2A-cKO mice (F(1, 16) = 0.37, P = 0.55). n = 13 Con, 9 hAPP, and 9 hAPP/A2A-cKO mice. (d) Probe trial conducted one day after training in the Morris water maze. Left, durations in target and non-target (other) quadrants. One-way ANOVA: F(2, 28) = 6.05, P = 0.0065; one-sample t test vs. chance duration of 15 s with FDR correction for multiple comparisons (Target vs. chance): P = 0.0003 (Con), 0.13 (hAPP), 0.15 (hAPP/ A2A-cKO). #P < 0.05, ##P < 0.01 (Dunnett's test); ***P < 0.001 vs. chance duration of 15 s. Right, latency to reach target location. One-way ANOVA: F(2, 29) = 3.78, P = 0.035. oP = 0.066, *P < 0.05 vs. Con (Dunnett's test). n = 13 Con, 10 hAPP, and 8 hAPP/A2A-cKO mice. Data are presented as mean ± s.e.m.

Supplementary Figure 13 Uncropped images of the western blots presented in the figures.

Supplementary information

Supplementary Text and Figures

Supplementary Figures 1–13 and Supplementary Tables 1 and 2 (PDF 3195 kb)

Supplementary Methods Checklist

Statistics Checklist (PDF 152 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Orr, A., Hsiao, E., Wang, M. et al. Astrocytic adenosine receptor A2A and Gs-coupled signaling regulate memory. Nat Neurosci 18, 423–434 (2015). https://doi.org/10.1038/nn.3930

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nn.3930

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing