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:

Young CSF restores oligodendrogenesis and memory in aged mice via Fgf17

An Author Correction to this article was published on 13 December 2022

This article has been updated

Abstract

Recent understanding of how the systemic environment shapes the brain throughout life has led to numerous intervention strategies to slow brain ageing1,2,3. Cerebrospinal fluid (CSF) makes up the immediate environment of brain cells, providing them with nourishing compounds4,5. We discovered that infusing young CSF directly into aged brains improves memory function. Unbiased transcriptome analysis of the hippocampus identified oligodendrocytes to be most responsive to this rejuvenated CSF environment. We further showed that young CSF boosts oligodendrocyte progenitor cell (OPC) proliferation and differentiation in the aged hippocampus and in primary OPC cultures. Using SLAMseq to metabolically label nascent mRNA, we identified serum response factor (SRF), a transcription factor that drives actin cytoskeleton rearrangement, as a mediator of OPC proliferation following exposure to young CSF. With age, SRF expression decreases in hippocampal OPCs, and the pathway is induced by acute injection with young CSF. We screened for potential SRF activators in CSF and found that fibroblast growth factor 17 (Fgf17) infusion is sufficient to induce OPC proliferation and long-term memory consolidation in aged mice while Fgf17 blockade impairs cognition in young mice. These findings demonstrate the rejuvenating power of young CSF and identify Fgf17 as a key target to restore oligodendrocyte function in the ageing brain.

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

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

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

Fig. 1: Young CSF improves memory consolidation and promotes OPC proliferation and differentiation.
Fig. 2: SRF is induced by young CSF and mediates CSF-induced OPC proliferation.
Fig. 3: SRF signalling is downregulated in hippocampal OPCs with ageing and induced by acute injection of young CSF.
Fig. 4: Fgf17 induces OPC proliferation and improves memory.

Similar content being viewed by others

Data availability

All data are available in the main text or the Supplementary Information. Raw and processed sequencing data were deposited to NCBI’s Sequence Read Archive and Gene Expression Omnibus databases using accession code GSE198008.

Code availability

All analyses were carried out using freely available software packages. Custom code used to analyse the RNA-seq data and datasets generated and/or processed in the current study is available from the corresponding authors on request.

Change history

References

  1. Pluvinage, J. V. & Wyss-Coray, T. Systemic factors as mediators of brain homeostasis, ageing and neurodegeneration. Nat. Rev. Neurosci. 21, 93–102 (2020).

    Article  CAS  Google Scholar 

  2. Castellano, J. M. et al. Human umbilical cord plasma proteins revitalize hippocampal function in aged mice. Nature 544, 488–492 (2017).

    Article  ADS  CAS  Google Scholar 

  3. Villeda, S. A. et al. Young blood reverses age-related impairments in cognitive function and synaptic plasticity in mice. Nat. Med. 20, 659–663 (2014).

    Article  CAS  Google Scholar 

  4. Lehtinen, M. K. et al. The cerebrospinal fluid provides a proliferative niche for neural progenitor cells. Neuron 69, 893–905 (2011).

    Article  CAS  Google Scholar 

  5. Silva-Vargas, V., Maldonado-Soto, A. R., Mizrak, D., Codega, P. & Doetsch, F. Age-dependent niche signals from the choroid plexus regulate adult neural stem cells. Cell Stem Cell 19, 643–652 (2016).

    Article  CAS  Google Scholar 

  6. Fame, R. M. & Lehtinen, M. K. Emergence and developmental roles of the cerebrospinal fluid system. Dev. Cell 52, 261–275 (2020).

    Article  CAS  Google Scholar 

  7. Chen, C. P., Chen, R. L. & Preston, J. E. The influence of ageing in the cerebrospinal fluid concentrations of proteins that are derived from the choroid plexus, brain, and plasma. Exp. Gerontol. 47, 323–328 (2012).

    Article  CAS  Google Scholar 

  8. Baird, G. S. et al. Age-dependent changes in the cerebrospinal fluid proteome by slow off-rate modified aptamer array. Am. J. Pathol. 180, 446–456 (2012).

    Article  CAS  Google Scholar 

  9. Li, G. et al. Cerebrospinal fluid concentration of brain-derived neurotrophic factor and cognitive function in non-demented subjects. PLoS ONE 4, e5424 (2009).

    Article  ADS  Google Scholar 

  10. Pan, S., Mayoral, S. R., Choi, H. S., Chan, J. R. & Kheirbek, M. A. Preservation of a remote fear memory requires new myelin formation. Nat. Neurosci. 23, 487–499 (2020).

    Article  CAS  Google Scholar 

  11. Vetere, G. et al. Chemogenetic interrogation of a brain-wide fear memory network in mice. Neuron 94, 363–374 (2017).

    Article  CAS  Google Scholar 

  12. Fogel, S. M. et al. fMRI and sleep correlates of the age-related impairment in motor memory consolidation. Hum. Brain Mapp. 35, 3625–3645 (2014).

    Article  Google Scholar 

  13. Gibson, E. M. et al. Neuronal activity promotes oligodendrogenesis and adaptive myelination in the mammalian brain. Science 344, 1252304 (2014).

    Article  Google Scholar 

  14. Dugas, J. C. & Emery, B. Purification of oligodendrocyte precursor cells from rat cortices by immunopanning. Cold Spring Harb. Protoc. 2013, 745–758 (2013).

    Article  Google Scholar 

  15. Sun, L. O. et al. Spatiotemporal control of CNS myelination by oligodendrocyte programmed cell death through the TFEB–PUMA axis. Cell 175, 1811–1826 (2018).

    Article  CAS  Google Scholar 

  16. Zuchero, J. B. et al. CNS myelin wrapping is driven by actin disassembly. Dev. Cell 34, 152–167 (2015).

    Article  CAS  Google Scholar 

  17. Schwarz, N. et al. Human cerebrospinal fluid promotes long-term neuronal viability and network function in human neocortical organotypic brain slice cultures. Sci. Rep. 7, 12249 (2017).

    Article  ADS  Google Scholar 

  18. Wentling, M. et al. A metabolic perspective on CSF-mediated neurodegeneration in multiple sclerosis. Brain 142, 2756–2774 (2019).

    Article  Google Scholar 

  19. Mathur, D. et al. Bioenergetic failure in rat oligodendrocyte progenitor cells treated with cerebrospinal fluid derived from multiple sclerosis patients. Front. Cell. Neurosci. 11, 209 (2017).

    Article  Google Scholar 

  20. Braun, T. & Gautel, M. Transcriptional mechanisms regulating skeletal muscle differentiation, growth and homeostasis. Nat. Rev. Mol. Cell Biol. 12, 349–361 (2011).

    Article  CAS  Google Scholar 

  21. Guo, Y. et al. Hierarchical and stage-specific regulation of murine cardiomyocyte maturation by serum response factor. Nat. Commun. 9, 3837 (2018).

    Article  ADS  Google Scholar 

  22. Knoll, B. & Nordheim, A. Functional versatility of transcription factors in the nervous system: the SRF paradigm. Trends Neurosci. 32, 432–442 (2009).

    Article  Google Scholar 

  23. Miralles, F., Posern, G., Zaromytidou, A. I. & Treisman, R. Actin dynamics control SRF activity by regulation of its coactivator MAL. Cell 113, 329–342 (2003).

    Article  CAS  Google Scholar 

  24. Knoll, B. et al. Serum response factor controls neuronal circuit assembly in the hippocampus. Nat. Neurosci. 9, 195–204 (2006).

    Article  Google Scholar 

  25. Lahoute, C. et al. Premature aging in skeletal muscle lacking serum response factor. PLoS ONE 3, e3910 (2008).

    Article  ADS  Google Scholar 

  26. Mergoud Dit Lamarche, A. et al. UNC-120/SRF independently controls muscle aging and lifespan in Caenorhabditis elegans. Aging Cell 17, e12713 (2018).

    Article  Google Scholar 

  27. Ximerakis, M. et al. Single-cell transcriptomic profiling of the aging mouse brain. Nat. Neurosci. 22, 1696–1708 (2019).

    Article  CAS  Google Scholar 

  28. Falcao, A. M. et al. Disease-specific oligodendrocyte lineage cells arise in multiple sclerosis. Nat. Med. 24, 1837–1844 (2018).

    Article  CAS  Google Scholar 

  29. Iacono, G., Altafini, C. & Torre, V. Early phase of plasticity-related gene regulation and SRF dependent transcription in the hippocampus. PLoS ONE 8, e68078 (2013).

    Article  ADS  CAS  Google Scholar 

  30. Kuzniewska, B. et al. Brain-derived neurotrophic factor induces matrix metalloproteinase 9 expression in neurons via the serum response factor/c-Fos pathway. Mol. Cell. Biol. 33, 2149–2162 (2013).

    Article  CAS  Google Scholar 

  31. Sasayama, D. et al. Genome-wide quantitative trait loci mapping of the human cerebrospinal fluid proteome. Hum. Mol. Genet. 26, 44–51 (2017).

    CAS  Google Scholar 

  32. Sathyan, S. et al. Plasma proteomic profile of age, health span, and all-cause mortality in older adults. Aging Cell 19, e13250 (2020).

    Article  CAS  Google Scholar 

  33. Esnault, C. et al. Rho–actin signaling to the MRTF coactivators dominates the immediate transcriptional response to serum in fibroblasts. Genes Dev. 28, 943–958 (2014).

    Article  CAS  Google Scholar 

  34. Fortin, D., Rom, E., Sun, H., Yayon, A. & Bansal, R. Distinct fibroblast growth factor (FGF)/FGF receptor signaling pairs initiate diverse cellular responses in the oligodendrocyte lineage. J. Neurosci. 25, 7470–7479 (2005).

    Article  CAS  Google Scholar 

  35. Ramanan, N. et al. SRF mediates activity-induced gene expression and synaptic plasticity but not neuronal viability. Nat. Neurosci. 8, 759–767 (2005).

    Article  CAS  Google Scholar 

  36. Etkin, A. et al. A role in learning for SRF: deletion in the adult forebrain disrupts LTD and the formation of an immediate memory of a novel context. Neuron 50, 127–143 (2006).

    Article  CAS  Google Scholar 

  37. Pan, S., Mayoral, S. R., Choi, H. S., Chan, J. R. & Kheirbek, M. A. Preservation of a remote fear memory requires new myelin formation. Nat. Neurosci. 23, 487–499 (2020).

    Article  CAS  Google Scholar 

  38. Xiao, L. et al. Rapid production of new oligodendrocytes is required in the earliest stages of motor-skill learning. Nat. Neurosci. 19, 1210–1217 (2016).

    Article  CAS  Google Scholar 

  39. Steadman, P. E. et al. Disruption of oligodendrogenesis impairs memory consolidation in adult mice. Neuron 105, 150–164 (2020).

    Article  CAS  Google Scholar 

  40. Wang, F. et al. Myelin degeneration and diminished myelin renewal contribute to age-related deficits in memory. Nat. Neurosci. 23, 481–486 (2020).

    Article  Google Scholar 

  41. Chen, J. F. et al. Enhancing myelin renewal reverses cognitive dysfunction in a murine model of Alzheimer’s disease. Neuron 109, 2292–2307 (2021).

    Article  CAS  Google Scholar 

  42. Segel, M. et al. Niche stiffness underlies the ageing of central nervous system progenitor cells. Nature 573, 130–134 (2019).

    Article  ADS  CAS  Google Scholar 

  43. Neumann, B. et al. Metformin restores CNS remyelination capacity by rejuvenating aged stem cells. Cell Stem Cell 25, 473–485 (2019).

    Article  CAS  Google Scholar 

  44. Bonetto, G., Belin, D. & Karadottir, R. T. Myelin: a gatekeeper of activity-dependent circuit plasticity? Science 374, eaba6905 (2021).

    Article  Google Scholar 

  45. Xu, J., Liu, Z. & Ornitz, D. M. Temporal and spatial gradients of Fgf8 and Fgf17 regulate proliferation and differentiation of midline cerebellar structures. Development 127, 1833–1843 (2000).

    Article  CAS  Google Scholar 

  46. Furusho, M., Ishii, A., Hebert, J. M. & Bansal, R. Developmental stage-specific role of Frs adapters as mediators of FGF receptor signaling in the oligodendrocyte lineage cells. Glia 68, 617–630 (2020).

    Article  Google Scholar 

  47. Oh, L. Y. et al. Fibroblast growth factor receptor 3 signaling regulates the onset of oligodendrocyte terminal differentiation. J. Neurosci. 23, 883–894 (2003).

    Article  CAS  Google Scholar 

  48. Kang, W., Nguyen, K. C. Q. & Hebert, J. M. Transient redirection of SVZ stem cells to oligodendrogenesis by FGFR3 activation promotes remyelination. Stem Cell Rep. 12, 1223–1231 (2019).

    Article  CAS  Google Scholar 

  49. Jen, Y. H., Musacchio, M. & Lander, A. D. Glypican-1 controls brain size through regulation of fibroblast growth factor signaling in early neurogenesis. Neural Dev. 4, 33 (2009).

    Article  Google Scholar 

  50. Scearce-Levie, K. et al. Abnormal social behaviors in mice lacking Fgf17. Genes Brain Behav. 7, 344–354 (2008).

    Article  CAS  Google Scholar 

  51. De Miguel, Z. et al. Exercise plasma boosts memory and dampens brain inflammation via clusterin. Nature 600, 494–499 (2021).

    Article  ADS  Google Scholar 

  52. Liu, L. & Duff, K. A technique for serial collection of cerebrospinal fluid from the cisterna magna in mouse. J. Vis. Exp. https://doi.org/10.3791/960 (2008).

  53. Smith, A., Wu, A. H., Lynch, K. L., Ko, N. & Grenache, D. G. Multi-wavelength spectrophotometric analysis for detection of xanthochromia in cerebrospinal fluid and accuracy for the diagnosis of subarachnoid hemorrhage. Clin. Chim. Acta 424, 231–236 (2013).

    Article  CAS  Google Scholar 

  54. Olsson, M., Arlig, J., Hedner, J., Blennow, K. & Zetterberg, H. Sleep deprivation and cerebrospinal fluid biomarkers for Alzheimer’s disease. Sleep https://doi.org/10.1093/sleep/zsy025 (2018).

  55. Olsson, M., Arlig, J., Hedner, J., Blennow, K. & Zetterberg, H. Sleep deprivation and plasma biomarkers for Alzheimer’s disease. Sleep Med. 57, 92–93 (2019).

    Article  Google Scholar 

  56. Lynch, H. J., Rivest, R. W. & Wurtman, R. J. Artificial induction of melatonin rhythms by programmed microinfusion. Neuroendocrinology 31, 106–111 (1980).

    Article  CAS  Google Scholar 

  57. Pluvinage, J. V. et al. CD22 blockade restores homeostatic microglial phagocytosis in ageing brains. Nature 568, 187–192 (2019).

    Article  ADS  CAS  Google Scholar 

  58. Lukinavicius, G. et al. Fluorogenic probes for live-cell imaging of the cytoskeleton. Nat. Methods 11, 731–733 (2014).

    Article  CAS  Google Scholar 

  59. Friedman, P. L. & Ellisman, M. H. Enhanced visualization of peripheral nerve and sensory receptors in the scanning electron microscope using cryofracture and osmium–thiocarbohydrazide–osmium impregnation. J. Neurocytol. 10, 111–131 (1981).

    Article  CAS  Google Scholar 

  60. Willingham, M. C. & Rutherford, A. V. The use of osmium–thiocarbohydrazide–osmium (OTO) and ferrocyanide-reduced osmium methods to enhance membrane contrast and preservation in cultured cells. J. Histochem. Cytochem. 32, 455–460 (1984).

    Article  CAS  Google Scholar 

  61. Ewald, A. J. et al. Mammary collective cell migration involves transient loss of epithelial features and individual cell migration within the epithelium. J. Cell Sci. 125, 2638–2654 (2012).

    CAS  Google Scholar 

  62. McDonald, K. L. & Webb, R. I. Freeze substitution in 3 hours or less. J. Microsc. 243, 227–233 (2011).

    Article  CAS  Google Scholar 

  63. Emery, B. & Dugas, J. C. Purification of oligodendrocyte lineage cells from mouse cortices by immunopanning. Cold Spring Harb. Protoc. 2013, 854–868 (2013).

    Article  Google Scholar 

  64. Muhar, M. et al. SLAM-seq defines direct gene-regulatory functions of the BRD4–MYC axis. Science 360, 800–805 (2018).

    Article  CAS  Google Scholar 

  65. Stockel, D. et al. Multi-omics enrichment analysis using the GeneTrail2 web service. Bioinformatics 32, 1502–1508 (2016).

    Article  Google Scholar 

  66. Hahn, O. et al. CoolMPS for robust sequencing of single-nuclear RNAs captured by droplet-based method. Nucleic Acids Res. 49, e11 (2021).

    Article  CAS  Google Scholar 

  67. Newman, A. M. et al. Determining cell type abundance and expression from bulk tissues with digital cytometry. Nat. Biotechnol. 37, 773–782 (2019).

    Article  CAS  Google Scholar 

  68. Steen, C. B., Liu, C. L., Alizadeh, A. A. & Newman, A. M. Profiling cell type abundance and expression in bulk tissues with CIBERSORTx. Methods Mol. Biol. 2117, 135–157 (2020).

    Article  CAS  Google Scholar 

  69. Wolf, F. A., Angerer, P. & Theis, F. J. SCANPY: large-scale single-cell gene expression data analysis. Genome Biol. 19, 15 (2018).

    Article  Google Scholar 

  70. Schaum, N. et al. Ageing hallmarks exhibit organ-specific temporal signatures. Nature 583, 596–602 (2020).

    Article  ADS  CAS  Google Scholar 

  71. Spitzer, S. O. et al. Oligodendrocyte progenitor cells become regionally diverse and heterogeneous with age. Neuron 101, 459–471 (2019).

    Article  CAS  Google Scholar 

  72. Mathys, H. et al. Single-cell transcriptomic analysis of Alzheimer’s disease. Nature 570, 332–337 (2019).

    Article  ADS  CAS  Google Scholar 

  73. Zhou, Y. et al. Human and mouse single-nucleus transcriptomics reveal TREM2-dependent and TREM2-independent cellular responses in Alzheimer’s disease. Nat. Med. 26, 131–142 (2020).

    Article  CAS  Google Scholar 

  74. The Tabula Muris Consortium. A single-cell transcriptomic atlas characterizes ageing tissues in the mouse. Nature 583, 590–595 (2020).

  75. Matys, V. et al. TRANSFAC and its module TRANSCompel: transcriptional gene regulation in eukaryotes. Nucleic Acids Res. 34, D108–D110 (2006).

    Article  ADS  CAS  Google Scholar 

  76. Gerstner, N. et al. GeneTrail 3: advanced high-throughput enrichment analysis. Nucleic Acids Res. 48, W515–W520 (2020).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank the members of the Wyss-Coray and Zuchero laboratories for feedback and support. Specifically, we thank H. Kantarci for advice on TEM tissue processing, imaging and analysis, H. Zhang and K. Dickey for laboratory management, and B. Carter for flow cytometry technical expertise. We thank V. Galata for graphical abstract design. We thank E. Mignot and J. Dalmau for providing human CSF samples. We also thank D. Jorgens and the staff at the University of California–Berkeley Electron Microscope Laboratory for EM sample preparation and data collection. This work was funded by the Department of Veterans Affairs (T.W.-C.), the National Institute on Aging (RF1-AG064897-02 to T.W.-C., T32AG000266 to M.S.H.), the NOMIS Foundation (T.W.-C.), the Nan Fung Life Sciences Aging Research Fund (T.W.-C.), the Glenn Foundation for Aging Research (T.W.-C.), the Big Idea Brain Rejuvenation Project and Interdisciplinary Scholar fellowship from the Wu Tsai Neurosciences Institute (T.W.-C. and T.I.), the Zuckerman STEM leadership fellowship and Tel Aviv University President Award for women postdoctoral scholars (T.I.), the National MS Society Harry Weaver Neuroscience Scholar Award (J.B.Z.), the McKnight Scholar Award (J.B.Z.), the Myra Reinhard Family Foundation and the National Institutes of Health (R01-NS119823 to J.B.Z.). H.Z. is a Wallenberg Scholar supported by grants from the Swedish Research Council (2018-02532), the European Research Council (681712), Swedish State Support for Clinical Research (ALFGBG-720931), the Alzheimer Drug Discovery Foundation (ADDF), USA (201809-2016862) and the UK Dementia Research Institute at UCL.

Author information

Authors and Affiliations

Authors

Contributions

T.I. and T.W.-C. conceptualized the study. T.I. performed all surgical procedures. A. Kaur, S.M., H.S. and T.I. performed and analysed histology and cell culture experiments. A. Kaur, L.Y., J.L. and T.I. designed and performed behaviour experiments. S.M. performed SLAMseq experiments, which were designed and analysed by F.K. and T.I. A.R.M. and T.I. performed nuclei sorting and RNA-seq experiments with guidance from N.L. and O.H. F.K. and T.I. analysed the datasets. M.A.G. isolated OPCs from mice with loxP-flanked Srf, and M.I. and M.S.H. assisted with cell culture experiments. A.C.Y., A.R.M. and T.I. preformed labelled CSF and Fgf17 experiments. S.R.S. assisted with CSF collection. R.P. and B.L. assisted with bioinformatic analysis. H.Z. provided human CSF samples. T.I. wrote the manuscript with input from all authors, T.I. and F.K. designed manuscript figures, and J.B.Z. and T.W.-C. edited the manuscript. A. Keller, J.B.Z. and T.W.-C. supervised the work.

Corresponding authors

Correspondence to Tal Iram or Tony Wyss-Coray.

Ethics declarations

Competing interests

T.W.-C. and T.I. are co-inventors on a patent application related to the work published in this paper (STDU2-39617.101, S21-153-Methods and compositions for improved memory in the aging). H.Z. has served at scientific advisory boards and/or as a consultant for Abbvie, Alector, Annexon, Artery Therapeutics, AZTherapies, CogRx, Denali, Eisai, Nervgen, Novo Nordisk, Passage Bio, Pinteon Therapeutics, Red Abbey Labs, Roche, Samumed, Siemens Healthineers, Triplet Therapeutics and Wave, has given lectures in symposia sponsored by Cellectricon, Fujirebio, Alzecure, Biogen and Roche, and is a cofounder of Brain Biomarker Solutions in Gothenburg AB (BBS), which is a part of the GU Ventures Incubator Program (outside the scope of the submitted work).

Peer review

Peer review information

Nature thanks Klaus-Armin Nave and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data figures and tables

Extended Data Fig. 1 Bulk RNAseq, infusion site details and overall overview of proliferating cells.

a, Relative proportions of cell types as predicted by deconvolution analysis of bulk RNAseq of aged mice infused with aCSF or YM-CSF (aCSF n = 8, YM-CSF n = 7). b, Predicted number of DEGs per cell type by deconvolution analysis of bulk RNAseq of aged mice infused with aCSF or YM-CSF (aCSF n = 8, YM-CSF n = 7). c, Effect size of the subset of oligodendrocyte genes in Fig. 1d 16 h following acute injection of YM-CSF or aged mouse CSF (AM-CSF) calculated over aCSF as control (n = 4; Wilcoxon rank sum test). d, Location of infusion site. Image source: Allen Institute, Mouse brain atlas (coronal). e, Location of analysis site. Image source: Allen Institute, Mouse brain atlas (coronal). f, Hippocampal slice of 10-month-old mice given an EdU pulse prior to surgery showing low baseline proliferation, and three pulses of BrdU at day 5 and 6 of infusion showing an overall increase in proliferating cells following YM-CSF infusion (n = 4 per group; repeated measures two-way ANOVA followed by Sidak’s post-hoc test; Means ± SEM). g, Representative images of EdU (red) and BrdU (green) cells in mice with no surgery or infused with aCSF or YM-CSF. Scale bar, 500 μm. h, RNAscope of Pdgfrα+EdU+ cells in hippocampus of 2-month-old (young) and 19-month-old (aged) mice (n = 3; two-sided t-test; mean ± s.e.m.). i, Representative images of analysis in panel h. Arrows pointing to Pdgfrα+EdU+ cells. Scale bar, 100 μm.

Source Data

Extended Data Fig. 2 Cortical Pdgfrα+EdU+ cells and identity of Pdgfrα EDU+ cells.

a, Hippocampal density of Pdgfrα+ EdU+ cells per mm2 (aCSF n = 7, YM-CSF n = 8; two-sided t-test; mean ± s.e.m.). b, Hippocampal density of Pdgfrα+ cells per mm2 (aCSF n = 7, YM-CSF n = 8; two-sided t-test; mean ± s.e.m.). c, Location of region of interest in the cortex. Scale bar, 100 μm. d, Percentage of Pdgfrα+ EdU+ / Pdgfrα+ cells showing very low proliferation rates of OPCs in the cortex (n = 6; two-sided t-test; mean ± s.e.m.). e, Cortical density of Pdgfrα+ EdU+ cells per mm2 (n = 6; two-sided t-test; mean ± s.e.m.). f, Cortical density of Pdgfrα+ cells per mm2 (n = 6; two-sided t-test; mean ± s.e.m.). g, Percentage of Pdgfrα+ EdU+ / EdU+ in the hippocampus of aged mice infused with YM-CSF (n = 3). h, Example of IBA+ EdU+ cells in the hippocampus (n = 3). Scale bar, 50 μm. Insert, 10 μm. i, Example of GFAP+ EdU+ cells in the hippocampus (n = 3). Scale bar, 50 μm. Insert, 10 μm.

Source Data

Extended Data Fig. 3 Young CSF increases number of myelinated axons in the molecular layer.

a, Representative overview of 1mm diameter biopsy punch in the hippocampus. b, Representative overview of molecular layer (MoL, between dashed lines) before and after TEM imaging of three 10x10 montage squares (n=7). c, Representative montage of MoL of aged mouse infused with aCSF and YM-CSF (n = 7). Scale bar, 10 μm. d, Representative higher resolution image of aged mouse infused with aCSF and YM-CSF (n = 7). Scale bar, 1 μm. e, g-ratio analysis of myelinated axons in molecular layer. (n = 3 mice per group, aCSF n = 321 axons, YM-CSF n = 291 axons).

Source Data

Extended Data Fig. 4 Young CSF boosts OPC differentiation in vitro and validation of OPC culture purity.

a, Related to images in Fig 1o. Overview of MBP stain of OLs at day 4 of differentiation supplemented with 10% aCSF or YH-CSF (aCSF n = 3 coverslips, YH-CSF n = 2 coverslips). b, Quantification of MBP intensity of day 4 differentiated OLs. Scale bar, 200 μm. (aCSF n = 3 coverslips, YH-CSF n = 2 coverslips; two-sided t-test; mean ± s.e.m). c, Primary rat OPC cultures were supplemented with 10% aCSF or YH-CSF for 6 h and stained for NG2 (green), Olig2 (grey) and Acta2 (red). (n = 3 coverslips; Scale bar, 100 μm). d, Higher magnification of primary rat OPC cultures were supplemented with 10% aCSF or YH-CSF for 6 h and stained for NG2 (green), Olig2 (grey) and Acta2 (red). (n = 3 coverslips; Scale bar, 20 μm).

Source Data

Extended Data Fig. 5 SLAMseq QC and principal component analysis.

a, Overall conversion rates in all SLAMseq samples, showing an enrichment for T>C mutation rate (orange bar) which increases with longer incubation time (6 h). b–c, Distribution of T>C mutations across b, read position and c, 3’UTR position indicating an equal distribution of s4U incorporation along the positive strand. d–e, UMAP of aCSF and YH-CSF samples in both time points by all genes detected in the d, total and e, nascent mRNA counts. (young CSF 1 h n = 4, all the rest n = 5). f, Gene set enrichment analysis (GSEA) of 6hr genes sorted by log2FC showing an enrichment for SRF target genes by TRANSFAC75. g, Overall log2FC enrichment indicating upregulation of SRF target genes (TRANSFAC and curated list) and actin cytoskeleton genes in YH-CSF treated OPCs over aCSF. (SRF TRANSFAC (423 genes), validated SRF targets from literature (74 genes) and actin genes (212 genes); Wilcoxon rank sum test; box show the median and the 25–75th percentiles, and the whiskers indicate values up to 1.5-times the interquartile range).

Extended Data Fig. 6 YH-CSF induces actin cytoskeleton alterations in vitro.

a–b, Actin filament content measured by live imaging using SiR-actin (red) throughout 4hr of aCSF and YH-CSF exposure. Average SiR-actin a, intensity and b, area in rat OPC cultures exposed to aCSF or YH-CSF (n = 6 wells per condition; Means ± SEM). c, Representative images of experiment quantified in panel a and b. Scale bar 200 μm. d, OPC coverslips were treated with YH-CSF for 6 h and stained for phalloidin. Histogram of the percentage of OPC with the indicated number of growth cones per cell. YH-CSF treated cells show a shift towards more growth cones per cell (n = 3 coverslips per condition, total of 200 cells analyzed per condition; two-way ANOVA followed by Sidak’s post-hoc test; Means ± SEM). Scale bar 20 μm. e, mouse OPC primary cultures from SRF-fl/fl pups infected with CRE-GFP and CRE-GFP AAVs to induce recombination. Representative images of infected cells (green) 48 h after infection. Scale bar, 100 μm. f, Normalized SRF mRNA levels as measured by RT-PCR (n = 3 coverslips per condition; mean ± s.e.m.). g, Representative image of data presented in figure 2h. Scale bar, 20 μm. h, Quantification of GFP+ cells per image in SRF-WT and SRF-KO cells treated with 10% aCSF or YH-CSF. (n = 3; mean ± s.e.m.). i, Quantification of number of DAPI cells per image in SRF-WT and SRF-KO cells treated with 10% aCSF or YH-CSF. (n = 3; mean ± s.e.m.). Data in panels a-i were replicated in two independent experiments.

Source Data

Extended Data Fig. 7 Bulk RNAseq of hippocampal OPC and OL nuclei from young and aged mice.

a, Gating strategy for sorting of hippocampal OPC and OL nuclei. b, Heatmap of expression OPC and OL specific genes across young and aged OPC and OL samples (aged OL n = 3, rest n = 4). c, Volcano plot showing OL genes up and downregulated with age (n = 4; p. adjusted value by Wald test in DESeq2). d, Pathways enriched (red) or depleted (blue) in hippocampal OLs with age (unweighted Kolmogorov-Smirnow test).

Extended Data Fig. 8 Bulk RNAseq of hippocampal OPC and OL nuclei from aged mice following acute injection and Srf levels in neurons.

a, Box plot of effect size of Srf targets (TRANSFAC database) in hippocampal OLs from aged vs. young, YM-CSF vs. aCSF at 1 h and 6 h timepoints (n = 4; genes pre-filtered by p < 0.05 cutoff; Wilcoxon rank sum test, box show the median and the 25–75th percentiles, and the whiskers indicate values up to 1.5-times the interquartile range). b, Pathways enriched (red) or depleted (blue) in hippocampal OPCs 1hr following injection of aCSF or YM-CSF (n = 4; p. adjusted value by Wald test in DESeq2). c, Volcano plot showing OPC genes up and down regulated 1hr following CSF injection (n = 4; p. adjusted value by Wald test in DESeq2). d, Volcano plot showing OPC genes up and down regulated 6hr following CSF injection (n = 4; p. adjusted value by Wald test in DESeq2). e, Neuronal Srf intensity in CA1 in young and aged mice. (n = 3; two-sided t-test; mean ± s.e.m). f, Representative image of panel e. Scale bar, 70 μm. g, Neuronal Srf intensity in CA1 in aged mice following YM-CSF infusion. (n = 4; two-sided t-test; mean ± s.e.m). h, Representative image of panel g. Scale bar, 70 μm.

Source Data

Extended Data Fig. 9 Fgf8 induces OPC proliferation and Fgf17 induces SRF reporter activation mediated by actin dynamics and Fgfr3.

a, Dose-dependent activation of SRE-GFP reporter by increasing concentrations of Fgf8 and representative images of the experiment at 15.5 h. Scale bar, 400 μm. (n = 3; similar control as in Fig. 4c; one-way ANOVA followed by Sidak’s post-hoc test; mean ± s.e.m.). b, Percentage of BRDU+/DAPI primary rat OPCs treated with 10, 20, 40 ng/ml Fgf8. (n = 4; one-way ANOVA followed by Tukey’s post-hoc test; mean ± s.e.m.). c, Quantification of OPC proliferating cells (Pdgfrα+EDU+ / Pdgfrα+ cells) in the CA1 region of the hippocampus of 20-month-old mice following a week of aCSF or Fgf8 infusion. (aCSF n = 8 similar control as in Fig. 4l, Fgf8 n = 4; two-sided t-test; mean ± s.e.m.). d, SRE-GFP activation with 200 ng/ml Fgf17 following 30 min pre-treatment with Jasplakinolide (Jasp, 125 or 250 nM) or Latrunculin A (LatA, 250 or 500 nM). (n = 3; Two-way ANOVA with Tukey’s multiple comparisons test; mean ± s.e.m.). e, SRE-GFP activation with 200 ng/ml Fgf17 following 30 min pre-treatment with blocking antibodies for FgfR1, FgfR2, FgfR3 (all 50 μg/ml) or FgfR3 alone (n = 3; One-way ANOVA with Sidak’s multiple comparisons test; mean ± s.e.m.). f, Example of Pdgfrα+ Fgfr3+ cells in the hippocampus of young mice. (n = 3). Scale bar, 5 μm.

Source Data

Extended Data Fig. 10 Fgf17 is predominantly expressed in the brain by a subset of neurons and is downregulated with age.

a, Fgf17 is predominantly expressed in the brain based on the human protein atlas. b, Fgf17 is expressed by cortical glutamatergic neurons in the young adult mouse (Allen brain atlas). c, Sub-clustering of mouse cortical layer 4/5 neurons indicates expression by a subset of cortical neurons (Allen brain atlas). d, Gene set enrichment analysis of genes mostly correlated with Fgf17 in layer 4/5 neurons (Allen brain atlas). e, Fgf17 is expressed by cortical glutamatergic and GABAergic neurons in the human cortex (Allen brain atlas). f, Representative image of analysis in panel g. Scale bar, 100 μm. g, Fgf17 mRNA expression in cortical neurons drops dramatically in aged mice. (n = 3; two-way student t-test; mean ± s.e.m.). h, Fgf17 protein expression in cortical and hippocampal neurons drops dramatically in aged mice. (n = 3; mean ± s.e.m.). i, Representative images of analysis in panel h and Fig. 4f. Scale bar, 20 μm.

Source Data

Extended Data Fig. 11 Perfusion of labeled YH-CSF and mouse Fgf17 to the brain parenchyma and working model.

a, Deposition of labeled Fgf17 on ventricular walls 3 h post ICV acute injection (n = 3). Scale bar, 300 μm. b, Deposition of labeled YH-CSF on lateral ventricle walls 2 h post ICV acute injection (n = 3). Scale bar, 100 μm. c, Labeled Fgf17 in perivascular spaces in the molecular layer of the hippocampus (n = 3). Scale bar, 50 μm. d, Labeled YH-CSF in perivascular spaces in the molecular layer of the hippocampus (n = 3). Scale bar, 20 μm. e, YH-CSF in the perivascular space in between the vessel (green) and astrocyte endfeet (white; n = 3). Scale bar, 20 μm. f, Orthogonal slice of YH-CSF (magenta) in perivascular space, in between the vessel (green) and astrocyte endfeet (white; n = 3). Scale bar, 20 μm. g, Working model. OPC proliferation and differentiation (termed oligodendrogenesis) slow down with age40,41,42,43. Re-exposure of the aged brain to young CSF or the brain-specific growth factor Fgf1745, boost hippocampal oligodendorgenesis, concomitant with improvement in long term memory recall.

Supplementary information

Reporting Summary

Peer Review File

Supplementary Table 1

Normalized gene counts and summary statistics of bulk RNA-seq of aged hippocampi infused with aCSF or YM-CSF for 6 d (linked to Fig. 1).

Supplementary Table 2

Normalized gene counts and summary statistics of hippocampal OPC nuclei 16 h after acute ICV injection with aCSF, YM-CSF or AM-CSF (linked to Extended Data Fig. 1c).

Supplementary Table 3

SLAMseq gene counts and statistics: nascent (TC) and total mRNA counts for rat OPCs treated with aCSF or YM-CSF for 1 or 6 h (linked to Fig. 2).

Supplementary Table 4

Gene lists used in the study. a, b, SRF targets according to the human TRANSFAC database (aligned to rat and mouse). c, Curated list of SRF targets from the literature. d, GO term actin cytoskeleton (rat).

Supplementary Table 5

Normalized gene counts and summary statistics for sorted OPC and OL nuclei from young and aged hippocampi (linked to Fig. 3).

Supplementary Table 6

Normalized gene counts and summary statistics for aged hippocampal OPC and OL nuclei 1 or 6 h after acute ICV injection with aCSF or YM-CSF (linked to Fig. 3).

Supplementary Table 7

SRF targets present in CSF proteomic datasets. a, Proteins tested in the SRE reporter assay. b, SRF targets in CSF datasets that were not tested in the SRE reporter assay.

Supplementary Video 1

OPCs growing under differentiation conditions with 10% aCSF. OPCs were treated with 10% aCSF under differentiation conditions (with T3) for 4 d and imaged in the IncuCyte every 2 h for 4 d. Scale bar, 200 μm.

Supplementary Video 2

OPCs growing under differentiation conditions with 10% YM-CSF. OPCs were treated with 10% YH-CSF under differentiation conditions (with T3) for 4 d and imaged in the IncuCyte every 2 h for 4 d. Scale bar, 200 μm.

Source data

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Iram, T., Kern, F., Kaur, A. et al. Young CSF restores oligodendrogenesis and memory in aged mice via Fgf17. Nature 605, 509–515 (2022). https://doi.org/10.1038/s41586-022-04722-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41586-022-04722-0

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

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