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Le AD, Fu M, Kumar R, Zacharias G, Garcia ADR. Astrocyte modulation of synaptic plasticity mediated by activity-dependent Sonic hedgehog signaling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.05.588352. [PMID: 38915525 PMCID: PMC11195099 DOI: 10.1101/2024.04.05.588352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
The influence of neural activity on astrocytes and their reciprocal interactions with neurons has emerged as an important modulator of synapse function. Astrocytes exhibit activity-dependent changes in gene expression, yet the molecular mechanisms by which they accomplish this have remained largely unknown. The molecular signaling pathway, Sonic hedgehog (Shh), mediates neuron-astrocyte communication and regulates the organization of cortical synapses. Here, we demonstrate that neural activity stimulates Shh signaling in cortical astrocytes and upregulates expression of Hevin and SPARC, astrocyte derived molecules that modify synapses. Whisker stimulation and chemogenetic activation both increase Shh activity in deep layers of the somatosensory cortex, where neuron-astrocyte Shh signaling is predominantly found. Experience-dependent Hevin and SPARC require intact Shh signaling and selective loss of pathway activity in astrocytes occludes experience-dependent structural plasticity. Taken together, these data identify Shh signaling as an activity-dependent, neuronal derived cue that stimulates astrocyte interactions with synapses and promotes synaptic plasticity.
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Affiliation(s)
- Anh Duc Le
- Department of Biology, Drexel University
| | - Marissa Fu
- Department of Biology, Drexel University
| | - Riya Kumar
- Department of Biology, Drexel University
| | | | - A Denise R Garcia
- Department of Neurobiology and Anatomy, Drexel University College of Medicine
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2
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Kumari A, Franks NE, Li L, Audu G, Liskowicz S, Johnson JD, Mistretta CM, Allen BL. Distinct expression patterns of Hedgehog signaling components in mouse gustatory system during postnatal tongue development and adult homeostasis. PLoS One 2024; 19:e0294835. [PMID: 38848388 PMCID: PMC11161123 DOI: 10.1371/journal.pone.0294835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 05/22/2024] [Indexed: 06/09/2024] Open
Abstract
The Hedgehog (HH) pathway regulates embryonic development of anterior tongue taste fungiform papilla (FP) and the posterior circumvallate (CVP) and foliate (FOP) taste papillae. HH signaling also mediates taste organ maintenance and regeneration in adults. However, there are knowledge gaps in HH pathway component expression during postnatal taste organ differentiation and maturation. Importantly, the HH transcriptional effectors GLI1, GLI2 and GLI3 have not been investigated in early postnatal stages; the HH receptors PTCH1, GAS1, CDON and HHIP, required to either drive HH pathway activation or antagonism, also remain unexplored. Using lacZ reporter mouse models, we mapped expression of the HH ligand SHH, HH receptors, and GLI transcription factors in FP, CVP and FOP in early and late postnatal and adult stages. In adults we also studied the soft palate, and the geniculate and trigeminal ganglia, which extend afferent fibers to the anterior tongue. Shh and Gas1 are the only components that were consistently expressed within taste buds of all three papillae and the soft palate. In the first postnatal week, we observed broad expression of HH signaling components in FP and adjacent, non-taste filiform (FILIF) papillae in epithelium or stroma and tongue muscles. Notably, we observed elimination of Gli1 in FILIF and Gas1 in muscles, and downregulation of Ptch1 in lingual epithelium and of Cdon, Gas1 and Hhip in stroma from late postnatal stages. Further, HH receptor expression patterns in CVP and FOP epithelium differed from anterior FP. Among all the components, only known positive regulators of HH signaling, SHH, Ptch1, Gli1 and Gli2, were expressed in the ganglia. Our studies emphasize differential regulation of HH signaling in distinct postnatal developmental periods and in anterior versus posterior taste organs, and lay the foundation for functional studies to understand the roles of numerous HH signaling components in postnatal tongue development.
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Affiliation(s)
- Archana Kumari
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Nicole E. Franks
- Department of Cell and Developmental Biology, Medical School, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Libo Li
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Gabrielle Audu
- Department of Cell Biology and Neuroscience, Rowan-Virtua School of Translational Biomedical Engineering and Sciences, Virtua Health College of Medicine and Life Sciences of Rowan University, Stratford, New Jersey, United States of America
| | - Sarah Liskowicz
- Department of Biology, University of Scranton, Scranton, Pennsylvania, United States of America
| | - John D. Johnson
- Rowan-Virtua School of Osteopathic Medicine, Virtua Health College of Medicine and Life Sciences of Rowan University, Stratford, New Jersey, United States of America
| | - Charlotte M. Mistretta
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Benjamin L. Allen
- Department of Cell and Developmental Biology, Medical School, University of Michigan, Ann Arbor, Michigan, United States of America
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3
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Russo M, Pellegrino G, Faure H, Tirou L, Sharif A, Ruat M. Characterization of Sonic Hedgehog transcripts in the adult mouse brain: co-expression with neuronal and oligodendroglial markers. Brain Struct Funct 2024; 229:705-727. [PMID: 38329543 PMCID: PMC10978748 DOI: 10.1007/s00429-023-02756-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 12/29/2023] [Indexed: 02/09/2024]
Abstract
In the adult mammalian brain, astrocytes are proposed to be the major Sonic Hedgehog (Shh)-responsive cells. However, the sources of the Shh molecule mediating activation of the pathway are still poorly characterized. The present work investigates the distribution and phenotype of cells expressing Shh mRNA in the adult mouse brain. Using single-molecule fluorescent in situ hybridization (smfISH), we report much broader expression of Shh transcripts in almost all brain regions than originally reported. We identify Shh mRNA in HuC/D+ neuronal populations, including GABAergic (glutamic acid decarboxylase 67, Gad67), cholinergic (choline acetyltransferase, ChAT), dopaminergic (tyrosine hydroxylase, TH), nitrergic (neuronal nitric oxide synthase, nNOS), and in a small population of oligodendroglial cells expressing Sox10 and Olig2 mRNA transcription factors. Further analysis of Shh mRNA in cerebral cortical and hypothalamic neurons suggests that Shh is also expressed by glutamatergic neurons. Interestingly, we did not observe substantial Desert Hedgehog and Indian Hedgehog mRNA signals, nor Shh signals in S100β+ astrocytes and Iba1+ microglial cells. Collectively, the present work provides the most robust central map of Shh-expressing cells to date and underscores the importance of nitrergic neurons in regulating Shh availability to brain cells. Thus, our study provides a framework for future experiments aimed at better understanding of the functions of Shh signaling in the brain in normal and pathological states, and the characterization of novel regulatory mechanisms of the signaling pathway.
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Affiliation(s)
- Mariagiovanna Russo
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, 91400, Saclay, France
| | - Giuliana Pellegrino
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, 91400, Saclay, France
| | - Hélène Faure
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, 91400, Saclay, France
| | - Linda Tirou
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, 91400, Saclay, France
| | - Ariane Sharif
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience and Cognition, UMR-S 1172, FHU 1000 Days for Health, Lille, France
| | - Martial Ruat
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, 91400, Saclay, France.
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4
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Thumu SCR, Jain M, Soman S, Das S, Verma V, Nandi A, Gutmann DH, Jayaprakash B, Nair D, Clement JP, Marathe S, Ramanan N. SRF-deficient astrocytes provide neuroprotection in mouse models of excitotoxicity and neurodegeneration. eLife 2024; 13:e95577. [PMID: 38289036 PMCID: PMC10857791 DOI: 10.7554/elife.95577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 01/15/2024] [Indexed: 02/10/2024] Open
Abstract
Reactive astrogliosis is a common pathological hallmark of CNS injury, infection, and neurodegeneration, where reactive astrocytes can be protective or detrimental to normal brain functions. Currently, the mechanisms regulating neuroprotective astrocytes and the extent of neuroprotection are poorly understood. Here, we report that conditional deletion of serum response factor (SRF) in adult astrocytes causes reactive-like hypertrophic astrocytes throughout the mouse brain. These SrfGFAP-ERCKO astrocytes do not affect neuron survival, synapse numbers, synaptic plasticity or learning and memory. However, the brains of Srf knockout mice exhibited neuroprotection against kainic-acid induced excitotoxic cell death. Relevant to human neurodegenerative diseases, SrfGFAP-ERCKO astrocytes abrogate nigral dopaminergic neuron death and reduce β-amyloid plaques in mouse models of Parkinson's and Alzheimer's disease, respectively. Taken together, these findings establish SRF as a key molecular switch for the generation of reactive astrocytes with neuroprotective functions that attenuate neuronal injury in the setting of neurodegenerative diseases.
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Affiliation(s)
| | - Monika Jain
- Centre for Neuroscience, Indian Institute of ScienceBangaloreIndia
| | - Sumitha Soman
- Centre for Neuroscience, Indian Institute of ScienceBangaloreIndia
| | - Soumen Das
- Centre for Neuroscience, Indian Institute of ScienceBangaloreIndia
| | - Vijaya Verma
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBangaloreIndia
| | - Arnab Nandi
- Centre for Neuroscience, Indian Institute of ScienceBangaloreIndia
| | - David H Gutmann
- Department of Neurology, Washington University School of MedicineSt. LouisUnited States
| | | | - Deepak Nair
- Centre for Neuroscience, Indian Institute of ScienceBangaloreIndia
| | - James P Clement
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBangaloreIndia
| | - Swananda Marathe
- Centre for Neuroscience, Indian Institute of ScienceBangaloreIndia
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Xie Y, Reid CM, Granados AA, Garcia MT, Dale-Huang F, Hanson SM, Mancia W, Liu J, Adam M, Mosto O, Pisco AO, Alvarez-Buylla A, Harwell CC. Developmental origin and local signals cooperate to determine septal astrocyte identity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.08.561428. [PMID: 37873089 PMCID: PMC10592657 DOI: 10.1101/2023.10.08.561428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Astrocyte specification during development is influenced by both intrinsic and extrinsic factors, but the precise contribution of each remains poorly understood. Here we show that septal astrocytes from Nkx2.1 and Zic4 expressing progenitor zones are allocated into non-overlapping domains of the medial (MS) and lateral septal nuclei (LS) respectively. Astrocytes in these areas exhibit distinctive molecular and morphological features tailored to the unique cellular and synaptic circuit environment of each nucleus. Using single-nucleus (sn) RNA sequencing, we trace the developmental trajectories of cells in the septum and find that neurons and astrocytes undergo region and developmental stage-specific local cell-cell interactions. We show that expression of the classic morphogens Sonic hedgehog (Shh) and Fibroblast growth factors (Fgfs) by MS and LS neurons respectively, functions to promote the molecular specification of local astrocytes in each region. Finally, using heterotopic cell transplantation, we show that both morphological and molecular specifications of septal astrocytes are highly dependent on the local microenvironment, regardless of developmental origins. Our data highlights the complex interplay between intrinsic and extrinsic factors shaping astrocyte identities and illustrates the importance of the local environment in determining astrocyte functional specialization.
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Affiliation(s)
- Yajun Xie
- Department of Neurology, University of California, San Francisco, CA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, CA
| | - Christopher M. Reid
- Department of Neurology, University of California, San Francisco, CA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, CA
- Department of Neurobiology, Harvard Medical School, Boston, MA
- Ph.D. Program in Neuroscience, Harvard University, Boston, MA
| | | | - Miguel Turrero Garcia
- Department of Neurology, University of California, San Francisco, CA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, CA
| | - Fiona Dale-Huang
- Department of Neurology, University of California, San Francisco, CA
- Department of Neurological Surgery, University of California, San Francisco, CA
| | - Sarah M. Hanson
- Department of Neurology, University of California, San Francisco, CA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, CA
| | - Walter Mancia
- Department of Neurology, University of California, San Francisco, CA
- Department of Neurological Surgery, University of California, San Francisco, CA
| | - Jonathan Liu
- Chan Zuckerberg Biohub San Francisco, San Francisco, CA
| | - Manal Adam
- Department of Neurology, University of California, San Francisco, CA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, CA
| | - Olivia Mosto
- Department of Neurobiology, Harvard Medical School, Boston, MA
| | | | - Arturo Alvarez-Buylla
- Department of Neurology, University of California, San Francisco, CA
- Department of Neurological Surgery, University of California, San Francisco, CA
| | - Corey C. Harwell
- Department of Neurology, University of California, San Francisco, CA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, CA
- Chan Zuckerberg Biohub San Francisco, San Francisco, CA
- Lead contact
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Weiss T, Bernard R, Laube G, Rieck J, Eaton MJ, Skatchkov SN, Veh RW. As Verified with the Aid of Biotinylated Spermine, the Brain Cannot Take up Polyamines from the Bloodstream Leaving It Solely Dependent on Local Biosynthesis. Biomolecules 2023; 13:1114. [PMID: 37509150 PMCID: PMC10377363 DOI: 10.3390/biom13071114] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 07/04/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
The importance of polyamines (PAs) for the central nervous system (CNS) is well known. Less clear, however, is where PAs in the brain are derived from. Principally, there are three possibilities: (i) intake by nutrition, release into the bloodstream, and subsequent uptake from CNS capillaries, (ii) production by parenchymatous organs, such as the liver, and again uptake from CNS capillaries, and (iii) uptake of precursors, such as arginine, from the blood and subsequent local biosynthesis of PAs within the CNS. The present investigation aimed to unequivocally answer the question of whether PAs, especially the higher ones like spermidine (SPD) and spermine (SPM), can or cannot be taken up into the brain from the bloodstream. For this purpose, a biotin-labelled analogue of spermine (B-X-SPM) was synthesized, characterized, and used to visualize its uptake into brain cells following application to acute brain slices, to the intraventricular space, or to the bloodstream. In acute brain slices there is strong uptake of B-X-SPM into protoplasmic and none in fibrous-type astrocytes. It is also taken up by neurons but to a lesser degree. Under in vivo conditions, astrocyte uptake of B-X-SPM from the brain interstitial fluid is also intense after intraventricular application. In contrast, following intracardial injection, there is no uptake from the bloodstream, indicating that the brain is completely dependent on the local synthesis of polyamines.
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Affiliation(s)
- Torsten Weiss
- Institut für Integrative Neuroanatomie, Centrum 2, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - René Bernard
- Excellenzcluster Neurocure, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Gregor Laube
- Institut für Integrative Neuroanatomie, Centrum 2, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Julian Rieck
- Institut für Zell- und Neurobiologie, Centrum 2, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Misty J Eaton
- Department of Biochemistry, Universidad Central del Caribe, Bayamón, PR 00956, USA
| | - Serguei N Skatchkov
- Department of Biochemistry, Universidad Central del Caribe, Bayamón, PR 00956, USA
- Department of Physiology, Universidad Central del Caribe, Bayamón, PR 00956, USA
| | - Rüdiger W Veh
- Institut für Zell- und Neurobiologie, Centrum 2, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
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7
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Niedowicz DM, Wang WX, Price DA, Xie K, Patel E, Nelson PT. Impact of thyroid hormone perturbations in adult mice: brain weight and blood vessel changes, gene expression variation, and neurobehavioral outcomes. Neurobiol Aging 2023; 128:74-84. [PMID: 37229849 DOI: 10.1016/j.neurobiolaging.2023.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/24/2023] [Accepted: 04/24/2023] [Indexed: 05/27/2023]
Abstract
Mouse models of hyper- and hypothyroidism were used to examine the effects of thyroid hormone (TH) dyshomeostasis on the aging mammalian brain. 13-14 month-old mice were treated for 4months with either levothyroxine (hyperthyroid) or a propylthiouracil and methimazole combination (PTU/Met; hypothyroid). Hyperthyroid mice performed better on Morris Water Maze than control mice, while hypothyroid mice performed worse. Brain weight was increased in thyroxine-treated, and decreased in PTU/Met-treated animals. The brain weight change was strongly correlated with circulating and tissue T4. Quantitative measurements of microvessels were compared using digital neuropathologic methods. There was an increase in microvessel area in hyperthyroid mice. Hypothyroid mice showed a trend for elevated glial fibrillary acidic protein-immunoreactive astrocytes, indicating an increase in neuroinflammation. Gene expression alterations were associated with TH perturbation and astrocyte-expressed transcripts were particularly affected. For example, expression of Gli2 and Gli3, mediators in the Sonic Hedgehog signaling pathway, were strongly impacted by both treatments. We conclude that TH perturbations produce robust neurobehavioral, pathological, and brain gene expression changes in aging mouse models.
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Affiliation(s)
- Dana M Niedowicz
- Sanders Brown Center on Aging, University of Kentucky, Lexington, KY, USA.
| | - Wang-Xia Wang
- Sanders Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Department of Pathology, Division of Neuropathology, University of Kentucky, Lexington, KY, USA
| | - Douglas A Price
- Sanders Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Kevin Xie
- Department of Biostatistics, University of Kentucky, Lexington, KY, USA
| | - Ela Patel
- Sanders Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Peter T Nelson
- Sanders Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Department of Pathology, Division of Neuropathology, University of Kentucky, Lexington, KY, USA
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Pærregaard SI, Wulff L, Schussek S, Niss K, Mörbe U, Jendholm J, Wendland K, Andrusaite AT, Brulois KF, Nibbs RJB, Sitnik K, Mowat AM, Butcher EC, Brunak S, Agace WW. The small and large intestine contain related mesenchymal subsets that derive from embryonic Gli1 + precursors. Nat Commun 2023; 14:2307. [PMID: 37085516 PMCID: PMC10121680 DOI: 10.1038/s41467-023-37952-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 04/06/2023] [Indexed: 04/23/2023] Open
Abstract
The intestinal lamina propria contains a diverse network of fibroblasts that provide key support functions to cells within their local environment. Despite this, our understanding of the diversity, location and ontogeny of fibroblasts within and along the length of the intestine remains incomplete. Here we show that the small and large intestinal lamina propria contain similar fibroblast subsets that locate in specific anatomical niches. Nevertheless, we find that the transcriptional profile of similar fibroblast subsets differs markedly between the small intestine and colon suggesting region specific functions. We perform in vivo transplantation and lineage-tracing experiments to demonstrate that adult intestinal fibroblast subsets, smooth muscle cells and pericytes derive from Gli1-expressing precursors present in embryonic day 12.5 intestine. Trajectory analysis of single cell RNA-seq datasets of E12.5 and adult mesenchymal cells suggest that adult smooth muscle cells and fibroblasts derive from distinct embryonic intermediates and that adult fibroblast subsets develop in a linear trajectory from CD81+ fibroblasts. Finally, we provide evidence that colonic subepithelial PDGFRαhi fibroblasts comprise several functionally distinct populations that originate from an Fgfr2-expressing fibroblast intermediate. Our results provide insights into intestinal stromal cell diversity, location, function, and ontogeny, with implications for intestinal development and homeostasis.
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Affiliation(s)
- Simone Isling Pærregaard
- Department of Health Technology, Technical University of Denmark, Kemitorvet, 2800 Kgs, Lyngby, Denmark
| | - Line Wulff
- Department of Health Technology, Technical University of Denmark, Kemitorvet, 2800 Kgs, Lyngby, Denmark
| | - Sophie Schussek
- Department of Health Technology, Technical University of Denmark, Kemitorvet, 2800 Kgs, Lyngby, Denmark
| | - Kristoffer Niss
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Urs Mörbe
- Department of Health Technology, Technical University of Denmark, Kemitorvet, 2800 Kgs, Lyngby, Denmark
| | - Johan Jendholm
- Department of Health Technology, Technical University of Denmark, Kemitorvet, 2800 Kgs, Lyngby, Denmark
| | | | - Anna T Andrusaite
- Institute of Infection, immunity and Inflammation, University of Glasgow, Glasgow, Scotland, UK
| | - Kevin F Brulois
- Laboratory of Immunology and Vascular Biology, Department of Pathology, School of Medicine, Stanford University, Stanford, CA, USA
| | - Robert J B Nibbs
- Institute of Infection, immunity and Inflammation, University of Glasgow, Glasgow, Scotland, UK
| | - Katarzyna Sitnik
- Department of Health Technology, Technical University of Denmark, Kemitorvet, 2800 Kgs, Lyngby, Denmark
| | - Allan McI Mowat
- Institute of Infection, immunity and Inflammation, University of Glasgow, Glasgow, Scotland, UK
| | - Eugene C Butcher
- Laboratory of Immunology and Vascular Biology, Department of Pathology, School of Medicine, Stanford University, Stanford, CA, USA
- The Center for Molecular Biology and Medicine, Veterans Affairs Palo Alto Health Care System and the Palo Alto Veterans Institute for Research (PAVIR), Palo Alto, CA, USA
| | - Søren Brunak
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - William W Agace
- Department of Health Technology, Technical University of Denmark, Kemitorvet, 2800 Kgs, Lyngby, Denmark.
- Immunology Section, Lund University, Lund, 221 84, Sweden.
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9
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Markey KM, Saunders JC, Smuts J, von Reyn CR, Garcia ADR. Astrocyte development—More questions than answers. Front Cell Dev Biol 2023; 11:1063843. [PMID: 37051466 PMCID: PMC10083403 DOI: 10.3389/fcell.2023.1063843] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 03/14/2023] [Indexed: 03/28/2023] Open
Abstract
The past 15–20 years has seen a remarkable shift in our understanding of astrocyte contributions to central nervous system (CNS) function. Astrocytes have emerged from the shadows of neuroscience and are now recognized as key elements in a broad array of CNS functions. Astrocytes comprise a substantial fraction of cells in the human CNS. Nevertheless, fundamental questions surrounding their basic biology remain poorly understood. While recent studies have revealed a diversity of essential roles in CNS function, from synapse formation and function to blood brain barrier maintenance, fundamental mechanisms of astrocyte development, including their expansion, migration, and maturation, remain to be elucidated. The coincident development of astrocytes and synapses highlights the need to better understand astrocyte development and will facilitate novel strategies for addressing neurodevelopmental and neurological dysfunction. In this review, we provide an overview of the current understanding of astrocyte development, focusing primarily on mammalian astrocytes and highlight outstanding questions that remain to be addressed. We also include an overview of Drosophila glial development, emphasizing astrocyte-like glia given their close anatomical and functional association with synapses. Drosophila offer an array of sophisticated molecular genetic tools and they remain a powerful model for elucidating fundamental cellular and molecular mechanisms governing astrocyte development. Understanding the parallels and distinctions between astrocyte development in Drosophila and vertebrates will enable investigators to leverage the strengths of each model system to gain new insights into astrocyte function.
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Affiliation(s)
- Kathryn M. Markey
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | | | - Jana Smuts
- Department of Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
| | - Catherine R. von Reyn
- Department of Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - A. Denise R. Garcia
- Department of Biology, Drexel University, Philadelphia, PA, United States
- Department of Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
- *Correspondence: A. Denise R. Garcia,
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10
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Astrocyte heterogeneity and interactions with local neural circuits. Essays Biochem 2023; 67:93-106. [PMID: 36748397 PMCID: PMC10011406 DOI: 10.1042/ebc20220136] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/09/2023] [Accepted: 01/09/2023] [Indexed: 02/08/2023]
Abstract
Astrocytes are ubiquitous within the central nervous system (CNS). These cells possess many individual processes which extend out into the neuropil, where they interact with a variety of other cell types, including neurons at synapses. Astrocytes are now known to be active players in all aspects of the synaptic life cycle, including synapse formation and elimination, synapse maturation, maintenance of synaptic homeostasis and modulation of synaptic transmission. Traditionally, astrocytes have been studied as a homogeneous group of cells. However, recent studies have uncovered a surprising degree of heterogeneity in their development and function, suggesting that astrocytes may be matched to neurons to support local circuits. Hence, a better understanding of astrocyte heterogeneity and its implications are needed to understand brain function.
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11
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Gudkov SV, Burmistrov DE, Kondakova EV, Sarimov RM, Yarkov RS, Franceschi C, Vedunova MV. An emerging role of astrocytes in aging/neuroinflammation and gut-brain axis with consequences on sleep and sleep disorders. Ageing Res Rev 2023; 83:101775. [PMID: 36334910 DOI: 10.1016/j.arr.2022.101775] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 10/05/2022] [Accepted: 10/30/2022] [Indexed: 11/18/2022]
Abstract
Understanding the role of astrocytes in the central nervous system has changed dramatically over the last decade. The accumulating findings indicate that glial cells are involved not only in the maintenance of metabolic and ionic homeostasis and in the implementation of trophic functions but also in cognitive functions and information processing in the brain. Currently, there are some controversies regarding the role of astrocytes in complex processes such as aging of the nervous system and the pathogenesis of age-related neurodegenerative diseases. Many findings confirm the important functional role of astrocytes in age-related brain changes, including sleep disturbance and the development of neurodegenerative diseases and particularly Alzheimer's disease. Until recent years, neurobiological research has focused mainly on neuron-glial interactions, in which individual astrocytes locally modulate neuronal activity and communication between neurons. The review considers the role of astrocytes in the physiology of sleep and as an important "player" in the development of neurodegenerative diseases. In addition, the features of the astrocytic network reorganization during aging are discussed.
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Affiliation(s)
- Sergey V Gudkov
- Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov str., 119991 Moscow, Russia; Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Dmitriy E Burmistrov
- Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov str., 119991 Moscow, Russia.
| | - Elena V Kondakova
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Ruslan M Sarimov
- Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov str., 119991 Moscow, Russia.
| | - Roman S Yarkov
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Claudio Franceschi
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Maria V Vedunova
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
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12
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Activation of Sonic Hedgehog Signaling Promotes Differentiation of Cortical Layer 4 Neurons via Regulation of Their Cell Positioning. J Dev Biol 2022; 10:jdb10040050. [PMID: 36547472 PMCID: PMC9787542 DOI: 10.3390/jdb10040050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/22/2022] [Accepted: 11/23/2022] [Indexed: 11/29/2022] Open
Abstract
Neuronal subtypes in the mammalian cerebral cortex are determined by both intrinsic and extrinsic mechanisms during development. However, the extrinsic cues that are involved in this process remain largely unknown. Here, we investigated the role of sonic hedgehog (Shh) in glutamatergic cortical subtype specification. We found that E14.5-born, but not E15.5-born, neurons with elevated Shh expression frequently differentiated into layer 4 subtypes as judged by the cell positioning and molecular identity. We further found that this effect was achieved indirectly through the regulation of cell positioning rather than the direct activation of layer 4 differentiation programs. Together, we provided evidence that Shh, an extrinsic factor, plays an important role in the specification of cortical superficial layer subtypes.
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13
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Caligiuri SPB, Howe WM, Wills L, Smith ACW, Lei Y, Bali P, Heyer MP, Moen JK, Ables JL, Elayouby KS, Williams M, Fillinger C, Oketokoun Z, Lehmann VE, DiFeliceantonio AG, Johnson PM, Beaumont K, Sebra RP, Ibanez-Tallon I, Kenny PJ. Hedgehog-interacting protein acts in the habenula to regulate nicotine intake. Proc Natl Acad Sci U S A 2022; 119:e2209870119. [PMID: 36346845 PMCID: PMC9674224 DOI: 10.1073/pnas.2209870119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/28/2022] [Indexed: 11/10/2023] Open
Abstract
Hedgehog-interacting protein (HHIP) sequesters Hedgehog ligands to repress Smoothened (SMO)-mediated recruitment of the GLI family of transcription factors. Allelic variation in HHIP confers risk of chronic obstructive pulmonary disease and other smoking-related lung diseases, but underlying mechanisms are unclear. Using single-cell and cell-type-specific translational profiling, we show that HHIP expression is highly enriched in medial habenula (MHb) neurons, particularly MHb cholinergic neurons that regulate aversive behavioral responses to nicotine. HHIP deficiency dysregulated the expression of genes involved in cholinergic signaling in the MHb and disrupted the function of nicotinic acetylcholine receptors (nAChRs) through a PTCH-1/cholesterol-dependent mechanism. Further, CRISPR/Cas9-mediated genomic cleavage of the Hhip gene in MHb neurons enhanced the motivational properties of nicotine in mice. These findings suggest that HHIP influences vulnerability to smoking-related lung diseases in part by regulating the actions of nicotine on habenular aversion circuits.
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Affiliation(s)
- Stephanie P B Caligiuri
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - William M Howe
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Lauren Wills
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Alexander C W Smith
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Ye Lei
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Purva Bali
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Mary P Heyer
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Janna K Moen
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Jessica L Ables
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Karim S Elayouby
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Maya Williams
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Clementine Fillinger
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Zainab Oketokoun
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Vanessa E Lehmann
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | | | - Paul M Johnson
- Department of Information Technology and Electrical Engineering, ETH Zürich, 8092 Zürich, Switzerland
| | - Kristin Beaumont
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Robert P Sebra
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Ines Ibanez-Tallon
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY 10065
| | - Paul J Kenny
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029
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14
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Somaiya RD, Stebbins K, Gingrich EC, Xie H, Campbell JN, Garcia ADR, Fox MA. Sonic hedgehog-dependent recruitment of GABAergic interneurons into the developing visual thalamus. eLife 2022; 11:e79833. [PMID: 36342840 PMCID: PMC9640189 DOI: 10.7554/elife.79833] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 10/10/2022] [Indexed: 11/09/2022] Open
Abstract
Axons of retinal ganglion cells (RGCs) play critical roles in the development of inhibitory circuits in visual thalamus. We previously reported that RGC axons signal astrocytes to induce the expression of fibroblast growth factor 15 (FGF15), a motogen required for GABAergic interneuron migration into visual thalamus. However, how retinal axons induce thalamic astrocytes to generate Fgf15 and influence interneuron migration remains unknown. Here, we demonstrate that impairing RGC activity had little impact on interneuron recruitment into mouse visual thalamus. Instead, our data show that retinal-derived sonic hedgehog (SHH) is essential for interneuron recruitment. Specifically, we show that thalamus-projecting RGCs express SHH and thalamic astrocytes generate downstream components of SHH signaling. Deletion of RGC-derived SHH leads to a significant decrease in Fgf15 expression, as well as in the percentage of interneurons recruited into visual thalamus. Overall, our findings identify a morphogen-dependent neuron-astrocyte signaling mechanism essential for the migration of thalamic interneurons.
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Affiliation(s)
- Rachana Deven Somaiya
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech CarilionRoanokeUnited States
- Graduate Program in Translational Biology, Medicine, and Health, Virginia TechBlacksburgUnited States
| | - Katelyn Stebbins
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech CarilionRoanokeUnited States
- Graduate Program in Translational Biology, Medicine, and Health, Virginia TechBlacksburgUnited States
- Virginia Tech Carilion School of MedicineRoanokeUnited States
| | - Ellen C Gingrich
- Department of Biology, Drexel UniversityPhiladelphiaUnited States
- Department of Neurobiology and Anatomy, Drexel University College of MedicinePhiladelphiaUnited States
| | - Hehuang Xie
- Fralin Life Sciences Institute at Virginia TechBlacksburgUnited States
- School of Neuroscience, College of Science, Virginia TechBlacksburgUnited States
- Genetics, Bioinformatics and Computational Biology Program, Virginia TechBlacksburgUnited States
- Department of Biomedical Sciences and Pathobiology, Virginia–Maryland College of Veterinary MedicineBlacksburgUnited States
| | - John N Campbell
- Department of Biology, University of VirginiaCharlottesvilleUnited States
- Neuroscience Graduate Program, University of VirginiaCharlottesvilleUnited States
| | - A Denise R Garcia
- Department of Biology, Drexel UniversityPhiladelphiaUnited States
- Department of Neurobiology and Anatomy, Drexel University College of MedicinePhiladelphiaUnited States
| | - Michael A Fox
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech CarilionRoanokeUnited States
- School of Neuroscience, College of Science, Virginia TechBlacksburgUnited States
- Department of Biological Sciences, College of Science, Virginia TechBlacksburgUnited States
- Department of Pediatrics, Virginia Tech Carilion School of MedicineRoanokeUnited States
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15
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A systemic cell stress signal confers neuronal resilience toward oxidative stress in a Hedgehog-dependent manner. Cell Rep 2022; 41:111488. [PMID: 36260999 PMCID: PMC9623505 DOI: 10.1016/j.celrep.2022.111488] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/04/2022] [Accepted: 09/21/2022] [Indexed: 11/22/2022] Open
Abstract
Cells possess several conserved adaptive mechanisms to respond to stress. Stress signaling is initiated to reestablish cellular homeostasis, but its effects on the tissue or systemic levels are far less understood. We report that the secreted luminal domain of the endoplasmic reticulum (ER) stress transducer CREB3L2 (which we name TAILS [transmissible activator of increased cell livability under stress]) is an endogenous, cell non-autonomous activator of neuronal resilience. In response to oxidative insults, neurons secrete TAILS, which potentiates hedgehog signaling through direct interaction with Sonic hedgehog (SHH) and its receptor PTCH1, leading to improved antioxidant signaling and mitochondrial function in neighboring neurons. In an in vivo model of ischemic brain injury, administration of TAILS enables survival of CNS neurons and fully preserves cognitive function in behavioral tests. Our findings reveal an SHH-mediated, cell non-autonomous branch of cellular stress signaling that confers resilience to oxidative stress in the mature brain, providing protection from ischemic neurodegeneration. Whether and how neurons can communicate stress to other neurons is poorly understood. Chung et al. demonstrate that oxidative stress in neurons leads to secretion of cell non-autonomous stress signaling protein. This protein, TAILS, induces neuronal resilience against cell stress in recipient cells in an SHH-dependent manner.
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16
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Wang J, Ware K, Bedolla A, Allgire E, Turcato FC, Weed M, Sah R, Luo Y. Disruption of Sonic Hedgehog Signaling Accelerates Age-Related Neurogenesis Decline and Abolishes Stroke-Induced Neurogenesis and Leads to Increased Anxiety Behavior in Stroke Mice. Transl Stroke Res 2022; 13:830-844. [PMID: 35146631 PMCID: PMC10114538 DOI: 10.1007/s12975-022-00994-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/10/2022] [Accepted: 01/31/2022] [Indexed: 02/03/2023]
Abstract
Sonic Hedgehog (SHH) signaling has a critical role in mediating developmental neurogenesis and has been implicated in adult subventricular (SVZ) neurogenesis. However, the precise role of Smoothened (SMO) receptor-mediated SHH signaling in adult neurogenesis during aging especially in hippocampal subgranular zone (SGZ) neurogenesis remains undefined. Additionally, our previous study showed that stimulation of SHH signaling post-stroke leads to increased neurogenesis and improved behavioral functions after stroke. However, it is not clear whether SHH signaling in neural stem cells (NSCs) is required for stroke-induced neurogenesis and functional recovery post-stroke. In this study, using conditional knockout (cKO) of SHH signaling receptor Smo gene in NSCs, we show a decreased neurogenesis at both SVZ and SGZ in young-adult mice and an accelerated depletion of neurogenic cells in the process of aging suggesting that SHH signaling is critical in maintaining neurogenesis during aging. Behavior studies revealed that compromised neurogenesis in Smo cKO mice leads to increased anxiety/depression-like behaviors without affecting general locomotor function or spatial and fear-related learning. Importantly, we also show that NSCs with a cKO of SHH signaling abolishes stroke-induced neurogenesis in Smo cKO mice. Compared to control mice, Smo cKO mice also show delayed motor function recovery and increased anxiety level after stroke. Our data highlights the essential role of Smo function in regulating adult neurogenesis and emotional behaviors during both aging and CNS injury such as stroke.
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Affiliation(s)
- Jiapeng Wang
- Department of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of Cincinnati, Cincinnati, OH, 45267, USA
- Department of Molecular Genetics, Biochemistry and Microbiology, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Kierra Ware
- Department of Molecular Genetics, Biochemistry and Microbiology, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Alicia Bedolla
- Department of Molecular Genetics, Biochemistry and Microbiology, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
- Neuroscience Graduate Program, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Emily Allgire
- Neuroscience Graduate Program, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
- Department of Pharmacology & Systems Physiology, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Flavia Correa Turcato
- Department of Molecular Genetics, Biochemistry and Microbiology, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Maxwell Weed
- Department of Molecular Genetics, Biochemistry and Microbiology, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Renu Sah
- Neuroscience Graduate Program, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
- Department of Pharmacology & Systems Physiology, University of Cincinnati, Cincinnati, OH, 45267, USA
- Cincinnati VA Medical Center, Cincinnati, OH, 45220, USA
| | - Yu Luo
- Department of Molecular Genetics, Biochemistry and Microbiology, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA.
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17
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Bostock MP, Prasad AR, Donoghue A, Fernandes VM. Photoreceptors generate neuronal diversity in their target field through a Hedgehog morphogen gradient in Drosophila. eLife 2022; 11:78093. [PMID: 36004721 PMCID: PMC9507128 DOI: 10.7554/elife.78093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
Defining the origin of neuronal diversity is a major challenge in developmental neurobiology. The Drosophila visual system is an excellent paradigm to study how cellular diversity is generated. Photoreceptors from the eye disc grow their axons into the optic lobe and secrete Hedgehog (Hh) to induce the lamina, such that for every unit eye there is a corresponding lamina unit made up of post-mitotic precursors stacked into columns. Each differentiated column contains five lamina neuron types (L1-L5), making it the simplest neuropil in the optic lobe, yet how this diversity is generated was unknown. Here, we found that Hh pathway activity is graded along the distal-proximal axis of lamina columns and further determined that this gradient in pathway activity arises from a gradient of Hh ligand. We manipulated Hh pathway activity cell-autonomously in lamina precursors and non-cell autonomously by inactivating the Hh ligand, and by knocking it down in photoreceptors. These manipulations showed that different thresholds of activity specify unique cell identities, with more proximal cell types specified in response to progressively lower Hh levels. Thus, our data establish that Hh acts as a morphogen to pattern the lamina. Although, this is the first such report during Drosophila nervous system development, our work uncovers a remarkable similarity with the vertebrate neural tube, which is patterned by Sonic Hedgehog. Altogether, we show that differentiating neurons can regulate the neuronal diversity of their distant target fields through morphogen gradients.
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Affiliation(s)
- Matthew P Bostock
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Anadika R Prasad
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Alicia Donoghue
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Vilaiwan M Fernandes
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
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18
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Scales MK, Velez-Delgado A, Steele NG, Schrader HE, Stabnick AM, Yan W, Mercado Soto NM, Nwosu ZC, Johnson C, Zhang Y, Salas-Escabillas DJ, Menjivar RE, Maurer HC, Crawford HC, Bednar F, Olive KP, Pasca di Magliano M, Allen BL. Combinatorial Gli activity directs immune infiltration and tumor growth in pancreatic cancer. PLoS Genet 2022; 18:e1010315. [PMID: 35867772 PMCID: PMC9348714 DOI: 10.1371/journal.pgen.1010315] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 08/03/2022] [Accepted: 06/27/2022] [Indexed: 01/16/2023] Open
Abstract
Proper Hedgehog (HH) signaling is essential for embryonic development, while aberrant HH signaling drives pediatric and adult cancers. HH signaling is frequently dysregulated in pancreatic cancer, yet its role remains controversial, with both tumor-promoting and tumor-restraining functions reported. Notably, the GLI family of HH transcription factors (GLI1, GLI2, GLI3), remain largely unexplored in pancreatic cancer. We therefore investigated the individual and combined contributions of GLI1-3 to pancreatic cancer progression. At pre-cancerous stages, fibroblast-specific Gli2/Gli3 deletion decreases immunosuppressive macrophage infiltration and promotes T cell infiltration. Strikingly, combined loss of Gli1/Gli2/Gli3 promotes macrophage infiltration, indicating that subtle changes in Gli expression differentially regulate immune infiltration. In invasive tumors, Gli2/Gli3 KO fibroblasts exclude immunosuppressive myeloid cells and suppress tumor growth by recruiting natural killer cells. Finally, we demonstrate that fibroblasts directly regulate macrophage and T cell migration through the expression of Gli-dependent cytokines. Thus, the coordinated activity of GLI1-3 directs the fibroinflammatory response throughout pancreatic cancer progression.
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Affiliation(s)
- Michael K. Scales
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Ashley Velez-Delgado
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Nina G. Steele
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Hannah E. Schrader
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Anna M. Stabnick
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Wei Yan
- Department of Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Nayanna M. Mercado Soto
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Zeribe C. Nwosu
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Craig Johnson
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Yaqing Zhang
- Department of Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
- Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | | | - Rosa E. Menjivar
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, Michigan, United States of America
| | - H. Carlo Maurer
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York city, New York, United States of America
- Internal Medicine II, School of Medicine, Technische Universität München, Munich, Germany
| | - Howard C. Crawford
- Department of Surgery, Henry Ford Health System, Detroit, Michigan, United States of America
| | - Filip Bednar
- Department of Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
- Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Kenneth P. Olive
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York city, New York, United States of America
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York city, New York, United States of America
| | - Marina Pasca di Magliano
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
- Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Benjamin L. Allen
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
- Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan, United States of America
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19
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Burda JE, O'Shea TM, Ao Y, Suresh KB, Wang S, Bernstein AM, Chandra A, Deverasetty S, Kawaguchi R, Kim JH, McCallum S, Rogers A, Wahane S, Sofroniew MV. Divergent transcriptional regulation of astrocyte reactivity across disorders. Nature 2022; 606:557-564. [PMID: 35614216 PMCID: PMC10027402 DOI: 10.1038/s41586-022-04739-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 04/07/2022] [Indexed: 01/30/2023]
Abstract
Astrocytes respond to injury and disease in the central nervous system with reactive changes that influence the outcome of the disorder1-4. These changes include differentially expressed genes (DEGs) whose contextual diversity and regulation are poorly understood. Here we combined biological and informatic analyses, including RNA sequencing, protein detection, assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) and conditional gene deletion, to predict transcriptional regulators that differentially control more than 12,000 DEGs that are potentially associated with astrocyte reactivity across diverse central nervous system disorders in mice and humans. DEGs associated with astrocyte reactivity exhibited pronounced heterogeneity across disorders. Transcriptional regulators also exhibited disorder-specific differences, but a core group of 61 transcriptional regulators was identified as common across multiple disorders in both species. We show experimentally that DEG diversity is determined by combinatorial, context-specific interactions between transcriptional regulators. Notably, the same reactivity transcriptional regulators can regulate markedly different DEG cohorts in different disorders; changes in the access of transcriptional regulators to DNA-binding motifs differ markedly across disorders; and DEG changes can crucially require multiple reactivity transcriptional regulators. We show that, by modulating reactivity, transcriptional regulators can substantially alter disorder outcome, implicating them as therapeutic targets. We provide searchable resources of disorder-related reactive astrocyte DEGs and their predicted transcriptional regulators. Our findings show that transcriptional changes associated with astrocyte reactivity are highly heterogeneous and are customized from vast numbers of potential DEGs through context-specific combinatorial transcriptional-regulator interactions.
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Affiliation(s)
- Joshua E Burda
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
- Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Timothy M O'Shea
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Yan Ao
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Keshav B Suresh
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Shinong Wang
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Alexander M Bernstein
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Ashu Chandra
- Department of Computer Science, University of California Los Angeles, Los Angeles, CA, USA
| | - Sandeep Deverasetty
- Department of Psychiatry, University of California Los Angeles, Los Angeles, CA, USA
- Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA
| | - Riki Kawaguchi
- Department of Psychiatry, University of California Los Angeles, Los Angeles, CA, USA
- Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA
| | - Jae H Kim
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Sarah McCallum
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Alexandra Rogers
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Shalaka Wahane
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Michael V Sofroniew
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
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20
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Okuda H, Ishikawa T, Hori K, Kwankaew N, Ozaki N. Hedgehog signaling plays a crucial role in hyperalgesia associated with neuropathic pain in mice. J Neurochem 2022; 162:207-220. [PMID: 35437761 DOI: 10.1111/jnc.15613] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 03/24/2022] [Accepted: 03/27/2022] [Indexed: 11/29/2022]
Abstract
Neuropathic pain is a debilitating chronic syndrome of the nervous system caused by nerve injury. In Drosophila, the Hedgehog (Hh) signaling pathway is related to increased pain sensitivity (hyperalgesia) but does not affect the baseline nociceptive threshold. In general, the contribution of the Hh signaling pathway to neuropathic pain in vertebrates is a highly debated issue. Alternatively, we investigated the potential role of Hh signaling in mechanical allodynia using a mouse model of neuropathic pain. Seven days after spinal nerve-transection (SNT) surgery, microglial activation increased in the ipsilateral spinal dorsal horn compared with that in the sham group; however, 21 days after surgery, microglial activation decreased. Contrastingly, astrocyte activation in the spinal cord did not differ between the groups. On day 21 of postsurgery, the SNT group showed marked upregulation of sonic hedgehog expression in peripheral glial cells but not in dorsal root ganglion (DRG) neurons. Intrathecal administration of the Hh signaling inhibitor vismodegib attenuated the mechanical allodynia observed on day 21 postsurgery. Conversely, intrathecal treatment with the Hh signaling activator smoothened agonist in naive mice induced mechanical allodynia, which was abolished by the ATP transporter inhibitor clodronate. Moreover, inhibition of Hh signaling by pretreatment with vismodegib significantly reduced ATP secretion and the frequency/number of spontaneous elevations of intracellular calcium ion levels in cultured DRG cells. Thus, the Hh signaling pathway appears to modulate the neural activity of DRG neurons via ATP release, and it plays an important role in sustaining mechanical allodynia and hypersensitivity in a mouse model of neuropathic pain.
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Affiliation(s)
- Hiroaki Okuda
- Department of Functional Anatomy, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Tatsuya Ishikawa
- Department of Functional Anatomy, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Kiyomi Hori
- Department of Functional Anatomy, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Nichakarn Kwankaew
- Department of Functional Anatomy, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Noriyuki Ozaki
- Department of Functional Anatomy, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
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21
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Smith AE, Sigurbjörnsdóttir ES, Steingrímsson E, Sigurbjörnsdóttir S. Hedgehog signalling in bone and osteoarthritis: the role of Smoothened and cholesterol. FEBS J 2022. [PMID: 35305060 DOI: 10.1111/febs.16440] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/25/2022] [Accepted: 03/17/2022] [Indexed: 12/12/2022]
Abstract
Hedgehog signalling is essential for development, crucial for normal anatomical arrangement and activated during tissue damage repair. Dysregulation of hedgehog signalling is associated with cancer, developmental disorders and other diseases including osteoarthritis (OA). The hedgehog gene was first discovered in Drosophila melanogaster, and the pathway is evolutionarily conserved in most animals. Although there are several hedgehog ligands with different protein expression patterns, they share a common plasma membrane receptor, Patched1 and hedgehog signalling pathway activation is transduced through the G-protein-coupled receptor-like protein Smoothened (SMO) and downstream effectors. Functional assays revealed that activation of SMO is dependent on sterol binding, and cholesterol was observed bound to SMO in crystallography experiments. In vertebrates, hedgehog signalling coordinates endochondral ossification and balances osteoblast and osteoclast activation to maintain homeostasis. A recently discovered mutation of SMO in humans (SMOR173C ) is predicted to alter cholesterol binding and is associated with a higher risk of hip OA. Functional studies in mice and human tissue analysis provide evidence that hedgehog signalling is pathologically activated in chondrocytes of osteoarthritic cartilage.
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Affiliation(s)
- Abbi Elise Smith
- Faculty of Medicine, Department of Biochemistry and Molecular Biology, University of Iceland, Reykjavik, Iceland
| | - Elín Sóley Sigurbjörnsdóttir
- Faculty of Medicine, Department of Biochemistry and Molecular Biology, University of Iceland, Reykjavik, Iceland
| | - Eiríkur Steingrímsson
- Faculty of Medicine, Department of Biochemistry and Molecular Biology, University of Iceland, Reykjavik, Iceland
| | - Sara Sigurbjörnsdóttir
- Faculty of Medicine, Department of Biochemistry and Molecular Biology, University of Iceland, Reykjavik, Iceland.,Faculty of Life and Environmental Sciences, School of Engineering and Natural Sciences, BioMedical Center, University of Iceland, Reykjavik, Iceland
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22
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Xie Y, Kuan AT, Wang W, Herbert ZT, Mosto O, Olukoya O, Adam M, Vu S, Kim M, Tran D, Gómez N, Charpentier C, Sorour I, Lacey TE, Tolstorukov MY, Sabatini BL, Lee WCA, Harwell CC. Astrocyte-neuron crosstalk through Hedgehog signaling mediates cortical synapse development. Cell Rep 2022; 38:110416. [PMID: 35196485 PMCID: PMC8962654 DOI: 10.1016/j.celrep.2022.110416] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 11/04/2021] [Accepted: 01/28/2022] [Indexed: 12/12/2022] Open
Abstract
Neuron-glia interactions play a critical role in the regulation of synapse formation and circuit assembly. Here we demonstrate that canonical Sonic hedgehog (Shh) pathway signaling in cortical astrocytes acts to coordinate layer-specific synaptic connectivity. We show that the Shh receptor Ptch1 is expressed by cortical astrocytes during development and that Shh signaling is necessary and sufficient to promote the expression of genes involved in regulating synaptic development and layer-enriched astrocyte molecular identity. Loss of Shh in layer V neurons reduces astrocyte complexity and coverage by astrocytic processes in tripartite synapses; conversely, cell-autonomous activation of Shh signaling in astrocytes promotes cortical excitatory synapse formation. Furthermore, Shh-dependent genes Lrig1 and Sparc distinctively contribute to astrocyte morphology and synapse formation. Together, these results suggest that Shh secreted from deep-layer cortical neurons acts to specialize the molecular and functional features of astrocytes during development to shape circuit assembly and function. Xie et al. show that Sonic hedgehog expressed by cortical layer V neurons signals to Ptch1-expressing astrocytes where it is necessary to promote the expression of layer-enriched astrocyte gene networks that control synapse formation and astrocyte morphological complexity.
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Affiliation(s)
- Yajun Xie
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Aaron T Kuan
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Wengang Wang
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Zachary T Herbert
- Molecular Biology Core Facilities, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Olivia Mosto
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Olubusola Olukoya
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Manal Adam
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Steve Vu
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Minsu Kim
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Diana Tran
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Nicolás Gómez
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Claire Charpentier
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Ingie Sorour
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Tiara E Lacey
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Michael Y Tolstorukov
- Department of Informatics and Analytics, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Bernardo L Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Wei-Chung Allen Lee
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - Corey C Harwell
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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23
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The Sonic Hedgehog Pathway Modulates Survival, Proliferation, and Differentiation of Neural Progenitor Cells under Inflammatory Stress In Vitro. Cells 2022; 11:cells11040736. [PMID: 35203385 PMCID: PMC8869809 DOI: 10.3390/cells11040736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 01/27/2022] [Accepted: 02/17/2022] [Indexed: 12/15/2022] Open
Abstract
The Sonic Hedgehog protein (Shh) has been extensively researched since its discovery in 1980. Its crucial role in early neurogenesis and endogenous stem cells of mature brains, as well as its recently described neuroprotective features, implicate further important effects on neuronal homeostasis. Here, we investigate its potential role in the survival, proliferation, and differentiation of neural precursors cells (NPCs) under inflammatory stress as a potential adjunct for NPC-transplantation strategies in spinal cord injury (SCI) treatment. To this end, we simulated an inflammatory environment in vitro using lipopolysaccharide (LPS) and induced the Shh-pathway using recombinant Shh or blocked it using Cyclopamine, a potent Smo inhibitor. We found that Shh mediates the proliferation and neuronal differentiation potential of NPCs in vitro, even in an inflammatory stress environment mimicking the subacute phase after SCI. At the same time, our results indicate that a reduction of the Shh-pathway activation by blockage with Cyclopamine is associated with reduced NPC-survival, reduced neuronal differentiation and increased astroglial differentiation. Shh might thus, play a role in endogenous NPC-mediated neuroregeneration or even be a potent conjunct to NPC-based therapies in the inflammatory environment after SCI.
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24
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Allahyari RV, Heinsinger NM, Hwang D, Jaffe DA, Rasouli J, Shiers S, Thomas SJ, Price TJ, Rostami A, Lepore AC. Response of Astrocyte Subpopulations Following Spinal Cord Injury. Cells 2022; 11:cells11040721. [PMID: 35203371 PMCID: PMC8870235 DOI: 10.3390/cells11040721] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/15/2022] [Accepted: 02/16/2022] [Indexed: 12/16/2022] Open
Abstract
There is growing appreciation for astrocyte heterogeneity both across and within central nervous system (CNS) regions, as well as between intact and diseased states. Recent work identified multiple astrocyte subpopulations in mature brain. Interestingly, one subpopulation (Population C) was shown to possess significantly enhanced synaptogenic properties in vitro, as compared with other astrocyte subpopulations of adult cortex and spinal cord. Following spinal cord injury (SCI), damaged neurons lose synaptic connections with neuronal partners, resulting in persistent functional loss. We determined whether SCI induces an enhanced synaptomodulatory astrocyte phenotype by shifting toward a greater proportion of Population C cells and/or increasing expression of relevant synapse formation-associated genes within one or more astrocyte subpopulations. Using flow cytometry and RNAscope in situ hybridization, we found that astrocyte subpopulation distribution in the spinal cord did not change to a selectively synaptogenic phenotype following mouse cervical hemisection-type SCI. We also found that spinal cord astrocytes expressed synapse formation-associated genes to a similar degree across subpopulations, as well as in an unchanged manner between uninjured and SCI conditions. Finally, we confirmed these astrocyte subpopulations are also present in the human spinal cord in a similar distribution as mouse, suggesting possible conservation of spinal cord astrocyte heterogeneity across species.
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Affiliation(s)
- R. Vivian Allahyari
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (R.V.A.); (N.M.H.); (D.A.J.); (S.J.T.)
| | - Nicolette M. Heinsinger
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (R.V.A.); (N.M.H.); (D.A.J.); (S.J.T.)
| | - Daniel Hwang
- Department of Neurology, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (D.H.); (J.R.); (A.R.)
| | - David A. Jaffe
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (R.V.A.); (N.M.H.); (D.A.J.); (S.J.T.)
| | - Javad Rasouli
- Department of Neurology, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (D.H.); (J.R.); (A.R.)
| | - Stephanie Shiers
- Center for Advanced Pain Studies, Department of Neuroscience, University of Texas at Dallas, Richardson, TX 75080, USA; (S.S.); (T.J.P.)
| | - Samantha J. Thomas
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (R.V.A.); (N.M.H.); (D.A.J.); (S.J.T.)
| | - Theodore J. Price
- Center for Advanced Pain Studies, Department of Neuroscience, University of Texas at Dallas, Richardson, TX 75080, USA; (S.S.); (T.J.P.)
| | - Abdolmohamad Rostami
- Department of Neurology, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (D.H.); (J.R.); (A.R.)
| | - Angelo C. Lepore
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; (R.V.A.); (N.M.H.); (D.A.J.); (S.J.T.)
- Correspondence: ; Tel.: +1-215-503-5864
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25
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Bugiani M, Plug BC, Man JHK, Breur M, van der Knaap MS. Heterogeneity of white matter astrocytes in the human brain. Acta Neuropathol 2022; 143:159-177. [PMID: 34878591 DOI: 10.1007/s00401-021-02391-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 11/17/2021] [Accepted: 11/28/2021] [Indexed: 12/12/2022]
Abstract
Astrocytes regulate central nervous system development, maintain its homeostasis and orchestrate repair upon injury. Emerging evidence support functional specialization of astroglia, both between and within brain regions. Different subtypes of gray matter astrocytes have been identified, yet molecular and functional diversity of white matter astrocytes remains largely unexplored. Nonetheless, their important and diverse roles in maintaining white matter integrity and function are well recognized. Compelling evidence indicate that impairment of normal astrocytic function and their response to injury contribute to a wide variety of diseases, including white matter disorders. In this review, we highlight our current understanding of astrocyte heterogeneity in the white matter of the mammalian brain and how an interplay between developmental origins and local environmental cues contribute to astroglial diversification. In addition, we discuss whether, and if so, how, heterogeneous astrocytes could contribute to white matter function in health and disease and focus on the sparse human research data available. We highlight four leukodystrophies primarily due to astrocytic dysfunction, the so-called astrocytopathies. Insight into the role of astroglial heterogeneity in both healthy and diseased white matter may provide new avenues for therapies aimed at promoting repair and restoring normal white matter function.
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26
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Gingrich EC, Case K, Garcia ADR. A subpopulation of astrocyte progenitors defined by Sonic hedgehog signaling. Neural Dev 2022; 17:2. [PMID: 35027088 PMCID: PMC8759290 DOI: 10.1186/s13064-021-00158-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 12/20/2021] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND The molecular signaling pathway, Sonic hedgehog (Shh), is critical for the proper development of the central nervous system. The requirement for Shh signaling in neuronal and oligodendrocyte development in the developing embryo are well established. However, Shh activity is found in discrete subpopulations of astrocytes in the postnatal and adult brain. Whether Shh signaling plays a role in astrocyte development is not well understood. METHODS Here, we use a genetic inducible fate mapping approach to mark and follow a population of glial progenitor cells expressing the Shh target gene, Gli1, in the neonatal and postnatal brain. RESULTS In the neonatal brain, Gli1-expressing cells are found in the dorsolateral corner of the subventricular zone (SVZ), a germinal zone harboring astrocyte progenitor cells. Our data show that these cells give rise to half of the cortical astrocyte population, demonstrating their substantial contribution to the cellular composition of the cortex. Further, these data suggest that the cortex harbors astrocytes from different lineages. Gli1 lineage astrocytes are distributed across all cortical layers, positioning them for broad influence over cortical circuits. Finally, we show that Shh activity recurs in mature astrocytes in a lineage-independent manner, suggesting cell-type dependent roles of the pathway in driving astrocyte development and function. CONCLUSION These data identify a novel role for Shh signaling in cortical astrocyte development and support a growing body of evidence pointing to astrocyte heterogeneity.
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Affiliation(s)
- Ellen C Gingrich
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
- Drexel University, 3245 Chestnut St. PISB 422, Philadelphia, PA, 19104, USA
| | - Kendra Case
- Drexel University, 3245 Chestnut St. PISB 422, Philadelphia, PA, 19104, USA
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, 19129, USA
| | - A Denise R Garcia
- Drexel University, 3245 Chestnut St. PISB 422, Philadelphia, PA, 19104, USA.
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, 19129, USA.
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27
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GLI3 Is Required for OLIG2+ Progeny Production in Adult Dorsal Neural Stem Cells. Cells 2022; 11:cells11020218. [PMID: 35053334 PMCID: PMC8773499 DOI: 10.3390/cells11020218] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 12/19/2021] [Accepted: 12/21/2021] [Indexed: 02/05/2023] Open
Abstract
The ventricular-subventricular zone (V-SVZ) is a postnatal germinal niche. It holds a large population of neural stem cells (NSCs) that generate neurons and oligodendrocytes for the olfactory bulb and (primarily) the corpus callosum, respectively. These NSCs are heterogeneous and generate different types of neurons depending on their location. Positional identity among NSCs is thought to be controlled in part by intrinsic pathways. However, extrinsic cell signaling through the secreted ligand Sonic hedgehog (Shh) is essential for neurogenesis in both the dorsal and ventral V-SVZ. Here we used a genetic approach to investigate the role of the transcription factors GLI2 and GLI3 in the proliferation and cell fate of dorsal and ventral V-SVZ NSCs. We find that while GLI3 is expressed in stem cell cultures from both dorsal and ventral V-SVZ, the repressor form of GLI3 is more abundant in dorsal V-SVZ. Despite this high dorsal expression and the requirement for other Shh pathway members, GLI3 loss affects the generation of ventrally-, but not dorsally-derived olfactory interneurons in vivo and does not affect trilineage differentiation in vitro. However, loss of GLI3 in the adult dorsal V-SVZ in vivo results in decreased numbers of OLIG2-expressing progeny, indicating a role in gliogenesis.
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28
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Verkhratsky A, Li B, Scuderi C, Parpura V. Principles of Astrogliopathology. ADVANCES IN NEUROBIOLOGY 2021; 26:55-73. [PMID: 34888830 DOI: 10.1007/978-3-030-77375-5_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The role of astrocytes in the nervous system pathology was early on embraced by neuroscientists at end of the nineteenth and the beginning of the twentieth century, only to be pushed aside by neurone-centric dogmas during most of the twentieth century. However, the last decade of the twentieth century and the twenty-first century have brought the astroglial "renaissance", which has put astroglial cells as key players in pathophysiology of most if not all disorders of the nervous system and has regarded astroglia as a fertile ground for therapeutic intervention.Astrocytic contribution to neuropathology can be primary, whereby cell-autonomous changes, such as mutations in gene encoding for glial fibrillary acidic protein, can drive the pathologic progression, in this example, Alexander disease. They can also be secondary, when astrocytes respond to a variety of insults to the nervous tissue. Regardless of their origin, being cell-autonomous or not, changes in astroglia that occur in pathology, that is, astrogliopathology, can be contemporary and arbitrary classified into four forms: (i) reactive astrogliosis, (ii) astrocytic atrophy with loss of function, (iii) pathological remodelling of astrocytes and (iv) astrodegeneration morphologically manifested as clasmatodendrosis. Inevitably, as with any other classification, this classification of astrogliopathology awaits its revision that shall be rooted in new discoveries and concepts.
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Affiliation(s)
- Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.
- Achucarro Center for Neuroscience, IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
| | - Baoman Li
- Practical Teaching Center, School of Forensic Medicine, China Medical University, Shenyang, China
| | - Caterina Scuderi
- Department of Physiology and Pharmacology "Vittorio Erspamer", SAPIENZA University of Rome, Rome, Italy
| | - Vladimir Parpura
- Department of Neurobiology, The University of Alabama at Birmingham, Birmingham, AL, USA
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29
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Samanta J, Silva HM, Lafaille JJ, Salzer JL. Transcriptomic analysis of loss of Gli1 in neural stem cells responding to demyelination in the mouse brain. Sci Data 2021; 8:278. [PMID: 34711861 PMCID: PMC8553940 DOI: 10.1038/s41597-021-01063-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 09/10/2021] [Indexed: 12/11/2022] Open
Abstract
In the adult mammalian brain, Gli1 expressing neural stem cells reside in the subventricular zone and their progeny are recruited to sites of demyelination in the white matter where they generate new oligodendrocytes, the myelin forming cells. Remarkably, genetic loss or pharmacologic inhibition of Gli1 enhances the efficacy of remyelination by these neural stem cells. To understand the molecular mechanisms involved, we performed a transcriptomic analysis of this Gli1-pool of neural stem cells. We compared murine NSCs with either intact or deficient Gli1 expression from adult mice on a control diet or on a cuprizone diet which induces widespread demyelination. These data will be a valuable resource for identifying therapeutic targets for enhancing remyelination in demyelinating diseases like multiple sclerosis.
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Affiliation(s)
- Jayshree Samanta
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University School of Medicine, New York, NY, 10016, USA.
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, 53706, USA.
| | - Hernandez Moura Silva
- The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, New York, 10016, USA
| | - Juan J Lafaille
- The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, New York, 10016, USA
| | - James L Salzer
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University School of Medicine, New York, NY, 10016, USA.
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30
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The Hedgehog Signaling Pathway is Expressed in the Adult Mouse Hypothalamus and Modulated by Fasting. eNeuro 2021; 8:ENEURO.0276-21.2021. [PMID: 34535504 PMCID: PMC8482854 DOI: 10.1523/eneuro.0276-21.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/28/2021] [Accepted: 08/10/2021] [Indexed: 11/21/2022] Open
Abstract
The hedgehog signaling pathway is best known for its role in developmental patterning of the neural tube and limb bud. More recently, hedgehog signaling has been recognized for its roles in growth of adult tissues and maintenance of progenitor cell niches. However, the role of hedgehog signaling in fully differentiated cells like neurons in the adult brain is less clear. In mammals, coordination of hedgehog pathway activity relies on primary cilia and patients with ciliopathies such as Bardet–Biedl and Alström syndrome exhibit clinical features clearly attributable to errant hedgehog such as polydactyly. However, these ciliopathies also present with features not clearly associated with hedgehog signaling such as hyperphagia-associated obesity. How hedgehog signaling may contribute to feeding behavior is complex and unclear, but cilia are critical for proper energy homeostasis. Here, we provide a detailed analysis of the expression of core components of the hedgehog signaling pathway in the adult mouse hypothalamus with an emphasis on feeding centers. We show that hedgehog pathway genes continue to be expressed in differentiated neurons important for the regulation of feeding behavior. Furthermore, we demonstrate for the first time that pathway activity is regulated at the transcriptional level by fasting. These data suggest that hedgehog signaling is involved in the proper functioning of brain regions that regulate feeding behavior and that hedgehog pathway dysfunction may play a role in the obesity observed in certain ciliopathies.
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31
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Shin H, Kawai HD. Sensitive timing of undifferentiation in oligodendrocyte progenitor cells and their enhanced maturation in primary visual cortex of binocularly enucleated mice. PLoS One 2021; 16:e0257395. [PMID: 34534256 PMCID: PMC8448312 DOI: 10.1371/journal.pone.0257395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 08/30/2021] [Indexed: 11/19/2022] Open
Abstract
Sensory experience modulates proliferation, differentiation, and migration of oligodendrocyte progenitor cells (OPCs). In the mouse primary visual cortex (V1), visual deprivation-dependent modulation of OPCs has not been demonstrated. Here, we demonstrate that undifferentiated OPCs developmentally peaked around postnatal day (P) 25, and binocular enucleation (BE) from the time of eye opening (P14-15) elevated symmetrically-divided undifferentiated OPCs in a reversible G0/G1 state even more at the bottom lamina of the cortex by reducing maturing oligodendrocyte (OL) lineage cells. Experiments using the sonic hedgehog (Shh) signaling inhibitor cyclopamine in vivo suggested that Shh signaling pathway was involved in the BE-induced undifferentiation process. The undifferentiated OPCs then differentiated within 5 days, independent of the experience, becoming mostly quiescent cells in control mice, while altering the mode of sister cell symmetry and forming quiescent as well as maturing cells in the enucleated mice. At P50, BE increased mature OLs via symmetric and asymmetric modes of cell segregation, resulting in more populated mature OLs at the bottom layer of the cortex. These data suggest that fourth postnatal week, corresponding to the early critical period of ocular dominance plasticity, is a developmentally sensitive period for OPC state changes. Overall, the visual loss promoted undifferentiation at the early period, but later increased the formation of mature OLs via a change in the mode of cell type symmetry at the bottom layer of mouse V1.
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Affiliation(s)
- Hyeryun Shin
- Department of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo, Japan
| | - Hideki Derek Kawai
- Department of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo, Japan
- Department of Biosciences, Graduate School of Science and Engineering, Soka University, Hachioji, Tokyo, Japan
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32
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Inactivation of Hedgehog signal transduction in adult astrocytes results in region-specific blood-brain barrier defects. Proc Natl Acad Sci U S A 2021; 118:2017779118. [PMID: 34417306 DOI: 10.1073/pnas.2017779118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
In this study, we use molecular genetic approaches to clarify the role of the Hedgehog (Hh) pathway in regulating the blood-brain/spinal cord barrier (BBB) in the adult mouse central nervous system (CNS). Our work confirms and extends prior studies to demonstrate that astrocytes are the predominant cell type in the adult CNS that transduce Hh signaling, revealed by the expression of Gli1, a target gene of the canonical pathway that is activated in cells receiving Hh, and other key pathway transduction components. Gli1+ (Hh-responsive) astrocytes are distributed in specific regions of the CNS parenchyma, including layers 4/5/6 of the neocortex, hypothalamus, thalamus, and spinal cord, among others. Notably, although BBB properties in endothelial cells are normally regulated by both paracellular and transcellular mechanisms, conditional inactivation of Hh signaling in astrocytes results in transient, region-specific BBB defects that affect transcytosis but not paracellular diffusion. These findings stand in contrast to prior studies that implicated astrocytes as a source of Sonic hedgehog that limited extravasation via both mechanisms [J. I. Alvarez et al., Science 334, 1727-1731 (2011)]. Furthermore, using three distinct Cre driver lines as well as pharmacological approaches to inactivate Hh-pathway transduction globally in CNS astrocytes, we find that these specific BBB defects are only detected in the rostral hypothalamus and spinal cord but not the cortex or other regions where Gli1+ astrocytes are found. Together, our data show that Gli1+ Hh-responsive astrocytes have regionally distinct molecular and functional properties and that the pathway is required to maintain BBB properties in specific regions of the adult mammalian CNS.
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33
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Decoding the Roles of Astrocytes and Hedgehog Signaling in Medulloblastoma. ACTA ACUST UNITED AC 2021; 28:3058-3070. [PMID: 34436033 PMCID: PMC8395412 DOI: 10.3390/curroncol28040267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/01/2021] [Accepted: 08/04/2021] [Indexed: 01/09/2023]
Abstract
The molecular evolution of medulloblastoma is more complex than previously imagined, as emerging evidence suggests that multiple interactions between the tumor cells and components of the tumor microenvironment (TME) are important for tumor promotion and progression. The identification of several molecular networks within the TME, which interact with tumoral cells, has provided new clues to understand the tumorigenic roles of many TME components as well as potential therapeutic targets. In this review, we discuss the most recent studies regarding the roles of astrocytes in supporting sonic hedgehog (SHH) subgroup medulloblastoma (MB) and provide an overview of MB progression through SHH expression and signal transduction mechanisms into the complex tumor microenvironment. In addition, we highlight the associations between tumor and stromal cells as possible prognostic markers that could be targeted with new therapeutic strategies.
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New Tricks for an Old (Hedge)Hog: Sonic Hedgehog Regulation of Astrocyte Function. Cells 2021; 10:cells10061353. [PMID: 34070740 PMCID: PMC8228508 DOI: 10.3390/cells10061353] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 01/12/2023] Open
Abstract
The Sonic hedgehog (Shh) molecular signaling pathway is well established as a key regulator of neurodevelopment. It regulates diverse cellular behaviors, and its functions vary with respect to cell type, region, and developmental stage, reflecting the incredible pleiotropy of this molecular signaling pathway. Although it is best understood for its roles in development, Shh signaling persists into adulthood and is emerging as an important regulator of astrocyte function. Astrocytes play central roles in a broad array of nervous system functions, including synapse formation and function as well as coordination and orchestration of CNS inflammatory responses in pathological states. Neurons are the source of Shh in the adult, suggesting that Shh signaling mediates neuron-astrocyte communication, a novel role for this multifaceted pathway. Multiple roles for Shh signaling in astrocytes are increasingly being identified, including regulation of astrocyte identity, modulation of synaptic organization, and limitation of inflammation. This review discusses these novel roles for Shh signaling in regulating diverse astrocyte functions in the healthy brain and in pathology.
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Ho EK, Stearns T. Hedgehog signaling and the primary cilium: implications for spatial and temporal constraints on signaling. Development 2021; 148:dev195552. [PMID: 33914866 PMCID: PMC8126410 DOI: 10.1242/dev.195552] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mechanisms of vertebrate Hedgehog signaling are linked to the biology of the primary cilium, an antenna-like organelle that projects from the surface of most vertebrate cell types. Although the advantages of restricting signal transduction to cilia are often noted, the constraints imposed are less frequently considered, and yet they are central to how Hedgehog signaling operates in developing tissues. In this Review, we synthesize current understanding of Hedgehog signal transduction, ligand secretion and transport, and cilia dynamics to explore the temporal and spatial constraints imposed by the primary cilium on Hedgehog signaling in vivo.
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Affiliation(s)
- Emily K. Ho
- Department of Developmental Biology, Stanford School of Medicine, Stanford, CA 94305, USA
| | - Tim Stearns
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Department of Genetics, Stanford School of Medicine, Stanford, CA 94305, USA
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Hedgehog Signaling Modulates Glial Proteostasis and Lifespan. Cell Rep 2021; 30:2627-2643.e5. [PMID: 32101741 DOI: 10.1016/j.celrep.2020.02.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 11/11/2019] [Accepted: 01/31/2020] [Indexed: 12/18/2022] Open
Abstract
The conserved Hedgehog signaling pathway has well-established roles in development. However, its function during adulthood remains largely unknown. Here, we investigated whether the Hedgehog signaling pathway is active during adult life in Drosophila melanogaster, and we uncovered a protective function for Hedgehog signaling in coordinating correct proteostasis in glial cells. Adult-specific depletion of Hedgehog reduces lifespan, locomotor activity, and dopaminergic neuron integrity. Conversely, increased expression of Hedgehog extends lifespan and improves fitness. Moreover, Hedgehog pathway activation in glia rescues the lifespan and age-associated defects of hedgehog mutants. The Hedgehog pathway regulates downstream chaperones, whose overexpression in glial cells was sufficient to rescue the shortened lifespan and proteostasis defects of hedgehog mutants. Finally, we demonstrate the protective ability of Hedgehog signaling in a Drosophila Alzheimer's disease model expressing human amyloid beta in the glia. Overall, we propose that Hedgehog signaling is requisite for lifespan determination and correct proteostasis in glial cells.
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SRF Is Required for Maintenance of Astrocytes in Non-Reactive State in the Mammalian Brain. eNeuro 2021; 8:ENEURO.0447-19.2020. [PMID: 33441399 PMCID: PMC7877468 DOI: 10.1523/eneuro.0447-19.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/24/2020] [Accepted: 12/24/2020] [Indexed: 11/21/2022] Open
Abstract
Astrocytes play several critical roles in the normal functioning of the mammalian brain, including ion homeostasis, synapse formation, and synaptic plasticity. Following injury and infection or in the setting of neurodegeneration, astrocytes become hypertrophic and reactive, a process termed astrogliosis. Although acute reactive gliosis is beneficial in limiting further tissue damage, chronic gliosis becomes detrimental for neuronal recovery and regeneration. Several extracellular factors have been identified that generate reactive astrocytes; however, very little is known about the cell-autonomous transcriptional mechanisms that regulate the maintenance of astrocytes in the normal non-reactive state. Here, we show that conditional deletion of the stimulus-dependent transcription factor, serum response factor (SRF) in astrocytes (SrfGFAPCKO) results in astrogliosis marked by hypertrophic morphology and increased expression of GFAP, vimentin, and nestin. These reactive astrocytes were not restricted to any specific brain region and were seen in both white and gray matter in the entire brain. This astrogliosis persisted throughout adulthood concomitant with microglial activation. Importantly, the Srf mutant mouse brain did not exhibit any cell death or blood brain barrier (BBB) deficits suggesting that apoptosis and leaky BBB are not the causes for the reactive phenotype. The mutant astrocytes expressed more A2 reactive astrocyte marker genes and the SrfGFAPCKO mice exhibited normal neuronal numbers indicating that SRF-deficient gliosis astrocytes are not neurotoxic. Together, our findings suggest that SRF plays a critical role in astrocytes to maintain them in a non-reactive state.
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Tirou L, Russo M, Faure H, Pellegrino G, Demongin C, Daynac M, Sharif A, Amosse J, Le Lay S, Denis R, Luquet S, Taouis M, Benomar Y, Ruat M. Sonic Hedgehog receptor Patched deficiency in astrocytes enhances glucose metabolism in mice. Mol Metab 2021; 47:101172. [PMID: 33513436 PMCID: PMC7893488 DOI: 10.1016/j.molmet.2021.101172] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/12/2021] [Accepted: 01/21/2021] [Indexed: 01/06/2023] Open
Abstract
Objective Astrocytes are glial cells proposed as the main Sonic hedgehog (Shh)-responsive cells in the adult brain. Their roles in mediating Shh functions are still poorly understood. In the hypothalamus, astrocytes support neuronal circuits implicated in the regulation of energy metabolism. In this study, we investigated the impact of genetic activation of Shh signaling on hypothalamic astrocytes and characterized its effects on energy metabolism. Methods We analyzed the distribution of gene transcripts of the Shh pathway (Ptc, Gli1, Gli2, and Gli3) in astrocytes using single molecule fluorescence in situ hybridization combined with immunohistofluorescence of Shh peptides by Western blotting in the adult mouse hypothalamus. Based on the metabolic phenotype, we characterized Glast-CreERT2-YFP-Ptc−/− (YFP-Ptc−/−) mice and their controls over time and under a high-fat diet (HFD) to investigate the potential effects of conditional astrocytic deletion of the Shh receptor Patched (Ptc) on metabolic efficiency, insulin sensitivity, and systemic glucose metabolism. Molecular and biochemical assays were used to analyze the alteration of key pathways modulating energy metabolism, insulin sensitivity, glucose uptake, and inflammation. Primary astrocyte cultures were used to evaluate a potential role of Shh signaling in astrocytic glucose uptake. Results Shh peptides were the highest in the hypothalamic extracts of adult mice and a large population of hypothalamic astrocytes expressed Ptc and Gli1-3 mRNAs. Characterization of Shh signaling after conditional Ptc deletion in the YFP-Ptc−/− mice revealed heterogeneity in hypothalamic astrocyte populations. Interestingly, activation of Shh signaling in Glast+ astrocytes enhanced insulin responsiveness as evidenced by glucose and insulin tolerance tests. This effect was maintained over time and associated with lower blood insulin levels and also observed under a HFD. The YFP-Ptc−/− mice exhibited a lean phenotype with the absence of body weight gain and a marked reduction of white and brown adipose tissues accompanied by increased whole-body fatty acid oxidation. In contrast, food intake, locomotor activity, and body temperature were not altered. At the cellular level, Ptc deletion did not affect glucose uptake in primary astrocyte cultures. In the hypothalamus, activation of the astrocytic Shh pathway was associated with the upregulation of transcripts coding for the insulin receptor and liver kinase B1 (LKB1) after 4 weeks and the glucose transporter GLUT-4 after 32 weeks. Conclusions Here, we define hypothalamic Shh action on astrocytes as a novel master regulator of energy metabolism. In the hypothalamus, astrocytic Shh signaling could be critically involved in preventing both aging- and obesity-related metabolic disorders. Astrocytes exhibit differences in regulating the hedgehog signaling pathway. Deletion of Ptc in Glast+ cells prevents body weight gain and insulin resistance. Deletion of Ptc in Glast+ cells increases β oxidation. Central hedgehog signaling participates in the regulation of whole-body metabolism.
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Affiliation(s)
- Linda Tirou
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, F-91198, Gif-sur-Yvette, France
| | - Mariagiovanna Russo
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, F-91198, Gif-sur-Yvette, France
| | - Helene Faure
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, F-91198, Gif-sur-Yvette, France
| | - Giuliana Pellegrino
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, F-91198, Gif-sur-Yvette, France
| | - Clement Demongin
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, F-91198, Gif-sur-Yvette, France
| | - Mathieu Daynac
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, F-91198, Gif-sur-Yvette, France
| | - Ariane Sharif
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog (JPARC) - Lille Neurosciences & Cognition, F-59000, Lille, France
| | - Jeremy Amosse
- Univ. Angers SFR ICAT, F-49100, Angers, France; IRSET Laboratory, Inserm, UMR, 1085, Rennes, France
| | - Soazig Le Lay
- Univ. Angers SFR ICAT, F-49100, Angers, France; Univ. Nantes, CNRS, Inserm, Thorax Institut, F-44000, Nantes, France
| | - Raphaël Denis
- Univ. Paris, BFA, UMR 8251, CNRS, F-75013, Paris, France
| | - Serge Luquet
- Univ. Paris, BFA, UMR 8251, CNRS, F-75013, Paris, France
| | - Mohammed Taouis
- CNRS, Paris-Saclay University, UMR 9197, Neuroscience Paris-Saclay Institute, Molecular Neuroendocrinology of Food Intake, Orsay, France
| | - Yacir Benomar
- CNRS, Paris-Saclay University, UMR 9197, Neuroscience Paris-Saclay Institute, Molecular Neuroendocrinology of Food Intake, Orsay, France
| | - Martial Ruat
- CNRS, Paris-Saclay University, UMR-9197, Neuroscience Paris-Saclay Institute, F-91198, Gif-sur-Yvette, France.
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Hill SA, Fu M, Garcia ADR. Sonic hedgehog signaling in astrocytes. Cell Mol Life Sci 2021; 78:1393-1403. [PMID: 33079226 PMCID: PMC7904711 DOI: 10.1007/s00018-020-03668-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 09/02/2020] [Accepted: 10/05/2020] [Indexed: 01/12/2023]
Abstract
Astrocytes are complex cells that perform a broad array of essential functions in the healthy and injured nervous system. The recognition that these cells are integral components of various processes, including synapse formation, modulation of synaptic activity, and response to injury, underscores the need to identify the molecular signaling programs orchestrating these diverse functional properties. Emerging studies have identified the Sonic hedgehog (Shh) signaling pathway as an essential regulator of the molecular identity and functional properties of astrocytes. Well established as a powerful regulator of diverse neurodevelopmental processes in the embryonic nervous system, its functional significance in astrocytes is only beginning to be revealed. Notably, Shh signaling is active only in discrete subpopulations of astrocytes distributed throughout the brain, a feature that has potential to yield novel insights into functional specialization of astrocytes. Here, we discuss Shh signaling and emerging data that point to essential roles for this pleiotropic signaling pathway in regulating various functional properties of astrocytes in the healthy and injured brain.
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Affiliation(s)
- Steven A Hill
- Department of Biology, Drexel University, Philadelphia, PA, 19104, USA
| | - Marissa Fu
- Department of Biology, Drexel University, Philadelphia, PA, 19104, USA
| | - A Denise R Garcia
- Department of Biology, Drexel University, Philadelphia, PA, 19104, USA.
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, 19129, USA.
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La Sala G, Di Pietro C, Matteoni R, Bolasco G, Marazziti D, Tocchini-Valentini GP. Gpr37l1/prosaposin receptor regulates Ptch1 trafficking, Shh production, and cell proliferation in cerebellar primary astrocytes. J Neurosci Res 2020; 99:1064-1083. [PMID: 33350496 DOI: 10.1002/jnr.24775] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 11/30/2020] [Indexed: 02/24/2024]
Abstract
Mammalian cerebellar astrocytes critically regulate the differentiation and maturation of neuronal Purkinje cells and granule precursors. The G protein-coupled receptor 37-like 1 (Gpr37l1) is expressed by Bergmann astrocytes and interacts with patched 1 (Ptch1) at peri-ciliary membranes. Cerebellar primary astrocyte cultures from wild-type and Gpr37l1 null mutant mouse pups were established and studied. Primary cilia were produced by cultures of both genotypes, as well as Ptch1 and smoothened (Smo) components of the sonic hedgehog (Shh) mitogenic pathway. Compared to wild-type cells, Gpr37l1-/- astrocytes displayed striking increases in proliferative activity, Ptch1 protein expression and internalization, intracellular cholesterol content, ciliary localization of Smo, as well as a marked production of active Shh. Similar effects were reproduced by treating wild-type astrocytes with a putative prosaptide ligand of Gpr37l1. These findings indicate that Gpr37l1-Ptch1 interactions specifically regulate Ptch1 internalization and trafficking, with consequent stimulation of Shh production and activation of proliferative signaling.
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Affiliation(s)
- Gina La Sala
- Institute of Biochemistry and Cell Biology, Italian National Research Council (CNR), Monterotondo Scalo, Rome, Italy
| | - Chiara Di Pietro
- Institute of Biochemistry and Cell Biology, Italian National Research Council (CNR), Monterotondo Scalo, Rome, Italy
| | - Rafaele Matteoni
- Institute of Biochemistry and Cell Biology, Italian National Research Council (CNR), Monterotondo Scalo, Rome, Italy
| | - Giulia Bolasco
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Monterotondo Scalo, Rome, Italy
| | - Daniela Marazziti
- Institute of Biochemistry and Cell Biology, Italian National Research Council (CNR), Monterotondo Scalo, Rome, Italy
| | - Glauco P Tocchini-Valentini
- Institute of Biochemistry and Cell Biology, Italian National Research Council (CNR), Monterotondo Scalo, Rome, Italy
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Radecki DZ, Messling HM, Haggerty-Skeans JR, Bhamidipati SK, Clawson ED, Overman CA, Thatcher MM, Salzer JL, Samanta J. Relative Levels of Gli1 and Gli2 Determine the Response of Ventral Neural Stem Cells to Demyelination. Stem Cell Reports 2020; 15:1047-1055. [PMID: 33125874 PMCID: PMC7664046 DOI: 10.1016/j.stemcr.2020.10.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 10/02/2020] [Accepted: 10/02/2020] [Indexed: 02/06/2023] Open
Abstract
Enhancing repair of myelin is an important therapeutic goal in many neurological disorders characterized by demyelination. In the healthy adult brain, ventral neural stem cells (vNSCs) in the subventricular zone, marked by GLI1 expression, do not generate oligodendrocytes. However, in response to demyelination, their progeny are recruited to lesions where they differentiate into oligodendrocytes and ablation of GLI1 further enhances remyelination. GLI1 and GLI2 are closely related transcriptional activators but the role of GLI2 in remyelination by vNSCs is not clear. Here, we show that genetic ablation of Gli1 in vNSCs increases GLI2 expression and combined loss of both transcription factors decreases the recruitment and differentiation of their progeny in demyelinated lesions. These results indicate that GLI1 and GLI2 have distinct, non-redundant functions in vNSCs and their relative levels play an essential role in the response to demyelination. Loss of Gli1 increases GLI2 expression in SVZ neural stem cells upon demyelination Loss of Gli1 and Gli2 inhibits recruitment of neural stem cell progeny to the lesion Loss of Gli1 and Gli2 decreases their differentiation into oligodendrocytes
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Affiliation(s)
- Daniel Z Radecki
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Heather M Messling
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - James R Haggerty-Skeans
- Department of Neuroscience and Physiology, Neuroscience Institute, NYU Langone Medical Center, New York, NY 10016, USA
| | - Sai Krishna Bhamidipati
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Elizabeth D Clawson
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Christian A Overman
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Madison M Thatcher
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - James L Salzer
- Department of Neuroscience and Physiology, Neuroscience Institute, NYU Langone Medical Center, New York, NY 10016, USA
| | - Jayshree Samanta
- Stem Cell and Regenerative Medicine Center, Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA.
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Ming X, Dupree JL, Gallo V, Chew LJ. Sox17 Promotes Oligodendrocyte Regeneration by Dual Modulation of Hedgehog and Wnt Signaling. iScience 2020; 23:101592. [PMID: 33083751 PMCID: PMC7553347 DOI: 10.1016/j.isci.2020.101592] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 08/29/2020] [Accepted: 09/16/2020] [Indexed: 12/14/2022] Open
Abstract
Signaling pathways that promote oligodendrocyte development improve oligodendrocyte regeneration and myelin recovery from demyelinating pathologies. Sox factors critically control myelin gene expression and oligodendroglial fate, but little is known about signaling events underlying Sox-mediated oligodendroglial regeneration. In this study of the SoxF member Sox17, we demonstrate that Sox17-induced oligodendrocyte regeneration in adult myelin lesions occurs by suppressing lesion-induced Wnt/beta-catenin signaling which is inhibitory to oligodendrocyte regeneration and by increasing Sonic Hedgehog/Smoothened/Gli2 activity. Hedgehog signaling through Smoothened critically supports adult oligodendroglial viability and is an upstream regulator of beta-catenin. Gli2 ablation in adult oligodendrocyte progenitor cells indicates that Gli2 regulates beta-catenin differentially in wild-type and Sox17-overexpressing white matter. Myelin lesions in Sox17-deficient mice show beta-catenin hyperactivation, regenerative failure, and loss of oligodendrogenesis, despite exogenous Hedgehog stimulation. These studies indicate the benefit of Sox17 signaling targets to enhance oligodendrocyte regeneration after demyelination injury by modulating both Hedgehog and Wnt/beta-catenin signaling.
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Affiliation(s)
- Xiaotian Ming
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, Washington DC 20010, USA
| | - Jeffrey L Dupree
- Department Anatomy and Neurobiol, Virginia Commonwealth Univ, Richmond, VA, USA.,Research Service, Hunter Holmes McGuire VA Medical Center, Richmond, VA 23249, USA
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, Washington DC 20010, USA
| | - Li-Jin Chew
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, Washington DC 20010, USA
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Gupta V, Gupta I, Park J, Bram Y, Schwartz RE. Hedgehog Signaling Demarcates a Niche of Fibrogenic Peribiliary Mesenchymal Cells. Gastroenterology 2020; 159:624-638.e9. [PMID: 32289375 PMCID: PMC8204800 DOI: 10.1053/j.gastro.2020.03.075] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 03/18/2020] [Accepted: 03/30/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS In response to tissue injury, stromal cells secrete extracellular matrix (ECM) components that remodel the tissue and lead to fibrosis. Parenchymal stellate cells are the primary contributors to fibrosis in models of hepatocellular and cholestatic injury. The liver comprises different, heterogenous compartments; stromal cells within those compartments might have unique identities and regional functions. The portal tract contains the bile duct, which is surrounded by stromal cells often called portal fibroblasts. We investigated the contributions of these cells to hepatic injury. METHODS We performed studies with Gli1:CreERT2;Rosa26:lox-STOP-lox-tdTomato mice. Mice underwent bile duct ligation or were fed 3,5-diethoxycarbonyl-1,4-dihydrocollidine to induce cholestatic injury or were given carbon tetrachloride to induce liver fibrosis. Liver tissues were collected and analyzed by histology and immunofluorescence, and mesenchymal cells were isolated. We performed lineage tracing experiments to determine the fates of peribiliary mesenchymal cells (PMCs) that surround the bile duct after cholestatic and hepatocellular injury. We used cell sorting combined with RNA sequencing to isolate stellate cells and PMCs, and we identified determinants of cell identity within each population. Liver tissues were obtained from patients with primary sclerosing cholangitis, alcoholic liver disease, or nonalcoholic steatohepatitis or individuals without disease and were analyzed by quantitative reverse transcription polymerase chain reaction. RESULTS Gli1 was a marker of mesenchymal cells that surround the biliary tree but not epithelial cells of the canals of Hering. Lineage-traced Gli1+ PMCs proliferated and acquired a myofibroblast phenotype after cholestatic injury; Gli1+ PMCs were found only surrounding the main duct of a portal tract but not the epithelial cells of the ductular reaction, which were instead encased by stellate cells. Compared with stellate cells, Gli1+ PMCs expressed a different subset of genes, including genes that are markers of active hedgehog signaling, Osr1 (encodes a transcription factor), and ECM-related genes. Loss of hedgehog signaling reduced expression of Osr1 and PMC-specific ECM genes. Liver tissues from patients with liver disease had increased expression of genes that define PMC identity compared with control liver tissues. CONCLUSIONS In lineage-tracing studies of mice, we found that Gli1+ PMCs are a subset of stromal cells characterized by active hedgehog signaling that proliferate, acquire a myofibroblast phenotype, and surround the biliary tree in response to cholestatic injury.
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Affiliation(s)
- Vikas Gupta
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, New York.
| | - Ishaan Gupta
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi – 110 016, India
| | - Jiwoon Park
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, NY 10021, USA
| | - Yaron Bram
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, NY 10021, USA
| | - Robert E. Schwartz
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, NY 10021, USA
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Astroglial contribution to tau-dependent neurodegeneration. Biochem J 2020; 476:3493-3504. [PMID: 31774919 DOI: 10.1042/bcj20190506] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 11/07/2019] [Accepted: 11/08/2019] [Indexed: 01/31/2023]
Abstract
Astrocytes, by maintaining an optimal environment for neuronal function, play a critical role in proper function of mammalian nervous system. They regulate synaptic transmission and plasticity and protect neurons against toxic insults. Astrocytes and neurons interact actively via glutamine-glutamate cycle (GGC) that supports neuronal metabolic demands and neurotransmission. GGC deficiency may be involved in different diseases of the brain, where impaired astrocytic control of glutamate homeostasis contributes to neuronal dysfunction. This includes tau-dependent neurodegeneration, where astrocytes lose key molecules involved in regulation of glutamate/glutamine homeostasis, neuronal survival and synaptogenesis. Astrocytic dysfunction in tauopathy appears to precede neurodegeneration and overt tau neuropathology such as phosphorylation, aggregation and formation of neurofibrillary tangles. In this review, we summarize recent studies demonstrating that activation of astrocytes is strictly associated with neurodegenerative processes including those involved in tau related pathology. We propose that astrocytic dysfunction, by disrupting the proper neuron-glia signalling early in the disease, significantly contributes to tauopathy pathogenesis.
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45
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Garcia PE, Adoumie M, Kim EC, Zhang Y, Scales MK, El-Tawil YS, Shaikh AZ, Wen HJ, Bednar F, Allen BL, Wellik DM, Crawford HC, Pasca di Magliano M. Differential Contribution of Pancreatic Fibroblast Subsets to the Pancreatic Cancer Stroma. Cell Mol Gastroenterol Hepatol 2020; 10:581-599. [PMID: 32454112 PMCID: PMC7399194 DOI: 10.1016/j.jcmgh.2020.05.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 05/14/2020] [Accepted: 05/14/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Although the healthy pancreas consists mostly of epithelial cells, pancreatic cancer and the precursor lesions known as pancreatic intraepithelial neoplasia, are characterized by an extensive accumulation of fibroinflammatory stroma that includes a substantial and heterogeneous fibroblast population. The cellular origin of fibroblasts within the stroma has not been determined. Here, we show that the Gli1 and Hoxb6 markers label distinct fibroblast populations in the healthy mouse pancreas. We then set out to determine whether these distinct fibroblast populations expanded during carcinogenesis. METHODS We developed genetically engineered models using a dual-recombinase approach that allowed us to induce pancreatic cancer formation through codon-optimized Flp recombinase-driven epithelial recombination of Kirsten rat sarcoma viral oncogene homolog while labeling Gli1+ or Hoxb6+ fibroblasts in an inducible manner. By using these models, we lineage-traced these 2 fibroblast populations during the process of carcinogenesis. RESULTS Although in the healthy pancreas Gli1+ fibroblasts and Hoxb6+ fibroblasts are present in similar numbers, they contribute differently to the stroma in carcinogenesis. Namely, Gli1+ fibroblasts expand dramatically, whereas Hoxb6+ cells do not. CONCLUSIONS Fibroblasts present in the healthy pancreas expand during carcinogenesis, but with a different prevalence for different subtypes. Here, we compared Gli1+ and Hoxb6+ fibroblasts and found only Gli1+ expanded to contribute to the stroma during pancreatic carcinogenesis.
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Affiliation(s)
| | | | | | | | | | | | | | - Hui-Ju Wen
- Department of Molecular and Integrative Physiology
| | | | - Ben L. Allen
- Rogel Cancer Center,Department of Cell and Developmental Biology
| | - Deneen M. Wellik
- Department of Cellular and Regenerative Biology, University of Wisconsin–Madison, Madison, Wisconsin
| | - Howard C. Crawford
- Rogel Cancer Center,Department of Molecular and Integrative Physiology,Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Marina Pasca di Magliano
- Department of Surgery,Rogel Cancer Center,Department of Cell and Developmental Biology,Correspondence Address correspondence to: Marina Pasca di Magliano, PhD, Department of Surgery, University of Michigan, 1500 East Medical Center Drive, 4304 Cancer Center, SPC 5936, Ann Arbor, Michigan 48109; fax: (734) 615-7424.
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46
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Pestana F, Edwards-Faret G, Belgard TG, Martirosyan A, Holt MG. No Longer Underappreciated: The Emerging Concept of Astrocyte Heterogeneity in Neuroscience. Brain Sci 2020; 10:brainsci10030168. [PMID: 32183137 PMCID: PMC7139801 DOI: 10.3390/brainsci10030168] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/02/2020] [Accepted: 03/05/2020] [Indexed: 12/18/2022] Open
Abstract
Astrocytes are ubiquitous in the central nervous system (CNS). These cells possess thousands of individual processes, which extend out into the neuropil, interacting with neurons, other glia and blood vessels. Paralleling the wide diversity of their interactions, astrocytes have been reported to play key roles in supporting CNS structure, metabolism, blood-brain-barrier formation and control of vascular blood flow, axon guidance, synapse formation and modulation of synaptic transmission. Traditionally, astrocytes have been studied as a homogenous group of cells. However, recent studies have uncovered a surprising degree of heterogeneity in their development and function, in both the healthy and diseased brain. A better understanding of astrocyte heterogeneity is urgently needed to understand normal brain function, as well as the role of astrocytes in response to injury and disease.
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Affiliation(s)
- Francisco Pestana
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, 3000 Leuven, Belgium;
| | - Gabriela Edwards-Faret
- Laboratory of Neuronal Wiring, VIB-KU Leuven Center for Brain and Disease Research, 3000 Leuven, Belgium;
- Life & Medical Sciences (LIMES) Institute, Faculty of Mathematics and Natural Sciences, University of Bonn, 53115 Bonn, Germany
| | | | - Araks Martirosyan
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, 3000 Leuven, Belgium;
- Correspondence: (A.M.); (M.G.H.); Tel.: +32-16-37-31-27 (M.G.H.)
| | - Matthew G. Holt
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, 3000 Leuven, Belgium;
- Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
- Correspondence: (A.M.); (M.G.H.); Tel.: +32-16-37-31-27 (M.G.H.)
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Batiuk MY, Martirosyan A, Wahis J, de Vin F, Marneffe C, Kusserow C, Koeppen J, Viana JF, Oliveira JF, Voet T, Ponting CP, Belgard TG, Holt MG. Identification of region-specific astrocyte subtypes at single cell resolution. Nat Commun 2020; 11:1220. [PMID: 32139688 PMCID: PMC7058027 DOI: 10.1038/s41467-019-14198-8] [Citation(s) in RCA: 392] [Impact Index Per Article: 98.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 12/17/2019] [Indexed: 01/26/2023] Open
Abstract
Astrocytes, a major cell type found throughout the central nervous system, have general roles in the modulation of synapse formation and synaptic transmission, blood-brain barrier formation, and regulation of blood flow, as well as metabolic support of other brain resident cells. Crucially, emerging evidence shows specific adaptations and astrocyte-encoded functions in regions, such as the spinal cord and cerebellum. To investigate the true extent of astrocyte molecular diversity across forebrain regions, we used single-cell RNA sequencing. Our analysis identifies five transcriptomically distinct astrocyte subtypes in adult mouse cortex and hippocampus. Validation of our data in situ reveals distinct spatial positioning of defined subtypes, reflecting the distribution of morphologically and physiologically distinct astrocyte populations. Our findings are evidence for specialized astrocyte subtypes between and within brain regions. The data are available through an online database (https://holt-sc.glialab.org/), providing a resource on which to base explorations of local astrocyte diversity and function in the brain.
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Affiliation(s)
- Mykhailo Y Batiuk
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium
| | - Araks Martirosyan
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium
| | - Jérôme Wahis
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium
| | - Filip de Vin
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium
| | - Catherine Marneffe
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium
| | - Carola Kusserow
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium
| | - Jordan Koeppen
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium
| | - João Filipe Viana
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal
- ICVS/3Bs - PT Government Associate Laboratory, Braga, Portugal
| | - João Filipe Oliveira
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal
- ICVS/3Bs - PT Government Associate Laboratory, Braga, Portugal
- IPCA-EST-2Ai, Polytechnic Institute of Cávado and Ave, Applied Artificial Intelligence Laboratory, IPCA Campus, Barcelos, Portugal
| | - Thierry Voet
- Sanger Institute-EBI Single-Cell Genomics Centre, Wellcome Trust Sanger Institute, Hinxton, UK
- KU Leuven Department of Human Genetics, Leuven, Belgium
| | - Chris P Ponting
- Sanger Institute-EBI Single-Cell Genomics Centre, Wellcome Trust Sanger Institute, Hinxton, UK
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - T Grant Belgard
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- The Bioinformatics CRO, Niceville, Florida, 32578, USA
| | - Matthew G Holt
- Laboratory of Glia Biology, VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium.
- Laboratory of Glia Biology, KU Leuven Department of Neuroscience, Leuven, Belgium.
- Leuven Brain Institute, KU Leuven, Leuven, Belgium.
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48
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Tirou L, Russo M, Faure H, Pellegrino G, Sharif A, Ruat M. C9C5 positive mature oligodendrocytes are a source of Sonic Hedgehog in the mouse brain. PLoS One 2020; 15:e0229362. [PMID: 32078657 PMCID: PMC7032736 DOI: 10.1371/journal.pone.0229362] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/04/2020] [Indexed: 12/12/2022] Open
Abstract
In the mature rodent brain, Sonic Hedgehog (Shh) signaling regulates stem and progenitor cell maintenance, neuronal and glial circuitry and brain repair. However, the sources and distribution of Shh mediating these effects are still poorly characterized. Here, we report in the adult mouse brain, a broad expression pattern of Shh recognized by the specific monoclonal C9C5 antibody in a subset (11–12%) of CC1+ mature oligodendrocytes that do not express carbonic anhydrase II. These cells express also Olig2 and Sox10, two oligodendrocyte lineage-specific markers, but not PDGFRα, a marker of oligodendrocyte progenitors. In agreement with oligodendroglial cells being a source of Shh in the adult mouse brain, we identify Shh transcripts by single molecule fluorescent in situ hybridization in a subset of cells expressing Olig2 and Sox10 mRNAs. These findings also reveal that Shh expression is more extensive than originally reported. The Shh-C9C5-associated signal labels the oligodendroglial cell body and decorates by intense puncta the processes. C9C5+ cells are distributed in a grid-like manner. They constitute small units that could deliver locally Shh to its receptor Patched expressed in GFAP+ and S100β+ astrocytes, and in HuC/D+ neurons as shown in PtcLacZ/+ reporter mice. Postnatally, C9C5 immunoreactivity overlaps the myelination peak that occurs between P10 and P20 and is down regulated during ageing. Thus, our data suggest that C9C5+CC1+ oligodendroglial cells are a source of Shh in the mouse postnatal brain.
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Affiliation(s)
- Linda Tirou
- UMR-9197, Neuroscience Paris-Saclay Institute, CNRS, Paris Saclay University, Gif-sur-Yvette, France
| | - Mariagiovanna Russo
- UMR-9197, Neuroscience Paris-Saclay Institute, CNRS, Paris Saclay University, Gif-sur-Yvette, France
| | - Helene Faure
- UMR-9197, Neuroscience Paris-Saclay Institute, CNRS, Paris Saclay University, Gif-sur-Yvette, France
| | - Giuliana Pellegrino
- UMR-9197, Neuroscience Paris-Saclay Institute, CNRS, Paris Saclay University, Gif-sur-Yvette, France
| | | | - Martial Ruat
- UMR-9197, Neuroscience Paris-Saclay Institute, CNRS, Paris Saclay University, Gif-sur-Yvette, France
- * E-mail:
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Palpagama TH, Waldvogel HJ, Faull RLM, Kwakowsky A. The Role of Microglia and Astrocytes in Huntington's Disease. Front Mol Neurosci 2019; 12:258. [PMID: 31708741 PMCID: PMC6824292 DOI: 10.3389/fnmol.2019.00258] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 10/10/2019] [Indexed: 12/21/2022] Open
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disease. HD patients present with movement disorders, behavioral and psychiatric symptoms and cognitive decline. This review summarizes the contribution of microglia and astrocytes to HD pathophysiology. Neuroinflammation in the HD brain is characterized by a reactive morphology in these glial cells. Microglia and astrocytes are critical in regulating neuronal activity and maintaining an optimal milieu for neuronal function. Previous studies provide evidence that activated microglia and reactive astrocytes contribute to HD pathology through transcriptional activation of pro-inflammatory genes to perpetuate a chronic inflammatory state. Reactive astrocytes also display functional changes in glutamate and ion homeostasis and energy metabolism. Astrocytic and microglial changes may further contribute to the neuronal death observed with the progression of HD. Importantly, the degree to which these neuroinflammatory changes are detrimental to neurons and contribute to the progression of HD pathology is not well understood. Furthermore, recent observations provide compelling evidence that activated microglia and astrocytes exert a variety of beneficial functions that are essential for limiting tissue damage and preserving neuronal function in the HD brain. Therefore, a better understanding of the neuroinflammatory environment in the brain in HD may lead to the development of targeted and innovative therapeutic opportunities.
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Affiliation(s)
- Thulani H Palpagama
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Henry J Waldvogel
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Richard L M Faull
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Andrea Kwakowsky
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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50
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The Elegance of Sonic Hedgehog: Emerging Novel Functions for a Classic Morphogen. J Neurosci 2019; 38:9338-9345. [PMID: 30381425 DOI: 10.1523/jneurosci.1662-18.2018] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/27/2018] [Accepted: 09/28/2018] [Indexed: 12/12/2022] Open
Abstract
Sonic Hedgehog (SHH) signaling has been most widely known for its role in specifying region and cell-type identity during embryonic morphogenesis. This mini-review accompanies a 2018 SFN mini-symposium that addresses an emerging body of research focused on understanding the diverse roles for Shh signaling in a wide range of contexts in neurodevelopment and, more recently, in the mature CNS. Such research shows that Shh affects the function of brain circuits, including the production and maintenance of diverse cell types and the establishment of wiring specificity. Here, we review these novel and unexpected functions and the unanswered questions regarding the role of SHH and its signaling pathway members in these cases.
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