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Krzeski JC, Judson MC, Philpot BD. Neuronal UBE3A substrates hold therapeutic potential for Angelman syndrome. Curr Opin Neurobiol 2024; 88:102899. [PMID: 39126903 DOI: 10.1016/j.conb.2024.102899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 06/22/2024] [Accepted: 07/16/2024] [Indexed: 08/12/2024]
Abstract
Emerging therapies for Angelman syndrome, a severe neurodevelopmental disorder, are focused on restoring UBE3A gene expression in the brain. Further therapeutic opportunities may arise from a better understanding of how UBE3A gene products-both long and short isoforms of the ubiquitin ligase E3A (UBE3A)-function in neurons. Great strides have been made recently toward identifying ubiquitin substrates of UBE3A in vitro and in heterologous expression systems. From this work, a particularly close relationship between UBE3A and subunits of the 19S regulatory particle of the proteasome has become evident. We propose that further research cognizant of isoform-specific UBE3A functional roles will be instrumental in elucidating key UBE3A/substrate relationships within distinct neuronal compartments, lending to the discovery of novel therapeutic targets and valuable clinical biomarkers for the treatment of Angelman syndrome.
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Affiliation(s)
- Joseph C Krzeski
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, NC, USA; Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Matthew C Judson
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, NC, USA; Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Benjamin D Philpot
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, NC, USA; Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA; Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, USA.
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2
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p27, The Cell Cycle and Alzheimer´s Disease. Int J Mol Sci 2022; 23:ijms23031211. [PMID: 35163135 PMCID: PMC8835212 DOI: 10.3390/ijms23031211] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 12/29/2022] Open
Abstract
The cell cycle consists of successive events that lead to the generation of new cells. The cell cycle is regulated by different cyclins, cyclin-dependent kinases (CDKs) and their inhibitors, such as p27Kip1. At the nuclear level, p27Kip1 has the ability to control the evolution of different phases of the cell cycle and oppose cell cycle progression by binding to CDKs. In the cytoplasm, diverse functions have been described for p27Kip1, including microtubule remodeling, axonal transport and phagocytosis. In Alzheimer’s disease (AD), alterations to cycle events and a purported increase in neurogenesis have been described in the early disease process before significant pathological changes could be detected. However, most neurons cannot progress to complete their cell division and undergo apoptotic cell death. Increased levels of both the p27Kip1 levels and phosphorylation status have been described in AD. Increased levels of Aβ42, tau hyperphosphorylation or even altered insulin signals could lead to alterations in p27Kip1 post-transcriptional modifications, causing a disbalance between the levels and functions of p27Kip1 in the cytoplasm and nucleus, thus inducing an aberrant cell cycle re-entry and alteration of extra cell cycle functions. Further studies are needed to completely understand the role of p27Kip1 in AD and the therapeutic opportunities associated with the modulation of this target.
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3
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Mayweather BA, Buchanan SM, Rubin LL. GDF11 expressed in the adult brain negatively regulates hippocampal neurogenesis. Mol Brain 2021; 14:134. [PMID: 34488822 PMCID: PMC8422669 DOI: 10.1186/s13041-021-00845-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 08/24/2021] [Indexed: 11/20/2022] Open
Abstract
Growth differentiation factor 11 (GDF11) is a transforming factor-β superfamily member that functions as a negative regulator of neurogenesis during embryonic development. However, when recombinant GDF11 (rGDF11) is administered systemically in aged mice, it promotes neurogenesis, the opposite of its role during development. The goal of the present study was to reconcile this apparent discrepancy by performing the first detailed investigation into the expression of endogenous GDF11 in the adult brain and its effects on neurogenesis. Using quantitative histological analysis, we observed that Gdf11 is most highly expressed in adult neurogenic niches and non-neurogenic regions within the hippocampus, choroid plexus, thalamus, habenula, and cerebellum. To investigate the role of endogenous GDF11 during adult hippocampal neurogenesis, we generated a tamoxifen inducible mouse that allowed us to reduce GDF11 levels. Depletion of Gdf11 during adulthood increased proliferation of neural progenitors and decreased the number of newborn neurons in the hippocampus, suggesting that endogenous GDF11 remains a negative regulator of hippocampal neurogenesis in adult mice. These findings further support the idea that circulating systemic GDF11 and endogenously expressed GDF11 in the adult brain have different target cells or mechanisms of action. Our data describe a role for GDF11-dependent signaling in adult neurogenesis that has implications for how GDF11 may be used to treat CNS disease.
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Affiliation(s)
- Brittany A Mayweather
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA.,Graduate Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, USA
| | - Sean M Buchanan
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Lee L Rubin
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA. .,Harvard Stem Cell Institute, Sherman Fairchild Bldg, 7 Divinity Ave., Cambridge, MA, 02138, USA.
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4
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Mayerl S, Heuer H, Ffrench-Constant C. Hippocampal Neurogenesis Requires Cell-Autonomous Thyroid Hormone Signaling. Stem Cell Reports 2020; 14:845-860. [PMID: 32302557 PMCID: PMC7220957 DOI: 10.1016/j.stemcr.2020.03.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 03/14/2020] [Accepted: 03/17/2020] [Indexed: 02/07/2023] Open
Abstract
Adult hippocampal neurogenesis is strongly dependent on thyroid hormone (TH). Whether TH signaling regulates this process in a cell-autonomous or non-autonomous manner remains unknown. To answer this question, we used global and conditional knockouts of the TH transporter monocarboxylate transporter 8 (MCT8), having first used FACS and immunohistochemistry to demonstrate that MCT8 is the only TH transporter expressed on neuroblasts and adult slice cultures to confirm a necessary role for MCT8 in neurogenesis. Both mice with a global deletion or an adult neural stem cell-specific deletion of MCT8 showed decreased expression of the cell-cycle inhibitor P27KIP1, reduced differentiation of neuroblasts, and impaired generation of new granule cell neurons, with global knockout mice also showing enhanced neuroblast proliferation. Together, our results reveal a cell-autonomous role for TH signaling in adult hippocampal neurogenesis alongside non-cell-autonomous effects on cell proliferation earlier in the lineage.
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Affiliation(s)
- Steffen Mayerl
- MRC Centre for Regenerative Medicine, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK.
| | - Heike Heuer
- University of Duisburg-Essen, University Hospital Essen, Department of Endocrinology, Essen, Germany
| | - Charles Ffrench-Constant
- MRC Centre for Regenerative Medicine, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
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5
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Littlejohn EL, Scott D, Saatman KE. Insulin-like growth factor-1 overexpression increases long-term survival of posttrauma-born hippocampal neurons while inhibiting ectopic migration following traumatic brain injury. Acta Neuropathol Commun 2020; 8:46. [PMID: 32276671 PMCID: PMC7147070 DOI: 10.1186/s40478-020-00925-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/29/2020] [Indexed: 01/29/2023] Open
Abstract
Cellular damage associated with traumatic brain injury (TBI) manifests in motor and cognitive dysfunction following injury. Experimental models of TBI reveal cell death in the granule cell layer (GCL) of the hippocampal dentate gyrus acutely after injury. Adult-born neurons residing in the neurogenic niche of the GCL, the subgranular zone, are particularly vulnerable. Injury-induced proliferation of neural progenitors in the subgranular zone supports recovery of the immature neuron population, but their development and localization may be altered, potentially affecting long-term survival. Here we show that increasing hippocampal levels of insulin-like growth factor-1 (IGF1) is sufficient to promote end-stage maturity of posttrauma-born neurons and improve cognition following TBI. Mice with conditional overexpression of astrocyte-specific IGF1 and wild-type mice received controlled cortical impact or sham injury and bromo-2'-deoxyuridine injections for 7d after injury to label proliferating cells. IGF1 overexpression increased the number of GCL neurons born acutely after trauma that survived 6 weeks to maturity (NeuN+BrdU+), and enhanced their outward migration into the GCL while significantly reducing the proportion localized ectopically to the hilus and molecular layer. IGF1 selectively affected neurons, without increasing the persistence of posttrauma-proliferated glia in the dentate gyrus. IGF1 overexpressing animals performed better during radial arm water maze reversal testing, a neurogenesis-dependent cognitive test. These findings demonstrate the ability of IGF1 to promote the long-term survival and appropriate localization of granule neurons born acutely after a TBI, and suggest these new neurons contribute to improved cognitive function.
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Affiliation(s)
- Erica L. Littlejohn
- grid.266539.d0000 0004 1936 8438Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky, B473 Biomedical & Biological Sciences Research Building (BBSRB), 741 South Limestone St, Lexington, KY 40536-0509 USA ,grid.267309.90000 0001 0629 5880Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229-3901 USA
| | - Danielle Scott
- grid.266539.d0000 0004 1936 8438Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky, B473 Biomedical & Biological Sciences Research Building (BBSRB), 741 South Limestone St, Lexington, KY 40536-0509 USA
| | - Kathryn E. Saatman
- grid.266539.d0000 0004 1936 8438Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky, B473 Biomedical & Biological Sciences Research Building (BBSRB), 741 South Limestone St, Lexington, KY 40536-0509 USA ,grid.266539.d0000 0004 1936 8438Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536 USA
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6
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Hutton CP, Lemon JA, Sakic B, Rollo CD, Boreham DR, Fahnestock M, Wojtowicz JM, Becker S. Early Intervention with a Multi-Ingredient Dietary Supplement Improves Mood and Spatial Memory in a Triple Transgenic Mouse Model of Alzheimer's Disease. J Alzheimers Dis 2019; 64:835-857. [PMID: 29914019 DOI: 10.3233/jad-170921] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The increasing global burden of Alzheimer's disease (AD) and failure of conventional treatments to stop neurodegeneration necessitates an alternative approach. Evidence of inflammation, mitochondrial dysfunction, and oxidative stress prior to the accumulation of amyloid-β in the prodromal stage of AD (mild cognitive impairment; MCI) suggests that early interventions which counteract these features, such as dietary supplements, may ameliorate the onset of MCI-like behavioral symptoms. We administered a polyphenol-containing multiple ingredient dietary supplement (MDS), or vehicle, to both sexes of triple transgenic (3xTg-AD) mice and wildtype mice for 2 months from 2-4 months of age. We hypothesized that the MDS would preserve spatial learning, which is known to be impaired in untreated 3xTg-AD mice by 4 months of age. Behavioral phenotyping of animals was done at 1-2 and 3-4 months of age using a comprehensive battery of tests. As previously reported in males, both sexes of 3xTg-AD mice exhibited increased anxiety-like behavior at 1-2 months of age, prior to deficits in learning and memory, which did not appear until 3-4 months of age. The MDS did not reduce this anxiety or prevent impairments in novel object recognition (both sexes) or on the water maze probe trial (females only). Strikingly, the MDS specifically prevented 3xTg-AD mice (both sexes) from developing impairments (exhibited by untreated 3xTg-AD controls) in working memory and spatial learning. The MDS also increased sucrose preference, an indicator of hedonic tone. These data show that the MDS can prevent some, but not all, psychopathology in an AD model.
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Affiliation(s)
- Craig P Hutton
- Department of Psychology, Neuroscience & Behavior, McMaster University, Hamilton, ON, Canada
| | - Jennifer A Lemon
- Department of Biology, McMaster University, Hamilton, ON, Canada
| | - Boris Sakic
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON, Canada
| | - C David Rollo
- Department of Biology, McMaster University, Hamilton, ON, Canada
| | | | - Margaret Fahnestock
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON, Canada
| | | | - Suzanna Becker
- Department of Psychology, Neuroscience & Behavior, McMaster University, Hamilton, ON, Canada
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7
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Urbach A, Witte OW. Divide or Commit - Revisiting the Role of Cell Cycle Regulators in Adult Hippocampal Neurogenesis. Front Cell Dev Biol 2019; 7:55. [PMID: 31069222 PMCID: PMC6491688 DOI: 10.3389/fcell.2019.00055] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 03/28/2019] [Indexed: 12/21/2022] Open
Abstract
The adult dentate gyrus continuously generates new neurons that endow the brain with increased plasticity, helping to cope with changing environmental and cognitive demands. The process leading to the birth of new neurons spans several precursor stages and is the result of a coordinated series of fate decisions, which are tightly controlled by extrinsic signals. Many of these signals act through modulation of cell cycle (CC) components, not only to drive proliferation, but also for linage commitment and differentiation. In this review, we provide a comprehensive overview on key CC components and regulators, with emphasis on G1 phase, and analyze their specific functions in precursor cells of the adult hippocampus. We explore their role for balancing quiescence versus self-renewal, which is essential to maintain a lifelong pool of neural stem cells while producing new neurons “on demand.” Finally, we discuss available evidence and controversies on the impact of CC/G1 length on proliferation versus differentiation decisions.
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Affiliation(s)
- Anja Urbach
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Otto W Witte
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
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8
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Rampioni Vinciguerra GL, Citron F, Segatto I, Belletti B, Vecchione A, Baldassarre G. p27kip1 at the crossroad between actin and microtubule dynamics. Cell Div 2019; 14:2. [PMID: 30976290 PMCID: PMC6442415 DOI: 10.1186/s13008-019-0045-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 03/19/2019] [Indexed: 12/11/2022] Open
Abstract
The p27kip1 protein, mainly known as a negative regulator of cell proliferation, has also been involved in the control of other cellular processes, including the regulation of cytoskeleton dynamics. Notably, these two functions involve distinct protein domains, residing in the N- and C-terminal halves, respectively. In the last two decades, p27kip1 has been reported to interact with microtubule and acto-myosin cytoskeletons, both in direct and indirect ways, overall drawing a picture in which several factors play their role either in synergy or in contrast one with another. As a result, the role of p27kip1 in cytoskeleton dynamics has been implicated in cell migration, both in physiologic and in neoplastic contexts, modulating cytokinesis, lipid raft trafficking, and neuronal development. Recently, two distinct papers have further reported a central role for p27kip1 in the control of microtubule stability and post-translational modifications, dissecting the interaction between p27kip1 and α-tubulin-acetyl-transferase (α-TAT), an enzyme involved in the stability of microtubules, and protein-regulator of cytokinesis 1 (PRC1), a nuclear regulator of the central spindle during mitosis. In light of these recent evidences, we will comment on the role of p27kip1 on cytoskeleton regulation and its implication for cancer progression.
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Affiliation(s)
- Gian Luca Rampioni Vinciguerra
- 1Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, National Cancer Institute, 33081 Aviano, Italy.,2Faculty of Medicine and Psychology, Department of Clinical and Molecular Medicine, University of Rome "Sapienza", Santo Andrea Hospital, 00189 Rome, Italy
| | - Francesca Citron
- 1Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, National Cancer Institute, 33081 Aviano, Italy
| | - Ilenia Segatto
- 1Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, National Cancer Institute, 33081 Aviano, Italy
| | - Barbara Belletti
- 1Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, National Cancer Institute, 33081 Aviano, Italy
| | - Andrea Vecchione
- 2Faculty of Medicine and Psychology, Department of Clinical and Molecular Medicine, University of Rome "Sapienza", Santo Andrea Hospital, 00189 Rome, Italy
| | - Gustavo Baldassarre
- 1Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, National Cancer Institute, 33081 Aviano, Italy
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9
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Caron N, Genin EC, Marlier Q, Verteneuil S, Beukelaers P, Morel L, Hu MG, Hinds PW, Nguyen L, Vandenbosch R, Malgrange B. Proliferation of hippocampal progenitors relies on p27-dependent regulation of Cdk6 kinase activity. Cell Mol Life Sci 2018; 75:3817-3827. [PMID: 29728713 PMCID: PMC11105564 DOI: 10.1007/s00018-018-2832-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 03/02/2018] [Accepted: 05/02/2018] [Indexed: 10/17/2022]
Abstract
Neural stem cells give rise to granule dentate neurons throughout life in the hippocampus. Upon activation, these stem cells generate fast proliferating progenitors that complete several rounds of divisions before differentiating into neurons. Although the mechanisms regulating the activation of stem cells have been intensively studied, little attention has been given so far to the intrinsic machinery allowing the expansion of the progenitor pool. The cell cycle protein Cdk6 positively regulates the proliferation of hippocampal progenitors, but the mechanism involved remains elusive. Whereas Cdk6 functions primarily as a cell cycle kinase, it can also act as transcriptional regulator in cancer cells and hematopoietic stem cells. Using mouse genetics, we show here that the function of Cdk6 in hippocampal neurogenesis relies specifically on its kinase activity. The present study also reveals a specific regulatory mechanism for Cdk6 in hippocampal progenitors. In contrast to the classical model of the cell cycle, we observe that the Cip/Kip family member p27, rather than the Ink4 family, negatively regulates Cdk6 in the adult hippocampus. Altogether, our data uncover a unique, cell type-specific regulatory mechanism controlling the expansion of hippocampal progenitors, where Cdk6 kinase activity is modulated by p27.
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Affiliation(s)
- Nicolas Caron
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences, Quartier Hôpital, University of Liège, Avenue Hippocrate 15, B36 +1, 4000, Liège, Belgium
| | - Emmanuelle C Genin
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences, Quartier Hôpital, University of Liège, Avenue Hippocrate 15, B36 +1, 4000, Liège, Belgium
| | - Quentin Marlier
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences, Quartier Hôpital, University of Liège, Avenue Hippocrate 15, B36 +1, 4000, Liège, Belgium
| | - Sébastien Verteneuil
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences, Quartier Hôpital, University of Liège, Avenue Hippocrate 15, B36 +1, 4000, Liège, Belgium
| | - Pierre Beukelaers
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences, Quartier Hôpital, University of Liège, Avenue Hippocrate 15, B36 +1, 4000, Liège, Belgium
| | - Laurence Morel
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL, USA
| | - Miaofen G Hu
- Molecular Oncology Research Institute, Tufts Medical Center, 75 Kneeland Street, Boston, MA, USA
| | - Philip W Hinds
- Molecular Oncology Research Institute, Tufts Medical Center, 75 Kneeland Street, Boston, MA, USA
- Department of Developmental, Molecular, and Chemical Biology, Tufts University School of Medicine, Boston, MA, USA
| | - Laurent Nguyen
- Molecular Regulation of Neurogenesis, GIGA-Neurosciences, University of Liège, Liège, Belgium
| | - Renaud Vandenbosch
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences, Quartier Hôpital, University of Liège, Avenue Hippocrate 15, B36 +1, 4000, Liège, Belgium
| | - Brigitte Malgrange
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences, Quartier Hôpital, University of Liège, Avenue Hippocrate 15, B36 +1, 4000, Liège, Belgium.
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10
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Depression and adult neurogenesis: Positive effects of the antidepressant fluoxetine and of physical exercise. Brain Res Bull 2018; 143:181-193. [PMID: 30236533 DOI: 10.1016/j.brainresbull.2018.09.002] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/03/2018] [Accepted: 09/11/2018] [Indexed: 12/11/2022]
Abstract
Of wide interest for health is the relation existing between depression, a very common psychological illness, accompanied by anxiety and reduced ability to concentrate, and adult neurogenesis. We will focus on two neurogenic stimuli, fluoxetine and physical exercise, both endowed with the ability to activate adult neurogenesis in the dentate gyrus of the hippocampus, known to be required for learning and memory, and both able to counteract depression. Fluoxetine belongs to the class of selective serotonin reuptake inhibitor (SSRI) antidepressants, which represent the most used pharmacological therapy; physical exercise has also been shown to effectively counteract depression symptoms in rodents as well as in humans. While there is evidence that the antidepressant effect of fluoxetine requires its pro-neurogenic action, exerted by promoting proliferation, differentiation and survival of progenitor cells of the hippocampus, on the other hand fluoxetine exerts also neurogenesis-independent antidepressant effects by influencing the plasticity of the new neurons generated. Similarly, the antidepressant action of running also correlates with an increase of hippocampal neurogenesis and plasticity, although the gene pathways involved are only partially coincident with those of fluoxetine, such as those involved in serotonin metabolism and synapse formation. We further discuss how extra-neurogenic actions are also suggested by the fact that, unlike running, fluoxetine is unable to stimulate neurogenesis during aging, but still displays antidepressant effects. Moreover, in specific conditions, fluoxetine or running activate not only progenitor but also stem cells, which normally are not stimulated; this fact reveals how stem cells have a long-term, hidden ability to self-renew and, more generally, that neurogenesis is subject to complex controls that may play a role in depression, such as the type of neurogenic stimulus or the state of the local niche. Finally, we discuss how fluoxetine or running are effective in counteracting depression originated from stress or neurodegenerative diseases.
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11
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Bernas SN, Leiter O, Walker TL, Kempermann G. Isolation, Culture and Differentiation of Adult Hippocampal Precursor Cells. Bio Protoc 2017; 7:e2603. [PMID: 34595279 DOI: 10.21769/bioprotoc.2603] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 10/10/2017] [Accepted: 10/12/2017] [Indexed: 11/02/2022] Open
Abstract
There are two neurogenic niches in the adult mammalian brain: the subventricular zone of the lateral ventricle and the subgranular zone of the hippocampal dentate gyrus. Cells from these areas can be isolated and maintained in vitro, using two different culture systems to assess their potential regarding proliferation and differentiation in a reductionist model. While the neurosphere assay is primarily performed to directly study the proliferative and differentiation potential of cells in individual brains, the monolayer culture allows single cell analysis in a rather homogeneous cell population. Here, we describe the isolation, culturing methods and differentiation of neural precursor cells in both systems.
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Affiliation(s)
- Stefanie N Bernas
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Odette Leiter
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Tara L Walker
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Gerd Kempermann
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
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