1
|
Advani D, Kumar P. Uncovering Cell Cycle Dysregulations and Associated Mechanisms in Cancer and Neurodegenerative Disorders: A Glimpse of Hope for Repurposed Drugs. Mol Neurobiol 2024:10.1007/s12035-024-04130-7. [PMID: 38532240 DOI: 10.1007/s12035-024-04130-7] [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: 12/25/2023] [Accepted: 03/19/2024] [Indexed: 03/28/2024]
Abstract
The cell cycle is the sequence of events orchestrated by a complex network of cell cycle proteins. Unlike normal cells, mature neurons subsist in a quiescent state of the cell cycle, and aberrant cell cycle activation triggers neuronal death accompanied by neurodegeneration. The periodicity of cell cycle events is choreographed by various mechanisms, including DNA damage repair, oxidative stress, neurotrophin activity, and ubiquitin-mediated degradation. Given the relevance of cell cycle processes in cancer and neurodegeneration, this review delineates the overlapping cell cycle events, signaling pathways, and mechanisms associated with cell cycle aberrations in cancer and the major neurodegenerative disorders. We suggest that dysregulation of some common fundamental signaling processes triggers anomalous cell cycle activation in cancer cells and neurons. We discussed the possible use of cell cycle inhibitors for neurodegenerative disorders and described the associated challenges. We propose that a greater understanding of the common mechanisms driving cell cycle aberrations in cancer and neurodegenerative disorders will open a new avenue for the development of repurposed drugs.
Collapse
Affiliation(s)
- Dia Advani
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly Delhi College of Engineering), Shahbad Daulatpur, Bawana Road, New Delhi, Delhi, 110042, India
| | - Pravir Kumar
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly Delhi College of Engineering), Shahbad Daulatpur, Bawana Road, New Delhi, Delhi, 110042, India.
| |
Collapse
|
2
|
Younger DS. Paraneoplastic motor disorders. HANDBOOK OF CLINICAL NEUROLOGY 2023; 196:231-250. [PMID: 37620071 DOI: 10.1016/b978-0-323-98817-9.00018-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
Paraneoplastic neurological disorders (PNDs) are heterogeneous clinicopathologic syndromes that occur throughout the neuraxis resulting from damage to organs or tissues remote from the site of a malignant neoplasm or its metastases. The discordance between severe neurological disability and even an indolent malignancy suggests an underlying neuroimmunologic host immune response that inflicts nervous tissue damage while inhibiting malignant tumor growth. Motor system involvement, like other symptoms and signs, is associated with focal or diffuse involvement of the brain, spinal cord, peripheral nerve, neuromuscular junction or muscle, alone or in combination due to an underlying neuroimmune and neuroinflammatory process targeting neural-specific antigens. Unrecognized and therefore untreated, PNDs are often lethal making early detection and aggressive treatment of paramount importance. While the combination of clinical symptoms and signs, and analysis of detailed body and neuroimaging, clinical neurophysiology and electrodiagnostic studies, and tumor and nervous system tissue biopsies are all vitally important, the certain diagnosis of a PND rests with the discovery of a corresponding neural-specific paraneoplastic autoantibody in the blood and/or spinal cerebrospinal fluid.
Collapse
Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
| |
Collapse
|
3
|
Iqbal NJ, Schwartz GJ, Zhao H, Zhu L, Chua S. Cyclin-dependent kinase 4/6 inhibitors require an arcuate-to-paraventricular hypothalamus melanocortin circuit to treat diet-induced obesity. Am J Physiol Endocrinol Metab 2021; 320:E467-E474. [PMID: 33356996 PMCID: PMC7988782 DOI: 10.1152/ajpendo.00386.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The arcuate nucleus (ARC) of the hypothalamus comprises two antagonistic neuron populations critical for energy balance, namely, the anorexigenic pro-opiomelanocortin (POMC) and the orexigenic agouti-related peptide (AgRP) neurons that act as agonists and antagonists, respectively, for neurons expressing the type IV melanocortin receptor (MC4R) (Andermann ML and Lowell BB. Neuron 95: 757-778, 2017). MC4R activation increases energy expenditure and decreases food intake during positive energy balance states to prevent diet-induced obesity (DIO). Work from our group identified aberrant neuronal cell cycle events both as a novel biomarker and druggable target in the ARC for the treatment of DIO, demonstrating pharmacological restoration of retinoblastoma protein function in the ARC using cyclin-dependent kinase 4/6 (CDK4/6) inhibitors could treat DIO in mice by increasing lipid oxidation to selectively decrease fat mass. However, the role of CDK4/6 inhibitors on food intake was not examined. Four-week-old Mc4r-loxTB mice were continuously administered high-fat diet (60% kcal fat). At 8 wk of age, animals were administered 60 mg/kg abemaciclib orally or a saline control and monitored every 2 wk for fat mass changes by MRI. At 11 wk of age, all animals were injected bilaterally in the paraventricular hypothalamus with AAV8 serotype virus expressing a Cre-mCherry and monitored for another 5 wk. Restoration of Mc4r expression in the paraventricular hypothalamic nucleus (PVN/PVH) reduced food intake in hyperphagic obese mice when given CDK4/6 inhibitor therapy. The reduced food intake was responsible for reduced fat mass in mice treated with abemaciclib. These results indicate that targeting POMC neurons could be an effective strategy in treating diet-related obesity.NEW & NOTEWORTHY We have defined some of the necessary components to prevent high-fat diet-induced obesity at the molecular and cellular level. Within POMC neurons, the retinoblastoma protein must remain active and prevented from phosphoinactivation by cyclin-dependent kinases. The downstream neurons within the PVH must also properly express MC4R for the circuit to appropriately regulate feeding behavior.
Collapse
Affiliation(s)
- Niloy Jafar Iqbal
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Gary J Schwartz
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York
| | - Hongling Zhao
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Liang Zhu
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Streamson Chua
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York
| |
Collapse
|
4
|
Barrett T, Stangis KA, Saito T, Saido T, Park KH. Neuronal Cell Cycle Re-Entry Enhances Neuropathological Features in AppNLF Knock-In Mice. J Alzheimers Dis 2021; 82:1683-1702. [PMID: 34219712 PMCID: PMC8461670 DOI: 10.3233/jad-210091] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2021] [Indexed: 01/02/2023]
Abstract
BACKGROUND Aberrant cell cycle re-entry is a well-documented process occurring early in Alzheimer's disease (AD). This is an early feature of the disease and may contribute to disease pathogenesis. OBJECTIVE To assess the effect of forced neuronal cell cycle re-entry in mice expressing humanized Aβ, we crossed our neuronal cell cycle re-entry mouse model with AppNLF knock-in (KI) mice. METHODS Our neuronal cell cycle re-entry (NCCR) mouse model is bitransgenic mice heterozygous for both Camk2a-tTA and TRE-SV40T. The NCCR mice were crossed with AppNLF KI mice to generate NCCR-AppNLF animals. Using this tet-off system, we triggered NCCR in our animals via neuronal expression of SV40T starting at 1 month of age. The animals were examined at the following time points: 9, 12, and 18 months of age. Various neuropathological features in our mice were evaluated by image analysis and stereology on brain sections stained using either immunofluorescence or immunohistochemistry. RESULTS We show that neuronal cell cycle re-entry in humanized Aβ plaque producing AppNLF KI mice results in the development of additional AD-related pathologies, namely, pathological tau, neuroinflammation, brain leukocyte infiltration, DNA damage response, and neurodegeneration. CONCLUSION Our findings show that neuronal cell cycle re-entry enhances AD-related neuropathological features in AppNLF mice and highlight our unique AD mouse model for studying the pathogenic role of aberrant cell cycle re-entry in AD.
Collapse
Affiliation(s)
- Tomás Barrett
- Neuroscience Program, Central Michigan University, Mount Pleasant, MI, USA
| | | | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, Japan
| | - Takaomi Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Kevin H.J. Park
- Neuroscience Program, Central Michigan University, Mount Pleasant, MI, USA
- Department of Psychology, Central Michigan University, Mount Pleasant, MI, USA
- Biochemistry, Cellular & Molecular Biology Graduate Program, Central Michigan University, Mount Pleasant, MI, USA
- Michigan Alzheimer’s Disease Research Center, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
5
|
Zhang Y, Song X, Herrup K. Context-Dependent Functions of E2F1: Cell Cycle, Cell Death, and DNA Damage Repair in Cortical Neurons. Mol Neurobiol 2020; 57:2377-2390. [PMID: 32062842 DOI: 10.1007/s12035-020-01887-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 01/29/2020] [Indexed: 01/17/2023]
Abstract
DNA damage has been reported to induce cell cycle-related neuronal death. This is significant as aberrant cell cycle re-entry of mature, post-mitotic neurons contributes to neurodegeneration. In this study, we investigate how DNA damage elicited by exposure to the topoisomerase I inhibitor camptothecin (CPT) leads to cycle-related death of cultured cortical neurons and examine the function of E2F1 in this process. CPT treatment induced cell cycle initiation of cortical neurons and elevated the expression of certain cell cycle components (e.g., cyclin D1, CDK4, E2F1) but failed to drive S phase entry or DNA synthesis. The arrest in the cell cycle is explained by the elevated expression of the CDK inhibitor p21Cip1. Though its level was increased after CPT treatment, E2F1 did not drive treated neurons into the G1-S phase transition. E2F1 overexpression led to cell cycle activation and acute neuronal apoptosis without detectable entry of the neurons into S phase. ChIPseq analysis demonstrated that E2F1 predominantly occupies positions on or near the promoters of cell cycle related genes. Instead, in CPT-treated neurons, E2F1 preferentially regulated DNA repair related genes. Our study reveals that the functions of E2F1 in postmitotic neurons are context-dependent and offers novel insights into the role of E2F1 in DNA damage induced cycle-related neuronal death.
Collapse
Affiliation(s)
- Yang Zhang
- Division of Life Science and the State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Xuan Song
- Division of Life Science and the State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Karl Herrup
- Division of Life Science and the State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
| |
Collapse
|
6
|
Abstract
Differentiated neurons can undergo cell cycle re-entry during pathological conditions, but it remains largely accepted that M-phase is prohibited in these cells. Here we show that primary neurons at post-synaptogenesis stages of development can enter M-phase. We induced cell cycle re-entry by overexpressing a truncated Cyclin E isoform fused to Cdk2. Cyclin E/Cdk2 expression elicits canonical cell cycle checkpoints, which arrest cell cycle progression and trigger apoptosis. As in mitotic cells, checkpoint abrogation enables cell cycle progression through S and G2-phases into M-phase. Although most neurons enter M-phase, only a small subset undergo cell division. Alternatively, neurons can exit M-phase without cell division and recover the axon initial segment, a structural determinant of neuronal viability. We conclude that neurons and mitotic cells share S, G2 and M-phase regulation.
Collapse
|
7
|
Miterko LN, White JJ, Lin T, Brown AM, O'Donovan KJ, Sillitoe RV. Persistent motor dysfunction despite homeostatic rescue of cerebellar morphogenesis in the Car8 waddles mutant mouse. Neural Dev 2019; 14:6. [PMID: 30867000 PMCID: PMC6417138 DOI: 10.1186/s13064-019-0130-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 02/20/2019] [Indexed: 12/19/2022] Open
Abstract
Background Purkinje cells play a central role in establishing the cerebellar circuit. Accordingly, disrupting Purkinje cell development impairs cerebellar morphogenesis and motor function. In the Car8wdl mouse model of hereditary ataxia, severe motor deficits arise despite the cerebellum overcoming initial defects in size and morphology. Methods To resolve how this compensation occurs, we asked how the loss of carbonic anhydrase 8 (CAR8), a regulator of IP3R1 Ca2+ signaling in Purkinje cells, alters cerebellar development in Car8wdl mice. Using a combination of histological, physiological, and behavioral analyses, we determined the extent to which the loss of CAR8 affects cerebellar anatomy, neuronal firing, and motor coordination during development. Results Our results reveal that granule cell proliferation is reduced in early postnatal mutants, although by the third postnatal week there is enhanced and prolonged proliferation, plus an upregulation of Sox2 expression in the inner EGL. Modified circuit patterning of Purkinje cells and Bergmann glia accompany these granule cell adjustments. We also find that although anatomy eventually normalizes, the abnormal activity of neurons and muscles persists. Conclusions Our data show that losing CAR8 only transiently restricts cerebellar growth, but permanently damages its function. These data support two current hypotheses about cerebellar development and disease: (1) Sox2 expression may be upregulated at sites of injury and contribute to the rescue of cerebellar structure and (2) transient delays to developmental processes may precede permanent motor dysfunction. Furthermore, we characterize waddles mutant mouse morphology and behavior during development and propose a Sox2-positive, cell-mediated role for rescue in a mouse model of human motor diseases. Electronic supplementary material The online version of this article (10.1186/s13064-019-0130-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Lauren N Miterko
- Department of Pathology and Immunology, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.,Program in Developmental Biology, Baylor College of Medicine, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Joshua J White
- Department of Pathology and Immunology, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.,Department of Neuroscience, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Tao Lin
- Department of Pathology and Immunology, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Amanda M Brown
- Department of Pathology and Immunology, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.,Department of Neuroscience, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Kevin J O'Donovan
- Department of Chemistry and Life Science, United States Military Academy, West Point, New York, 10996, USA.,Burke Neurological Institute, Weill Cornell Medicine, White Plains, 10605, USA
| | - Roy V Sillitoe
- Department of Pathology and Immunology, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA. .,Department of Neuroscience, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA. .,Program in Developmental Biology, Baylor College of Medicine, Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA. .,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.
| |
Collapse
|
8
|
Barrio-Alonso E, Hernández-Vivanco A, Walton CC, Perea G, Frade JM. Cell cycle reentry triggers hyperploidization and synaptic dysfunction followed by delayed cell death in differentiated cortical neurons. Sci Rep 2018; 8:14316. [PMID: 30254284 PMCID: PMC6156334 DOI: 10.1038/s41598-018-32708-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 09/14/2018] [Indexed: 11/09/2022] Open
Abstract
Cell cycle reentry followed by neuronal hyperploidy and synaptic failure are two early hallmarks of Alzheimer's disease (AD), however their functional connection remains unexplored. To address this question, we induced cell cycle reentry in cultured cortical neurons by expressing SV40 large T antigen. Cell cycle reentry was followed by hyperploidy in ~70% of cortical neurons, and led to progressive axon initial segment loss and reduced density of dendritic PSD-95 puncta, which correlated with diminished spike generation and reduced spontaneous synaptic activity. This manipulation also resulted in delayed cell death, as previously observed in AD-affected hyperploid neurons. Membrane depolarization by high extracellular potassium maintained PSD-95 puncta density and partially rescued both spontaneous synaptic activity and cell death, while spike generation remained blocked. This suggests that AD-associated hyperploid neurons can be sustained in vivo if integrated in active neuronal circuits whilst promoting synaptic dysfunction. Thus, cell cycle reentry might contribute to cognitive impairment in early stages of AD and neuronal death susceptibility at late stages.
Collapse
Affiliation(s)
- E Barrio-Alonso
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute (CSIC), Madrid, Spain
| | - A Hernández-Vivanco
- Department of Functional and Systems Neurobiology, Cajal Institute (CSIC), Madrid, Spain
| | - C C Walton
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute (CSIC), Madrid, Spain
| | - G Perea
- Department of Functional and Systems Neurobiology, Cajal Institute (CSIC), Madrid, Spain
| | - J M Frade
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute (CSIC), Madrid, Spain.
| |
Collapse
|
9
|
Iqbal NJ, Lu Z, Liu SM, Schwartz GJ, Chua S, Zhu L. Cyclin-dependent kinase 4 is a preclinical target for diet-induced obesity. JCI Insight 2018; 3:123000. [PMID: 30185666 PMCID: PMC6171799 DOI: 10.1172/jci.insight.123000] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 07/26/2018] [Indexed: 12/12/2022] Open
Abstract
When obesity is caused by consumption of a high-fat diet, the tumor suppressor pRb is phosphoinactivated in the neurons of the mediobasal hypothalamus, a brain area critical for energy-balance regulation. However, the functional relevance of pRb phosphoinactivation in the mediobasal hypothalamus to diet-induced obesity remains unknown. Here, we show that inhibiting pRb phosphorylation in the mediobasal hypothalamus can prevent and treat diet-induced obesity in mice. Expressing an unphosphorylable pRb nonselectively in the mediobasal hypothalamus or conditionally in anorexigenic POMC neurons inhibits diet-induced obesity. Intracerebroventricular delivery of US Food and Drug Administration–approved (FDA-approved) cyclin-dependent kinase 4 (CDK4) inhibitor abemaciclib inhibits pRb phosphorylation in the mediobasal hypothalamus and prevents diet-induced obesity. Oral administration of abemaciclib at doses approved for human use reduces fat mass in diet-induced obese mice by increasing lipid oxidation without significantly reducing lean mass. With analysis of recent literature identifying CDK4 as the most abundantly expressed neuronal CDK in the mediobasal hypothalamus, our work uncovers CDK4 as the major kinase for hypothalamic pRb phosphoinactivation and a highly effective central antiobesity target. As three CDK4/6 inhibitors have recently received FDA approval for life-long breast cancer therapy, our study provides a preclinical basis for their expedient repurposing for obesity management. Inhibiting pRb phosphorylation in the mediobasal hypothalamus can prevent and treat diet-induced obesity in mice.
Collapse
Affiliation(s)
| | - Zhonglei Lu
- Department of Developmental and Molecular Biology and
| | - Shun Mei Liu
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
| | - Gary J Schwartz
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
| | - Streamson Chua
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
| | - Liang Zhu
- Department of Developmental and Molecular Biology and.,Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
| |
Collapse
|
10
|
Bayin NS, Wojcinski A, Mourton A, Saito H, Suzuki N, Joyner AL. Age-dependent dormant resident progenitors are stimulated by injury to regenerate Purkinje neurons. eLife 2018; 7:39879. [PMID: 30091706 PMCID: PMC6115187 DOI: 10.7554/elife.39879] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 07/30/2018] [Indexed: 01/19/2023] Open
Abstract
Outside of the neurogenic niches of the brain, postmitotic neurons have not been found to undergo efficient regeneration. We demonstrate that mouse Purkinje cells (PCs), which are born at midgestation and are crucial for development and function of cerebellar circuits, are rapidly and fully regenerated following their ablation at birth. New PCs are produced from immature FOXP2+ Purkinje cell precursors (iPCs) that are able to enter the cell cycle and support normal cerebellum development. The number of iPCs and their regenerative capacity, however, diminish soon after birth and consequently PCs are poorly replenished when ablated at postnatal day five. Nevertheless, the PC-depleted cerebella reach a normal size by increasing cell size, but scaling of neuron types is disrupted and cerebellar function is impaired. Our findings provide a new paradigm in the field of neuron regeneration by identifying a population of immature neurons that buffers against perinatal brain injury in a stage-dependent process.
Collapse
Affiliation(s)
- N Sumru Bayin
- Developmental Biology Program, Sloan Kettering Institute, New York, United States
| | - Alexandre Wojcinski
- Developmental Biology Program, Sloan Kettering Institute, New York, United States
| | - Aurelien Mourton
- Developmental Biology Program, Sloan Kettering Institute, New York, United States
| | - Hiromitsu Saito
- Department of Animal Functional Genomics of Advanced Science Research Promotion Center, Organization for the Promotion of Regional Innovation, Mie University, Tsu, JAPAN
| | - Noboru Suzuki
- Department of Animal Functional Genomics of Advanced Science Research Promotion Center, Organization for the Promotion of Regional Innovation, Mie University, Tsu, JAPAN
| | - Alexandra L Joyner
- Developmental Biology Program, Sloan Kettering Institute, New York, United States.,Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, United States
| |
Collapse
|
11
|
Fichtl A, Büttner A, Hof PR, Schmitz C, Kiessling MC. Delineation of Subregions in the Early Postnatal Human Cerebellum for Design-Based Stereologic Studies. Front Neuroanat 2018; 11:134. [PMID: 29358908 PMCID: PMC5766680 DOI: 10.3389/fnana.2017.00134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 12/20/2017] [Indexed: 01/05/2023] Open
Abstract
Recent design-based stereologic studies have shown that the early postnatal (<1 year of age) human cerebellum is characterized by very high plasticity and may thus be very sensitive to external and internal influences during the first year of life. A potential weakness of these studies is that they were not separately performed on functionally relevant subregions of the cerebellum, as was the case in a few design-based stereologic studies on the adult human cerebellum. The aim of the present study was to assess whether it is possible to identify unequivocally the primary, superior posterior, horizontal, ansoparamedian, and posterolateral fissures in the early postnatal human cerebellum, based on which functionally relevant subregions could be delineated. This was tested in 20 human post mortem cerebellar halves from subjects aged between 1 day and 11 months by means of a combined macroscopic and microscopic approach. We found that the superior posterior, horizontal, and posterolateral fissures can be reliably identified on all of the specimens. However, reliable and reproducible identification of the primary and ansoparamedian fissures was not possible. Accordingly, it appears feasible to perform subregion-specific investigations in the early postnatal human cerebellum when the identification of subregions is restricted to crus I (bordered by the superior posterior and horizontal fissures) and the flocculus (bordered by the posterolateral fissure). As such, it is recommended to define the entire cerebellar cortex as the region of interest in design-based stereologic studies on the early postnatal human cerebellum to guarantee reproducibility of results.
Collapse
Affiliation(s)
- Anna Fichtl
- Chair of Neuroanatomy, Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Andreas Büttner
- Institute of Forensic Medicine, University of Rostock, Rostock, Germany
| | - Patrick R Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Christoph Schmitz
- Chair of Neuroanatomy, Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Maren C Kiessling
- Chair of Neuroanatomy, Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| |
Collapse
|
12
|
Oshikawa M, Okada K, Tabata H, Nagata KI, Ajioka I. Dnmt1-dependent Chk1 pathway suppression is protective against neuron division. Development 2017; 144:3303-3314. [PMID: 28928282 DOI: 10.1242/dev.154013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Accepted: 08/01/2017] [Indexed: 12/19/2022]
Abstract
Neuronal differentiation and cell-cycle exit are tightly coordinated, even in pathological situations. When pathological neurons re-enter the cell cycle and progress through the S phase, they undergo cell death instead of division. However, the mechanisms underlying mitotic resistance are mostly unknown. Here, we have found that acute inactivation of retinoblastoma (Rb) family proteins (Rb, p107 and p130) in mouse postmitotic neurons leads to cell death after S-phase progression. Checkpoint kinase 1 (Chk1) pathway activation during the S phase prevented the cell death, and allowed the division of cortical neurons that had undergone acute Rb family inactivation, oxygen-glucose deprivation (OGD) or in vivo hypoxia-ischemia. During neurogenesis, cortical neurons became protected from S-phase Chk1 pathway activation by the DNA methyltransferase Dnmt1, and underwent cell death after S-phase progression. Our results indicate that Chk1 pathway activation overrides mitotic safeguards and uncouples neuronal differentiation from mitotic resistance.
Collapse
Affiliation(s)
- Mio Oshikawa
- Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
| | - Kei Okada
- Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
| | - Hidenori Tabata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai Aichi 480-0392, Japan
| | - Koh-Ichi Nagata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai Aichi 480-0392, Japan
| | - Itsuki Ajioka
- Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan .,The Japan Science and Technology Agency (JST), Precursory Research for Embryonic Science and Technology (PRESTO), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|
13
|
Poncelet L, Garigliany M, Ando K, Franssen M, Desmecht D, Brion JP. Cell cycle S phase markers are expressed in cerebral neuron nuclei of cats infected by the Feline Panleukopenia Virus. Cell Cycle 2016; 15:3482-3489. [PMID: 27830988 DOI: 10.1080/15384101.2016.1249546] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The cell cycle-associated neuronal death hypothesis, which has been proposed as a common mechanism for most neurodegenerative diseases, is notably supported by evidencing cell cycle effectors in neurons. However, in naturally occurring nervous system diseases, these markers are not expressed in neuron nuclei but in cytoplasmic compartments. In other respects, the Feline Panleukopenia Virus (FPV) is able to complete its cycle in mature brain neurons in the feline species. As a parvovirus, the FPV is strictly dependent on its host cell reaching the cell cycle S phase to start its multiplication. In this retrospective study on the whole brain of 12 cats with naturally-occurring, FPV-associated cerebellar atrophy, VP2 capsid protein expression was detected by immunostaining not only in some brain neuronal nuclei but also in neuronal cytoplasm in 2 cats, suggesting that viral mRNA translation was still occurring. In these cats, double immunostainings demonstrated the expression of cell cycle S phase markers cyclin A, cdk2 and PCNA in neuronal nuclei. Parvoviruses are able to maintain their host cells in S phase by triggering the DNA damage response. S139 phospho H2A1, a key player in the cell cycle arrest, was detected in some neuronal nuclei, supporting that infected neurons were also blocked into the S phase. PCR studies did not support a co-infection with an adeno or herpes virus. ERK1/2 nuclear accumulation was observed in some neurons suggesting that the ERK signaling pathway might be involved as a mechanism driving these neurons far into the cell cycle.
Collapse
Affiliation(s)
- Luc Poncelet
- a Laboratory of Anatomy, Biomechanics and Organogenesis, Faculty of Medicine, Université Libre de Bruxelles , Brussels , Belgium.,b ULB Neuroscience Insitute (UNI) , Brussels , Belgium
| | - Mutien Garigliany
- c Morphology and Pathology, Faculty of Veterinary Medicine, University of Liège , Liège , Belgium
| | - Kunie Ando
- b ULB Neuroscience Insitute (UNI) , Brussels , Belgium.,d Laboratory of Histology, Neuroanatomy and Neuropathology, Faculty of Medicine, Université Libre de Bruxelles , Brussels , Belgium
| | - Mathieu Franssen
- c Morphology and Pathology, Faculty of Veterinary Medicine, University of Liège , Liège , Belgium
| | - Daniel Desmecht
- c Morphology and Pathology, Faculty of Veterinary Medicine, University of Liège , Liège , Belgium
| | - Jean-Pierre Brion
- b ULB Neuroscience Insitute (UNI) , Brussels , Belgium.,d Laboratory of Histology, Neuroanatomy and Neuropathology, Faculty of Medicine, Université Libre de Bruxelles , Brussels , Belgium
| |
Collapse
|
14
|
The hippocampal cyclin D1 expression is involved in postoperative cognitive dysfunction after sevoflurane exposure in aged mice. Life Sci 2016; 160:34-40. [DOI: 10.1016/j.lfs.2016.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 07/05/2016] [Accepted: 07/10/2016] [Indexed: 01/08/2023]
|
15
|
Aranda-Anzaldo A, Dent MAR. Why Cortical Neurons Cannot Divide, and Why Do They Usually Die in the Attempt? J Neurosci Res 2016; 95:921-929. [PMID: 27402311 DOI: 10.1002/jnr.23765] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/25/2016] [Accepted: 04/25/2016] [Indexed: 12/19/2022]
Abstract
Cortical neurons are prime examples of terminally differentiated, postmitotic cells. However, under experimental or pathological conditions, they can re-enter the cell cycle and replicate DNA but are unable to divide, dying by apoptosis or becoming either polyploid or aneuploid. Any cellular state that depends on the action of genes and their products can be reverted or bypassed by spontaneous or induced mutations, yet there are currently no reports of dividing cortical neurons. Thus, it seems unlikely that the remarkably stable postmitotic condition of cortical neurons depends on specific gene functions. This Review summarizes evidence that the postmitotic state of cortical neurons depends on the high stability of its underlying nuclear structure that results from an entropy-driven process aimed at dissipating the intrinsic structural stress present in chromosomal DNA in such a way that the structural stability of the neuronal nucleus becomes an insurmountable energy barrier for karyokinesis and mitosis. From this perspective, the integral properties of the nuclear higher order structure in neurons provide an explanation not only for why cortical neurons cannot divide but also for why they usually die if they happen to replicate their DNA. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Armando Aranda-Anzaldo
- Laboratorio de Biología Molecular y Neurociencias, Facultad de Medicina, Universidad Autónoma del Estado de México, Toluca, Estado México, México
| | - Myrna A R Dent
- Laboratorio de Biología Molecular y Neurociencias, Facultad de Medicina, Universidad Autónoma del Estado de México, Toluca, Estado México, México
| |
Collapse
|
16
|
Cortical neurons gradually attain a post-mitotic state. Cell Res 2016; 26:1033-47. [PMID: 27325298 DOI: 10.1038/cr.2016.76] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 02/26/2016] [Accepted: 04/13/2016] [Indexed: 12/21/2022] Open
Abstract
Once generated, neurons are thought to permanently exit the cell cycle and become irreversibly differentiated. However, neither the precise point at which this post-mitotic state is attained nor the extent of its irreversibility is clearly defined. Here we report that newly born neurons from the upper layers of the mouse cortex, despite initiating axon and dendrite elongation, continue to drive gene expression from the neural progenitor tubulin α1 promoter (Tα1p). These observations suggest an ambiguous post-mitotic neuronal state. Whole transcriptome analysis of sorted upper cortical neurons further revealed that neurons continue to express genes related to cell cycle progression long after mitotic exit until at least post-natal day 3 (P3). These genes are however down-regulated thereafter, associated with a concomitant up-regulation of tumor suppressors at P5. Interestingly, newly born neurons located in the cortical plate (CP) at embryonic day 18-19 (E18-E19) and P3 challenged with calcium influx are found in S/G2/M phases of the cell cycle, and still able to undergo division at E18-E19 but not at P3. At P5 however, calcium influx becomes neurotoxic and leads instead to neuronal loss. Our data delineate an unexpected flexibility of cell cycle control in early born neurons, and describe how neurons transit to a post-mitotic state.
Collapse
|
17
|
Abstract
Neurons are usually regarded as postmitotic cells that undergo apoptosis in response to cell cycle reactivation. Nevertheless, recent evidence indicates the existence of a defined developmental program that induces DNA replication in specific populations of neurons, which remain in a tetraploid state for the rest of their adult life. Similarly, de novo neuronal tetraploidization has also been described in the adult brain as an early hallmark of neurodegeneration. The aim of this review is to integrate these recent developments in the context of cell cycle regulation and apoptotic cell death in neurons. We conclude that a variety of mechanisms exists in neuronal cells for G1/S and G2/M checkpoint regulation. These mechanisms, which are connected with the apoptotic machinery, can be modulated by environmental signals and the neuronal phenotype itself, thus resulting in a variety of outcomes ranging from cell death at the G1/S checkpoint to full proliferation of differentiated neurons.
Collapse
Key Words
- AD, Alzheimer disease
- BDNF, brain-derived neurotrophic factor
- BrdU, 5-bromo-2′-deoxyuridine
- CKI, Cdk-inhibitor
- CNS, central nervous system
- Cdk, cyclin-dependent kinase
- Cip/Kip, cyclin inhibitor protein/kinase inhibitor protein
- G0, quiescent state
- G1, growth phase 1
- G2, growth phase 2
- Ink, inhibitor of kinase
- Mcm2, minichromosome maintenance 2
- PCNA, proliferating cell nuclear antigen
- PD, Parkinson disease
- RGCs, retinal ganglion cells
- Rb, Retinoblastoma
- S-phase
- S-phase, synthesis phase.
- apoptosis
- cell cycle re-entry
- mitosis
- neuron
- p38MAPK, p38 mitogen-activated protein kinase
- p75NTR, neurotrophin receptor p75
- tetraploid
Collapse
Affiliation(s)
- José M Frade
- a Department of Molecular, Cellular and Developmental Neurobiology; Instituto Cajal; Consejo Superior de Investigaciones Científicas (IC-CSIC) ; Madrid , Spain
| | | |
Collapse
|
18
|
Physiological and pathophysiological functions of cell cycle proteins in post-mitotic neurons: implications for Alzheimer's disease. Acta Neuropathol 2015; 129:511-25. [PMID: 25618528 PMCID: PMC4366542 DOI: 10.1007/s00401-015-1382-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/02/2015] [Accepted: 01/03/2015] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder for which no effective treatment is available. Increased insight into the disease mechanism in early stages of pathology is required for the development of a successful therapy. Over the years, numerous studies have shown that cell cycle proteins are expressed in neurons of AD patients. Traditionally, neurons are considered to be post-mitotic, which means that they permanently retract from the cell cycle. The expression of cell cycle proteins in adult neurons of AD patients has therefore been suggested to promote or even instigate pathomechanisms underlying AD. Interestingly, expression of cell cycle proteins is detected in post-mitotic neurons of healthy controls as well, albeit to a lesser extent than in AD patients. This indicates that cell cycle proteins may serve important physiological functions in differentiated neurons. Here, we provide an overview of studies that support a role of cell cycle proteins in DNA repair and neuroplasticity in post-mitotic neurons. Aberrant control of these processes could, in turn, contribute to cell cycle-mediated neurodegeneration. The balance between regenerative and degenerative effects of cell cycle proteins in post-mitotic neurons might change throughout the different stages of AD. In the early stages of AD pathology, cell cycle protein expression may primarily occur to aid in the repair of sublethal double-strand breaks in DNA. With the accumulation of pathology, cell cycle-mediated neuroplasticity and neurodegeneration may become more predominant. Understanding the physiological and pathophysiological role of cell cycle proteins in AD could give us more insight into the neurodegenerative process in AD.
Collapse
|
19
|
Biferi MG, Nicoletti C, Falcone G, Puggioni EMR, Passaro N, Mazzola A, Pajalunga D, Zaccagnini G, Rizzuto E, Auricchio A, Zentilin L, De Luca G, Giacca M, Martelli F, Musio A, Musarò A, Crescenzi M. Proliferation of Multiple Cell Types in the Skeletal Muscle Tissue Elicited by Acute p21 Suppression. Mol Ther 2015; 23:885-895. [PMID: 25669433 DOI: 10.1038/mt.2015.27] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 02/03/2015] [Indexed: 12/20/2022] Open
Abstract
Although in the last decades the molecular underpinnings of the cell cycle have been unraveled, the acquired knowledge has been rarely translated into practical applications. Here, we investigate the feasibility and safety of triggering proliferation in vivo by temporary suppression of the cyclin-dependent kinase inhibitor, p21. Adeno-associated virus (AAV)-mediated, acute knockdown of p21 in intact skeletal muscles elicited proliferation of multiple, otherwise quiescent cell types, notably including satellite cells. Compared with controls, p21-suppressed muscles exhibited a striking two- to threefold expansion in cellularity and increased fiber numbers by 10 days post-transduction, with no detectable inflammation. These changes partially persisted for at least 60 days, indicating that the muscles had undergone lasting modifications. Furthermore, morphological hyperplasia was accompanied by 20% increases in maximum strength and resistance to fatigue. To assess the safety of transiently suppressing p21, cells subjected to p21 knockdown in vitro were analyzed for γ-H2AX accumulation, DNA fragmentation, cytogenetic abnormalities, ploidy, and mutations. Moreover, the differentiation competence of p21-suppressed myoblasts was investigated. These assays confirmed that transient suppression of p21 causes no genetic damage and does not impair differentiation. Our results establish the basis for further exploring the manipulation of the cell cycle as a strategy in regenerative medicine.
Collapse
Affiliation(s)
- Maria Grazia Biferi
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
| | - Carmine Nicoletti
- Institute Pasteur Cenci-Bolognetti, DAHFMO-Unit of Histology and Medical Embryology, IIM, Sapienza University of Rome, Rome, Italy
| | - Germana Falcone
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy; Institute of Cell Biology and Neurobiology, National Research Council, Monterotondo, Italy
| | - Eleonora M R Puggioni
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
| | - Nunzia Passaro
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
| | - Alessia Mazzola
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
| | - Deborah Pajalunga
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
| | - Germana Zaccagnini
- Molecular Cardiology Laboratory, IRCCS-Policlinico San Donato, Milan, Italy
| | - Emanuele Rizzuto
- Department of Mechanical and Aerospace Engineering, IIM, Sapienza University of Rome, Rome, Italy
| | - Alberto Auricchio
- Division of Medical Genetics, Department of Translational Medicine, "Federico II" University, Naples, Italy; Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | - Lorena Zentilin
- Molecular Medicine Laboratory, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Gabriele De Luca
- Department of Ematology, Oncology and Molecular Medicine, National Institute of Health, Rome, Italy
| | - Mauro Giacca
- Molecular Medicine Laboratory, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Fabio Martelli
- Molecular Cardiology Laboratory, IRCCS-Policlinico San Donato, Milan, Italy
| | - Antonio Musio
- Institute of Biomedical and Genetic Research, National Research Council, Pisa, Italy; Tumour Institute of Tuscany, Florence, Italy
| | - Antonio Musarò
- Institute Pasteur Cenci-Bolognetti, DAHFMO-Unit of Histology and Medical Embryology, IIM, Sapienza University of Rome, Rome, Italy; Center for Life Nano Science@Sapienza, Italian Institute of Technology, Genova, Italy
| | - Marco Crescenzi
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy.
| |
Collapse
|
20
|
Rose SJ, Kriener LH, Heinzer AK, Fan X, Raike RS, van den Maagdenberg AMJM, Hess EJ. The first knockin mouse model of episodic ataxia type 2. Exp Neurol 2014; 261:553-62. [PMID: 25109669 DOI: 10.1016/j.expneurol.2014.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/07/2014] [Accepted: 08/01/2014] [Indexed: 12/28/2022]
Abstract
Episodic ataxia type 2 (EA2) is an autosomal dominant disorder associated with attacks of ataxia that are typically precipitated by stress, ethanol, caffeine or exercise. EA2 is caused by loss-of-function mutations in the CACNA1A gene, which encodes the α1A subunit of the CaV2.1 voltage-gated Ca(2+) channel. To better understand the pathomechanisms of this disorder in vivo, we created the first genetic animal model of EA2 by engineering a mouse line carrying the EA2-causing c.4486T>G (p.F1406C) missense mutation in the orthologous mouse Cacna1a gene. Mice homozygous for the mutated allele exhibit a ~70% reduction in CaV2.1 current density in Purkinje cells, though surprisingly do not exhibit an overt motor phenotype. Mice hemizygous for the knockin allele (EA2/- mice) did exhibit motor dysfunction measurable by rotarod and pole test. Studies using Cre-flox conditional genetics explored the role of cerebellar Purkinje cells or cerebellar granule cells in the poor motor performance of EA2/- mice and demonstrate that manipulation of either cell type alone did not cause poor motor performance. Thus, it is possible that subtle dysfunction arising from multiple cell types is necessary for the expression of certain ataxia syndromes.
Collapse
Affiliation(s)
- Samuel J Rose
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Lisa H Kriener
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ann K Heinzer
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Xueliang Fan
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Robert S Raike
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Arn M J M van den Maagdenberg
- Department of Human Genetics, Leiden University Medical Centre, 2300 RC Leiden, The Netherlands; Department of Neurology, Leiden University Medical Centre, 2300 RC Leiden, The Netherlands
| | - Ellen J Hess
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| |
Collapse
|
21
|
Guan X, Duan Y, Zeng Q, Pan H, Qian Y, Li D, Cao X, Liu M. Lgr4 protein deficiency induces ataxia-like phenotype in mice and impairs long term depression at cerebellar parallel fiber-Purkinje cell synapses. J Biol Chem 2014; 289:26492-26504. [PMID: 25063812 DOI: 10.1074/jbc.m114.564138] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cerebellar dysfunction causes ataxia characterized by loss of balance and coordination. Until now, the molecular and neuronal mechanisms of several types of inherited cerebellar ataxia have not been completely clarified. Here, we report that leucine-rich G protein-coupled receptor 4 (Lgr4/Gpr48) is highly expressed in Purkinje cells (PCs) in the cerebellum. Deficiency of Lgr4 leads to an ataxia-like phenotype in mice. Histologically, no obvious morphological changes were observed in the cerebellum of Lgr4 mutant mice. However, the number of PCs was slightly but significantly reduced in Lgr4(-/-) mice. In addition, in vitro electrophysiological analysis showed an impaired long term depression (LTD) at parallel fiber-PC (PF-PC) synapses in Lgr4(-/-) mice. Consistently, immunostaining experiments showed that the level of phosphorylated cAMP-responsive element-binding protein (Creb) was significantly decreased in Lgr4(-/-) PCs. Furthermore, treatment with forskolin, an adenylyl cyclase agonist, rescued phospho-Creb in PCs and reversed the impairment in PF-PC LTD in Lgr4(-/-) cerebellar slices, indicating that Lgr4 is an upstream regulator of Creb signaling, which is underlying PF-PC LTD. Together, our findings demonstrate for first time an important role for Lgr4 in motor coordination and cerebellar synaptic plasticity and provide a potential therapeutic target for certain types of inherited cerebellar ataxia.
Collapse
Affiliation(s)
- Xin Guan
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, and East China Normal University, Shanghai 200241, China
| | - Yanhong Duan
- Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, Shanghai 200241, China, and
| | - Qingwen Zeng
- Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, Shanghai 200241, China, and
| | - Hongjie Pan
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, and East China Normal University, Shanghai 200241, China
| | - Yu Qian
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, and East China Normal University, Shanghai 200241, China
| | - Dali Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, and East China Normal University, Shanghai 200241, China.
| | - Xiaohua Cao
- Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, Shanghai 200241, China, and.
| | - Mingyao Liu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, and East China Normal University, Shanghai 200241, China; Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, Texas 77030.
| |
Collapse
|
22
|
Turner RL, Wilkinson JC, Ornelles DA. E1B and E4 oncoproteins of adenovirus antagonize the effect of apoptosis inducing factor. Virology 2014; 456-457:205-19. [PMID: 24889240 DOI: 10.1016/j.virol.2014.03.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 02/28/2014] [Accepted: 03/10/2014] [Indexed: 01/03/2023]
Abstract
Adenovirus inundates the productively infected cell with linear, double-stranded DNA and an abundance of single-stranded DNA. The cellular response to this stimulus is antagonized by the adenoviral E1B and E4 early genes. A mutant group C adenovirus that fails to express the E1B-55K and E4orf3 genes is unable to suppress the DNA-damage response. Cells infected with this double-mutant virus display significant morphological heterogeneity at late times of infection and frequently contain fragmented nuclei. Nuclear fragmentation was due to the translocation of apoptosis inducing factor (AIF) from the mitochondria into the nucleus. The release of AIF was dependent on active poly(ADP-ribose) polymerase-1 (PARP-1), which appeared to be activated by viral DNA replication. Nuclear fragmentation did not occur in AIF-deficient cells or in cells treated with a PARP-1 inhibitor. The E1B-55K or E4orf3 proteins independently prevented nuclear fragmentation subsequent to PARP-1 activation, possibly by altering the intracellular distribution of PAR-modified proteins.
Collapse
Affiliation(s)
- Roberta L Turner
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States
| | - John C Wilkinson
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States.
| | - David A Ornelles
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States.
| |
Collapse
|
23
|
Herrup K, Carrillo MC, Schenk D, Cacace A, Desanti S, Fremeau R, Bhat R, Glicksman M, May P, Swerdlow R, Van Eldik LJ, Bain LJ, Budd S. Beyond amyloid: getting real about nonamyloid targets in Alzheimer's disease. Alzheimers Dement 2013; 9:452-458.e1. [PMID: 23809366 DOI: 10.1016/j.jalz.2013.01.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 01/28/2013] [Indexed: 10/26/2022]
Abstract
For decades, researchers have focused primarily on a pathway initiated by amyloid beta aggregation, amyloid deposition, and accumulation in the brain as the key mechanism underlying the disease and the most important treatment target. However, evidence increasingly suggests that amyloid is deposited early during the course of disease, even prior to the onset of clinical symptoms. Thus, targeting amyloid in patients with mild to moderate Alzheimer's disease (AD), as past failed clinical trials have done, may be insufficient to halt further disease progression. Scientists are investigating other molecular and cellular pathways and processes that contribute to AD pathogenesis. Thus, the Alzheimer's Association's Research Roundtable convened a meeting in April 2012 to move beyond amyloid and explore AD as a complex multifactorial disease, with the goal of using a more inclusive perspective to identify novel treatment strategies.
Collapse
Affiliation(s)
- Karl Herrup
- Hong Kong University of Science and Technology, Division of Biology Life Science, Hong Kong
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Bhaskar K, Maphis N, Xu G, Varvel NH, Kokiko-Cochran ON, Weick JP, Staugaitis SM, Cardona A, Ransohoff RM, Herrup K, Lamb BT. Microglial derived tumor necrosis factor-α drives Alzheimer's disease-related neuronal cell cycle events. Neurobiol Dis 2013; 62:273-85. [PMID: 24141019 DOI: 10.1016/j.nbd.2013.10.007] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Revised: 10/01/2013] [Accepted: 10/06/2013] [Indexed: 01/06/2023] Open
Abstract
Massive neuronal loss is a key pathological hallmark of Alzheimer's disease (AD). However, the mechanisms are still unclear. Here we demonstrate that neuroinflammation, cell autonomous to microglia, is capable of inducing neuronal cell cycle events (CCEs), which are toxic for terminally differentiated neurons. First, oligomeric amyloid-beta peptide (AβO)-mediated microglial activation induced neuronal CCEs via the tumor-necrosis factor-α (TNFα) and the c-Jun Kinase (JNK) signaling pathway. Second, adoptive transfer of CD11b+ microglia from AD transgenic mice (R1.40) induced neuronal cyclin D1 expression via TNFα signaling pathway. Third, genetic deficiency of TNFα in R1.40 mice (R1.40-Tnfα(-/-)) failed to induce neuronal CCEs. Finally, the mitotically active neurons spatially co-exist with F4/80+ activated microglia in the human AD brain and that a portion of these neurons are apoptotic. Together our data suggest a cell-autonomous role of microglia, and identify TNFα as the responsible cytokine, in promoting neuronal CCEs in the pathogenesis of AD.
Collapse
Affiliation(s)
- Kiran Bhaskar
- Department of Molecular Genetics and Microbiology, University of New Mexico, MSC08 4660, 1 University of New Mexico, Albuquerque, NM 87131, USA.
| | - Nicole Maphis
- Department of Molecular Genetics and Microbiology, University of New Mexico, MSC08 4660, 1 University of New Mexico, Albuquerque, NM 87131, USA.
| | - Guixiang Xu
- Department of Neurosciences, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
| | - Nicholas H Varvel
- Department of Cellular Neurology, University of Tübingen, Hertie Institute for Clinical Brain Research, Otfried-Müller-Straße 27, 72076 Tübingen, Germany.
| | - Olga N Kokiko-Cochran
- Department of Neurosciences, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
| | - Jason P Weick
- Department of Neurosciences, University of New Mexico, MSC08 4740, 1 University of New Mexico, Albuquerque, NM 87131, USA.
| | - Susan M Staugaitis
- Department of Neurosciences, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
| | - Astrid Cardona
- Department of Biology, University of Texas San Antonio, West Campus/Tobin lab MBT 1.216, San Antonio, TX 78249, USA.
| | - Richard M Ransohoff
- Department of Neurosciences, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
| | - Karl Herrup
- Department of Cell Biology and Neuroscience, Rutgers University, Nelson Hall, Busch Campus, Piscataway, NJ 08855, USA.
| | - Bruce T Lamb
- Department of Neurosciences, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
| |
Collapse
|
25
|
Herrup K. ATM and the epigenetics of the neuronal genome. Mech Ageing Dev 2013; 134:434-9. [PMID: 23707635 DOI: 10.1016/j.mad.2013.05.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/01/2013] [Accepted: 05/17/2013] [Indexed: 01/28/2023]
Abstract
Ataxia-telangiectasia (A-T) is a neurodegenerative syndrome caused by the mutation of the ATM gene. The ATM protein is a PI3kinase family member best known for its role in the DNA damage response. While repair of DNA damage is a critical function that every CNS neuron must perform, a growing body of evidence indicates that the full range of ATM functions includes some that are unrelated to DNA damage yet are essential to neuronal survival and normal function. For example, ATM participates in the regulation of synaptic vesicle trafficking and is essential for the maintenance of normal LTP. In addition ATM helps to ensure the cytoplasmic localization of HDAC4 and thus maintains the histone 'code' of the neuronal genome by suppressing genome-wide histone deacetylation, which alters the message and protein levels of many genes that are important for neuronal survival and function. The growing list of ATM functions that go beyond its role in the DNA damage response offers a new perspective on why individuals with A-T express such a wide range of neurological symptoms, and suggests that not all A-T symptoms need to be understood in the context of the DNA repair process.
Collapse
Affiliation(s)
- Karl Herrup
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, United States; Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
| |
Collapse
|
26
|
Oshikawa M, Okada K, Nakajima K, Ajioka I. Cortical excitatory neurons become protected from cell division during neurogenesis in an Rb family-dependent manner. Development 2013; 140:2310-20. [PMID: 23615279 DOI: 10.1242/dev.095653] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cell cycle dysregulation leads to abnormal proliferation and cell death in a context-specific manner. Cell cycle progression driven via the Rb pathway forces neurons to undergo S-phase, resulting in cell death associated with the progression of neuronal degeneration. Nevertheless, some Rb- and Rb family (Rb, p107 and p130)-deficient differentiating neurons can proliferate and form tumors. Here, we found in mouse that differentiating cerebral cortical excitatory neurons underwent S-phase progression but not cell division after acute Rb family inactivation in differentiating neurons. However, the differentiating neurons underwent cell division and proliferated when Rb family members were inactivated in cortical progenitors. Differentiating neurons generated from Rb(-/-); p107(-/-); p130(-/-) (Rb-TKO) progenitors, but not acutely inactivated Rb-TKO differentiating neurons, activated the DNA double-strand break (DSB) repair pathway without increasing trimethylation at lysine 20 of histone H4 (H4K20), which has a role in protection against DNA damage. The activation of the DSB repair pathway was essential for the cell division of Rb-TKO differentiating neurons. These results suggest that newly born cortical neurons from progenitors become epigenetically protected from DNA damage and cell division in an Rb family-dependent manner.
Collapse
Affiliation(s)
- Mio Oshikawa
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
| | | | | | | |
Collapse
|
27
|
ivkovic L, Spremo-Potparevic B, Siedlak SL, Perry G, Pleca-Solarovic B, Milicevic Z, Bajic VP. DNA Damage in Alzheimer Disease Lymphocytes and Its Relation to Premature Centromere Division. NEURODEGENER DIS 2013; 12:156-63. [DOI: 10.1159/000346114] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 11/27/2012] [Indexed: 11/19/2022] Open
|
28
|
Park CR, Kim DK, Cho EB, You DJ, do Rego JL, Vaudry D, Sun W, Kim H, Seong JY, Hwang JI. Spatiotemporal expression and functional implication of CXCL14 in the developing mice cerebellum. Mol Cells 2012; 34:289-93. [PMID: 22843118 PMCID: PMC3887834 DOI: 10.1007/s10059-012-0116-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/14/2012] [Accepted: 06/19/2012] [Indexed: 12/22/2022] Open
Abstract
Cerebellar granule neurons migrate from the external granule cell layer (EGL) to the internal granule cell layer (IGL) during postnatal morphogenesis. This migration process through 4 different layers is a complex mechanism which is highly regulated by many secreted proteins. Although chemokines are well-known peptides that trigger cell migration, but with the exception of CXCL12, which is responsible for prenatal EGL formation, their functions have not been thoroughly studied in granule cell migration. In the present study, we examined cerebellar CXCL14 expression in neonatal and adult mice. CXCL14 mRNA was expressed at high levels in adult mouse cerebellum, but the protein was not detected. Nevertheless, Western blotting analysis revealed transient expression of CXCL14 in the cerebellum in early postnatal days (P1, P8), prior to the completion of granule cell migration. Looking at the distribution of CXCL14 by immunohistochemistry revealed a strong immune reactivity at the level of the Purkinje cell layer and molecular layer which was absent in the adult cerebellum. In functional assays, CXCL14 stimulated transwell migration of cultured granule cells and enhanced the spreading rate of neurons from EGL microexplants. Taken together, these results revealed the transient expression of CXCL14 by Purkinje cells in the developing cerebellum and demonstrate the ability of the chemokine to stimulate granule cell migration, suggesting that it must be involved in the postnatal maturation of the cerebellum.
Collapse
Affiliation(s)
- Cho Rong Park
- Graduate School of Medicine, Korea University College of Medicine, Seoul 136-705,
Korea
| | - Dong-Kyu Kim
- Graduate School of Medicine, Korea University College of Medicine, Seoul 136-705,
Korea
| | - Eun Bee Cho
- Graduate School of Medicine, Korea University College of Medicine, Seoul 136-705,
Korea
| | - Dong-Joo You
- Graduate School of Medicine, Korea University College of Medicine, Seoul 136-705,
Korea
| | - Jean Luc do Rego
- Institut National de la Santé et de la Recherche Médicale (INSERM), Institute for Research and Innovation in Biomedicine (IRIB), Regional Platform for Cell Imaging (PRIMACEN), International Associate Laboratory Samuel de Champlain, University of Rouen,
France
| | - David Vaudry
- Institut National de la Santé et de la Recherche Médicale (INSERM), Institute for Research and Innovation in Biomedicine (IRIB), Regional Platform for Cell Imaging (PRIMACEN), International Associate Laboratory Samuel de Champlain, University of Rouen,
France
| | - Woong Sun
- Department of Anatomy, Korea University College of Medicine, Seoul 136-705,
Korea
| | - Hyun Kim
- Department of Anatomy, Korea University College of Medicine, Seoul 136-705,
Korea
| | - Jae Young Seong
- Graduate School of Medicine, Korea University College of Medicine, Seoul 136-705,
Korea
| | - Jong-Ik Hwang
- Graduate School of Medicine, Korea University College of Medicine, Seoul 136-705,
Korea
| |
Collapse
|
29
|
Raike RS, Pizoli CE, Weisz C, van den Maagdenberg AMJM, Jinnah HA, Hess EJ. Limited regional cerebellar dysfunction induces focal dystonia in mice. Neurobiol Dis 2012; 49:200-10. [PMID: 22850483 DOI: 10.1016/j.nbd.2012.07.019] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 07/11/2012] [Accepted: 07/20/2012] [Indexed: 11/25/2022] Open
Abstract
Dystonia is a complex neurological syndrome broadly characterized by involuntary twisting movements and abnormal postures. The anatomical distribution of the motor symptoms varies among dystonic patients and can range from focal, involving an isolated part of the body, to generalized, involving many body parts. Functional imaging studies of both focal and generalized dystonias in humans often implicate the cerebellum suggesting that similar pathological processes may underlie both. To test this, we exploited tools developed in mice to generate animals with gradients of cerebellar dysfunction. By using conditional genetics to regionally limit cerebellar dysfunction, we found that abnormalities restricted to Purkinje cells were sufficient to cause dystonia. In fact, the extent of cerebellar dysfunction determined the extent of abnormal movements. Dysfunction of the entire cerebellum caused abnormal postures of many body parts, resembling generalized dystonia. More limited regions of dysfunction that were created by electrical stimulation or conditional genetic manipulations produced abnormal movements in an isolated body part, resembling focal dystonia. Overall, these results suggest that focal and generalized dystonias may arise through similar mechanisms and therefore may be approached with similar therapeutic strategies.
Collapse
Affiliation(s)
- Robert S Raike
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Carolyn E Pizoli
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Catherine Weisz
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Arn M J M van den Maagdenberg
- Department of Human Genetics, Leiden University Medical Centre, 2300 RC Leiden, The Netherlands; Department of Neurology, Leiden University Medical Centre, 2300 RC Leiden, The Netherlands
| | - H A Jinnah
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ellen J Hess
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| |
Collapse
|
30
|
Aranda-Anzaldo A. The post-mitotic state in neurons correlates with a stable nuclear higher-order structure. Commun Integr Biol 2012; 5:134-9. [PMID: 22808316 PMCID: PMC3376047 DOI: 10.4161/cib.18761] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Neurons become terminally differentiated (TD) post-mitotic cells very early during development yet they may remain alive and functional for decades. TD neurons preserve the molecular machinery necessary for DNA synthesis that may be reactivated by different stimuli but they never complete a successful mitosis. The non-reversible nature of the post-mitotic state in neurons suggests a non-genetic basis for it since no set of mutations has been able to revert it. Comparative studies of the nuclear higher-order structure in neurons and cells with proliferating potential suggest that the non-reversible nature of the post-mitotic state in neurons has a structural basis in the stability of the nuclear higher-order structure.
Collapse
Affiliation(s)
- Armando Aranda-Anzaldo
- Laboratorio de Biología Molecular; Facultad de Medicina; Universidad Autónoma del Estado de México; Toluca, México
| |
Collapse
|
31
|
Van Hove I, Verslegers M, Buyens T, Delorme N, Lemmens K, Stroobants S, Gantois I, D'Hooge R, Moons L. An aberrant cerebellar development in mice lacking matrix metalloproteinase-3. Mol Neurobiol 2011; 45:17-29. [PMID: 22108898 DOI: 10.1007/s12035-011-8215-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 10/24/2011] [Indexed: 11/30/2022]
Abstract
Cell-cell and cell-matrix interactions are necessary for neuronal patterning and brain wiring during development. Matrix metalloproteinases (MMPs) are proteolytic enzymes capable of remodelling the pericellular environment and regulating signaling pathways through cleavage of a large degradome. MMPs have been suggested to affect cerebellar development, but the specific role of different MMPs in cerebellar morphogenesis remains unclear. Here, we report a role for MMP-3 in the histogenesis of the mouse cerebellar cortex. MMP-3 expression peaks during the second week of postnatal cerebellar development and is most prominently observed in Purkinje cells (PCs). In MMP-3 deficient (MMP-3(-/-)) mice, a protracted granule cell (GC) tangential migration and a delayed GC radial migration results in a thicker and persistent external granular layer, a retarded arrival of GCs in the inner granular layer, and a delayed GABAergic interneuron migration. Importantly, these neuronal migration anomalies, as well as the consequent disturbed synaptogenesis on PCs, seem to be caused by an abnormal PC dendritogenesis, which results in reduced PC dendritic trees in the adult cerebellum. Of note, these developmental and adult cerebellar defects might contribute to the aberrant motor phenotype observed in MMP-3(-/-) mice and suggest an involvement of MMP-3 in mouse cerebellar development.
Collapse
Affiliation(s)
- Inge Van Hove
- Laboratory of Neural Circuit Development and Regeneration, Animal Physiology and Neurobiology Section, Department of Biology, K.U.Leuven, Naamsestraat 61, Box 2464, 3000 Leuven, Belgium
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Pajovic S, Corson TW, Spencer C, Dimaras H, Orlic-Milacic M, Marchong MN, To KH, Thériault B, Auspitz M, Gallie BL. The TAg-RB murine retinoblastoma cell of origin has immunohistochemical features of differentiated Muller glia with progenitor properties. Invest Ophthalmol Vis Sci 2011; 52:7618-24. [PMID: 21862643 DOI: 10.1167/iovs.11-7989] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
PURPOSE Human retinoblastoma arises from an undefined developing retinal cell after inactivation of RB1. This is emulated in a murine retinoblastoma model by inactivation of pRB by retinal-specific expression of simian virus 40 large T-antigen (TAg-RB). Some mutational events after RB1 loss in humans are recapitulated at the expression level in TAg-RB, supporting preclinical evidence that this model is useful for comparative studies between mouse and human. Here, the characteristics of the TAg-RB cell of origin are defined. METHODS TAg-RB mice were killed at ages from embryonic day (E)18 to postnatal day (P)35. Tumors were analyzed by immunostaining, DNA copy number PCR, or real-time quantitative RT-PCR for TAg protein, retinal cell type markers, and retinoblastoma-relevant genes. RESULTS TAg expression began at P8 in a row of inner nuclear layer cells that increased in number through P21 to P28, when clusters reminiscent of small tumors emerged from cells that escaped a wave of apoptosis. Early TAg-expressing cells coexpressed the developmental marker Chx10 and glial markers CRALBP, clusterin, and carbonic anhydrase II (Car2), but not TuJ1, an early neuronal marker. Emerging tumors retained expression of only Chx10 and carbonic anhydrase II. As with human retinoblastoma, TAg-RB tumors showed decreased Cdh11 DNA copy number and gain of Kif14 and Mycn. It was confirmed that TAg-RB tumors lose expression of tumor suppressor cadherin-11 and overexpress oncogenes Kif14, Dek, and E2f3. CONCLUSIONS TAg-RB tumors displayed molecular similarity to human retinoblastoma and origin in a cell with features of differentiated Müller glia with progenitor properties.
Collapse
Affiliation(s)
- Sanja Pajovic
- Division of Applied Molecular Oncology, Ontario Cancer Institute/Princess Margaret Hospital, Toronto, Ontario, Canada
| | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Mithramycin is a gene-selective Sp1 inhibitor that identifies a biological intersection between cancer and neurodegeneration. J Neurosci 2011; 31:6858-70. [PMID: 21543616 DOI: 10.1523/jneurosci.0710-11.2011] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Oncogenic transformation of postmitotic neurons triggers cell death, but the identity of genes critical for degeneration remain unclear. The antitumor antibiotic mithramycin prolongs survival of mouse models of Huntington's disease in vivo and inhibits oxidative stress-induced death in cortical neurons in vitro. We had correlated protection by mithramycin with its ability to bind to GC-rich DNA and globally displace Sp1 family transcription factors. To understand how antitumor drugs prevent neurodegeneration, here we use structure-activity relationships of mithramycin analogs to discover that selective DNA-binding inhibition of the drug is necessary for its neuroprotective effect. We identify several genes (Myc, c-Src, Hif1α, and p21(waf1/cip1)) involved in neoplastic transformation, whose altered expression correlates with protective doses of mithramycin or its analogs. Most interestingly, inhibition of one these genes, Myc, is neuroprotective, whereas forced expression of Myc induces Rattus norvegicus neuronal cell death. These results support a model in which cancer cell transformation shares key genetic components with neurodegeneration.
Collapse
|
34
|
Alva-Medina J, Maya-Mendoza A, Dent MAR, Aranda-Anzaldo A. Continued stabilization of the nuclear higher-order structure of post-mitotic neurons in vivo. PLoS One 2011; 6:e21360. [PMID: 21731716 PMCID: PMC3121788 DOI: 10.1371/journal.pone.0021360] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 05/26/2011] [Indexed: 11/19/2022] Open
Abstract
Background Cellular terminal differentiation (TD) correlates with a permanent exit from the cell cycle and so TD cells become stably post-mitotic. However, TD cells express the molecular machinery necessary for cell proliferation that can be reactivated by experimental manipulation, yet it has not been reported the stable proliferation of any type of reactivated TD cells. Neurons become post-mitotic after leaving the ventricular zone. When neurons are forced to reenter the cell cycle they invariably undergo cell death. Wider evidence indicates that the post-mitotic state cannot solely depend on gene products acting in trans, otherwise mutations in the corresponding genes may lead to reentry and completion of the cell cycle in TD cells, but this has not been observed. In the interphase, nuclear DNA of metazoan cells is organized in supercoiled loops anchored to a nuclear nuclear matrix (NM). The DNA-NM interactions define a higher-order structure in the cell nucleus (NHOS). We have previously compared the NHOS of aged rat hepatocytes with that of early post-mitotic rat neurons and our results indicated that a very stable NHOS is a common feature of both senescent and post-mitotic cells in vivo. Principal Findings In the present work we compared the NHOS in rat neurons from different post-natal ages. Our results show that the trend towards further stabilization of the NHOS in neurons continues throughout post-natal life. This phenomenon occurs in absence of overt changes in the post-mitotic state and transcriptional activity of neurons, suggesting that it is independent of functional constraints. Conclusions Apparently the continued stabilization of the NHOS as a function of time is basically determined by thermodynamic and structural constraints. We discuss how the resulting highly stable NHOS of neurons may be the structural, non-genetic basis of their permanent and irreversible post-mitotic state.
Collapse
Affiliation(s)
- Janeth Alva-Medina
- Laboratorio de Biología Molecular y Neurociencias, Facultad de Medicina, Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Apolinar Maya-Mendoza
- Laboratorio de Biología Molecular y Neurociencias, Facultad de Medicina, Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Myrna A. R. Dent
- Laboratorio de Biología Molecular y Neurociencias, Facultad de Medicina, Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Armando Aranda-Anzaldo
- Laboratorio de Biología Molecular y Neurociencias, Facultad de Medicina, Universidad Autónoma del Estado de México, Toluca, Estado de México, México
- * E-mail:
| |
Collapse
|
35
|
Baratchi S, Kanwar RK, Kanwar JR. Survivin: A target from brain cancer to neurodegenerative disease. Crit Rev Biochem Mol Biol 2010; 45:535-54. [DOI: 10.3109/10409238.2010.516740] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
36
|
Yap YW, Chen MJ, Choy MS, Peng ZF, Whiteman M, Manikandan J, Melendez AJ, Cheung NS. Temporal transcriptomic profiling reveals cellular targets that govern survival in HOCl-mediated neuronal apoptosis. Life Sci 2010; 87:457-67. [DOI: 10.1016/j.lfs.2010.08.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 08/02/2010] [Accepted: 08/19/2010] [Indexed: 12/19/2022]
|
37
|
Abstract
Historically basic neuroscience research has made several important contributions to the cell biology of the nucleus, in particular the elucidation of nuclear structures and compartments. As research progressed towards elucidating the mechanism of neurological disease at the cellular and molecular levels, it is now providing insight into the importance and basis of coordination of nuclear pathways within the nucleus and with other cellular compartments. Ataxias, lethal neurodegenerative diseases that are distinguished by a progressive loss of motor coordination, stem from disruption of nuclear function.
Collapse
Affiliation(s)
- Harry T Orr
- Institute of Translational Neuroscience, Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota 55455, USA.
| |
Collapse
|
38
|
Pajalunga D, Puggioni EMR, Mazzola A, Leva V, Montecucco A, Crescenzi M. DNA replication is intrinsically hindered in terminally differentiated myotubes. PLoS One 2010; 5:e11559. [PMID: 20644635 PMCID: PMC2903488 DOI: 10.1371/journal.pone.0011559] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Accepted: 06/18/2010] [Indexed: 12/15/2022] Open
Abstract
Background Terminally differentiated (TD) cells permanently exit the mitotic cycle while acquiring specialized characteristics. Although TD cells can be forced to reenter the cell cycle by different means, they cannot be made to stably proliferate, as attempts to induce their replication constantly result in cell death or indefinite growth arrest. There is currently no biological explanation for this failure. Principal Findings Here we show that TD mouse myotubes, reactivated by depletion of the p21 and p27 cell cycle inhibitors, are unable to complete DNA replication and sustain heavy DNA damage, which triggers apoptosis or results in mitotic catastrophe. In striking contrast, quiescent, non-TD fibroblasts and myoblasts, reactivated in the same way, fully replicate their DNA, do not suffer DNA damage, and proliferate even in the absence of growth factors. Similar results are obtained when myotubes and fibroblasts are reactivated by forced expression of E1A or cyclin D1 and cdk4. Conclusions We conclude that the inability of myotubes to complete DNA replication must be ascribed to peculiar features inherent in their TD state, rather than to the reactivation method. On reviewing the literature concerning reactivation of other TD cell types, we propose that similar mechanisms underlie the general inability of all kinds of TD cells to proliferate in response to otherwise mitogenic stimuli. These results define an unexpected basis for the well known incompetence of mammalian postmitotic cells to proliferate. Furthermore, this trait might contribute to explain the inability of these cells to play a role in tissue repair, unlike their counterparts in extensively regenerating species.
Collapse
Affiliation(s)
- Deborah Pajalunga
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
| | | | - Alessia Mazzola
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
| | - Valentina Leva
- Institute of Molecular Genetics, National Research Council, Pavia, Italy
| | | | - Marco Crescenzi
- Department of Cell Biology and Neurosciences, National Institute of Health, Rome, Italy
- * E-mail:
| |
Collapse
|
39
|
Abstract
The complex neurodegeneration underlying Alzheimer disease (AD), although incompletely understood, is characterised by an aberrant re-entry into the cell cycle in neurons. Pathological evidence, in the form of cell cycle markers and regulatory proteins, suggests that cell cycle re-entry is an early event in AD, which precedes the formation of amyloid-beta plaques and neurofibrillary tangles (NFTs). Although the exact mechanisms that induce and mediate these cell cycle events in AD are not clear, significant advances have been made in further understanding the pathological role of cell cycle re-entry in AD. Importantly, recent studies indicate that cell cycle re-entry is not a consequence, but rather a cause, of neurodegeneration, suggesting that targeting of cell cycle re-entry may provide an opportunity for therapeutic intervention. Moreover, multiple inducers of cell cycle re-entry and their interactions in AD have been proposed. Here, we review the most recent advances in understanding the pathological implications of cell cycle re-entry in AD.
Collapse
|
40
|
Pierce DR, Hayar A, Williams DK, Light KE. Developmental alterations in olivary climbing fiber distribution following postnatal ethanol exposure in the rat. Neuroscience 2010; 169:1438-48. [PMID: 20542091 DOI: 10.1016/j.neuroscience.2010.06.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 06/04/2010] [Accepted: 06/07/2010] [Indexed: 01/01/2023]
Abstract
Ethanol exposure during postnatal days (PN) 4-6 in rats alters cerebellar development resulting in significant loss of Purkinje cells. There is little knowledge, however, on what happens to the neurons that survive. In this study, rat pups were treated with a daily dose of ethanol (either 3.6 or 4.5 g/kg body weight) delivered by intragastric intubation on PN4, PN4-6, or PN7-9. Then the interactions between climbing fibers and Purkinje cells were examined on PN14 using confocal microscopy. Mid-vermal cerebellar sections were stained with antibodies to calbindin-D28k (to visualize Purkinje cells) and vesicular glutamate transporter 2 (VGluT2, to visualize climbing fibers). Confocal z-stack images were obtained from Lobule 1 and analyzed with Imaris software to quantify the staining of the two antibodies. The VGluT2 immunostaining was significantly reduced in the PN4 and PN4-6 ethanol groups for the 4.5 g/kg dose level, compared to controls, indicating that the cerebellar circuitry was significantly altered following developmental ethanol exposure. Not only were there fewer Purkinje cells following ethanol exposure, but the surviving neurons had significantly fewer VGluT2-labeled synapses. These alterations in the synaptic integrity were both dose dependent and temporally dependent.
Collapse
Affiliation(s)
- D R Pierce
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, 4301 W Markham Street, #522-3 Little Rock, AR 72205-7199, USA.
| | | | | | | |
Collapse
|
41
|
Casadesus G, Puig ER, Webber KM, Atwood CS, Escuer MC, Bowen RL, Perry G, Smith MA. Targeting gonadotropins: an alternative option for Alzheimer disease treatment. J Biomed Biotechnol 2010; 2006:39508. [PMID: 17047306 PMCID: PMC1559918 DOI: 10.1155/jbb/2006/39508] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Recent evidence indicates that, alongside oxidative stress, dysregulation of the cell cycle in neurons susceptible to degeneration in Alzheimer disease may play a crucial role in the initiation of the disease. As such, the role of reproductive hormones, which are closely associated with the cell cycle both during development and after birth, may be of key import. While estrogen has been the primary focus, the protective effects of hormone replacement therapy on cognition and dementia only during a “crucial period” led us to expand the study of hormonal influences to other members of the hypothalamic pituitary axis. Specifically, in this review, we focus on luteinizing hormone, which is not only increased in the sera of patients with Alzheimer disease but, like estrogen, is modulated by hormone replacement therapy and also influences cognitive behavior and pathogenic processing in animal models of the disease. Targeting gonadotropins may be a useful treatment strategy for disease targeting multiple pleiotropic downstream consequences.
Collapse
Affiliation(s)
- Gemma Casadesus
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Emma Ramiro Puig
- Departament de Fisiologia, Facultat de Farmacia, Universitat de Barcelona, Barcelona 08028, Spain
| | - Kate M. Webber
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Craig S. Atwood
- School of Medicine, University of Wisconsin and William S. Middleton Memorial Veterans Administration, Madison, WI 53705,
USA
| | - Margarida Castell Escuer
- Departament de Fisiologia, Facultat de Farmacia, Universitat de Barcelona, Barcelona 08028, Spain
| | | | - George Perry
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Mark A. Smith
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
- *Mark A. Smith:
| |
Collapse
|
42
|
Liu Y, Yang N, Zuo P. cDNA microarray analysis of gene expression in the cerebral cortex and hippocampus of BALB/c mice subjected to chronic mild stress. Cell Mol Neurobiol 2010; 30:1035-47. [PMID: 20532976 DOI: 10.1007/s10571-010-9534-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Accepted: 05/25/2010] [Indexed: 11/24/2022]
Abstract
Depressive disorders are devastating metal illness that can lead to deterioration in the social and occupational functioning of affected individuals. The etiology and pathophysiology of depression remain unknown. Present study was performed to better understand the underlying causes of depression. An experimental animal depression was induced in male BALB/c mice subjected to a chronic mild stress (CMS) procedure involving different stressor for consecutive 4 weeks. A cDNA microarray was employed to study the effects of CMS on the gene expression in cerebral cortex and hippocampus. 4-week CMS caused a significant reduction of 2% sucrose consumption. Morris water maze procedure showed impairment in cognitive function in stressed mice. Results of microarray showed that there were 102 and 60 genes were markedly affected by CMS treatment in cerebral cortex and hippocampus regions, respectively, including DNA damage/repair-related enzymes, anti-oxidant enzyme, and cyclin and cyclin-dependent kinase (CDK). These findings suggest that multiple biochemical effects play an important role the etiology of depression.
Collapse
Affiliation(s)
- Yanyong Liu
- Department of Pharmacology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College (PUMC), No. 5 Dong Dan San Tiao, Beijing, China
| | | | | |
Collapse
|
43
|
|
44
|
Zhang J, Li H, Herrup K. Cdk5 nuclear localization is p27-dependent in nerve cells: implications for cell cycle suppression and caspase-3 activation. J Biol Chem 2010; 285:14052-61. [PMID: 20189989 DOI: 10.1074/jbc.m109.068262] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Initiation of a cell cycle in an adult neuron leads to cell death, placing great importance on the mechanisms that normally suppress the neuronal cell cycle. We have previously shown that the cyclin-dependent kinase Cdk5 is an important part of this process, but only when it is present in the nucleus. We report here that Cdk5 nuclear localization relies on its binding to the cyclin-dependent kinase inhibitor p27. Cdk5 has no intrinsic nuclear localization signal; in the absence of p27, two weak nuclear export signals that bind CRM1 cause it to shuttle to the cytoplasm. When a neuron is subjected to stress, such as exposure to beta-amyloid, the Cdk5-p27 interaction is lost, reducing Cdk5 levels in the nucleus and depriving the neuron of a major cell cycle suppression mechanism. Caspase-3 is activated within hours, but death is not immediate; elevated levels of cytoplasmic Cdk5 appear to retard neuronal death by a mechanism that may involve Bcl2. These data suggest a model in which Cdk5 exerts a double protective function in neurons: chronically suppressing the cell cycle when located in the nucleus and transiently delaying cell death in the cytoplasm.
Collapse
Affiliation(s)
- Jie Zhang
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8082, USA
| | | | | |
Collapse
|
45
|
Sulg M, Kirjavainen A, Pajusola K, Bueler H, Ylikoski J, Laiho M, Pirvola U. Differential sensitivity of the inner ear sensory cell populations to forced cell cycle re-entry and p53 induction. J Neurochem 2009; 112:1513-26. [PMID: 20050971 DOI: 10.1111/j.1471-4159.2009.06563.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Previous studies have shown that the maintenance of post-mitotic state is critical for the life-long survival of the inner ear mechanosensory cells, the hair cells. A general concept is that differentiated, post-mitotic cells rapidly die following cell cycle re-entry. Here we have compared the response of postnatal cochlear (auditory) and utricular (balance) hair cells to forced cell cycle reactivation and p53 up-regulation. Forced S-phase entry was triggered through the human papillomavirus-16 E7 oncogene misexpression in explant cultures. It induced DNA damage and p53 induction in cochlear outer hair cells and these cells were rapidly lost, before entry into mitosis. The death was attenuated by p53 inactivation. In contrast, despite DNA damage and p53 induction, utricular hair cells showed longer term survival and a proportion of them progressed into mitosis. Consistently, pharmacological elevation of p53 levels by nutlin-3a led to a death-prone phenotype of cochlear outer hair cells, while other hair cell populations were death-resistant. These data have important clinical implications as they show the importance of p53 in sensory cells that are essential in hearing function.
Collapse
Affiliation(s)
- Marilin Sulg
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | | | | | | | | | | | | |
Collapse
|
46
|
Zhang Z, Cao X, Xiong N, Wang H, Huang J, Sun S, Liang Z, Wang T. DNA polymerase-β is required for 1-methyl-4-phenylpyridinium-induced apoptotic death in neurons. Apoptosis 2009; 15:105-15. [DOI: 10.1007/s10495-009-0425-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
47
|
Whitney ER, Kemper TL, Rosene DL, Bauman ML, Blatt GJ. Density of cerebellar basket and stellate cells in autism: evidence for a late developmental loss of Purkinje cells. J Neurosci Res 2009; 87:2245-54. [PMID: 19301429 PMCID: PMC2760265 DOI: 10.1002/jnr.22056] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Alterations in the cerebellum have been described as a neuropathological feature of autism. Although numerous studies have focused on the Purkinje cell (PC), the projection neuron of the cerebellar cortex, PC function is critically dependent on their innervation by the GABAergic basket cells (BCs) and stellate cells (SCs) in the cerebellar molecular layer. The present study was designed to determine whether there are differences in the packing density of these inhibitory interneurons or whether the ratio of these interneurons to PCs differs in autistic and age-matched control brains. The GABAergic interneurons were identified by using immunohistochemistry for parvalbumin (PV) in serial sections from the posterior cerebellar lobe of six autistic and four control brains and counted using stereological principles. Prior PC counts in the same area on adjacent sections (Whitney et al., 2008) were available and were used to calculate the number of BCs and SCs per PC. In this sample of brains, no statistically significant difference was detected between the autistic and the control groups in the density of BCs or SCs (P = 0.44 and P = 0.84, respectively) or in the number of BCs or SCs per PC (P = 0.47 and P = 0.44, respectively). The preservation of BCs and SCs, in the presence of the reduced PC numbers as found in at least two, and possibly three, of these six autistic cases (Whitney et al., 2008) suggests that PCs were generated, migrated to their proper location in the PC layer, and subsequently died in the autistic cases that showed a reduction in PCs.
Collapse
Affiliation(s)
- Elizabeth R Whitney
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02218-2526, USA.
| | | | | | | | | |
Collapse
|
48
|
Bajić VP, Spremo-Potparević B, Zivković L, Bonda DJ, Siedlak SL, Casadesus G, Lee HG, Smith MA. The X-chromosome instability phenotype in Alzheimer's disease: a clinical sign of accelerating aging? Med Hypotheses 2009; 73:917-20. [PMID: 19647374 DOI: 10.1016/j.mehy.2009.06.046] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Accepted: 06/24/2009] [Indexed: 10/20/2022]
Abstract
Premature centromere division, or premature centromere separation (PCS), occurs when chromatid separation is dysfunctional, occurring earlier than usual during the interphase stage of mitosis. This phenomenon, seen in Robert's syndrome and various cancers, has also been documented in peripheral as well as neuronal cells of Alzheimer's disease (AD). In the latter instances, fluorescent in situ hybridization (FISH), applied to the centromere region of the X-chromosome in interphase nuclei of lymphocytes from peripheral blood in AD patients, demonstrated premature chromosomal separation before mitotic metaphase directly after completion of DNA replication in G(2) phase of the cell cycle. Furthermore, and perhaps unexpectedly given the presumptive post-mitotic status of terminally differentiated neurons, neurons in AD patients also showed significantly increased levels of PCS of the X-chromosome. Taken together with other phenomena such as cell cycle re-activation and ectopic re-expression of cyclins and cyclin dependent proteins, we propose that AD is an oncogenic phenotype leading to accelerated aging of the affected brain.
Collapse
Affiliation(s)
- Vladan P Bajić
- Institute of Biomedical Research, Galenika ad, 11000 Belgrade, Serbia.
| | | | | | | | | | | | | | | |
Collapse
|
49
|
Cell Cycle Activation and CNS Injury. Neurotox Res 2009; 16:221-37. [PMID: 19526282 DOI: 10.1007/s12640-009-9050-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 03/26/2009] [Accepted: 03/26/2009] [Indexed: 12/28/2022]
|
50
|
Fei XF, Qin ZH, Xiang B, Li LY, Han F, Fukunaga K, Liang ZQ. Olomoucine inhibits cathepsin L nuclear translocation, activates autophagy and attenuates toxicity of 6-hydroxydopamine. Brain Res 2009; 1264:85-97. [DOI: 10.1016/j.brainres.2009.01.057] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2008] [Revised: 01/19/2009] [Accepted: 01/21/2009] [Indexed: 01/11/2023]
|