1
|
Stefano MED, Ferretti V, Mozzetta C. Synaptic alterations as a neurodevelopmental trait of Duchenne muscular dystrophy. Neurobiol Dis 2022; 168:105718. [PMID: 35390481 DOI: 10.1016/j.nbd.2022.105718] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 01/14/2023] Open
Abstract
Dystrophinopaties, e.g., Duchenne muscular dystrophy (DMD), Becker muscular dystrophy and X-linked dilated cardiomyopathy are inherited neuromuscular diseases, characterized by progressive muscular degeneration, which however associate with a significant impact on general system physiology. The more severe is the pathology and its diversified manifestations, the heavier are its effects on organs, systems, and tissues other than muscles (skeletal, cardiac and smooth muscles). All dystrophinopaties are characterized by mutations in a single gene located on the X chromosome encoding dystrophin (Dp427) and its shorter isoforms, but DMD is the most devasting: muscular degenerations manifests within the first 4 years of life, progressively affecting motility and other muscular functions, and leads to a fatal outcome between the 20s and 40s. To date, after years of studies on both DMD patients and animal models of the disease, it has been clearly demonstrated that a significant percentage of DMD patients are also afflicted by cognitive, neurological, and autonomic disorders, of varying degree of severity. The anatomical correlates underlying neural functional damages are established during embryonic development and the early stages of postnatal life, when brain circuits, sensory and motor connections are still maturing. The impact of the absence of Dp427 on the development, differentiation, and consolidation of specific cerebral circuits (hippocampus, cerebellum, prefrontal cortex, amygdala) is significant, and amplified by the frequent lack of one or more of its lower molecular mass isoforms. The most relevant aspect, which characterizes DMD-associated neurological disorders, is based on morpho-functional alterations of selective synaptic connections within the affected brain areas. This pathological feature correlates neurological conditions of DMD to other severe neurological disorders, such as schizophrenia, epilepsy and autistic spectrum disorders, among others. This review discusses the organization and the role of the dystrophin-dystroglycan complex in muscles and neurons, focusing on the neurological aspect of DMD and on the most relevant morphological and functional synaptic alterations, in both central and autonomic nervous systems, described in the pathology and its animal models.
Collapse
Affiliation(s)
- Maria Egle De Stefano
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy; Center for Research in Neurobiology Daniel Bovet, Sapienza University of Rome, 00185 Rome, Italy.
| | - Valentina Ferretti
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy; Center for Research in Neurobiology Daniel Bovet, Sapienza University of Rome, 00185 Rome, Italy
| | - Chiara Mozzetta
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR) of Italy c/o Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy
| |
Collapse
|
2
|
Persiconi I, Cosmi F, Guadagno NA, Lupo G, De Stefano ME. Dystrophin Is Required for the Proper Timing in Retinal Histogenesis: A Thorough Investigation on the mdx Mouse Model of Duchenne Muscular Dystrophy. Front Neurosci 2020; 14:760. [PMID: 32982660 PMCID: PMC7487415 DOI: 10.3389/fnins.2020.00760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 06/29/2020] [Indexed: 12/15/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a lethal X-linked muscular disease caused by defective expression of the cytoskeletal protein dystrophin (Dp427). Selected autonomic and central neurons, including retinal neurons, express Dp427 and/or dystrophin shorter isoforms. Because of this, DMD patients may also experience different forms of cognitive impairment, neurological and autonomic disorders, and specific visual defects. DMD-related damages to the nervous system are established during development, suggesting a role for all dystrophin isoforms in neural circuit development and differentiation; however, to date, their function in retinogenesis has never been investigated. In this large-scale study, we analyzed whether the lack of Dp427 affects late retinogenesis in the mdx mouse, the most well studied animal model of DMD. Retinal gene expression and layer maturation, as well as neural cell proliferation, apoptosis, and differentiation, were evaluated in E18 and/or P0, P5, P10, and adult mice. In mdx mice, expression of Capn3, Id3 (E18-P5), and Dtnb (P5) genes, encoding proteins involved in different aspects of retina development and synaptogenesis (e.g., Calpain 3, DNA-binding protein inhibitor-3, and β-dystrobrevin, respectively), was transiently reduced compared to age-matched wild type mice. Concomitantly, a difference in the time required for the retinal ganglion cell layer to reach appropriate thickness was observed (P0–P5). Immunolabeling for specific cell markers also evidenced a significant dysregulation in the number of GABAergic amacrine cells (P5–P10), a transient decrease in the area immunopositive for the Vesicular Glutamate Transporter 1 (VGluT1) during ribbon synapse maturation (P10) and a reduction in the number of calretinin+ retinal ganglion cells (RGCs) (adults). Finally, the number of proliferating retinal progenitor cells (P5–P10) and apoptotic cells (P10) was reduced. These results support the hypothesis of a role for Dp427 during late retinogenesis different from those proposed in consolidated neural circuits. In particular, Dp427 may be involved in shaping specific steps of retina differentiation. Notably, although most of the above described quantitative alterations recover over time, the number of calretinin+ RGCs is reduced only in the mature retina. This suggests that alterations subtler than the timing of retinal maturation may occur, a hypothesis that demands further in-depth functional studies.
Collapse
Affiliation(s)
- Irene Persiconi
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy.,Department of Biosciences, University of Oslo, Oslo, Norway
| | - Francesca Cosmi
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | | | - Giuseppe Lupo
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Maria Egle De Stefano
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy.,Center for Research in Neurobiology "Daniel Bovet", Sapienza University of Rome, Rome, Italy
| |
Collapse
|
3
|
Burns DP, Murphy KH, Lucking EF, O'Halloran KD. Inspiratory pressure-generating capacity is preserved during ventilatory and non-ventilatory behaviours in young dystrophic mdx mice despite profound diaphragm muscle weakness. J Physiol 2019; 597:831-848. [PMID: 30570134 DOI: 10.1113/jp277443] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 12/18/2018] [Indexed: 12/16/2022] Open
Abstract
KEY POINTS Respiratory muscle weakness is a major feature of Duchenne muscular dystrophy (DMD), yet little is known about the neural control of the respiratory muscles in DMD and animal models of dystrophic disease. Substantial diaphragm muscle weakness is apparent in young (8-week-old) mdx mice, although ventilatory capacity in response to maximum chemostimulation in conscious mice is preserved. Peak volume- and flow-related measures during chemoactivation are equivalent in anaesthetized, vagotomized wild-type and mdx mice. Diaphragm and T3 external intercostal electromyogram activities are lower during protracted sustained airway occlusion in mdx compared to wild-type mice. Yet, peak inspiratory pressure generation is remarkably well preserved. Despite profound diaphragm weakness and lower muscle activation during maximum non-ventilatory efforts, inspiratory pressure-generating capacity is preserved in young adult mdx mice, revealing compensation in support of respiratory system performance that is adequate, at least early in dystrophic disease. ABSTRACT Diaphragm dysfunction is recognized in the mdx mouse model of muscular dystrophy; however, there is a paucity of information concerning the neural control of dystrophic respiratory muscles. In young adult (8 weeks of age) male wild-type and mdx mice, we assessed ventilatory capacity, neural activation of the diaphragm and external intercostal (EIC) muscles and inspiratory pressure-generating capacity during ventilatory and non-ventilatory behaviours. We hypothesized that respiratory muscle weakness is associated with impaired peak inspiratory pressure-generating capacity in mdx mice. Ventilatory responsiveness to hypercapnic hypoxia was determined in conscious mice by whole-body plethysmography. Diaphragm isometric and isotonic contractile properties were determined ex vivo. In anaesthetized mice, thoracic oesophageal pressure, and diaphragm and EIC electromyogram (EMG) activities were recorded during baseline conditions and sustained tracheal occlusion for 30-40s. Despite substantial diaphragm weakness, mdx mice retain the capacity to enhance ventilation during hypercapnic hypoxia. Peak volume- and flow-related measures were also maintained in anaesthetized, vagotomized mdx mice. Peak inspiratory pressure was remarkably well preserved during chemoactivated breathing, augmented breaths and maximal sustained efforts during airway obstruction in mdx mice. Diaphragm and EIC EMG activities were lower during airway obstruction in mdx compared to wild-type mice. We conclude that ventilatory capacity is preserved in young mdx mice. Despite profound respiratory muscle weakness and lower diaphragm and EIC EMG activities during high demand in mdx mice, peak inspiratory pressure is preserved, revealing adequate compensation in support of respiratory system performance, at least early in dystrophic disease. We suggest that a progressive loss of compensation during advancing disease, combined with diaphragm dysfunction, underpins the development of respiratory system morbidity in dystrophic diseases.
Collapse
Affiliation(s)
- David P Burns
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Kevin H Murphy
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Eric F Lucking
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Ken D O'Halloran
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| |
Collapse
|
4
|
Effects of (−)-epicatechin on frontal cortex DAPC and dysbindin of the mdx mice. Neurosci Lett 2017; 658:142-149. [DOI: 10.1016/j.neulet.2017.08.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 07/28/2017] [Accepted: 08/23/2017] [Indexed: 11/23/2022]
|
5
|
Miranda R, Laroche S, Vaillend C. Reduced neuronal density in the CA1 anterodorsal hippocampus of the mdx mouse. Neuromuscul Disord 2016; 26:775-781. [DOI: 10.1016/j.nmd.2016.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 06/22/2016] [Accepted: 08/10/2016] [Indexed: 01/05/2023]
|
6
|
Rae MG, O'Malley D. Cognitive dysfunction in Duchenne muscular dystrophy: a possible role for neuromodulatory immune molecules. J Neurophysiol 2016; 116:1304-15. [PMID: 27385793 DOI: 10.1152/jn.00248.2016] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 06/29/2016] [Indexed: 11/22/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X chromosome-linked disease characterized by progressive physical disability, immobility, and premature death in affected boys. Underlying the devastating symptoms of DMD is the loss of dystrophin, a structural protein that connects the extracellular matrix to the cell cytoskeleton and provides protection against contraction-induced damage in muscle cells, leading to chronic peripheral inflammation. However, dystrophin is also expressed in neurons within specific brain regions, including the hippocampus, a structure associated with learning and memory formation. Linked to this, a subset of boys with DMD exhibit nonprogressing cognitive dysfunction, with deficits in verbal, short-term, and working memory. Furthermore, in the genetically comparable dystrophin-deficient mdx mouse model of DMD, some, but not all, types of learning and memory are deficient, and specific deficits in synaptogenesis and channel clustering at synapses has been noted. Little consideration has been devoted to the cognitive deficits associated with DMD compared with the research conducted into the peripheral effects of dystrophin deficiency. Therefore, this review focuses on what is known about the role of full-length dystrophin (Dp427) in hippocampal neurons. The importance of dystrophin in learning and memory is assessed, and the potential importance that inflammatory mediators, which are chronically elevated in dystrophinopathies, may have on hippocampal function is also evaluated.
Collapse
Affiliation(s)
- Mark G Rae
- Department of Physiology, University College Cork, Cork, Ireland; and
| | - Dervla O'Malley
- Department of Physiology, University College Cork, Cork, Ireland; and APC Microbiome Institute, University College Cork, Cork, Ireland
| |
Collapse
|
7
|
Hendriksen RG, Hoogland G, Schipper S, Hendriksen JG, Vles JS, Aalbers MW. A possible role of dystrophin in neuronal excitability: A review of the current literature. Neurosci Biobehav Rev 2015; 51:255-62. [DOI: 10.1016/j.neubiorev.2015.01.023] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 01/18/2015] [Accepted: 01/31/2015] [Indexed: 10/24/2022]
|
8
|
Acetylcholine, GABA and neuronal networks: a working hypothesis for compensations in the dystrophic brain. Brain Res Bull 2014; 110:1-13. [PMID: 25445612 DOI: 10.1016/j.brainresbull.2014.10.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 10/02/2014] [Accepted: 10/06/2014] [Indexed: 11/22/2022]
Abstract
Duchenne muscular dystrophy (DMD), a genetic disease arising from a mutation in the dystrophin gene, is characterized by muscle failure and is often associated with cognitive deficits. Studies of the dystrophic brain on the murine mdx model of DMD provide evidence of morphological and functional alterations in the central nervous system (CNS) possibly compatible with the cognitive impairment seen in DMD. However, while some of the alterations reported are a direct consequence of the absence of dystrophin, others seem to be associated only indirectly. In this review we reevaluate the literature in order to formulate a possible explanation for the cognitive impairments associated with DMD. We present a working hypothesis, demonstrated as an integrated neuronal network model, according to which within the cascade of events leading to cognitive impairments there are compensatory mechanisms aimed to maintain functional stability via perpetual adjustments of excitatory and inhibitory components. Such ongoing compensatory response creates continuous perturbations that disrupt neuronal functionality in terms of network efficiency. We have theorized that in this process acetylcholine and network oscillations play a central role. A better understating of these mechanisms could provide a useful diagnostic index of the disease's progression and, perhaps, the correct counterbalance of this process might help to prevent deterioration of the CNS in DMD. Furthermore, the involvement of compensatory mechanisms in the CNS could be extended beyond DMD and possibly help to clarify other physio-pathological processes of the CNS.
Collapse
|
9
|
Ghedini PC, Avellar MCW, De Lima TCM, Lima-Landman MTR, Lapa AJ, Souccar C. Quantitative changes of nicotinic receptors in the hippocampus of dystrophin-deficient mice. Brain Res 2012; 1483:96-104. [PMID: 22995368 DOI: 10.1016/j.brainres.2012.09.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/09/2012] [Accepted: 09/10/2012] [Indexed: 10/27/2022]
Abstract
Lack of dystrophin in Duchenne muscle dystrophy (DMD) and in the mutant mdx mouse results in progressive muscle degeneration, structural changes at the neuromuscular junction, and destabilization of the nicotinic acetylcholine receptors (nAChRs). One-third of DMD patients also present non-progressive cognitive impairments. Considering the role of the cholinergic system in cognitive functions, the number of nAChR binding sites and the mRNA levels of α4, β2, and α7 subunits were determined in brain regions normally enriched in dystrophin (cortex, hippocampus and cerebellum) of mdx mice using specific ligands and reverse-transcription polymerase chain reaction assays, respectively. Membrane preparations of these brain regions were obtained from male control and mdx mice at 4 and 12 months of age. The number of [³H]-cytisine (α4β2) and [¹²⁵I]-α-bungarotoxin ([¹²⁵I]-αBGT, α7) binding sites in the cortex and cerebellum was not altered with age or among age-matched control and mdx mice. A significant reduction in [³H]-cytisine (48%) and [¹²⁵I]-αBGT (37%) binding sites was detected in the hippocampus of mdx mice at 12 months of age. When compared with the age-matched control groups, the mdx mice did not have significantly altered [³H]-cytisine binding in the hippocampus, but [¹²⁵I]-αBGT binding in the same brain region was 52% higher at 4 months and 20% lower at 12 months. mRNA transcripts for the nAChR α4, β2, and α7 subunits were not significantly altered in the same brain regions of all animal groups. These results suggest a potential alteration of the nicotinic cholinergic function in the hippocampus of dystrophin-deficient mice, which might contribute to the impairments in cognitive functions, such as learning and memory, that have been reported in the dystrophic murine model and DMD patients.
Collapse
Affiliation(s)
- Paulo César Ghedini
- Department of Pharmacology, Section of Natural Products, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | | | | | | | | | | |
Collapse
|
10
|
Simões GF, de Oliveira ALR. Granulocyte-colony stimulating factor improves MDX mouse response to peripheral nerve injury. PLoS One 2012; 7:e42803. [PMID: 22912741 PMCID: PMC3418329 DOI: 10.1371/journal.pone.0042803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 07/11/2012] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND G-CSF has been shown to increase neuronal survival, which may positively influence the spinal cord microenvironment during the course of muscular dystrophies. METHODOLOGY/PRINCIPAL FINDINGS Male MDX mice that were six weeks of age received a left sciatic nerve transection and were treated with intraperitoneal injections of 200 µg/kg/day of G-CSF 7 days before and 7 days after the transection. The axotomy was performed after the cycles of muscular degeneration/regeneration, consistent with previous descriptions of this model of muscular dystrophy. C57BL/10 mice were used as control subjects. Seven days after the surgery, the animals were sacrificed and their lumbar spinal cords were processed for immunohistochemistry (anti-MHC I, anti-Synaptophysin, anti-GFAP and anti-IBA-1) and transmission electron microscopy. MHC I expression increased in both strains of mice after the axotomy. Nevertheless, the MDX mice displayed a significantly smaller MHC I upregulation than the control mice. Regarding GFAP expression, the MDX mice showed a stronger astrogliosis compared with the C57BL/10 mice across all groups. Both groups that were treated with G-CSF demonstrated preservation of synaptophysin expression compared with the untreated and placebo groups. The quantitative analysis of the ultrastructural level showed a preservation of the synaptic covering for the both groups that were treated with G-CSF and the axotomized groups showed a smaller loss of synaptic contact in relation to the treated groups after the lesion. CONCLUSIONS/SIGNIFICANCE The reduction of active inputs to the alpha-motoneurons and increased astrogliosis in the axotomized and control groups may be associated with the cycles of muscle degeneration/regeneration that occur postnatally. The G-CSF treated group showed a preservation of the spinal cord microenvironment after the lesion. Moreover, the increase of MHC I expression in the MDX mice that were treated with G-CSF may indicate that this drug performs an active role in regenerative potential after lesions.
Collapse
Affiliation(s)
- Gustavo Ferreira Simões
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | | |
Collapse
|
11
|
Lv SY, Zou QH, Cui JL, Zhao N, Hu J, Long XY, Sun YC, He J, Zhu CZ, He Y, Zang YF. Decreased gray matter concentration and local synchronization of spontaneous activity in the motor cortex in Duchenne muscular dystrophy. AJNR Am J Neuroradiol 2011; 32:2196-200. [PMID: 21960496 DOI: 10.3174/ajnr.a2718] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE Patients with DMD have demonstrated functional abnormalities in the motor-related brain areas in previous PET, MRS, and TMS studies. We applied structural MR imaging and RS-fMRI in patients with DMD for the first time, and aimed to investigate the GMC and ReHo or local synchronization of spontaneous activity in the motor cortex. MATERIALS AND METHODS Ten boys with DMD (6.4-14.0 years of age) and 15 healthy controls (7.9-15.1 years of age) underwent brain structural MR imaging and RS-fMRI scanning. GMC and local synchronization of spontaneous activity in the motor cortex were analyzed by using VBM and ReHo approaches, respectively. RESULTS Compared with healthy controls, boys with DMD showed decreased GMC in the left PSMC and decreased ReHo in the bilateral PMSC as well as in the supplementary motor area (P < .05, corrected). CONCLUSIONS The current results indicate that boys with DMD have both GMC loss and decreased local synchronization of spontaneous activity in the motor cortex, which might be due to the deficiency of dystrophin in the brain.
Collapse
Affiliation(s)
- S-Y Lv
- Department of Radiology and Neurology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Projections from the brain to the spinal cord in the mouse. Brain Struct Funct 2010; 215:159-86. [DOI: 10.1007/s00429-010-0281-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Accepted: 09/23/2010] [Indexed: 12/20/2022]
|
13
|
Minciacchi D, Del Tongo C, Carretta D, Nosi D, Granato A. Alterations of the cortico-cortical network in sensori-motor areas of dystrophin deficient mice. Neuroscience 2010; 166:1129-39. [DOI: 10.1016/j.neuroscience.2010.01.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 01/19/2010] [Accepted: 01/19/2010] [Indexed: 02/09/2023]
|
14
|
Del Tongo C, Carretta D, Fulgenzi G, Catini C, Minciacchi D. Parvalbumin-positive GABAergic interneurons are increased in the dorsal hippocampus of the dystrophic mdx mouse. Acta Neuropathol 2009; 118:803-12. [PMID: 19588159 DOI: 10.1007/s00401-009-0567-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 06/17/2009] [Accepted: 06/26/2009] [Indexed: 02/07/2023]
Abstract
Duchenne muscular dystrophy (DMD) is characterized by variable alterations of the dystrophin gene and by muscle weakness and cognitive impairment. We postulated an association between cognitive impairment and architectural changes of the hippocampal GABAergic system. We investigated a major subpopulation of GABAergic neurons, the parvalbumin-immunopositive (PV-I) cells, in the dorsal hippocampus of the mdx mouse, an acknowledged model of DMD. PV-I neurons were quantified and their distribution was compared in CA1, CA2, CA3, and dentate gyrus in wild-type and mdx mice. The cell morphology and topography of PV-I neurons were maintained. Conversely, the number of PV-I neurons was significantly increased in the mdx mouse. The percent increase of PV-I neurons was from 45% for CA2, up to 125% for the dentate gyrus. In addition, the increased parvalbumin content in the mdx hippocampus was confirmed by Western blot. A change in the hippocampus processing abilities is the expected functional counterpart of the modification displayed by PV-I GABAergic neurons. Altered hippocampal functionality can be responsible for part of the cognitive impairment in DMD.
Collapse
Affiliation(s)
- Claudia Del Tongo
- Department of Anatomy, Histology and Forensic Medicine, University of Florence, Viale Morgagni, 85, 50134 Florence, Italy.
| | | | | | | | | |
Collapse
|
15
|
Minciacchi D, Kassa RM, Del Tongo C, Mariotti R, Bentivoglio M. Voronoi-based spatial analysis reveals selective interneuron changes in the cortex of FALS mice. Exp Neurol 2009; 215:77-86. [DOI: 10.1016/j.expneurol.2008.09.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 09/01/2008] [Accepted: 09/15/2008] [Indexed: 12/13/2022]
|
16
|
Miranda R, Sebrie C, Degrouard J, Gillet B, Jaillard D, Laroche S, Vaillend C. Reorganization of Inhibitory Synapses and Increased PSD Length of Perforated Excitatory Synapses in Hippocampal Area CA1 of Dystrophin-Deficient mdx Mice. Cereb Cortex 2008; 19:876-88. [DOI: 10.1093/cercor/bhn135] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
17
|
Loss of neuronal projections in the dystrophin-deficient mdx mouse is not progressive. Brain Res 2008; 1224:127-32. [PMID: 18603229 DOI: 10.1016/j.brainres.2008.05.059] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Revised: 05/14/2008] [Accepted: 05/17/2008] [Indexed: 11/22/2022]
Abstract
Lack of dystrophin is known to reduce several cerebral fiber systems. To investigate if the loss of fibers is progressive, we analyzed projections of the trigeminal sensory system to the red nucleus in 3, 6, and 12 month old dystrophin-deficient mdx mice. The retrograde tracer fluorogold was injected in the magnocellular part of the red nucleus, and the number of labeled neurons in the oral part of the spinal trigeminal nucleus (Sp5O) was counted. We found that the number of labeled Sp5O neurons was reduced by 50% in mdx mice compared to age-matched control mice. The number of labeled Sp5O neurons did not change significantly between 3 and 12 months neither in mdx nor in control mice. In addition, the number of labeled neurons in the interstitial system of the trigeminal nerve was reduced by 43% in mdx mice. We conclude that fiber loss did not continue beyond the age of 3 months. Our data suggest that lack of full-length dystrophin impairs neuronal migration or axonal outgrowth, or increases neuronal death during fetal or early life.
Collapse
|
18
|
Pinto ML, Tokunaga HHVO, Souccar C, Schoorlemmer GHM, Lapa RDCRDS. Morphological changes in the trigemino-rubral pathway in dystrophic (mdx) mice. Neurosci Lett 2007; 416:175-9. [PMID: 17324512 DOI: 10.1016/j.neulet.2007.02.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2006] [Revised: 01/31/2007] [Accepted: 02/01/2007] [Indexed: 11/16/2022]
Abstract
The lack of dystrophin that causes Duchenne muscle disease affects not only the muscles but also the central nervous system. Dystrophin-deficient mdx mice present changes in several brain fiber systems. We compared the projections from the trigeminal sensory nuclear complex to the red nucleus in control and mdx mice using retrograde tracers. Injection of 200 nL 2% fluorogold into the red nucleus caused labeling in the mesencephalic trigeminal nucleus, the principal sensory nucleus and the oral, interpolar, and caudal subnuclei of the spinal trigeminal nucleus in both control and mdx mice. Injection of latex microbeads labeled with rhodamine and fluorescein gave results similar to those seen with fluorogold. The number of labeled neurons in the trigeminal sensory nuclear complex was significantly reduced in mdx mice. In the oral subnucleus of the spinal trigeminal nucleus this reduction was 50%. These results indicate that the trigemino-rubral pathway is reduced in dystrophin-deficient mice.
Collapse
Affiliation(s)
- Magali Luci Pinto
- Department of Histology, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | | | | | | |
Collapse
|
19
|
Bulbo-Pons-Mesencephalic Projections to the Lumbo-Sacral Spinal Cord in Healthy and Spastic Paresis-Affected Cattle: A Comparative Investigation. Vet Res Commun 2006. [DOI: 10.1007/s11259-006-0034-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
20
|
De Stefano ME, Leone L, Lombardi L, Paggi P. Lack of dystrophin leads to the selective loss of superior cervical ganglion neurons projecting to muscular targets in genetically dystrophic mdx mice. Neurobiol Dis 2005; 20:929-42. [PMID: 16023353 DOI: 10.1016/j.nbd.2005.06.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2005] [Revised: 05/26/2005] [Accepted: 06/03/2005] [Indexed: 12/31/2022] Open
Abstract
Autonomic imbalance is a pathological aspect of Duchenne muscular dystrophy. Here, we show that the sympathetic superior cervical ganglion (SCG) of mdx mice, which lack dystrophin (Dp427), has 36% fewer neurons than that of wild-type animals. Cell loss occurs around P10 and affects those neurons innervating muscular targets (heart and iris), which, differently from the submandibular gland (non-muscular target), are precociously damaged by the lack of Dp427. In addition, although we reveal altered axonal defasciculation in the submandibular gland and reduced terminal sprouting in all SCG target organs, poor adrenergic innervation is observed only in the heart and iris. These alterations, detected as early as P5, when neuronal loss has not yet occurred, suggest that in mdx mice the absence of Dp427 directly impairs the axonal growth and terminal sprouting of sympathetic neurons. However, when these intrinsic alterations combine with structural and/or functional damages of muscular targets, neuronal death occurs.
Collapse
MESH Headings
- Animals
- Autonomic Nervous System Diseases/genetics
- Autonomic Nervous System Diseases/metabolism
- Autonomic Nervous System Diseases/physiopathology
- Cell Death/genetics
- Disease Models, Animal
- Dystrophin/deficiency
- Growth Cones/metabolism
- Growth Cones/ultrastructure
- Heart/growth & development
- Heart/innervation
- Iris/growth & development
- Iris/innervation
- Iris/ultrastructure
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred mdx
- Microscopy, Electron, Transmission
- Muscle, Smooth/innervation
- Muscle, Smooth/physiopathology
- Muscles/innervation
- Muscles/ultrastructure
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Muscular Dystrophy, Duchenne/physiopathology
- Myocardium/ultrastructure
- Nerve Degeneration/genetics
- Nerve Degeneration/metabolism
- Nerve Degeneration/physiopathology
- Neuronal Plasticity/genetics
- Neurons/metabolism
- Neurons/pathology
- Superior Cervical Ganglion/metabolism
- Superior Cervical Ganglion/pathology
- Superior Cervical Ganglion/physiopathology
Collapse
Affiliation(s)
- M Egle De Stefano
- Dipartimento di Biologia Cellulare e dello Sviluppo, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy.
| | | | | | | |
Collapse
|
21
|
Carretta D, Santarelli M, Sbriccoli A, Pinto F, Catini C, Minciacchi D. Spatial analysis reveals alterations of parvalbumin- and calbindin-positive local circuit neurons in the cerebral cortex of mutant mdx mice. Brain Res 2004; 1016:1-11. [PMID: 15234246 DOI: 10.1016/j.brainres.2004.04.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2004] [Indexed: 11/21/2022]
Abstract
The aim of the present study was to investigate the spatial organization of selected populations of local circuit neurons in the cerebral cortex of the mutant mdx mouse, an acknowledged model of Duchenne Muscular Dystrophy. To this purpose, we quantified and compared the distribution of parvalbumin- and calbindin-positive neurons in the motor, somatosensory, visual, and anterior cingulate cortices of wild-type and mdx mice. The methodological approach was based on generation of two-dimensional Voronoi polygons from digital charts of the cell populations visualized immunohistochemically. Polygon areas were then analyzed and the derived coefficients of variation were statistically compared. Using this strategy, we were able to reveal, in mdx mice, changes involving both the above populations of interneurons. These changes were evident in the motor and anterior cingulate cortices but not in the somatosensory and visual cortices. In addition, the changes of coefficients of variation were area-specific in the cortex of mdx mice. The values increased in the motor cortex and decreased in the anterior cingulate cortex with respect to the corresponding values of wild-type animals. The present findings point out widespread alterations in the mdx cortex involving also areas not primarily related to sensorimotor integration. In addition, we demonstrate that cortical alterations of the local circuit machinery are characterized in mdx mice by individual regional differences.
Collapse
|
22
|
Carretta D, Santarelli M, Vanni D, Ciabatti S, Sbriccoli A, Pinto F, Minciacchi D. Cortical and brainstem neurons containing calcium-binding proteins in a murine model of Duchenne's muscular dystrophy: selective changes in the sensorimotor cortex. J Comp Neurol 2003; 456:48-59. [PMID: 12508313 DOI: 10.1002/cne.10506] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In the muscular dystrophic (mdx) mouse, which is characterized by deficient dystrophin expression and provides a model of Duchenne's muscular dystrophy, we previously demonstrated marked central nervous system alterations and in particular a quantitative reduction of corticospinal and rubrospinal neurons and pathologic changes of these cells. Prompted by these findings and in view of the relations between calcium ions and dystrophin, we analyzed with immunohistochemistry the neurons containing the calcium-binding proteins parvalbumin, calbindin D28k, and calretinin in cortical areas and brainstem nuclei of mdx mice. In the sensorimotor cortex, parvalbumin-positive and calbindin-positive neurons, which represent a subset of cortical interneurons, were significantly more numerous in mdx mice than in wild-type ones. In addition, the laminar distribution of parvalbumin-positive neurons in the motor and somatosensory cortical areas of mdx mice was altered with respect to wild-type animals. No alterations in the number and distribution were found in the parvalbumin- or calbindin-expressing cell populations of the visual and anterior cingulate cortices of mdx mice. The pattern of calretinin immunoreactivity was normal in all investigated cortical areas. The cell populations containing either calcium-binding protein were similar in brainstem nuclei of mdx and wild-type mice. The present findings demonstrated selective changes of subsets of interneurons in the motor and somatosensory cortical areas of mdx mice. Therefore, the data showed that, in the cortices of these mutant animals, the previously demonstrated pathologic changes of corticospinal cell populations are accompanied by marked alterations in the local circuitry.
Collapse
Affiliation(s)
- Donatella Carretta
- Department of Neurological and Psychiatric Sciences, University of Florence, Florence, Italy, I-50134
| | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
Duchenne muscular dystrophy (DMD) is the second most commonly occurring genetically inherited disease in humans. It is an X-linked condition that affects approximately one in 3300 live male births. It is caused by the absence or disruption of the protein dystrophin, which is found in a variety of tissues, most notably skeletal muscle and neurones in particular regions of the CNS. Clinically DMD is characterized by a severe pathology of the skeletal musculature that results in the premature death of the individual. An important aspect of DMD that has received less attention is the role played by the absence or disruption of dystrophin on CNS function. In this review we concentrate on insights into this role gained from investigation of boys with DMD and the genetically most relevant animal model of DMD, the dystrophin-deficient mdx mouse. Behavioural studies have shown that DMD boys have a cognitive impairment and a lower IQ (average 85), whilst the mdx mice display an impairment in passive avoidance reflex and in short-term memory. In DMD boys, there is evidence of disordered CNS architecture, abnormalities in dendrites and loss of neurones, all associated with neurones that normally express dystrophin. In the mdx mouse, there have been reports of a 50% decrease in neurone number and neural shrinkage in regions of the cerebral cortex and brainstem. Histological evidence shows that the density of GABA(A) channel clusters is reduced in mdx Purkinje cells and hippocampal CA1 neurones. At the biochemical level, in DMD boys the bioenergetics of the CNS is abnormal and there is an increase in the levels of choline-containing compounds, indicative of CNS pathology. The mdx mice also display abnormal bioenergetics, with an increased level of inorganic phosphate and increased levels of choline-containing compounds. Functionally, DMD boys have EEG abnormalities and there is some preliminary evidence that synaptic function is affected adversely by the absence of dystrophin. Electrophysiological studies of mdx mice have shown that hippocampal neurones have an increased susceptibility to hypoxia. These recent findings on the role of dystrophin in the CNS have implications for the clinical management of boys with DMD.
Collapse
Affiliation(s)
- J L Anderson
- School of Physiology and Pharmacology, University of New South Wales, Sydney, Australia
| | | | | | | |
Collapse
|