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Karat BG, DeKraker J, Hussain U, Köhler S, Khan AR. Mapping the macrostructure and microstructure of the in vivo human hippocampus using diffusion MRI. Hum Brain Mapp 2023; 44:5485-5503. [PMID: 37615057 PMCID: PMC10543110 DOI: 10.1002/hbm.26461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/12/2023] [Accepted: 08/06/2023] [Indexed: 08/25/2023] Open
Abstract
The hippocampus is classically divided into mesoscopic subfields which contain varying microstructure that contribute to their unique functional roles. It has been challenging to characterize this microstructure with current magnetic resonance based neuroimaging techniques. In this work, we used diffusion magnetic resonance imaging (dMRI) and a novel surface-based approach in the hippocampus which revealed distinct microstructural distributions of neurite density and dispersion, T1w/T2w ratio as a proxy for myelin content, fractional anisotropy, and mean diffusivity. We used the neurite orientation dispersion and density imaging (NODDI) model optimized for grey matter diffusivity to characterize neurite density and dispersion. We found that neurite dispersion was highest in the cornu ammonis (CA) 1 and subiculum subfields which likely captures the large heterogeneity of tangential and radial fibres, such as the Schaffer collaterals, perforant path, and pyramidal neurons. Neurite density and T1w/T2w were highest in the subiculum and CA3 and lowest in CA1, which may reflect known myeloarchitectonic differences between these subfields. Using a simple logistic regression model, we showed that neurite density, dispersion, and T1w/T2w measures were separable across the subfields, suggesting that they may be sensitive to the known variability in subfield cyto- and myeloarchitecture. We report macrostructural measures of gyrification, thickness, and curvature that were in line with ex vivo descriptions of hippocampal anatomy. We employed a multivariate orthogonal projective non-negative matrix factorization (OPNNMF) approach to capture co-varying regions of macro- and microstructure across the hippocampus. The clusters were highly variable along the medial-lateral (proximal-distal) direction, likely reflecting known differences in morphology, cytoarchitectonic profiles, and connectivity. Finally, we show that by examining the main direction of diffusion relative to canonical hippocampal axes, we could identify regions with stereotyped microstructural orientations that may map onto specific fibre pathways, such as the Schaffer collaterals, perforant path, fimbria, and alveus. These results highlight the value of combining in vivo dMRI with computational approaches for capturing hippocampal microstructure, which may provide useful features for understanding cognition and for diagnosis of disease states.
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Affiliation(s)
- Bradley G. Karat
- Robarts Research Institute, Schulich School of Medicine and DentistryUniversity of Western OntarioLondonOntarioCanada
- Neuroscience Graduate ProgramUniversity of Western OntarioLondonOntarioCanada
| | - Jordan DeKraker
- Robarts Research Institute, Schulich School of Medicine and DentistryUniversity of Western OntarioLondonOntarioCanada
- Montreal Neurological InstituteMcGill UniversityMontrealQuebecCanada
| | | | - Stefan Köhler
- Department of PsychologyUniversity of Western OntarioLondonOntarioCanada
| | - Ali R. Khan
- Robarts Research Institute, Schulich School of Medicine and DentistryUniversity of Western OntarioLondonOntarioCanada
- Western Institute for NeuroscienceUniversity of Western OntarioLondonOntarioCanada
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Matorina N, Tseng J, Ladyka-Wojcik N, Olsen R, Mabbott DJ, Barense MD. Sleep Differentially and Profoundly Impairs Recall Memory in a Patient with Fornix Damage. J Cogn Neurosci 2023; 35:1635-1655. [PMID: 37584584 DOI: 10.1162/jocn_a_02038] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
In March 2020, C.T., a kind, bright, and friendly young woman underwent surgery for a midline tumor involving her septum pellucidum and extending down into her fornices bilaterally. Following tumor diagnosis and surgery, C.T. experienced significant memory deficits: C.T.'s family reported that she could remember things throughout the day, but when she woke up in the morning or following a nap, she would expect to be in the hospital, forgetting all the information that she had learned before sleep. The current study aimed to empirically validate C.T.'s pattern of memory loss and explore its neurological underpinnings. On two successive days, C.T. and age-matched controls watched an episode of a TV show and took a nap or stayed awake before completing a memory test. Although C.T. performed numerically worse than controls in both conditions, sleep profoundly exacerbated her memory impairment, such that she could not recall any details following a nap. This effect was replicated in a second testing session. High-resolution MRI scans showed evidence of the trans-callosal surgical approach's impact on the mid-anterior corpus callosum, indicated that C.T. had perturbed white matter particularly in the right fornix column, and demonstrated that C.T.'s hippocampal volumes did not differ from controls. These findings suggest that the fornix is important for processing episodic memories during sleep. As a key output pathway of the hippocampus, the fornix may ensure that specific memories are replayed during sleep, maintain the balance of sleep stages, or allow for the retrieval of memories following sleep.
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Affiliation(s)
| | - Julie Tseng
- Neurosciences and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada
| | | | | | - Donald J Mabbott
- University of Toronto, Ontario, Canada
- Neurosciences and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Morgan D Barense
- University of Toronto, Ontario, Canada
- Rotman Research Institute, Toronto, Ontario, Canada
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Zhou Z, Zhi C, Chen D, Cai Z, Jiang X. Single-nucleus RNA sequencing reveals cell type-specific transcriptome alterations of Down syndrome hippocampus using the Dp16 mouse model. Genes Genomics 2023; 45:1305-1315. [PMID: 37548883 DOI: 10.1007/s13258-023-01433-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 07/19/2023] [Indexed: 08/08/2023]
Abstract
BACKGROUND Down syndrome (DS), the most frequently occurring human chromosomal disorder, is caused by trisomy 21. The exact molecular effects of trisomy on certain cell populations in the brain remain poorly understood. OBJECTIVE The purpose of this study was to investigate the effects of trisomy on the transcriptomes of various types of neurons and nonneuronal cells in the hippocampus. METHODS A total of 8993 nuclei from the WT and 6445 nuclei from the Dp16 hippocampus were analyzed by single-nucleus RNA sequencing (snRNA-seq). Cell clustering was achieved by the Seurat program. RESULTS Hippocampal cells were grouped into multiple neuronal and nonneuronal populations. Only a limited number of trisomic genes were upregulated (q < 0.001) over 1.25-fold in a specific type of hippocampal cell. Specifically, deregulation of genes associated with synaptic signaling and organization was observed in multiple cell populations, including excitatory neurons, oligodendrocytes, and microglia. This observation suggests the potential importance of synapse deficits in DS. Interestingly, GO annotation of the upregulated genes suggested potential activation of the immune system by hippocampal excitatory neurons. Fewer trisomic genes were altered in nonneuronal cells than in neurons. Notably, microglial transcriptome analysis revealed significantly (q < 0.001) increased expression of C1qb and C1qc, which suggested potential involvement of complement-mediated synapse loss mediated by microglia in DS. CONCLUSION The trisomy-related hippocampal deficits should be driven by a small amount, not all, of the trisomic genes in a specific type of cell. Our work may help to narrow down both the molecular and cellular targets for future gene therapies in DS.
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Affiliation(s)
- Zuolin Zhou
- The Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, 310051, Zhejiang, China
| | - Chunchun Zhi
- The Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, 310051, Zhejiang, China
| | - Die Chen
- The Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, 310051, Zhejiang, China
| | - Zhaowei Cai
- Laboratory Animal Research Center, Zhejiang Chinese Medical University, Hangzhou, 310053, Zhejiang, China
| | - Xiaoling Jiang
- The Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, 310051, Zhejiang, China.
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Rusu B, Kukreja B, Wu T, Dan SJ, Feng MY, Kalish BT. Single-Nucleus Profiling Identifies Accelerated Oligodendrocyte Precursor Cell Senescence in a Mouse Model of Down Syndrome. eNeuro 2023; 10:ENEURO.0147-23.2023. [PMID: 37491366 PMCID: PMC10449487 DOI: 10.1523/eneuro.0147-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 07/06/2023] [Accepted: 07/10/2023] [Indexed: 07/27/2023] Open
Abstract
Down syndrome (DS), the most common genetic cause of intellectual disability, is associated with lifelong cognitive deficits. However, the mechanisms by which triplication of chromosome 21 genes drive neuroinflammation and cognitive dysfunction are poorly understood. Here, using the Ts65Dn mouse model of DS, we performed an integrated single-nucleus ATAC and RNA-sequencing (snATAC-seq and snRNA-seq) analysis of the adult cortex. We identified cell type-specific transcriptional and chromatin-associated changes in the Ts65Dn cortex, including regulators of neuroinflammation, transcription and translation, myelination, and mitochondrial function. We discovered enrichment of a senescence-associated transcriptional signature in Ts65Dn oligodendrocyte (OL) precursor cells (OPCs) and epigenetic changes consistent with a loss of heterochromatin. We found that senescence is restricted to a subset of OPCs concentrated in deep cortical layers. Treatment of Ts65Dn mice with a senescence-reducing flavonoid rescued cortical OPC proliferation, restored microglial homeostasis, and improved contextual fear memory. Together, these findings suggest that cortical OPC senescence may be an important driver of neuropathology in DS.
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Affiliation(s)
- Bianca Rusu
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5G 1A8, Canada
- Program in Neuroscience and Mental Health, SickKids Research Institute, Toronto, Ontario M5G 1L7, Canada
| | - Bharti Kukreja
- Program in Neuroscience and Mental Health, SickKids Research Institute, Toronto, Ontario M5G 1L7, Canada
| | - Taiyi Wu
- Program in Neuroscience and Mental Health, SickKids Research Institute, Toronto, Ontario M5G 1L7, Canada
| | - Sophie J Dan
- Program in Neuroscience and Mental Health, SickKids Research Institute, Toronto, Ontario M5G 1L7, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario M5G 1A8, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario M5G 1A8, Canada
| | - Min Yi Feng
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5G 1A8, Canada
- Program in Neuroscience and Mental Health, SickKids Research Institute, Toronto, Ontario M5G 1L7, Canada
| | - Brian T Kalish
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5G 1A8, Canada
- Program in Neuroscience and Mental Health, SickKids Research Institute, Toronto, Ontario M5G 1L7, Canada
- Division of Neonatology, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada
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Ichimata S, Martinez-Valbuena I, Lee S, Li J, Karakani AM, Kovacs GG. Distinct Molecular Signatures of Amyloid-Beta and Tau in Alzheimer's Disease Associated with Down Syndrome. Int J Mol Sci 2023; 24:11596. [PMID: 37511361 PMCID: PMC10380583 DOI: 10.3390/ijms241411596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/11/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
Limited comparative data exist on the molecular spectrum of amyloid-beta (Aβ) and tau deposition in individuals with Down syndrome (DS) and sporadic Alzheimer's disease (sAD). We assessed Aβ and tau deposition severity in the temporal lobe and cerebellum of ten DS and ten sAD cases. Immunohistochemistry was performed using antibodies against eight different Aβ epitopes (6F/3D, Aβ38, Aβ39, Aβ40, Aβ42, Aβ43, pyroglutamate Aβ at third glutamic acid (AβNp3E), phosphorylated- (p-)Aβ at 8th serine (AβpSer8)), and six different pathological tau epitopes (p-Ser202/Thr205, p-Thr231, p-Ser396, Alz50, MC1, GT38). Findings were evaluated semi-quantitatively and quantitatively using digital pathology. DS cases had significantly higher neocortical parenchymal deposition (Aβ38, Aβ42, and AβpSer8), and cerebellar parenchymal deposition (Aβ40, Aβ42, AβNp3E, and AβpSer8) than sAD cases. Furthermore, DS cases had a significantly larger mean plaque size (6F/3D, Aβ42, AβNp3E) in the temporal lobe, and significantly greater deposition of cerebral and cerebellar Aβ42 than sAD cases in the quantitative analysis. Western blotting corroborated these findings. Regarding tau pathology, DS cases had significantly more severe cerebral tau deposition than sAD cases, especially in the white matter (p-Ser202/Thr205, p-Thr231, Alz50, and MC1). Greater total tau deposition in the white matter (p-Ser202/Thr205, p-Thr231, and Alz50) of DS cases was confirmed by quantitative analysis. Our data suggest that the Aβ and tau molecular signatures in DS are distinct from those in sAD.
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Affiliation(s)
- Shojiro Ichimata
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON M5T 2S8, Canada; (S.I.); (I.M.-V.); (S.L.); (J.L.); (A.M.K.)
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A1, Canada
- Department of Legal Medicine, Faculty of Medicine, University of Toyama, Toyama 930-8555, Japan
| | - Ivan Martinez-Valbuena
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON M5T 2S8, Canada; (S.I.); (I.M.-V.); (S.L.); (J.L.); (A.M.K.)
| | - Seojin Lee
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON M5T 2S8, Canada; (S.I.); (I.M.-V.); (S.L.); (J.L.); (A.M.K.)
| | - Jun Li
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON M5T 2S8, Canada; (S.I.); (I.M.-V.); (S.L.); (J.L.); (A.M.K.)
| | - Ali M. Karakani
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON M5T 2S8, Canada; (S.I.); (I.M.-V.); (S.L.); (J.L.); (A.M.K.)
| | - Gabor G. Kovacs
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON M5T 2S8, Canada; (S.I.); (I.M.-V.); (S.L.); (J.L.); (A.M.K.)
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A1, Canada
- Edmond J. Safra Program in Parkinson’s Disease, Rossy Program for PSP Research and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON M5T 2S8, Canada
- Laboratory Medicine Program, Krembil Brain Institute, University Health Network, Toronto, ON M5G 2C4, Canada
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Watson LA, Meharena HS. From neurodevelopment to neurodegeneration: utilizing human stem cell models to gain insight into Down syndrome. Front Genet 2023; 14:1198129. [PMID: 37323671 PMCID: PMC10267712 DOI: 10.3389/fgene.2023.1198129] [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: 03/31/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023] Open
Abstract
Down syndrome (DS), caused by triplication of chromosome 21, is the most frequent aneuploidy observed in the human population and represents the most common genetic form of intellectual disability and early-onset Alzheimer's disease (AD). Individuals with DS exhibit a wide spectrum of clinical presentation, with a number of organs implicated including the neurological, immune, musculoskeletal, cardiac, and gastrointestinal systems. Decades of DS research have illuminated our understanding of the disorder, however many of the features that limit quality of life and independence of individuals with DS, including intellectual disability and early-onset dementia, remain poorly understood. This lack of knowledge of the cellular and molecular mechanisms leading to neurological features of DS has caused significant roadblocks in developing effective therapeutic strategies to improve quality of life for individuals with DS. Recent technological advances in human stem cell culture methods, genome editing approaches, and single-cell transcriptomics have provided paradigm-shifting insights into complex neurological diseases such as DS. Here, we review novel neurological disease modeling approaches, how they have been used to study DS, and what questions might be addressed in the future using these innovative tools.
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Utrobičić DK, Karlica H, Jerončić A, Borjan I, Mudnić I. Is the prolongation latency of visual evoked potentials a pathological sign in children with Down’s syndrome without ocular abnormalities? Case–control study of children with Down’s syndrome. BMJ Open Ophthalmol 2023. [DOI: 10.1136/bmjophth-2022-001074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023] Open
Abstract
ObjectiveTo evaluate retino-cortical function in children with Down’s syndrome (DS) and no evident ocular abnormalities beyond mild refractive error, by recording visual evoked potentials (VEP) in response to pattern-reversal stimuli and comparing to those of age-matched healthy controls.Methods and analysisAll the children with DS registered at Split-Dalmatia County who met inclusion criteria of no ocular abnormalities and with refraction error between −0.5 and +2.0 D, and their age-matched healthy controls were included in the study (n=36 children, N=72 eyes, for both groups, respectively, with the same age of 9±2 years). Transient VEP was recorded and the waves with a positive peak as a response to a pattern-reversal stimulus, were analysed. The peak P100 latency, defined as the time from the stimulus onset to the main positive peak, and peak to peak amplitudes were measured.ResultsWhile P100 wave amplitudes were comparable between two groups (p=0.804), P100 latencies were from 4.3 to 28.5 ms longer in children with DS (p<0.001). Interocular latency difference between a VEP dominant and an inferior eye was pronounced in healthy (1.2 ms (0.2–4.0), but was almost diminished in children with DS (0.3 ms (0.1–0.5), p<0.001).ConclusionOur study has demonstrated that VEP response is divergent in children with DS compared with their age-matched healthy controls, indicating possible structural or functional abnormalities of the visual cortex. As VEP results are helpful in the diagnosis and treatment planning of vision-related disorders, we should reconsider the use of common VEP diagnostic criteria in subpopulation of children with DS.
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Campbell NB, Patel Y, Moore TL, Medalla M, Zeldich E. Extracellular Vesicle Treatment Alleviates Neurodevelopmental and Neurodegenerative Pathology in Cortical Spheroid Model of Down Syndrome. Int J Mol Sci 2023; 24:3477. [PMID: 36834891 PMCID: PMC9960302 DOI: 10.3390/ijms24043477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/27/2023] [Accepted: 02/01/2023] [Indexed: 02/12/2023] Open
Abstract
Down syndrome (DS), or trisomy 21, is manifested in a variety of anatomical and cellular abnormalities resulting in intellectual deficits and early onset of Alzheimer's disease (AD) with no effective treatments available to alleviate the pathologies associated with the disorder. The therapeutic potential of extracellular vesicles (EVs) has emerged recently in relation to various neurological conditions. We have previously demonstrated the therapeutic efficacy of mesenchymal stromal cell-derived EVs (MSC-EVs) in cellular and functional recovery in a rhesus monkey model of cortical injury. In the current study, we evaluated the therapeutic effect of MSC-EVs in a cortical spheroid (CS) model of DS generated from patient-derived induced pluripotent stem cells (iPSCs). Compared to euploid controls, trisomic CS display smaller size, deficient neurogenesis, and AD-related pathological features, such as enhanced cell death and depositions of amyloid beta (Aβ) and hyperphosphorylated tau (p-tau). EV-treated trisomic CS demonstrated preserved size, partial rescue in the production of neurons, significantly decreased levels of Aβ and p-tau, and a reduction in the extent of cell death as compared to the untreated trisomic CS. Together, these results show the efficacy of EVs in mitigating DS and AD-related cellular phenotypes and pathological depositions in human CS.
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Affiliation(s)
- Natalie Baker Campbell
- Department of Anatomy & Neurobiology, Boston University Chobanian & Avedesian School of Medicine, Boston University, Boston, MA 02118, USA
| | - Yesha Patel
- Commonwealth Honors College, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Tara L. Moore
- Department of Anatomy & Neurobiology, Boston University Chobanian & Avedesian School of Medicine, Boston University, Boston, MA 02118, USA
- Center for Systems Neuroscience, Boston University, Boston, MA 02115, USA
| | - Maria Medalla
- Department of Anatomy & Neurobiology, Boston University Chobanian & Avedesian School of Medicine, Boston University, Boston, MA 02118, USA
- Center for Systems Neuroscience, Boston University, Boston, MA 02115, USA
| | - Ella Zeldich
- Department of Anatomy & Neurobiology, Boston University Chobanian & Avedesian School of Medicine, Boston University, Boston, MA 02118, USA
- Center for Systems Neuroscience, Boston University, Boston, MA 02115, USA
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Ábrahám H, Kojima H, Götzer K, Molnár A, Tornóczky T, Seress L. Development of parvalbumin-immunoreactive neurons in the postnatal human hippocampal formation. Front Neuroanat 2023; 17:1058370. [PMID: 36816519 PMCID: PMC9932602 DOI: 10.3389/fnana.2023.1058370] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 01/04/2023] [Indexed: 02/05/2023] Open
Abstract
Introduction: Parvalbumin (PV) is a calcium-binding protein present in fast-spiking GABAergic neurons, such as basket and axo-axonic cells. Previous studies in non-human primates reported prenatal expression of PV in the temporal archicortex including entorhinal cortex and hippocampal formation. In contrast, PV-immunoreactivity was observed only postnatally in the human entorhinal cortex. Regarding PV expression in the human hippocampal formation, no information is available. Methods: In this study, the neurochemical maturation of PV-immunoreactive interneurons was studied in the postnatal developing human hippocampal formation. Results: Before birth, no PV-immunoreactive neurons could be detected in the human hippocampus. At birth, only a few PV-immunoreactive neurons were visible in Ammon's horn. The first PV-immunoreactive cells in the hilus of the dentate gyrus appeared at the age of 1 month. Even at the age of 5 months, only a few PV-immunopositive cells were present in the dentate hilus. The number of cells and their dendritic and axonal arborization in Ammon's horn and in the dentate gyrus gradually increased with age. Even at the age of 2 years, dendritic tree and axons of PV-immunoreactive neurons were less complex than can be seen in 8 and 11 years old children. Discussion: Our results showed that long-lasting maturation of PV-immunoreactive interneurons follows the developmental sequence of the subfields of the human hippocampal formation and provides further morphological evidence for the long-lasting functional maturation of the human cortex.
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Affiliation(s)
- Hajnalka Ábrahám
- Department of Medical Biology and Central Electron Microscopic Laboratory, University of Pécs Medical School, Pécs, Hungary,Center for Neuroscience, University of Pécs, Pécs, Hungary,Institute for the Psychology of Special Needs, Bárczi Gusztáv Faculty of Special Needs Education, Eötvös Loránd University, Budapest, Hungary,*Correspondence: Hajnalka Ábrahám
| | - Hisae Kojima
- Department of Medical Biology and Central Electron Microscopic Laboratory, University of Pécs Medical School, Pécs, Hungary
| | - Katalin Götzer
- Department of Medical Biology and Central Electron Microscopic Laboratory, University of Pécs Medical School, Pécs, Hungary
| | - Abigél Molnár
- Department of Medical Biology and Central Electron Microscopic Laboratory, University of Pécs Medical School, Pécs, Hungary
| | - Tamás Tornóczky
- Department of Pathology, University of Pécs Medical School, Pécs, Hungary
| | - László Seress
- Department of Medical Biology and Central Electron Microscopic Laboratory, University of Pécs Medical School, Pécs, Hungary,Center for Neuroscience, University of Pécs, Pécs, Hungary
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Farley SJ, Grishok A, Zeldich E. Shaking up the silence: consequences of HMGN1 antagonizing PRC2 in the Down syndrome brain. Epigenetics Chromatin 2022; 15:39. [PMID: 36463299 PMCID: PMC9719135 DOI: 10.1186/s13072-022-00471-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 11/11/2022] [Indexed: 12/04/2022] Open
Abstract
Intellectual disability is a well-known hallmark of Down Syndrome (DS) that results from the triplication of the critical region of human chromosome 21 (HSA21). Major studies were conducted in recent years to gain an understanding about the contribution of individual triplicated genes to DS-related brain pathology. Global transcriptomic alterations and widespread changes in the establishment of neural lineages, as well as their differentiation and functional maturity, suggest genome-wide chromatin organization alterations in trisomy. High Mobility Group Nucleosome Binding Domain 1 (HMGN1), expressed from HSA21, is a chromatin remodeling protein that facilitates chromatin decompaction and is associated with acetylated lysine 27 on histone H3 (H3K27ac), a mark correlated with active transcription. Recent studies causatively linked overexpression of HMGN1 in trisomy and the development of DS-associated B cell acute lymphoblastic leukemia (B-ALL). HMGN1 has been shown to antagonize the activity of the Polycomb Repressive Complex 2 (PRC2) and prevent the deposition of histone H3 lysine 27 trimethylation mark (H3K27me3), which is associated with transcriptional repression and gene silencing. However, the possible ramifications of the increased levels of HMGN1 through the derepression of PRC2 target genes on brain cell pathology have not gained attention. In this review, we discuss the functional significance of HMGN1 in brain development and summarize accumulating reports about the essential role of PRC2 in the development of the neural system. Mechanistic understanding of how overexpression of HMGN1 may contribute to aberrant brain cell phenotypes in DS, such as altered proliferation of neural progenitors, abnormal cortical architecture, diminished myelination, neurodegeneration, and Alzheimer's disease-related pathology in trisomy 21, will facilitate the development of DS therapeutic approaches targeting chromatin.
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Affiliation(s)
- Sean J. Farley
- grid.189504.10000 0004 1936 7558Department of Anatomy and Neurobiology, Boston University Chobanian & Avedisian School of Medicine, Boston, MA USA
| | - Alla Grishok
- grid.189504.10000 0004 1936 7558Department of Biochemistry, Boston University Chobanian & Avedisian School of Medicine, Boston, MA USA ,grid.189504.10000 0004 1936 7558Boston University Genome Science Institute, Boston University Chobanian & Avedisian School of Medicine, Boston, MA USA
| | - Ella Zeldich
- Department of Anatomy and Neurobiology, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA.
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Bartesaghi R. Brain circuit pathology in Down syndrome: from neurons to neural networks. Rev Neurosci 2022; 34:365-423. [PMID: 36170842 DOI: 10.1515/revneuro-2022-0067] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/28/2022] [Indexed: 11/15/2022]
Abstract
Down syndrome (DS), a genetic pathology caused by triplication of chromosome 21, is characterized by brain hypotrophy and impairment of cognition starting from infancy. While studies in mouse models of DS have elucidated the major neuroanatomical and neurochemical defects of DS, comparatively fewer investigations have focused on the electrophysiology of the DS brain. Electrical activity is at the basis of brain functioning. Therefore, knowledge of the way in which brain circuits operate in DS is fundamental to understand the causes of behavioral impairment and devise targeted interventions. This review summarizes the state of the art regarding the electrical properties of the DS brain, starting from individual neurons and culminating in signal processing in whole neuronal networks. The reported evidence derives from mouse models of DS and from brain tissues and neurons derived from individuals with DS. EEG data recorded in individuals with DS are also provided as a key tool to understand the impact of brain circuit alterations on global brain activity.
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Affiliation(s)
- Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
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Li Z, Klein JA, Rampam S, Kurzion R, Campbell NB, Patel Y, Haydar TF, Zeldich E. Asynchronous excitatory neuron development in an isogenic cortical spheroid model of Down syndrome. Front Neurosci 2022; 16:932384. [PMID: 36161168 PMCID: PMC9504873 DOI: 10.3389/fnins.2022.932384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/21/2022] [Indexed: 11/17/2022] Open
Abstract
The intellectual disability (ID) in Down syndrome (DS) is thought to result from a variety of developmental deficits such as alterations in neural progenitor division, neurogenesis, gliogenesis, cortical architecture, and reduced cortical volume. However, the molecular processes underlying these neurodevelopmental changes are still elusive, preventing an understanding of the mechanistic basis of ID in DS. In this study, we used a pair of isogenic (trisomic and euploid) induced pluripotent stem cell (iPSC) lines to generate cortical spheroids (CS) that model the impact of trisomy 21 on brain development. Cortical spheroids contain neurons, astrocytes, and oligodendrocytes and they are widely used to approximate early neurodevelopment. Using single cell RNA sequencing (scRNA-seq), we uncovered cell type-specific transcriptomic changes in the trisomic CS. In particular, we found that excitatory neuron populations were most affected and that a specific population of cells with a transcriptomic profile resembling layer IV cortical neurons displayed the most profound divergence in developmental trajectory between trisomic and euploid genotypes. We also identified candidate genes potentially driving the developmental asynchrony between trisomic and euploid excitatory neurons. Direct comparison between the current isogenic CS scRNA-seq data and previously published datasets revealed several recurring differentially expressed genes between DS and control samples. Altogether, our study highlights the power and importance of cell type-specific analyses within a defined genetic background, coupled with broader examination of mixed samples, to comprehensively evaluate cellular phenotypes in the context of DS.
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Affiliation(s)
- Zhen Li
- Center for Neuroscience Research, Children’s National Hospital, Washington, DC, United States
| | - Jenny A. Klein
- Center for Neuroscience Research, Children’s National Hospital, Washington, DC, United States
- Graduate Program for Neuroscience, Boston University, Boston, MA, United States
| | - Sanjeev Rampam
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
| | - Ronni Kurzion
- Department of Chemistry, Boston University, Boston, MA, United States
| | | | - Yesha Patel
- Department of Anatomy and Neurobiology, Boston University, Boston, MA, United States
- Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst, MA, United States
| | - Tarik F. Haydar
- Center for Neuroscience Research, Children’s National Hospital, Washington, DC, United States
| | - Ella Zeldich
- Department of Anatomy and Neurobiology, Boston University, Boston, MA, United States
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13
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Klein JA, Haydar TF. Neurodevelopment in Down syndrome: Concordance in humans and models. Front Cell Neurosci 2022; 16:941855. [PMID: 35910249 PMCID: PMC9334873 DOI: 10.3389/fncel.2022.941855] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
Great strides have been made over the past 30 years in understanding the neurodevelopmental changes underlying the intellectual disability (ID) in Down syndrome (DS). Detailed studies of human tissue coupled with findings from rodent and induced pluripotent stem cells (iPSCs) model systems have uncovered the changes in neurogenesis, synaptic connectivity, and myelination that drive the anatomical and physiological changes resulting in the disability. However, there remain significant conflicting data between human studies and the models. To fully understand the development of ID in DS, these inconsistencies need to be reconciled. Here, we review the well documented neurodevelopmental phenotypes found in individuals with DS and examine the degree to which widely used models recapitulate these phenotypes. Resolving these areas of discord will further research on the molecular underpinnings and identify potential treatments to improve the independence and quality of life of people with DS.
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Affiliation(s)
- Jenny A. Klein
- Graduate Program for Neuroscience, Boston University, Boston, MA, United States
| | - Tarik F. Haydar
- Children’s National Hospital, Center for Neuroscience Research, Washington, DC, United States
- Departments of Pediatrics, Physiology and Pharmacology, School of Medicine and Health Sciences, George Washington University, Washington, DC, United States
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14
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Fatty Acids: A Safe Tool for Improving Neurodevelopmental Alterations in Down Syndrome? Nutrients 2022; 14:nu14142880. [PMID: 35889838 PMCID: PMC9323400 DOI: 10.3390/nu14142880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 02/06/2023] Open
Abstract
The triplication of chromosome 21 causes Down syndrome (DS), a genetic disorder that is characterized by intellectual disability (ID). The causes of ID start in utero, leading to impairments in neurogenesis, and continue into infancy, leading to impairments in dendritogenesis, spinogenesis, and connectivity. These defects are associated with alterations in mitochondrial and metabolic functions and precocious aging, leading to the early development of Alzheimer’s disease. Intense efforts are currently underway, taking advantage of DS mouse models to discover pharmacotherapies for the neurodevelopmental and cognitive deficits of DS. Many treatments that proved effective in mouse models may raise safety concerns over human use, especially at early life stages. Accumulating evidence shows that fatty acids, which are nutrients present in normal diets, exert numerous positive effects on the brain. Here, we review (i) the knowledge obtained from animal models regarding the effects of fatty acids on the brain, by focusing on alterations that are particularly prominent in DS, and (ii) the progress recently made in a DS mouse model, suggesting that fatty acids may indeed represent a useful treatment for DS. This scenario should prompt the scientific community to further explore the potential benefit of fatty acids for people with DS.
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15
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Stagni F, Bartesaghi R. The Challenging Pathway of Treatment for Neurogenesis Impairment in Down Syndrome: Achievements and Perspectives. Front Cell Neurosci 2022; 16:903729. [PMID: 35634470 PMCID: PMC9130961 DOI: 10.3389/fncel.2022.903729] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 04/19/2022] [Indexed: 12/17/2022] Open
Abstract
Down syndrome (DS), also known as trisomy 21, is a genetic disorder caused by triplication of Chromosome 21. Gene triplication may compromise different body functions but invariably impairs intellectual abilities starting from infancy. Moreover, after the fourth decade of life people with DS are likely to develop Alzheimer’s disease. Neurogenesis impairment during fetal life stages and dendritic pathology emerging in early infancy are thought to be key determinants of alterations in brain functioning in DS. Although the progressive improvement in medical care has led to a notable increase in life expectancy for people with DS, there are currently no treatments for intellectual disability. Increasing evidence in mouse models of DS reveals that pharmacological interventions in the embryonic and neonatal periods may greatly benefit brain development and cognitive performance. The most striking results have been obtained with pharmacotherapies during embryonic life stages, indicating that it is possible to pharmacologically rescue the severe neurodevelopmental defects linked to the trisomic condition. These findings provide hope that similar benefits may be possible for people with DS. This review summarizes current knowledge regarding (i) the scope and timeline of neurogenesis (and dendritic) alterations in DS, in order to delineate suitable windows for treatment; (ii) the role of triplicated genes that are most likely to be the key determinants of these alterations, in order to highlight possible therapeutic targets; and (iii) prenatal and neonatal treatments that have proved to be effective in mouse models, in order to rationalize the choice of treatment for human application. Based on this body of evidence we will discuss prospects and challenges for fetal therapy in individuals with DS as a potential means of drastically counteracting the deleterious effects of gene triplication.
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Affiliation(s)
- Fiorenza Stagni
- Department for Life Quality Studies, University of Bologna, Rimini, Italy
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- *Correspondence: Renata Bartesaghi,
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16
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Bartesaghi R, Vicari S, Mobley WC. Prenatal and Postnatal Pharmacotherapy in Down Syndrome: The Search to Prevent or Ameliorate Neurodevelopmental and Neurodegenerative Disorders. Annu Rev Pharmacol Toxicol 2022; 62:211-233. [PMID: 34990205 PMCID: PMC9632639 DOI: 10.1146/annurev-pharmtox-041521-103641] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Those with Down syndrome (DS)-trisomy for chromosome 21-are routinely impacted by cognitive dysfunction and behavioral challenges in children and adults and Alzheimer's disease in older adults. No proven treatments specifically address these cognitive or behavioral changes. However, advances in the establishment of rodent models and human cell models promise to support development of such treatments. A research agenda that emphasizes the identification of overexpressed genes that contribute demonstrably to abnormalities in cognition and behavior in model systems constitutes a rational next step. Normalizing expression of such genes may usher in an era of successful treatments applicable across the life span for those with DS.
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Affiliation(s)
- Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Stefano Vicari
- Department of Life Sciences and Public Health, Catholic University of the Sacred Heart, 00168 Rome, Italy,Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00165-00146 Rome, Italy
| | - William C. Mobley
- Department of Neurosciences, University of California, San Diego, La Jolla, California 92093, USA
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17
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Moreno DG, Utagawa EC, Arva NC, Schafernak KT, Mufson EJ, Perez SE. Postnatal Cytoarchitecture and Neurochemical Hippocampal Dysfunction in Down Syndrome. J Clin Med 2021; 10:jcm10153414. [PMID: 34362198 PMCID: PMC8347520 DOI: 10.3390/jcm10153414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 07/27/2021] [Accepted: 07/29/2021] [Indexed: 12/11/2022] Open
Abstract
Although the prenatal hippocampus displays deficits in cellular proliferation/migration and volume, which are later associated with memory deficits, little is known about the effects of trisomy 21 on postnatal hippocampal cellular development in Down syndrome (DS). We examined postnatal hippocampal neuronal profiles from autopsies of DS and neurotypical (NTD) neonates born at 38-weeks’-gestation up to children 3 years of age using antibodies against non-phosphorylated (SMI-32) and phosphorylated (SMI-34) neurofilament, calbindin D-28k (Calb), calretinin (Calr), parvalbumin (Parv), doublecortin (DCX) and Ki-67, as well as amyloid precursor protein (APP), amyloid beta (Aβ) and phosphorylated tau (p-tau). Although the distribution of SMI-32-immunoreactive (-ir) hippocampal neurons was similar at all ages in both groups, pyramidal cell apical and basal dendrites were intensely stained in NTD cases. A greater reduction in the number of DCX-ir cells was observed in the hippocampal granule cell layer in DS. Although the distribution of Calb-ir neurons was similar between the youngest and oldest NTD and DS cases, Parv-ir was not detected. Conversely, Calr-ir cells and fibers were observed at all ages in DS, while NTD cases displayed mainly Calr-ir fibers. Hippocampal APP/Aβ-ir diffuse-like plaques were seen in DS and NTD. By contrast, no Aβ1–42 or p-tau profiles were observed. These findings suggest that deficits in hippocampal neurogenesis and pyramidal cell maturation and increased Calr immunoreactivity during early postnatal life contribute to cognitive impairment in DS.
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Affiliation(s)
- David G. Moreno
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (D.G.M.); (E.C.U.); (E.J.M.)
| | - Emma C. Utagawa
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (D.G.M.); (E.C.U.); (E.J.M.)
| | - Nicoleta C. Arva
- Department of Pathology and Laboratory Medicine, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 60611, USA;
| | - Kristian T. Schafernak
- Department of Pathology and Laboratory Medicine, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA;
| | - Elliott J. Mufson
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (D.G.M.); (E.C.U.); (E.J.M.)
| | - Sylvia E. Perez
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (D.G.M.); (E.C.U.); (E.J.M.)
- Correspondence: ; Tel.: +6-02-406-3342
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18
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Liaci C, Camera M, Caslini G, Rando S, Contino S, Romano V, Merlo GR. Neuronal Cytoskeleton in Intellectual Disability: From Systems Biology and Modeling to Therapeutic Opportunities. Int J Mol Sci 2021; 22:ijms22116167. [PMID: 34200511 PMCID: PMC8201358 DOI: 10.3390/ijms22116167] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/25/2021] [Accepted: 06/04/2021] [Indexed: 02/06/2023] Open
Abstract
Intellectual disability (ID) is a pathological condition characterized by limited intellectual functioning and adaptive behaviors. It affects 1–3% of the worldwide population, and no pharmacological therapies are currently available. More than 1000 genes have been found mutated in ID patients pointing out that, despite the common phenotype, the genetic bases are highly heterogeneous and apparently unrelated. Bibliomic analysis reveals that ID genes converge onto a few biological modules, including cytoskeleton dynamics, whose regulation depends on Rho GTPases transduction. Genetic variants exert their effects at different levels in a hierarchical arrangement, starting from the molecular level and moving toward higher levels of organization, i.e., cell compartment and functions, circuits, cognition, and behavior. Thus, cytoskeleton alterations that have an impact on cell processes such as neuronal migration, neuritogenesis, and synaptic plasticity rebound on the overall establishment of an effective network and consequently on the cognitive phenotype. Systems biology (SB) approaches are more focused on the overall interconnected network rather than on individual genes, thus encouraging the design of therapies that aim to correct common dysregulated biological processes. This review summarizes current knowledge about cytoskeleton control in neurons and its relevance for the ID pathogenesis, exploiting in silico modeling and translating the implications of those findings into biomedical research.
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Affiliation(s)
- Carla Liaci
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Mattia Camera
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Giovanni Caslini
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Simona Rando
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Salvatore Contino
- Department of Engineering, University of Palermo, Viale delle Scienze Ed. 8, 90128 Palermo, Italy;
| | - Valentino Romano
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze Ed. 16, 90128 Palermo, Italy;
| | - Giorgio R. Merlo
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
- Correspondence: ; Tel.: +39-0116706449; Fax: +39-0116706432
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19
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Koenig KA, Oh SH, Stasko MR, Roth EC, Taylor HG, Ruedrich S, Wang ZI, Leverenz JB, Costa ACS. High resolution structural and functional MRI of the hippocampus in young adults with Down syndrome. Brain Commun 2021; 3:fcab088. [PMID: 33977271 PMCID: PMC8100000 DOI: 10.1093/braincomms/fcab088] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 02/19/2021] [Accepted: 03/22/2021] [Indexed: 11/29/2022] Open
Abstract
Down syndrome is the phenotypic consequence of trisomy 21, with clinical presentation including both neurodevelopmental and neurodegenerative components. Although the intellectual disability typically displayed by individuals with Down syndrome is generally global, it also involves disproportionate deficits in hippocampally-mediated cognitive processes. Hippocampal dysfunction may also relate to Alzheimer’s disease-type pathology, which can appear in as early as the first decade of life and becomes universal by age 40. Using 7-tesla MRI of the brain, we present an assessment of the structure and function of the hippocampus in 34 individuals with Down syndrome (mean age 24.5 years ± 6.5) and 27 age- and sex-matched typically developing healthy controls. In addition to increased whole-brain mean cortical thickness and lateral ventricle volumes (P < 1.0 × 10−4), individuals with Down syndrome showed selective volume reductions in bilateral hippocampal subfields cornu Ammonis field 1, dentate gyrus, and tail (P < 0.005). In the group with Down syndrome, bilateral hippocampi showed widespread reductions in the strength of functional connectivity, predominately to frontal regions (P < 0.02). Age was not related to hippocampal volumes or functional connectivity measures in either group, but both groups showed similar relationships of age to whole-brain volume measures (P < 0.05). Finally, we performed an exploratory analysis of a subgroup of individuals with Down syndrome with both imaging and neuropsychological assessments. This analysis indicated that measures of spatial memory were related to mean cortical thickness, total grey matter volume and right hemisphere hippocampal subfield volumes (P < 0.02). This work provides a first demonstration of the usefulness of high-field MRI to detect subtle differences in structure and function of the hippocampus in individuals with Down syndrome, and suggests the potential for development of MRI-derived measures as surrogate markers of drug efficacy in pharmacological studies designed to investigate enhancement of cognitive function.
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Affiliation(s)
- Katherine A Koenig
- Imaging Sciences, Imaging Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Se-Hong Oh
- Imaging Sciences, Imaging Institute, Cleveland Clinic, Cleveland, OH 44195, USA.,Department of Biomedical Engineering, Hankuk University of Foreign Studies, Yongin 449-791, Republic of Korea
| | - Melissa R Stasko
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Elizabeth C Roth
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106, USA
| | - H Gerry Taylor
- Abigail Wexner Research Institute at Nationwide Children's Hospital, and Department of Pediatrics, The Ohio State University, Columbus, OH 43215, USA
| | - Stephen Ruedrich
- Department of Psychiatry, University Hospitals, Cleveland, OH 44106, USA
| | - Z Irene Wang
- Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - James B Leverenz
- Lou Ruvo Center for Brain Health, Neurological Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Alberto C S Costa
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106, USA.,Department of Psychiatry, University Hospitals, Cleveland, OH 44106, USA
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20
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Szu J, Wojcinski A, Jiang P, Kesari S. Impact of the Olig Family on Neurodevelopmental Disorders. Front Neurosci 2021; 15:659601. [PMID: 33859549 PMCID: PMC8042229 DOI: 10.3389/fnins.2021.659601] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 03/08/2021] [Indexed: 12/13/2022] Open
Abstract
The Olig genes encode members of the basic helix-loop-helix (bHLH) family of transcription factors. Olig1, Olig2, and Olig3 are expressed in both the developing and mature central nervous system (CNS) and strictly regulate cellular specification and differentiation. Extensive studies have established functional roles of Olig1 and Olig2 in directing neuronal and glial formation during different stages in development. Recently, Olig2 overexpression was implicated in neurodevelopmental disorders down syndrome (DS) and autism spectrum disorder (ASD) but its influence on cognitive and intellectual defects remains unknown. In this review, we summarize the biological functions of the Olig family and how it uniquely promotes cellular diversity in the CNS. This is followed up with a discussion on how abnormal Olig2 expression impacts brain development and function in DS and ASD. Collectively, the studies described here emphasize vital features of the Olig members and their distinctive potential roles in neurodevelopmental disease states.
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Affiliation(s)
- Jenny Szu
- Department of Translational Neurosciences and Neurotherapeutics, Saint John's Cancer Institute, Providence Saint John's Health Center, Santa Monica, CA, United States
| | - Alexandre Wojcinski
- Department of Translational Neurosciences and Neurotherapeutics, Saint John's Cancer Institute, Providence Saint John's Health Center, Santa Monica, CA, United States
| | - Peng Jiang
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, United States
| | - Santosh Kesari
- Department of Translational Neurosciences and Neurotherapeutics, Saint John's Cancer Institute, Providence Saint John's Health Center, Santa Monica, CA, United States.,Pacific Neuroscience Institute, Providence Saint John's Health Center, Santa Monica, CA, United States
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21
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Reiche L, Göttle P, Lane L, Duek P, Park M, Azim K, Schütte J, Manousi A, Schira-Heinen J, Küry P. C21orf91 Regulates Oligodendroglial Precursor Cell Fate-A Switch in the Glial Lineage? Front Cell Neurosci 2021; 15:653075. [PMID: 33796011 PMCID: PMC8008080 DOI: 10.3389/fncel.2021.653075] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/22/2021] [Indexed: 12/16/2022] Open
Abstract
Neuropathological diseases of the central nervous system (CNS) are frequently associated with impaired differentiation of the oligodendroglial cell lineage and subsequent alterations in white matter structure and dynamics. Down syndrome (DS), or trisomy 21, is the most common genetic cause for cognitive impairments and intellectual disability (ID) and is associated with a reduction in the number of neurons and oligodendrocytes, as well as with hypomyelination and astrogliosis. Recent studies mainly focused on neuronal development in DS and underestimated the role of glial cells as pathogenic players. This also relates to C21ORF91, a protein considered a key modulator of aberrant CNS development in DS. We investigated the role of C21orf91 ortholog in terms of oligodendrogenesis and myelination using database information as well as through cultured primary oligodendroglial precursor cells (OPCs). Upon modulation of C21orf91 gene expression, we found this factor to be important for accurate oligodendroglial differentiation, influencing their capacity to mature and to myelinate axons. Interestingly, C21orf91 overexpression initiates a cell population coexpressing astroglial- and oligodendroglial markers indicating that elevated C21orf91 expression levels induce a gliogenic shift towards the astrocytic lineage reflecting non-equilibrated glial cell populations in DS brains.
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Affiliation(s)
- Laura Reiche
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Peter Göttle
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Lydie Lane
- CALIPHO Group, SIB Swiss Institute of Bioinformatics, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Paula Duek
- CALIPHO Group, SIB Swiss Institute of Bioinformatics, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Mina Park
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Kasum Azim
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Jana Schütte
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Anastasia Manousi
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Jessica Schira-Heinen
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Patrick Küry
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
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22
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Klein JA, Li Z, Rampam S, Cardini J, Ayoub A, Shaw P, Rachubinski AL, Espinosa JM, Zeldich E, Haydar TF. Sonic Hedgehog Pathway Modulation Normalizes Expression of Olig2 in Rostrally Patterned NPCs With Trisomy 21. Front Cell Neurosci 2021; 15:794675. [PMID: 35058753 PMCID: PMC8763807 DOI: 10.3389/fncel.2021.794675] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/08/2021] [Indexed: 12/14/2022] Open
Abstract
The intellectual disability found in people with Down syndrome is associated with numerous changes in early brain development, including the proliferation and differentiation of neural progenitor cells (NPCs) and the formation and maintenance of myelin in the brain. To study how early neural precursors are affected by trisomy 21, we differentiated two isogenic lines of induced pluripotent stem cells derived from people with Down syndrome into brain-like and spinal cord-like NPCs and promoted a transition towards oligodendroglial fate by activating the Sonic hedgehog (SHH) pathway. In the spinal cord-like trisomic cells, we found no difference in expression of OLIG2 or NKX2.2, two transcription factors essential for commitment to the oligodendrocyte lineage. However, in the brain-like trisomic NPCs, OLIG2 is significantly upregulated and is associated with reduced expression of NKX2.2. We found that this gene dysregulation and block in NPC transition can be normalized by increasing the concentration of a SHH pathway agonist (SAG) during differentiation. These results underscore the importance of regional and cell type differences in gene expression in Down syndrome and demonstrate that modulation of SHH signaling in trisomic cells can rescue an early perturbed step in neural lineage specification.
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Affiliation(s)
- Jenny A. Klein
- Graduate Program for Neuroscience, Boston University, Boston, MA, United States
- Department of Anatomy and Neurobiology, Boston University, Boston, MA, United States
| | - Zhen Li
- Children’s National Medical Center, Center for Neuroscience Research, Washington, DC, United States
| | - Sanjeev Rampam
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
| | - Jack Cardini
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
| | - Amara Ayoub
- Children’s National Medical Center, Center for Neuroscience Research, Washington, DC, United States
| | - Patricia Shaw
- Graduate Program for Neuroscience, Boston University, Boston, MA, United States
| | - Angela L. Rachubinski
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Joaquin M. Espinosa
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pharmocology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Ella Zeldich
- Department of Anatomy and Neurobiology, Boston University, Boston, MA, United States
- *Correspondence: Tarik F. Haydar Ella Zeldich
| | - Tarik F. Haydar
- Children’s National Medical Center, Center for Neuroscience Research, Washington, DC, United States
- *Correspondence: Tarik F. Haydar Ella Zeldich
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23
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Guedj F, Siegel AE, Pennings JLA, Alsebaa F, Massingham LJ, Tantravahi U, Bianchi DW. Apigenin as a Candidate Prenatal Treatment for Trisomy 21: Effects in Human Amniocytes and the Ts1Cje Mouse Model. Am J Hum Genet 2020; 107:911-931. [PMID: 33098770 DOI: 10.1016/j.ajhg.2020.10.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 10/05/2020] [Indexed: 12/15/2022] Open
Abstract
Human fetuses with trisomy 21 (T21) have atypical brain development that is apparent sonographically in the second trimester. We hypothesize that by analyzing and integrating dysregulated gene expression and pathways common to humans with Down syndrome (DS) and mouse models we can discover novel targets for prenatal therapy. Here, we tested the safety and efficacy of apigenin, identified with this approach, in both human amniocytes from fetuses with T21 and in the Ts1Cje mouse model. In vitro, T21 cells cultured with apigenin had significantly reduced oxidative stress and improved antioxidant defense response. In vivo, apigenin treatment mixed with chow was administered prenatally to the dams and fed to the pups over their lifetimes. There was no significant increase in birth defects or pup deaths resulting from prenatal apigenin treatment. Apigenin significantly improved several developmental milestones and spatial olfactory memory in Ts1Cje neonates. In addition, we noted sex-specific effects on exploratory behavior and long-term hippocampal memory in adult mice, and males showed significantly more improvement than females. We demonstrated that the therapeutic effects of apigenin are pleiotropic, resulting in decreased oxidative stress, activation of pro-proliferative and pro-neurogenic genes (KI67, Nestin, Sox2, and PAX6), reduction of the pro-inflammatory cytokines INFG, IL1A, and IL12P70 through the inhibition of NFκB signaling, increase of the anti-inflammatory cytokines IL10 and IL12P40, and increased expression of the angiogenic and neurotrophic factors VEGFA and IL7. These studies provide proof of principle that apigenin has multiple therapeutic targets in preclinical models of DS.
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Affiliation(s)
- Faycal Guedj
- Prenatal Genomics and Therapy Section, Medical Genomics and Metabolic Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Mother Infant Research Institute, Tufts Medical Center and Tufts Children's Hospital, Boston, MA 02111, USA.
| | - Ashley E Siegel
- Prenatal Genomics and Therapy Section, Medical Genomics and Metabolic Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Mother Infant Research Institute, Tufts Medical Center and Tufts Children's Hospital, Boston, MA 02111, USA
| | - Jeroen L A Pennings
- Center for Health Protection, National Institute for Public Health and the Environment, Bilthoven, BA 3720, the Netherlands
| | - Fatimah Alsebaa
- Mother Infant Research Institute, Tufts Medical Center and Tufts Children's Hospital, Boston, MA 02111, USA
| | - Lauren J Massingham
- Mother Infant Research Institute, Tufts Medical Center and Tufts Children's Hospital, Boston, MA 02111, USA
| | - Umadevi Tantravahi
- Department of Pathology, Women and Infants' Hospital, Providence, RI 02912, USA
| | - Diana W Bianchi
- Prenatal Genomics and Therapy Section, Medical Genomics and Metabolic Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Mother Infant Research Institute, Tufts Medical Center and Tufts Children's Hospital, Boston, MA 02111, USA.
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Kurokawa K, Tsuji M, Takahashi K, Miyagawa K, Mochida-Saito A, Takeda H. Leukemia Inhibitory Factor Participates in the Formation of Stress Adaptation via Hippocampal Myelination in Mice. Neuroscience 2020; 446:1-13. [DOI: 10.1016/j.neuroscience.2020.08.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 08/19/2020] [Accepted: 08/20/2020] [Indexed: 12/27/2022]
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Shaw PR, Klein JA, Aziz NM, Haydar TF. Longitudinal neuroanatomical and behavioral analyses show phenotypic drift and variability in the Ts65Dn mouse model of Down syndrome. Dis Model Mech 2020; 13:dmm046243. [PMID: 32817053 PMCID: PMC7522024 DOI: 10.1242/dmm.046243] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 08/04/2020] [Indexed: 12/16/2022] Open
Abstract
Mouse models of Down syndrome (DS) have been invaluable tools for advancing knowledge of the underlying mechanisms of intellectual disability in people with DS. The Ts(1716)65Dn (Ts65Dn) mouse is one of the most commonly used models as it recapitulates many of the phenotypes seen in individuals with DS, including neuroanatomical changes and impaired learning and memory. In this study, we use rigorous metrics to evaluate multiple cohorts of Ts65Dn ranging from 2014 to the present, including a stock of animals recovered from embryos frozen within ten generations after the colony was first created in 2010. Through quantification of prenatal and postnatal brain development and several behavioral tasks, our results provide a comprehensive comparison of Ts65Dn across time and show a significant amount of variability both across cohorts as well as within cohorts. The inconsistent phenotypes in Ts65Dn mice highlight specific cautions and caveats for use of this model. We outline important steps for ensuring responsible use of Ts65Dn in future research.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Patricia R Shaw
- Graduate Program in Neuroscience, Boston University School of Medicine, Boston, MA 02118, USA
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Jenny A Klein
- Graduate Program in Neuroscience, Boston University School of Medicine, Boston, MA 02118, USA
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Nadine M Aziz
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Tarik F Haydar
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
- Center for Neuroscience Research, Children's National Hospital, Washington, DC 20010, USA
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Aberrant Oligodendrogenesis in Down Syndrome: Shift in Gliogenesis? Cells 2019; 8:cells8121591. [PMID: 31817891 PMCID: PMC6953000 DOI: 10.3390/cells8121591] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/28/2019] [Accepted: 12/04/2019] [Indexed: 12/25/2022] Open
Abstract
Down syndrome (DS), or trisomy 21, is the most prevalent chromosomal anomaly accounting for cognitive impairment and intellectual disability (ID). Neuropathological changes of DS brains are characterized by a reduction in the number of neurons and oligodendrocytes, accompanied by hypomyelination and astrogliosis. Recent studies mainly focused on neuronal development in DS, but underestimated the role of glial cells as pathogenic players. Aberrant or impaired differentiation within the oligodendroglial lineage and altered white matter functionality are thought to contribute to central nervous system (CNS) malformations. Given that white matter, comprised of oligodendrocytes and their myelin sheaths, is vital for higher brain function, gathering knowledge about pathways and modulators challenging oligodendrogenesis and cell lineages within DS is essential. This review article discusses to what degree DS-related effects on oligodendroglial cells have been described and presents collected evidence regarding induced cell-fate switches, thereby resulting in an enhanced generation of astrocytes. Moreover, alterations in white matter formation observed in mouse and human post-mortem brains are described. Finally, the rationale for a better understanding of pathways and modulators responsible for the glial cell imbalance as a possible source for future therapeutic interventions is given based on current experience on pro-oligodendroglial treatment approaches developed for demyelinating diseases, such as multiple sclerosis.
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Rice J, Coutellier L, Weiner JL, Gu C. Region-specific interneuron demyelination and heightened anxiety-like behavior induced by adolescent binge alcohol treatment. Acta Neuropathol Commun 2019; 7:173. [PMID: 31703603 DOI: 10.1186/s40478-019-0829-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/13/2019] [Indexed: 12/12/2022] Open
Abstract
Adolescent binge drinking represents a major public health challenge and can lead to persistent neurological and mental conditions, but the underlying pathogenic mechanisms remain poorly understood. Using a mouse model of adolescent binge ethanol treatment (ABET), we found that this treatment induced behavioral changes associated with demyelination in different brain regions. After ABET, adolescent mice exhibited anxiogenic behaviors with no change in locomotion on the elevated plus maze, and impaired spatial memory indicated by a significant reduction in spontaneous alternation in the Y maze test. Both effects persisted into adulthood. Anatomical studies further showed that ABET induced a significant reduction of parvalbumin-positive (PV+) GABAergic interneurons and myelin density in the hippocampus and medial prefrontal cortex (mPFC). While these deficits in PV+ interneurons and myelin persisted into early adulthood in the hippocampus, the myelin density recovered in the mPFC. Moreover, whereas ABET mainly damaged myelin of PV+ axons in the hippocampus, it primarily damaged myelin of PV-negative axons in the mPFC. Thus, our findings reveal that an adolescent binge alcohol treatment regimen disrupts spatial working memory, increases anxiety-like behaviors, and exerts unique temporal and spatial patterns of gray matter demyelination in the hippocampus and mPFC.
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Lee SE, Duran-Martinez M, Khantsis S, Bianchi DW, Guedj F. Challenges and Opportunities for Translation of Therapies to Improve Cognition in Down Syndrome. Trends Mol Med 2019; 26:150-169. [PMID: 31706840 DOI: 10.1016/j.molmed.2019.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/02/2019] [Accepted: 10/03/2019] [Indexed: 02/07/2023]
Abstract
While preclinical studies have reported improvement of behavioral deficits in the Ts65Dn mouse model of Down syndrome (DS), translation to human clinical trials to improve cognition in individuals with DS has had a poor success record. Timing of the intervention, choice of animal models, strategy for drug selection, and lack of translational endpoints between animals and humans contributed to prior failures of human clinical trials. Here, we focus on in vitro cell models from humans with DS to identify the molecular mechanisms underlying the brain phenotype associated with DS. We emphasize the importance of using these cell models to screen for therapeutic molecules, followed by validating them in the most suitable animal models prior to initiating human clinical trials.
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Affiliation(s)
- Sarah E Lee
- Medical Genetics Branch (Prenatal Genomic and Therapy Section), National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Monica Duran-Martinez
- Medical Genetics Branch (Prenatal Genomic and Therapy Section), National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sabina Khantsis
- Medical Genetics Branch (Prenatal Genomic and Therapy Section), National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Diana W Bianchi
- Medical Genetics Branch (Prenatal Genomic and Therapy Section), National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda 20892, MD, USA
| | - Faycal Guedj
- Medical Genetics Branch (Prenatal Genomic and Therapy Section), National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Nam SM, Kwon HJ, Kim W, Kim JW, Hahn KR, Jung HY, Kim DW, Yoo DY, Seong JK, Hwang IK, Yoon YS. Changes of myelin basic protein in the hippocampus of an animal model of type 2 diabetes. Lab Anim Res 2018; 34:176-184. [PMID: 30671103 PMCID: PMC6333608 DOI: 10.5625/lar.2018.34.4.176] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 10/01/2018] [Accepted: 10/05/2018] [Indexed: 12/31/2022] Open
Abstract
In this study, we observed chronological changes in the immunoreactivity and expression level of myelin basic protein (MBP), one of the most abundant proteins in the central nervous system, in the hippocampus of Zucker diabetic fatty (ZDF) rats and their control littermates (Zucker lean control; ZLC). In the ZLC group, body weight steadily increased with age; the body weight of the ZDF group, however, peaked at 30 weeks of age, and subsequently decreased. Based on the changes of body weight, animals were divided into the following six groups: early (12-week), middle (30-week), and chronic (52-week) diabetic groups and their controls. MBP immunoreactivity was found in the alveus, strata pyramidale, and lacunosum-moleculare of the CA1 region, strata pyramidale and radiatum of the CA3 region, and subgranular zone, polymorphic layer, and molecular layer of the dentate gyrus. MBP immunoreactivity was lowest in the hippocampus of 12-week-old rats in the ZLC group, and highest in 12-week-old rats in the ZDF group. Diabetes increased MBP levels in the 12-week-old group, while MBP immunoreactivity decreased in the 30-week-old group. In the 52-week-old ZLC and ZDF groups, MBP immunoreactivity was detected in the hippocampus, similar to the 30-week-old ZDF group. Western blot results corroborated with immunohistochemical results. These results suggested that changes in the immunoreactivity and expression of MBP in the hippocampus might be a compensatory response to aging, while the sustained levels of MBP in diabetic animals could be attributed to a loss of compensatory responses in oligodendrocytes.
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Affiliation(s)
- Sung Min Nam
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Hyun Jung Kwon
- Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung-Wonju National University, Gangneung, Korea
| | - Woosuk Kim
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Jong Whi Kim
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Kyu Ri Hahn
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Hyo Young Jung
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Dae Won Kim
- Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung-Wonju National University, Gangneung, Korea
| | - Dae Young Yoo
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
- Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan, Korea
| | - Je Kyung Seong
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
- KMPC (Korea Mouse Phenotyping Center), Seoul National University, Seoul, Korea
| | - In Koo Hwang
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Yeo Sung Yoon
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
- KMPC (Korea Mouse Phenotyping Center), Seoul National University, Seoul, Korea
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30
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Stagni F, Giacomini A, Emili M, Uguagliati B, Bonasoni MP, Bartesaghi R, Guidi S. Subicular hypotrophy in fetuses with Down syndrome and in the Ts65Dn model of Down syndrome. Brain Pathol 2018; 29:366-379. [PMID: 30325080 DOI: 10.1111/bpa.12663] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 09/07/2018] [Accepted: 10/02/2018] [Indexed: 12/30/2022] Open
Abstract
Intellectual disability in Down syndrome (DS) has been attributed to neurogenesis impairment during fetal brain development. Consistently with explicit memory alterations observed in children with DS, fetuses with DS exhibit neurogenesis impairment in the hippocampus, a key region involved in memory formation and consolidation. Recent evidence suggests that the subiculum plays a unique role in memory retrieval, a process that is also altered in DS. While much attention has been devoted to the hippocampus, there is a striking lack of information regarding the subiculum of individuals with DS and DS models. In order to fill this gap, in the current study, we examined the subiculum of fetuses with DS and of the Ts65Dn mouse model of DS. We found that in fetuses with DS (gestational week: 17-21), the subiculum had a reduced thickness, a reduced cell density, a reduced density of progenitor cells in the ventricular zone, a reduced percentage of neurons, and an increased percentage of astrocytes and of cells immunopositive for calretinin-a protein expressed by inhibitory interneurons. Similarly to fetuses with DS, the subiculum of neonate Ts65Dn mice was reduced in size, had a reduced number of neurons and a reduced number of proliferating cells. Results suggest that the developmental defects in the subiculum of fetuses with DS may underlie impairment in recall memory and possibly other functions played by the subiculum. The finding that the subiculum of the Ts65Dn mouse exhibits neuroanatomical defects resembling those seen in fetuses with DS further validates the use of this model for preclinical studies.
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Affiliation(s)
- Fiorenza Stagni
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Andrea Giacomini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Marco Emili
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Beatrice Uguagliati
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | | | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Sandra Guidi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
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Sakhon S, Edwards K, Luongo A, Murphy M, Edgin J. Small Sets of Novel Words Are Fully Retained After 1-Week in Typically Developing Children and Down Syndrome: A Fast Mapping Study. J Int Neuropsychol Soc 2018; 24:955-965. [PMID: 30375315 PMCID: PMC6211816 DOI: 10.1017/s1355617718000450] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVES Down syndrome (DS) is a population with known hippocampal impairment, with studies showing that individuals with DS display difficulties in spatial navigation and remembering arbitrary bindings. Recent research has also demonstrated the importance of the hippocampus for novel word-learning. Based on these data, we aimed to determine whether individuals with DS show deficits in learning new labels and if they may benefit from encoding conditions thought to be less reliant on hippocampal function (i.e., through fast mapping). METHODS In the current study, we examined immediate, 5-min, and 1-week delayed word-learning across two learning conditions (e.g., explicit encoding vs. fast mapping). These conditions were examined across groups (twenty-six 3- to 5-year-old typically developing children and twenty-six 11- to 28-year-old individuals with DS with comparable verbal and nonverbal scores on the Kaufman Brief Intelligence Test - second edition) and in reference to sleep quality. RESULTS Both individuals with and without DS showed retention after a 1-week delay, and the current study found no benefit of the fast mapping condition in either group contrary to our expectations. Eye tracking data showed that preferential eye movements to target words were not present immediately but emerged after 1-week in both groups. Furthermore, sleep measures collected via actigraphy did not relate to retention in either group. CONCLUSIONS This study presents novel data on long-term knowledge retention in reference to sleep patterns in DS and adds to a body of knowledge helping us to understand the processes of word-learning in typical and atypically developing populations. (JINS, 2018, 24, 955-965).
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Affiliation(s)
- Stella Sakhon
- Department of Psychology, University of Arizona, Tucson,
Arizona
| | - Kelly Edwards
- Department of Psychology, University of Arizona, Tucson,
Arizona
| | - Alison Luongo
- Department of Psychology, University of Arizona, Tucson,
Arizona
| | - Melanie Murphy
- Department of Psychology, University of Arizona, Tucson,
Arizona
| | - Jamie Edgin
- Department of Psychology, University of Arizona, Tucson,
Arizona
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Bletsch A, Mann C, Andrews DS, Daly E, Tan GMY, Murphy DGM, Ecker C. Down syndrome is accompanied by significantly reduced cortical grey-white matter tissue contrast. Hum Brain Mapp 2018; 39:4043-4054. [PMID: 29885016 DOI: 10.1002/hbm.24230] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 05/02/2018] [Accepted: 05/14/2018] [Indexed: 11/11/2022] Open
Abstract
Increased cortical thickness (CT) has been reported in Down syndrome (DS) during childhood and adolescence, but it remains unclear, which components of the neural architecture underpin these increases and if CT remains altered in adults. Among other factors, differences in CT measures could be driven by reduced tissue contrast between grey and white matter (GWC), which has been reported in neurodegenerative disorders, such as Alzheimer's disease. Using structural magnetic resonance imaging, we therefore examined differences in CT and GWC in 26 adults with DS, and 23 controls, to (1) examine between-group differences in CT in adulthood, (2) establish whether DS is associated with significant reductions in GWC, and (3) determine the influence of GWC variability on between-group differences in CT. As hypothesized, we observed that DS was accompanied by wide-spread increases in CT, and significantly reduced GWC in several large clusters distributed across the cortex. Out of all vertices with a significant between-group difference in CT, 38.50% also displayed a significant reduction in GWC. This percentage of overlap was also statistically significant and extremely unlikely to be obtained by chance (p = .0002). Differences in GWC thus seem to explain some, although not all, of the differences in CT observed in DS. In addition, our study is the first to extend previous in vivo reports of altered CT in DS during childhood and adolescence to older adults, implying that the regional pattern of neuroanatomical differences associated with DS remains stable across the lifespan.
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Affiliation(s)
- Anke Bletsch
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt am Main, Goethe-University Frankfurt am Main, Frankfurt am Main, Germany
| | - Caroline Mann
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt am Main, Goethe-University Frankfurt am Main, Frankfurt am Main, Germany
| | - Derek S Andrews
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London, United Kingdom
| | - Eileen Daly
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London, United Kingdom
| | - Giles M Y Tan
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London, United Kingdom
| | - Declan G M Murphy
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London, United Kingdom
| | - Christine Ecker
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt am Main, Goethe-University Frankfurt am Main, Frankfurt am Main, Germany.,Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London, United Kingdom
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Regulation of Central Nervous System Myelination in Higher Brain Functions. Neural Plast 2018; 2018:6436453. [PMID: 29692804 PMCID: PMC5859868 DOI: 10.1155/2018/6436453] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 01/03/2018] [Indexed: 12/04/2022] Open
Abstract
The hippocampus and the prefrontal cortex are interconnected brain regions, playing central roles in higher brain functions, including learning and memory, planning complex cognitive behavior, and moderating social behavior. The axons in these regions continue to be myelinated into adulthood in humans, which coincides with maturation of personality and decision-making. Myelin consists of dense layers of lipid membranes wrapping around the axons to provide electrical insulation and trophic support and can profoundly affect neural circuit computation. Recent studies have revealed that long-lasting changes of myelination can be induced in these brain regions by experience, such as social isolation, stress, and alcohol abuse, as well as by neurological and psychiatric abnormalities. However, the mechanism and function of these changes remain poorly understood. Myelin regulation represents a new form of neural plasticity. Some progress has been made to provide new mechanistic insights into activity-independent and activity-dependent regulations of myelination in different experimental systems. More extensive investigations are needed in this important but underexplored research field, in order to shed light on how higher brain functions and myelination interplay in the hippocampus and prefrontal cortex.
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Tolentino-Castro JW, Mühlbeier A, Mochizuki L, Wagner H. Delayed Latency of Postural Muscles of Individuals with Intellectual Disabilities. Front Psychol 2018; 9:109. [PMID: 29467709 PMCID: PMC5807919 DOI: 10.3389/fpsyg.2018.00109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/23/2018] [Indexed: 11/13/2022] Open
Abstract
Individuals with intellectual disabilities (ID) (50 < IQ < 79) show impaired motor and postural control, these impairments are highly related to falls and injuries. Recent studies demonstrated these impairments are related with fine and gross motor development, which are more strongly associated with cognition, and consequently language for individuals with ID than for without ID. Despite these studies, little is known about the structure and functioning of this population's spinal cord, which is highly involved in postural control. The aim of our study was to assess the latency of the reflex responses in postural muscles after unexpected lateral external perturbations, in individuals with intellectual disabilities compared to typically developed participants. We assessed 16 participants with intellectual disabilities, 9 males and 7 females (aged 24.06 ± 8.66 years) and 20 typical developed participants (CG), 11 females, 9 males, (aged 21.20±1.96 years). While the participants were in an upright standing position electromyography was used to collect data from M. obliquus externus abdominis (OE) muscles, which were activated by unpredictable perturbations applied by a servomotor on a hand-held grip, following the lateral external perturbation to the trunk. The intellectual disabilities group presented contralateral OE muscles latency of 85.71±27.24 ms, and CG group presented 68.62±10.25 ms, no differences was found. Ipsilateral OE muscles latency also did not differs between the groups, ID group showed 96.60±30.20 ms and CG group showed 95.57±33.53 ms. Our study furthers the knowledge about the muscular activity of individuals with intellectual disabilities. The present experimental results may suggest unique spinal cord processing of individuals with intellectual disabilities when they are faced with unexpected lateral external perturbations.
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Affiliation(s)
- J Walter Tolentino-Castro
- Department of Movement Science, University of Münster, Münster, Germany.,Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
| | - Andreas Mühlbeier
- Department of Movement Science, University of Münster, Münster, Germany
| | - Luis Mochizuki
- Department of Movement Science, College of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil
| | - Heiko Wagner
- Department of Movement Science, University of Münster, Münster, Germany.,Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
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35
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Unfolding the hippocampus: An intrinsic coordinate system for subfield segmentations and quantitative mapping. Neuroimage 2018; 167:408-418. [DOI: 10.1016/j.neuroimage.2017.11.054] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 11/09/2017] [Accepted: 11/22/2017] [Indexed: 11/24/2022] Open
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36
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Stagni F, Giacomini A, Emili M, Guidi S, Bartesaghi R. Neurogenesis impairment: An early developmental defect in Down syndrome. Free Radic Biol Med 2018; 114:15-32. [PMID: 28756311 DOI: 10.1016/j.freeradbiomed.2017.07.026] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 07/24/2017] [Accepted: 07/25/2017] [Indexed: 02/06/2023]
Abstract
Down syndrome (DS) is characterized by brain hypotrophy and intellectual disability starting from early life stages. Accumulating evidence shows that the phenotypic features of the DS brain can be traced back to the fetal period since the DS brain exhibits proliferation potency reduction starting from the critical time window of fetal neurogenesis. This defect is worsened by the fact that neural progenitor cells exhibit reduced acquisition of a neuronal phenotype and an increase in the acquisition of an astrocytic phenotype. Consequently, the DS brain has fewer neurons in comparison with the typical brain. Although apoptotic cell death may be increased in DS, this does not seem to be the major cause of brain hypocellularity. Evidence obtained in brains of individuals with DS, DS-derived induced pluripotent stem cells (iPSCs), and DS mouse models has provided some insight into the mechanisms underlying the developmental defects due to the trisomic condition. Although many triplicated genes may be involved, in the light of the studies reviewed here, DYRK1A, APP, RCAN1 and OLIG1/2 appear to be particularly important determinants of many neurodevelopmental alterations that characterize DS because their triplication affects both the proliferation and fate of neural precursor cells as well as apoptotic cell death. Based on the evidence reviewed here, pathways downstream to these genes may represent strategic targets, for the design of possible interventions.
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Affiliation(s)
- Fiorenza Stagni
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Andrea Giacomini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Marco Emili
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Sandra Guidi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
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37
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GABA A receptor subunit deregulation in the hippocampus of human foetuses with Down syndrome. Brain Struct Funct 2017; 223:1501-1518. [PMID: 29168008 PMCID: PMC5869939 DOI: 10.1007/s00429-017-1563-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 11/05/2017] [Indexed: 11/01/2022]
Abstract
The function, regulation and cellular distribution of GABAA receptor subunits have been extensively documented in the adult rodent brain and are linked to numerous neurological disorders. However, there is a surprising lack of knowledge on the cellular (sub-) distribution of GABAA receptor subunits and of their expressional regulation in developing healthy and diseased foetal human brains. To propose a role for GABAA receptor subunits in neurodevelopmental disorders, we studied the developing hippocampus of normal and Down syndrome foetuses. Among the α1-3 and γ2 subunits probed, we find significantly altered expression profiles of the α1, α3 and γ2 subunits in developing Down syndrome hippocampi, with the α3 subunit being most affected. α3 subunits were selectively down-regulated in all hippocampal subfields and developmental periods tested in Down syndrome foetuses, presenting a developmental mismatch by their adult-like distribution in early foetal development. We hypothesized that increased levels of the amyloid precursor protein (APP), and particularly its neurotoxic β-amyloid (1-42) fragment, could disrupt α3 gene expression, likely by facilitating premature neuronal differentiation. Indeed, we find increased APP content in the hippocampi of the Down foetuses. In a corresponding cellular model, soluble β-amyloid (1-42) administered to cultured SH-SY5Y neuroblastoma cells, augmented by retinoic acid-induced differentiation towards a neuronal phenotype, displayed a reduction in α3 subunit levels. In sum, this study charts a comprehensive regional and subcellular map of key GABAA receptor subunits in identified neuronal populations in the hippocampus of healthy and Down syndrome foetuses and associates increased β-amyloid load with discordant down-regulation of α3 subunits.
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Clark CA, Fernandez F, Sakhon S, Spanò G, Edgin JO. The medial temporal memory system in Down syndrome: Translating animal models of hippocampal compromise. Hippocampus 2017; 27:683-691. [PMID: 28346765 PMCID: PMC8109260 DOI: 10.1002/hipo.22724] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 09/06/2016] [Accepted: 03/07/2017] [Indexed: 01/19/2023]
Abstract
Recent studies have highlighted the dentate gyrus as a region of increased vulnerability in mouse models of Down syndrome (DS). It is unclear to what extent these findings are reflected in the memory profile of people with the condition. We developed a series of novel tasks to probe distinct medial temporal functions in children and young adults with DS, including object, spatial, and temporal order memory. Relative to mental age-matched controls (n = 45), individuals with DS (n = 28) were unimpaired on subtests involving short-term object or configural recall that was divorced from spatial or temporal contexts. By contrast, the DS group had difficulty recalling spatial locations when contextual information was salient and recalling the order in which objects were serially presented. Results are consistent with dysfunction of spatial and temporal contextual pattern separation abilities in individuals with DS, mediated by the hippocampus, including the dentate gyrus. Amidst increasing calls to bridge human and animal work, the memory profile demonstrated here in humans with DS is strikingly similar to that of the Ts65Dn mouse model of DS. The study highlights the trisynaptic circuit as a potentially fruitful intervention target to mitigate cognitive impairments associated with DS.
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Affiliation(s)
- Caron A.C. Clark
- Department of Psychology, Memory Development and Disorders Laboratory, University of Arizona, Tucson, Arizona
- Department of Educational Psychology, University of Nebraska, Lincoln, Nebraska
| | - Fabian Fernandez
- Department of Psychology, BIO5 and McKnight Brain Research Institutes, University of Arizona, Tucson, Arizona
- Department of Neurology, BIO5 and McKnight Brain Research Institutes, University of Arizona, Tucson, Arizona
| | - Stella Sakhon
- Department of Psychology, Memory Development and Disorders Laboratory, University of Arizona, Tucson, Arizona
| | - Goffredina Spanò
- Department of Psychology, Memory Development and Disorders Laboratory, University of Arizona, Tucson, Arizona
| | - Jamie O. Edgin
- Department of Psychology, Memory Development and Disorders Laboratory, University of Arizona, Tucson, Arizona
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Milenkovic I, Jarc J, Dassler E, Aronica E, Iyer A, Adle-Biassette H, Scharrer A, Reischer T, Hainfellner JA, Kovacs GG. The physiological phosphorylation of tau is critically changed in fetal brains of individuals with Down syndrome. Neuropathol Appl Neurobiol 2017; 44:314-327. [PMID: 28455903 DOI: 10.1111/nan.12406] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 03/17/2017] [Accepted: 04/15/2017] [Indexed: 01/15/2023]
Abstract
AIMS Down syndrome (DS) is a common cause of mental retardation accompanied by cognitive impairment. Comprehensive studies suggested a link between development and ageing, as nearly all individuals with DS develop Alzheimer disease (AD)-like pathology. However, there is still a paucity of data on tau in early DS to support this notion. METHODS Using morphometric immunohistochemistry we compared tau phosphorylation in normal brains and in brains of individuals with DS from early development until early postnatal life. RESULTS We observed in DS a critical loss of physiological phosphorylation of tau. Rhombencephalic structures showed prominent differences between controls and DS using antibodies AT8 (Ser-202/Thr-205) and AT180 (Thr-231). In contrast, in the subiculum only a small portion of controls deviated from DS using antibodies AT100 (Thr-212/Ser-214) and AT270 (Thr-181). With exception of the subiculum, phosphorylation-independent tau did not differ between groups, as confirmed by immunostaining for the HT-7 antibody (epitope between 159 and 163 of the human tau) as well. DISCUSSION Our observations suggest functional tau disturbance in DS brains during development, rather than axonal loss. This supports the role of tau as a further important player in the pathophysiology of cognitive impairment in DS and related AD.
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Affiliation(s)
- I Milenkovic
- Department of Neurology, Medical University of Vienna, Vienna, Austria.,Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - J Jarc
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - E Dassler
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - E Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, The Netherlands.,SEIN - Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, The Netherlands
| | - A Iyer
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - H Adle-Biassette
- Inserm U1141, Paris, France.,Univ Paris Diderot, Sorbonne Paris Cité, UMRS 676, Paris, France.,Lariboisière Hospital, APHP, Paris, France
| | - A Scharrer
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - T Reischer
- Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria
| | - J A Hainfellner
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - G G Kovacs
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
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40
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Spanò G, Intraub H, Edgin JO. Testing the "Boundaries" of boundary extension: Anticipatory scene representation across development and disorder. Hippocampus 2017; 27:726-739. [PMID: 28329909 DOI: 10.1002/hipo.22728] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Revised: 01/14/2017] [Accepted: 01/19/2017] [Indexed: 12/28/2022]
Abstract
Recent studies have suggested that Boundary Extension (BE), a scene construction error, may be linked to the function of the hippocampus. In this study, we tested BE in two groups with variations in hippocampal development and disorder: a typically developing sample ranging from preschool to adolescence and individuals with Down syndrome. We assessed BE across three different test modalities: drawing, visual recognition, and a 3D scene boundary reconstruction task. Despite confirmed fluctuations in memory function measured through a neuropsychological assessment, the results showed consistent BE in all groups across test modalities, confirming the near universal nature of BE. These results indicate that BE is an essential function driven by a complex set of processes, that occur even in the face of delayed memory development and hippocampal dysfunction in special populations.
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Affiliation(s)
- G Spanò
- Department of Psychology, University of Arizona, Tucson, Arizona, 85721.,Cognitive Science Program, University of Arizona, Tucson, Arizona, 85721
| | - H Intraub
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, 19716
| | - J O Edgin
- Department of Psychology, University of Arizona, Tucson, Arizona, 85721.,Cognitive Science Program, University of Arizona, Tucson, Arizona, 85721.,Sonoran University Center for Excellence in Developmental Disabilities, University of Arizona, Tucson, Arizona, 85721
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Abstract
PURPOSE This study compared differences in motor development in infants with Down syndrome beginning a tummy time intervention before 11 weeks of age and after 11 weeks of age. METHODS Nineteen infants with Down syndrome participated in tummy time until they could independently transition in and out of sitting. Motor development was assessed monthly using the Bayley III Motor Scales and compared between the groups. RESULTS A difference in motor development between early and late groups is apparent 1, 2, and 3 months following intervention initiation. CONCLUSION Early implemented tummy time was effective in reducing motor delay in young infants with Down syndrome and is a prudent first step in intervention.
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42
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Maglorius Renkilaraj MRL, Baudouin L, Wells CM, Doulazmi M, Wehrlé R, Cannaya V, Bachelin C, Barnier JV, Jia Z, Nait Oumesmar B, Dusart I, Bouslama-Oueghlani L. The intellectual disability protein PAK3 regulates oligodendrocyte precursor cell differentiation. Neurobiol Dis 2016; 98:137-148. [PMID: 27940202 DOI: 10.1016/j.nbd.2016.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 11/04/2016] [Accepted: 12/02/2016] [Indexed: 10/20/2022] Open
Abstract
Oligodendrocyte and myelin deficits have been reported in mental/psychiatric diseases. The p21-activated kinase 3 (PAK3), a serine/threonine kinase, whose activity is stimulated by the binding of active Rac and Cdc42 GTPases is affected in these pathologies. Indeed, many mutations of Pak3 gene have been described in non-syndromic intellectual disability diseases. Pak3 is expressed mainly in the brain where its role has been investigated in neurons but not in glial cells. Here, we showed that PAK3 is highly expressed in oligodendrocyte precursors (OPCs) and its expression decreases in mature oligodendrocytes. In the developing white matter of the Pak3 knockout mice, we found defects of oligodendrocyte differentiation in the corpus callosum and to a lesser extent in the anterior commissure, which were compensated at the adult stage. In vitro experiments in OPC cultures, derived from Pak3 knockout and wild type brains, support a developmental and cell-autonomous role for PAK3 in regulating OPC differentiation into mature oligodendrocytes. Moreover, we did not detect any obvious alterations of the proliferation or migration of Pak3 null OPCs compared to wild type. Overall, our data highlight PAK3 as a new regulator of OPC differentiation.
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Affiliation(s)
| | - Lucas Baudouin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | | | - Mohamed Doulazmi
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Adaptation Biologique et vieillissement, F-75005 Paris, France
| | - Rosine Wehrlé
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Vidjeacoumary Cannaya
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Corinne Bachelin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | - Jean-Vianney Barnier
- Institute of Neuroscience Paris-Saclay, CNRS-Université Paris-Sud, UMR9197, F-91405 Orsay, France
| | - Zhengping Jia
- Neurosciences & Mental Health, The Hospital for Sick Children, and Department of Physiology, Faculty of Medicine, University of Toronto, 555 University, Toronto, Ontario M5G 1X8, Canada
| | - Brahim Nait Oumesmar
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | - Isabelle Dusart
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Lamia Bouslama-Oueghlani
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France.
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43
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Startin CM, Hamburg S, Hithersay R, Davies A, Rodger E, Aggarwal N, Al-Janabi T, Strydom A. The LonDownS adult cognitive assessment to study cognitive abilities and decline in Down syndrome. Wellcome Open Res 2016; 1:11. [PMID: 28018980 PMCID: PMC5176078 DOI: 10.12688/wellcomeopenres.9961.1] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Background: Down syndrome (DS), the most common genetic cause of intellectual disability, is associated with an ultra-high risk of developing Alzheimer’s disease. However, there is individual variability in the onset of clinical dementia and in baseline cognitive abilities prior to decline, particularly in memory, executive functioning, and motor coordination. The LonDownS Consortium aims to determine risk and protective factors for the development of dementia and factors relating to cognitive abilities in people with DS. Here we describe our cognitive test battery and related informant measures along with reporting data from our baseline cognitive and informant assessments. Methods: We developed a cognitive test battery to assess general abilities, memory, executive function, and motor coordination abilities in adults with DS, with informant ratings of similar domains also collected, designed to allow for data on a broad range of participants. Participants (n=305) had a range of ages and abilities, and included adults with and without a clinical diagnosis of dementia. Results: Results suggest the battery is suitable for the majority of adults with DS, although approximately half the adults with dementia were unable to undertake any cognitive task. Many test outcomes showed a range of scores with low floor and ceiling effects. Non-verbal age-adjusted IQ scores had lower floor effects than verbal IQ scores. Before the onset of any cognitive decline, females aged 16-35 showed better verbal abilities compared to males. We also identified clusters of cognitive test scores within our battery related to visuospatial memory, motor coordination, language abilities, and processing speed / sustained attention. Conclusions: Our further studies will use baseline and longitudinal assessments to explore factors influencing cognitive abilities and cognitive decline related to ageing and onset of dementia in adults with DS.
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Affiliation(s)
- Carla M Startin
- UCL Division of Psychiatry, University College London, London, UK.,The LonDownS Consortium, University College London, London, UK
| | - Sarah Hamburg
- UCL Division of Psychiatry, University College London, London, UK.,The LonDownS Consortium, University College London, London, UK
| | - Rosalyn Hithersay
- UCL Division of Psychiatry, University College London, London, UK.,The LonDownS Consortium, University College London, London, UK
| | - Amy Davies
- UCL Division of Psychiatry, University College London, London, UK.,Faculty of Health and Medical Sciences, University of Surrey, Guilford, UK
| | - Erin Rodger
- UCL Division of Psychiatry, University College London, London, UK
| | - Nidhi Aggarwal
- UCL Division of Psychiatry, University College London, London, UK
| | - Tamara Al-Janabi
- UCL Division of Psychiatry, University College London, London, UK.,The LonDownS Consortium, University College London, London, UK
| | - André Strydom
- UCL Division of Psychiatry, University College London, London, UK.,The LonDownS Consortium, University College London, London, UK
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44
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Meraviglia V, Ulivi AF, Boccazzi M, Valenza F, Fratangeli A, Passafaro M, Lecca D, Stagni F, Giacomini A, Bartesaghi R, Abbracchio MP, Ceruti S, Rosa P. SNX27, a protein involved in down syndrome, regulates GPR17 trafficking and oligodendrocyte differentiation. Glia 2016; 64:1437-60. [DOI: 10.1002/glia.23015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 05/11/2016] [Accepted: 05/13/2016] [Indexed: 12/26/2022]
Affiliation(s)
- Veronica Meraviglia
- CNR - Institute of Neuroscience, Department of Medical Biotechnologies and Translational Medicine (BIOMETRA); Università Degli Studi Di Milano; Milan Italy
| | - Alessandro Francesco Ulivi
- CNR - Institute of Neuroscience, Department of Medical Biotechnologies and Translational Medicine (BIOMETRA); Università Degli Studi Di Milano; Milan Italy
| | - Marta Boccazzi
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmacological and Biomolecular Sciences (DiSFeB); Università Degli Studi Di Milano; Milan Italy
| | - Fabiola Valenza
- CNR - Institute of Neuroscience, Department of Medical Biotechnologies and Translational Medicine (BIOMETRA); Università Degli Studi Di Milano; Milan Italy
| | - Alessandra Fratangeli
- CNR - Institute of Neuroscience, Department of Medical Biotechnologies and Translational Medicine (BIOMETRA); Università Degli Studi Di Milano; Milan Italy
| | - Maria Passafaro
- CNR - Institute of Neuroscience, Department of Medical Biotechnologies and Translational Medicine (BIOMETRA); Università Degli Studi Di Milano; Milan Italy
| | - Davide Lecca
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmacological and Biomolecular Sciences (DiSFeB); Università Degli Studi Di Milano; Milan Italy
| | - Fiorenza Stagni
- Department of Biomedical and Neuromotor Sciences; Università Degli Studi Di Bologna; Bologna Italy
| | - Andrea Giacomini
- Department of Biomedical and Neuromotor Sciences; Università Degli Studi Di Bologna; Bologna Italy
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences; Università Degli Studi Di Bologna; Bologna Italy
| | - Maria P. Abbracchio
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmacological and Biomolecular Sciences (DiSFeB); Università Degli Studi Di Milano; Milan Italy
| | - Stefania Ceruti
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmacological and Biomolecular Sciences (DiSFeB); Università Degli Studi Di Milano; Milan Italy
| | - Patrizia Rosa
- CNR - Institute of Neuroscience, Department of Medical Biotechnologies and Translational Medicine (BIOMETRA); Università Degli Studi Di Milano; Milan Italy
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45
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Spanò G, Edgin JO. Everyday memory in individuals with Down syndrome: Validation of the Observer Memory Questionnaire - Parent Form. Child Neuropsychol 2016; 23:523-535. [PMID: 26981787 DOI: 10.1080/09297049.2016.1150446] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The memory profile of individuals with Down syndrome (DS) has mainly been examined through traditional laboratory tasks, often revealing substantial deficits in episodic and declarative memory. Little is known about the relation between memory abilities as measured in the laboratory versus naturalistic settings in this population, and no questionnaire assessments of everyday memory have been formally validated for this group. The current study's aims were twofold: 1) to describe the psychometric characteristics of a parent-reported everyday memory measure (the Observer Memory Questionnaire - Parent Form, OMQ-PF) in this population with known hippocampal and memory impairment (i.e., DS, ages 7-35 years), and 2) to determine if the measure has the sensitivity to detect impairments, thus providing some of the first data to document parent reports of everyday memory in individuals with DS. The results indicate that this scale is a reliable instrument for detecting and tracking memory deficits over time in this population. We found a correlation between parent reports of everyday memory difficulties and well-replicated deficits in a laboratory-based memory task (i.e., place-object paired associates learning). Our results suggest that the OMQ-PF has the potential to be used as a tool to help to track the status of memory function in this group both for use in descriptive studies and in studies of behavior and pharmacological intervention.
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Affiliation(s)
- Goffredina Spanò
- a Department of Psychology , University of Arizona , Tucson , USA
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46
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Olmos-Serrano JL, Kang HJ, Tyler WA, Silbereis JC, Cheng F, Zhu Y, Pletikos M, Jankovic-Rapan L, Cramer NP, Galdzicki Z, Goodliffe J, Peters A, Sethares C, Delalle I, Golden JA, Haydar TF, Sestan N. Down Syndrome Developmental Brain Transcriptome Reveals Defective Oligodendrocyte Differentiation and Myelination. Neuron 2016; 89:1208-1222. [PMID: 26924435 DOI: 10.1016/j.neuron.2016.01.042] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 11/24/2015] [Accepted: 01/21/2016] [Indexed: 11/18/2022]
Abstract
Trisomy 21, or Down syndrome (DS), is the most common genetic cause of developmental delay and intellectual disability. To gain insight into the underlying molecular and cellular pathogenesis, we conducted a multi-region transcriptome analysis of DS and euploid control brains spanning from mid-fetal development to adulthood. We found genome-wide alterations in the expression of a large number of genes, many of which exhibited temporal and spatial specificity and were associated with distinct biological processes. In particular, we uncovered co-dysregulation of genes associated with oligodendrocyte differentiation and myelination that were validated via cross-species comparison to Ts65Dn trisomy mice. Furthermore, we show that hypomyelination present in Ts65Dn mice is in part due to cell-autonomous effects of trisomy on oligodendrocyte differentiation and results in slower neocortical action potential transmission. Together, these results identify defects in white matter development and function in DS, and they provide a transcriptional framework for further investigating DS neuropathogenesis.
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Affiliation(s)
- Jose Luis Olmos-Serrano
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Hyo Jung Kang
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
- Department of Life Science, Chung-Ang University, Seoul, Korea
| | - William A Tyler
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - John C Silbereis
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Feng Cheng
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida, USA
| | - Ying Zhu
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Mihovil Pletikos
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Lucija Jankovic-Rapan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Nathan P Cramer
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Zygmunt Galdzicki
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Joseph Goodliffe
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Alan Peters
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Claire Sethares
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Ivana Delalle
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Jeffrey A Golden
- Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Tarik F Haydar
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Nenad Sestan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
- Departments of Genetic and Psychiatry, Program in Cellular Neuroscience, Neurodegeneration and Repair, Section of Comparative Medicine and Child Study Center, Yale School of Medicine, New Haven, Connecticut, USA
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47
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Wei W, Wang Y, Dong J, Wang Y, Min H, Song B, Shan Z, Teng W, Xi Q, Chen J. Hypothyroxinemia induced by maternal mild iodine deficiency impairs hippocampal myelinated growth in lactational rats. ENVIRONMENTAL TOXICOLOGY 2015; 30:1264-1274. [PMID: 24753110 DOI: 10.1002/tox.21997] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 04/01/2014] [Accepted: 04/04/2014] [Indexed: 06/03/2023]
Abstract
Hypothyroxinemia induced by maternal mild iodine deficiency causes neurological deficits and impairments of brain function in offspring. Hypothyroxinemia is prevalent in developing and developed countries alike. However, the mechanism underlying these deficits remains less well known. Given that the myelin plays an important role in learning and memory function, we hypothesize that hippocampal myelinated growth may be impaired in rat offspring exposed to hypothyroxinemia induced by maternal mild iodine deficiency. To test this hypothesis, the female Wistar rats were used and four experimental groups were prepared: (1) control; (2) maternal mild iodine deficiency diet inducing hypothyroxinemia; (3) hypothyroidism induced by maternal severe iodine deficiency diet; (4) hypothyroidism induced by maternal methimazole water. The rats were fed the diet from 3 months before pregnancy to the end of lactation. Our results showed that the physiological changes occuring in the hippocampal myelin were altered in the mild iodine deficiency group as indicated by the results of immunofluorescence of myelin basic proteins on postnatal day 14 and postnatal day 21. Moreover, hypothyroxinemia reduced the expressions of oligodendrocyte lineage transcription factor 2 and myelin-related proteins in the treatments on postnatal day 14 and postnatal day 21. Our data suggested that hypothyroxinemia induced by maternal mild iodine deficiency may impair myelinated growth of the offspring.
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Affiliation(s)
- Wei Wei
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Yi Wang
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Jing Dong
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Yuan Wang
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
| | - Hui Min
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
| | - Binbin Song
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
| | - Zhongyan Shan
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Weiping Teng
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Qi Xi
- Department of Physiology, the University of Tennessee Health Science Center, Memphis, Tennessee, 38163, USA
| | - Jie Chen
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
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48
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Fernandez F, Reeves RH. Assessing cognitive improvement in people with Down syndrome: important considerations for drug-efficacy trials. Handb Exp Pharmacol 2015; 228:335-80. [PMID: 25977089 DOI: 10.1007/978-3-319-16522-6_12] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Experimental research over just the past decade has raised the possibility that learning deficits connected to Down syndrome (DS) might be effectively managed by medication. In the current chapter, we touch on some of the work that paved the way for these advances and discuss the challenges associated with translating them. In particular, we highlight sources of phenotypic variability in the DS population that are likely to impact performance assessments. Throughout, suggestions are made on how to detect meaningful changes in cognitive-adaptive function in people with DS during drug treatment. The importance of within-subjects evaluation is emphasized.
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Affiliation(s)
- Fabian Fernandez
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA,
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49
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Evidence of altered age-related brain cytoarchitecture in mouse models of down syndrome: a diffusional kurtosis imaging study. Magn Reson Imaging 2014; 33:437-47. [PMID: 25527393 DOI: 10.1016/j.mri.2014.12.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/26/2014] [Accepted: 12/01/2014] [Indexed: 11/22/2022]
Abstract
Mouse models of Down syndrome (DS) exhibit abnormal brain developmental and neurodegenerative changes similar to those seen in individuals with DS. Although DS mice have been well characterized cognitively and morphologically there are no prior reports utilizing diffusion MRI. In this study we investigated the ability of diffusional kurtosis imaging (DKI) to detect the progressive developmental and neurodegenerative changes in the Ts65Dn (TS) DS mouse model. TS mice displayed higher diffusional kurtosis (DK) in the frontal cortex (FC) compared to normal mice at 2months of age. At 5months of age, TS mice had lower radial kurtosis in the striatum (ST), which persisted in the 8-month-old mice. The TS mice exhibited lower DK metrics values in the dorsal hippocampus (HD) at all ages, and the group difference in this region was larger at 8-months. Regression analysis showed that normal mice had a significant age-related increase in DK metrics in FC, ST and HD. On the contrary, the TS mice lacked significant age-related increase in DK metrics in FC and ST. Although preliminary, these results demonstrate that DK metrics can detect TS brain developmental and neurodegenerative abnormalities.
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50
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Roberts LV, Richmond JL. Preschoolers with Down syndrome do not yet show the learning and memory impairments seen in adults with Down syndrome. Dev Sci 2014; 18:404-19. [PMID: 25283764 DOI: 10.1111/desc.12225] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 06/04/2014] [Indexed: 12/01/2022]
Abstract
Individuals with Down syndrome (DS) exhibit a behavioral phenotype of specific strengths and weaknesses, in addition to a generalized cognitive delay. In particular, adults with DS exhibit specific deficits in learning and memory processes that depend on the hippocampus, and there is some suggestion of impairments on executive function tasks that depend on the prefrontal cortex. While these functions have been investigated in adults with DS, it is largely unclear how these processes develop in young children with DS. Here we tested preschoolers with DS and typically developing children, age-matched on either receptive language or non-verbal scores as a proxy for mental age (MA), on a battery of eye-tracking and behavioral measures that have been shown to depend on the hippocampus or the prefrontal cortex. Preschoolers with DS performed equivalently to MA-matched controls, suggesting that the disability-specific memory deficits documented in adults with DS, in addition to a cognitive delay, are not yet evident in preschoolers with DS, and likely emerge progressively with age. Our results reinforce the idea that early childhood may be a critical time frame for targeted early intervention. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=r6GUA6my22Q&list=UU3FIcom6UpITHZOIEa8Onnw.
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Affiliation(s)
- Lynette V Roberts
- School of Psychology, University of New South Wales, Sydney, Australia
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