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Glass TJ, Russell JA, Fisher EH, Ostadi M, Aori N, Yu YE, Connor NP. Altered tongue muscle contractile properties coincide with altered swallow function in the adult Ts65Dn mouse model of down syndrome. Front Neurol 2024; 15:1384572. [PMID: 38585362 PMCID: PMC10995394 DOI: 10.3389/fneur.2024.1384572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 03/08/2024] [Indexed: 04/09/2024] Open
Abstract
Purpose Down syndrome (DS) is a developmental disability associated with difficulties in deglutition. The adult Ts65Dn mouse model of DS has been previously shown to have differences in measures of swallowing compared with euploid controls. However, the putative mechanisms of these differences in swallowing function are unclear. This study tested the hypothesis that the Ts65Dn genotype is associated with atypical measures of tongue muscle contractile properties, coinciding with atypical swallow function. Methods Adult (5-month-old) Ts65Dn (n = 15 female, 14 male) and euploid sibling controls (n = 16 female, 14 male) were evaluated through videofluoroscopy swallow studies (VFSS) to quantify measures of swallowing performance including swallow rate and inter-swallow interval (ISI). After VFSS, retrusive tongue muscle contractile properties, including measures of muscle fatigue, were determined using bilateral hypoglossal nerve stimulation. Results The Ts65Dn group had significantly slower swallow rates, significantly greater ISI times, significantly slower rates of tongue force development, and significantly greater levels of tongue muscle fatigue, with lower retrusive tongue forces than controls in fatigue conditions. Conclusion Tongue muscle contractile properties are altered in adult Ts65Dn and coincide with altered swallow function.
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Affiliation(s)
- Tiffany J. Glass
- Department of Surgery, Division of Otolaryngology, University of Wisconsin-Madison, Madison, WI, United States
| | - John A. Russell
- Department of Surgery, Division of Otolaryngology, University of Wisconsin-Madison, Madison, WI, United States
| | - Erin H. Fisher
- Department of Surgery, Division of Otolaryngology, University of Wisconsin-Madison, Madison, WI, United States
| | - Marziyeh Ostadi
- Department of Surgery, Division of Otolaryngology, University of Wisconsin-Madison, Madison, WI, United States
- Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, WI, United States
| | - Nanyumuzi Aori
- Department of Surgery, Division of Otolaryngology, University of Wisconsin-Madison, Madison, WI, United States
| | - Y. Eugene Yu
- The Children’s Guild Foundation Down Syndrome Research Program, Department of Cancer Genetics and Genomics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States
- Genetics, Genomics and Bioinformatics Program, State University of New York at Buffalo, Buffalo, NY, United States
| | - Nadine P. Connor
- Department of Surgery, Division of Otolaryngology, University of Wisconsin-Madison, Madison, WI, United States
- Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, WI, United States
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Llambrich S, Tielemans B, Saliën E, Atzori M, Wouters K, Van Bulck V, Platt M, Vanherp L, Gallego Fernandez N, Grau de la Fuente L, Poptani H, Verlinden L, Himmelreich U, Croitor A, Attanasio C, Callaerts-Vegh Z, Gsell W, Martínez-Abadías N, Vande Velde G. Pleiotropic effects of trisomy and pharmacologic modulation on structural, functional, molecular, and genetic systems in a Down syndrome mouse model. eLife 2024; 12:RP89763. [PMID: 38497812 PMCID: PMC10948151 DOI: 10.7554/elife.89763] [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] [Indexed: 03/19/2024] Open
Abstract
Down syndrome (DS) is characterized by skeletal and brain structural malformations, cognitive impairment, altered hippocampal metabolite concentration and gene expression imbalance. These alterations were usually investigated separately, and the potential rescuing effects of green tea extracts enriched in epigallocatechin-3-gallate (GTE-EGCG) provided disparate results due to different experimental conditions. We overcame these limitations by conducting the first longitudinal controlled experiment evaluating genotype and GTE-EGCG prenatal chronic treatment effects before and after treatment discontinuation. Our findings revealed that the Ts65Dn mouse model reflected the pleiotropic nature of DS, exhibiting brachycephalic skull, ventriculomegaly, neurodevelopmental delay, hyperactivity, and impaired memory robustness with altered hippocampal metabolite concentration and gene expression. GTE-EGCG treatment modulated most systems simultaneously but did not rescue DS phenotypes. On the contrary, the treatment exacerbated trisomic phenotypes including body weight, tibia microarchitecture, neurodevelopment, adult cognition, and metabolite concentration, not supporting the therapeutic use of GTE-EGCG as a prenatal chronic treatment. Our results highlight the importance of longitudinal experiments assessing the co-modulation of multiple systems throughout development when characterizing preclinical models in complex disorders and evaluating the pleiotropic effects and general safety of pharmacological treatments.
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Affiliation(s)
- Sergi Llambrich
- Biomedical MRI, Department of Imaging and Pathology, KU LeuvenLeuvenBelgium
| | - Birger Tielemans
- Biomedical MRI, Department of Imaging and Pathology, KU LeuvenLeuvenBelgium
| | - Ellen Saliën
- Biomedical MRI, Department of Imaging and Pathology, KU LeuvenLeuvenBelgium
| | - Marta Atzori
- Department of Human Genetics, KU LeuvenLeuvenBelgium
| | - Kaat Wouters
- Laboratory of Biological Psychology, KU LeuvenLeuvenBelgium
| | | | - Mark Platt
- Centre for Preclinical Imaging, Department of Molecular and Clinical Cancer Medicine, University of LiverpoolLiverpoolUnited Kingdom
| | - Laure Vanherp
- Biomedical MRI, Department of Imaging and Pathology, KU LeuvenLeuvenBelgium
| | - Nuria Gallego Fernandez
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals (BEECA), Facultat de Biologia, Universitat de BarcelonaBarcelonaSpain
| | - Laura Grau de la Fuente
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals (BEECA), Facultat de Biologia, Universitat de BarcelonaBarcelonaSpain
| | - Harish Poptani
- Centre for Preclinical Imaging, Department of Molecular and Clinical Cancer Medicine, University of LiverpoolLiverpoolUnited Kingdom
| | - Lieve Verlinden
- Clinical and Experimental Endocrinology, KU LeuvenLeuvenBelgium
| | - Uwe Himmelreich
- Biomedical MRI, Department of Imaging and Pathology, KU LeuvenLeuvenBelgium
| | - Anca Croitor
- Biomedical MRI, Department of Imaging and Pathology, KU LeuvenLeuvenBelgium
| | | | | | - Willy Gsell
- Biomedical MRI, Department of Imaging and Pathology, KU LeuvenLeuvenBelgium
| | - Neus Martínez-Abadías
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals (BEECA), Facultat de Biologia, Universitat de BarcelonaBarcelonaSpain
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Glass TJ, Lenell C, Fisher EH, Yang Q, Connor NP. Ultrasonic vocalization phenotypes in the Ts65Dn and Dp(16)1Yey mouse models of Down syndrome. Physiol Behav 2023; 271:114323. [PMID: 37573959 PMCID: PMC10592033 DOI: 10.1016/j.physbeh.2023.114323] [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: 05/09/2023] [Revised: 07/18/2023] [Accepted: 08/10/2023] [Indexed: 08/15/2023]
Abstract
Down syndrome (DS) is a developmental disorder associated with a high incidence of challenges in vocal communication. DS can involve medical co-morbidities and structural social factors that may impact communication outcomes, which can present difficulties for the study of vocal communication challenges. Mouse models of DS may be used to study vocal communication differences associated with this syndrome and allow for greater control and consistency of environmental factors. Prior work has demonstrated differences in ultrasonic vocalization (USV) of the Ts65Dn mouse model of DS at a young adult age, however it is not known how USV characteristics are manifested at mature ages. Given that the aging process and age-related co-morbidities may also impact communication in DS, addressing this gap in knowledge may be of value for efforts to understand communication difficulties in DS across the lifespan. The current study hypothesized that the Ts65Dn and Dp(16)1Yey mouse models of DS would demonstrate differences in multiple measures of USV communication at a mature adult age of 5 months. METHODS Ts65Dn mice (n = 16) and euploid controls (n = 19), as well as Dp(16)1Yey mice (n = 20) and wild-type controls (n = 22), were evaluated at 5 months of age for USV production using a mating paradigm. Video footage of USV sessions were analyzed to quantify social behaviors of male mice during USV testing sessions. USV recordings were analyzed using Deepsqueak software to identify 10 vocalization types, which were quantified for 11 acoustic measures. RESULTS Ts65Dn, but not Dp(16)1Yey, showed significantly lower proportions of USVs classified as Step Up, Short, and Frequency Steps, and significantly higher proportions of USVs classified as Inverted U, than euploid controls. Both Ts65Dn and Dp(16)1Yey groups had significantly greater values for power and tonality for USVs than respective control groups. While Ts65Dn showed lower frequencies than controls, Dp(16)1Yey showed higher frequencies than controls. Finally, Ts65Dn showed reductions in a measure of complexity for some call types. No significant differences between genotype groups were identified in analysis of behaviors during testing sessions. CONCLUSION While both Ts65Dn and Dp(16)1Yey show significant differences in USV measures at 5 months of age, of the two models, Ts65Dn shows a relatively greater numbers of differences. Characterization of communication phenotypes in mouse models of DS may be helpful in laying the foundation for future translational advances in the area of communication difficulties associated with DS.
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Affiliation(s)
- Tiffany J Glass
- Department of Surgery, Division of Otolaryngology, University of Wisconsin, Madison, WI, USA.
| | - Charles Lenell
- Department of Communication Sciences and Disorders, University of Northern Colorado, Greeley, CO, USA
| | - Erin H Fisher
- Department of Surgery, Division of Otolaryngology, University of Wisconsin, Madison, WI, USA
| | - Qiuyu Yang
- Department of Surgery, Statistical Analysis and Research Programming Core, University of Wisconsin, Madison, WI, USA
| | - Nadine P Connor
- Department of Surgery, Division of Otolaryngology, University of Wisconsin, Madison, WI, USA; Department of Communication Sciences and Disorders, University of Wisconsin, Madison, WI, USA
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4
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DeRuisseau LR, Receno CN, Cunningham C, Bates ML, Goodell M, Liang C, Eassa B, Pascolla J, DeRuisseau KC. Breathing and Oxygen Carrying Capacity in Ts65Dn and Down Syndrome. FUNCTION 2023; 4:zqad058. [PMID: 37954975 PMCID: PMC10634617 DOI: 10.1093/function/zqad058] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 11/14/2023] Open
Abstract
Individuals with Down syndrome (Ds) are at increased risk of respiratory infection, aspiration pneumonia, and apnea. The Ts65Dn mouse is a commonly used model of Ds, but there have been no formal investigations of awake breathing and respiratory muscle function in these mice. We hypothesized that breathing would be impaired in Ts65Dn vs. wild-type (WT), and would be mediated by both neural and muscular inputs. Baseline minute ventilation was not different at 3, 6, or 12 mo of age. However, VT/Ti, a marker of the neural drive to breathe, was lower in Ts65Dn vs. WT and central apneas were more prevalent. The response to breathing hypoxia was not different, but the response to hypercapnia was attenuated, revealing a difference in carbon dioxide sensing, and/or motor output in Ts65Dn. Oxygen desaturations were present in room air, demonstrating that ventilation may not be sufficient to maintain adequate oxygen saturation in Ts65Dn. We observed no differences in arterial PO2 or PCO2, but Ts65Dn had lower hemoglobin and hematocrit. A retrospective medical record review of 52,346 Ds and 52,346 controls confirmed an elevated relative risk of anemia in Ds. We also performed eupneic in-vivo electromyography and in-vitro muscle function and histological fiber typing of the diaphragm, and found no difference between strains. Overall, conscious respiration is impaired in Ts65Dn, is mediated by neural mechanisms, and results in reduced hemoglobin saturation. Oxygen carrying capacity is reduced in Ts65Dn vs. WT, and we demonstrate that individuals with Ds are also at increased risk of anemia.
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Affiliation(s)
- Lara R DeRuisseau
- Department of Basic Sciences, University of Health Sciences and Pharmacy, St. Louis, MO 63110, USA
| | - Candace N Receno
- Department of Exercise Science and Athletic Training, Ithaca College, Ithaca, NY 14850, USA
| | - Caitlin Cunningham
- Department of Statistics, Mathematics and Computer Science, Le Moyne College, Syracuse, NY 13214, USA
| | - Melissa L Bates
- Departments of Health and Human Physiology, Internal Medicine, and the Stead Family Department of Pediatrics, University of Iowa, Iowa City, IA 52242, USA
| | - Morgan Goodell
- Lake Erie College of Osteopathic Medicine, Elmira, NY 14901, USA
| | - Chen Liang
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY 14642,USA
| | - Brianna Eassa
- Department of Biological Sciences, Le Moyne College, Syracuse, NY 13214, USA
| | - Jessica Pascolla
- Department of Basic Sciences, University of Health Sciences and Pharmacy, St. Louis, MO 63110, USA
| | - Keith C DeRuisseau
- Department of Basic Sciences, University of Health Sciences and Pharmacy, St. Louis, MO 63110, USA
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Inguscio CR, Lacavalla MA, Cisterna B, Zancanaro C, Malatesta M. Physical Training Chronically Stimulates the Motor Neuron Cell Nucleus in the Ts65Dn Mouse, a Model of Down Syndrome. Cells 2023; 12:1488. [PMID: 37296609 PMCID: PMC10252427 DOI: 10.3390/cells12111488] [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: 04/20/2023] [Revised: 05/20/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023] Open
Abstract
Down syndrome (DS) is a genetically-based disease based on the trisomy of chromosome 21 (Hsa21). DS is characterized by intellectual disability in association with several pathological traits among which early aging and altered motor coordination are prominent. Physical training or passive exercise were found to be useful in counteracting motor impairment in DS subjects. In this study we used the Ts65Dn mouse, a widely accepted animal model of DS, to investigate the ultrastructural architecture of the medullary motor neuron cell nucleus taken as marker of the cell functional state. Using transmission electron microscopy, ultrastructural morphometry, and immunocytochemistry we carried out a detailed investigation of possible trisomy-related alteration(s) of nuclear constituents, which are known to vary their amount and distribution as a function of nuclear activity, as well as the effect of adapted physical training upon them. Results demonstrated that trisomy per se affects nuclear constituents to a limited extent; however, adapted physical training is able to chronically stimulate pre-mRNA transcription and processing activity in motor neuron nuclei of trisomic mice, although to a lesser extent than in their euploid mates. These findings are a step towards understanding the mechanisms underlying the positive effect of physical activity in DS.
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Affiliation(s)
| | | | | | - Carlo Zancanaro
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, Strada Le Grazie 8, I-37134 Verona, Italy; (C.R.I.); (M.A.L.); (B.C.); (M.M.)
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6
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Scott-McKean JJ, Jones R, Johnson MW, Mier J, Basten IA, Stasko MR, Costa ACS. Emergence of Treadmill Running Ability and Quantitative Assessment of Gait Dynamics in Young Ts65Dn Mice: A Mouse Model for Down Syndrome. Brain Sci 2023; 13:brainsci13050743. [PMID: 37239215 DOI: 10.3390/brainsci13050743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 04/18/2023] [Accepted: 04/28/2023] [Indexed: 05/28/2023] Open
Abstract
Down syndrome (DS), which results from the complete or partial trisomy of chromosome 21 (trisomy-21), is the most common genetically defined cause of intellectual disability. Trisomy-21 also produces, or is associated with, many neurodevelopmental phenotypes and neurological comorbidities, including delays and deficits in fine and gross motor development. The Ts65Dn mouse is the most studied animal model for DS and displays the largest known subset of DS-like phenotypes. To date, however, only a small number of developmental phenotypes have been quantitatively defined in these animals. Here, we used a commercially available high-speed, video-based system to record and analyze the gait of Ts65Dn and euploid control mice. Longitudinal treadmill recordings were performed from p17 to p35. One of the main findings was the detection of genotype- and sex-dependent developmental delays in the emergence of consistent, progressive-intensity gait in Ts65Dn mice when compared to control mice. Gait dynamic analysis showed wider normalized front and hind stances in Ts65Dn mice compared to control mice, which may reflect deficits in dynamic postural balance. Ts65Dn mice also displayed statistically significant differences in the variability in several normalized gait measures, which were indicative of deficits in precise motor control in generating gait.
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Affiliation(s)
- Jonah J Scott-McKean
- Department of Macromolecular Science and Engineering, Case Western Reserve University, Cleveland, OH 44106-6090, USA
| | - Ryan Jones
- College of Medicine and Life Sciences, The University of Toledo, Toledo, OH 43606-3390, USA
- Department of Biochemistry, Case Western Reserve University, Cleveland, OH 44106-6090, USA
| | - Mark W Johnson
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106-6090, USA
| | - Joyce Mier
- Physical Therapy Program, University of Wisconsin, Madison, WI 53706-1532, USA
- Department of Biology, Case Western Reserve University, Cleveland, OH 44106-6090, USA
| | - Ines A Basten
- Psychiatric Hospital Asster, 3800 Sint-Truiden, Belgium
| | - Melissa R Stasko
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106-6090, USA
| | - Alberto C S Costa
- Department of Macromolecular Science and Engineering, Case Western Reserve University, Cleveland, OH 44106-6090, USA
- Department of Psychiatry, Case Western Reserve University, Cleveland, OH 44106-6090, USA
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7
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Tallino S, Winslow W, Bartholomew SK, Velazquez R. Temporal and brain region-specific elevations of soluble Amyloid-β 40-42 in the Ts65Dn mouse model of Down syndrome and Alzheimer's disease. Aging Cell 2022; 21:e13590. [PMID: 35290711 PMCID: PMC9009111 DOI: 10.1111/acel.13590] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/13/2022] [Accepted: 03/01/2022] [Indexed: 12/12/2022] Open
Abstract
Down syndrome (DS) is a leading cause of intellectual disability that also results in hallmark Alzheimer's disease (AD) pathologies such as amyloid beta (Aβ) plaques and hyperphosphorylated tau. The Ts65Dn mouse model is commonly used to study DS, as trisomic Ts65Dn mice carry 2/3 of the triplicated gene homologues as occur in human DS. The Ts65Dn strain also allows investigation of mechanisms common to DS and AD pathology, with many of these triplicated genes implicated in AD; for example, trisomic Ts65Dn mice overproduce amyloid precursor protein (APP), which is then processed into soluble Aβ40-42 fragments. Notably, Ts65Dn mice show alterations to the basal forebrain, which parallels the loss of function in this region observed in DS and AD patients early on in disease progression. However, a complete picture of soluble Aβ40-42 accumulation in a region-, age-, and sex-specific manner has not yet been characterized in the Ts65Dn model. Here, we show that trisomic mice accumulate soluble Aβ40-42 in the basal forebrain, frontal cortex, hippocampus, and cerebellum in an age-specific manner, with elevation in the frontal cortex and hippocampus as early as 4 months of age. Furthermore, we detected sex differences in accumulation of Aβ40-42 within the basal forebrain, with females having significantly higher Aβ40-42 at 7-8 months of age. Lastly, we show that APP expression in the basal forebrain and hippocampus inversely correlates with Aβ40-42 levels. This spatial and temporal characterization of soluble Aβ40-42 in the Ts65Dn model allows for further exploration of the role soluble Aβ plays in the progression of other AD-like pathologies in these key brain regions.
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Affiliation(s)
- Savannah Tallino
- Arizona State University‐Banner Neurodegenerative Disease Research Center at the Biodesign Institute Arizona State University Tempe Arizona USA
- School of Life Sciences Arizona State University Tempe Arizona USA
| | - Wendy Winslow
- Arizona State University‐Banner Neurodegenerative Disease Research Center at the Biodesign Institute Arizona State University Tempe Arizona USA
| | - Samantha K. Bartholomew
- Arizona State University‐Banner Neurodegenerative Disease Research Center at the Biodesign Institute Arizona State University Tempe Arizona USA
| | - Ramon Velazquez
- Arizona State University‐Banner Neurodegenerative Disease Research Center at the Biodesign Institute Arizona State University Tempe Arizona USA
- School of Life Sciences Arizona State University Tempe Arizona USA
- Arizona Alzheimer’s Consortium Phoenix Arizona USA
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Mouse models of aneuploidy to understand chromosome disorders. Mamm Genome 2021; 33:157-168. [PMID: 34719726 PMCID: PMC8913467 DOI: 10.1007/s00335-021-09930-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/20/2021] [Indexed: 12/04/2022]
Abstract
An organism or cell carrying a number of chromosomes that is not a multiple of the haploid count is in a state of aneuploidy. This condition results in significant changes in the level of expression of genes that are gained or lost from the aneuploid chromosome(s) and most cases in humans are not compatible with life. However, a few aneuploidies can lead to live births, typically associated with deleterious phenotypes. We do not understand why phenotypes arise from aneuploid syndromes in humans. Animal models have the potential to provide great insight, but less than a handful of mouse models of aneuploidy have been made, and no ideal system exists in which to study the effects of aneuploidy per se versus those of raised gene dosage. Here, we give an overview of human aneuploid syndromes, the effects on physiology of having an altered number of chromosomes and we present the currently available mouse models of aneuploidy, focusing on models of trisomy 21 (which causes Down syndrome) because this is the most common, and therefore, the most studied autosomal aneuploidy. Finally, we discuss the potential role of carrying an extra chromosome on aneuploid phenotypes, independent of changes in gene dosage, and methods by which this could be investigated further.
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9
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Cisterna B, Malatesta M, Zancanaro C, Boschi F. A computational approach to quantitatively define sarcomere dimensions and arrangement in skeletal muscle. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2021; 211:106437. [PMID: 34624632 DOI: 10.1016/j.cmpb.2021.106437] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 09/18/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND OBJECTIVE The skeletal muscle is composed of integrated tissues mainly composed of myofibers i.e., long, cylindrical syncytia, whose cytoplasm is mostly occupied by parallel myofibrils. In section, each myofibril is organized in serially end-to-end arranged sarcomeres connected by Z lines. In muscle disorders, these structural and functional units can undergo structural alterations in terms of Z-line and sarcomere lengths, as well as lateral alignment of Z-line among adjacent myofibrils. In this view, objectifying alterations of the myofibril and sarcomere architecture would provide a solid foundation for qualitative observations. In this work, specific quantitative parameters characterizing the sarcomere and myofibril arrangement were defined using a computerized analysis of ultrastructural images. METHODS computerized analysis was carried out on transmission electron microscopy pictures of the murine vastus lateralis muscle. Samples from both euploid (control) and trisomic (showing myofiber alterations) Ts65Dn mice were used. Two routines were written in MATLAB to measure specific structural parameters on sarcomeres and myofibrils. The output included the Z-line, M-line, and sarcomere lengths, the Aspect Ratio (AsR) and Curviness (Cur) sarcomere shape parameters, myofibril axis (α angle), and the H parameter (evaluation of sequence of Z-lines of adjacent myofibrils). RESULTS Both routines worked well in control (euploid) skeletal muscle yielding consistent quantitative data of sarcomere and myofibril structural organization. In comparison with euploid, trisomic muscle showed statistically significant lower Z-line length, similar M-line length, and statistically significant lower sarcomere length. Both AsR and Cur were statistically significantly lower in trisomic muscle, suggesting the sarcomere is barrel-shaped in the latter. The angle (α) distribution showed that the sarcomere axes are almost parallel in euploid muscle, while a large variability occurs in trisomic tissue. The mean value of H was significantly higher in trisomic versus euploid muscle indicating that Z-lines are not perfectly aligned in trisomic muscle. CONCLUSIONS Our procedure allowed us to accurately extract and quantify sarcomere and myofibril parameters from the high-resolution electron micrographs thereby yielding an effective tool to quantitatively define trisomy-associated muscle alterations. These results pave the way to future objective quantification of skeletal muscle changes in pathological conditions. SHORT ABSTRACT The skeletal muscle is composed of integrated tissues mainly composed of myofibers i.e., long, cylindrical syncytia, whose cytoplasm is mostly occupied by parallel myofibrils organized in serially end-to-end arranged sarcomeres. Several pieces of evidence have highlighted that in muscle disorders and diseases the sarcomere structure may be altered. Therefore, objectifying alterations of the myofibril and sarcomere architecture would provide a solid foundation for qualitative observations. A computerized analysis was carried out on transmission electron microscopy images of euploid (control) and trisomic (showing myofiber alterations) skeletal muscle. Two routines were written in MATLAB to measure nine sarcomere and myofibril structural parameters. Our computational method confirmed and expanded on previous qualitative ultrastructural findings defining several trisomy-associated skeletal muscle alterations. The proposed procedure is a potentially useful tool to quantitatively define skeletal muscle changes in pathological conditions involving the sarcomere.
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Affiliation(s)
- Barbara Cisterna
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, Verona 37134, Italy
| | - Manuela Malatesta
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, Verona 37134, Italy
| | - Carlo Zancanaro
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, Verona 37134, Italy
| | - Federico Boschi
- Department of Computer Science, University of Verona, Strada Le Grazie 15, Verona 37134, Italy.
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10
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Cisterna B, Sobolev AP, Costanzo M, Malatesta M, Zancanaro C. Combined Microscopic and Metabolomic Approach to Characterize the Skeletal Muscle Fiber of the Ts65Dn Mouse, A Model of Down Syndrome. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2020; 26:1014-1023. [PMID: 32867866 DOI: 10.1017/s143192762002437x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Down syndrome (DS) is a genetically based disease caused by triplication of chromosome 21. DS is characterized by severe muscle weakness associated with motor deficits; however, understanding the DS-associated skeletal muscle condition is limited. In this study, we used a combined methodological approach involving light and electron microscopy, as well as nuclear magnetic resonance spectroscopy metabolomics, to investigate morphology and composition of the quadriceps muscles in the Ts65Dn mouse, a model of DS, to identify structural and/or functional trisomy-associated alterations. Morphometric analysis demonstrated a larger size of myofibers in trisomic versus euploid mice; however, myofibrils were thinner and contained higher amounts of mitochondria and lipid droplets. In trisomic mice, magnetic resonance spectroscopy showed a tendency to an overall increase in muscle metabolites involved in protein synthesis. These data strongly suggest that in DS, a sarcoplasmic hypertrophy associated with myofibril loss characterizes quadriceps myofibers. In addition, large-sized mitochondria suggestive of impaired fission/fusion events, as well as metabolites modifications suggestive of decreased mitochondrial function, were found in the trisomic muscle. Albeit preliminary, the results provided by this novel approach consistently indicate structural and compositional alterations of the DS skeletal muscle, which are typical of early aging.
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Affiliation(s)
- Barbara Cisterna
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
| | - Anatoly P Sobolev
- Magnetic Resonance Laboratory "Annalaura Segre", Institute for Biological Systems, National Research Council, via Salaria km 29.300, Monterotondo, RomeI-00015, Italy
| | - Manuela Costanzo
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
| | - Manuela Malatesta
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
| | - Carlo Zancanaro
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
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11
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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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12
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Roper RJ, Goodlett CR, Martínez de Lagrán M, Dierssen M. Behavioral Phenotyping for Down Syndrome in Mice. ACTA ACUST UNITED AC 2020; 10:e79. [PMID: 32780566 DOI: 10.1002/cpmo.79] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Down syndrome (DS) is the most frequent genetic cause of intellectual disability, characterized by alterations in different behavioral symptom domains: neurodevelopment, motor behavior, and cognition. As mouse models have the potential to generate data regarding the neurological basis for the specific behavioral profile of DS, and may indicate pharmacological treatments with the potential to affect their behavioral phenotype, it is important to be able to assess disease-relevant behavioral traits in animal models in order to provide biological plausibility to the potential findings. The field is at a juncture that requires assessments that may effectively translate the findings acquired in mouse models to humans with DS. In this article, behavioral tests are described that are relevant to the domains affected in DS. A neurodevelopmental behavioral screen, the balance beam test, and the Multivariate Concentric Square Field test to assess multiple behavioral phenotypes and locomotion are described, discussing the ways to merge these findings to more fully understand cognitive strengths and weaknesses in this population. New directions for approaches to cognitive assessment in mice and humans are discussed. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Preweaning neurodevelopmental battery Basic Protocol 2: Balance beam Basic Protocol 3: Multivariate concentric square field test (MCSF).
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Affiliation(s)
| | | | - María Martínez de Lagrán
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Mara Dierssen
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,Biomedical Research Networking Center on Rare Diseases (CIBERER), Institute of Health Carlos III, Madrid, Spain
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13
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Goodlett CR, Stringer M, LaCombe J, Patel R, Wallace JM, Roper RJ. Evaluation of the therapeutic potential of Epigallocatechin-3-gallate (EGCG) via oral gavage in young adult Down syndrome mice. Sci Rep 2020; 10:10426. [PMID: 32591597 PMCID: PMC7319987 DOI: 10.1038/s41598-020-67133-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 05/29/2020] [Indexed: 01/09/2023] Open
Abstract
Epigallocatechin-3-gallate (EGCG) is a candidate therapeutic for Down syndrome (DS) phenotypes based on in vitro inhibition of DYRK1A, a triplicated gene product of Trisomy 21 (Ts21). Consumption of green tea extracts containing EGCG improved some cognitive and behavioral outcomes in DS mouse models and in humans with Ts21. In contrast, treatment with pure EGCG in DS mouse models did not improve neurobehavioral phenotypes. This study tested the hypothesis that 200 mg/kg/day of pure EGCG, given via oral gavage, would improve neurobehavioral and skeletal phenotypes in the Ts65Dn DS mouse model. Serum EGCG levels post-gavage were significantly higher in trisomic mice than in euploid mice. Daily EGCG gavage treatments over three weeks resulted in growth deficits in both euploid and trisomic mice. Compared to vehicle treatment, EGCG did not significantly improve behavioral performance of Ts65Dn mice in the multivariate concentric square field, balance beam, or Morris water maze tasks, but reduced swimming speed. Furthermore, EGCG resulted in reduced cortical bone structure and strength in Ts65Dn mice. These outcomes failed to support the therapeutic potential of EGCG, and the deleterious effects on growth and skeletal phenotypes underscore the need for caution in high-dose EGCG supplements as an intervention in DS.
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Affiliation(s)
- Charles R Goodlett
- IUPUI Department of Psychology, 402 North Blackford Street, LD 124, Indianapolis, IN, 46202-3275, USA
| | - Megan Stringer
- IUPUI Department of Psychology, 402 North Blackford Street, LD 124, Indianapolis, IN, 46202-3275, USA
| | - Jonathan LaCombe
- IUPUI Department of Biology, 723 West Michigan Street; SL 306, Indianapolis, IN, 46202-3275, USA
| | - Roshni Patel
- IUPUI Department of Biology, 723 West Michigan Street; SL 306, Indianapolis, IN, 46202-3275, USA
| | - Joseph M Wallace
- IUPUI Department of Biomedical Engineering, 723 West Michigan Street; SL 220B, Indianapolis, IN, 46202-3275, USA
| | - Randall J Roper
- IUPUI Department of Biology, 723 West Michigan Street; SL 306, Indianapolis, IN, 46202-3275, USA.
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14
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Tsuji M, Ohshima M, Yamamoto Y, Saito S, Hattori Y, Tanaka E, Taguchi A, Ihara M, Ogawa Y. Cilostazol, a Phosphodiesterase 3 Inhibitor, Moderately Attenuates Behaviors Depending on Sex in the Ts65Dn Mouse Model of Down Syndrome. Front Aging Neurosci 2020; 12:106. [PMID: 32372946 PMCID: PMC7186592 DOI: 10.3389/fnagi.2020.00106] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 03/30/2020] [Indexed: 11/16/2022] Open
Abstract
People with Down syndrome, which is a trisomy of chromosome 21, exhibit intellectual disability from infancy and neuropathology similar to Alzheimer’s disease, such as amyloid plaques, from an early age. Recently, we showed that cilostazol, a selective inhibitor of phosphodiesterase (PDE) 3, promotes the clearance of amyloid β and rescues cognitive deficits in a mouse model of Alzheimer’s disease. The objective of the present study was to examine whether cilostazol improves behaviors in the most widely used animal model of Down syndrome, i.e., Ts65Dn mice. Mice were supplemented with cilostazol from the fetal period until young adulthood. Supplementation significantly ameliorated novel-object recognition in Ts65Dn females and partially ameliorated sensorimotor function as determined by the rotarod test in Ts65Dn females and hyperactive locomotion in Ts65Dn males. Cilostazol supplementation significantly shortened swimming distance in Ts65Dn males in the Morris water maze test, suggesting that the drug improved cognitive function, although it did not shorten swimming duration, which was due to decreased swimming speed. Thus, this study suggests that early supplementation with cilostazol partially rescues behavioral abnormalities seen in Down syndrome and indicates that the effects are sex-dependent.
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Affiliation(s)
- Masahiro Tsuji
- Department of Regenerative Medicine and Tissue Engineering, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Makiko Ohshima
- Department of Regenerative Medicine and Tissue Engineering, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Yumi Yamamoto
- Department of Regenerative Medicine and Tissue Engineering, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Satoshi Saito
- Department of Regenerative Medicine and Tissue Engineering, National Cerebral and Cardiovascular Center, Osaka, Japan.,Department of Neurology, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Yorito Hattori
- Department of Neurology, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Emi Tanaka
- Department of Regenerative Medicine and Tissue Engineering, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Akihiko Taguchi
- Department of Regenerative Medicine Research, Institute of Biomedical Research and Innovation, Kobe, Japan
| | - Masafumi Ihara
- Department of Neurology, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Yuko Ogawa
- Department of Regenerative Medicine and Tissue Engineering, National Cerebral and Cardiovascular Center, Osaka, Japan
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15
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Martínez de Lagrán M. Mapping behavioral landscapes in Down syndrome animal models. PROGRESS IN BRAIN RESEARCH 2020; 251:145-179. [DOI: 10.1016/bs.pbr.2020.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Hamlett ED, Ledreux A, Gilmore A, Vazey EM, Aston-Jones G, Boger HA, Paredes D, Granholm ACE. Inhibitory designer receptors aggravate memory loss in a mouse model of down syndrome. Neurobiol Dis 2019; 134:104616. [PMID: 31678403 DOI: 10.1016/j.nbd.2019.104616] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 08/06/2019] [Accepted: 09/17/2019] [Indexed: 12/20/2022] Open
Abstract
The pontine nucleus locus coeruleus (LC) is the primary source of noradrenergic (NE) projections to the brain and is important for working memory, attention, and cognitive flexibility. Individuals with Down syndrome (DS) develop Alzheimer's disease (AD) with high penetrance and often exhibit working memory deficits coupled with degeneration of LC-NE neurons early in the progression of AD pathology. Designer receptors exclusively activated by designer drugs (DREADDs) are chemogenetic tools that allow targeted manipulation of discrete neuronal populations in the brain without the confounds of off-target effects. We utilized male Ts65Dn mice (a mouse model for DS), and male normosomic (NS) controls to examine the effects of inhibitory DREADDs delivered via an AAV vector under translational control of the synthetic PRSx8, dopamine β hydroxylase (DβH) promoter. This chemogenetic tool allowed LC inhibition upon administration of the inert DREADD ligand, clozapine-N-oxide (CNO). DREADD-mediated LC inhibition impaired performance in a novel object recognition task and reversal learning in a spatial task. DREADD-mediated LC inhibition gave rise to an elevation of α-adrenoreceptors both in NS and in Ts65Dn mice. Further, microglial markers showed that the inhibitory DREADD stimulation led to increased microglial activation in the hippocampus in Ts65Dn but not in NS mice. These findings strongly suggest that LC signaling is important for intact memory and learning in Ts65Dn mice and disruption of these neurons leads to increased inflammation and dysregulation of adrenergic receptors.
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Affiliation(s)
- Eric D Hamlett
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC 29425, USA.
| | - Aurélie Ledreux
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA
| | - Anah Gilmore
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA
| | - Elena M Vazey
- Department of Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Gary Aston-Jones
- Rutgers Brain Health Institute, Rutgers University, Piscataway, NJ 08854, USA
| | - Heather A Boger
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Daniel Paredes
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA
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17
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Roper RJ, Hawley L, Goodlett CR. Influence of allelic differences in Down syndrome. PROGRESS IN BRAIN RESEARCH 2019; 251:29-54. [PMID: 32057311 PMCID: PMC7500172 DOI: 10.1016/bs.pbr.2019.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Both trisomic and non-trisomic genes may affect the incidence and severity of phenotypes associated with Down syndrome (DS). The importance of extra (trisomic) genetic material is emphasized in DS, with less emphasis to the allelic composition of candidate trisomic genes in defining the trisomic gene-phenotype relationship in DS. Allelic differences in non-trisomic genes have been shown to be important moderators of cardiac, leukemia, and developmental phenotypes associated with DS. Trisomic mouse models provide an in vivo genetic platform for examining the gene-phenotype relationship, including the influence of allelic variants, on DS-like phenotypes. DS mouse models have differing trisomic genetic makeup, and optimal development, viability and translational value of these mouse models may require a non-inbred genetic background with heterogeneity at many loci. Additionally, understanding the contribution of specific genes or regions to DS phenotypes often requires the utilization of genetically manipulated mice that may be established on a different inbred background than the trisomic mice. The impact of allelic differences of trisomic and background genes in human and model systems may offer insight into the variability in occurrence and severity of trisomic phenotypes.
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Affiliation(s)
- Randall J Roper
- Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis, IN, United States.
| | - Laura Hawley
- Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis, IN, United States
| | - Charles R Goodlett
- Department of Psychology, Indiana University-Purdue University Indianapolis, Indianapolis, IN, United States
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18
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Hamlett ED, LaRosa A, Mufson EJ, Fortea J, Ledreux A, Granholm AC. Exosome release and cargo in Down syndrome. Dev Neurobiol 2019; 79:639-655. [PMID: 31347291 DOI: 10.1002/dneu.22712] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/20/2019] [Accepted: 07/22/2019] [Indexed: 12/11/2022]
Abstract
Down syndrome (DS) is a multisystem disorder affecting 1 in 800 births worldwide. Advancing technology, medical treatment, and social intervention have dramatically increased life expectancy, yet there are many etiologies of this disorder that are in need of further research. The advent of the ability to capture extracellular vesicles (EVs) in blood from specific cell types allows for the investigation of novel intracellular processes. Exosomes are one type of EVs that have demonstrated great potential in uncovering new biomarkers of neurodegeneration and disease, and also that appear to be intricately involved in the transsynaptic spread of pathogenic factors underlying Alzheimer's disease and other neurological diseases. Exosomes are nanosized vesicles, generated in endosomal multivesicular bodies (MVBs) and secreted by most cells in the body. Since exosomes are important mediators of intercellular communication and genetic exchange, they have emerged as a major research focus and have revealed novel biological sequelae involved in conditions afflicting the DS population. This review summarizes current knowledge on exosome biology in individuals with DS, both early in life and in aging individuals. Collectively these studies have demonstrated that complex multicellular processes underlying DS etiologies may include abnormal formation and secretion of extracellular vesicles such as exosomes.
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Affiliation(s)
- Eric D Hamlett
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Angela LaRosa
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina
| | - Elliott J Mufson
- Department of Neurobiology and Neurology, Barrow Neurological Institute, Phoenix, Arizona
| | - Juan Fortea
- Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Biomedical Research Institute Sant Pau, CIBERNED, Universitat Autònoma de Barcelona, Barcelona, Spain.,Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Institut d'Investigació Biomèdica August Pi i Sunyer, University of Barcelona, Barcelona, Spain
| | - Aurélie Ledreux
- Department of Biological Sciences and the Knoebel Institute for Healthy Aging, University of Denver, Denver, Colorado
| | - Ann-Charlotte Granholm
- Department of Biological Sciences and the Knoebel Institute for Healthy Aging, University of Denver, Denver, Colorado
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19
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Lauterborn JC, Schultz MN, Le AA, Amani M, Friedman AE, Leach PT, Gall CM, Lynch GS, Crawley JN. Spaced training improves learning in Ts65Dn and Ube3a mouse models of intellectual disabilities. Transl Psychiatry 2019; 9:166. [PMID: 31182707 PMCID: PMC6557858 DOI: 10.1038/s41398-019-0495-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 03/14/2019] [Accepted: 03/23/2019] [Indexed: 12/29/2022] Open
Abstract
Benefits of distributed learning strategies have been extensively described in the human literature, but minimally investigated in intellectual disability syndromes. We tested the hypothesis that training trials spaced apart in time could improve learning in two distinct genetic mouse models of neurodevelopmental disorders characterized by intellectual impairments. As compared to training with massed trials, spaced training significantly improved learning in both the Ts65Dn trisomy mouse model of Down syndrome and the maternally inherited Ube3a mutant mouse model of Angelman syndrome. Spacing the training trials at 1 h intervals accelerated acquisition of three cognitive tasks by Ts65Dn mice: (1) object location memory, (2) novel object recognition, (3) water maze spatial learning. Further, (4) spaced training improved water maze spatial learning by Ube3a mice. In contrast, (5) cerebellar-mediated rotarod motor learning was not improved by spaced training. Corroborations in three assays, conducted in two model systems, replicated within and across two laboratories, confirm the strength of the findings. Our results indicate strong translational relevance of a behavioral intervention strategy for improving the standard of care in treating the learning difficulties that are characteristic and clinically intractable features of many neurodevelopmental disorders.
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Affiliation(s)
- J C Lauterborn
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - M N Schultz
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
| | - A A Le
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - M Amani
- Department of Psychiatry and Human Behavior, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
- Department of Physiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - A E Friedman
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
- Harvard University, Cambridge, MA, USA
| | - P T Leach
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
- Biogen Inc., Cambridge, MA, USA
| | - C M Gall
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - G S Lynch
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
- Department of Psychiatry and Human Behavior, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - J N Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA.
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20
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Glass TJ, Twadell SL, Valmadrid LC, Connor NP. Early impacts of modified food consistency on oromotor outcomes in mouse models of Down syndrome. Physiol Behav 2018; 199:273-281. [PMID: 30496741 DOI: 10.1016/j.physbeh.2018.11.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 10/16/2018] [Accepted: 11/25/2018] [Indexed: 12/12/2022]
Abstract
Down syndrome (DS) in humans is associated with differences of the central nervous system and oromotor development. DS also increases risks for pediatric feeding challenges, which sometimes involve the use of altered food consistencies. Therefore, experimental food consistency paradigms are of interest to oromotor investigations in mouse models of Down syndrome (DS). The present work reports impacts of an altered food consistency paradigm on the Ts65Dn and Dp(16)1Yey mouse models of DS, and sibling control mice. At weaning, Ts65Dn, Dp(16)1Yey and respective controls were assigned to receive either a hard food or a soft food (eight experimental groups, n = 8-10 per group). Two weeks later, mice were assessed for mastication speeds and then euthanized for muscle analysis. Soft food conditions were associated with significantly smaller weight gain (p = .003), significantly less volitional water intake through licking (p = .0001), and significant reductions in size of anterior digastric myofibers positive for myosin heavy chain isoform (MyHC) 2b (p = .049). Genotype was associated with significant differences in weight gain (p = .004), significant differences in mastication rate (p = .001), significant differences in a measure of anterior digastric muscle size (p = .03), and significant reductions in size of anterior digastric myofibers positive for MyHC 2a (p = .04). In multiple measures, the Ts65Dn model of DS was more affected than other genotype groups. Findings indicate a soft food consistency condition in mice is associated with significant reductions in weight gain and oromotor activity, and may impact digastric muscle. This suggests extended periods of food consistency modifications may have impacts that extend beyond their immediate roles in facilitating deglutition.
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Affiliation(s)
- Tiffany J Glass
- Department of Surgery, University of Wisconsin, Madison, WI, USA.
| | - Sara L Twadell
- Department of Surgery, University of Wisconsin, Madison, WI, USA
| | - Luke C Valmadrid
- Department of Surgery, University of Wisconsin, Madison, WI, USA
| | - Nadine P Connor
- Department of Surgery, University of Wisconsin, Madison, WI, USA; Department of Communication Sciences and Disorders, University of Wisconsin, Madison, WI, USA
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21
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Leach PT, Crawley JN. Touchscreen learning deficits in Ube3a, Ts65Dn and Mecp2 mouse models of neurodevelopmental disorders with intellectual disabilities. GENES, BRAIN, AND BEHAVIOR 2018; 17:e12452. [PMID: 29266714 PMCID: PMC6013336 DOI: 10.1111/gbb.12452] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/29/2017] [Accepted: 12/16/2017] [Indexed: 12/25/2022]
Abstract
Mutant mouse models of neurodevelopmental disorders with intellectual disabilities provide useful translational research tools, especially in cases where robust cognitive deficits are reproducibly detected. However, motor, sensory and/or health issues consequent to the mutation may introduce artifacts that preclude testing in some standard cognitive assays. Touchscreen learning and memory tasks in small operant chambers have the potential to circumvent these confounds. Here we use touchscreen visual discrimination learning to evaluate performance in the maternally derived Ube3a mouse model of Angelman syndrome, the Ts65Dn trisomy mouse model of Down syndrome, and the Mecp2Bird mouse model of Rett syndrome. Significant deficits in acquisition of a 2-choice visual discrimination task were detected in both Ube3a and Ts65Dn mice. Procedural control measures showed no genotype differences during pretraining phases or during acquisition. Mecp2 males did not survive long enough for touchscreen training, consistent with previous reports. Most Mecp2 females failed on pretraining criteria. Significant impairments on Morris water maze spatial learning were detected in both Ube3a and Ts65Dn, replicating previous findings. Abnormalities on rotarod in Ube3a, and on open field in Ts65Dn, replicating previous findings, may have contributed to the observed acquisition deficits and swim speed abnormalities during water maze performance. In contrast, these motor phenotypes do not appear to have affected touchscreen procedural abilities during pretraining or visual discrimination training. Our findings of slower touchscreen learning in 2 mouse models of neurodevelopmental disorders with intellectual disabilities indicate that operant tasks offer promising outcome measures for the preclinical discovery of effective pharmacological therapeutics.
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Affiliation(s)
- P T Leach
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
| | - J N Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
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22
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Giacomini A, Stagni F, Emili M, Guidi S, Salvalai ME, Grilli M, Vidal-Sanchez V, Martinez-Cué C, Bartesaghi R. Treatment with corn oil improves neurogenesis and cognitive performance in the Ts65Dn mouse model of Down syndrome. Brain Res Bull 2018; 140:378-391. [PMID: 29935232 DOI: 10.1016/j.brainresbull.2018.06.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/07/2018] [Accepted: 06/18/2018] [Indexed: 12/12/2022]
Abstract
Individuals with Down syndrome (DS), a genetic condition due to triplication of Chromosome 21, are characterized by intellectual disability that worsens with age. Since impairment of neurogenesis and dendritic maturation are very likely key determinants of intellectual disability in DS, interventions targeted to these defects may translate into a behavioral benefit. While most of the neurogenesis enhancers tested so far in DS mouse models may pose some caveats due to possible side effects, substances naturally present in the human diet may be regarded as therapeutic tools with a high translational impact. Linoleic acid and oleic acid are major constituents of corn oil that positively affect neurogenesis and neuron maturation. Based on these premises, the goal of the current study was to establish whether treatment with corn oil improves hippocampal neurogenesis and hippocampus-dependent memory in the Ts65Dn model of DS. Four-month-old Ts65Dn and euploid mice were treated with saline or corn oil for 30 days. Evaluation of behavior at the end of treatment showed that Ts65Dn mice treated with corn oil underwent a large improvement in hippocampus-dependent learning and memory. Evaluation of neurogenesis and dendritogenesis showed that in treated Ts65Dn mice the number of new granule cells of the hippocampal dentate gyrus and their dendritic pattern became similar to those of euploid mice. In addition, treated Ts65Dn mice underwent an increase in body and brain weight. This study shows for the first time that fatty acids have a positive impact on the brain of the Ts65Dn mouse model of DS. These results suggest that a diet that is rich in fatty acids may exert beneficial effects on cognitive performance in individuals with DS without causing adverse effects.
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Affiliation(s)
- Andrea Giacomini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Fiorenza Stagni
- 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
| | - Maria Elisa Salvalai
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Novara, Italy
| | - Mariagrazia Grilli
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Novara, Italy
| | - Veronica Vidal-Sanchez
- Department of Physiology and Pharmacology, School of Medicine, University of Cantabria, Santander, Spain
| | - Carmen Martinez-Cué
- Department of Physiology and Pharmacology, School of Medicine, University of Cantabria, Santander, Spain
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
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Aziz NM, Guedj F, Pennings JLA, Olmos-Serrano JL, Siegel A, Haydar TF, Bianchi DW. Lifespan analysis of brain development, gene expression and behavioral phenotypes in the Ts1Cje, Ts65Dn and Dp(16)1/Yey mouse models of Down syndrome. Dis Model Mech 2018; 11:dmm031013. [PMID: 29716957 PMCID: PMC6031353 DOI: 10.1242/dmm.031013] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 04/23/2018] [Indexed: 12/26/2022] Open
Abstract
Down syndrome (DS) results from triplication of human chromosome 21. Neuropathological hallmarks of DS include atypical central nervous system development that manifests prenatally and extends throughout life. As a result, individuals with DS exhibit cognitive and motor deficits, and have delays in achieving developmental milestones. To determine whether different mouse models of DS recapitulate the human prenatal and postnatal phenotypes, here, we directly compared brain histogenesis, gene expression and behavior over the lifespan of three cytogenetically distinct mouse models of DS: Ts1Cje, Ts65Dn and Dp(16)1/Yey. Histological data indicated that Ts65Dn mice were the most consistently affected with respect to somatic growth, neurogenesis and brain morphogenesis. Embryonic and adult gene expression results showed that Ts1Cje and Ts65Dn brains had considerably more differentially expressed (DEX) genes compared with Dp(16)1/Yey mice, despite the larger number of triplicated genes in the latter model. In addition, DEX genes showed little overlap in identity and chromosomal distribution in the three models, leading to dissimilarities in affected functional pathways. Perinatal and adult behavioral testing also highlighted differences among the models in their abilities to achieve various developmental milestones and perform hippocampal- and motor-based tasks. Interestingly, Dp(16)1/Yey mice showed no abnormalities in prenatal brain phenotypes, yet they manifested behavioral deficits starting at postnatal day 15 that continued through adulthood. In contrast, Ts1Cje mice showed mildly abnormal embryonic brain phenotypes, but only select behavioral deficits as neonates and adults. Altogether, our data showed widespread and unexpected fundamental differences in behavioral, gene expression and brain development phenotypes between these three mouse models. Our findings illustrate unique limitations of each model when studying aspects of brain development and function in DS. This work helps to inform model selection in future studies investigating how observed neurodevelopmental abnormalities arise, how they contribute to cognitive impairment, and when testing therapeutic molecules to ameliorate the intellectual disability associated with DS.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Nadine M Aziz
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Faycal Guedj
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jeroen L A Pennings
- Center for Health Protection, National Institute for Public Health and the Environment, 3720 BA Bilthoven, The Netherlands
| | - Jose Luis Olmos-Serrano
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Ashley Siegel
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tarik F Haydar
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Diana W Bianchi
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Pharmacological Modulation of Three Modalities of CA1 Hippocampal Long-Term Potentiation in the Ts65Dn Mouse Model of Down Syndrome. Neural Plast 2018; 2018:9235796. [PMID: 29849573 PMCID: PMC5914153 DOI: 10.1155/2018/9235796] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 03/15/2018] [Indexed: 02/02/2023] Open
Abstract
The Ts65Dn mouse is the most studied animal model of Down syndrome. Past research has shown a significant reduction in CA1 hippocampal long-term potentiation (LTP) induced by theta-burst stimulation (TBS), but not in LTP induced by high-frequency stimulation (HFS), in slices from Ts65Dn mice compared with euploid mouse-derived slices. Additionally, therapeutically relevant doses of the drug memantine were shown to rescue learning and memory deficits in Ts65Dn mice. Here, we observed that 1 μM memantine had no detectable effect on HFS-induced LTP in either Ts65Dn- or control-derived slices, but it rescued TBS-induced LTP in Ts65Dn-derived slices to control euploid levels. Then, we assessed LTP induced by four HFS (4xHFS) and found that this form of LTP was significantly depressed in Ts65Dn slices when compared with LTP in euploid control slices. Memantine, however, did not rescue this phenotype. Because 4xHFS-induced LTP had not yet been characterized in Ts65Dn mice, we also investigated the effects of picrotoxin, amyloid beta oligomers, and soluble recombinant human prion protein (rPrP) on this form of LTP. Whereas ≥10 μM picrotoxin increased LTP to control levels, it also caused seizure-like oscillations. Neither amyloid beta oligomers nor rPrP had any effect on 4xHFS-induced LTP in Ts65Dn-derived slices.
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25
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From altered synaptic plasticity to atypical learning: A computational model of Down syndrome. Cognition 2018; 171:15-24. [DOI: 10.1016/j.cognition.2017.10.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 10/23/2017] [Accepted: 10/25/2017] [Indexed: 01/09/2023]
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Stagni F, Giacomini A, Guidi S, Emili M, Uguagliati B, Salvalai ME, Bortolotto V, Grilli M, Rimondini R, Bartesaghi R. A flavonoid agonist of the TrkB receptor for BDNF improves hippocampal neurogenesis and hippocampus-dependent memory in the Ts65Dn mouse model of DS. Exp Neurol 2017; 298:79-96. [DOI: 10.1016/j.expneurol.2017.08.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 08/24/2017] [Accepted: 08/31/2017] [Indexed: 12/31/2022]
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Kazim SF, Blanchard J, Bianchi R, Iqbal K. Early neurotrophic pharmacotherapy rescues developmental delay and Alzheimer's-like memory deficits in the Ts65Dn mouse model of Down syndrome. Sci Rep 2017; 7:45561. [PMID: 28368015 PMCID: PMC5377379 DOI: 10.1038/srep45561] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 02/27/2017] [Indexed: 12/21/2022] Open
Abstract
Down syndrome (DS), caused by trisomy 21, is the most common genetic cause of intellectual disability and is associated with a greatly increased risk of early-onset Alzheimer’s disease (AD). The Ts65Dn mouse model of DS exhibits several key features of the disease including developmental delay and AD-like cognitive impairment. Accumulating evidence suggests that impairments in early brain development caused by trisomy 21 contribute significantly to memory deficits in adult life in DS. Prenatal genetic testing to diagnose DS in utero, provides the novel opportunity to initiate early pharmacological treatment to target this critical period of brain development. Here, we report that prenatal to early postnatal treatment with a ciliary neurotrophic factor (CNTF) small-molecule peptide mimetic, Peptide 021 (P021), rescued developmental delay in pups and AD-like hippocampus-dependent memory impairments in adult life in Ts65Dn mice. Furthermore, this treatment prevented pre-synaptic protein deficit, decreased glycogen synthase kinase-3beta (GSK3β) activity, and increased levels of synaptic plasticity markers including brain derived neurotrophic factor (BNDF) and phosphorylated CREB, both in young (3-week-old) and adult (~ 7-month-old) Ts65Dn mice. These findings provide novel evidence that providing neurotrophic support during early brain development can prevent developmental delay and AD-like memory impairments in a DS mouse model.
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Affiliation(s)
- Syed Faraz Kazim
- Department of Neurochemistry, and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR), Staten Island, NY 10314, USA.,The Robert F. Furchgott Center for Neural and Behavioral Science, and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center, Brooklyn, NY 11203, USA.,Graduate Program in Neural and Behavioral Science, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA
| | - Julie Blanchard
- Department of Neurochemistry, and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR), Staten Island, NY 10314, USA
| | - Riccardo Bianchi
- The Robert F. Furchgott Center for Neural and Behavioral Science, and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center, Brooklyn, NY 11203, USA
| | - Khalid Iqbal
- Department of Neurochemistry, and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR), Staten Island, NY 10314, USA
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Abstract
Studies in humans with Down syndrome (DS) show that alterations in fetal brain development are followed by postnatal deficits in neuronal numbers, synaptic plasticity, and cognitive and motor function. This same progression is replicated in several mouse models of DS. Dp(16)1Yey/+ (hereafter called Dp16) is a recently developed mouse model of DS in which the entire region of mouse chromosome 16 that is homologous to human chromosome 21 has been triplicated. As such, Dp16 mice may more closely reproduce neurodevelopmental changes occurring in humans with DS. Here, we present the first comprehensive cellular and behavioral study of the Dp16 forebrain from embryonic to adult stages. Unexpectedly, our results demonstrate that Dp16 mice do not have prenatal brain defects previously reported in human fetal neocortex and in the developing forebrains of other mouse models, including microcephaly, reduced neurogenesis, and abnormal cell proliferation. Nevertheless, we found impairments in postnatal developmental milestones, fewer inhibitory forebrain neurons, and deficits in motor and cognitive performance in Dp16 mice. Therefore, although this new model does not express prenatal morphological phenotypes associated with DS, abnormalities in the postnatal period appear sufficient to produce significant cognitive deficits in Dp16.
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Glass TJ, Connor NP. Digastric Muscle Phenotypes of the Ts65Dn Mouse Model of Down Syndrome. PLoS One 2016; 11:e0158008. [PMID: 27336944 PMCID: PMC4919106 DOI: 10.1371/journal.pone.0158008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 06/08/2016] [Indexed: 12/18/2022] Open
Abstract
Down syndrome is frequently associated with complex difficulties in oromotor development, feeding, and swallowing. However, the muscle phenotypes underlying these deficits are unclear. We tested the hypotheses that the Ts65Dn mouse model of DS has significantly altered myosin heavy chain (MyHC) isoform profiles of the muscles involved in feeding and swallowing, as well as reductions in the speed of these movements during behavioral assays. SDS-PAGE, immunofluorescence, and qRT-PCR were used to assess MyHC isoform expression in pertinent muscles, and functional feeding and swallowing performance were quantified through videofluoroscopy and mastication assays. We found that both the anterior digastric (ADG) and posterior digastric (PDG) muscles in 11-day old and 5–6 week old Ts65Dn groups showed significantly lower MyHC 2b protein levels than in age-matched euploid control groups. In videofluoroscopic and videotape assays used to quantify swallowing and mastication performance, 5–6 week old Ts65Dn and euploid controls showed similar swallow rates, inter-swallow intervals, and mastication rates. In analysis of adults, 10–11 week old Ts65Dn mice revealed significantly less MyHC 2b mRNA expression in the posterior digastric, but not the anterior digastric muscle as compared with euploid controls. Analysis of MyHC 2b protein levels across an adult age range (10–53 weeks of age) revealed lower levels of MyHC 2b protein in the PDG of Ts65Dn than in euploids, but similar levels of MyHC 2b in the ADG. Cumulatively, these results indicate biochemical differences in some, but not all, muscles involved in swallowing and jaw movement in Ts65Dn mice that manifest early in post-natal development, and persist into adulthood. These findings suggest potential utility of this model for future investigations of the mechanisms of oromotor difficulties associated with Down syndrome.
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Affiliation(s)
- Tiffany J. Glass
- Department of Surgery, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail:
| | - Nadine P. Connor
- Department of Surgery, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Communication Sciences and Disorders, University of Wisconsin, Madison, Wisconsin, United States of America
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Sansevero G, Begenisic T, Mainardi M, Sale A. Experience-dependent reduction of soluble β-amyloid oligomers and rescue of cognitive abilities in middle-age Ts65Dn mice, a model of Down syndrome. Exp Neurol 2016; 283:49-56. [PMID: 27288239 DOI: 10.1016/j.expneurol.2016.06.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 05/30/2016] [Accepted: 06/06/2016] [Indexed: 11/17/2022]
Abstract
Down syndrome (DS) is the most diffused genetic cause of intellectual disability and, after the age of forty, is invariantly associated with Alzheimer's disease (AD). In the last years, the prolongation of life expectancy in people with DS renders the need for intervention paradigms aimed at improving mental disability and counteracting AD pathology particularly urgent. At present, however, there are no effective therapeutic strategies for DS and concomitant AD in mid-life people. The most intensively studied mouse model of DS is the Ts65Dn line, which summarizes the main hallmarks of the DS phenotype, included severe learning and memory deficits and age-dependent AD-like pathology. Here we report for the first time that middle-age Ts65Dn mice display a marked increase in soluble Aβ oligomer levels in their hippocampus. Moreover, we found that long-term exposure to environmental enrichment (EE), a widely used paradigm that increases sensory-motor stimulation, reduces Aβ oligomers and rescues spatial memory abilities in trisomic mice. Our findings underscore the potential of EE procedures as a non-invasive paradigm for counteracting brain aging processes in DS subjects.
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Affiliation(s)
- Gabriele Sansevero
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy; NEUROFARBA, University of Florence, Florence, Italy
| | - Tatjana Begenisic
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy
| | - Marco Mainardi
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy
| | - Alessandro Sale
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy.
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Hamlett ED, Boger HA, Ledreux A, Kelley CM, Mufson EJ, Falangola MF, Guilfoyle DN, Nixon RA, Patterson D, Duval N, Granholm ACE. Cognitive Impairment, Neuroimaging, and Alzheimer Neuropathology in Mouse Models of Down Syndrome. Curr Alzheimer Res 2016; 13:35-52. [PMID: 26391050 PMCID: PMC5034871 DOI: 10.2174/1567205012666150921095505] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 08/08/2015] [Accepted: 08/20/2015] [Indexed: 11/22/2022]
Abstract
Down syndrome (DS) is the most common non-lethal genetic condition that affects approximately 1 in 700 births in the United States of America. DS is characterized by complete or segmental chromosome 21 trisomy, which leads to variable intellectual disabilities, progressive memory loss, and accelerated neurodegeneration with age. During the last three decades, people with DS have experienced a doubling of life expectancy due to progress in treatment of medical comorbidities, which has allowed this population to reach the age when they develop early onset Alzheimer's disease (AD). Individuals with DS develop cognitive and pathological hallmarks of AD in their fourth or fifth decade, and are currently lacking successful prevention or treatment options for dementia. The profound memory deficits associated with DS-related AD (DS-AD) have been associated with degeneration of several neuronal populations, but mechanisms of neurodegeneration are largely unexplored. The most successful animal model for DS is the Ts65Dn mouse, but several new models have also been developed. In the current review, we discuss recent findings and potential treatment options for the management of memory loss and AD neuropathology in DS mouse models. We also review agerelated neuropathology, and recent findings from neuroimaging studies. The validation of appropriate DS mouse models that mimic neurodegeneration and memory loss in humans with DS can be valuable in the study of novel preventative and treatment interventions, and may be helpful in pinpointing gene-gene interactions as well as specific gene segments involved in neurodegeneration.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Ann-Charlotte E Granholm
- Department Neurosciences, Director, Center on Aging, Medical Univ. South Carolina, Basic Science Bldg, Room 403, 173 Ashley Avenue, Charleston, SC 29425, USA.
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32
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Choong XY, Tosh JL, Pulford LJ, Fisher EMC. Dissecting Alzheimer disease in Down syndrome using mouse models. Front Behav Neurosci 2015; 9:268. [PMID: 26528151 PMCID: PMC4602094 DOI: 10.3389/fnbeh.2015.00268] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 09/21/2015] [Indexed: 11/13/2022] Open
Abstract
Down syndrome (DS) is a common genetic condition caused by the presence of three copies of chromosome 21 (trisomy 21). This greatly increases the risk of Alzheimer disease (AD), but although virtually all people with DS have AD neuropathology by 40 years of age, not all develop dementia. To dissect the genetic contribution of trisomy 21 to DS phenotypes including those relevant to AD, a range of DS mouse models has been generated which are trisomic for chromosome segments syntenic to human chromosome 21. Here, we consider key characteristics of human AD in DS (AD-DS), and our current state of knowledge on related phenotypes in AD and DS mouse models. We go on to review important features needed in future models of AD-DS, to understand this type of dementia and so highlight pathogenic mechanisms relevant to all populations at risk of AD.
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Affiliation(s)
- Xun Yu Choong
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
| | - Justin L Tosh
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
| | - Laura J Pulford
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
| | - Elizabeth M C Fisher
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
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Jiang X, Liu C, Yu T, Zhang L, Meng K, Xing Z, Belichenko PV, Kleschevnikov AM, Pao A, Peresie J, Wie S, Mobley WC, Yu YE. Genetic dissection of the Down syndrome critical region. Hum Mol Genet 2015; 24:6540-51. [PMID: 26374847 DOI: 10.1093/hmg/ddv364] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 09/02/2015] [Indexed: 01/11/2023] Open
Abstract
Down syndrome (DS), caused by trisomy 21, is the most common chromosomal disorder associated with developmental cognitive deficits. Despite intensive efforts, the genetic mechanisms underlying developmental cognitive deficits remain poorly understood, and no treatment has been proven effective. The previous mouse-based experiments suggest that the so-called Down syndrome critical region of human chromosome 21 is an important region for this phenotype, which is demarcated by Setd4/Cbr1 and Fam3b/Mx2. We first confirmed the importance of the Cbr1-Fam3b region using compound mutant mice, which carry a duplication spanning the entire human chromosome 21 orthologous region on mouse chromosome 16 [Dp(16)1Yey] and Ms1Rhr. By dividing the Setd4-Mx2 region into complementary Setd4-Kcnj6 and Kcnj15-Mx2 intervals, we started an unbiased dissection through generating and analyzing Dp(16)1Yey/Df(16Setd4-Kcnj6)Yey and Dp(16)1Yey/Df(16Kcnj15-Mx2)Yey mice. Surprisingly, the Dp(16)1Yey-associated cognitive phenotypes were not rescued by either deletion in the compound mutants, suggesting the possible presence of at least one causative gene in each of the two regions. The partial rescue by a Dyrk1a mutation in a compound mutant carrying Dp(16)1Yey and the Dyrk1a mutation confirmed the causative role of Dyrk1a, whereas the absence of a similar rescue by Df(16Dyrk1a-Kcnj6)Yey in Dp(16)1Yey/Df(16Dyrk1a-Kcnj6)Yey mice demonstrated the importance of Kcnj6. Our results revealed the high levels of complexities of gene actions and interactions associated with the Setd4/Cbr1-Fam3b/Mx2 region as well as their relationship with developmental cognitive deficits in DS.
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Affiliation(s)
- Xiaoling Jiang
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Chunhong Liu
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Tao Yu
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA, Department of Medical Genetics, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Li Zhang
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA, Department of Physiology and Pathophysiology, Medical School of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Kai Meng
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA, Department of Physiology and Pathophysiology, Medical School of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Zhuo Xing
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Pavel V Belichenko
- Department of Neurosciences, School of Medicine, University of California at San Diego, La Jolla, CA 92093, USA and
| | - Alexander M Kleschevnikov
- Department of Neurosciences, School of Medicine, University of California at San Diego, La Jolla, CA 92093, USA and
| | - Annie Pao
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Jennifer Peresie
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Sarah Wie
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - William C Mobley
- Department of Neurosciences, School of Medicine, University of California at San Diego, La Jolla, CA 92093, USA and
| | - Y Eugene Yu
- The Children's Guild Foundation Down Syndrome Research Program, Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA, Genetics, Genomics and Bioinformatics Program, Department of Cellular and Molecular Biology, Roswell Park Division of Graduate School,State University of New York at Buffalo, Buffalo, NY 14263, USA
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Begenisic T, Sansevero G, Baroncelli L, Cioni G, Sale A. Early environmental therapy rescues brain development in a mouse model of Down syndrome. Neurobiol Dis 2015; 82:409-419. [PMID: 26244989 DOI: 10.1016/j.nbd.2015.07.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 06/26/2015] [Accepted: 07/31/2015] [Indexed: 01/15/2023] Open
Abstract
Down syndrome (DS), the most common genetic disorder associated with intellectual disabilities, is an untreatable condition characterized by a number of developmental defects and permanent deficits in the adulthood. Ts65Dn mice, the major animal model for DS, display severe cognitive and synaptic plasticity defects closely resembling the human phenotype. Here, we employed a multidisciplinary approach to investigate, for the first time in developing Ts65Dn mice, the effects elicited by early environmental enrichment (EE) on brain maturation and function. We report that exposure to EE resulted in a robust increase in maternal care levels displayed by Ts65Dn mothers and led to a normalization of declarative memory abilities and hippocampal plasticity in trisomic offspring. The positive effects of EE on Ts65Dn phenotype were not limited to the cognitive domain, but also included a rescue of visual system maturation. The beneficial EE effects were accompanied by increased BDNF and correction of over-expression of the GABA vesicular transporter vGAT. These findings highlight the beneficial impact of early environmental stimuli and their potential for application in the treatment of major functional deficits in children with DS.
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Affiliation(s)
| | | | | | - Giovanni Cioni
- Department of Developmental Neuroscience, IRCCS Stella Maris, University of Pisa, Calambrone, I-56100 Pisa, Italy
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Ahmed MM, Dhanasekaran AR, Block A, Tong S, Costa ACS, Stasko M, Gardiner KJ. Protein dynamics associated with failed and rescued learning in the Ts65Dn mouse model of Down syndrome. PLoS One 2015; 10:e0119491. [PMID: 25793384 PMCID: PMC4368539 DOI: 10.1371/journal.pone.0119491] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 01/14/2015] [Indexed: 02/08/2023] Open
Abstract
Down syndrome (DS) is caused by an extra copy of human chromosome 21 (Hsa21). Although it is the most common genetic cause of intellectual disability (ID), there are, as yet, no effective pharmacotherapies. The Ts65Dn mouse model of DS is trisomic for orthologs of ∼55% of Hsa21 classical protein coding genes. These mice display many features relevant to those seen in DS, including deficits in learning and memory (L/M) tasks requiring a functional hippocampus. Recently, the N-methyl-D-aspartate (NMDA) receptor antagonist, memantine, was shown to rescue performance of the Ts65Dn in several L/M tasks. These studies, however, have not been accompanied by molecular analyses. In previous work, we described changes in protein expression induced in hippocampus and cortex in control mice after exposure to context fear conditioning (CFC), with and without memantine treatment. Here, we extend this analysis to Ts65Dn mice, measuring levels of 85 proteins/protein modifications, including components of MAP kinase and MTOR pathways, and subunits of NMDA receptors, in cortex and hippocampus of Ts65Dn mice after failed learning in CFC and after learning was rescued by memantine. We show that, compared with wild type littermate controls, (i) of the dynamic responses seen in control mice in normal learning, >40% also occur in Ts65Dn in failed learning or are compensated by baseline abnormalities, and thus are considered necessary but not sufficient for successful learning, and (ii) treatment with memantine does not in general normalize the initial protein levels but instead induces direct and indirect responses in approximately half the proteins measured and results in normalization of the endpoint protein levels. Together, these datasets provide a first view of the complexities associated with pharmacological rescue of learning in the Ts65Dn. Extending such studies to additional drugs and mouse models of DS will aid in identifying pharmacotherapies for effective clinical trials.
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Affiliation(s)
- Md. Mahiuddin Ahmed
- Linda Crnic Institute for Down Syndrome, Department of Pediatrics, University of Colorado Denver, Mail Stop 8608, 12700 E 19th Avenue, Aurora, Colorado 80045, United States of America
| | - A. Ranjitha Dhanasekaran
- Linda Crnic Institute for Down Syndrome, Department of Pediatrics, University of Colorado Denver, Mail Stop 8608, 12700 E 19th Avenue, Aurora, Colorado 80045, United States of America
| | - Aaron Block
- Linda Crnic Institute for Down Syndrome, Department of Pediatrics, University of Colorado Denver, Mail Stop 8608, 12700 E 19th Avenue, Aurora, Colorado 80045, United States of America
| | - Suhong Tong
- Colorado School of Public Health, University of Colorado Denver, Mail Stop A036-B065 TCH, 12700 E 19th Avenue, Aurora, Colorado 80045, United States of America
| | - Alberto C. S. Costa
- Division of Pediatric Neurology, Mail Stop RBC 6090, Department of Pediatrics, Case Western Reserve School of Medicine, Rainbow Babies & Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106–6090, United States of America
| | - Melissa Stasko
- Division of Pediatric Neurology, Mail Stop RBC 6090, Department of Pediatrics, Case Western Reserve School of Medicine, Rainbow Babies & Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106–6090, United States of America
| | - Katheleen J. Gardiner
- Linda Crnic Institute for Down Syndrome, Department of Pediatrics, University of Colorado Denver, Mail Stop 8608, 12700 E 19th Avenue, Aurora, Colorado 80045, United States of America
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Mail Stop 8608, 12700 E 19th Avenue, Aurora, Colorado 80045, United States of America
- Human Medical Genetics and Genomics, and Neuroscience Programs, University of Colorado Denver, Mail Stop 8608, 12700 E 19th Avenue, Aurora, Colorado 80045, United States of America
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Brault V, Duchon A, Romestaing C, Sahun I, Pothion S, Karout M, Borel C, Dembele D, Bizot JC, Messaddeq N, Sharp AJ, Roussel D, Antonarakis SE, Dierssen M, Hérault Y. Opposite phenotypes of muscle strength and locomotor function in mouse models of partial trisomy and monosomy 21 for the proximal Hspa13-App region. PLoS Genet 2015; 11:e1005062. [PMID: 25803843 PMCID: PMC4372517 DOI: 10.1371/journal.pgen.1005062] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Accepted: 02/09/2015] [Indexed: 12/22/2022] Open
Abstract
The trisomy of human chromosome 21 (Hsa21), which causes Down syndrome (DS), is the most common viable human aneuploidy. In contrast to trisomy, the complete monosomy (M21) of Hsa21 is lethal, and only partial monosomy or mosaic monosomy of Hsa21 is seen. Both conditions lead to variable physiological abnormalities with constant intellectual disability, locomotor deficits, and altered muscle tone. To search for dosage-sensitive genes involved in DS and M21 phenotypes, we created two new mouse models: the Ts3Yah carrying a tandem duplication and the Ms3Yah carrying a deletion of the Hspa13-App interval syntenic with 21q11.2-q21.3. Here we report that the trisomy and the monosomy of this region alter locomotion, muscle strength, mass, and energetic balance. The expression profiling of skeletal muscles revealed global changes in the regulation of genes implicated in energetic metabolism, mitochondrial activity, and biogenesis. These genes are downregulated in Ts3Yah mice and upregulated in Ms3Yah mice. The shift in skeletal muscle metabolism correlates with a change in mitochondrial proliferation without an alteration in the respiratory function. However, the reactive oxygen species (ROS) production from mitochondrial complex I decreased in Ms3Yah mice, while the membrane permeability of Ts3Yah mitochondria slightly increased. Thus, we demonstrated how the Hspa13-App interval controls metabolic and mitochondrial phenotypes in muscles certainly as a consequence of change in dose of Gabpa, Nrip1, and Atp5j. Our results indicate that the copy number variation in the Hspa13-App region has a peripheral impact on locomotor activity by altering muscle function.
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Affiliation(s)
- Véronique Brault
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Arnaud Duchon
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | | | - Ignasi Sahun
- Genes and Disease Program, Center for Genomic Regulation, Barcelona, Spain, and CIBER de Enfermedades Raras (CIBERER), Barcelona, Spain
| | - Stéphanie Pothion
- Transgenese et Archivage Animaux Modèles, TAAM, CNRS, UPS44, Orléans, France
| | - Mona Karout
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Christelle Borel
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | - Doulaye Dembele
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | | | - Nadia Messaddeq
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Andrew J. Sharp
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Damien Roussel
- LEHNA, CNRS UMR502, Université de Lyon, Villeurbanne, France
| | - Stylianos E Antonarakis
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
- iGE3 Institute of Genetics and Genomics of Geneva, Geneva, Switzerland
| | - Mara Dierssen
- Genes and Disease Program, Center for Genomic Regulation, Barcelona, Spain, and CIBER de Enfermedades Raras (CIBERER), Barcelona, Spain
| | - Yann Hérault
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France
- Université de Strasbourg, Illkirch, France
- Institut Clinique de la Souris, PHENOMIN, GIE CERBM, Illkirch, France
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Dutka T, Hallberg D, Reeves RH. Chronic up-regulation of the SHH pathway normalizes some developmental effects of trisomy in Ts65Dn mice. Mech Dev 2015; 135:68-80. [PMID: 25511459 PMCID: PMC4297701 DOI: 10.1016/j.mod.2014.11.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 11/24/2014] [Accepted: 11/25/2014] [Indexed: 01/23/2023]
Abstract
Down Syndrome (DS) is a highly complex developmental genetic disorder caused by trisomy for human chromosome 21 (Hsa21). All individuals with DS exhibit some degree of brain structural changes and cognitive impairment; mouse models such as Ts65Dn have been instrumental in understanding the underlying mechanisms. Several phenotypes of DS might arise from a reduced response of trisomic cells to the Sonic Hedgehog (SHH) growth factor. If all trisomic cells show a similar reduced response to SHH, then up-regulation of the pathway in trisomic cells might ameliorate multiple DS phenotypes. We crossed Ptch1tm1Mps/+ mice, in which the canonical SHH pathway is expected to be up-regulated in every SHH-responsive cell due to the loss of function of one allele of the pathway suppressor, Ptch1, to the Ts65Dn DS model and assessed the progeny for possible rescue of multiple DS-related phenotypes. Down-regulation of Ptch produced several previously unreported effects on development by itself, complicating interpretation of some phenotypes, and a number of structural or behavioral effects of trisomy were not compensated by SHH signaling. However, a deficit in a nest-building task was partially restored in Ts;Ptch+/- mice, as were the structural anomalies of the cerebellum seen in Ts65Dn mice. These results extend the body of evidence indicating that reduced response to SHH in trisomic cells and tissues contributes to various aspects of the trisomic phenotype.
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Affiliation(s)
- Tara Dutka
- Department of Physiology and Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Dorothy Hallberg
- Department of Physiology and Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Roger H Reeves
- Department of Physiology and Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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38
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Hanson MG, Wilde JJ, Moreno RL, Minic AD, Niswander L. Potassium dependent rescue of a myopathy with core-like structures in mouse. eLife 2015; 4. [PMID: 25564733 PMCID: PMC4309926 DOI: 10.7554/elife.02923] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 01/07/2015] [Indexed: 01/24/2023] Open
Abstract
Myopathies decrease muscle functionality. Mutations in ryanodine receptor 1 (RyR1) are often associated with myopathies with microscopic core-like structures in the muscle fiber. In this study, we identify a mouse RyR1 model in which heterozygous animals display clinical and pathological hallmarks of myopathy with core-like structures. The RyR1 mutation decreases sensitivity to activated calcium release and myoplasmic calcium levels, subsequently affecting mitochondrial calcium and ATP production. Mutant muscle shows a persistent potassium leak and disrupted expression of regulators of potassium homeostasis. Inhibition of KATP channels or increasing interstitial potassium by diet or FDA-approved drugs can reverse the muscle weakness, fatigue-like physiology and pathology. We identify regulators of potassium homeostasis as biomarkers of disease that may reveal therapeutic targets in human patients with myopathy of central core disease (CCD). Altogether, our results suggest that amelioration of potassium leaks through potassium homeostasis mechanisms may minimize muscle damage of myopathies due to certain RyR1 mutations.
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Affiliation(s)
- M Gartz Hanson
- Department of Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Jonathan J Wilde
- Department of Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Rosa L Moreno
- Department of Physiology, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Angela D Minic
- Department of Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Lee Niswander
- Department of Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, United States
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39
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Developmental localization of adhesion and scaffolding proteins at the cone synapse. Gene Expr Patterns 2014; 16:36-50. [PMID: 25176525 DOI: 10.1016/j.gep.2014.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 06/30/2014] [Accepted: 07/07/2014] [Indexed: 11/22/2022]
Abstract
The cone synapse is a complex signaling hub composed of the cone photoreceptor terminal and the dendrites of bipolar and horizontal cells converging around multiple ribbon synapses. Factors that promote organization of this structure are largely unexplored. In this study we characterize the localization of adhesion and scaffolding proteins that are localized to the cone synapse, including alpha-n-catenin, beta-catenin, gamma-protocadherin, cadherin-8, MAGI2 and CASK. We describe the localization of these proteins during development of the mouse retina and in the adult macaque retina and find that these proteins are concentrated at the cone synapse. The localization of these proteins was then characterized at the cellular and subcellular levels. Alpha-n-catenin, gamma-protocadherin and cadherin-8 were concentrated in the dendrites of bipolar cells that project to the cone synapse but were not detected or stained very dimly in the dendrites of cells projecting to rod synapses. This study adds to our knowledge of cone synapse development by characterizing the developmental localization of these factors and identifies these factors as candidates for functional analysis of cone synapse formation.
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40
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Zampieri BL, Fernandez F, Pearson JN, Stasko MR, Costa ACS. Ultrasonic vocalizations during male-female interaction in the mouse model of Down syndrome Ts65Dn. Physiol Behav 2014; 128:119-25. [PMID: 24534182 DOI: 10.1016/j.physbeh.2014.02.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 02/06/2014] [Indexed: 11/25/2022]
Abstract
Down syndrome (DS) is the leading cause of genetically defined intellectual disability. Although speech and language impairments are salient features of this disorder, the nature of these phenotypes and the degree to which they are exacerbated by concomitant oromotor dysfunction and/or hearing deficit are poorly understood. Mouse models like Ts65Dn, the most extensively used DS animal model, have been critical to understanding the genetic and developmental mechanisms that contribute to intellectual disability. In the present study, we characterized the properties of the ultrasonic vocalizations (USVs) emitted by Ts65Dn males during courtship episodes with female partners. USVs emitted by mice in this setting have been proposed to have some basic correlation to human speech. Data were collected and analyzed from 22 Ts65Dn mice and 22 of their euploid littermates. We found that both the minimum and maximum peak frequencies of Ts65Dn calls were lower than those produced by euploid mice, whereas the mean individual duration of "down" and "complex" syllable types was significantly longer. Peak, minimal and maximal, and the fundamental frequencies of short syllables generated by Ts65Dn mice were lower compared to those by euploid mice. Finally, Ts65Dn males made fewer multiple jumps calls during courtship and the mean total duration of their "arc", "u", and "complex" syllables was longer. We discuss the human correlates to these findings, their translational potential, and the limitations of this approach. To our knowledge, this is the first characterization of differences between adult Ts65Dn and euploid control mice with respect to USVs.
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Affiliation(s)
- Bruna L Zampieri
- Unidade de Pesquisa em Biologia Molecular e Genética, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, São Paulo, Brazil; Division of Pediatric Neurology, Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Fabian Fernandez
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jennifer N Pearson
- Neuroscience Program, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States
| | - Melissa R Stasko
- Division of Pediatric Neurology, Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Alberto C S Costa
- Division of Pediatric Neurology, Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States.
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Size does not always matter: Ts65Dn Down syndrome mice show cerebellum-dependent motor learning deficits that cannot be rescued by postnatal SAG treatment. J Neurosci 2013; 33:15408-13. [PMID: 24068809 DOI: 10.1523/jneurosci.2198-13.2013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Humans with Down syndrome (DS) and Ts65Dn mice both show a reduced volume of the cerebellum due to a significant reduction in the density of granule neurons. Recently, cerebellar hypoplasia in Ts65Dn mice was rescued by a single treatment with SAG, an agonist of the Sonic hedgehog pathway, administered on the day of birth. In addition to normalizing cerebellar morphology, this treatment restored the ability to learn a spatial navigation task, which is associated with hippocampal function. It is not clear to what extent this improved performance results from restoration of the cerebellar architecture or a yet undefined role of Sonic hedgehog (Shh) in perinatal hippocampal development. The absence of a clearly demonstrated deficit in cerebellar function in trisomic mice exacerbates the problem of discerning how SAG acts to improve learning and memory. Here we show that phase reversal adaptation and consolidation of the vestibulo-ocular reflex is significantly impaired in Ts65Dn mice, providing for the first time a precise characterization of cerebellar functional deficits in this murine model of DS. However, these deficits do not benefit from the normalization of cerebellar morphology following treatment with SAG. Together with the previous observation that the synaptic properties of Purkinje cells are also unchanged by SAG treatment, this lack of improvement in a region-specific behavioral assay supports the possibility that a direct effect of Shh pathway stimulation on the hippocampus might explain the benefits of this potential approach to the improvement of cognition in DS.
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42
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Begenisic T, Baroncelli L, Sansevero G, Milanese M, Bonifacino T, Bonanno G, Cioni G, Maffei L, Sale A. Fluoxetine in adulthood normalizes GABA release and rescues hippocampal synaptic plasticity and spatial memory in a mouse model of Down syndrome. Neurobiol Dis 2013; 63:12-9. [PMID: 24269730 DOI: 10.1016/j.nbd.2013.11.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 10/18/2013] [Accepted: 11/12/2013] [Indexed: 11/17/2022] Open
Abstract
Down syndrome (DS) is the most common genetic disorder associated with mental retardation. It has been repeatedly shown that Ts65Dn mice, the major animal model for DS, have severe cognitive and synaptic plasticity dysfunctions caused by excessive inhibition in their temporal lobe structures. Here we employed a multidisciplinary approach spanning from the behavioral to the electrophysiological and molecular level to investigate the effects elicited by fluoxetine on cognitive abilities, hippocampal synaptic plasticity and GABA release in adult Ts65Dn mice. We report that a chronic treatment with fluoxetine administered in the drinking water normalizes GABA release and promotes recovery of spatial memory abilities, spatial working memory for alternation, and hippocampal synaptic plasticity in adult Ts65Dn mice. Our findings might encourage new experimental attempts aimed at investigating the potential of fluoxetine for application in the treatment of major functional deficits in adult people with DS.
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Affiliation(s)
| | | | | | - Marco Milanese
- Department of Pharmacy, Section of Pharmacology and Toxicology Unit, University of Genova, Genova I-16148, Italy
| | - Tiziana Bonifacino
- Department of Pharmacy, Section of Pharmacology and Toxicology Unit, University of Genova, Genova I-16148, Italy
| | - Giambattista Bonanno
- Department of Pharmacy, Section of Pharmacology and Toxicology Unit, University of Genova, Genova I-16148, Italy
| | - Giovanni Cioni
- Department of Developmental Neuroscience, IRCCS Stella Maris and University of Pisa, Calambrone, Pisa I-56100, Italy
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Cisterna B, Costanzo M, Scherini E, Zancanaro C, Malatesta M. Ultrastructural features of skeletal muscle in adult and aging Ts65Dn mice, a murine model of Down syndrome. Muscles Ligaments Tendons J 2013; 3:287-294. [PMID: 24596692 PMCID: PMC3940502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Patients with Down syndrome (DS) suffer from muscle hypotonia and an altered motor coordination whose basic mechanisms are still largely unknown. Interestingly, they show muscle weakness like healthy aged subjects, suggesting possible similarity with sarcopenia: to test this hypothesis, the Ts65Dn mouse, a suitable animal model of DS, was employed. The fine structure of skeletal fibres of the quadriceps femoris muscle was analysed in adult (12 months) and aging (19 months) animals and their age-matched euploid controls by combining morphometry and immunocytochemistry at transmission electron microscopy. Results demonstrated structural alterations of mitochondria and myonuclei reminiscent of those observed in age-related sarcopenia, supporting the hypothesis that trisomy leads to an early aging of skeletal muscle consistent with the multi-systemic premature aging typical of DS.
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Affiliation(s)
- Barbara Cisterna
- Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Italy
| | - Manuela Costanzo
- Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Italy
| | - Elda Scherini
- Department of Biology and Biotechnology, Laboratory of Cell Biology and Neurology, University of Pavia, Italy
| | - Carlo Zancanaro
- Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Italy
| | - Manuela Malatesta
- Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Italy
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Abstract
Down syndrome (DS), which results from an extra copy of chromosome 21 (trisomy 21), is the most common genetically defined cause of intellectual disability. Although no pharmacotherapy aimed at counteracting the cognitive and adaptive deficits associated with this genetic disorder has been approved at present, there have been several new promising studies on pharmacological agents capable of rescuing learning/memory deficits seen in mouse models of DS. Here, we will review the available mouse models for DS and provide a comprehensive, albeit not exhaustive review of the following preclinical research strategies: (1) SOD1 and antioxidant agents; (2) APP and γ-secretase inhibitors; (3) DYRK1A and the polyphenol epigallocatechin gallate (EGCG); (4) GIRK2 and fluoxetine; (5) adrenergic receptor agonists; (6) modulation of GABAA and GABAB receptors; (7) agonism of the hedgehog signaling pathway; (8) nerve growth factor (NGF) and other neurotrophic factors; (9) anticholinesterase (AChE) agents; and (10) antagonism of NMDA receptors. Finally, we will review briefly five different strategies in DS that have led to clinical studies that either have been concluded or are currently underway: (1) antioxidant therapy; (2) AChE therapy; (3) green tea extract therapy; (4) RG1662 therapy; and (5) memantine therapy. These are exciting times in DS research. Within a decade or so, it is well into the realm of possibility that new forms of pharmacotherapies might become valuable tools in the armamentarium of developmental clinicians, as adjutants to more traditional and proven forms of habilitative interventions aimed at improving the quality of life of individuals with DS.
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45
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Hanson JE, Weber M, Meilandt WJ, Wu T, Luu T, Deng L, Shamloo M, Sheng M, Scearce-Levie K, Zhou Q. GluN2B antagonism affects interneurons and leads to immediate and persistent changes in synaptic plasticity, oscillations, and behavior. Neuropsychopharmacology 2013; 38:1221-33. [PMID: 23340518 PMCID: PMC3656364 DOI: 10.1038/npp.2013.19] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Although antagonists to GluN2B-containing N-methyl-D-aspartate receptors (NMDARs) have been widely considered to be neuroprotective under certain pathological conditions, their immediate and lasting impacts on synaptic, circuit, and cognitive functions are poorly understood. In hippocampal slices, we found that the GluN2B-selective antagonist Ro25-6981 (Ro25) reduced synaptic NMDAR responses and consequently neuronal output in a subpopulation of GABAergic interneurons, but not pyramidal neurons. Consistent with these effects, Ro25 reduced GABAergic responses in pyramidal neurons and hence could affect circuit functions by altering the excitation/inhibition balance in the brain. In slices from Ts65Dn mice, a Down syndrome model with excess inhibition and cognitive impairment, acutely applied Ro25-rescued long-term potentiation (LTP) and gamma oscillation deficits, whereas prolonged dosing induced persistent rescue of LTP. In contrast, Ro25 did not impact LTP in wild-type (wt) mice but reduced gamma oscillations both acutely and following prolonged treatment. Although acute Ro25 treatment impaired memory performance in wt mice, memory deficits in Ts65Dn mice were unchanged. Thus, GluN2B-NMDARs contribute to the excitation/inhibition balance via impacts on interneurons, and blocking GluN2B-NMDARs can alter functions that depend on this balance, including synaptic plasticity, gamma oscillations, and memory. That prolonged GluN2B antagonism leads to persistent changes in synaptic and circuit functions, and that the influence of GluN2B antagonism differs between wt and disease model mice, provide critical insight into the therapeutic potential and possible liabilities of GluN2B antagonists.
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Affiliation(s)
- Jesse E Hanson
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA
| | - Martin Weber
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA
| | - William J Meilandt
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA
| | - Tiffany Wu
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA
| | - Tom Luu
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA
| | - Lunbin Deng
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA
| | - Mehrdad Shamloo
- Stanford Behavioral and Functional Neuroscience Laboratory, Stanford, CA, USA
| | - Morgan Sheng
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA
| | | | - Qiang Zhou
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA, USA,Department of Neuroscience, Genentech, Inc., 1 DNA Way, MS 230B, South San Francisco, CA 94080, USA, Tel: +1 650 467 7750, Fax: +1 650 225 4000, E-mail:
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46
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Cowley PM, Keslacy S, Middleton FA, DeRuisseau LR, Fernhall B, Kanaley JA, DeRuisseau KC. Functional and biochemical characterization of soleus muscle in Down syndrome mice: insight into the muscle dysfunction seen in the human condition. Am J Physiol Regul Integr Comp Physiol 2012; 303:R1251-60. [DOI: 10.1152/ajpregu.00312.2012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Persons with Down syndrome (DS) exhibit low muscle strength that significantly impairs their physical functioning. The Ts65Dn mouse model of DS also exhibits muscle weakness in vivo and may be a useful model to examine DS-associated muscle dysfunction. Therefore, the purpose of this experiment was to directly assess skeletal muscle function in the Ts65Dn mouse and to reveal potential mechanisms of DS-associated muscle weakness. Soleus muscles were harvested from anesthetized male Ts65Dn and wild-type (WT) colony controls. In vitro muscle contractile experiments revealed normal force generation of nonfatigued Ts65Dn soleus, but a 12% reduction in force was observed during recovery from fatiguing contractions compared with WT muscle ( P < 0.05). Indicators of oxidative stress and mitochondrial oxidative capacity were assessed to reveal potential mechanisms of DS-associated muscle weakness. Protein expression of copper-zinc superoxide dismutase (SOD1), a triplicated gene in persons with DS and Ts65Dn mice, was increased 25% ( P < 0.05) in Ts65Dn soleus. Nontriplicated antioxidant protein expression was similar between groups. Lipid peroxidation was unaltered in Ts65Dn animals, but protein oxidation was 20% greater compared with controls ( P < 0.05). Cytochrome- c oxidase expression was 22% lower in Ts65Dn muscle ( P < 0.05), while expression of citrate synthase was similar between groups. Microarray analysis revealed alteration of numerous pathways in Ts65Dn muscle, including proteolysis, glucose and fat metabolism, neuromuscular transmission, and ATP biosynthesis. In summary, despite biochemical and gene expression differences in soleus muscle of Ts65Dn animals, the functional properties of skeletal muscle likely contribute a minor part to the in vivo muscle weakness.
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Affiliation(s)
- Patrick M. Cowley
- Syracuse University, Department of Exercise Science, Syracuse, New York
| | - Stefan Keslacy
- Syracuse University, Department of Exercise Science, Syracuse, New York
| | - Frank A. Middleton
- State University of New York Upstate Medical University, Department of Neuroscience and Physiology, Syracuse, New York
| | | | - Bo Fernhall
- University of Illinois at Chicago, College of Applied Health Sciences, Chicago, Illinois; and
| | - Jill A. Kanaley
- University of Missouri, Department of Nutrition and Exercise Physiology, Columbia, Missouri
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47
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The use of mouse models for understanding the biology of down syndrome and aging. Curr Gerontol Geriatr Res 2012; 2012:717315. [PMID: 22461792 PMCID: PMC3296169 DOI: 10.1155/2012/717315] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Accepted: 12/06/2011] [Indexed: 12/16/2022] Open
Abstract
Down syndrome is a complex condition caused by trisomy of human chromosome 21. The biology of aging may be different in individuals with Down syndrome; this is not well understood in any organism. Because of its complexity, many aspects of Down syndrome must be studied either in humans or in animal models. Studies in humans are essential but are limited for ethical and practical reasons. Fortunately, genetically altered mice can serve as extremely useful models of Down syndrome, and progress in their production and analysis has been remarkable. Here, we describe various mouse models that have been used to study Down syndrome. We focus on segmental trisomies of mouse chromosome regions syntenic to human chromosome 21, mice in which individual genes have been introduced, or mice in which genes have been silenced by targeted mutagenesis. We selected a limited number of genes for which considerable evidence links them to aspects of Down syndrome, and about which much is known regarding their function. We focused on genes important for brain and cognitive function, and for the altered cancer spectrum seen in individuals with Down syndrome. We conclude with observations on the usefulness of mouse models and speculation on future directions.
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48
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Heterogeneous reallocation of presynaptic efficacy in recurrent excitatory circuits adapting to inactivity. Nat Neurosci 2011; 15:250-7. [PMID: 22179109 PMCID: PMC3558750 DOI: 10.1038/nn.3004] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 11/04/2011] [Indexed: 02/08/2023]
Abstract
Recurrent excitatory circuits face extreme challenges in balancing efficacy and stability. We recorded from CA3 pyramidal neuron pairs in rat hippocampal slice cultures to characterize synaptic and circuit-level changes in recurrent synapses resulting from long-term inactivity. Chronic tetrodotoxin treatment greatly reduced the percentage of connected CA3-CA3 neurons, but enhanced the strength of the remaining connections; presynaptic release probability sharply increased, whereas quantal size was unaltered. Connectivity was decreased in activity-deprived circuits by functional silencing of synapses, whereas three-dimensional anatomical analysis revealed no change in spine or bouton density or aggregate dendrite length. The silencing arose from enhanced Cdk5 activity and could be reverted by acute Cdk5 inhibition with roscovitine. Our results suggest that recurrent circuits adapt to chronic inactivity by reallocating presynaptic weights heterogeneously, strengthening certain connections while silencing others. This restricts synaptic output and input, preserving signaling efficacy among a subset of neuronal ensembles while protecting network stability.
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Scott-McKean JJ, Costa ACS. Exaggerated NMDA mediated LTD in a mouse model of Down syndrome and pharmacological rescuing by memantine. Learn Mem 2011; 18:774-8. [PMID: 22101180 DOI: 10.1101/lm.024182.111] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The Ts65Dn mouse is the best-studied animal model for Down syndrome. In the experiments described here, NMDA-mediated or mGluR-mediated LTD was induced in the CA1 region of hippocampal slices from Ts65Dn and euploid control mice by bath application of 20 µM NMDA for 3 min and 50 µM DHPG for 5 min, respectively. We found that Ts65Dn mice display exaggerated NMDA-induced, but not mGluR-induced, LTD in the CA1 region of the hippocampus compared with euploid control animals. In addition, this abnormal level of LTD can be pharmacologically rescued by the NMDA receptor antagonist memantine.
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Affiliation(s)
- Jonah J Scott-McKean
- Neuroscience Training Program, University of Colorado, Anschutz Medical Campus, Aurora, Colorado 80045, USA
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50
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Simoes de Souza FM, Busquet N, Blatner M, Maclean KN, Restrepo D. Galantamine improves olfactory learning in the Ts65Dn mouse model of Down syndrome. Sci Rep 2011; 1:137. [PMID: 22355654 PMCID: PMC3216618 DOI: 10.1038/srep00137] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 09/28/2011] [Indexed: 11/20/2022] Open
Abstract
Down syndrome (DS) is the most common form of congenital intellectual disability. Although DS involves multiple disturbances in various tissues, there is little doubt that in terms of quality of life cognitive impairment is the most serious facet and there is no effective treatment for this aspect of the syndrome. The Ts65Dn mouse model of DS recapitulates multiple aspects of DS including cognitive impairment. Here the Ts65Dn mouse model of DS was evaluated in an associative learning paradigm based on olfactory cues. In contrast to disomic controls, trisomic mice exhibited significant deficits in olfactory learning. Treatment of trisomic mice with the acetylcholinesterase inhibitor galantamine resulted in a significant improvement in olfactory learning. Collectively, our study indicates that olfactory learning can be a sensitive tool for evaluating deficits in associative learning in mouse models of DS and that galantamine has therapeutic potential for improving cognitive abilities.
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Affiliation(s)
- Fabio M. Simoes de Souza
- Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A.
- These authors contributed equally to this work
| | - Nicolas Busquet
- Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A.
- Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A
- These authors contributed equally to this work
| | | | - Kenneth N. Maclean
- Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A
| | - Diego Restrepo
- Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A.
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