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Thompson SM. Modulators of GABA A receptor-mediated inhibition in the treatment of neuropsychiatric disorders: past, present, and future. Neuropsychopharmacology 2024; 49:83-95. [PMID: 37709943 PMCID: PMC10700661 DOI: 10.1038/s41386-023-01728-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 07/14/2023] [Accepted: 08/08/2023] [Indexed: 09/16/2023]
Abstract
The predominant inhibitory neurotransmitter in the brain, γ-aminobutyric acid (GABA), acts at ionotropic GABAA receptors to counterbalance excitation and regulate neuronal firing. GABAA receptors are heteropentameric channels comprised from subunits derived from 19 different genes. GABAA receptors have one of the richest and well-developed pharmacologies of any therapeutic drug target, including agonists, antagonists, and positive and negative allosteric modulators (PAMs, NAMs). Currently used PAMs include benzodiazepine sedatives and anxiolytics, barbiturates, endogenous and synthetic neurosteroids, and general anesthetics. In this article, I will review evidence that these drugs act at several distinct binding sites and how they can be used to alter the balance between excitation and inhibition. I will also summarize existing literature regarding (1) evidence that changes in GABAergic inhibition play a causative role in major depression, anxiety, postpartum depression, premenstrual dysphoric disorder, and schizophrenia and (2) whether and how GABAergic drugs exert beneficial effects in these conditions, focusing on human studies where possible. Where these classical therapeutics have failed to exert benefits, I will describe recent advances in clinical and preclinical drug development. I will also highlight opportunities to advance a generation of GABAergic therapeutics, such as development of subunit-selective PAMs and NAMs, that are engendering hope for novel tools to treat these devastating conditions.
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Affiliation(s)
- Scott M Thompson
- Center for Novel Therapeutics, Department of Psychiatry, University of Colorado School of Medicine, 12700 E. 19th Ave., Aurora, CO, 80045, USA.
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2
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Lam P, Newland J, Faull RLM, Kwakowsky A. Cation-Chloride Cotransporters KCC2 and NKCC1 as Therapeutic Targets in Neurological and Neuropsychiatric Disorders. Molecules 2023; 28:1344. [PMID: 36771011 PMCID: PMC9920462 DOI: 10.3390/molecules28031344] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/21/2023] [Accepted: 01/25/2023] [Indexed: 02/04/2023] Open
Abstract
Neurological diseases including Alzheimer's, Huntington's disease, Parkinson's disease, Down syndrome and epilepsy, and neuropsychiatric disorders such as schizophrenia, are conditions that affect not only individuals but societies on a global scale. Current therapies offer a means for small symptomatic relief, but recently there has been increasing demand for therapeutic alternatives. The γ-aminobutyric acid (GABA)ergic signaling system has been investigated for developing new therapies as it has been noted that any dysfunction or changes to this system can contribute to disease progression. Expression of the K-Cl-2 (KCC2) and N-K-C1-1 (NKCC1) cation-chloride cotransporters (CCCs) has recently been linked to the disruption of GABAergic activity by affecting the polarity of GABAA receptor signaling. KCC2 and NKCC1 play a part in multiple neurological and neuropsychiatric disorders, making them a target of interest for potential therapies. This review explores current research suggesting the pathophysiological role and therapeutic importance of KCC2 and NKCC1 in neuropsychiatric and neurological disorders.
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Affiliation(s)
- Patricia Lam
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1023, New Zealand
| | - Julia Newland
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1023, New Zealand
| | - Richard L. M. Faull
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1023, New Zealand
| | - Andrea Kwakowsky
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1023, New Zealand
- Pharmacology and Therapeutics, School of Medicine, Galway Neuroscience Centre, University of Galway, H91 W5P7 Galway, Ireland
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3
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Bhattacharya D, Bartley AF, Li Q, Dobrunz LE. Bicuculline restores frequency-dependent hippocampal I/E ratio and circuit function in PGC-1ɑ null mice. Neurosci Res 2022; 184:9-18. [PMID: 35842011 PMCID: PMC10865982 DOI: 10.1016/j.neures.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 06/22/2022] [Accepted: 07/12/2022] [Indexed: 10/31/2022]
Abstract
Altered inhibition/excitation (I/E) balance contributes to various brain disorders. Dysfunctional GABAergic interneurons enhance or reduce inhibition, resulting in I/E imbalances. Differences in short-term plasticity between excitation and inhibition cause frequency-dependence of the I/E ratio, which can be altered by GABAergic dysfunction. However, it is unknown whether I/E imbalances can be rescued pharmacologically using a single dose when the imbalance magnitude is frequency-dependent. Loss of PGC-1α (peroxisome proliferator activated receptor γ coactivator 1α) causes transcriptional dysregulation in hippocampal GABAergic interneurons. PGC-1α-/- slices have enhanced baseline inhibition onto CA1 pyramidal cells, causing increased I/E ratio and impaired circuit function. High frequency stimulation reduces the I/E ratio and recovers circuit function in PGC-1α-/- slices. Here we tested if using a low dose of bicuculline that can restore baseline I/E ratio can also rescue the frequency-dependent I/E imbalances in these mice. Remarkably, bicuculline did not reduce the I/E ratio below that of wild type during high frequency stimulation. Interestingly, bicuculline enhanced the paired-pulse ratio (PPR) of disynaptic inhibition without changing the monosynaptic inhibition PPR, suggesting that bicuculline modifies interneuron recruitment and not GABA release. Bicuculline improved CA1 output in PGC-1α-/- slices, enhancing EPSP-spike coupling to wild type levels at high and low frequencies. Our results show that it is possible to rescue frequency-dependent I/E imbalances in an animal model of transcriptional dysregulation with a single treatment.
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Affiliation(s)
- Dwipayan Bhattacharya
- Department of Neurobiology, Civitan International Research Center, and Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, United States
| | - Aundrea F Bartley
- Department of Neurobiology, Civitan International Research Center, and Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, United States
| | - Qin Li
- Department of Neurobiology, Civitan International Research Center, and Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, United States
| | - Lynn E Dobrunz
- Department of Neurobiology, Civitan International Research Center, and Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, United States.
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4
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Bartesaghi R. Brain circuit pathology in Down syndrome: from neurons to neural networks. Rev Neurosci 2022; 34:365-423. [PMID: 36170842 DOI: 10.1515/revneuro-2022-0067] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/28/2022] [Indexed: 11/15/2022]
Abstract
Down syndrome (DS), a genetic pathology caused by triplication of chromosome 21, is characterized by brain hypotrophy and impairment of cognition starting from infancy. While studies in mouse models of DS have elucidated the major neuroanatomical and neurochemical defects of DS, comparatively fewer investigations have focused on the electrophysiology of the DS brain. Electrical activity is at the basis of brain functioning. Therefore, knowledge of the way in which brain circuits operate in DS is fundamental to understand the causes of behavioral impairment and devise targeted interventions. This review summarizes the state of the art regarding the electrical properties of the DS brain, starting from individual neurons and culminating in signal processing in whole neuronal networks. The reported evidence derives from mouse models of DS and from brain tissues and neurons derived from individuals with DS. EEG data recorded in individuals with DS are also provided as a key tool to understand the impact of brain circuit alterations on global brain activity.
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Affiliation(s)
- Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
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5
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Kleschevnikov AM. Enhanced GIRK2 channel signaling in Down syndrome: A feasible role in the development of abnormal nascent neural circuits. Front Genet 2022; 13:1006068. [PMID: 36171878 PMCID: PMC9510977 DOI: 10.3389/fgene.2022.1006068] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 08/24/2022] [Indexed: 11/24/2022] Open
Abstract
The most distinctive feature of Down syndrome (DS) is moderate to severe cognitive impairment. Genetic, molecular, and neuronal mechanisms of this complex DS phenotype are currently under intensive investigation. It is becoming increasingly clear that the abnormalities arise from a combination of initial changes caused by triplication of genes on human chromosome 21 (HSA21) and later compensatory adaptations affecting multiple brain systems. Consequently, relatively mild initial cognitive deficits become pronounced with age. This pattern of changes suggests that one approach to improving cognitive function in DS is to target the earliest critical changes, the prevention of which can change the ‘trajectory’ of the brain development and reduce the destructive effects of the secondary alterations. Here, we review the experimental data on the role of KCNJ6 in DS-specific brain abnormalities, focusing on a putative role of this gene in the development of abnormal neural circuits in the hippocampus of genetic mouse models of DS. It is suggested that the prevention of these early abnormalities with pharmacological or genetic means can ameliorate cognitive impairment in DS.
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6
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Fatty Acids: A Safe Tool for Improving Neurodevelopmental Alterations in Down Syndrome? Nutrients 2022; 14:nu14142880. [PMID: 35889838 PMCID: PMC9323400 DOI: 10.3390/nu14142880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 02/06/2023] Open
Abstract
The triplication of chromosome 21 causes Down syndrome (DS), a genetic disorder that is characterized by intellectual disability (ID). The causes of ID start in utero, leading to impairments in neurogenesis, and continue into infancy, leading to impairments in dendritogenesis, spinogenesis, and connectivity. These defects are associated with alterations in mitochondrial and metabolic functions and precocious aging, leading to the early development of Alzheimer’s disease. Intense efforts are currently underway, taking advantage of DS mouse models to discover pharmacotherapies for the neurodevelopmental and cognitive deficits of DS. Many treatments that proved effective in mouse models may raise safety concerns over human use, especially at early life stages. Accumulating evidence shows that fatty acids, which are nutrients present in normal diets, exert numerous positive effects on the brain. Here, we review (i) the knowledge obtained from animal models regarding the effects of fatty acids on the brain, by focusing on alterations that are particularly prominent in DS, and (ii) the progress recently made in a DS mouse model, suggesting that fatty acids may indeed represent a useful treatment for DS. This scenario should prompt the scientific community to further explore the potential benefit of fatty acids for people with DS.
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7
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Giffin-Rao Y, Sheng J, Strand B, Xu K, Huang L, Medo M, Risgaard KA, Dantinne S, Mohan S, Keshan A, Daley RA, Levesque B, Amundson L, Reese R, Sousa AMM, Tao Y, Wang D, Zhang SC, Bhattacharyya A. Altered patterning of trisomy 21 interneuron progenitors. Stem Cell Reports 2022; 17:1366-1379. [PMID: 35623352 PMCID: PMC9214050 DOI: 10.1016/j.stemcr.2022.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 05/01/2022] [Accepted: 05/02/2022] [Indexed: 11/17/2022] Open
Abstract
Individuals with Down syndrome (DS; Ts21), the most common genetic cause of intellectual disability, have smaller brains that reflect fewer neurons at pre- and post-natal stages, implicating impaired neurogenesis during development. Our stereological analysis of adult DS cortex indicates a reduction of calretinin-expressing interneurons. Using Ts21 human induced pluripotent stem cells (iPSCs) and isogenic controls, we find that Ts21 progenitors generate fewer COUP-TFII+ progenitors with reduced proliferation. Single-cell RNA sequencing of Ts21 progenitors confirms the altered specification of progenitor subpopulations and identifies reduced WNT signaling. Activation of WNT signaling partially restores the COUP-TFII+ progenitor population in Ts21, suggesting that altered WNT signaling contributes to the defective development of cortical interneurons in DS.
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Affiliation(s)
| | - Jie Sheng
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Biostatistics and Medical Informatics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Bennett Strand
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Ke Xu
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Leslie Huang
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Margaret Medo
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | | | - Samuel Dantinne
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Sruti Mohan
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Aratrika Keshan
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Roger A Daley
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Bradley Levesque
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Lindsey Amundson
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Rebecca Reese
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - André M M Sousa
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Yunlong Tao
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Daifeng Wang
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Biostatistics and Medical Informatics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Su-Chun Zhang
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Neurology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Anita Bhattacharyya
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA.
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8
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Risgaard KA, Sorci IA, Mohan S, Bhattacharyya A. Meta-Analysis of Down Syndrome Cortical Development Reveals Underdeveloped State of the Science. Front Cell Neurosci 2022; 16:915272. [PMID: 35769326 PMCID: PMC9234119 DOI: 10.3389/fncel.2022.915272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/20/2022] [Indexed: 11/27/2022] Open
Abstract
Neurodevelopmental impairment contributes to the hallmark cognitive disability in individuals with Down syndrome (DS, trisomy 21, T21). The appearance of cognitive deficits in infancy suggests that alterations emerge during the earliest stages of neural development and continue throughout the lifespan in DS. Neural correlates of intellectual and language function include cortical structures, specifically temporal and frontal lobes that are smaller in DS. Yet, despite increased understanding of the DS cognitive-behavioral phenotype in childhood, there is very little structural and histological information to help explain the deficits. Consequently, attempts to effectively design therapeutic targets or interventions are limited. We present a systematic review of published research on cortical development in DS that reveals a paucity of studies that rigorously identify cellular features that may underlie the gross morphological deficits of the developing DS brain. We assessed 115 published reports retrieved through PubMed and other sources and found that only 23 reported histological and/or immunohistochemical data to define cell composition affected in DS post-mortem brain. Further, our analysis reveals that many reports have limited samples sizes and few DS samples, making it difficult to draw conclusions that are generally applicable to the DS population. Thus, the lack of replication and limited number of studies indicate that more developmentally focused research, ideally using equal numbers of age-matched samples in analyses, is needed to elucidate the cellular nature of smaller brain size in DS.
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Affiliation(s)
| | - Isabella A. Sorci
- Waisman Center, University of Wisconsin—Madison, Madison, WI, United States
| | - Sruti Mohan
- Waisman Center, University of Wisconsin—Madison, Madison, WI, United States
| | - Anita Bhattacharyya
- Waisman Center, University of Wisconsin—Madison, Madison, WI, United States
- Department of Cell and Regenerative Biology, School of Medicine and Pubic Health, University of Wisconsin—Madison, Madison, WI, United States
- *Correspondence: Anita Bhattacharyya
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9
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Kleschevnikov A. GIRK2 Channels in Down Syndrome and Alzheimer's Disease. Curr Alzheimer Res 2022; 19:819-829. [PMID: 36567290 DOI: 10.2174/1567205020666221223122110] [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: 08/13/2022] [Revised: 11/26/2022] [Accepted: 11/29/2022] [Indexed: 12/27/2022]
Abstract
Cognitive impairment in Down syndrome (DS) results from the abnormal expression of hundreds of genes. However, the impact of KCNJ6, a gene located in the middle of the 'Down syndrome critical region' of chromosome 21, seems to stand out. KCNJ6 encodes GIRK2 (KIR3.2) subunits of G protein-gated inwardly rectifying potassium channels, which serve as effectors for GABAB, m2, 5HT1A, A1, and many other postsynaptic metabotropic receptors. GIRK2 subunits are heavily expressed in neocortex, cerebellum, and hippocampus. By controlling resting membrane potential and neuronal excitability, GIRK2 channels may thus affect both synaptic plasticity and stability of neural circuits in the brain regions important for learning and memory. Here, we discuss recent experimental data regarding the role of KCNJ6/GIRK2 in neuronal abnormalities and cognitive impairment in models of DS and Alzheimer's disease (AD). The results compellingly show that signaling through GIRK2 channels is abnormally enhanced in mouse genetic models of Down syndrome and that partial suppression of GIRK2 channels with pharmacological or genetic means can restore synaptic plasticity and improve impaired cognitive functions. On the other hand, signaling through GIRK2 channels is downregulated in AD models, such as models of early amyloidopathy. In these models, reduced GIRK2 channel signaling promotes neuronal hyperactivity, causing excitatory-inhibitory imbalance and neuronal death. Accordingly, activation of GABAB/GIRK2 signaling by GIRK channel activators or GABAB receptor agonists may reduce Aβ-induced hyperactivity and subsequent neuronal death, thereby exerting a neuroprotective effect in models of AD.
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10
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Atypical electrophysiological and behavioral responses to diazepam in a leading mouse model of Down syndrome. Sci Rep 2021; 11:9521. [PMID: 33947925 PMCID: PMC8096846 DOI: 10.1038/s41598-021-89011-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 04/15/2021] [Indexed: 02/02/2023] Open
Abstract
Mounting evidence implicates dysfunctional GABAAR-mediated neurotransmission as one of the underlying causes of learning and memory deficits observed in the Ts65Dn mouse model of Down syndrome (DS). The specific origin and nature of such dysfunction is still under investigation, which is an issue with practical consequences to preclinical and clinical research, as well as to the care of individuals with DS and anxiety disorder or those experiencing seizures in emergency room settings. Here, we investigated the effects of GABAAR positive allosteric modulation (PAM) by diazepam on brain activity, synaptic plasticity, and behavior in Ts65Dn mice. We found Ts65Dn mice to be less sensitive to diazepam, as assessed by electroencephalography, long-term potentiation, and elevated plus-maze. Still, diazepam pre-treatment displayed typical effectiveness in reducing susceptibility and severity to picrotoxin-induced seizures in Ts65Dn mice. These findings fill an important gap in the understanding of GABAergic function in a key model of DS.
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11
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Hendrix JA, Amon A, Abbeduto L, Agiovlasitis S, Alsaied T, Anderson HA, Bain LJ, Baumer N, Bhattacharyya A, Bogunovic D, Botteron KN, Capone G, Chandan P, Chase I, Chicoine B, Cieuta-Walti C, DeRuisseau LR, Durand S, Esbensen A, Fortea J, Giménez S, Granholm AC, Hahn LJ, Head E, Hillerstrom H, Jacola LM, Janicki MP, Jasien JM, Kamer AR, Kent RD, Khor B, Lawrence JB, Lemonnier C, Lewanda AF, Mobley W, Moore PE, Nelson LP, Oreskovic NM, Osorio RS, Patterson D, Rasmussen SA, Reeves RH, Roizen N, Santoro S, Sherman SL, Talib N, Tapia IE, Walsh KM, Warren SF, White AN, Wong GW, Yi JS. Opportunities, barriers, and recommendations in down syndrome research. TRANSLATIONAL SCIENCE OF RARE DISEASES 2021; 5:99-129. [PMID: 34268067 PMCID: PMC8279178 DOI: 10.3233/trd-200090] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Recent advances in medical care have increased life expectancy and improved the quality of life for people with Down syndrome (DS). These advances are the result of both pre-clinical and clinical research but much about DS is still poorly understood. In 2020, the NIH announced their plan to update their DS research plan and requested input from the scientific and advocacy community. OBJECTIVE The National Down Syndrome Society (NDSS) and the LuMind IDSC Foundation worked together with scientific and medical experts to develop recommendations for the NIH research plan. METHODS NDSS and LuMind IDSC assembled over 50 experts across multiple disciplines and organized them in eleven working groups focused on specific issues for people with DS. RESULTS This review article summarizes the research gaps and recommendations that have the potential to improve the health and quality of life for people with DS within the next decade. CONCLUSIONS This review highlights many of the scientific gaps that exist in DS research. Based on these gaps, a multidisciplinary group of DS experts has made recommendations to advance DS research. This paper may also aid policymakers and the DS community to build a comprehensive national DS research strategy.
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Affiliation(s)
| | - Angelika Amon
- Deceased. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Leonard Abbeduto
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA; MIND Institute, University of California, Davis, CA, USA
| | | | - Tarek Alsaied
- Heart Institute Department of Pediatrics Cincinnati Children’s Hospital Medical Center University of Cincinnati, Cincinnati, OH, USA
| | | | | | - Nicole Baumer
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA; Down Syndrome Program, Developmental Medicine Center, Boston Children’s Hospital, Boston, MA, USA
| | - Anita Bhattacharyya
- Waisman Center, University of Wisconsin-Madison, Madison, WI, USA
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Dusan Bogunovic
- Department of Microbiology, Icahn School of Medicine at Mt. Sinai, New York, NY, USA; Department of Pediatrics, Icahn School of Medicine at Mt. Sinai, New York, NY; Precision Immunology Institute, Icahn School of Medicine at Mt. Sinai, New York, NY, USA; Mindich Child Health and Development Institute, Icahn School of Medicine at Mt. Sinai, New York, NY, USA
| | - Kelly N. Botteron
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Priya Chandan
- Department of Neurosurgery, Division of Physical Medicine and Rehabilitation, University of Louisville School of Medicine, Louisville, KY, USA
| | - Isabelle Chase
- Department of Pediatric Dentistry, Boston Children’s Hospital, Boston, MA, USA
| | - Brian Chicoine
- Advocate Medical Group Adult Down Syndrome Center, Park Ridge, IL, USA
| | | | | | | | - Anna Esbensen
- Department of Pediatrics, University of Cincinnati College of Medicine & Division of Developmental and Behavioral Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Juan Fortea
- Barcelona Down Medical Center, Fundació Catalana de Síndrome de Down, Barcelona, Spain; Sant Pau Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Biomedical Research Institute Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain; Center of Biomedical Investigation Network for Neurodegenerative Diseases, Madrid, Spain
| | - Sandra Giménez
- Multidisciplinary Sleep Unit, Respiratory Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Ann-Charlotte Granholm
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
- Department of Neurobiology, Care Sciences and Society (NVS), Karolinska Institutet, Stockholm, Sweden
| | - Laura J. Hahn
- Department of Speech and Hearing Science, University of Illinois Urbana Champaign, Champaign, IL, USA
| | - Elizabeth Head
- Department of Pathology and Laboratory Medicine, UC Irvine School of Medicine, Orange, CA, USA
| | | | - Lisa M. Jacola
- Department of Psychology, St Jude Children’s Research Hospital, Memphis, TN, USA
| | | | - Joan M. Jasien
- Division of Pediatric Neurology, Duke University Health System, Durham, NC, USA
| | - Angela R. Kamer
- Department of Periodontology and Implant Dentistry, New York University, College of Dentistry, New York, NY, USA
| | - Raymond D. Kent
- Waisman Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Bernard Khor
- Benaroy Research Institute at Virginia Mason, Seattle, WA, USA
| | - Jeanne B. Lawrence
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA, USA; Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA, USA
| | | | - Amy Feldman Lewanda
- Children s National Rare Disease Institute, Children’s National Health System, Washington, DC., USA
| | - William Mobley
- Department of Neurosciences, University of California, San Diego, CA, USA
| | - Paul E. Moore
- Division of Allergy, Immunology, and Pulmonology, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | | | - Nicolas M. Oreskovic
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA, USA; Department of Internal Medicine, Massachusetts General Hospital, Boston, Mass
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Ricardo S. Osorio
- Center for Brain Health, Department of Psychiatry, NYU Langone Medical Center, New York, NY, USA
| | - David Patterson
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
- Eleanor Roosevelt Institute, University of Denver, Denver, CO, USA; Department of Biological Sciences, University of Denver, Denver, CO, USA; Molecular and Cellular Biophysics Program, University of Denver, Denver, CO, USA
| | - Sonja A. Rasmussen
- Department of Pediatrics, University of Florida College of Medicine, Gainesville, FL; Department of Epidemiology, University of Florida College of Public Health and Health Professions and College of Medicine, Gainesville, FL
| | - Roger H. Reeves
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Nancy Roizen
- Department of Pediatrics, UH/Rainbow Babies and Children’s Hospital and Department of Pediatrics, Case Western Reserve University, Cleveland, OH, USA
| | - Stephanie Santoro
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
- Down Syndrome Program, Division of Medical Genetics and Metabolism, Department of Pediatrics, Massachusetts General Hospital, Boston, MA, USA
| | - Stephanie L. Sherman
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Nasreen Talib
- Division of General Pediatrics, Children’s Mercy Kansas City, 2401 Gillham Road, Kansas City, MO, USA
| | - Ignacio E. Tapia
- Sleep Center, Division of Pulmonary Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kyle M. Walsh
- Division of Neuro-epidemiology, Department of Neurosurgery, Duke University, Durham, NC, USA
| | - Steven F. Warren
- Institute for Life Span Studies, University of Kansas, Lawrence, KS, USA
| | - A. Nicole White
- Research Foundation, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Guang William Wong
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Center for Metabolism and Obesity Research, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - John S. Yi
- Division of Surgical Sciences, Department of Surgery, Duke University Medical Center, Durham, NC, USA
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12
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Kha TK, Doan BND. Evolution of synthetic strategies and design for synthesis of (−)-picrotoxinin. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.132022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Petrache AL, Khan AA, Nicholson MW, Monaco A, Kuta-Siejkowska M, Haider S, Hilton S, Jovanovic JN, Ali AB. Selective Modulation of α5 GABA A Receptors Exacerbates Aberrant Inhibition at Key Hippocampal Neuronal Circuits in APP Mouse Model of Alzheimer's Disease. Front Cell Neurosci 2020; 14:568194. [PMID: 33262690 PMCID: PMC7686552 DOI: 10.3389/fncel.2020.568194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/28/2020] [Indexed: 11/13/2022] Open
Abstract
Selective negative allosteric modulators (NAMs), targeting α5 subunit-containing GABAA receptors (GABAARs) as potential therapeutic targets for disorders associated with cognitive deficits, including Alzheimer's disease (AD), continually fail clinical trials. We investigated whether this was due to the change in the expression of α5 GABAARs, consequently altering synaptic function during AD pathogenesis. Using medicinal chemistry and computational modeling, we developed aqueous soluble hybrids of 6,6-dimethyl-3-(2-hydroxyethyl) thio-1-(thiazol-2-yl)-6,7-dihydro-2-benzothiophene-4(5H)-one, that demonstrated selective binding and high negative allosteric modulation, specifically for the α5 GABAAR subtypes in constructed HEK293 stable cell-lines. Using a knock-in mouse model of AD (APP NL-F/NL-F), which expresses a mutant form of human amyloid-β (Aβ), we performed immunofluorescence studies combined with electrophysiological whole-cell recordings to investigate the effects of our key molecule, α5-SOP002 in the hippocampal CA1 region. In aged APP NL-F/NL-F mice, selective preservation of α5 GABAARs was observed in, calretinin- (CR), cholecystokinin- (CCK), somatostatin- (SST) expressing interneurons, and pyramidal cells. Previously, we reported that CR dis-inhibitory interneurons, specialized in regulating other interneurons displayed abnormally high levels of synaptic inhibition in the APP NL-F/NL-F mouse model, here we show that this excessive inhibition was "normalized" to control values with bath-applied α5-SOP002 (1 μM). However, α5-SOP002, further impaired inhibition onto CCK and pyramidal cells that were already largely compromised by exhibiting a deficit of inhibition in the AD model. In summary, using a multi-disciplinary approach, we show that exposure to α5 GABAAR NAMs may further compromise aberrant synapses in AD. We, therefore, suggest that the α5 GABAAR is not a suitable therapeutic target for the treatment of AD or other cognitive deficits due to the widespread neuronal-networks that use α5 GABAARs.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Afia B Ali
- UCL School of Pharmacy, London, United Kingdom
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14
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Hamburg S, Rosch R, Startin CM, Friston KJ, Strydom A. Dynamic Causal Modeling of the Relationship between Cognition and Theta-alpha Oscillations in Adults with Down Syndrome. Cereb Cortex 2020; 29:2279-2290. [PMID: 30877793 PMCID: PMC6458903 DOI: 10.1093/cercor/bhz043] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 02/09/2019] [Indexed: 01/17/2023] Open
Abstract
Individuals with Down syndrome (DS) show high inter-subject variability in cognitive ability and have an ultra-high risk of developing dementia (90% lifetime prevalence). Elucidating factors underlying variability in cognitive function can inform us about intellectual disability (ID) and may improve our understanding of factors associated with later cognitive decline. Increased neuronal inhibition has been posited to contribute to ID in DS. Combining electroencephalography (EEG) with dynamic causal modeling (DCM) provides a non-invasive method for investigating excitatory/inhibitory mechanisms. Resting-state EEG recordings were obtained from 36 adults with DS with no evidence of cognitive decline. Theta–alpha activity (4–13 Hz) was characterized in relation to general cognitive ability (raw Kaufmann’s Brief Intelligence Test second Edition (KBIT-2) score). Higher KBIT-2 was associated with higher frontal alpha peak amplitude and higher theta–alpha band power across distributed regions. Modeling this association with DCM revealed intrinsic self-inhibition was the key network parameter underlying observed differences in 4–13 Hz power in relation to KBIT-2 and age. In particular, intrinsic self-inhibition in right V1 was negatively correlated with KBIT-2. Results suggest intrinsic self-inhibition within the alpha network is associated with individual differences in cognitive ability in adults with DS, and may provide a potential therapeutic target for cognitive enhancement.
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Affiliation(s)
- Sarah Hamburg
- Division of Psychiatry, Faculty of Brain Sciences, University College London, 149 Tottenham Court Road, London, UK.,Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, UK.,The London Down Syndrome Consortium (LonDownS), London, UK
| | - Richard Rosch
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.,Wellcome Centre for Human Neuroimaging, Institute of Neurology, University College London, 12 Queen Square, London, UK
| | - Carla Marie Startin
- Division of Psychiatry, Faculty of Brain Sciences, University College London, 149 Tottenham Court Road, London, UK.,Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, UK.,The London Down Syndrome Consortium (LonDownS), London, UK
| | - Karl John Friston
- Wellcome Centre for Human Neuroimaging, Institute of Neurology, University College London, 12 Queen Square, London, UK
| | - André Strydom
- Division of Psychiatry, Faculty of Brain Sciences, University College London, 149 Tottenham Court Road, London, UK.,Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, UK.,The London Down Syndrome Consortium (LonDownS), London, UK
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15
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García-Cerro S, Rueda N, Vidal V, Puente A, Campa V, Lantigua S, Narcís O, Velasco A, Bartesaghi R, Martínez-Cué C. Prenatal Administration of Oleic Acid or Linolenic Acid Reduces Neuromorphological and Cognitive Alterations in Ts65dn Down Syndrome Mice. J Nutr 2020; 150:1631-1643. [PMID: 32243527 DOI: 10.1093/jn/nxaa074] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 12/17/2019] [Accepted: 03/02/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The cognitive impairments that characterize Down syndrome (DS) have been attributed to brain hypocellularity due to neurogenesis impairment during fetal stages. Thus, enhancing prenatal neurogenesis in DS could prevent or reduce some of the neuromorphological and cognitive defects found in postnatal stages. OBJECTIVES As fatty acids play a fundamental role in morphogenesis and brain development during fetal stages, in this study, we aimed to enhance neurogenesis and the cognitive abilities of the Ts65Dn (TS) mouse model of DS by administering oleic or linolenic acid. METHODS In total, 85 pregnant TS females were subcutaneously treated from Embryonic Day (ED) 10 until Postnatal Day (PD) 2 with oleic acid (400 mg/kg), linolenic acid (500 mg/kg), or vehicle. All analyses were performed on their TS and Control (CO) male and female progeny. At PD2, we evaluated the short-term effects of the treatments on neurogenesis, cellularity, and brain weight, in 40 TS and CO pups. A total of 69 TS and CO mice were used to test the long-term effects of the prenatal treatments on cognition from PD30 to PD45, and on neurogenesis, cellularity, and synaptic markers, at PD45. Data were compared by ANOVAs. RESULTS Prenatal administration of oleic or linolenic acid increased the brain weight (+36.7% and +45%, P < 0.01), the density of BrdU (bromodeoxyuridine)- (+80% and +115%; P < 0.01), and DAPI (4',6-diamidino-2-phenylindole)-positive cells (+64% and +22%, P < 0.05) of PD2 TS mice with respect to the vehicle-treated TS mice. Between PD30 and PD45, TS mice prenatally treated with oleic or linolenic acid showed better cognitive abilities (+28% and +25%, P < 0.01) and a higher density of the postsynaptic marker PSD95 (postsynaptic density protein 95) (+65% and +44%, P < 0.05) than the vehicle-treated TS animals. CONCLUSION The beneficial cognitive and neuromorphological effects induced by oleic or linolenic acid in TS mice suggest that they could be promising pharmacotherapies for DS-associated cognitive deficits.
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Affiliation(s)
- Susana García-Cerro
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Cantabria, Spain
| | - Noemí Rueda
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Cantabria, Spain
| | - Verónica Vidal
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Cantabria, Spain
| | - Alba Puente
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Cantabria, Spain
| | - Víctor Campa
- Institute of Molecular Biology and Biomedicine (IBTECC), Santander, Cantabria, Spain
| | - Sara Lantigua
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Cantabria, Spain
| | - Oriol Narcís
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Cantabria, Spain
| | - Ana Velasco
- Department of Biochemistry and Molecular Biology, Institute of Neurosciences of Castilla and Leon (INCYL), University of Salamanca, Institute of Biomedical Research of Salamanca (IBSAL), Salamanca, Spain
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Carmen Martínez-Cué
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Cantabria, Spain
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16
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Duchon A, Gruart A, Albac C, Delatour B, Zorrilla de San Martin J, Delgado-García JM, Hérault Y, Potier MC. Long-lasting correction of in vivo LTP and cognitive deficits of mice modelling Down syndrome with an α5-selective GABA A inverse agonist. Br J Pharmacol 2020; 177:1106-1118. [PMID: 31652355 PMCID: PMC7042104 DOI: 10.1111/bph.14903] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 09/12/2019] [Accepted: 09/15/2019] [Indexed: 12/19/2022] Open
Abstract
Background and Purpose Excessive GABAergic inhibition contributes to cognitive dysfunctions in Down syndrome (DS). Selective negative allosteric modulators (NAMs) of α5‐containing GABAA receptors such as the α5 inverse agonist (α5IA) restore learning and memory deficits in Ts65Dn mice, a model of DS. In this study we have assessed the long‐lasting effects of α5IA on in vivo LTP and behaviour in Ts65Dn mice. Experimental Approach We made in vivo LTP recordings for six consecutive days in freely moving Ts65Dn mice and their wild‐type littermates, treated with vehicle or α5IA. In parallel, Ts65Dn mice were assessed by various learning and memory tests (Y maze, Morris water maze, or the novel object recognition) for up to 7 days, following one single injection of α5IA or vehicle. Key Results LTP was not evoked in vivo in Ts65Dn mice at hippocampal CA3‐CA1 synapses. However, this deficit was sustainably reversed for at least six consecutive days following a single injection of α5IA. This long‐lasting effect of α5IA was also observed when assessing working and long‐term memory deficits in Ts65Dn mice. Conclusion and Implications We show for the first time in vivo LTP deficits in Ts65Dn mice. These deficits were restored for at least 6 days following acute treatment with α5IA and might be the substrate for the long‐lasting pharmacological effects of α5IA on spatial working and long‐term recognition and spatial memory tasks. Our results demonstrate the relevance of negative allosteric modulators of α5‐containing GABAA receptors to the treatment of cognitive deficits associated with DS.
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Affiliation(s)
- Arnaud Duchon
- Translational Medicine and Neurogenetics, 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, U1258, Illkirch, France.,Neuropôle, Université de Strasbourg, Illkirch, France
| | - Agnès Gruart
- División de Neurociencias, Universidad Pablo de Olavide, Seville, Spain
| | - Christelle Albac
- Institut du Cerveau et de la Moelle épinière, Hôpital de la Pitié-Salpêtrière, Paris, France.,Institut National de la Santé et de la Recherche Médicale, U1127, Hôpital de la Pitié-Salpêtrière, Paris, France.,Centre National de la Recherche Scientifique, UMR7225, Hôpital de la Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Benoît Delatour
- Institut du Cerveau et de la Moelle épinière, Hôpital de la Pitié-Salpêtrière, Paris, France.,Institut National de la Santé et de la Recherche Médicale, U1127, Hôpital de la Pitié-Salpêtrière, Paris, France.,Centre National de la Recherche Scientifique, UMR7225, Hôpital de la Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Javier Zorrilla de San Martin
- Institut du Cerveau et de la Moelle épinière, Hôpital de la Pitié-Salpêtrière, Paris, France.,Institut National de la Santé et de la Recherche Médicale, U1127, Hôpital de la Pitié-Salpêtrière, Paris, France.,Centre National de la Recherche Scientifique, UMR7225, Hôpital de la Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | | | - Yann Hérault
- Translational Medicine and Neurogenetics, 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, U1258, Illkirch, France.,Neuropôle, Université de Strasbourg, Illkirch, France
| | - Marie-Claude Potier
- Institut du Cerveau et de la Moelle épinière, Hôpital de la Pitié-Salpêtrière, Paris, France.,Institut National de la Santé et de la Recherche Médicale, U1127, Hôpital de la Pitié-Salpêtrière, Paris, France.,Centre National de la Recherche Scientifique, UMR7225, Hôpital de la Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
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17
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Γ-Aminobutyric acid in adult brain: an update. Behav Brain Res 2019; 376:112224. [DOI: 10.1016/j.bbr.2019.112224] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/09/2019] [Accepted: 09/09/2019] [Indexed: 01/21/2023]
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18
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Rueda N, Flórez J, Dierssen M, Martínez-Cué C. Translational validity and implications of pharmacotherapies in preclinical models of Down syndrome. PROGRESS IN BRAIN RESEARCH 2019; 251:245-268. [PMID: 32057309 DOI: 10.1016/bs.pbr.2019.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Neurodevelopmental disorders are challenging to study in the laboratory, and despite a large investment, few novel treatments have been developed in the last decade. While animal models have been valuable in elucidating disease mechanisms and in providing insights into the function of specific genes, the predictive validity of preclinical models to test potential therapies has been questioned. In the last two decades, diverse new murine models of Down syndrome (DS) have been developed and numerous studies have demonstrated neurobiological alterations that could be responsible for the cognitive and behavioral phenotypes found in this syndrome. In many cases, similar alterations were found in murine models and in individuals with DS, although several phenotypes shown in animals have yet not been confirmed in the human condition. Some of the neurobiological alterations observed in mice have been proposed to account for their changes in cognition and behavior, and have received special attention because of being putative therapeutic targets. Those include increased oxidative stress, altered neurogenesis, overexpression of the Dyrk1A gene, GABA-mediated overinhibition and Alzheimer's disease-related neurodegeneration. Subsequently, different laboratories have tested the efficacy of pharmacotherapies targeting these alterations. Unfortunately, animal models are limited in their ability to mimic the extremely complex process of human neurodevelopment and neuropathology. Therefore, the safety and efficacy identified in animal studies are not always translated to humans, and most of the drugs tested have not demonstrated any positive effect or very limited efficacy in clinical trials. Despite their limitations, though, animal trials give us extremely valuable information for developing and testing drugs for human use that cannot be obtained from molecular or cellular experiments alone. This chapter reviews some of these therapeutic approaches and discusses some reasons that could account for the discrepancy between the findings in mouse models of DS and in humans, including: (i) the incomplete resemble of the genetic alterations of available mouse models of DS and human trisomy 21, (ii) the lack of evidence that some of the phenotypic alterations found in mice (e.g., GABA-mediated overinhibition, and alterations in adult neurogenesis) are also present in DS individuals, and (iii) the inaccuracy and/or inadequacy of the methods used in clinical trials to detect changes in the cognitive and behavioral functions of people with DS. Despite the shortcomings of animal models, animal experimentation remains an invaluable tool in developing drugs. Thus, we will also discuss how to increase predictive validity of mouse models.
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Affiliation(s)
- Noemí Rueda
- Department of Physiology and Pharmacology, University of Cantabria, Santander, Spain
| | - Jesús Flórez
- Department of Physiology and Pharmacology, University of Cantabria, Santander, Spain
| | - Mara Dierssen
- Cellular and Systems Neurobiology, Systems Biology Program, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology, Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Carmen Martínez-Cué
- Department of Physiology and Pharmacology, School of Medicine, University of Cantabria, Santander, Spain.
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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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Enhanced Dendritic Inhibition and Impaired NMDAR Activation in a Mouse Model of Down Syndrome. J Neurosci 2019; 39:5210-5221. [PMID: 31000585 DOI: 10.1523/jneurosci.2723-18.2019] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 11/21/2022] Open
Abstract
Down syndrome (DS) or Trisomy 21 is a developmental disorder leading to cognitive deficits, including disruption of hippocampus-dependent learning and memory. Enhanced inhibition has been suggested to underlie these deficits in DS based on studies using the Ts65Dn mouse model. Here we show that, in this mouse model, GABAergic synaptic inhibition onto dendrites of hippocampal pyramidal cells is increased. By contrast, somatic inhibition was not altered. In addition, synaptic NMDAR currents were reduced. Furthermore, dendritic inhibition was mediated via nonlinear α5-subunit containing GABAARs that closely matched the kinetics and voltage dependence of NMDARs. Thus, enhanced dendritic inhibition and reduced NMDA currents strongly decreased burst-induced NMDAR-mediated depolarization and impaired LTP induction. Finally, selective reduction of α5-GABAAR-mediated inhibition rescued both burst-induced synaptic NMDAR activation and synaptic plasticity. These results demonstrate that reduced synaptic NMDAR activation and synaptic plasticity in the Ts65Dn mouse model of DS can be corrected by specifically targeting nonlinear dendritic inhibition.SIGNIFICANCE STATEMENT Mild to moderate intellectual disability is a prominent feature of Down syndrome. Previous studies in mouse models suggest that increased synaptic inhibition is a main factor for decreased synaptic plasticity, the cellular phenomenon underlying memory. The present study shows that increased inhibition specifically onto dendrites together with reduced NMDAR content in excitatory synapses may be the cause. Reducing a slow nonlinear component that is specific to dendritic inhibitory inputs and mediated by α5 subunit-containing GABAA receptors rescues both NMDAR activation and synaptic plasticity.
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21
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Mohamad FH, Has ATC. The α5-Containing GABA A Receptors-a Brief Summary. J Mol Neurosci 2019; 67:343-351. [PMID: 30607899 DOI: 10.1007/s12031-018-1246-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 12/17/2018] [Indexed: 12/21/2022]
Abstract
GABAA receptors are the major inhibitory neurotransmitter receptor in the human brain. The receptors are assembled from combination of protein subunits in pentameric complex which may consist of α1-6, β1-3, γ1-3, ρ1-3, δ, ε, θ, or π subunits. There are a theoretical > 150,000 possible assemblies and arrangements of GABAA subunits, although only a few combinations have been found in human with the most dominant consists of 2α1, 2β2, and 1γ2 in a counterclockwise arrangement as seen from the synaptic cleft. The receptors also possess binding sites for various unrelated substances including benzodiazepines, barbiturates, and anesthetics. The α5-containing GABAARs only make up ≤ 5% of the entire receptor population, but up to 25% of the receptor subtype is located in the crucial learning and memory-associated area of the brain-the hippocampus, which has ignited myriads of hypotheses and theories in regard to its role. As well as exhibiting synaptic phasic inhibition, the α5-containing receptors are also extrasynaptic and mediate tonic inhibition with continuously occurring smaller amplitude. Studies on negative-allosteric modulators for reducing this tonic inhibition have been shown to enhance learning and memory in neurological disorders such as schizophrenia, Down syndrome, and autism with a possible alternative benzodiazepine binding site. Therefore, a few α5 subunit-specific compounds have been developed to address these pharmacological needs. With its small population, the α5-containing receptors could be the key and also the answer for many untreated cognitive dysfunctions and disorders.
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Affiliation(s)
- Fatin H Mohamad
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kampus Kesihatan, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Ahmad Tarmizi Che Has
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kampus Kesihatan, 16150, Kubang Kerian, Kelantan, Malaysia.
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22
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Golovko AI, Ivanov MB, Golovko ES, Dolgo-Saburov VB, Zatsepin EP. The Neurochemical Mechanisms of the Pharmacological Activities of Inverse Agonists of the Benzodiazepine Binding Site. NEUROCHEM J+ 2018. [DOI: 10.1134/s1819712418030042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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23
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Zhao X, Bhattacharyya A. Human Models Are Needed for Studying Human Neurodevelopmental Disorders. Am J Hum Genet 2018; 103:829-857. [PMID: 30526865 DOI: 10.1016/j.ajhg.2018.10.009] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 10/09/2018] [Indexed: 12/19/2022] Open
Abstract
The analysis of animal models of neurological disease has been instrumental in furthering our understanding of neurodevelopment and brain diseases. However, animal models are limited in revealing some of the most fundamental aspects of development, genetics, pathology, and disease mechanisms that are unique to humans. These shortcomings are exaggerated in disorders that affect the brain, where the most significant differences between humans and animal models exist, and could underscore failures in targeted therapeutic interventions in affected individuals. Human pluripotent stem cells have emerged as a much-needed model system for investigating human-specific biology and disease mechanisms. However, questions remain regarding whether these cell-culture-based models are sufficient or even necessary. In this review, we summarize human-specific features of neurodevelopment and the most common neurodevelopmental disorders, present discrepancies between animal models and human diseases, demonstrate how human stem cell models can provide meaningful information, and discuss the challenges that exist in our pursuit to understand distinctively human aspects of neurodevelopment and brain disease. This information argues for a more thoughtful approach to disease modeling through consideration of the valuable features and limitations of each model system, be they human or animal, to mimic disease characteristics.
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Affiliation(s)
- Xinyu Zhao
- Waisman Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA; Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA.
| | - Anita Bhattacharyya
- Waisman Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA; Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA.
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García-Cerro S, Vidal V, Lantigua S, Berciano MT, Lafarga M, Ramos-Cabrer P, Padro D, Rueda N, Martínez-Cué C. Cerebellar alterations in a model of Down syndrome: The role of the Dyrk1A gene. Neurobiol Dis 2018; 110:206-217. [PMID: 29221819 DOI: 10.1016/j.nbd.2017.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 11/13/2017] [Accepted: 12/04/2017] [Indexed: 01/31/2023] Open
Abstract
Down syndrome (DS) is characterized by a marked reduction in the size of the brain and cerebellum. These changes play an important role in the motor alterations and cognitive disabilities observed in this condition. The Ts65Dn (TS) mouse, the most commonly used model of DS, reflects many DS phenotypes, including alterations in cerebellar morphology. One of the genes that is overexpressed in both individuals with DS and TS mice is DYRK1A/Dyrk1A (dual-specificity tyrosine-(Y)-phosphorylation regulated kinase 1A), which has been implicated in the altered cerebellar structural and functional phenotypes observed in both populations. The aim of this study was to evaluate the effect of Dyrk1A on different alterations observed in the cerebellum of TS animals. TS mice were crossed with Dyrk1A +/- KO mice to obtain mice with a triplicate segment of Mmu16 that included Dyrk1A (TS +/+/+), mice with triplicate copies of the same genes that carried only two copies of Dyrk1A (TS +/+/-), euploid mice that expressed a normal dose of Dyrk1A (CO +/+) and CO animals with a single copy of Dyrk1A (CO +/-). Male mice were used for all experiments. The normalization of the Dyrk1A gene dosage did not rescue the reduced cerebellar volume. However, it increased the size of the granular and molecular layers, the densities of granular and Purkinje cells, and dendritic arborization. Furthermore, it improved the excitatory/inhibitory balance and walking pattern of TS +/+/- mice. These results support the hypothesis that Dyrk1A is involved in some of the structural and functional cerebellar phenotypes observed in the TS mouse model.
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Affiliation(s)
- Susana García-Cerro
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander 39011, Spain
| | - Verónica Vidal
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander 39011, Spain
| | - Sara Lantigua
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander 39011, Spain
| | - Maria Teresa Berciano
- Department of Anatomy and Cell Biology and CIBERNED, University of Cantabria-IDIVAL, Santander 39011, Spain
| | - Miguel Lafarga
- Department of Anatomy and Cell Biology and CIBERNED, University of Cantabria-IDIVAL, Santander 39011, Spain
| | - Pedro Ramos-Cabrer
- Molecular Imaging Unit, CIC BiomaGUNE, Donostia-San Sebastian 20009, Spain; Ikerbasque, The Basque Foundation for Science, Bilbao 48013, Spain
| | - Daniel Padro
- Molecular Imaging Unit, CIC BiomaGUNE, Donostia-San Sebastian 20009, Spain
| | - Noemí Rueda
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander 39011, Spain
| | - Carmen Martínez-Cué
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander 39011, Spain.
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Zorrilla de San Martin J, Delabar JM, Bacci A, Potier MC. GABAergic over-inhibition, a promising hypothesis for cognitive deficits in Down syndrome. Free Radic Biol Med 2018; 114:33-39. [PMID: 28993272 DOI: 10.1016/j.freeradbiomed.2017.10.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 10/01/2017] [Accepted: 10/04/2017] [Indexed: 12/31/2022]
Abstract
Down syndrome (DS), also known as trisomy 21, is the most common genetic cause of intellectual disability. It is also a model human disease for exploring consequences of gene dosage imbalance on complex phenotypes. Learning and memory impairments linked to intellectual disabilities in DS could result from synaptic plasticity deficits and excitatory-inhibitory alterations leading to changes in neuronal circuitry in the brain of affected individuals. Increasing number of studies in mouse and cellular models converge towards the assumption that excitatory-inhibitory imbalance occurs in DS, likely early during development. Thus increased inhibition appears to be a common trend that could explain synaptic and circuit disorganization. Interestingly using several potent pharmacological tools, preclinical studies strongly demonstrated that cognitive deficits could be restored in mouse models of DS. Clinical trials have not yet provided robust data for therapeutic application and additional studies are needed. Here we review the literature and our own published work emphasizing the over-inhibition hypothesis in DS and their links with gene dosage imbalance paving the way for future basic and clinical research.
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Affiliation(s)
- Javier Zorrilla de San Martin
- INSERM U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France
| | - Jean-Maurice Delabar
- INSERM U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France
| | - Alberto Bacci
- INSERM U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France
| | - Marie-Claude Potier
- INSERM U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.
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26
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Caraci F, Iulita MF, Pentz R, Flores Aguilar L, Orciani C, Barone C, Romano C, Drago F, Cuello AC. Searching for new pharmacological targets for the treatment of Alzheimer's disease in Down syndrome. Eur J Pharmacol 2017; 817:7-19. [DOI: 10.1016/j.ejphar.2017.10.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 09/26/2017] [Accepted: 10/04/2017] [Indexed: 11/26/2022]
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27
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GABA A receptor subunit deregulation in the hippocampus of human foetuses with Down syndrome. Brain Struct Funct 2017; 223:1501-1518. [PMID: 29168008 PMCID: PMC5869939 DOI: 10.1007/s00429-017-1563-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 11/05/2017] [Indexed: 11/01/2022]
Abstract
The function, regulation and cellular distribution of GABAA receptor subunits have been extensively documented in the adult rodent brain and are linked to numerous neurological disorders. However, there is a surprising lack of knowledge on the cellular (sub-) distribution of GABAA receptor subunits and of their expressional regulation in developing healthy and diseased foetal human brains. To propose a role for GABAA receptor subunits in neurodevelopmental disorders, we studied the developing hippocampus of normal and Down syndrome foetuses. Among the α1-3 and γ2 subunits probed, we find significantly altered expression profiles of the α1, α3 and γ2 subunits in developing Down syndrome hippocampi, with the α3 subunit being most affected. α3 subunits were selectively down-regulated in all hippocampal subfields and developmental periods tested in Down syndrome foetuses, presenting a developmental mismatch by their adult-like distribution in early foetal development. We hypothesized that increased levels of the amyloid precursor protein (APP), and particularly its neurotoxic β-amyloid (1-42) fragment, could disrupt α3 gene expression, likely by facilitating premature neuronal differentiation. Indeed, we find increased APP content in the hippocampi of the Down foetuses. In a corresponding cellular model, soluble β-amyloid (1-42) administered to cultured SH-SY5Y neuroblastoma cells, augmented by retinoic acid-induced differentiation towards a neuronal phenotype, displayed a reduction in α3 subunit levels. In sum, this study charts a comprehensive regional and subcellular map of key GABAA receptor subunits in identified neuronal populations in the hippocampus of healthy and Down syndrome foetuses and associates increased β-amyloid load with discordant down-regulation of α3 subunits.
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28
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Benke D, Möhler H. Impact on GABA systems in monogenetic developmental CNS disorders: Clues to symptomatic treatment. Neuropharmacology 2017; 136:46-55. [PMID: 28764992 DOI: 10.1016/j.neuropharm.2017.07.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 07/26/2017] [Accepted: 07/28/2017] [Indexed: 12/26/2022]
Abstract
Animal studies of several single-gene disorders demonstrate that reversing the molecular signaling deficits can result in substantial symptomatic improvements in function. Focusing on the ratio of excitation to inhibition as a potential pathophysiological hallmark, seven single-gene developmental CNS disorders are reviewed which are characterized by a striking dysregulation of neuronal inhibition. Deficits in inhibition and excessive inhibition are found. The examples of developmental disorders encompass Neurofibromatosis type 1, Fragile X syndrome, Rett syndrome, Dravet syndrome including autism-like behavior, NONO-mutation-induced intellectual disability, Succinic semialdehyde dehydrogenase deficiency and Congenital nystagmus due to FRMD7 mutations. The phenotype/genotype correlations observed in animal models point to potential treatment options and will continue to inspire clinical research. Three drugs are presently in clinical trials: acamprosate and ganoxolon for Fragile X syndrome and SGS-742 for SSADH deficiency. This article is part of the "Special Issue Dedicated to Norman G. Bowery".
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Affiliation(s)
- Dietmar Benke
- Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Neuroscience Center Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Drug Discovery Network Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| | - Hanns Möhler
- Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Neuroscience Center Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH), Vladimir-Prelog-Weg 10, 8023 Zurich, Switzerland.
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29
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Vidal V, García-Cerro S, Martínez P, Corrales A, Lantigua S, Vidal R, Rueda N, Ozmen L, Hernández MC, Martínez-Cué C. Decreasing the Expression of GABA A α5 Subunit-Containing Receptors Partially Improves Cognitive, Electrophysiological, and Morphological Hippocampal Defects in the Ts65Dn Model of Down Syndrome. Mol Neurobiol 2017; 55:4745-4762. [PMID: 28717969 DOI: 10.1007/s12035-017-0675-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/27/2017] [Indexed: 12/31/2022]
Abstract
Trisomy 21 or Down syndrome (DS) is the most common cause of intellectual disability of a genetic origin. The Ts65Dn (TS) mouse, which is the most commonly used and best-characterized mouse model of DS, displays many of the cognitive, neuromorphological, and biochemical anomalies that are found in the human condition. One of the mechanisms that have been proposed to be responsible for the cognitive deficits in this mouse model is impaired GABA-mediated inhibition. Because of the well-known modulatory role of GABAA α5 subunit-containing receptors in cognitive processes, these receptors are considered to be potential targets for improving the intellectual disability in DS. The chronic administration of GABAA α5-negative allosteric modulators has been shown to be procognitive without anxiogenic or proconvulsant side effects. In the present study, we use a genetic approach to evaluate the contribution of GABAA α5 subunit-containing receptors to the cognitive, electrophysiological, and neuromorphological deficits in TS mice. We show that reducing the expression of GABAA α5 receptors by deleting one or two copies of the Gabra5 gene in TS mice partially ameliorated the cognitive impairments, improved long-term potentiation, enhanced neural differentiation and maturation, and normalized the density of the GABAergic synapse markers. Reducing the gene dosage of Gabra5 in TS mice did not induce motor alterations and anxiety or affect the viability of the mice. Our results provide further evidence of the role of GABAA α5 receptor-mediated inhibition in cognitive impairment in the TS mouse model of DS.
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Affiliation(s)
- Verónica Vidal
- Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad deCantabria, Santander, Spain
| | - Susana García-Cerro
- Departamento de Fundamentos Clínicos, Unidad de Farmacología, Universitat de Barcelona, Barcelona, Spain
| | - Paula Martínez
- Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad deCantabria, Santander, Spain
| | - Andrea Corrales
- Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad deCantabria, Santander, Spain
| | - Sara Lantigua
- Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad deCantabria, Santander, Spain
| | - Rebeca Vidal
- Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad deCantabria, Santander, Spain.,Instituto de Biomedicina y Biotecnología de Cantabria, IBBTEC (Universidad de Cantabria, CSIC, SODERCAN), Santander, Spain.,Centro de Investigacion Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Noemí Rueda
- Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad deCantabria, Santander, Spain
| | - Laurence Ozmen
- Pharma Research and Early Development, Hoffman-La Roche Ltd., Basel, Switzerland
| | | | - Carmen Martínez-Cué
- Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad deCantabria, Santander, Spain.
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Milenkovic I, Jarc J, Dassler E, Aronica E, Iyer A, Adle-Biassette H, Scharrer A, Reischer T, Hainfellner JA, Kovacs GG. The physiological phosphorylation of tau is critically changed in fetal brains of individuals with Down syndrome. Neuropathol Appl Neurobiol 2017; 44:314-327. [PMID: 28455903 DOI: 10.1111/nan.12406] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 03/17/2017] [Accepted: 04/15/2017] [Indexed: 01/15/2023]
Abstract
AIMS Down syndrome (DS) is a common cause of mental retardation accompanied by cognitive impairment. Comprehensive studies suggested a link between development and ageing, as nearly all individuals with DS develop Alzheimer disease (AD)-like pathology. However, there is still a paucity of data on tau in early DS to support this notion. METHODS Using morphometric immunohistochemistry we compared tau phosphorylation in normal brains and in brains of individuals with DS from early development until early postnatal life. RESULTS We observed in DS a critical loss of physiological phosphorylation of tau. Rhombencephalic structures showed prominent differences between controls and DS using antibodies AT8 (Ser-202/Thr-205) and AT180 (Thr-231). In contrast, in the subiculum only a small portion of controls deviated from DS using antibodies AT100 (Thr-212/Ser-214) and AT270 (Thr-181). With exception of the subiculum, phosphorylation-independent tau did not differ between groups, as confirmed by immunostaining for the HT-7 antibody (epitope between 159 and 163 of the human tau) as well. DISCUSSION Our observations suggest functional tau disturbance in DS brains during development, rather than axonal loss. This supports the role of tau as a further important player in the pathophysiology of cognitive impairment in DS and related AD.
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Affiliation(s)
- I Milenkovic
- Department of Neurology, Medical University of Vienna, Vienna, Austria.,Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - J Jarc
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - E Dassler
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - E Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, The Netherlands.,SEIN - Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, The Netherlands
| | - A Iyer
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - H Adle-Biassette
- Inserm U1141, Paris, France.,Univ Paris Diderot, Sorbonne Paris Cité, UMRS 676, Paris, France.,Lariboisière Hospital, APHP, Paris, France
| | - A Scharrer
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - T Reischer
- Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria
| | - J A Hainfellner
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
| | - G G Kovacs
- Institute of Neurology, Neurodegeneration Research Group, Medical University of Vienna, Vienna, Austria
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31
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Kleschevnikov AM, Yu J, Kim J, Lysenko LV, Zeng Z, Yu YE, Mobley WC. Evidence that increased Kcnj6 gene dose is necessary for deficits in behavior and dentate gyrus synaptic plasticity in the Ts65Dn mouse model of Down syndrome. Neurobiol Dis 2017; 103:1-10. [PMID: 28342823 DOI: 10.1016/j.nbd.2017.03.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/09/2017] [Accepted: 03/21/2017] [Indexed: 11/15/2022] Open
Abstract
Down syndrome (DS), trisomy 21, is caused by increased dose of genes present on human chromosome 21 (HSA21). The gene-dose hypothesis argues that a change in the dose of individual genes or regulatory sequences on HSA21 is necessary for creating DS-related phenotypes, including cognitive impairment. We focused on a possible role for Kcnj6, the gene encoding Kir3.2 (Girk2) subunits of a G-protein-coupled inwardly-rectifying potassium channel. This gene resides on a segment of mouse Chromosome 16 that is present in one extra copy in the genome of the Ts65Dn mouse, a well-studied genetic model of DS. Kir3.2 subunit-containing potassium channels serve as effectors for a number of postsynaptic metabotropic receptors including GABAB receptors. Several studies raise the possibility that increased Kcnj6 dose contributes to synaptic and cognitive abnormalities in DS. To assess directly a role for Kcnj6 gene dose in cognitive deficits in DS, we produced Ts65Dn mice that harbor only 2 copies of Kcnj6 (Ts65Dn:Kcnj6++- mice). The reduction in Kcnj6 gene dose restored to normal the hippocampal level of Kir3.2. Long-term memory, examined in the novel object recognition test with the retention period of 24h, was improved to the level observed in the normosomic littermate control mice (2N:Kcnj6++). Significantly, both short-term and long-term potentiation (STP and LTP) was improved to control levels in the dentate gyrus (DG) of the Ts65Dn:Kcnj6++- mouse. In view of the ability of fluoxetine to suppress Kir3.2 channels, we asked if fluoxetine-treated DG slices of Ts65Dn:Kcnj6+++ mice would rescue synaptic plasticity. Fluoxetine increased STP and LTP to control levels. These results are evidence that increased Kcnj6 gene dose is necessary for synaptic and cognitive dysfunction in the Ts65Dn mouse model of DS. Strategies aimed at pharmacologically reducing channel function should be explored for enhancing cognition in DS.
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Affiliation(s)
- Alexander M Kleschevnikov
- Department of Neurosciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
| | - Jessica Yu
- Department of Neurosciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Jeesun Kim
- Department of Neurosciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Larisa V Lysenko
- Department of Neurosciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA; Academy of Biology and Biotechnology of Southern Federal University, 194/1 Stachki Str, Rostov-na-Donu 344090, Russian Federation
| | - Zheng Zeng
- Department of Neurosciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - 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
| | - William C Mobley
- Department of Neurosciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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32
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Abstract
Learning and memory are dependent on interactive excitatory and inhibitory mechanisms. In this review, we discuss a mechanism called disinhibition, which is the release of an inhibitory constraint that effectively results in an increased activity in the target neurons (for example, principal or projection neurons). We focus on discussing the role of disinhibition in learning and memory at a basic level and in disease models with cognitive deficits and highlight a strategy to reverse cognitive deficits caused by excess inhibition, through disinhibition of α5-containing GABA
A receptors mediating tonic inhibition in the hippocampus, based on subtype-selective negative allosteric modulators as a novel class of drugs.
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Affiliation(s)
- Hanns Möhler
- Institute of Pharmacology, University of Zurich, Zurich, Switzerland; Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology Zurich, Zurich, Switzerland
| | - Uwe Rudolph
- Laboratory of Genetic Neuropharmacology, McLean Hospital, Belmont, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA
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33
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Zaki ME, El-Bassyouni HT, Tosson AM, Youness E, Hussein J. Coenzyme Q10 and pro-inflammatory markers in children with Down syndrome: clinical and biochemical aspects. JORNAL DE PEDIATRIA (VERSÃO EM PORTUGUÊS) 2017. [DOI: 10.1016/j.jpedp.2016.04.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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34
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Zaki ME, El-Bassyouni HT, Tosson AMS, Youness E, Hussein J. Coenzyme Q10 and pro-inflammatory markers in children with Down syndrome: clinical and biochemical aspects. J Pediatr (Rio J) 2017; 93:100-104. [PMID: 27770619 DOI: 10.1016/j.jped.2016.04.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 04/18/2016] [Accepted: 04/27/2016] [Indexed: 12/26/2022] Open
Abstract
OBJECTIVE Evidence of oxidative stress was reported in individuals with Down syndrome. There is a growing interest in the contribution of the immune system in Down syndrome. The aim of this study is to evaluate the coenzyme Q10 and selected pro-inflammatory markers such as interleukin 6 and tumor necrosis factor α in children with Down syndrome. METHODS Eighty-six children (5-8 years of age) were enrolled in this case-control study from two public institutions. At the time of sampling, the patients and controls suffered from no acute or chronic illnesses and received no therapies or supplements. The levels of interleukin 6, tumor necrosis factor α, coenzyme Q10, fasting blood glucose, and intelligence quotient were measured. RESULTS Forty-three young Down syndrome children and forty-three controls were included over a period of eight months (January-August 2014). Compared with the control group, the Down syndrome patients showed significant increase in interleukin 6 and tumor necrosis factor α (p=0.002), while coenzyme Q10 was significantly decreased (p=0.002). Also, body mass index and fasting blood glucose were significantly increased in patients. There was a significantly positive correlation between coenzyme Q10 and intelligence quotient levels, as well as between interleukin 6 and tumor necrosis factor α. CONCLUSION Interleukin 6 and tumor necrosis factor α levels in young children with Down syndrome may be used as biomarkers reflecting the neurodegenerative process in them. Coenzyme Q10 might have a role as a good supplement in young children with Down syndrome to ameliorate the neurological symptoms.
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Affiliation(s)
- Moushira E Zaki
- National Research Centre, Medical Research Division, Biological Anthropology Department, Cairo, Egypt
| | - Hala T El-Bassyouni
- National Research Centre, Human Genetics and Genome Research Division, Clinical Genetics Department, Cairo, Egypt
| | - Angie M S Tosson
- Cairo University, Faculty of Medicine, Pediatrics Department, Cairo, Egypt.
| | - Eman Youness
- National Research Centre, Medical Research Division, Medical Biochemistry Department, Cairo, Egypt
| | - Jihan Hussein
- National Research Centre, Medical Research Division, Medical Biochemistry Department, Cairo, Egypt
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Tuk B. Overstimulation of the inhibitory nervous system plays a role in the pathogenesis of neuromuscular and neurological diseases: a novel hypothesis. F1000Res 2016; 5:1435. [PMID: 27547379 PMCID: PMC4984481 DOI: 10.12688/f1000research.8774.2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/12/2016] [Indexed: 11/20/2022] Open
Abstract
Based upon a thorough review of published clinical observations regarding the inhibitory system, I hypothesize that this system may play a key role in the pathogenesis of a variety of neuromuscular and neurological diseases. Specifically, excitatory overstimulation, which is commonly reported in neuromuscular and neurological diseases, may be a homeostatic response to inhibitory overstimulation. Involvement of the inhibitory system in disease pathogenesis is highly relevant, given that most approaches currently being developed for treating neuromuscular and neurological diseases focus on reducing excitatory activity rather than reducing inhibitory activity.
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Affiliation(s)
- Bert Tuk
- Leiden Academic Center for Drug Research (LACDR), Leiden University, Leiden, 2333 CC, Netherlands; Ry Pharma, Hofstraat 1, Willemstad, 4797 AC, Netherlands
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36
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Behavioural and psychological symptoms of dementia in Down syndrome: Early indicators of clinical Alzheimer's disease? Cortex 2015; 73:36-61. [DOI: 10.1016/j.cortex.2015.07.032] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 07/07/2015] [Accepted: 07/13/2015] [Indexed: 11/19/2022]
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37
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Nizetic D, Chen CL, Hong W, Koo EH. Inter-Dependent Mechanisms Behind Cognitive Dysfunction, Vascular Biology and Alzheimer's Dementia in Down Syndrome: Multi-Faceted Roles of APP. Front Behav Neurosci 2015; 9:299. [PMID: 26648852 PMCID: PMC4664698 DOI: 10.3389/fnbeh.2015.00299] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 10/27/2015] [Indexed: 01/05/2023] Open
Abstract
People with Down syndrome (DS) virtually all develop intellectual disability (ID) of varying degree of severity, and also have a high risk of early Alzheimer's disease (AD). ID prior to the onset of dementia, and its relationship to the onset of dementia in DS is a complex phenomenon influenced by many factors, and scarcely understood. Unraveling the causative factors and modulators of these processes remains a challenge, with potential to be informative for both ID and AD, for the development of early biomarkers and/or therapeutic approaches. We review the potential relative and inter-connected roles of the chromosome 21 gene for amyloid precursor protein (APP), in both pathological conditions. Rare non-DS people with duplication of APP (dupAPP) get familial early onset AD (FEOAD) with virtually 100% penetrance and prominent cerebrovascular pathology, but don't suffer from ID before dementia onset. All of these features appear to be radically different in DS. On the other hand, rare individuals with partial trisomy 21 (T21) (with APP, but not DS-critical region in trisomy) have been described having ID. Likewise, partial T21 DS (without APP trisomy) show a range of ID, but no AD pathology. We review the multi-faceted roles of APP that might affect cognitive functioning. Given the fact that both Aβ secretion and synaptic maturation/plasticity are dependent on neuronal activity, we explore how this conflicting inter-dependency might affect cognitive pathogenesis in a dynamic way in DS, throughout the lifespan of an individual.
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Affiliation(s)
- Dean Nizetic
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore Singapore ; The LonDownS Consortium, Wellcome Trust London, UK ; The Blizard Institute, Barts and The London School of Medicine, Queen Mary University of London London, UK
| | - Christopher L Chen
- Department of Psychological Medicine and Memory Aging and Cognition Centre, National University Health System, Singapore Singapore ; Department of Pharmacology, National University of Singapore, Singapore Singapore
| | - Wanjin Hong
- Agency for Science, Technology and Research (AStar), Institute of Molecular Cell Biology, Singapore Singapore
| | - Edward H Koo
- Departments of Medicine and Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore Singapore ; Department of Neurosciences, University of California, San Diego San Diego, CA, USA
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38
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Mucke HA. Drug Repurposing Patent Applications April–June 2015. Assay Drug Dev Technol 2015; 13:654-60. [DOI: 10.1089/adt.2015.29030.pq2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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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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40
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Johansson M, Agusti A, Llansola M, Montoliu C, Strömberg J, Malinina E, Ragagnin G, Doverskog M, Bäckström T, Felipo V. GR3027 antagonizes GABAA receptor-potentiating neurosteroids and restores spatial learning and motor coordination in rats with chronic hyperammonemia and hepatic encephalopathy. Am J Physiol Gastrointest Liver Physiol 2015; 309:G400-9. [PMID: 26138462 PMCID: PMC4556948 DOI: 10.1152/ajpgi.00073.2015] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 06/29/2015] [Indexed: 01/31/2023]
Abstract
Hepatic encephalopathy (HE) is one of the primary complications of liver cirrhosis. Current treatments for HE, mainly directed to reduction of ammonia levels, are not effective enough because they cannot completely eliminate hyperammonemia and inflammation, which induce the neurological alterations. Studies in animal models show that overactivation of GABAA receptors is involved in cognitive and motor impairment in HE and that reducing this activation restores these functions. We have developed a new compound, GR3027, that selectively antagonizes the enhanced activation of GABAA receptors by neurosteroids such as allopregnanolone and 3α,21-dihydroxy-5α-pregnan-20-one (THDOC). This work aimed to assess whether GR3027 improves motor incoordination, spatial learning, and circadian rhythms of activity in rats with HE. GR3027 was administered subcutaneously to two main models of HE: rats with chronic hyperammonemia due to ammonia feeding and rats with portacaval shunts (PCS). Motor coordination was assessed in beam walking and spatial learning and memory in the Morris water maze and the radial maze. Circadian rhythms of ambulatory and vertical activity were also assessed. In both hyperammonemic and PCS rats, GR3027 restores motor coordination, spatial memory in the Morris water maze, and spatial learning in the radial maze. GR3027 also partially restores circadian rhythms of ambulatory and vertical activity in PCS rats. GR3027 is a novel approach to treatment of HE that would normalize neurological functions altered because of enhanced GABAergic tone, affording more complete normalization of cognitive and motor function than current treatments for HE.
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Affiliation(s)
- Maja Johansson
- 1Umecrine Cognition AB, Solna, Sweden; ,2Umeå Neurosteroid Research Center, Department of Clinical Sciences, Umeå University, Umeå, Sweden;
| | | | | | | | - Jessica Strömberg
- 2Umeå Neurosteroid Research Center, Department of Clinical Sciences, Umeå University, Umeå, Sweden;
| | - Evgenya Malinina
- 2Umeå Neurosteroid Research Center, Department of Clinical Sciences, Umeå University, Umeå, Sweden;
| | - Gianna Ragagnin
- 2Umeå Neurosteroid Research Center, Department of Clinical Sciences, Umeå University, Umeå, Sweden;
| | | | - Torbjörn Bäckström
- 2Umeå Neurosteroid Research Center, Department of Clinical Sciences, Umeå University, Umeå, Sweden;
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41
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Stamenić TT, Joksimović S, Biawat P, Stanković T, Marković B, Cook JM, Savić MM. Negative modulation of α₅ GABAA receptors in rats may partially prevent memory impairment induced by MK-801, but not amphetamine- or MK-801-elicited hyperlocomotion. J Psychopharmacol 2015; 29:1013-24. [PMID: 26105958 PMCID: PMC4861997 DOI: 10.1177/0269881115590601] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Reportedly, negative modulation of α5 GABAA receptors may improve cognition in normal and pharmacologically-impaired animals, and such modulation has been proposed as an avenue for treatment of cognitive symptoms in schizophrenia. This study assessed the actions of PWZ-029, administered at doses (2, 5, and 10 mg/kg) at which it reached micromolar concentrations in brain tissue with estimated free concentrations adequate for selective modulation of α5 GABAA receptors, in three cognitive tasks in male Wistar rats acutely treated with the noncompetitive N-methyl-d-aspartate receptor antagonist, MK-801 (0.1 mg/kg), as well in tests of locomotor activity potentiated by MK-801 (0.2 mg/kg) or amphetamine (0.5 mg/kg). In a hormetic-like manner, only 5 mg/kg PWZ-029 reversed MK-801-induced deficits in novel object recognition test (visual recognition memory), whereas in the Morris water maze, the 2 mg/kg dose of PWZ-029 exerted partial beneficial effects on spatial learning impairment. PWZ-029 did not affect recognition memory deficits in social novelty discrimination procedure. Motor hyperactivity induced with MK-801 or amphetamine was not preventable by PWZ-029. Our results show that certain MK-801-induced memory deficits can be ameliorated by negative modulation of α5 GABAA receptors, and point to the need for further elucidation of their translational relevance to cognitive deterioration in schizophrenia.
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Affiliation(s)
| | - Srdjan Joksimović
- Department of Pharmacology, University of Belgrade, Belgrade, Serbia
| | - Poonam Biawat
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Tamara Stanković
- Department of Pharmacology, University of Belgrade, Belgrade, Serbia
| | - Bojan Marković
- Department of Pharmaceutical Chemistry, University of Belgrade, Belgrade, Serbia
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Miroslav M Savić
- Department of Pharmacology, University of Belgrade, Belgrade, Serbia
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Möhler H. The legacy of the benzodiazepine receptor: from flumazenil to enhancing cognition in Down syndrome and social interaction in autism. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2014; 72:1-36. [PMID: 25600365 DOI: 10.1016/bs.apha.2014.10.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The study of the psychopharmacology of benzodiazepines continues to provide new insights into diverse brain functions related to vigilance, anxiety, mood, epileptiform activity, schizophrenia, cognitive performance, and autism-related social behavior. In this endeavor, the discovery of the benzodiazepine receptor was a key event, as it supplied the primary benzodiazepine drug-target site, provided the molecular link to the allosteric modulation of GABAA receptors and, following the recognition of GABAA receptor subtypes, furnished the platform for future, more selective drug actions. This review has two parts. In a retrospective first part, it acknowledges the contributions to the field made by my collaborators over the years, initially at Hoffmann-La Roche in Basle and later, in academia, at the University and the ETH of Zurich. In the second part, the new frontier of GABA pharmacology, targeting GABAA receptor subtypes, is reviewed with special focus on nonsedative anxiolytics, antidepressants, analgesics, as well as enhancers of cognition in Down syndrome and attenuators of symptoms of autism spectrum disorders. It is encouraging that a clinical trial has been initiated with a partial inverse agonist acting on α5 GABAA receptors in an attempt to alleviate the cognitive deficits in Down syndrome.
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Affiliation(s)
- Hanns Möhler
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland; Department of Chemistry and Applied Biosciences, Federal Institute of Technology (ETH), Zurich, Switzerland.
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Lysenko LV, Kim J, Henry C, Tyrtyshnaia A, Kohnz RA, Madamba F, Simon GM, Kleschevnikova NE, Nomura DK, Ezekowitz R.AB, Kleschevnikov AM. Monoacylglycerol lipase inhibitor JZL184 improves behavior and neural properties in Ts65Dn mice, a model of down syndrome. PLoS One 2014; 9:e114521. [PMID: 25474204 PMCID: PMC4256450 DOI: 10.1371/journal.pone.0114521] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 11/10/2014] [Indexed: 12/13/2022] Open
Abstract
Genetic alterations or pharmacological treatments affecting endocannabinoid signaling have profound effects on synaptic and neuronal properties and, under certain conditions, may improve higher brain functions. Down syndrome (DS), a developmental disorder caused by triplication of chromosome 21, is characterized by deficient cognition and inevitable development of the Alzheimer disease (AD) type pathology during aging. Here we used JZL184, a selective inhibitor of monoacylglycerol lipase (MAGL), to examine the effects of chronic MAGL inhibition on the behavioral, biochemical, and synaptic properties of aged Ts65Dn mice, a genetic model of DS. In both Ts65Dn mice and their normosomic (2N) controls, JZL184-treatment increased brain levels of 2-arachidonoylglycerol (2-AG) and decreased levels of its metabolites such as arachidonic acid, prostaglandins PGD2, PGE2, PGFα, and PGJ2. Enhanced spontaneous locomotor activity of Ts65Dn mice was reduced by the JZL184-treatement to the levels observed in 2N animals. Deficient long-term memory was also improved, while short-term and working types of memory were unaffected. Furthermore, reduced hippocampal long-term potentiation (LTP) was increased in the JZL184-treated Ts65Dn mice to the levels observed in 2N mice. Interestingly, changes in synaptic plasticity and behavior were not observed in the JZL184-treated 2N mice suggesting that the treatment specifically attenuated the defects in the trisomic animals. The JZL184-treatment also reduced the levels of Aβ40 and Aβ42, but had no effect on the levels of full length APP and BACE1 in both Ts65Dn and 2N mice. These data show that chronic MAGL inhibition improves the behavior and brain functions in a DS model suggesting that pharmacological targeting of MAGL may be considered as a perspective new approach for improving cognition in DS.
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Affiliation(s)
- Larisa V. Lysenko
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Jeesun Kim
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Cassandra Henry
- Abide Therapeutics, Inc., San Diego, CA, United States of America
| | - Anna Tyrtyshnaia
- School of Biomedicine, Far Eastern Federal University, Sukhanova 8, Vladivostok, Russian Federation
| | - Rebecca A. Kohnz
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California, United States of America
| | - Francisco Madamba
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Gabriel M. Simon
- Abide Therapeutics, Inc., San Diego, CA, United States of America
| | - Natalia E. Kleschevnikova
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Daniel K. Nomura
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California, United States of America
| | | | - Alexander M. Kleschevnikov
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
- * E-mail:
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García-Cerro S, Martínez P, Vidal V, Corrales A, Flórez J, Vidal R, Rueda N, Arbonés ML, Martínez-Cué C. Overexpression of Dyrk1A is implicated in several cognitive, electrophysiological and neuromorphological alterations found in a mouse model of Down syndrome. PLoS One 2014; 9:e106572. [PMID: 25188425 PMCID: PMC4154723 DOI: 10.1371/journal.pone.0106572] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/30/2014] [Indexed: 01/09/2023] Open
Abstract
Down syndrome (DS) phenotypes result from the overexpression of several dosage-sensitive genes. The DYRK1A (dual-specificity tyrosine-(Y)-phosphorylation regulated kinase 1A) gene, which has been implicated in the behavioral and neuronal alterations that are characteristic of DS, plays a role in neuronal progenitor proliferation, neuronal differentiation and long-term potentiation (LTP) mechanisms that contribute to the cognitive deficits found in DS. The purpose of this study was to evaluate the effect of Dyrk1A overexpression on the behavioral and cognitive alterations in the Ts65Dn (TS) mouse model, which is the most commonly utilized mouse model of DS, as well as on several neuromorphological and electrophysiological properties proposed to underlie these deficits. In this study, we analyzed the phenotypic differences in the progeny obtained from crosses of TS females and heterozygous Dyrk1A (+/-) male mice. Our results revealed that normalization of the Dyrk1A copy number in TS mice improved working and reference memory based on the Morris water maze and contextual conditioning based on the fear conditioning test and rescued hippocampal LTP. Concomitant with these functional improvements, normalization of the Dyrk1A expression level in TS mice restored the proliferation and differentiation of hippocampal cells in the adult dentate gyrus (DG) and the density of GABAergic and glutamatergic synapse markers in the molecular layer of the hippocampus. However, normalization of the Dyrk1A gene dosage did not affect other structural (e.g., the density of mature hippocampal granule cells, the DG volume and the subgranular zone area) or behavioral (i.e., hyperactivity/attention) alterations found in the TS mouse. These results suggest that Dyrk1A overexpression is involved in some of the cognitive, electrophysiological and neuromorphological alterations, but not in the structural alterations found in DS, and suggest that pharmacological strategies targeting this gene may improve the treatment of DS-associated learning disabilities.
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Affiliation(s)
- Susana García-Cerro
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Paula Martínez
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Verónica Vidal
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Andrea Corrales
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Jesús Flórez
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Rebeca Vidal
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
- Institute of Biomedicine and Biotechnology (IBBITEC), (University of Cantabria- Consejo Superior de Investigaciones Científicas (CSIC) and Investigación, Desarrollo e Investigación Cantabria (IDICAN)), Santander, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Noemí Rueda
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - María L. Arbonés
- Barcelona Institute of Molecular Biology, Centro Superior de Investigaciones Científicas (CSIC) and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona, Spain
| | - Carmen Martínez-Cué
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
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