1
|
Albadrani HM, Chauhan P, Ashique S, Babu MA, Iqbal D, Almutary AG, Abomughaid MM, Kamal M, Paiva-Santos AC, Alsaweed M, Hamed M, Sachdeva P, Dewanjee S, Jha SK, Ojha S, Slama P, Jha NK. Mechanistic insights into the potential role of dietary polyphenols and their nanoformulation in the management of Alzheimer's disease. Biomed Pharmacother 2024; 174:116376. [PMID: 38508080 DOI: 10.1016/j.biopha.2024.116376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 01/19/2024] [Accepted: 02/28/2024] [Indexed: 03/22/2024] Open
Abstract
Alzheimer's disease (AD) is a very common neurodegenerative disorder associated with memory loss and a progressive decline in cognitive activity. The two major pathophysiological factors responsible for AD are amyloid plaques (comprising amyloid-beta aggregates) and neurofibrillary tangles (consisting of hyperphosphorylated tau protein). Polyphenols, a class of naturally occurring compounds, are immensely beneficial for the treatment or management of various disorders and illnesses. Naturally occurring sources of polyphenols include plants and plant-based foods, such as fruits, herbs, tea, vegetables, coffee, red wine, and dark chocolate. Polyphenols have unique properties, such as being the major source of anti-oxidants and possessing anti-aging and anti-cancerous properties. Currently, dietary polyphenols have become a potential therapeutic approach for the management of AD, depending on various research findings. Dietary polyphenols can be an effective strategy to tackle multifactorial events that occur with AD. For instance, naturally occurring polyphenols have been reported to exhibit neuroprotection by modulating the Aβ biogenesis pathway in AD. Many nanoformulations have been established to enhance the bioavailability of polyphenols, with nanonization being the most promising. This review comprehensively provides mechanistic insights into the neuroprotective potential of dietary polyphenols in treating AD. It also reviews the usability of dietary polyphenol as nanoformulation for AD treatment.
Collapse
Affiliation(s)
- Hind Muteb Albadrani
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Imam Abdulrahman Bin Faisal University, Dammam, Eastern Province 34212, Saudi Arabia
| | - Payal Chauhan
- Department of Pharmaceutical Sciences, Maharshi Dayanad University, Rohtak, Haryana 124001, India
| | - Sumel Ashique
- Department of Pharmaceutical Sciences, Bengal College of Pharmaceutical Sciences & Research, Durgapur 713212, West Bengal, India
| | - M Arockia Babu
- Institute of Pharmaceutical Research, GLA University, Mathura, India
| | - Danish Iqbal
- Department of Health Information Management, College of Applied Medical Sciences, Buraydah Private Colleges, Buraydah 51418, Saudi Arabia
| | - Abdulmajeed G Almutary
- Department of Biomedical Sciences, College of Health Sciences, Abu Dhabi University, Abu Dhabi, United Arab Emirates
| | - Mosleh Mohammad Abomughaid
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, University of Bisha, Bisha 61922, Saudi Arabia
| | - Mehnaz Kamal
- Department of Pharmaceutical Chemistry, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia
| | - Ana Cláudia Paiva-Santos
- Department of Pharmaceutical Technology, Faculty of Pharmacy of the University of Coimbra, University of Coimbra, Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy of the University of Coimbra, University of Coimbra, Coimbra, Portugal
| | - Mohammed Alsaweed
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Al-Majmaah 11952, Saudi Arabia.
| | - Munerah Hamed
- Department of Pathology, Faculty of Medicine, Umm Al-Qura University, Makkah 21955, Saudi Arabia
| | | | - Saikat Dewanjee
- Advanced Pharmacognosy Research Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032, India
| | - Saurabh Kumar Jha
- Department of Zoology, Kalindi College, University of Delhi, 110008, India
| | - Shreesh Ojha
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 15551, Al Ain, United Arab Emirates
| | - Petr Slama
- Department of Animal Morphology, Physiology and Genetics, Faculty of AgriSciences, Mendel University in Brno, Brno, Czech Republic.
| | - Niraj Kumar Jha
- Centre for Global Health Research, Saveetha Medical College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India; Centre of Research Impact and Outcome, Chitkara University, Rajpura- 140401, Punjab, India.; School of Bioengineering & Biosciences, Lovely Professional University, Phagwara 144411, India; Department of Biotechnology, School of Applied & Life Sciences (SALS), Uttaranchal University, Dehradun, India.
| |
Collapse
|
2
|
Meanwell NA. The pyridazine heterocycle in molecular recognition and drug discovery. Med Chem Res 2023; 32:1-69. [PMID: 37362319 PMCID: PMC10015555 DOI: 10.1007/s00044-023-03035-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 02/06/2023] [Indexed: 03/17/2023]
Abstract
The pyridazine ring is endowed with unique physicochemical properties, characterized by weak basicity, a high dipole moment that subtends π-π stacking interactions and robust, dual hydrogen-bonding capacity that can be of importance in drug-target interactions. These properties contribute to unique applications in molecular recognition while the inherent polarity, low cytochrome P450 inhibitory effects and potential to reduce interaction of a molecule with the cardiac hERG potassium channel add additional value in drug discovery and development. The recent approvals of the gonadotropin-releasing hormone receptor antagonist relugolix (24) and the allosteric tyrosine kinase 2 inhibitor deucravacitinib (25) represent the first examples of FDA-approved drugs that incorporate a pyridazine ring. In this review, the properties of the pyridazine ring are summarized in comparison to the other azines and its potential in drug discovery is illustrated through vignettes that explore applications that take advantage of the inherent physicochemical properties as an approach to solving challenges associated with candidate optimization. Graphical Abstract
Collapse
|
3
|
Pharmacological Signature and Target Specificity of Inhibitory Circuits Formed by Martinotti Cells in the Mouse Barrel Cortex. J Neurosci 2023; 43:14-27. [PMID: 36384682 PMCID: PMC9838699 DOI: 10.1523/jneurosci.1661-21.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/13/2022] [Accepted: 10/26/2022] [Indexed: 11/18/2022] Open
Abstract
In the neocortex, fast synaptic inhibition orchestrates both spontaneous and sensory-evoked activity. GABAergic interneurons (INs) inhibit pyramidal neurons (PNs) directly, modulating their output activity and thus contributing to balance cortical networks. Moreover, several IN subtypes also inhibit other INs, forming specific disinhibitory circuits, which play crucial roles in several cognitive functions. Here, we studied a subpopulation of somatostatin-positive INs, the Martinotti cells (MCs) in layer 2/3 of the mouse barrel cortex (both sexes). MCs inhibit the distal portion of PN apical dendrites, thus controlling dendrite electrogenesis and synaptic integration. Yet, it is poorly understood whether MCs inhibit other elements of the cortical circuits, and the connectivity properties with non-PN targets are unknown. We found that MCs have a strong preference for PN dendrites, but they also considerably connect with parvalbumin-positive, vasoactive intestinal peptide-expressing, and layer 1 (L1) INs. Remarkably, GABAergic synapses from MCs exhibited clear cell type-specific short-term plasticity. Moreover, whereas the biophysical properties of MC-PN synapses were consistent with distal dendritic inhibition, MC-IN synapses exhibited characteristics of fast perisomatic inhibition. Finally, MC-PN connections used α5-containing GABAA receptors (GABAARs), but this subunit was not expressed by the other INs targeted by MCs. We reveal a specialized connectivity blueprint of MCs within different elements of superficial cortical layers. In addition, our results identify α5-GABAARs as the molecular fingerprint of MC-PN dendritic inhibition. This is of critical importance, given the role of α5-GABAARs in cognitive performance and their involvement in several brain diseases.SIGNIFICANCE STATEMENT Martinotti cells (MCs) are a prominent, broad subclass of somatostatin-expressing GABAergic interneurons, specialized in controlling distal dendrites of pyramidal neurons (PNs) and taking part in several cognitive functions. Here we characterize the connectivity pattern of MCs with other interneurons in the superficial layers (L1 and L2/3) of the mouse barrel cortex. We found that the connectivity pattern of MCs with PNs as well as parvalbumin, vasoactive intestinal peptide, and L1 interneurons exhibit target-specific plasticity and biophysical properties. The specificity of α5-GABAARs at MC-PN synapses and the lack or functional expression of this subunit by other cell types define the molecular identity of MC-PN connections and the exclusive involvement of this inhibitory circuits in α5-dependent cognitive tasks.
Collapse
|
4
|
Wang Z, Choi K. Pharmacological modulation of chloride channels as a therapeutic strategy for neurological disorders. Front Physiol 2023; 14:1122444. [PMID: 36935741 PMCID: PMC10017882 DOI: 10.3389/fphys.2023.1122444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 02/09/2023] [Indexed: 03/06/2023] Open
Abstract
Chloride homeostasis is critical in the physiological functions of the central nervous system (CNS). Its concentration is precisely regulated by multiple ion-transporting proteins such as chloride channels and transporters that are widely distributed in the brain cells, including neurons and glia. Unlike ion transporters, chloride channels provide rapid responses to efficiently regulate ion flux. Some of chloride channels are also permeable to selected organic anions such as glutamate and γ-aminobutyric acid, suggesting neuroexcitatory and neuroinhibitory functions while gating. Dysregulated chloride channels are implicated in neurological disorders, e.g., ischemia and neuroinflammation. Modulation of chloride homeostasis through chloride channels has been suggested as a potential therapeutic approach for neurological disorders. The drug design for CNS diseases is challenging because it requires the therapeutics to traverse the blood-brain-barrier. Small molecules are a well-established modality with better cell permeability due to their lower molecular weight and flexibility for structure optimization compared to biologics. In this article, we describe the important roles of chloride homeostasis in each type of brain cells and introduce selected chloride channels identified in the CNS. We then discuss the contribution of their dysregulations towards the pathogenesis of neurological disorders, emphasizing the potential of targeting chloride channels as a therapeutic strategy for CNS disease treatment. Along with this literature survey, we summarize the small molecules that modulate chloride channels and propose the potential strategy of optimizing existing drugs to brain-penetrants to support future CNS drug discovery.
Collapse
|
5
|
Distinct sex-dependent behavioral responses induced by two positive allosteric modulators of alpha 5 subunit-containing GABAA receptors. Behav Brain Res 2022; 428:113832. [DOI: 10.1016/j.bbr.2022.113832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 02/24/2022] [Accepted: 03/03/2022] [Indexed: 11/18/2022]
|
6
|
Ghit A, Assal D, Al-Shami AS, Hussein DEE. GABA A receptors: structure, function, pharmacology, and related disorders. J Genet Eng Biotechnol 2021; 19:123. [PMID: 34417930 PMCID: PMC8380214 DOI: 10.1186/s43141-021-00224-0] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 08/08/2021] [Indexed: 02/03/2023]
Abstract
Background γ-Aminobutyric acid sub-type A receptors (GABAARs) are the most prominent inhibitory neurotransmitter receptors in the CNS. They are a family of ligand-gated ion channel with significant physiological and therapeutic implications. Main body GABAARs are heteropentamers formed from a selection of 19 subunits: six α (alpha1-6), three β (beta1-3), three γ (gamma1-3), three ρ (rho1-3), and one each of the δ (delta), ε (epsilon), π (pi), and θ (theta) which result in the production of a considerable number of receptor isoforms. Each isoform exhibits distinct pharmacological and physiological properties. However, the majority of GABAARs are composed of two α subunits, two β subunits, and one γ subunit arranged as γ2β2α1β2α1 counterclockwise around the center. The mature receptor has a central chloride ion channel gated by GABA neurotransmitter and modulated by a variety of different drugs. Changes in GABA synthesis or release may have a significant effect on normal brain function. Furthermore, The molecular interactions and pharmacological effects caused by drugs are extremely complex. This is due to the structural heterogeneity of the receptors, and the existence of multiple allosteric binding sites as well as a wide range of ligands that can bind to them. Notably, dysfunction of the GABAergic system contributes to the development of several diseases. Therefore, understanding the relationship between GABAA receptor deficits and CNS disorders thus has a significant impact on the discovery of disease pathogenesis and drug development. Conclusion To date, few reviews have discussed GABAA receptors in detail. Accordingly, this review aims to summarize the current understanding of the structural, physiological, and pharmacological properties of GABAARs, as well as shedding light on the most common associated disorders.
Collapse
Affiliation(s)
- Amr Ghit
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy. .,Department of Biotechnology, Institute of Graduate Studies and Research (IGSR), Alexandria University, Alexandria, Egypt.
| | - Dina Assal
- Department of Biotechnology, American University in Cairo (AUC), Cairo, Egypt
| | - Ahmed S Al-Shami
- Department of Biotechnology, Institute of Graduate Studies and Research (IGSR), Alexandria University, Alexandria, Egypt.,Department of Zoology, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Diaa Eldin E Hussein
- Animal Health Research Institute (AHRI), Agricultural Research Center (ARC), Port of Alexandria, Alexandria, Egypt
| |
Collapse
|
7
|
McGinnity CJ, Riaño Barros DA, Hinz R, Myers JF, Yaakub SN, Thyssen C, Heckemann RA, de Tisi J, Duncan JS, Sander JW, Lingford-Hughes A, Koepp MJ, Hammers A. Αlpha 5 subunit-containing GABA A receptors in temporal lobe epilepsy with normal MRI. Brain Commun 2021; 3:fcaa190. [PMID: 33501420 PMCID: PMC7811756 DOI: 10.1093/braincomms/fcaa190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 09/06/2020] [Accepted: 09/24/2020] [Indexed: 01/08/2023] Open
Abstract
GABAA receptors containing the α5 subunit mediate tonic inhibition and are widely expressed in the limbic system. In animals, activation of α5-containing receptors impairs hippocampus-dependent memory. Temporal lobe epilepsy is associated with memory impairments related to neuron loss and other changes. The less selective PET ligand [11C]flumazenil has revealed reductions in GABAA receptors. The hypothesis that α5 subunit receptor alterations are present in temporal lobe epilepsy and could contribute to impaired memory is untested. We compared α5 subunit availability between individuals with temporal lobe epilepsy and normal structural MRI ('MRI-negative') and healthy controls, and interrogated the relationship between α5 subunit availability and episodic memory performance, in a cross-sectional study. Twenty-three healthy male controls (median ± interquartile age 49 ± 13 years) and 11 individuals with MRI-negative temporal lobe epilepsy (seven males; 40 ± 8) had a 90-min PET scan after bolus injection of [11C]Ro15-4513, with arterial blood sampling and metabolite correction. All those with epilepsy and six controls completed the Adult Memory and Information Processing Battery on the scanning day. 'Bandpass' exponential spectral analyses were used to calculate volumes of distribution separately for the fast component [V F; dominated by signal from α1 (α2, α3)-containing receptors] and the slow component (V S; dominated by signal from α5-containing receptors). We made voxel-by-voxel comparisons between: the epilepsy and control groups; each individual case versus the controls. We obtained parametric maps of V F and V S measures from a single bolus injection of [11C]Ro15-4513. The epilepsy group had higher V S in anterior medial and lateral aspects of the temporal lobes, the anterior cingulate gyri, the presumed area tempestas (piriform cortex) and the insulae, in addition to increases of ∼24% and ∼26% in the ipsilateral and contralateral hippocampal areas (P < 0.004). This was associated with reduced V F:V S ratios within the same areas (P < 0.009). Comparisons of V S for each individual with epilepsy versus controls did not consistently lateralize the epileptogenic lobe. Memory scores were significantly lower in the epilepsy group than in controls (mean ± standard deviation -0.4 ± 1.0 versus 0.7 ± 0.3; P = 0.02). In individuals with epilepsy, hippocampal V S did not correlate with memory performance on the Adult Memory and Information Processing Battery. They had reduced V F in the hippocampal area, which was significant ipsilaterally (P = 0.03), as expected from [11C]flumazenil studies. We found increased tonic inhibitory neurotransmission in our cohort of MRI-negative temporal lobe epilepsy who also had co-morbid memory impairments. Our findings are consistent with a subunit shift from α1/2/3 to α5 in MRI-negative temporal lobe epilepsy.
Collapse
Affiliation(s)
- Colm J McGinnity
- Centre for Neuroscience, Department of Medicine, Imperial College London, London W12 0NN, UK
- MRC Clinical Sciences Centre, Hammersmith Hospital, London W12 0NN, UK
- King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Daniela A Riaño Barros
- Centre for Neuroscience, Department of Medicine, Imperial College London, London W12 0NN, UK
- MRC Clinical Sciences Centre, Hammersmith Hospital, London W12 0NN, UK
| | - Rainer Hinz
- Wolfson Molecular Imaging Centre, University of Manchester, Manchester M20 3LJ, UK
| | - James F Myers
- Centre for Neuroscience, Department of Medicine, Imperial College London, London W12 0NN, UK
| | - Siti N Yaakub
- King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Charlotte Thyssen
- Medical Image and Signal Processing (MEDISIP), Department of Electronics and Information Systems, Faculty of Engineering and Architecture, Ghent University, 9000 Ghent, Belgium
| | - Rolf A Heckemann
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, 413 45 Gothenburg, Sweden
| | - Jane de Tisi
- NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK, and Chalfont Centre for Epilepsy, Chalfont St Peter SL9 0RJ, UK
| | - John S Duncan
- NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK, and Chalfont Centre for Epilepsy, Chalfont St Peter SL9 0RJ, UK
| | - Josemir W Sander
- NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK, and Chalfont Centre for Epilepsy, Chalfont St Peter SL9 0RJ, UK
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede 2103SW, The Netherlands
| | - Anne Lingford-Hughes
- Neuropsychopharmacology Unit, Centre for Psychiatry, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London W12 0NN, UK
| | - Matthias J Koepp
- NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK, and Chalfont Centre for Epilepsy, Chalfont St Peter SL9 0RJ, UK
| | - Alexander Hammers
- Centre for Neuroscience, Department of Medicine, Imperial College London, London W12 0NN, UK
- MRC Clinical Sciences Centre, Hammersmith Hospital, London W12 0NN, UK
- King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EH, UK
- Neurodis Foundation, CERMEP, Imagerie du Vivant, 69003 Lyon, France
| |
Collapse
|
8
|
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.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Afia B Ali
- UCL School of Pharmacy, London, United Kingdom
| |
Collapse
|
9
|
Lewis A, Beresford A, Chambers MS, Clark G, Hartley DC, Hirst KL, Higashino M, Kawahadara S, Nakanishi M, Saito T, Imagawa A, Habashita H, Maidment S, Macleod AM, Owens AP, Rae A, Rouse C, Wishart G. Discovery of ONO-8590580: A novel, potent and selective GABA A α 5 negative allosteric modulator for the treatment of cognitive disorders. Bioorg Med Chem Lett 2020; 30:127536. [PMID: 32898695 DOI: 10.1016/j.bmcl.2020.127536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 10/23/2022]
Abstract
The identification and SAR development of a series of negative allosteric modulators of the GABAA α5 receptor is described. This novel series of compounds was optimised to provide analogues with high GABAA α5 binding affinity, high α5 negative allosteric modulatory activity, good functional subtype selectivity and low microsomal turnover, culminating in identification of ONO-8590580.
Collapse
Affiliation(s)
- A Lewis
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - A Beresford
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - M S Chambers
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - G Clark
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - D C Hartley
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - K L Hirst
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - M Higashino
- Ono Pharmaceutical Co. Ltd., Minase Research Institute, Shimamoto-cho, Mishima-gun, Osaka 618-8585, Japan
| | - S Kawahadara
- Ono Pharmaceutical Co. Ltd., Minase Research Institute, Shimamoto-cho, Mishima-gun, Osaka 618-8585, Japan
| | - M Nakanishi
- Ono Pharmaceutical Co. Ltd., Minase Research Institute, Shimamoto-cho, Mishima-gun, Osaka 618-8585, Japan
| | - T Saito
- Ono Pharmaceutical Co. Ltd., Minase Research Institute, Shimamoto-cho, Mishima-gun, Osaka 618-8585, Japan
| | - A Imagawa
- Ono Pharmaceutical Co. Ltd., Minase Research Institute, Shimamoto-cho, Mishima-gun, Osaka 618-8585, Japan
| | - H Habashita
- Ono Pharmaceutical Co. Ltd., Minase Research Institute, Shimamoto-cho, Mishima-gun, Osaka 618-8585, Japan
| | - S Maidment
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - A M Macleod
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - A P Owens
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - A Rae
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom.
| | - C Rouse
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| | - G Wishart
- Charles River Discovery Research Services, Chesterford Research Park, Little Chesterford, Essex CB10 1XL, United Kingdom
| |
Collapse
|
10
|
Zorrilla de San Martin J, Donato C, Peixoto J, Aguirre A, Choudhary V, De Stasi AM, Lourenço J, Potier MC, Bacci A. Alterations of specific cortical GABAergic circuits underlie abnormal network activity in a mouse model of Down syndrome. eLife 2020; 9:58731. [PMID: 32783810 PMCID: PMC7481006 DOI: 10.7554/elife.58731] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 08/11/2020] [Indexed: 12/21/2022] Open
Abstract
Down syndrome (DS) results in various degrees of cognitive deficits. In DS mouse models, recovery of behavioral and neurophysiological deficits using GABAAR antagonists led to hypothesize an excessive activity of inhibitory circuits in this condition. Nonetheless, whether over-inhibition is present in DS and whether this is due to specific alterations of distinct GABAergic circuits is unknown. In the prefrontal cortex of Ts65Dn mice (a well-established DS model), we found that the dendritic synaptic inhibitory loop formed by somatostatin-positive Martinotti cells (MCs) and pyramidal neurons (PNs) was strongly enhanced, with no alteration in their excitability. Conversely, perisomatic inhibition from parvalbumin-positive (PV) interneurons was unaltered, but PV cells of DS mice lost their classical fast-spiking phenotype and exhibited increased excitability. These microcircuit alterations resulted in reduced pyramidal-neuron firing and increased phase locking to cognitive-relevant network oscillations in vivo. These results define important synaptic and circuit mechanisms underlying cognitive dysfunctions in DS. Down syndrome is a genetic disorder caused by the presence of a third copy of chromosome 21. Affected individuals show delayed growth, characteristic facial features, altered brain development; with mild to severe intellectual disability. The exact mechanisms underlying the intellectual disability in Down syndrome are unclear, although studies in mice have provided clues. Drugs that reduce the inhibitory activity in the brain improve cognition in a mouse model of Down syndrome. This suggests that excessive inhibitory activity may contribute to the cognitive impairments. Many different neural circuits generate inhibitory activity in the brain. These circuits contain cells called interneurons. Sub-types of interneurons act via different mechanisms to reduce the activity of neurons. Identifying the interneurons that are affected in Down syndrome would thus improve our understanding of the brain basis of the disorder. Zorrilla de San Martin et al. compared mice with Down syndrome to unaffected control mice. The results revealed an increased activity in two types of inhibitory brain circuits in Down syndrome. The first contains interneurons called Martinotti cells. These help the brain to combine inputs from different sources. The second contains interneurons called parvalbumin-positive basket cells. These help different areas of the brain to synchronize their activity, which in turn makes it easier for those areas to exchange information. By mapping the changes in inhibitory circuits in Down syndrome, Zorrilla de San Martin et al. have provided new insights into the biological basis of the disorder. Future studies should examine whether targeting specific circuits with pharmacological treatments could ultimately help reduce the associated impairments.
Collapse
Affiliation(s)
| | - Cristina Donato
- Institut du Cerveau (ICM), CNRS UMR 7225 - Inserm U1127, Sorbonne Université, Paris, France
| | - Jérémy Peixoto
- Institut du Cerveau (ICM), CNRS UMR 7225 - Inserm U1127, Sorbonne Université, Paris, France
| | - Andrea Aguirre
- Institut du Cerveau (ICM), CNRS UMR 7225 - Inserm U1127, Sorbonne Université, Paris, France
| | - Vikash Choudhary
- Institut du Cerveau (ICM), CNRS UMR 7225 - Inserm U1127, Sorbonne Université, Paris, France
| | | | - Joana Lourenço
- Institut du Cerveau (ICM), CNRS UMR 7225 - Inserm U1127, Sorbonne Université, Paris, France
| | - Marie-Claude Potier
- Institut du Cerveau (ICM), CNRS UMR 7225 - Inserm U1127, Sorbonne Université, Paris, France
| | - Alberto Bacci
- Institut du Cerveau (ICM), CNRS UMR 7225 - Inserm U1127, Sorbonne Université, Paris, France
| |
Collapse
|
11
|
Nguyen AQ, Koeppen J, Woodruff S, Mina K, Figueroa Z, Ethell IM. Astrocytic Ephrin-B1 Controls Synapse Formation in the Hippocampus During Learning and Memory. Front Synaptic Neurosci 2020; 12:10. [PMID: 32256333 PMCID: PMC7092624 DOI: 10.3389/fnsyn.2020.00010] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 02/24/2020] [Indexed: 01/20/2023] Open
Abstract
Astrocytes play a fundamental role in synapse formation, pruning, and plasticity, which are associated with learning and memory. However, the role of astrocytes in learning and memory is still largely unknown. Our previous study showed that astrocyte-specific ephrin-B1 knock-out (KO) enhanced but ephrin-B1 overexpression (OE) in hippocampal astrocytes impaired contextual memory recall following fear conditioning. The goal of this study was to understand the mechanism by which astrocytic ephrin-B1 influences learning; specifically, learning-induced remodeling of synapses and dendritic spines in CA1 hippocampus using fear-conditioning paradigm. While we found a higher dendritic spine density and clustering on c-Fos-positive (+) neurons activated during contextual memory recall in both wild-type (WT) and KO mice, overall spine density and mEPSC amplitude were increased in CA1 neurons of KO compared to WT. In contrast, ephrin-B1 OE in hippocampal astrocytes impaired dendritic spine formation and clustering, specifically on c-Fos(+) neurons, coinciding with an overall decrease in vGlut1/PSD95 co-localization. Although astrocytic ephrin-B1 influenced learning-induced spine formation, the changes in astrocytic ephrin-B1 levels did not affect spine enlargement as no genotype differences in spine volume were observed between trained WT, KO, and OE groups. Our results suggest that a reduced formation of new spines rather than spine maturation in activated CA1 hippocampal neurons is most likely responsible for impaired contextual learning in OE mice due to abundantly high ephrin-B1 levels in astrocytes. The ability of astrocytic ephrin-B1 to negatively influence new spine formation during learning can potentially regulate new synapse formation at specific dendritic domains and underlie memory encoding.
Collapse
Affiliation(s)
- Amanda Q. Nguyen
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States
| | - Jordan Koeppen
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
- Cell, Molecular, and Developmental Biology Graduate Program, University of California, Riverside, Riverside, CA, United States
| | - Simone Woodruff
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
| | - Karen Mina
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
| | - Zoe Figueroa
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
| | - Iryna M. Ethell
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States
- Cell, Molecular, and Developmental Biology Graduate Program, University of California, Riverside, Riverside, CA, United States
| |
Collapse
|
12
|
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.
Collapse
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
| |
Collapse
|
13
|
Pokhodylo NT, Tupychak MA, Shyyka OY, Obushak MD. Some Aspects of the Azide-Alkyne 1,3-Dipolar Cycloaddition Reaction. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2019. [DOI: 10.1134/s1070428019090082] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
14
|
Dhakal S, Kushairi N, Phan CW, Adhikari B, Sabaratnam V, Macreadie I. Dietary Polyphenols: A Multifactorial Strategy to Target Alzheimer's Disease. Int J Mol Sci 2019; 20:E5090. [PMID: 31615073 PMCID: PMC6834216 DOI: 10.3390/ijms20205090] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/11/2019] [Accepted: 10/11/2019] [Indexed: 02/06/2023] Open
Abstract
Ageing is an inevitable fundamental process for people and is their greatest risk factor for neurodegenerative disease. The ageing processes bring changes in cells that can drive the organisms to experience loss of nutrient sensing, disrupted cellular functions, increased oxidative stress, loss of cellular homeostasis, genomic instability, accumulation of misfolded protein, impaired cellular defenses and telomere shortening. Perturbation of these vital cellular processes in neuronal cells can lead to life threatening neurological disorders like Alzheimer's Disease, Parkinson's Disease, Huntington's Disease, Lewy body dementia, etc. Alzheimer's Disease is the most frequent cause of deaths in the elderly population. Various therapeutic molecules have been designed to overcome the social, economic and health care burden caused by Alzheimer's Disease. Almost all the chemical compounds in clinical practice have been found to treat symptoms only limiting them to palliative care. The reason behind such imperfect drugs may result from the inefficiencies of the current drugs to target the cause of the disease. Here, we review the potential role of antioxidant polyphenolic compounds that could possibly be the most effective preventative strategy against Alzheimer's Disease.
Collapse
Affiliation(s)
- Sudip Dhakal
- School of Science, RMIT University, Bundoora, Victoria 3083, Australia.
| | - Naufal Kushairi
- Mushroom Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia.
- Department of Anatomy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Chia Wei Phan
- Mushroom Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia.
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Benu Adhikari
- School of Science, RMIT University, Bundoora, Victoria 3083, Australia.
| | - Vikineswary Sabaratnam
- Mushroom Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia.
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Ian Macreadie
- School of Science, RMIT University, Bundoora, Victoria 3083, Australia.
| |
Collapse
|
15
|
Solomon VR, Tallapragada VJ, Chebib M, Johnston G, Hanrahan JR. GABA allosteric modulators: An overview of recent developments in non-benzodiazepine modulators. Eur J Med Chem 2019; 171:434-461. [DOI: 10.1016/j.ejmech.2019.03.043] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 02/17/2019] [Accepted: 03/17/2019] [Indexed: 01/13/2023]
|
16
|
Sharma P, Srivastava P, Seth A, Tripathi PN, Banerjee AG, Shrivastava SK. Comprehensive review of mechanisms of pathogenesis involved in Alzheimer's disease and potential therapeutic strategies. Prog Neurobiol 2018; 174:53-89. [PMID: 30599179 DOI: 10.1016/j.pneurobio.2018.12.006] [Citation(s) in RCA: 196] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 12/04/2018] [Accepted: 12/28/2018] [Indexed: 12/14/2022]
Abstract
AD is a progressive neurodegenerative disorder and a leading cause of dementia in an aging population worldwide. The enormous challenge which AD possesses to global healthcare makes it as urgent as ever for the researchers to develop innovative treatment strategies to fight this disease. An in-depth analysis of the extensive available data associated with the AD is needed for a more comprehensive understanding of underlying molecular mechanisms and pathophysiological pathways associated with the onset and progression of the AD. The currently understood pathological and biochemical manifestations include cholinergic, Aβ, tau, excitotoxicity, oxidative stress, ApoE, CREB signaling pathways, insulin resistance, etc. However, these hypotheses have been criticized with several conflicting reports for their involvement in the disease progression. Several issues need to be addressed such as benefits to cost ratio with cholinesterase therapy, the dilemma of AChE selectivity over BChE, BBB permeability of peptidic BACE-1 inhibitors, hurdles related to the implementation of vaccination and immunization therapy, and clinical failure of candidates related to newly available targets. The present review provides an insight to the different molecular mechanisms involved in the development and progression of the AD and potential therapeutic strategies, enlightening perceptions into structural information of conventional and novel targets along with the successful applications of computational approaches for the design of target-specific inhibitors.
Collapse
Affiliation(s)
- Piyoosh Sharma
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Pavan Srivastava
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Ankit Seth
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Prabhash Nath Tripathi
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Anupam G Banerjee
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Sushant K Shrivastava
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India.
| |
Collapse
|
17
|
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]
|
18
|
Chandler CM, Overton JS, Rüedi-Bettschen D, Platt DM. GABA A Receptor Subtype Mechanisms and the Abuse-Related Effects of Ethanol: Genetic and Pharmacological Evidence. Handb Exp Pharmacol 2018; 248:3-27. [PMID: 29204713 DOI: 10.1007/164_2017_80] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ethanol's reinforcing and subjective effects, as well as its ability to induce relapse, are powerful factors contributing to its widespread use and abuse. A significant mediator of these behavioral effects is the GABAA receptor system. GABAA receptors are the target for γ-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the CNS. Structurally, they are pentameric, transmembrane chloride ion channels comprised of subunits from at least eight different families of distinct proteins. The contribution of different GABAA subunits to ethanol's diverse abuse-related effects is not clear and remains an area of research focus. This chapter details the clinical and preclinical findings supporting roles for different α, β, γ, and δ subunit-containing GABAA receptors in ethanol's reinforcing, subjective/discriminative stimulus, and relapse-inducing effects. The reinforcing properties of ethanol have been studied the most systematically, and convergent preclinical evidence suggests a key role for the α5 subunit in those effects. Regarding ethanol's subjective/discriminative stimulus effects, clinical and genetic findings support a primary role for the α2 subunit, whereas preclinical evidence implicates the α5 subunit. At present, too few studies investigating ethanol relapse exist to make any solid conclusions regarding the role of specific GABAA subunits in this abuse-related effect.
Collapse
Affiliation(s)
- Cassie M Chandler
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS, USA
| | - John S Overton
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA
| | - Daniela Rüedi-Bettschen
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA
| | - Donna M Platt
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS, USA.
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA.
| |
Collapse
|
19
|
Chen X, Keramidas A, Lynch JW. Physiological and pharmacological properties of inhibitory postsynaptic currents mediated by α5β1γ2, α5β2γ2 and α5β3γ2 GABA A receptors. Neuropharmacology 2017; 125:243-253. [PMID: 28757051 DOI: 10.1016/j.neuropharm.2017.07.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/18/2017] [Accepted: 07/26/2017] [Indexed: 02/07/2023]
Abstract
α5-containing GABAARs are potential therapeutic targets for clinical conditions including age-related dementia, stroke, schizophrenia, Down syndrome, anaesthetic-induced amnesia, anxiety and pain. α5-containing GABAARs are expressed in layer 5 cortical neurons and hippocampal pyramidal neurons where they mediate both tonic currents and slow inhibitory postsynaptic currents (IPSCs). A range of drugs has been developed to specifically modulate these receptors. The main α5-containing GABAARs that are likely to exist in vivo are the α5β1γ2, α5β2γ2 and α5β3γ2 isoforms. We currently have few clues as to how these isoforms are distributed between synaptic and extrasynaptic compartments or their relative roles in controlling neuronal excitability. Accordingly, the aim of this study was to define the basic biophysical and pharmacological properties of IPSCs mediated by the three isoforms in a hippocampal neuron-HEK293 cell co-culture assay. The IPSC decay time constants were slow (α5β1γ2L: 45 ms; α5β1γ2L: 80 ms; α5β3γ2L: 184 ms) and were largely dominated by the intrinsic channel deactivation rates. By comparing IPSC rise times, we inferred that α5β1γ2L GABAARs are located postsynaptically whereas the other two are predominantly perisynaptic. α5β3γ2L GABAARs alone mediated tonic currents. We quantified the effects of four α5-specific inverse agonists (TB-21007, MRK-016, α5IA and L-655708) on IPSCs mediated by the three isoforms. All compounds selectively inhibited IPSC amplitudes and accelerated IPSC decay rates, albeit with distinct isoform specificities. MRK-016 also significantly accelerated IPSC rise times. These results provide a reference for future studies seeking to identify and characterize the properties of IPSCs mediated by α5-containing GABAAR isoforms in neurons.
Collapse
Affiliation(s)
- Xiumin Chen
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Angelo Keramidas
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Joseph W Lynch
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
| |
Collapse
|
20
|
McGinnity CJ, Riaño Barros DA, Rosso L, Veronese M, Rizzo G, Bertoldo A, Hinz R, Turkheimer FE, Koepp MJ, Hammers A. Test-retest reproducibility of quantitative binding measures of [ 11C]Ro15-4513, a PET ligand for GABA A receptors containing alpha5 subunits. Neuroimage 2017; 152:270-282. [PMID: 28292717 PMCID: PMC5440177 DOI: 10.1016/j.neuroimage.2016.12.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 11/20/2016] [Accepted: 12/14/2016] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION Alteration of γ-aminobutyric acid "A" (GABAA) receptor-mediated neurotransmission has been associated with various neurological and psychiatric disorders. [11C]Ro15-4513 is a PET ligand with high affinity for α5-subunit-containing GABAA receptors, which are highly expressed in limbic regions of the human brain (Sur et al., 1998). We quantified the test-retest reproducibility of measures of [11C]Ro15-4513 binding derived from six different quantification methods (12 variants). METHODS Five healthy males (median age 40 years, range 38-49 years) had a 90-min PET scan on two occasions (median interval 12 days, range 11-30 days), after injection of a median dose of 441 MegaBequerels of [11C]Ro15-4513. Metabolite-corrected arterial plasma input functions (parent plasma input functions, ppIFs) were generated for all scans. We quantified regional binding using six methods (12 variants), some of which were region-based (applied to the average time-activity curve within a region) and others were voxel-based: 1) Models requiring arterial ppIFs - regional reversible compartmental models with one and two tissue compartments (2kbv and 4kbv); 2) Regional and voxelwise Logan's graphical analyses (Logan et al., 1990), which required arterial ppIFs; 3) Model-free regional and voxelwise (exponential) spectral analyses (SA; (Cunningham and Jones, 1993)), which also required arterial ppIFs; 4) methods not requiring arterial ppIFs - voxelwise standardised uptake values (Kenney et al., 1941), and regional and voxelwise simplified reference tissue models (SRTM/SRTM2) using brainstem or alternatively cerebellum as pseudo-reference regions (Lammertsma and Hume, 1996; Gunn et al., 1997). To compare the variants, we sampled the mean values of the outcome parameters within six bilateral, non-reference grey matter regions-of-interest. Reliability was quantified in terms of median absolute percentage test-retest differences (MA-TDs; preferentially low) and between-subject coefficient of variation (BS-CV, preferentially high), both compounded by the intraclass correlation coefficient (ICC). These measures were compared between variants, with particular interest in the hippocampus. RESULTS Two of the six methods (5/12 variants) yielded reproducible data (i.e. MA-TD <10%): regional SRTMs and voxelwise SRTM2s, both using either the brainstem or the cerebellum; and voxelwise SA. However, the SRTMs using the brainstem yielded a lower median BS-CV (7% for regional, 7% voxelwise) than the other variants (8-11%), resulting in lower ICCs. The median ICCs across six regions were 0.89 (interquartile range 0.75-0.90) for voxelwise SA, 0.71 (0.64-0.84) for regional SRTM-cerebellum and 0.83 (0.70-0.86) for voxelwise SRTM-cerebellum. The ICCs for the hippocampus were 0.89 for voxelwise SA, 0.95 for regional SRTM-cerebellum and 0.93 for voxelwise SRTM-cerebellum. CONCLUSION Quantification of [11C]Ro15-4513 binding shows very good to excellent reproducibility with SRTM and with voxelwise SA which, however, requires an arterial ppIF. Quantification in the α5 subunit-rich hippocampus is particularly reliable. The very low expression of the α5 in the cerebellum (Fritschy and Mohler, 1995; Veronese et al., 2016) and the substantial α1 subunit density in this region may hamper the application of reference tissue methods.
Collapse
Affiliation(s)
- Colm J McGinnity
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK; Division of Imaging Sciences & Biomedical Engineering, King's College London, London, UK.
| | - Daniela A Riaño Barros
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK
| | - Lula Rosso
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK
| | - Mattia Veronese
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Gaia Rizzo
- Department of Information Engineering, University of Padova, Padova, Italy
| | | | - Rainer Hinz
- Wolfson Molecular Imaging Centre, University of Manchester, Manchester, UK
| | - Federico E Turkheimer
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Matthias J Koepp
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, UK; Epilepsy Society, Chalfont St Peter, UK
| | - Alexander Hammers
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK; Division of Imaging Sciences & Biomedical Engineering, King's College London, London, UK; The Neurodis Foundation, CERMEP - Imagerie du Vivant, Lyon, France
| |
Collapse
|
21
|
Chagraoui A, Skiba M, Thuillez C, Thibaut F. To what extent is it possible to dissociate the anxiolytic and sedative/hypnotic properties of GABAA receptors modulators? Prog Neuropsychopharmacol Biol Psychiatry 2016; 71:189-202. [PMID: 27495357 DOI: 10.1016/j.pnpbp.2016.08.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/21/2016] [Accepted: 08/01/2016] [Indexed: 01/16/2023]
Abstract
The relatively common view indicates a possible dissociation between the anxiolytic and sedative/hypnotic properties of benzodiazepines (BZs). Indeed, GABAA receptor (GABAAR) subtypes have specific cerebral distribution in distinct neural circuits. Thus, GABAAR subtype-selective drugs may be expected to perform distinct functions. However, standard behavioral test assays provide limited direction towards highlighting new action mechanisms of ligands targeting GABAARs. Automated behavioral tests, lack sensitivity as some behavioral characteristics or subtle behavioral changes of drug effects or that are not considered in the overall analysis (Ohl et al., 2001) and observation-based analyses are not always performed. In addition, despite the use of genetically engineered mice, any possible dissociation between the anxiolytic and sedative properties of BZs remains controversial. Moreover, the involvement the different subtypes of GABAAR subtypes in the anxious behavior and the mechanism of action of anxiolytic agents remains unclear since there has been little success in the pharmacological investigations so far. This raises the question of the involvement of the different subunits in anxiolytic-like and/or sedative effects; and the actual implication of these subunits, particularly, α-subunits in the modulation of sedation and/or anxiety-related disorders. This present review was prompted by several conflicting studies on the degree of involvement of these subunits in anxiolytic-like and/or sedative effects. To this end, we explored the GABAergic system, particularly, the role of different subunits containing synaptic GABAARs. We report herein the targeting gene encoding the different subunits and their contribution in anxiolytic-like and/or sedative actions, as well as, the mechanism underlying tolerance to BZs.
Collapse
Affiliation(s)
- A Chagraoui
- Inserm U982, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedecine, Normandy University, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France.
| | - M Skiba
- Inserm U982, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedecine, Normandy University, France
| | - C Thuillez
- Department of Pharmacology, Rouen University Hospital, Rouen, and INSERM U1096, Laboratory of New Pharmacological Targets for Endothelial Protection and Heart Failure, Institute for Research and Innovation in Biomedicine, Normandy University, France
| | - F Thibaut
- Department of Psychiatry, University Hospital Cochin (site Tarnier), University of Paris-Descartes and INSERM U 894 Laboratory of Psychiatry and Neurosciences, Paris, France
| |
Collapse
|
22
|
Sieghart W. Allosteric modulation of GABAA receptors via multiple drug-binding sites. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2014; 72:53-96. [PMID: 25600367 DOI: 10.1016/bs.apha.2014.10.002] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
GABAA receptors are ligand-gated ion channels composed of five subunits that can be opened by GABA and be modulated by multiple pharmacologically and clinically important drugs. Over the time, hundreds of compounds from different structural classes have been demonstrated to modulate, directly activate, or inhibit GABAA receptors, and most of these compounds interact with more than one binding site at these receptors. Crystal structures of proteins and receptors homologous to GABAA receptors as well as homology modeling studies have provided insights into the possible location of ligand interaction sites. Some of these sites have been identified by mutagenesis, photolabeling, and docking studies. For most of these ligands, however, binding sites are not known. Due to the high flexibility of GABAA receptors and the existence of multiple drug-binding sites, the unequivocal identification of interaction sites for individual drugs is extremely difficult. The existence of multiple GABAA receptor subtypes with distinct subunit composition, the contribution of distinct subunit sequences to binding sites of different receptor subtypes, as well as the observation that even subunits not directly contributing to a binding site are able to influence affinity and efficacy of drugs, contribute to a unique pharmacology of each GABAA receptor subtype. Thus, each receptor subtype has to be investigated to identify a possible subtype selectivity of a compound. Although multiple binding sites make GABAA receptor pharmacology even more complicated, the exploitation of ligand interaction with novel-binding sites also offers additional possibilities for a subtype-selective modulation of GABAA receptors.
Collapse
Affiliation(s)
- Werner Sieghart
- Department of Molecular Neurosciences, Center for Brain Research, Medical University Vienna, Vienna, Austria.
| |
Collapse
|
23
|
Martínez-Cué C, Delatour B, Potier MC. Treating enhanced GABAergic inhibition in Down syndrome: use of GABA α5-selective inverse agonists. Neurosci Biobehav Rev 2014; 46 Pt 2:218-27. [PMID: 24412222 DOI: 10.1016/j.neubiorev.2013.12.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 11/27/2013] [Accepted: 12/16/2013] [Indexed: 11/27/2022]
Abstract
Excess inhibition in the brain of individuals carrying an extra copy of chromosome 21 could be responsible for cognitive deficits observed throughout their lives. A change in the excitatory/inhibitory balance in adulthood would alter synaptic plasticity, potentially triggering learning and memory deficits. γ-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the mature central nervous system and binds to GABAA receptors, opens a chloride channel, and reduces neuronal excitability. In this review we discuss methods to alleviate neuronal inhibition in a mouse model of Down syndrome, the Ts65Dn mouse, using either an antagonist (pentylenetetrazol) or two different inverse agonists selective for the α5-subunit containing receptor. Both inverse agonists, which reduce inhibitory GABAergic transmission, could rescue learning and memory deficits in Ts65Dn mice. We also discuss safety issues since modulation of the excitatory-inhibitory balance to improve cognition without inducing seizures remains particularly difficult when using GABA antagonists.
Collapse
Affiliation(s)
- Carmen Martínez-Cué
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Benoît Delatour
- Institut du Cerveau et de Moelle Epinière, CNRS UMR7225, INSERM U1127, UPMC, IHUA-ICM, Hôpital Pitié-Salpêtrière, Paris, France
| | - Marie-Claude Potier
- Institut du Cerveau et de Moelle Epinière, CNRS UMR7225, INSERM U1127, UPMC, IHUA-ICM, Hôpital Pitié-Salpêtrière, Paris, France.
| |
Collapse
|
24
|
Fedorov O, Lingard H, Wells C, Monteiro OP, Picaud S, Keates T, Yapp C, Philpott M, Martin SJ, Felletar I, Marsden BD, Filippakopoulos P, Müller S, Knapp S, Brennan PE. [1,2,4]triazolo[4,3-a]phthalazines: inhibitors of diverse bromodomains. J Med Chem 2013; 57:462-76. [PMID: 24313754 PMCID: PMC3906316 DOI: 10.1021/jm401568s] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Bromodomains are gaining increasing interest as drug targets. Commercially sourced and de novo synthesized substituted [1,2,4]triazolo[4,3-a]phthalazines are potent inhibitors of both the BET bromodomains such as BRD4 as well as bromodomains outside the BET family such as BRD9, CECR2, and CREBBP. This new series of compounds is the first example of submicromolar inhibitors of bromodomains outside the BET subfamily. Representative compounds are active in cells exhibiting potent cellular inhibition activity in a FRAP model of CREBBP and chromatin association. The compounds described are valuable starting points for discovery of selective bromodomain inhibitors and inhibitors with mixed bromodomain pharmacology.
Collapse
Affiliation(s)
- Oleg Fedorov
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford , Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, U.K
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Guerrini G, Ciciani G, Costanzo A, Daniele S, Martini C, Ghelardini C, Di Cesare Mannelli L, Ciattini S. Synthesis of novel cognition enhancers with pyrazolo[5,1-c][1,2,4]benzotriazine core acting at γ-aminobutyric acid type A (GABA(A)) receptor. Bioorg Med Chem 2013; 21:2186-2198. [PMID: 23490154 DOI: 10.1016/j.bmc.2013.02.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 01/16/2013] [Accepted: 02/14/2013] [Indexed: 01/13/2023]
Abstract
Memory dysfunction associated with aging, neurodegenerative and psychiatric disorders represents an increasing medical need. Advances in research exploring the biological mechanisms underlying learning and memory have opened new potential approaches for development of memory-enhancing therapies addressed to selective neuronal targets. In this work, we synthesized some derivatives with a pyrazolo[5,1-c][1,2,4]benzotriazine core to identify ligands on GABAA receptors subtype (benzodiazepine site on GABAA-receptor) endowed with the potential of enhancing cognition activity without the side effects usually associated with non-selective GABAA modulators. In fact, there is much evidence that GABAA-R (γ-aminobutyric acid, type A receptor) subtype ligands have relevance in learning and memory. In vitro and in vivo tests have been performed. Pharmacological data indicate that compounds 7, 13, 14 and 22 act as dual functional modulators of GABAA-Rs (promnemonic and anxiolytic agents) while only compounds 3 and 10 stand out as selectively displaying good antiamnesic and procognitive activity (1 and 3 mg/kg, respectively).
Collapse
Affiliation(s)
- Gabriella Guerrini
- Dipartimento di Scienze Farmaceutiche, Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente attivi (HeteroBioLab) Università degli Studi di Firenze, Via U. Schiff, 6, 50019 Polo Scientifico, Sesto Fiorentino, Firenze, Italy.
| | - Giovanna Ciciani
- Dipartimento di Scienze Farmaceutiche, Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente attivi (HeteroBioLab) Università degli Studi di Firenze, Via U. Schiff, 6, 50019 Polo Scientifico, Sesto Fiorentino, Firenze, Italy
| | - Annarella Costanzo
- Dipartimento di Scienze Farmaceutiche, Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente attivi (HeteroBioLab) Università degli Studi di Firenze, Via U. Schiff, 6, 50019 Polo Scientifico, Sesto Fiorentino, Firenze, Italy
| | - Simona Daniele
- Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, Università degli Studi di Pisa, via Bonanno, 6, 56126 Pisa, Italy
| | - Claudia Martini
- Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, Università degli Studi di Pisa, via Bonanno, 6, 56126 Pisa, Italy
| | - Carla Ghelardini
- Dipartimento di Farmacologia Preclinica e Clinica Aiazzi-Mancini, Università degli Studi di Firenze, Viale Pieraccini, 6, 50139 Firenze, Italy
| | - Lorenzo Di Cesare Mannelli
- Dipartimento di Farmacologia Preclinica e Clinica Aiazzi-Mancini, Università degli Studi di Firenze, Viale Pieraccini, 6, 50139 Firenze, Italy
| | - Samuele Ciattini
- Centro di Cristallografia, Università degli Studi di Firenze, Via della Lastruccia, 3, 50019 Polo Scientifico, Sesto Fiorentino, Firenze, Italy
| |
Collapse
|
26
|
PWZ-029, an inverse agonist selective for α₅ GABAA receptors, improves object recognition, but not water-maze memory in normal and scopolamine-treated rats. Behav Brain Res 2012; 241:206-13. [PMID: 23261875 DOI: 10.1016/j.bbr.2012.12.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 12/07/2012] [Accepted: 12/10/2012] [Indexed: 01/03/2023]
Abstract
Inverse agonism at the benzodiazepine site of α(5) subunit-containing GABA(A) receptors is an attractive approach for the development of putative cognition-enhancing compounds, which are still far from clinical application. Several ligands with binding and/or functional selectivity for α(5) GABA(A) receptors have been synthesized and tested in a few animal models. PWZ-029 is an α(5) GABA(A) selective inverse agonist whose memory enhancing effects were demonstrated in the passive avoidance task in rats and in Pavlovian fear conditioning in mice. In the present study we investigated the effects of PWZ-029 administration in novel object recognition test and Morris water maze, in normal and scopolamine-treated rats. All the three doses of PWZ-029 (2, 5 and 10 mg/kg) improved object recognition after the 24-h delay period, as shown by significant differences between the exploration times of the novel and old object, and the respective discrimination indices. PWZ-029 (2 mg/kg) also successfully reversed the 0.3 mg/kg scopolamine-induced deficit in recognition memory after the 1-h delay. In the Morris water maze test, PWZ-029 (5, 10 and 15 mg/kg) did not significantly influence swim patterns, either during five acquisition days or during the treatment-free probe trial. PWZ-029 (2, 5 and 10 mg/kg) also proved to be ineffective in the reversal of the 1mg/kg scopolamine-induced memory impairment in the water maze. The present mixed results encourage use of a variety of tests and experimental conditions in order to increase the predictability of preclinical testing of selective α(5) GABA(A) inverse agonists.
Collapse
|
27
|
Bagal SK, Brown AD, Cox PJ, Omoto K, Owen RM, Pryde DC, Sidders B, Skerratt SE, Stevens EB, Storer RI, Swain NA. Ion Channels as Therapeutic Targets: A Drug Discovery Perspective. J Med Chem 2012; 56:593-624. [DOI: 10.1021/jm3011433] [Citation(s) in RCA: 198] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sharan K. Bagal
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Alan D. Brown
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Peter J. Cox
- Pfizer Neusentis, The
Portway Building, Granta Park, Great Abington, Cambridge, CB21
6GS, U.K
| | - Kiyoyuki Omoto
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Robert M. Owen
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - David C. Pryde
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Benjamin Sidders
- Pfizer Neusentis, The
Portway Building, Granta Park, Great Abington, Cambridge, CB21
6GS, U.K
| | - Sarah E. Skerratt
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Edward B. Stevens
- Pfizer Neusentis, The
Portway Building, Granta Park, Great Abington, Cambridge, CB21
6GS, U.K
| | - R. Ian Storer
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Nigel A. Swain
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| |
Collapse
|
28
|
Lingford-Hughes A, Reid AG, Myers J, Feeney A, Hammers A, Taylor LG, Rosso L, Turkheimer F, Brooks DJ, Grasby P, Nutt DJ. A [11C]Ro15 4513 PET study suggests that alcohol dependence in man is associated with reduced α5 benzodiazepine receptors in limbic regions. J Psychopharmacol 2012; 26:273-81. [PMID: 20870689 DOI: 10.1177/0269881110379509] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Preclinical evidence suggests the α5 subtype of the GABA-benzodiazepine receptor is involved in some of the actions of alcohol and in memory. The positron emission tomography (PET) tracer, [(11)C]Ro15 4513 shows relative selectivity in labelling the α5 subtype over the other GABA-benzodiazepine receptor subtypes in limbic regions of the brain. We used this tracer to investigate the distribution of α5 subtype availability in human alcohol dependence and its relationship to clinical variables. Abstinent (>6 weeks) alcohol-dependent men and healthy male controls underwent an [(11)C]Ro15 4513 PET scan. We report [(11)C]Ro15 4513 brain uptake for 8 alcohol-dependent men and 11 healthy controls. We found a significant reduction in [(11)C]Ro15 4513 binding in the nucleus accumbens, parahippocampal gyri, right hippocampus and amygdala in the alcohol-dependent compared with the healthy control group. Levels of [(11)C]Ro15 4513 binding in both hippocampi were significantly and positively associated with performance on a delayed verbal memory task in the alcohol-dependent but not the control group. We speculate that the reduced limbic [(11)C]Ro15 4513 binding seen here results from the effects of alcohol, though we cannot currently distinguish whether they are compensatory in nature or evidence of brain toxicity.
Collapse
Affiliation(s)
- Anne Lingford-Hughes
- Psychopharmacology Unit, Dorothy Hodgkin Building, University of Bristol, Bristol, UK.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
The GABA system in anxiety and depression and its therapeutic potential. Neuropharmacology 2012; 62:42-53. [DOI: 10.1016/j.neuropharm.2011.08.040] [Citation(s) in RCA: 348] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 08/23/2011] [Indexed: 01/01/2023]
|
30
|
Chronic Treatment with a Promnesiant GABA-A α5-Selective Inverse Agonist Increases Immediate Early Genes Expression during Memory Processing in Mice and Rectifies Their Expression Levels in a Down Syndrome Mouse Model. Adv Pharmacol Sci 2011; 2011:153218. [PMID: 22028705 PMCID: PMC3199058 DOI: 10.1155/2011/153218] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 07/27/2011] [Accepted: 07/31/2011] [Indexed: 12/20/2022] Open
Abstract
Decrease of GABAergic transmission has been proposed to improve memory functions. Indeed, inverse agonists selective for α5 GABA-A-benzodiazepine receptors (α5IA) have promnesiant activity. Interestingly, we have recently shown that α5IA can rescue cognitive deficits in Ts65Dn mice, a Down syndrome mouse model with altered GABAergic transmission. Here, we studied the impact of chronic treatment with α5IA on gene expression in the hippocampus of Ts65Dn and control euploid mice after being trained in the Morris water maze task. In euploid mice, chronic treatment with α5IA increased IEGs expression, particularly of c-Fos and Arc genes. In Ts65Dn mice, deficits of IEGs activation were completely rescued after treatment with α5IA. In addition, normalization of Sod1 overexpression in Ts65Dn mice after α5IA treatment was observed. IEG expression regulation after α5IA treatment following behavioral stimulation could be a contributing factor for both the general promnesiant activity of α5IA and its rescuing effect in Ts65Dn mice alongside signaling cascades that are critical for memory consolidation and cognition.
Collapse
|
31
|
Braudeau J, Delatour B, Duchon A, Pereira PL, Dauphinot L, de Chaumont F, Olivo-Marin JC, Dodd RH, Hérault Y, Potier MC. Specific targeting of the GABA-A receptor α5 subtype by a selective inverse agonist restores cognitive deficits in Down syndrome mice. J Psychopharmacol 2011; 25:1030-42. [PMID: 21693554 PMCID: PMC3160204 DOI: 10.1177/0269881111405366] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
An imbalance between inhibitory and excitatory neurotransmission has been proposed to contribute to altered brain function in individuals with Down syndrome (DS). Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system and accordingly treatment with GABA-A antagonists can efficiently restore cognitive functions of Ts65Dn mice, a genetic model for DS. However, GABA-A antagonists are also convulsant which preclude their use for therapeutic intervention in DS individuals. Here, we have evaluated safer strategies to release GABAergic inhibition using a GABA-A-benzodiazepine receptor inverse agonist selective for the α5-subtype (α5IA). We demonstrate that α5IA restores learning and memory functions of Ts65Dn mice in the novel-object recognition and in the Morris water maze tasks. Furthermore, we show that following behavioural stimulation, α5IA enhances learning-evoked immediate early gene products in specific brain regions involved in cognition. Importantly, acute and chronic treatments with α5IA do not induce any convulsant or anxiogenic effects that are associated with GABA-A antagonists or non-selective inverse agonists of the GABA-A-benzodiazepine receptors. Finally, chronic treatment with α5IA did not induce histological alterations in the brain, liver and kidney of mice. Our results suggest that non-convulsant α5-selective GABA-A inverse agonists could improve learning and memory deficits in DS individuals.
Collapse
Affiliation(s)
- J Braudeau
- Centre de Recherche de l'Institut du
Cerveau et de Moelle Epinière, CNRS UMR7225, INSERM UMRS 975, UPMC, Paris,
France.,CNRS, Lab NAMC, UMR8620, Université
Paris Sud, Orsay, France
| | - B Delatour
- Centre de Recherche de l'Institut du
Cerveau et de Moelle Epinière, CNRS UMR7225, INSERM UMRS 975, UPMC, Paris,
France.,CNRS, Lab NAMC, UMR8620, Université
Paris Sud, Orsay, France
| | - A Duchon
- Institut de Génétique et de Biologie
Moléculaire et Cellulaire (IGBMC), Institut National de Santé et de Recherche
Médicale (INSERM) U964/Centre National de Recherche Scientifique (CNRS) UMR
1704/Université de Strasbourg, 67404 Illkirch, France.,Institut Clinique de la Souris (ICS),
Groupe d'Intérêt Economique Centre Européen de Recherche en Biologie et en Médecine
(GIE-CERBM), INSERM, CNRS, Université de Strasbourg, Illkirch, France
| | - P Lopes Pereira
- Institut de Génétique et de Biologie
Moléculaire et Cellulaire (IGBMC), Institut National de Santé et de Recherche
Médicale (INSERM) U964/Centre National de Recherche Scientifique (CNRS) UMR
1704/Université de Strasbourg, 67404 Illkirch, France
| | - L Dauphinot
- Centre de Recherche de l'Institut du
Cerveau et de Moelle Epinière, CNRS UMR7225, INSERM UMRS 975, UPMC, Paris,
France
| | - F de Chaumont
- Institut Pasteur, Quantitative Image
Analysis Unit, CNRS URA 2582, 75015 Paris, France
| | - J-C Olivo-Marin
- Institut Pasteur, Quantitative Image
Analysis Unit, CNRS URA 2582, 75015 Paris, France
| | - RH Dodd
- Institut de Chimie des Substances
Naturelles - CNRS UPR 2301, Gif-sur-Yvette, France
| | - Y Hérault
- Institut de Génétique et de Biologie
Moléculaire et Cellulaire (IGBMC), Institut National de Santé et de Recherche
Médicale (INSERM) U964/Centre National de Recherche Scientifique (CNRS) UMR
1704/Université de Strasbourg, 67404 Illkirch, France.,Institut Clinique de la Souris (ICS),
Groupe d'Intérêt Economique Centre Européen de Recherche en Biologie et en Médecine
(GIE-CERBM), INSERM, CNRS, Université de Strasbourg, Illkirch, France
| | - M-C Potier
- Centre de Recherche de l'Institut du
Cerveau et de Moelle Epinière, CNRS UMR7225, INSERM UMRS 975, UPMC, Paris,
France.,M-C Potier, Centre de Recherche de
l'Institut du Cerveau et de Moelle Epinière, CNRS UMR7225, INSERM UMRS 975,
UPMC, 75013 Paris, France
| |
Collapse
|
32
|
Abstract
GABA is the major inhibitory neurotransmitter in the adult mammalian CNS. The ionotropic GABA type A receptors (GABA(A)Rs) belong to the Cys-loop family of receptors. Each member of the family is a large pentameric protein in which each subunit traverses the cell membrane four times. Within this family, the GABA type A receptors are particularly important for their rich pharmacology as they are targets for a range of therapeutically important drugs, including the benzodiazepines, barbiturates, neuroactive steroids and anesthetics. This review discusses new insights into receptor properties that allow us to begin to relate the structure of an individual receptor to its functional and pharmacological properties.
Collapse
|
33
|
Głowacka IE, Cieślak M, Piotrowska DG. Synthesis of Novel 1-Hydroxy-2-(1,2,3-triazol-1-yl)ethylphosphonates and 2-Hydroxy-3-(1,2,3-triazol-1-yl)propylphosphonates. PHOSPHORUS SULFUR 2011. [DOI: 10.1080/10426507.2010.494646] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Iwona E. Głowacka
- a Bioorganic Chemistry Laboratory, Faculty of Pharmacy , Medical University of Łódź , Poland
| | - Marcin Cieślak
- b Department of Bioorganic Chemistry , Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences , Łódź , Poland
| | - Dorota G. Piotrowska
- a Bioorganic Chemistry Laboratory, Faculty of Pharmacy , Medical University of Łódź , Poland
| |
Collapse
|
34
|
Vinkers CH, Mirza NR, Olivier B, Kahn RS. The inhibitory GABA system as a therapeutic target for cognitive symptoms in schizophrenia: investigational agents in the pipeline. Expert Opin Investig Drugs 2011; 19:1217-33. [PMID: 20812877 DOI: 10.1517/13543784.2010.513382] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD Cognitive impairments associated with schizophrenia include neuropsychological deficits in attention, working memory, learning and executive function. Because these cognitive deficits precede the onset of psychosis, are present in non-affected relatives and constitute the best predictor of functional outcome, they are a cardinal clinical feature in schizophrenia. Currently, no effective treatment for the cognitive symptoms in schizophrenia exists. AREAS COVERED IN THIS REVIEW There is evidence that the inhibitory GABA system is affected in schizophrenia, suggesting that cognitive impairments associated with schizophrenia may be effectively treated by drugs that modulate the GABA(A) receptor. However, classical benzodiazepines produce cognitive impairments and are associated with numerous side effects. The recent development of compounds with selective efficacy for different α subunits at the benzodiazepine site of the GABA(A) receptor has renewed interest for the therapeutic potential of GABAergic drugs. WHAT THE READER WILL GAIN This review summarizes the involvement of the inhibitory GABA system in the cognitive abnormalities of schizophrenia and discusses putative (selective) GABAergic cognition-enhancing drugs for schizophrenia. TAKE HOME MESSAGE If cognitive abnormalities in schizophrenic individuals are the result of GABAergic dysfunction, selectively modulating the GABA system could comprise a promising therapeutic intervention for cognitive symptoms in schizophrenia.
Collapse
Affiliation(s)
- Christiaan H Vinkers
- Department of Psychiatry, University Medical Center Utrecht, Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands
| | | | | | | |
Collapse
|
35
|
Johnstone TB, Gu Z, Yoshimura RF, Villegier AS, Hogenkamp DJ, Whittemore ER, Huang JC, Tran MB, Belluzzi JD, Yakel JL, Gee KW. Allosteric modulation of related ligand-gated ion channels synergistically induces long-term potentiation in the hippocampus and enhances cognition. J Pharmacol Exp Ther 2010; 336:908-15. [PMID: 21159751 DOI: 10.1124/jpet.110.176255] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
α5 Subunit-containing GABA(A) receptors (GABA(A)Rs) and α7 neuronal nicotinic-acetylcholine receptors (nAChRs) are members of the Cys-loop family of ligand-gated ion channels (LGICs) that mediate cognitive and attentional processes in the hippocampus. α5 GABA(A)Rs alter network activity by tonic inhibition of CA1/CA3 pyramidal cells of the hippocampus. Postsynaptic α7 nAChRs in the hippocampus regulate inhibitory GABAergic interneuron activity required for synchronization of pyramidal neurons in the CA1, whereas presynaptic α7 nAChRs regulate glutamate release. Can simultaneous allosteric modulation of these LGICs produce synergistic effects on cognition? We show that combined transient application of two allosteric modulators that individually 1) inhibit α5 GABA(A)Rs and 2) enhance α7 nAChRs causes long-term potentiation (LTP) of mossy fiber stimulation-induced excitatory postsynaptic currents (EPSC) from CA1 pyramidal neurons of rat hippocampal slices. The LTP effect evoked by two compounds is replicated by 3-(2,5-difluorophenyl)-6-(N-ethylindol-5-yl)-1,2,4-triazolo[4,3-b]pyridazine (522-054), a compound we designed to simultaneously inhibit α5 GABA(A)Rs and enhance α7 nAChRs. Selective antagonists for either receptor block sustained EPSC potentiation produced by 522-054. In vivo, 522-054 enhances performance in the radial arm maze and facilitates attentional states in the five-choice serial reaction time trial with similar receptor antagonist sensitivity. These observations may translate into therapeutic utility of dual action compounds in diseases of hippocampal-based cognitive impairment.
Collapse
Affiliation(s)
- Timothy B Johnstone
- Department of Pharmacology, School of Medicine, University of California, Irvine, California, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Makkar SR, Zhang SQ, Cranney J. Behavioral and neural analysis of GABA in the acquisition, consolidation, reconsolidation, and extinction of fear memory. Neuropsychopharmacology 2010; 35:1625-52. [PMID: 20410874 PMCID: PMC3055480 DOI: 10.1038/npp.2010.53] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Revised: 03/17/2010] [Accepted: 03/22/2010] [Indexed: 11/09/2022]
Abstract
The current review systematically documents the role of gamma-amino-butyric acid (GABA) in different aspects of fear memory-acquisition and consolidation, reconsolidation, and extinction, and attempts to resolve apparent contradictions in the data in order to identify the function of GABA(A) receptors in fear memory. First, numerous studies have shown that pre- and post-training administration of drugs that facilitate GABAergic transmission disrupt the initial formation of fear memories, indicating a role for GABA(A) receptors, possibly within the amygdala and hippocampus, in the acquisition and consolidation of fear memories. Similarly, recent evidence indicates that these drugs are also detrimental to the restorage of fear memories after their reactivation. This suggests a role for GABA(A) receptors in the reconsolidation of fear memories, although the precise neural circuits are yet to be identified. Finally, research regarding the role of GABA in extinction has shown that GABAergic transmission is also disruptive to the formation of newly acquired extinction memories. We argue that contradictions to these patterns are the result of variations in (a) the location of drug infusion, (b) the dosage of the drug and/or (c) the time point of drug administration. The question of whether these GABA-induced memory deficits reflect deficits in retrieval is discussed. Overall, the evidence implies that the processes mediating memory stability consequent to initial fear learning, memory reactivation, and extinction training are dependent on a common mechanism of reduced GABAergic neurotransmission.
Collapse
Affiliation(s)
- Steve R Makkar
- School of Psychology, University of New South Wales, Sydney, NSW, Australia
| | - Shirley Q Zhang
- School of Psychology, University of New South Wales, Sydney, NSW, Australia
| | - Jacquelyn Cranney
- School of Psychology, University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
37
|
Abstract
Alzheimer's disease is a progressive neurodegenerative disease for which no cure exists. There is a substantial need for new therapies that offer improved symptomatic benefit and disease-slowing capabilities. In recent decades there has been substantial progress in understanding the molecular and cellular changes associated with Alzheimer's disease pathology. This has resulted in identification of a large number of new drug targets. These targets include, but are not limited to, therapies that aim to prevent production of or remove the amyloid-beta protein that accumulates in neuritic plaques; to prevent the hyperphosphorylation and aggregation into paired helical filaments of the microtubule-associated protein tau; and to keep neurons alive and functioning normally in the face of these pathologic challenges. We provide a review of these targets for drug development.
Collapse
Affiliation(s)
- Joshua D Grill
- Mary S. Easton Center for Alzheimer's Disease Research, Deane F. Johnson Center for Neurotherapeutics, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
| | | |
Collapse
|
38
|
Preclinical and clinical pharmacology of the GABAA receptor α5 subtype-selective inverse agonist α5IA. Pharmacol Ther 2010; 125:11-26. [DOI: 10.1016/j.pharmthera.2009.09.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 09/01/2009] [Indexed: 11/17/2022]
|
39
|
γ-Aminobutyric Acid Type A (GABAA) Receptor Subtype Inverse Agonists as Therapeutic Agents in Cognition. Methods Enzymol 2010; 485:197-211. [DOI: 10.1016/b978-0-12-381296-4.00011-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
|
40
|
Abstract
Complex brains have developed specialized mechanisms for the grouping of principal cells into temporal coalitions of local or distant networks: the inhibitory interneuron ‘clocking’ networks. They consist of GABAergic (where GABA is γ-aminobutyric acid) interneurons of a rich diversity. In cortical circuits, these neurons control spike timing of the principal cells, sculpt neuronal rhythms, select cell assemblies and implement brain states. On the basis of these considerations, the deficits in cognition, emotion and perception in psychiatric disorders such as anxiety, depression or schizophrenia are considered to manifest themselves through a dysregulation of the inhibitory interneuron ‘clocking’ network as a final common denominator, irrespective of the diverse underlying disease pathologies. The diversity of GABAergic interneurons is paralleled by a corresponding diversity of GABAA receptors in network regulation. The region-, cell- and domain-specific location of these receptor subtypes offers the possibility to gain functional insights into the role of behaviourally relevant neuronal circuits. Using genetic manipulation, the regulation of anxiety behaviour was attributed to neuronal circuits characterized by the expression of α2-GABAA receptors. Neurons expressing α3-GABAA receptors, located mainly in aminergic and basal forebrain cholinergic neurons, were related to a hyperdopaminergic phenotype, typical of schizophrenic symptoms. Temporal and spatial memory were selectively modulated by extrasynaptic α5-GABAA receptors. Chronic pathological pain was under the regulation of spinal and cortical α2- (and α3-) GABAA receptors. Thus the relevance of the diversity of inhibitory GABAA receptor subtypes for the regulation of cognition, emotion and memory is increasingly being recognized. The clinical proof-of-concept of a subtype-specific pharmacology is most advanced for the alleviation of cognitive dysfunctions in schizophrenia, based on the treatment of patients with an α2/α3-GABAA receptor ligand.
Collapse
|
41
|
Buettelmann B, Ballard TM, Gasser R, Fischer H, Hernandez MC, Knoflach F, Knust H, Stadler H, Thomas AW, Trube G. Imidazo[1,5-a][1,2,4]-triazolo[1,5-d][1,4]benzodiazepines as potent and highly selective GABAA α5 inverse agonists with potential for the treatment of cognitive dysfunction. Bioorg Med Chem Lett 2009; 19:5958-61. [DOI: 10.1016/j.bmcl.2009.08.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 08/04/2009] [Accepted: 08/05/2009] [Indexed: 10/20/2022]
|
42
|
Discovery of the imidazo[1,5-a][1,2,4]-triazolo[1,5-d][1,4]benzodiazepine scaffold as a novel, potent and selective GABAA α5 inverse agonist series. Bioorg Med Chem Lett 2009; 19:5746-52. [DOI: 10.1016/j.bmcl.2009.07.153] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 07/30/2009] [Accepted: 07/31/2009] [Indexed: 01/16/2023]
|
43
|
Głowacka IE. Synthesis of enantiomerically pure diethyl (R)- and (S)-2-hydroxy-3-(1,2,3-triazol-1-yl)propylphosphonates. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.tetasy.2009.09.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
44
|
The complexity of the GABAA receptor shapes unique pharmacological profiles. Drug Discov Today 2009; 14:866-75. [DOI: 10.1016/j.drudis.2009.06.009] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 05/08/2009] [Accepted: 06/16/2009] [Indexed: 01/09/2023]
|
45
|
Charych EI, Liu F, Moss SJ, Brandon NJ. GABA(A) receptors and their associated proteins: implications in the etiology and treatment of schizophrenia and related disorders. Neuropharmacology 2009; 57:481-95. [PMID: 19631671 DOI: 10.1016/j.neuropharm.2009.07.027] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Revised: 07/02/2009] [Accepted: 07/13/2009] [Indexed: 02/05/2023]
Abstract
Gamma-aminobutyric acid type A (GABA(A)) receptors play an important role in mediating fast synaptic inhibition in the brain. They are ubiquitously expressed in the CNS and also represent a major site of action for clinically relevant drugs. Recent technological advances have greatly clarified the molecular and cellular roles played by distinct GABA(A) receptor subunit classes and isoforms in normal brain function. At the same time, postmortem and genetic studies have linked neuropsychiatric disorders including schizophrenia and bipolar disorder with GABAergic neurotransmission and various specific GABA(A) receptor subunits, while evidence implicating GABA(A)R-associated proteins is beginning to emerge. In this review we discuss the mounting genetic, molecular, and cellular evidence pointing toward a role for GABA(A) receptor heterogeneity in both schizophrenia etiology and therapeutic development. Finally, we speculate on the relationship between schizophrenia-related disorders and selected GABA(A) receptor associated proteins, key regulators of GABA(A) receptor trafficking, targeting, clustering, and anchoring that often carry out these functions in a subtype-specific manner.
Collapse
Affiliation(s)
- Erik I Charych
- Wyeth Research, Neuroscience Discovery, Princeton NJ 08852, USA.
| | | | | | | |
Collapse
|
46
|
Grimwood S, Hartig PR. Target site occupancy: Emerging generalizations from clinical and preclinical studies. Pharmacol Ther 2009; 122:281-301. [DOI: 10.1016/j.pharmthera.2009.03.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Accepted: 03/04/2009] [Indexed: 01/17/2023]
|
47
|
Powell SB, Zhou X, Geyer MA. Prepulse inhibition and genetic mouse models of schizophrenia. Behav Brain Res 2009; 204:282-94. [PMID: 19397931 DOI: 10.1016/j.bbr.2009.04.021] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 04/15/2009] [Accepted: 04/19/2009] [Indexed: 12/26/2022]
Abstract
Mutant mouse models related to schizophrenia have been based primarily on the pathophysiology of schizophrenia, the known effects of antipsychotic drugs, and candidate genes for schizophrenia. Sensorimotor gating deficits in schizophrenia patients, as indexed by measures of prepulse inhibition of startle (PPI), have been well characterized and suggested to meet the criteria as a useful endophenotype in human genetic studies. PPI refers to the ability of a non-startling "prepulse" to inhibit responding to the subsequent startling stimulus or "pulse." Because of the cross-species nature of PPI, it has been used primarily in pharmacological animal models to screen putative antipsychotic medications. As techniques in molecular genetics have progressed over the past 15 years, PPI has emerged as a phenotype used in assessing genetic mouse models of relevance to schizophrenia. In this review, we provide a selected overview of the use of PPI in mouse models of schizophrenia and discuss the contribution and usefulness of PPI as a phenotype in the context of genetic mouse models. To that end, we discuss mutant mice generated to address hypotheses regarding the pathophysiology of schizophrenia and candidate genes (i.e., hypothesis driven). We also briefly discuss the usefulness of PPI in phenotype-driven approaches in which a PPI phenotype could lead to "bottom up" approaches of identifying novel genes of relevance to PPI (i.e., hypothesis generating).
Collapse
Affiliation(s)
- Susan B Powell
- Department of Psychiatry, University of California San Diego, 9500 Gilman Dr. MC0804, La Jolla, CA 92093, United States.
| | | | | |
Collapse
|
48
|
Roland JJ, Savage LM. Blocking GABA-A receptors in the medial septum enhances hippocampal acetylcholine release and behavior in a rat model of diencephalic amnesia. Pharmacol Biochem Behav 2009; 92:480-7. [PMID: 19463263 PMCID: PMC2687320 DOI: 10.1016/j.pbb.2009.01.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Revised: 01/19/2009] [Accepted: 01/23/2009] [Indexed: 11/21/2022]
Abstract
Wernicke-Korsakoff syndrome (WKS), a form of diencephalic amnesia caused by thiamine deficiency, results in severe anterograde memory loss. Pyrithiamine-induced thiamine deficiency (PTD), an animal model of WKS, produces cholinergic abnormalities including decreased functional hippocampal acetylcholine (ACh) release and poor spatial memory. Increasing hippocampal ACh levels has increased performance in PTD animals. Intraseptal bicuculline (GABA(A) antagonist) augments hippocampal ACh release in normal animals and we found it (0.50 microg/microl and 0.75 microg/microl) also increased in-vivo hippocampal ACh release in PTD animals. However, the 0.75 microg/microl dose produced a greater change in hippocampal ACh release in control animals. The 0.50 microg/microl dose of bicuculline was then selected to determine if it could enhance spontaneous alternation performance in PTD animals. This dose of bicuculline significantly increased hippocampal ACh levels above baseline in both PTD and control rats and resulted in complete behavioral recovery in PTD animals, without altering performance in control rats. This suggests that balancing ACh-GABA interactions in the septohippocampal circuit may be an effective therapeutic approach in certain amnestic syndromes.
Collapse
Affiliation(s)
- Jessica J Roland
- Behavioral Neuroscience Program, Department of Psychology, Binghamton University-State University of New York, NY, USA.
| | | |
Collapse
|
49
|
Atack JR, Eng WS, Gibson RE, Ryan C, Francis B, Sohal B, Dawson GR, Hargreaves RJ, Burns HD. The plasma-occupancy relationship of the novel GABAA receptor benzodiazepine site ligand, alpha5IA, is similar in rats and primates. Br J Pharmacol 2009; 157:796-803. [PMID: 19422390 DOI: 10.1111/j.1476-5381.2009.00216.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE alpha5IA (3-(5-methylisoxazol-3-yl)-6-[(1-methyl-1,2,3-triazol-4-yl)methyloxy]-1,2,4-triazolo[3,4-a]phthalazine) is a triazolophthalazine with subnanomolar affinity for alpha1-, alpha2-, alpha3- and alpha5-containing GABA(A) receptors. Here we have evaluated the relationship between plasma alpha5IA concentrations and benzodiazepine binding site occupancy in rodents and primates (rhesus monkey). EXPERIMENTAL APPROACH In awake rats, occupancy was measured at various times after oral dosing with alpha5IA (0.03-30 mgxkg(-1)) using an in vivo {[(3)H]flumazenil (8-fluoro 5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylic acid ethyl ester)} binding assay. In anaesthetized rhesus monkeys, occupancy was measured using {[(123)I]iomazenil (ethyl 5,6-dihydro-7-iodo-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylic acid ethyl ester)} gamma-scintigraphy and a bolus/infusion paradigm. In both rat and rhesus monkey, the plasma drug concentration corresponding to 50% occupancy (EC(50)) was calculated. KEY RESULTS In rats, alpha5IA occupancy was dose- and time-dependent with maximum occupancy occurring within the first 2 h. However, rat plasma EC(50) was time-independent, ranging from 42 to 67 ngxmL(-1) over a 24 h time course with the average being 52 ngxmL(-1) (i.e. occupancy decreased as plasma drug concentrations fell). In rhesus monkeys, the EC(50) for alpha5IA displacing steady-state [(123)I]iomazenil binding was 57 ngxmL(-1). CONCLUSIONS AND IMPLICATIONS Rat plasma EC(50) values did not vary as a function of time indicating that alpha5IA dissociates readily for the GABA(A) receptor in vivo. These data also suggest that despite the different assays used (terminal assays of [(3)H]flumazenil in vivo binding in rats and [(123)I]iomazenil gamma-scintigraphy in anaesthetized rhesus monkeys), these techniques produced similar plasma alpha5IA EC(50) values (52 and 57 ngxmL(-1) respectively) and that the plasma-occupancy relationship for alpha5IA translates across these two species.
Collapse
Affiliation(s)
- John R Atack
- Merck Sharp and Dohme Research Laboratories, The Neuroscience Research Centre, Harlow, Essex, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Taherpour AA, Kheradmand K. One-pot microwave-assisted solvent free synthesis of simple alkyl 1,2,3-triazole-4-carboxylates by using trimethylsilyl azide. J Heterocycl Chem 2009. [DOI: 10.1002/jhet.36] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|