1
|
Li YT, Zhang C, Han JC, Shang YX, Chen ZH, Cui GB, Wang W. Neuroimaging features of cognitive impairments in schizophrenia and major depressive disorder. Ther Adv Psychopharmacol 2024; 14:20451253241243290. [PMID: 38708374 PMCID: PMC11070126 DOI: 10.1177/20451253241243290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 03/14/2024] [Indexed: 05/07/2024] Open
Abstract
Cognitive dysfunctions are one of the key symptoms of schizophrenia (SZ) and major depressive disorder (MDD), which exist not only during the onset of diseases but also before the onset, even after the remission of psychiatric symptoms. With the development of neuroimaging techniques, these non-invasive approaches provide valuable insights into the underlying pathogenesis of psychiatric disorders and information of cognitive remediation interventions. This review synthesizes existing neuroimaging studies to examine domains of cognitive impairment, particularly processing speed, memory, attention, and executive function in SZ and MDD patients. First, white matter (WM) abnormalities are observed in processing speed deficits in both SZ and MDD, with distinct neuroimaging findings highlighting WM connectivity abnormalities in SZ and WM hyperintensity caused by small vessel disease in MDD. Additionally, the abnormal functions of prefrontal cortex and medial temporal lobe are found in both SZ and MDD patients during various memory tasks, while aberrant amygdala activity potentially contributes to a preference to negative memories in MDD. Furthermore, impaired large-scale networks including frontoparietal network, dorsal attention network, and ventral attention network are related to attention deficits, both in SZ and MDD patients. Finally, abnormal activity and volume of the dorsolateral prefrontal cortex (DLPFC) and abnormal functional connections between the DLPFC and the cerebellum are associated with executive dysfunction in both SZ and MDD. Despite these insights, longitudinal neuroimaging studies are lacking, impeding a comprehensive understanding of cognitive changes and the development of early intervention strategies for SZ and MDD. Addressing this gap is critical for advancing our knowledge and improving patient prognosis.
Collapse
Affiliation(s)
- Yu-Ting Li
- Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Chi Zhang
- Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi’an, Shaanxi, China
- Shaanxi University of Chinese Medicine, Xianyang, Shaanxi, China
| | - Jia-Cheng Han
- Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Yu-Xuan Shang
- Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Zhu-Hong Chen
- Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Guang-Bin Cui
- Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi’an 710038, Shaanxi, China
| | - Wen Wang
- Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi’an 710038, Shaanxi, China
| |
Collapse
|
2
|
Burns LH, Pei Z, Wang HY. Targeting α7 nicotinic acetylcholine receptors and their protein interactions in Alzheimer's disease drug development. Drug Dev Res 2023; 84:1085-1095. [PMID: 37291958 DOI: 10.1002/ddr.22085] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/09/2023] [Accepted: 05/29/2023] [Indexed: 06/10/2023]
Abstract
The decades-old cholinergic hypothesis of Alzheimer's disease (AD) led to clinical testing and FDA approval of acetylcholinesterase inhibitor drugs. Subsequently, the α7 nicotinic acetylcholine receptor (α7nAChR) was proposed as a new drug target for enhancing cholinergic neurotransmission. Nearly simultaneously, soluble amyloid β1-42 (Aβ42 ) was shown to bind α7nAChR with picomolar affinity to activate kinases that hyperphosphorylate tau, the precursor to tau-containing tangles. Multiple biopharmaceutical companies explored α7nAChR as a drug target for AD, mostly to enhance neurotransmission. Directly targeting α7nAChR proved to be a drug development challenge. The ultra-high-affinity interaction between Aβ42 and α7nAChR posed a significant hurdle for direct competition in the AD brain. The receptor rapidly desensitizes, undermining efficacy of agonists. Drug discovery approaches therefore included partial agonists and allosteric modulators of α7nAChR. After substantial effort, numerous drug candidates were abandoned due to lack of efficacy or drug-related toxicities. As alternatives, proteins interacting with α7nAChR were sought. In 2016, a novel nAChR regulator was identified, but no drug candidates have emerged from this effort. In 2012, the interaction of filamin A with α7nAChR was shown to be critical to Aβ42 's toxic signaling via α7nAChR, presenting a new drug target. The novel drug candidate simufilam disrupts the filamin A-α7nAChR interaction, reduces Aβ42 's high-affinity binding to α7nAChR, and suppresses Aβ42 's toxic signaling. Early clinical trials of simufilam showed improvements in experimental CSF biomarkers and indications of cognitive improvement in mild AD patients at 1 year. Simufilam is currently in phase 3 clinical trials as a disease-modifying treatment for AD.
Collapse
Affiliation(s)
| | - Zhe Pei
- Department of Molecular, Cellular and Biomedical Sciences, City University of New York School of Medicine, New York, New York, USA
| | - Hoau-Yan Wang
- Department of Molecular, Cellular and Biomedical Sciences, City University of New York School of Medicine, New York, New York, USA
- Department of Biology and Neuroscience, Graduate School of the City University of New York, New York, New York, USA
| |
Collapse
|
3
|
Viscarra F, Chrestia JF, Sanchez Y, Pérez EG, Biggin PC, Bouzat C, Bermudez I, López JJ. Side Groups Convert the α7 Nicotinic Receptor Agonist Ether Quinuclidine into a Type I Positive Allosteric Modulator. ACS Chem Neurosci 2023; 14:2876-2887. [PMID: 37535446 DOI: 10.1021/acschemneuro.3c00225] [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] [Indexed: 08/05/2023] Open
Abstract
The quinuclidine scaffold has been extensively used for the development of nicotinic acetylcholine receptor (nAChR) agonists, with hydrophobic substituents at position 3 of the quinuclidine framework providing selectivity for α7 nAChRs. In this study, six new ligands (4-9) containing a 3-(pyridin-3-yloxy)quinuclidine moiety (ether quinuclidine) were synthesized to gain a better understanding of the structural-functional properties of ether quinuclidines. To evaluate the pharmacological activity of these ligands, two-electrode voltage-clamp and single-channel recordings were performed. Only ligand 4 activated α7 nAChR. Ligands 5 and 7 had no effects on α7 nAChR, but ligands 6, 8, and 9 potentiated the currents evoked by ACh. Ligand 6 was the most potent and efficacious of the potentiating ligands, with an estimated EC50 for potentiation of 12.6 ± 3.32 μM and a maximal potentiation of EC20 ACh responses of 850 ± 120%. Ligand 6 increased the maximal ACh responses without changing the kinetics of the current responses. At the single-channel level, the potentiation exerted by ligand 6 was evidenced in the low micromolar concentration range by the appearance of prolonged bursts of channel openings. Furthermore, computational studies revealed the preference of ligand 6 for an intersubunit site in the transmembrane domain and highlighted some putative key interactions that explain the different profiles of the synthesized ligands. Notably, Met276 in the 15' position of the transmembrane domain 2 almost abolished the effects of ligand 6 when mutated to Leu. We conclude that ligand 6 is a novel type I positive allosteric modulator (PAM-I) of α7 nAChR.
Collapse
Affiliation(s)
- Franco Viscarra
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, U.K
- Structural Bioinformatics and Computational Biochemistry, Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, U.K
| | - Juan Facundo Chrestia
- Departamento de Biología, Bioquímica y Farmacia, Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Camino La Carrindanga Km 7, Bahía Blanca 8000, Argentina
| | - Yaima Sanchez
- Department of Organic Chemistry, Faculty of Chemistry, Universidad de Concepción, Edmundo Larenas 129, Concepción 4070371, Chile
| | - Edwin G Pérez
- Department of Organic Chemistry, Faculty of Chemistry and Pharmacy, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 7820436, Chile
| | - Philip C Biggin
- Structural Bioinformatics and Computational Biochemistry, Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, U.K
| | - Cecilia Bouzat
- Departamento de Biología, Bioquímica y Farmacia, Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Camino La Carrindanga Km 7, Bahía Blanca 8000, Argentina
| | - Isabel Bermudez
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, U.K
| | - Jhon J López
- Department of Organic Chemistry, Faculty of Chemistry, Universidad de Concepción, Edmundo Larenas 129, Concepción 4070371, Chile
| |
Collapse
|
4
|
Terry AV, Callahan PM. α7 nicotinic acetylcholine receptors as therapeutic targets in schizophrenia: Update on animal and clinical studies and strategies for the future. Neuropharmacology 2020; 170:108053. [PMID: 32188568 DOI: 10.1016/j.neuropharm.2020.108053] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 03/10/2020] [Accepted: 03/11/2020] [Indexed: 10/24/2022]
Abstract
Schizophrenia is a devastating mental illness and its effective treatment is among the most challenging issues in psychiatry. The symptoms of schizophrenia are heterogeneous ranging from positive symptoms (e.g., delusions, hallucinations) to negative symptoms (e.g., anhedonia, social withdrawal) to cognitive dysfunction. Antipsychotics are effective at ameliorating positive symptoms in some patients; however, they are not reliably effective at improving the negative symptoms or cognitive impairments. The inability to address the cognitive impairments is a particular concern since they have the greatest long-term impact on functional outcomes. While decades of research have been devoted to the development of pro-cognitive agents for schizophrenia, to date, no drug has been approved for clinical use. Converging behavioral, neurobiological, and genetic evidence led to the identification of the α7-nicotinic acetylcholine receptor (α7-nAChR) as a therapeutic target several years ago and there is now extensive preclinical evidence that α7-nAChR ligands have pro-cognitive effects and other properties that should be beneficial to schizophrenia patients. However, like the other pro-cognitive strategies, no α7-nAChR ligand has been approved for clinical use in schizophrenia thus far. In this review, several topics are discussed that may impact the success of α7-nAChR ligands as pro-cognitive agents for schizophrenia including the translational value of the animal models used, clinical trial design limitations, confounding effects of polypharmacy, dose-effect relationships, and chronic versus intermittent dosing considerations. Determining the most optimal pharmacologic strategy at α7-nAChRs: agonist, positive allosteric modulator, or potentially even receptor antagonist is also discussed. article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.
Collapse
Affiliation(s)
- Alvin V Terry
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia; Small Animal Behavior Core, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia.
| | - Patrick M Callahan
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia; Small Animal Behavior Core, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia
| |
Collapse
|
5
|
Barnes TR, Drake R, Paton C, Cooper SJ, Deakin B, Ferrier IN, Gregory CJ, Haddad PM, Howes OD, Jones I, Joyce EM, Lewis S, Lingford-Hughes A, MacCabe JH, Owens DC, Patel MX, Sinclair JM, Stone JM, Talbot PS, Upthegrove R, Wieck A, Yung AR. Evidence-based guidelines for the pharmacological treatment of schizophrenia: Updated recommendations from the British Association for Psychopharmacology. J Psychopharmacol 2020; 34:3-78. [PMID: 31829775 DOI: 10.1177/0269881119889296] [Citation(s) in RCA: 142] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
These updated guidelines from the British Association for Psychopharmacology replace the original version published in 2011. They address the scope and targets of pharmacological treatment for schizophrenia. A consensus meeting was held in 2017, involving experts in schizophrenia and its treatment. They were asked to review key areas and consider the strength of the evidence on the risk-benefit balance of pharmacological interventions and the clinical implications, with an emphasis on meta-analyses, systematic reviews and randomised controlled trials where available, plus updates on current clinical practice. The guidelines cover the pharmacological management and treatment of schizophrenia across the various stages of the illness, including first-episode, relapse prevention, and illness that has proved refractory to standard treatment. It is hoped that the practice recommendations presented will support clinical decision making for practitioners, serve as a source of information for patients and carers, and inform quality improvement.
Collapse
Affiliation(s)
- Thomas Re Barnes
- Emeritus Professor of Clinical Psychiatry, Division of Psychiatry, Imperial College London, and Joint-head of the Prescribing Observatory for Mental Health, Centre for Quality Improvement, Royal College of Psychiatrists, London, UK
| | - Richard Drake
- Clinical Lead for Mental Health in Working Age Adults, Health Innovation Manchester, University of Manchester and Greater Manchester Mental Health NHS Foundation Trust, Manchester, UK
| | - Carol Paton
- Joint-head of the Prescribing Observatory for Mental Health, Centre for Quality Improvement, Royal College of Psychiatrists, London, UK
| | - Stephen J Cooper
- Emeritus Professor of Psychiatry, School of Medicine, Queen's University Belfast, Belfast, UK
| | - Bill Deakin
- Professor of Psychiatry, Neuroscience & Psychiatry Unit, University of Manchester and Greater Manchester Mental Health NHS Foundation Trust, Manchester, UK
| | - I Nicol Ferrier
- Emeritus Professor of Psychiatry, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Catherine J Gregory
- Honorary Clinical Research Fellow, University of Manchester and Higher Trainee in Child and Adolescent Psychiatry, Manchester University NHS Foundation Trust, Manchester, UK
| | - Peter M Haddad
- Honorary Professor of Psychiatry, Division of Psychology and Mental Health, University of Manchester, UK and Senior Consultant Psychiatrist, Department of Psychiatry, Hamad Medical Corporation, Doha, Qatar
| | - Oliver D Howes
- Professor of Molecular Psychiatry, Imperial College London and Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Ian Jones
- Professor of Psychiatry and Director, National Centre of Mental Health, Cardiff University, Cardiff, UK
| | - Eileen M Joyce
- Professor of Neuropsychiatry, UCL Queen Square Institute of Neurology, London, UK
| | - Shôn Lewis
- Professor of Adult Psychiatry, Faculty of Biology, Medicine and Health, The University of Manchester, UK, and Mental Health Academic Lead, Health Innovation Manchester, Manchester, UK
| | - Anne Lingford-Hughes
- Professor of Addiction Biology and Honorary Consultant Psychiatrist, Imperial College London and Central North West London NHS Foundation Trust, London, UK
| | - James H MacCabe
- Professor of Epidemiology and Therapeutics, Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, and Honorary Consultant Psychiatrist, National Psychosis Service, South London and Maudsley NHS Foundation Trust, Beckenham, UK
| | - David Cunningham Owens
- Professor of Clinical Psychiatry, University of Edinburgh. Honorary Consultant Psychiatrist, Royal Edinburgh Hospital, Edinburgh, UK
| | - Maxine X Patel
- Honorary Clinical Senior Lecturer, King's College London, Institute of Psychiatry, Psychology and Neuroscience and Consultant Psychiatrist, Oxleas NHS Foundation Trust, London, UK
| | - Julia Ma Sinclair
- Professor of Addiction Psychiatry, Faculty of Medicine, University of Southampton, Southampton, UK
| | - James M Stone
- Clinical Senior Lecturer and Honorary Consultant Psychiatrist, King's College London, Institute of Psychiatry, Psychology and Neuroscience and South London and Maudsley NHS Trust, London, UK
| | - Peter S Talbot
- Senior Lecturer and Honorary Consultant Psychiatrist, University of Manchester and Greater Manchester Mental Health NHS Foundation Trust, Manchester, UK
| | - Rachel Upthegrove
- Professor of Psychiatry and Youth Mental Health, University of Birmingham and Consultant Psychiatrist, Birmingham Early Intervention Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Angelika Wieck
- Honorary Consultant in Perinatal Psychiatry, Greater Manchester Mental Health NHS Foundation Trust, Manchester, UK
| | - Alison R Yung
- Professor of Psychiatry, University of Manchester, School of Health Sciences, Manchester, UK and Centre for Youth Mental Health, University of Melbourne, Australia, and Honorary Consultant Psychiatrist, Greater Manchester Mental Health NHS Foundation Trust, Manchester, UK
| |
Collapse
|
6
|
Tregellas JR, Wylie KP. Alpha7 Nicotinic Receptors as Therapeutic Targets in Schizophrenia. Nicotine Tob Res 2019; 21:349-356. [PMID: 30137618 DOI: 10.1093/ntr/nty034] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 03/09/2018] [Indexed: 12/12/2022]
Abstract
While current treatments for schizophrenia often provide much relief for positive symptoms such as hallucinations, other symptoms, particularly cognitive deficits, persist and contribute to substantial suffering and reduced quality of life for patients. In searching for novel therapeutic avenues to treat cognitive deficits in schizophrenia, recent work is exploring nicotinic receptor neurobiology. Supported by a large body of evidence, with contributions from studies of smoking behaviors, genetics, receptor distribution and function, animal models and nicotinic effects on illness symptoms, the alpha7 nicotinic receptor has emerged as a potential therapeutic target. Despite promise in early clinical trials, however, no drug targeting nicotinic systems has succeeded in larger phase 3 trials. Following a brief review of nicotinic receptor biology and the evidence that has led to pursuit of alpha7 nicotinic agonism as a therapeutic strategy, this review will provide an update on the status of recent trials, discuss potential issues that may have contributed to negative outcomes, and point to new directions and promising advances in developing alpha7 nicotinic receptor-based treatment for cognitive symptoms in schizophrenia. IMPLICATIONS By examining alpha7 nicotinic receptor biology and recent efforts to target the receptor in clinical trials, it is hoped that investigators will be motivated to explore novel, promising directions focusing on the receptor as a strategy to treat cognitive symptoms in schizophrenia.
Collapse
Affiliation(s)
- Jason R Tregellas
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO.,Research Service, Denver VA Medical Center, Denver, CO
| | - Korey P Wylie
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO.,Research Service, Denver VA Medical Center, Denver, CO
| |
Collapse
|
7
|
Jankowska A, Satała G, Partyka A, Wesołowska A, Bojarski AJ, Pawłowski M, Chłoń-Rzepa G. Discovery and Development of Non-Dopaminergic Agents for the Treatment of Schizophrenia: Overview of the Preclinical and Early Clinical Studies. Curr Med Chem 2019; 26:4885-4913. [PMID: 31291870 DOI: 10.2174/0929867326666190710172002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/11/2019] [Accepted: 06/14/2019] [Indexed: 02/05/2023]
Abstract
Schizophrenia is a chronic psychiatric disorder that affects about 1 in 100 people around the world and results in persistent emotional and cognitive impairments. Untreated schizophrenia leads to deterioration in quality of life and premature death. Although the clinical efficacy of dopamine D2 receptor antagonists against positive symptoms of schizophrenia supports the dopamine hypothesis of the disease, the resistance of negative and cognitive symptoms to these drugs implicates other systems in its pathophysiology. Many studies suggest that abnormalities in glutamate homeostasis may contribute to all three groups of schizophrenia symptoms. Scientific considerations also include disorders of gamma-aminobutyric acid-ergic and serotonergic neurotransmissions as well as the role of the immune system. The purpose of this review is to update the most recent reports on the discovery and development of non-dopaminergic agents that may reduce positive, negative, and cognitive symptoms of schizophrenia, and may be alternative to currently used antipsychotics. This review collects the chemical structures of representative compounds targeting metabotropic glutamate receptor, gamma-aminobutyric acid type A receptor, alpha 7 nicotinic acetylcholine receptor, glycine transporter type 1 and glycogen synthase kinase 3 as well as results of in vitro and in vivo studies indicating their efficacy in schizophrenia. Results of clinical trials assessing the safety and efficacy of the tested compounds have also been presented. Finally, attention has been paid to multifunctional ligands with serotonin receptor affinity or phosphodiesterase inhibitory activity as novel strategies in the search for dedicated medicines for patients with schizophrenia.
Collapse
Affiliation(s)
- Agnieszka Jankowska
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland
| | - Grzegorz Satała
- Department of Medicinal Chemistry, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343 Krakow, Poland
| | - Anna Partyka
- Department of Clinical Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland
| | - Anna Wesołowska
- Department of Clinical Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland
| | - Andrzej J Bojarski
- Department of Medicinal Chemistry, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343 Krakow, Poland
| | - Maciej Pawłowski
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland
| | - Grażyna Chłoń-Rzepa
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland
| |
Collapse
|
8
|
Geerts H, Barrett JE. Neuronal Circuit-Based Computer Modeling as a Phenotypic Strategy for CNS R&D. Front Neurosci 2019; 13:723. [PMID: 31379482 PMCID: PMC6646593 DOI: 10.3389/fnins.2019.00723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 06/28/2019] [Indexed: 12/13/2022] Open
Abstract
With the success rate of drugs for CNS indications at an all-time low, new approaches are needed to turn the tide of failed clinical trials. This paper reviews the history of CNS drug Discovery over the last 60 years and proposes a new paradigm based on the lessons learned. The initial wave of successful therapeutics discovered using careful clinical observations was followed by an emphasis on a phenotypic target-agnostic approach, often leading to successful drugs with a rich pharmacology. The subsequent introduction of molecular biology and the focus on a target-driven strategy has largely dominated drug discovery efforts over the last 30 years, but has not increased the probability of success, because these highly selective molecules are unlikely to address the complex pathological phenotypes of most CNS disorders. In many cases, reliance on preclinical animal models has lacked robust translational power. We argue that Quantitative Systems Pharmacology (QSP), a mechanism-based computer model of biological processes informed by preclinical knowledge and enhanced by neuroimaging and clinical data could be a new powerful knowledge generator engine and paradigm for rational polypharmacy. Progress in the academic discipline of computational neurosciences, allows one to model the effect of pathology and therapeutic interventions on neuronal circuit firing activity that can relate to clinical phenotypes, driven by complex properties of specific brain region activation states. The model is validated by optimizing the correlation between relevant emergent properties of these neuronal circuits and historical clinical and imaging datasets. A rationally designed polypharmacy target profile will be discovered using reverse engineering and sensitivity analysis. Small molecules will be identified using a combination of Artificial Intelligence methods and computational modeling, tested subsequently in heterologous cellular systems with human targets. Animal models will be used to establish target engagement and for ADME-Tox, with the QSP approach complemented by in vivo preclinical models that can be further refined to increase predictive validity. The QSP platform can also mitigate the variability in clinical trials with the concept of virtual patients. Because the QSP platform integrates knowledge from a wide variety of sources in an actionable simulation, it offers the possibility of substantially improving the success rate of CNS R&D programs while, at the same time, reducing both cost and the number of animals.
Collapse
Affiliation(s)
- Hugo Geerts
- In Silico Biosciences, Inc., Berwyn, IL, United States
| | - James E Barrett
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| |
Collapse
|
9
|
Designing selective modulators for the nicotinic receptor subtypes: challenges and opportunities. Future Med Chem 2018; 10:433-459. [PMID: 29451400 DOI: 10.4155/fmc-2017-0169] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nicotinic receptors are membrane proteins involved in several physiological processes. They are considered suitable drug targets for various CNS disorders or conditions, as shown by the large number of compounds which have entered clinical trials. In recent years, nonconventional agonists have been discovered: positive allosteric modulators, allosteric agonists, site-specific agonists and silent desensitizers are compounds able to modulate the receptor interacting at sites different from the orthodox one, or to desensitize the receptor without prior opening. While these new findings can further complicate the pharmacology of these proteins and the design and optimization of ligands, they undoubtedly offer new opportunities to find drugs for the many therapeutic indications involving nicotinic receptors.
Collapse
|