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Nirogi R, Grandhi VR, Medapati R, Ganuga N, Abraham R, Thentu JB, Palacharla VRC, Petlu S, Srirangavaram M, Subramanian R, Ravella SR, Gagginapally SR, Benade V, Jayarajan P, Mohammed AR. Usmarapride (SUVN-D4010), a 5-HT4 receptor partial agonist for the potential treatment of Alzheimer's disease: Behavioural, neurochemical and pharmacological profiling. Eur J Pharmacol 2023; 947:175625. [PMID: 36997046 DOI: 10.1016/j.ejphar.2023.175625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 02/24/2023] [Accepted: 02/24/2023] [Indexed: 03/30/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder which affects cognitive functions with negative impact on day to day activities and an ultimate loss of independent living. Current standard of care (SOC) for AD, viz. donepezil, rivastigmine, galantamine, memantine etc. either alone or in combination show modest efficacy without changing the course of the disease. On prolonged treatment, side effects are more common with an eventual loss of efficacy. Aducanumab, a monoclonal antibody is a disease modifying therapeutic agent targeting the toxic amyloid beta (Aβ) proteins for its clearance. However, it is found to have only modest efficacy in AD patients and its approval by FDA is controversial. Alternate, effective and safe therapeutics are need of the hour, as AD cases are expected to be doubled by 2050. Recently, 5-HT4 receptors have been envisioned as target for alleviating AD associated cognitive impairment with potential disease modifying ability impacting disease progression. Usmarapride is a 5-HT4 receptor partial agonist, being developed for the possible treatment of AD with symptomatic and disease modifying potential. Usmarapride demonstrated promising effects in ameliorating cognitive deficits in diverse animal models of episodic, working, social, and emotional memories. Usmarapride produced elevation in cortical acetylcholine in rats. Furthermore, usmarapride increased levels of soluble amyloid precursor protein alpha, a potential mechanism to reverse toxic Aβ peptide pathology. Usmarapride also potentiated the pharmacological effects of donepezil in animal models. To conclude, usmarapride may be a promising intervention for alleviating the cognitive dysfunction in AD patients with disease modifying potential.
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Cho Y, Bae HG, Okun E, Arumugam TV, Jo DG. Physiology and pharmacology of amyloid precursor protein. Pharmacol Ther 2022; 235:108122. [PMID: 35114285 DOI: 10.1016/j.pharmthera.2022.108122] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/17/2022] [Accepted: 01/25/2022] [Indexed: 02/06/2023]
Abstract
Amyloid precursor protein (APP) is an evolutionarily conserved transmembrane protein and a well-characterized precursor protein of amyloid-beta (Aβ) peptides, which accumulate in the brains of individuals with Alzheimer's disease (AD)-related pathologies. Aβ has been extensively investigated since the amyloid hypothesis in AD was proposed. Besides Aβ, previous studies on APP and its proteolytic cleavage products have suggested their diverse pathological and physiological functions. However, their roles still have not been thoroughly understood. In this review, we extensively discuss the evolutionarily-conserved biology of APP, including its structure and processing pathway, as well as recent findings on the physiological roles of APP and its fragments in the central nervous system and peripheral nervous system. We have also elaborated upon the current status of APP-targeted therapeutic approaches for AD treatment by discussing inhibitors of several proteases participating in APP processing, including α-, β-, and γ-secretases. Finally, we have highlighted the future perspectives pertaining to further research and the potential clinical role of APP.
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Affiliation(s)
- Yoonsuk Cho
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea
| | - Han-Gyu Bae
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea
| | - Eitan Okun
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan 5290002, Israel; The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel; The Pauld Feder Laboratory on Alzheimer's Disease Research, Israel
| | - Thiruma V Arumugam
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea; School of Life Sciences, La Trobe University, Bundoora, Victoria, Australia.
| | - Dong-Gyu Jo
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea; Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 06351, South Korea; Biomedical Institute for Convergence, Sungkyunkwan University, Suwon 16419, South Korea.
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3
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Zong B, Yu F, Zhang X, Zhao W, Sun P, Li S, Li L. Understanding How Physical Exercise Improves Alzheimer’s Disease: Cholinergic and Monoaminergic Systems. Front Aging Neurosci 2022; 14:869507. [PMID: 35663578 PMCID: PMC9158463 DOI: 10.3389/fnagi.2022.869507] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 04/14/2022] [Indexed: 01/11/2023] Open
Abstract
Alzheimer’s disease (AD) is an age-related neurodegenerative disorder, characterized by the accumulation of proteinaceous aggregates and neurofibrillary lesions composed of β-amyloid (Aβ) peptide and hyperphosphorylated microtubule-associated protein tau, respectively. It has long been known that dysregulation of cholinergic and monoaminergic (i.e., dopaminergic, serotoninergic, and noradrenergic) systems is involved in the pathogenesis of AD. Abnormalities in neuronal activity, neurotransmitter signaling input, and receptor function exaggerate Aβ deposition and tau hyperphosphorylation. Maintenance of normal neurotransmission is essential to halt AD progression. Most neurotransmitters and neurotransmitter-related drugs modulate the pathology of AD and improve cognitive function through G protein-coupled receptors (GPCRs). Exercise therapies provide an important alternative or adjunctive intervention for AD. Cumulative evidence indicates that exercise can prevent multiple pathological features found in AD and improve cognitive function through delaying the degeneration of cholinergic and monoaminergic neurons; increasing levels of acetylcholine, norepinephrine, serotonin, and dopamine; and modulating the activity of certain neurotransmitter-related GPCRs. Emerging insights into the mechanistic links among exercise, the neurotransmitter system, and AD highlight the potential of this intervention as a therapeutic approach for AD.
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Affiliation(s)
- Boyi Zong
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- College of Physical Education and Health, East China Normal University, Shanghai, China
| | - Fengzhi Yu
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- College of Physical Education and Health, East China Normal University, Shanghai, China
| | - Xiaoyou Zhang
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- College of Physical Education and Health, East China Normal University, Shanghai, China
| | - Wenrui Zhao
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- College of Physical Education and Health, East China Normal University, Shanghai, China
| | - Peng Sun
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- College of Physical Education and Health, East China Normal University, Shanghai, China
| | - Shichang Li
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- College of Physical Education and Health, East China Normal University, Shanghai, China
| | - Lin Li
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- College of Physical Education and Health, East China Normal University, Shanghai, China
- *Correspondence: Lin Li,
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4
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How nano-engineered delivery systems can help marketed and repurposed drugs in Alzheimer’s disease treatment? Drug Discov Today 2022; 27:1575-1589. [DOI: 10.1016/j.drudis.2022.02.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 01/11/2022] [Accepted: 02/22/2022] [Indexed: 11/24/2022]
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5
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Hashemi-Firouzi N, Shahidi S, Soleimani Asl S. Chronic stimulation of the serotonergic 5-HT4 receptor modulates amyloid-beta-related impairments in synaptic plasticity and memory deficits in male rats. Brain Res 2021; 1773:147701. [PMID: 34695393 DOI: 10.1016/j.brainres.2021.147701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 10/14/2021] [Accepted: 10/18/2021] [Indexed: 01/25/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease characterized by memory decline and impaired hippocampal synaptic plasticity. The serotonin 5-HT4 receptor is involved in learning and memory processes. This study explored the effects of chronic stimulation of 5-HT4R on cognition, memory, long-term potentiation (LTP), paired-pulse ratio (PPR), and neuronal apoptosis in a rat model of amyloid-beta (Aβ)-induced AD. Thirty-five male Wistar rats were randomly divided into three groups as follows: the sham, Aβ, and Aβ + BIMU8 groups. Aβ (6 µg/µl) was administrated by intracerebroventricular (icv) injection. The animals were treated with BIMU8 (1 μg/μL, ICV) as a 5-HT4R agonist for 30 days. Memory and behavioral changes were assessed by the passive avoidance learning, novel object recognition, open field, and elevated plus maze tests. Hippocampal synaptic plasticity was evaluated in the dentate gyrus (DG) in response to the stimulation applied to the perforant pathway. Furthermore, neuronal apoptosis was measured in the hippocampus. Data were analyzed by SPSS version 19 using one-way ANOVA, followed by Tukey's post hoc test. Aβ induced memory deficits and neuronal loss and inhibited LTP induction. Aβ also increased the normalized PPR. BIMU8 enhanced the slope of the field excitatory postsynaptic potential in LTP and improved cognition behavior. Paired-pulse inhibition or facilitation was not affected by LTP induction in Aβ animals receiving the BIMU8. It can be concluded that the stimulation of the 5-HT4 receptor modulated the Aβ-induced cognition and memory deficits, probably via a decrease in the hippocampal apoptotic neurons and an improvement in the hippocampal synaptic functions without involving its inhibitory interneurons.
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Affiliation(s)
- Nasrin Hashemi-Firouzi
- Department of Physiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Siamak Shahidi
- Department of Physiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Sara Soleimani Asl
- Anatomy Department, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
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6
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Role of Receptors in Relation to Plaques and Tangles in Alzheimer's Disease Pathology. Int J Mol Sci 2021; 22:ijms222312987. [PMID: 34884789 PMCID: PMC8657621 DOI: 10.3390/ijms222312987] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/26/2021] [Accepted: 11/28/2021] [Indexed: 12/23/2022] Open
Abstract
Despite the identification of Aβ plaques and NFTs as biomarkers for Alzheimer’s disease (AD) pathology, therapeutic interventions remain elusive, with neither an absolute prophylactic nor a curative medication available to impede the progression of AD presently available. Current approaches focus on symptomatic treatments to maintain AD patients’ mental stability and behavioral symptoms by decreasing neuronal degeneration; however, the complexity of AD pathology requires a wide range of therapeutic approaches for both preventive and curative treatments. In this regard, this review summarizes the role of receptors as a potential target for treating AD and focuses on the path of major receptors which are responsible for AD progression. This review gives an overall idea centering on major receptors, their agonist and antagonist and future prospects of viral mimicry in AD pathology. This article aims to provide researchers and developers a comprehensive idea about the different receptors involved in AD pathogenesis that may lead to finding a new therapeutic strategy to treat AD.
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7
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Memory Disorders Related to Hippocampal Function: The Interest of 5-HT 4Rs Targeting. Int J Mol Sci 2021; 22:ijms222112082. [PMID: 34769511 PMCID: PMC8584667 DOI: 10.3390/ijms222112082] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/30/2021] [Accepted: 11/03/2021] [Indexed: 11/16/2022] Open
Abstract
The hippocampus has long been considered as a key structure for memory processes. Multilevel alterations of hippocampal function have been identified as a common denominator of memory impairments in a number of psychiatric and neurodegenerative diseases. For many years, the glutamatergic and cholinergic systems have been the main targets of therapeutic treatments against these symptoms. However, the high rate of drug development failures has left memory impairments on the sideline of current therapeutic strategies. This underscores the urgent need to focus on new therapeutic targets for memory disorders, such as type 4 serotonin receptors (5-HT4Rs). Ever since the discovery of their expression in the hippocampus, 5-HT4Rs have gained growing interest for potential use in the treatment of learning and memory impairments. To date, much of the researched information gathered by scientists from both animal models and humans converge on pro-mnesic and anti-amnesic properties of 5-HT4Rs activation, although the mechanisms at work require more work to be fully understood. This review addresses a fundamental, yet poorly understood set of evidence of the potential of 5-HT4Rs to re-establish or limit hippocampal alterations related to neurological diseases. Most importantly, the potential of 5-HT4Rs is translated by refining hypotheses regarding the benefits of their activation in memory disorders at the hippocampal level.
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8
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Nirogi R, Mohammed AR, Shinde AK, Gagginapally SR, Kancharla DM, Ravella SR, Bogaraju N, Middekadi VR, Subramanian R, Palacharla RC, Benade V, Muddana N, Abraham R, Medapati RB, Thentu JB, Mekala VR, Petlu S, Lingavarapu BB, Yarra S, Kagita N, Goyal VK, Pandey SK, Jasti V. Discovery and Preclinical Characterization of Usmarapride (SUVN-D4010): A Potent, Selective 5-HT 4 Receptor Partial Agonist for the Treatment of Cognitive Deficits Associated with Alzheimer's Disease. J Med Chem 2021; 64:10641-10665. [PMID: 34251799 DOI: 10.1021/acs.jmedchem.1c00703] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of oxadiazole derivatives were synthesized and evaluated as 5-hydroxytryptamine-4 receptor (5-HT4R) partial agonists for the treatment of cognitive deficits associated with Alzheimer's disease. Starting from a reported 5-HT4R antagonist, a systematic structure-activity relationship was conducted, which led to the discovery of potent and selective 5-HT4R partial agonist 1-isopropyl-3-{5-[1-(3-methoxypropyl) piperidin-4-yl]-[1,3,4]oxadiazol-2-yl}-1H-indazole oxalate (Usmarapride, 12l). It showed balanced physicochemical-pharmacokinetic properties with robust nonclinical efficacy in cognition models. It also showed disease-modifying potential, as it increased neuroprotective soluble amyloid precursor protein alpha levels, and dose-dependent target engagement and correlation of efficacy with oral exposures. Phase 1 clinical studies have been completed and projected efficacious concentration was achieved without any major safety concerns. Phase 2 enabling long-term safety studies have been completed with no concerns for further development.
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Affiliation(s)
- Ramakrishna Nirogi
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Abdul Rasheed Mohammed
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Anil Karbhari Shinde
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | | | | | - Srinivasa Rao Ravella
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Narsimha Bogaraju
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Vanaja Reddy Middekadi
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Ramkumar Subramanian
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | | | - Vijay Benade
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Nageswararao Muddana
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Renny Abraham
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Rajesh Babu Medapati
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Jagadeesh Babu Thentu
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Venkat Reddy Mekala
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Surendra Petlu
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Bujji Babu Lingavarapu
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Sivasekhar Yarra
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Narendra Kagita
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Vinod Kumar Goyal
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Santosh Kumar Pandey
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
| | - Venkat Jasti
- Suven Life Sciences Limited, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500 034, India
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9
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Murphy SE, de Cates AN, Gillespie AL, Godlewska BR, Scaife JC, Wright LC, Cowen PJ, Harmer CJ. Translating the promise of 5HT 4 receptor agonists for the treatment of depression. Psychol Med 2021; 51:1111-1120. [PMID: 32241310 PMCID: PMC8188527 DOI: 10.1017/s0033291720000604] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 02/21/2020] [Accepted: 02/28/2020] [Indexed: 12/11/2022]
Abstract
Animal experimental studies suggest that 5-HT4 receptor activation holds promise as a novel target for the treatment of depression and cognitive impairment. 5-HT4 receptors are post-synaptic receptors that are located in striatal and limbic areas known to be involved in cognition and mood. Consistent with this, 5-HT4 receptor agonists produce rapid antidepressant effects in a number of animal models of depression, and pro-cognitive effects in tasks of learning and memory. These effects are accompanied by molecular changes, such as the increased expression of neuroplasticity-related proteins that are typical of clinically useful antidepressant drugs. Intriguingly, these antidepressant-like effects have a fast onset of their action, raising the possibility that 5-HT4 receptor agonists may be a particularly useful augmentation strategy in the early stages of SSRI treatment. Until recently, the translation of these effects to humans has been challenging. Here, we review the evidence from animal studies that the 5-HT4 receptor is a promising target for the treatment of depression and cognitive disorders, and outline a potential pathway for the efficient and cost-effective translation of these effects into humans and, ultimately, to the clinic.
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Affiliation(s)
- Susannah E Murphy
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Angharad N de Cates
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Amy L Gillespie
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Beata R Godlewska
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Jessica C Scaife
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Lucy C Wright
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Philip J Cowen
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Catherine J Harmer
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
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Development of Novel Potential Pleiotropic Compounds of Interest in Alzheimer's Disease Treatment through Rigidification Strategy. Molecules 2021; 26:molecules26092536. [PMID: 33926141 PMCID: PMC8123621 DOI: 10.3390/molecules26092536] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/06/2021] [Accepted: 04/20/2021] [Indexed: 12/17/2022] Open
Abstract
The development of Multi-Target Directed Ligand is of clear interest for the treatment of multifactorial pathology such as Alzheimer’s disease (AD). In this context, acetylcholinesterase (AChE) inhibitors have been modulated in order to generate novel pleiotropic compounds targeting a second protein of therapeutic interest in AD. Among them, donecopride was the first example of a dual acetylcholinesterase inhibitor and 5-HT4 receptor agonist. In order to explore the structural diversity around this preclinical candidate we have explored the preparation of novel constrained analogs through late-stage rigidification strategy. A series of phenylpyrazoles was prepared in a late-stage functionalization process and all compounds were evaluated in vitro towards AChE and 5-HTRs. A docking study was performed in order to better explain the observed SAR towards AChE, 5-HT4R and 5-HT6R and this study led to the description of novel ligand targeting both AChE and 5-HT6R.
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Machine learning classifies predictive kinematic features in a mouse model of neurodegeneration. Sci Rep 2021; 11:3950. [PMID: 33597593 PMCID: PMC7889656 DOI: 10.1038/s41598-021-82694-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 01/21/2021] [Indexed: 01/31/2023] Open
Abstract
Motor deficits are observed in Alzheimer's disease (AD) prior to the appearance of cognitive symptoms. To investigate the role of amyloid proteins in gait disturbances, we characterized locomotion in APP-overexpressing transgenic J20 mice. We used three-dimensional motion capture to characterize quadrupedal locomotion on a treadmill in J20 and wild-type mice. Sixteen J20 mice and fifteen wild-type mice were studied at two ages (4- and 13-month). A random forest (RF) classification algorithm discriminated between the genotypes within each age group using a leave-one-out cross-validation. The balanced accuracy of the RF classification was 92.3 ± 5.2% and 93.3 ± 4.5% as well as False Negative Rate (FNR) of 0.0 ± 0.0% and 0.0 ± 0.0% for the 4-month and 13-month groups, respectively. Feature ranking algorithms identified kinematic features that when considered simultaneously, achieved high genotype classification accuracy. The identified features demonstrated an age-specific kinematic profile of the impact of APP-overexpression. Trunk tilt and unstable hip movement patterns were important in classifying the 4-month J20 mice, whereas patterns of shoulder and iliac crest movement were critical for classifying 13-month J20 mice. Examining multiple kinematic features of gait simultaneously could also be developed to classify motor disorders in humans.
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Alarcón-Espósito J, Mallea M, Rodríguez-Lavado J. From Hybrids to New Scaffolds: The Latest Medicinal Chemistry Goals in Multi-target Directed Ligands for Alzheimer's Disease. Curr Neuropharmacol 2021; 19:832-867. [PMID: 32928087 PMCID: PMC8686302 DOI: 10.2174/1570159x18666200914155951] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/13/2020] [Accepted: 08/28/2020] [Indexed: 11/22/2022] Open
Abstract
Alzheimer's disease (AD) is a chronic, progressive, and fatal neurodegenerative disorder affecting cognition, behavior, and function, being one of the most common causes of mental deterioration in elderly people. Once thought as being just developed because of β amyloid depositions or neurofibrillary Tau tangles, during the last decades, numerous AD-related targets have been established, the multifactorial nature of AD became evident. In this context, the one drug-one target paradigm has resulted in being inefficient in facing AD and other disorders with complex etiology, opening the field for the emergence of the multitarget approach. In this review, we highlight the recent advances within this area, emphasizing in hybridization tools of well-known chemical scaffolds endowed with pharmacological properties concerning AD, such as curcumin-, resveratrol-, chromone- and indole-. We focus mainly on well established and incipient AD therapeutic targets, AChE, BuChE, MAOs, β-amyloid deposition, 5-HT4 and Serotonin transporter, with the aim to shed light about new insights in the AD multitarget therapy.
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Affiliation(s)
- Jazmín Alarcón-Espósito
- Departamento de Quimica Organica y Fisicoquimica, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Olivos 1007, Independencia, Santiago, Chile
| | - Michael Mallea
- Departamento de Quimica Organica y Fisicoquimica, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Olivos 1007, Independencia, Santiago, Chile
| | - Julio Rodríguez-Lavado
- Departamento de Quimica Organica y Fisicoquimica, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Olivos 1007, Independencia, Santiago, Chile
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13
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Abstract
BACKGROUND 5-HT4 receptor stimulation has pro-cognitive and antidepressant-like effects in animal experimental studies; however, this pharmacological approach has not yet been tested in humans. Here we used the 5-HT4 receptor partial agonist prucalopride to assess the translatability of these effects and characterise, for the first time, the consequences of 5-HT4 receptor activation on human cognition and emotion. METHODS Forty one healthy volunteers were randomised, double-blind, to a single dose of prucalopride (1 mg) or placebo in a parallel group design. They completed a battery of cognitive tests measuring learning and memory, emotional processing and reward sensitivity. RESULTS Prucalopride increased recall of words in a verbal learning task, increased the accuracy of recall and recognition of words in an incidental emotional memory task and increased the probability of choosing a symbol associated with a high likelihood of reward or absence of loss in a probabilistic instrumental learning task. Thus acute prucalopride produced pro-cognitive effects in healthy volunteers across three separate tasks. CONCLUSIONS These findings are a translation of the memory enhancing effects of 5-HT4 receptor agonism seen in animal studies, and lend weight to the idea that the 5-HT4 receptor could be an innovative target for the treatment of cognitive deficits associated with depression and other neuropsychiatric disorders. Contrary to the effects reported in animal models, prucalopride did not reveal an antidepressant profile in human measures of emotional processing.
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Affiliation(s)
- Susannah E Murphy
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Lucy C Wright
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Michael Browning
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Philip J Cowen
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Catherine J Harmer
- University Department of Psychiatry, Warneford Hospital, University of Oxford, OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
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14
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Lanthier C, Payan H, Liparulo I, Hatat B, Lecoutey C, Since M, Davis A, Bergamini C, Claeysen S, Dallemagne P, Bolognesi ML, Rochais C. Novel multi target-directed ligands targeting 5-HT4 receptors with in cellulo antioxidant properties as promising leads in Alzheimer's disease. Eur J Med Chem 2019; 182:111596. [DOI: 10.1016/j.ejmech.2019.111596] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/19/2019] [Accepted: 08/05/2019] [Indexed: 12/12/2022]
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15
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Daniali M, Nikfar S, Abdollahi M. An overview of the efficacy and safety of prucalopride for the treatment of chronic idiopathic constipation. Expert Opin Pharmacother 2019; 20:2073-2080. [DOI: 10.1080/14656566.2019.1668927] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Marzieh Daniali
- Toxicology and Diseases Group (TDG), Pharmaceutical Sciences Research Center (PSRC), The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Shekoufeh Nikfar
- Evidence-Based Evaluation of Cost-Effectiveness and Clinical Outcomes Group, Pharmaceutical Sciences Research Center (PSRC), and the Pharmaceutical Management and Economics Research Center (PMERC), The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
- Department of Pharmacoeconomics and Pharmaceutical Administration, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Abdollahi
- Toxicology and Diseases Group (TDG), Pharmaceutical Sciences Research Center (PSRC), The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
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16
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Nyarko JNK, Quartey MO, Baker GB, Mousseau DD. Can Animal Models Inform on the Relationship between Depression and Alzheimer Disease? CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 2019; 64:18-29. [PMID: 29685068 PMCID: PMC6364140 DOI: 10.1177/0706743718772514] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The focus on the β-amyloid (Aβ) peptide in clinical Alzheimer disease (AD) as well as in animal models of AD has perhaps biased our understanding of what contributes to the heterogeneity in disease onset and progression. Part of this heterogeneity could reflect the various neuropsychiatric risk factors that present with common symptomatology and can predispose the brain to AD-like changes. One such risk factor is depression. Animal models, particularly mouse models carrying variants of AD-related gene(s), many of which lead to an accumulation of Aβ, suggest that a fundamental shift in depression-related monoaminergic systems (including serotonin and noradrenaline) is a strong indicator of the altered cellular function associated with the earlier(est) stages of AD-related pathology. These changes in monoaminergic neurochemistry could provide for relevant targets for intervention in clinical AD and/or could support a polypharmacy strategy, which might include the targeting of Aβ, in vulnerable populations. Future studies must also include female mice as well as male mice in animal model studies on the relationship between depression and AD.
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Affiliation(s)
- Jennifer N K Nyarko
- 1 Cell Signalling Laboratory, Department of Psychiatry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Maa O Quartey
- 1 Cell Signalling Laboratory, Department of Psychiatry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Glen B Baker
- 2 Department of Psychiatry, Neuroscience and Mental Health Institute, Neurochemical Research Unit, University of Alberta, Edmonton, Alberta, Canada
| | - Darrell D Mousseau
- 1 Cell Signalling Laboratory, Department of Psychiatry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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17
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Lalut J, Santoni G, Karila D, Lecoutey C, Davis A, Nachon F, Silman I, Sussman J, Weik M, Maurice T, Dallemagne P, Rochais C. Novel multitarget-directed ligands targeting acetylcholinesterase and σ 1 receptors as lead compounds for treatment of Alzheimer's disease: Synthesis, evaluation, and structural characterization of their complexes with acetylcholinesterase. Eur J Med Chem 2018; 162:234-248. [PMID: 30447434 DOI: 10.1016/j.ejmech.2018.10.064] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 10/24/2018] [Accepted: 10/29/2018] [Indexed: 12/19/2022]
Abstract
Pleiotropic intervention may be a requirement for effective limitation of the progression of multifactorial diseases such as Alzheimer's Disease. One approach to such intervention is to design a single chemical entity capable of acting on two or more targets of interest, which are accordingly known as Multi-Target Directed Ligands (MTDLs). We recently described donecopride, the first MTDL able to simultaneously inhibit acetylcholinesterase and act as an agonist of the 5-HT4 receptor, which displays promising activities in vivo. Pharmacomodulation of donecopride allowed us to develop a novel series of indole derivatives possessing interesting in vitro activities toward AChE and the σ1 receptor. The crystal structures of complexes of the most promising compounds with Torpedo californica AChE were solved in order to further understand their mode of inhibition.
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Affiliation(s)
- Julien Lalut
- Centre d'Etudes et de Recherche sur le Médicament de Normandie, Normandie Univ, UNICAEN, CERMN, 14000, Caen, France
| | - Gianluca Santoni
- Univ Grenoble Alpes, IBS, F-38027, Grenoble, France; CNRS, IBS, F-38027, Grenoble, France; CEA, IBS, F-38027, Grenoble, France
| | - Delphine Karila
- Centre d'Etudes et de Recherche sur le Médicament de Normandie, Normandie Univ, UNICAEN, CERMN, 14000, Caen, France
| | - Cédric Lecoutey
- Centre d'Etudes et de Recherche sur le Médicament de Normandie, Normandie Univ, UNICAEN, CERMN, 14000, Caen, France
| | - Audrey Davis
- Centre d'Etudes et de Recherche sur le Médicament de Normandie, Normandie Univ, UNICAEN, CERMN, 14000, Caen, France
| | - Florian Nachon
- Département de Toxicologie et Risques Chimiques, Institut de Recherche Biomédicale des Armées, 91220, Brétigny-sur-Orge, France
| | - Israel Silman
- Department of Neurobiology, Weizmann Institute of Science, 76100, Rehovot, Israel
| | - Joel Sussman
- Department of Structural Biology, Weizmann Institute of Science, 76100, Rehovot, Israel
| | - Martin Weik
- Univ Grenoble Alpes, IBS, F-38027, Grenoble, France; CNRS, IBS, F-38027, Grenoble, France; CEA, IBS, F-38027, Grenoble, France
| | - Tangui Maurice
- Molecular Mechanisms in Neurodegenerative Diseases, MMDN Laboratory, University of Montpellier, Ecole Pratique des Hautes Etudes, Institut National de la Recherche et de la Santé Médicale, UMR-S1198, 34095, Montpellier, France
| | - Patrick Dallemagne
- Centre d'Etudes et de Recherche sur le Médicament de Normandie, Normandie Univ, UNICAEN, CERMN, 14000, Caen, France.
| | - Christophe Rochais
- Centre d'Etudes et de Recherche sur le Médicament de Normandie, Normandie Univ, UNICAEN, CERMN, 14000, Caen, France.
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18
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Nirogi R, Mohammed AR, Shinde AK, Gagginapally SR, Kancharla DM, Middekadi VR, Bogaraju N, Ravella SR, Singh P, Birangal SR, Subramanian R, Palacharla RC, Benade V, Muddana N, Jayarajan P. Synthesis, Structure-Activity Relationships, and Preclinical Evaluation of Heteroaromatic Amides and 1,3,4-Oxadiazole Derivatives as 5-HT 4 Receptor Partial Agonists. J Med Chem 2018; 61:4993-5008. [PMID: 29763304 DOI: 10.1021/acs.jmedchem.8b00457] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder that has a higher prevalence and incidence in people older than 60 years. The need for improved AD therapies is unmet as the current therapies are symptomatic with modest efficacy. Partial agonists of the 5-HT4 receptor (5-HT4R) offer both symptomatic and disease-modifying treatments as they shift amyloid-precursor-protein (APP) processing from the amyloidogenic pathway to the nonamyloidogenic pathway by activating the α-secretase enzyme. In addition, they also offer symptomatic treatment by increasing levels of the neurotransmitter acetylcholine in the brain. Because of this fascinating dual mechanism of action, several chemical scaffolds having 5-HT4R pharmacophores were designed and evaluated. Most of the synthesized compounds showed potent in vitro affinities and in vivo efficacies. Upon analysis of focused structure-activity relationships, compound 4o was identified as a potent 5-HT4R partial agonist with favorable ADME properties and good in vivo efficacy. GR-125487, a selective 5-HT4R antagonist, attenuated the activity of compound 4o in the novel-object-recognition-test cognition model.
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Affiliation(s)
- Ramakrishna Nirogi
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Abdul Rasheed Mohammed
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Anil K Shinde
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Shankar Reddy Gagginapally
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Durga Malleshwari Kancharla
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Vanaja Reddy Middekadi
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Narsimha Bogaraju
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Srinivasa Rao Ravella
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Pooja Singh
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Sumit Raosaheb Birangal
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Ramkumar Subramanian
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Raghava Choudary Palacharla
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Vijay Benade
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Nageswararao Muddana
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
| | - Pradeep Jayarajan
- Discovery Research , Suven Life Sciences Limited , Serene Chambers, Road-5, Avenue-7, Banjara Hills , Hyderabad 500 034 , India
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19
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Nirogi R, Gagginapally SR, Shinde AK, Mohammed AR. Synthesis of GR 125487, a selective 5-HT 4 receptor antagonist. SYNTHETIC COMMUN 2016. [DOI: 10.1080/00397911.2016.1178297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
| | | | - Anil K. Shinde
- Discovery Research, Suven Life Sciences Ltd., Hyderabad, India
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20
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Hagena H, Manahan-Vaughan D. The serotonergic 5-HT4 receptor: A unique modulator of hippocampal synaptic information processing and cognition. Neurobiol Learn Mem 2016; 138:145-153. [PMID: 27317942 DOI: 10.1016/j.nlm.2016.06.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/06/2016] [Accepted: 06/14/2016] [Indexed: 01/10/2023]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) contributes in multifarious ways to the regulation of brain function, spanning key aspects such as the sleep-wake cycle, appetite, mood and mental health. The 5-HT receptors comprise seven receptor families (5-HT1-7) that are further subdivided into 14 receptor subtypes. The role of the 5-HT receptor in the modulation of neuronal excitability has been well documented. Recently, however, it has become apparent that the 5-HT4 receptor may contribute significantly to cognition and regulates less ostensible aspects of brain function: it engages in metaplastic regulation of synaptic responsiveness in key brain structures such as the hippocampus, thereby specifically promoting persistent forms of synaptic plasticity, and influences the direction of change in synaptic strength in selected hippocampal subfields. This highly specific neuromodulatory control by the 5-HT4 receptor may in turn explain the reported role for this receptor in hippocampus-dependent cognition. In this review article, we describe the role of the 5-HT4 receptor in hippocampal function, and describe how this receptor plays a unique and highly specialised role in synaptic information storage and cognition.
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Affiliation(s)
- Hardy Hagena
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Germany
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21
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Bellini M, Gambaccini D, Bassotti G. Prucalopride: For functional constipation only? Tech Coloproctol 2016; 20:433-6. [PMID: 27174045 DOI: 10.1007/s10151-016-1477-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 04/29/2016] [Indexed: 01/25/2023]
Abstract
Prucalopride is a new prokinetic agent, recently available in Europe for the treatment of functional constipation in adults in whom treatment with laxatives failed to provide adequate relief. However, due to its intrinsic properties (highly selective agonist activity and high affinity for 5-HT4 receptors, neuroprotection), this drug has shown the potential to be used in other pathologic conditions, in and outside of the gastrointestinal tract. We performed a systematic review of the evidence supporting these possible alternative uses of prucalopride. Further studies in this area are, however, mandatory.
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Affiliation(s)
- M Bellini
- Gastrointestinal Unit, Department of Gastroenterology, University of Pisa, Pisa, Italy
| | - D Gambaccini
- Gastrointestinal Unit, Department of Gastroenterology, University of Pisa, Pisa, Italy
| | - G Bassotti
- Gastroenterology and Hepatology Section, Department of Medicine, University of Perugia Medical School, Piazza Lucio Severi, 1, 06132, San Sisto (Perugia), Italy.
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22
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Nirogi R, Mohammed AR, Shinde AK, Bogaraju N, Gagginapalli SR, Ravella SR, Kota L, Bhyrapuneni G, Muddana NR, Benade V, Palacharla RC, Jayarajan P, Subramanian R, Goyal VK. Synthesis and SAR of Imidazo[1,5-a]pyridine derivatives as 5-HT4 receptor partial agonists for the treatment of cognitive disorders associated with Alzheimer's disease. Eur J Med Chem 2015; 103:289-301. [PMID: 26363507 DOI: 10.1016/j.ejmech.2015.08.051] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/25/2015] [Accepted: 08/26/2015] [Indexed: 11/16/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease which has a higher prevalence and incidence in older people. The need for improved AD therapies is unmet. The 5-hydroxytryptamine4 receptor (5-HT4R) partial agonists may be of benefit for both the symptomatic and disease-modifying treatment of cognitive disorders associated with AD. Herein, we report the design, synthesis and SAR of imidazo[1,5-a] pyridine derivatives as 5-HT4R partial agonists. The focused SAR, optimization of ADME properties resulted the discovery of compound 5a as potent, selective, brain penetrant 5-HT4 partial agonist as a lead compound with good ADME properties and efficacy in both symptomatic and disease modifying animal models of cognition.
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Affiliation(s)
- Ramakrishna Nirogi
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India.
| | - Abdul Rasheed Mohammed
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Anil K Shinde
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Narsimha Bogaraju
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Shankar Reddy Gagginapalli
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Srinivasa Rao Ravella
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Laxman Kota
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Gopinadh Bhyrapuneni
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Nageswara Rao Muddana
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Vijay Benade
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Raghava Chowdary Palacharla
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Pradeep Jayarajan
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Ramkumar Subramanian
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
| | - Vinod Kumar Goyal
- Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad, 500 034, India
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23
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Mendez-David I, David DJ, Darcet F, Wu MV, Kerdine-Römer S, Gardier AM, Hen R. Rapid anxiolytic effects of a 5-HT₄ receptor agonist are mediated by a neurogenesis-independent mechanism. Neuropsychopharmacology 2014; 39:1366-78. [PMID: 24287720 PMCID: PMC3988540 DOI: 10.1038/npp.2013.332] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 11/16/2013] [Accepted: 11/20/2013] [Indexed: 12/15/2022]
Abstract
Selective serotonin reuptake inhibitors (SSRIs) display a delayed onset of action of several weeks. Past work in naive rats showed that 5-HT₄ receptor agonists had rapid effects on depression-related behaviors and on hippocampal neurogenesis. We decided to investigate whether 5-HT₄ receptor stimulation was necessary for the effects of SSRIs in a mouse model of anxiety/depression, and whether hippocampal neurogenesis contributed to these effects. Using the mouse corticosterone model of anxiety/depression, we assessed whether chronic treatment with a 5-HT₄ receptor agonist (RS67333, 1.5 mg/kg/day) had effects on anxiety- and depression-related behaviors, as well as on hippocampal neurogenesis in comparison with chronic fluoxetine treatment (18 mg/kg/day). Then, using our anxiety/depression model combined with ablation of hippocampal neurogenesis, we investigated whether neurogenesis was necessary for the behavioral effects of subchronic (7 days) or chronic (28 days) RS67333 treatment. We also assessed whether a 5-HT₄ receptor antagonist (GR125487, 1 mg/kg/day) could prevent the behavioral and neurogenic effects of fluoxetine. Chronic treatment with RS67333, similar to fluoxetine, induced anxiolytic/antidepressant-like activity and stimulated adult hippocampal neurogenesis, specifically facilitating maturation of newborn neurons. However, unlike fluoxetine, anxiolytic effects of RS67333 were already present after 7 days and did not require hippocampal neurogenesis. Chronic treatment with GR125487 prevented both anxiolytic/antidepressant-like and neurogenic effects of fluoxetine, indicating that 5-HT₄ receptor activation is necessary for these effects of SSRIs. 5-HT₄ receptor stimulation could represent an innovative and rapid onset therapeutic approach to treat depression with comorbid anxiety.
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Affiliation(s)
| | - Denis J David
- Univ Paris Sud, EA3544, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Flavie Darcet
- Univ Paris Sud, EA3544, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Melody V Wu
- Departments of Neuroscience and Psychiatry, Columbia University, New York, NY, USA,Department of Integrative Neuroscience, New York State Psychiatric Institute, New York, NY, USA
| | | | - Alain M Gardier
- Univ Paris Sud, EA3544, Faculté de Pharmacie, Châtenay-Malabry, France
| | - René Hen
- Departments of Neuroscience and Psychiatry, Columbia University, New York, NY, USA,Department of Integrative Neuroscience, New York State Psychiatric Institute, New York, NY, USA,Departments of Neuroscience and Psychiatry, Columbia University, New York, NY 10032, USA, Tel: +1 212 543 5328, Fax: +1 212 543 5074, E-mail:
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24
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Regulation of amyloid precursor protein processing by serotonin signaling. PLoS One 2014; 9:e87014. [PMID: 24466315 PMCID: PMC3897773 DOI: 10.1371/journal.pone.0087014] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 12/16/2013] [Indexed: 11/25/2022] Open
Abstract
Proteolytic processing of the amyloid precursor protein (APP) by the β- and γ-secretases releases the amyloid-β peptide (Aβ), which deposits in senile plaques and contributes to the etiology of Alzheimer's disease (AD). The α-secretase cleaves APP in the Aβ peptide sequence to generate soluble APPα (sAPPα). Upregulation of α-secretase activity through the 5-hydroxytryptamine 4 (5-HT4) receptor has been shown to reduce Aβ production, amyloid plaque load and to improve cognitive impairment in transgenic mouse models of AD. Consequently, activation of 5-HT4 receptors following agonist stimulation is considered to be a therapeutic strategy for AD treatment; however, the signaling cascade involved in 5-HT4 receptor-stimulated proteolysis of APP remains to be determined. Here we used chemical and siRNA inhibition to identify the proteins which mediate 5-HT4d receptor-stimulated α-secretase activity in the SH-SY5Y human neuronal cell line. We show that G protein and Src dependent activation of phospholipase C are required for α-secretase activity, while, unexpectedly, adenylyl cyclase and cAMP are not involved. Further elucidation of the signaling pathway indicates that inositol triphosphate phosphorylation and casein kinase 2 activation is also a prerequisite for α-secretase activity. Our findings provide a novel route to explore the treatment of AD through 5-HT4 receptor-induced α-secretase activation.
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25
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Giannoni P, Gaven F, de Bundel D, Baranger K, Marchetti-Gauthier E, Roman FS, Valjent E, Marin P, Bockaert J, Rivera S, Claeysen S. Early administration of RS 67333, a specific 5-HT4 receptor agonist, prevents amyloidogenesis and behavioral deficits in the 5XFAD mouse model of Alzheimer's disease. Front Aging Neurosci 2013; 5:96. [PMID: 24399967 PMCID: PMC3871961 DOI: 10.3389/fnagi.2013.00096] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 12/06/2013] [Indexed: 01/14/2023] Open
Abstract
Amyloid β (Aβ) accumulation is considered the main culprit in the pathogenesis of Alzheimer’s disease (AD). Recent studies suggest that decreasing Aβ production at very early stages of AD could be a promising strategy to slow down disease progression. Serotonin 5-HT4 receptor activation stimulates α-cleavage of the amyloid precursor protein (APP), leading to the release of the soluble and neurotrophic sAPPα fragment and thus precluding Aβ formation. Using the 5XFAD mouse model of AD that shows accelerated Aβ deposition, we investigated the effect of chronic treatments (treatment onset at different ages and different durations) with the 5-HT4 receptor agonist RS 67333 during the asymptomatic phase of the disease. Chronic administration of RS 67333 decreased concomitantly the number of amyloid plaques and the level of Aβ species. Reduction of Aβ levels was accompanied by a striking decrease in hippocampal astrogliosis and microgliosis. RS 67333 also transiently increased sAPPα concentration in the cerebrospinal fluid and brain. Moreover, a specific 5-HT4 receptor antagonist (RS 39604) prevented the RS 67333-mediated reduction of the amyloid pathology. Finally, the novel object recognition test deficits of 5XFAD mice were reversed by chronic treatment with RS 67333. Collectively, these results strongly highlight this 5-HT4 receptor agonist as a promising disease modifying-agent for AD.
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Affiliation(s)
- Patrizia Giannoni
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle Montpellier, France ; Inserm, U661 Montpellier, France ; Universités de Montpellier 1 and 2, UMR-5203 Montpellier, France
| | - Florence Gaven
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle Montpellier, France ; Inserm, U661 Montpellier, France ; Universités de Montpellier 1 and 2, UMR-5203 Montpellier, France
| | - Dimitri de Bundel
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle Montpellier, France ; Inserm, U661 Montpellier, France ; Universités de Montpellier 1 and 2, UMR-5203 Montpellier, France
| | - Kevin Baranger
- Aix-Marseille Univ, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France ; CNRS, NICN, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France ; Service de Neurologie et de Neuropsychologie, CHU La Timone, AP-HM Marseille, France
| | - Evelyne Marchetti-Gauthier
- Aix-Marseille Univ, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France ; CNRS, NICN, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France
| | - François S Roman
- Aix-Marseille Univ, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France ; CNRS, NICN, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France
| | - Emmanuel Valjent
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle Montpellier, France ; Inserm, U661 Montpellier, France ; Universités de Montpellier 1 and 2, UMR-5203 Montpellier, France
| | - Philippe Marin
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle Montpellier, France ; Inserm, U661 Montpellier, France ; Universités de Montpellier 1 and 2, UMR-5203 Montpellier, France
| | - Joël Bockaert
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle Montpellier, France ; Inserm, U661 Montpellier, France ; Universités de Montpellier 1 and 2, UMR-5203 Montpellier, France
| | - Santiago Rivera
- Aix-Marseille Univ, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France ; CNRS, NICN, Neurobiologie des Interactions Cellulaires et Neurophysiopathologie, UMR 7259 Marseille, France
| | - Sylvie Claeysen
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle Montpellier, France ; Inserm, U661 Montpellier, France ; Universités de Montpellier 1 and 2, UMR-5203 Montpellier, France
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Cheng X, Wu J, Geng M, Xiong J. Role of synaptic activity in the regulation of amyloid beta levels in Alzheimer's disease. Neurobiol Aging 2013; 35:1217-32. [PMID: 24368087 DOI: 10.1016/j.neurobiolaging.2013.11.021] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Revised: 11/03/2013] [Accepted: 11/24/2013] [Indexed: 01/27/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. Accumulation of amyloid-beta (Aβ) peptides is regarded as the critical component associated with AD pathogenesis, which is derived from the amyloid precursor protein (APP) cleavage. Recent studies suggest that synaptic activity is one of the most important factors that regulate Aβ levels. It has been found that synaptic activity facilitates APP internalization and influences APP cleavage. Glutamatergic, cholinergic, serotonergic, leptin, adrenergic, orexin, and gamma-amino butyric acid receptors, as well as the activity-regulated cytoskeleton-associated protein (Arc) are all involved in these processes. The present review summarizes the evidence for synaptic activity-modulated Aβ levels and the mechanisms underlying this regulation. Interestingly, the immediate early gene product Arc may also be the downstream signaling molecule of several receptors in the synaptic activity-modulated Aβ levels. Elucidating how Aβ levels are regulated by synaptic activity may provide new insights in both the understanding of the pathogenesis of AD and in the development of therapies to slow down the progression of AD.
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Affiliation(s)
- Xiaofang Cheng
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Jian Wu
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Miao Geng
- Institute of Geriatrics, General Hospital of Chinese PLA, Beijing, China
| | - Jiaxiang Xiong
- Department of Physiology, Third Military Medical University, Chongqing, China.
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Tesseur I, Pimenova AA, Lo AC, Ciesielska M, Lichtenthaler SF, De Maeyer JH, Schuurkes JAJ, D'Hooge R, De Strooper B. Chronic 5-HT4 receptor activation decreases Aβ production and deposition in hAPP/PS1 mice. Neurobiol Aging 2013; 34:1779-89. [PMID: 23474291 DOI: 10.1016/j.neurobiolaging.2013.01.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 01/08/2013] [Accepted: 01/26/2013] [Indexed: 01/09/2023]
Abstract
Lowering the production and accumulation of Aβ has been explored as treatment for Alzheimer's disease (AD), because Aβ is postulated to play an important role in the pathogenesis of AD. 5-HT4 receptors are an interesting drug target in this regard, as their activation might stimulate α-secretase processing, which increases sAPPα and reduces Aβ, at least according to the central dogma in APP processing. Here we describe a novel high-affinity 5-HT4 receptor agonist SSP-002392 that, in cultured human neuroblastoma cells, potently increases the levels of cAMP and sAPPα at 100-fold lower concentrations than the effective concentrations of prucalopride, a known selective 5-HT4 receptor agonist. Chronic administration of this compound in a hAPP/PS1 mouse model of Alzheimer's disease decreased soluble and insoluble Aβ in hippocampus, but the potential mechanisms underlying these observations seem to be complex. We found no evidence for direct α-secretase stimulation in the brain in vivo, but observed decreased APP and BACE-1 expression and elevated astroglia and microglia responses. Taken together these results provide support for a potential disease-modifying aspect when stimulating central 5-HT4 receptors; however, the complexity of the phenomena warrants further research.
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Affiliation(s)
- Ina Tesseur
- Center for Human Genetics, Leuven Research Institute for Neuroscience and Disease (LIND), University of Leuven, Leuven, Belgium
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Nirogi R, Kandikere V, Bhyrapuneni G, Saralaya R, Ajjala DR, Aleti RR, Rasheed MA. In-vivo rat striatal 5-HT4 receptor occupancy using non-radiolabelled SB207145. J Pharm Pharmacol 2013; 65:704-12. [DOI: 10.1111/jphp.12030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 12/19/2012] [Indexed: 12/18/2022]
Abstract
Abstract
Objectives
The objective of the current investigation was to develop a simple, rapid method for determining in-vivo 5-hydroxytryptamine type 4 receptor (5-HT4R) occupancy in rat brain using non-radiolabelled SB207145 as a tracer for accelerating the drug discovery process.
Methods
In-vivo tracer optimization studies for tracer dose, survival intervals and brain distribution profile were carried out in rats. The tracer was pharmacologically validated using potent well-characterized 5-HT4R ligands. The brain regional concentrations of tracer (SB207145); plasma and brain concentrations of 5-HT4R ligands were quantified using high-performance liquid chromatography coupled with a tandem mass spectrometric detector (LC-MS/MS).
Key findings
SB207145 showed a higher specific binding in striatum (1.96 ng/g) and lower binding in cerebellum (0.66 ng/g), which is consistent with findings of other published 5-HT4R expression studies. Pretreatment with potent 5-HT4 ligands dose-dependently reduced striatal SB207145 concentration and the effective dose to achieve 50% receptor occupancy (ED50) values were 4.8, 2.0, 7.4, 9.9, 3.8 and 0.02 mg/kg for GR113808, piboserod, prucalopride, RS67333, TD8954 and PF04995274, respectively.
Conclusions
Results from the mass spectrometry approach to determine 5-HT4R occupancy in rat brain are comparable with those reported using radiolabelled scintillation spectroscopy methods. In conclusion, the LC-MS/MS characterization permits use of tracer at a preclinical stage in high-throughput fashion as well as characterization of target expression.
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Affiliation(s)
- Ramakrishna Nirogi
- Pharmacokinetics and Drug Metabolism, Suven Life Sciences Ltd, Hyderabad, India
- Department of Medicinal Chemistry, Discovery Research, Suven Life Sciences Ltd, Hyderabad, India
| | | | | | - Ramanatha Saralaya
- Pharmacokinetics and Drug Metabolism, Suven Life Sciences Ltd, Hyderabad, India
| | | | | | - Mohammed Abdul Rasheed
- Department of Medicinal Chemistry, Discovery Research, Suven Life Sciences Ltd, Hyderabad, India
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Lu Q, Chen WY, Zhu ZY, Chen J, Xu YC, Kaewpet M, Rukachaisirikul V, Chen LL, Shen X. L655,240, acting as a competitive BACE1 inhibitor, efficiently decreases β-amyloid peptide production in HEK293-APPswe cells. Acta Pharmacol Sin 2012; 33:1459-68. [PMID: 22842730 DOI: 10.1038/aps.2012.74] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
AIM To identify a small molecule L655,240 as a novel β-secretase (BACE1) inhibitor and to investigate its effects on β-amyloid (Aβ) generation in vitro. METHODS Fluorescence resonance energy transfer (FRET) was used to characterize the inhibitory effect of L655,240 on BACE1. Surface plasmon resonance (SPR) technology-based assay was performed to study the binding affinity of L655,240 for BACE1. The selectivity of L655,240 toward BACE1 over other aspartic proteases was determined with enzymatic assay. The effects of L655,240 on Aβ40, Aβ42, and sAPPβ production were studied in HEK293 cells stably expressing APP695 Swedish mutant(K595N/M596L) (HEK293-APPswe cells). The activities of BACE1, γ-secretase and α-secretase were assayed, and both the mRNA and protein levels of APP and BACE1 were evaluated using real-time PCR (RT-PCR) and Western blot analysis. RESULTS L655,240 was determined to be a competitive, selective BACE1 inhibitor (IC(50)=4.47±1.37 μmol/L), which bound to BACE1 directly (K(D)=17.9±0.72 μmol/L). L655,240 effectively reduced Aβ40, Aβ42, and sAPPβ production by inhibiting BACE1 without affecting the activities of γ-secretase and α-secretase in HEK293-APPswe cells. L655,240 has no effect on APP and BACE1 mRNA or protein levels in HEK293-APPswe cells. CONCLUSION The small molecule L655,240 is a novel BACE1 inhibitor that can effectively decreases Aβ production in vitro, thereby highlighting its therapeutic potential for the treatment of Alzheimer's disease.
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Rodríguez JJ, Noristani HN, Verkhratsky A. The serotonergic system in ageing and Alzheimer's disease. Prog Neurobiol 2012; 99:15-41. [DOI: 10.1016/j.pneurobio.2012.06.010] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Revised: 05/24/2012] [Accepted: 06/22/2012] [Indexed: 01/11/2023]
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Claeysen S, Cochet M, Donneger R, Dumuis A, Bockaert J, Giannoni P. Alzheimer culprits: cellular crossroads and interplay. Cell Signal 2012; 24:1831-40. [PMID: 22627093 DOI: 10.1016/j.cellsig.2012.05.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 05/09/2012] [Indexed: 12/22/2022]
Abstract
Alzheimer's disease (AD) is the primary cause of dementia in the elderly and one of the major health problems worldwide. Since its first description by Alois Alzheimer in 1907, noticeable but insufficient scientific comprehension of this complex pathology has been achieved. All the research that has been pursued takes origin from the identification of the pathological hallmarks in the forms of amyloid-β (Aβ) deposits (plaques), and aggregated hyperphosphorylated tau protein filaments (named neurofibrillary tangles). Since this discovery, many hypotheses have been proposed to explain the origin of the pathology. The "amyloid cascade hypothesis" is the most accredited theory. The mechanism suggested to be one of the initial causes of AD is an imbalance between the production and the clearance of Aβ peptides. Therefore, Amyloid Precursor Protein (APP) synthesis, trafficking and metabolism producing either the toxic Aβ peptide via the amyloidogenic pathway or the sAPPα fragment via the non amyloidogenic pathway have become appealing subjects of study. Being able to reduce the formation of the toxic Aβ peptides is obviously an immediate approach in the trial to prevent AD. The following review summarizes the most relevant discoveries in the field of the last decades.
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Affiliation(s)
- Sylvie Claeysen
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, F-34000 Montpellier, France.
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Abstract
Alpha-secretase-mediated cleavage of the amyloid precursor protein (APP) releases the neuroprotective APP fragment sαAPP and prevents amyloid β peptide (Aβ) generation. Moreover, α-secretase-like cleavage of the Aβ transporter 'receptor for advanced glycation end products' counteracts the import of blood Aβ into the brain. Assuming that Aβ is responsible for the development of Alzheimer's disease (AD), activation of α-secretase should be preventive. α-Secretase-mediated APP cleavage can be activated via several G protein-coupled receptors and receptor tyrosine kinases. Protein kinase C, mitogen-activated protein kinases, phosphatidylinositol 3-kinase, cAMP and calcium are activators of receptor-induced α-secretase cleavage. Selective targeting of receptor subtypes expressed in brain regions affected by AD appears reasonable. Therefore, the PACAP receptor PAC1 and possibly the serotonin 5-HT(6) receptor subtype are promising targets. Activation of APP α-secretase cleavage also occurs upon blockade of cholesterol synthesis by statins or zaragozic acid A. Under physiological statin concentrations, the brain cholesterol content is not influenced. Statins likely inhibit Aβ production in the blood by α-secretase activation which is possibly sufficient to inhibit AD development. A disintegrin and metalloproteinase 10 (ADAM10) acts as α-secretase on APP. By targeting the nuclear retinoic acid receptor β, the expression of ADAM10 and non-amyloidogenic APP processing can be enhanced. Excessive activation of ADAM10 should be avoided because ADAM10 and also ADAM17 are not APP-specific. Both ADAM proteins cleave various substrates, and therefore have been associated with tumorigenesis and tumor progression.
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Affiliation(s)
- Rolf Postina
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz, Johann-Joachim-Becherweg 30, Mainz, Germany
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Madsen K, Marner L, Haahr M, Gillings N, Knudsen GM. Mass dose effects and in vivo affinity in brain PET receptor studies — a study of cerebral 5-HT4 receptor binding with [11C]SB207145. Nucl Med Biol 2011; 38:1085-91. [DOI: 10.1016/j.nucmedbio.2011.04.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 02/28/2011] [Accepted: 04/28/2011] [Indexed: 01/24/2023]
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Abstract
Mounting evidence accumulated over the past few years indicates that the neurotransmitter serotonin plays a significant role in cognition. As a drug target, serotonin receptors have received notable attention due in particular to the role of several serotonin-receptor subclasses in cognition and memory. The intimate anatomical and neurochemical association of the serotonergic system with brain areas that regulate memory and learning has directed current drug discovery programmes to focus on this system as a major therapeutic drug target. Thus far, none of these programmes has yielded unambiguous data that suggest that any of the new drug entities possesses disease-modifying properties, and significantly more research in this promising area of investigation is required. Compounds are currently being investigated for activity against serotonin 5-HT(1), 5-HT(4) and 5-HT(6) receptors. This review concludes that most work done in the development of selective serotonin receptor ligands is in the pre-clinical or early clinical phase. Also, while many of these compounds will likely find application as adjuvant therapy in the symptomatic treatment of Alzheimer's disease, there are currently only a few drug entities with activity against serotonin receptors that may offer the potential to alter the progression of the disease.
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Affiliation(s)
- Werner J Geldenhuys
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, USA
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5-HT4 receptor agonist mediated enhancement of cognitive function in vivo and amyloid precursor protein processing in vitro: A pharmacodynamic and pharmacokinetic assessment. Neuropharmacology 2011; 61:69-79. [DOI: 10.1016/j.neuropharm.2011.02.026] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 02/16/2011] [Accepted: 02/25/2011] [Indexed: 01/14/2023]
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Terry AV, Callahan PM, Hall B, Webster SJ. Alzheimer's disease and age-related memory decline (preclinical). Pharmacol Biochem Behav 2011; 99:190-210. [PMID: 21315756 DOI: 10.1016/j.pbb.2011.02.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 01/21/2011] [Accepted: 02/01/2011] [Indexed: 01/05/2023]
Abstract
An unfortunate result of the rapid rise in geriatric populations worldwide is the increasing prevalence of age-related cognitive disorders such as Alzheimer's disease (AD). AD is a devastating neurodegenerative illness that is characterized by a profound impairment of cognitive function, marked physical disability, and an enormous economic burden on the afflicted individual, caregivers, and society in general. The rise in elderly populations is also resulting in an increase in individuals with related (potentially treatable) conditions such as "Mild Cognitive Impairment" (MCI) which is characterized by a less severe (but abnormal) level of cognitive impairment and a high-risk for developing dementia. Even in the absence of a diagnosable disorder of cognition (e.g., AD and MCI), the perception of increased forgetfulness and declining mental function is a clear source of apprehension in the elderly. This is a valid concern given that even a modest impairment of cognitive function is likely to be associated with significant disability in a rapidly evolving, technology-based society. Unfortunately, the currently available therapies designed to improve cognition (i.e., for AD and other forms of dementia) are limited by modest efficacy and adverse side effects, and their effects on cognitive function are not sustained over time. Accordingly, it is incumbent on the scientific community to develop safer and more effective therapies that improve and/or sustain cognitive function in the elderly allowing them to remain mentally active and productive for as long as possible. As diagnostic criteria for memory disorders evolve, the demand for pro-cognitive therapeutic agents is likely to surpass AD and dementia to include MCI and potentially even less severe forms of memory decline. The purpose of this review is to provide an overview of the contemporary therapeutic targets and preclinical pharmacologic approaches (with representative drug examples) designed to enhance memory function.
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Affiliation(s)
- Alvin V Terry
- Department of Pharmacology and Toxicology and Small Animal Behavior Core, Medical College of Georgia, Augusta, GA 30912, USA.
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Bockaert J, Claeysen S, Compan V, Dumuis A. 5-HT(4) receptors, a place in the sun: act two. Curr Opin Pharmacol 2011; 11:87-93. [PMID: 21342787 DOI: 10.1016/j.coph.2011.01.012] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 01/28/2011] [Accepted: 01/31/2011] [Indexed: 10/18/2022]
Abstract
5-HT(4) receptors control brain physiological functions such as learning and memory, feeding and mood behaviour as well as gastro-intestinal transit. 5-HT(4) receptors are one of the 5-HT receptors for which the available drugs and signalling knowledge are the most advanced. Several therapeutic 5-HT(4) receptor drugs have been commercialized. Therefore, the hope that 5-HT(4) receptors could also be the target for brain diseases is reasonable. Several major devastating illnesses could benefit from 5-HT(4) receptors-directed therapy such as Alzheimer's disease, feeding-associated diseases such as anorexia and major depressive disorders.
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Affiliation(s)
- Joël Bockaert
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS UMR5203, Montpellier F-34094, France.
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Thathiah A, De Strooper B. The role of G protein-coupled receptors in the pathology of Alzheimer's disease. Nat Rev Neurosci 2011; 12:73-87. [DOI: 10.1038/nrn2977] [Citation(s) in RCA: 212] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Martorana A, Esposito Z, Koch G. Beyond the cholinergic hypothesis: do current drugs work in Alzheimer's disease? CNS Neurosci Ther 2010; 16:235-45. [PMID: 20560995 DOI: 10.1111/j.1755-5949.2010.00175.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease characterized by memory and cognitive loss, and represents the leading cause of dementia in elderly people. Besides the complex biochemical processes involved in the neuronal degeneration (formation of senile plaques containing Abeta peptides, and development of neurofibrillary tangles), other molecular and neurochemical alterations, like cholinergic deficit due to basal forebrain degeneration, also occur. Because acetylcholine has been demonstrated to be involved in cognitive processes, the idea to increase acetylcholine levels to restore cognitive deficits has gained interest (the so-called cholinergic hypothesis). This has led to the development of drugs able to prevent acetylcholine hydrolysis (acetylcholinesterase inhibitors). However, the analysis of clinical efficacy of these drugs in alleviating symptoms of dementia showed unsatisfactory results. Despite such critical opinions on the efficacy of these drugs, it should be said that acetylcholinesterase inhibitors, and for some aspects memantine also, improve memory and other cognitive functions throughout most of the duration of the disease. The pharmacological activity of these drugs suggests an effect beyond the mere increase of acetylcholine levels. These considerations are in agreement with the idea that cognitive decline is the result of a complex and not fully elucidated interplay among different neurotransmitters. The role of each of the neurotransmitters implicated has to be related to a cognitive process and as a consequence to its decline. The current review aims to highlight the positive role of cholinergic drugs in alleviating cognitive deficits during wake as well as sleep. Moreover, we suggest that future therapeutic approaches have to be developed to restore the complex interplay between acetylcholine and other neurotransmitters systems, such as dopamine, serotonin, noradrenaline, or glutamate, that are likely involved in the progressive deterioration of several cognitive functions such as attention, memory, and learning.
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Affiliation(s)
- Alessandro Martorana
- Clinica Neurologica, Dipartimento di Neuroscienze, Università di Roma "Tor Vergata", Rome, Italy.
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Thathiah A, De Strooper B. G protein-coupled receptors, cholinergic dysfunction, and Abeta toxicity in Alzheimer's disease. Sci Signal 2009; 2:re8. [PMID: 19843960 DOI: 10.1126/scisignal.293re8] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The beta-amyloid (Abeta) peptide is associated with the pathogenesis of Alzheimer's disease (AD). Evidence gathered over the last two decades suggests that the gradual accumulation of soluble and insoluble Abeta peptide species triggers a cascade of events that leads to the clinical manifestation of AD. Abeta accumulation has also been associated with the cholinergic dysfunction observed in AD, which is characterized by diminished acetylcholine release and impaired coupling of the muscarinic acetylcholine receptors (mAChRs) to heterotrimeric GTP-binding proteins (G proteins). Although the mechanism of Abeta-mediated toxicity is not clearly understood, evidence shows that Abeta accumulation has an effect on the oligomerization of the angiotensin II (AngII) AT(2) (angiotensin type 2) receptor and sequestration of the Galpha(q/11) family of G proteins. Sequestration of Galpha(q/11) results in dysfunctional coupling and signaling between M(1) mAChR and Galpha(q/11) and accompanies neurodegeneration, tau phosphorylation, and neuronal loss in an AD transgenic mouse model. Collectively, these results provide a putative link among Abeta toxicity, AT(2) receptor oligomerization, and disruption of the signaling pathway through M(1) mAChR and Galpha(q/11) and potentially contribute to our understanding of the cholinergic deficit observed in AD.
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Marner L, Gillings N, Comley RA, Baaré WFC, Rabiner EA, Wilson AA, Houle S, Hasselbalch SG, Svarer C, Gunn RN, Laruelle M, Knudsen GM. Kinetic modeling of 11C-SB207145 binding to 5-HT4 receptors in the human brain in vivo. J Nucl Med 2009; 50:900-8. [PMID: 19470850 DOI: 10.2967/jnumed.108.058552] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The serotonin 4 receptor (5-HT(4) receptor) is known to be involved in learning and memory. We evaluated for the first time the quantification of a novel 5-HT(4) receptor radioligand, (11)C-SB207145, for in vivo brain imaging with PET in humans. METHODS For evaluation of reproducibility, 6 subjects were scanned twice with (11)C-SB207145 on the same day. A further 2 subjects were scanned before and after blocking with the selective 5-HT(4) receptor inverse agonist piboserod (SB207266). Arterial blood samples were drawn for the calculation of metabolite-corrected arterial input functions. Regions of interest were delineated automatically on the individual's MR images coregistered to the PET images, and regional time-activity curves were extracted. Quantitative tracer kinetic modeling was investigated with 1- and 2-tissue-compartment models using plasma input functions and the simplified reference tissue model (SRTM). RESULTS (11)C-SB207145 readily entered the brain and showed a distribution consistent with the known localization of the 5-HT(4) receptor. Using plasma input models, the time-activity data were well described by the 2-tissue-compartment model in all regions and allowed for the estimate of binding potentials relative to the reference region (BP(ND): striatum, 3.38 +/- 0.72; hippocampus, 0.82 +/- 0.19; parietal cortex, 0.30 +/- 0.08). Quantification with the 1-tissue-compartment model, 2-tissue-compartment model, and SRTM were associated with good test-retest reproducibility and time stability. However, the SRTM-generated BP(ND) values in the striatum were underestimated by 20%-43% in comparison to the 2-tissue-compartment model. The blocking study with piboserod confirmed that the radioligand was selective for the 5-HT(4) receptor, that the cerebellum was a suitable reference region devoid of specific binding, and that nonspecific binding was constant across brain regions. CONCLUSION In vivo imaging of cerebral 5-HT(4) receptors can be determined reliably using (11)C-207145 PET with arterial input in humans. SRTM showed high reproducibility and reliability but bias in the striatum, and therefore, the use of SRTM should be considered carefully for individual applications.
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Affiliation(s)
- Lisbeth Marner
- Neurobiology Research Unit, Neuroscience Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
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Russo O, Cachard-Chastel M, Rivière C, Giner M, Soulier JL, Berthouze M, Richard T, Monti JP, Sicsic S, Lezoualc'h F, Berque-Bestel I. Design, synthesis, and biological evaluation of new 5-HT4 receptor agonists: application as amyloid cascade modulators and potential therapeutic utility in Alzheimer's disease. J Med Chem 2009; 52:2214-25. [PMID: 19334715 DOI: 10.1021/jm801327q] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Serotonin 5-HT(4) receptor (5-HT(4)R) agonists are of particular interest for the treatment of Alzheimer's disease because of their ability to ameliorate cognitive deficits and to modulate production of amyloid beta-protein (Abeta). However, despite the range of 5-HT(4)R agonists synthesized to date, potent and selective 5-HT(4)R agonists are still lacking. In the present study, two libraries of molecules based on the scaffold of ML10302, a highly specific and partial 5-HT(4)R agonist, were efficiently prepared by parallel supported synthesis and their binding affinities and agonist activities evaluated. Furthermore, we showed that, in vivo, the two best candidates exhibited neuroprotective activity by increasing the level of the soluble form of the amyloid precursor protein (sAPPalpha) in the cortex and hippocampus of mice. Interestingly, one of these compounds could also inhibit Abeta fibril formation in vitro.
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Affiliation(s)
- Olivier Russo
- CNRS UMR C 8076 (BioCIS), Molecules Fluorees et Chimie Medicinale, UMR-S769, EA3544, Serotonine et Neuropharmacologie, IFR-141, Faculte de Pharmacie, Universite Paris-Sud, F- 92296 Chatenay-Malabry, France
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Bockaert J, Claeysen S, Compan V, Dumuis A. 5-HT(4) receptors: history, molecular pharmacology and brain functions. Neuropharmacology 2008; 55:922-31. [PMID: 18603269 DOI: 10.1016/j.neuropharm.2008.05.013] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 05/07/2008] [Accepted: 05/09/2008] [Indexed: 11/17/2022]
Abstract
Twenty years ago, we started the characterization of a 5-HT receptor coupled to cAMP production in neurons. This receptor obviously had a different pharmacology to the other 5-HT receptors described at that time, i.e. the 5-HT(1), 5-HT(2), 5-HT(3) receptors. We proposed to name it the 5-HT(4) receptor. Nowadays, 5-HT(4) receptors are one of the most studied GPCRs belonging to the "rhodopsin" family. Thanks to the existence of a great variety of ligands with inverse agonist, partial agonist, agonist and antagonist profiles, the pharmacological and physiological properties of this receptor are beginning to emerge. Although some 5-HT(4) partial agonists have been on the market for gastro-intestinal pathologies, 5-HT(4) receptor drugs have still to be commercialized for brain disorders. However, since 5-HT(4) receptors have recognized effects on memory, depression and feeding in animal models, there is still hope for a therapeutic destiny of this interesting target in brain disorders.
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Affiliation(s)
- Joël Bockaert
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France.
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Robert SJ, Lezoualc’h F. Distinct Functional Effects of Human 5-HT 4 Receptor Isoforms on β-Amyloid Secretion. NEURODEGENER DIS 2008; 5:163-5. [DOI: 10.1159/000113691] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Zaldua N, Gastineau M, Hoshino M, Lezoualc'h F, Zugaza JL. Epac signaling pathway involves STEF, a guanine nucleotide exchange factor for Rac, to regulate APP processing. FEBS Lett 2007; 581:5814-8. [PMID: 18047838 DOI: 10.1016/j.febslet.2007.11.053] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Revised: 11/06/2007] [Accepted: 11/16/2007] [Indexed: 01/13/2023]
Abstract
The amyloid precursor protein (APP) is a key protein involved in the development of Alzheimer's disease. We previously identified a signal transduction secretory pathway in which the small G protein Rac sets downstream of the cAMP/Epac/Rap1 signalling cascade regulating the alpha cleavage of APP [Maillet, M. et al. (2003) Crosstalk between Rap and Rac regulates secretion of sAPP alpha. Nat. Cell Biol. 5, 633-639]. We now report that Rap1 can physically and specifically associate with the guanine nucleotide exchange factor (GEF) STEF through its TSS region. A deleted TSS domain of STEF cells fails to activate Rac1 and dramatically decreases secretion of the non-amyloidogenic soluble form of APP (sAPP alpha) induced by the cAMP-binding protein Epac. Altogether, our data show that upon Epac activation, Rap1 recruits STEF through its TSS region and activates Rac1, which mediates APP processing.
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Affiliation(s)
- Natalia Zaldua
- Department of Proteomic, CIC bioGUNE, Parque Tecnológico de Bizkaia, Edificio 801A, 48160 Derio, Bizkaia, Spain
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Mohler EG, Shacham S, Noiman S, Lezoualc'h F, Robert S, Gastineau M, Rutkowski J, Marantz Y, Dumuis A, Bockaert J, Gold PE, Ragozzino ME. VRX-03011, a novel 5-HT4 agonist, enhances memory and hippocampal acetylcholine efflux. Neuropharmacology 2007; 53:563-73. [PMID: 17692343 DOI: 10.1016/j.neuropharm.2007.06.016] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 06/11/2007] [Accepted: 06/20/2007] [Indexed: 11/18/2022]
Abstract
Recent evidence suggests that 5-hydroxytryptamine (5-HT)(4) receptor activity enhances cognition and provides neuroprotection. Here we report the effects of VRX-03011, a novel partial 5-HT(4) agonist, that is both potent (K(i) approximately 30 nM) and highly selective (K(i) > 5 microM for all other 5-HT receptors tested). In separate experiments, rats received VRX-03011 (0.1-10 mg/kg i.p.) 30 min prior to spontaneous alternation testing in a no-delay or a 30-s delay condition. VRX-03011 (1, 5 and 10 mg/kg, but not 0.1 mg/kg) significantly enhanced delayed spontaneous alternation performance while none of the doses enhanced performance in the no-delay test. VRX-03011 (1 and 5 mg/kg) concomitantly enhanced hippocampal acetylcholine output and delayed spontaneous alternation scores compared to that of vehicle controls, but had no effect on hippocampal acetylcholine release under a resting condition. Moreover, suboptimal doses of VRX-03011 and the acetylcholinesterase inhibitor galanthamine combined to enhance memory. VRX-03011 also regulated amyloid precursor protein (APP) metabolism by inducing a concentration-dependent increase in the non-amyloidogenic soluble form of APP (sAPPalpha) with an EC(50) approximately 1--10 nM. VRX-03011 had no effect on contractile properties in guinea pig ileum or colon preparations with an EC(50) > 10 microM and did not alter rat intestinal transit at doses up to 10 mg/kg. These findings suggest that VRX-03011 may represent a novel treatment for Alzheimer's disease that reduces cognitive impairments and provides neuroprotection without gastrointestinal side effects.
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Affiliation(s)
- Eric G Mohler
- Department of Psychology, University of Illinois at Chicago, Chicago, IL 60607, USA
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Lezoualc'h F. 5-HT4 receptor and Alzheimer's disease: The amyloid connection. Exp Neurol 2007; 205:325-9. [PMID: 17346704 DOI: 10.1016/j.expneurol.2007.02.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2006] [Revised: 01/30/2007] [Accepted: 02/01/2007] [Indexed: 11/21/2022]
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