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Matsoukas MT, Panagiotopoulos V, Karageorgos V, Chrousos GP, Venihaki M, Liapakis G. Structural and Functional Insights into CRF Peptides and Their Receptors. BIOLOGY 2024; 13:120. [PMID: 38392338 PMCID: PMC10886364 DOI: 10.3390/biology13020120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/02/2024] [Accepted: 02/09/2024] [Indexed: 02/24/2024]
Abstract
Corticotropin-releasing factor or hormone (CRF or CRH) and the urocortins regulate a plethora of physiological functions and are involved in many pathophysiological processes. CRF and urocortins belong to the family of CRF peptides (CRF family), which includes sauvagine, urotensin, and many synthetic peptide and non-peptide CRF analogs. Several of the CRF analogs have shown considerable therapeutic potential in the treatment of various diseases. The CRF peptide family act by interacting with two types of plasma membrane proteins, type 1 (CRF1R) and type 2 (CRF2R), which belong to subfamily B1 of the family B G-protein-coupled receptors (GPCRs). This work describes the structure of CRF peptides and their receptors and the activation mechanism of the latter, which is compared with that of other GPCRs. It also discusses recent structural information that rationalizes the selective binding of various ligands to the two CRF receptor types and the activation of receptors by different agonists.
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Affiliation(s)
- Minos-Timotheos Matsoukas
- Department of Biomedical Engineering, School of Engineering, University of West Attica, 12243 Athens, Greece
| | - Vasilis Panagiotopoulos
- Department of Biomedical Engineering, School of Engineering, University of West Attica, 12243 Athens, Greece
| | - Vlasios Karageorgos
- Department of Pharmacology, Faculty of Medicine, University of Crete, 71003 Heraklion, Greece
| | - George P Chrousos
- University Research Institute of Maternal and Child Health and Precision Medicine and UNESCO, National and Kapodistrian University of Athens, Livadias 8, 11527 Athens, Greece
| | - Maria Venihaki
- Department of Clinical Chemistry, Faculty of Medicine, University of Crete, 71003 Heraklion, Greece
| | - George Liapakis
- Department of Pharmacology, Faculty of Medicine, University of Crete, 71003 Heraklion, Greece
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Hafenbreidel M, Pandey S, Briggs SB, Arza M, Bonthu S, Fisher C, Tiller A, Hall AB, Reed S, Mayorga N, Lin L, Khan S, Cameron MD, Rumbaugh G, Miller CA. Basolateral amygdala corticotropin releasing factor receptor 2 interacts with nonmuscle myosin II to destabilize memory in males. Neurobiol Learn Mem 2023; 206:107865. [PMID: 37995804 DOI: 10.1016/j.nlm.2023.107865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/24/2023] [Accepted: 11/20/2023] [Indexed: 11/25/2023]
Abstract
Preclinical studies show that inhibiting the actin motor ATPase nonmuscle myosin II (NMII) with blebbistatin (Blebb) in the basolateral amgydala (BLA) depolymerizes actin, resulting in an immediate, retrieval-independent disruption of methamphetamine (METH)-associated memory in male and female adult and adolescent rodents. The effect is highly selective, as NMII inhibition has no effect in other relevant brain regions (e.g., dorsal hippocampus [dPHC], nucleus accumbens [NAc]), nor does it interfere with associations for other aversive or appetitive stimuli, including cocaine (COC). To understand the mechanisms responsible for drug specific selectivity we began by investigating, in male mice, the pharmacokinetic differences in METH and COC brain exposure . Replicating METH's longer half-life with COC did not render the COC association susceptible to disruption by NMII inhibition. Therefore, we next assessed transcriptional differences. Comparative RNA-seq profiling in the BLA, dHPC and NAc following METH or COC conditioning identified crhr2, which encodes the corticotropin releasing factor receptor 2 (CRF2), as uniquely upregulated by METH in the BLA. CRF2 antagonism with Astressin-2B (AS2B) had no effect on METH-associated memory after consolidation, allowing for determination of CRF2 influences on NMII-based susceptibility. Pretreatment with AS2B prevented the ability of Blebb to disrupt an established METH-associated memory. Alternatively, combining CRF2 overexpression and agonist treatment, urocortin 3 (UCN3), in the BLA during conditioning rendered COC-associated memory susceptible to disruption by NMII inhibition, mimicking the Blebb-induced, retrieval-independent memory disruption seen with METH. These results suggest that BLA CRF2 receptor activation during memory formation in male mice can prevent stabilization of the actin-myosin cytoskeleton supporting the memory, rendering it vulnerable to disruption by NMII inhibition. CRF2 represents an interesting target for BLA-dependent memory destabilization via downstream effects on NMII.
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Affiliation(s)
- Madalyn Hafenbreidel
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Surya Pandey
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Sherri B Briggs
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Meghana Arza
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Shalakha Bonthu
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Cadence Fisher
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Annika Tiller
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Alice B Hall
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Shayna Reed
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Natasha Mayorga
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Li Lin
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Susan Khan
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Michael D Cameron
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Gavin Rumbaugh
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States
| | - Courtney A Miller
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, United States; The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL 33458, United States.
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3
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Hafenbreidel M, Briggs SB, Arza M, Bonthu S, Fisher C, Tiller A, Hall AB, Reed S, Mayorga N, Lin L, Khan S, Cameron MD, Rumbaugh G, Miller CA. Basolateral Amygdala Corticotrophin Releasing Factor Receptor 2 Interacts with Nonmuscle Myosin II to Destabilize Memory. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.22.541732. [PMID: 37292925 PMCID: PMC10245849 DOI: 10.1101/2023.05.22.541732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Inhibiting the actin motor ATPase nonmuscle myosin II (NMII) with blebbistatin (Blebb) in the basolateral amgydala (BLA) depolymerizes actin, resulting in an immediate, retrieval-independent disruption of methamphetamine (METH)-associated memory. The effect is highly selective, as NMII inhibition has no effect in other relevant brain regions (e.g. dorsal hippocampus [dPHC], nucleus accumbens [NAc]), nor does it interfere with associations for other aversive or appetitive stimuli, including cocaine (COC). To investigate a potential source of this specificity, pharmacokinetic differences in METH and COC brain exposure were examined. Replicating METH's longer half-life with COC did not render the COC association susceptible to disruption by NMII inhibition. Therefore, transcriptional differences were next assessed. Comparative RNA-seq profiling in the BLA, dHPC and NAc following METH or COC conditioning identified crhr2, which encodes the corticotrophin releasing factor receptor 2 (CRF2), as uniquely upregulated by METH in the BLA. CRF2 antagonism with Astressin-2B (AS2B) had no effect on METH-associated memory after consolidation, allowing for determination of CRF2 influences on NMII-based susceptibility after METH conditioning. Pretreatment with AS2B occluded the ability of Blebb to disrupt an established METH-associated memory. Alternatively, the Blebb-induced, retrieval-independent memory disruption seen with METH was mimicked for COC when combined with CRF2 overexpression in the BLA and its ligand, UCN3 during conditioning. These results indicate that BLA CRF2 receptor activation during learning can prevent stabilization of the actin-myosin cytoskeleton supporting the memory, rendering it vulnerable to disruption via NMII inhibition. CRF2 represents an interesting target for BLA-dependent memory destabilization via downstream effects on NMII.
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Affiliation(s)
- Madalyn Hafenbreidel
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Sherri B Briggs
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Meghana Arza
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Shalakha Bonthu
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Cadence Fisher
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Annika Tiller
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
- Present address: Department of Physiology and Neuroscience, Medical University of South Carolina, Charleston, SC, 29464
| | - Alice B Hall
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Shayna Reed
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Natasha Mayorga
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Li Lin
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
| | - Susan Khan
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
| | - Michael D Cameron
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
| | - Gavin Rumbaugh
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
| | - Courtney A Miller
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, 33458
- Present address: Department of Molecular Medicine, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, 33458
- Present address: Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology Jupiter, FL, 33458
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Amado P, Zegers J, Yarur HE, Gysling K. Transcriptional Regulation, Signaling Pathways, and Subcellular Localization of Corticotropin-Releasing Factor Receptors in the Central Nervous System. Mol Pharmacol 2022; 102:280-287. [PMID: 36167424 DOI: 10.1124/molpharm.121.000476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 09/12/2022] [Indexed: 12/24/2022] Open
Abstract
Corticotropin-releasing factor (CRF) receptors CRF-R1 and CRF-R2 are differentially distributed in body tissues, and although they respond differentially to stimuli due to their association with different signaling pathways, both receptors have a fundamental role in the response and adaptation to stressful stimuli. Here, we summarize the reported data on different forms of CRF-R1 and CRF-R2 regulation as well as on their subcellular localization. Although the presence of R1 has been described at pre- and postsynaptic sites, R2 is mainly associated with postsynaptic densities. Different studies have provided valuable information on how these receptors regulate responses at a central level, elucidating different and sometimes synergistic roles in response to stress, but despite their high sequence identity, both receptors have been described to be differentially regulated both by their ligands and by transcriptional factors. To date, and from the point of view of their promoter sequences, it has not yet been reported how the different consensus sites identified in silico could be modulating the transcriptional regulation and expression of the receptors under different conditions, which strongly limits the full understanding of their differential functions, providing a wide field to increase and expand the study of the regulation and role of CRF receptors in the CRF system. SIGNIFICANCE STATEMENT: A large number of physiological functions related to the organization of the stress response in different body tissues are associated with the corticotropin-releasing factor system. This system also plays a relevant role in depression and anxiety disorders, as well as being a direct connection between stress and addiction. A better understanding of how the receptors of this system are regulated would help to expand the understanding of how these receptors respond differently to both drugs and stressful stimuli.
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Affiliation(s)
- Paula Amado
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Zegers
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Hector E Yarur
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Katia Gysling
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
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Discovery of a stable tripeptide targeting the N-domain of CRF1 receptor. Amino Acids 2020; 52:1337-1351. [PMID: 32996057 DOI: 10.1007/s00726-020-02895-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 09/19/2020] [Indexed: 10/23/2022]
Abstract
The corticotropin-releasing factor (CRF) and its CRF1 receptor (CRF1R) play a central role in the maintenance of homeostasis. Malfunctioning of the CRF/CRF1R unit is associated with several disorders, such as anxiety and depression. Non-peptide CRF1R-selective antagonists have been shown to exert anxiolytic and antidepressant effects on experimental animals. However, none of them is in clinical use today because of several side effects, thus demonstrating the need for the development of other more suitable CRF1R antagonists. In an effort to develop novel CRF1R antagonists we designed, synthesized and chemically characterized two tripeptide analogues of CRF, namely (R)-LMI and (S)-LMI, having their Leu either in R (or D) or in S (or L) configuration, respectively. Their design was based on the crystal structure of the N-extracellular domain (N-domain) of CRF1R/CRF complex, using a relevant array of computational methods. Experimental evaluation of the stability of synthetic peptides in human plasma has revealed that (R)-LMI is proteolytically more stable than (S)-LMI. Based on this finding, (R)-LMI was selected for pharmacological characterization. We have found that (R)-LMI is a CRF antagonist, inhibiting (1) the CRF-stimulated accumulation of cAMP in HEK 293 cells expressing the CRF1R, (2) the production of interleukins by adipocytes and (3) the proliferation rate of RAW 264.7 cells. (R)-LMI likely blocked agonist actions by interacting with the N-domain of CRF1R as suggested by data using a constitutively active chimera of CRF1R. We propose that (R)-LMI can be used as an optimal lead compound in the rational design of novel CRF antagonists.
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Romero-Leguizamón CR, Kohlmeier KA. Stress-related endogenous neuropeptides induce neuronal excitation in the Laterodorsal Tegmentum. Eur Neuropsychopharmacol 2020; 38:86-97. [PMID: 32768153 DOI: 10.1016/j.euroneuro.2020.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 05/29/2020] [Accepted: 07/16/2020] [Indexed: 01/07/2023]
Abstract
Stress is a physiological response that promotes maintenance of balance against harmful stimuli. Unfortunately, chronic activation of stress systems facilitates the development of psychiatric disorders. A stress-mediated hypercholinergic state could underlie this facilitation, as cholinergic mechanisms have been suggested to play a role in anxiety, depression, and substance use disorder (SUD). Stimulation by stress hormones, urocortin (Ucn1) or corticotropin-releasing factor (CRF), of the CRF receptor type 1 (CRFR1) of acetylcholine-containing neurons of the laterodorsal tegmental nucleus (LDT) could be involved in modulation of cholinergic transmission during periods of stress hormone activation, which could play a role in psychiatric disorders as cholinergic LDT neurons project to, and control activity in, mood-, arousal- and SUD-controlling regions. The present study investigated for the first time the membrane effects and intracellular outcomes of CRFR1 activation by endogenous stress hormones on LDT neurons. Patch clamp recordings of immunohistochemically-identified cholinergic and non-cholinergic LDT neurons with concurrent calcium imaging were used to monitor cellular responses to CRFR1 stimulation with Ucn1 and CRF. Postsynaptically-mediated excitatory currents were elicited in LDT cholinergic neurons, accompanied by an enhancement in synaptic events. In addition, CRFR1 activation resulted in rises in intracellular calcium levels. CRFR1 stimulation recruited MAPK/ERK and SERCA-ATPase involved pathways. The data presented here provide the first evidence that Ucn1 and CRF exert pre and postsynaptic excitatory membrane actions on LDT cholinergic neurons that could underlie the hypercholinergic state associated with stress which could play a role in the heightened risk of psychiatric disorders associated with a chronic stress state.
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Affiliation(s)
- Cesar R Romero-Leguizamón
- Department of Drug Design and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Kristi A Kohlmeier
- Department of Drug Design and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, 2100, Denmark.
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Vandael D, Gounko NV. Corticotropin releasing factor-binding protein (CRF-BP) as a potential new therapeutic target in Alzheimer's disease and stress disorders. Transl Psychiatry 2019; 9:272. [PMID: 31641098 PMCID: PMC6805916 DOI: 10.1038/s41398-019-0581-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 07/30/2019] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease is the most common cause of dementia and one of the most complex human neurodegenerative diseases. Numerous studies have demonstrated a critical role of the environment in the pathogenesis and pathophysiology of the disease, where daily life stress plays an important role. A lot of epigenetic studies have led to the conclusion that chronic stress and stress-related disorders play an important part in the onset of neurodegenerative disorders, and an enormous amount of research yielded valuable discoveries but has so far not led to the development of effective treatment strategies for Alzheimer's disease. Corticotropin-releasing factor (CRF) is one of the major hormones and at the same time a neuropeptide acting in stress response. Deregulation of protein levels of CRF is involved in the pathogenesis of Alzheimer's disease, but little is known about the precise roles of CRF and its binding protein, CRF-BP, in neurodegenerative diseases. In this review, we summarize the key evidence for and against the involvement of stress-associated modulation of the CRF system in the pathogenesis of Alzheimer's disease and discuss how recent findings could lead to new potential treatment possibilities in Alzheimer's disease by using CRF-BP as a therapeutic target.
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Affiliation(s)
- Dorien Vandael
- VIB-KU Leuven Center for Brain and Disease Research, Electron Microscopy Platform, Herestraat 49, B-3000 Leuven, Belgium ,VIB Bioimaging Core Facility, Herestraat 49, B-3000 Leuven, Belgium ,KU Leuven Department of Neurosciences, Leuven Brain Institute, Herestraat 49, B-3000 Leuven, Belgium
| | - Natalia V. Gounko
- VIB-KU Leuven Center for Brain and Disease Research, Electron Microscopy Platform, Herestraat 49, B-3000 Leuven, Belgium ,VIB Bioimaging Core Facility, Herestraat 49, B-3000 Leuven, Belgium ,KU Leuven Department of Neurosciences, Leuven Brain Institute, Herestraat 49, B-3000 Leuven, Belgium
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Seidel L, Zarzycka B, Katritch V, Coin I. Exploring Pairwise Chemical Crosslinking To Study Peptide-Receptor Interactions. Chembiochem 2019; 20:683-692. [PMID: 30565820 DOI: 10.1002/cbic.201800582] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Indexed: 01/29/2023]
Abstract
Pairwise crosslinking is a powerful technique to characterize interactions between G protein coupled receptors and their ligands in the live cell. In this work, the "thiol trapping" method, which exploits the proximity-enhanced reaction between haloacetamides and cysteine, is examined to identify intermolecular pairs of vicinal positions. By incorporating cysteine into the corticotropin-releasing factor receptor and either α-chloro- or α-bromoacetamide groups into its ligands, it is shown that thiol trapping provides highly reproducible signals and a low background, and represents a valid alternative to classical "disulfide trapping". The method is advantageous if reducing agents are required during sample analysis. Moreover, it can provide partially distinct spatial constraints, thus giving access to a wider dataset for molecular modeling. Finally, by applying recombinant mini-Gs, GTPγS, and Gαs-depleted HEK293 cells to modulate Gs coupling, it is shown that yields of crosslinking increase in the presence of elevated levels of Gs.
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Affiliation(s)
- Lisa Seidel
- Faculty of Life Sciences, Institute of Biochemistry, University of Leipzig, Bruederstrasse 34, 04103, Leipzig, Germany
| | - Barbara Zarzycka
- Department of Biological Sciences, Bridge Institute, University of Southern California, 1002 Childs Way, MCB 317, Los Angeles, CA, 90089-3502, USA
| | - Vsevolod Katritch
- Department of Biological Sciences, Bridge Institute, University of Southern California, 1002 Childs Way, MCB 317, Los Angeles, CA, 90089-3502, USA.,Department of Chemistry, Bridge Institute, University of Southern California, 1002 Childs Way, MCB 317, Los Angeles, CA, 90089-3502, USA
| | - Irene Coin
- Faculty of Life Sciences, Institute of Biochemistry, University of Leipzig, Bruederstrasse 34, 04103, Leipzig, Germany
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Deussing JM, Chen A. The Corticotropin-Releasing Factor Family: Physiology of the Stress Response. Physiol Rev 2018; 98:2225-2286. [DOI: 10.1152/physrev.00042.2017] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The physiological stress response is responsible for the maintenance of homeostasis in the presence of real or perceived challenges. In this function, the brain activates adaptive responses that involve numerous neural circuits and effector molecules to adapt to the current and future demands. A maladaptive stress response has been linked to the etiology of a variety of disorders, such as anxiety and mood disorders, eating disorders, and the metabolic syndrome. The neuropeptide corticotropin-releasing factor (CRF) and its relatives, the urocortins 1–3, in concert with their receptors (CRFR1, CRFR2), have emerged as central components of the physiological stress response. This central peptidergic system impinges on a broad spectrum of physiological processes that are the basis for successful adaptation and concomitantly integrate autonomic, neuroendocrine, and behavioral stress responses. This review focuses on the physiology of CRF-related peptides and their cognate receptors with the aim of providing a comprehensive up-to-date overview of the field. We describe the major molecular features covering aspects of gene expression and regulation, structural properties, and molecular interactions, as well as mechanisms of signal transduction and their surveillance. In addition, we discuss the large body of published experimental studies focusing on state-of-the-art genetic approaches with high temporal and spatial precision, which collectively aimed to dissect the contribution of CRF-related ligands and receptors to different levels of the stress response. We discuss the controversies in the field and unravel knowledge gaps that might pave the way for future research directions and open up novel opportunities for therapeutic intervention.
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Affiliation(s)
- Jan M. Deussing
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany; and Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Alon Chen
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany; and Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
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10
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Karageorgos V, Venihaki M, Sakellaris S, Pardalos M, Kontakis G, Matsoukas MT, Gravanis A, Margioris A, Liapakis G. Current understanding of the structure and function of family B GPCRs to design novel drugs. Hormones (Athens) 2018; 17:45-59. [PMID: 29858864 DOI: 10.1007/s42000-018-0009-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 01/25/2018] [Indexed: 01/10/2023]
Abstract
Family B of G-protein-coupled receptors (GPCRs) and their ligands play a central role in a number of homeostatic mechanisms in the endocrine, gastrointestinal, skeletal, immune, cardiovascular and central nervous systems. Alterations in family B GPCR-regulated homeostatic mechanisms may cause a variety of potentially life-threatening conditions, signifying the necessity to develop novel ligands targeting these receptors. Obtaining structural and functional information on family B GPCRs will accelerate the development of novel drugs to target these receptors. Family B GPCRs are proteins that span the plasma membrane seven times, thus forming seven transmembrane domains (TM1-TM7) which are connected to each other by three extracellular (EL) and three intracellular (IL) loops. In addition, these receptors have a long extracellular N-domain and an intracellular C-tail. The upper parts of the TMs and ELs form the J-domain of receptors. The C-terminal region of peptides first binds to the N-domain of receptors. This 'first-step' interaction orients the N-terminal region of peptides towards the J-domain of receptors, thus resulting in a 'second-step' of ligand-receptor interaction that activates the receptor. Activation-associated structural changes of receptors are transmitted through TMs to their intracellular regions and are responsible for their interaction with the G proteins and activation of the latter, thus resulting in a biological effect. This review summarizes the current information regarding the structure and function of family B GPCRs and their physiological and pathophysiological roles.
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Affiliation(s)
- Vlasios Karageorgos
- Department of Pharmacology, School of Medicine, University of Crete, Voutes, 71003, Heraklion, Crete, Greece
| | - Maria Venihaki
- Department of Clinical Chemistry, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Stelios Sakellaris
- Department of Pharmacology, School of Medicine, University of Crete, Voutes, 71003, Heraklion, Crete, Greece
| | - Michail Pardalos
- Department of Pharmacology, School of Medicine, University of Crete, Voutes, 71003, Heraklion, Crete, Greece
| | - George Kontakis
- Department of Orthopedics, University Hospital of Heraklion, Crete, Greece
| | | | - Achille Gravanis
- Department of Pharmacology, School of Medicine, University of Crete, Voutes, 71003, Heraklion, Crete, Greece
| | - Andreas Margioris
- Department of Clinical Chemistry, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - George Liapakis
- Department of Pharmacology, School of Medicine, University of Crete, Voutes, 71003, Heraklion, Crete, Greece.
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11
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Seidel L, Zarzycka B, Zaidi SA, Katritch V, Coin I. Structural insight into the activation of a class B G-protein-coupled receptor by peptide hormones in live human cells. eLife 2017; 6. [PMID: 28771403 PMCID: PMC5542768 DOI: 10.7554/elife.27711] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 07/17/2017] [Indexed: 12/22/2022] Open
Abstract
The activation mechanism of class B G-protein-coupled receptors (GPCRs) remains largely unknown. To characterize conformational changes induced by peptide hormones, we investigated interactions of the class B corticotropin-releasing factor receptor type 1 (CRF1R) with two peptide agonists and three peptide antagonists obtained by N-truncation of the agonists. Surface mapping with genetically encoded photo-crosslinkers and pair-wise crosslinking revealed distinct footprints of agonists and antagonists on the transmembrane domain (TMD) of CRF1R and identified numerous ligand-receptor contact sites, directly from the intact receptor in live human cells. The data enabled generating atomistic models of CRF- and CRF(12-41)-bound CRF1R, further explored by molecular dynamics simulations. We show that bound agonist and antagonist adopt different folds and stabilize distinct TMD conformations, which involves bending of helices VI and VII around flexible glycine hinges. Conservation of these glycine hinges among all class B GPCRs suggests their general role in activation of these receptors. DOI:http://dx.doi.org/10.7554/eLife.27711.001
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Affiliation(s)
- Lisa Seidel
- Institute of Biochemistry, Leipzig University, Leipzig, Germany
| | - Barbara Zarzycka
- Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, United States
| | - Saheem A Zaidi
- Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, United States
| | - Vsevolod Katritch
- Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, United States.,Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, United States
| | - Irene Coin
- Institute of Biochemistry, Leipzig University, Leipzig, Germany
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12
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Futch HS, Croft CL, Truong VQ, Krause EG, Golde TE. Targeting psychologic stress signaling pathways in Alzheimer's disease. Mol Neurodegener 2017; 12:49. [PMID: 28633663 PMCID: PMC5479037 DOI: 10.1186/s13024-017-0190-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 06/08/2017] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's Disease (AD) is the most prevalent progressive neurodegenerative disease; to date, no AD therapy has proven effective in delaying or preventing the disease course. In the search for novel therapeutic targets in AD, it has been shown that increased chronic psychologic stress is associated with AD risk. Subsequently, biologic pathways underlying psychologic stress have been identified and shown to be able to exacerbate AD relevant pathologies. In this review, we summarize the literature relevant to the association between psychologic stress and AD, focusing on studies investigating the effects of stress paradigms on transgenic mouse models of Amyloid-β (Aβ) and tau pathologies. In recent years, a substantial amount of research has been done investigating a key stress-response mediator, corticotropin-releasing hormone (CRH), and its interactions with AD relevant processes. We highlight attempts to target the CRH signaling pathway as a therapeutic intervention in these transgenic mouse models and discuss how targeting this pathway is a promising avenue for further investigation.
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Affiliation(s)
- Hunter S. Futch
- Department of Neuroscience, University of Florida, Gainesville, FL 32610 USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32610 USA
- McKnight Brain Institute, University of Florida, 1149 Newell Drive, PO Box 1000015, Gainesville, FL 32610 USA
| | - Cara L. Croft
- Department of Neuroscience, University of Florida, Gainesville, FL 32610 USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32610 USA
- McKnight Brain Institute, University of Florida, 1149 Newell Drive, PO Box 1000015, Gainesville, FL 32610 USA
| | - Van Q. Truong
- Department of Neuroscience, University of Florida, Gainesville, FL 32610 USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32610 USA
- McKnight Brain Institute, University of Florida, 1149 Newell Drive, PO Box 1000015, Gainesville, FL 32610 USA
| | - Eric G. Krause
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, USA
- McKnight Brain Institute, University of Florida, 1149 Newell Drive, PO Box 1000015, Gainesville, FL 32610 USA
| | - Todd E. Golde
- Department of Neuroscience, University of Florida, Gainesville, FL 32610 USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32610 USA
- McKnight Brain Institute, University of Florida, 1149 Newell Drive, PO Box 1000015, Gainesville, FL 32610 USA
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13
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The blockage of ventromedial hypothalamus CRF type 2 receptors impairs escape responses in the elevated T-maze. Behav Brain Res 2017; 329:41-50. [DOI: 10.1016/j.bbr.2017.04.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/17/2017] [Indexed: 11/20/2022]
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14
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P7, a novel antagonist of corticotropin releasing factor receptor type 1 (CRFR1) screened from phage display library. Biochem Biophys Res Commun 2015; 463:200-4. [PMID: 25998380 DOI: 10.1016/j.bbrc.2015.05.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 05/08/2015] [Indexed: 11/23/2022]
Abstract
The corticotropin releasing factor (CRF) plays a central role in regulating the activities of hypothalamic-pituitary-adrenal (HPA) axis in the presence of a variety of stressful stimuli via binding to its type 1 receptors (CRFR1). Despite that many peptidic or non-peptidic antagonists of CRFR1 have been developed to serve as therapeutic tools to CRF-related pathologies, none of them have been utilized clinically. Targeting the extracellular domain 1 (EC1) of CRFR1, the CRF-binding site, represents a new strategy to inhibit the function of the receptor. However, no such agents have been identified up to now. Herein, by using an 87-amino acid fragment corresponding to the EC1 region as the bait, we screened the binding polypeptides from a phage display (Ph.D.-12) peptide library. After 3-round biopanning, positive clones were selected and the polypeptides carried by them were identified. 5 polypeptides were found to bind with the target specifically. Among them, the P7 exhibited the highest affinity. By evaluating the cAMP accumulation in the CRFR1 or CRFR2-expressing HEK293 cells, we demonstrated that P7 blocking the function of CRFR1, but not CRFR2. In addition, we also found that P7 and CRF act on CRFR1 competitively. Taken together, we reveal that P7, a novel polypeptide identified from phage display library, inhibits the function of CRFR1 effectively and specifically by binding at its EC1 domain. The new polypeptide might provide a promising agent for diagnostic or therapeutic utilities in CRF-related disorders.
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15
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Park HJ, Ran Y, Jung JI, Holmes O, Price AR, Smithson L, Ceballos-Diaz C, Han C, Wolfe MS, Daaka Y, Ryabinin AE, Kim SH, Hauger RL, Golde TE, Felsenstein KM. The stress response neuropeptide CRF increases amyloid-β production by regulating γ-secretase activity. EMBO J 2015; 34:1674-86. [PMID: 25964433 DOI: 10.15252/embj.201488795] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 04/15/2015] [Indexed: 12/26/2022] Open
Abstract
The biological underpinnings linking stress to Alzheimer's disease (AD) risk are poorly understood. We investigated how corticotrophin releasing factor (CRF), a critical stress response mediator, influences amyloid-β (Aβ) production. In cells, CRF treatment increases Aβ production and triggers CRF receptor 1 (CRFR1) and γ-secretase internalization. Co-immunoprecipitation studies establish that γ-secretase associates with CRFR1; this is mediated by β-arrestin binding motifs. Additionally, CRFR1 and γ-secretase co-localize in lipid raft fractions, with increased γ-secretase accumulation upon CRF treatment. CRF treatment also increases γ-secretase activity in vitro, revealing a second, receptor-independent mechanism of action. CRF is the first endogenous neuropeptide that can be shown to directly modulate γ-secretase activity. Unexpectedly, CRFR1 antagonists also increased Aβ. These data collectively link CRF to increased Aβ through γ-secretase and provide mechanistic insight into how stress may increase AD risk. They also suggest that direct targeting of CRF might be necessary to effectively modulate this pathway for therapeutic benefit in AD, as CRFR1 antagonists increase Aβ and in some cases preferentially increase Aβ42 via complex effects on γ-secretase.
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Affiliation(s)
- Hyo-Jin Park
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA Department of Pharmacology and Therapeutics, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Yong Ran
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Joo In Jung
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Oliver Holmes
- Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Ashleigh R Price
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Lisa Smithson
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Carolina Ceballos-Diaz
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Chul Han
- Department of Aging and Geriatric Research, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Michael S Wolfe
- Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Yehia Daaka
- Department of Anatomy and Cell Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Andrey E Ryabinin
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, USA
| | - Seong-Hun Kim
- Department of Pharmacology and Therapeutics, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Richard L Hauger
- Center of Excellence for Stress and Mental Health, Department of Psychiatry, VA Healthcare System, University of California, San Diego, CA, USA
| | - Todd E Golde
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Kevin M Felsenstein
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
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16
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Carter PH, Dean T, Bhayana B, Khatri A, Rajur R, Gardella TJ. Actions of the small molecule ligands SW106 and AH-3960 on the type-1 parathyroid hormone receptor. Mol Endocrinol 2015; 29:307-21. [PMID: 25584411 DOI: 10.1210/me.2014-1129] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The parathyroid hormone receptor-1 (PTHR1) plays critical roles in regulating blood calcium levels and bone metabolism and is thus of interest for small-molecule ligand development. Of the few small-molecule ligands reported for the PTHR1, most are of low affinity, and none has a well-defined mechanism of action. Here, we show that SW106 and AH-3960, compounds previously identified to act as an antagonist and agonist, respectively, on the PTHR1, each bind to PTHR1-delNT, a PTHR1 construct that lacks the large amino-terminal extracellular domain used for binding endogenous PTH peptide ligands, with the same micromolar affinity with which it binds to the intact PTHR1. SW106 antagonized PTHR1-mediated cAMP signaling induced by the peptide analog, M-PTH(1-11), as well as by the native PTH(1-9) sequence, as tethered to the extracellular end of transmembrane domain (TMD) helix-1 of the receptor. SW106, however, did not function as an inverse agonist on either PTHR1-H223R or PTHR1-T410P, which have activating mutations at the cytoplasmic ends of TMD helices 2 and 6, respectively. The overall data indicate that SW106 and AH-3960 each bind to the PTHR1 TMD region and likely to within an extracellularly exposed area that is occupied by the N-terminal residues of PTH peptides. Additionally, they suggest that the inhibitory effects of SW106 are limited to the extracellular portions of the TMD region that mediate interactions with agonist ligands but do not extend to receptor-activation determinants situated more deeply in the helical bundle. The study helps to elucidate potential mechanisms of small-molecule binding at the PTHR1.
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Affiliation(s)
- Percy H Carter
- Endocrine Unit (T.D., A.K., T.J.G.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02492; Department of Photomedicine (B.B.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02492; CreaGen Biosciences, Inc (R.R.), Woburn, Massachusetts 01801; and Bristol-Myers Squibb Co (P.H.C.), Princeton, New Jersey 08543
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17
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Abstract
Corticotrophin-releasing hormone (CRH) is the pivotal neuroendocrine peptide hormone associated with the regulation of the stress response in vertebrates. However, CRH-like peptides are also found in a number of invertebrate species. The origin of this peptide can be traced to a common ancestor of lineages leading to chordates and to arthropods, postulated to occur some 500 million years ago. Evidence indicates the presence of a single CRH-like receptor and a soluble binding protein system that acted to transduce and regulate the actions of the early CRH peptide. In vertebrates, genome duplications led to the divergence of CRH receptors into CRH1 and CRH2 forms in tandem with the development of four paralogous ligand lineages that included CRH; urotensin I/urocortin (Ucn), Ucn2 and Ucn3. In addition, taxon-specific genome duplications led to further local divergences in CRH ligands and receptors. Functionally, the CRH ligand-receptor system evolved initially as a molecular system to integrate early diuresis and nutrient acquisition. As multicellular organisms evolved into more complex forms, this ligand-receptor system became integrated with the organismal stress response to coordinate homoeostatic challenges with internal energy usage. In vertebrates, CRH and the CRH1 receptor became associated with the hypothalamo-pituitary-adrenal/interrenal axis and the initial stress response, whereas the CRH2 receptor was selected to play a greater role in diuresis, nutrient acquisition and the latter aspects of the stress response.
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Affiliation(s)
- David A Lovejoy
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
| | - Belinda S W Chang
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, CanadaDepartment of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
| | - Nathan R Lovejoy
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
| | - Jon del Castillo
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
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18
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Zorrilla EP, Roberts AJ, Rivier JE, Koob GF. Anxiolytic-like effects of antisauvagine-30 in mice are not mediated by CRF2 receptors. PLoS One 2013; 8:e63942. [PMID: 24015170 PMCID: PMC3756045 DOI: 10.1371/journal.pone.0063942] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 04/09/2013] [Indexed: 11/18/2022] Open
Abstract
The role of brain corticotropin-releasing factor type 2 (CRF2) receptors in behavioral stress responses remains controversial. Conflicting findings suggest pro-stress, anti-stress or no effects of impeding CRF2 signaling. Previous studies have used antisauvagine-30 as a selective CRF2 antagonist. The present study tested the hypotheses that 1) potential anxiolytic-like actions of intracerebroventricular (i.c.v.) administration of antisauvagine-30 also are present in mice lacking CRF2 receptors and 2) potential anxiolytic-like effects of antisauvagine-30 are not shared by the more selective CRF2 antagonist astressin2-B. Cannulated, male CRF2 receptor knockout (n = 22) and wildtype littermate mice (n = 21) backcrossed onto a C57BL/6J genetic background were tested in the marble burying, elevated plus-maze, and shock-induced freezing tests following pretreatment (i.c.v.) with vehicle, antisauvagine-30 or astressin2-B. Antisauvagine-30 reduced shock-induced freezing equally in wildtype and CRF2 knockout mice. In contrast, neither astressin2-B nor CRF2 genotype influenced shock-induced freezing. Neither CRF antagonist nor CRF2 genotype influenced anxiety-like behavior in the plus-maze or marble burying tests. A literature review showed that the typical antisauvagine-30 concentration infused in previous intracranial studies (∼1 mM) was 3 orders greater than its IC50 to block CRF1-mediated cAMP responses and 4 orders greater than its binding constants (Kd, Ki) for CRF1 receptors. Thus, increasing, previously used doses of antisauvagine-30 also exert non-CRF2-mediated effects, perhaps via CRF1. The results do not support the hypothesis that brain CRF2 receptors tonically promote anxiogenic-like behavior. Utilization of CRF2 antagonists, such as astressin2-B, at doses that are more subtype-selective, can better clarify the significance of brain CRF2 systems in stress-related behavior.
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Affiliation(s)
- Eric P. Zorrilla
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, California, United States of America
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
- * E-mail: (EPZ); (GFK)
| | - Amanda J. Roberts
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jean E. Rivier
- The Clayton Foundation Laboratories for Peptide Biology and Structural Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - George F. Koob
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, California, United States of America
- * E-mail: (EPZ); (GFK)
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19
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Jones LH, Price DA. Medicinal chemistry of glucagon-like peptide receptor agonists. PROGRESS IN MEDICINAL CHEMISTRY 2013; 52:45-96. [PMID: 23384666 DOI: 10.1016/b978-0-444-62652-3.00002-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Lyn H Jones
- BioTherapeutics Chemistry, WorldWide Medicinal Chemistry, Pfizer, Cambridge, MA, USA
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20
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Valentino RJ, Bangasser D, Van Bockstaele EJ. Sex-biased stress signaling: the corticotropin-releasing factor receptor as a model. Mol Pharmacol 2012; 83:737-45. [PMID: 23239826 DOI: 10.1124/mol.112.083550] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Sex differences in the prevalence or severity of many diseases and in the response to pharmacological agents are well recognized. Elucidating the biologic bases of these differences can advance our understanding of the pathophysiology of disease and facilitate the development of treatments. Despite the importance to medicine, this has been an area of limited research. Here, we review physiologic, cellular, and molecular findings supporting the idea that there are sex differences in receptor signaling and trafficking that can be determinants of pathology. The focus is on the receptor for corticotropin-releasing factor (CRF), the orchestrator of the stress response, which has been implicated in diverse stress-related diseases that show a female prevalence. Data are reviewed that show sex differences in the association of the CRF receptor (CRF1) with the Gs protein and β-arrestin 2 that would render females more responsive to acute stress and less able to adapt to chronic stress as a result of compromised CRF1 internalization. Because β-arrestin 2 serves to link CRF1 to Gs-independent signaling pathways, this sex-biased signaling is proposed to result in distinct cellular responses to stress that are translated to different physiologic and behavioral coping mechanisms and that can have different pathologic consequences. Because stress has been implicated in diverse medical and psychiatric diseases, these sex differences in CRF1 signaling could explain sex differences in a multitude of disorders. The possibility that analogous sex differences may occur with other G-protein-coupled receptors underscores the impact of this effect and is discussed.
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Affiliation(s)
- Rita J Valentino
- The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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21
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Grammatopoulos DK. Insights into mechanisms of corticotropin-releasing hormone receptor signal transduction. Br J Pharmacol 2012; 166:85-97. [PMID: 21883143 DOI: 10.1111/j.1476-5381.2011.01631.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
During evolution, mammals have developed remarkably similar molecular mechanisms to respond to external challenges and maintain survival. Critical regulators of these mechanisms are the family of 'stress'-peptides that consists of the corticotropin-releasing hormone (CRH) and urocortins (Ucns). These neuropeptides 'fine-tune' integration of an intricate series of physiological responses involving the autonomic, endocrine, immune, cardiovascular and reproductive systems, which induce a spectrum of behavioural and homeostatic changes. CRH and Ucns exert their actions by activating two types of CRH receptors (CRH-R), CRH-R1 and CRH-R2, which belong to the class-B1 family of GPCRs. The CRH-Rs exhibit signalling promiscuity facilitated by their ability to couple to multiple G-proteins and regulate diverse intracellular networks that involve intracellular effectors such as cAMP and an array of PKs in an agonist and tissue-specific manner, a property that allows them to exert unique roles in the integration of homeostatic mechanisms. We only now begin to unravel the plethora of CRH-R biological actions and the transcriptional and post-translational mechanisms such as alternative mRNA splicing or phosphorylation-mediated desensitization developed to tightly control CRH-Rs biological activity and regulate their physiological actions. This review summarizes the current understanding of CRH-R signalling complexity and regulatory mechanisms that underpin cellular responses to CRH and Ucns.
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22
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Vilardaga JP, Gardella TJ, Wehbi VL, Feinstein TN. Non-canonical signaling of the PTH receptor. Trends Pharmacol Sci 2012; 33:423-31. [PMID: 22709554 DOI: 10.1016/j.tips.2012.05.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/11/2012] [Accepted: 05/15/2012] [Indexed: 12/31/2022]
Abstract
The classical model of arrestin-mediated desensitization of cell-surface G-protein-coupled receptors (GPCRs) is thought to be universal. However, this paradigm is incompatible with recent reports that the parathyroid hormone (PTH) receptor (PTHR), a crucial GPCR for bone and mineral ion metabolism, sustains G(S) activity and continues to generate cAMP for prolonged periods after ligand washout; during these periods the receptor is observed mainly in endosomes, associated with the bound ligand, G(S) and β-arrestins. In this review we discuss possible molecular mechanisms underlying sustained signaling by the PTHR, including modes of signal generation and attenuation within endosomes, as well as the biological relevance of such non-canonical signaling.
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Affiliation(s)
- Jean-Pierre Vilardaga
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15261, USA.
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23
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Fleck BA, Hoare SRJ, Pick RR, Bradbury MJ, Grigoriadis DE. Binding kinetics redefine the antagonist pharmacology of the corticotropin-releasing factor type 1 receptor. J Pharmacol Exp Ther 2012; 341:518-31. [PMID: 22357972 DOI: 10.1124/jpet.111.188714] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Corticotropin-releasing factor (CRF) receptor antagonists are under preclinical and clinical investigation for stress-related disorders. In this study the impact of receptor-ligand binding kinetics on CRF₁ receptor antagonist pharmacology was investigated by measuring the association rate constant (k₁), dissociation rate constant (k₋₁), and kinetically derived affinity at 37°C. Three aspects of antagonist pharmacology were reevaluated: comparative binding activity of advanced compounds, in vivo efficacy, and structure-activity relationships. Twelve lead compounds, with little previously noted difference of affinity, varied substantially in their kinetic binding activity with a 510-fold range of kinetically derived affinity (k₋₁/k₁), 170-fold range of k₋₁, and 13-fold range of k₁. The k₋₁ values indicated previous affinity measurements were not close to equilibrium, resulting in compression of the measured affinity range. Dissociation was exceptionally slow for three ligands (k₋₁ t(1/2) of 1.6-7.2 h at 37°C). Differences of binding behavior were consistent with in vivo pharmacodynamics (suppression of adrenocorticotropin in adrenalectomized rats). Ligand concentration-effect relationships correlated with their kinetically derived affinity. Two ligands that dissociated slowly (53 and 130 min) produced prolonged suppression, whereas only transient suppression was observed with a more rapidly dissociating ligand (16 min). Investigating the structure-activity relationship indicated exceptionally low values of k₁, approaching 100,000-fold less than the diffusion-limited rate. Retrospective interpretation of medicinal chemistry indicates optimizing specific elements of chemical structure overcame kinetic barriers in the association pathway, for example, constraint of the pendant aromatic orthogonal to the ligand core. Collectively, these findings demonstrate receptor binding kinetics provide new dimensions for understanding and potentially advancing the pharmacology of CRF₁ receptor antagonists.
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Affiliation(s)
- Beth A Fleck
- Neurocrine Biosciences Inc., San Diego, California, USA
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Murat B, Devost D, Andrés M, Mion J, Boulay V, Corbani M, Zingg HH, Guillon G. V1b and CRHR1 receptor heterodimerization mediates synergistic biological actions of vasopressin and CRH. Mol Endocrinol 2012; 26:502-20. [PMID: 22301784 DOI: 10.1210/me.2011-1202] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Vasopressin (AVP) and CRH synergistically regulate adrenocorticotropin and insulin release at the level of the pituitary and pancreas, respectively. Here, we first extended these AVP and CRH coregulation processes to the adrenal medulla. We demonstrate that costimulation of chromaffin cells by AVP and CRH simultaneously induces a catecholamine secretion exceeding the one induced by each hormone alone, thus demonstrating a net potentiation. To further elucidate the molecular mechanisms underlying this synergism, we coexpressed human V1b and CRH receptor (CRHR)1 receptor in HEK293 cells. In this heterologous system, AVP also potentiated CRH-stimulated cAMP accumulation in a dose-dependent and saturable manner. This effect was only partially mimicked by phorbol ester or inhibited by a phospholipase C inhibitor respectively. This finding suggests the existence of an new molecular mechanism, independent from second messenger cross talk. Similarly, CRH potentiated the AVP-induced inositol phosphates production. Using bioluminescence resonance energy transfer, coimmunoprecipitation, and receptor rescue experiments, we demonstrate that V1b and CRHR1 receptors assemble as heterodimers. Moreover, new pharmacological properties emerged upon receptors cotransfection. Taken together, these data strongly suggest that direct molecular interactions between V1b and CRHR1 receptors play an important role in mediating the synergistic interactions between these two receptors.
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Affiliation(s)
- Brigitte Murat
- Institut de Génomique Fonctionnelle, 141 Rue de la Cardonille, Montpellier Cedex 05, France
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Punn A, Chen J, Delidaki M, Tang J, Liapakis G, Lehnert H, Levine MA, Grammatopoulos DK. Mapping structural determinants within third intracellular loop that direct signaling specificity of type 1 corticotropin-releasing hormone receptor. J Biol Chem 2012; 287:8974-85. [PMID: 22247544 PMCID: PMC3308756 DOI: 10.1074/jbc.m111.272161] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The type 1 corticotropin-releasing hormone receptor (CRH-R1) influences biological responses important for adaptation to stressful stimuli, through activation of multiple downstream effectors. The structural motifs within CRH-R1 that mediate G protein activation and signaling selectivity are unknown. The aim of this study was to gain insights about important structural determinants within the third intracellular loop (IC3) of the human CRH-R1α important for cAMP and ERK1/2 pathways activation and selectivity. We investigated the role of the juxtamembrane regions of IC3 by mutating amino acid cassettes or specific residues to alanine. Although simultaneous tandem alanine mutations of both juxtamembrane regions Arg292-Met295 and Lys311-Lys314 reduced ligand binding and impaired signaling, all other mutant receptors retained high affinity binding, indistinguishable from wild-type receptor. Agonist-activated receptors with tandem mutations at the proximal or distal terminal segments enhanced activation of adenylyl cyclase by 50–75% and diminished activation of inositol trisphosphate and ERK1/2 by 60–80%. Single Ala mutations identified Arg292, Lys297, Arg310, Lys311, and Lys314 as important residues for the enhanced activation of adenylyl cyclase, partly due to reduced inhibition of adenylyl cyclase activity by pertussis toxin-sensitive G proteins. In contrast, mutation of Arg299 reduced receptor signaling activity and cAMP response. Basic as well as aliphatic amino acids within both juxtamembrane regions were identified as important for ERK1/2 phosphorylation through activation of pertussis toxin-sensitive G proteins as well as Gq proteins. These data uncovered unexpected roles for key amino acids within the highly conserved hydrophobic N- and C-terminal microdomains of IC3 in the coordination of CRH-R1 signaling activity.
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Affiliation(s)
- Anu Punn
- Department of Endocrinology and Metabolism, Clinical Sciences Research Institute, Warwick Medical School, University of Warwick, Coventry, United Kingdom
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Chronic stress exacerbates tau pathology, neurodegeneration, and cognitive performance through a corticotropin-releasing factor receptor-dependent mechanism in a transgenic mouse model of tauopathy. J Neurosci 2011; 31:14436-49. [PMID: 21976528 DOI: 10.1523/jneurosci.3836-11.2011] [Citation(s) in RCA: 188] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Because overactivation of the hypothalamic-pituitary-adrenal (HPA) axis occurs in Alzheimer's disease (AD), dysregulation of stress neuromediators may play a mechanistic role in the pathophysiology of AD. However, the effects of stress on tau phosphorylation are poorly understood, and the relationship between corticosterone and corticotropin-releasing factor (CRF) on both β-amyloid (Aβ) and tau pathology remain unclear. Therefore, we first established a model of chronic stress, which exacerbates Aβ accumulation in Tg2576 mice and then extended this stress paradigm to a tau transgenic mouse model with the P301S mutation (PS19) that displays tau hyperphosphorylation, insoluble tau inclusions and neurodegeneration. We show for the first time that both Tg2576 and PS19 mice demonstrate a heightened HPA stress profile in the unstressed state. In Tg2576 mice, 1 month of restraint/isolation (RI) stress increased Aβ levels, suppressed microglial activation, and worsened spatial and fear memory compared with nonstressed mice. In PS19 mice, RI stress promoted tau hyperphosphorylation, insoluble tau aggregation, neurodegeneration, and fear-memory impairments. These effects were not mimicked by chronic corticosterone administration but were prevented by pre-stress administration of a CRF receptor type 1 (CRF(1)) antagonist. The role for a CRF(1)-dependent mechanism was further supported by the finding that mice overexpressing CRF had increased hyperphosphorylated tau compared with wild-type littermates. Together, these results implicate HPA dysregulation in AD neuropathogenesis and suggest that prolonged stress may increase Aβ and tau hyperphosphorylation. These studies also implicate CRF in AD pathophysiology and suggest that pharmacological manipulation of this neuropeptide may be a potential therapeutic strategy for AD.
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Jagoda EM, Lang L, McCullough K, Contoreggi C, Kim BM, Ma Y, Rice KC, Szajek LP, Eckelman WC, Kiesewetter DO. [(76) Br]BMK-152, a nonpeptide analogue, with high affinity and low nonspecific binding for the corticotropin-releasing factor type 1 receptor. Synapse 2011; 65:910-8. [PMID: 21308801 PMCID: PMC3625961 DOI: 10.1002/syn.20919] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 01/20/2011] [Indexed: 11/07/2022]
Abstract
Corticotropin-releasing factor (CRF), a neuropeptide, regulates endocrine and autonomic responses to stress through G-protein coupled receptors, CRF(1) or CRF(2) . A PET ligand able to monitor changes in CRF(1) receptor occupancy in vivo would aid in understanding the pathophysiology of stress-related diseases as well as in the clinical development of nonpeptide antagonists with therapeutic value. We have radiolabeled the CRF(1) receptor ligand, [8-(4-bromo-2,6-dimethoxyphenyl)-2,7-dimethylpyrazolo[1,5-α][1,3,5]triazin-4-yl]-N,N-bis-(2-methoxyethyl)amine (BMK-152) (ClogP = 2.6), at both the 3 and 4 position with [(76) Br]. Using in vitro autoradiography saturation studies the 4-[(76) Br]BMK-152 exhibited high affinity binding to both rat (K(d) = 0.23 ± 0.07 nM; n = 3) and monkey frontal cortex (K(d) = 0.31 ± 0.08 nM; n = 3) consistent with CRF(1) receptor regional distribution whereas with the 3-[(76) Br]BMK-152, the K(d) s could not be determined due to high nonspecific binding. In vitro autoradiography competition studies using [(125) I]Tyr(0) -o-CRF confirmed that 3-Br-BMK-152 (K(i) = 24.4 ± 4.9 nM; n = 3) had lower affinity (70-fold) than 4-Br-BMK-152 (K(i) = 0.35 ± 0.07 nM; n = 3) in monkey frontal cortex and similiar studies using [(125) I]Sauvagine confirmed CRF(1) receptor selectivity. In vivo studies with P-glycoprotein (PGP) knockout mice (KO) and their wild-type littermates (WT) showed that the brain uptake of 3-[(76) Br]BMK/4-[(76) Br]BMK was increased less than twofold in KO versus WT indicating that 3-[(76) Br]BMK-152/4-[(76) Br]BMK was not a Pgp substrate. Rat brain uptakes of 4-[(76) Br] BMK-152 from ex vivo autoradiography studies showed regional localization consistent with known published CRF(1) receptor distribution and potential as a PET ligand for in vivo imaging of CRF(1) receptors.
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Affiliation(s)
- Elaine M Jagoda
- PET Radiochemistry Group, NIBIB, National Institutes of Health, Bethesda, Maryland 20892-1088, USA.
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Paez-Pereda M, Hausch F, Holsboer F. Corticotropin releasing factor receptor antagonists for major depressive disorder. Expert Opin Investig Drugs 2011; 20:519-35. [PMID: 21395482 DOI: 10.1517/13543784.2011.565330] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Major depressive disorder is a serious and common psychiatric illness, and many of the depressive patients benefit from pharmacological treatment. Available antidepressants produce remission in only about 30 -- 40% of the patients. Therefore, new concepts are being explored for the development of innovative antidepressants with higher efficacy. AREAS COVERED The use of corticotropin releasing factor type 1 (CRF1) receptor antagonists for depression is supported by abundant evidence of target validation, the availability of in vitro and in vivo assays and specific small ligands. Some of these compounds have advanced to clinical studies, with discouraging results so far in depression. This review covers the development of CRF1 receptor antagonists at different stages of the development pipeline of the pharmaceutical industry and its bottlenecks. Most of the available CRF1 receptor antagonists known so far share a common chemical scaffold. We present possible strategies to overcome obstacles in the discovery and development process at the levels of library screenings and clinical studies to find more diverse compounds. EXPERT OPINION CRF1 receptor antagonists are expected to be beneficial only for those patients with CRF overexpression and the need for tests to identify these individuals is discussed. New technical developments and diagnostic tools might eventually lead to a more successful treatment of major depression with CRF1 receptor antagonists.
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Vilardaga JP, Romero G, Friedman PA, Gardella TJ. Molecular basis of parathyroid hormone receptor signaling and trafficking: a family B GPCR paradigm. Cell Mol Life Sci 2011; 68:1-13. [PMID: 20703892 PMCID: PMC3568769 DOI: 10.1007/s00018-010-0465-9] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 07/06/2010] [Accepted: 07/09/2010] [Indexed: 12/14/2022]
Abstract
The parathyroid hormone (PTH) receptor type 1 (PTHR), a G protein-coupled receptor (GPCR), transmits signals to two hormone systems-PTH, endocrine and homeostatic, and PTH-related peptide (PTHrP), paracrine-to regulate different biological processes. PTHR responds to these hormonal stimuli by activating heterotrimeric G proteins, such as G(S) that stimulates cAMP production. It was thought that the PTHR, as for all other GPCRs, is only active and signals through G proteins on the cell membrane, and internalizes into a cell to be desensitized and eventually degraded or recycled. Recent studies with cultured cell and animal models reveal a new pathway that involves sustained cAMP signaling from intracellular domains. Not only do these studies challenge the paradigm that cAMP production triggered by activated GPCRs originates exclusively at the cell membrane but they also advance a comprehensive model to account for the functional differences between PTH and PTHrP acting through the same receptor.
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Affiliation(s)
- Jean-Pierre Vilardaga
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA.
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Gordon JC, Edwards P, Elmore CS, Lazor LA, Paschetto K, Bostwick R, Sylvester M, Mauger R, Scott C, Aharony D. [¹²⁵I]YP20: a novel radioligand specific for the extracellular domain of the CRF₁ receptor. Eur J Pharmacol 2010; 649:59-63. [PMID: 20854803 DOI: 10.1016/j.ejphar.2010.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 08/12/2010] [Accepted: 09/06/2010] [Indexed: 11/25/2022]
Abstract
The peptide corticotropin-releasing factor (CRF) binds to the CRF₁ receptor via a two-domain mechanism such that the extracellular domain (ECD) of the receptor captures the CRF's C-terminus to facilitate the binding of CRF's N-terminus to the juxta-membrane or "J"-site. Known small molecule antagonists bind to the J-site while known CRF₁ receptor peptide radioligands bind to both sites. We report here the in vitro binding properties of the first radioligand that binds exclusively to the ECD of the CRF₁ receptor. This ligand, which we named [¹²⁵I]Yamada peptide 20 ([¹²⁵I]YP20), is a radiolabeled analog of a synthetic peptide first reported by Yamada et al. (2004). We confirmed its high affinity for the [¹²⁵I]CRF binding site on the hCRF₁ receptor and also found it to potently antagonize CRF-stimulated cAMP production in hCRF₁-CHO cells. Under optimized conditions, 20 pM [¹²⁵I]YP20 reproducibly bound to hCRF₁-CHO membranes with a pharmacology consistent with binding specific to the ECD of the CRF₁ receptor. Saturation binding studies revealed the presence of a high affinity site with an estimated K(d) of ≈0.9 nM. The kinetic association of 20 pM [¹²⁵I]YP20 binding best fit to a rapid component (t(1/2)=0.69 min) and a sluggish component (t(1/2)=42 min). [¹²⁵I]YP20's specific binding was rapidly reversible with dissociation kinetics also best described by two phases (t(1/2)=0.92 min and t(1/2)=11.7 min). While [¹²⁵I]YP20's binding kinetics are complex, its high affinity and pharmacological specificity indicate that it is an excellent radioligand for probing the ECD site of the CRF₁ receptor.
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Affiliation(s)
- John C Gordon
- CNS Discovery, AstraZeneca, Wilmington, Delaware 19850-5437, USA.
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Hoare SRJ. Allosteric modulators of class B G-protein-coupled receptors. Curr Neuropharmacol 2010; 5:168-79. [PMID: 19305799 PMCID: PMC2656815 DOI: 10.2174/157015907781695928] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Accepted: 04/05/2007] [Indexed: 11/22/2022] Open
Abstract
Class B GPCR’s are activated by peptide ligands, typically 30-40 amino acid residues, that are involved in major physiological functions such as glucose homeostasis (glucagon and glucagon-like peptide 1), calcium homeostasis and bone turnover (parathyroid hormone and calcitonin), and control of the stress axis (corticotropin-releasing factor). Peptide therapeutics have been developed targeting these receptors but development of nonpeptide ligands, enabling oral administration, has proved challenging. Allosteric modulation of these receptors provides a potential route to developing nonpeptide ligands that inhibit, activate, or potentiate activation of these receptors. Here the known mechanisms of allosteric modulators targeting Class B GPCR’s are reviewed, particularly nonpeptide antagonists of the corticotropin-releasing factor 1 receptor and allosteric enhancers of the glucagon-like peptide-1 receptor. Also discussed is the potential for antagonist ligands to operate by competitive inhibition of one of the peptide binding sites, analogous to the Charniere mechanism. These mechanisms are then used to discuss potential strategies and management of pharmacological complexity in the future development of allosteric modulators for Class B GPCR’s.
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Affiliation(s)
- Sam R J Hoare
- Department of Discovery Biology, Neurocrine Biosciences Inc., San Diego, CA 92130, USA.
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Allosteric antagonist binding sites in class B GPCRs: corticotropin receptor 1. J Comput Aided Mol Des 2010; 24:659-74. [PMID: 20512399 DOI: 10.1007/s10822-010-9364-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 05/03/2010] [Indexed: 10/19/2022]
Abstract
The 41 amino acid neuropeptide, corticotropin-releasing factor (CRF) and its associated receptors CRF(1)-R and CRF(2)-R have been targeted for treating stress related disorders. Both CRF(1)-R and CRF(2)-R belong to the class B G-protein coupled receptors for which little information is known regarding the small molecule antagonist binding characteristics. However, it has been shown recently that different non-peptide allosteric ligands stabilize different receptor conformations for CRF(1)-R and hence an understanding of the ligand induced receptor conformational changes is important in the pharmacology of ligand binding. In this study, we modeled the receptor and identified the binding sites of representative small molecule allosteric antagonists for CRF(1)-R. The predicted binding sites of the investigated compounds are located within the transmembrane (TM) domain encompassing TM helices 3, 5 and 6. The docked compounds show strong interactions with H228 on TM3 and M305 on TM5 that have also been implicated in the binding by site directed mutation studies. H228 forms a hydrogen bond of varied strengths with all the antagonists in this study and this is in agreement with the decreased binding affinity of several compounds with H228F mutation. Also mutating M305 to Ile showed a sharp decrease in the calculated binding energy whereas the binding energy loss on M305 to Leu was less significant. These results are in qualitative agreement with the decrease in binding affinities observed experimentally. We further predicted the conformational changes in CRF(1)-R induced by the allosteric antagonist NBI-27914. Movement of TM helices 3 and 5 are dominant and generates three degenerate conformational states two of which are separated by an energy barrier from the third, when bound to NBI-27914. Binding of NBI-27914 was predicted to improve the interaction of the ligand with M305 and also enhanced the aromatic stacking between the ligand and F232 on TM3. A virtual ligand screening of ~13,000 compounds seeded with ~350 CRF(1)-R specific active antagonists performed on the NBI-27914 stabilized conformation of CRF(1)-R yielded a 44% increase in enrichment compared to the initially modeled receptor conformation at a 10% cutoff. The NBI-27914 stabilized conformation also shows a high enrichment for high affinity antagonists compared to the weaker ones. Thus, the conformational changes induced by NBI-27914 improved the ligand screening efficiency of the CRF(1)-R model and demonstrate a generalized application of the method in drug discovery.
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Progress in corticotropin-releasing factor-1 antagonist development. Drug Discov Today 2010; 15:371-83. [PMID: 20206287 DOI: 10.1016/j.drudis.2010.02.011] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2009] [Revised: 12/16/2009] [Accepted: 02/24/2010] [Indexed: 01/02/2023]
Abstract
Corticotropin releasing factor (CRF) receptor antagonists have been sought since the stress-secreted peptide was isolated in 1981. Although evidence is mixed concerning the efficacy of CRF(1) antagonists as antidepressants, CRF(1) antagonists might be novel pharmacotherapies for anxiety and addiction. Progress in understanding the two-domain model of ligand-receptor interactions for CRF family receptors might yield chemically novel CRF(1) receptor antagonists, including peptide CRF(1) antagonists, antagonists with signal transduction selectivity and nonpeptide CRF(1) antagonists that act via the extracellular (rather than transmembrane) domains. Novel ligands that conform to the prevalent pharmacophore and exhibit drug-like pharmacokinetic properties have been identified. The therapeutic utility of CRF(1) antagonists should soon be clearer: several small molecules are currently in Phase II/III clinical trials for depression, anxiety and irritable bowel syndrome.
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Parker MS, Sah R, Balasubramaniam A, Sallee FR, Sweatman T, Park EA, Parker SL. Dimers of the neuropeptide Y (NPY) Y2 receptor show asymmetry in agonist affinity and association with G proteins. J Recept Signal Transduct Res 2009; 28:437-51. [PMID: 18946765 DOI: 10.1080/10799890802447423] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In conditions precluding activation of G proteins, the binding of agonists to dimers of the neuropeptide Y (NPY) Y2 receptor shows two components of similar size, but differing in affinity. The dimers of all NPY receptors are solubilized as approximately 180-kDa complexes containing one G protein alpha beta gamma trimer. These heteropentamers are stable to excess agonists, chelators, and alkylators. However, dispersion in the weak surfactant cholate releases approximately 300-kDa complexes. These findings indicate that both protomers in the Y2 dimer are associated with G protein heterotrimers, but the extent of interaction depends on affinity for the agonist peptide. The G protein in contact with the first-liganded, higher-affinity protomer should have a stronger interaction with the receptor and a larger probability of activation.
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Affiliation(s)
- M S Parker
- Department of Molecular Cell Sciences, University of Memphis, Memphis, Tennessee, USA.
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Parthier C, Reedtz-Runge S, Rudolph R, Stubbs MT. Passing the baton in class B GPCRs: peptide hormone activation via helix induction? Trends Biochem Sci 2009; 34:303-10. [PMID: 19446460 DOI: 10.1016/j.tibs.2009.02.004] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 02/05/2009] [Accepted: 02/09/2009] [Indexed: 12/25/2022]
Abstract
G-protein-coupled receptors (GPCRs) represent the largest constellation of validated drug targets. Crystal structures of class A GPCRs have facilitated major advances in understanding the principles underlying GPCR activation. By contrast, relatively little is known about class B GPCRs, a family of receptors for a variety of therapeutically relevant peptide hormones. Encouraging progress has recently been made through the structural elucidation of several extracellular hormone-binding domains of class B GPCRs in complex with their natural ligands or synthetic analogues. The structures reveal similar modes of ligand binding, with concomitant alpha-helical structuring of the ligand. The latter suggests an attractive mechanical model for class B GPCR activation.
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Affiliation(s)
- Christoph Parthier
- Institut für Biochemie und Biotechnologie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany.
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Warnock G, Moechars D, Langlois X, Steckler T. In vivo evidence for ligand-specific receptor activation in the central CRF system, as measured by local cerebral glucose utilization. Peptides 2009; 30:947-54. [PMID: 19428773 DOI: 10.1016/j.peptides.2009.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Revised: 01/08/2009] [Accepted: 01/09/2009] [Indexed: 10/21/2022]
Abstract
Corticotropin-releasing factor (CRF) is well known for its role in the hypothalamic-pituitary-adrenocortical (HPA) axis and its involvement in stress and anxiety. CRF acts via two main receptor subtypes, CRF(1) and CRF(2). Other endogenous CRF-related peptide ligands are the Urocortins 1 and 2 and Stresscopin. While CRF is thought to mediate its anxiogenic-like properties through CRF(1), the role of CRF(2) and its endogenous ligands Urocortin 2 and Stresscopin are less clear, with a suggested role in mediating the delayed effects of stress. Measurement of local cerebral glucose utilization (LCGU) provides an estimate of neuronal activity, and is of potential use as a translational tool in comparison to FDG PET. We hypothesized that comparison of the patterns of metabolic changes induced by CRF-related peptides could provide further information on their role in the brain. The present studies examined the effects of CRF-related peptides on LCGU, and the role of CRF(1) and CRF(2) in the CRF-induced LCGU response. CRF induced increases in LCGU in hypothalamic, thalamic, cerebellar and hippocampal regions, and further studies using antagonists or mutant mice lacking a functional CRF(1) receptor clearly suggested a role for CRF(2) in this effect. Urocortin 1 increased LCGU in a dissected hindbrain region. However, central administration of the CRF(2)-selective agonists Urocortin 2 and Stresscopin failed to affect LCGU, which may suggest ligand-dependent receptor activation within the CRF system. The present data supports a role for CRF(2) in the regulation of neuronal glucose metabolism.
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Affiliation(s)
- Geoff Warnock
- Dept. Psychiatry, RED Europe, Johnson & Johnson PRD, Beerse, Belgium.
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Drugability of extracellular targets: discovery of small molecule drugs targeting allosteric, functional, and subunit-selective sites on GPCRs and ion channels. Neuropsychopharmacology 2009; 34:106-25. [PMID: 18800070 DOI: 10.1038/npp.2008.149] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Beginning with the discovery of the structure of deoxyribose nucleic acid in 1953, by James Watson and Francis Crick, the sequencing of the entire human genome some 50 years later, has begun to quantify the classes and types of proteins that may have relevance to human disease with the promise of rapidly identifying compounds that can modulate these proteins so as to have a beneficial and therapeutic outcome. This so called 'drugable space' involves a variety of membrane-bound proteins including the superfamily of G-protein-coupled receptors (GPCRs), ion channels, and transporters among others. The recent number of novel therapeutics targeting membrane-bound extracellular proteins that have reached the market in the past 20 years however pales in magnitude when compared, during the same timeframe, to the advancements made in the technologies available to aid in the discovery of these novel therapeutics. This review will consider select examples of extracellular drugable targets and focus on the GPCRs and ion channels highlighting the corticotropin releasing factor (CRF) type 1 and gamma-aminobutyric acid receptors, and the Ca(V)2.2 voltage-gated ion channel. These examples will elaborate current technological advancements in drug discovery and provide a prospective framework for future drug development.
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Pioszak AA, Parker NR, Suino-Powell K, Xu HE. Molecular recognition of corticotropin-releasing factor by its G-protein-coupled receptor CRFR1. J Biol Chem 2008; 283:32900-12. [PMID: 18801728 PMCID: PMC2583312 DOI: 10.1074/jbc.m805749200] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Revised: 09/17/2008] [Indexed: 11/06/2022] Open
Abstract
The bimolecular interaction between corticotropin-releasing factor (CRF), a neuropeptide, and its type 1 receptor (CRFR1), a class B G-protein-coupled receptor (GPCR), is crucial for activation of the hypothalamic-pituitary-adrenal axis in response to stress, and has been a target of intense drug design for the treatment of anxiety, depression, and related disorders. As a class B GPCR, CRFR1 contains an N-terminal extracellular domain (ECD) that provides the primary ligand binding determinants. Here we present three crystal structures of the human CRFR1 ECD, one in a ligand-free form and two in distinct CRF-bound states. The CRFR1 ECD adopts the alpha-beta-betaalpha fold observed for other class B GPCR ECDs, but the N-terminal alpha-helix is significantly shorter and does not contact CRF. CRF adopts a continuous alpha-helix that docks in a hydrophobic surface of the ECD that is distinct from the peptide-binding site of other class B GPCRs, thereby providing a basis for the specificity of ligand recognition between CRFR1 and other class B GPCRs. The binding of CRF is accompanied by clamp-like conformational changes of two loops of the receptor that anchor the CRF C terminus, including the C-terminal amide group. These structural studies provide a molecular framework for understanding peptide binding and specificity by the CRF receptors as well as a template for designing potent and selective CRFR1 antagonists for therapeutic applications.
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Affiliation(s)
- Augen A Pioszak
- Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, Michigan 49503, USA.
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40
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Assil-Kishawi I, Samra TA, Mierke DF, Abou-Samra AB. Residue 17 of sauvagine cross-links to the first transmembrane domain of corticotropin-releasing factor receptor 1 (CRFR1). J Biol Chem 2008; 283:35644-51. [PMID: 18955489 DOI: 10.1074/jbc.m806351200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Corticotropin-releasing factor receptor 1 (CRFR1) mediates the physiological actions of corticotropin-releasing factor in the anterior pituitary gland and the central nervous system. Using chemical cross-linking we have previously reported that residue 16 of sauvagine (SVG) is in a close proximity to the second extracellular loop of CRFR1. Here we introduced p-benzoylphenylalanine (Bpa) at position 17 of a sauvagine analog, [Tyr0, Gln1, Bpa17]SVG, to covalently label CRFR1 and characterize the cross-linking site. Using a combination of receptor mutagenesis, peptide mapping, and N-terminal sequencing, we identified His117 within the first transmembrane domain (TM1) of CRFR1 as the cross-linking site for Bpa17 of 125I-[Tyr0, Gln1, Bpa17]SVG. These data indicate that, within the SVG-CRFR1 complex, residue 17 of the ligand lies within a 9 angstroms distance from residue 117 of the TM1 of CRFR1. The molecular proximity between residue 17 of the ligand and TM1 of CRFR1 described here and between residue 16 of the ligand and the CRFR1 second extracellular loop described previously provides useful molecular constraints for modeling ligand-receptor interaction in mammalian cells expressing CRFR1.
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Affiliation(s)
- Iman Assil-Kishawi
- Endocrine Division, Department of Internal Medicine, Wayne State University School of Medicine, University Health Center, Detroit, Mighigan 48201, USA
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41
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Richardson HN, Zhao Y, Fekete ÉM, Funk CK, Wirsching P, Janda K, Zorrilla EP, Koob GF. MPZP: a novel small molecule corticotropin-releasing factor type 1 receptor (CRF1) antagonist. Pharmacol Biochem Behav 2008; 88:497-510. [PMID: 18031798 PMCID: PMC3319109 DOI: 10.1016/j.pbb.2007.10.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2007] [Revised: 10/13/2007] [Accepted: 10/17/2007] [Indexed: 10/22/2022]
Abstract
The extrahypothalamic stress peptide corticotropin-releasing factor (CRF) system is an important regulator of behavioral responses to stress. Dysregulation of CRF and the CRF type 1 receptor (CRF(1)) system is hypothesized to underlie many stress-related disorders. Modulation of the CRF(1) system by non-peptide antagonists currently is being explored as a therapeutic approach for anxiety disorders and alcohol dependence. Here, we describe a new, less hydrophilic (cLogP approximately 2.95), small molecule, non-peptide CRF(1) antagonist with high affinity (K(i)=4.9 nM) and specificity for CRF(1) receptors: N,N-bis(2-methoxyethyl)-3-(4-methoxy-2-methylphenyl)-2,5-dimethyl-pyrazolo[1,5-a] pyrimidin-7-amine (MPZP). The compound was systemically administered to adult male rats in two behavioral models dependent on the CRF(1) system: defensive burying (0, 5, 20 mg/kg, n=6-11 for each dose) and alcohol dependence (0, 5, 10, 20 mg/kg, n=8 for each self-administration group). Acute administration of MPZP reduced burying behavior in the defensive burying model of active anxiety-like behavior. MPZP also attenuated withdrawal-induced excessive drinking in the self-administration model of alcohol dependence without affecting nondependent alcohol drinking or water consumption. The present findings support the proposed significance of the CRF(1) system in anxiety and alcohol dependence and introduce a promising new compound for further development in the treatment of alcohol dependence and stress-related disorders.
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Affiliation(s)
- Heather N. Richardson
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, 92037 California, USA
| | - Yu Zhao
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, 92037 California, USA
| | - Éva M. Fekete
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, 92037 California, USA
- Institute of Physiology, Pécs University Medical School, 7602 Pécs, Hungary
| | - Cindy K. Funk
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, 92037 California, USA
- Institut National de la Sante et de la Recherche Medicale, France
| | - Peter Wirsching
- Department of Chemistry, The Scripps Research Institute, La Jolla, 92037 California, USA
| | - Kim Janda
- Department of Chemistry, The Scripps Research Institute, La Jolla, 92037 California, USA
| | - Eric P. Zorrilla
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, 92037 California, USA
- Harold L. Dorris Neurological Research Institute, The Scripps Research Institute, La Jolla, 92037 California, USA
| | - George F. Koob
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, 92037 California, USA
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42
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Hoare SRJ, Fleck BA, Gross RS, Crowe PD, Williams JP, Grigoriadis DE. Allosteric ligands for the corticotropin releasing factor type 1 receptor modulate conformational states involved in receptor activation. Mol Pharmacol 2008; 73:1371-80. [PMID: 18239030 DOI: 10.1124/mol.107.042978] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Allosteric modulators of G-protein-coupled receptors can regulate conformational states involved in receptor activation ( Mol Pharmacol 58: 1412-1423, 2000 ). This hypothesis was investigated for the corticotropin-releasing factor type 1 (CRF(1)) receptor using a novel series of ligands with varying allosteric effect on CRF binding (inhibition to enhancement). For the G-protein-uncoupled receptor, allosteric modulation of CRF binding was correlated with nonpeptide ligand signaling activity; inverse agonists inhibited and agonists enhanced CRF binding. These data were quantitatively consistent with a two-state equilibrium underlying the modulation of CRF binding to the G-protein-uncoupled receptor. We next investigated the allosteric effect on CRF-stimulated G-protein coupling. Ligands inhibited CRF-stimulated cAMP accumulation regardless of their effect on the G-protein-uncoupled state. The modulators reduced CRF E(max) values, suggesting that they reduced the efficacy of a CRF-bound active state to couple to G-protein. Consistent with this hypothesis, the modulators inhibited binding to a guanine nucleotide-sensitive state. Together, the results are quantitatively consistent with a model in which 1) the receptor exists in three predominant states: an inactive state, a weakly active state, and a CRF-bound fully active state; 2) allosteric inverse agonists stabilize the inactive state, and allosteric agonists stabilize the weakly active state; and 3) antagonism of CRF signaling results from destabilization of the fully active state. These findings imply that nonpeptide ligands differentially modulate conformational states involved in CRF(1) receptor activation and suggest that different conformational states can be targeted in designing nonpeptide ligands to inhibit CRF signaling.
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Affiliation(s)
- Sam R J Hoare
- Emerging Technologies Biomedical Research and Innovative Discovery Group, Neurocrine Biosciences Inc., 12790 El Camino Real, San Diego, CA 92130, USA.
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43
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Perrin MH, Grace CR, DiGruccio MR, Fischer WH, Maji SK, Cantle JP, Smith S, Manning G, Vale WW, Riek R. Distinct Structural and Functional Roles of Conserved Residues in the First Extracellular Domain of Receptors for Corticotropin-releasing Factor and Related G-protein-coupled Receptors. J Biol Chem 2007; 282:37529-36. [DOI: 10.1074/jbc.m703748200] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Teli T, Markovic D, Hewitt ME, Levine MA, Hillhouse EW, Grammatopoulos DK. Structural domains determining signalling characteristics of the CRH-receptor type 1 variant R1beta and response to PKC phosphorylation. Cell Signal 2007; 20:40-9. [PMID: 17913459 DOI: 10.1016/j.cellsig.2007.08.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Accepted: 08/06/2007] [Indexed: 10/22/2022]
Abstract
Mammalian adaptive mechanisms to stressful stimuli involve release of corticotropin-releasing hormone (CRH) and downstream activation of specific G-protein-coupled 7 transmembrane domain receptors. These CRH receptors (CRH-R) are expressed as multiple mRNA spliced variants. In contrast to other mammals, the human type 1 CRH-R gene contains an additional exon (exon 6) that needs to be spliced out in order to generate the fully active CRH-R1alpha. Transcription of all 14 exons results in a CRH-R1 variant (CRH-R1beta) with an extended 1st intracellular loop (IC1); this sequence modification impairs signalling activity and alters receptor responsiveness to PKC-induced phosphorylation that leads to signalling desensitization and receptor endocytosis. To elucidate structure-function relationships and delineate sequences involved in CRH-R1beta properties, site directed mutagenesis was used to introduce a number of specific mutations into IC1 of CRH-R1beta as well as replace specific phospho-acceptor residues within the aminoacid sequence of CRH-R1alpha and CRH-R1beta. Mutant receptors were transiently expressed in human embryonic kidney (HEK293) cells and tested for their abilities to increase intracellular cAMP and their response to PKC-induced phosphorylation. Results identified a penta-aminoacid cassette within the 29-aminoacid insert of CRH-R1beta, which contains multiple positive charged aminoacids (F170-R174), as an important structural determinant for the impaired cAMP response. Furthermore, serine at position 408 in the carboxy-terminus appears to be important for mediating CRH-R1alpha resistance, but not CRH-R1beta susceptibility, to PKC-induced desensitization and internalization. These findings provide new insights about the structural determinants of CRH-R1 coupling to Gs proteins and response to protein kinase phosphorylation.
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Affiliation(s)
- Thalia Teli
- Endocrinology and Metabolism, Division of Clinical Sciences, Warwick Medical School, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
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45
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Grigoriadis DE. The corticotropin-releasing factor receptor: a novel target for the treatment of depression and anxiety-related disorders. Expert Opin Ther Targets 2007; 9:651-84. [PMID: 16083336 DOI: 10.1517/14728222.9.4.651] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The treatment of mood disorders has been the subject of intense study for more than half a century and has resulted in the discovery and availability of a number of compounds that have seen tremendous success in the management of major depression and anxiety-related disorders. In spite of this success, these drugs have not provided a complete therapeutic solution for all patients and this has revitalised the need for a greater understanding of the underlying molecular mechanisms and targets involved in these disorders. Elucidation of these novel targets will enable the development of a better class of compounds which could benefit a greater majority of the patient population and be devoid of the current side effect liabilities. Towards that end, this review examines, in detail, the prospect of one such target, the corticotropin-releasing factor system, as having an enhanced therapeutic profile with the potential of a broader range of efficacy with reduced side effect liabilities.
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Affiliation(s)
- Dimitri E Grigoriadis
- Department of Pharmacology and Lead Discovery, Neurocrine Biosciences, Inc., 12790 El Camino Real, San Diego, CA 92130, USA.
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Mesleh MF, Shirley WA, Heise CE, Ling N, Maki RA, Laura RP. NMR structural characterization of a minimal peptide antagonist bound to the extracellular domain of the corticotropin-releasing factor1 receptor. J Biol Chem 2006; 282:6338-46. [PMID: 17192263 DOI: 10.1074/jbc.m609816200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Natural peptide agonists of corticotrophin-releasing factor (CRF) receptors bind to the receptor by a two-site mechanism as follows: the carboxyl end of the ligand binds the N-terminal extracellular domain (ECD) of the receptor and the amino portion of the ligand binds the extracellular face of the seven transmembrane region. Recently, peptide antagonists homologous to the 12 C-terminal residues of CRF have been derived, which bind the CRF(1) receptor through an interaction with the ECD. Here we characterized the binding of a minimal 12-residue peptide antagonist while bound to the isolated ECD of the CRF(1) receptor. We have expressed and purified soluble and properly folded ECD independent from the seven-transmembrane region as a thioredoxin fusion protein in Escherichia coli. A model of the peptide antagonist, cyclic corticotrophin-releasing factor residues 30-41 (cCRF(30-41)), was calculated while bound to the recombinant ECD using transferred nuclear Overhauser effect spectroscopy. Although the peptide is unstructured in solution, it adopts an alpha-helical conformation when bound to the ECD. Residues of cCRF(30-41) comprising the binding interface with the ECD were mapped using saturation transfer difference NMR. Two hydrophobic residues (Met(38) and Ile(41)) as well as two amide groups (Asn(34) and the C-terminal amide) on one face of the helix defined the binding epitope of the antagonist. This epitope may be used as a starting point for development of non-peptide antagonists targeting the ECD of this receptor.
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Affiliation(s)
- Michael F Mesleh
- Department of Medicinal Chemistry, Neurocrine Biosciences, Inc., San Diego, California 92130, USA
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47
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Berger H, Heinrich N, Wietfeld D, Bienert M, Beyermann M. Evidence that corticotropin-releasing factor receptor type 1 couples to Gs- and Gi-proteins through different conformations of its J-domain. Br J Pharmacol 2006; 149:942-7. [PMID: 17057757 PMCID: PMC2014684 DOI: 10.1038/sj.bjp.0706926] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND AND PURPOSE According to the two-domain model for the corticotropin-releasing factor receptor type 1 (CRF(1)), peptide antagonists bind to the N-terminal domain (N-domain), non-peptide antagonists to the transmembrane region (J-domain), whereas peptide agonists attach to both the N- and J-domain of the receptor to express activity. The aim of this study was to search for possible differences in the antagonism of the Gs- and Gi-protein coupling of CRF(1) by a peptide (alpha-helical CRF(9-41)) and non-peptide antagonist (antalarmin), to determine whether the conformational requirements of the activated CRF(1) states for Gs and Gi coupling are similar or different. EXPERIMENTAL APPROACH We studied the inhibitory effect of alpha-helical CRF(9-41) and antalarmin on the coupling of CRF(1) to Gs- and Gi-protein in human embryonic kidney cells, using the [(35)S]-GTPgammaS binding stimulation assay. KEY RESULTS The non-peptide antagonized the receptor coupling to Gs competitively but that to Gi noncompetitively, and its antagonistic potency was different for urocortin- and sauvagine-evoked G-protein activation. In contrast, the peptide antagonist exhibited uniformly competitive antagonism. CONCLUSIONS AND IMPLICATIONS The results allow us to extend the two-domain model of CRF(1) activation by assuming that CRF(1) agonists activate the receptor by binding to at least two ensembles of J-domain configurations which couple to Gs or Gi, that are in turn antagonized by a non-peptide antagonist competitively and allosterically, respectively. It is further concluded that the allosteric mechanism of non-peptide antagonism is not valid for the Gs-mediated physiological activities of CRF(1).
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MESH Headings
- Allosteric Regulation
- Amphibian Proteins
- Binding, Competitive
- Cell Line
- Corticotropin-Releasing Hormone/pharmacology
- Dose-Response Relationship, Drug
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- GTP-Binding Protein alpha Subunits, Gs/metabolism
- Guanosine 5'-O-(3-Thiotriphosphate)
- Hormone Antagonists/pharmacology
- Humans
- Models, Molecular
- Peptide Fragments/pharmacology
- Peptide Hormones
- Peptides/pharmacology
- Protein Conformation
- Protein Structure, Tertiary
- Pyrimidines/pharmacology
- Pyrroles/pharmacology
- Receptors, Corticotropin-Releasing Hormone/chemistry
- Receptors, Corticotropin-Releasing Hormone/drug effects
- Receptors, Corticotropin-Releasing Hormone/genetics
- Receptors, Corticotropin-Releasing Hormone/metabolism
- Signal Transduction/drug effects
- Transfection
- Urocortins
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Affiliation(s)
- H Berger
- Department of Peptide Chemistry/Biochemistry, Leibniz Institute of Molecular Pharmacology Berlin, Germany
| | - N Heinrich
- Department of Peptide Chemistry/Biochemistry, Leibniz Institute of Molecular Pharmacology Berlin, Germany
| | - D Wietfeld
- Department of Peptide Chemistry/Biochemistry, Leibniz Institute of Molecular Pharmacology Berlin, Germany
| | - M Bienert
- Department of Peptide Chemistry/Biochemistry, Leibniz Institute of Molecular Pharmacology Berlin, Germany
| | - M Beyermann
- Department of Peptide Chemistry/Biochemistry, Leibniz Institute of Molecular Pharmacology Berlin, Germany
- Author for correspondence:
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48
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Hauger RL, Risbrough V, Brauns O, Dautzenberg FM. Corticotropin releasing factor (CRF) receptor signaling in the central nervous system: new molecular targets. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2006; 5:453-79. [PMID: 16918397 PMCID: PMC1925123 DOI: 10.2174/187152706777950684] [Citation(s) in RCA: 246] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Corticotropin-releasing factor (CRF) and the related urocortin peptides mediate behavioral, cognitive, autonomic, neuroendocrine and immunologic responses to aversive stimuli by activating CRF(1) or CRF(2) receptors in the central nervous system and anterior pituitary. Markers of hyperactive central CRF systems, including CRF hypersecretion and abnormal hypothalamic-pituitary-adrenal axis functioning, have been identified in subpopulations of patients with anxiety, stress and depressive disorders. Because CRF receptors are rapidly desensitized in the presence of high agonist concentrations, CRF hypersecretion alone may be insufficient to account for the enhanced CRF neurotransmission observed in these patients. Concomitant dysregulation of mechanisms stringently controlling magnitude and duration of CRF receptor signaling also may contribute to this phenomenon. While it is well established that the CRF(1) receptor mediates many anxiety- and depression-like behaviors as well as HPA axis stress responses, CRF(2) receptor functions are not well understood at present. One hypothesis holds that CRF(1) receptor activation initiates fear and anxiety-like responses, while CRF(2) receptor activation re-establishes homeostasis by counteracting the aversive effects of CRF(1) receptor signaling. An alternative hypothesis posits that CRF(1) and CRF(2) receptors contribute to opposite defensive modes, with CRF(1) receptors mediating active defensive responses triggered by escapable stressors, and CRF(2) receptors mediating anxiety- and depression-like responses induced by inescapable, uncontrollable stressors. CRF(1) receptor antagonists are being developed as novel treatments for affective and stress disorders. If it is confirmed that the CRF(2) receptor contributes importantly to anxiety and depression, the development of small molecule CRF(2) receptor antagonists would be therapeutically useful.
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Affiliation(s)
- Richard L Hauger
- San Diego VA Healthcare System, University of California San Diego, La Jolla, 929093-0603, USA.
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49
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Hoare SRJ, Brown BT, Santos MA, Malany S, Betz SF, Grigoriadis DE. Single amino acid residue determinants of non-peptide antagonist binding to the corticotropin-releasing factor1 (CRF1) receptor. Biochem Pharmacol 2006; 72:244-55. [PMID: 16750175 DOI: 10.1016/j.bcp.2006.04.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Accepted: 04/11/2006] [Indexed: 10/24/2022]
Abstract
The molecular interactions between non-peptide antagonists and the corticotropin-releasing factor type 1 (CRF1) receptor are poorly understood. A CRF1 receptor mutation has been identified that reduces binding affinity of the non-peptide antagonist NBI 27914 (M276I in transmembrane domain 5). We have investigated the mechanism of the mutation's effect using a combination of peptide and non-peptide ligands and receptor mutations. The M276I mutation reduced binding affinity of standard non-peptide antagonists 5-75-fold while having no effect on peptide ligand binding. We hypothesized that the side chain of isoleucine, beta-branched and so rotationally constrained when within an alpha-helix, introduces a barrier to non-peptide antagonist binding. In agreement with this hypothesis, mutation of M276 to the rotationally constrained valine produced similar reductions of affinity as M276I mutation, whereas mutation to leucine (with an unbranched beta-carbon) minimally affected non-peptide antagonist affinity. Mutation to alanine did not appreciably affect non-peptide antagonist affinity, implying the methionine side chain does not contribute directly to binding. Three observations suggested M276I/V mutations interfere with binding of the heterocyclic core of the compounds: (1) all compounds affected by M276I/V mutations possess a planar heterocyclic core. (2) None of the M276 mutations affected binding of an acylic compound. (3) The mutations differentially affected affinity of two compounds that differ only by core methylation. These findings imply that non-peptide antagonists, and specifically the heterocyclic core of such molecules, bind in the vicinity of M276 of the CRF1 receptor. M276 mutations did not affect peptide ligand binding and this residue is distant from determinants of peptide binding (predominantly in the extracellular regions), providing molecular evidence for non-overlapping (allosteric) binding sites for peptide and non-peptide ligands within the CRF1 receptor.
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Affiliation(s)
- Sam R J Hoare
- Department of Discovery Biology, Neurocrine Biosciences Inc., 12790 El Camino Real, San Diego, CA 92130, USA.
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50
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Hillhouse EW, Grammatopoulos DK. The molecular mechanisms underlying the regulation of the biological activity of corticotropin-releasing hormone receptors: implications for physiology and pathophysiology. Endocr Rev 2006; 27:260-86. [PMID: 16484629 DOI: 10.1210/er.2005-0034] [Citation(s) in RCA: 266] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The CRH receptor (CRH-R) is a member of the secretin family of G protein-coupled receptors. Wide expression of CRH-Rs in the central nervous system and periphery ensures that their cognate agonists, the family of CRH-like peptides, are capable of exerting a wide spectrum of actions that underpin their critical role in integrating the stress response and coordinating the activity of fundamental physiological functions, such as the regulation of the cardiovascular system, energy balance, and homeostasis. Two types of mammal CRH-R exist, CRH-R1 and CRH-R2, each with unique splicing patterns and remarkably distinct pharmacological properties, but similar signaling properties, probably reflecting their distinct and sometimes contrasting biological functions. The regulation of CRH-R expression and activity is not fully elucidated, and we only now begin to fully understand the impact on mammalian pathophysiology. The focus of this review is the current and evolving understanding of the molecular mechanisms controlling CRH-R biological activity and functional flexibility. This shows notable tissue-specific characteristics, highlighted by their ability to couple to distinct G proteins and activate tissue-specific signaling cascades. The type of activating agonist, receptor, and target cell appears to play a major role in determining the overall signaling and biological responses in health and disease.
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Affiliation(s)
- Edward W Hillhouse
- The Leeds Institute of Genetics, Health and Therapeutics, The University of Leeds, Leeds LS2 9NL, UK.
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