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Reich N, Hölscher C. Cholecystokinin (CCK): a neuromodulator with therapeutic potential in Alzheimer's and Parkinson's disease. Front Neuroendocrinol 2024; 73:101122. [PMID: 38346453 DOI: 10.1016/j.yfrne.2024.101122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/04/2024] [Accepted: 01/25/2024] [Indexed: 02/16/2024]
Abstract
Cholecystokinin (CCK) is a neuropeptide modulating digestion, glucose levels, neurotransmitters and memory. Recent studies suggest that CCK exhibits neuroprotective effects in Alzheimer's disease (AD) and Parkinson's disease (PD). Thus, we review the physiological function and therapeutic potential of CCK. The neuropeptide facilitates hippocampal glutamate release and gates GABAergic basket cell activity, which improves declarative memory acquisition, but inhibits consolidation. Cortical CCK alters recognition memory and enhances audio-visual processing. By stimulating CCK-1 receptors (CCK-1Rs), sulphated CCK-8 elicits dopamine release in the substantia nigra and striatum. In the mesolimbic pathway, CCK release is triggered by dopamine and terminates reward responses via CCK-2Rs. Importantly, activation of hippocampal and nigral CCK-2Rs is neuroprotective by evoking AMPK activation, expression of mitochondrial fusion modulators and autophagy. Other benefits include vagus nerve/CCK-1R-mediated expression of brain-derived neurotrophic factor, intestinal protection and suppression of inflammation. We also discuss caveats and the therapeutic combination of CCK with other peptide hormones.
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Affiliation(s)
- Niklas Reich
- The ALBORADA Drug Discovery Institute, University of Cambridge, Island Research Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0AH, UK; Faculty of Health and Medicine, Biomedical & Life Sciences Division, Lancaster University, Lancaster LA1 4YQ, UK.
| | - Christian Hölscher
- Second associated Hospital, Neurology Department, Shanxi Medical University, Taiyuan, Shanxi, China; Henan Academy of Innovations in Medical Science, Neurodegeneration research group, Xinzhen, Henan province, China
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Dengler DG, Sun Q, Harikumar KG, Miller LJ, Sergienko EA. Screening for positive allosteric modulators of cholecystokinin type 1 receptor potentially useful for management of obesity. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2022; 27:384-394. [PMID: 35850480 PMCID: PMC9580343 DOI: 10.1016/j.slasd.2022.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 06/15/2023]
Abstract
Obesity has become a prevailing health burden globally and particularly in the US. It is associated with many health problems, including cardiovascular disease, diabetes and poorer mental health. Hence, there is a high demand to find safe and effective therapeutics for sustainable weight loss. Cholecystokinin (CCK) has been implicated as one of the first gastrointestinal hormones to reduce overeating and suppress appetite by activating the type 1 cholecystokinin receptor (CCK1R). Several drug development campaigns have focused on finding CCK1R-specific agonists, which showed promising efficacy for reducing meal size and weight, but fell short on FDA approval, likely due to side effects associated with potent, long-lasting activation of CCK1Rs. Positive allosteric modulators (PAMs) without inherent agonist activity have been proposed to overcome the shortcomings of traditional, orthosteric agonists and restore CCK1R signaling in failing physiologic systems. However, drug discovery campaigns searching for such novel acting CCK1R agents remain limited. Here we report a high-throughput screening effort and the establishment of a testing funnel, which led to the identification of novel CCK1R modulators. We utilized IP-One accumulation to develop robust functional equilibrium assays tailored to either detect PAMs, agonists or non-specific activators. In addition, we established the CCK1R multiplex PAM assay as a novel method to evaluate functional selectivity capable of recording CCK1R-induced cAMP accumulation and β-arrestin recruitment in the same well. This selection and arrangement of methods enabled the discovery of three scaffolds, which we characterized and validated in an array of functional and binding assays. We found two hits incorporating a tetracyclic scaffold that significantly enhanced CCK signaling at CCK1Rs without intrinsically activating CCK1Rs in an overexpressing system. Our results demonstrate that a well-thought-out testing funnel can identify small molecules with a distinct pharmacological profile and provides an important milestone for the development of novel potential treatments of obesity.
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Affiliation(s)
- Daniela G Dengler
- Conrad Prebys Center for Chemical Genomics, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA.
| | - Qing Sun
- Conrad Prebys Center for Chemical Genomics, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Kaleeckal G Harikumar
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona, USA
| | - Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona, USA.
| | - Eduard A Sergienko
- Conrad Prebys Center for Chemical Genomics, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA.
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Liu Q, Yang D, Zhuang Y, Croll TI, Cai X, Dai A, He X, Duan J, Yin W, Ye C, Zhou F, Wu B, Zhao Q, Xu HE, Wang MW, Jiang Y. Ligand recognition and G-protein coupling selectivity of cholecystokinin A receptor. Nat Chem Biol 2021; 17:1238-1244. [PMID: 34556862 PMCID: PMC8604728 DOI: 10.1038/s41589-021-00841-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 06/24/2021] [Indexed: 02/08/2023]
Abstract
Cholecystokinin A receptor (CCKAR) belongs to family A G-protein-coupled receptors and regulates nutrient homeostasis upon stimulation by cholecystokinin (CCK). It is an attractive drug target for gastrointestinal and metabolic diseases. One distinguishing feature of CCKAR is its ability to interact with a sulfated ligand and to couple with divergent G-protein subtypes, including Gs, Gi and Gq. However, the basis for G-protein coupling promiscuity and ligand recognition by CCKAR remains unknown. Here, we present three cryo-electron microscopy structures of sulfated CCK-8-activated CCKAR in complex with Gs, Gi and Gq heterotrimers, respectively. CCKAR presents a similar conformation in the three structures, whereas conformational differences in the 'wavy hook' of the Gα subunits and ICL3 of the receptor serve as determinants in G-protein coupling selectivity. Our findings provide a framework for understanding G-protein coupling promiscuity by CCKAR and uncover the mechanism of receptor recognition by sulfated CCK-8.
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Affiliation(s)
- Qiufeng Liu
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Dehua Yang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Youwen Zhuang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Tristan I. Croll
- grid.5335.00000000121885934Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Xiaoqing Cai
- grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Antao Dai
- grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Xinheng He
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China
| | - Jia Duan
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China
| | - Wanchao Yin
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Chenyu Ye
- grid.8547.e0000 0001 0125 2443School of Pharmacy, Fudan University, Shanghai, China
| | - Fulai Zhou
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Beili Wu
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.440637.20000 0004 4657 8879School of Life Science and Technology, ShanghaiTech University, Shanghai, China ,grid.9227.e0000000119573309CAS Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing, China
| | - Qiang Zhao
- grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309CAS Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - H. Eric Xu
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.440637.20000 0004 4657 8879School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Ming-Wei Wang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.8547.e0000 0001 0125 2443School of Pharmacy, Fudan University, Shanghai, China ,grid.440637.20000 0004 4657 8879School of Life Science and Technology, ShanghaiTech University, Shanghai, China ,grid.8547.e0000 0001 0125 2443School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yi Jiang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China
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Desai AJ, Mechin I, Nagarajan K, Valant C, Wootten D, Lam PCH, Orry A, Abagyan R, Nair A, Sexton PM, Christopoulos A, Miller LJ. Molecular Basis of Action of a Small-Molecule Positive Allosteric Modulator Agonist at the Type 1 Cholecystokinin Holoreceptor. Mol Pharmacol 2018; 95:245-259. [DOI: 10.1124/mol.118.114082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 12/19/2018] [Indexed: 02/05/2023] Open
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Desai AJ, Miller LJ. Changes in the plasma membrane in metabolic disease: impact of the membrane environment on G protein-coupled receptor structure and function. Br J Pharmacol 2017; 175:4009-4025. [PMID: 28691227 DOI: 10.1111/bph.13943] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/08/2017] [Accepted: 07/04/2017] [Indexed: 12/11/2022] Open
Abstract
Drug development targeting GPCRs often utilizes model heterologous cell expression systems, reflecting an implicit assumption that the membrane environment has little functional impact on these receptors or on their responsiveness to drugs. However, much recent data have illustrated that membrane components can have an important functional impact on intrinsic membrane proteins. This review is directed toward gaining a better understanding of the structure of the plasma membrane in health and disease, and how this organelle can influence GPCR structure, function and regulation. It is important to recognize that the membrane provides a potential mode of lateral allosteric regulation of GPCRs and can affect the effectiveness of drugs and their biological responses in various disease states, which can even vary among individuals across the population. The type 1 cholecystokinin receptor is reviewed as an exemplar of a class A GPCR that is affected in this way by changes in the plasma membrane. LINKED ARTICLES This article is part of a themed section on Molecular Pharmacology of GPCRs. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.21/issuetoc.
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Affiliation(s)
- Aditya J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
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Desai AJ, Dong M, Langlais BT, Dueck AC, Miller LJ. Cholecystokinin responsiveness varies across the population dependent on metabolic phenotype. Am J Clin Nutr 2017; 106:447-456. [PMID: 28592602 PMCID: PMC5525122 DOI: 10.3945/ajcn.117.156943] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 05/05/2017] [Indexed: 11/14/2022] Open
Abstract
Background: Cholecystokinin (CCK) is an important satiety factor, acting at type 1 receptors (CCK1Rs) on vagal afferent neurons; however, CCK agonists have failed clinical trials for obesity. We postulated that CCK1R function might be defective in such patients due to abnormal membrane composition, such as that observed in cholesterol gallstone disease.Objective: Due to the challenges in directly studying CCK1Rs relevant to appetite control, our goal was to develop and apply a method to determine the impact of a patient's own cellular environment on CCK stimulus-activity coupling and to determine whether CCK sensitivity correlated with the metabolic phenotype of a high-risk population.Design: Wild-type CCK1Rs were expressed on leukocytes from 112 Hispanic patients by using adenoviral transduction and 24-h culture, with quantitation of cholesterol composition and intracellular calcium responses to CCK. Results were correlated with clinical, biochemical, and morphometric characteristics.Results: Broad ranges of cellular cholesterol and CCK responsiveness were observed, with elevated cholesterol correlated with reduced CCK sensitivity. This was prominent with increasing degrees of obesity and the presence of diabetes, particularly when poorly controlled. No single standard clinical metric correlated directly with CCK responsiveness. Reduced CCK sensitivity best correlated with elevated serum triglycerides in normal-weight participants and with low HDL concentrations and elevated glycated hemoglobin in obese and diabetic patients.Conclusions: CCK responsiveness varies widely across the population, with reduced signaling in patients with obesity and diabetes. This could explain the failure of CCK agonists in previous clinical trials and supports the rationale to develop corrective modulators to reverse this defective servomechanism for appetite control. This trial was registered at www.clinicaltrials.gov as NCT03121755.
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Affiliation(s)
- Aditya J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics and
| | - Maoqing Dong
- Department of Molecular Pharmacology and Experimental Therapeutics and
| | | | | | - Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics and
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Desai AJ, Dong M, Harikumar KG, Miller LJ. Cholecystokinin-induced satiety, a key gut servomechanism that is affected by the membrane microenvironment of this receptor. INTERNATIONAL JOURNAL OF OBESITY SUPPLEMENTS 2016; 6:S22-S27. [PMID: 28685026 DOI: 10.1038/ijosup.2016.5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The gastrointestinal (GI) tract has a central role in nutritional homeostasis, as location for food ingestion, digestion and absorption, with the gut endocrine system responding to and regulating these events, as well as influencing appetite. One key GI hormone with the full spectrum of these activities is cholecystokinin (CCK), a peptide released from neuroendocrine I cells scattered through the proximal intestine in response to fat and protein, with effects to stimulate gall bladder contraction and pancreatic exocrine secretion, to regulate gastric emptying and intestinal transit, and to induce satiety. There has been interest in targeting the type 1 CCK receptor (CCK1R) for drug development to provide non-caloric satiation as an aid to dieting and weight loss; however, there have been concerns about CCK1R agonists related to side effects and potential trophic impact on the pancreas. A positive allosteric modulator (PAM) of CCK action at this receptor without intrinsic agonist activity could provide a safer and more effective approach to long-term administration. In addition, CCK1R stimulus-activity coupling has been shown to be negatively affected by excess membrane cholesterol, a condition described in the metabolic syndrome, thereby potentially interfering with an important servomechanism regulating appetite. A PAM targeting this receptor could also potentially correct the negative impact of cholesterol on CCK1R function. We will review the molecular basis for binding natural peptide agonist, binding and action of small molecules within the allosteric pocket, and the impact of cholesterol. Novel strategies for taking advantage of this receptor for the prevention and management of obesity will be reviewed.
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Affiliation(s)
- A J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - M Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - K G Harikumar
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - L J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
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Miller LJ, Desai AJ. Metabolic Actions of the Type 1 Cholecystokinin Receptor: Its Potential as a Therapeutic Target. Trends Endocrinol Metab 2016; 27:609-619. [PMID: 27156041 PMCID: PMC4992613 DOI: 10.1016/j.tem.2016.04.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 03/31/2016] [Accepted: 04/05/2016] [Indexed: 12/13/2022]
Abstract
Cholecystokinin (CCK) regulates appetite and reduces food intake by activating the type 1 CCK receptor (CCK1R). Attempts to develop CCK1R agonists for obesity have yielded active agents that have not reached clinical practice. Here we discuss why, along with new strategies to target CCK1R more effectively. We examine signaling events and the possibility of developing agents that exhibit ligand-directed bias, to dissociate satiety activity from undesirable side effects. Potential allosteric sites of modulation are also discussed, along with desired properties of a positive allosteric modulator (PAM) without intrinsic agonist action as another strategy to treat obesity. These new types of CCK1R-active drugs could be useful as standalone agents or as part of a rational drug combination for management of obesity.
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Affiliation(s)
- Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, 85259, USA.
| | - Aditya J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, 85259, USA
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Desai AJ, Dong M, Miller LJ. Beneficial effects of β-sitosterol on type 1 cholecystokinin receptor dysfunction induced by elevated membrane cholesterol. Clin Nutr 2016; 35:1374-1379. [PMID: 27016394 DOI: 10.1016/j.clnu.2016.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 02/09/2016] [Accepted: 03/07/2016] [Indexed: 12/14/2022]
Abstract
BACKGROUND & AIMS The type 1 cholecystokinin receptor (CCK1R) mediates the actions of CCK to support nutritional homeostasis, including post-cibal satiety. However, elevated levels of membrane cholesterol, such as have been observed in metabolic syndrome, interfere with CCK stimulus-activity coupling at the CCK1R, thereby disrupting this important servomechanism. We hypothesize that reversal of the negative impact of cholesterol on this receptor could be useful in the management of obesity. METHODS We have studied the effects of β-sitosterol, a phytosterol structurally related to cholesterol, on CCK receptor function. This included CCK binding and biological activity at wild type CCK1R and CCK2R, as well as at CCK1R in a high cholesterol environment, and at a CCK1R mutant, Y140A, which mimics the behavior of wild type receptor in high cholesterol. RESULTS β-sitosterol (100 μM and 10 μM) significantly improved the defective signaling of the CCK1R present in high cholesterol (p < 0.05), without affecting CCK binding affinity. This effect was absent at the CCK1R present in a normal cholesterol environment, as well as at the structurally-related CCK2R. Furthermore, the cholesterol-insensitive Y140A mutant of CCK1R was resistant to the effects of β-sitosterol. CONCLUSION These data suggest that β-sitosterol affects CCK1R function in high cholesterol by competing with cholesterol at a receptor cholesterol-binding site and may shift its conformation toward normal. This phytosterol extends our understanding of the structure-activity relationships for developing a drug that can target the external surface of CCK1R. Since the concentrations of β-sitosterol shown to be effective in this study are similar to serum levels of this compound achievable during oral administration, it may be worthwhile to study possible beneficial effects of β-sitosterol in metabolic syndrome.
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Affiliation(s)
- Aditya J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ 85259, USA
| | - Maoqing Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ 85259, USA
| | - Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ 85259, USA.
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Affiliation(s)
- Matthew C T Fyfe
- Topivert Limited, Imperial College Incubator, London, United Kingdom
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Desai AJ, Lam PCH, Orry A, Abagyan R, Christopoulos A, Sexton PM, Miller LJ. Molecular Mechanism of Action of Triazolobenzodiazepinone Agonists of the Type 1 Cholecystokinin Receptor. Possible Cooperativity across the Receptor Homodimeric Complex. J Med Chem 2015; 58:9562-77. [PMID: 26654202 DOI: 10.1021/acs.jmedchem.5b01110] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The type 1 cholecystokinin receptor (CCK1R) has multiple physiologic roles relating to nutrient homeostasis, including mediation of postcibal satiety. This effect has been central in efforts to develop agonists of this receptor as part of a program to manage and/or prevent obesity. While a number of small molecule CCK1R agonists have been developed, none have yet been approved for clinical use, based on inadequate efficacy, side effects, or the potential for toxicity. Understanding the molecular details of docking and mechanism of action of these ligands can be helpful in the rational refinement and enhancement of small molecule drug candidates. In the current work, we have defined the mechanism of binding and activity of two triazolobenzodiazepinones, CE-326597 and PF-04756956, which are reported to be full agonist ligands. To achieve this, we utilized receptor binding with a series of allosteric and orthosteric radioligands at structurally related CCK1R and CCK2R, as well as chimeric CCK1R/CCK2R constructs exchanging residues in the allosteric pocket, and assessment of biological activity. These triazolobenzodiazepinones docked within the intramembranous small molecule allosteric ligand pocket, with higher affinity binding to CCK2R than CCK1R, yet with biological activity exclusive to or greatly enhanced at CCK1R. These ligands exhibited cooperativity with benzodiazepine binding across the CCK1R homodimeric complex, resulting in their ability to inhibit only a fraction of the saturable binding of a benzodiazepine radioligand, unlike other small molecule antagonists and agonists of this receptor. This may contribute to the understanding of the unique short duration and reversible gallbladder contraction observed in vivo upon administration of these drugs.
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Affiliation(s)
- Aditya J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic , Scottsdale, Arizona 85259, United States
| | - Polo C H Lam
- Molsoft LLC , La Jolla, California 92037, United States
| | - Andrew Orry
- Molsoft LLC , La Jolla, California 92037, United States
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego , La Jolla, California 92037, United States
| | - Arthur Christopoulos
- Department of Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University , Parkville, Victoria 3052, Australia
| | - Patrick M Sexton
- Department of Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University , Parkville, Victoria 3052, Australia
| | - Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic , Scottsdale, Arizona 85259, United States
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Desai AJ, Dong M, Harikumar KG, Miller LJ. Impact of ursodeoxycholic acid on a CCK1R cholesterol-binding site may contribute to its positive effects in digestive function. Am J Physiol Gastrointest Liver Physiol 2015; 309:G377-86. [PMID: 26138469 PMCID: PMC4556949 DOI: 10.1152/ajpgi.00173.2015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 06/26/2015] [Indexed: 01/31/2023]
Abstract
Dysfunction of the type 1 cholecystokinin (CCK) receptor (CCK1R) as a result of increased gallbladder muscularis membrane cholesterol has been implicated in the pathogenesis of cholesterol gallstones. Administration of ursodeoxycholic acid, which is structurally related to cholesterol, has been shown to have beneficial effects on gallstone formation. Our aims were to explore the possible direct effects and mechanism of action of bile acids on CCK receptor function. We studied the effects of structurally related hydrophobic chenodeoxycholic acid and hydrophilic ursodeoxycholic acid in vitro on CCK receptor function in the setting of normal and elevated membrane cholesterol. We also examined their effects on a cholesterol-insensitive CCK1R mutant (Y140A) disrupting a key site of cholesterol action. The results show that, similar to the impact of cholesterol on CCK receptors, bile acid effects were limited to CCK1R, with no effects on CCK2R. Chenodeoxycholic acid had a negative impact on CCK1R function, while ursodeoxycholic acid had no effect on CCK1R function in normal membranes but was protective against the negative impact of elevated cholesterol on this receptor. The cholesterol-insensitive CCK1R mutant Y140A was resistant to effects of both bile acids. These data suggest that bile acids compete with the action of cholesterol on CCK1R, probably by interacting at the same site, although the conformational impact of each bile acid appears to be different, with ursodeoxycholic acid capable of correcting the abnormal conformation of CCK1R in a high-cholesterol environment. This mechanism may contribute to the beneficial effect of ursodeoxycholic acid in reducing cholesterol gallstone formation.
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Affiliation(s)
- Aditya J. Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona
| | - Maoqing Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona
| | - Kaleeckal G. Harikumar
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona
| | - Laurence J. Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona
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Desai AJ, Henke BR, Miller LJ. Elimination of a cholecystokinin receptor agonist 'trigger' in an effort to develop positive allosteric modulators without intrinsic agonist activity. Bioorg Med Chem Lett 2015; 25:1849-55. [PMID: 25862198 DOI: 10.1016/j.bmcl.2015.03.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 03/17/2015] [Accepted: 03/18/2015] [Indexed: 01/25/2023]
Abstract
Cholecystokinin (CCK) acts at the type 1 cholecystokinin receptor (CCK1R) to elicit satiety and is a well-established drug target for obesity. To date, small molecule agonists have been developed, but have failed to demonstrate adequate efficacy in clinical trials, and concerns about side effects and potential toxicity have limited further development of full agonists. The use of positive allosteric modulators (PAMs) without intrinsic agonist activity that are active only for a brief period of time after a meal might represent a safer alternative. Here, we propose a possible novel strategy to develop such compounds by modifying the agonist 'trigger' of an existing small molecule agonist. We have studied analogues of the 1,5-benzodiazepine agonist, GI181771X, in which the N1-isopropyl agonist 'trigger' was modified. While agonist activity was greatly reduced in these compounds, they acted as negative, rather than positive modulators. The parent drug was also found to exhibit no positive modulation of CCK action. Receptor structure-activity relationship studies demonstrated that the mode of docking these derivatives was distinct from that of the parent compound, perhaps explaining their action as negative allosteric modulators. We conclude that this outcome is likely characteristic of the parental agonist, and that this strategy may be more successfully utilized with a parental ago-PAM, possessing intrinsic positive modulatory activity.
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Affiliation(s)
- Aditya J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, 13400 East Shea Blvd, Scottsdale, AZ 85259, United States
| | - Brad R Henke
- Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKline Inc., Research Triangle Park, NC 27709, United States
| | - Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, 13400 East Shea Blvd, Scottsdale, AZ 85259, United States.
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15
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Abstract
Over the past 30 years, it has been established that hormones produced by the gut, pancreas, and adipose tissue are key players in the control of body weight. These hormones act through a complex neuroendocrine system, including the hypothalamus, to regulate metabolism and energy homeostasis. In obesity, this homeostatic balance is disrupted, either through alterations in the levels of these hormones or through resistance to their actions. Alterations in gut hormone secretion following gastric bypass surgery are likely to underlie the dramatic and persistent loss of weight following this procedure, as well as the observed amelioration in type 2 diabetes mellitus. Medications based on the gut hormone GLP-1 are currently in clinical use to treat type 2 diabetes mellitus and have been shown to produce weight loss. Further therapies for obesity based on other gut hormones are currently in development.
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Affiliation(s)
- Rebecca Scott
- Division of Diabetes, Endocrinology, Metabolism, Hammersmith Hospital, Imperial College London, London, United Kingdom.
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16
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Alén F, Ramírez-López MT, Gómez de Heras R, Rodríguez de Fonseca F, Orio L. Cannabinoid Receptors and Cholecystokinin in Feeding Inhibition. ANOREXIA 2013; 92:165-96. [DOI: 10.1016/b978-0-12-410473-0.00007-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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17
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Abstract
The increasing global prevalence of obesity urgently requires an implementation of efficient preventive and therapeutic measures. Weight loss and its maintenance should be considered one of the most important strategies to reduce the incidence of obesity-related co-morbidities such as diabetes and cardiovascular diseases. Lifestyle modification focused on diet and physical activity represents the essential component of any kind of weight management. However, only an intensive lifestyle intervention can be efficient in terms of long-term weight loss. Anti-obesity drugs affect different targets in the central nervous system or peripheral tissues and improve regulatory and metabolic disturbances that contribute to the development of obesity. Anti-obesity medications provide modest additional fat loss to that achieved by lifestyle modification alone, reduce visceral fat stores, improve programme adherence, weight loss maintenance, diminish obesity-related health risks and improve a quality of life. Anti-obesity drugs do play a role in weight management. Their replacement with placebo is followed by weight regain. Due to adverse events, several anti-obesity drugs were withdrawn from the market over the past few years and currently only orlistat remains available for long-term obesity management. Drug withdrawals, failure of clinical trials with several new anti-obesity compounds as well as inappropriate demands of drug regulating agencies concerning the study protocol led to scepticism about the perspectives in the pharmacotherapy of obesity. However, recently developed anti-obesity medications such as gut hormone analogues and drug combinations provided encouraging results in terms of weight loss, safety and improvement of cardio-metabolic health risks.
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18
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Discovery of new piperidine amide triazolobenzodiazepinones as intestinal-selective CCK1 receptor agonists. Bioorg Med Chem Lett 2012; 22:2943-7. [DOI: 10.1016/j.bmcl.2012.02.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 02/13/2012] [Accepted: 02/16/2012] [Indexed: 11/19/2022]
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19
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Wang L, Hubert JA, Lee SJ, Pan J, Qian S, Reitman ML, Strack AM, Weingarth DT, MacNeil DJ, Weber AE, Edmondson SD. Discovery of pyrimidine carboxamides as potent and selective CCK1 receptor agonists. Bioorg Med Chem Lett 2011; 21:2911-5. [PMID: 21493064 DOI: 10.1016/j.bmcl.2011.03.069] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 03/15/2011] [Accepted: 03/17/2011] [Indexed: 12/30/2022]
Abstract
A series of six-membered heterocycle carboxamides were synthesized and evaluated as cholecystokinin 1 receptor (CCK1R) agonists. A pyrimidine core proved to be the best heterocycle, and SAR studies resulted in the discovery of analog 5, a potent and structurally diverse CCK1R agonist.
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Affiliation(s)
- Liping Wang
- Department of Medicinal Chemistry, Merck & Co. Inc., PO Box 2000, Rahway, NJ 07065, USA.
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