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Geisler CE, Décarie-Spain L, Loh MK, Trumbauer W, Gaisinsky J, Klug ME, Pelletier C, Davis JF, Schmidt HD, Roitman MF, Kanoski SE, Hayes MR. Amylin Modulates a Ventral Tegmental Area-to-Medial Prefrontal Cortex Circuit to Suppress Food Intake and Impulsive Food-Directed Behavior. Biol Psychiatry 2024; 95:938-950. [PMID: 37517705 DOI: 10.1016/j.biopsych.2023.07.011] [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: 02/14/2023] [Revised: 06/23/2023] [Accepted: 07/10/2023] [Indexed: 08/01/2023]
Abstract
BACKGROUND A better understanding of the neural mechanisms regulating impaired satiety to palatable foods is essential to treat hyperphagia linked with obesity. The satiation hormone amylin signals centrally at multiple nuclei including the ventral tegmental area (VTA). VTA-to-medial prefrontal cortex (mPFC) projections encode food reward information to influence behaviors including impulsivity. We hypothesized that modulation of VTA-to-mPFC neurons underlies amylin-mediated decreases in palatable food-motivated behaviors. METHODS We used a variety of pharmacological, behavioral, genetic, and viral approaches (n = 4-16/experiment) to investigate the anatomical and functional circuitry of amylin-controlled VTA-to-mPFC signaling in rats. RESULTS To first establish that VTA amylin receptor (calcitonin receptor) activation can modulate mPFC activity, we showed that intra-VTA amylin decreased food-evoked mPFC cFos. VTA amylin delivery also attenuated food-directed impulsive behavior, implicating VTA amylin signaling as a regulator of mPFC functions. Palatable food activates VTA dopamine and mPFC neurons. Accordingly, dopamine receptor agonism in the mPFC blocked the hypophagic effect of intra-VTA amylin, and VTA amylin injection reduced food-evoked phasic dopamine levels in the mPFC, supporting the idea that VTA calcitonin receptor activation decreases dopamine release in the mPFC. Surprisingly, calcitonin receptor expression was not found on VTA-to-mPFC projecting neurons but was instead found on GABAergic (gamma-aminobutyric acidergic) interneurons in the VTA that provide monosynaptic inputs to this pathway. Blocking intra-VTA GABA signaling, through GABA receptor antagonists and DREADD (designer receptor exclusively activated by designer drugs)-mediated GABAergic neuronal silencing, attenuated intra-VTA amylin-induced hypophagia. CONCLUSIONS These results indicate that VTA amylin signaling stimulates GABA-mediated inhibition of dopaminergic projections to the mPFC to mitigate impulsive consumption of palatable foods.
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Affiliation(s)
- Caroline E Geisler
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Léa Décarie-Spain
- Department of Biological Sciences, Human and Evolutionary Biology Section, University of Southern California, Los Angeles, California
| | - Maxine K Loh
- Department of Psychology, University of Illinois at Chicago, Chicago, Illinois
| | - Wolf Trumbauer
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jane Gaisinsky
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Molly E Klug
- Department of Biological Sciences, Human and Evolutionary Biology Section, University of Southern California, Los Angeles, California
| | - Caitlyn Pelletier
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jon F Davis
- Novo Nordisk Research Center Seattle, Seattle, Washington
| | - Heath D Schmidt
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mitchell F Roitman
- Department of Psychology, University of Illinois at Chicago, Chicago, Illinois
| | - Scott E Kanoski
- Department of Biological Sciences, Human and Evolutionary Biology Section, University of Southern California, Los Angeles, California
| | - Matthew R Hayes
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, Pennsylvania.
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Mazzini G, Le Foll C, Boyle CN, Garelja ML, Zhyvoloup A, Miller MET, Hay DL, Raleigh DP, Lutz TA. The processing intermediate of human amylin, pro-amylin(1-48), has in vivo and in vitro bioactivity. Biophys Chem 2024; 308:107201. [PMID: 38452520 DOI: 10.1016/j.bpc.2024.107201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/31/2024] [Accepted: 02/13/2024] [Indexed: 03/09/2024]
Abstract
Amylin is released by pancreatic beta-cells in response to a meal and its major soluble mature form (37 amino acid-peptide) produces its biological effects by activating amylin receptors. Amylin is derived from larger propeptides that are processed within the synthesizing beta-cell. There are suggestions that a partially processed form, pro-amylin(1-48) is also secreted. We tested the hypothesis that pro-amylin(1-48) has biological activity and that human pro-amylin(1-48) may also form toxic pre-amyloid species. Amyloid formation, the ability to cross-seed and in vitro toxicity were similar between human pro-amylin(1-48) and amylin. Human pro-amylin(1-48) was active at amylin-responsive receptors, though its potency was reduced at rat, but not human amylin receptors. Pro-amylin(1-48) was able to promote anorexia by activating neurons of the area postrema, amylin's primary site of action, indicating that amylin can tolerate significant additions at the N-terminus without losing bioactivity. Our studies help to shed light on the possible roles of pro-amylin(1-48) which may be relevant for the development of future amylin-based drugs.
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Affiliation(s)
- Giulia Mazzini
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Christelle Le Foll
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Christina N Boyle
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Michael L Garelja
- Department of Pharmacology and Toxicology, University of Otago, New Zealand
| | - Alexander Zhyvoloup
- Research Department of Structural and Molecular Biology, University College London, UK
| | | | - Debbie L Hay
- Department of Pharmacology and Toxicology, University of Otago, New Zealand.
| | - Daniel P Raleigh
- Research Department of Structural and Molecular Biology, University College London, UK; Department of Chemistry, Stony Brook University, USA; Laufer Center for Quantitative Biology Stony Brook University, USA.
| | - Thomas A Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
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Huang T, Su J, Wang X, Shi N, Zhang X, He J, Li J, Zhang J, Wang Y. Functional Analysis and Tissue-Specific Expression of Calcitonin and CGRP with RAMP-Modulated Receptors CTR and CLR in Chickens. Animals (Basel) 2024; 14:1058. [PMID: 38612299 PMCID: PMC11010885 DOI: 10.3390/ani14071058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/18/2024] [Accepted: 03/26/2024] [Indexed: 04/14/2024] Open
Abstract
Calcitonin (CT) and calcitonin gene-related peptide (CGRP) are critical regulators of calcium balance and have extensive implications for vertebrate physiological processes. This study explores the CT and CGRP signaling systems in chickens through cloning and characterization of the chicken calcitonin receptor (CTR) and calcitonin receptor-like receptor (CLR), together with three receptor activity-modifying proteins (RAMPs). We illuminated the functional roles for chickens between the receptors examined alone and in RAMP-associated complexes using luciferase reporter assays. Chicken CTRs and CLRs stimulated the cAMP/PKA and MAPK/ERK signaling pathways, signifying their functional receptor status, with CT showing appreciable ligand activity at nanomolar concentrations across receptor combinations. Notably, it is revealed that chicken CLR can act as a functional receptor for CT without or with RAMPs. Furthermore, we uncovered a tissue-specific expression profile for CT, CGRP, CTR, CLR, and RAMPs in chickens, indicating the different physiological roles across various tissues. In conclusion, our data establish a clear molecular basis to reveal information on CT, CGRP, CTR, CLR, and RAMPs in chickens and contribute to understanding the conserved or divergent functions of this family in vertebrates.
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Affiliation(s)
| | | | | | | | | | | | | | - Jiannan Zhang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, College of Life Sciences, Sichuan University, Chengdu 610065, China; (T.H.)
| | - Yajun Wang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, College of Life Sciences, Sichuan University, Chengdu 610065, China; (T.H.)
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Rees TA, Tasma Z, Garelja ML, O'Carroll SJ, Walker CS, Hay DL. Calcitonin receptor, calcitonin gene-related peptide and amylin distribution in C1/2 dorsal root ganglia. J Headache Pain 2024; 25:36. [PMID: 38481170 PMCID: PMC10938748 DOI: 10.1186/s10194-024-01744-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 03/05/2024] [Indexed: 03/17/2024] Open
Abstract
BACKGROUND The upper cervical dorsal root ganglia (DRG) are important for the transmission of sensory information associated with the back of the head and neck, contributing to head pain. Calcitonin receptor (CTR)-based receptors, such as the amylin 1 (AMY1) receptor, and ligands, calcitonin gene-related peptide (CGRP) and amylin, have been linked to migraine and pain. However, the contribution of this system to nociception involving the cervical DRG is unclear. Therefore, this study aimed to determine the relative distribution of the CTR, CGRP, and amylin in upper cervical DRG. METHODS CTR, CGRP, and amylin immunofluorescence was examined relative to neural markers in C1/2 DRG from male and female mice, rats, and human cases. Immunofluorescence was supported by RNA-fluorescence in situ hybridization examining amylin mRNA distribution in rat DRG. RESULTS Amylin immunofluorescence was observed in neuronal soma and fibres. Amylin mRNA (Iapp) was also detected. Amylin and CGRP co-expression was observed in 19% (mouse), 17% (rat), and 36% (human) of DRG neurons in distinct vesicle-like neuronal puncta from one another. CTR immunoreactivity was present in DRG neurons, and both peptides produced receptor signalling in primary DRG cell cultures. CTR-positive neurons frequently co-expressed amylin and/or CGRP (66% rat; 84% human), with some sex differences. CONCLUSIONS Amylin and CGRP could both be local peptide agonists for CTR-based receptors in upper cervical DRG, potentially acting through autocrine and/or paracrine signalling mechanisms to modulate neuron function. Amylin and its receptors could represent novel pain targets.
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Affiliation(s)
- Tayla A Rees
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand
| | - Zoe Tasma
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand
| | - Michael L Garelja
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, 9016, New Zealand
| | - Simon J O'Carroll
- Department of Anatomy and Medical Imaging, Centre for Brain Research, Faculty of Medical and Health Science, University of Auckland, Auckland, 1023, New Zealand
| | - Christopher S Walker
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand
| | - Debbie L Hay
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand.
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, 9016, New Zealand.
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Russo AF, Hay DL. CGRP physiology, pharmacology, and therapeutic targets: migraine and beyond. Physiol Rev 2023; 103:1565-1644. [PMID: 36454715 PMCID: PMC9988538 DOI: 10.1152/physrev.00059.2021] [Citation(s) in RCA: 46] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 11/23/2022] [Accepted: 11/27/2022] [Indexed: 12/03/2022] Open
Abstract
Calcitonin gene-related peptide (CGRP) is a neuropeptide with diverse physiological functions. Its two isoforms (α and β) are widely expressed throughout the body in sensory neurons as well as in other cell types, such as motor neurons and neuroendocrine cells. CGRP acts via at least two G protein-coupled receptors that form unusual complexes with receptor activity-modifying proteins. These are the CGRP receptor and the AMY1 receptor; in rodents, additional receptors come into play. Although CGRP is known to produce many effects, the precise molecular identity of the receptor(s) that mediates CGRP effects is seldom clear. Despite the many enigmas still in CGRP biology, therapeutics that target the CGRP axis to treat or prevent migraine are a bench-to-bedside success story. This review provides a contextual background on the regulation and sites of CGRP expression and CGRP receptor pharmacology. The physiological actions of CGRP in the nervous system are discussed, along with updates on CGRP actions in the cardiovascular, pulmonary, gastrointestinal, immune, hematopoietic, and reproductive systems and metabolic effects of CGRP in muscle and adipose tissues. We cover how CGRP in these systems is associated with disease states, most notably migraine. In this context, we discuss how CGRP actions in both the peripheral and central nervous systems provide a basis for therapeutic targeting of CGRP in migraine. Finally, we highlight potentially fertile ground for the development of additional therapeutics and combinatorial strategies that could be designed to modulate CGRP signaling for migraine and other diseases.
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Affiliation(s)
- Andrew F Russo
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa
- Department of Neurology, University of Iowa, Iowa City, Iowa
- Center for the Prevention and Treatment of Visual Loss, Department of Veterans Affairs Health Center, Iowa City, Iowa
| | - Debbie L Hay
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, Auckland, New Zealand
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El Meouchy P, Wahoud M, Allam S, Chedid R, Karam W, Karam S. Hypertension Related to Obesity: Pathogenesis, Characteristics and Factors for Control. Int J Mol Sci 2022; 23:ijms232012305. [PMID: 36293177 PMCID: PMC9604511 DOI: 10.3390/ijms232012305] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/01/2022] [Accepted: 10/07/2022] [Indexed: 11/16/2022] Open
Abstract
The World Health Organization (WHO) refers to obesity as abnormal or excessive fat accumulation that presents a health risk. Obesity was first designated as a disease in 2012 and since then the cost and the burden of the disease have witnessed a worrisome increase. Obesity and hypertension are closely interrelated as abdominal obesity interferes with the endocrine and immune systems and carries a greater risk for insulin resistance, diabetes, hypertension, and cardiovascular disease. Many factors are at the interplay between obesity and hypertension. They include hemodynamic alterations, oxidative stress, renal injury, hyperinsulinemia, and insulin resistance, sleep apnea syndrome and the leptin-melanocortin pathway. Genetics, epigenetics, and mitochondrial factors also play a major role. The measurement of blood pressure in obese patients requires an adapted cuff and the search for other secondary causes is necessary at higher thresholds than the general population. Lifestyle modifications such as diet and exercise are often not enough to control obesity, and so far, bariatric surgery constitutes the most reliable method to achieve weight loss. Nonetheless, the emergence of new agents such as Semaglutide and Tirzepatide offers promising alternatives. Finally, several molecular pathways are actively being explored, and they should significantly extend the treatment options available.
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Affiliation(s)
- Paul El Meouchy
- Department of Internal Medicine, MedStar Health, Baltimore, MD 21218, USA
| | - Mohamad Wahoud
- Department of Internal Medicine, Tufts Medical Center, Boston, MA 02111, USA
| | - Sabine Allam
- Faculty of Medicine and Medical Sciences, University of Balamand, El Koura P.O. Box 100, Lebanon
| | - Roy Chedid
- College of Osteopathic Medicine, William Carey University, Hattiesburg, MS 39401, USA
| | - Wissam Karam
- Department of Internal Medicine, University of Kansas School of Medicine, Wichita, KS 67214, USA
| | - Sabine Karam
- Division of Nephrology and Hypertension, University of Minnesota, Minneapolis, MN 55414, USA
- Correspondence:
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Garelja ML, Hay DL. A narrative review of the calcitonin peptide family and associated receptors as migraine targets: Calcitonin gene-related peptide and beyond. Headache 2022; 62:1093-1104. [PMID: 36226379 PMCID: PMC9613588 DOI: 10.1111/head.14388] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/08/2022] [Accepted: 06/30/2022] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To summarize the pharmacology of the calcitonin peptide family of receptors and explore their relationship to migraine and current migraine therapies. BACKGROUND Therapeutics that dampen calcitonin gene-related peptide (CGRP) signaling are now in clinical use to prevent or treat migraine. However, CGRP belongs to a broader peptide family, including the peptides amylin and adrenomedullin. Receptors for this family are complex, displaying overlapping pharmacologic profiles. Despite the focus on CGRP and the CGRP receptor in migraine research, recent evidence implicates related peptides and receptors in migraine. METHODS This narrative review summarizes literature encompassing the current pharmacologic understanding of the calcitonin peptide family, and the evidence that links specific members of this family to migraine and migraine-like behaviors. RESULTS Recent work links amylin and adrenomedullin to migraine-like behavior in rodent models and migraine-like attacks in individuals with migraine. We collate novel information that suggests females may be more sensitive to amylin and CGRP in the context of migraine-like behaviors. We report that drugs designed to antagonize the canonical CGRP receptor also antagonize a second CGRP-responsive receptor and speculate as to whether this influences therapeutic efficacy. We also discuss the specificity of current drugs with regards to CGRP isoforms and how this may influence therapeutic profiles. Lastly, we emphasize that receptors related to, but distinct from, the canonical CGRP receptor may represent underappreciated and novel drug targets. CONCLUSION Multiple peptides within the calcitonin family have been linked to migraine. The current focus on CGRP and its canonical receptor may be obscuring pathways to further therapeutics. Drug discovery schemes that take a wider view of the receptor family may lead to the development of new anti-migraine drugs with favorable clinical profiles. We also propose that understanding these related peptides and receptors may improve our interpretation regarding the mechanism of action of current drugs.
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Affiliation(s)
- Michael L. Garelja
- Department of Pharmacology and ToxicologyUniversity of OtagoDunedinNew Zealand
| | - Debbie L. Hay
- Department of Pharmacology and ToxicologyUniversity of OtagoDunedinNew Zealand,Maurice Wilkins Centre for Molecular BiodiscoveryUniversity of AucklandAucklandNew Zealand
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Signaling pathways in obesity: mechanisms and therapeutic interventions. Signal Transduct Target Ther 2022; 7:298. [PMID: 36031641 PMCID: PMC9420733 DOI: 10.1038/s41392-022-01149-x] [Citation(s) in RCA: 78] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/26/2022] [Accepted: 08/08/2022] [Indexed: 12/19/2022] Open
Abstract
Obesity is a complex, chronic disease and global public health challenge. Characterized by excessive fat accumulation in the body, obesity sharply increases the risk of several diseases, such as type 2 diabetes, cardiovascular disease, and nonalcoholic fatty liver disease, and is linked to lower life expectancy. Although lifestyle intervention (diet and exercise) has remarkable effects on weight management, achieving long-term success at weight loss is extremely challenging, and the prevalence of obesity continues to rise worldwide. Over the past decades, the pathophysiology of obesity has been extensively investigated, and an increasing number of signal transduction pathways have been implicated in obesity, making it possible to fight obesity in a more effective and precise way. In this review, we summarize recent advances in the pathogenesis of obesity from both experimental and clinical studies, focusing on signaling pathways and their roles in the regulation of food intake, glucose homeostasis, adipogenesis, thermogenesis, and chronic inflammation. We also discuss the current anti-obesity drugs, as well as weight loss compounds in clinical trials, that target these signals. The evolving knowledge of signaling transduction may shed light on the future direction of obesity research, as we move into a new era of precision medicine.
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Rees TA, Russo AF, O’Carroll SJ, Hay DL, Walker CS. CGRP and the Calcitonin Receptor are Co-Expressed in Mouse, Rat and Human Trigeminal Ganglia Neurons. Front Physiol 2022; 13:860037. [PMID: 35620595 PMCID: PMC9128745 DOI: 10.3389/fphys.2022.860037] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 04/12/2022] [Indexed: 11/23/2022] Open
Abstract
The neuropeptide calcitonin gene-related peptide (CGRP) is expressed in the trigeminal ganglia, a key site in craniofacial pain and migraine. CGRP potently activates two receptors: the CGRP receptor and the AMY1 receptor. These receptors are heterodimers consisting of receptor activity-modifying protein 1 (RAMP1) with either the calcitonin receptor-like receptor (CLR) to form the CGRP receptor or the calcitonin receptor (CTR) to form the AMY1 receptor. The expression of the CGRP receptor in trigeminal ganglia has been described in several studies; however, there is comparatively limited data available describing AMY1 receptor expression and in which cellular subtypes it is found. This research aimed to determine the relative distributions of the AMY1 receptor subunit, CTR, and CGRP in neurons or glia in rat, mouse and human trigeminal ganglia. Antibodies against CTR, CGRP and neuronal/glial cell markers were applied to trigeminal ganglia sections to investigate their distribution. CTR-like and CGRP-like immunoreactivity were observed in both discrete and overlapping populations of neurons. In rats and mice, 30–40% of trigeminal ganglia neurons displayed CTR-like immunoreactivity in their cell bodies, with approximately 78–80% of these also containing CGRP-like immunoreactivity. Although human cases were more variable, a similar overall pattern of CTR-like immunoreactivity to rodents was observed in the human trigeminal ganglia. CTR and CGRP appeared to be primarily colocalized in small to medium sized neurons, suggesting that colocalization of CTR and CGRP may occur in C-fiber neurons. CGRP-like or CTR-like immunoreactivity were not typically observed in glial cells. Western blotting confirmed that CTR was expressed in the trigeminal ganglia of all three species. These results confirm that CTR is expressed in trigeminal ganglia neurons. The identification of populations of neurons that express both CGRP and CTR suggests that CGRP could act in an autocrine manner through a CTR-based receptor, such as the AMY1 receptor. Overall, this suggests that a trigeminal ganglia CTR-based receptor may be activated during migraine and could therefore represent a potential target to develop treatments for craniofacial pain and migraine.
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Affiliation(s)
- Tayla A. Rees
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - Andrew F. Russo
- Department of Molecular Physiology and Biophysics, Center for the Prevention and Treatment of Visual Loss, Veterans Administration Health Center, Department of Neurology, University of Iowa, Iowa City, IA, United States
| | - Simon J. O’Carroll
- Department of Anatomy and Medical Imaging and Centre for Brain Research, Faculty of Medical and Health Science, University of Auckland, Auckland, New Zealand
| | - Debbie L. Hay
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand
- *Correspondence: Debbie L. Hay, ; Christopher S. Walker,
| | - Christopher S. Walker
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
- *Correspondence: Debbie L. Hay, ; Christopher S. Walker,
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Mathiesen DS, Lund A, Holst JJ, Knop FK, Lutz TA, Bagger JI. THERAPY OF ENDOCRINE DISEASE: Amylin and calcitonin - physiology and pharmacology. Eur J Endocrinol 2022; 186:R93-R111. [PMID: 35353712 DOI: 10.1530/eje-21-1261] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 03/30/2022] [Indexed: 11/08/2022]
Abstract
Type 2 diabetes is a common manifestation of metabolic dysfunction due to obesity and constitutes a major burden for modern health care systems, in concert with the alarming rise in obesity worldwide. In recent years, several successful pharmacotherapies improving glucose metabolism have emerged and some of these also promote weight loss, thus, ameliorating insulin resistance. However, the progressive nature of type 2 diabetes is not halted by these new anti-diabetic pharmacotherapies. Therefore, novel therapies promoting weight loss further and delaying diabetes progression are needed. Amylin, a beta cell hormone, has satiating properties and also delays gastric emptying and inhibits postprandial glucagon secretion with the net result of reducing postprandial glucose excursions. Amylin acts through the six amylin receptors, which share the core component with the calcitonin receptor. Calcitonin, derived from thyroid C cells, is best known for its role in humane calcium metabolism, where it inhibits osteoclasts and reduces circulating calcium. However, calcitonin, particularly of salmon origin, has also been shown to affect insulin sensitivity, reduce the gastric emptying rate and promote satiation. Preclinical trials with agents targeting the calcitonin receptor and the amylin receptors, show improvements in several parameters of glucose metabolism including insulin sensitivity and some of these agents are currently undergoing clinical trials. Here, we review the physiological and pharmacological effects of amylin and calcitonin and discuss the future potential of amylin and calcitonin-based treatments for patients with type 2 diabetes and obesity.
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Affiliation(s)
- David S Mathiesen
- Center for Clinical Metabolic Research, Gentofte Hospital, Hellerup, Denmark
| | - Asger Lund
- Center for Clinical Metabolic Research, Gentofte Hospital, Hellerup, Denmark
- Department of Medicine, Gentofte and Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip K Knop
- Center for Clinical Metabolic Research, Gentofte Hospital, Hellerup, Denmark
- Department of Medicine, Gentofte and Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Steno Diabetes Center Copenhagen, Gentofte, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas A Lutz
- Institute of Veterinary Physiology, Vetsuisse-Faculty, University of Zurich, Zurich, Switzerland
| | - Jonatan I Bagger
- Center for Clinical Metabolic Research, Gentofte Hospital, Hellerup, Denmark
- Department of Medicine, Gentofte and Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Steno Diabetes Center Copenhagen, Gentofte, Denmark
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Mediators of Amylin Action in Metabolic Control. J Clin Med 2022; 11:jcm11082207. [PMID: 35456307 PMCID: PMC9025724 DOI: 10.3390/jcm11082207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/08/2022] [Accepted: 04/13/2022] [Indexed: 02/06/2023] Open
Abstract
Amylin (also called islet amyloid polypeptide (IAPP)) is a pancreatic beta-cell hormone that is co-secreted with insulin in response to nutrient stimuli. The last 35 years of intensive research have shown that amylin exerts important physiological effects on metabolic control. Most importantly, amylin is a physiological control of meal-ending satiation, and it limits the rate of gastric emptying and reduces the secretion of pancreatic glucagon, in particular in postprandial states. The physiological effects of amylin and its analogs are mediated by direct brain activation, with the caudal hindbrain playing the most prominent role. The clarification of the structure of amylin receptors, consisting of the calcitonin core receptor plus receptor-activity modifying proteins, aided in the development of amylin analogs with a broad pharmacological profile. The general interest in amylin physiology and pharmacology was boosted by the finding that amylin is a sensitizer to the catabolic actions of leptin. Today, amylin derived analogs are considered to be among the most promising approaches for the pharmacotherapy against obesity. At least in conjunction with insulin, amylin analogs are also considered important treatment options in diabetic patients, so that new drugs may soon be added to the only currently approved compound pramlintide (Symlin®). This review provides a brief summary of the physiology of amylin’s mode of actions and its role in the control of the metabolism, in particular energy intake and glucose metabolism.
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Liu D, Chang L, Wang J, Zhu Q, Jiang N, Azhar M, Ahmed A, Zeng G. Effect of Xiongmatang Extract on Behavioral and TRPV1-CGRP/CGRP-R Pathway in Rats With Migraine. Front Pharmacol 2022; 13:835187. [PMID: 35350752 PMCID: PMC8957915 DOI: 10.3389/fphar.2022.835187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
Migraine is a complex neurovascular disease, which seriously affects the quality of life in patients. This study aimed to evaluate the effect of Xiongmatang (XMT) extract on rats with migraine induced by inflammatory soup and the underlying mechanisms. First, 1 week after dural catheterization, inflammatory soup was injected through a microsyringe to stimulate the dura of rats for 6 times (12 days), once every 2 days, 10 μL each time, to establish a migraine model. According to pain threshold analysis, behavioral change detection, and pathological analysis, the effects of XMT extract on rats with migraine were evaluated. The positive, mRNA and protein expression of related factors were detected by immunohistochemistry, RT-QPCR, and Western blot analysis to elucidate the underlying mechanism. XMT extract improved the behavioral performance of rats, and improve the pathological changes in the trigeminal nerve in rats. Further experimental results show that XMT extract regulated the expression of migraine-related factors in the trigeminal nerve, manifested as transient receptor potential vanilloid 1 (TRPV1), calcitonin-gene-related peptide (CGRP), calcitonin receptor-like receptor (CRLR), and receptor activity-modifying protein 1 (RAMP1) positive expression, mRNA expression, and protein expression reduction. XMT extract can significantly improved the behavioral performance of rats with migraine, and its mechanism of action might involve regulating the activity of TRPV1-CGRP/CGRP-R pathway.
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Affiliation(s)
- Dingding Liu
- College of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Lulu Chang
- College of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Jingru Wang
- College of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Qiang Zhu
- College of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Ning Jiang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Mudassar Azhar
- Dr. Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological Sciences University of Karachi, Karachi, Pakistan
| | - Ayaz Ahmed
- Dr. Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological Sciences University of Karachi, Karachi, Pakistan
| | - Guirong Zeng
- Hunan Key Laboratory of Pharmacodynamics and Safety Evaluation of New Drugs and Hunan Provincial Research Center for Safety Evaluation of Drugs, Changsha, China
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Garelja ML, Bower RL, Brimble MA, Chand S, Harris PW, Jamaluddin MA, Petersen J, Siow A, Walker CS, Hay DL. Pharmacological characterisation of mouse calcitonin and calcitonin receptor-like receptors reveals differences compared with human receptors. Br J Pharmacol 2022; 179:416-434. [PMID: 34289083 PMCID: PMC8776895 DOI: 10.1111/bph.15628] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 06/17/2021] [Accepted: 07/12/2021] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND AND PURPOSE The calcitonin (CT) receptor family is complex, comprising two receptors (the CT receptor [CTR] and the CTR-like receptor [CLR]), three accessory proteins (RAMPs) and multiple endogenous peptides. This family contains several important drug targets, including CGRP, which is targeted by migraine therapeutics. The pharmacology of this receptor family is poorly characterised in species other than rats and humans. To facilitate understanding of translational and preclinical data, we need to know the receptor pharmacology of this family in mice. EXPERIMENTAL APPROACH Plasmids encoding mouse CLR/CTR and RAMPs were transiently transfected into Cos-7 cells. cAMP production was measured in response to agonists in the absence or presence of antagonists. KEY RESULTS We report the first synthesis and characterisation of mouse adrenomedullin, adrenomedullin 2 and βCGRP and of mouse CTR without or with mouse RAMPs. Receptors containing m-CTR had subtly different pharmacology than human receptors; they were promiscuous in their pharmacology, both with and without RAMPs. Several peptides, including mouse αCGRP and mouse adrenomedullin 2, were potent agonists of the m-CTR:m-RAMP3 complex. Pharmacological profiles of receptors comprising m-CLR:m-RAMPs were generally similar to those of their human counterparts, albeit with reduced specificity. CONCLUSION AND IMPLICATIONS Mouse receptor pharmacology differed from that in humans, with mouse receptors displaying reduced discrimination between ligands. This creates challenges for interpreting which receptor may underlie an effect in preclinical models and thus translation of findings from mice to humans. It also highlights the need for new ligands to differentiate between these complexes. LINKED ARTICLES This article is part of a themed issue on Advances in Migraine and Headache Therapy (BJP 75th Anniversary).. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.3/issuetoc.
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Affiliation(s)
- Michael L. Garelja
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, 9016, New Zealand,School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Rebekah L Bower
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Margaret A. Brimble
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand,School of Chemical Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Shanan Chand
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Paul W.R. Harris
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand,School of Chemical Sciences, University of Auckland, Auckland, 1010, New Zealand
| | | | - Jakeb Petersen
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Andrew Siow
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand,School of Chemical Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Christopher S. Walker
- School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand
| | - Debbie L. Hay
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, 9016, New Zealand,School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, 1010, New Zealand,Author to whom correspondence should be addressed,
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Müller TD, Blüher M, Tschöp MH, DiMarchi RD. Anti-obesity drug discovery: advances and challenges. Nat Rev Drug Discov 2022; 21:201-223. [PMID: 34815532 PMCID: PMC8609996 DOI: 10.1038/s41573-021-00337-8] [Citation(s) in RCA: 331] [Impact Index Per Article: 165.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2021] [Indexed: 12/27/2022]
Abstract
Enormous progress has been made in the last half-century in the management of diseases closely integrated with excess body weight, such as hypertension, adult-onset diabetes and elevated cholesterol. However, the treatment of obesity itself has proven largely resistant to therapy, with anti-obesity medications (AOMs) often delivering insufficient efficacy and dubious safety. Here, we provide an overview of the history of AOM development, focusing on lessons learned and ongoing obstacles. Recent advances, including increased understanding of the molecular gut-brain communication, are inspiring the pursuit of next-generation AOMs that appear capable of safely achieving sizeable and sustained body weight loss.
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Affiliation(s)
- Timo D. Müller
- grid.4567.00000 0004 0483 2525Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, Neuherberg, Germany ,grid.452622.5German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Matthias Blüher
- grid.411339.d0000 0000 8517 9062Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
| | - Matthias H. Tschöp
- grid.4567.00000 0004 0483 2525Helmholtz Zentrum München, Neuherberg, Germany ,grid.6936.a0000000123222966Division of Metabolic Diseases, Department of Medicine, Technische Universität München, München, Germany
| | - Richard D. DiMarchi
- grid.411377.70000 0001 0790 959XDepartment of Chemistry, Indiana University, Bloomington, IN USA
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15
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Corrigan RR, Piontkivska H, Casadesus G. Amylin Pharmacology in Alzheimer's Disease Pathogenesis and Treatment. Curr Neuropharmacol 2022; 20:1894-1907. [PMID: 34852745 PMCID: PMC9886804 DOI: 10.2174/1570159x19666211201093147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/12/2021] [Accepted: 11/26/2021] [Indexed: 11/22/2022] Open
Abstract
The metabolic peptide hormone amylin, in concert with other metabolic peptides like insulin and leptin, has an important role in metabolic homeostasis and has been intimately linked to Alzheimer's disease (AD). Interestingly, this pancreatic amyloid peptide is known to self-aggregate much like amyloid-beta and has been reported to be a source of pathogenesis in both Type II diabetes mellitus (T2DM) and Alzheimer's disease. The traditional "gain of toxic function" properties assigned to amyloid proteins are, however, contrasted by several reports highlighting neuroprotective effects of amylin and a recombinant analog, pramlintide, in the context of these two diseases. This suggests that pharmacological therapies aimed at modulating the amylin receptor may be therapeutically beneficial for AD development, as they already are for T2DMM. However, the nature of amylin receptor signaling is highly complex and not well studied in the context of CNS function. Therefore, to begin to address this pharmacological paradox in amylin research, the goal of this review is to summarize the current research on amylin signaling and CNS functions and critically address the paradoxical nature of this hormone's signaling in the context of AD pathogenesis.
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Affiliation(s)
| | | | - Gemma Casadesus
- Address correspondence to this author at the Department of Pharmacology and Therapeutics, University of Florida, PO Box 100495. Gainesville, FL32610 USA; Tel: 352-294-5346; E-mail:
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Jin YJ, Chennupati R, Li R, Liang G, Wang S, Iring A, Graumann J, Wettschureck N, Offermanns S. Protein kinase N2 mediates flow-induced endothelial NOS activation and vascular tone regulation. J Clin Invest 2021; 131:e145734. [PMID: 34499618 DOI: 10.1172/jci145734] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 09/01/2021] [Indexed: 01/31/2023] Open
Abstract
Formation of NO by endothelial NOS (eNOS) is a central process in the homeostatic regulation of vascular functions including blood pressure regulation, and fluid shear stress exerted by the flowing blood is a main stimulus of eNOS activity. Previous work has identified several mechanosensing and -transducing processes in endothelial cells, which mediate this process and induce the stimulation of eNOS activity through phosphorylation of the enzyme via various kinases including AKT. How the initial mechanosensing and signaling processes are linked to eNOS phosphorylation is unclear. In human endothelial cells, we demonstrated that protein kinase N2 (PKN2), which is activated by flow through the mechanosensitive cation channel Piezo1 and Gq/G11-mediated signaling, as well as by Ca2+ and phosphoinositide-dependent protein kinase 1 (PDK1), plays a pivotal role in this process. Active PKN2 promoted the phosphorylation of human eNOS at serine 1177 and at a newly identified site, serine 1179. These phosphorylation events additively led to increased eNOS activity. PKN2-mediated eNOS phosphorylation at serine 1177 involved the phosphorylation of AKT synergistically with mTORC2-mediated AKT phosphorylation, whereas active PKN2 directly phosphorylated human eNOS at serine 1179. Mice with induced endothelium-specific deficiency of PKN2 showed strongly reduced flow-induced vasodilation and developed arterial hypertension accompanied by reduced eNOS activation. These results uncover a central mechanism that couples upstream mechanosignaling processes in endothelial cells to the regulation of eNOS-mediated NO formation, vascular tone, and blood pressure.
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Affiliation(s)
- Young-June Jin
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Ramesh Chennupati
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Rui Li
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Guozheng Liang
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - ShengPeng Wang
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Yanta District, Xi'an, China
| | - András Iring
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Laboratory of Molecular Medicine, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Johannes Graumann
- Scientific Service Group Biomolecular Mass Spectrometry, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Nina Wettschureck
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Centre for Molecular Medicine, Medical Faculty, JW Goethe University Frankfurt, Frankfurt, Germany.,Cardiopulmonary Institute (CPI), Frankfurt, Germany.,German Center for Cardiovascular Research (DZHK), Rhine-Main Site, Frankfurt and Bad Nauheim, Germany
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Centre for Molecular Medicine, Medical Faculty, JW Goethe University Frankfurt, Frankfurt, Germany.,Cardiopulmonary Institute (CPI), Frankfurt, Germany.,German Center for Cardiovascular Research (DZHK), Rhine-Main Site, Frankfurt and Bad Nauheim, Germany
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Leung L, Liao S, Wu C. To Probe the Binding Interactions between Two FDA Approved Migraine Drugs (Ubrogepant and Rimegepant) and Calcitonin-Gene Related Peptide Receptor (CGRPR) Using Molecular Dynamics Simulations. ACS Chem Neurosci 2021; 12:2629-2642. [PMID: 34184869 DOI: 10.1021/acschemneuro.1c00135] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Recently, the FDA approved ubrogepant and rimegepant as oral drugs to treat migraines by targeting the calcitonin-gene related peptide receptor (CGRPR). Unfortunately, there is no high-resolution complex structure with these two drugs; thus the detailed interaction between drugs and the receptor remains elusive. This study uses molecular docking and molecular dynamics simulation to model the drug-receptor complex and analyze their binding interactions at a molecular level. The complex crystal structure (3N7R) of the gepant drugs' predecessor, olcegepant, was used for our molecular docking of the two drugs and served as a control system. The three systems, with ubrogepant, rimegepant, and crystal olcegepant, were subject to 3 × 1000 ns molecular dynamics simulations and followed by the simulation interaction diagram (SID), structural clustering, and MM-GBSA binding energy analyses. Our MD data revealed that olcegepant binds most strongly to the CGRPR, followed by ubrogepant and then rimegepant, largely due to changes in hydrophobic and electrostatic interactions. The order of our MM-GBSA binding energies of these three compounds is consistent with their experimental IC50 values. SID analysis revealed the pharmacophore of the gepant class to be the dihydroquinazolinone group derivative. Subtle differences in interaction profile have been noted, including interactions with the W74 and W72 residues. The ubrogepant and rimegepant both contact A70 and M42 of the receptor, while olcegepant does not. The results of this study elucidate the interactions in the binding pocket of CGRP receptor and can assist in further development for orally available antagonists of the CGRP receptor.
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Affiliation(s)
- Lauren Leung
- College of Letters and Sciences, University of California, Santa Barbara, Santa Barbara, California 93107, United States
| | - Siyan Liao
- Key Laboratory of Molecular Target & Clinical Pharmacology, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou 511436, China
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
| | - Chun Wu
- Key Laboratory of Molecular Target & Clinical Pharmacology, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou 511436, China
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
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18
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The calcitonin receptor is the main mediator of LAAMA's body weight lowering effects in male mice. Eur J Pharmacol 2021; 908:174352. [PMID: 34274340 DOI: 10.1016/j.ejphar.2021.174352] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/08/2021] [Accepted: 07/12/2021] [Indexed: 11/21/2022]
Abstract
The anorectic action of the pancreatic hormone amylin is mainly mediated through the area postrema (AP). Amylin activates AP neurons using a heterodimeric receptor (AMY) composed of the calcitonin receptor (CTR) and the receptor activity modifying protein (RAMP 1, 2 or 3). The aim of the following experiments is to test the effects of the long acting amylin analogue (LAAMA) in RAMP1/3 knock-out (KO) male mice and in neuronal CTR KO Nestin-CreCTR male mice. In vitro, LAAMA exerted an equipotent effect on CTR and AMYs that was maintained across species. Following one week of 45% high fat diet, WT, RAMP1/3 KO and Nestin-CreCTR mice were injected daily for one week with vehicle or LAAMA. LAAMA decreased body weight gain in WT and in RAMP1/3 KO mice suggesting that RAMP1/3 are not necessary for LAAMA-induced effects. However, LAAMA was not able to produce any body lowering and anorectic effects in Nestin-CreCTR mice. This was accompanied by the absence of any c-Fos signal in the AP opposite to WT control mice. Together, these results suggest that LAAMA's effects are mainly mediated through CTR rather than specific AMY. The study of LAAMA or any amylin receptor agonist in different receptor KO mouse models helps disentangle the underlying mechanisms used by these molecules.
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Mietlicki-Baase EG, Santollo J, Daniels D. Fluid intake, what's dopamine got to do with it? Physiol Behav 2021; 236:113418. [PMID: 33838203 DOI: 10.1016/j.physbeh.2021.113418] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/12/2021] [Accepted: 04/05/2021] [Indexed: 12/27/2022]
Abstract
Maintaining fluid balance is critical for life. The central components that control fluid intake are only partly understood. This contribution to the collection of papers highlighting work by members of the Society for the Study of Ingestive Behavior focuses on the role that dopamine has on fluid intake and describes the roles that various bioregulators can have on thirst and sodium appetite by influencing dopamine systems in the brain. The goal of the review is to highlight areas in need of more research and to propose a framework to guide that research. We hope that this framework will inspire researchers in the field to investigate these interesting questions in order to form a more complete understanding of how fluid intake is controlled.
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Affiliation(s)
- Elizabeth G Mietlicki-Baase
- Department of Exercise and Nutrition Sciences, University at Buffalo, State University of New York, Buffalo, NY 14214, United States; Center for Ingestive Behavior Research, University at Buffalo, State University of New York, Buffalo, NY 14260, United States
| | - Jessica Santollo
- Department of Biology, University of Kentucky, Lexington, KY 40506, United States
| | - Derek Daniels
- Center for Ingestive Behavior Research, University at Buffalo, State University of New York, Buffalo, NY 14260, United States; Department of Psychology, University at Buffalo, State University of New York, Buffalo, NY 14260, United States
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Abstract
PURPOSE OF REVIEW As a chronic and relapsing disease, obesity impairs metabolism and causes cardiovascular diseases. Although behavioral modification is important for the treatment of obesity, it is difficult to achieve an ideal weight or sustain the process of long-term weight loss. Therefore, the obesity control guidelines strongly recommend lifestyle interventions along with medical treatment for patients who are overweight. There is sufficient evidence supporting that pharmacotherapy in combination with behavior-based interventions can result in significant weight loss and improved cardiometabolism. RECENT FINDINGS Recent meta-analyses of new anti-obesity drugs and their weight-loss efficacy have shown that the overall placebo-subtracted weight reduction (%) for at least 12 months ranged from 2.9 to 6.8% for the following drugs: phentermine/topiramate (6.8%), liraglutide (5.4%), naltrexone/bupropion (4.0%), orlistat (2.9%), and lorcaserin (3.1%). However, very recently, on February 13, 2020, the US Food and Drug Administration (FDA) ordered the withdrawal of lorcaserin from markets, as a clinical trial to assess drug safety showed an increased risk of cancer. Currently, the anti-obesity medications that have been approved by the FDA for chronic weight management are orlistat, phentermine/topiramate, naltrexone/bupropion, and liraglutide. However, they are costly and may have adverse effects in some individuals. Therefore, drug therapy should be initiated in obese individuals after weighing its benefits and risks. One of the strategies for long-term obesity control is that anti-obesity medications should be tailored for specific patients depending on their chronic conditions, comorbidities, and preferences.
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Affiliation(s)
- Young Jin Tak
- Department of Family Medicine, Pusan National University Hospital, Busan, 49241, South Korea
- Biomedical Research Institute, Pusan National University Hospital, Busan, 49241, South Korea
| | - Sang Yeoup Lee
- Family Medicine Clinic and Research Institute of Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, 50612, South Korea.
- Department of Medical Education, Pusan National University School of Medicine, Yangsan, 50612, South Korea.
- Integrated Research Institute for Natural Ingredients and Functional Foods, Yangsan, 50612, South Korea.
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Mono and dual agonists of the amylin, calcitonin, and CGRP receptors and their potential in metabolic diseases. Mol Metab 2020; 46:101109. [PMID: 33166741 PMCID: PMC8085567 DOI: 10.1016/j.molmet.2020.101109] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Therapies for metabolic diseases are numerous, yet improving insulin sensitivity beyond that induced by weight loss remains challenging. Therefore, search continues for novel treatment candidates that can stimulate insulin sensitivity and increase weight loss efficacy in combination with current treatment options. Calcitonin gene-related peptide (CGRP) and amylin belong to the same peptide family and have been explored as treatments for metabolic diseases. However, their full potential remains controversial. SCOPE OF REVIEW In this article, we introduce this rather complex peptide family and its corresponding receptors. We discuss the physiology of the peptides with a focus on metabolism and insulin sensitivity. We also thoroughly review the pharmacological potential of amylin, calcitonin, CGRP, and peptide derivatives as treatments for metabolic diseases, emphasizing their ability to increase insulin sensitivity based on preclinical and clinical studies. MAJOR CONCLUSIONS Amylin receptor agonists and dual amylin and calcitonin receptor agonists are relevant treatment candidates, especially because they increase insulin sensitivity while also assisting weight loss, and their unique mode of action complements incretin-based therapies. However, CGRP and its derivatives seem to have only modest if any metabolic effects and are no longer of interest as therapies for metabolic diseases.
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Giani L, Proietti Cecchini A, Leone M. Galcanezumab for the prevention of cluster headache. Expert Opin Biol Ther 2020; 20:1133-1142. [PMID: 32702245 DOI: 10.1080/14712598.2020.1800635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Cluster headache (CH) is among the worst painful conditions. The available therapies are scarce and not specific, leaving many patients unsatisfied because of poor efficacy and/or tolerability. Patients not responding to common treatments are offered semi-invasive and invasive procedures with uncertain results. Based on the current understanding of CH pathophysiology, new possible therapeutic approaches come from drugs interfering with Calcitonin Gene Related Peptide (CGRP). AREAS COVERED After summarizing the evidence for CGRP involvement in CH pathophysiology, we review the published literature (PubMed) and information (clinicaltrials.gov, EudraCT, EMA and FDA websites) regarding a novel anti-CGRP monoclonal antibody, Galcanezumab, its pharmacological properties, development, and evidence for the treatment of CH. Publications regarding other indications (migraine) are considered for completeness and safety/tolerability profile. EXPERT OPINION In one randomized clinical trial, Galcanezumab has proven to be effective and safe as a preventive treatment in episodic CH, with a favorable tolerability profile offering a potential new option in the therapeutic arsenal. Inefficacy of galcanezumab in chronic CH as well as the inefficacy of another monoclonal antibody against CGRP (fremanezumab) in both episodic and chronic CH question the scalability of the drug in CH management. Further, studies comparing galcanezumab to the current standard treatments are highly desirable.
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Affiliation(s)
- Luca Giani
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta" , 20133, Milano (MI), Italy
| | | | - Massimo Leone
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta" , 20133, Milano (MI), Italy
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Distributed amylin receptor signaling and its influence on motivated behavior. Physiol Behav 2020; 222:112958. [DOI: 10.1016/j.physbeh.2020.112958] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/11/2020] [Accepted: 04/30/2020] [Indexed: 12/11/2022]
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Foll CL, Lutz TA. Systemic and Central Amylin, Amylin Receptor Signaling, and Their Physiological and Pathophysiological Roles in Metabolism. Compr Physiol 2020; 10:811-837. [PMID: 32941692 DOI: 10.1002/cphy.c190034] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This article in the Neural and Endocrine Section of Comprehensive Physiology discusses the physiology and pathophysiology of the pancreatic hormone amylin. Shortly after its discovery in 1986, amylin has been shown to reduce food intake as a satiation signal to limit meal size. Amylin also affects food reward, sensitizes the brain to the catabolic actions of leptin, and may also play a prominent role in the development of certain brain areas that are involved in metabolic control. Amylin may act at different sites in the brain in addition to the area postrema (AP) in the caudal hindbrain. In particular, the sensitizing effect of amylin on leptin action may depend on a direct interaction in the hypothalamus. The concept of central pathways mediating amylin action became more complex after the discovery that amylin is also synthesized in certain hypothalamic areas but the interaction between central and peripheral amylin signaling remains currently unexplored. Amylin may also play a dominant pathophysiological role that is associated with the aggregation of monomeric amylin into larger, cytotoxic molecular entities. This aggregation in certain species may contribute to the development of type 2 diabetes mellitus but also cardiovascular disease. Amylin receptor pharmacology is complex because several distinct amylin receptor subtypes have been described, because other neuropeptides [e.g., calcitonin gene-related peptide (CGRP)] can also bind to amylin receptors, and because some components of the functional amylin receptor are also used for other G-protein coupled receptor (GPCR) systems. © 2020 American Physiological Society. Compr Physiol 10:811-837, 2020.
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Affiliation(s)
- Christelle Le Foll
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Thomas A Lutz
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
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Zakariassen HL, John LM, Lutz TA. Central control of energy balance by amylin and calcitonin receptor agonists and their potential for treatment of metabolic diseases. Basic Clin Pharmacol Toxicol 2020; 127:163-177. [PMID: 32363722 DOI: 10.1111/bcpt.13427] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/28/2020] [Accepted: 04/28/2020] [Indexed: 12/13/2022]
Abstract
The prevalence of obesity and associated comorbidities such as type 2 diabetes and cardiovascular disease is increasing globally. Body-weight loss reduces the risk of morbidity and mortality in obese individuals, and thus, pharmacotherapies that induce weight loss can be of great value in improving the health and well-being of people living with obesity. Treatment with amylin and calcitonin receptor agonists reduces food intake and induces weight loss in several animal models, and a number of companies have started clinical testing for peptide analogues in the treatment of obesity and/or type 2 diabetes. Studies predominantly performed in rodent models show that amylin and the dual amylin/calcitonin receptor agonist salmon calcitonin achieve their metabolic effects by engaging areas in the brain associated with regulating homeostatic energy balance. In particular, signalling via neuronal circuits in the caudal hindbrain and the hypothalamus is implicated in mediating effects on food intake and energy expenditure. We review the current literature investigating the interaction of amylin/calcitonin receptor agonists with neurocircuits that induce the observed metabolic effects. Moreover, the status of drug development of amylin and calcitonin receptor agonists for the treatment of metabolic diseases is summarized.
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Affiliation(s)
- Hannah Louise Zakariassen
- Section of Experimental Animal Models, Department of Veterinary and Animal Science, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark.,Obesity Pharmacology, Novo Nordisk A/S, Måløv, Denmark
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26
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Aftabizadeh M, Tatarek-Nossol M, Andreetto E, El Bounkari O, Kipp M, Beyer C, Latz E, Bernhagen J, Kapurniotu A. Blocking Inflammasome Activation Caused by β-Amyloid Peptide (Aβ) and Islet Amyloid Polypeptide (IAPP) through an IAPP Mimic. ACS Chem Neurosci 2019; 10:3703-3717. [PMID: 31295403 DOI: 10.1021/acschemneuro.9b00260] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Inflammation in the brain and pancreas is linked to cell degeneration and pathogenesis of both Alzheimer's disease (AD) and type 2 diabetes (T2D). Inflammatory cascades in both tissues are triggered by the uptake of β-amyloid peptide (Aβ) or islet amyloid polypeptide (IAPP) aggregates by microglial cells (AD) or macrophages (T2D) and their insufficient lysosomal degradation. This results in lysosomal damage, caspase-1/NLRP3 inflammasome activation and release of interleukin-1β (IL-1β), a key proinflammatory cytokine in both diseases. Here we show that the inflammatory processes mediated by Aβ and IAPP aggregates in microglial cells and macrophages are blocked by IAPP-GI, a nonamyloidogenic IAPP mimic, which forms high-affinity soluble and nonfibrillar hetero-oligomers with both polypeptides. In contrast to fibrillar Aβ aggregates, nonfibrillar Aβ/IAPP-GI or Aβ/IAPP hetero-oligomers become rapidly internalized by microglial cells and targeted to lysosomes where Aβ is fully degraded. Internalization occurs via IAPP receptor-mediated endocytosis. Moreover, in contrast to IAPP aggregates, IAPP/IAPP-GI hetero-oligomers become rapidly internalized and degraded in the lysosomal compartments of macrophages. Our findings uncover a previously unknown function for the IAPP/Aβ cross-amyloid interaction and suggest that conversion of Aβ or IAPP into lysosome-targeted and easily degradable hetero-oligomers by heteroassociation with IAPP mimics could become a promising approach to specifically prevent amyloid-mediated inflammation in AD, T2D, or both diseases.
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Affiliation(s)
- Maryam Aftabizadeh
- Division of Peptide Biochemistry, Technische Universität München, Emil-Erlenmeyer-Forum 5, D-85354 Freising, Germany
- Cancer Immunotherapeutics and Tumor Immunology, City of Hope Medical Center Duarte, 1500 East Duarte Road, Duarte, California 91010, United States
| | | | - Erika Andreetto
- Division of Peptide Biochemistry, Technische Universität München, Emil-Erlenmeyer-Forum 5, D-85354 Freising, Germany
| | - Omar El Bounkari
- Chair of Vascular Biology, Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-University of Munich, 81377 Munich, Germany
| | - Markus Kipp
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany
| | | | - Eicke Latz
- Institute of Innate Immunity, University of Bonn, Biomedical Center, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany
- Division of Infectious Diseases & Immunology, University of Massachusetts Medical School, 364 Plantation St., Worcester, Massachusetts 01605, United States
| | - Jürgen Bernhagen
- Chair of Vascular Biology, Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-University of Munich, 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Aphrodite Kapurniotu
- Division of Peptide Biochemistry, Technische Universität München, Emil-Erlenmeyer-Forum 5, D-85354 Freising, Germany
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Musa H, Hendrikse ER, Brimble MA, Garelja ML, Watkins HA, Harris PWR, Hay DL. Pharmacological Characterization and Investigation of N-Terminal Loop Amino Acids of Adrenomedullin 2 That Are Important for Receptor Activation. Biochemistry 2019; 58:3468-3474. [PMID: 31328503 DOI: 10.1021/acs.biochem.9b00571] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Adrenomedullin 2 (AM2) is a peptide hormone with potent effects in the cardiovascular system. The N-terminal disulfide loop of AM2 is thought to be important for interacting with its receptors to initiate a signaling response. However, the relative contribution of each amino acid within this region is currently unknown. Thus, the region was investigated using an alanine scanning approach. Two AM2 peptides (AM2-47 and AM2-40) were directly compared at the CGRP, AM1, and AM2 receptors in transfected Cos7 cells and found to have equivalent activity. Analogues of AM2-40 were then synthesized, substituting each individual amino acid within the disulfide loop with alanine. The ability of these analogues to stimulate a cAMP response was evaluated at the CGRP, AM1, and AM2 receptors. AM2-40 L12A and T14A were less able to elicit cAMP responses through all tested receptors. In contrast, AM2-40 G13A was slightly more potent than the unmodified peptide at all tested receptors. Thus, it appears that residues within the disulfide loop region play differential roles in the ability of AM2 to stimulate cAMP production. The data provide the first structure-function investigation of AM2 agonism.
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Affiliation(s)
- Hala Musa
- School of Biological Sciences , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand
| | - Erica R Hendrikse
- School of Biological Sciences , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand
| | - Margaret A Brimble
- School of Biological Sciences , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand.,School of Chemical Sciences , The University of Auckland , 23 Symonds Street , Auckland 1010 , New Zealand
| | - Michael L Garelja
- School of Biological Sciences , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand
| | - Harriet A Watkins
- School of Biological Sciences , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand
| | - Paul W R Harris
- School of Biological Sciences , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand.,School of Chemical Sciences , The University of Auckland , 23 Symonds Street , Auckland 1010 , New Zealand
| | - Debbie L Hay
- School of Biological Sciences , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery , The University of Auckland , 3A Symonds Street , Auckland 1010 , New Zealand
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Depre C, Antalik L, Starling A, Koren M, Eisele O, Lenz RA, Mikol DD. A Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Effect of Erenumab on Exercise Time During a Treadmill Test in Patients With Stable Angina. Headache 2019; 58:715-723. [PMID: 29878340 PMCID: PMC6001517 DOI: 10.1111/head.13316] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 03/07/2018] [Accepted: 03/09/2018] [Indexed: 11/26/2022]
Abstract
Objective To determine the potential impact of erenumab, a human anti‐calcitonin gene‐related peptide (CGRP) receptor monoclonal antibody, on total exercise time (TET), time to exercise‐induced angina, and ST depression in a double‐blind, placebo‐controlled study in patients with stable angina due to documented coronary artery disease. Background The relative importance of the CGRP receptor pathway during myocardial ischemia has not been established. Methods An exercise treadmill test was conducted following a single IV infusion of erenumab 140 mg or placebo. The primary endpoint was the change from baseline in exercise duration as measured by TET with a noninferiority margin of −90 seconds. Safety follow‐up visits occurred through week 12. Eighty‐eight participants were included in the analysis. Results LS mean (SE) change in TET was −2.9 [14.8] seconds in the erenumab group and 8.1 [14.4] seconds in placebo; adjusted mean (90% CI) treatment difference was −11.0 (–44.9, 22.9) seconds. The CI lower bound (–44.9 sec) did not reach pre‐defined non‐inferiority margin of −90 seconds, demonstrating that TET change from baseline in the erenumab group was non‐inferior to placebo. There was no difference in time to exercise‐induced angina in erenumab and placebo groups (median [90% CI] time of 500 [420, 540] vs 508 [405, 572] seconds; hazard ratio [90% CI]: 1.11 [0.73, 1.69], P = .69) or time to onset of ≥1 mm ST‐segment depression (median [90% CI] time of 407 [380, 443] vs 420 [409,480] seconds; hazard ratio [95% CI]: 1.14 [0.76, 1.69], P = .59). Adverse events were reported by 27% and 32% of patients in erenumab and placebo groups. Conclusions Erenumab did not adversely affect exercise time in a high cardiovascular risk population of patients, supporting that inhibition of the canonical CGRP receptor does not worsen myocardial ischemia.
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Affiliation(s)
| | - Lubomir Antalik
- Cardiological Department, Regional Hospital, Slovakia (L. Antalik)
| | | | - Michael Koren
- Jacksonville Center for Clinical Research, Jacksonville, FL, USA
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Sah SK, Samuel VP, Dahiya S, Singh Y, Gilhotra RM, Gupta G, Mishra A, Sharma RK, Kumar GS, SreeHarsha N, Chellappan DK, Dua K. A contemporary biological pathway of islet amyloid polypeptide for the management of diabetic dementia. Chem Biol Interact 2019; 306:117-122. [PMID: 31004596 DOI: 10.1016/j.cbi.2019.04.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/11/2019] [Accepted: 04/17/2019] [Indexed: 01/07/2023]
Abstract
Major challenges of dealing elder patients with diabetes mellitus (DM) are the individualization of consideration in persons with various comorbid types of conditions. In spite of the fact that microvascular and macrovascular problems associated with DM are well documented, there is only a few numbers of reports viewing different conditions, for example, cognitive dysfunction. Cognitive dysfunction is of specific significance due to its effect on self-care and quality of life. All in all, the etiology of cognitive dysfunction in the maturing populace is probably going to be the grouping of ischemic and degenerative pathology. It is likewise trusted that Hyperglycemia is engaged with the system of DM-related cognitive dysfunction. At present, it isn't certain in the case of enhancing glycemic control or utilizing therapeutic agents can enhance the risk of cognitive decay. Amylin was later characterized as an amyloidogenic peptide, confined from a beta cell tumor and called islet amyloid polypeptide (IAPP), and after that, amylin. Conversely, we investigate the beneficial role and hypothesizing the mechanism of amylin related expanding the level and activation of CGRP receptor to enhance the cognition declination amid diabetic dementia.
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Affiliation(s)
| | - Vijaya Paul Samuel
- Department of Anatomy, RAK College of Medicine, RAK Medical and Health Sciences, University, Ras Al Khaimah, United Arab Emirates
| | - Sunita Dahiya
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico, USA
| | - Yogendar Singh
- Department of Pharmaceutical Sciences, Mahatma Gandhi College of Pharmaceutical Sciences, Sitapura, Jaipur, India
| | - Ritu M Gilhotra
- School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India
| | - Gaurav Gupta
- School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India.
| | - Anurag Mishra
- School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India
| | - Rakesh Kumar Sharma
- School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India
| | | | - Nagaraja SreeHarsha
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa, Saudi Arabia
| | - Dinesh Kumar Chellappan
- Department of Life Sciences, School of Pharmacy, International Medical University, Bukit Jalil, Kuala Lumpur, 57000, Malaysia
| | - Kamal Dua
- Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney (UTS), Ultimo, NSW 2007, Australia; Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute (HMRI) & School of Biomedical Sciences and Pharmacy, The University of Newcastle (UoN), Callaghan, NSW 2308, Australia.
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Akter R, Bower RL, Abedini A, Schmidt AM, Hay DL, Raleigh DP. Amyloidogenicity, Cytotoxicity, and Receptor Activity of Bovine Amylin: Implications for Xenobiotic Transplantation and the Design of Nontoxic Amylin Variants. ACS Chem Biol 2018; 13:2747-2757. [PMID: 30086232 DOI: 10.1021/acschembio.8b00690] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Islet amyloid formation contributes to β-cell death and dysfunction in type-2 diabetes and to the failure of islet transplants. Amylin (islet amyloid polypeptide, IAPP), a normally soluble 37 residue polypeptide hormone produced in the pancreatic β-cells, is responsible for amyloid formation in type-2 diabetes and is deficient in type-1 diabetes. Amylin normally plays an adaptive role in metabolism, and the development of nontoxic, non-amyloidogenic, bioactive variants of human amylin are of interest for use as adjuncts to insulin therapy. Naturally occurring non-amyloidogenic variants are of interest for xenobiotic transplantation and because they can provide clues toward understanding the amyloidogenicity of human amylin. The sequence of amylin is well-conserved among species, but sequence differences strongly correlate with in vitro amyloidogenicity and with islet amyloid formation in vivo. Bovine amylin differs from the human peptide at 10 positions and is one of the most divergent among known amylin sequences. We show that bovine amylin oligomerizes but is not toxic to cultured β-cells and that it is considerably less amyloidogenic than the human polypeptide and is only a low-potency agonist at human amylin-responsive receptors. The bovine sequence contains several nonconservative substitutions relative to human amylin, including His to Pro, Ser to Pro, and Asn to Lys replacements. The effect of these substitutions is analyzed in the context of wild-type human amylin; the results provide insight into their role in receptor activation, the mode of assembly of human amylin, and the design of soluble amylin analogues.
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Affiliation(s)
- Rehana Akter
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Rebekah L. Bower
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 1142, New Zealand
| | - Andisheh Abedini
- Diabetes Research Program, NYU School of Medicine, 522 First Avenue, New York, New York 10016, United States
| | - Ann Marie Schmidt
- Diabetes Research Program, NYU School of Medicine, 522 First Avenue, New York, New York 10016, United States
| | - Debbie L. Hay
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 1142, New Zealand
| | - Daniel P. Raleigh
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom
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Mietlicki-Baase EG. Amylin in Alzheimer's disease: Pathological peptide or potential treatment? Neuropharmacology 2018; 136:287-297. [PMID: 29233636 PMCID: PMC5994175 DOI: 10.1016/j.neuropharm.2017.12.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/06/2017] [Accepted: 12/07/2017] [Indexed: 12/19/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease for which we currently lack effective treatments or a cure. The pancreatic peptide hormone amylin has recently garnered interest as a potential pharmacological target for the treatment of AD. A number of studies have demonstrated that amylin and amylin analogs like the FDA-approved diabetes drug pramlintide can reduce amyloid burden in the brain and improve cognitive symptoms of AD. However, other data suggest that amylin may have pathological effects in AD due to its propensity to misfold and aggregate under certain conditions. Here, the literature supporting a beneficial versus harmful role of amylin in AD is reviewed. Additionally, several critical gaps in the literature are discussed, such as our limited understanding of the amylin system during aging and in disease states, as well as complexities of amylin receptor signaling and of changing pathophysiology during AD progression that might underlie the seemingly conflicting or contradictory results in the amylin/AD literature. This article is part of the Special Issue entitled 'Metabolic Impairment as Risk Factors for Neurodegenerative Disorders.'
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Affiliation(s)
- Elizabeth G Mietlicki-Baase
- Department of Exercise and Nutrition Sciences, School of Public Health and Health Professions, State University of New York at Buffalo, Buffalo, NY 14214, USA.
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Abstract
PURPOSE OF REVIEW Obesity is a global health crisis with detrimental effects on all organ systems leading to worsening disease state and rising costs of care. Persons with obesity failing lifestyle therapies need to be escalated to appropriate pharmacological treatment modalities, medical devices, and/or bariatric surgery if criteria are met and more aggressive intervention is needed. The progression of severe obesity in the patient population coupled with related co-morbidities necessitates the development of novel therapies for the treatment of obesity. This development is preceded by increased understanding of the underpinnings of energy regulation and neurohormonal pathways involved in energy homeostasis. RECENT FINDINGS Though there are approved anti-obesity drugs available in the USA, newer drugs are now in the pipeline for development given the urgent need. This review focuses on anti-obesity drugs in the pipeline including centrally acting agents (setmelanotide, neuropeptide Y antagonist [velneperit], zonisamide-bupropion [Empatic], cannabinoid type-1 receptor blockers), gut hormones and incretin targets (new glucagon-like-peptide-1 [GLP-1] analogues [semaglutide and oral equivalents], amylin mimetics [davalintide, dual amylin and calcitonin receptor agonists], dual action GLP-1/glucagon receptor agonists [oxyntomodulin], triple agonists [tri-agonist 1706], peptide YY, leptin analogues [combination pramlintide-metreleptin]), and other novel targets (methionine aminopeptidase 2 inhibitor [beloranib], lipase inhibitor [cetilistat], triple monoamine reuptake inhibitor [tesofensine], fibroblast growth factor 21), including anti-obesity vaccines (ghrelin, somatostatin, adenovirus36). With these new drugs in development, anti-obesity therapeutics have potential to vastly expand allowing better treatment options and personalized approach to obesity care.
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Affiliation(s)
- Gitanjali Srivastava
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition and Weight Management, Boston University School of Medicine, 720 Harrison Avenue, 8th Floor, Suite 801, Boston, MA, 02118, USA
| | - Caroline Apovian
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition and Weight Management, Boston University School of Medicine, 720 Harrison Avenue, 8th Floor, Suite 801, Boston, MA, 02118, USA.
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Hendrikse ER, Bower RL, Hay DL, Walker CS. Molecular studies of CGRP and the CGRP family of peptides in the central nervous system. Cephalalgia 2018; 39:403-419. [PMID: 29566540 DOI: 10.1177/0333102418765787] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Calcitonin gene-related peptide is an important target for migraine and other painful neurovascular conditions. Understanding the normal biological functions of calcitonin gene-related peptide is critical to understand the mechanisms of calcitonin gene-related peptide-blocking therapies as well as engineering improvements to these medications. Calcitonin gene-related peptide is closely related to other peptides in the calcitonin gene-related peptide family of peptides, including amylin. Relatedness in peptide sequence and in receptor biology makes it difficult to tease apart the contributions that each peptide and receptor makes to physiological processes and to disorders. SUMMARY The focus of this review is the expression of calcitonin gene-related peptide, related peptides and their receptors in the central nervous system. Calcitonin gene-related peptide is expressed throughout the nervous system, whereas amylin and adrenomedullin have only limited expression at discrete sites in the brain. The components of two receptors that respond to calcitonin gene-related peptide, the calcitonin gene-related peptide receptor (calcitonin receptor-like receptor with receptor activity-modifying protein 1) and the AMY1 receptor (calcitonin receptor with receptor activity-modifying protein 1), are expressed throughout the nervous system. Understanding expression of the peptides and their receptors lays the foundation for more deeply understanding their physiology, pathophysiology and therapeutic use.
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Affiliation(s)
- Erica R Hendrikse
- 1 School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Rebekah L Bower
- 1 School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Debbie L Hay
- 1 School of Biological Sciences, University of Auckland, Auckland, New Zealand.,2 Centre for Brain Research, University of Auckland, Auckland, New Zealand
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Abstract
Amylin is a 37 amino acid peptide hormone that is closely related to calcitonin gene-related peptide (CGRP). Amylin and CGRP share a receptor and are reported to have several similar biological actions. Given the important role of CGRP in migraine and intense efforts to develop drugs against this target, it is important to consider potential areas of overlap between the amylin and CGRP systems. This short review provides a brief introduction to amylin biology, the use of an amylin analog to treat diabetes, and consideration of whether amylin could have any role in headache disorders. Finally, this review informs readers about the AMY1 (amylin subtype 1) receptor, which is a dual receptor for amylin and CGRP and potentially plays a role in the bioactivity of both of these peptides.
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Affiliation(s)
- Debbie L Hay
- School of Biological Sciences, The University of Auckland, 3A Symonds Street, Auckland 1142, New Zealand
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36
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Abstract
Calcitonin gene-related peptide (CGRP) has many reported pharmacological actions. Can a single receptor explain all of these? This chapter outlines the molecular nature of reported CGRP binding proteins and their pharmacology. Consideration of whether CGRP has only one or has more receptors is important because of the key role that this peptide plays in migraine. It is widely thought that the calcitonin receptor-like receptor together with receptor activity-modifying protein 1 (RAMP1) is the only relevant receptor for CGRP. However, some closely related receptors also have high affinity for CGRP and it is still plausible that these play a role in CGRP biology, and in migraine. The calcitonin receptor/RAMP1 complex, which is currently called the AMY1 receptor, seems to be the most likely candidate but more investigation is needed to determine its role.
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Hay DL, Garelja ML, Poyner DR, Walker CS. Update on the pharmacology of calcitonin/CGRP family of peptides: IUPHAR Review 25. Br J Pharmacol 2017; 175:3-17. [PMID: 29059473 DOI: 10.1111/bph.14075] [Citation(s) in RCA: 236] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/27/2017] [Accepted: 09/28/2017] [Indexed: 12/19/2022] Open
Abstract
The calcitonin/CGRP family of peptides includes calcitonin, α and β CGRP, amylin, adrenomedullin (AM) and adrenomedullin 2/intermedin (AM2/IMD). Their receptors consist of one of two GPCRs, the calcitonin receptor (CTR) or the calcitonin receptor-like receptor (CLR). Further diversity arises from heterodimerization of these GPCRs with one of three receptor activity-modifying proteins (RAMPs). This gives the CGRP receptor (CLR/RAMP1), the AM1 and AM2 receptors (CLR/RAMP2 or RAMP3) and the AMY1, AMY2 and AMY3 receptors (CTR/RAMPs1-3 complexes, respectively). Apart from the CGRP receptor, there are only peptide antagonists widely available for these receptors, and these have limited selectivity, thus defining the function of each receptor in vivo remains challenging. Further challenges arise from the probable co-expression of CTR with the CTR/RAMP complexes and species-dependent splice variants of the CTR (CT(a) and CT(b) ). Furthermore, the AMY1(a) receptor is activated equally well by both amylin and CGRP, and the preferred receptor for AM2/IMD has been unclear. However, there are clear therapeutic rationales for developing agents against the various receptors for these peptides. For example, many agents targeting the CGRP system are in clinical trials, and pramlintide, an amylin analogue, is an approved therapy for insulin-requiring diabetes. This review provides an update on the pharmacology of the calcitonin family of peptides by members of the corresponding subcommittee of the International Union of Basic and Clinical Pharmacology and colleagues.
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Affiliation(s)
- Debbie L Hay
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Michael L Garelja
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - David R Poyner
- School of Life and Health Sciences, Aston University, Birmingham, UK
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Boyle CN, Lutz TA, Le Foll C. Amylin - Its role in the homeostatic and hedonic control of eating and recent developments of amylin analogs to treat obesity. Mol Metab 2017; 8:203-210. [PMID: 29203236 PMCID: PMC5985014 DOI: 10.1016/j.molmet.2017.11.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 11/13/2017] [Accepted: 11/17/2017] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Amylin is a pancreatic β-cell hormone that produces effects in several different organ systems. One of its best-characterized effects is the reduction in eating and body weight seen in preclinical and clinical studies. Amylin activates specific receptors, a portion of which it shares with calcitonin gene-related peptide (CGRP). Amylin's role in the control of energy metabolism relates to its satiating effect, but recent data indicate that amylin may also affect hedonic aspects in the control of eating, including a reduction of the rewarding value of food. Recently, several amylin-based peptides have been characterized. Pramlintide (Symlin®) is currently the only one being used clinically to treat type 1 and type 2 diabetes. However other amylin analogs with improved pharmacokinetic properties are being considered as anti-obesity treatment strategies. Several other studies in obesity have shown that amylin agonists could also be useful for weight loss, especially in combination with other agents. SCOPE OF REVIEW This review will briefly summarize amylin physiology and pharmacology and then focus on amylin's role in food reward and the effects of amylin analogs in pre-clinical testing for anti-obesity drugs. CONCLUSION We propose here that the effects of amylin may be homeostatic and hedonic in nature.
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Affiliation(s)
- Christina Neuner Boyle
- Institute of Veterinary Physiology and Zurich Centre for Integrative Human Physiology, University of Zurich, Switzerland
| | - Thomas Alexander Lutz
- Institute of Veterinary Physiology and Zurich Centre for Integrative Human Physiology, University of Zurich, Switzerland.
| | - Christelle Le Foll
- Institute of Veterinary Physiology and Zurich Centre for Integrative Human Physiology, University of Zurich, Switzerland
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Woolley MJ, Reynolds CA, Simms J, Walker CS, Mobarec JC, Garelja ML, Conner AC, Poyner DR, Hay DL. Receptor activity-modifying protein dependent and independent activation mechanisms in the coupling of calcitonin gene-related peptide and adrenomedullin receptors to Gs. Biochem Pharmacol 2017; 142:96-110. [PMID: 28705698 PMCID: PMC5609567 DOI: 10.1016/j.bcp.2017.07.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 07/06/2017] [Indexed: 12/23/2022]
Abstract
Calcitonin gene-related peptide (CGRP) or adrenomedullin (AM) receptors are heteromers of the calcitonin receptor-like receptor (CLR), a class B G protein-coupled receptor, and one of three receptor activity-modifying proteins (RAMPs). How CGRP and AM activate CLR and how this process is modulated by RAMPs is unclear. We have defined how CGRP and AM induce Gs-coupling in CLR-RAMP heteromers by measuring the effect of targeted mutagenesis in the CLR transmembrane domain on cAMP production, modeling the active state conformations of CGRP and AM receptors in complex with the Gs C-terminus and conducting molecular dynamics simulations in an explicitly hydrated lipidic bilayer. The largest effects on receptor signaling were seen with H295A5.40b, I298A5.43b, L302A5.47b, N305A5.50b, L345A6.49b and E348A6.52b, F349A6.53b and H374A7.47b (class B numbering in superscript). Many of these residues are likely to form part of a group in close proximity to the peptide binding site and link to a network of hydrophilic and hydrophobic residues, which undergo rearrangements to facilitate Gs binding. Residues closer to the extracellular loops displayed more pronounced RAMP or ligand-dependent effects. Mutation of H3747.47b to alanine increased AM potency 100-fold in the CGRP receptor. The molecular dynamics simulation showed that TM5 and TM6 pivoted around TM3. The data suggest that hydrophobic interactions are more important for CLR activation than other class B GPCRs, providing new insights into the mechanisms of activation of this class of receptor. Furthermore the data may aid in the understanding of how RAMPs modulate the signaling of other class B GPCRs.
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Affiliation(s)
- Michael J Woolley
- Institute of Clinical Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Christopher A Reynolds
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - John Simms
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, UK
| | | | - Juan Carlos Mobarec
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Michael L Garelja
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Alex C Conner
- Institute of Clinical Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - David R Poyner
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, UK.
| | - Debbie L Hay
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.
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40
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Whiting L, McCutcheon JE, Boyle CN, Roitman MF, Lutz TA. The area postrema (AP) and the parabrachial nucleus (PBN) are important sites for salmon calcitonin (sCT) to decrease evoked phasic dopamine release in the nucleus accumbens (NAc). Physiol Behav 2017; 176:9-16. [PMID: 28342771 DOI: 10.1016/j.physbeh.2017.03.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 03/16/2017] [Accepted: 03/17/2017] [Indexed: 12/26/2022]
Abstract
The pancreatic hormone amylin and its agonist salmon calcitonin (sCT) act via the area postrema (AP) and the lateral parabrachial nucleus (PBN) to reduce food intake. Investigations of amylin and sCT signaling in the ventral tegmental area (VTA) and nucleus accumbens (NAc) suggest that the eating inhibitory effect of amylin is, in part, mediated through the mesolimbic 'reward' pathway. Indeed, administration of the sCT directly to the VTA decreased phasic dopamine release (DA) in the NAc. However, it is not known if peripheral amylin modulates the mesolimbic system directly or whether this occurs via the AP and PBN. To determine whether and how peripheral amylin or sCT affect mesolimbic reward circuitry we utilized fast scan cyclic voltammetry under anesthesia to measure phasic DA release in the NAc evoked by electrical stimulation of the VTA in intact, AP lesioned and bilaterally PBN lesioned rats. Amylin (50μg/kg i.p.) did not change phasic DA responses compared to saline control rats. However, sCT (50μg/kg i.p.) decreased evoked DA release to VTA-stimulation over 1h compared to saline treated control rats. Further investigations determined that AP and bilateral PBN lesions abolished the ability of sCT to suppress evoked phasic DA responses to VTA-stimulation. These findings implicate the AP and the PBN as important sites for peripheral sCT to decrease evoked DA release in the NAc and suggest that these nuclei may influence hedonic and motivational processes to modulate food intake.
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Affiliation(s)
- Lynda Whiting
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - James E McCutcheon
- Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, England
| | - Christina N Boyle
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Mitchell F Roitman
- Department of Psychology, University of Illinois at Chicago, Chicago, IL, United States
| | - Thomas A Lutz
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Centre of Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
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41
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Hay DL, Walker CS. CGRP and its receptors. Headache 2017; 57:625-636. [PMID: 28233915 DOI: 10.1111/head.13064] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 01/26/2017] [Accepted: 02/01/2017] [Indexed: 02/01/2023]
Abstract
The calcitonin gene-related peptide (CGRP) neuropeptide system is an important but still evolving target for migraine. A fundamental consideration for all of the current drugs in clinical trials and for ongoing development in this area is the identity, expression pattern, and function of CGRP receptors because this knowledge informs safety and efficacy considerations. In recent years, only the calcitonin receptor-like receptor/receptor activity-modifying protein 1 (RAMP1) complex, known as the CGRP receptor, has generally been considered relevant. However, CGRP is capable of activating multiple receptors and could have more than one endogenous receptor. The recent identification of the CGRP-responsive calcitonin receptor/RAMP1 complex (AMY1 receptor - amylin subtype 1 receptor) in the trigeminovascular system warrants a deeper consideration of the molecular identity of CGRP receptor(s) involved in the pathophysiology, and thus potential treatment of migraine. This perspective considers some of the issues and implications.
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Affiliation(s)
- Debbie L Hay
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
| | - Christopher S Walker
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
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42
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Levin BE, Lutz TA. Amylin and Leptin: Co-Regulators of Energy Homeostasis and Neuronal Development. Trends Endocrinol Metab 2017; 28:153-164. [PMID: 27938937 DOI: 10.1016/j.tem.2016.11.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 11/03/2016] [Accepted: 11/07/2016] [Indexed: 12/18/2022]
Abstract
While the regulation of energy homeostasis by amylin is already well-characterized, emerging data suggest that amylin is also crucial for the development of neural pathways in the hypothalamus and caudal hindbrain (area postrema, AP; nucleus tractus solitarius, NTS). Exciting new findings demonstrate crucial amylin-leptin interactions in altering the activity of specific hypothalamic and AP neurons, and a role for amylin as a novel class of 'leptin sensitizers' which enhance leptin signaling in both leptin-sensitive and -resistant individuals, in part by stimulating IL-6 production by hypothalamic microglia. This review summarizes these findings and provides a hypothetical framework for future studies to elucidate the mechanisms by which amylin and leptin act individually and as co-conspirators to alter energy homeostasis and neuronal development.
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Affiliation(s)
- Barry E Levin
- Department of Neurology, Rutgers, New Jersey Medical School, Newark, NJ 07103, USA.
| | - Thomas A Lutz
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
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43
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Abegg K, Hermann A, Boyle CN, Bouret SG, Lutz TA, Riediger T. Involvement of Amylin and Leptin in the Development of Projections from the Area Postrema to the Nucleus of the Solitary Tract. Front Endocrinol (Lausanne) 2017; 8:324. [PMID: 29250032 PMCID: PMC5715394 DOI: 10.3389/fendo.2017.00324] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/02/2017] [Indexed: 01/15/2023] Open
Abstract
The area postrema (AP) and the nucleus of the solitary tract (NTS) are important hindbrain centers involved in the control of energy homeostasis. The AP mediates the anorectic action and the inhibitory effect on gastric emptying induced by the pancreatic hormone amylin. Amylin's target cells in the AP project to the NTS, an integrative relay center for enteroceptive signals. Perinatal hormonal and metabolic factors influence brain development. A postnatal surge of the adipocyte-derived hormone leptin represents a developmental signal for the maturation of projections between hypothalamic nuclei controlling energy balance. Amylin appears to promote neurogenesis in the AP in adult rats. Here, we examined whether amylin and leptin are required for the development of projections from the AP to the NTS in postnatal and adult mice by conducting neuronal tracing studies with DiI in amylin- (IAPP-/-) and leptin-deficient (ob/ob) mice. Compared to wild-type littermates, postnatal (P10) and adult (P60) IAPP-/- mice showed a significantly reduced density of AP-NTS projections. While AP projections were also reduced in postnatal (P14) ob/ob mice, AP-NTS fiber density did not differ between adult ob/ob and wild-type animals. Our findings suggest a crucial function of amylin for the maturation of neuronal brainstem pathways controlling energy balance and gastrointestinal function. The impaired postnatal development of neuronal AP-NTS projections in ob/ob mice appears to be compensated in this experimental model during later brain maturation. It remains to be elucidated whether an amylin- and leptin-dependent modulation in neuronal development translates into altered AP/NTS-mediated functions.
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Affiliation(s)
- Kathrin Abegg
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
- Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Andreas Hermann
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Christina N. Boyle
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Sebastien G. Bouret
- Developmental Neuroscience Program, The Saban Research Institute, University of Southern California, Los Angeles, California
- Inserm U1172, Jean-Pierre Aubert Research Center, University of Lille II, Lille
- Center for Endocrinology, Diabetes and Metabolism, Children’s Hospital Los Angeles, Los Angeles, California
| | - Thomas A. Lutz
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
- Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Thomas Riediger
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
- Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
- *Correspondence: Thomas Riediger,
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44
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Bhowmick DC, Singh S, Trikha S, Jeremic AM. The Molecular Physiopathogenesis of Islet Amyloidosis. Handb Exp Pharmacol 2017; 245:271-312. [PMID: 29043504 DOI: 10.1007/164_2017_62] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Human islet amyloid polypeptide or amylin (hA) is a 37-amino acid peptide hormone produced and co-secreted with insulin by pancreatic β-cells. Under physiological conditions, hA regulates a broad range of biological processes including insulin release and slowing of gastric emptying, thereby maintaining glucose homeostasis. However, under the pathological conditions associated with type 2 diabetes mellitus (T2DM), hA undergoes a conformational transition from soluble random coil monomers to alpha-helical oligomers and insoluble β-sheet amyloid fibrils or amyloid plaques. There is a positive correlation between hA oligomerization/aggregation, hA toxicity, and diabetes progression. Because the homeostatic balance between hA synthesis, release, and uptake is lost in diabetics and hA aggregation is a hallmark of T2DM, this chapter focuses on the biophysical and cell biology studies investigating molecular mechanisms of hA uptake, trafficking, and degradation in pancreatic cells and its relevance to h's toxicity. We will also discuss the regulatory role of endocytosis and proteolytic pathways in clearance of toxic hA species. Finally, we will discuss potential pharmacological approaches for specific targeting of hA trafficking pathways and toxicity in islet β-cells as potential new avenues toward treatments of T2DM patients.
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Affiliation(s)
| | - Sanghamitra Singh
- Department of Biological Sciences, The George Washington University, Washington, DC, 20052, USA
| | - Saurabh Trikha
- Department of Biological Sciences, The George Washington University, Washington, DC, 20052, USA
| | - Aleksandar M Jeremic
- Department of Biological Sciences, The George Washington University, Washington, DC, 20052, USA.
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45
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Lutz TA. Gut hormones such as amylin and GLP-1 in the control of eating and energy expenditure. INTERNATIONAL JOURNAL OF OBESITY SUPPLEMENTS 2016; 6:S15-S21. [PMID: 28685025 DOI: 10.1038/ijosup.2016.4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The control of meal size is the best studied aspect of the control of energy balance, and manipulation of this system constitutes a promising target to treat obesity. A major part of this control system is based on gastrointestinal hormones such as glucagon-like peptide-1 (GLP-1) or amylin, which are released in response to a meal and which limit the size of an ongoing meal. Both amylin and GLP-1 have also been shown to increase energy expenditure in experimental rodents, but mechanistically we know much less how this effect may be mediated, which brain sites may be involved, and what the physiological relevance of these findings may be. Most studies indicate that the effect of peripheral amylin is centrally mediated via the area postrema, but other brain areas, such as the ventral tegmental area, may also be involved. GLP-1's effect on eating seems to be mainly mediated by vagal afferents projecting to the caudal hindbrain. Chronic exposure to amylin, GLP-1 or their analogs decrease food intake and body weight gain. Next to the induction of satiation, amylin may also constitute an adiposity signal and in fact interact with the adiposity signal leptin. Amylin analogs are under clinical consideration for their effect to reduce food intake and body weight in humans, and similar to rodents, amylin analogs seem to be particularly active when combined with leptin analogs.
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Affiliation(s)
- T A Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich, Zurich, Switzerland.,Zurich Center of Integrative Human Physiology, University of Zurich, Zurich, Switzerland
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46
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Potes C, Pestana A, Pontes M, Caramelo A, Neto F. Amylin modulates the formalin-induced tonic pain behaviours in rats. Eur J Pain 2016; 20:1741-1752. [DOI: 10.1002/ejp.898] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2016] [Indexed: 12/12/2022]
Affiliation(s)
- C.S. Potes
- Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Departamento de Biologia Experimental; Faculdade de Medicina; Universidade do Porto; Porto Portugal
| | - A.C. Pestana
- Departamento de Biologia Experimental; Faculdade de Medicina; Universidade do Porto; Porto Portugal
| | - M. Pontes
- Departamento de Biologia Experimental; Faculdade de Medicina; Universidade do Porto; Porto Portugal
| | - A.S. Caramelo
- Departamento de Biologia Experimental; Faculdade de Medicina; Universidade do Porto; Porto Portugal
| | - F.L. Neto
- Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Departamento de Biologia Experimental; Faculdade de Medicina; Universidade do Porto; Porto Portugal
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47
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Khoshdel Z, Takhshid MA, Owji AA. Effects of intrathecal amylin on formalin-induced nociception and on cAMP accumulation in the rat embryonic spinal cells. Neuropeptides 2016; 57:95-100. [PMID: 26778650 DOI: 10.1016/j.npep.2015.12.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 12/23/2015] [Accepted: 12/26/2015] [Indexed: 11/17/2022]
Abstract
Amylin (AMY) is a member of calcitonin family of peptides. In this study, the effects of intrathecal (i.t) injection of AMY on the inflammatory pain and on the cAMP accumulation in the rat spinal cells were investigated. By using AMY receptor antagonists, we also studied the pharmacology of AMY receptors in the spinal cells. Formalin model of inflammatory pain was induced by intraplantar injection of formalin. AMY (0.06250-2500pmol/rat) was administrated i.t 15min before the injection of formalin. Antagonists were injected i.t 10min before the injection of AMY and/or morphine. AMY reduced formalin-induced pain in a dose dependent mode. This effect was inhibited by the potent AMY antagonist, AC187 but not CGRP8-37. rAMY8-37, most commonly reported as a weak AMY antagonist, showed to be equally or more potent than AC187 in antagonizing the above effects. The opioid antagonist, naloxone, had no significant effects on AMY antinociceptive effects. Primary dissociated cell culture was used to investigate the effect of AMY on cAMP production and to characterize AMY receptors in the spinal cells. AMY moderately increases cAMP accumulation in the spinal cells with an EC50 value of 74.62nM. This effect was not affected by CGRP8-37 but was inhibited by AC187 and rAMY8-37 with pA2 values of 7.94 and 7.87 respectively. In conclusion, effects of AMY in reducing formalin induced pain and on the cAMP accumulation by spinal cells are mediated through undefined receptors.
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Affiliation(s)
- Zahra Khoshdel
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Ali Takhshid
- Diagnostic Laboratory Sciences and Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - Ali Akbar Owji
- Research Center for Psychiatry and Behavioral Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
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48
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Bower RL, Hay DL. Amylin structure-function relationships and receptor pharmacology: implications for amylin mimetic drug development. Br J Pharmacol 2016; 173:1883-98. [PMID: 27061187 DOI: 10.1111/bph.13496] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/15/2016] [Accepted: 03/15/2016] [Indexed: 01/19/2023] Open
Abstract
Amylin is an important, but poorly understood, 37 amino acid glucoregulatory hormone with great potential to target metabolic diseases. A working example that the amylin system is one worth developing is the FDA-approved drug used in insulin-requiring diabetic patients, pramlintide. However, certain characteristics of pramlintide pharmacokinetics and formulation leave considerable room for further development of amylin-mimetic compounds. Given that amylin-mimetic drug design and development is an active area of research, surprisingly little is known about the structure/function relationships of amylin. This is largely due to the unfavourable aggregative and solubility properties of the native peptide sequence, which are further complicated by the composition of amylin receptors. These are complexes of the calcitonin receptor with receptor activity-modifying proteins. This review explores what is known of the structure-function relationships of amylin and provides insights that can be drawn from the closely related peptide, CGRP. We also describe how this information is aiding the development of more potent and stable amylin mimetics, including peptide hybrids.
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Affiliation(s)
- Rebekah L Bower
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - Debbie L Hay
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
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49
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Liberini CG, Boyle CN, Cifani C, Venniro M, Hope BT, Lutz TA. Amylin receptor components and the leptin receptor are co-expressed in single rat area postrema neurons. Eur J Neurosci 2016; 43:653-61. [PMID: 26750109 PMCID: PMC10704335 DOI: 10.1111/ejn.13163] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 12/17/2015] [Accepted: 12/22/2015] [Indexed: 12/16/2023]
Abstract
Amylin is a pancreatic β-cell hormone that acts as a satiating signal to inhibit food intake by binding to amylin receptors (AMYs) and activating a specific neuronal population in the area postrema (AP). AMYs are heterodimers that include a calcitonin receptor (CTR) subunit [CTR isoform a or b (CTRa or CTRb)] and a member of the receptor activity-modifying proteins (RAMPs). Here, we used single-cell quantitative polymerase chain reaction to assess co-expression of AMY subunits in AP neurons from rats that were injected with amylin or vehicle. Because amylin interacts synergistically with the adipokine leptin to reduce body weight, we also assessed the co-expression of AMY and the leptin receptor isoform b (LepRb) in amylin-activated AP neurons. Single cells were collected from Wistar rats and from transgenic Fos-GFP rats that express green fluorescent protein (GFP) under the control of the Fos promoter. We found that the mRNAs of CTRa, RAMP1, RAMP2 and RAMP3 were all co-expressed in single AP neurons. Moreover, most of the CTRa+ cells co-expressed more than one of the RAMPs. Amylin down-regulated RAMP1 and RAMP3 but not CTR mRNAs in AMY+ neurons, suggesting a possible negative feedback mechanism of amylin at its own primary receptors. Interestingly, amylin up-regulated RAMP2 mRNA. We also found that a high percentage of single cells that co-expressed all components of a functional AMY expressed LepRb mRNA. Thus, single AP cells expressed both AMY and LepRb, which formed a population of first-order neurons that presumably can be directly activated by amylin and, at least in part, also by leptin.
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Affiliation(s)
- Claudia G. Liberini
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich (UZH), Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
- Zurich Centre for Clinical Studies, Vetsuisse Faculty University of Zurich, Zurich, Switzerland
| | - Christina Neuner Boyle
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich (UZH), Zurich, Switzerland
| | - Carlo Cifani
- School of Pharmacy, Pharmacology Unit, University of Camerino, Italy
- Intramural Research Program, National Institutes of Health/National Institute on Drug Abuse, Baltimore, Maryland 21224
| | - Marco Venniro
- Intramural Research Program, National Institutes of Health/National Institute on Drug Abuse, Baltimore, Maryland 21224
| | - Bruce T. Hope
- Intramural Research Program, National Institutes of Health/National Institute on Drug Abuse, Baltimore, Maryland 21224
| | - Thomas A. Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich (UZH), Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
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50
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Dunn-Meynell AA, Le Foll C, Johnson MD, Lutz TA, Hayes MR, Levin BE. Endogenous VMH amylin signaling is required for full leptin signaling and protection from diet-induced obesity. Am J Physiol Regul Integr Comp Physiol 2016; 310:R355-65. [PMID: 26676252 PMCID: PMC4868368 DOI: 10.1152/ajpregu.00462.2015] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 12/10/2015] [Indexed: 12/29/2022]
Abstract
Amylin enhances arcuate (ARC) and ventromedial (VMN) hypothalamic nuclei leptin signaling and synergistically reduces food intake and body weight in selectively bred diet-induced obese (DIO) rats. Since DIO (125)I-amylin dorsomedial nucleus-dorsomedial VMN binding was reduced, we postulated that this contributed to DIO ventromedial hypothalamus (VMH) leptin resistance, and that impairing VMH (ARC + VMN) calcitonin receptor (CTR)-mediated signaling by injecting adeno-associated virus (AAV) expressing a short hairpin portion of the CTR mRNA would predispose diet-resistant (DR) rats to obesity on high-fat (45%) diet (HFD). Depleting VMH CTR by 80-90% in 4-wk-old male DR rats reduced their ARC and VMN (125)I-labeled leptin binding by 57 and 51%, respectively, and VMN leptin-induced phospho-signal transducer and activator of transcription 3-positive neurons by 59% vs. AAV control rats. After 6 wk on chow, VMH CTR-depleted DR rats ate and gained the equivalent amount of food and weight but had 18% heavier fat pads (relative to carcass weight), 144% higher leptin levels, and were insulin resistant compared with control AAV DR rats. After 6 wk more on HFD, VMH CTR-depleted DR rats ate the same amount but gained 28% more weight, had 60% more carcass fat, 254% higher leptin levels, and 132% higher insulin areas under the curve during an oral glucose tolerance test than control DR rats. Therefore, impairing endogenous VMH CTR-mediated signaling reduced leptin signaling and caused DR rats to become more obese and insulin resistant, both on chow and HFD. These results suggest that endogenous VMH amylin signaling is required for full leptin signaling and protection from HFD-induced obesity.
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Affiliation(s)
| | - Christelle Le Foll
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Miranda D Johnson
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Thomas A Lutz
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Matthew R Hayes
- Translational Neuroscience Program, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and
| | - Barry E Levin
- Neurology Service, Veterans Administration Medical Center, East Orange, New Jersey; Department of Neurology, Rutgers, New Jersey Medical School, Newark, New Jersey
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