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van der Valk ES, Kleinendorst L, Delhanty PJD, van der Voorn B, Visser JA, van Haelst MM, de Graaff LCG, Huisman M, White A, Ito S, Wakamatsu K, de Rijke YB, van den Akker ELT, Iyer AM, van Rossum EFC. Obesity and Hyperphagia With Increased Defective ACTH: A Novel POMC Variant. J Clin Endocrinol Metab 2022; 107:e3699-e3704. [PMID: 35737586 PMCID: PMC9797039 DOI: 10.1210/clinem/dgac342] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Patients with pro-opiomelanocortin (POMC) defects generally present with early-onset obesity, hyperphagia, hypopigmentation and adrenocorticotropin (ACTH) deficiency. Rodent models suggest that adequate cleavage of ACTH to α-melanocortin-stimulating hormone (α-MSH) and desacetyl-α-melanocortin-stimulating hormone (d-α-MSH) by prohormone convertase 2 at the KKRR region is required for regulating food intake and energy balance. METHODS We present 2 sisters with a novel POMC gene variant, leading to an ACTH defect at the prohormone convertase 2 cleavage site, and performed functional studies of this variant. RESULTS The patients had obesity, hyperphagia and hypocortisolism, with markerly raised levels of ACTH but unaffected pigmentation. Their ACTH has reduced potency to stimulate the melanocortin (MC) 2 receptor, explaining their hypocortisolism. CONCLUSION The hyperphagia and obesity support evidence that adequate cleavage of ACTH to α-MSH and d-α-MSH is also required in humans for feeding control.
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Affiliation(s)
- Eline S van der Valk
- Obesity Centre CGG, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
- Department of Internal Medicine, Division of Endocrinology, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
| | | | | | - Bibian van der Voorn
- Obesity Centre CGG, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
- Department of Internal Medicine, Division of Endocrinology, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus University Medical Center, 3000 CA Rotterdam, the Netherlands
| | - Jenny A Visser
- Obesity Centre CGG, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
- Department of Internal Medicine, Division of Endocrinology, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
| | - M M van Haelst
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, 1100 DD Amsterdam, the Netherlands
| | - Laura C G de Graaff
- Department of Internal Medicine, Division of Endocrinology, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
| | - Martin Huisman
- Department of Internal Medicine, Division of Endocrinology, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
| | - Anne White
- Divison of Diabetes, Endocrinology & Gastroenterology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Shosuke Ito
- Institute for Melanin Chemistry, Fujita Health University, Toyoake, 470-1192, Japan
| | - Kazumasa Wakamatsu
- Institute for Melanin Chemistry, Fujita Health University, Toyoake, 470-1192, Japan
| | - Yolanda B de Rijke
- Department of Clinical Chemistry, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
| | - Erica L T van den Akker
- Obesity Centre CGG, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus University Medical Center, 3000 CA Rotterdam, the Netherlands
| | - Anand M Iyer
- Obesity Centre CGG, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
- Department of Internal Medicine, Division of Endocrinology, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, the Netherlands
| | - Elisabeth F C van Rossum
- Correspondence: Elisabeth F. C. van Rossum, MD, PhD, Obesity Center CGG (Centrum Gezond Gewicht), Erasmus MC, University Medical Center Rotterdam, the Netherlands, Rm Rg-5. P. O. Box 2400, 3000 CA Rotterdam, the Netherlands.
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Kobayashi Y. New perspectives on GPCRs: GPCR heterodimer formation (melanocortin receptor) and GPCR on primary cilia (melanin concentrating hormone receptor). Gen Comp Endocrinol 2020; 293:113474. [PMID: 32240710 DOI: 10.1016/j.ygcen.2020.113474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 03/18/2020] [Accepted: 03/28/2020] [Indexed: 11/13/2022]
Abstract
GPCRs are the largest family of receptors accounting for about 30% of the current drug targets. However, it is difficult to fully elucidate the mechanisms regulating intracellular GPCR signal regulation. It is thus important to consider and investigate GPCRs with respect to endogenous situations. Our group has been investigating GPCRs involved in body color (teleost and amphibian) and eating (vertebrate). Here, I review two independent GPCR systems (heterodimer formation and primary ciliated GPCR) that can be breakthroughs in GPCR research. In teleosts, MCRs form heterodimers, which significantly reduce their affinity for acetylated ligands. In mammals, MCHR1 is localized in the ciliary membrane and shortens the length of the primary cilia through a unique signal from the ciliary membrane. Considering these two new GPCR concepts is expected to advance the overall view of the GPCR system.
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Affiliation(s)
- Yuki Kobayashi
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan.
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Harno E, Gali Ramamoorthy T, Coll AP, White A. POMC: The Physiological Power of Hormone Processing. Physiol Rev 2019; 98:2381-2430. [PMID: 30156493 DOI: 10.1152/physrev.00024.2017] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Pro-opiomelanocortin (POMC) is the archetypal polypeptide precursor of hormones and neuropeptides. In this review, we examine the variability in the individual peptides produced in different tissues and the impact of the simultaneous presence of their precursors or fragments. We also discuss the problems inherent in accurately measuring which of the precursors and their derived peptides are present in biological samples. We address how not being able to measure all the combinations of precursors and fragments quantitatively has affected our understanding of the pathophysiology associated with POMC processing. To understand how different ratios of peptides arise, we describe the role of the pro-hormone convertases (PCs) and their tissue specificities and consider the cellular processing pathways which enable regulated secretion of different peptides that play crucial roles in integrating a range of vital physiological functions. In the pituitary, correct processing of POMC peptides is essential to maintain the hypothalamic-pituitary-adrenal axis, and this processing can be disrupted in POMC-expressing tumors. In hypothalamic neurons expressing POMC, abnormalities in processing critically impact on the regulation of appetite, energy homeostasis, and body composition. More work is needed to understand whether expression of the POMC gene in a tissue equates to release of bioactive peptides. We suggest that this comprehensive view of POMC processing, with a focus on gaining a better understanding of the combination of peptides produced and their relative bioactivity, is a necessity for all involved in studying this fascinating physiological regulatory phenomenon.
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Affiliation(s)
- Erika Harno
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
| | - Thanuja Gali Ramamoorthy
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
| | - Anthony P Coll
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
| | - Anne White
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
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4
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Mountjoy KG, Caron A, Hubbard K, Shome A, Grey AC, Sun B, Bould S, Middleditch M, Pontré B, McGregor A, Harris PWR, Kowalczyk R, Brimble MA, Botha R, Tan KML, Piper SJ, Buchanan C, Lee S, Coll AP, Elmquist JK. Desacetyl-α-melanocyte stimulating hormone and α-melanocyte stimulating hormone are required to regulate energy balance. Mol Metab 2017; 9:207-216. [PMID: 29226825 PMCID: PMC5869732 DOI: 10.1016/j.molmet.2017.11.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/08/2017] [Accepted: 11/14/2017] [Indexed: 01/15/2023] Open
Abstract
Objective Regulation of energy balance depends on pro-opiomelanocortin (POMC)-derived peptides and melanocortin-4 receptor (MC4R). Alpha-melanocyte stimulating hormone (α-MSH) is the predicted natural POMC-derived peptide that regulates energy balance. Desacetyl-α-MSH, the precursor for α-MSH, is present in brain and blood. Desacetyl-α-MSH is considered to be unimportant for regulating energy balance despite being more potent (compared with α-MSH) at activating the appetite-regulating MC4R in vitro. Thus, the physiological role for desacetyl-α-MSH is still unclear. Methods We created a novel mouse model to determine whether desacetyl-α-MSH plays a role in regulating energy balance. We engineered a knock in targeted QKQR mutation in the POMC protein cleavage site that blocks the production of both desacetyl-α-MSH and α-MSH from adrenocorticotropin (ACTH1-39). Results The mutant ACTH1-39 (ACTHQKQR) functions similar to native ACTH1-39 (ACTHKKRR) at the melanocortin 2 receptor (MC2R) in vivo and MC4R in vitro. Male and female homozygous mutant ACTH1-39 (Pomctm1/tm1) mice develop the characteristic melanocortin obesity phenotype. Replacement of either desacetyl-α-MSH or α-MSH over 14 days into Pomctm1/tm1 mouse brain significantly reverses excess body weight and fat mass gained compared to wild type (WT) (Pomcwt/wt) mice. Here, we identify both desacetyl-α-MSH and α-MSH peptides as regulators of energy balance and highlight a previously unappreciated physiological role for desacetyl-α-MSH. Conclusions Based on these data we propose that there is potential to exploit the naturally occurring POMC-derived peptides to treat obesity but this relies on first understanding the specific function(s) for desacetyl-α-MSH and α-MSH. KKRR → QKQR mutation in the cleavage site of POMC prevents the production of desacetyl-α-MSH and α-MSH in mice. Male and female mutant mice develop characteristic melanocortin obesity. Central administration of α-MSH is more potent at reducing body weight in female mutant mice. Central administration of desacetyl-α-MSH and α-MSH are similarly potent at reducing body weight in male mutant mice.
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Affiliation(s)
- Kathleen G Mountjoy
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
| | - Alexandre Caron
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kristina Hubbard
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Avik Shome
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Angus C Grey
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Department of Anatomy and Medical Imaging, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Bo Sun
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Sarah Bould
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Martin Middleditch
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Beau Pontré
- Department of Anatomy and Medical Imaging, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Ailsa McGregor
- Department of Pharmacy, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Paul W R Harris
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Renata Kowalczyk
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Margaret A Brimble
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Rikus Botha
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Karen M L Tan
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge CB2 2QR, United Kingdom
| | - Sarah J Piper
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge CB2 2QR, United Kingdom
| | - Christina Buchanan
- Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Syann Lee
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Anthony P Coll
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge CB2 2QR, United Kingdom; University of Cambridge Metabolic Research Laboratories, MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Joel K Elmquist
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, USA
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Mao Z, Liu G, Chen JJ, Liu D, Xu MP, Zhao C, Yang HT, Yue YB. Serum α-melanocyte-stimulating hormone may act as a protective biomarker for non-traumatic osteonecrosis of the femoral head. Ann Clin Biochem 2017; 55:453-460. [PMID: 28990818 DOI: 10.1177/0004563217738802] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background The α-melanocyte-stimulating hormone (α-MSH), an endogenous neuropeptide derived from proopiomelanocortin (POMC), has been identified to suppress inflammation and prevent osteoblast damage. Objective The present study was aimed to investigate the role of serum α-MSH in non-traumatic osteonecrosis of the femoral head (ONFH). Methods Seventy-nine patients diagnosed with non-traumatic ONFH and 79 sex- and age-matched healthy controls were enrolled in the study. Serum α-MSH concentrations were examined with a double antibody radioimmunoassay. The radiographic progression of ONFH was assessed by X-ray plain film according to the FICAT grading system. The symptomatic severity was evaluated by visual analogue scale scores, Harris hip scores and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. The serum concentrations of protective marker adiponectin and bone necrosis inflammation factor IL-33 concentrations were also examined. The receiver operating characteristic (ROC) analysis curve was performed to explore the diagnostic value of α-MSH, adiponectin and IL-33 for radiographic progression. Results Serum α-MSH concentrations were significantly lower in ONFH patients than in healthy controls. The case group included 29 non-traumatic ONFH patients with FICAT grade I/II, 27 with grade III and 23 with grade IV. ONFH patients with grade I/II had significantly higher α-MSH concentrations in serum compared with those with FICAT grades III and IV. ONFH patients with FICAT grade III showed significantly elevated concentrations of α-MSH in serum compared with those with FICAT grade IV. Serum α-MSH concentrations were negatively associated with radiographic progression by FICAT grading system, and symptomatic severity defined by visual analogue scale scores, Harris hip scores and WOMAC scores. In addition, serum α-MSH concentrations were positively related to the expression of adiponectin and negatively associated with IL-33. ROC analysis curve demonstrated that α-MSH exhibited the equal value for the diagnosis of ONFH radiographic progression compared with IL-33. Conclusions Serum α-MSH may act as a protective biomarker for non-traumatic ONFH. Systematic application of α-MSH serving as an adjunctive therapy for treating non-traumatic ONFH deserves further investigation.
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Affiliation(s)
- Zheng Mao
- 1 Department of Rehabilitation Medicine, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China
| | - Gang Liu
- 1 Department of Rehabilitation Medicine, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China
| | - Jing-Jie Chen
- 1 Department of Rehabilitation Medicine, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China
| | - Dan Liu
- 1 Department of Rehabilitation Medicine, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China
| | - Min-Peng Xu
- 1 Department of Rehabilitation Medicine, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China
| | - Chang Zhao
- 2 Department of Orthopedics, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China
| | - Hai-Tao Yang
- 3 Department of Acupuncture, Guangdong Second Hospital of Traditional Chinese Medicine, Guangdong, China
| | - Yong-Bin Yue
- 4 Department of Orthopedics, Linyi People's Hospital, Linyi, Shandong Province, China.,5 Guangzhou University of Chinese Medicine, Guangzhou, China
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Kobayashi Y, Hamamoto A, Takahashi A, Saito Y. Dimerization of melanocortin receptor 1 (MC1R) and MC5R creates a ligand-dependent signal modulation: Potential participation in physiological color change in the flounder. Gen Comp Endocrinol 2016; 230-231:103-9. [PMID: 27080548 DOI: 10.1016/j.ygcen.2016.04.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 03/31/2016] [Accepted: 04/09/2016] [Indexed: 01/21/2023]
Abstract
Vertebrates produce α-melanocyte-stimulating hormone (α-MSH), which contains an N-terminal acetyl group, and desacetyl-α-MSH, which does not contain an N-terminal acetyl group. In teleosts and amphibians, α-MSH-related peptides stimulate pigment dispersion via melanocortin receptors 1-5 (MC1R-MC5R), which are members of the G-protein-coupled receptor (GPCR) family. We previously reported an interesting phenomenon associated with physiological color changes in the skin of a flatfish, barfin flounder (bf). Specifically, pigments in xanthophores expressing only the bfMC5R gene were dispersed by both α-MSH and desacetyl-α-MSH, whereas those in melanophores expressing both the bfMC1R and bfMC5R genes were dispersed by desacetyl-α-MSH, but not by α-MSH. In this study, we examined whether heterodimers of bfMC1R and bfMC5R can act as significant inhibitory receptors for the N-terminal acetylation of α-MSH in mammalian Chinese hamster ovary cells. Immunofluorescence analyses showed that bfMC1R and bfMC5R were localized together at the plasma membrane when expressed in the same cells. Indeed, after coexpression of Flag-bfMC1R and HA-bfMC5R, immunoprecipitation with anti-Flag antibodies resulted in the presence of anti-HA immunoreactivity in the precipitate, and vice versa. Importantly, cyclic AMP assays showed that cotransfection of bfMC1R with bfMC5R inhibited the cyclic AMP accumulation induced by α-MSH to a greater extent than that observed after transfection of bfMC1R alone. Of note, this inhibitory response was not caused by desacetyl-α-MSH. Thus, we show a ligand-dependent signaling through functional heterodimerization of MC1R and MC5R in mammalian cells. The ligand-selective receptor complex also provide the first mechanistic implication that may play a role in the control of color change in teleosts.
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Affiliation(s)
- Yuki Kobayashi
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
| | - Akie Hamamoto
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
| | | | - Yumiko Saito
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan.
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Caruso V, Lagerström MC, Olszewski PK, Fredriksson R, Schiöth HB. Synaptic changes induced by melanocortin signalling. Nat Rev Neurosci 2014; 15:98-110. [PMID: 24588018 DOI: 10.1038/nrn3657] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The melanocortin system has a well-established role in the regulation of energy homeostasis, but there is growing evidence of its involvement in memory, nociception, mood disorders and addiction. In this Review, we focus on the role of the melanocortin 4 receptor and provide an integrative view of the molecular mechanisms that lead to melanocortin-induced changes in synaptic plasticity within these diverse physiological systems. We also highlight the importance of melanocortin peptides and receptors in chronic pain syndromes, memory impairments, depression and drug abuse, and the possibility of targeting them for therapeutic purposes.
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Cheng LB, Cheng L, Bi HE, Zhang ZQ, Yao J, Zhou XZ, Jiang Q. Alpha-melanocyte stimulating hormone protects retinal pigment epithelium cells from oxidative stress through activation of melanocortin 1 receptor–Akt–mTOR signaling. Biochem Biophys Res Commun 2014; 443:447-52. [DOI: 10.1016/j.bbrc.2013.11.113] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 11/26/2013] [Indexed: 12/22/2022]
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Schwenk RW, Vogel H, Schürmann A. Genetic and epigenetic control of metabolic health. Mol Metab 2013; 2:337-47. [PMID: 24327950 PMCID: PMC3854991 DOI: 10.1016/j.molmet.2013.09.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 09/09/2013] [Accepted: 09/13/2013] [Indexed: 02/06/2023] Open
Abstract
Obesity is characterized as an excess accumulation of body fat resulting from a positive energy balance. It is the major risk factor for type 2 diabetes (T2D). The evidence for familial aggregation of obesity and its associated metabolic diseases is substantial. To date, about 150 genetic loci identified in genome-wide association studies (GWAS) are linked with obesity and T2D, each accounting for only a small proportion of the predicted heritability. However, the percentage of overall trait variance explained by these associated loci is modest (~5-10% for T2D, ~2% for BMI). The lack of powerful genetic associations suggests that heritability is not entirely attributable to gene variations. Some of the familial aggregation as well as many of the effects of environmental exposures, may reflect epigenetic processes. This review summarizes our current knowledge on the genetic basis to individual risk of obesity and T2D, and explores the potential role of epigenetic contribution.
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Key Words
- ADCY3, adenylate cyclase 3
- AQP9, aquaporin 9
- BDNF, brain-derived neurotrophic factor
- CDKAL1, CDK5 regulatory subunit associated protein 1-like 1
- CPEB4, cytoplasmic polyadenylation element binding protein 4
- DUSP22, dual specificity phosphatase 22
- DUSP8, dual specificity phosphatase 8
- Epigenetics
- GALNT10, UDP-N-acetyl-alpha-d-galactosamine:polypeptide N-acetylgalactosaminyltransferase 10 (GalNAc-T10)
- GIPR, gastric inhibitory polypeptide receptor
- GNPDA2, glucosamine-6-phosphate deaminase 2
- GP2, glycoprotein 2 (zymogen granule membrane)
- GWAS
- HIPK3, homeodomain interacting protein kinase 3
- IFI16, interferon, gamma-inducible protein 16
- KCNQ1, potassium voltage-gated channel, KQT-like subfamily, member 1
- KLHL32, kelch-like family member 32
- LEPR, leptin receptor
- MAP2K4, mitogen-activated protein kinase kinase 4
- MAP2K5, mitogen-activated protein kinase kinase 5
- MIR148A, microRNA 148a
- MMP9, matrix metallopeptidase 9 (gelatinase B, 92 kDa gelatinase, 92 kDa type IV collagenase)
- MNDA, myeloid cell nuclear differentiation antigen
- NFE2L3, nuclear factor, erythroid 2-like 3
- Obesity
- PACS1, phosphofurin acidic cluster sorting protein 1
- PAX6, paired box gene 6
- PCSK1, proprotein convertase subtilisin/kexin type 1
- PGC1α, peroxisome proliferative activated receptor, gamma, coactivator 1 alpha, PM2OD1
- PRKCH, protein kinase C, eta
- PRKD1, protein kinase D1
- PRKG1, protein kinase, cGMP-dependent, type I
- Positional cloning
- QPCTL, glutaminyl-peptide cyclotransferase-like
- RBJ, DnaJ (Hsp40) homolog, subfamily C, member 27
- RFC5, replication factor C (activator 1) 5
- RMST, rhabdomyosarcoma 2 associated transcript (non-protein coding)
- SEC16B, SEC16 homolog B
- TFAP2B, transcription factor AP-2 beta (activating enhancer binding protein 2 beta)
- TNNI3, troponin I type 3 (cardiac)
- TNNT1, troponin T type 1 (skeletal, slow)
- Type 2 diabetes
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Affiliation(s)
| | | | - Annette Schürmann
- Corresponding author. Tel.: +49 33200 882368; fax: +49 33200 882334.
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Zeltser LM, Seeley RJ, Tschöp MH. Synaptic plasticity in neuronal circuits regulating energy balance. Nat Neurosci 2012; 15:1336-42. [DOI: 10.1038/nn.3219] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Biebermann H, Kühnen P, Kleinau G, Krude H. The neuroendocrine circuitry controlled by POMC, MSH, and AGRP. Handb Exp Pharmacol 2012:47-75. [PMID: 22249810 DOI: 10.1007/978-3-642-24716-3_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Obesity is one of the most challenging health problems worldwide. Over the past few decades, our knowledge concerning mechanisms of weight regulation has increased tremendously leading to the identification of the leptin-melanocortin pathway. The filling level of energy stores is signaled to the brain, and the information is integrated by hypothalamic nuclei, resulting in a well-orchestrated response to food intake and energy expenditure to ensure constant body weight. One of the key players in this system is proopiomelanocortin (POMC), a precursor of a variety of neuropeptides. POMC-derived alpha- and beta-MSH play an important role in energy homeostasis by activating melanocortin receptors expressed in the arcuate nucleus (MC3R) and in the nucleus paraventricularis (MC4R). Activation of these two G protein-coupled receptors is antagonized by agouti-related peptide (AgRP). Naturally occurring mutations in this system were identified in patients suffering from common obesity as well as in patients demonstrating a phenotype of severe early-onset obesity, adrenal insufficiency, red hair, and pale skin. Detailed understanding of the complex system of POMC-AgRP-MC3R-MC4R and their interaction with other hypothalamic as well as peripheral signals is a prerequisite to combat the obesity epidemic.
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Affiliation(s)
- Heike Biebermann
- Institut für Experimentelle Pädiatrische Endokrinologie, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany.
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Kobayashi Y, Tsuchiya K, Yamanome T, Schiöth HB, Takahashi A. Differential expressions of melanocortin receptor subtypes in melanophores and xanthophores of barfin flounder. Gen Comp Endocrinol 2010; 168:133-42. [PMID: 20417636 DOI: 10.1016/j.ygcen.2010.04.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 04/16/2010] [Accepted: 04/20/2010] [Indexed: 11/16/2022]
Abstract
alpha-Melanocyte-stimulating hormone (alpha-MSH) is a member of the melanocortin (MC) family, and the MC receptor (MCR) is a member of the G protein-coupled receptor (GPCR) superfamily. We previously found that in barfin flounder, a flatfish, alpha-MSH with an acetyl group at the N-terminus stimulated pigment dispersion in xanthophores; however, this effect was not observed in melanophores. Therefore, the present study was undertaken to find which MCR subtypes are expressed in these pigment cells in order to elucidate how acetylation regulates activities of alpha-MSH-related peptides. Here, we also report the cloning of Mc1r and Mc5r from barfin flounder. Three types of cells-melanophores, xanthophores, and nonchromatophoric dermal cells-were isolated from the skin samples collected from the dorsal fin. These cells were then tested for the expression of Mc1r and Mc5r as well as Mc2r and Mc4r that we had previously cloned. Mc1r and Mc5r transcripts were detected in melanophores, and a sole Mc5r transcript was detected in xanthophores. We had previously found that the efficiency of alpha-MSH was higher than that of desacetyl-alpha-MSH for pigment dispersion in xanthophores. Acetylated MSH peptide may have increased binding affinity to MC5R, whereas alpha-MSH lacks melanin-dispersing activity. Increasing evidences indicate that many GPCRs form heterodimers, and this may affect the affinity of the ligand for the corresponding GPCR. Taken together, the expression of two different Mcr subtypes in melanophores may suggest that a heterodimer consisting of MC1R and MC5R may have a low binding affinity toward alpha-MSH. The present results clarify the types of MCRs that are expressed in melanophores and xanthophores of barfin flounder; furthermore, the results provide important clues about the functional regulation of alpha-MSH-related peptides.
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Affiliation(s)
- Yuki Kobayashi
- School of Marin Biosciences, Kitasato University, Ofunato, Iwate 022-0101, Japan
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13
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Abstract
Melanocortin peptides, derived from POMC (pro-opiomelanocortin) are produced in the ARH (arcuate nucleus of the hypothalamus) neurons and the neurons in the commissural NTS (nucleus of the solitary tract) of the brainstem, in anterior and intermediate lobes of the pituitary, skin and a wide range of peripheral tissues, including reproductive organs. A hypothetical model for functional roles of melanocortin receptors in maintaining energy balance was proposed in 1997. Since this time, there has been an extraordinary amount of knowledge gained about POMC-derived peptides in relation to energy homoeostasis. Development of a Pomc-null mouse provided definitive proof that POMC-derived peptides are critical for the regulation of energy homoeostasis. The melanocortin system consists of endogenous agonists and antagonists, five melanocortin receptor subtypes and receptor accessory proteins. The melanocortin system, as is now known, is far more complex than most of us could have imagined in 1997, and, similarly, the importance of this system for regulating energy homoeostasis in the general human population is much greater than we would have predicted. Of the known factors that can cause human obesity, or protect against it, the melanocortin system is by far the most significant. The present review is a discussion of the current understanding of the roles and mechanism of action of POMC, melanocortin receptors and AgRP (agouti-related peptide) in obesity and Type 2 diabetes and how the central and/or peripheral melanocortin systems mediate nutrient, leptin, insulin, gut hormone and cytokine regulation of energy homoeostasis.
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Nyan DC, Anbazhagan R, Hughes-Darden CA, Wachira SJM. Endosomal colocalization of melanocortin-3 receptor and beta-arrestins in CAD cells with altered modification of AKT/PKB. Neuropeptides 2008; 42:355-66. [PMID: 18291523 DOI: 10.1016/j.npep.2007.12.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Revised: 12/20/2007] [Accepted: 12/21/2007] [Indexed: 01/14/2023]
Abstract
The melanocortin 3-receptor is involved in regulating energy metabolism, body fluid composition and inflammatory responses. Melanocortin receptors function by activating membrane bound adenylate cyclase. However, the literature reports indicate that some G protein coupled receptors (GPCRs) can also activate mitogen activated protein kinase (MAPK) or phosphoinositide 3 kinase (PI3K) signaling pathways consequent to their endocytosis. These studies were undertaken to evaluate the role of these pathways in MC3R signaling in brain-stem neuronal cells. Recruitment of arrestins is implicated in the activation of secondary pathways by GPCRs and our data shows the colocalization of either arrestin B1 or B2 with MC3R in endosomes. An alteration in PKB phosphorylation pattern was observed in MC3R expressing cells independent of agonist stimulation. MC3R transfectants exhibited increased proliferation rates and inhibition of PKB pathway with triciribine abrogated cell proliferation in both vector control and MC3R transfectants. PKB is constitutively active in proliferating CAD cells but could be further activated by culturing the cells in differentiation medium. These studies suggest that the AKT/PKB pathway plays an important role in the proliferation of CAD cells and suggest a link between MC3R and cell growth pathways that may involve the alteration of AKT/PKB signaling pathway.
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Affiliation(s)
- D C Nyan
- Department of Biology, Morgan State University, Baltimore, MD 21251, USA
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15
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Wachira SJM, Guruswamy B, Uradu L, Hughes-Darden CA, Denaro FJ. Activation and endocytic internalization of melanocortin 3 receptor in neuronal cells. Ann N Y Acad Sci 2007; 1096:271-86. [PMID: 17405938 DOI: 10.1196/annals.1397.093] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Melanocortins play a central role in autonomic modulation of metabolism by acting through a family of highly homologous G protein-coupled receptors. Studies with gene knockout mice have implicated neural melanocortin receptors, MC3R and MC4R, in the etiology of obesity, insulin resistance, and salt-sensitive hypertension. In an attempt to better understand the mechanisms of function of these receptors, we expressed MC3R and MC4R in neuronal cells and demonstrated their co-localization to several membrane regions. We now show that in cultured neuronal cells, MC3R localizes to lipid rafts and undergoes endocytic internalization upon activation by gamma-MSH through a protein kinase-sensitive pathway. The appearance of the internalized receptor in lysosomes suggests that it is subsequently degraded. The expression of protein kinase A regulatory subunits and of c-Jun and c-Fos was analyzed by either immunoblotting or real-time PCR. No discernable changes were observed in the expression levels of these protein kinase A and protein kinase C responsive genes. Immunohistochemical studies showed a robust expression of MC3R protein in brain nuclei with relevance to cardiovascular function and fluid homeostasis further supporting the notion that the physiological effects of melanocortins on the cardiovascular system arise from effects on the central nervous system.
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Affiliation(s)
- S J M Wachira
- Department of Biology, Morgan State University, 1700 E. Cold Spring Lane, Baltimore, MD 21251, USA.
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Wu CSJ, Greenwood DR, Cooney JM, Jensen DJ, Tatnell MA, Cooper GJS, Mountjoy KG. Peripherally administered desacetyl alpha-MSH and alpha-MSH both influence postnatal rat growth and associated rat hypothalamic protein expression. Am J Physiol Endocrinol Metab 2006; 291:E1372-80. [PMID: 16868223 DOI: 10.1152/ajpendo.00480.2005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Desacetyl alpha-MSH predominates over alpha-MSH during development, but whether it is biologically active and has a physiological role is unclear. We compared the effects of 0.3 microg.g(-1).day(-1) desacetyl alpha-MSH with that of 0.3 microg.g(-1).day(-1) alpha-MSH on postnatal body growth by administering the peptides subcutaneously daily for postnatal days 0-14 and also used a two-dimensional gel electrophoresis gel-based proteomic approach to analyze protein changes in hypothalami, the relay center for body weight and growth regulation, after 14 days of treatment. We found that the growth rate between days 1 and 10 was significantly decreased by desacetyl alpha-MSH but not by alpha-MSH, but by day 14, a time reported for development of a mature pattern of hypothalamic innervation, both peptides had significantly increased neonatal growth compared with PBS-treated control rats. Desacetyl alpha-MSH significantly increased spleen weight, but alpha-MSH had no effect. alpha-MSH significantly decreased kidney weight, but desacetyl alpha-MSH had no effect. Both desacetyl alpha-MSH and alpha-MSH significantly decreased brain weight. By 14 days, both peptides significantly changed expression of a number of hypothalamic proteins, specifically metabolic enzymes, cytoskeleton, signaling, and stress response proteins. We show that peripherally administered desacetyl alpha-MSH is biologically active and induces responses that can differ from those for alpha-MSH. In conclusion, desacetyl alpha-MSH appears to be an important regulator of neonatal rat growth.
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Affiliation(s)
- Chia-Shan Jenny Wu
- Department of Physiology, University of Auckland, Auckland 1023, New Zealand
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Wilkinson CW. Roles of acetylation and other post-translational modifications in melanocortin function and interactions with endorphins. Peptides 2006; 27:453-71. [PMID: 16280185 DOI: 10.1016/j.peptides.2005.05.029] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2004] [Accepted: 05/13/2005] [Indexed: 10/25/2022]
Abstract
Phylogenetic, developmental, anatomic, and stimulus-specific variations in post-translational processing of POMC are well established. For melanocortins, the role of alpha-N-acetylation and the selective activities of alpha, beta, and gamma forms are of special interest. Acetylation may shift the predominant activity of POMC products between endorphinergic and melanocortinergic actions-which are often in opposition. This review addresses: (1) variations in POMC processing; (2) the influence of acetylation on the functional activity of alpha-MSH; (3) state- and stimulus-dependent effects on the proportional distribution of forms of melanocortins and endorphins; (4) divergent effects of alpha-MSH and beta-endorphin administration; (5) potential roles of beta- and gamma-MSH.
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Affiliation(s)
- Charles W Wilkinson
- Geriatric Research, Education and Clinical Center, VA Puget Sound Health Care System, Seattle, WA 98108, USA.
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van der Salm AL, Metz JR, Bonga SEW, Flik G. Alpha-MSH, the melanocortin-1 receptor and background adaptation in the Mozambique tilapia, Oreochromis mossambicus. Gen Comp Endocrinol 2005; 144:140-9. [PMID: 16019002 DOI: 10.1016/j.ygcen.2005.05.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2005] [Revised: 05/18/2005] [Accepted: 05/19/2005] [Indexed: 10/25/2022]
Abstract
The regulation of skin darkness in vertebrates is mediated by alpha-melanophore-stimulating-hormone (alphaMSH). For this action, alphaMSH binds to the melanocortin (MC)-1 receptor, a 7-transmembrane receptor located in melanophore cell membranes. The Mozambique tilapia, Oreochromis mossambicus, can change the hue of its body in response to a change in background, a process that may involve alphaMSH and the MC1R. Scale melanophores were isolated from tilapia that were acclimatised for 25 days to a black, control grey or white background and then tested for their sensitivity to des-, mono-, and di-acetylated alphaMSH. On all backgrounds, mono-acetylated alphaMSH was the dominant isoform present in pituitary homogenates. Mono-acetylated alphaMSH also had the highest potency to disperse melanosomes. Black background adapted fish showed the highest dispersing response to alphaMSH, independent of the isoform applied. We elucidated the nucleotide and amino acid sequence of the tilapia MC1R. We show that its expression in skin does not change when tilapia are acclimatised for 25 days to a black, grey or white background, while a clear change in hue is visible. This finding, combined with the absence of differential MC1R gene expression following background acclimation indicates that the increased sensitivity to alphaMSH is most likely a result of changes in the intracellular signalling system in melanophores of black background adapted fish, rather than up-regulation of the MC1R.
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Affiliation(s)
- A L van der Salm
- Department of Animal Physiology, Institute for Neuroscience, Faculty of Science, Radboud University Nijmegen, The Netherlands
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Dumont LM, Wu CSJ, Tatnell MA, Cornish J, Mountjoy KG. Evidence for direct actions of melanocortin peptides on bone metabolism. Peptides 2005; 26:1929-35. [PMID: 15979763 DOI: 10.1016/j.peptides.2004.12.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2004] [Accepted: 12/08/2004] [Indexed: 11/16/2022]
Abstract
Expression of melanocortin-4 receptor (MC4R) mRNA in developing rat limb buds, teeth, and skull bone first indicated a possible role for MC4R in bone metabolism. We therefore investigated whether MC4R mRNA was expressed in the rat osteosarcoma UMR106.06 cell line and in primary rat osteoblast cells. Reverse transcriptase-polymerase chain reaction (RT-PCR), Northern blot analysis, and ribonuclease protection assay (RPA) were used to demonstrate MC4R mRNA expression in UMR106.06 and primary osteoblast cells. MC4R mRNA was found to be localized to the periosteum of mouse bone using in situ hybridization. We also used RT-PCR and rat specific MC2R and MC5R oligonucleotides to amplify the correct size DNA fragments for these melanocortin receptors from rat primary osteoblasts. In conclusion, melanocortin receptor expression in mouse periosteum and rat osteoblasts suggests a direct role for POMC derived peptides in bone development and bone metabolism.
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MESH Headings
- Animals
- Blotting, Northern
- Bone and Bones/metabolism
- Cell Line, Tumor
- Cells, Cultured
- Mice
- Osteoblasts/metabolism
- Peptides/genetics
- Peptides/physiology
- Periosteum/metabolism
- Pro-Opiomelanocortin/metabolism
- Pro-Opiomelanocortin/physiology
- RNA, Messenger/biosynthesis
- Rats
- Receptor, Melanocortin, Type 2/biosynthesis
- Receptor, Melanocortin, Type 2/genetics
- Receptor, Melanocortin, Type 2/physiology
- Receptor, Melanocortin, Type 4/genetics
- Receptor, Melanocortin, Type 4/physiology
- Receptors, Corticotropin/biosynthesis
- Receptors, Corticotropin/genetics
- Receptors, Corticotropin/physiology
- Receptors, Melanocortin
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Affiliation(s)
- Laurence M Dumont
- Research Centre for Developmental Medical and Biology, Department of Paediatrics, University of Auckland, Auckland 1, New Zealand
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Ling MK, Hotta E, Kilianova Z, Haitina T, Ringholm A, Johansson L, Gallo-Payet N, Takeuchi S, Schiöth HB. The melanocortin receptor subtypes in chicken have high preference to ACTH-derived peptides. Br J Pharmacol 2004; 143:626-37. [PMID: 15466451 PMCID: PMC1575423 DOI: 10.1038/sj.bjp.0705900] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1 Melanocortin (MC) receptors are widely distributed throughout the body of chicken, like in mammals, and participate in a wide range of physiological functions. 2 To clarify the pharmacological impact of ligands acting in the MC system, we expressed the chicken MC1, MC2, MC3, MC4 and MC5 (cMC1-5) receptors in eukaryotic cells and performed comprehensive pharmacological characterization of the potency of endogenous and synthetic melanocortin peptides. 3 Remarkably, the cMC receptors displayed high affinity for ACTH-derived peptides and in general low affinity for alpha-MSH. It is evident that not only the cMC2 receptor but also the other cMC receptors interact with ACTH-derived peptide through an epitope beyond the sequence of alpha-MSH. 4 The synthetic ligand MTII was found to be a potent agonist whereas HS024 was a potent antagonist at the cMC4 receptor, indicating that these ligands are suitable for physiological studies in chicken. 5 We also show the presence of prohormone convertase 1 (PC1) and PC2 genes in chicken, and that these peptides are coexpressed with proopiomelanocortin (POMC) in various tissues.
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Affiliation(s)
- Maria K Ling
- Department of Neuroscience, Uppsala University, BMC, Box 593, 751 24 Uppsala, Sweden
| | - Eri Hotta
- Department of Biology, Faculty of Science, Okayama University, Okayama, Japan
| | - Zuzana Kilianova
- Service of Endocrinology, Department of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Tatjana Haitina
- Department of Neuroscience, Uppsala University, BMC, Box 593, 751 24 Uppsala, Sweden
| | - Aneta Ringholm
- Department of Neuroscience, Uppsala University, BMC, Box 593, 751 24 Uppsala, Sweden
| | - Lisa Johansson
- Department of Neuroscience, Uppsala University, BMC, Box 593, 751 24 Uppsala, Sweden
| | - Nicole Gallo-Payet
- Service of Endocrinology, Department of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Sakae Takeuchi
- Department of Biology, Faculty of Science, Okayama University, Okayama, Japan
| | - Helgi B Schiöth
- Department of Neuroscience, Uppsala University, BMC, Box 593, 751 24 Uppsala, Sweden
- Author for correspondence:
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Van der Salm AL, Pavlidis M, Flik G, Wendelaar Bonga SE. Differential release of alpha-melanophore stimulating hormone isoforms by the pituitary gland of red porgy, Pagrus pagrus. Gen Comp Endocrinol 2004; 135:126-33. [PMID: 14644652 DOI: 10.1016/j.ygcen.2003.09.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The best known actions of the pleiotrope alpha-melanophore stimulating hormone (alpha-MSH) are skin pigment regulation and corticotrope actions in the response to chronic stress. Stress-induced and enhanced release of alpha-MSH may therefore influence skin pigmentation and stress physiology simultaneously. The release of alpha-MSH is under multiple control by hypothalamic hormones and neurotransmitters. Thyrotropin releasing hormone (TRH), corticotropin releasing hormone (CRH), melanophore concentrating hormone (MCH), and dopamine (DA) have been tested in a superfusion set up for their potential to regulate alpha-MSH release from the pituitary gland of red porgy, Pagrus pagrus, in vitro. The release of alpha-MSH was stimulated by TRH and CRH, and was inhibited by MCH and DA. During unstimulated (basal) release, mono-acetylated alpha-MSH was the dominant form. During superfusion with secretagogues, we found that independent of their inhibitory or stimulatory capacity, isoform frequency did not change. MSH-isoform ratios were similar for all the substances that were used, except that both the inhibitory and the stimulatory factors increased the percentage of di-acetylated alpha-MSH at low concentrations (10(-11)M) when compared to their effects at high concentrations (10(-7)M).
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Affiliation(s)
- A L Van der Salm
- Department of Organismal Animal Physiology, University of Nijmegen, Toernooiveld 1, 6525 ED, Nijmegen, The Netherlands.
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