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Siddiqui J, Kinney CE, Han JC. The Genetics of Obesity. Pediatr Clin North Am 2024; 71:897-917. [PMID: 39343500 DOI: 10.1016/j.pcl.2024.06.001] [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] [Indexed: 10/01/2024]
Abstract
Understanding the genetic causes of obesity permits anticipatory guidance and targeted treatments. Children with hyperphagia and severe early-onset obesity should receive genetic testing for rare monogenic and syndromic disorders caused by pathogenic variants involving a single gene or single chromosomal region. Gene panels covering the leptin pathway, the key regulator of energy balance, are becoming more widely available and at lower cost. Polygenic obesity is much more common and involves multiple genes throughout the genome, although the overlap in genes for rare and common disorders suggests a spectrum of severity and the potential of shared precision medicine approaches for treatment.
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Affiliation(s)
- Juwairriyyah Siddiqui
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Mount Sinai Hospital, Diabetes, Obesity, and Metabolism Institute, Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Clint E Kinney
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Mount Sinai Hospital, Diabetes, Obesity, and Metabolism Institute, Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Joan C Han
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Mount Sinai Hospital, Diabetes, Obesity, and Metabolism Institute, Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA.
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2
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Rajeswari JJ, Faught E, Santos H, Vijayan MM. Mineralocorticoid receptor activates postnatal adiposity in zebrafish lacking proopiomelanocortin. J Cell Physiol 2024:e31428. [PMID: 39238189 DOI: 10.1002/jcp.31428] [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: 06/06/2024] [Revised: 08/14/2024] [Accepted: 08/26/2024] [Indexed: 09/07/2024]
Abstract
The proopiomelanocortin (Pomc)-derived peptides, including adrenocorticotropic hormone and α-melanocyte stimulating hormone (α-Msh), play both a central and a peripheral role in modulating the stress response. The central role is predominantly associated with nutrient homeostasis, while peripherally they play an important role in the synthesis of glucocorticoids (GCs) in response to stress. Pomc mutations are a major risk factor in the development of early-onset childhood obesity in humans. This is attributed primarily to their central effects on melanocortin receptor dysfunction leading to hyperphagia and reduced energy expenditure, while the peripheral mechanism contributing to obesity has largely been unexplored. Here, we tested the hypothesis that Pomc mutation-mediated adrenal insufficiency and the associated changes in GC signaling contribute to postnatal adiposity using zebrafish as a model. We generated a ubiquitous Pomc knockout zebrafish that mimicked the mammalian mutant phenotype of adrenal insufficiency and enhanced adiposity. The loss of Pomc inhibited stress-induced cortisol production and reprogrammed GC signaling by reducing glucocorticoid receptor responsiveness, whereas the mineralocorticoid receptor (Mr) signaling was enhanced. Larval feeding led to enhanced growth and adipogenesis in the Pomc mutants, and this was inhibited by eplerenone, an Mr antagonist. Altogether, our results underscore a key role for Mr signaling in early developmental adipogenesis and a possible target for therapeutic intervention for early-onset childhood obesity due to Pomc dysfunction.
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Affiliation(s)
- Jithine J Rajeswari
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Erin Faught
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Helio Santos
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
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Le Collen L, Delemer B, Poitou C, Vaxillaire M, Toussaint B, Dechaume A, Badreddine A, Boissel M, Derhourhi M, Clément K, Petit JM, Mau-Them FT, Bruel AL, Thauvin-Robinet C, Saveanu A, Cherifi BG, Le Beyec-Le Bihan J, Froguel P, Bonnefond A. Heterozygous pathogenic variants in POMC are not responsible for monogenic obesity: Implication for MC4R agonist use. Genet Med 2023; 25:100857. [PMID: 37092539 DOI: 10.1016/j.gim.2023.100857] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 04/15/2023] [Accepted: 04/16/2023] [Indexed: 04/25/2023] Open
Abstract
PURPOSE Recessive deficiency of proopiomelanocortin (POMC) causes childhood-onset severe obesity. Cases can now benefit from the melanocortin 4 receptor agonist setmelanotide. Furthermore, a phase 3 clinical trial is evaluating setmelanotide in heterozygotes for POMC. We performed a large-scale genetic analysis to assess the effect of heterozygous, pathogenic POMC variants on obesity. METHODS A genetic analysis was performed in a family including 2 cousins with childhood-onset obesity. We analyzed the obesity status of heterozygotes for pathogenic POMC variants in the Human Gene Mutation Database. The association between heterozygous pathogenic POMC variants and obesity risk was assessed using 190,000 exome samples from UK Biobank. RESULTS The 2 cousins carried a compound heterozygous pathogenic variant in POMC. Six siblings were heterozygotes; only 1 of them had obesity. In Human Gene Mutation Database, we identified 60 heterozygotes for pathogenic POMC variants, of whom 14 had obesity. In UK Biobank, heterozygous pathogenic POMC variants were not associated with obesity risk, but they modestly increased body mass index levels. CONCLUSION Heterozygous pathogenic POMC variants do not contribute to monogenic obesity, but they slightly increase body mass index. Setmelanotide use in patients with obesity, which would only be based on the presence of a heterozygous POMC variant, can be questioned.
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Affiliation(s)
- Lauriane Le Collen
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; Department of Endocrinology Diabetology, University Hospital Center of Reims, Reims, France; Department of Clinical Genetic, University Hospital Center of Reims, Reims, France; University of Lille, Lille, France.
| | - Brigitte Delemer
- Department of Endocrinology Diabetology, University Hospital Center of Reims, Reims, France
| | - Christine Poitou
- Assistance Publique Hôpitaux de Paris, Nutrition Department, Pitié-Salpêtrière Hospital, Paris, France; Sorbonne Université, INSERM, Nutrition and Obesities: Systemic Approaches Research Unit (NutriOmics), Paris, France
| | - Martine Vaxillaire
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France
| | - Bénédicte Toussaint
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France
| | - Aurélie Dechaume
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France
| | - Alaa Badreddine
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France
| | - Mathilde Boissel
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France
| | - Mehdi Derhourhi
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France
| | - Karine Clément
- Assistance Publique Hôpitaux de Paris, Nutrition Department, Pitié-Salpêtrière Hospital, Paris, France; Sorbonne Université, INSERM, Nutrition and Obesities: Systemic Approaches Research Unit (NutriOmics), Paris, France
| | - Jean M Petit
- Department of Endocrinology Diabetology, University Hospital Central of F. Mitterrand Dijon-Bourgogne, Dijon, France
| | - Frédéric Tran Mau-Them
- Unité Fonctionnelle Innovation en Diagnostic Génomique des maladies rares, CHU Dijon Bourgogne, Dijon, France; INSERM UMR1231 GAD, Dijon, France
| | - Ange-Line Bruel
- Unité Fonctionnelle Innovation en Diagnostic Génomique des maladies rares, CHU Dijon Bourgogne, Dijon, France; INSERM UMR1231 GAD, Dijon, France
| | - Christel Thauvin-Robinet
- Unité Fonctionnelle Innovation en Diagnostic Génomique des maladies rares, CHU Dijon Bourgogne, Dijon, France; INSERM UMR1231 GAD, Dijon, France; Centre de Référence Maladies Rares "Anomalies du développement et syndromes malformatifs," Centre de Génétique, FHU TRANSLAD et Institut GIMI, CHU Dijon Bourgogne, Dijon, France
| | - Alexandru Saveanu
- Aix-Marseille University, Institut National de la Santé et de la Recherche Médicale (INSERM), U1251, Marseille Medical Genetics (MMG), Marseille, France; Assistance Publique Hôpitaux de Marseille, Reference Center for Rare Pituitary Diseases HYPO, Marseille, France; Assistance-Publique des Hôpitaux de Marseille, Laboratory of Molecular Biology, Conception Hospital, Marseille, France
| | - Blandine Gatta Cherifi
- CHU Bordeaux, Endocrinology, Diabetology & Nutrition, Bordeaux, France; University of Bordeaux, Bordeaux, France; INSERMU1215 Neurocentre Magendie, University of Bordeaux, Bordeaux, France
| | - Johanne Le Beyec-Le Bihan
- Assistance Publique Hôpitaux de Paris, Endocrine and Oncological Biochemistry Department, Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France; INSERM U1149, Centre de recherche sur l'inflammation, Paris, France
| | - Philippe Froguel
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France; Department of Metabolism, Imperial College London, London, United Kingdom
| | - Amélie Bonnefond
- Inserm/CNRS UMR 1283/8199, Pasteur Institute of Lille, EGID, Lille, France; University of Lille, Lille, France; Department of Metabolism, Imperial College London, London, United Kingdom.
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Garnsey MR, Smith AC, Polivkova J, Arons AL, Bai G, Blakemore C, Boehm M, Buzon LM, Campion SN, Cerny M, Chang SC, Coffman K, Farley KA, Fonseca KR, Ford KK, Garren J, Kong JX, Koos MRM, Kung DW, Lian Y, Li MM, Li Q, Martinez-Alsina LA, O'Connor R, Ogilvie K, Omoto K, Raymer B, Reese MR, Ryder T, Samp L, Stevens KA, Widlicka DW, Yang Q, Zhu K, Fortin JP, Sammons MF. Discovery of the Potent and Selective MC4R Antagonist PF-07258669 for the Potential Treatment of Appetite Loss. J Med Chem 2023; 66:3195-3211. [PMID: 36802610 DOI: 10.1021/acs.jmedchem.2c02012] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The melanocortin-4 receptor (MC4R) is a centrally expressed, class A GPCR that plays a key role in the regulation of appetite and food intake. Deficiencies in MC4R signaling result in hyperphagia and increased body mass in humans. Antagonism of MC4R signaling has the potential to mitigate decreased appetite and body weight loss in the setting of anorexia or cachexia due to underlying disease. Herein, we report on the identification of a series of orally bioavailable, small-molecule MC4R antagonists using a focused hit identification effort and the optimization of these antagonists to provide clinical candidate 23. Introduction of a spirocyclic conformational constraint allowed for simultaneous optimization of MC4R potency and ADME attributes while avoiding the production of hERG active metabolites observed in early series leads. Compound 23 is a potent and selective MC4R antagonist with robust efficacy in an aged rat model of cachexia and has progressed into clinical trials.
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Affiliation(s)
| | - Aaron C Smith
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Jana Polivkova
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Autumn L Arons
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Guoyun Bai
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | - Markus Boehm
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Leanne M Buzon
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Sarah N Campion
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Matthew Cerny
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Shiao-Chi Chang
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Karen Coffman
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | - Kari R Fonseca
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Kristen K Ford
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Jeonifer Garren
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Jimmy X Kong
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Martin R M Koos
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Daniel W Kung
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Yajing Lian
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Monica M Li
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Qifang Li
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | | | - Kevin Ogilvie
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Kiyoyuki Omoto
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Brian Raymer
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Matthew R Reese
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Tim Ryder
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Lacey Samp
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | | | - Qingyi Yang
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Kaicheng Zhu
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
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Duis J, Butler MG. Syndromic and Nonsyndromic Obesity: Underlying Genetic Causes in Humans. Adv Biol (Weinh) 2022; 6:e2101154. [PMID: 35680611 DOI: 10.1002/adbi.202101154] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 03/13/2022] [Indexed: 01/28/2023]
Abstract
Growing evidence supports syndromic and nonsyndromic causes of obesity, including genome-wide association studies, candidate gene analysis, advanced genetic technology using next-generation sequencing (NGS), and identification of copy number variants. Identification of susceptibility genes impacts mechanistic understanding and informs precision medicine. The cause of obesity is heterogeneous with complex biological processes playing a role by controlling peptides involved in regulating appetite and food intake, cellular energy, and metabolism. Evidence for heritability shows genetic components contributing to 40%-70% of obesity. Monogenic causes and obesity-related syndromes are discussed and illustrated as well as biological pathways, gene interactions, and factors contributing to the obesity phenotype. Over 550 obesity-related single genes have been identified and summarized in tabular form with approximately 20% of these genes have been added to obesity gene panels for testing by commercially available laboratories. Early studies show that about 10% of patients with severe obesity using NGS testing have a pathogenic gene variant. Discussion to help characterize gene-gene interactions and disease mechanisms for early diagnosis, treatment, and risk factors contributing to disease is incorporated in this review.
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Affiliation(s)
- Jessica Duis
- Section of Genetics and Inherited Metabolic Disorders, Children's Hospital Colorado, University of Colorado, Anschutz Medical Campus, 13123 E 16th Ave, Aurora, CO, 80045, USA
| | - Merlin G Butler
- Division of Research and Genetics, Departments of Psychiatry & Behavioral Sciences and Pediatrics, University of Kansas Medical Center, 3901 Rainbow Boulevard, MS 4015, Kansas City, KS, 66160, USA
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6
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Mahmoud R, Kimonis V, Butler MG. Genetics of Obesity in Humans: A Clinical Review. Int J Mol Sci 2022; 23:11005. [PMID: 36232301 PMCID: PMC9569701 DOI: 10.3390/ijms231911005] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/09/2022] [Accepted: 09/10/2022] [Indexed: 11/23/2022] Open
Abstract
Obesity is a complex multifactorial disorder with genetic and environmental factors. There is an increase in the worldwide prevalence of obesity in both developed and developing countries. The development of genome-wide association studies (GWAS) and next-generation sequencing (NGS) has increased the discovery of genetic associations and awareness of monogenic and polygenic causes of obesity. The genetics of obesity could be classified into syndromic and non-syndromic obesity. Prader-Willi, fragile X, Bardet-Biedl, Cohen, and Albright Hereditary Osteodystrophy (AHO) syndromes are examples of syndromic obesity, which are associated with developmental delay and early onset obesity. Non-syndromic obesity could be monogenic, polygenic, or chromosomal in origin. Monogenic obesity is caused by variants of single genes while polygenic obesity includes several genes with the involvement of members of gene families. New advances in genetic testing have led to the identification of obesity-related genes. Leptin (LEP), the leptin receptor (LEPR), proopiomelanocortin (POMC), prohormone convertase 1 (PCSK1), the melanocortin 4 receptor (MC4R), single-minded homolog 1 (SIM1), brain-derived neurotrophic factor (BDNF), and the neurotrophic tyrosine kinase receptor type 2 gene (NTRK2) have been reported as causative genes for obesity. NGS is now in use and emerging as a useful tool to search for candidate genes for obesity in clinical settings.
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Affiliation(s)
- Ranim Mahmoud
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
- Department of Pediatrics, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Virginia Kimonis
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
- Departments of Neurology and Pathology, University of California, Irvine, CA 92697, USA
- Children’s Hospital of Orange County, Orange, CA 92868, USA
| | - Merlin G. Butler
- Departments of Psychiatry & Behavioral Sciences and Pediatrics, University of Kansas Medical Center, Kansas City, KS 66160, USA
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Mahoney P, McFarlane G, Loch C, White S, Floyd B, Dunn EC, Pitfield R, Nava A, Guatelli-Steinberg D. Dental biorhythm is associated with adolescent weight gain. COMMUNICATIONS MEDICINE 2022; 2:99. [PMID: 36016726 PMCID: PMC9395425 DOI: 10.1038/s43856-022-00164-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 07/26/2022] [Indexed: 12/02/2022] Open
Abstract
Background Evidence of a long-period biological rhythm present in mammalian hard tissue relates to species average body mass. Studies have just begun to investigate the role of this biorhythm in human physiology. Methods The biorhythm is calculated from naturally exfoliated primary molars for 61 adolescents. We determine if the timing relates to longitudinal measures of their weight, height, lower leg length and body mass collected over 14 months between September 2019 to October 2020. We use univariate and multivariate statistical analyses to isolate and identify relationships with the biorhythm. Results Participants with a faster biorhythm typically weigh less each month and gain significantly less weight and mass over 14-months, relative to those with a slower biorhythm. The biorhythm relates to sex differences in weight gain. Conclusions We identify a previously unknown factor that associates with the rapid change in body size that accompanies human adolescence. Our findings provide a basis from which to explore novel relationships between the biorhythm and weight-related health risks.
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Affiliation(s)
- Patrick Mahoney
- School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Gina McFarlane
- School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Carolina Loch
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Sophie White
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Bruce Floyd
- School of Social Sciences, University of Auckland, Auckland, New Zealand
| | - Erin C. Dunn
- Department of Psychiatry, Harvard Medical School and the Massachusetts General Hospital, Boston, MA USA
| | - Rosie Pitfield
- School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Alessia Nava
- School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Debbie Guatelli-Steinberg
- School of Anthropology and Conservation, University of Kent, Canterbury, UK
- Department of Anthropology, The Ohio State University, Columbus, OH USA
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Abstract
Pituitary autoimmunity is one of the principal causes of hypopituitarism. Additionally, hypophysitis is one of the immune-related adverse events associated with immunotherapy. Recent case-oriented research has revealed a novel type of autoimmune hypophysitis, anti-PIT-1 hypophysitis, related to isolated adrenocorticotropic hormone (ACTH) deficiency and immune checkpoint inhibitor-related hypophysitis, as a form of paraneoplastic syndrome. Under these conditions, the ectopic expression of pituitary antigens present in tumors evokes a breakdown of immune tolerance, resulting in the production of autoantibodies and autoreactive cytotoxic T cells that specifically harm pituitary cells. Consequently, an innovative clinical entity of paraneoplastic autoimmune hypophysitis has been purported. This novel concept and its underlying mechanisms provide clues for understanding the pathogenesis of autoimmune pituitary diseases and can be applied to other autoimmune diseases. This review discusses the etiology of paraneoplastic autoimmune hypophysitis and its future.
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Affiliation(s)
- Hironori Bando
- Division of Development of Advanced Therapy for Metabolic Diseases, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan; Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
| | - Keitaro Kanie
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
| | - Yutaka Takahashi
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan; Department of Diabetes and Endocrinology, Nara Medical University, Kashihara, Japan.
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Panera N, Mandato C, Crudele A, Bertrando S, Vajro P, Alisi A. Genetics, epigenetics and transgenerational transmission of obesity in children. Front Endocrinol (Lausanne) 2022; 13:1006008. [PMID: 36452324 PMCID: PMC9704419 DOI: 10.3389/fendo.2022.1006008] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/27/2022] [Indexed: 11/16/2022] Open
Abstract
Sedentary lifestyle and consumption of high-calorie foods have caused a relentless increase of overweight and obesity prevalence at all ages. Its presently epidemic proportion is disquieting due to the tight relationship of obesity with metabolic syndrome and several other comorbidities which do call for urgent workarounds. The usual ineffectiveness of present therapies and failure of prevention campaigns triggered overtime a number of research studies which have unveiled some relevant aspects of obesity genetic and epigenetic inheritable profiles. These findings are revealing extremely precious mainly to serve as a likely extra arrow to allow the clinician's bow to achieve still hitherto unmet preventive goals. Evidence now exists that maternal obesity/overnutrition during pregnancy and lactation convincingly appears associated with several disorders in the offspring independently of the transmission of a purely genetic predisposition. Even the pre-conception direct exposure of either father or mother gametes to environmental factors can reprogram the epigenetic architecture of cells. Such phenomena lie behind the transfer of the obesity susceptibility to future generations through a mechanism of epigenetic inheritance. Moreover, a growing number of studies suggests that several environmental factors such as maternal malnutrition, hypoxia, and exposure to excess hormones and endocrine disruptors during pregnancy and the early postnatal period may play critical roles in programming childhood adipose tissue and obesity. A deeper understanding of how inherited genetics and epigenetics may generate an obesogenic environment at pediatric age might strengthen our knowledge about pathogenetic mechanisms and improve the clinical management of patients. Therefore, in this narrative review, we attempt to provide a general overview of the contribution of heritable genetic and epigenetic patterns to the obesity susceptibility in children, placing a particular emphasis on the mother-child dyad.
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Affiliation(s)
- Nadia Panera
- Unit of Molecular Genetics of Complex Phenotypes, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Claudia Mandato
- Pediatrics Section, Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, Salermo, Italy
- *Correspondence: Anna Alisi, ; Claudia Mandato,
| | - Annalisa Crudele
- Unit of Molecular Genetics of Complex Phenotypes, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Sara Bertrando
- Pediatrics Clinic, San Giovanni di Dio e Ruggi d’Aragona University Hospital, Salerno, Italy
| | - Pietro Vajro
- Pediatrics Section, Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, Salermo, Italy
| | - Anna Alisi
- Unit of Molecular Genetics of Complex Phenotypes, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
- *Correspondence: Anna Alisi, ; Claudia Mandato,
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10
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Hsieh YW, Tsai YW, Lai HH, Lai CY, Lin CY, Her GM. Depletion of Alpha-Melanocyte-Stimulating Hormone Induces Insatiable Appetite and Gains in Energy Reserves and Body Weight in Zebrafish. Biomedicines 2021; 9:941. [PMID: 34440144 PMCID: PMC8392443 DOI: 10.3390/biomedicines9080941] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/24/2021] [Accepted: 07/27/2021] [Indexed: 12/23/2022] Open
Abstract
The functions of anorexigenic neurons secreting proopiomelanocortin (POMC)/alpha-melanocyte-stimulating hormone (α-MSH) of the melanocortin system in the hypothalamus in vertebrates are energy homeostasis, food intake, and body weight regulation. However, the mechanisms remain elusive. This article reports on zebrafish that have been genetically engineered to produce α-MSH mutants, α-MSH-7aa and α-MSH-8aa, selectively lacking 7 and 8 amino acids within the α-MSH region, but retaining most of the other normal melanocortin-signaling (Pomc-derived) peptides. The α-MSH mutants exhibited hyperphagic phenotypes leading to body weight gain, as observed in human patients and mammalian models. The actions of several genes regulating appetite in zebrafish are similar to those in mammals when analyzed using gene expression analysis. These include four selected orexigenic genes: Promelanin-concentrating hormone (pmch), agouti-related protein 2 (agrp2), neuropeptide Y (npy), and hypothalamic hypocretin/orexin (hcrt). We also study five selected anorexigenic genes: Brain-derived neurotrophic factor (bdnf), single-minded homolog 1-a (sim1a), corticotropin-releasing hormone b (crhb), thyrotropin-releasing hormone (trh), and prohormone convertase 2 (pcsk2). The orexigenic actions of α-MSH mutants are rescued completely after hindbrain ventricle injection with a synthetic analog of α-MSH and a melanocortin receptor agonist, Melanotan II. We evaluate the adverse effects of MSH depletion on energy balance using the Alamar Blue metabolic rate assay. Our results show that α-MSH is a key regulator of POMC signaling in appetite regulation and energy expenditure, suggesting that it might be a potential therapeutic target for treating human obesity.
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Affiliation(s)
- Yang-Wen Hsieh
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 202, Taiwan; (Y.-W.H.); (C.-Y.L.); (C.-Y.L.)
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Yi-Wen Tsai
- Department of Family Medicine, Chang Gung Memorial Hospital, Keelung 204, Taiwan;
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - Hsin-Hung Lai
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Chi-Yu Lai
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 202, Taiwan; (Y.-W.H.); (C.-Y.L.); (C.-Y.L.)
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Chiu-Ya Lin
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 202, Taiwan; (Y.-W.H.); (C.-Y.L.); (C.-Y.L.)
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Guor Mour Her
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
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11
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Graves LE, Khouri JM, Kristidis P, Verge CF. Proopiomelanocortin deficiency diagnosed in infancy in two boys and a review of the known cases. J Paediatr Child Health 2021; 57:484-490. [PMID: 33666293 DOI: 10.1111/jpc.15407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 01/17/2021] [Accepted: 02/04/2021] [Indexed: 11/28/2022]
Abstract
Proopiomelanocortin (POMC) deficiency is a rare monogenic disorder characterised by adrenocorticotropic hormone (ACTH) deficiency, red hair and hyperphagic obesity. Two unrelated cases presented with hypoglycaemia due to isolated ACTH deficiency in the neonatal period. POMC deficiency was suspected at age 2 years (c.133-2A>C) and at age 9 months (c.64del) due to infantile hyperphagic obesity. Neither patient had a convincing red hair phenotype at the time of diagnostic suspicion, illustrating the importance of suspecting POMC deficiency in isolated ACTH deficiency. Both patients have normal psychomotor development, whereas the only other reported case of c.64del had significant delay. This suggests, if ACTH deficiency is treated early in the neonatal period, that psychomotor retardation is not a part of the phenotype. We review 24 reported cases of POMC deficiency published to date. Although there is no current specific treatment for obesity in POMC deficiency, we anticipate that setmelanotide may be a useful future treatment option.
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Affiliation(s)
- Lara E Graves
- Department of Endocrinology, Sydney Children's Hospital, Sydney, New South Wales, Australia
| | - Joseph M Khouri
- Department of Paediatrics, Liverpool Hospital, Sydney, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Peter Kristidis
- Department of Paediatrics, Wollongong Hospital, Illawarra Shoalhaven Local Health District, Wollongong, New South Wales, Australia
| | - Charles F Verge
- Department of Endocrinology, Sydney Children's Hospital, Sydney, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, New South Wales, Australia
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12
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De Groot CJ, Poitou Bernert C, Coupaye M, Clement K, Paschou SA, Charmandari E, Kanaka-Gantenbein C, Wabitsch M, Buddingh EP, Nieuwenhuijsen B, Marina L, Johannsson G, Van Den Akker ELT. Clinical management of patients with genetic obesity during COVID-19 pandemic: position paper of the ESE Growth & Genetic Obesity COVID-19 Study Group and Rare Endo-ERN main thematic group on Growth and Obesity. Endocrine 2021; 71:653-662. [PMID: 33512658 PMCID: PMC7845285 DOI: 10.1007/s12020-021-02619-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 01/08/2021] [Indexed: 12/13/2022]
Abstract
This article aims to provide guidance on prevention and treatment of COVID-19 in patients with genetic obesity. Key principals of the management of patients with genetic obesity during COVID-19 pandemic for patients that have contracted COVID-19 are to be aware of: possible adrenal insufficiency (e.g., POMC deficiency, PWS); a more severe course in patients with concomitant immunodeficiency (e.g., LEP and LEPR deficiency), although defective leptin signalling could also be protective against the pro-inflammatory phenotype of COVID-19; disease severity being masked by insufficient awareness of symptoms in syndromic obesity patients with intellectual deficit (in particular PWS); to adjust medication dose to increased body size, preferably use dosing in m2; the high risk of malnutrition in patients with Sars-Cov2 infection, even in case of obesity. Key principals of the obesity management during the pandemic are to strive for optimal obesity management and a healthy lifestyle within the possibilities of the regulations to prevent weight (re)gain and to address anxiety within consultations, since prevalence of anxiety for COVID-19 is underestimated.
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Affiliation(s)
- Cornelis Jan De Groot
- Pediatric Endocrinology and Obesity Center CGG Erasmus MC, Rotterdam and Willem Alexander Children's Hospital, LUMC, Leiden, the Netherlands.
| | - Christine Poitou Bernert
- Assistance Publique-Hôpitaux de Paris, Reference Center for Rare Diseases (PRADORT, Prader-Willi Syndrome and other rare obesities), Nutrition Department, Pitié-Salpêtrière hospital, Paris, France
- Sorbonne Université/INSERM, Nutrition and obesities; systemic approaches (NutriOmics) research Unit, Paris, France
| | - Muriel Coupaye
- Assistance Publique-Hôpitaux de Paris, Reference Center for Rare Diseases (PRADORT, Prader-Willi Syndrome and other rare obesities), Nutrition Department, Pitié-Salpêtrière and Louis-Mourier hospitals, Paris, France
| | - Karine Clement
- Sorbonne Université/INSERM, Nutrition and obesities; systemic approaches (NutriOmics) research Unit, Paris, France
- Assistance Publique-Hopitaux de Paris, Nutrition Department, Pitie-Salpetriere Hospital, Paris, France
| | - Stavroula A Paschou
- Division of Endocrinology, Diabetes and Metabolism, Department of Clinical Therapeutics, Alexandra Hospital, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Evangelia Charmandari
- Pediatric and Adolescent Endocrinology, National and Kapodistrian University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece
- Division of Endocrinology, Center for Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, 11527, Greece
| | - Christina Kanaka-Gantenbein
- Division of Endocrinology, Diabetes and Metabolism, First Department of Pediatrics, Medical School, National and Kapodistrian University of Athens, Aghia Sophia Children's Hospital, Athens, Greece
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetes Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | | | | | - Ljiljana Marina
- Assistant Professor Clinic for Endocrinology, Diabetes and Metabolic Diseases, Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Gudmundur Johannsson
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg and Department of Endocrinology, Sahlgrenska University Hospital, SE-413 45, Gothenburg, Sweden
| | - E L T Van Den Akker
- Pediatric Endocrinology and Obesity Center CGG, Erasmus MC Sophia Children's Hospital, Rotterdam, the Netherlands.
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13
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Santos JL, Cortés VA. Eating behaviour in contrasting adiposity phenotypes: Monogenic obesity and congenital generalized lipodystrophy. Obes Rev 2021; 22:e13114. [PMID: 33030294 DOI: 10.1111/obr.13114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 07/13/2020] [Indexed: 12/11/2022]
Abstract
Most known types of nonsyndromic monogenic obesity are caused by rare mutations in genes of the leptin-melanocortin pathway controlling appetite and adiposity. In contrast, congenital generalized lipodystrophy represents the most extreme form of leanness in humans caused by recessive mutations in four genes involved in phospholipid/triglyceride synthesis and lipid droplet/caveolae structure. In this disease, the inability to store triglyceride in adipocytes results in hypoleptinemia and ectopic hepatic and muscle fat accumulation leading to fatty liver, hypertriglyceridemia and severe insulin resistance. As a result of hypoleptinemia, patients with lipodystrophy show alterations in eating behaviour characterized by constant increased energy intake. As it occurs in obesity caused by genetic leptin deficiency, exogenous leptin rapidly reduces hunger scores in patients with congenital generalized lipodystrophy, with additional beneficial effects on glucose homeostasis and metabolic profile normalization. The melanocortin-4 receptor agonist setmelanotide has been used in the treatment of monogenic obesities. There is only one report on the effect of setmelanotide in a patient with partial lipodystrophy resulting in mild reductions in hunger scores, with no improvements in metabolic status. The assessment of contrasting phenotypes of obesity/leanness represents an adequate strategy to understand the pathophysiology and altered eating behaviour associated with adipose tissue excessive accumulation/paucity.
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Affiliation(s)
- José L Santos
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Víctor A Cortés
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
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14
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Impact of Genetic Variations and Epigenetic Mechanisms on the Risk of Obesity. Int J Mol Sci 2020; 21:ijms21239035. [PMID: 33261141 PMCID: PMC7729759 DOI: 10.3390/ijms21239035] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 12/12/2022] Open
Abstract
Rare genetic obesity disorders are characterized by mutations of genes strongly involved in the central or peripheral regulation of energy balance. These mutations are effective in causing the early onset of severe obesity and insatiable hunger (hyperphagia), suggesting that the genetic component can contribute to 40–70% of obesity. However, genes’ roles in the processes leading to obesity are still unclear. This review is aimed to summarize the current knowledge of the genetic causes of obesity, especially monogenic obesity, describing the role of epigenetic mechanisms in obesity and metabolic diseases. A comprehensive understanding of the underlying genetic and epigenetic mechanisms, with the metabolic processes they control, will permit adequate management and prevention of obesity.
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15
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Müschen LH, Rhein M, Hoppe V, John N, Schwabe K, Frieling H, Bleich S, Muschler MAN. Alcohol Withdrawal and Proopiomelanocortin Neuropeptides in an Animal Model of Alcohol Dependence. Neuropsychobiology 2020; 78:118-127. [PMID: 31117084 DOI: 10.1159/000499844] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/19/2019] [Indexed: 12/30/2022]
Abstract
BACKGROUND Alcohol is one of the leading threats to health worldwide. Craving for alcohol makes abstinence a difficult challenge by maintaining alcohol dependence. Many studies suppose the hypothalamic-pituitary-adrenal axis, especially the proopiomelanocortin (POMC)-derived neuropeptides, to mediate craving during withdrawal in alcohol dependence. Evidence is available that the two POMC proteins, α-melanocyte-stimulating hormone (α-MSH) and β-endorphin (β-END) are altered by alcohol consumption and influence alcohol consumption, respectively. OBJECTIVES We investigated the dynamics of α-MSH and β-END during alcohol withdrawal and the influence of intraperitoneal administration of either α-MSH or β-END in an established rodent model (Wistar rats) for alcohol dependence. RESULTS After long-term alcohol self-administration over 12 months and repeated deprivation periods for 3 days, we found a significant decrease in α-MSH levels during withdrawal in rodents (p = 0.006) compared to controls, while β-END levels remained unchanged. Treatment with intraperitoneally administered α-MSH and β-END did not affect alcohol drinking behavior after deprivation. CONCLUSION We demonstrate the effects of alcohol deprivation on α-MSH in alcohol-dependent rodents, which appear to mimic α-MSH alteration found after fasting periods during appetite regulation. Therefore, low α-MSH levels are a possible indicator for craving in alcohol-dependent individuals and hence would be a potential target for anti-craving treatment.
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Affiliation(s)
- Lars Hendrik Müschen
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Departmentof Neurology, Hannover Medical School, Hannover, Germany
| | - Mathias Rhein
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany
| | - Viktoria Hoppe
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Department of Gynecology, Franziskus Hospital, Bielefeld, Germany
| | - Nadine John
- Department of Neurosurgery, Hannover Medical School, Hannover, Germany
| | - Kerstin Schwabe
- Department of Neurosurgery, Hannover Medical School, Hannover, Germany
| | - Helge Frieling
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany
| | - Stefan Bleich
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany
| | - Marc André Nicolas Muschler
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany, .,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany,
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16
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Solano ME, Arck PC. Steroids, Pregnancy and Fetal Development. Front Immunol 2020; 10:3017. [PMID: 32038609 PMCID: PMC6987319 DOI: 10.3389/fimmu.2019.03017] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 12/09/2019] [Indexed: 12/21/2022] Open
Abstract
Maternal glucocorticoids critically rise during pregnancy reaching up to a 20-fold increase of mid-pregnancy concentrations. Concurrently, another steroid hormone, progesterone, increases. Progesterone, which shows structural similarities to glucocorticoids, can bind the intracellular glucocorticoid receptor, although with lower affinity. Progesterone is essential for the establishment and continuation of pregnancy and it is generally acknowledged to promote maternal immune tolerance to fetal alloantigens through a wealth of immunomodulatory mechanisms. Despite the potent immunomodulatory capacity of glucocorticoids, little is known about their role during pregnancy. Here we aim to compare general aspects of glucocorticoids and progesterone during pregnancy, including shared common steroidogenic pathways, plasma transporters, regulatory pathways, expression of receptors, and mechanisms of action in immune cells. It was recently acknowledged that progesterone receptors are not ubiquitously expressed on immune cells and that pivotal features of progesterone induced- maternal immune adaptations to pregnancy are mediated via the glucocorticoid receptor, including e.g., T regulatory cells expansion. We hypothesize that a tight equilibrium between progesterone and glucocorticoids is critically required and recapitulate evidence supporting that their disequilibrium underlie pregnancy complications. Such a disequilibrium can occur, e.g., after maternal stress perception, which triggers the release of glucocorticoids and impair progesterone secretion, resulting in intrauterine inflammation. These endocrine misbalance might be interconnected, as increase in glucocorticoid synthesis, e.g., upon stress, may occur in detriment of progesterone steroidogenesis, by depleting the common precursor pregnenolone. Abundant literature supports that progesterone deficiency underlies pregnancy complications in which immune tolerance is challenged. In these settings, it is largely yet undefined if and how glucocorticoids are affected. However, although progesterone immunomodulation during pregnancy appear to be chiefly mediated glucocorticoid receptors, excess glucocorticoids cannot compensate by progesterone deficiency, indicating that additional und still undercover mechanisms are at play.
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Affiliation(s)
- Maria Emilia Solano
- Department for Obstetrics and Fetal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Petra Clara Arck
- Department for Obstetrics and Fetal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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17
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Abstract
Human skin and hair color are visible traits that can vary dramatically within and across ethnic populations. The genetic makeup of these traits-including polymorphisms in the enzymes and signaling proteins involved in melanogenesis, and the vital role of ion transport mechanisms operating during the maturation and distribution of the melanosome-has provided new insights into the regulation of pigmentation. A large number of novel loci involved in the process have been recently discovered through four large-scale genome-wide association studies in Europeans, two large genetic studies of skin color in Africans, one study in Latin Americans, and functional testing in animal models. The responsible polymorphisms within these pigmentation genes appear at different population frequencies, can be used as ancestry-informative markers, and provide insight into the evolutionary selective forces that have acted to create this human diversity.
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Affiliation(s)
- William J Pavan
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Richard A Sturm
- Dermatology Research Centre, The University of Queensland Diamantina Institute, The University of Queensland, Brisbane, Queensland 4102, Australia;
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18
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Barone I, Melani R, Mainardi M, Scabia G, Scali M, Dattilo A, Ceccarini G, Vitti P, Santini F, Maffei L, Pizzorusso T, Maffei M. Fluoxetine Modulates the Activity of Hypothalamic POMC Neurons via mTOR Signaling. Mol Neurobiol 2018; 55:9267-9279. [PMID: 29663284 DOI: 10.1007/s12035-018-1052-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 03/29/2018] [Indexed: 01/01/2023]
Abstract
Hypothalamic proopiomelanocortin (POMC) neurons are important players in the regulation of energy homeostasis; we previously demonstrated that environmental stimulation excites arcuate nucleus circuits to undergo plastic remodeling, leading to altered ratio between excitatory and inhibitory synaptic contacts on these neurons. The widely used selective serotonin reuptake inhibitor fluoxetine (FLX) is known to affect body weight. On the other hand, FLX administration mimics the effects of environmental stimulation on synaptic plasticity in the hippocampus and cortex. The mammalian target of rapamycin (mTOR) pathway is instrumental in these phenomena. Thus, we aimed at investigating whether and how FLX affects POMC neurons activity and hypothalamic mTOR function. Adult mice expressing green fluorescent protein (GFP) under the POMC promoter were treated with FLX for 3 weeks resulting in diminished body weight. Patch clamp recordings performed on POMC neurons indicate that FLX increases their firing rate and the excitatory AMPA-mediated transmission, and reduces the inhibitory GABAergic currents at presynaptic level. Immunofluorescence studies indicate that FLX increases the ratio between excitatory and inhibitory synaptic contacts on POMC neurons. These changes are associated with an increased activity of the hypothalamic mTOR pathway. Use of the mTOR inhibitor rapamycin blunts the effects of FLX on body weight and on functional and structural plasticity of POMC neurons. Our findings indicate that FLX is able to remodel POMC neurons, and that this may be partly mediated by the mTOR signaling pathway.
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Affiliation(s)
- Ilaria Barone
- Dulbecco Telethon Institute, Rome, Italy
- Department of Clinical and Experimental Medicine, Obesity Center at the Endocrinology Unit, Via Paradisa 2, 56126, Pisa, Italy
| | - Riccardo Melani
- Institute of Neuroscience, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy
| | - Marco Mainardi
- Institute of Neuroscience, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy
- Bio@SNS, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa, Italy
| | - Gaia Scabia
- Department of Clinical and Experimental Medicine, Obesity Center at the Endocrinology Unit, Via Paradisa 2, 56126, Pisa, Italy
- Institute of Clinical Physiology, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy
| | - Manuela Scali
- Institute of Neuroscience, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy
| | - Alessia Dattilo
- Department of Clinical and Experimental Medicine, Obesity Center at the Endocrinology Unit, Via Paradisa 2, 56126, Pisa, Italy
- Institute of Clinical Physiology, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy
| | - Giovanni Ceccarini
- Department of Clinical and Experimental Medicine, Obesity Center at the Endocrinology Unit, Via Paradisa 2, 56126, Pisa, Italy
| | - Paolo Vitti
- Department of Clinical and Experimental Medicine, Obesity Center at the Endocrinology Unit, Via Paradisa 2, 56126, Pisa, Italy
| | - Ferruccio Santini
- Department of Clinical and Experimental Medicine, Obesity Center at the Endocrinology Unit, Via Paradisa 2, 56126, Pisa, Italy
| | - Lamberto Maffei
- Institute of Neuroscience, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy
| | - Tommaso Pizzorusso
- Institute of Neuroscience, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy.
- NEUROFARBA Department, Università di Firenze, Via di San Savi 26, 50235, Florence, Italy.
| | - Margherita Maffei
- Dulbecco Telethon Institute, Rome, Italy.
- Department of Clinical and Experimental Medicine, Obesity Center at the Endocrinology Unit, Via Paradisa 2, 56126, Pisa, Italy.
- Institute of Clinical Physiology, National Research Council, Via Moruzzi 1, 56124, Pisa, Italy.
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19
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Çetinkaya S, Güran T, Kurnaz E, Keskin M, Sağsak E, Savaş Erdeve S, Suntharalingham JP, Buonocore F, Achermann JC, Aycan Z. A Patient with Proopiomelanocortin Deficiency: An Increasingly Important Diagnosis to Make. J Clin Res Pediatr Endocrinol 2018; 10:68-73. [PMID: 28739551 PMCID: PMC5838375 DOI: 10.4274/jcrpe.4638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Proopiomelanocortin (POMC) deficiency is a rare monogenic disorder with early-onset obesity. Investigation of this entity have increased our insight into the important role of the leptin-melanocortin pathway in energy balance. Here, we present a patient with POMC deficiency due to a homozygous c.206delC mutation in the POMC gene. We discuss the pathogenesis of this condition with emphasis on the crosstalk between hypothalamic and peripheral signals in the development of obesity and the POMC-melanocortin 4 receptors system as a target for therapeutic intervention.
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Affiliation(s)
- Semra Çetinkaya
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey,* Address for Correspondence: University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey GSM: +90 312 305 65 08 E-mail:
| | - Tülay Güran
- Marmara University Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Erdal Kurnaz
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | - Melikşah Keskin
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | - Elif Sağsak
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | - Senay Savaş Erdeve
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | | | - Federica Buonocore
- University College London, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - John C. Achermann
- University College London, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Zehra Aycan
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey,Yıldırım Beyazıt University Faculty of Medicine, Department of Pediatric Endocrinology, Ankara, Turkey
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20
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Saeed S, Arslan M, Froguel P. Genetics of Obesity in Consanguineous Populations: Toward Precision Medicine and the Discovery of Novel Obesity Genes. Obesity (Silver Spring) 2018; 26:474-484. [PMID: 29464904 DOI: 10.1002/oby.22064] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 09/05/2017] [Accepted: 09/30/2017] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Consanguinity has been instrumental in the elucidation of many Mendelian genetic diseases. Here, the unique advantage of consanguineous populations was considered in the quest for genes causing obesity. METHODS PubMed was searched for articles relevant to consanguinity and obesity published between 1995 and 2016. Some earlier articles of interest were also consulted. RESULTS Although obesity is the most heritable disorder, even in outbred populations, only 2% to 5% of severe obesity cases have so far been proven to be caused by single gene mutations. In some highly consanguineous populations, a remarkably higher proportion of obesity cases because of known and novel monogenic variants has been identified (up to 30%). CONCLUSIONS Combining the power conferred by consanguinity with current large-capacity sequencing techniques should bring new genetic factors and molecular mechanisms to the fore, unveiling a large part of the yet-elusive neurohumoral circuitry involved in the regulation of energy homeostasis and appetite. Importantly, the undertaking of such initiatives is destined to unfold novel targets for the development of precision medicine relevant to different forms of obesity.
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Affiliation(s)
- Sadia Saeed
- Department of Genomics of Common Disease, Imperial College London, London, UK
- CNRS, Pasteur Institute of Lille, University of Lille, Lille, France
| | - Muhammad Arslan
- Centre for Research in Molecular Medicine, The University of Lahore, Lahore, Pakistan
- Department of Biological Sciences, Forman Christian College, Lahore, Pakistan
| | - Philippe Froguel
- Department of Genomics of Common Disease, Imperial College London, London, UK
- CNRS, Pasteur Institute of Lille, University of Lille, Lille, France
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21
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Peeters B, Langouche L, Van den Berghe G. Adrenocortical Stress Response during the Course of Critical Illness. Compr Physiol 2017; 8:283-298. [DOI: 10.1002/cphy.c170022] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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22
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Sanders TR, Glendining KA, Jasoni CL. Obesity during pregnancy in the mouse alters the Netrin-1 responsiveness of foetal arcuate nucleus neuropeptide Y neurones. J Neuroendocrinol 2017; 29. [PMID: 29121420 DOI: 10.1111/jne.12556] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 10/16/2017] [Accepted: 11/03/2017] [Indexed: 12/26/2022]
Abstract
When individuals undergo gestation in an obese dam, they are at increased risk for impairments in the ability of the brain to regulate body weight. In rodents, gestation in an obese dam leads to a number of changes to the development of the hypothalamic neurones that regulate body weight, including reduced neuronal connectivity at birth. In the present study, we aimed to clarify how this neural circuitry develops normally, as well as to explore the mechanism underpinning the deficiency in connectivity seen in foetuses developing in obese dams. First, we developed an in vitro model for observing and manipulating the axonal growth of foetal arcuate nucleus (ARN) neuropeptide (NPY) neurones. We then used this model to test 2 hypotheses: (i) ARN NPY neurones respond to Netrin-1, one of a small number of axon growth and guidance factors that regulate neural circuit formation throughout the developing brain; and (ii) Netrin-1 responsiveness would be lost upon exposure to the inflammatory cytokine interleukin (IL)-6, which is elevated in foetuses developing in obese dams. We observed that ARN NPY neurones responded to Netrin-1 with a significant expansion of their growth cones, comprising the terminal apparatus that neurones use to navigate. Unexpectedly, we found further that NPY neurones from obese pregnancies had a reduced responsiveness to Netrin-1, raising the possibility that ARN NPY neurones from foetuses developing in obese dams were phenotypically different from normal NPY neurones. Finally, we observed that IL-6 treatment of normal NPY neurones in vitro led to a reduced growth cone responsiveness to Netrin-1, essentially causing them to behave similarly to NPY neurones from obese pregnancies. These results support the hypothesis that IL-6 can disrupt the normal process of axon growth from NPY neurones, and suggest one possible mechanism for how the body weight regulating circuitry fails to develop properly in the offspring of obese dams.
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Affiliation(s)
- T R Sanders
- Department of Anatomy, Centre for Neuroendocrinology, University of Otago School of Medical Sciences, Dunedin, New Zealand
| | - K A Glendining
- Department of Anatomy, Centre for Neuroendocrinology, University of Otago School of Medical Sciences, Dunedin, New Zealand
| | - C L Jasoni
- Department of Anatomy, Centre for Neuroendocrinology, University of Otago School of Medical Sciences, Dunedin, New Zealand
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Ericson MD, Lensing CJ, Fleming KA, Schlasner KN, Doering SR, Haskell-Luevano C. Bench-top to clinical therapies: A review of melanocortin ligands from 1954 to 2016. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2414-2435. [PMID: 28363699 PMCID: PMC5600687 DOI: 10.1016/j.bbadis.2017.03.020] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/21/2017] [Accepted: 03/27/2017] [Indexed: 10/19/2022]
Abstract
The discovery of the endogenous melanocortin agonists in the 1950s have resulted in sixty years of melanocortin ligand research. Early efforts involved truncations or select modifications of the naturally occurring agonists leading to the development of many potent and selective ligands. With the identification and cloning of the five known melanocortin receptors, many ligands were improved upon through bench-top in vitro assays. Optimization of select properties resulted in ligands adopted as clinical candidates. A summary of every melanocortin ligand is outside the scope of this review. Instead, this review will focus on the following topics: classic melanocortin ligands, selective ligands, small molecule (non-peptide) ligands, ligands with sex-specific effects, bivalent and multivalent ligands, and ligands advanced to clinical trials. Each topic area will be summarized with current references to update the melanocortin field on recent progress. This article is part of a Special Issue entitled: Melanocortin Receptors - edited by Ya-Xiong Tao.
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Affiliation(s)
- Mark D Ericson
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Cody J Lensing
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Katlyn A Fleming
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Katherine N Schlasner
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Skye R Doering
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
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Appetite responses to high-fat meals or diets of varying fatty acid composition: a comprehensive review. Eur J Clin Nutr 2017; 71:1154-1165. [DOI: 10.1038/ejcn.2016.250] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 09/02/2016] [Accepted: 09/26/2016] [Indexed: 02/08/2023]
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Zhang JP, Lencz T, Zhang RX, Nitta M, Maayan L, John M, Robinson DG, Fleischhacker WW, Kahn RS, Ophoff RA, Kane JM, Malhotra AK, Correll CU. Pharmacogenetic Associations of Antipsychotic Drug-Related Weight Gain: A Systematic Review and Meta-analysis. Schizophr Bull 2016; 42:1418-1437. [PMID: 27217270 PMCID: PMC5049532 DOI: 10.1093/schbul/sbw058] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Although weight gain is a serious but variable adverse effect of antipsychotics that has genetic underpinnings, a comprehensive meta-analysis of pharmacogenetics of antipsychotic-related weight gain is missing. In this review, random effects meta-analyses were conducted for dominant and recessive models on associations of specific single nucleotide polymorphisms (SNP) with prospectively assessed antipsychotic-related weight or body mass index (BMI) changes (primary outcome), or categorical increases in weight or BMI (≥7%; secondary outcome). Published studies, identified via systematic database search (last search: December 31, 2014), plus 3 additional cohorts, including 222 antipsychotic-naïve youth, and 81 and 141 first-episode schizophrenia adults, each with patient-level data at 3 or 4 months treatment, were meta-analyzed. Altogether, 72 articles reporting on 46 non-duplicated samples (n = 6700, mean follow-up = 25.1wk) with 38 SNPs from 20 genes/genomic regions were meta-analyzed (for each meta-analysis, studies = 2-20, n = 81-2082). Eleven SNPs from 8 genes were significantly associated with weight or BMI change, and 4 SNPs from 2 genes were significantly associated with categorical weight or BMI increase. Combined, 13 SNPs from 9 genes (Adrenoceptor Alpha-2A [ADRA2A], Adrenoceptor Beta 3 [ADRB3], Brain-Derived Neurotrophic Factor [BDNF], Dopamine Receptor D2 [DRD2], Guanine Nucleotide Binding Protein [GNB3], 5-Hydroxytryptamine (Serotonin) Receptor 2C [HTR2C], Insulin-induced gene 2 [INSIG2], Melanocortin-4 Receptor [MC4R], and Synaptosomal-associated protein, 25kDa [SNAP25]) were significantly associated with antipsychotic-related weight gain (P-values < .05-.001). SNPs in ADRA2A, DRD2, HTR2C, and MC4R had the largest effect sizes (Hedges' g's = 0.30-0.80, ORs = 1.47-1.96). Less prior antipsychotic exposure (pediatric or first episode patients) and short follow-up (1-2 mo) were associated with larger effect sizes. Individual antipsychotics did not significantly moderate effect sizes. In conclusion, antipsychotic-related weight gain is polygenic and associated with specific genetic variants, especially in genes coding for antipsychotic pharmacodynamic targets.
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Affiliation(s)
- Jian-Ping Zhang
- *To whom correspondence should be addressed; Division of Psychiatry Research, The Zucker Hillside Hospital, Northwell Health System, 75-59 263rd Street, Glen Oaks, NY 11020, US; tel: 718-470-8471, fax: 718-470-1905, e-mail:
| | | | - Ryan X. Zhang
- Department of Psychology and Neuroscience, Duke University, Durham, NY
| | - Masahiro Nitta
- Drug Development Division, Sumitomo Dainippon Pharma Co. Ltd, Tokyo, Japan
| | - Lawrence Maayan
- Department of Psychiatry, New York University School of Medicine, New York, NY
| | - Majnu John
- Division of Psychiatry Research, The Zucker Hillside Hospital, Northwell Health System, Glen Oaks, NY;,Center for Psychiatric Neuroscience, The Feinstein Institute for Medical Research, Manhasset, NY;,Department of Mathematics, Hofstra University, Hempstead, NY
| | | | | | - Rene S. Kahn
- Department of Psychiatry, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Roel A. Ophoff
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA
| | - John M. Kane
- Department of Psychiatry, Albert Einstein College of Medicine, Bronx, NY
| | | | - Christoph U. Correll
- Department of Psychiatry, Albert Einstein College of Medicine, Bronx, NY,Both authors contributed equally to the article
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San-Jose LM, Ducrest AL, Ducret V, Simon C, Richter H, Wakamatsu K, Roulin A. MC1R variants affect the expression of melanocortin and melanogenic genes and the association between melanocortin genes and coloration. Mol Ecol 2016; 26:259-276. [PMID: 27664794 DOI: 10.1111/mec.13861] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 09/07/2016] [Accepted: 09/14/2016] [Indexed: 12/13/2022]
Abstract
The melanocortin-1 receptor (MC1R) gene influences coloration by altering the expression of genes acting downstream in the melanin synthesis. MC1R belongs to the melanocortin system, a genetic network coding for the ligands that regulate MC1R and other melanocortin receptors controlling different physiological and behavioural traits. The impact of MC1R variants on these regulatory melanocortin genes was never considered, even though MC1R mutations could alter the influence of these genes on coloration (e.g. by decreasing MC1R response to melanocortin ligands). Using barn owl growing feathers, we investigated the differences between MC1R genotypes in the (co)expression of six melanocortin and nine melanogenic-related genes and in the association between melanocortin gene expression and phenotype (feather pheomelanin content). Compared to the MC1R rufous allele, responsible for reddish coloration, the white allele was not only associated with an expected lower expression of melanogenic-related genes (TYR, TYRP1, OCA2, SLC45A2, KIT, DCT) but also with a lower MC1R expression and a higher expression of ASIP, the MC1R antagonist. More importantly, the expression of PCSK2, responsible for the maturation of the MC1R agonist, α-melanocyte-stimulating hormone, was positively related to pheomelanin content in MC1R white homozygotes but not in individuals carrying the MC1R rufous allele. These findings indicate that MC1R mutations not only alter the expression of melanogenic-related genes but also the association between coloration and the expression of melanocortin genes upstream of MC1R. This suggests that MC1R mutations can modulate the regulation of coloration by the pleiotropic melanocortin genes, potentially decoupling the often-observed associations between coloration and other phenotypes.
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Affiliation(s)
- Luis M San-Jose
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Anne-Lyse Ducrest
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Valérie Ducret
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Céline Simon
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Hannes Richter
- Centre for Integrative Genomics, Genomic Technologies Facility, University of Lausanne, Genopode Building, CH-1015, Lausanne, Switzerland
| | - Kazumasa Wakamatsu
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, 470-1192, Japan
| | - Alexandre Roulin
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
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Epigenomic and metabolic responses of hypothalamic POMC neurons to gestational nicotine exposure in adult offspring. Genome Med 2016; 8:93. [PMID: 27609221 PMCID: PMC5015242 DOI: 10.1186/s13073-016-0348-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 08/23/2016] [Indexed: 01/06/2023] Open
Abstract
Background Epidemiological and animal studies have reported that prenatal nicotine exposure (PNE) leads to obesity and type-2 diabetes in offspring. Central leptin-melanocortin signaling via hypothalamic arcuate proopiomelanocortin (POMC) neurons is crucial for the regulation of energy and glucose balance. Furthermore, hypothalamic POMC neurons were recently found to mediate the anorectic effects of nicotine through activation of acetylcholine receptors. Here, we hypothesized that PNE impairs leptin-melanocortinergic regulation of energy balance in first-generation offspring by altering expression of long non-coding RNAs (lncRNAs) putatively regulating development and/or function of hypothalamic POMC neurons. Methods C57BL/6J females were exposed ad libitum to nicotine through drinking water and crossed with C57BL/6J males. Nicotine exposure was sustained during pregnancy and discontinued at parturition. Offspring development was monitored from birth into adulthood. From the age of 8 weeks, central leptin-melanocortin signaling, diabetes, and obesity susceptibility were assessed in male offspring fed a low-fat or high-fat diet for 16 weeks. Nicotine-exposed and non-exposed C57BL/6J females were also crossed with C57BL/6J males expressing the enhanced green fluorescent protein specifically in POMC neurons. Transgenic male offspring were subjected to laser microdissections and RNA sequencing (RNA-seq) analysis of POMC neurons for determination of nicotine-induced gene expression changes and regulatory lncRNA/protein-coding gene interactions. Results Contrary to expectation based on previous studies, PNE did not impair but rather enhanced leptin-melanocortinergic regulation of energy and glucose balance via POMC neurons in offspring. RNA-seq of laser microdissected POMC neurons revealed only one consistent change, upregulation of Gm15851, a lncRNA of yet unidentified function, in nicotine-exposed offspring. RNA-seq further suggested 82 cis-regulatory lncRNA/protein-coding gene interactions, 19 of which involved coding genes regulating neural development and/or function, and revealed expression of several previously unidentified metabolic, neuroendocrine, and neurodevelopment pathways in POMC neurons. Conclusions PNE does not result in obesity and type 2 diabetes but instead enhances leptin-melanocortinergic feeding and body weight regulation via POMC neurons in adult offspring. PNE leads to selective upregulation of Gm15851, a lncRNA, in adult offspring POMC neurons. POMC neurons express several lncRNAs and pathways possibly regulating POMC neuronal development and/or function. Electronic supplementary material The online version of this article (doi:10.1186/s13073-016-0348-2) contains supplementary material, which is available to authorized users.
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Kecel-Gunduz S, Celik S, Ozel AE, Akyuz S. The conformational and vibrational behavior of the inhibitory neuropeptide derived from beta-endorphin. J Biomol Struct Dyn 2016; 35:585-602. [DOI: 10.1080/07391102.2016.1154893] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Serda Kecel-Gunduz
- Science Faculty, Physics Department, Istanbul University, Vezneciler, 34134 Istanbul, Turkey
| | - Sefa Celik
- Engineering Faculty, Electrical-Electronics Engineering Department, Istanbul University, 34320 Avcilar, Istanbul, Turkey
| | - Aysen E. Ozel
- Science Faculty, Physics Department, Istanbul University, Vezneciler, 34134 Istanbul, Turkey
| | - Sevim Akyuz
- Science and Letters Faculty, Physics Department, Istanbul Kultur University, Atakoy Campus, Bakirkoy 34156, Istanbul, Turkey
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Peeters B, Boonen E, Langouche L, Van den Berghe G. The HPA axis response to critical illness: New study results with diagnostic and therapeutic implications. Mol Cell Endocrinol 2015; 408:235-40. [PMID: 25462585 DOI: 10.1016/j.mce.2014.11.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 11/18/2014] [Accepted: 11/19/2014] [Indexed: 10/24/2022]
Abstract
For decades, elevated plasma cortisol concentrations in critically ill patients were exclusively ascribed to a stimulated hypothalamus-pituitary-adrenal axis with increased circulating adrenocorticotropic hormone (ACTH) inferred to several-fold increase adrenal cortisol synthesis. However, 'ACTH-cortisol dissociation' has been reported during critical illness, referring to low circulating ACTH coinciding with elevated circulating cortisol. It was recently shown that metabolism of cortisol is significantly reduced in critically ill patients explained by a suppression of the activity and expression of cortisol metabolizing enzymes in kidney and liver. This reduced cortisol breakdown determines hypercortisolemia, much more than increased cortisol production, in the critically ill. Although the low plasma ACTH concentrations, evoked by the elevated plasma cortisol via feedback inhibition, are part of this adaptation, they may negatively affect adrenocortical structure and function in the prolonged phase of critical illness. These new insights have implications for diagnosis and treatment of adrenal insufficiency in critically ill patients.
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Affiliation(s)
- B Peeters
- Clinical Division and Laboratory of Intensive Care Medicine, Department Cellular and Molecular Medicine, KU Leuven University, Leuven B-3000, Belgium
| | - E Boonen
- Clinical Division and Laboratory of Intensive Care Medicine, Department Cellular and Molecular Medicine, KU Leuven University, Leuven B-3000, Belgium
| | - L Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department Cellular and Molecular Medicine, KU Leuven University, Leuven B-3000, Belgium
| | - G Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department Cellular and Molecular Medicine, KU Leuven University, Leuven B-3000, Belgium.
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Abstract
Although anti-inflammatory drugs are among the most common class of marketed drugs, chronic inflammatory conditions such as rheumatoid arthritis, multiple sclerosis or inflammatory bowel disease still represent unmet needs. New first-in-class drugs might be discovered in the future but the repurpose and further development of old drugs also offers promise for these conditions. This is the case of the melanocortin adrenocorticotropin hormone, ACTH, used in patients since 1952 but regarded as the last therapeutic option when other medications, such as glucocorticoids, cannot be used. Better understanding on its physiological and pharmacological mechanisms of actions and new insights on melanocortin receptors biology have revived the interest on rescuing this old and effective drug. ACTH does not only induce cortisol production, as previously assumed, but it also exerts anti-inflammatory actions by targeting melanocortin receptors present on immune cells. The endogenous agonists for these receptors (ACTH, α-, β-, and γ-melanocyte stimulating hormones), are also produced locally by immune cells, indicating the existence of an endogenous anti-inflammatory tissue-protective circuit involving the melanocortin system. These findings suggested that new ACTH-like melanocortin drugs devoid of steroidogenic actions, and hence side effects, could be developed. This review summarizes the actions of ACTH and melanocortin drugs, their role as endogenous pro-resolving mediators, their current clinical use and provides an overview on how recent advances on GPCR functioning may lead to a novel class of drugs.
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Abstract
The purpose of this article is to review fundamentals in adrenal gland histophysiology. Key findings regarding the important signaling pathways involved in the regulation of steroidogenesis and adrenal growth are summarized. We illustrate how adrenal gland morphology and function are deeply interconnected in which novel signaling pathways (Wnt, Sonic hedgehog, Notch, β-catenin) or ionic channels are required for their integrity. Emphasis is given to exploring the mechanisms and challenges underlying the regulation of proliferation, growth, and functionality. Also addressed is the fact that while it is now well-accepted that steroidogenesis results from an enzymatic shuttle between mitochondria and endoplasmic reticulum, key questions still remain on the various aspects related to cellular uptake and delivery of free cholesterol. The significant progress achieved over the past decade regarding the precise molecular mechanisms by which the two main regulators of adrenal cortex, adrenocorticotropin hormone (ACTH) and angiotensin II act on their receptors is reviewed, including structure-activity relationships and their potential applications. Particular attention has been given to crucial second messengers and how various kinases, phosphatases, and cytoskeleton-associated proteins interact to ensure homeostasis and/or meet physiological demands. References to animal studies are also made in an attempt to unravel associated clinical conditions. Many of the aspects addressed in this article still represent a challenge for future studies, their outcome aimed at providing evidence that the adrenal gland, through its steroid hormones, occupies a central position in many situations where homeostasis is disrupted, thus highlighting the relevance of exploring and understanding how this key organ is regulated. © 2014 American Physiological Society. Compr Physiol 4:889-964, 2014.
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Affiliation(s)
- Nicole Gallo-Payet
- Division of Endocrinology, Department of Medicine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, and Centre de Recherche Clinique Étienne-Le Bel of the Centre Hospitalier Universitaire de Sherbrooke (CHUS), Sherbrooke, Quebec, Canada
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Kim JD, Leyva S, Diano S. Hormonal regulation of the hypothalamic melanocortin system. Front Physiol 2014; 5:480. [PMID: 25538630 PMCID: PMC4260486 DOI: 10.3389/fphys.2014.00480] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 11/24/2014] [Indexed: 01/07/2023] Open
Abstract
Regulation of energy homeostasis is fundamental for life. In animal species and humans, the Central Nervous System (CNS) plays a critical role in such regulation by integrating peripheral signals and modulating behavior and the activity of peripheral organs. A precise interplay between CNS and peripheral signals is necessary for the regulation of food intake and energy expenditure in the maintenance of energy balance. Within the CNS, the hypothalamus is a critical center for monitoring, processing and responding to peripheral signals, including hormones such as ghrelin, leptin, and insulin. Once in the brain, peripheral signals regulate neuronal systems involved in the modulation of energy homeostasis. The main hypothalamic neuronal circuit in the regulation of energy metabolism is the melanocortin system. This review will give a summary of the most recent discoveries on the hormonal regulation of the hypothalamic melanocortin system in the control of energy homeostasis.
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Affiliation(s)
- Jung D Kim
- Departments of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine New Haven, CT, USA ; Program in Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine New Haven, CT, USA
| | - Stephanie Leyva
- Departments of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine New Haven, CT, USA ; Program in Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine New Haven, CT, USA
| | - Sabrina Diano
- Departments of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine New Haven, CT, USA ; Program in Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine New Haven, CT, USA ; Department of Neurobiology, Yale University School of Medicine New Haven, CT, USA ; Section of Comparative Medicine, Yale University School of Medicine New Haven, CT, USA
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Navarro-Alarcón M, Ruiz-Ojeda FJ, Blanca-Herrera RM, A-Serrano MM, Acuña-Castroviejo D, Fernández-Vázquez G, Agil A. Melatonin and metabolic regulation: a review. Food Funct 2014; 5:2806-32. [DOI: 10.1039/c4fo00317a] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Coll AP. “Are melanocortin receptors constitutively active in vivo?”. Eur J Pharmacol 2013; 719:202-207. [DOI: 10.1016/j.ejphar.2013.04.051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 03/22/2013] [Accepted: 04/03/2013] [Indexed: 10/26/2022]
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Abstract
Obesity is a disorder characterized by an excess accumulation of body fat resulting from a mismatch between energy intake and expenditure. Incidence of obesity has increased dramatically in the past few years, almost certainly fuelled by a shift in dietary habits owing to the widespread availability of low-cost, hypercaloric foods. However, clear differences exist in obesity susceptibility among individuals exposed to the same obesogenic environment, implicating genetic risk factors. Numerous genes have been shown to be involved in the development of monofactorial forms of obesity. In genome-wide association studies, a large number of common variants have been associated with adiposity levels, each accounting for only a small proportion of the predicted heritability. Although the small effect sizes of obesity variants identified in genome-wide association studies currently preclude their utility in clinical settings, screening for a number of monogenic obesity variants is now possible. Such regular screening will provide more informed prognoses and help in the identification of at-risk individuals who could benefit from early intervention, in evaluation of the outcomes of current obesity treatments, and in personalization of the clinical management of obesity. This Review summarizes current advances in obesity genetics and discusses the future of research in this field and the potential relevance to personalized obesity therapy.
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Pathogenesis of the metabolic syndrome: insights from monogenic disorders. Mediators Inflamm 2013; 2013:920214. [PMID: 23766565 PMCID: PMC3673346 DOI: 10.1155/2013/920214] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 04/18/2013] [Indexed: 12/16/2022] Open
Abstract
Identifying rare human metabolic disorders that result from a single-gene defect has not only enabled improved diagnostic and clinical management of such patients, but also has resulted in key biological insights into the pathophysiology of the increasingly prevalent metabolic syndrome. Insulin resistance and type 2 diabetes are linked to obesity and driven by excess caloric intake and reduced physical activity. However, key events in the causation of the metabolic syndrome are difficult to disentangle from compensatory effects and epiphenomena. This review provides an overview of three types of human monogenic disorders that result in (1) severe, non-syndromic obesity, (2) pancreatic beta cell forms of early-onset diabetes, and (3) severe insulin resistance. In these patients with single-gene defects causing their exaggerated metabolic disorder, the primary defect is known. The lessons they provide for current understanding of the molecular pathogenesis of the common metabolic syndrome are highlighted.
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Begriche K, Girardet C, McDonald P, Butler AA. Melanocortin-3 receptors and metabolic homeostasis. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 114:109-46. [PMID: 23317784 DOI: 10.1016/b978-0-12-386933-3.00004-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Attenuated activity of the central nervous melanocortin system causes obesity and insulin resistance. Obese rodents treated with melanocortins exhibit improvements in obesity and metabolic homeostasis that are not mutually dependent, suggesting metabolic actions that are independent of weight changes. These responses are generally thought to involve G-protein-coupled receptors expressed in the brain. Melanocortin-4 receptors (MC4Rs) regulate satiety and autonomic nervous system and thyroid function. MC3Rs are expressed in hypothalamic and limbic regions involved in controlling ingestive behaviors and autonomic function. Mc3r-/- mice exhibit increased adiposity and an accelerated diet-induced obesity. While this phenotype is not dependent on hyperphagia, data on the regulation of food intake by MC3Rs are inconsistent. Recent investigations by our laboratory suggest a unique combination of behavioral and metabolic disorders in Mc3r-/- mice. MC3Rs are critical for the expression of the anticipatory response and metabolic homeostasis when food intake occurs outside the normal voluntary rhythms driven by photoperiod. Using a Cre-Lox strategy, we can now investigate MC3Rs expressed in different brain regions and organ systems in the periphery. While focusing on the functions of neural MC3Rs, early results suggest an additional layer of complexity with central and peripheral MC3Rs involved in the defense of body weight.
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Affiliation(s)
- Karima Begriche
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, Florida, USA
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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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Early onset obesity and adrenal insufficiency associated with a homozygous POMC mutation. INTERNATIONAL JOURNAL OF PEDIATRIC ENDOCRINOLOGY 2011; 2011:5. [PMID: 21860632 PMCID: PMC3159139 DOI: 10.1186/1687-9856-2011-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 07/06/2011] [Indexed: 11/10/2022]
Abstract
Isolated hypocortisolism due to ACTH deficiency is a rare condition that can be caused by homozygous or compound heterozygous mutations in the gene encoding proopiomelanocortin (POMC). Loss of function mutations of POMC gene typically results in adrenal insufficiency, obesity and red hair. We describe an 18 month old Hispanic female with congenital adrenal insufficiency, a novel POMC mutation and atypical clinical features. The patient presented at the age of 9 months with hypoglycemia and the endocrine evaluation resulted in a diagnosis of ACTH deficiency. She developed extreme weight gain prompting sequence analysis of POMC, which revealed a homozygous c.231C > A change which is predicted to result in a premature termination codon. The case we report had obesity, hypocortisolism but lacked red hair which is typical for subjects with POMC mutations. Mutations of POMC should be considered in individuals with severe early onset obesity and adrenal insufficiency even when they lack the typical pigmentary phenotype.
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Stevens A, Begum G, White A. Epigenetic changes in the hypothalamic pro-opiomelanocortin gene: a mechanism linking maternal undernutrition to obesity in the offspring? Eur J Pharmacol 2011; 660:194-201. [PMID: 21211530 DOI: 10.1016/j.ejphar.2010.10.111] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 10/06/2010] [Accepted: 10/29/2010] [Indexed: 11/28/2022]
Abstract
Maternal undernutrition is associated with programming of obesity in offspring. While previous evidence has linked programming to the hypothalamic, pituitary, and adrenal (HPA) axis it could also affect the hypothalamic neuropeptides which regulate food intake and energy balance. Alpha melanocyte stimulating hormone (αMSH), a key regulator of these neuronal pathways, is derived from pro-opiomelanocortin (POMC) which is therefore a prime target for the programming of obesity. Several models of maternal undernutrition have identified changes in POMC in hypothalami from foetuses or offspring at various ages. These models have also shown that the offspring go on to develop obesity and/or glucose intolerance. It is our hypothesis that programming leads to epigenetic changes in hypothalamic neuropeptide genes. Therefore when there is subsequent increased food availability, the epigenetic changes could cause dysfunctional transcriptional regulation of energy balance. We present evidence of epigenetic changes in the POMC gene promoter in foetal hypothalami after peri-conceptional undernutrition. In this model there are also epigenetic changes in the hypothalamic glucocorticoid receptor with consequent up-regulation of the receptor which could lead to alterations in the regulation of POMC and neuropeptide Y (NPY) in the hypothalamus. Thus maternal undernutrition could cause epigenetic changes in the POMC and glucocorticoid receptor genes, in the foetal hypothalamus, which may predispose the offspring to altered regulation of food intake, energy expenditure and glucose homeostasis, later in life.
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Affiliation(s)
- Adam Stevens
- Faculty of Medical and Human Sciences, University of Manchester, UK
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41
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Melanocortins and body weight regulation: glucocorticoids, Agouti-related protein and beyond. Eur J Pharmacol 2011; 660:111-8. [PMID: 21199644 DOI: 10.1016/j.ejphar.2010.10.103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 09/29/2010] [Accepted: 10/12/2010] [Indexed: 11/20/2022]
Abstract
In the intervening three decades since Panksepp observed for the first time that centrally administered α-melanocyte stimulating hormone decreased food intake (Panksepp and Meeker, 1976), a wealth of data have accrued to firmly establish melanocortin signaling as a central regulator of food intake and fat mass. Advances in molecular biology have not only allowed detailed studies of spontaneously occurring obese mice with altered melanocortin signaling to be undertaken but also permitted the generation of a plethora of mouse models with precise perturbations at critical steps in the melanocortin system to finesse further the cellular and molecular architecture of relevant pathways. In this article we focus in upon a number of these mouse models which continue to help us tease apart the complexities of this critical system. Further, we review data on the important interaction between pro-opiomelanocortin derived peptides and the adrenal system and the relationship between agonist and antagonist peptides acting at central melanocortin receptors.
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Gao X, Chen J. Conditional knockout of brain-derived neurotrophic factor in the hippocampus increases death of adult-born immature neurons following traumatic brain injury. J Neurotrauma 2010; 26:1325-35. [PMID: 19203227 DOI: 10.1089/neu.2008.0744] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
It has been reported that the hippocampus is particularly vulnerable to traumatic brain injury (TBI), the consequence of which results in hippocampal-dependent cognitive impairment. In the previous study we found that adult-born immature neurons in the hippocampal dentate gyrus are the most vulnerable cell type to moderate TBI insult. However, the molecular mechanisms that regulate the survival of adult-born immature neurons in the hippocampus following TBI are still not well understood. Here, we conditionally knocked out brain-derived neurotrophic factor (BDNF) in the hippocampal dentate gyrus and examined the death of adult-born immature neurons following moderate TBI. The results showed that the amount of adult-born immature neuron death in the hippocampal dentate gyrus significantly increased in the BDNF conditional knockout mice. This result suggests that BDNF is involved in regulating the survival of adult-born immature neurons in the hippocampus following TBI, and potentially might be a useful target for preventing the adult-born immature neurons from death following TBI.
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Affiliation(s)
- Xiang Gao
- Spinal Cord and Brain Injury Research Group, Indiana University, Indianapolis, IN 46202, USA
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Stevens A, Begum G, Cook A, Connor K, Rumball C, Oliver M, Challis J, Bloomfield F, White A. Epigenetic changes in the hypothalamic proopiomelanocortin and glucocorticoid receptor genes in the ovine fetus after periconceptional undernutrition. Endocrinology 2010; 151:3652-64. [PMID: 20573728 DOI: 10.1210/en.2010-0094] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Maternal food restriction is associated with the development of obesity in offspring. This study examined how maternal undernutrition in sheep affects the fetal hypothalamic glucocorticoid receptor (GR) and the appetite-regulating neuropeptides, proopiomelanocortin (POMC) and neuropeptide Y, which it regulates. In fetuses from ewes undernourished from -60 to +30 d around conception, there was increased histone H3K9 acetylation (1.63-fold) and marked hypomethylation (62% decrease) of the POMC gene promoter but no change in POMC expression. In the same group, acetylation of histone H3K9 associated with the hypothalamic GR gene was increased 1.60-fold and the GR promoter region was hypomethylated (53% decrease). In addition, there was a 4.7-fold increase in hypothalamic GR expression but no change in methylation of GR gene expression in the anterior pituitary or hippocampus. Interestingly, hypomethylation of both POMC and GR promoter markers in fetal hypothalami was also identified after maternal undernutrition from -60 to 0 d and -2 to +30 d. In comparison, the Oct4 gene, was hypermethylated in both control and underfed groups. Periconceptional undernutrition is therefore associated with marked epigenetic changes in hypothalamic genes. Increase in GR expression in the undernourished group may contribute to fetal programming of a predisposition to obesity, via altered GR regulation of POMC and neuropeptide Y. These epigenetic changes in GR and POMC in the hypothalamus may also predispose the offspring to altered regulation of food intake, energy expenditure, and glucose homeostasis later in life.
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Affiliation(s)
- Adam Stevens
- Faculties of Life Sciences and Medical and Human Sciences, Manchester Academic Health Sciences Centre, University of Manchester, Manchester M13 9PT, UK
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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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Beales PL. Obesity in Single Gene Disorders. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 94:125-57. [DOI: 10.1016/b978-0-12-375003-7.00005-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Hook V, Funkelstein L, Toneff T, Mosier C, Hwang SR. Human pituitary contains dual cathepsin L and prohormone convertase processing pathway components involved in converting POMC into the peptide hormones ACTH, alpha-MSH, and beta-endorphin. Endocrine 2009; 35:429-37. [PMID: 19343278 PMCID: PMC2731682 DOI: 10.1007/s12020-009-9163-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 01/16/2009] [Accepted: 02/23/2009] [Indexed: 01/30/2023]
Abstract
The production of the peptide hormones ACTH, alpha-MSH, and beta-endorphin requires proteolytic processing of POMC which is hypothesized to utilize dual cysteine- and subtilisin-like protease pathways, consisting of the secretory vesicle cathepsin L pathway and the well-known subtilisin-like prohormone convertase (PC) pathway. To gain knowledge of these protease components in human pituitary where POMC-derived peptide hormones are produced, this study investigated the presence of these protease pathway components in human pituitary. With respect to the cathepsin L pathway, human pituitary contained cathepsin L of 27-29 kDa and aminopeptidase B of approximately 64 kDa, similar to those in secretory vesicles of related neuroendocrine tissues. The serpin inhibitor endopin 2, a selective inhibitor of cathepsin L, was also present. With respect to the PC pathway, human pituitary expresses PC1/3 and PC2 of approximately 60-65 kDa, which represent active PC1/3 and PC2; peptide hormone production then utilizes carboxypeptidase E (CPE) which is present as a protein of approximately 55 kDa. Analyses of POMC products in human pituitary showed that they resemble those in mouse pituitary which utilizes cathepsin L and PC2 for POMC processing. These findings suggest that human pituitary may utilize the cathepsin L and prohormone convertase pathways for producing POMC-derived peptide hormones.
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Affiliation(s)
- Vivian Hook
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, CA 92093-0744, USA.
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Kim AC, Barlaskar FM, Heaton JH, Else T, Kelly VR, Krill KT, Scheys JO, Simon DP, Trovato A, Yang WH, Hammer GD. In search of adrenocortical stem and progenitor cells. Endocr Rev 2009; 30:241-63. [PMID: 19403887 PMCID: PMC2726842 DOI: 10.1210/er.2008-0039] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Scientists have long hypothesized the existence of tissue-specific (somatic) stem cells and have searched for their location in different organs. The theory that adrenocortical organ homeostasis is maintained by undifferentiated stem or progenitor cells can be traced back nearly a century. Similar to other organ systems, it is widely believed that these rare cells of the adrenal cortex remain relatively undifferentiated and quiescent until needed to replenish the organ, at which time they undergo proliferation and terminal differentiation. Historical studies examining cell cycle activation by label retention assays and regenerative potential by organ transplantation experiments suggested that the adrenocortical progenitors reside in the outer periphery of the adrenal gland. Over the past decade, the Hammer laboratory, building on this hypothesis and these observations, has endeavored to understand the mechanisms of adrenocortical development and organ maintenance. In this review, we summarize the current knowledge of adrenal organogenesis. We present evidence for the existence and location of adrenocortical stem/progenitor cells and their potential contribution to adrenocortical carcinomas. Data described herein come primarily from studies conducted in the Hammer laboratory with incorporation of important related studies from other investigators. Together, the work provides a framework for the emerging somatic stem cell field as it relates to the adrenal gland.
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Affiliation(s)
- Alex C Kim
- Department of Internal Medicine, Division of Metabolism, Ann Arbor, Michigan 48109-2200, USA
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48
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Gao X, Chen J. Conditional knockout of brain-derived neurotrophic factor in the hippocampus increases death of adult-born immature neurons following traumatic brain injury. J Neurotrauma 2009. [DOI: 10.1089/neu.2008-0744] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Haskell-Luevano C, Schaub JW, Andreasen A, Haskell KR, Moore MC, Koerper LM, Rouzaud F, Baker HV, Millard WJ, Walter G, Litherland SA, Xiang Z. Voluntary exercise prevents the obese and diabetic metabolic syndrome of the melanocortin-4 receptor knockout mouse. FASEB J 2008; 23:642-55. [PMID: 18971258 DOI: 10.1096/fj.08-109686] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Exercise is a mechanism for maintenance of body weight in humans. Morbidly obese human patients have been shown to possess single nucleotide polymorphisms in the melanocortin-4 receptor (MC4R). MC4R knockout mice have been well characterized as a genetic model that possesses phenotypic metabolic disorders, including obesity, hyperphagia, hyperinsulinemia, and hyperleptinemia, similar to those observed in humans possessing dysfunctional hMC4Rs. Using this model, we examined the effect of voluntary exercise of MC4R knockout mice that were allowed access to a running wheel for a duration of 8 wk. Physiological parameters that were measured included body weight, body composition of fat and lean mass, food consumption, body length, and blood levels of cholesterol and nonfasted glucose, insulin, and leptin. At the termination of the experiment, hypothalamic mRNA expression levels of neuropeptide Y (NPY), agouti-related protein (AGRP), proopiomelanocortin (POMC), cocaine- and amphetamine-regulated transcript (CART), orexin, brain-derived neurotropic factor (BDNF), phosphatase with tensin homology (Pten), melanocortin-3 receptor (MC3R), and NPY-Y1R were determined. In addition, islet cell distribution and function in the pancreas were examined. In the exercising MC4R knockout mice, the pancreatic islet cell morphology and other physiological parameters resembled those observed in the wild-type littermate controls. Gene expression profiles identified exercise as having a significant effect on hypothalamic POMC, orexin, and MC3R levels. Genotype had a significant effect on AGRP, POMC, CART, and NPY-Y1R, with an exercise and genotype interaction effect on NPY gene expression. These data support the hypothesis that voluntary exercise can prevent the genetic predisposition of melanocortin-4 receptor-associated obesity and diabetes.
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Affiliation(s)
- Carrie Haskell-Luevano
- Department of Pharmacodynamics, University of Florida, PO Box 100487, Gainesville, FL 32610, USA.
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50
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Abstract
Imaging mass spectrometry combines the chemical specificity and parallel detection of mass spectrometry with microscopic imaging capabilities. The ability to simultaneously obtain images from all analytes detected, from atomic to macromolecular ions, allows the analyst to probe the chemical organization of a sample and to correlate this with physical features. The sensitivity of the ionization step, sample preparation, the spatial resolution, and the speed of the technique are all important parameters that affect the type of information obtained. Recently, significant progress has been made in each of these steps for both secondary ion mass spectrometry (SIMS) and matrix-assisted laser desorption/ionization (MALDI) imaging of biological samples. Examples demonstrating localization of proteins in tumors, a reduction of lamellar phospholipids in the region binding two single celled organisms, and sub-cellular distributions of several biomolecules have all contributed to an increasing upsurge in interest in imaging mass spectrometry. Here we review many of the instrumental developments and methodological approaches responsible for this increased interest, compare and contrast the information provided by SIMS and MALDI imaging, and discuss future possibilities.
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Affiliation(s)
- Liam A McDonnell
- FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, The Netherlands
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