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Alonso AM, Cork SC, Phuah P, Hansen B, Norton M, Cheng S, Xu X, Suba K, Ma Y, Dowsett GK, Tadross JA, Lam BY, Yeo GS, Herzog H, Bloom SR, Arnold M, Distaso W, Murphy KG, Salem V. The vagus nerve mediates the physiological but not pharmacological effects of PYY 3-36 on food intake. Mol Metab 2024; 81:101895. [PMID: 38340808 PMCID: PMC10877939 DOI: 10.1016/j.molmet.2024.101895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 01/25/2024] [Accepted: 02/02/2024] [Indexed: 02/12/2024] Open
Abstract
Peptide YY (PYY3-36) is a post-prandially released gut hormone with potent appetite-reducing activity, the mechanism of action of which is not fully understood. Unravelling how this system physiologically regulates food intake may help unlock its therapeutic potential, whilst minimising unwanted effects. Here we demonstrate that germline and post-natal targeted knockdown of the PYY3-36 preferring receptor (neuropeptide Y (NPY) Y2 receptor (Y2R)) in the afferent vagus nerve is required for the appetite inhibitory effects of physiologically-released PYY3-36, but not peripherally administered pharmacological doses. Post-natal knockdown of the Y2R results in a transient body weight phenotype that is not evident in the germline model. Loss of vagal Y2R signalling also results in altered meal patterning associated with accelerated gastric emptying. These results are important for the design of PYY-based anti-obesity agents.
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Affiliation(s)
- Aldara Martin Alonso
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Simon C Cork
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom; School of Medicine, Faculty of Health, Education, Medicine & Social Care, Anglia Ruskin University, Chelmsford, CM1 1SQ, United Kingdom
| | - Phyllis Phuah
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Benjamin Hansen
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Mariana Norton
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Sijing Cheng
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Xiang Xu
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Kinga Suba
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Yue Ma
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Georgina Kc Dowsett
- Medical Research Council Metabolic Diseases Unit, Wellcome-MRC Institute of Metabolic Science, University of Cambridge, United Kingdom
| | - John A Tadross
- Medical Research Council Metabolic Diseases Unit, Wellcome-MRC Institute of Metabolic Science, University of Cambridge, United Kingdom
| | - Brian Yh Lam
- Medical Research Council Metabolic Diseases Unit, Wellcome-MRC Institute of Metabolic Science, University of Cambridge, United Kingdom
| | - Giles Sh Yeo
- Medical Research Council Metabolic Diseases Unit, Wellcome-MRC Institute of Metabolic Science, University of Cambridge, United Kingdom
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, Darlinghurst, Australia
| | - Stephen R Bloom
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Myrtha Arnold
- Department of Health Sciences and Technology, ETH Zurich, Schwerzenbach, Switzerland
| | - Walter Distaso
- Imperial College Business School, Imperial College London, United Kingdom
| | - Kevin G Murphy
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Victoria Salem
- Section of Investigative Medicine and Endocrinology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom; Department of Bioengineering, Imperial College London, London, United Kingdom.
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Zhao Y, Peng X, Wang Q, Zhang Z, Wang L, Xu Y, Yang H, Bai J, Geng D. Crosstalk Between the Neuroendocrine System and Bone Homeostasis. Endocr Rev 2024; 45:95-124. [PMID: 37459436 DOI: 10.1210/endrev/bnad025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Indexed: 01/05/2024]
Abstract
The homeostasis of bone microenvironment is the foundation of bone health and comprises 2 concerted events: bone formation by osteoblasts and bone resorption by osteoclasts. In the early 21st century, leptin, an adipocytes-derived hormone, was found to affect bone homeostasis through hypothalamic relay and the sympathetic nervous system, involving neurotransmitters like serotonin and norepinephrine. This discovery has provided a new perspective regarding the synergistic effects of endocrine and nervous systems on skeletal homeostasis. Since then, more studies have been conducted, gradually uncovering the complex neuroendocrine regulation underlying bone homeostasis. Intriguingly, bone is also considered as an endocrine organ that can produce regulatory factors that in turn exert effects on neuroendocrine activities. After decades of exploration into bone regulation mechanisms, separate bioactive factors have been extensively investigated, whereas few studies have systematically shown a global view of bone homeostasis regulation. Therefore, we summarized the previously studied regulatory patterns from the nervous system and endocrine system to bone. This review will provide readers with a panoramic view of the intimate relationship between the neuroendocrine system and bone, compensating for the current understanding of the regulation patterns of bone homeostasis, and probably developing new therapeutic strategies for its related disorders.
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Affiliation(s)
- Yuhu Zhao
- Department of Orthopedics, The First Affiliated Hospital of Soochow University; Orthopedics Institute, Medical College, Soochow University, Suzhou, Jiangsu 215006, China
| | - Xiaole Peng
- Department of Orthopedics, The First Affiliated Hospital of Soochow University; Orthopedics Institute, Medical College, Soochow University, Suzhou, Jiangsu 215006, China
| | - Qing Wang
- Department of Orthopedics, The First Affiliated Hospital of Soochow University; Orthopedics Institute, Medical College, Soochow University, Suzhou, Jiangsu 215006, China
| | - Zhiyu Zhang
- Department of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, China
| | - Liangliang Wang
- Department of Orthopedics, The Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, China
| | - Yaozeng Xu
- Department of Orthopedics, The First Affiliated Hospital of Soochow University; Orthopedics Institute, Medical College, Soochow University, Suzhou, Jiangsu 215006, China
| | - Huilin Yang
- Department of Orthopedics, The First Affiliated Hospital of Soochow University; Orthopedics Institute, Medical College, Soochow University, Suzhou, Jiangsu 215006, China
| | - Jiaxiang Bai
- Department of Orthopedics, The First Affiliated Hospital of Soochow University; Orthopedics Institute, Medical College, Soochow University, Suzhou, Jiangsu 215006, China
- Department of Orthopedics, Division of Life Sciences and Medicine, The First Affiliated Hospital of USTC, University of Science and Technology of China, Hefei 230022, China
| | - Dechun Geng
- Department of Orthopedics, The First Affiliated Hospital of Soochow University; Orthopedics Institute, Medical College, Soochow University, Suzhou, Jiangsu 215006, China
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Qi Y, Lee NJ, Ip CK, Enriquez R, Tasan R, Zhang L, Herzog H. Agrp-negative arcuate NPY neurons drive feeding under positive energy balance via altering leptin responsiveness in POMC neurons. Cell Metab 2023:S1550-4131(23)00177-8. [PMID: 37201523 DOI: 10.1016/j.cmet.2023.04.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/14/2022] [Accepted: 04/26/2023] [Indexed: 05/20/2023]
Abstract
Neuropeptide Y (NPY) in the arcuate nucleus (ARC) is known as one of the most critical regulators of feeding. However, how NPY promotes feeding under obese conditions is unclear. Here, we show that positive energy balance, induced by high-fat diet (HFD) or in genetically obese leptin-receptor-deficient mice, leads to elevated Npy2r expression especially on proopiomelanocortin (POMC) neurons, which also alters leptin responsiveness. Circuit mapping identified a subset of ARC agouti-related peptide (Agrp)-negative NPY neurons that control these Npy2r expressing POMC neurons. Chemogenetic activation of this newly discovered circuitry strongly drives feeding, while optogenetic inhibition reduces feeding. Consistent with that, lack of Npy2r on POMC neurons leads to reduced food intake and fat mass. This suggests that under energy surplus conditions, when ARC NPY levels generally drop, high-affinity NPY2R on POMC neurons is still able to drive food intake and enhance obesity development via NPY released predominantly from Agrp-negative NPY neurons.
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Affiliation(s)
- Yue Qi
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - Nicola J Lee
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - Chi Kin Ip
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - Ronaldo Enriquez
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW 2010, Australia
| | - Ramon Tasan
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - Lei Zhang
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia.
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia.
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Malone IG, Hunter BK, Rossow HL, Herzog H, Zolotukhin S, Munger SD, Dotson CD. Y1 receptors modulate taste-related behavioral responsiveness in male mice to prototypical gustatory stimuli. Horm Behav 2021; 136:105056. [PMID: 34509673 PMCID: PMC8640844 DOI: 10.1016/j.yhbeh.2021.105056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 08/16/2021] [Accepted: 08/19/2021] [Indexed: 10/20/2022]
Abstract
Mammalian taste bud cells express receptors for numerous peptides implicated elsewhere in the body in the regulation of metabolism, nutrient assimilation, and satiety. The perturbation of several peptide signaling pathways in the gustatory periphery results in changes in behavioral and/or physiological responsiveness to subsets of taste stimuli. We previously showed that Peptide YY (PYY) - which is present in both saliva and in subsets of taste cells - can affect behavioral taste responsiveness and reduce food intake and body weight. Here, we investigated the contributions of taste bud-localized receptors for PYY and the related Neuropeptide Y (NPY) on behavioral taste responsiveness. Y1R, but not Y2R, null mice show reduced responsiveness to sweet, bitter, and salty taste stimuli in brief-access taste tests; similar results were seen when wildtype mice were exposed to Y receptor antagonists in the taste stimuli. Finally, mice in which the gene encoding the NPY propeptide was deleted also showed reduced taste responsiveness to sweet and bitter taste stimuli. Collectively, these results suggest that Y1R signaling, likely through its interactions with NPY, can modulate peripheral taste responsiveness in mice.
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Affiliation(s)
- Ian G Malone
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Brianna K Hunter
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Heidi L Rossow
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | | | - Sergei Zolotukhin
- Center for Smell and Taste, University of Florida, Gainesville, FL 32610, USA; Department of Pediatrics, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Steven D Munger
- Center for Smell and Taste, University of Florida, Gainesville, FL 32610, USA; Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, FL 32610, USA; Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Cedrick D Dotson
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA.
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Grossmann M, Fui MNT, Nie T, Hoermann R, Clarke MV, Cheung AS, Zajac JD, Davey RA. Changes in white adipose tissue gene expression in a randomized control trial of dieting obese men with lowered serum testosterone alone or in combination with testosterone treatment. Endocrine 2021; 73:463-471. [PMID: 33864607 DOI: 10.1007/s12020-021-02722-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 03/30/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE The aim of this study was to determine early weight loss-associated changes in subcutaneous abdominal white adipose tissue (WAT) gene expression in obese men with lowered serum testosterone by RNA next-generation sequencing. METHODS Fourteen men, mean age (IQR) 51.6 years (43.4-54.5), BMI 38.3 kg/m2 (34.6-40.8) and total testosterone 8.4 nmol/L (7.5-9.5) provided subcutaneous WAT samples at baseline and after 2 weeks of a very low energy diet. RESULTS Body weight loss was similar in participants receiving testosterone (n = 6), -5.27 kg [95% CI -6.17; -4.26], and placebo (n = 8), -4.57 kg [95% CI -6.10; -3.55], p = 0.86. In placebo-treated men, of the 14,410 genes expressed in subcutaneous WAT, four genes, Angiopoietin-like 4, Semaphorin 3 G, Neuropilin 2 and Angiopoietin 4, were upregulated (adjusted false discovery rate P < 0.05). In an exploratory analysis comparing men receiving testosterone and placebo, the most-upregulated gene in the testosterone group (exploratory p < 0.0005) was the neuropeptide y receptor 2. CONCLUSIONS In obese men, dieting is associated with upregulation of WAT-expressed Angiopoietin-like 4, a secreted protein that regulates lipid metabolism, Semaphorin 3 G, a proposed adipocyte differentiation factor and secreted adipokine, and its receptor Neuropilin 2, as well as Angiopoietin 4, a vascular integrity factor. In an exploratory analysis, testosterone was associated with the upregulation of neuropeptide y receptor 2, a receptor involved in appetite regulation. Further studies are needed to confirm these observations and their potential biological implications. TRIAL REGISTRATION clinicaltrials.gov, Identifier NCT01616732, Registration date: June 8, 2012.
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Affiliation(s)
- Mathis Grossmann
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Mark Ng Tang Fui
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Tian Nie
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Rudolf Hoermann
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Michele V Clarke
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Ada S Cheung
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Jeffrey D Zajac
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Rachel A Davey
- Department of Medicine Austin Health, University of Melbourne, Heidelberg, Victoria, Australia.
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Functional deletion of neuropeptide Y receptors type 2 in local synaptic networks of anteroventral BNST facilitates recall and increases return of fear. Mol Psychiatry 2021; 26:2900-2911. [PMID: 32709995 PMCID: PMC8505243 DOI: 10.1038/s41380-020-0846-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 07/06/2020] [Accepted: 07/13/2020] [Indexed: 12/14/2022]
Abstract
Return of previously extinguished fear memories presents a major hurdle in treatment of fear-related disorders. Neuropeptide Y receptors type 2 (Y2R) in the bed nucleus of stria terminalis (BNST) seem to play a crucial role in modulation of remote fear memories. Here, we targeted Cre-channelrhodopsin-2 to defined subregions of BNST or central amygdala (CeA) in floxed Y2R mice (Y2lox/lox) for functional deletion of Y2R. We combined fear training and behavioral studies in vivo with optogenetic-electrophysiological analysis of BNST synaptic network activity ex vivo, in order to identify regional and cellular specificities of Y2R influence. Deletion of Y2R in the ventral section of anterior BNST (BNSTav) did not affect fear acquisition, but increased conditioned fear during recall and extinction learning, and aggravated remote fear return. By contrast, deletion of Y2R in the dorsal section of anterior BNST (BNSTad) or CeA did not influence acquisition, extinction or return of fear memories. Ex vivo optogenetic-electrophysiological analysis revealed Y2R-expressing local GABAergic inhibitory networks in BNST, both within (intraregional) and in-between (inter-regional) BNST subregions. Stimulation of Y2R resulted in a presynaptically mediated reduction of GABAergic responses, which did not differ between intraregional but predominantly affected inter-regional connections from BNSTav to BNSTad. Moreover, deletion of Y2R decreased the excitation/inhibition balance in BNSTav neurons, suggesting a regulatory influence of endogenous NPY via intraregional GABAergic microcircuits. This study reveals Y2R within local GABAergic networks in BNST as key elements in facilitating extinction and reducing return of remote fear memories, suggesting a potential avenue for translational purposes.
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Sex differences in behavioral and metabolic effects of gene inactivation: The neuropeptide Y and Y receptors in the brain. Neurosci Biobehav Rev 2020; 119:333-347. [PMID: 33045245 DOI: 10.1016/j.neubiorev.2020.09.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 02/06/2023]
Abstract
Brain and gonadal hormones interplay controls metabolic and behavioral functions in a sex-related manner. However, most translational neuroscience research related to animal models of endocrine and psychiatric disorders are often carried out in male animals only. The Neuropeptide Y (NPY) system shows sex-dependent differences and is sensitive to gonadal steroids. Based on published data from our and other laboratories, in this review we will discuss the sex related differences of NPY action on energy balance, bone homeostasis and behavior in rodents with the genetic manipulation of genes encoding NPY and its Y1, Y2 and Y5 cognate receptors. Comparative analyses of the phenotype of transgenic and knockout NPY and Y receptor rodents unravels sex dependent differences in the functions of this neurotransmission system, potentially helping to develop therapeutics for a variety of sex-related disorders including metabolic syndrome, osteoporosis and ethanol addiction.
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Usefulness of a Kampo Medicine on Stress-Induced Delayed Gastric Emptying in Mice. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2020; 2020:3797219. [PMID: 32089720 PMCID: PMC7013301 DOI: 10.1155/2020/3797219] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 12/26/2019] [Indexed: 01/10/2023]
Abstract
Anxiety and depression often occur with gastrointestinal symptoms. Although the Japanese traditional medicine (Kampo medicine) bukuryoingohangekobokuto (BGH) is approved for treating anxiety, neurotic gastritis, and heartburn, its effect on gastrointestinal motility remains poorly known. This study aimed to examine the effect of BGH on delayed gastric emptying in stress model mice and clarified its action mechanism. Seven-week-old C57BL/6 male mice were acclimated for a week and fasted overnight. Stress hormone, corticotropin-releasing factor (CRF), was intracerebroventricularly injected to mice, and solid nutrient meal (ground chow and distilled water) was orally administered 1 hour after. Gastric contents were collected to evaluate gastric emptying rates by measuring its dry weight. Injection of CRF (0.3 or 1.0 μg/mouse) significantly delayed the 2-hour gastric emptying in mice. BGH (1.0 g/kg), which was administered 30 minutes before the CRF injection, significantly ameliorated the delayed gastric emptying induced by CRF (0.3 μg/mouse). BGH (0.5, 1.0 g/kg) significantly enhanced the 1-hour gastric emptying and slightly increased the 2-hour gastric emptying in mice without CRF injection. In vitro functional assays showed that components of BGH antagonized or inhibited CRF type-2, dopamine D2/D3, neuropeptide Y Y2 receptors, or acetylcholinesterase. In conclusion, the components of BGH may exert synergistic effects on improving gastric emptying via various targets. BGH is considered to be potentially useful for treating gastrointestinal dysmotility with psychological symptoms.
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Yuan D, Gao Y, Zhang X, Wang B, Chen H, Wu Y, Chen D, Wang Z, Li Z. NPY and NPY receptors in the central control of feeding and interactions with CART and MC4R in Siberian sturgeon. Gen Comp Endocrinol 2019; 284:113239. [PMID: 31394086 DOI: 10.1016/j.ygcen.2019.113239] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 07/25/2019] [Accepted: 08/04/2019] [Indexed: 01/08/2023]
Abstract
Neuropeptide Y (NPY) is the most powerful central neuropeptide implicated in feeding regulation via its receptors. Understanding the role of NPY system is critical to elucidate animal feeding regulation. Unlike mammal, the possible mechanisms of NPY system in the food intake of teleost fish are mostly unknown. Therefore, we investigated the regulatory mechanism of NPY and NPY receptors in Siberian sturgeon. In this study, we cloned the cDNA encoding NPY, and assessed the effects of different energy status on npy mRNAs abundance. The expression of npy was decreased in the brain after feeding 1 and 3 h. Besides, the expression of npy was increased after fasting within 15 days, while exhibiting significant decrease after refeeding. In order to further characterize the role of NPY receptor in fish, we performed acute intraperitoneal (i.p.) injection of NPY Y1 and Y2 receptor agonists, which is [Leu 31, Pro 34] NPY and NPY13-36 respectively. The results showed that the food intake of Siberian sturgeon was increased within 30 mins after injection of both Y1 and Y2 receptor agonist. To explore the relationship between NPY, NPY receptors and another appetite peptides, we examined the level of npy, cocaine- and amphetamine-regulated transcript (cart) and melanocortin-4 receptor (mc4r) by injected Y1 and Y2 receptor agonist. The results suggested that cart expression was regulated by NPY which acts on Y1 receptor or Y2 receptor. While mc4r expression just was mediated by NPY and Y1 receptor.
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Affiliation(s)
- Dengyue Yuan
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China; Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Science, Southwest University, Chongqing 400715, China
| | - Yundi Gao
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Xin Zhang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Bin Wang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Hu Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Yuanbing Wu
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Defang Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Zhijian Wang
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Science, Southwest University, Chongqing 400715, China
| | - Zhiqiong Li
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China.
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Islam R, Prater CM, Harris BN, Carr JA. Neuroendocrine modulation of predator avoidance/prey capture tradeoffs: Role of tectal NPY2R receptors. Gen Comp Endocrinol 2019; 282:113214. [PMID: 31271760 DOI: 10.1016/j.ygcen.2019.113214] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/28/2019] [Accepted: 06/29/2019] [Indexed: 12/16/2022]
Abstract
The optic tectum rapidly inhibits food intake when a visual threat is present. Anatomical and electrophysiological evidence support a role for neuropeptide Y (NPY), originating from cells in the thalamus, in the tectal inhibition of prey capture. Here we test the hypothesis that tectal NPY receptor type 2 (NPY2R) influences prey-capture and predator-avoidance responses in the African clawed frog, Xenopus laevis. We tested two questions: 1) Does tectal NPY administration decrease food intake and alter prey-capture behavior? 2) Does tectal administration of a NPY2R antagonist increase food intake, alter prey-capture behavior, and alter predator avoidance behavior? NPY microinjected bilaterally into the tecta failed to significantly alter food intake at any dose tested, although predator presence significantly reduced food intake. However, NPY differentially altered discrete components of prey capture including increasing the latency to contact food and reducing the amount of time in contact with food. These effects were blocked by the NPY2R antagonist BIIE0246. Additionally, BIIE0246 elevated food intake on its own after bilateral tectal microinjection. Furthermore, BIIE0246 reversed the reduction of food intake caused by exposure to a predator. Overall, these findings indicate that tectal NPY2R activation causes frogs to consume food more quickly, which may be adaptive in predator-rich environments. Blocking tectal NPY2R increases baseline food intake and reduces or eliminates predator-induced changes in prey capture and food intake.
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Affiliation(s)
- Ranakul Islam
- Department of Biological Sciences, Texas Tech University, United States
| | | | - Breanna N Harris
- Department of Biological Sciences, Texas Tech University, United States
| | - James A Carr
- Department of Biological Sciences, Texas Tech University, United States.
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11
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Guo DF, Lin Z, Wu Y, Searby C, Thedens DR, Richerson GB, Usachev YM, Grobe JL, Sheffield VC, Rahmouni K. The BBSome in POMC and AgRP Neurons Is Necessary for Body Weight Regulation and Sorting of Metabolic Receptors. Diabetes 2019; 68:1591-1603. [PMID: 31127052 PMCID: PMC6692817 DOI: 10.2337/db18-1088] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 05/12/2019] [Indexed: 12/22/2022]
Abstract
The BBSome, a complex of eight Bardet-Biedl syndrome (BBS) proteins involved in cilia function, has emerged as an important regulator of energy balance, but the underlying cellular and molecular mechanisms are not fully understood. Here, we show that the control of energy homeostasis by the anorexigenic proopiomelanocortin (POMC) neurons and orexigenic agouti-related peptide (AgRP) neurons require intact BBSome. Targeted disruption of the BBSome by Bbs1 gene deletion in POMC or AgRP neurons increases body weight and adiposity. We demonstrate that obesity in mice lacking the Bbs1 gene in POMC neurons is associated with hyperphagia. Mechanistically, we present evidence implicating the BBSome in the trafficking of G protein-coupled neuropeptide Y Y2 receptor (NPY2R) and serotonin 5-hydroxytryptamine (HT)2C receptor (5-HT2CR) to cilia and plasma membrane, respectively. Consistent with this, loss of the BBSome reduced cell surface expression of the 5-HT2CR, interfered with serotonin-evoked increase in intracellular calcium and membrane potential, and blunted the anorectic and weight-reducing responses evoked by the 5-HT2cR agonist, lorcaserin. Finally, we show that disruption of the BBSome causes the 5-HT2CR to be stalled in the late endosome. Our results demonstrate the significance of the hypothalamic BBSome for the control of energy balance through regulation of trafficking of important metabolic receptors.
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Affiliation(s)
- Deng-Fu Guo
- Department of Pharmacology, University of Iowa, Iowa City, IA
| | - Zhihong Lin
- Department of Pharmacology, University of Iowa, Iowa City, IA
| | - Yuanming Wu
- Department of Neurology, University of Iowa, Iowa City, IA
| | - Charles Searby
- Department of Pediatrics, University of Iowa, Iowa City, IA
| | | | | | - Yuriy M Usachev
- Department of Pharmacology, University of Iowa, Iowa City, IA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA
| | - Justin L Grobe
- Department of Pharmacology, University of Iowa, Iowa City, IA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA
- Obesity Education and Research Initiative, University of Iowa, Iowa City, IA
| | - Val C Sheffield
- Department of Pediatrics, University of Iowa, Iowa City, IA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA
- Obesity Education and Research Initiative, University of Iowa, Iowa City, IA
| | - Kamal Rahmouni
- Department of Pharmacology, University of Iowa, Iowa City, IA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA
- Obesity Education and Research Initiative, University of Iowa, Iowa City, IA
- Department of Internal Medicine, University of Iowa, Iowa City, IA
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12
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GABAergic Inputs to POMC Neurons Originating from the Dorsomedial Hypothalamus Are Regulated by Energy State. J Neurosci 2019; 39:6449-6459. [PMID: 31235650 DOI: 10.1523/jneurosci.3193-18.2019] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/21/2019] [Accepted: 06/10/2019] [Indexed: 02/06/2023] Open
Abstract
Neuronal circuits regulating hunger and satiety synthesize information encoding the energy state of the animal and translate those signals into motivated behaviors to meet homeostatic needs. Proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus are activated by energy surfeits and inhibited by energy deficits. When activated, these cells inhibit food intake and facilitate weight loss. Conversely, decreased activity in POMC cells is associated with increased food intake and obesity. Circulating nutrients and hormones modulate the activity of POMC neurons over protracted periods of time. However, recent work indicates that calcium activity in POMC cells changes in response to food cues on times scales consistent with the rapid actions of amino acid transmitters. Indeed, the frequency of spontaneous IPSCs (sIPSCs) onto POMC neurons increases during caloric deficits. However, the afferent brain regions responsible for this inhibitory modulation are currently unknown. Here, through the use of brain region-specific deletion of GABA release in both male and female mice we show that neurons in the dorsomedial hypothalamus (DMH) are responsible for the majority of sIPSCs in POMC neurons as well as the fasting-induced increase in sIPSC frequency. Further, the readily releasable pool of GABA vesicles and the release probability of GABA is increased at DMH-to-POMC synapses following an overnight fast. Collectively these data provide evidence that DMH-to-POMC GABA circuitry conveys inhibitory neuromodulation onto POMC cells that is sensitive to the animal's energy state.SIGNIFICANCE STATEMENT Activation of proopiomelanocortin (POMC) cells signals satiety, whereas GABAergic cells in the dorsomedial hypothalamus (DMH) can increase food consumption. However, communication between these cells, particularly in response to changes in metabolic state, is unknown. Here, through targeted inhibition of DMH GABA release, we show that DMH neurons contribute a significant portion of spontaneously released GABA onto POMC cells and are responsible for increased GABAergic inhibition of POMC cells during fasting, likely mediated through increased release probability of GABA at DMH terminals. These data provide important information about inhibitory modulation of metabolic circuitry and provide a mechanism through which POMC neurons could be inhibited, or disinhibited, rapidly in response to food availability.
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13
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An ATF3-CreERT2 Knock-In Mouse for Axotomy-Induced Genetic Editing: Proof of Principle. eNeuro 2019; 6:eN-MNT-0025-19. [PMID: 30993183 PMCID: PMC6464513 DOI: 10.1523/eneuro.0025-19.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 03/18/2019] [Accepted: 03/20/2019] [Indexed: 01/08/2023] Open
Abstract
Genome editing techniques have facilitated significant advances in our understanding of fundamental biological processes, and the Cre-Lox system has been instrumental in these achievements. Driving Cre expression specifically in injured neurons has not been previously possible: we sought to address this limitation in mice using a Cre-ERT2 construct driven by a reliable indicator of axotomy, activating transcription factor 3 (ATF3). When crossed with reporter mice, a significant amount of recombination was achieved (without tamoxifen treatment) in peripherally-projecting sensory, sympathetic, and motoneurons after peripheral nerve crush in hemizygotes (65–80% by 16 d) and was absent in uninjured neurons. Importantly, injury-induced recombination did not occur in Schwann cells distal to the injury, and with a knock-out-validated antibody we verified an absence of ATF3 expression. Functional recovery following sciatic nerve crush in ATF3-deficient mice (both hemizygotes and homozygotes) was delayed, indicating previously unreported haploinsufficiency. In a proof-of-principle experiment, we crossed the ATF3-CreERT2 line with a floxed phosphatase and tensin homolog (PTEN) line and show significantly improved axonal regeneration, as well as more complete recovery of neuromuscular function. We also demonstrate the utility of the ATF3-CreERT2 hemizygous line by characterizing recombination after lateral spinal hemisection (C8/T1), which identified specific populations of ascending spinal cord neurons (including putative spinothalamic and spinocerebellar) and descending supraspinal neurons (rubrospinal, vestibulospinal, reticulospinal and hypothalamic). We anticipate these mice will be valuable in distinguishing axotomized from uninjured neurons of several different classes (e.g., via reporter expression), and in probing the function of any number of genes as they relate to neuronal injury and regeneration.
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14
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Boland B, Mumphrey MB, Hao Z, Gill B, Townsend RL, Yu S, Münzberg H, Morrison CD, Trevaskis JL, Berthoud HR. The PYY/Y2R-Deficient Mouse Responds Normally to High-Fat Diet and Gastric Bypass Surgery. Nutrients 2019; 11:E585. [PMID: 30857366 PMCID: PMC6471341 DOI: 10.3390/nu11030585] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND/GOALS The gut hormone peptide YY (PYY) secreted from intestinal L-cells has been implicated in the mechanisms of satiation via Y2-receptor (Y2R) signaling in the brain and periphery and is a major candidate for mediating the beneficial effects of bariatric surgery on appetite and body weight. METHODS Here we assessed the role of Y2R signaling in the response to low- and high-fat diets and its role in the effects of Roux-en-Y gastric bypass (RYGB) surgery on body weight, body composition, food intake, energy expenditure and glucose handling, in global Y2R-deficient (Y2RKO) and wildtype (WT) mice made obese on high-fat diet. RESULTS Both male and female Y2RKO mice responded normally to low- and high-fat diet in terms of body weight, body composition, fasting levels of glucose and insulin, as well as glucose and insulin tolerance for up to 30 weeks of age. Contrary to expectations, obese Y2RKO mice also responded similarly to RYGB compared to WT mice for up to 20 weeks after surgery, with initial hypophagia, sustained body weight loss, and significant improvements in fasting insulin, glucose tolerance, insulin resistance (HOMA-IR), and liver weight compared to sham-operated mice. Furthermore, non-surgical Y2RKO mice weight-matched to RYGB showed the same improvements in glycemic control as Y2RKO mice with RYGB that were similar to WT mice. CONCLUSIONS PYY signaling through Y2R is not required for the normal appetite-suppressing and body weight-lowering effects of RYGB in this global knockout mouse model. Potential compensatory adaptations of PYY signaling through other receptor subtypes or other gut satiety hormones such as glucagon-like peptide-1 (GLP-1) remain to be investigated.
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Affiliation(s)
- Brandon Boland
- Cardiovascular, Renal & Metabolic Diseases, MedImmune, Gaithersburg, MD 20878, USA.
| | - Michael B Mumphrey
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
| | - Zheng Hao
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
| | - Benji Gill
- Cardiovascular, Renal & Metabolic Diseases, MedImmune, Gaithersburg, MD 20878, USA.
| | - R Leigh Townsend
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
| | - Sangho Yu
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
| | - Heike Münzberg
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
| | - Christopher D Morrison
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
| | - James L Trevaskis
- Cardiovascular, Renal & Metabolic Diseases, MedImmune, Gaithersburg, MD 20878, USA.
| | - Hans-Rudolf Berthoud
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
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15
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Lee NJ, Clarke IM, Zengin A, Enriquez RF, Nagy V, Penninger JM, Baldock PA, Herzog H. RANK deletion in neuropeptide Y neurones attenuates oestrogen deficiency-related bone loss. J Neuroendocrinol 2019; 31:e12687. [PMID: 30633834 DOI: 10.1111/jne.12687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/06/2019] [Accepted: 01/07/2019] [Indexed: 12/17/2022]
Abstract
The RANKL pathway is known to be an important aspect of the pathogenesis of oestrogen deficiency-induced bone loss. RANK deletion specifically in neuropeptide Y (NPY) neurones has been shown to enhance the ability of the skeleton to match increases in body weight caused by high-fat diet feeding, likely via the modulation of NPY levels. In the present study, we used ovariectomy in female mice to show that RANK deletion in NPY neurones attenuates bone loss caused by long-term oestrogen deficiency, particularly in the vertebral compartment. Ovariectomy led to a reduction in NPY expression levels in the arcuate nucleus of NPYcre/+ ;RANKlox/lox mice compared to NPYcre/+ ;RANKlox/+ controls. Because NPY deficient mice also displayed a similar protection against ovariectomy-induced bone loss, modulation of hypothalamic NPY signalling is the likely mechanism behind the protection from bone loss in the NPYcre/+ ;RANKlox/lox mice.
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Affiliation(s)
- Nicola J Lee
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
- St Vincents Clinical School, UNSW Sydney, Sydney, New South Wales, Australia
| | - Ireni M Clarke
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
| | - Ayse Zengin
- Bone Biology Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
| | - Ronaldo F Enriquez
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
- Bone Biology Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
| | - Vanj Nagy
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Josef M Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - Paul A Baldock
- St Vincents Clinical School, UNSW Sydney, Sydney, New South Wales, Australia
- Bone Biology Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
- St Vincents Clinical School, UNSW Sydney, Sydney, New South Wales, Australia
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16
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Lee NJ, Clarke IM, Enriquez RF, Nagy V, Penninger J, Baldock PA, Herzog H. Central RANK signalling in NPY neurons alters bone mass in male mice. Neuropeptides 2018; 68:75-83. [PMID: 29477253 DOI: 10.1016/j.npep.2018.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 02/05/2018] [Accepted: 02/14/2018] [Indexed: 11/23/2022]
Abstract
RANKL signalling known to be important for the control of bone mass, has recently also been implicated in the brain to control thermoregulation, however, it is not known which neuronal pathways are involved and whether other aspects of energy homeostasis are also affected. Here we show that selective deletion of RANK from NPY neurons down-regulated NPY mRNA expression in the hypothalamus. While comprehensive phenotyping of germline-induced NPY neuron specific RANK deficient mice revealed no significant changes in physical or metabolic parameters, adult onset deletion of RANK from NPY neurons led to a significant increase in fat mass and a decrease in whole body bone mineral content and bone mineral density. Intriguingly, when these conditional knockout mice were placed on a high fat diet, body weight and fat mass did not differ to control mice. However, they were able to significantly increase their bone mass to match their increased body weight, an ability that was lacking in control mice. Taken together, results from this study demonstrate that RANK signalling in NPY neurons is involved in modulating NPY levels and through that matching bone mass to body weight.
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Affiliation(s)
- N J Lee
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, NSW, Australia; St Vincents Clinical School, UNSW Sydney, Sydney, NSW, Australia.
| | - I M Clarke
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - R F Enriquez
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, NSW, Australia; St Vincents Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - V Nagy
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), 1030 Vienna, Austria
| | - J Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), 1030 Vienna, Austria
| | - P A Baldock
- Bone Biology Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, NSW, Australia; St Vincents Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - H Herzog
- Neuroscience Division, Garvan Institute, St Vincent's Hospital, Darlinghurst, NSW, Australia; St Vincents Clinical School, UNSW Sydney, Sydney, NSW, Australia
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17
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Seldeen KL, Halley PG, Volmar CH, Rodríguez MA, Hernandez M, Pang M, Carlsson SK, Suva LJ, Wahlestedt C, Troen BR, Brothers SP. Neuropeptide Y Y2 antagonist treated ovariectomized mice exhibit greater bone mineral density. Neuropeptides 2018; 67:45-55. [PMID: 29129406 PMCID: PMC5805636 DOI: 10.1016/j.npep.2017.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 11/06/2017] [Accepted: 11/06/2017] [Indexed: 12/15/2022]
Abstract
Osteoporosis, a disease characterized by progressive bone loss and increased risk of fracture, often results from menopausal loss of estrogen in women. Neuropeptide Y has been shown to negatively regulate bone formation, with amygdala specific deletion of the Y2 receptor resulting in increased bone mass in mice. In this study, ovariectomized (OVX) mice were injected once daily with JNJ-31020028, a brain penetrant Y2 receptor small molecule antagonist to determine the effects on bone formation. Antagonist treated mice had reduced weight and showed increased whole-body bone mineral density compared to vehicle-injected mice. Micro computerized tomography (micro-CT) demonstrated increased vertebral trabecular bone volume, connectivity density and trabecular thickness. Femoral micro-CT analysis revealed increased bone volume within trabecular regions and greater trabecular number, without significant difference in other parameters or within cortical regions. A decrease was seen in serum P1NP, a measure used to confirm positive treatment outcomes in bisphosphonate treated patients. C-terminal telopeptide 1 (CTX-1), a blood biomarker of bone resorption, was decreased in treated animals. The higher bone mineral density observed following Y2 antagonist treatment, as determined by whole-body DEXA scanning, is indicative of either enhanced mineralization or reduced bone loss. Additionally, our findings that ex vivo treatment of bone marrow cells with the Y2 antagonist did not affect osteoblast and osteoclast formation suggests the inhibitor is not affecting these cells directly, and suggests a central role for compound action in this system. Our results support the involvement of Y2R signalling in bone metabolism and give credence to the hypothesis that selective pharmacological manipulation of Y2R may provide anabolic benefits for treating osteoporosis.
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Affiliation(s)
- K L Seldeen
- Division of Geriatrics and Palliative Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA; Research Service, Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA
| | - P G Halley
- Center for Therapeutic Innovation, Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - C H Volmar
- Center for Therapeutic Innovation, Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - M A Rodríguez
- Bruce W. Carter VA Geriatric Research Education and Clinical Center (GRECC), Miami, FL, USA; University of Miami Miller School of Medicine, Miami, FL, USA
| | - M Hernandez
- Bruce W. Carter VA Geriatric Research Education and Clinical Center (GRECC), Miami, FL, USA; University of Miami Miller School of Medicine, Miami, FL, USA
| | - M Pang
- Division of Geriatrics and Palliative Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA; Research Service, Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA
| | - S K Carlsson
- Center for Therapeutic Innovation, Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - L J Suva
- Department of Orthopaedic Surgery, Centre for Orthopaedic Research, University of Arkansas Medical School, Little Rock, AR, USA
| | - C Wahlestedt
- Center for Therapeutic Innovation, Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - B R Troen
- Division of Geriatrics and Palliative Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA; Research Service, Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA
| | - S P Brothers
- Center for Therapeutic Innovation, Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA.
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18
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Wu Q, Han Y, Tong Q. Current Genetic Techniques in Neural Circuit Control of Feeding and Energy Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1090:211-233. [PMID: 30390293 DOI: 10.1007/978-981-13-1286-1_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The current epidemic of obesity and its associated metabolic syndromes imposes unprecedented challenges to our society. Despite intensive research focus on obesity pathogenesis, an effective therapeutic strategy to treat and cure obesity is still lacking. The obesity development is due to a disturbed homeostatic control of feeding and energy expenditure, both of which are controlled by an intricate neural network in the brain. Given the inherent complexity of brain networks in controlling feeding and energy expenditure, the understanding of brain-based pathophysiology for obesity development is limited. One key limiting factor in dissecting neural pathways for feeding and energy expenditure is unavailability of techniques that can be used to effectively reduce the complexity of the brain network to a tractable paradigm, based on which a strong hypothesis can be tested. Excitingly, emerging techniques have been involved to be able to link specific groups of neurons and neural pathways to behaviors (i.e., feeding and energy expenditure). In this chapter, novel techniques especially those based on animal models and viral vector approaches will be discussed. We hope that this chapter will provide readers with a basis that can help to understand the literatures using these techniques and with a guide to apply these exciting techniques to investigate brain mechanisms underlying feeding and energy expenditure.
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Affiliation(s)
- Qi Wu
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA. .,Children's Nutrition Research Center, Research Service of Department of Agriculture of USA, Houston, TX, USA.
| | - Yong Han
- Department of Pediatrics, Baylor College of Medicine, USDA-ARS, Houston, TX, USA
| | - Qingchun Tong
- Center for Metabolic and Degenerative Diseases, Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, USA.
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19
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Nishizawa N, Niida A, Adachi Y, Kanematsu-Yamaki Y, Masuda Y, Kumano S, Yokoyama K, Noguchi Y, Asakawa T, Hirabayashi H, Amano N, Takekawa S, Ohtaki T, Asami T. Highly potent antiobesity effect of a short-length peptide YY analog in mice. Bioorg Med Chem 2017; 25:5718-5725. [DOI: 10.1016/j.bmc.2017.08.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 08/26/2017] [Accepted: 08/27/2017] [Indexed: 01/07/2023]
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20
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Qi Y, Purtell L, Fu M, Zhang L, Zolotukhin S, Campbell L, Herzog H. Hypothalamus Specific Re-Introduction of SNORD116 into Otherwise Snord116 Deficient Mice Increased Energy Expenditure. J Neuroendocrinol 2017; 29. [PMID: 28094877 DOI: 10.1111/jne.12457] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 12/21/2016] [Accepted: 01/11/2017] [Indexed: 02/02/2023]
Abstract
The Snord116 gene cluster has been recognised as a critical contributor to the Prader-Willi syndrome (PWS), with mice lacking Snord116 displaying many classical PWS phenotypes, including low postnatal body weight, reduced bone mass and increased food intake. However, these mice do not develop obesity as a result of increased energy expenditure. To understand the physiological function of SNORD116 better and potentially rescue the altered metabolism of Snord116-/- mice, we used an adeno-associated viral (AAV) approach to reintroduce the product of the Snord116 gene into the hypothalamus in Snord116-/- mice at different ages. The results obtained show that mid-hypothalamic re-introduction of SNORD116 in 6-week-old Snord116-/- mice leads to significantly reduced body weight and weight gain, which is associated with elevated energy expenditure. Importantly, when the intervention targets other areas such as the anterior region of the hypothalamus or the reintroduction occurs in older mice, the positive effects on energy expenditure are diminished. These data indicate that the metabolic symptoms of PWS develop gradually and the Snord116 gene plays a critical role during this process. Furthermore, when we investigated the consequences of SNORD116 re-introduction under conditions of thermoneutrality where the mild cold stress influences are avoided, we also observed a significant increase in energy expenditure. In conclusion, the rescue of mid-hypothalamic Snord116 deficiency in young Snord116 germline deletion mice increases energy expenditure, providing fundamental information contributing to potential virus-mediated genetic therapy in PWS.
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Affiliation(s)
- Y Qi
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - L Purtell
- Diabetes Division, Garvan Institute of Medical Research, Sydney, Australia
| | - M Fu
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - L Zhang
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - S Zolotukhin
- Department of Pediatrics, College of Medicine, Center for Smell and Taste, University of Florida, Gainesville, FL, USA
| | - L Campbell
- Diabetes Division, Garvan Institute of Medical Research, Sydney, Australia
| | - H Herzog
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
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21
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Aerts E, Geets E, Sorber L, Beckers S, Verrijken A, Massa G, Hoorenbeeck K, Verhulst SL, Gaal LF, Hul W. Evaluation of a Role for
NPY
and
NPY2R
in the Pathogenesis of Obesity by Mutation and Copy Number Variation Analysis in Obese Children and Adolescents. Ann Hum Genet 2017; 82:1-10. [DOI: 10.1111/ahg.12211] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 07/26/2017] [Accepted: 07/28/2017] [Indexed: 11/26/2022]
Affiliation(s)
- Evi Aerts
- Department of Medical Genetics University of Antwerp Antwerp Belgium
| | - Ellen Geets
- Department of Medical Genetics University of Antwerp Antwerp Belgium
| | - Laure Sorber
- Department of Medical Genetics University of Antwerp Antwerp Belgium
| | - Sigri Beckers
- Department of Medical Genetics University of Antwerp Antwerp Belgium
| | - An Verrijken
- Department of Endocrinology, Diabetology and Metabolic Diseases Antwerp University Hospital Antwerp Belgium
| | - Guy Massa
- Department of Pediatrics Jessa Hospital Hasselt Belgium
| | - Kim Hoorenbeeck
- Department of Pediatrics Antwerp University Hospital Antwerp Belgium
| | - Stijn L Verhulst
- Department of Pediatrics Antwerp University Hospital Antwerp Belgium
| | - Luc F Gaal
- Department of Endocrinology, Diabetology and Metabolic Diseases Antwerp University Hospital Antwerp Belgium
| | - Wim Hul
- Department of Medical Genetics University of Antwerp Antwerp Belgium
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22
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Miller GD. Appetite Regulation: Hormones, Peptides, and Neurotransmitters and Their Role in Obesity. Am J Lifestyle Med 2017; 13:586-601. [PMID: 31662725 DOI: 10.1177/1559827617716376] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 05/18/2017] [Accepted: 05/31/2017] [Indexed: 12/29/2022] Open
Abstract
Understanding body weight regulation will aid in the development of new strategies to combat obesity. This review examines energy homeostasis and food intake behaviors, specifically with regards to hormones, peptides, and neurotransmitters in the periphery and central nervous system, and their potential role in obesity. Dysfunction in feeding signals by the brain is a factor in obesity. The hypothalamic (arcuate nucleus) and brainstem (nucleus tractus solitaris) areas integrate behavioral, endocrine, and autonomic responses via afferent and efferent pathways from and to the brainstem and peripheral organs. Neurons present in the arcuate nucleus express pro-opiomelanocortin, Neuropeptide Y, and Agouti Related Peptide, with the former involved in lowering food intake, and the latter two acutely increasing feeding behaviors. Action of peripheral hormones from the gut, pancreas, adipose, and liver are also involved in energy homeostasis. Vagal afferent neurons are also important in regulating energy homeostasis. Peripheral signals respond to the level of stored and currently available fuel. By studying their actions, new agents maybe developed that disable orexigenic responses and enhance anorexigenic signals. Although there are relatively few medications currently available for obesity treatment, a number of agents are in development that work through these pathways.
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Affiliation(s)
- Gary D Miller
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, North Carolina
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Nishizawa N, Niida A, Masuda Y, Kumano S, Yokoyama K, Hirabayashi H, Amano N, Ohtaki T, Asami T. A Short-Length Peptide YY Analogue with Anorectic Effect in Mice. ACS OMEGA 2017; 2:2200-2207. [PMID: 30023658 PMCID: PMC6044503 DOI: 10.1021/acsomega.7b00258] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 05/08/2017] [Indexed: 06/08/2023]
Abstract
Peripheral administration of PYY3-36, a fragment of peptide YY (PYY), has been reported to reduce food intake by activating the neuropeptide Y2 receptor (Y2R). An N-terminally truncated PYY analogue, benzoyl-[Ala26,Ile28,31]PYY(25-36) (1), showed a relatively potent agonist activity for Y2R but a weak anorectic activity by intraperitoneal administration (2000 nmol/kg) in lean mice because of its markedly poor biological stability in the mouse serum. Notably, two cyclohexylalanine (Cha) substitutions for Tyr residues at positions 27 and 36 (4) improved the stability in the mouse serum concomitant with enhanced anorectic activity. Further optimization at positions 27, 28, 30, and 31 revealed that 21, containing Cha28 and Aib31 residues, showed a more potent anorectic activity than PYY3-36 at a low dose of 300 nmol/kg. The minimum effective dose by intraperitoneal administration of 21 was 30 nmol/kg (ca. 52 μg/kg) in mice, suggesting the biologic potential of short-length PYY3-36 analogues with a potent anorectic effect.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Taiji Asami
- E-mail: . Phone: +81-466-32-1186. Fax: +81-466-29-4453
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Abstract
Obesity is a global epidemic that contributes to a number of health complications including cardiovascular disease, type 2 diabetes, cancer and neuropsychiatric disorders. Pharmacotherapeutic strategies to treat obesity are urgently needed. Research over the past two decades has increased substantially our knowledge of central and peripheral mechanisms underlying homeostatic energy balance. Homeostatic mechanisms involve multiple components including neuronal circuits, some originating in hypothalamus and brain stem, as well as peripherally-derived satiety, hunger and adiposity signals that modulate neural activity and regulate eating behavior. Dysregulation of one or more of these homeostatic components results in obesity. Coincident with obesity, reward mechanisms that regulate hedonic aspects of food intake override the homeostatic regulation of eating. In addition to functional interactions between homeostatic and reward systems in the regulation of food intake, homeostatic signals have the ability to alter vulnerability to drug abuse. Regarding the treatment of obesity, pharmacological monotherapies primarily focus on a single protein target. FDA-approved monotherapy options include phentermine (Adipex-P®), orlistat (Xenical®), lorcaserin (Belviq®) and liraglutide (Saxenda®). However, monotherapies have limited efficacy, in part due to the recruitment of alternate and counter-regulatory pathways. Consequently, a multi-target approach may provide greater benefit. Recently, two combination products have been approved by the FDA to treat obesity, including phentermine/topiramate (Qsymia®) and naltrexone/bupropion (Contrave®). The current review provides an overview of homeostatic and reward mechanisms that regulate energy balance, potential therapeutic targets for obesity and current treatment options, including some candidate therapeutics in clinical development. Finally, challenges in anti-obesity drug development are discussed.
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Affiliation(s)
- Vidya Narayanaswami
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536, USA
| | - Linda P Dwoskin
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536, USA.
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Qi Y, Purtell L, Fu M, Sengmany K, Loh K, Zhang L, Zolotukhin S, Sainsbury A, Campbell L, Herzog H. Ambient temperature modulates the effects of the Prader-Willi syndrome candidate gene Snord116 on energy homeostasis. Neuropeptides 2017; 61:87-93. [PMID: 27823858 DOI: 10.1016/j.npep.2016.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 10/18/2016] [Accepted: 10/24/2016] [Indexed: 02/05/2023]
Abstract
Germline deletion of the Prader-Willi syndrome (PWS) candidate gene Snord116 in mice leads to some classical symptoms of human PWS, notably reductions in body weight, linear growth and bone mass. However, Snord116 deficient mice (Snord116-/-) do not develop an obese phenotype despite their increased food intake and the underlying mechanism for that is unknown. We tested the phenotypes of germline Snord116-/- as well as neuropeptide Y (NPY) neuron specific Snord116lox/lox/NPYcre/+ mice at 30°C, the thermoneutral temperature of mice, and compared these to previous reports studies conducted at normal room temperature. Snord116-/- mice at 30°C still weighed less than wild type but had increased body weight gain. Importantly, food intake and energy expenditure were no longer different at 30°C, and the reduced bone mass and nasal-anal length observed in Snord116-/- mice at room temperature were also normalized. Mechanistically, the thermoneutral condition led to the correction of the mRNA expression of NPY and pro-opiomelanocortin (POMC), which were both previously observed to be significantly up-regulated at room temperature. Importantly, almost identical phenotypes and NPY/POMC mRNA expression alterations were also observed in Snord116lox/lox/NPYcre/+ mice, which lack the Snord116 gene only in NPY neurons. These data illustrate that mild cold stress is a critical factor preventing the development of obesity in Snord116-/- mice via the NPY system. Our study highlights that the function of Snord116 in the hypothalamus may be to enhance energy expenditure, likely via the NPY system, and also indicates that Snord116 function in mice is strongly dependent on environmental conditions such as cold exposure.
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Affiliation(s)
- Y Qi
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia.
| | - L Purtell
- Diabetes & Metabolism Division, Garvan Institute of Medical Research, Sydney, Australia
| | - M Fu
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - K Sengmany
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - K Loh
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - L Zhang
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - S Zolotukhin
- Department of Pediatrics, College of Medicine, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, USA
| | - A Sainsbury
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
| | - L Campbell
- Diabetes & Metabolism Division, Garvan Institute of Medical Research, Sydney, Australia
| | - H Herzog
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, Australia
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Alasvand M, Javanmard SH, Rashidi B, Khazaei M. Myocardial capillary density after neuropeptide Y antagonist administration in normal and high-fat diet C57BL6 mice. Adv Biomed Res 2016; 5:165. [PMID: 27995104 PMCID: PMC5137228 DOI: 10.4103/2277-9175.190998] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Accepted: 02/15/2016] [Indexed: 12/17/2022] Open
Abstract
Background: Neuropeptide Y (NPY), a 36 amino acid peptide, has several effects on cardiovascular system. It is demonstrated that the angiogenic activity of NPY is similar to fibroblast growth factor and vascular endothelial growth factor (VEGF). The aim of this study was to evaluate the effect of systemic administration of antagonist of NPY receptor (BIIE0742) on coronary angiogenesis in normal and diet-induced obese animals. Materials and Methods: Twenty-four male mice were received high-fat diet (HFD) or normal diet (ND) for 14 weeks. Then, each group was randomized to the treatment of antagonist of NPY receptor (BIIE0246) or saline as following: ND+ BIIE0246 (100 μl/kg; i.p.), ND+ saline, HFD+ BIIE0246, HFD+ saline. After 14 days, blood samples were taken, and myocardial tissue (left ventricle) from all experimental groups was evaluated by immunohistochemistry. Results: Serum VEGF concentration and VEGF: Soluble VEGF receptor (sVEGFR)-1 ratio in obese animals was higher than normal group. Administration of BIIE0246 significantly reduced serum VEGF and VEGF: sVEGFR-1 ratio and increased serum sVEGFR-1 concentrations in obese animals (P < 0.05). In normal animals, BIIE0246 increased serum sVEGFR-1 level and decreased VEGF: sVEGFR-1 ratio. Serum nitrite did not alter after administration of BIIE0246 in both groups (P > 0.05). Myocardial capillary density expressed as the number of CD31 positive cells/mm2 was reduced after NPY antagonist treatment in obese and normal animals (P > 0.05). Conclusion: Administration of NPY antagonist impairs myocardial capillary density, reduces angiogenic factors and elevates anti-angiogenic factors, and there are no differences between obese and normal animals.
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Affiliation(s)
- Masoud Alasvand
- Department of Physiology, Sanandaj University of Medical Sciences, Sanandaj, Iran
| | | | - Bahman Rashidi
- Department of Anatomy, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Majid Khazaei
- Neurogenic Inflammatory Research Center and Department of Physiology, Mashhad University of Medical Sciences, Mashhad, Iran
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Volta F, Gerdes JM. The role of primary cilia in obesity and diabetes. Ann N Y Acad Sci 2016; 1391:71-84. [DOI: 10.1111/nyas.13216] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 07/19/2016] [Accepted: 08/01/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Francesco Volta
- Institute for Diabetes and Regeneration Research; Helmholtz Zentrum München; Garching Germany
| | - Jantje M. Gerdes
- Institute for Diabetes and Regeneration Research; Helmholtz Zentrum München; Garching Germany
- German Center for Diabetes Research; DZD; Munich Germany
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28
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Botelho M, Cavadas C. Neuropeptide Y: An Anti-Aging Player? Trends Neurosci 2016; 38:701-711. [PMID: 26549884 DOI: 10.1016/j.tins.2015.08.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/27/2015] [Accepted: 08/28/2015] [Indexed: 12/16/2022]
Abstract
Accumulating evidence suggests that neuropeptide Y (NPY) has a role in aging and lifespan determination. In this review, we critically discuss age-related changes in NPY levels in the brain, together with recent findings concerning the contribution of NPY to, and impact on, six hallmarks of aging, specifically: loss of proteostasis, stem cell exhaustion, altered intercellular communication, deregulated nutrient sensing, cellular senescence, and mitochondrial dysfunction. Understanding how NPY contributes to, and counteracts, these hallmarks of aging will open new avenues of research on limiting damage related to aging.
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Affiliation(s)
- Mariana Botelho
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Cláudia Cavadas
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal.
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29
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Neuropeptide Y (NPY) as a therapeutic target for neurodegenerative diseases. Neurobiol Dis 2016; 95:210-24. [PMID: 27461050 DOI: 10.1016/j.nbd.2016.07.022] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/29/2016] [Accepted: 07/20/2016] [Indexed: 12/16/2022] Open
Abstract
Neuropeptide Y (NPY) and NPY receptors are widely expressed in the mammalian central nervous system. Studies in both humans and rodent models revealed that brain NPY levels are altered in some neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, Huntington's disease and Machado-Joseph disease. In this review, we will focus on the roles of NPY in the pathological mechanisms of these disorders, highlighting NPY as a neuroprotective agent, as a neural stem cell proliferative agent, as an agent that increases trophic support, as a stimulator of autophagy and as an inhibitor of excitotoxicity and neuroinflammation. Moreover, the effect of NPY in some clinical manifestations commonly observed in Alzheimer's disease, Parkinson's disease, Huntington's disease and Machado-Joseph disease, such as depressive symptoms and body weight loss, are also discussed. In conclusion, this review highlights NPY system as a potential therapeutic target in neurodegenerative diseases.
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30
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Steyn FJ, Tolle V, Chen C, Epelbaum J. Neuroendocrine Regulation of Growth Hormone Secretion. Compr Physiol 2016; 6:687-735. [PMID: 27065166 DOI: 10.1002/cphy.c150002] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This article reviews the main findings that emerged in the intervening years since the previous volume on hormonal control of growth in the section on the endocrine system of the Handbook of Physiology concerning the intra- and extrahypothalamic neuronal networks connecting growth hormone releasing hormone (GHRH) and somatostatin hypophysiotropic neurons and the integration between regulators of food intake/metabolism and GH release. Among these findings, the discovery of ghrelin still raises many unanswered questions. One important event was the application of deconvolution analysis to the pulsatile patterns of GH secretion in different mammalian species, including Man, according to gender, hormonal environment and ageing. Concerning this last phenomenon, a great body of evidence now supports the role of an attenuation of the GHRH/GH/Insulin-like growth factor-1 (IGF-1) axis in the control of mammalian aging.
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Affiliation(s)
- Frederik J Steyn
- University of Queensland Centre for Clinical Research and the School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Virginie Tolle
- Unité Mixte de Recherche en Santé 894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Jacques Epelbaum
- University of Queensland Centre for Clinical Research and the School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
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31
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Bauer PV, Hamr SC, Duca FA. Regulation of energy balance by a gut-brain axis and involvement of the gut microbiota. Cell Mol Life Sci 2016; 73:737-55. [PMID: 26542800 PMCID: PMC11108299 DOI: 10.1007/s00018-015-2083-z] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 10/22/2015] [Accepted: 10/26/2015] [Indexed: 12/11/2022]
Abstract
Despite significant progress in understanding the homeostatic regulation of energy balance, successful therapeutic options for curbing obesity remain elusive. One potential target for the treatment of obesity is via manipulation of the gut-brain axis, a complex bidirectional communication system that is crucial in maintaining energy homeostasis. Indeed, ingested nutrients induce secretion of gut peptides that act either via paracrine signaling through vagal and non-vagal neuronal relays, or in an endocrine fashion via entry into circulation, to ultimately signal to the central nervous system where appropriate responses are generated. We review here the current hypotheses of nutrient sensing mechanisms of enteroendocrine cells, including the release of gut peptides, mainly cholecystokinin, glucagon-like peptide-1, and peptide YY, and subsequent gut-to-brain signaling pathways promoting a reduction of food intake and an increase in energy expenditure. Furthermore, this review highlights recent research suggesting this energy regulating gut-brain axis can be influenced by gut microbiota, potentially contributing to the development of obesity.
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Affiliation(s)
- Paige V Bauer
- Department of Medicine, Toronto General Research Institute, UHN, Toronto, ON, M5G 1L7, Canada
- Department of Physiology, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Sophie C Hamr
- Department of Medicine, Toronto General Research Institute, UHN, Toronto, ON, M5G 1L7, Canada
- Department of Physiology, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Frank A Duca
- Department of Medicine, Toronto General Research Institute, UHN, Toronto, ON, M5G 1L7, Canada.
- MaRS Centre, Toronto Medical Discovery Tower, Room 10-701H, 101 College Street, Toronto, ON, M5G 1L7, Canada.
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32
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Qi Y, Fu M, Herzog H. Y2 receptor signalling in NPY neurons controls bone formation and fasting induced feeding but not spontaneous feeding. Neuropeptides 2016; 55:91-7. [PMID: 26444586 DOI: 10.1016/j.npep.2015.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 09/25/2015] [Accepted: 09/25/2015] [Indexed: 12/24/2022]
Abstract
Y2 receptors have been implicated in the development of obesity and are a potential target for obesity treatment due to their known role of inhibiting neuropeptide Y (NPY) induced feeding responses. However, the precise neuronal population on which Y2 receptors act to fulfil this role is less clear. Here we utilise a novel inducible, postnatal onset NPY neurons specific deletion model to investigate the functional consequences of loss of Y2 signalling in this population of neurons on feeding and energy homeostasis regulation. While the consequences of lack of Y2 signalling in NPY neurons are confirmed in terms of the uncoupling of suppression/increasing of NPY and pro-opiomelanocortin (POMC) mRNA expression in the arcuate nuclei (Arc), respectively, this lack of Y2 signalling surprisingly does not have any significant effect on spontaneous food intake. Fasting induced food intake, however, is strongly increased but only in the first 1h after re-feeding. Consequently no significant changes in body weight are being observed although body weight gain is increased in male mice after postnatal onset Y2 deletion. Importantly, another known function of central Y2 receptor signalling, the suppression of bone formation is conserved in this conditional model with whole body bone mineral content being decreased. Taken together this model confirms the critical role of Y2 signalling to control NPY and associated POMC expression in the Arc, but also highlights the possibility that others, non-NPY neuronal Y2 receptors, are also involved in controlling feeding and energy homeostasis regulation.
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Affiliation(s)
- Yue Qi
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia.
| | - Melissa Fu
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
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Qi Y, Purtell L, Fu M, Lee NJ, Aepler J, Zhang L, Loh K, Enriquez RF, Baldock PA, Zolotukhin S, Campbell LV, Herzog H. Snord116 is critical in the regulation of food intake and body weight. Sci Rep 2016; 6:18614. [PMID: 26726071 PMCID: PMC4698587 DOI: 10.1038/srep18614] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 11/23/2015] [Indexed: 12/27/2022] Open
Abstract
Prader-Willi syndrome (PWS) is the predominant genetic cause of obesity in humans. Recent clinical reports have suggested that micro-deletion of the Snord116 gene cluster can lead to PWS, however, the extent of the contributions of the encoded snoRNAs is unknown. Here we show that mice lacking Snord116 globally have low birth weight, increased body weight gain, energy expenditure and hyperphagia. Consistent with this, microarray analysis of hypothalamic gene expression revealed a significant alteration in feeding related pathways that was also confirmed by in situ hybridisation. Importantly, selective deletion of Snord116 only from NPY expressing neurons mimics almost exactly the global deletion phenotype including the persistent low birth weight, increased body weight gain in early adulthood, increased energy expenditure and hyperphagia. Mechanistically, the lack of Snord116 in NPY neurons leads to the upregulation of NPY mRNA consistent with the hyperphagic phenotype and suggests a critical role of Snord116 in the control of NPY neuronal functions that might be dysregulated in PWS.
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Affiliation(s)
- Yue Qi
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Louise Purtell
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Melissa Fu
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Nicola J Lee
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Julia Aepler
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Lei Zhang
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Kim Loh
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Ronaldo F Enriquez
- Bone Biology Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Paul A Baldock
- Bone Biology Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Sergei Zolotukhin
- Department of Pediatrics, College of Medicine, Center for Smell and Taste, University of Florida, Gainesville, Florida 32610, USA
| | - Lesley V Campbell
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia.,School of Medical Sciences, University of NSW, NSW, Australia
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Abstract
During the last decades, obesity and osteoporosis have become important global health problems, and the belief that obesity is protective against osteoporosis has recently come into question. In fact, some recent epidemiologic and clinical studies have shown that a high level of fat mass might be a risk factor for osteoporosis and fragility fractures. Several potential mechanisms have been proposed to explain the complex relationship between adipose tissue and bone. Indeed, adipose tissue secretes various molecules, named adipokines, which are thought to have effects on metabolic, skeletal and cardiovascular systems. Moreover, fat tissue is one of the major sources of aromatase, an enzyme that synthesizes estrogens from androgen precursors, hormones that play a pivotal role in the maintenance of skeletal homeostasis, protecting against osteoporosis. Moreover, bone cells express several specific hormone receptors and recent observations have shown that bone-derived factors, such as osteocalcin and osteopontin, affect body weight control and glucose homeostasis. Thus, the skeleton is considered an endocrine target organ and an endocrine organ itself, likely influencing other organs as well. Finally, adipocytes and osteoblasts originate from a common progenitor, a pluripotential mesenchymal stem cell, which has an equal propensity for differentiation into adipocytes or osteoblasts (or other lines) under the influence of several cell-derived transcription factors. This review will highlight recent insights into the relationship between fat and bone, evaluating both potential positive and negative influences between adipose and bone tissue. It will also focus on the hypothesis that osteoporosis might be considered the obesity of bone.
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Affiliation(s)
- Emanuela A. Greco
- Department of Experimental Medicine, Section of Medical Pathophysiology, Endocrinology and Nutrition, ‘Sapienza’ University of Rome, Rome, Italy
| | - Andrea Lenzi
- Department of Experimental Medicine, Section of Medical Pathophysiology, Endocrinology and Nutrition, ‘Sapienza’ University of Rome, Rome, Italy
| | - Silvia Migliaccio
- Unit of Endocrinology, Department of Movement, Human and Health Sciences, Section of Health Sciences, ‘Foro Italico’ University of Rome, Largo Lauro De Bosis 15, 00195 Rome, Italy
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35
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Wood J, Verma D, Lach G, Bonaventure P, Herzog H, Sperk G, Tasan RO. Structure and function of the amygdaloid NPY system: NPY Y2 receptors regulate excitatory and inhibitory synaptic transmission in the centromedial amygdala. Brain Struct Funct 2015; 221:3373-91. [PMID: 26365505 PMCID: PMC4696156 DOI: 10.1007/s00429-015-1107-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 09/04/2015] [Indexed: 12/14/2022]
Abstract
The amygdala is essential for generating emotional-affective behaviors. It consists of several nuclei with highly selective, elaborate functions. In particular, the central extended amygdala, consisting of the central amygdala (CEA) and the bed nucleus of the stria terminalis (BNST) is an essential component actively controlling efferent connections to downstream effectors like hypothalamus and brain stem. Both, CEA and BNST contain high amounts of different neuropeptides that significantly contribute to synaptic transmission. Among these, neuropeptide Y (NPY) has emerged as an important anxiolytic and fear-reducing neuromodulator. Here, we characterized the expression, connectivity and electrophysiological function of NPY and Y2 receptors within the CEA. We identified several NPY-expressing neuronal populations, including somatostatin- and calretinin-expressing neurons. Furthermore, in the main intercalated nucleus, NPY is expressed primarily in dopamine D1 receptor-expressing neurons but also in interspersed somatostatin-expressing neurons. Interestingly, NPY neurons did not co-localize with the Y2 receptor. Retrograde tract tracing experiments revealed that NPY neurons reciprocally connect the CEA and BNST. Functionally, the Y2 receptor agonist PYY3-36, reduced both, inhibitory as well as excitatory synaptic transmission in the centromedial amygdala (CEm). However, we also provide evidence that lack of NPY or Y2 receptors results in increased GABA release specifically at inhibitory synapses in the CEm. Taken together, our findings suggest that NPY expressed by distinct populations of neurons can modulate afferent and efferent projections of the CEA via presynaptic Y2 receptors located at inhibitory and excitatory synapses.
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Affiliation(s)
- J Wood
- Department of Pharmacology, Medical University Innsbruck, Peter-Mayr-Strasse 1a, 6020, Innsbruck, Austria
| | - D Verma
- Department of Pharmacology, Medical University Innsbruck, Peter-Mayr-Strasse 1a, 6020, Innsbruck, Austria.,Institute of Physiology I (Neurophysiology), Westfälische Wilhelms-Universität, Munster, Germany
| | - G Lach
- Department of Pharmacology, Medical University Innsbruck, Peter-Mayr-Strasse 1a, 6020, Innsbruck, Austria.,Capes Foundation, Ministry of Education of Brazil, Brasília, DF, 70040-020, Brazil
| | - P Bonaventure
- Janssen Research & Development, LLC, San Diego, CA, USA
| | - H Herzog
- Neuroscience Division, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW, 2010, Australia
| | - G Sperk
- Department of Pharmacology, Medical University Innsbruck, Peter-Mayr-Strasse 1a, 6020, Innsbruck, Austria
| | - R O Tasan
- Department of Pharmacology, Medical University Innsbruck, Peter-Mayr-Strasse 1a, 6020, Innsbruck, Austria.
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Verma D, Wood J, Lach G, Mietzsch M, Weger S, Heilbronn R, Herzog H, Bonaventure P, Sperk G, Tasan RO. NPY Y2 receptors in the central amygdala reduce cued but not contextual fear. Neuropharmacology 2015; 99:665-74. [PMID: 26314208 DOI: 10.1016/j.neuropharm.2015.08.038] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 08/18/2015] [Accepted: 08/21/2015] [Indexed: 10/23/2022]
Abstract
The amygdala is fundamental for associative fear and extinction learning. Recently, also the central nucleus of the amygdala (CEA) has emerged as a site of plasticity actively controlling efferent connections to downstream effector brain areas. Although synaptic transmission is primarily mediated by glutamate and GABA, neuropeptides critically influence the overall response. While neuropeptide Y (NPY) acting via postsynaptic Y1 receptors exerts an important anxiolytic and fear-reducing action, the role of the predominantly presynaptic Y2 receptors is less defined. To investigate the role of Y2 receptors in the CEA we employed viral-vector mediated over-expression of the Y2 selective agonist NPY3-36 in fear conditioning and extinction experiments. NPY3-36 over-expression in the CEA resulted in reduced fear expression during fear acquisition and recall. Interestingly, this effect was blocked by intraperitoneal injection of a brain-penetrant Y2 receptor antagonist. Furthermore, over-expression of NPY3-36 in the CEA also reduced fear expression during fear extinction of CS-induced but not context-related fear. Again, fear extinction appeared delayed by peripheral injection of a Y2 receptor antagonist JNJ-31020028. Importantly, mice with over-expression of NPY3-36 in the CEA also displayed reduced spontaneous recovery and reinstatement, suggesting that Y2 receptor activation supports a permanent suppression of fear. Local deletion of Y2 receptors in the CEA, on the other hand, increased the expression of CS-induced freezing during fear recall and fear extinction. Thus, NPY inhibits fear learning and promotes cued extinction by reducing fear expression also via activation of presynaptic Y2 receptors on CEA neurons.
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Affiliation(s)
- D Verma
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - J Wood
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - G Lach
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria; Capes Foundation, Ministry of Education of Brazil, 70040-020 Brasília, DF, Brazil
| | - M Mietzsch
- Institute of Virology, Campus Benjamin Franklin, Charité Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - S Weger
- Institute of Virology, Campus Benjamin Franklin, Charité Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - R Heilbronn
- Institute of Virology, Campus Benjamin Franklin, Charité Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - H Herzog
- Neuroscience Division, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
| | - P Bonaventure
- Janssen Research & Development, LLC, San Diego, CA, USA
| | - G Sperk
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - R O Tasan
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria.
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Genome-wide microRNA screening reveals that the evolutionary conserved miR-9a regulates body growth by targeting sNPFR1/NPYR. Nat Commun 2015; 6:7693. [PMID: 26138755 PMCID: PMC4506552 DOI: 10.1038/ncomms8693] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/02/2015] [Indexed: 12/02/2022] Open
Abstract
MicroRNAs (miRNAs) regulate many physiological processes including body growth. Insulin/IGF signalling is the primary regulator of animal body growth, but the extent to which miRNAs act in insulin-producing cells (IPCs) is unclear. Here we generate a UAS-miRNA library of Drosophila stocks and perform a genetic screen to identify miRNAs whose overexpression in the IPCs inhibits body growth in Drosophila. Through this screen, we identify miR-9a as an evolutionarily conserved regulator of insulin signalling and body growth. IPC-specific miR-9a overexpression reduces insulin signalling and body size. Of the predicted targets of miR-9a, we find that loss of miR-9a enhances the level of sNPFR1. We show via an in vitro binding assay that miR-9a binds to sNPFR1 mRNA in insect cells and to the mammalian orthologue NPY2R in rat insulinoma cells. These findings indicate that the conserved miR-9a regulates body growth by controlling sNPFR1/NPYR-mediated modulation of insulin signalling. Insulin signaling governs many physiological processes but the molecular and neural mechanisms of its regulation are largely unknown. Here the authors describe a novel molecular pathway controlling sNPF regulation of insulin signalling in the fruit fly, which is mediated by the evolutionary conserved miR-9a.
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Qi Y, Inoue K, Fu M, Inui A, Herzog H. Chronic overproduction of ghrelin in the hypothalamus leads to temporal increase in food intake and body weight. Neuropeptides 2015; 50:23-8. [PMID: 25801577 DOI: 10.1016/j.npep.2015.02.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/03/2015] [Accepted: 02/09/2015] [Indexed: 11/28/2022]
Abstract
Ghrelin is known to be a critical stimulator of feeding behavior mainly via actions in the hypothalamus. However, its functional contribution to the control of energy homeostasis under chronic elevated conditions is unknown. Here we show that overproduction of ghrelin via an AAV viral delivery system in the hypothalamus leads to an increase in food intake associated with increases in body weight. However, this increase in food intake is only temporary and is diminished and no longer significant after 3 weeks. Analysis of brain sections of mice 6 weeks after AAV-ghrelin virus injection demonstrates unaltered neuropeptide Y levels but strongly up-regulated pro-opiomelanocortin levels indicating that a compensatory mechanism has been activated to counter regulate the feeding stimulatory actions of ghrelin. This demonstrates that control mechanism exists that is activated under conditions of prolonged high ghrelin levels, which could potentially be utilized to control feeding and the development of obesity.
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Affiliation(s)
- Y Qi
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - K Inoue
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia; Department of Psychosomatic Internal Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - M Fu
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia
| | - A Inui
- Department of Psychosomatic Internal Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - H Herzog
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst, NSW, Australia; School of Medical Sciences, University of NSW, NSW, Australia.
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Fernando HA, Zibellini J, Hsu MS, Seimon RV, Nguyen AD, Sainsbury A. The neuropeptide Y-ergic system: potential therapeutic target against bone loss with obesity treatments. Expert Rev Endocrinol Metab 2015; 10:177-191. [PMID: 30293515 DOI: 10.1586/17446651.2015.1001741] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Obesity is no longer considered to provide protection against osteoporosis. Moreover, treatments for obesity are now suspected of reducing bone mass. With the escalating incidence of obesity, combined with increases in the frequency, duration and intensity of interventions used to combat it, we face a potential increase in health burden due to osteoporotic fractures. The neuropeptide Y-ergic system offers a potential target for the prevention and anabolic treatment of bone loss in obesity, due to its dual role in the regulation of energy homeostasis and bone mass. Although the strongest stimulation of bone mass by this system appears to occur via indirect hypothalamic pathways involving Y2 receptors (one of the five types of receptors for neuropeptide Y), Y1 receptors on osteoblasts (bone-forming cells) induce direct effects to enhance bone mass. This latter pathway may offer a suitable target for anti-osteoporotic treatment while also minimizing the risk of adverse side effects.
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Affiliation(s)
- Hamish A Fernando
- a 1 The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Sydney Medical School, The University of Sydney, Camperdown NSW 2006, Australia
| | - Jessica Zibellini
- a 1 The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Sydney Medical School, The University of Sydney, Camperdown NSW 2006, Australia
| | - Michelle Sh Hsu
- a 1 The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Sydney Medical School, The University of Sydney, Camperdown NSW 2006, Australia
| | - Radhika V Seimon
- a 1 The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Sydney Medical School, The University of Sydney, Camperdown NSW 2006, Australia
| | - Amy D Nguyen
- b 2 Neuroscience Program, Garvan Institute of Medical Research, University of New South Wales, Darlinghurst, Australia
| | - Amanda Sainsbury
- a 1 The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Sydney Medical School, The University of Sydney, Camperdown NSW 2006, Australia
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Actions of NPY, and its Y1 and Y2 receptors on pulsatile growth hormone secretion during the fed and fasted state. J Neurosci 2015; 34:16309-19. [PMID: 25471570 DOI: 10.1523/jneurosci.4622-13.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The hypothalamic NPY system plays an important role in regulating food intake and energy expenditure. Different biological actions of NPY are assigned to NPY receptor subtypes. Recent studies demonstrated a close relationship between food intake and growth hormone (GH) secretion; however, the mechanism through which endogenous NPY modulates GH release remains unknown. Moreover, conclusive evidence demonstrating a role for NPY and Y-receptors in regulating the endogenous pulsatile release of GH does not exist. We used genetically modified mice (germline Npy, Y1, and Y2 receptor knock-out mice) to assess pulsatile GH secretion under both fed and fasting conditions. Deletion of NPY did not impact fed GH release; however, it reversed the fasting-induced suppression of pulsatile GH secretion. The recovery of GH secretion was associated with a reduction in hypothalamic somatotropin release inhibiting factor (Srif; somatostatin) mRNA expression. Moreover, observations revealed a differential role for Y1 and Y2 receptors, wherein the postsynaptic Y1 receptor suppresses GH secretion in fasting. In contrast, the presynaptic Y2 receptor maintains normal GH output under long-term ad libitum-fed conditions. These data demonstrate an integrated neural circuit that modulates GH release relative to food intake, and provide essential information to address the differential roles of Y1 and Y2 receptors in regulating the release of GH under fed and fasting states.
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Zhang W, Cline MA, Gilbert ER. Hypothalamus-adipose tissue crosstalk: neuropeptide Y and the regulation of energy metabolism. Nutr Metab (Lond) 2014; 11:27. [PMID: 24959194 PMCID: PMC4066284 DOI: 10.1186/1743-7075-11-27] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 06/02/2014] [Indexed: 01/24/2023] Open
Abstract
Neuropeptide Y (NPY) is an orexigenic neuropeptide that plays a role in regulating adiposity by promoting energy storage in white adipose tissue and inhibiting brown adipose tissue activation in mammals. This review describes mechanisms underlying NPY's effects on adipose tissue energy metabolism, with an emphasis on cellular proliferation, adipogenesis, lipid deposition, and lipolysis in white adipose tissue, and brown fat activation and thermogenesis. In general, NPY promotes adipocyte differentiation and lipid accumulation, leading to energy storage in adipose tissue, with effects mediated mainly through NPY receptor sub-types 1 and 2. This review highlights hypothalamus-sympathetic nervous system-adipose tissue innervation and adipose tissue-hypothalamus feedback loops as pathways underlying these effects. Potential sources of NPY that mediate adipose effects include the bloodstream, sympathetic nerve terminals that innervate the adipose tissue, as well as adipose tissue-derived cells. Understanding the role of central vs. peripherally-derived NPY in whole-body energy balance could shed light on mechanisms underlying the pathogenesis of obesity. This information may provide some insight into searching for alternative therapeutic strategies for the treatment of obesity and associated diseases.
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Affiliation(s)
- Wei Zhang
- 3200 Litton-Reaves, Animal & Poultry Sciences Department, Virginia Tech, Blacksburg, VA 24061-0306, USA
| | - Mark A Cline
- 3200 Litton-Reaves, Animal & Poultry Sciences Department, Virginia Tech, Blacksburg, VA 24061-0306, USA
| | - Elizabeth R Gilbert
- 3200 Litton-Reaves, Animal & Poultry Sciences Department, Virginia Tech, Blacksburg, VA 24061-0306, USA
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Zhang L, Lee ICJ, Enriquez RF, Lau J, Vähätalo LH, Baldock PA, Savontaus E, Herzog H. Stress- and diet-induced fat gain is controlled by NPY in catecholaminergic neurons. Mol Metab 2014; 3:581-91. [PMID: 25061562 PMCID: PMC4099511 DOI: 10.1016/j.molmet.2014.05.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 05/06/2014] [Indexed: 12/02/2022] Open
Abstract
Neuropeptide Y (NPY) and noradrenaline are commonly co-expressed in sympathetic neurons. Both are key regulators of energy homeostasis and critical for stress-coping. However, little is known about the specific function of NPY in the catecholaminergic system in these regulations. Here we show that mice with NPY expression only in the noradrenergic and adrenergic cells of the catecholaminergic system (catNPY) exhibited exacerbated diet-induced obesity, lower body and brown adipose tissue temperatures compared to WT and NPY−/− mice under a HFD. Furthermore, chronic stress increased adiposity and serum corticosterone level in WT but not NPY−/− mice. Re-introducing NPY specifically to the catecholaminergic system in catNPY mice restored stress responsiveness associated with increased respiratory exchange ratio and decreased liver pACC to tACC ratio. These results demonstrate catecholaminergic NPY signalling is critical in mediating diet- and chronic stress-induced fat gain via effects on diet-induced thermogenesis and stress-induced increases in corticosterone levels and lipogenic capacity.
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Affiliation(s)
- Lei Zhang
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney 2010, Australia ; St Vincent's Clinical School, UNSW Australia, Sydney 2052, Australia
| | - I-Chieh J Lee
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney 2010, Australia
| | - Rondaldo F Enriquez
- Osteoporosis and Bone Biology Division, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney 2010, Australia
| | - Jackie Lau
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney 2010, Australia
| | - Laura H Vähätalo
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney 2010, Australia
| | - Paul A Baldock
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney 2010, Australia
| | - Eriika Savontaus
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney 2010, Australia ; Faculty of Medicine, UNSW Australia, Sydney 2052, Australia
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43
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Abstract
Many molecules are involved in the regulation of feeding behavior, and they and their receptors are located in the brain hypothalamus and adipocytes. On the basis of evidence suggesting an association between the brain and adipose tissue, we propose the concept of the brain-adipose axis. This model consists of (l) the expression of endogenous molecules and/or their receptors in the hypothalamus and peripheral adipose tissue, (2) the function of these molecules as appetite regulators in the brain, (3) their existence in the general circulation as secreted proteins and (4) the physiological affects of these molecules on fat cell size and number. These molecules can be divided into two anorexigenic and orexigenic classes. In adipose tissue, all orexigenic molecules possess adipogenic activity, and almost all anorexigenic molecules suppress fat cell proliferation. Although the manner, in which they present in the circulating blood connect the brain and peripheral adipocytes, remains to be well-organized, these observations suggest the positive feedback axis affecting molecules in the hypothalamus and adipose tissue. Analysis of the disturbance and dysregulation of this axis might promote the development of new anti-obesity drugs useful in treating the metabolic syndrome.
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Affiliation(s)
- Hiroyuki Shimizu
- Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
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44
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Scheid J, Birch L, Williams N, Rolls B, De Souza M. Postprandial peptide YY is lower in young college-aged women with high dietary cognitive restraint. Physiol Behav 2013; 120:26-33. [DOI: 10.1016/j.physbeh.2013.06.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 03/05/2013] [Accepted: 06/27/2013] [Indexed: 01/09/2023]
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Heredity and cardiometabolic risk: naturally occurring polymorphisms in the human neuropeptide Y(2) receptor promoter disrupt multiple transcriptional response motifs. J Hypertens 2013; 31:123-33. [PMID: 23149563 DOI: 10.1097/hjh.0b013e32835b053d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVES The neuropeptide Y(2) G-protein-coupled receptor (NPY2R) relays signals from PYY or neuropeptide Y toward satiety and control of body mass. Targeted ablation of the NPY2R locus in mice yields obesity, and studies of NPY2R promoter genetic variation in more than 10,000 human participants indicate its involvement in control of obesity and BMI. Here we searched for genetic variation across the human NPY2R locus and probed its functional effects, especially in the proximal promoter. METHODS AND RESULTS Twin pair studies indicated substantial heritability for multiple cardiometabolic traits, including BMI, SBP, DBP, and PYY, an endogenous agonist at NPY2R. Systematic polymorphism discovery by resequencing across NPY2R uncovered 21 genetic variants, 10 of which were common [minor allele frequency (MAF) >5%], creating one to two linkage disequilibrium blocks in multiple biogeographic ancestries. In vivo, NPY2R haplotypes were associated with both BMI (P = 3.75E-04) and PYY (P = 4.01E-06). Computational approaches revealed that proximal promoter variants G-1606A, C-599T, and A-224G disrupt predicted IRF1 (A>G), FOXI1 (T>C), and SNAI1 (A>G) response elements. In neuroendocrine cells transfected with NPY2R promoter/luciferase reporter plasmids, all three variants and their resulting haplotypes influenced transcription (G-1606A, P < 2.97E-06; C-599T, P < 1.17E-06; A-224G, P < 2.04E-06), and transcription was differentially augmented or impaired by coexpression of either the cognate full-length transcription factors or their specific siRNAs at each site. Endogenous expression of transcripts for NPY2R, IRF1, and SNAI1 was documented in neuroendocrine cells, and the NPY2R mRNA was differentially expressed in two neuroendocrine tissues (adrenal gland, brainstem) of a rodent model of hypertension and the metabolic syndrome, the spontaneously hypertensive rat. CONCLUSION We conclude that common genetic variation in the proximal NPY2R promoter influences transcription factor binding so as to alter gene expression in neuroendocrine cells, and consequently cardiometabolic traits in humans. These results unveil a novel control point, whereby cis-acting genetic variation contributes to control of complex cardiometabolic traits, and point to new transcriptional strategies for intervention into neuropeptide actions and their cardiometabolic consequences.
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46
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Reidelberger R, Haver A, Chelikani PK. Role of peptide YY(3-36) in the satiety produced by gastric delivery of macronutrients in rats. Am J Physiol Endocrinol Metab 2013; 304:E944-50. [PMID: 23482449 PMCID: PMC3651646 DOI: 10.1152/ajpendo.00075.2013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Peptide YY(3-36) [PYY(3-36)] is postulated to act as a hormonal signal from gut to brain to inhibit food intake. PYY(3-36) potently reduces food intake when administered systemically or into the brain. If action of endogenous PYY(3-36) is necessary for normal satiation to occur, then pharmacological blockade of its receptors should increase food intake. Here, we determined the effects of iv infusion of Y1, Y2, and Y5 receptor antagonists (BIBP 3226, BIIE 0246, CGP 71683) during the first 3 h of the dark period on food intake in non-food-deprived rats. Our results showed that 1) Y2 receptor blockade reversed the anorexic response to iv infusion of PYY(3-36) but did not increase food intake when administered alone; 2) Y1 and Y5 receptor antagonists neither attenuated PYY(3-36)-induced anorexia nor altered food intake when given alone; and 3) Y2 receptor blockade attenuated anorexic responses to gastric infusions of casein hydrolysate and long-chain triglycerides, but not maltodextrin. Previous work showed that Y2 antagonist BIIE 0246 does not penetrate the blood-brain barrier. Together, these results support the hypothesis that gut PYY(3-36) action at Y2 receptors peripheral to the blood brain barrier plays an essential role in mediating satiety responses to gastric delivery of protein and long-chain triglycerides, but not polysaccharide.
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Affiliation(s)
- Roger Reidelberger
- Veterans Affairs Research Service, Veterans Affairs Nebraska Western Iowa Health Care System, Omaha, NE 68105, USA
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47
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Zhou JR, Zhang LD, Wei HF, Wang X, Ni HL, Yang F, Zhang T, Jiang CL. Neuropeptide Y induces secretion of high-mobility group box 1 protein in mouse macrophage via PKC/ERK dependent pathway. J Neuroimmunol 2013; 260:55-9. [PMID: 23623189 DOI: 10.1016/j.jneuroim.2013.04.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 03/25/2013] [Accepted: 04/03/2013] [Indexed: 11/26/2022]
Abstract
Despite increasing evidence highlighting the role of NPY in the modulation of inflammatory reaction, surprisingly little is known about the direct effects of NPY on the release of proinflammatory mediators. In the present work, we have evaluated the effects of NPY on the release of TNF-α, IL-1β, IL-6 and HMGB1 mediators in peritoneal macrophages. Our results demonstrate for the first time that NPY can directly induce active HMGB1 release and cytoplasmic translocation, while the production of TNF-α, IL-1β and IL-6 is not affected. PKC and ERK pathway inhibitors can abolish the promotive effect of NPY on HMGB1 secretion. Thus, our results indicate that NPY might impact on the innate immune system by directly potentiating the HMGB1 release from the macrophage.
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Affiliation(s)
- Jiang-Rui Zhou
- Laboratory of Stress Medicine, Second Military Medical University, No.800 Xiangyin Road, Shanghai 200433, PR China
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Wang Q, Whim MD. Stress-induced changes in adrenal neuropeptide Y expression are regulated by a negative feedback loop. J Neurochem 2013; 125:16-25. [PMID: 23311866 DOI: 10.1111/jnc.12150] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 12/20/2012] [Accepted: 01/02/2013] [Indexed: 12/21/2022]
Abstract
Neuropeptide Y is a co-transmitter that is synthesized by chromaffin cells in the adrenal medulla. During the fight-or-flight response these cells release NPY in addition to epinephrine and norepinephrine. Following the stress-induced reflex, the levels of NPY are increased as part of a homeostatic response that modulates catecholaminergic signaling. Here, we examined the control of NPY expression in mice after brief exposure to the cold water forced swim test. This treatment led to a shift in NPY expression between two populations of chromaffin cells that reversed over the course of 1 week. When NPY(GFP) BAC transgenic animals were exposed to stress, there was an increase in cytoplasmic, non-secretable GFP, indicating that stress increased NPY promoter activity. In vivo blockage of Y2 (but not Y1 or Y5) receptors increased basal adrenal NPY expression and so modulated the effects of stress. We conclude that release of NPY mediates a negative feedback loop that inhibits its own expression. Thus, the levels of NPY are determined by a balance between the potentiating effects of stress and the tonic inhibitory actions of Y2 receptors. This may be an efficient way to ensure the levels of this modulator do not decline following intense sympathetic activity.
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Affiliation(s)
- Qian Wang
- Department of Biology, Pennsylvania State University, State College, PA, USA
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49
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Shi YC, Lau J, Lin Z, Zhang H, Zhai L, Sperk G, Heilbronn R, Mietzsch M, Weger S, Huang XF, Enriquez RF, Baldock PA, Zhang L, Sainsbury A, Herzog H, Lin S. Arcuate NPY controls sympathetic output and BAT function via a relay of tyrosine hydroxylase neurons in the PVN. Cell Metab 2013; 17:236-48. [PMID: 23395170 DOI: 10.1016/j.cmet.2013.01.006] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 12/03/2012] [Accepted: 01/11/2013] [Indexed: 10/27/2022]
Abstract
Neuropepetide Y (NPY) is best known for its powerful stimulation of food intake and its effects on reducing energy expenditure. However, the pathways involved and the regulatory mechanisms behind this are not well understood. Here we demonstrate that NPY derived from the arcuate nucleus (Arc) is critical for the control of sympathetic outflow and brown adipose tissue (BAT) function. Mechanistically, a key change induced by Arc NPY signaling is a marked Y1 receptor-mediated reduction in tyrosine hydroxylase (TH) expression in the hypothalamic paraventricular nucleus (PVN), which is also associated with a reduction in TH expression in the locus coeruleus (LC) and other regions in the brainstem. Consistent with this, Arc NPY signaling decreased sympathetically innervated BAT thermogenesis, involving the downregulation of uncoupling protein 1 (UCP1) expression in BAT. Taken together, these data reveal a powerful Arc-NPY-regulated neuronal circuit that controls BAT thermogenesis and sympathetic output via TH neurons.
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Affiliation(s)
- Yan-Chuan Shi
- Neuroscience Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
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50
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Liu T, Wang Q, Berglund ED, Tong Q. Action of Neurotransmitter: A Key to Unlock the AgRP Neuron Feeding Circuit. Front Neurosci 2013; 6:200. [PMID: 23346045 PMCID: PMC3549528 DOI: 10.3389/fnins.2012.00200] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 12/31/2012] [Indexed: 01/08/2023] Open
Abstract
The current obesity epidemic and lack of efficient therapeutics demand a clear understanding of the mechanism underlying body weight regulation. Despite intensive research focus on obesity pathogenesis, an effective therapeutic strategy to treat and cure obesity is still lacking. Exciting studies in last decades have established the importance of hypothalamic agouti-related protein-expressing neurons (AgRP neurons) in the regulation of body weight homeostasis. AgRP neurons are both required and sufficient for feeding regulation. The activity of AgRP neurons is intricately regulated by nutritional hormones as well as synaptic inputs from upstream neurons. Changes in AgRP neuron activity lead to alterations in the release of mediators, including neuropeptides Neuropeptide Y (NPY) and AgRP, and fast-acting neurotransmitter GABA. Recent studies based on mouse genetics, novel optogenetics, and designer receptor exclusively activated by designer drugs have identified a critical role for GABA release from AgRP neurons in the parabrachial nucleus and paraventricular hypothalamus in feeding control. This review will summarize recent findings about AgRP neuron-mediated control of feeding circuits with a focus on the role of neurotransmitters. Given the limited knowledge on feeding regulation, understanding the action of neurotransmitters may be a key to unlock neurocircuitry that governs feeding.
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Affiliation(s)
- Tiemin Liu
- Division of Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas Dallas, TX, USA
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