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Dettori C, Ronca F, Scalese M, Saponaro F. Parathyroid Hormone (PTH)-Related Peptides Family: An Intriguing Role in the Central Nervous System. J Pers Med 2023; 13:jpm13050714. [PMID: 37240884 DOI: 10.3390/jpm13050714] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 04/17/2023] [Accepted: 04/21/2023] [Indexed: 05/28/2023] Open
Abstract
Parathyroid Hormone (PTH) plays a crucial role in the maintenance of calcium homeostasis directly acting on bone and kidneys and indirectly on the intestine. However, a large family of PTH-related peptides exists that exerts other physiological effects on different tissues and organs, such as the Central Nervous System (CNS). In humans, PTH-related peptides are Parathyroid Hormone (PTH), PTH-like hormones (PTHrP and PTHLH), and tuberoinfundibular peptide of 39 (TIP39 or PTH2). With different affinities, these ligands can bind parathyroid receptor type 1 (PTH1R) and type 2 (PTH2R), which are part of the type II G-protein-coupled-receptors (GPCRs) family. The PTH/PTHrP/PTH1R system has been found to be expressed in many areas of the brain (hippocampus, amygdala, hypothalamus, caudate nucleus, corpus callosum, subthalamic nucleus, thalamus, substantia nigra, cerebellum), and literature data suggest the system exercises a protective action against neuroinflammation and neurodegeneration, with positive effects on memory and hyperalgesia. TIP39 is a small peptide belonging to the PTH-related family with a high affinity for PTH2R in the CNS. The TIP39/PTH2R system has been proposed to mediate many regulatory and functional roles in the brain and to modulate auditory, nociceptive, and sexual maturation functions. This review aims to summarize the knowledge of PTH-related peptides distribution and functions in the CNS and to highlight the gaps that still need to be filled.
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Affiliation(s)
- Cristina Dettori
- Biochemistry Laboratory, Department of Pathology, University of Pisa, 56126 Pisa, Italy
| | - Francesca Ronca
- Biochemistry Laboratory, Department of Pathology, University of Pisa, 56126 Pisa, Italy
| | - Marco Scalese
- Institute of Clinical Physiology, National Council of Research, 56126 Pisa, Italy
| | - Federica Saponaro
- Biochemistry Laboratory, Department of Pathology, University of Pisa, 56126 Pisa, Italy
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2
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Romagnoli C, Zonefrati R, Lucattelli E, Innocenti M, Civinini R, Iantomasi T, Brandi ML. In Vitro Effects of PTH (1-84) on Human Skeletal Muscle-Derived Satellite Cells. Biomedicines 2023; 11:biomedicines11041017. [PMID: 37189637 DOI: 10.3390/biomedicines11041017] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/15/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023] Open
Abstract
Parathyroid hormone (PTH) is a hormone secreted by the parathyroid glands. Despite its well-known characterized anabolic and catabolic actions on the skeleton, the in vitro effects of PTH on skeletal muscle cells are limited and generally performed on animal models. The aim of this study was to evaluate the effects of a short impulse of PTH (1-84) on the proliferation and the differentiation of skeletal muscle satellite cells isolated from human biopsies. The cells were exposed for 30 min to different concentrations of PTH (1-84), from 10−6 mol/L to 10−12 mol/L. ELISA was used to assay cAMP and the myosin heavy-chain (MHC) protein. The proliferation was assayed by BrdU and the differentiation by RealTime-qPCR. A statistical analysis was performed by ANOVA followed by Bonferroni’s test. No significant variations in cAMP and the proliferation were detected in the isolated cells treated with PTH. On the other hand, 10−7 mol/L PTH on differentiated myotubes has shown significant increases in cAMP (p ≤ 0.05), in the expression of myogenic differentiation genes (p ≤ 0.001), and in the MHC protein (p ≤ 0.01) vs. untreated controls. This work demonstrates for the first time the in vitro effects of PTH (1-84) on human skeletal muscle cells and it opens new fields of investigation in muscle pathophysiology.
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Keller D, Tsuda MC, Usdin TB, Dobolyi A. Behavioural actions of tuberoinfundibular peptide 39 (parathyroid hormone 2). J Neuroendocrinol 2022; 34:e13130. [PMID: 35499975 PMCID: PMC9515240 DOI: 10.1111/jne.13130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/20/2022] [Accepted: 03/23/2022] [Indexed: 12/31/2022]
Abstract
Tuberoinfundibular peptide of 39 residues (TIP39) acts via its endogenous class B G-protein coupled receptorthe parathyroid hormone 2 receptor (PTH2R). Hence, it is also known as parathyroid hormone 2. The peptide is expressed in the brain by a small number of neurons with a highly restricted distribution, which in turn project to a large number of brain regions that contain PTH2R. This peptide neuromodulator system has been extensively investigated over the past 20 years including its behavioural actions, such as its role in the control of nociception, fear and fear incubation, anxiety and depression-like behaviours, and maternal and social behaviours. It also influences thermoregulation and potentially auditory responses. TIP39 probably exerts direct effect on the neuronal networks controlling these behaviours based on the localization of PTH2R and local TIP39 actions. In addition, TIP39 also affects the secretion of several hypothalamic hormones providing the basis for indirect behavioural actions. Recently developed experimental tools have stimulated further behavioural investigations, and novel results obtained are discussed in this review.
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Affiliation(s)
- Dávid Keller
- ELKH‐ELTE Laboratory of Molecular and Systems Neurobiology, Eötvös Loránd Research Network and Eötvös Loránd UniversityBudapestHungary
- Laboratory of Neuromorphology, Department of Anatomy, Histology and EmbryologySemmelweis UniversityBudapestHungary
| | - Mumeko C. Tsuda
- Preclinical Behavior and Modeling Core, Uniformed Services UniversityBethesdaMarylandUSA
| | - Ted B. Usdin
- Systems Neuroscience Imaging Resource, National Institute of Mental Health, NIHBethesdaMarylandUSA
| | - Arpád Dobolyi
- ELKH‐ELTE Laboratory of Molecular and Systems Neurobiology, Eötvös Loránd Research Network and Eötvös Loránd UniversityBudapestHungary
- Department of Physiology and NeurobiologyEötvös Loránd UniversityBudapestHungary
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4
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Zhao F, Zhang C, Zhou Q, Hang K, Zou X, Chen Y, Wu F, Rao Q, Dai A, Yin W, Shen DD, Zhang Y, Xia T, Stevens RC, Xu HE, Yang D, Zhao L, Wang MW. Structural insights into hormone recognition by the human glucose-dependent insulinotropic polypeptide receptor. eLife 2021; 10:e68719. [PMID: 34254582 PMCID: PMC8298097 DOI: 10.7554/elife.68719] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/06/2021] [Indexed: 12/16/2022] Open
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) is a peptide hormone that exerts crucial metabolic functions by binding and activating its cognate receptor, GIPR. As an important therapeutic target, GIPR has been subjected to intensive structural studies without success. Here, we report the cryo-EM structure of the human GIPR in complex with GIP and a Gs heterotrimer at a global resolution of 2.9 Å. GIP adopts a single straight helix with its N terminus dipped into the receptor transmembrane domain (TMD), while the C terminus is closely associated with the extracellular domain and extracellular loop 1. GIPR employs conserved residues in the lower half of the TMD pocket to recognize the common segments shared by GIP homologous peptides, while uses non-conserved residues in the upper half of the TMD pocket to interact with residues specific for GIP. These results provide a structural framework of hormone recognition and GIPR activation.
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Affiliation(s)
- Fenghui Zhao
- School of Pharmacy, Fudan UniversityShanghaiChina
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
| | - Chao Zhang
- School of Life Science and Technology, ShanghaiTech UniversityShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Qingtong Zhou
- Department of Pharmacology, School of Basic Medical Sciences, Fudan UniversityShanghaiChina
| | - Kaini Hang
- School of Life Science and Technology, ShanghaiTech UniversityShanghaiChina
| | - Xinyu Zou
- School of Artificial Intelligence and Automation, Huazhong University of Science and TechnologyWuhanChina
| | - Yan Chen
- School of Pharmacy, Fudan UniversityShanghaiChina
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
- Department of Pharmacology, School of Basic Medical Sciences, Fudan UniversityShanghaiChina
| | - Fan Wu
- School of Life Science and Technology, ShanghaiTech UniversityShanghaiChina
| | - Qidi Rao
- School of Life Science and Technology, ShanghaiTech UniversityShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Antao Dai
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
| | - Wanchao Yin
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
| | - Dan-Dan Shen
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of MedicineHangzhouChina
| | - Yan Zhang
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of MedicineHangzhouChina
| | - Tian Xia
- School of Artificial Intelligence and Automation, Huazhong University of Science and TechnologyWuhanChina
| | - Raymond C Stevens
- School of Life Science and Technology, ShanghaiTech UniversityShanghaiChina
| | - H Eric Xu
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Dehua Yang
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
| | - Lihua Zhao
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Ming-Wei Wang
- School of Pharmacy, Fudan UniversityShanghaiChina
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
- School of Life Science and Technology, ShanghaiTech UniversityShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
- Department of Pharmacology, School of Basic Medical Sciences, Fudan UniversityShanghaiChina
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
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5
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Sardella A, Bellone F, Morabito N, Minisola S, Basile G, Corica F, Catalano A. The association between hypoparathyroidism and cognitive impairment: a systematic review. J Endocrinol Invest 2021; 44:905-919. [PMID: 32926396 DOI: 10.1007/s40618-020-01423-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 09/08/2020] [Indexed: 12/01/2022]
Abstract
CONTEXT AND PURPOSE Hypocalcemia and low parathyroid hormone levels have been commonly suggested as factors able to induce central nervous system disturbances. However, evidences on the occurrence of cognitive impairment are limited or underestimated. The aim of this review is, therefore, to systematically summarize the available evidence concerning the occurrence of cognitive impairment among subjects suffering from idiopathic or secondary hypoparathyroidism. METHODS A systematic selection of the available literature was performed by searching the online databases PubMed, Scopus and Web of Knowledge. RESULTS The present systematic review included sixteen case report articles and one cross-sectional controlled study. Case reports were the most representative literature sources and involved ten women and seven men. The presence of cognitive impairment was mostly discussed in association with idiopathic hypoparathyroidism (HPT); five articles described the occurrence of cognitive impairment following postsurgical HPT. The case-controlled study reported a significant presence of peculiar cognitive deficits (e.g. reduced inhibitory control, impairment in visuo-spatial functioning among, and psychomotor retardation) among HPT subjects compared to healthy controls, with serum total calcium and its product with phosphorus as independent predictors of neuropsychological dysfunctions. CONCLUSION Even though mostly based on single case reports, the presence of neuropsychological dysfunctions in the context of HPT appears to be a consistent core finding.
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Affiliation(s)
- A Sardella
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - F Bellone
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - N Morabito
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - S Minisola
- Department of Internal Medicine and Medical Disciplines, "Sapienza" Rome University, Rome, Italy
| | - G Basile
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - F Corica
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - A Catalano
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.
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6
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Tanaka T, Takao-Kawabata R, Takakura A, Shimazu Y, Nakatsugawa M, Ito A, Lee JW, Kawasaki K, Iimura T. Teriparatide relieves ovariectomy-induced hyperalgesia in rats, suggesting the involvement of functional regulation in primary sensory neurons by PTH-mediated signaling. Sci Rep 2020; 10:5346. [PMID: 32210273 PMCID: PMC7093455 DOI: 10.1038/s41598-020-62045-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 03/03/2020] [Indexed: 11/09/2022] Open
Abstract
Clinical studies have reported that teriparatide (TPTD), a human parathyroid hormone analog, reduces back pain in osteoporotic patients. However, the mechanistic insights of this pharmacological action remain elusive. This study investigated the antinociceptive effect of TPTD mainly on primary sensory neurons in ovariectomized (OVX) rats. The plantar test showed thermal hyperalgesia in the OVX rats, which was significantly, but not fully, recovered immediately after the initial TPTD administration. The von Frey test also demonstrated reduced withdrawal threshold in the OVX rats. This was partially recovered by TPTD. Consistently, the number and size of spinal microglial cells were significantly increased in the OVX rats, while TPTD treatment significantly reduced the number but not size of these cells. RNA sequencing-based bioinformatics of the dorsal root ganglia (DRG) demonstrated that changes in neuro-protective and inflammatory genes were involved in the pharmacological effect of TPTD. Most neurons in the DRG expressed substantial levels of parathyroid hormone 1 receptor. TPTD treatment of the cultured DRG-derived neuronal cells reduced the cAMP level and augmented the intracellular calcium level as the concentration increased. These findings suggest that TPTD targets neuronal cells as well as bone cells to exert its pharmacological action.
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Affiliation(s)
- Tomoya Tanaka
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni city, Shizuoka, 410-2321, Japan.,Department of Pharmacology, Graduate School of Dental Medicine, Hokkaido University, N13 W7, Sapporo, 060-8586, Japan
| | - Ryoko Takao-Kawabata
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni city, Shizuoka, 410-2321, Japan.
| | - Aya Takakura
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni city, Shizuoka, 410-2321, Japan.,Department of Pharmacology, Graduate School of Dental Medicine, Hokkaido University, N13 W7, Sapporo, 060-8586, Japan
| | - Yukari Shimazu
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni city, Shizuoka, 410-2321, Japan
| | - Momoko Nakatsugawa
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni city, Shizuoka, 410-2321, Japan
| | - Akitoshi Ito
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni city, Shizuoka, 410-2321, Japan
| | - Ji-Won Lee
- Department of Pharmacology, Graduate School of Dental Medicine, Hokkaido University, N13 W7, Sapporo, 060-8586, Japan.,Division of Bio-Imaging, Proteo-Science Center (PROS), Ehime University, Shitsukawa, Toon city, Ehime, 791-0295, Japan
| | - Koh Kawasaki
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni city, Shizuoka, 410-2321, Japan
| | - Tadahiro Iimura
- Department of Pharmacology, Graduate School of Dental Medicine, Hokkaido University, N13 W7, Sapporo, 060-8586, Japan. .,Division of Bio-Imaging, Proteo-Science Center (PROS), Ehime University, Shitsukawa, Toon city, Ehime, 791-0295, Japan.
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7
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Tamura T, Noda H, Joyashiki E, Hoshino M, Watanabe T, Kinosaki M, Nishimura Y, Esaki T, Ogawa K, Miyake T, Arai S, Shimizu M, Kitamura H, Sato H, Kawabe Y. Identification of an orally active small-molecule PTHR1 agonist for the treatment of hypoparathyroidism. Nat Commun 2016; 7:13384. [PMID: 27857062 PMCID: PMC5120204 DOI: 10.1038/ncomms13384] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 09/28/2016] [Indexed: 01/09/2023] Open
Abstract
Parathyroid hormone (PTH) is essential for calcium homeostasis and its action is mediated by the PTH type 1 receptor (PTHR1), a class B G-protein-coupled receptor. Hypoparathyroidism and osteoporosis can be treated with PTH injections; however, no orally effective PTH analogue is available. Here we show that PCO371 is a novel, orally active small molecule that acts as a full agonist of PTHR1. PCO371 does not affect the PTH type 2 receptor (PTHR2), and analysis using PTHR1–PTHR2 chimeric receptors indicated that Proline 415 of PTHR1 is critical for PCO371-mediated PTHR1 activation. Oral administration of PCO371 to osteopenic rats provokes a significant increase in bone turnover with limited increase in bone mass. In hypocalcemic rats, PCO371 restores serum calcium levels without increasing urinary calcium, and with stronger and longer-lasting effects than PTH injections. These results strongly suggest that PCO371 can provide a new treatment option for PTH-related disorders, including hypoparathyroidism. Hypoparathyroidism and osteoporosis can be treated with parathyroid hormone, but frequent injections are required. Here the authors develop a small-molecule agonist for the parathyroid hormone type I receptor that can be administered orally, and demonstrate its efficacy in rats.
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Affiliation(s)
- Tatsuya Tamura
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Hiroshi Noda
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Eri Joyashiki
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Maiko Hoshino
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Tomoyuki Watanabe
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Masahiko Kinosaki
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Yoshikazu Nishimura
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Tohru Esaki
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Kotaro Ogawa
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Taiji Miyake
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Shinichi Arai
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Masaru Shimizu
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Hidetomo Kitamura
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Haruhiko Sato
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
| | - Yoshiki Kawabe
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412-8513, Japan
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8
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Gardella TJ, Vilardaga JP. International Union of Basic and Clinical Pharmacology. XCIII. The parathyroid hormone receptors--family B G protein-coupled receptors. Pharmacol Rev 2015; 67:310-37. [PMID: 25713287 DOI: 10.1124/pr.114.009464] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The type-1 parathyroid hormone receptor (PTHR1) is a family B G protein-coupled receptor (GPCR) that mediates the actions of two polypeptide ligands; parathyroid hormone (PTH), an endocrine hormone that regulates the levels of calcium and inorganic phosphate in the blood by acting on bone and kidney, and PTH-related protein (PTHrP), a paracrine-factor that regulates cell differentiation and proliferation programs in developing bone and other tissues. The type-2 parathyroid hormone receptor (PTHR2) binds a peptide ligand, called tuberoinfundibular peptide-39 (TIP39), and while the biologic role of the PTHR2/TIP39 system is not as defined as that of the PTHR1, it likely plays a role in the central nervous system as well as in spermatogenesis. Mechanisms of action at these receptors have been explored through a variety of pharmacological and biochemical approaches, and the data obtained support a basic "two-site" mode of ligand binding now thought to be used by each of the family B peptide hormone GPCRs. Recent crystallographic studies on the family B GPCRs are providing new insights that help to further refine the specifics of the overall receptor architecture and modes of ligand docking. One intriguing pharmacological finding for the PTHR1 is that it can form surprisingly stable complexes with certain PTH/PTHrP ligand analogs and thereby mediate markedly prolonged cell signaling responses that persist even when the bulk of the complexes are found in internalized vesicles. The PTHR1 thus appears to be able to activate the Gα(s)/cAMP pathway not only from the plasma membrane but also from the endosomal domain. The cumulative findings could have an impact on efforts to develop new drug therapies for the PTH receptors.
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Affiliation(s)
- Thomas J Gardella
- Endocrine Unit, Massachusetts General Hospital, Boston, Massachusetts (T.J.G.); and Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (J.-P.V.)
| | - Jean-Pierre Vilardaga
- Endocrine Unit, Massachusetts General Hospital, Boston, Massachusetts (T.J.G.); and Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (J.-P.V.)
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9
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Kumar A, Gopalswamy M, Wishart C, Henze M, Eschen-Lippold L, Donnelly D, Balbach J. N-terminal phosphorylation of parathyroid hormone (PTH) abolishes its receptor activity. ACS Chem Biol 2014; 9:2465-70. [PMID: 25158085 DOI: 10.1021/cb5004515] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The parathyroid hormone (PTH) is an 84-residue peptide, which regulates the blood Ca(2+) level via GPCR binding and subsequent activation of intracellular signaling cascades. PTH is posttranslationally phosphorylated in the parathyroid glands; however, the functional significance of this processes is not well characterized. In the present study, mass spectrometric analysis revealed three sites of phosphorylation, and NMR spectroscopy assigned Ser1, Ser3, and Ser17 as modified sites. These sites are located at the N-terminus of the hormone, which is important for receptor recognition and activation. NMR shows further that the three phosphate groups remotely disturb the α-helical propensity up to Ala36. An intracellular cAMP accumulation assay elucidated the biological significance of this phosphorylation because it ablated the PTH-mediated signaling. Our studies thus shed light on functional implications of phosphorylation at native PTH as an additional level of regulation.
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Affiliation(s)
| | | | - Clare Wishart
- School of
Biomedical Sciences, University of Leeds, Leeds LS2 9JT, U.K
| | | | - Lennart Eschen-Lippold
- Department of Stress and Developmental
Biology, Leibniz Institute of Plant Biochemistry, D-06120 Halle (Saale), Germany
| | - Dan Donnelly
- School of
Biomedical Sciences, University of Leeds, Leeds LS2 9JT, U.K
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10
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Atchison DK, Harding P, Cecilia Ortiz-Capisano M, Peterson EL, Beierwaltes WH. Parathyroid hormone stimulates juxtaglomerular cell cAMP accumulation without stimulating renin release. Am J Physiol Renal Physiol 2012; 303:F1157-65. [PMID: 22896038 DOI: 10.1152/ajprenal.00269.2012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Parathyroid hormone (PTH) is positively coupled to the generation of cAMP via its actions on the PTH1R and PTH2R receptors. Renin secretion from juxtaglomerular (JG) cells is stimulated by elevated intracellular cAMP, and every stimulus that increases renin secretion is thought to do so via increasing cAMP. Thus we hypothesized that PTH increases renin release from primary cultures of mouse JG cells by elevating intracellular cAMP via the PTH1R receptor. We found PTH1R, but not PTH2R, mRNA expressed in JG cells. While PTH increased JG cell cAMP content from (log(10) means ± SE) 3.27 ± 0.06 to 3.92 ± 0.12 fmol/mg protein (P < 0.001), it did not affect renin release. The PTH1R-specific agonist, parathyroid hormone-related protein (PTHrP), also increased JG cell cAMP from 3.13 ± 0.09 to 3.93 ± 0.09 fmol/mg protein (P < 0.001), again without effect on renin release. PTH2R receptor agonists had no effect on cAMP or renin release. PTHrP increased cAMP in the presence of both low and high extracellular calcium from 3.31 ± 0.17 to 3.83 ± 0.20 fmol/mg protein (P < 0.01) and from 3.29 ± 0.18 to 3.63 ± 0.22 fmol/mg protein (P < 0.05), respectively, with no effect on renin release. PTHrP increased JG cell cAMP in the presence of adenylyl cyclase-V inhibition from 2.85 ± 0.17 to 3.44 ± 0.14 fmol/mg protein (P < 0.001) without affecting renin release. As a positive control, forskolin increased JG cell cAMP from 3.39 ± 0.13 to 4.48 ± 0.07 fmol/mg protein (P < 0.01) and renin release from 2.96 ± 0.10 to 3.29 ± 0.08 ng ANG I·mg prot(-1)·h(-1) (P < 0.01). Thus PTH increases JG cell cAMP via non-calcium-sensitive adenylate cyclases without affecting renin release. These data suggest compartmentalization of cAMP signaling in JG cells.
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Affiliation(s)
- Douglas K Atchison
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, 2799 W. Grand Blvd., Detroit, MI 48202, USA
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Dobolyi A, Dimitrov E, Palkovits M, Usdin TB. The neuroendocrine functions of the parathyroid hormone 2 receptor. Front Endocrinol (Lausanne) 2012; 3:121. [PMID: 23060860 PMCID: PMC3465808 DOI: 10.3389/fendo.2012.00121] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 09/20/2012] [Indexed: 01/25/2023] Open
Abstract
The G-protein coupled parathyroid hormone 2 receptor (PTH2R) is concentrated in endocrine and limbic regions in the forebrain. Its endogenous ligand, tuberoinfundibular peptide of 39 residues (TIP39), is synthesized in only two brain regions, within the posterior thalamus and the lateral pons. TIP39-expressing neurons have a widespread projection pattern, which matches the PTH2R distribution in the brain. Neuroendocrine centers including the preoptic area, the periventricular, paraventricular, and arcuate nuclei contain the highest density of PTH2R-positive networks. The administration of TIP39 and an antagonist of the PTH2R as well as the investigation of mice that lack functional TIP39 and PTH2R revealed the involvement of the PTH2R in a variety of neural and neuroendocrine functions. TIP39 acting via the PTH2R modulates several aspects of the stress response. It evokes corticosterone release by activating corticotropin-releasing hormone-containing neurons in the hypothalamic paraventricular nucleus. Block of TIP39 signaling elevates the anxiety state of animals and their fear response, and increases stress-induced analgesia. TIP39 has also been suggested to affect the release of additional pituitary hormones including arginine-vasopressin and growth hormone. A role of the TIP39-PTH2R system in thermoregulation was also identified. TIP39 may play a role in maintaining body temperature in a cold environment via descending excitatory pathways from the preoptic area. Anatomical and functional studies also implicated the TIP39-PTH2R system in nociceptive information processing. Finally, TIP39 induced in postpartum dams may play a role in the release of prolactin during lactation. Potential mechanisms leading to the activation of TIP39 neurons and how they influence the neuroendocrine system are also described. The unique TIP39-PTH2R neuromodulator system provides the possibility for developing drugs with a novel mechanism of action to control neuroendocrine disorders.
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Affiliation(s)
- Arpád Dobolyi
- Neuromorphological and Neuroendocrine Research Laboratory, Department of Anatomy, Histology and Embryology, Hungarian Academy of Sciences, Semmelweis UniversityBudapest, Hungary
- *Correspondence: Arpád Dobolyi, Neuromorphological and Neuroendocrine Research Laboratory, Department of Anatomy, Histology and Embryology, Hungarian Academy of Sciences, Semmelweis University, Tűzoltó u. 58, Budapest H-1094, Hungary. e-mail:
| | - Eugene Dimitrov
- Section on Fundamental Neuroscience, National Institute of Mental Health, National Institute of HealthBethesda, MD, USA
| | - Miklós Palkovits
- Neuromorphological and Neuroendocrine Research Laboratory, Department of Anatomy, Histology and Embryology, Hungarian Academy of Sciences, Semmelweis UniversityBudapest, Hungary
| | - Ted B. Usdin
- Section on Fundamental Neuroscience, National Institute of Mental Health, National Institute of HealthBethesda, MD, USA
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Dobolyi A, Palkovits M, Usdin TB. The TIP39-PTH2 receptor system: unique peptidergic cell groups in the brainstem and their interactions with central regulatory mechanisms. Prog Neurobiol 2010; 90:29-59. [PMID: 19857544 PMCID: PMC2815138 DOI: 10.1016/j.pneurobio.2009.10.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 10/11/2009] [Accepted: 10/14/2009] [Indexed: 01/01/2023]
Abstract
Tuberoinfundibular peptide of 39 residues (TIP39) is the recently purified endogenous ligand of the previously orphan G-protein coupled parathyroid hormone 2 receptor (PTH2R). The TIP39-PTH2R system is a unique neuropeptide-receptor system whose localization and functions in the central nervous system are different from any other neuropeptides. TIP39 is expressed in two brain regions, the subparafascicular area in the posterior thalamus, and the medial paralemniscal nucleus in the lateral pons. Subparafascicular TIP39 neurons seem to divide into a medial and a lateral cell population in the periventricular gray of the thalamus, and in the posterior intralaminar complex of the thalamus, respectively. Periventricular thalamic TIP39 neurons project mostly to limbic brain regions, the posterior intralaminar thalamic TIP39 neurons to neuroendocrine brain areas, and the medial paralemniscal TIP39 neurons to auditory and other brainstem regions, and the spinal cord. The widely distributed axon terminals of TIP39 neurons have a similar distribution as the PTH2R-containing neurons, and their fibers, providing the anatomical basis of a neuromodulatory action of TIP39. Initial functional studies implicated the TIP39-PTH2R system in nociceptive information processing in the spinal cord, in the regulation of different hypophysiotropic neurons in the hypothalamus, and in the modulation of affective behaviors. Recently developed novel experimental tools including mice with targeted mutations of the TIP39-PTH2R system and specific antagonists of the PTH2R will further facilitate the identification of the specific roles of TIP39 and the PTH2R.
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Affiliation(s)
- Arpád Dobolyi
- Department of Anatomy, Histology and Embryology, HAS-Semmelweis University, Budapest, Hungary.
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Parathyroid Hormone and Parathyroid Hormone–Related Peptide in the Regulation of Calcium Homeostasis and Bone Development. Endocrinology 2010. [DOI: 10.1016/b978-1-4160-5583-9.00056-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Brenner D, Bagó AG, Gallatz K, Palkovits M, Usdin TB, Dobolyi A. Tuberoinfundibular peptide of 39 residues in the embryonic and early postnatal rat brain. J Chem Neuroanat 2008; 36:59-68. [PMID: 18495420 DOI: 10.1016/j.jchemneu.2008.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 03/17/2008] [Accepted: 04/09/2008] [Indexed: 11/15/2022]
Abstract
Tuberoinfundibular peptide of 39 residues (TIP39) was identified as the endogenous ligand of parathyroid hormone 2 receptor. We have recently demonstrated that TIP39 expression in adult rat brain is confined to the subparafascicular area of the thalamus with a few cells extending laterally into the posterior intralaminar thalamic nucleus (PIL), and the medial paralemniscal nucleus (MPL) in the lateral pontomesencephalic tegmentum. During postnatal development, TIP39 expression increases until postnatal day 33 (PND-33), then decreases, and almost completely disappears by PND-125. Here, we report the expression of TIP39 during early brain development. TIP39-immunoreactive (TIP39-ir) neurons in the subparafascicular area first appeared at PND-1. In contrast, TIP39-ir neurons were detectable in the MPL at embryonic day 14.5 (ED-14.5), and the intensity of their labeling increased thereafter. We also identified TIP39-ir neurons between ED-16.5 and PND-5 in two additional brain areas, the PIL and the amygdalo-hippocampal transitional zone (AHi). We confirmed the specificity of TIP39 immunolabeling by demonstrating TIP39 mRNA using in situ hybridization histochemistry. In the PIL, TIP39 neurons are located medial to the CGRP group as demonstrated by double immunolabeling. All TIP39-ir neurons in the AHi and most TIP39-ir neurons in the PIL disappear during early postnatal development. The adult pattern of TIP39-ir fibers emerge during postnatal development. However, fibers emanating from PIL can be followed in the supraoptic decussations towards the hypothalamus at ED-18.5. These TIP39-ir fibers disappear by PND-1. The complex pattern of TIP39 expression during early brain development suggests the involvement of TIP39 in transient functions during ontogeny.
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Affiliation(s)
- Dávid Brenner
- Neuromorphological and Neuroendocrine Research Laboratory, Department of Anatomy, Histology and Embryology, Semmelweis University and the Hungarian Academy of Sciences, Budapest H-1094, Hungary
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Dobolyi A, Irwin S, Wang J, Usdin TB. The distribution and neurochemistry of the parathyroid hormone 2 receptor in the rat hypothalamus. Neurochem Res 2006; 31:227-36. [PMID: 16570212 DOI: 10.1007/s11064-005-9011-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2005] [Indexed: 10/24/2022]
Abstract
This study reports the distribution of parathyroid hormone 2 receptor (PTH2R)-immunoreactive fibers in the hypothalamus using fluorescent amplification immunocytochemistry. The pattern of immunolabeling is strikingly similar to that of tuberoinfundibular peptide of 39 residues (TIP39), a peptide recently purified from bovine hypothalamus and proposed to be a ligand of the PTH2R based on pharmacological data. To investigate the anatomical basis of suggestions that TIP39 affects the secretion of several hypophysiotropic hormones we performed double-labeling studies and found that only somatostatin fibers contain PTH2R in the median eminence, which suggests that somatostatin release could be directly regulated via the PTH2R. However, several hypothalamic nuclei projecting to the median eminence contain a high density of both TIP39 and PTH2R fibers and terminals. We report here, that the PTH2R terminals also contain vesicular glutamate transporter-2, and suggest that TIP39 terminals are ideally positioned to modulate glutamatergic influences on hypophysiotropic neurons.
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Affiliation(s)
- Arpád Dobolyi
- Laboratory of Genetics, National Institute of Mental Health, Bethesda, MD 20892, USA
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Murray TM, Rao LG, Divieti P, Bringhurst FR. Parathyroid hormone secretion and action: evidence for discrete receptors for the carboxyl-terminal region and related biological actions of carboxyl- terminal ligands. Endocr Rev 2005; 26:78-113. [PMID: 15689574 DOI: 10.1210/er.2003-0024] [Citation(s) in RCA: 230] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PTH is a major systemic regulator of the concentrations of calcium, phosphate, and active vitamin D metabolites in blood and of cellular activity in bone. Intermittently administered PTH and amino-terminal PTH peptide fragments or analogs also augment bone mass and currently are being introduced into clinical practice as therapies for osteoporosis. The amino-terminal region of PTH is known to be both necessary and sufficient for full activity at PTH/PTHrP receptors (PTH1Rs), which mediate the classical biological actions of the hormone. It is well known that multiple carboxyl-terminal fragments of PTH are present in blood, where they comprise the major form(s) of circulating hormone, but these fragments have long been regarded as inert by-products of PTH metabolism because they neither bind to nor activate PTH1Rs. New in vitro and in vivo evidence, together with older observations extending over the past 20 yr, now points strongly to the existence of novel large carboxyl-terminal PTH fragments in blood and to receptors for these fragments that appear to mediate unique biological actions in bone. This review traces the development of this field in the context of the evolution of our understanding of the "classical" receptor for amino-terminal PTH and the now convincing evidence for these receptors for carboxyl-terminal PTH. The review summarizes current knowledge of the structure, secretion, and metabolism of PTH and its circulating fragments, details available information concerning the pharmacology and actions of carboxyl-terminal PTH receptors, and frames their likely biological and clinical significance. It seems likely that physiological parathyroid regulation of calcium and bone metabolism may involve receptors for circulating carboxy-terminal PTH ligands as well as the action of amino-terminal determinants within the PTH molecule on the classical PTH1R.
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Affiliation(s)
- Timothy M Murray
- Department of Medicine, University of Toronto, and the Division of Endocrinology and Metabolism, St. Michael's Hospital, Toronto, Ontario, Canada.
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Papasani MR, Gensure RC, Yan YL, Gunes Y, Postlethwait JH, Ponugoti B, John MR, Jüppner H, Rubin DA. Identification and characterization of the zebrafish and fugu genes encoding tuberoinfundibular peptide 39. Endocrinology 2004; 145:5294-304. [PMID: 15297442 DOI: 10.1210/en.2004-0159] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although the PTH type 2 receptor (PTH2R) has been isolated from mammals and zebrafish, only its mammalian agonist, tuberoinfundibular peptide 39 (TIP39), has been characterized thus far. To determine whether zebrafish TIP39 (zTIP39) functions similarly with the zebrafish PTHR (zPTH2R) and human PTH2Rs and to determine its tissue-specific expression, fugu (Takifugu rubripes) and zebrafish (Danio rerio) genomic databases were screened with human TIP39 (hTIP39) sequences. A single TIP39 gene was identified for each fish species, which showed significant homology to mammalian TIP39. Using standard molecular techniques, we isolated cDNA sequences encoding zTIP39. The fugu TIP39 precursor was encoded by a gene comprising at least three exons. It contained a hydrophobic signal sequence and a predicted prosequence with a dibasic cleavage site, similar to that found in mammalian TIP39 ligands. Phylogenetic analyses suggested that TIP39 forms the basal group from which PTH and PTHrP have been derived. Functionally, subtle differences in potency could be discerned between hTIP39 and zTIP39. The human PTH2R and zPTH2R were stimulated slightly better by both hTIP39 and zTIP39, whereas zTIP39 had a higher potency at a previously isolated zPTH2R splice variant. Whole-mount in situ hybridization of zebrafish revealed strong zTIP39 expression in the region of the hypothalamus and in the heart of 24- and 48-h-old embryos. Similarly, zPTH2R expression was highly expressed throughout the brain of 48- and 72-h-old embryos. Because the mammalian PTH2R was also most abundantly expressed in these tissues, the TIP39-PTH2R system may serve conserved physiological roles in mammals and fishes.
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Affiliation(s)
- Madhusudhan R Papasani
- Department of Biological Sciences, Illinois State University, Normal, Illinois 61790, USA
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Gensure RC, Ponugoti B, Gunes Y, Papasani MR, Lanske B, Bastepe M, Rubin DA, Jüppner H. Identification and characterization of two parathyroid hormone-like molecules in zebrafish. Endocrinology 2004; 145:1634-9. [PMID: 14684608 DOI: 10.1210/en.2003-0964] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Zebrafish (Danio rerio) have receptors homologous to the human PTH (hPTH)/PTHrP receptor (PTH1R) and PTH-2 receptor (PTH2R) and an additional receptor (PTH3R) with high homology to the PTH1R. To find natural ligands for zPTH1R and zPTH3R, we searched the zebrafish genomic database and discovered two distinct regions that, when translated (zPTH1 and zPTH2), showed high homology to hPTH. Isolation of cDNAs and determination of the intron/exon boundaries revealed genomic structures which were similar to known PTHs. Peptides consisting of the first 34 amino acids after the pre- and prosequences of the zebrafish PTHs (zPTHs) were synthesized and were shown to be fully active at the hPTH1R. zPTH2(1-34) was, however, approximately 30-fold less potent at the zPTH1R than hPTH(1-34), hPTHrP(1-36), and zPTH1(1-34). When tested with zPTH3R, zPTH1(1-34) and hPTHrP(1-36) showed similar potencies, whereas the potency of zPTH2(1-34) was moderately (3-fold) reduced. To determine whether other fishes have multiple PTHs, we searched the genomic database of the Japanese pufferfish (Takifugu rubripes) and identified zPTH1 and zPTH2 homologs. Phylogenetic analysis showed that PTHs from zebrafish and pufferfish are more closely related to each other than to known mammalian PTH homologs or to PTHrP and tuberoinfundibular peptide of 39 residues. This is consistent with evolution of two teleost PTH-like peptides occurring after the evolutionary divergence between fishes and mammals. Overall, the PTH system appears more complex in fishes than in mammals, providing evidence of continued evolution in nontetrapod species. The availability of multiple forms of fish PTH and their receptors provide additional tools for PTH ligand/receptor structure-function studies.
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Affiliation(s)
- Robert C Gensure
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA
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Tobias JH, Cooper C. PTH/PTHrP activity and the programming of skeletal development in utero. J Bone Miner Res 2004; 19:177-82. [PMID: 14969386 DOI: 10.1359/jbmr.0301235] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2003] [Accepted: 11/17/2003] [Indexed: 11/18/2022]
Abstract
There is increasing evidence that nutritional deficiency in utero adversely affects bone development and the risk of developing osteoporosis in later life. Although the mechanisms involved are unknown, circumstantial evidence points to an important role of PTH/PTHrP activity. It is recognized that PTH and PTHrP are critically involved in regulating fetal calcium homeostasis, actions that are mediated at least in part by PPR. As well as playing a central role in the maintenance of calcium homeostasis in the fetus, studies in transgenic mice show that PTH, PTHrP, and PPR exert similar effects on skeletal development in utero, acting to increase the size of the trabecular envelope and decrease that of the cortical envelopes. Taken together, these observations raise the possibility that stimulation of PTH/PTHrP activity in the fetus in response to calcium deficiency acts to increase the size of the trabecular envelope but to reduce that of the cortical envelope. Although any increase in trabecular bone at birth is likely to be relatively transient, a decrease in size of the cortical envelope may have a persistent effect on the trajectory of bone growth in subsequent childhood. Consistent with this proposal, preliminary findings from birth cohort studies suggest that maternal calcium intake and cord blood calcium levels are positively related to bone mass of the offspring as assessed later in childhood. Further studies are justified to determine whether alterations in fetal PTH/ PTHrP activity caused by calcium stress lead to a reduction in size of the cortical envelope at birth that persists into childhood and later adult life and to identify modifiable maternal factors that are responsible for these changes.
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Affiliation(s)
- Jonathan H Tobias
- Department of Clinical Sciences at South Bristol, University of Bristol, Bristol, United Kingdom.
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Sugimura Y, Murase T, Ishizaki S, Tachikawa K, Arima H, Miura Y, Usdin TB, Oiso Y. Centrally administered tuberoinfundibular peptide of 39 residues inhibits arginine vasopressin release in conscious rats. Endocrinology 2003; 144:2791-6. [PMID: 12810532 DOI: 10.1210/en.2002-0017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tuberoinfundibular peptide of 39 residues (TIP39) is a recently discovered neuropeptide identified on the basis of its ability to activate the PTH2 receptor, and it is thought to be the brain PTH2 receptor's endogenous ligand. The PTH2 receptor is highly expressed in the hypothalamus, suggesting a role in the modulation of neuroendocrinological functions. PTHrP, which also belongs to the PTH-related peptides family, stimulates arginine vasopressin (AVP) release. In the present study, therefore, we investigated the effect of centrally administered TIP39 on AVP release in conscious rats. Intracerebroventricular administration of TIP39 (10-500 pmol/rat) significantly suppressed the plasma AVP concentration in dehydrated rats, and the maximum effect was obtained 5 min after administration (dehydration with 100 pmol/rat TIP39, 4.32 +/- 1.17 pg/ml; vs. control, 8.21 +/- 0.70 pg/ml). The plasma AVP increase in response to either hyperosmolality [ip injection of hypertonic saline (HS), 600 mosmol/kg] or hypovolemia [ip injection of polyethylene glycol (PEG)] was also significantly attenuated by an intracerebroventricular injection of TIP39 (HS with 100 pmol/rat TIP39, 2.65 +/- 0.52 pg/ml; vs. HS alone, 4.69 +/- 0.80 pg/ml; PEG with 100 pmol/rat TIP39, 4.10 +/- 0.79 pg/ml; vs. PEG alone, 6.19 +/- 0.34 pg/ml). Treatment with naloxone [1.5 mg/rat, sc injection], a nonselective opioid receptor antagonist, significantly reversed the inhibitory effects of TIP39 on AVP release. These results suggest that central TIP39 plays an inhibitory role in the osmoregulation and baroregulation of AVP release and that intrinsic opioid systems are involved in its mechanism.
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Affiliation(s)
- Yoshihisa Sugimura
- Department of Internal Medicine, Graduate School of Medicine, Nagoya University, Nagoya, Aichi 466-8550, Japan
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Dobolyi A, Palkovits M, Usdin TB. Expression and distribution of tuberoinfundibular peptide of 39 residues in the rat central nervous system. J Comp Neurol 2003; 455:547-66. [PMID: 12508326 DOI: 10.1002/cne.10515] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Tuberoinfundibular peptide of 39 residues (TIP39) has been recently purified and identified as a selective ligand for the parathyroid hormone 2 receptor. As a next step toward understanding its functions, we report the expression and distribution of TIP39 in the rat central nervous system. In situ hybridization histochemistry and immunocytochemistry revealed TIP39-containing cell bodies in three distinct areas. The major one comprises the subparafascicular area posterior through the intralaminar nucleus of the thalamus; a second is the medial paralemniscal nucleus at the pontomesencephalic junction; and a third is in the dorsal and dorsolateral hypothalamic areas, which contained a few, scattered cell bodies. We found, in contrast to the highly restricted localization of TIP39-containing cell bodies, a much more widespread localization of TIP39-containing fibers. The highest density of fibers was observed in limbic areas such as the septum, the amygdala, and the bed nucleus of the stria terminalis; in areas involved in endocrine regulation, such as the hypothalamic dorsomedial, paraventricular, periventricular, and arcuate nuclei; in auditory areas, such as the ectorhinal and temporal cortices, inferior colliculus, medial geniculate body, and some of the nuclei of the superior olivary complex; and in the dorsolateral funiculus of the spinal cord. The localization of TIP39-containing nuclei and fibers provides an anatomical basis for previously demonstrated endocrine and nociceptive effects of TIP39 and suggests additional functions for TIP39, one apparent candidate being the regulation of auditory information processing.
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Affiliation(s)
- Arpad Dobolyi
- Laboratory of Genetics, National Institute of Mental Health, Bethesda, Maryland 20892-4094, USA
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Goodman WG, Jüppner H, Salusky IB, Sherrard DJ. Parathyroid hormone (PTH), PTH-derived peptides, and new PTH assays in renal osteodystrophy. Kidney Int 2003; 63:1-11. [PMID: 12472763 DOI: 10.1046/j.1523-1755.2003.00700.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Parathyroid hormone (PTH), PTH-derived peptides, and new PTH assays in renal osteodystrophy. Reliable measurements of parathyroid hormone (PTH) concentrations in serum or plasma are critical for the appropriate diagnosis and management of patients with renal osteodystrophy. With the introduction of second generation immunometric assays for PTH, it is now possible to measure exclusively full-length, biologically active PTH(1-84). In contrast, first generation immunometric assays that have been used widely for many years detect not only PTH(1-84), but also other large amino-terminally-truncated, PTH-derived peptides. This development will require a careful re-evaluation of PTH measurements, as determined by either first or second generation immunometric assays, and their relationship to bone histology and bone remodeling rates in patients with end-stage renal disease (ESRD). Such information is essential for proper clinical management, but only limited bone biopsy data are available to guide the interpretation of PTH results using second generation PTH assays. The different performance characteristics of first and second generation immunometric PTH assays also makes it possible to quantify the plasma levels of amino-terminally-truncated, PTH-derived peptides, which may accumulate disproportionately in patients with ESRD. Recent experimental evidence indicates that one or more of these peptides can modify bone cell activity and skeletal remodeling, possibly by interacting with a PTH receptor distinct from the type I PTH receptor that binds to the amino-terminal portion of PTH and mediates the classical biological actions of the hormone. The putative C-PTH receptor interacts with mid- and/or carboxyterminal regions of PTH and other amino-terminally-truncated PTH-derived peptides; signaling through it may contribute to the skeletal resistance to PTH that characterizes ESRD. The current review discusses certain aspects of the molecular structure of PTH and its interaction with various receptors, briefly comments about selected components of PTH secretion, highlights recent technical advances in PTH assays, and summarizes the effects of various PTH-derived peptides on bone cells and on skeletal metabolism.
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Affiliation(s)
- William G Goodman
- Department of Medicine, UCLA School of Medicine, Los Angeles, California 90095, USA.
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John MR, Arai M, Rubin DA, Jonsson KB, Jüppner H. Identification and characterization of the murine and human gene encoding the tuberoinfundibular peptide of 39 residues. Endocrinology 2002; 143:1047-57. [PMID: 11861531 DOI: 10.1210/endo.143.3.8698] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
By screening public databases, we identified human and mouse genomic DNA clones that encode the tuberoinfundibular peptide of 39 residues (TIP39). The TIP39 precursor is encoded by at least three exons; a noncoding exon U1, exon 1 encoding residues -61 (initiator methionine) to -19 of the leader sequence, and exon 2 encoding residues -18 to -1 and residues +1 to +39. Secreted human TIP39 is identical to the previously isolated bovine TIP39, whereas mouse TIP39 differs by four amino acids. Phylogenetic analyses suggested that TIP39, PTH, and PTHrP may have evolved from a common ancestor. Synthetic human and mouse TIP39 showed indistinguishable potencies [EC(50): 0.54 (human) vs. 0.74 nM (mouse)] at the human PTH2-receptor stably expressed in LLCPK(1) cells; furthermore, TIP-(9-39) was an inhibitor of cAMP accumulation stimulated by either [Tyr(34)]PTH(1-34)amide or human/bovine TIP39. In the mouse, an approximately 4.5-kb mRNA encoding TIP39 was identified by Northern blot analysis in testis and, less abundantly, in liver and kidney, whereas other tissues revealed additional smaller transcripts. In situ hybridizations revealed TIP39 expression in seminiferous tubuli and several brain regions, including nucleus ruber, nucleus centralis pontis, and nucleus subparafascicularis thalami. Because PTH2 receptor expression was previously shown to be highest in brain, pancreas, and testis, our findings are consistent with the notion that TIP39 is a neuropeptide which may also have a role in spermatogenesis.
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Affiliation(s)
- Markus R John
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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Dobolyi A, Ueda H, Uchida H, Palkovits M, Usdin TB. Anatomical and physiological evidence for involvement of tuberoinfundibular peptide of 39 residues in nociception. Proc Natl Acad Sci U S A 2002; 99:1651-6. [PMID: 11818570 PMCID: PMC122245 DOI: 10.1073/pnas.042416199] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The parathyroid hormone 2 (PTH2) receptor's anatomical distribution suggests that, among other functions, it may be involved in modulation of nociception. We localized PTH2 receptor protein to spinal cord lamina II and showed that it is synthesized by subpopulations of primary sensory neurons and intrinsic spinal cord dorsal horn neurons. Tuberoinfundibular peptide of 39 residues (TIP39) selectively activates the PTH2 receptor. Intraplantar microinjection of TIP39 caused a paw-withdrawal response and intrathecal injection caused scratching, biting, and licking, a nocifensive response. Intrathecal administration of a TIP39 antibody decreased sensitivity in tail-flick and paw-pressure assays. Intrathecal administration of TIP39 potentiated responses in these assays. We determined the sequence of TIP39's precursor and found that mRNA encoding TIP39 and TIP39-like immunoreactivity is concentrated in two brainstem areas, the subparafascicular area and the caudal paralemniscal nucleus. Cells in these areas project to the superficial dorsal horn of the spinal cord. Our data suggest that TIP39 released from supraspinal fibers potentiates aspects of nociception within the spinal cord.
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Affiliation(s)
- Arpad Dobolyi
- Laboratory of Genetics, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
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Ward HL, Small CJ, Murphy KG, Kennedy AR, Ghatei MA, Bloom SR. The actions of tuberoinfundibular peptide on the hypothalamo-pituitary axes. Endocrinology 2001; 142:3451-6. [PMID: 11459790 DOI: 10.1210/endo.142.8.8308] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tuberoinfundibular peptide is a recently discovered agonist for the PTH receptor-2; the latter has a wide distribution including the external zone of the median eminence of the hypothalamus, suggesting a role in neuroendocrine function. We have investigated the effects of tuberoinfundibular peptide on the hypothalamo-pituitary axes in vitro and in vivo. Tuberoinfundibular peptide had effects on the hypothalamo-pituitary-adrenal axis with increased release of ACTH-releasing factor (tuberoinfundibular peptide 100 nM 4.4 +/- 0.6 pmol/explant vs. control 2.9 +/- 0.4 pmol/explant, P < 0.001) and increased release of arginine vasopressin (tuberoinfundibular peptide 100 nM 563.5 +/- 55.5 fmol/explant vs. control 73.4 +/- 9.6 fmol/explant, P < 0.01) from in vitro hypothalamic explants. Intracerebroventricular administration of tuberoinfundibular peptide and PTH((1-34)) resulted in elevated plasma ACTH at 10 min post injection (saline 13.5 +/- 2.1 pg/ml, tuberoinfundibular peptide 3 nmol 32.3 +/- 4.0 pg/ml; P < 0.01 to saline: PTH((1-34)) 10 nmol 28.9 +/- 3.2 pg/ml: P < 0.05 to saline). Tuberoinfundibular peptide also had both in vitro and in vivo effects on the hypothalamo-pituitary-gonadal axis with increased release of LH-releasing hormone (tuberoinfundibular peptide 100 nM 28.5 +/- 5.1 fmol/explant vs. control 19.3 +/- 2.5 fmol/explant, P < 0.05) from in vitro hypothalamic explants. Both intracerebroventricular and peripheral administration of tuberoinfundibular peptide had effects on the hypothalamo-pituitary-gonadal axis. Intracerebroventricular injection of tuberoinfundibular peptide increased plasma LH (tuberoinfundibular peptide 10 nmol 0.70 +/- 0.09 ng/ml vs. saline 0.42 +/- 0.04 ng/ml at 10 min, P < 0.05). Intraperitoneal administration of tuberoinfundibular peptide also increased plasma LH (tuberoinfundibular peptide 30 nmol 0.53 +/- 0.09 ng/ml vs. saline 0.21 +/- 0.04 ng/ml at 10 min, P < 0.05). In addition to these actions on the hypothalamo-pituitary-adrenal and hypothalamo-pituitary-gonadal axes, an increased release of GH-releasing factor (GRF) from hypothalamic explants (tuberoinfundibular peptide 100 nM 770.9 +/- 90.7 pg/explant vs. control 657.8 +/- 77.7 pg/explant, P < 0.01) was observed. Overall, these data show the actions of tuberoinfundibular peptide on the hypothalamo-pituitary axes and suggest that it may play a role in the control of the hypothalamo-pituitary-adrenal and hypothalamo-pituitary-gonadal axes.
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Affiliation(s)
- H L Ward
- Metabolic Medicine, Endocrine Unit, Imperial College School of Medicine, Hammersmith Hospital, London, United Kingdom W12 ONN
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Jonsson KB, John MR, Gensure RC, Gardella TJ, Jüppner H. Tuberoinfundibular peptide 39 binds to the parathyroid hormone (PTH)/PTH-related peptide receptor, but functions as an antagonist. Endocrinology 2001; 142:704-9. [PMID: 11159842 DOI: 10.1210/endo.142.2.7945] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The tuberoinfundibular peptide TIP39 [TIP-(1-39)], which exhibits only limited amino acid sequence homology with PTH and PTH-related peptide (PTHrP), stimulates cAMP accumulation in cells expressing the PTH2 receptor (PTH2R), but it is inactive at the PTH/PTHrP receptor (PTH1R). However, when using either (125)I-labeled rat [Nle(8,21),Tyr(34)]PTH-(1-34)amide (rPTH) or (125)I-labeled human [Tyr(36)]PTHrP-(1-36)amide [PTHrP-(1-36)] for radioreceptor studies, TIP-(1-39) bound to LLCPK(1) cells stably expressing the PTH1R (HKrk-B7 cells), albeit with weak apparent affinity (243 +/- 52 and 210 +/- 64 nM, respectively). In comparison to the parent peptide, the apparent binding affinity of TIP-(3-39) was about 3-fold higher, and that of TIP-(9-39) was about 5.5-fold higher. However, despite their improved IC(50) values at the PTH1R, both truncated peptides failed to stimulate cAMP accumulation in HKrk-B7 cells. In contrast, the chimeric peptide PTHrP-(1-20)/TIP-(23-39) bound to HKrk-B7 cells with affinities of 31 +/- 8.2 and 11 +/- 4.0 nM when using radiolabeled rPTH and PTHrP-(1-36), respectively, and it stimulated cAMP accumulation in HKrk-B7 and SaOS-2 cells with potencies (EC(50), 1.40 +/- 0.3 and 0.38 +/- 0.12 nM, respectively) and efficacies (maximum levels, 39 +/- 8 and 31 +/- 3 pmol/well, respectively) similar to those of PTH-(1-34) and PTHrP-(1-36). In both cell lines, TIP(9-39) and, to a lesser extent, TIP-(1-39) inhibited the actions of the three agonists with efficiencies similar to those of [Leu(11),D-Trp(12),Trp(23),Tyr(36)]PTHrP-(7-36)amide, an established PTH1R antagonist. Taken together, the currently available data suggest that the carboxyl-terminal portion of TIP-(1-39) interacts efficiently with the PTH1R, at sites identical to or closely overlapping those used by PTH-(1-34) and PTHrP-(1-36). The amino-terminal residues of TIP-(1-39), however, are unable to interact productively with the PTH1R, thus enabling TIP-(1-39) and some of its truncated analogs to function as an antagonist at this receptor.
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Affiliation(s)
- K B Jonsson
- Endocrine Unit, Department of Medicine and Pediatric Endocrine Unit MassGeneral Hospital for Children, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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Affiliation(s)
- T J Gardella
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Usdin TB, Wang T, Hoare SR, Mezey E, Palkovits M. New members of the parathyroid hormone/parathyroid hormone receptor family: the parathyroid hormone 2 receptor and tuberoinfundibular peptide of 39 residues. Front Neuroendocrinol 2000; 21:349-83. [PMID: 11013069 DOI: 10.1006/frne.2000.0203] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The parathyroid hormone (PTH) family currently includes three peptides and three receptors. PTH regulates calcium homeostasis through bone and kidney PTH1 receptors. PTH-related peptide, probably also through PTH1 receptors, regulates skeletal, pancreatic, epidermal, and mammary gland differentiation and bladder and vascular smooth muscle relaxation and has a CNS role that is under investigation. Tuberoinfundibular peptide of 39 residues (TIP39) was recently purified from bovine hypothalamus based on selective PTH2 receptor activation. PTH2 receptor expression is greatest in the CNS, where it is concentrated in limbic, hypothalamic, and sensory areas, especially hypothalamic periventricular neurons, nerve terminals in the median eminence, superficial layers of the spinal cord dorsal horn, and the caudal part of the sensory trigeminal nucleus. It is also present in a number of endocrine cells. Thus TIP39 and PTH2 receptor-influenced functions may range from pituitary and pancreatic hormone release to pain perception. A third PTH-recognizing receptor has been found in zebrafish.
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Affiliation(s)
- T B Usdin
- Laboratory of Genetics, National Institute of Mental Health, Bethesda, Maryland 20892-4094, USA.
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Hoare SR, Rubin DA, Jüppner H, Usdin TB. Evaluating the ligand specificity of zebrafish parathyroid hormone (PTH) receptors: comparison of PTH, PTH-related protein, and tuberoinfundibular peptide of 39 residues. Endocrinology 2000; 141:3080-6. [PMID: 10965877 DOI: 10.1210/endo.141.9.7645] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Homologs of mammalian PTH1 and PTH2 receptors, and a novel PTH3 receptor have been identified in zebrafish (zPTH1, zPTH2, and zPTH3). zPTH1 receptor ligand specificity is similar to that of mammalian PTH1 receptors. The zPTH2 receptor is selective for PTH over PTH-related protein (PTHrP); however, PTH produces only modest cAMP accumulation. A PTH2 receptor-selective peptide, tuberoinfundibular peptide of 39 residues (TIP39), has recently been purified from bovine hypothalamus. The effect of TIP39 has not previously been examined on zebrafish receptors. The zPTH3 receptor was initially described as PTHrP selective based on comparison with the effects of human PTH. We have now examined the ligand specificity of the zebrafish PTH-recognizing receptors expressed in COS-7 cells using a wide range of ligands. TIP39 is a potent agonist for stimulation of cAMP accumulation at two putative splice variants of the zPTH2 receptor (EC50, 2.6 and 5.2 nM); in comparison, PTH is a partial agonist [maximal effect (Emax) of PTH peptides ranges from 28-49% of the TIP39 Emax]. As TIP39 is much more efficacious than any known PTH-like peptide, a homolog of TIP39 may be the zPTH2 receptor's endogenous ligand. At the zPTH3 receptor, rat PTH-(1-34) and rat PTH-(1-84) (EC50, 0.22 and 0.45 nM) are more potent than PTHrP (EC50, 1.5 nM), and rPTH-(1-34) binds with high affinity (3.2 nM). PTH has not been isolated from fish. PTHrP-like peptides, which have been identified in fish, may be the natural ligands for zPTH1 and zPTH3 receptors.
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Affiliation(s)
- S R Hoare
- Laboratory of Genetics, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-4094, USA
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Hoare SR, Clark JA, Usdin TB. Molecular Determinants of Tuberoinfundibular Peptide of 39 Residues (TIP39) Selectivity for the Parathyroid Hormone-2 (PTH2) Receptor. J Biol Chem 2000. [DOI: 10.1016/s0021-9258(19)61507-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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