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Robayo-Amortegui H, Quintero-Altare A, Florez-Navas C, Serna-Palacios I, Súarez-Saavedra A, Buitrago-Bernal R, Casallas-Barrera JO. Fluid dynamics of life: exploring the physiology and importance of water in the critical illness. Front Med (Lausanne) 2024; 11:1368502. [PMID: 38745736 PMCID: PMC11092983 DOI: 10.3389/fmed.2024.1368502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 04/12/2024] [Indexed: 05/16/2024] Open
Abstract
Water acknowledged as a vital component for life and the universal solvent, is crucial for diverse physiological processes in the human body. While essential for survival, the human body lacks the capacity to produce water, emphasizing the need for regular ingestion to maintain a homeostatic environment. The human body, predominantly composed of water, exhibits remarkable biochemical properties, playing a pivotal role in processes such as protein transport, thermoregulation, the cell cycle, and acid–base balance. This review delves into comprehending the molecular characteristics of water and its interactions within the human body. The article offers valuable insights into the intricate relationship between water and critical illness. Through a comprehensive exploration, it seeks to enhance our understanding of water’s pivotal role in sustaining overall human health.
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Affiliation(s)
- Henry Robayo-Amortegui
- Department of Critical Care Medicine, Fundación Clínica Shaio, Bogotá, DC, Colombia
- Department of Medicine, Critical Care Resident, Universidad de La Sabana, Chía Cundinamarca, Colombia
| | - Alejandro Quintero-Altare
- Department of Critical Care Medicine, Fundación Clínica Shaio, Bogotá, DC, Colombia
- Department of Medicine, Critical Care Resident, Universidad de La Sabana, Chía Cundinamarca, Colombia
| | - Catalina Florez-Navas
- Department of Critical Care Medicine, Fundación Clínica Shaio, Bogotá, DC, Colombia
- Department of Medicine, Critical Care Resident, Universidad de La Sabana, Chía Cundinamarca, Colombia
| | - Isacio Serna-Palacios
- Department of Medicine, Critical Care Resident, Universidad de La Sabana, Chía Cundinamarca, Colombia
| | | | - Ricardo Buitrago-Bernal
- Department of Critical Care Medicine, Fundación Clínica Shaio, Bogotá, DC, Colombia
- Exploratorium group, Fundación Clínica Shaio, Bogotá, DC, Colombia
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2
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Mishra S, Grewal J, Wal P, Bhivshet GU, Tripathi AK, Walia V. Therapeutic potential of vasopressin in the treatment of neurological disorders. Peptides 2024; 174:171166. [PMID: 38309582 DOI: 10.1016/j.peptides.2024.171166] [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: 10/19/2023] [Revised: 01/18/2024] [Accepted: 01/29/2024] [Indexed: 02/05/2024]
Abstract
Vasopressin (VP) is a nonapeptide made of nine amino acids synthesized by the hypothalamus and released by the pituitary gland. VP acts as a neurohormone, neuropeptide and neuromodulator and plays an important role in the regulation of water balance, osmolarity, blood pressure, body temperature, stress response, emotional challenges, etc. Traditionally VP is known to regulate the osmolarity and tonicity. VP and its receptors are widely expressed in the various region of the brain including cortex, hippocampus, basal forebrain, amygdala, etc. VP has been shown to modulate the behavior, stress response, circadian rhythm, cerebral blood flow, learning and memory, etc. The potential role of VP in the regulation of these neurological functions have suggested the therapeutic importance of VP and its analogues in the management of neurological disorders. Further, different VP analogues have been developed across the world with different pharmacotherapeutic potential. In the present work authors highlighted the therapeutic potential of VP and its analogues in the treatment and management of various neurological disorders.
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Affiliation(s)
- Shweta Mishra
- SGT College of Pharmacy, SGT University, Gurugram, India
| | - Jyoti Grewal
- Maharisi Markandeshwar University, Sadopur, India
| | - Pranay Wal
- Pranveer Singh Institute of Pharmacy, Kanpur, India
| | | | | | - Vaibhav Walia
- SGT College of Pharmacy, SGT University, Gurugram, India.
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3
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Bous J, Fouillen A, Orcel H, Granier S, Bron P, Mouillac B. Structures of the arginine-vasopressin and oxytocin receptor signaling complexes. VITAMINS AND HORMONES 2023; 123:67-107. [PMID: 37718002 DOI: 10.1016/bs.vh.2022.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Arginine-vasopressin (AVP) and oxytocin (OT) are neurohypophysial hormones which share a high sequence and structure homology. These are two cyclic C-terminally amidated nonapeptides with different residues at position 3 and 8. In mammals, AVP and OT exert their multiple biological functions through a specific G protein-coupled receptor family: four receptors are identified, the V1a, V1b, V2 receptors (V1aR, V1bR and V2R) and the OT receptor (OTR). The chemical structure of AVP and OT was elucidated in the early 1950s. Thanks to X-ray crystallography and cryo-electron microscopy, it took however 70 additional years to determine the three-dimensional structures of the OTR and the V2R in complex with their natural agonist ligands and with different signaling partners, G proteins and β-arrestins. Today, the comparison of the different AVP/OT receptor structures gives structural insights into their orthosteric ligand binding pocket, their molecular mechanisms of activation, and their interfaces with canonical Gs, Gq and β-arrestin proteins. It also paves the way to future rational drug design and therapeutic compound development. Indeed, agonist, antagonist, biased agonist, or pharmacological chaperone analogues of AVP and OT are promising candidates to regulate different physiological functions and treat several pathologies.
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Affiliation(s)
- Julien Bous
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Aurélien Fouillen
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Hélène Orcel
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Sébastien Granier
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Patrick Bron
- CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Bernard Mouillac
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.
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4
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Bous J, Fouillen A, Orcel H, Trapani S, Cong X, Fontanel S, Saint-Paul J, Lai-Kee-Him J, Urbach S, Sibille N, Sounier R, Granier S, Mouillac B, Bron P. Structure of the vasopressin hormone-V2 receptor-β-arrestin1 ternary complex. SCIENCE ADVANCES 2022; 8:eabo7761. [PMID: 36054364 PMCID: PMC10866553 DOI: 10.1126/sciadv.abo7761] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
Arrestins interact with G protein-coupled receptors (GPCRs) to stop G protein activation and to initiate key signaling pathways. Recent structural studies shed light on the molecular mechanisms involved in GPCR-arrestin coupling, but whether this process is conserved among GPCRs is poorly understood. Here, we report the cryo-electron microscopy active structure of the wild-type arginine-vasopressin V2 receptor (V2R) in complex with β-arrestin1. It reveals an atypical position of β-arrestin1 compared to previously described GPCR-arrestin assemblies, associated with an original V2R/β-arrestin1 interface involving all receptor intracellular loops. Phosphorylated sites of the V2R carboxyl terminus are clearly identified and interact extensively with the β-arrestin1 N-lobe, in agreement with structural data obtained with chimeric or synthetic systems. Overall, these findings highlight a notable structural variability among GPCR-arrestin signaling complexes.
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Affiliation(s)
- Julien Bous
- CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Aurélien Fouillen
- CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Hélène Orcel
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Stefano Trapani
- CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Xiaojing Cong
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Simon Fontanel
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Julie Saint-Paul
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Joséphine Lai-Kee-Him
- CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Serge Urbach
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Nathalie Sibille
- CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Rémy Sounier
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Sébastien Granier
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Bernard Mouillac
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
| | - Patrick Bron
- CBS (Centre de Biologie Structurale), Université de Montpellier, CNRS, INSERM, Montpellier, France
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5
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Clarke L, Zyga O, Pineo-Cavanaugh PL, Jeng M, Fischbein NJ, Partap S, Katznelson L, Parker KJ. Socio-behavioral dysfunction in disorders of hypothalamic-pituitary involvement: The potential role of disease-induced oxytocin and vasopressin signaling deficits. Neurosci Biobehav Rev 2022; 140:104770. [PMID: 35803395 PMCID: PMC10999113 DOI: 10.1016/j.neubiorev.2022.104770] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 06/16/2022] [Accepted: 07/02/2022] [Indexed: 10/17/2022]
Abstract
Disorders involving hypothalamic and pituitary (HPIT) structures-including craniopharyngioma, Langerhans cell histiocytosis, and intracranial germ cell tumors-can disrupt brain and endocrine function. An area of emerging clinical concern in patients with these disorders is the co-occurring socio-behavioral dysfunction that persists after standard hormone replacement therapy. Although the two neuropeptides most implicated in mammalian social functioning (oxytocin and arginine vasopressin) are of hypothalamic origin, little is known about how disease-induced damage to HPIT structures may disrupt neuropeptide signaling and, in turn, impact patients' socio-behavioral functioning. Here we provide a clinical primer on disorders of HPIT involvement and a review of neuropeptide signaling and socio-behavioral functioning in relevant animal models and patient populations. This collective evidence suggests that neuropeptide signaling disruptions contribute to socio-behavioral deficits experienced by patients with disorders of HPIT involvement. A better understanding of the biological underpinnings of patients' socio-behavioral symptoms is now needed to enable the development of the first targeted pharmacological strategies by which to manage patients' socio-behavioral dysfunction.
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Affiliation(s)
- Lauren Clarke
- Department of Psychiatry and Behavioral Sciences, Stanford University, 1201 Welch Road, MSLS P-104, Stanford, CA 94305, USA
| | - Olena Zyga
- Department of Psychiatry and Behavioral Sciences, Stanford University, 1201 Welch Road, MSLS P-104, Stanford, CA 94305, USA
| | - Psalm L Pineo-Cavanaugh
- Department of Psychiatry and Behavioral Sciences, Stanford University, 1201 Welch Road, MSLS P-104, Stanford, CA 94305, USA
| | - Michael Jeng
- Department of Pediatrics (Hematology/Oncology Division), Stanford University, 1000 Welch Road, Suite 300, Palo Alto, CA 94304, USA
| | - Nancy J Fischbein
- Department of Radiology, Stanford University, 450 Quarry Rd, Suite 5659, Palo Alto, CA 94304, USA
| | - Sonia Partap
- Department of Neurology and Neurological Sciences (Child Neurology Division), Stanford University, 750 Welch Road, Suite 317, Palo Alto, CA 94304, USA
| | - Laurence Katznelson
- Departments of Neurosurgery and Medicine (Endocrinology Division), Stanford University, 875 Blake Wilbur Drive, Stanford, CA 94305, USA
| | - Karen J Parker
- Department of Psychiatry and Behavioral Sciences, Stanford University, 1201 Welch Road, MSLS P-104, Stanford, CA 94305, USA; Department of Comparative Medicine, Stanford University, 300 Pasteur Drive, Stanford, CA 94305, USA.
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6
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Takata T, Hamada S, Mae Y, Iyama T, Ogihara R, Seno M, Nakamura K, Takata M, Sugihara T, Isomoto H. Uromodulin Regulates Murine Aquaporin-2 Activity via Thick Ascending Limb-Collecting Duct Cross-Talk during Water Deprivation. Int J Mol Sci 2022; 23:ijms23169410. [PMID: 36012675 PMCID: PMC9408883 DOI: 10.3390/ijms23169410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/14/2022] [Accepted: 08/16/2022] [Indexed: 12/03/2022] Open
Abstract
Uromodulin, a urinary protein synthesized and secreted from the thick ascending limb (TAL) of the loop of Henle, is associated with hypertension through the activation of sodium reabsorption in the TAL. Uromodulin is a potential target for hypertension treatment via natriuresis. However, its biological function in epithelial cells of the distal nephron segment, particularly the collecting duct, remains unknown. Herein, we examined the regulation of uromodulin production during water deprivation in vivo as well as the effect of uromodulin on the activity of the water channel aquaporin−2 (AQP2) in vitro and in vivo using transgenic mice. Water deprivation upregulated uromodulin production; immunofluorescence experiments revealed uromodulin adhesion on the apical surface of the collecting duct. Furthermore, the activation of AQP2 was attenuated in mice lacking uromodulin. Uromodulin enhanced the phosphorylation and apical trafficking of AQP2 in mouse collecting duct cells treated with the vasopressin analog dDAVP. The uromodulin-induced apical trafficking of AQP2 was attenuated via endocytosis inhibitor treatment, suggesting that uromodulin activates AQP2 through the suppression of endocytosis. This study provides novel insights into the cross−talk between TAL and the collecting duct, and indicates that the modulation of uromodulin is a promising approach for diuresis and hypertension treatment.
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Affiliation(s)
- Tomoaki Takata
- Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
- Correspondence: ; Tel.: +81-859-38-6527
| | - Shintaro Hamada
- Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Yukari Mae
- Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Takuji Iyama
- Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Ryohei Ogihara
- Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Misako Seno
- Advanced Medicine & Translational Research Center, Organization for Research Initiative and Promotion, Tottori University, Yonago 683-8504, Japan
| | - Kazuomi Nakamura
- Advanced Medicine, Innovation and Clinical Research Center, Tottori University Hospital, Yonago 683-8504, Japan
| | - Miki Takata
- Division of Respiratory Medicine and Rheumatology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Takaaki Sugihara
- Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Hajime Isomoto
- Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
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7
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Lin B, Ma YY, Wang JW. Nano-Technological Approaches for Targeting Kidney Diseases With Focus on Diabetic Nephropathy: Recent Progress, and Future Perspectives. Front Bioeng Biotechnol 2022; 10:870049. [PMID: 35646840 PMCID: PMC9136139 DOI: 10.3389/fbioe.2022.870049] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 04/18/2022] [Indexed: 12/13/2022] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of end-stage renal disease worldwide. With the rising prevalence of diabetes, the occurrence of DN is likely to hit pandemic proportions. The current treatment strategies employed for DN focus on the management of blood pressure, glycemia, and cholesterol while neglecting DN’s molecular progression mechanism. For many theranostic uses, nano-technological techniques have evolved in biomedical studies. Several nanotechnologically based theranostics have been devised that can be tagged with targeting moieties for both drug administration and/or imaging systems and are being studied to identify various clinical conditions. The molecular mechanisms involved in DN are discussed in this review to assist in understanding its onset and progression pattern. We have also discussed emerging strategies for establishing a nanomedicine-based platform for DN-targeted drug delivery to increase drug’s efficacy and safety, as well as their reported applications.
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Affiliation(s)
- Bo Lin
- Urology & Nephrology Center, Department of Nephrology, Zhejiang Provincial People’s Hospital (Affiliated People’s Hospital, Hangzhou Medical College), Hangzhou, China
| | - Ying-Yu Ma
- Key Laboratory of Gastroenterology of Zhejiang Province, Zhejiang Provincial People’s Hospital (Affiliated People’s Hospital, Hangzhou Medical College), Hangzhou, China
- Clinical Research Institute, Zhejiang Provincial People’s Hospital (Affiliated People’s Hospital, Hangzhou Medical College), Hangzhou, China
- *Correspondence: Ying-Yu Ma, ; Jun-Wei Wang,
| | - Jun-Wei Wang
- Emergency Department, Tiantai People’s Hospital of Zhejiang Province (Tiantai Branch of Zhejiang People’s Hospital), Taizhou, China
- *Correspondence: Ying-Yu Ma, ; Jun-Wei Wang,
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8
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Merlin JPJ, Li X. Role of Nanotechnology and Their Perspectives in the Treatment of Kidney Diseases. Front Genet 2022; 12:817974. [PMID: 35069707 PMCID: PMC8766413 DOI: 10.3389/fgene.2021.817974] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 12/06/2021] [Indexed: 12/12/2022] Open
Abstract
Nanoparticles (NPs) are differing in particle size, charge, shape, and compatibility of targeting ligands, which are linked to improved pharmacologic characteristics, targetability, and bioavailability. Researchers are now tasked with developing a solution for enhanced renal treatment that is free of side effects and delivers the medicine to the active spot. A growing number of nano-based medication delivery devices are being used to treat renal disorders. Kidney disease management and treatment are currently causing a substantial global burden. Renal problems are multistep processes involving the accumulation of a wide range of molecular and genetic alterations that have been related to a variety of kidney diseases. Renal filtration is a key channel for drug elimination in the kidney, as well as a burgeoning topic of nanomedicine. Although the use of nanotechnology in the treatment of renal illnesses is still in its early phases, it offers a lot of potentials. In this review, we summarized the properties of the kidney and characteristics of drug delivery systems, which affect a drug’s ability should focus on the kidney and highlight the possibilities, problems, and opportunities.
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Affiliation(s)
- J P Jose Merlin
- Department of Internal Medicine, Mayo Clinic, Rochester, MN, United States
| | - Xiaogang Li
- Department of Internal Medicine, Mayo Clinic, Rochester, MN, United States.,Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States
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9
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Yuen KCJ, Sharf V, Smith E, Kim M, Yuen ASM, MacDonald PR. Sodium and water perturbations in patients who had an acute stroke: clinical relevance and management strategies for the neurologist. Stroke Vasc Neurol 2021; 7:258-266. [PMID: 34969834 PMCID: PMC9240457 DOI: 10.1136/svn-2021-001230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 11/26/2021] [Indexed: 12/17/2022] Open
Abstract
Sodium and water perturbations, manifesting as hyponatraemia and hypernatraemia, are common in patients who had an acute stroke, and are associated with worse outcomes and increased mortality. Other non-stroke-related causes of sodium and water perturbations in these patients include underlying comorbidities and concomitant medications. Additionally, hospitalised patients who had an acute stroke may receive excessive intravenous hypotonic solutions, have poor fluid intake due to impaired neurocognition and consciousness, may develop sepsis or are administered drugs (eg, mannitol); factors that can further alter serum sodium levels. Sodium and water perturbations can also be exacerbated by the development of endocrine consequences after an acute stroke, including secondary adrenal insufficiency, syndrome of inappropriate antidiuretic hormone secretion and diabetes insipidus. Recently, COVID-19 infection has been reported to increase the risk of development of sodium and water perturbations that may further worsen the outcomes of patients who had an acute stroke. Because there are currently no accepted consensus guidelines on the management of sodium and water perturbations in patients who had an acute stroke, we conducted a systematic review of the literature published in English and in peer-reviewed journals between January 2000 and December 2020, according to PRISMA guidelines, to assess on the current knowledge and clinical practices of this condition. In this review, we discuss the signs and symptoms of hyponatraemia and hypernatraemia, the pathogenesis of hyponatraemia and hypernatraemia, their clinical relevance, and we provide our recommendations for effective treatment strategies for the neurologist in the management of sodium and water perturbations in commonly encountered aetiologies of patients who had an acute stroke.
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Affiliation(s)
- Kevin C J Yuen
- Departments of Neuroendocrinology and Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona, USA .,University of Arizona College of Medicine and Creighton School of Medicine, Phoenix, Arizona, USA
| | - Valerie Sharf
- University of Arizona College of Medicine and Creighton School of Medicine, Phoenix, Arizona, USA.,Department of Neurology, Barrow Neurological Institute, Phoenix, Arizona, USA
| | | | - Minhwan Kim
- Creighton University School of Medicine, Phoenix, Arizona, USA
| | | | - Paul R MacDonald
- University of Arizona College of Medicine and Creighton School of Medicine, Phoenix, Arizona, USA.,Department of Neurology, Barrow Neurological Institute, Phoenix, Arizona, USA
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10
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Bous J, Orcel H, Floquet N, Leyrat C, Lai-Kee-Him J, Gaibelet G, Ancelin A, Saint-Paul J, Trapani S, Louet M, Sounier R, Déméné H, Granier S, Bron P, Mouillac B. Cryo-electron microscopy structure of the antidiuretic hormone arginine-vasopressin V2 receptor signaling complex. SCIENCE ADVANCES 2021; 7:7/21/eabg5628. [PMID: 34020960 PMCID: PMC8139594 DOI: 10.1126/sciadv.abg5628] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 04/01/2021] [Indexed: 05/08/2023]
Abstract
The antidiuretic hormone arginine-vasopressin (AVP) forms a signaling complex with the V2 receptor (V2R) and the Gs protein, promoting kidney water reabsorption. Molecular mechanisms underlying activation of this critical G protein-coupled receptor (GPCR) signaling system are still unknown. To fill this gap of knowledge, we report here the cryo-electron microscopy structure of the AVP-V2R-Gs complex. Single-particle analysis revealed the presence of three different states. The two best maps were combined with computational and nuclear magnetic resonance spectroscopy constraints to reconstruct two structures of the ternary complex. These structures differ in AVP and Gs binding modes. They reveal an original receptor-Gs interface in which the Gαs subunit penetrates deep into the active V2R. The structures help to explain how V2R R137H or R137L/C variants can lead to two severe genetic diseases. Our study provides important structural insights into the function of this clinically relevant GPCR signaling complex.
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Affiliation(s)
- Julien Bous
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France
- Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France
| | - Hélène Orcel
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France
| | - Nicolas Floquet
- Institut des Biomolécules Max Mousseron, Université de Montpellier, CNRS, ENSCM, 34093 Montpellier cedex 5, France
| | - Cédric Leyrat
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France
| | - Joséphine Lai-Kee-Him
- Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France
| | - Gérald Gaibelet
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France
| | - Aurélie Ancelin
- Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France
| | - Julie Saint-Paul
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France
| | - Stefano Trapani
- Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France
| | - Maxime Louet
- Institut des Biomolécules Max Mousseron, Université de Montpellier, CNRS, ENSCM, 34093 Montpellier cedex 5, France
| | - Rémy Sounier
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France
| | - Hélène Déméné
- Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France
| | - Sébastien Granier
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France.
| | - Patrick Bron
- Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France.
| | - Bernard Mouillac
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier cedex 5, France.
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11
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Gomes DA, de Almeida Beltrão RL, de Oliveira Junior FM, da Silva Junior JC, de Arruda EPC, Lira EC, da Rocha MJA. Vasopressin and copeptin release during sepsis and septic shock. Peptides 2021; 136:170437. [PMID: 33181268 DOI: 10.1016/j.peptides.2020.170437] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 10/23/2020] [Accepted: 10/26/2020] [Indexed: 12/22/2022]
Abstract
Sepsis is defined as a potentially fatal organ dysfunction caused by a dysregulated host response to infection. Despite tremendous progress in the medical sciences, sepsis remains one of the leading causes of morbidity and mortality worldwide. The host response to sepsis and septic shock involves changes in the immune, autonomic, and neuroendocrine systems. Regarding neuroendocrine changes, studies show an increase in plasma vasopressin (AVP) concentrations followed by a decline, which may be correlated with septic shock. AVP is a peptide hormone derived from a larger precursor (preprohormone), along with two peptides, neurophysin II and copeptin. AVP is synthesized in the hypothalamus, stored and released from the neurohypophysis into the bloodstream by a wide range of stimuli. The measurement of AVP has limitations due to its plasma instability and short half-life. Copeptin is a more stable peptide than AVP, and its immunoassay is feasible. The blood concentrations of copeptin mirror those of AVP in many physiological states; paradoxically, during sepsis-related organ dysfunction, an uncoupling between copeptin and AVP blood levels appears to happen. In this review, we focus on clinical and experimental studies that analyzed AVP and copeptin blood concentrations over time in sepsis. The findings suggest that AVP and copeptin behave similarly in the early stages of sepsis; however, we did not find a proportional decrease in copeptin concentrations as seen with AVP during septic shock. Copeptin levels were higher in nonsurvivors than in survivors, suggesting that copeptin may work as a marker of severity or sepsis-related organ dysfunction.
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Affiliation(s)
- Dayane Aparecida Gomes
- Department of Physiology and Pharmacology, Bioscience Center, Federal University of Pernambuco, Brazil.
| | | | | | | | | | - Eduardo Carvalho Lira
- Department of Physiology and Pharmacology, Bioscience Center, Federal University of Pernambuco, Brazil
| | - Maria José Alves da Rocha
- Department of Basic and Oral Biology, School of Dentistry of Ribeirao Preto, University of Sao Paulo, Brazil
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12
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Sparapani S, Millet-Boureima C, Oliver J, Mu K, Hadavi P, Kalostian T, Ali N, Avelar CM, Bardies M, Barrow B, Benedikt M, Biancardi G, Bindra R, Bui L, Chihab Z, Cossitt A, Costa J, Daigneault T, Dault J, Davidson I, Dias J, Dufour E, El-Khoury S, Farhangdoost N, Forget A, Fox A, Gebrael M, Gentile MC, Geraci O, Gnanapragasam A, Gomah E, Haber E, Hamel C, Iyanker T, Kalantzis C, Kamali S, Kassardjian E, Kontos HK, Le TBU, LoScerbo D, Low YF, Mac Rae D, Maurer F, Mazhar S, Nguyen A, Nguyen-Duong K, Osborne-Laroche C, Park HW, Parolin E, Paul-Cole K, Peer LS, Philippon M, Plaisir CA, Porras Marroquin J, Prasad S, Ramsarun R, Razzaq S, Rhainds S, Robin D, Scartozzi R, Singh D, Fard SS, Soroko M, Soroori Motlagh N, Stern K, Toro L, Toure MW, Tran-Huynh S, Trépanier-Chicoine S, Waddingham C, Weekes AJ, Wisniewski A, Gamberi C. The Biology of Vasopressin. Biomedicines 2021; 9:89. [PMID: 33477721 PMCID: PMC7832310 DOI: 10.3390/biomedicines9010089] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/29/2020] [Accepted: 01/06/2021] [Indexed: 02/07/2023] Open
Abstract
Vasopressins are evolutionarily conserved peptide hormones. Mammalian vasopressin functions systemically as an antidiuretic and regulator of blood and cardiac flow essential for adapting to terrestrial environments. Moreover, vasopressin acts centrally as a neurohormone involved in social and parental behavior and stress response. Vasopressin synthesis in several cell types, storage in intracellular vesicles, and release in response to physiological stimuli are highly regulated and mediated by three distinct G protein coupled receptors. Other receptors may bind or cross-bind vasopressin. Vasopressin is regulated spatially and temporally through transcriptional and post-transcriptional mechanisms, sex, tissue, and cell-specific receptor expression. Anomalies of vasopressin signaling have been observed in polycystic kidney disease, chronic heart failure, and neuropsychiatric conditions. Growing knowledge of the central biological roles of vasopressin has enabled pharmacological advances to treat these conditions by targeting defective systemic or central pathways utilizing specific agonists and antagonists.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Chiara Gamberi
- Biology Department, Concordia University, Montreal, QC H4B 1R6, Canada; (S.S.); (C.M.-B.); (J.O.); (K.M.); (P.H.); (T.K.); (N.A.); (C.M.A.); (M.B.); (B.B.); (M.B.); (G.B.); (R.B.); (L.B.); (Z.C.); (A.C.); (J.C.); (T.D.); (J.D.); (I.D.); (J.D.); (E.D.); (S.E.-K.); (N.F.); (A.F.); (A.F.); (M.G.); (M.C.G.); (O.G.); (A.G.); (E.G.); (E.H.); (C.H.); (T.I.); (C.K.); (S.K.); (E.K.); (H.K.K.); (T.B.U.L.); (D.L.); (Y.F.L.); (D.M.R.); (F.M.); (S.M.); (A.N.); (K.N.-D.); (C.O.-L.); (H.W.P.); (E.P.); (K.P.-C.); (L.S.P.); (M.P.); (C.-A.P.); (J.P.M.); (S.P.); (R.R.); (S.R.); (S.R.); (D.R.); (R.S.); (D.S.); (S.S.F.); (M.S.); (N.S.M.); (K.S.); (L.T.); (M.W.T.); (S.T.-H.); (S.T.-C.); (C.W.); (A.J.W.); (A.W.)
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13
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Characterization of five novel vasopressin V2 receptor mutants causing nephrogenic diabetes insipidus reveals a role of tolvaptan for M272R-V2R mutation. Sci Rep 2020; 10:16383. [PMID: 33009446 PMCID: PMC7532466 DOI: 10.1038/s41598-020-73089-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/01/2020] [Indexed: 12/20/2022] Open
Abstract
Nephrogenic diabetes insipidus (NDI) is a rare tubulopathy characterized by urinary concentration defect due to renal resistance to vasopressin. Loss-of-function mutations of vasopressin V2 receptor (V2R) gene (AVPR2) is the most common cause of the disease. We have identified five novel mutations L86P, R113Q, C192S, M272R, and W323_I324insR from NDI-affected patients. Functional characterization of these mutants revealed that R113Q and C192S were normally localized at the basolateral membrane of polarized Madin-Darby Canine Kidney (MDCK) cells and presented proper glycosylation maturation. On the other side, L86P, M272R, and W323_I324insR mutants were retained in endoplasmic reticulum and exhibited immature glycosylation and considerably reduced stability. All five mutants were resistant to administration of vasopressin analogues as evaluated by defective response in cAMP release. In order to rescue the function of the mutated V2R, we tested VX-809, sildenafil citrate, ibuprofen and tolvaptan in MDCK cells. Among these, tolvaptan was effective in rescuing the function of M272R mutation, by both allowing proper glycosylation maturation, membrane sorting and response to dDAVP. These results show an important proof of concept for the use of tolvaptan in patients affected by M272R mutation of V2R causing NDI.
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Gasthuys E, Dossche L, Michelet R, Nørgaard JP, Devreese M, Croubels S, Vermeulen A, Van Bocxlaer J, Walle JV. Pediatric Pharmacology of Desmopressin in Children with Enuresis: A Comprehensive Review. Paediatr Drugs 2020; 22:369-383. [PMID: 32507959 DOI: 10.1007/s40272-020-00401-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Desmopressin is a synthetic analogue of the natural antidiuretic hormone arginine vasopressin. Over the years, it has been clinically used to manage nocturnal polyuria in children with enuresis. Various pharmaceutical formulations of desmopressin have been commercialized for this indication-nasal spray, nasal drops, oral tablet and oral lyophilizate. Despite the fact that desmopressin is a frequently prescribed drug in children, its use and posology is based on limited pediatric data. This review provides an overview of the current pediatric pharmacological data related to the different desmopressin formulations, including their pharmacokinetics, pharmacodynamics and adverse events. Regarding the pharmacokinetics, a profound food effect on the oral bioavailability was demonstrated as well as different plasma concentration-time profiles (double absorption peak) of the desmopressin lyophilizate between adults and children. Literature about maturational differences in distribution, metabolism and excretion of desmopressin is rather limited. Regarding the pharmacodynamics, formulation/dose/food effect and predictors of response were evaluated. The lyophilizate is the preferred formulation, but the claimed bioequivalence in adults (200 µg tablet and 120 µg lyophilizate), could not be readily extrapolated to children. Prescribing the standard flat-dose regimen to the entire pediatric population might be insufficient to attain response to desmopressin treatment, whereby dosing schemes based on age and weight were proposed. Moreover, response to desmopressin is variable, whereby complete-, partial- and non-responders are reported. Different reasons were enumerated that might explain the difference in response rate to desmopressin observed: different pathophysiological mechanisms, bladder capacity and other predictive factors (i.e. breast feeding, familial history, compliance, sex, etc.). Also, the relapse rate of desmopressin treatment was high, rendering it necessary to use a pragmatic approach for the treatment of enuresis, whereby careful consideration of the position of desmopressin within this treatment is required. Regarding the safety of the different desmopressin formulations, the use of desmopressin was generally considered safe, but additional measures should be taken to prevent severe hyponatremia. To conclude the review, to date, major knowledge gaps in pediatric pharmacological aspects of the different desmopressin formulations still remain. Additional information should be collected about the clinical relevance of the double absorption peak, the food effect, the bioequivalence/therapeutic equivalence, the pediatric adapted dosing regimens, the study endpoints and the difference between performing studies at daytime or at nighttime. To fill in these gaps, additional well designed pharmacokinetic and pharmacodynamic studies in children should be performed.
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Affiliation(s)
- Elke Gasthuys
- Department of Pediatric Nephrology, Faculty of Medicine and Health Sciences, Ghent University Hospital, C. Heymanslaan 10, 9000, Ghent, Belgium.
- Health, Innovation and Research Institute, Faculty of Medicine and Health Sciences, Ghent University Hospital, C. Heymanslaan 10, 9000, Ghent, Belgium.
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Freie Universitaet Berlin, Kelchstr. 31, 12169, Berlin, Germany.
- Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium.
| | - Lien Dossche
- Department of Pediatric Nephrology, Faculty of Medicine and Health Sciences, Ghent University Hospital, C. Heymanslaan 10, 9000, Ghent, Belgium
| | - Robin Michelet
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Freie Universitaet Berlin, Kelchstr. 31, 12169, Berlin, Germany
| | - Jens Peter Nørgaard
- Department of Pediatric Nephrology, Faculty of Medicine and Health Sciences, Ghent University Hospital, C. Heymanslaan 10, 9000, Ghent, Belgium
| | - Mathias Devreese
- Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Siska Croubels
- Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - An Vermeulen
- Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Jan Van Bocxlaer
- Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Johan Vande Walle
- Department of Pediatric Nephrology, Faculty of Medicine and Health Sciences, Ghent University Hospital, C. Heymanslaan 10, 9000, Ghent, Belgium
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15
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Patel S, Volpe AB, Awwad S, Schätzlein AG, Haider S, Liu B, Uchegbu IF. A Self-Assembling Lipidic Peptide and Selective Partial V2 Receptor Agonist Inhibits Urine Production. Sci Rep 2020; 10:7269. [PMID: 32350300 PMCID: PMC7190706 DOI: 10.1038/s41598-020-64070-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 02/21/2020] [Indexed: 11/09/2022] Open
Abstract
Lipidised analgesic peptide prodrugs self-assemble into peptide nanofibers; with the nanofiber morphology protecting the peptide from plasma degradation and improving therapeutic efficacy. Extending this learning, we hypothesised that a self-assembling lipidized peptide arginine vasopressin (AVP) receptor agonist, that had not been designed as a prodrug, could prove pharmacologically active and control urine production. The only approved AVP receptor agonist, desmopressin is indicated for the treatment of central diabetes insipidus (DI), bedwetting, haemophilia A and von Willebrand disease. Desmopressin is well tolerated by most patients, however adverse effects, such as hyponatraemia and water intoxication necessitate a strict fluid intake, thus motivating the search for alternative DI treatments. Selective V2 receptor agonism is required for anti-DI activity and we hypothesised that our new lipidized peptide (METx) would lead to selective AVP receptor agonism. METx was synthesised and characterised and then tested for activity against the V2, V1a and OT uterine receptors and not tested against the V1b receptor as METx was not expected to cross the blood brain barrier. METx was also tested in vivo in a healthy rat model. METx forms nanofibers and is a partial V2 receptor agonist (determined by measuring MDCK cell line cAMP accumulation), producing 57% of AVP's maximal activity (EC50 = 2.7 nM) and is not a V1a agonist up to a concentration of 1 μM (determined by measuring A7r5 cell line D-myo-inositol-1-phosphate accumulation). METx is a weak OT receptor antagonist, reducing the frequency of OT induced contractions (EC50 = 350 nM) and increasing the OT EC50 from 0.081 nM to 21 nM at a concentration of 600 nM. METx (41 nM) had no effect on spontaneous uterine contractions and METx (100 nM) had no effect on OT induced uterine contractions. Simulated binding studies show that binding avidity to the receptors follows the trend: V2 > OT > V1a. On intravenous injection, a nanoparticle formulation of METx reduced urine production in a healthy rat model in a dose responsive manner, with 40 mg kg-1 METx resulting in no urine production over 4 hours. The lipidized self-assembling peptide - METx - is a selective competitive V2 receptor agonist and an anti-diuretic.
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Affiliation(s)
- Sunish Patel
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | | | - Sahar Awwad
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Andreas G Schätzlein
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK.,Nanomerics Ltd. 30-34 New Bridge Street, London, EC4V 6BJ, UK
| | - Shozeb Haider
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Boqian Liu
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Ijeoma F Uchegbu
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK. .,Nanomerics Ltd. 30-34 New Bridge Street, London, EC4V 6BJ, UK.
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16
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Protein misfolding in endoplasmic reticulum stress with applications to renal diseases. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020. [PMID: 31928726 DOI: 10.1016/bs.apcsb.2019.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Protein misfolding may be the result of a variety of different processes that disrupt the ability of a protein to form a thermodynamically stable tertiary structure that allows it to perform its proper function. In this chapter, we explore the nature of a protein's form that allows it to have a stable tertiary structure, and examine specific mutation that are known to occur in the coding regions of DNA that disrupt a protein's ability to be folded into a thermodynamically stable tertiary structure. We examine the consequences of these protein misfoldings in terms of the endoplasmic reticulum stress response and resulting unfolded protein response. These conditions are specifically related to renal diseases. Further, we explore novel therapeutics, pharmacological chaperones, that are being developed to alleviate the disease burden associated with protein misfolding caused by mutations. These interventions aim to stabilize protein folding intermediates and allow proper folding to occur as well as prevent protein aggregation and the resulting pathophysiological consequences.
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17
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Parker KJ, Oztan O, Libove RA, Mohsin N, Karhson DS, Sumiyoshi RD, Summers JE, Hinman KE, Motonaga KS, Phillips JM, Carson DS, Fung LK, Garner JP, Hardan AY. A randomized placebo-controlled pilot trial shows that intranasal vasopressin improves social deficits in children with autism. Sci Transl Med 2019; 11:scitranslmed.aau7356. [PMID: 31043522 DOI: 10.1126/scitranslmed.aau7356] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/30/2018] [Accepted: 01/26/2019] [Indexed: 01/26/2023]
Abstract
The social impairments of autism spectrum disorder (ASD) have a major impact on quality of life, yet there are no medications that effectively treat these core social behavior deficits. Preclinical research suggests that arginine vasopressin (AVP), a neuropeptide involved in promoting mammalian social behaviors, may be a possible treatment for ASD. Using a double-blind, randomized, placebo-controlled, parallel study design, we tested the efficacy and tolerability of a 4-week intranasal AVP daily treatment in 30 children with ASD. AVP-treated participants aged 6 to 9.5 years received the maximum daily target dose of 24 International Units (IU); participants aged 9.6 to 12.9 years received the maximum daily target dose of 32 IU. Intranasal AVP treatment compared to placebo enhanced social abilities as assessed by change from baseline in this phase 2 trial's primary outcome measure, the Social Responsiveness Scale, 2nd Edition total score (SRS-2 T score; F 1,20 = 9.853; P = 0.0052; ηp 2 = 33.0%; Cohen's d = 1.40). AVP treatment also diminished anxiety symptoms and some repetitive behaviors. Most of these findings were more pronounced when we accounted for pretreatment AVP concentrations in blood. AVP was well tolerated with minimal side effects. No AVP-treated participants dropped out of the trial, and there were no differences in the rate of adverse events reported between treatment conditions. Last, no changes from baseline were observed in vital signs, electrocardiogram tracings, height and body weight, or clinical chemistry measurements after 4 weeks of AVP treatment. These preliminary findings suggest that AVP has potential for treating social impairments in children with ASD.
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Affiliation(s)
- Karen J Parker
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA.
| | - Ozge Oztan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Robin A Libove
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Noreen Mohsin
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Debra S Karhson
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Raena D Sumiyoshi
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Jacqueline E Summers
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Kyle E Hinman
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Kara S Motonaga
- Department of Pediatrics, Stanford University, Stanford, CA 94305, USA
| | - Jennifer M Phillips
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Dean S Carson
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Lawrence K Fung
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Joseph P Garner
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA.,Department of Comparative Medicine, Stanford University, Stanford, CA 94305, USA
| | - Antonio Y Hardan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
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Er Shen Wan extract alleviates polyuria and regulates AQP 2 and AVPR 2 in a rat model of spleen-kidney Yang deficiency-induced diarrhea. Biomed Pharmacother 2018; 110:302-311. [PMID: 30522016 DOI: 10.1016/j.biopha.2018.11.147] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 02/08/2023] Open
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Er Shen Wan (ESW), has been empirically used for treating spleen-kidney Yang deficiency (SKYD) syndrome in Traditional Chinese medicine (TCM) for centuries and shows a variety of activities. The medicinal formula is a mixture of two component herbs, Psoraleae Fructus (PF, Bu-Gu-Zhi in Chinese) and Myristicae Semen (MS, Rou-Dou-Kou in Chinese). The current study was designed to evaluate ESWP antidiuretic treatment of polyuria and to explore potential mechanisms of renal water metabolism in the rat model of SKYD-induced diarrhea. MATERIALS AND METHODS An animal model of 'SKYD-induced diarrhea syndrome' has been established to evaluate the therapeutic effect and action mechanism according to the clinical syndrome and symptoms. The optimal dose (3.5 g/kg) of ESWP was given to rats by gavage for two weeks. Urinary volumes after 24 h were recorded. After the end of the trial, macroscopic morphological and histological examination of the kidney were conducted. Serum levels of Arginine vasopressin (AVP) and aldosterone (ALD) were also measured. Additionally, quantitative real-time RT-PCR (RT-qPCR) and immunohistochemistry (IHC) analyses were performed to clarify the regulation of aquaporin 2 (AQP 2) and arginine vasopressin type 2 receptor (AVPR 2) in the kidney at the gene and tissue expression levels respectively. RESULTS After the administration of ESWP, urinary output volume after 24 h was found to be significantly decreased in rats. Elevated plasma levels of AVP and ALD were detected. Histological kidney damage appeared to be impeded, and histological disease scores were reduced. In addition, the expression levels of AQP 2 and AVPR 2 were significantly increased. CONCLUSION This study suggests that ESWP may elicit significant effects on the treatment of polyuria. Potential mechanisms at least partially involve hormone regulation, and alleviating renal pathological damage. Simultaneously, ESWP may alter renal water absorption by increasing AQP 2 and AVPR 2 expression levels. Thus, the in vivo experimental evidence indicates that ESWP has a therapeutic effect on the SKYD syndrome, which is consistent with its traditional usage.
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19
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Milano S, Carmosino M, Gerbino A, Svelto M, Procino G. Hereditary Nephrogenic Diabetes Insipidus: Pathophysiology and Possible Treatment. An Update. Int J Mol Sci 2017; 18:ijms18112385. [PMID: 29125546 PMCID: PMC5713354 DOI: 10.3390/ijms18112385] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 11/03/2017] [Accepted: 11/07/2017] [Indexed: 12/17/2022] Open
Abstract
Under physiological conditions, excessive loss of water through the urine is prevented by the release of the antidiuretic hormone arginine-vasopressin (AVP) from the posterior pituitary. In the kidney, AVP elicits a number of cellular responses, which converge on increasing the osmotic reabsorption of water in the collecting duct. One of the key events triggered by the binding of AVP to its type-2 receptor (AVPR2) is the exocytosis of the water channel aquaporin 2 (AQP2) at the apical membrane the principal cells of the collecting duct. Mutations of either AVPR2 or AQP2 result in a genetic disease known as nephrogenic diabetes insipidus, which is characterized by the lack of responsiveness of the collecting duct to the antidiuretic action of AVP. The affected subject, being incapable of concentrating the urine, presents marked polyuria and compensatory polydipsia and is constantly at risk of severe dehydration. The molecular bases of the disease are fully uncovered, as well as the genetic or clinical tests for a prompt diagnosis of the disease in newborns. A real cure for nephrogenic diabetes insipidus (NDI) is still missing, and the main symptoms of the disease are handled with s continuous supply of water, a restrictive diet, and nonspecific drugs. Unfortunately, the current therapeutic options are limited and only partially beneficial. Further investigation in vitro or using the available animal models of the disease, combined with clinical trials, will eventually lead to the identification of one or more targeted strategies that will improve or replace the current conventional therapy and grant NDI patients a better quality of life. Here we provide an updated overview of the genetic defects causing NDI, the most recent strategies under investigation for rescuing the activity of mutated AVPR2 or AQP2, or for bypassing defective AVPR2 signaling and restoring AQP2 plasma membrane expression.
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Affiliation(s)
- Serena Milano
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70126 Bari, Italy.
| | - Monica Carmosino
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy.
| | - Andrea Gerbino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70126 Bari, Italy.
| | - Maria Svelto
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70126 Bari, Italy.
| | - Giuseppe Procino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70126 Bari, Italy.
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20
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Shimizu K, Sano M, Kita A, Sawai N, Iizuka-Kogo A, Kogo H, Aoki T, Takata K, Matsuzaki T. Phosphorylation and dephosphorylation of aquaporin-2 at serine 269 and its subcellular distribution during vasopressin-induced exocytosis and subsequent endocytosis in the rat kidney . ACTA ACUST UNITED AC 2017. [DOI: 10.1679/aohc.77.25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | - Nobuhiko Sawai
- Present address: Department of Molecular Medicine and Anatomy, Nippon Medical School,
| | | | | | - Takeo Aoki
- Present address: School of Radiological Technology, Gunma Prefectural College of Health Sciences,
| | - Kuniaki Takata
- Present address: Gunma Prefectural College of Health Sciences,
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Katkova LE, Baturina GS, Solenov EI, Ivanova LN. Regulation of V2 receptor by vasopressin is different in Brattleboro rats compared with Wistar. DOKL BIOCHEM BIOPHYS 2015; 463:247-50. [PMID: 26335823 DOI: 10.1134/s1607672915040158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Indexed: 11/22/2022]
Abstract
This paper presents the new priority data on the effect of genetically determined deficiency of endogenous vasopressin on the functioning of V2 receptor in the plasma membrane of the principal cells of the collection ducts of Brattleboro rats. It was found that 2-day desmopressin administration results in the activation of V2 receptor gene expression in Brattleboro rat, whereas in Wistar rats the content of mRNA did not change. In addition, short-term exposure of the collection ducts of the kidneys to the hormone led to V2 receptor internalization from the plasma membrane in Wistar rats, but had no effect on the protein content in Brattleboro rats.
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Affiliation(s)
- L E Katkova
- Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, pr. Akademika Lavrent'eva 10, Novosibirsk, 630090, Russia,
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22
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Ayoub MA, Landomiel F, Gallay N, Jégot G, Poupon A, Crépieux P, Reiter E. Assessing Gonadotropin Receptor Function by Resonance Energy Transfer-Based Assays. Front Endocrinol (Lausanne) 2015; 6:130. [PMID: 26379624 PMCID: PMC4550792 DOI: 10.3389/fendo.2015.00130] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 08/10/2015] [Indexed: 11/13/2022] Open
Abstract
Gonadotropin receptors belong to the super family of G protein-coupled receptors and mediate the physiological effects of follicle-stimulating hormone (FSHR) and luteinizing hormone (LHR). Their central role in the control of reproductive function has made them the focus of intensive studies. Upon binding to their cognate hormone, they trigger complex signaling and trafficking mechanisms that are tightly regulated in concentration, time, and space. Classical cellular assays often fail to capture all these dynamics. Here, we describe the use of various bioluminescence and fluorescence resonance energy transfer (BRET and FRET) assays to investigate the activation and regulation of FSHR and LHR in real-time, in living cells (i.e., transiently expressed in human embryonic kidney 293 cells). Indeed, the dynamics of hormone-mediated heterotrimeric G protein activation, cyclic adenosine-monophosphate (cAMP) production, calcium release, β-arrestin 2 recruitment, and receptor internalization/recycling was assessed. Kinetics and dose-response analyses confirmed the expected pharmacological and signaling properties of hFSHR and hLHR but revealed interesting characteristics when considering the two major pathways (cAMP and β-arrestin 2) of the two receptors assessed by BRET. Indeed, the EC50 values were in picomolar range for cAMP production while nanomolar range was observed for β-arrestin 2 recruitment as well as receptor internalization. Interestingly, the predicted receptor occupancy indicates that the maximal G protein activation and cAMP response occur at <10% of receptor occupancy whereas >90% of activated receptors is required to achieve full β-arrestin 2 recruitment and subsequent receptor internalization. The rapid receptor internalization was also followed by a recycling phase. Collectively, our data reveal that β-arrestin-mediated desensitization, internalization, and the subsequent fast recycling of receptors at the plasma membrane may provide a mechanistic ground to the "spare receptor" paradigm. More generally, the novel tools described here will undoubtedly provide the scientific community investigating gonadotropin receptors with powerful means to decipher their pharmacology and signaling with the prospect of pathophysiological and drug discovery applications.
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Affiliation(s)
- Mohammed Akli Ayoub
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France
- CNRS, UMR7247, Nouzilly, France
- Université François Rabelais, Tours, France
- L’Institut français du cheval et de l’équitation (IFCE), Nouzilly, France
- LE STUDIUM Loire Valley Institute for Advanced Studies, Orléans, France
- *Correspondence: Mohammed Akli Ayoub, Institut National de la Recherche Agronomique (INRA) UMR85, CNRS-Université François Rabelais UMR7247, Physiologie de la Reproduction et des Comportements (PRC) - Nouzilly 37380, France,
| | - Flavie Landomiel
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France
- CNRS, UMR7247, Nouzilly, France
- Université François Rabelais, Tours, France
- L’Institut français du cheval et de l’équitation (IFCE), Nouzilly, France
| | - Nathalie Gallay
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France
- CNRS, UMR7247, Nouzilly, France
- Université François Rabelais, Tours, France
- L’Institut français du cheval et de l’équitation (IFCE), Nouzilly, France
| | - Gwenhael Jégot
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France
- CNRS, UMR7247, Nouzilly, France
- Université François Rabelais, Tours, France
- L’Institut français du cheval et de l’équitation (IFCE), Nouzilly, France
| | - Anne Poupon
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France
- CNRS, UMR7247, Nouzilly, France
- Université François Rabelais, Tours, France
- L’Institut français du cheval et de l’équitation (IFCE), Nouzilly, France
| | - Pascale Crépieux
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France
- CNRS, UMR7247, Nouzilly, France
- Université François Rabelais, Tours, France
- L’Institut français du cheval et de l’équitation (IFCE), Nouzilly, France
| | - Eric Reiter
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France
- CNRS, UMR7247, Nouzilly, France
- Université François Rabelais, Tours, France
- L’Institut français du cheval et de l’équitation (IFCE), Nouzilly, France
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Abstract
PURPOSE OF REVIEW Aquaporin-2 (AQP2) water channels in principal cells of the kidney collecting duct are essential for urine concentration. Due to application of modern technologies, progress in our understanding of AQP2 has accelerated in recent years. In this article, we highlight some of the new insights into AQP2 function that have developed recently, with particular focus on the cell biological aspects of AQP2 regulation. RECENT FINDINGS AQP2 is subjected to a number of regulated modifications, including phosphorylation and ubiquitination, which are important for AQP2 function, cellular localization and degradation. AQP2 is likely internalized via clathrin and non-clathrin-mediated endocytosis. Regulation of AQP2 endocytosis, in addition to exocytosis, is a vital mechanism in determining overall AQP2 membrane abundance. AQP2 is associated with regulated membrane microdomains. Studies using membrane cholesterol depleting reagents, for example statins, have supported the role of membrane rafts in regulation of AQP2 trafficking. Noncanonical roles for AQP2, for example in epithelial cell migration, are emerging. SUMMARY AQP2 function and thus urine concentration is dependent on a variety of cell signalling mechanisms, posttranslational modification and interplay between AQP2 and its lipid environment. This complexity of regulation allows fine-tuning of AQP2 function and thus body water homeostasis.
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Kortenoeven MLA, Sinke AP, Hadrup N, Trimpert C, Wetzels JFM, Fenton RA, Deen PMT. Demeclocycline attenuates hyponatremia by reducing aquaporin-2 expression in the renal inner medulla. Am J Physiol Renal Physiol 2013; 305:F1705-18. [PMID: 24154696 DOI: 10.1152/ajprenal.00723.2012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Binding of vasopressin to its type 2 receptor in renal collecting ducts induces cAMP signaling, transcription and translocation of aquaporin (AQP)2 water channels to the plasma membrane, and water reabsorption from the prourine. Demeclocycline is currently used to treat hyponatremia in patients with the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Demeclocycline's mechanism of action, which is poorly understood, is studied here. In mouse cortical collecting duct (mpkCCD) cells, which exhibit deamino-8-D-arginine vasopressin (dDAVP)-dependent expression of endogenous AQP2, demeclocycline decreased AQP2 abundance and gene transcription but not its protein stability. Demeclocycline did not affect vasopressin type 2 receptor localization but decreased dDAVP-induced cAMP generation and the abundance of adenylate cyclase 3 and 5/6. The addition of exogenous cAMP partially corrected the demeclocycline effect. As in patients, demeclocycline increased urine volume, decreased urine osmolality, and reverted hyponatremia in an SIADH rat model. AQP2 and adenylate cyclase 5/6 abundances were reduced in the inner medulla but increased in the cortex and outer medulla, in the absence of any sign of toxicity. In conclusion, our in vitro and in vivo data indicate that demeclocycline mainly attenuates hyponatremia in SIADH by reducing adenylate cyclase 5/6 expression and, consequently, cAMP generation, AQP2 gene transcription, and AQP2 abundance in the renal inner medulla, coinciding with a reduced vasopressin escape response in other collecting duct segments.
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Affiliation(s)
- Marleen L A Kortenoeven
- no. 286, Dept. of Physiology, Radboud Univ. Medical Centre, PO Box 9101, Nijmegen 6500 HB, The Netherlands.
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Kortenoeven MLA, Pedersen NB, Miller RL, Rojek A, Fenton RA. Genetic ablation of aquaporin-2 in the mouse connecting tubules results in defective renal water handling. J Physiol 2013; 591:2205-19. [PMID: 23359673 DOI: 10.1113/jphysiol.2012.250852] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Body water balance is regulated via the water channel aquaporin-2 (AQP2), which is expressed in the renal connecting tubule (CNT) and collecting duct (CD). The relative roles of AQP2 in the CNT and CD are not fully understood. To study the role of AQP2 in the CNT we generated a mouse model with CNT-specific AQP2 deletion (AQP2-CNT-knockout (KO)). Confocal laser scanning microscopy and immunogold electron microscopy demonstrated an absence of AQP2 in the CNT of AQP2-CNT-KO mice. Twenty-four hour urine output was significantly increased (KO: 3.0 ± 0.3 ml (20 g body weight (BW))(-1); wild-type (WT): 1.9 ± 0.3 ml (20 g BW)(-1)) and urine osmolality decreased (KO: 1179 ± 107 mosmol kg(-1); WT: 1790 ± 146 mosmol kg(-1)) in AQP2-CNT-KO mice compared with controls. After 24 h water restriction, urine osmolality was still significantly lower in AQP2-CNT-KO mice (KO: 2087 ± 169 mosmol kg(-1); WT: 2678 ± 144 mosmol kg(-1)). A significant difference in urine osmolality between groups before desmopressin (dDAVP) (KO: 873 ± 129 mosmol kg(-1); WT: 1387 ± 163 mosmol kg(-1)) was not apparent 2 h after injection, with urine osmolality increased significantly in both groups (KO: 2944 ± 41 mosmol kg(-1); WT: 3133 ± 66 mosmol kg(-1)). Cortical kidney fractions from AQP2-CNT-KO mice had significantly reduced AQP2, with no compensatory changes in sodium potassium chloride cotransporter (NKCC2), AQP3 or AQP4. Lithium chloride treatment increased urine volume and decreased osmolality in both WT and AQP2-CNT-KO mice. After 8 days of treatment, the AQP2-CNT-KO mice still had a significantly higher urine volume and lower urine osmolality, suggesting that the CNT does not play a significant role in the pathology of lithium-induced nephrogenic diabetes insipidus. Our studies indicate that the CNT plays a role in regulating body water balance under basal conditions, but not for maximal concentration of the urine during antidiuresis.
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26
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Bouley R, Nunes P, Andriopoulos B, McLaughlin M, Webber MJ, Lin HY, Babitt JL, Gardella TJ, Ausiello DA, Brown D. Heterologous downregulation of vasopressin type 2 receptor is induced by transferrin. Am J Physiol Renal Physiol 2012; 304:F553-64. [PMID: 23235478 DOI: 10.1152/ajprenal.00438.2011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Vasopressin (VP) binds to the vasopressin type 2 receptor (V2R) to trigger physiological effects including body fluid homeostasis and blood pressure regulation. Signaling is terminated by receptor downregulation involving clathrin-mediated endocytosis and V2R degradation. We report here that both native and epitope-tagged V2R are internalized from the plasma membrane of LLC-PK1 kidney epithelial cells in the presence of another ligand, transferrin (Tf). The presence of iron-saturated Tf (holo-Tf; 4 h) reduced V2R binding sites at the cell surface by up to 33% while iron-free (apo-Tf) had no effect. However, no change in green fluorescent protein-tagged V2R distribution was observed in the presence of bovine serum albumin, atrial natriuretic peptide, or ANG II. Conversely, holo-Tf did not induce the internalization of another G protein-coupled receptor, the parathyroid hormone receptor. In contrast to the effect of VP, Tf did not increase intracellular cAMP or modify aquaporin-2 distribution in these cells, although addition of VP and Tf together augmented VP-induced V2R internalization. Tf receptor coimmunoprecipitated with V2R, suggesting that they interact closely, which may explain the additive effect of VP and Tf on V2R endocytosis. Furthermore, Tf-induced V2R internalization was abolished in cells expressing a dominant negative dynamin (K44A) mutant, indicating the involvement of clathrin-coated pits. We conclude that Tf can induce heterologous downregulation of the V2R and this might desensitize VP target cells without activating downstream V2R signaling events. It also provides new insights into urine-concentrating defects observed in rat models of hemochromatosis.
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Affiliation(s)
- Richard Bouley
- 1Nephrology Division, MGH Center for Systems Biology, Program in Membrane Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
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27
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Congenital nephrogenic diabetes insipidus: the current state of affairs. Pediatr Nephrol 2012; 27:2183-204. [PMID: 22427315 DOI: 10.1007/s00467-012-2118-8] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 01/14/2012] [Accepted: 01/17/2012] [Indexed: 01/02/2023]
Abstract
The anti-diuretic hormone arginine vasopressin (AVP) is released from the pituitary upon hypovolemia or hypernatremia, and regulates water reabsorption in the renal collecting duct principal cells. Binding of AVP to the arginine vasopressin receptor type 2 (AVPR2) in the basolateral membrane leads to translocation of aquaporin 2 (AQP2) water channels to the apical membrane of the collecting duct principal cells, inducing water permeability of the membrane. This results in water reabsorption from the pro-urine into the medullary interstitium following an osmotic gradient. Congenital nephrogenic diabetes insipidus (NDI) is a disorder associated with mutations in either the AVPR2 or AQP2 gene, causing the inability of patients to concentrate their pro-urine, which leads to a high risk of dehydration. This review focuses on the current knowledge regarding the cell biological aspects of congenital X-linked, autosomal-recessive and autosomal-dominant NDI while specifically addressing the latest developments in the field. Based on deepened mechanistic understanding, new therapeutic strategies are currently being explored, which we also discuss here.
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28
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Jung HJ, Lim JS, Choi HJ, Lee MS, Kim JH, Kim SY, Kim S, Kim E, Kwon TH. Vasopressin V2R-targeting peptide carrier mediates siRNA delivery into collecting duct cells. PLoS One 2012; 7:e40010. [PMID: 22761946 PMCID: PMC3386242 DOI: 10.1371/journal.pone.0040010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Accepted: 05/30/2012] [Indexed: 01/05/2023] Open
Abstract
Internalization of receptor proteins after interacting with specific ligands has been proposed to facilitate siRNA delivery into the target cells via receptor-mediated siRNA transduction. In this study, we demonstrated a novel method of vasopressin V2 receptor (V2R)-mediated siRNA delivery against AQP2 in primary cultured inner medullary collecting duct (IMCD) cells of rat kidney. We synthesized the dDAVP conjugated with nine D-arginines (dDAVP-9r) as a peptide carrier for siRNA delivery. The structure of synthetic peptide carrier showed two regions (i.e., ligand domain to V2R (dDAVP) and siRNA carrying domain (nine D-arginine)) bisected with a spacer of four glycines. The results revealed that 1) synthesized dDAVP-9r peptides formed a stable polyplex with siRNA; 2) siRNA/dDAVP-9r polyplex could bind to the V2R of IMCD cells and induced AQP2 phosphorylation (Ser 256); 3) siRNA/dDAVP-9r polyplex was stable in response to the wide range of different osmolalities, pH levels, or to the RNases; 4) fluorescein-labeled siRNA was delivered into V2R-expressing MDCK and LLC-PK1 cells by siRNA/dDAVP-9r polyplex, but not into the V2R-negative Cos-7 cells; and 5) AQP2-siRNA/dDAVP-9r polyplex effectively delivered siRNA into the IMCD cells, resulting in the significant decrease of protein abundance of AQP2, but not AQP4. Therefore, for the first time to our knowledge, we demonstrated that V2R-mediated siRNA delivery could be exploited to deliver specific siRNA to regulate abnormal expression of target proteins in V2R-expressing kidney cells. The methods could be potentially used in vivo to regulate abnormal expression of proteins associated with disease conditions in the V2R-expressing kidney cells.
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Affiliation(s)
- Hyun Jun Jung
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
| | - Jung-Suk Lim
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
| | - Hyo-Jung Choi
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
| | - Mi Suk Lee
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
| | - Jong-Ho Kim
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
- Department of Pharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul, Korea
| | - Sang-Yeob Kim
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
| | - Soyoun Kim
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
| | - Eunjung Kim
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
| | - Tae-Hwan Kwon
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu Korea
- * E-mail:
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29
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Kortenoeven MLA, Trimpert C, van den Brand M, Li Y, Wetzels JFM, Deen PMT. In mpkCCD cells, long-term regulation of aquaporin-2 by vasopressin occurs independent of protein kinase A and CREB but may involve Epac. Am J Physiol Renal Physiol 2012; 302:F1395-401. [PMID: 22419689 DOI: 10.1152/ajprenal.00376.2011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Urine concentration involves the hormone vasopressin (AVP), which stimulates cAMP production in renal principal cells, resulting in translocation and transcription of aquaporin-2 (AQP2) water channels, greatly increasing the water permeability, leading to a concentrated urine. As cAMP levels decrease shortly after AVP addition, whereas AQP2 levels still increase and are maintained for days, we investigated in the present study the mechanism responsible for the AQP2 increase after long-term 1-desamino-8-d-arginine vasopressin (dDAVP) application using mouse collecting duct (mpkCCD) cells. While 30 min of dDAVP incubation strongly increased cAMP, cAMP was lower with 1 day and was even further reduced with 4 days of dDAVP, although still significantly higher than in control cells. One day of dDAVP incubation increased AQP2 promoter-dependent transcription, which was blocked by the protein kinase A (PKA) inhibitor H89. Moreover, phosphorylation of the cAMP-responsive element binding protein (CREB) and CRE-dependent transcription was observed after short-term dDAVP stimulation. With 4 days of dDAVP, AQP2 transcription remained elevated, but this was not blocked by H89, and CRE-dependent transcription and CREB phosphorylation were not increased. Exchange factor directly activated by cAMP (Epac) 1 and 2 were found to be endogenously expressed in mpkCCD cells. Application of dDAVP increased the expression of Epac1, while Epac2 was reduced. Incubation with a specific Epac activator after dDAVP pretreatment increased both AQP2 abundance and transcription compared with cells left unstimulated the last day. In conclusion, the PKA-CRE pathway is involved in the initial rise in AQP2 levels after dDAVP stimulation but not in the long-term effect of dDAVP. Instead, long-term regulation of AQP2 may involve the activation of Epac.
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Affiliation(s)
- Marleen L A Kortenoeven
- Department of Physiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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30
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Saigusa T, Reichert R, Guare J, Siroky BJ, Gooz M, Steele S, Fenton RA, Bell PD, Kolb RJ. Collecting duct cells that lack normal cilia have mislocalized vasopressin-2 receptors. Am J Physiol Renal Physiol 2011; 302:F801-8. [PMID: 22205228 DOI: 10.1152/ajprenal.00253.2011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Polycystic kidney disease (PKD) is a ciliopathy characterized by renal cysts and hypertension. These changes are presumably due to altered fluid and electrolyte transport in the collecting duct (CD). This is the site where vasopressin (AVP) stimulates vasopressin-2 receptor (V2R)-mediated aquaporin-2 (AQP2) insertion into the apical membrane. Since cysts frequently occur in the CD, we studied V2R and AQP2 trafficking and function in CD cell lines with stunted and normal cilia [cilia (-), cilia (+)] derived from the orpk mouse (hypomorph of the Tg737/Ift88 gene). Interestingly, only cilia (-) cells grown on culture dishes formed domes after apical AVP treatment. This observation led to our hypothesis that V2R mislocalizes to the apical membrane in the absence of a full-length cilium. Immunofluorescence indicated that AQP2 localizes to cilia and in a subapical compartment in cilia (+) cells, but AQP2 levels were elevated in both apical and basolateral membranes in cilia (-) cells after apical AVP treatment. Western blot analysis revealed V2R and glycosylated AQP2 in biotinylated apical membranes of cilia (-) but not in cilia (+) cells. In addition, apical V2R was functional upon apical desmopressin (DDAVP) treatment by demonstrating increased cAMP, water transport, and benzamil-sensitive equivalent short-circuit current (I(sc)) in cilia (-) cells but not in cilia (+) cells. Moreover, pretreatment with a PKA inhibitor abolished DDAVP stimulation of I(sc) in cilia (-) cells. Thus we propose that structural or functional loss of cilia leads to abnormal trafficking of AQP2/V2R leading to enhanced salt and water absorption. Whether such apical localization contributes to enhanced fluid retention and hypertension in PKD remains to be determined.
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Affiliation(s)
- Takamitsu Saigusa
- Dept. of Medicine, Division of Nephrology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
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31
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Chen S, Webber MJ, Vilardaga JP, Khatri A, Brown D, Ausiello DA, Lin HY, Bouley R. Visualizing microtubule-dependent vasopressin type 2 receptor trafficking using a new high-affinity fluorescent vasopressin ligand. Endocrinology 2011; 152:3893-904. [PMID: 21828182 PMCID: PMC3176653 DOI: 10.1210/en.2011-1049] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The vasopressin receptor type 2 (V2R) is the major target of vasopressin (VP) in renal epithelial cells. Although it is known that VP induces V2R internalization, accumulation in the perinuclear area, and degradation, the V2R intracellular trafficking pathways remain elusive. We visualized this process by developing a new fluorescent VP analog tagged by tetramethylrhodamine (TMR)-[Lys-(PEG)(2)-Suc-TMR(8)]VP or (VP(TMR)). This ligand is fully functional as revealed by its high binding affinity toward V2R [(K(d)) =157 ± 52 nM] and ability to increase intracellular cAMP 32-fold. VP(TMR) induced V2R internalization in LLC-PK1 cells expressing either a FLAG-tagged receptor (FLAG-V2R) or V2R C-terminally tagged with green fluorescent protein (GFP) (V2R-GFP). After internalization, VP(TMR) and V2R-GFP colocalized in the perinuclear area, suggesting that the hormone and receptor traffic along the same pathway. VP(TMR) and V2R colocalized initially with the early endosome markers EEA1 and Rab5, and later with the recycling and late endosome markers Rab11 and Rab25. Epifluorescence microscopy of LLC-PK1 cells expressing GFP-tagged microtubules (MT) showed that VP(TMR)-containing vesicles travel along the MT network, and even remain attached to MT during the metaphase and anaphase of mitosis. Colchicine, a MT-depolymerizing agent, abolished perinuclear accumulation of VP(TMR), and Western blot analysis showed that VP-induced V2R-GFP degradation is markedly retarded, but not abolished, by colchicine (10 μM). We conclude that the new VP(TMR) ligand is suitable for dissecting V2R and VP internalization and trafficking in cells, and that V2R trafficking and down-regulation is an MT-dependent mechanism.
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Affiliation(s)
- Sylvia Chen
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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32
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Nejsum LN, Christensen TM, Robben JH, Milligan G, Deen PMT, Bichet DG, Levin K. Novel mutation in the AVPR2 gene in a Danish male with nephrogenic diabetes insipidus caused by ER retention and subsequent lysosomal degradation of the mutant receptor. NDT Plus 2011; 4:158-163. [PMID: 21629670 PMCID: PMC3103721 DOI: 10.1093/ndtplus/sfr010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Accepted: 01/24/2011] [Indexed: 12/28/2022] Open
Abstract
Mutations in the arginine vasopressin receptor 2 (AVPR2) gene can cause X-linked nephrogenic diabetes insipidus (NDI) characterized by the production of large amounts of urine and an inability to concentrate urine in response to the antidiuretic hormone vasopressin. We have identified a novel mutation in the AVPR2 gene (L170P) located in the fourth transmembrane domain in a Danish NDI male. Analysis of the mutant receptor in Madin-Darby Canine Kidney cell culture revealed that AVPR2-L170P was retained in the endoplasmic reticulum, and the expression was dramatically downregulated compared to wild-type AVPR2. Inhibition of the lysosome resulted in increased intracellular accumulation of AVPR2-L170P, indicating that AVPR2-L170P is downregulated via the lysosome. Inhibition of the proteasome resulted in plasma membrane localization of AVPR2-L170P, although the overall levels of AVPR2-L170P were unchanged.
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Affiliation(s)
- Lene N. Nejsum
- Department of Biology, Stanford University, Stanford, CA, USA
- Present address: Department of Molecular Biology, Aarhus University, C. F. Moellers Allé 3, Aarhus, Denmark
| | | | - Joris H. Robben
- Department of Physiology, Nijmegen Centre for Molecular Life Sciences, Radboud University, Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Graeme Milligan
- Molecular Pharmacology Group, Institute of Neuroscience and Psychology College of Medical, Veterinary and Life Sciences University of Glasgow, Glasgow, UK
| | - Peter M. T. Deen
- Department of Physiology, Nijmegen Centre for Molecular Life Sciences, Radboud University, Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Daniel G. Bichet
- Department of Medicine and Physiology, Université de Montreal, Montreal, Canada
| | - Klaus Levin
- Department of Endocrinology, Bispebjerg Hospital, Copenhagen, Denmark
- Department of Endocrinology, Odense University Hospital, Svendborg, Denmark
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Karavashkina TA, Kutina AV, Shakhmatova EI, Natochin YV. Mechanism of 1-deamino-arginine vasotocin induced natriuresis in rats. Gen Comp Endocrinol 2011; 170:460-7. [PMID: 21050856 DOI: 10.1016/j.ygcen.2010.10.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Revised: 10/15/2010] [Accepted: 10/25/2010] [Indexed: 10/18/2022]
Abstract
1-Deamino-arginine vasotocin (1dAVT) induced diuresis and a considerable increase in urinary sodium excretion in female Wistar rats. Sodium fractional excretion rose up to 19.3 ± 1.1%. An increase in urine flow rate after 1dAVT (0.5 nmol/kg body-weight [bw]) injection was accompanied by a significant rise of the solute-free water reabsorption. The 1dAVT-induced natriuresis was as high as natriuresis produced by injection of a maximal dose of furosemide (10mg/kg bw). V(1)-receptor antagonists (ОРС-21268, [β-mercapto-β,β-cyclopentamethylenepropionyl(1),O-Me-Tyr(2),Arg(8)]-vasopressin) blocked the increase in urinary sodium excretion after the 1dAVT injection. The 1dAVT-induced natriuresis was strongly correlated with an increase in the urinary cGMP and prostaglandin E(2) excretion. The natriuretic effect of 1dAVT did not depend on the formation of nitric oxide (NO) or atrial natriuretic peptide of which concentration in the rat blood serum remained stable. The above results indicate that the 1dAVT has unique effects on rat kidney compared to all other known diuretics - it induces extremely high natriuresis and stimulates solute-free water reabsorption. Mechanism of the natriuretic effect of 1dAVT includes decrease in tubular sodium reabsorption due to activation of V(1)-like receptors and formation of cGMP and PGЕ(2).
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Affiliation(s)
- Tatjana A Karavashkina
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Thorez Av 44, St Petersburg 194223, Russia
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Nossent AY, Robben JH, Deen PMT, Vos HL, Rosendaal FR, Doggen CJM, Hansen JL, Sheikh SP, Bertina RM, Eikenboom JCJ. Functional variation in the arginine vasopressin 2 receptor as a modifier of human plasma von Willebrand factor levels. J Thromb Haemost 2010; 8:1547-54. [PMID: 20403097 DOI: 10.1111/j.1538-7836.2010.03884.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
SUMMARY OBJECTIVES Stimulation of arginine vasopressin 2 receptor (V2R) with arginine vasopressin (AVP) results in a rise in von Willebrand factor (VWF) and factor VIII plasma levels. We hypothesized that gain-of-function variations in the V2R gene (AVPR2) would lead to higher plasma levels of VWF and FVIII. METHODS AND RESULTS We genotyped the control populations of two population-based studies for four AVPR2 variations: a-245c, G12E, L309L, and S331S. Rare alleles of a-245c, G12E, and S331S, which were in linkage disequilibrium, were associated with higher VWF propeptide, VWF and FVIII levels. The functionality of the G12E variant was studied in stably transfected MDCKII cells, expressing constructs of either 12G-V2R or 12E-V2R. Both V2R variants were fully glycosylated and expressed on the basolateral membrane. The binding affinity of V2R for AVP was increased three-fold in 12E-V2R-green fluorescent protein (GFP) cells, which is in accordance with increased levels of VWF propeptide associated with the 12E variant. The dissociation constant (K(D)) was 4.5 nm [95% confidence interval (CI) 3.6-5.4] for 12E-V2R-GFP and 16.5 nm (95% CI 10.1-22.9) for 12G-V2R-GFP. AVP-induced cAMP generation was enhanced in 12E-V2R-GFP cells. CONCLUSIONS The 12E-V2R variant has increased binding affinity for AVP, resulting in increased signal transduction, and is associated with increased levels of VWF propeptide, VWF, and FVIII.
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Affiliation(s)
- A Y Nossent
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Thrombosis and Hemostasis, Leiden University Medical Center, RC Leiden, the Netherlands
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Levtchenko EN, Monnens LAH. Nephrogenic syndrome of inappropriate antidiuresis. Nephrol Dial Transplant 2010; 25:2839-43. [DOI: 10.1093/ndt/gfq324] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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36
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Nishioka R, Takeda T, Kakigi A, Okada T, Takebayashi S, Taguchi D, Nishimura M, Hyodo M. Expression of aquaporins and vasopressin type 2 receptor in the stria vascularis of the cochlea. Hear Res 2010; 260:11-9. [DOI: 10.1016/j.heares.2009.09.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 09/21/2009] [Accepted: 09/23/2009] [Indexed: 10/20/2022]
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37
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Faerch M, Christensen JH, Rittig S, Johansson JO, Gregersen N, de Zegher F, Corydon TJ. Diverse vasopressin V2 receptor functionality underlying partial congenital nephrogenic diabetes insipidus. Am J Physiol Renal Physiol 2009; 297:F1518-25. [PMID: 19812297 DOI: 10.1152/ajprenal.00331.2009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
X-linked congenital nephrogenic diabetes insipidus (CNDI) is characterized by a defective renal response to the antidiuretic hormone (AVP) due to variations in the arginine vasopressin receptor 2 (AVPR2) gene. In a unique group of patients, the renal insensitivity to the effects of AVP is incomplete resulting in a partial phenotype. To investigate the molecular defects, two previously published variations in the AVPR2 gene, known to cause a partial CNDI phenotype, were expressed in transiently transfected human embryonic kidney cells. One variation (p.Arg104Cys) is located in the first extracellular loop and the other variation (p.Ser329Arg) is located in the intracellular COOH terminal of the receptor protein. Western blotting showed almost equal amounts of WT-V2R and Arg104Cys-V2R protein at steady state, whereas the level of Ser329Arg-V2R protein was lower. Confocal microscopy established that WT-V2R and Arg104Cys-V2R are localized on the cellular surface while the Ser329Arg-V2R primarily accumulates within the endoplasmic reticulum resulting in reduced surface expression. Ligand binding analysis demonstrated that the B(max) for cells expressing Arg104Cys-V2R and Ser329Arg-V2R were 14.8- and 2.5-fold lower than B(max) for WT-V2R, respectively. AVP affinity (1/K(d)) for WT-V2R and the Ser329Arg-V2R was similar while 1/K(d) for Arg104Cys-V2R was increased. cAMP assay revealed that cells expressing p.Arg104Cys-V2R or p.Ser329Arg-V2R produced 1.7- and 6.8-fold lower amounts of cAMP compared with WT-V2R, respectively. In conclusion, ligand binding and signal transduction capability are dependent on localization of the amino acid variation. Striking divergences at the level of receptor functionality may thus underlie similar clinical phenotypes in CNDI.
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Affiliation(s)
- Mia Faerch
- Department of Pediatrics, Aarhus University Hospital, Skejby, Denmark.
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38
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Localization of the succinate receptor in the distal nephron and its signaling in polarized MDCK cells. Kidney Int 2009; 76:1258-67. [PMID: 19776718 DOI: 10.1038/ki.2009.360] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
When the succinate receptor (SUCNR1) is activated in the afferent arterioles of the glomerulus it increases renin release and induces hypertension. To study its location in other nephron segments and its role in kidney function, we performed immunohistochemical analysis and found that SUCNR1 is located in the luminal membrane of macula densa cells of the juxtaglomerular apparatus in close proximity to renin-producing granular cells, the cortical thick ascending limb, and cortical and inner medullary collecting duct cells. In order to study its signaling, SUCNR1 was stably expressed in Madin-Darby Canine Kidney (MDCK) cells, where it localized to the apical membrane. Activation of the cells by succinate caused Gq and Gi-mediated intracellular calcium mobilization, transient phosphorylation of extracellular regulated kinase (ERK)1/2 and the release of arachidonic acid along with prostaglandins E2 and I2. Signaling was desensitized without receptor internalization but rapidly resensitized upon succinate removal. Immunohistochemical evidence of phosphorylated ERK1/2 was found in cortical collecting duct cells of wild type but not SUCNR1 knockout streptozotocin-induced diabetic mice, indicating in vivo relevance. Since urinary succinate concentrations in health and disease are in the activation range of the SUCNR1, this receptor can sense succinate in the luminal fluid. Our study suggests that changes in the luminal succinate concentration may regulate several aspects of renal function.
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Jean-Alphonse F, Perkovska S, Frantz MC, Durroux T, Méjean C, Morin D, Loison S, Bonnet D, Hibert M, Mouillac B, Mendre C. Biased agonist pharmacochaperones of the AVP V2 receptor may treat congenital nephrogenic diabetes insipidus. J Am Soc Nephrol 2009; 20:2190-203. [PMID: 19729439 DOI: 10.1681/asn.2008121289] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
X-linked congenital nephrogenic diabetes insipidus (cNDI) results from inactivating mutations of the human arginine vasopressin (AVP) V2 receptor (hV(2)R). Most of these mutations lead to intracellular retention of the hV(2)R, preventing its interaction with AVP and thereby limiting water reabsorption and concentration of urine. Because the majority of cNDI-hV(2)Rs exhibit protein misfolding, molecular chaperones hold promise as therapeutic agents; therefore, we sought to identify pharmacochaperones for hV(2)R that also acted as agonists. Here, we describe high-affinity nonpeptide compounds that promoted maturation and membrane rescue of L44P, A294P, and R337X cNDI mutants and restored a functional AVP-dependent cAMP signal. Contrary to pharmacochaperone antagonists, these compounds directly activated a cAMP signal upon binding to several cNDI mutants. In addition, these molecules displayed original functionally selective properties (biased agonism) toward the hV(2)R, being unable to recruit arrestin, trigger receptor internalization, or stimulate mitogen-activated protein kinases. These characteristics make these hV(2)R agonist pharmacochaperones promising therapeutic candidates for cNDI.
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Affiliation(s)
- Frédéric Jean-Alphonse
- CNRS UMR 5203, Institut de Génomique fonctionnelle, INSERM U661, and Université Montpellier I and II, Montpellier, France
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40
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Intracellular activation of vasopressin V2 receptor mutants in nephrogenic diabetes insipidus by nonpeptide agonists. Proc Natl Acad Sci U S A 2009; 106:12195-200. [PMID: 19587238 DOI: 10.1073/pnas.0900130106] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Binding of the peptide hormone vasopressin to its type-2 receptor (V2R) in kidney triggers a cAMP-mediated translocation of Aquaporin-2 water channels to the apical membrane, resulting in water reabsorption and thereby preventing dehydration. Mutations in the V2R gene lead to Nephrogenic Diabetes Insipidus (NDI), a disorder in which this process is disturbed, because the encoded, often intrinsically functional mutant V2 receptors are misfolded and retained in the endoplasmic reticulum (ER). Since plasma membrane expression is thought to be essential for V2R activation, cell permeable V2R antagonists have been used to induce maturation and rescue cell surface expression of V2R mutants, after which they need to be displaced by vasopressin for activation. Here, however, we show that 3 novel nonpeptide V2R agonists, but not vasopressin, activate NDI-causing V2R mutants at their intracellular location, without changing their maturation and at a sufficient level to induce the translocation of aquaporin-2 to the apical membrane. Moreover, in contrast to plasma membrane V2R, degradation of intracellular V2R mutants is not increased by their activation. Our data reveal that G protein-coupled receptors (GPCRs) normally active at the plasma membrane can be activated intracellularly and that intracellular activation does not induce their degradation; the data also indicate that nonpeptide agonists constitute highly promising therapeutics for diseases caused by misfolded GPCRs in general, and NDI in particular.
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Cliffe ST, Kramer JM, Hussain K, Robben JH, de Jong EK, de Brouwer AP, Nibbeling E, Kamsteeg EJ, Wong M, Prendiville J, James C, Padidela R, Becknell C, van Bokhoven H, Deen PMT, Hennekam RCM, Lindeman R, Schenck A, Roscioli T, Buckley MF. SLC29A3 gene is mutated in pigmented hypertrichosis with insulin-dependent diabetes mellitus syndrome and interacts with the insulin signaling pathway. Hum Mol Genet 2009; 18:2257-65. [PMID: 19336477 DOI: 10.1093/hmg/ddp161] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pigmented hypertrichotic dermatosis with insulin-dependent diabetes (PHID) syndrome is a recently described autosomal recessive disorder associated with predominantly antibody negative, insulin-dependent diabetes mellitus. In order to identify the genetic basis of PHID and study its relationship with glucose metabolism, we performed homozygosity mapping in five unrelated families followed by candidate gene sequencing. Five loss-of-function mutations were identified in the SLC29A3 gene which encodes a member of a highly conserved protein family that transports nucleosides, nucleobases and nucleoside analogue drugs, hENT3. We show that PHID is allelic with a related syndrome without diabetes mellitus, H syndrome. The interaction of SLC29A3 with insulin signaling pathways was then studied using an established model in Drosophila melanogaster. Ubiquitous knockdown of the Drosophila ortholog of hENT3, dENT1 is lethal under stringent conditions; whereas milder knockdown induced scutellar bristle phenotypes similar to those previously reported in the knockdown of the Drosophila ortholog of the Islet gene. A cellular growth assay showed a reduction of cell size/number which could be rescued or enhanced by manipulation of the Drosophila insulin receptor and its downstream signaling effectors, dPI3K and dAkt. In summary, inactivating mutations in SLC29A3 cause a syndromic form of insulin-dependent diabetes in humans and in Drosophila profoundly affect cell size/number through interactions with the insulin signaling pathway. These data suggest that further investigation of the role of SLC29A3 in glucose metabolism is a priority for diabetes research.
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Affiliation(s)
- Simon T Cliffe
- Department of Haematology and Genetics, South Eastern Area Laboratory Services, Sydney, NSW 2031, Australia
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Schmidt A, Wiesner B, Weißhart K, Schulz K, Furkert J, Lamprecht B, Rosenthal W, Schülein R. Use of Kaede Fusions to Visualize Recycling of G Protein-Coupled Receptors. Traffic 2008; 10:2-15. [DOI: 10.1111/j.1600-0854.2008.00843.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zalyapin EA, Bouley R, Hasler U, Vilardaga JP, Lin HY, Brown D, Ausiello DA. Effects of the renal medullary pH and ionic environment on vasopressin binding and signaling. Kidney Int 2008; 74:1557-67. [PMID: 18813286 DOI: 10.1038/ki.2008.412] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The kidney has a cortico-medullary interstitial gradient of decreasing pH and increasing concentrations of sodium chloride and urea, but the influence of these gradients on receptor signaling is largely unknown. Here, we measured G-protein coupled receptor function in LLC-PK1 cells acutely exposed to conditions mimicking different kidney regions. Signaling through the parathyroid hormone receptor, normally expressed in the cortex, was greatly reduced at an acidic pH similar to that of the inner medulla. Parathyroid hormone receptor, tagged with green fluorescent protein, showed no ligand-induced internalization. In contrast, under both acidic and hyperosmotic conditions, vasopressin increased intracellular cAMP, and upon binding to its type 2 receptor (V2R) was internalized and degraded. Dose-displacement binding assays with selective vasopressin/oxytocin receptor ligands under inner medullary conditions indicated a shift in the V2R pharmacological profile. Oxytocin did not bind to the V2R, as it does under normal conditions and the vasopressin type 1 receptor (V1R) had reduced affinity for vasopressin compared to the V2R in low pH and high osmolality. We suggest that the cortico-medullary gradient causes a receptor-specific selectivity in ligand binding that is of functional significance to the kidney. While the gradient is important for urinary concentration, it may also play a substantial role in fine-tuning of the vasopressin response through the V2R.
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Affiliation(s)
- Elena A Zalyapin
- Program in Membrane Biology and Nephrology Division, MGH Center for Systems Biology, Boston, Massachusetts 02114, USA
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Schwieger I, Lautz K, Krause E, Rosenthal W, Wiesner B, Hermosilla R. Derlin-1 and p97/valosin-containing protein mediate the endoplasmic reticulum-associated degradation of human V2 vasopressin receptors. Mol Pharmacol 2007; 73:697-708. [PMID: 18048502 DOI: 10.1124/mol.107.040931] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The endoplasmic reticulum-associated degradation (ERAD), the main quality control pathway of the cell, is crucial for the elimination of unfolded or misfolded proteins. Several diseases are associated with the retention of misfolded proteins in the early secretory pathway. Among them is X-linked nephrogenic diabetes insipidus, caused by mutations in the gene encoding the V2 vasopressin receptor (V2R). We studied the degradation pathways of three intracellularly retained V2R mutants with different misfolded domains in human embryonic kidney 293 cells. At steady state, the wild-type V2R and the complex-glycosylated mutant G201D were partially located in lysosomes, whereas core-glycosylated mutants L62P and V226E were excluded from this compartment. In pulse-chase experiments, proteasomal inhibition stabilized the nonglycosylated and core-glycosylated forms of all studied receptors. In addition, all mutants and the wild-type receptor were found to be polyubiquitinylated. Nonglycosylated and core-glycosylated receptor forms were located in cytosolic and membrane fractions, respectively, confirming the deglycosylation and retrotranslocation of ERAD substrates to the cytosol. Distinct Derlin-1-dependent and -independent ERAD pathways have been proposed for proteins with different misfolded domains (cytosolic, extracellular, and membrane) in yeast. Here, we show for the first time that V2R mutants with different misfolded domains are able to coprecipitate the ERAD components p97/valosin-containing protein, Derlin-1 and the 26S proteasome regulatory subunit 7. Our results demonstrate the presence of a Derlin-1-mediated ERAD pathway degrading wild-type and disease-causing V2R mutants with different misfolded domains in a mammalian system.
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Affiliation(s)
- Isabel Schwieger
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Campus Buch, Robert-Rössle Str. 10, 13125 Berlin, Germany
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Hervé JC, Derangeon M, Bahbouhi B, Mesnil M, Sarrouilhe D. The connexin turnover, an important modulating factor of the level of cell-to-cell junctional communication: comparison with other integral membrane proteins. J Membr Biol 2007; 217:21-33. [PMID: 17673963 DOI: 10.1007/s00232-007-9054-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Accepted: 06/04/2007] [Indexed: 12/25/2022]
Abstract
The constituent proteins of gap junctions, called "connexins" (Cxs) in chordates, are generally renewed several times a day, in approximately the same rate range as many other integral plasma membrane proteins and the proteins of other channels, other intercellular junctions or different membrane receptors. This permanent renewal turns on a fine-tuned balance among various processes, such as gene transcription, mRNA stability and processing, protein synthesis and oligomerization, posttranslational modifications, transport to the plasma membrane, anchoring to the cytoskeleton, connexon aggregation and docking, regulation of endocytosis and controlled degradations of the proteins. Subtle changes at one or some of these steps would represent an exquisite level of regulation that extends beyond the rapid channel opening and closure events associated with channel gating; membrane channels and receptors are constantly able to answer to physiological requirements to either up- or downregulate their activity. The Cx turnover rate thereby appears to be a key component in the regulation of any protein, particularly of gap junctional proteins. However, the physiological stimuli that control the assembly of Cxs into gap junctions and their degradation remain poorly understood.
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Affiliation(s)
- Jean-Claude Hervé
- Institut de Physiologie et Biologie Cellulaires, Faculté des Sciences Fondamentales et Appliquées, UMR CNRS 6187, Université de Poitiers, 40, avenue du R Pineau, 86022, Poitiers, France.
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46
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Yangthara B, Mills A, Chatsudthipong V, Tradtrantip L, Verkman AS. Small-molecule vasopressin-2 receptor antagonist identified by a g-protein coupled receptor "pathway" screen. Mol Pharmacol 2007; 72:86-94. [PMID: 17435162 DOI: 10.1124/mol.107.034496] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) such as the vasopressin-2 receptor (V(2)R) are an important class of drug targets. We developed an efficient screen for GPCR-induced cAMP elevation using as read-out cAMP activation of cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channels. Fischer rat thyroid cells expressing CFTR and a halide-sensing yellow fluorescent protein (H148Q/I152L) were transfected with V(2)R. Increased cell Cl(-) conductance after agonist-induced cAMP elevation was assayed using a plate reader from cell fluorescence after solution I(-) addition. The Z' factor for the assay was approximately 0.7 with the V(2)R agonist [deamino-Cys1, Val4, d-Arg8]-vasopressin (1 nM) as positive control. Primary screening of 50,000 small molecules yielded a novel, 5-aryl-4-benzoyl-3-hydroxy-1-(2-arylethyl)-2H-pyrrol-2-one class of V(2)R antagonists that are unrelated structurally to known V(2)R antagonists. The most potent compound, V(2)R(inh)-02, which was identified by screening 35 structural analogs, competitively inhibited V(2)R-induced cAMP elevation with K(i) value of approximately 70 nM and fully displaced radiolabeled vasopressin in binding experiments. V(2)R(inh)-02 did not inhibit forskolin or beta(2)-adrenergic receptor-induced cAMP production and was more than 50 times more potent for V(2)R than for V(1a)R. The favorable in vitro properties of the pyrrol-2-one antagonists suggests their potential usefulness in aquaretic applications. The CFTR-linked cAMP assay developed here is applicable for efficient, high-throughput identification of modulators of cAMP-coupled GPCRs.
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Affiliation(s)
- Buranee Yangthara
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California 94143-0521, USA
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47
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Robben JH, Sze M, Knoers NV, Eggert P, Deen P, Müller D. Relief of Nocturnal Enuresis by Desmopressin Is Kidney and Vasopressin Type 2 Receptor Independent. J Am Soc Nephrol 2007; 18:1534-9. [PMID: 17389737 DOI: 10.1681/asn.2006080907] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Primary nocturnal enuresis (PNE) is a common problem in childhood and adolescence. Although various treatments are highly effective, a common underlying hypothesis on the pathogenesis is lacking. The success of desmopressin, a synthetic analogue of the antidiuretic hormone vasopressin, has been attributed to increased renal water reabsorption that is mediated by activation of the renal vasopressin V2 receptor (V2R). However, this effect does not explain other symptoms of PNE, such as the failure to arouse upon bladder distension. This study identified a family in which one child displayed PNE and coexisting nephrogenic diabetes insipidus, as a result of a novel nonsense mutation in the V2R gene (C358X). Cell-biologic investigations revealed that V2R-C358X is retained in the endoplasmic reticulum and is unstable, which explains his nephrogenic diabetes insipidus. Consistently, extrarenal V2R-mediated responses were absent in the patient who was treated with desmopressin. Administration of desmopressin, however, changed his PNE into nocturia, because he now still voided unchanged high urinary volumes at night but woke up and went to the bathroom. Withdrawal of desmopressin was accompanied by bedwetting, whereas reintroduction again relieved the symptoms. Therefore, these data indicate that neither a functioning renal concentration system nor a functional V2R is needed for the therapeutic benefit of desmopressin in PNE. Rather, it suggests that another vasopressin receptor and other organ(s) is the target for desmopressin to relieve PNE.
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Affiliation(s)
- Joris H Robben
- Department of Physiology, Nijmegen Centre of Molecular Life Sciences, Nijmegen, Netherlands
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48
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Yi X, Bouley R, Lin HY, Bechoua S, Sun TX, Del Re E, Shioda T, Raychowdhury MK, Lu HAJ, Abou-Samra AB, Brown D, Ausiello DA. Alix (AIP1) is a vasopressin receptor (V2R)-interacting protein that increases lysosomal degradation of the V2R. Am J Physiol Renal Physiol 2007; 292:F1303-13. [PMID: 17287200 DOI: 10.1152/ajprenal.00441.2005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The vasopressin type 2 receptor (V2R) is a G protein-coupled receptor that plays a central role in renal water reabsorption. Termination of ligand (vasopressin) stimulation is an important physiological regulatory event, but few proteins that interact with the V2R during downregulation after vasopressin (VP) binding have been identified. Using yeast two-hybrid screening of a human kidney cDNA library, we show that a 100-kDa protein called ALG-2-interacting protein X (Alix) interacts with the last 29 amino acids of the V2R COOH terminus. This was confirmed by pull-down assays using a GST-V2R-COOH-tail fusion protein. Alix was immunolocalized in principal cells of the kidney, which also express the V2R. The function of the Alix-V2R interaction was studied by transfecting Alix into LLC-PK(1) epithelial cells expressing V2R-green fluorescent protein (GFP). Under basal conditions, V2R-GFP localized mainly at the plasma membrane. On VP treatment, V2R-GFP was internalized into perinuclear vesicles in the nontransfected cells. In contrast, V2R-GFP fluorescence was virtually undetectable 2 h after exposure to VP in cells that coexpressed Alix. Western blotting using an anti-GFP antibody showed marked degradation of the V2R after 2 h in the presence of VP and Alix, a time point at which little or no degradation was detected in the absence of Alix. In contrast, little or no degradation of the parathyroid hormone receptor was detectable in the presence or absence of Alix and/or the PTH ligand. The VP-induced disappearance of V2R-GFP was abolished by chloroquine, a lysosomal degradation inhibitor, but not by MG132, a proteosome inhibitor. These data suggest that Alix increases the rate of lysosomal degradation of V2R and may play an important regulatory role in the VP response by modulating V2R downregulation.
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Affiliation(s)
- Xianhua Yi
- Cellular Biophysics Laboratory, Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas, USA
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Izumi Y, Nakayama Y, Mori T, Miyazaki H, Inoue H, Kohda Y, Inoue T, Nonoguchi H, Tomita K. Downregulation of vasopressin V2 receptor promoter activity via V1a receptor pathway. Am J Physiol Renal Physiol 2007; 292:F1418-26. [PMID: 17213462 DOI: 10.1152/ajprenal.00358.2006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Vasopressin V(1a) and V(2) receptors (V(1a)R and V(2)R, respectively) distribute in the collecting duct of the kidney. Although the function of V(2)R mediating the antidiuretic effect of AVP has been investigated in detail, the role of V(1a)R in the collecting ducts has not been elucidated. In the present study, we have investigated the role of the V(1a)R pathway in V(2)R promoter activity. We cloned the 5'-flanking region of rat V(2)R (rV(2)R) and investigated rV(2)R promoter activity in the LLC-PK(1) cell line transfected to express rat V(1a)R (rV(1a)R) dominantly (LLC-PK(1)/rV(1a)R). AVP induced a transient increase, followed by a sustained decrease, of rV(2)R promoter activity in these cells. This AVP-induced decrease of rV(2)R promoter activity was inhibited by V(1a)R, but not V(2)R, antagonist. PMA mimicked this decrease of rV(2)R promoter activity. On the contrary, 8-(4-chlorophenylthio)-cAMP increased rV(2)R promoter activity. These PMA- and 8-(4-chlorophenylthio)-cAMP-induced effects were not observed on the deletion segment of the 5'-flanking region lacking CAAT and SP1 sites. In conclusion, 1) expression of the V(2)R is downregulated via the V(1a)R pathway in LLC-PK(1)/rV(1a)R cells, and 2) expression of the V(2)R is downregulated by the PMA-induced PKC pathway and upregulated by the cAMP-PKA pathway. These opposite effects of PKC and PKA appear to be regulated by the same promoter region of CAAT and SP1.
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Affiliation(s)
- Yuichiro Izumi
- Department of Nephrology, Graduate School of Medical Sciences, Kumamoto University, Kunamoto, Japan.
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Robben JH, Sze M, Knoers NVAM, Deen PMT. Functional rescue of vasopressin V2 receptor mutants in MDCK cells by pharmacochaperones: relevance to therapy of nephrogenic diabetes insipidus. Am J Physiol Renal Physiol 2006; 292:F253-60. [PMID: 16926443 DOI: 10.1152/ajprenal.00247.2006] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Intracellular retention of a functional vasopressin V2 receptor (V2R) is a major cause of congenital nephrogenic diabetes insipidus (NDI) and rescue of V2R mutants by nonpeptide antagonists may restore their basolateral membrane (BM) localization and function. However, the criteria for efficient functional rescue of G protein-coupled receptor (GPCR) mutants at clinically feasible antagonist concentrations are unknown. We found that the four nonpeptide antagonists SR49059, OPC31260, OPC41061, and SR121463B induced maturation and rescued the BM expression of eight of nine different V2R mutants, stably expressed in physiologically relevant polarized cells. The extent of maturation and rescued BM expression correlated with the antagonists' concentration and affinity for the V2R. Displacement of the antagonists by AVP and subsequent cAMP generation inversely correlated with the antagonists' affinities for the V2R but is partially influenced by antagonist-specific aspects. Despite limited increases in maturation and cell-surface expression of V2R mutants, the low-affinity SR49059 optimally induced functional rescue at high concentrations, due to its easy displacement by vasopressin. At clinically feasible antagonist concentrations, however, only the high-affinity antagonists OPC31260 and OPC41061 induced functional rescue, as at these concentrations the extent of BM expression became limited. In conclusion, functional rescue of mutant V2Rs at clinically feasible concentrations is most effective with high-affinity antagonists. As OPC31260 and OPC41061 are clinically safe, they are promising candidates to relieve NDI. Moreover, as numerous other diseases are caused by endoplasmic reticulum-retained GPCRs for which cell-permeable antagonists become available, our finding that high-affinity antagonists are superior is anticipated to be important for pharmacotherapy development of these diseases.
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Affiliation(s)
- J H Robben
- Department of Physiology, Nijmegen Centre for Molecular Life Sciences, The Netherlands
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