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Gupta NP, Singh C, Aggarwal A, Batra A, Sharma A, Sundar J. Newborn with Polyuria and Hydrocephalus. Neoreviews 2023; 24:e658-e664. [PMID: 37777618 DOI: 10.1542/neo.24-10-e658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/02/2023]
Affiliation(s)
- Naveen Parkash Gupta
- Department of Neonatology, Madhukar Rainbow Children's Hospital, New Delhi, India
| | - Chanchal Singh
- Department of Fetal Medicine, Madhukar Rainbow Children's Hospital, New Delhi, India
| | - Amit Aggarwal
- Department of Pediatric Nephrology, Madhukar Rainbow Children's Hospital, New Delhi, India
| | - Anil Batra
- Department of Neonatology, Madhukar Rainbow Children's Hospital, New Delhi, India
| | - Anurag Sharma
- Department of Pediatric Neurosurgery, Madhukar Rainbow Children's Hospital, New Delhi, India
| | - Jayasree Sundar
- Department of Obstetrics and Gynecology, Madhukar Rainbow Children's Hospital, New Delhi, India
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Florea L, Caba L, Gorduza EV. Genetic Heterogeneity in Bartter Syndrome: Clinical and Practical Importance. Front Pediatr 2022; 10:908655. [PMID: 35722471 PMCID: PMC9203713 DOI: 10.3389/fped.2022.908655] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 04/21/2022] [Indexed: 11/13/2022] Open
Abstract
Bartter syndrome (BS) is a rare tubulopathy that causes polyuria, hypokalemia, hypochloremic metabolic alkalosis, and normotensive hyperreninemic hyperaldosteronism. It is characterized by locus, clinical, and allelic heterogeneity. Types 1-4 of BS are inherited according to an autosomal recessive pattern, while type 5, which is transient, is X linked. There are specific correlations between the clinical expression and the molecular defect, but since it is a rare disease, such studies are rare. Therapeutic interventions are different, being correlated with types of BS.
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Affiliation(s)
- Laura Florea
- Department of Nephrology-Internal Medicine, Faculty of Medicine, "Grigore T. Popa" University of Medicine and Pharmacy, Iasi, Romania
| | - Lavinia Caba
- Department of Medical Genetics, Faculty of Medicine, "Grigore T. Popa" University of Medicine and Pharmacy, Iasi, Romania
| | - Eusebiu Vlad Gorduza
- Department of Medical Genetics, Faculty of Medicine, "Grigore T. Popa" University of Medicine and Pharmacy, Iasi, Romania
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Urwin S, Willows J, Sayer JA. The challenges of diagnosis and management of Gitelman syndrome. Clin Endocrinol (Oxf) 2020; 92:3-10. [PMID: 31578736 DOI: 10.1111/cen.14104] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 08/13/2019] [Accepted: 09/18/2019] [Indexed: 12/21/2022]
Abstract
Gitelman syndrome is an inherited tubulopathy characterized by renal salt wasting from the distal convoluted tubule. Defects in the sodium chloride cotransporter (encoded by SLC12A3) underlie this autosomal recessive condition. This article focuses on the specific challenges of diagnosing and treating Gitelman syndrome, with use of an illustrative case report. Symptoms relate to decreased serum potassium and magnesium levels, which include muscle weakness, tetany, fatigue and palpitations. Sudden cardiac deaths have been reported. Making a diagnosis may be difficult given its rarity but is important. A knowledge of the serum and urine biochemical picture is vital to distinguish it from a broad differential diagnosis, and application of genetic testing can resolve difficult cases. There is a group of Gitelman syndrome heterozygous carriers that experience symptoms and electrolyte disturbance and these patients should be managed in a similar way, though here genetic investigations become key in securing a difficult diagnosis. Potassium and magnesium replacement is the cornerstone of treatment, though practically this can be hard for patients to manage and often does not fully relieve symptoms even when serum levels are normalized. Challenges arise due to the lack of randomized controlled trials focussing on treatment of this rare disease; hence, clinicians endorse strategies in line with correction of the underlying pathophysiology such as sodium loading or pharmacological treatments, which seem to help some patients. Focussed dietary advice and knowing the best tolerated preparations of potassium and magnesium medications are useful tools for the physician, as well as an awareness of the specific burdens that this patient group face in order to signpost appropriate support.
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Affiliation(s)
- Stephanie Urwin
- Renal Services, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Jamie Willows
- Renal Services, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - John A Sayer
- Renal Services, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
- Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne, UK
- NIHR Newcastle Biomedical Research Centre, Newcastle University, Newcastle upon Tyne, UK
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Abstract
Bartter syndrome is an inherited renal tubular disorder caused by a defective salt reabsorption in the thick ascending limb of loop of Henle, resulting in salt wasting, hypokalemia, and metabolic alkalosis. Mutations of several genes encoding the transporters and channels involved in salt reabsorption in the thick ascending limb cause different types of Bartter syndrome. A poor phenotype-genotype relationship due to the interaction with other cotransporters and different degrees of compensation through alternative pathways is currently reported. However, phenotypic identification still remains the first step to guide the suspicion of Bartter syndrome. Given the rarity of the syndrome, and the lack of genetic characterization in most cases, limited clinical evidence for treatment is available and the therapy is based mainly on the comprehension of renal physiology and relies on the physician's personal experiences. A better understanding of the mutated channels and transporters could possibly generate targets for specific treatment in the future, also encompassing drugs aiming to correct deficiencies in folding or plasma membrane expression of the mutated proteins.
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Affiliation(s)
- Tamara da Silva Cunha
- Nephrology Division, Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, São Paulo, Brazil,
| | - Ita Pfeferman Heilberg
- Nephrology Division, Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, São Paulo, Brazil,
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Abstract
PURPOSE OF REVIEW Antenatal Bartter syndrome (aBS) is a heterogenous disease resulting from defective ion transport in the thick ascending limb of the loop of Henle. Novel insights into the pathophysiology, as well as the recent identification of a novel genetic cause of aBS, merit an update on this topic. RECENT FINDINGS In aBS, severe salt losing is further aggravated by defective salt sensing in the macula densa, where a reduced tubular salt concentration is perceived and glomerular filtration is increased instead of decreased. As patients with aBS come of age, there is an increased incidence of proteinuria and impaired renal function.Moreover, we recently reported a new form of aBS. Indeed, we described a series of nine families in whom pregnancies with male fetuses where complicated by acute polyhydramnios, preterm delivery and with severe but transient polyuria. We identified mutations in melanoma-associated antigen D2 in all study participants and showed, in vivo and in vitro, reduced expression of the furosemide and thiazide sensitive transporters sodium-potassium-2-chloride cotransporter and sodium chloride cotransporter, respectively. SUMMARY Genetic studies revealed the complexity of ion transport in the thick ascending limb of the loop of Henle and will help to clarify the pathophysiology, which is essential to design new therapies.
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Peng X, Jiang L, Chen C, Qin Y, Yuan T, Wang O, Xing X, Li X, Nie M, Chen L. Increased urinary prostaglandin E2 metabolite: A potential therapeutic target of Gitelman syndrome. PLoS One 2017; 12:e0180811. [PMID: 28700713 PMCID: PMC5507263 DOI: 10.1371/journal.pone.0180811] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/21/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Gitelman syndrome (GS), an inherited autosomal recessive salt-losing renal tubulopathy caused by mutations in SLC12A3 gene, has been associated with normal prostaglandin E2 (PGE2) levels since 1995 by a study involving 11 clinically diagnosed patients. However, it is difficult to explain why cyclooxygenase-2 (COX2) inhibitors, which pharmacologically reduce PGE2 synthesis, are helpful to patients with GS, and few studies performed in the last 20 years have measured PGE2 levels. The relationships between the clinical manifestations and PGE2 levels were never thoroughly analyzed. METHODS This study involved 39 GS patients diagnosed by SLC12A3 gene sequencing. Plasma and 24-h urine samples as well as the clinical data were collected at admission. PGE2 and PGEM levels were detected in plasma and urine samples by enzyme immunoassays. The in vivo function of the sodium-chloride co-transporter (NCC) in GS patients was evaluated using a modified thiazide test. The association among PGE2 levels, clinical manifestations and the function of NCC in GS patients were analyzed. RESULTS Significantly higher levels of urinary and plasma PGEM were observed in GS patients than in the healthy volunteers. Higher urinary PGEM levels indicated more severe clinical manifestations and NCC dysfunction estimated by the increase of Cl- clearance. A higher PGEM level was found in male GS patients, who showed earlier onset age and more severe hypokalemia, hypochloremia and metabolic alkalosis than female GS patients. No relationship between renin angiotensin aldosterone system activation and PGEM level was observed. CONCLUSIONS Higher urinary PGEM levels indicated more severe clinical manifestations and NCC dysfunction in GS patients. COX2 inhibition might be a potential therapeutic target in GS patients with elevated PGEM levels.
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Affiliation(s)
- Xiaoyan Peng
- Department of Nephrology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Lanping Jiang
- Department of Nephrology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Chen Chen
- Department of Nephrology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- State Key Laboratory of Medical Genetics, Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Yan Qin
- Department of Nephrology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Tao Yuan
- Department of Endocrinology & Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Ou Wang
- Department of Endocrinology & Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiaoping Xing
- Department of Endocrinology & Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xuemei Li
- Department of Nephrology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Min Nie
- Department of Endocrinology & Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Limeng Chen
- Department of Nephrology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- * E-mail:
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Hofmeister AF, Kömhoff M, Weber S, Grgic I. Disease modeling in genetic kidney diseases: mice. Cell Tissue Res 2017; 369:159-170. [PMID: 28601904 DOI: 10.1007/s00441-017-2639-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 05/04/2017] [Indexed: 12/27/2022]
Abstract
The mouse still represents arguably the most important mammal organism in research for modeling human genetic kidney diseases in vivo. Compared with many other mammal species, the breeding and maintenance of mice in the laboratory is relatively simple and cheap and reproduction cycles are short. In addition to classic gene knockout mouse lines, new molecular biological technologies have led to the development of a plethora of other, more sophisticated, mouse models, allowing the targeting of genes or gene function in a cell-specific, tissue-specific and time-dependent fashion. With the refinement of more recently developed genome-editing technologies, including the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system and other engineered nucleases such as zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs), our "tool set" of mouse models is expected to rapidly expand. These technological advances hold great promise and should enable us to study and hence understand the biology of inherited kidney diseases in greater detail. By analogy, we may be able to answer questions regarding the impact of individual proteins on the development of human kidney disorders, the underlying mechanisms governing the evolution of the disease and the predicted responsiveness to therapeutic interventions. Moreover, knockout and transgenic mouse models can be highly informative with respect to the effects of genetic variations on renal phenotypes. This review focuses on mouse models that have been devised primarily to study monogenic human kidney diseases, which are typically caused by a single abnormal gene and passed on in a Mendelian pattern. Despite the large number of human hereditary kidney disorders and the multitude of mouse models described in the literature, we attempt to give a balanced overview of several well-known renal pathologies, a few of which are addressed in some detail.
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Affiliation(s)
- Andreas F Hofmeister
- Department of Internal Medicine and Nephrology, University Hospital Giessen and Marburg, Philipps-University Marburg, Baldingerstrasse 1, 35033, Marburg, Germany
| | - Martin Kömhoff
- University Children's Hospital, Philipps-University Marburg, Marburg, Germany
| | - Stefanie Weber
- University Children's Hospital, Philipps-University Marburg, Marburg, Germany
| | - Ivica Grgic
- Department of Internal Medicine and Nephrology, University Hospital Giessen and Marburg, Philipps-University Marburg, Baldingerstrasse 1, 35033, Marburg, Germany.
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Cha EJ, Hwang WM, Yun SR, Park MH. An Adult Case of Bartter Syndrome Type III Presenting with Proteinuria. J Pathol Transl Med 2016; 50:160-4. [PMID: 26755355 PMCID: PMC4804144 DOI: 10.4132/jptm.2015.08.31] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 08/04/2015] [Accepted: 08/31/2015] [Indexed: 11/18/2022] Open
Abstract
Bartter syndrome (BS) I–IV is a rare autosomal recessive disorder affecting salt reabsorption in the thick ascending limb of the loop of Henle. This report highlights clinicopathological findings and genetic studies of classic BS in a 22-year-old female patient who presented with persistent mild proteinuria for 2 years. A renal biopsy demonstrated a mild to moderate increase in the mesangial cells and matrix of most glomeruli, along with marked juxtaglomerular cell hyperplasia. These findings suggested BS associated with mild IgA nephropathy. Focal tubular atrophy, interstitial fibrosis, and lymphocytic infiltration were also observed. A genetic study of the patient and her parents revealed a mutation of the CLCNKB genes. The patient was diagnosed with BS, type III. This case represents an atypical presentation of classic BS in an adult patient. Pathologic findings of renal biopsy combined with genetic analysis and clinicolaboratory findings are important in making an accurate diagnosis.
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Affiliation(s)
- Eun Jung Cha
- Department of Pathology, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea
| | - Won Min Hwang
- Division of Nephrology, Department of Internal Medicine, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea
| | - Sung-Ro Yun
- Division of Nephrology, Department of Internal Medicine, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea
| | - Moon Hyang Park
- Department of Pathology, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea
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Ionenkanalerkrankungen der Niere und Nebenniere. MED GENET-BERLIN 2013. [DOI: 10.1007/s11825-013-0423-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Zusammenfassung
Genetische Nierenerkrankungen haben an den sich im Kindes- bis Jugendalter manifestierenden Nierenerkrankungen einen bedeutenden Anteil, gewinnen aber auch zunehmend an Bedeutung für nur langsam progrediente oder spät im Erwachsenenalter auftretende Erkrankungen. Ein erheblicher Teil insbesondere kindlicher Nierenerkrankungen ist mit terminaler Niereninsuffizienz und/oder weiterer relevanter Morbidität verbunden. Eine frühzeitige (molekulare) Diagnosestellung kann für eine bessere prognostische Einschätzung Voraussetzung sein und bietet Möglichkeiten hinsichtlich einer optimierten symptomatischen Therapie.
Mechanistisch betrachtet stellen mit Mutationen in Ionenkanälen assoziierte Nephropathien – neben strukturellen Defekten des glomerulären Filters (z. B. COL4A3, LAMB2, Nephrin) und Störungen der für die Entwicklung des Urogenitaltrakts relevanter Signalwege (z. B. HNF1B, WT1) – eine prototypische und zahlenmäßig wesentliche Gruppe dar.
Die molekulargenetische Aufklärung der (hypokaliämischen) Salzverlusttubulopathien hat ganz wesentlich zu unserem Verständnis der zentralen Rolle der Niere im Salzhaushalt beigetragen. Das Spektrum renaler Ionenkanalerkrankungen soll an den Beispielen der klassischen Salzverlusttubulopathien (Bartter- und Gitelman-Syndrom), der Transient-receptor-potential-(TRP)-Kanalgruppe sowie der Rolle von Kanalveränderungen bei Aldosteronismus und angeborenen Hypertonusformen dargestellt werden.
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Castrop H, Höcherl K, Kurtz A, Schweda F, Todorov V, Wagner C. Physiology of Kidney Renin. Physiol Rev 2010; 90:607-73. [PMID: 20393195 DOI: 10.1152/physrev.00011.2009] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The protease renin is the key enzyme of the renin-angiotensin-aldosterone cascade, which is relevant under both physiological and pathophysiological settings. The kidney is the only organ capable of releasing enzymatically active renin. Although the characteristic juxtaglomerular position is the best known site of renin generation, renin-producing cells in the kidney can vary in number and localization. (Pro)renin gene transcription in these cells is controlled by a number of transcription factors, among which CREB is the best characterized. Pro-renin is stored in vesicles, activated to renin, and then released upon demand. The release of renin is under the control of the cAMP (stimulatory) and Ca2+(inhibitory) signaling pathways. Meanwhile, a great number of intrarenally generated or systemically acting factors have been identified that control the renin secretion directly at the level of renin-producing cells, by activating either of the signaling pathways mentioned above. The broad spectrum of biological actions of (pro)renin is mediated by receptors for (pro)renin, angiotensin II and angiotensin-( 1 – 7 ).
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Affiliation(s)
- Hayo Castrop
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Klaus Höcherl
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Armin Kurtz
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Frank Schweda
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Vladimir Todorov
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Charlotte Wagner
- Institute of Physiology, University of Regensburg, Regensburg, Germany
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Iyer JP, Srivastava PK, Dev R, Dastidar SG, Ray A. Prostaglandin E(2) synthase inhibition as a therapeutic target. Expert Opin Ther Targets 2009; 13:849-65. [PMID: 19530988 DOI: 10.1517/14728220903018932] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Most NSAIDs function by inhibiting biosynthesis of PGE(2) by inhibition of COX-1 and/or COX-2. Since COX-1 has a protective function in the gastro-intestinal tract (GIT), non-selective inhibition of both cycloxy genases leads to moderate to severe gastro-intestinal intolerance. Attempts to identify selective inhibitors of COX-2, led to the identification of celecoxib and rofecoxib. However, long-term use of these drugs has serious adverse effects of sudden myocardial infarction and thrombosis. Drug-mediated imbalance in the levels of prostaglandin I(2) (PGI(2)) and thromboxane A(2) (TXA(2)) with a bias towards TXA(2) may be the primary reason for these events. This resulted in the drugs being withdrawn from the market, leaving a need for an effective and safe anti-inflammatory drug. METHODS Recently, the focus of research has shifted to enzymes downstream of COX in the prosta glandin biosynthetic pathway such as prostaglandin E(2) synthases. Microsomal prostaglandin E(2) synthase-1 (mPGES-1) specifically isomerizes PGH(2) to PGE(2), under inflammatory conditions. In this review, we examine the biology of mPGES-1 and its role in disease. Progress in designing molecules that can selectively inhibit mPGES-1 is reviewed. CONCLUSION mPGES-1 has the potential to be a target for anti-inflammatory therapy, devoid of adverse GIT and cardiac effects and warrants further investigation.
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Affiliation(s)
- Jitesh P Iyer
- Department of Pharmacology, New Drug Discovery Research, Ranbaxy Research Laboratories, Plot No-20, Sector-18, Udyog Vihar, Gurgaon, Haryana, India-122015
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Radi ZA, Ostroski R. Pulmonary and cardiorenal cyclooxygenase-1 (COX-1), -2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1) and -2 (mPGES-2) expression in a hypertension model. Mediators Inflamm 2008; 2007:85091. [PMID: 17641732 PMCID: PMC1906712 DOI: 10.1155/2007/85091] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2007] [Accepted: 03/16/2007] [Indexed: 11/18/2022] Open
Abstract
Hypertensive mice that express the human renin and angiotensinogen genes are used as a model for human hypertension because they develop hypertension secondary to increased renin-angiotensin system activity. Our study investigated the cellular localization and distribution of COX-1, COX-2, mPGES-1, and mPGES-2 in organ tissues from a mouse model of human hypertension. Male (n = 15) and female (n = 15) double transgenic mice (h-Ang 204/1 h-Ren 9) were used in the study. Lung, kidney, and heart tissues were obtained from mice at necropsy and fixed in 10% neutral buffered formalin followed by embedding in paraffin wax. Cut sections were stained immunohistochemically with antibodies to COX-1, COX-2, mPGES-1, and mPGES-2 and analyzed by light microscopy. Renal expression of COX-1 was the highest in the distal convoluted tubules, cortical collecting ducts, and medullary collecting ducts; while proximal convoluted tubules lacked COX-1 expression. Bronchial and bronchiolar epithelial cells, alveolar macrophages, and cardiac vascular endothelial cells also had strong COX-1 expression, with other renal, pulmonary, or cardiac microanatomic locations having mild-to-moderate expression. mPGES-2 expression was strong in the bronchial and bronchiolar epithelial cells, mild to moderate in various renal microanatomic locations, and absent in cardiac tissues. COX-2 expression was strong in the proximal and distal convoluted tubules, alveolar macrophages, and bronchial and bronchiolar epithelial cells. Marked mPGES-1 was present only in bronchial and bronchiolar epithelial cells; while mild-to-moderate expression was present in other pulmonary, renal, or cardiac microanatomic locations. Expression of these molecules was similar between males and females. Our work suggests that in hypertensive mice, there are (a) significant microanatomic variations in the pulmonary, renal, and cardiac distribution and cellular localization of COX-1, COX-2, mPGES-1, and mPGES-2, and (b) no differences in expression between genders.
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Affiliation(s)
- Zaher A. Radi
- Drug Safety Research & Development, Pfizer Global Research and Development, 2800 Plymouth Road, Building 50-G0503,
Ann Arbor, MI 48105, USA
- *Zaher A. Radi:
| | - Robert Ostroski
- Department of Cardiovascular Pharmacology, Pfizer Global Research and Development, 2800 Plymouth Road,
Building 50-G0503, Ann Arbor, MI 48105, USA
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13
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Samuelsson B, Morgenstern R, Jakobsson PJ. Membrane prostaglandin E synthase-1: a novel therapeutic target. Pharmacol Rev 2007; 59:207-24. [PMID: 17878511 DOI: 10.1124/pr.59.3.1] [Citation(s) in RCA: 402] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Prostaglandin E(2) (PGE(2)) is the most abundant prostaglandin in the human body. It has a large number of biological actions that it exerts via four types of receptors, EP1-4. PGE(2) is formed from arachidonic acid by cyclooxygenase (COX-1 and COX-2)-catalyzed formation of prostaglandin H(2) (PGH(2)) and further transformation by PGE synthases. The isomerization of the endoperoxide PGH(2) to PGE(2) is catalyzed by three different PGE synthases, viz. cytosolic PGE synthase (cPGES) and two membrane-bound PGE synthases, mPGES-1 and mPGES-2. Of these isomerases, cPGES and mPGES-2 are constitutive enzymes, whereas mPGES-1 is mainly an induced isomerase. cPGES uses PGH(2) produced by COX-1 whereas mPGES-1 uses COX-2-derived endoperoxide. mPGES-2 can use both sources of PGH(2). mPGES-1 is a member of the membrane associated proteins involved in eicosanoid and glutathione metabolism (MAPEG) superfamily. It requires glutathione as an essential cofactor for its activity. mPGES-1 is up-regulated in response to various proinflammatory stimuli with a concomitant increased expression of COX-2. The coordinate increased expression of COX-2 and mPGES-1 is reversed by glucocorticoids. Differences in the kinetics of the expression of the two enzymes suggest distinct regulatory mechanisms for their expression. Studies, mainly from disruption of the mPGES-1 gene in mice, indicate key roles of mPGES-1-generated PGE(2) in female reproduction and in pathological conditions such as inflammation, pain, fever, anorexia, atherosclerosis, stroke, and tumorigenesis. These findings indicate that mPGES-1 is a potential target for the development of therapeutic agents for treatment of several diseases.
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Affiliation(s)
- Bengt Samuelsson
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 77, Stockholm, Sweden.
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Abstract
Prostaglandin E (PGE)(2) is a major arachidonic acid metabolite in a wide variety of tissues and is implicated in the control of inflammatory as well as physiological responses. At least three major forms of PGE synthase (PGES) have recently been cloned and characterized: membrane-associated PGES (mPGES)-1, mPGES-2, and cytosolic PGES (cPGES). Among them, mPGES-1 is highly inducible by cytokine and is critically involved in pain and inflammatory responses. Emerging evidence suggests that mPGES-1 may also participate in blood pressure (BP) regulation through an impact on renal and vascular functions. Within the kidney, mPGES-1 predominates in the distal nephron where its expression is highly inducible by salt loading. Mice lacking mPGES-1 exhibit blunted natriuretic response paralleled with remarkably suppressed nitric oxide production, leading to salt-sensitive hypertension. These mice also exhibit an exaggerated hypertensive response to angiotensin II infusion. Together, these results suggest that mPGES-1 may be an important physiological regulator of BP.
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Affiliation(s)
- T Yang
- Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah 84132, USA.
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Yang G, Chen L, Zhang Y, Zhang X, Wu J, Li S, Wei M, Zhang Z, Breyer MD, Guan Y. Expression of mouse membrane-associated prostaglandin E2 synthase-2 (mPGES-2) along the urogenital tract. Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:1459-68. [PMID: 17064959 DOI: 10.1016/j.bbalip.2006.06.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Revised: 06/09/2006] [Accepted: 06/12/2006] [Indexed: 11/19/2022]
Abstract
Prostaglandin E(2) (PGE(2)) is the most common prostanoid and has a variety of bioactivities including a crucial role in urogenital function. Multiple enzymes are involved in its biosynthesis. Among 3 PGE(2) terminal synthetic enzymes, membrane-associated PGE(2) synthase-2 (mPGES-2) is the most recently identified, and its role remains uncharacterized. In previous studies, membrane-associated PGE(2) synthase-1 (mPGES-1) and cytosolic PGE(2) synthase (cPGES) were reported to be expressed along the urogenital tracts. Here we report the genomic structure and tissue distribution of mPGES-2 in the urogenital system. Analysis of several bioinformatic databases demonstrated that mouse mPGES-2 spans 7 kb and consists of 7 exons. The mPGES-2 promoter contains multiple Sp1 sites and a GC box without a TATA box motif. Real-time quantitative PCR revealed that constitutive mPGES-2 mRNA was most abundant in the heart, brain, kidney and small intestine. In the urogenital system, mPGES-2 was highly expressed in the renal cortex, followed by the renal medulla and ovary, with lower levels in the ureter, bladder and uterus. Immunohistochemistry studies indicated that mPGES-2 was ubiquitously expressed along the nephron, with much lower levels in the glomeruli. In the ureter and bladder, mPGES-2 was mainly localized to the urothelium. In the reproductive system, mPGES-2 was restricted to the epithelial cells of the testis, epididymis, vas deferens and seminal vesicle in males, and oocytes, stroma cells and corpus luteum of the ovary and epithelial cells of the oviduct and uterus in females. This expression pattern is consistent with an important role for mPGES-2-mediated PGE(2) in urogenital function.
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Affiliation(s)
- Guangrui Yang
- Department of Physiology and Pathophysiology, Health Science Center, Peking University, Beijing 100083, China
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16
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Kömhoff M, Klaus G, Nazarowa S, Reinalter SC, Seyberth HW. Increased systolic blood pressure with rofecoxib in congenital furosemide-like salt loss. Nephrol Dial Transplant 2006; 21:1833-7. [PMID: 16554326 DOI: 10.1093/ndt/gfl096] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND To analyse whether congenital furosemide- or thiazide-like renal salt loss protects against the potential prohypertensive effects of two cyclooxygenase (COX) inhibitors: rofecoxib, a COX-2 selective inhibitor, and indomethacin, an unselective COX-inhibitor. METHODS In a retrospective analysis, the effects of rofecoxib and indomethacin on blood pressure (bp: transformed into age-independent standard deviation scores (SDS) values), creatinine clearance (CRC), fractional excretion of sodium (FeNa), and renal excretion of systemic prostaglandins were studied in 28 patients with a genetically proven congenital hypokalaemic salt-losing tubulopathy (SLT) (11 female and 17 male, age: 2-25 years), 19 with a furosemide-like SLT, and nine with a thiazide-like SLT. RESULTS In furosemide-like SLT patients, systolic SDS bp values were significantly higher with rofecoxib (1.03 +/- 0.16 SDS, n = 107) compared with indomethacin (0.56 +/- 0.09 SDS, n = 282; P = 0.007, 95% CI: 0.12-0.8). Without the drugs, systolic SDS bp values were elevated by 0.63 +/- 0.11 SDS, n = 164. Both drugs reduced renin and aldosterone-plasma levels to a similar extent. SDS values were significantly correlated with the excretion of the vasoconstrictor thromboxane (T x B2) (R2: 0.038, P = 0.021, n: 159), but not with CRC or FeNa. Blood pressure was not increased in thiazide-like SLT patients treated with rofecoxib. CONCLUSION Congenital furosemide-like renal salt loss does not protect against the prohypertensive effects of rofecoxib. The positive correlation between bp SDS values with T x B2 but not with FeNa or CRC point towards an altered vascular homeostasis as one mechanism increasing blood pressure.
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Affiliation(s)
- Martin Kömhoff
- Department of Pediatrics, Philipps University Marburg, D-35033 Marburg, Germany.
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Kömhoff M, Tekesin I, Peters M, Leonhard A, Seyberth HW. Perinatal management of a preterm neonate affected by hyperprostaglandin E2 syndrome (HPS). Acta Paediatr 2005; 94:1690-3. [PMID: 16303714 DOI: 10.1080/08035250510043897] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Neonates affected by hyperprostaglandin E(2) syndrome (HPS) present with severe polyuria. Both urinary losses as well as prostaglandin synthesis inhibitors may precipitate acute renal failure (ARF). AIM Our goal was to maintain euvolaemia by replacement of urinary losses. PATIENT Our patient was born prematurely with a family history typical of HPS. Urinary salt and water losses and PGE(2) excretion were determined in 2- to 4-h intervals. Salt and water were replaced accordingly. RESULTS Within the first 48 h, urinary losses and PGE(2) increased continuously to 50 ml/kg/h and 374 ng/h/1.73 m(2), respectively. Following exposure to 0.05-0.5 mg/kg/d indomethacin, urinary output decreased steadily to 10-15/ml/kg/h. CONCLUSION In euvolaemic preterm neonates with HPS and the need for excessive replacement of salt and water, inhibition of renal PGE(2) excretion with indomethacin effectively reduces polyuria and natriuresis without acutely compromising renal function.
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Affiliation(s)
- Martin Kömhoff
- Department of Paediatrics, Philipps University Marburg, Marburg, Germany.
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Jeck N, Schlingmann KP, Reinalter SC, Kömhoff M, Peters M, Waldegger S, Seyberth HW. Salt handling in the distal nephron: lessons learned from inherited human disorders. Am J Physiol Regul Integr Comp Physiol 2005; 288:R782-95. [PMID: 15793031 DOI: 10.1152/ajpregu.00600.2004] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The molecular basis of inherited salt-losing tubular disorders with secondary hypokalemia has become much clearer in the past two decades. Two distinct segments along the nephron turned out to be affected, the thick ascending limb of Henle's loop and the distal convoluted tubule, accounting for two major clinical phenotypes, hyperprostaglandin E syndrome and Bartter-Gitelman syndrome. To date, inactivating mutations have been detected in six different genes encoding for proteins involved in renal transepithelial salt transport. Careful examination of genetically defined patients (“human knockouts”) allowed us to determine the individual role of a specific protein and its contribution to the overall process of renal salt reabsorption. The recent generation of several genetically engineered mouse models that are deficient in orthologous genes further enabled us to compare the human phenotype with the animal models, revealing some unexpected interspecies differences. As the first line treatment in hyperprostaglandin E syndrome includes cyclooxygenase inhibitors, we propose some hypotheses about the mysterious role of PGE2in the etiology of renal salt-losing disorders.
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Affiliation(s)
- Nikola Jeck
- MD, Univ. Children's Hospital, Philipps-Univ., Deutschhausstrasse 12, D-35037 Marburg, Germany. )
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