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Saikumar P, Sadauskas M, Izhar S, Moshiree B, Patel D. Constipation and DIOS: Diagnosis, differential diagnosis, and management. Pediatr Pulmonol 2024; 59 Suppl 1:S81-S90. [PMID: 39105354 DOI: 10.1002/ppul.27104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 04/22/2024] [Accepted: 05/22/2024] [Indexed: 08/07/2024]
Abstract
Cystic Fibrosis (CF) is a complex disorder that requires multidisciplinary expertise for effective management. The GALAXY study estimated the prevalence of constipation to be about 25% among People with Cystic Fibrosis (PwCF), identifying it as one of the common gastrointestinal (GI) symptoms within this patient population. Quality of Life (QoL) assessments uncovered high patient dissatisfaction, highlighting the imperative need for enhanced treatment strategies. Similarly, Distal Intestinal Obstruction Syndrome (DIOS) is a unique condition exclusive to PwCF that, if left undiagnosed, can lead to considerable morbidity and mortality. Given the broad spectrum of differential diagnoses for abdominal pain, including constipation and DIOS, it is paramount for healthcare providers to possess a clear understanding of these conditions. This paper aims to delineate various differentials for abdominal pain while elucidating the pathogenesis, diagnostic criteria, and treatment options for managing constipation and DIOS in PwCF.
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Affiliation(s)
- Pavithra Saikumar
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Cardinal Glennon Children's Medical Center, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Marisa Sadauskas
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Sophia Izhar
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Baha Moshiree
- Atrium Health, Division of Gastroenterology, Hepatology and Nutrition, Wake Forest Medical University, Charlotte, North Carolina, USA
| | - Dhiren Patel
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Cardinal Glennon Children's Medical Center, Saint Louis University School of Medicine, St. Louis, Missouri, USA
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2
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Houser A, Baconguis I. Structural Insights into Subunit-Dependent Functional Regulation in Epithelial Sodium Channels. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.28.595834. [PMID: 38853903 PMCID: PMC11160588 DOI: 10.1101/2024.05.28.595834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Epithelial sodium channels (ENaC) play a crucial role in Na + reabsorption in mammals. To date, four subunits have been identified-α, β, γ, and δ-believed to form different heteromeric complexes. Currently, only the structure of the αβγ complex is known. To understand how these channels form with varying subunit compositions and define the contribution of each subunit to distinct properties, we co-expressed human δ, β, and γ. Using single-particle cryo-electron microscopy, we observed three distinct ENaC complexes. The structures unveil a pattern in which β and γ positions are conserved among the different complexes while the α position in αβγ trimer is occupied by either δ or another β. The presence of δ induces structural rearrangements in the γ subunit explaining the differences in channel activity observed between αβγ and δβγ channels. These structures define the mechanism by which ENaC subunit composition tunes ENaC function.
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3
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Ahn Y, Park JH. Novel Potential Therapeutic Targets in Autosomal Dominant Polycystic Kidney Disease from the Perspective of Cell Polarity and Fibrosis. Biomol Ther (Seoul) 2024; 32:291-300. [PMID: 38589290 PMCID: PMC11063481 DOI: 10.4062/biomolther.2023.207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/18/2023] [Accepted: 12/26/2023] [Indexed: 04/10/2024] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD), a congenital genetic disorder, is a notable contributor to the prevalence of chronic kidney disease worldwide. Despite the absence of a complete cure, ongoing research aims for early diagnosis and treatment. Although agents such as tolvaptan and mTOR inhibitors have been utilized, their effectiveness in managing the disease during its initial phase has certain limitations. This review aimed to explore new targets for the early diagnosis and treatment of ADPKD, considering ongoing developments. We particularly focus on cell polarity, which is a key factor that influences the process and pace of cyst formation. In addition, we aimed to identify agents or treatments that can prevent or impede the progression of renal fibrosis, ultimately slowing its trajectory toward end-stage renal disease. Recent advances in slowing ADPKD progression have been examined, and potential therapeutic approaches targeting multiple pathways have been introduced. This comprehensive review discusses innovative strategies to address the challenges of ADPKD and provides valuable insights into potential avenues for its prevention and treatment.
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Affiliation(s)
- Yejin Ahn
- Department of Biological Sciences, Sookmyung Women’s University, Seoul, 04310, 04310, Republic of Korea
| | - Jong Hoon Park
- Department of Biological Sciences, Sookmyung Women’s University, Seoul, 04310, 04310, Republic of Korea
- Research Institute of Women’s Health, Sookmyung Women’s University, Seoul, 04310, Republic of Korea
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4
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Ríos-Medina Y, Rico-Chávez P, Martínez-Vieyra I, Durán-Álvarez JC, Rodriguez-Varela M, Rincón-Heredia R, Reyes-López C, Cerecedo D. Altered Plasma Membrane Lipid Composition in Hypertensive Neutrophils Impacts Epithelial Sodium Channel (ENaC) Endocytosis. Int J Mol Sci 2024; 25:4939. [PMID: 38732158 PMCID: PMC11084340 DOI: 10.3390/ijms25094939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/22/2024] [Accepted: 04/24/2024] [Indexed: 05/13/2024] Open
Abstract
Biological membranes are composed of a lipid bilayer with embedded proteins, including ion channels like the epithelial sodium channel (ENaC), which are critical for sodium homeostasis and implicated in arterial hypertension (HTN). Changes in the lipid composition of the plasma membrane can significantly impact cellular processes related to physiological functions. We hypothesized that the observed overexpression of ENaC in neutrophils from HTN patients might result from alterations in the structuring domains within the plasma membrane, disrupting the endocytic processes responsible for ENaC retrieval. This study assessed the structural lipid composition of neutrophil plasma membranes from HTN patients along with the expression patterns of key elements regulating ENaC at the plasma membrane. Our findings suggest alterations in microdomain structure and SGK1 kinase activity, which could prolong ENaC presence on the plasma membrane. Additionally, we propose that the proteasomal and lysosomal degradation pathways are insufficient to diminish ENaC presence at the plasma membrane in HTN. These results highlight the importance of understanding ENaC retrieval mechanisms and suggest that targeting these mechanisms could provide insights for developing drugs to prevent and treat HTN.
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Affiliation(s)
- Yolanda Ríos-Medina
- Laboratorio de Hematobiología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico City 07230, Mexico; (Y.R.-M.); (P.R.-C.); (I.M.-V.)
| | - Pedro Rico-Chávez
- Laboratorio de Hematobiología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico City 07230, Mexico; (Y.R.-M.); (P.R.-C.); (I.M.-V.)
| | - Ivette Martínez-Vieyra
- Laboratorio de Hematobiología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico City 07230, Mexico; (Y.R.-M.); (P.R.-C.); (I.M.-V.)
| | - Juan C. Durán-Álvarez
- Instituto de Ciencias Aplicadas y Tecnología, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (J.C.D.-Á.); (M.R.-V.)
| | - Mario Rodriguez-Varela
- Instituto de Ciencias Aplicadas y Tecnología, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (J.C.D.-Á.); (M.R.-V.)
| | - Ruth Rincón-Heredia
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico;
| | - César Reyes-López
- Laboratorio de Bioquímica Estructural, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico City 07230, Mexico;
| | - Doris Cerecedo
- Laboratorio de Hematobiología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico City 07230, Mexico; (Y.R.-M.); (P.R.-C.); (I.M.-V.)
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5
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Ha J, Park JH, Kim KJ, Kim JH, Jung KY, Lee J, Choi JH, Lee SH, Hong N, Lim JS, Park BK, Kim JH, Jung KC, Cho J, Kim MK, Chung CH. 2023 Korean Endocrine Society Consensus Guidelines for the Diagnosis and Management of Primary Aldosteronism. Endocrinol Metab (Seoul) 2023; 38:597-618. [PMID: 37828708 PMCID: PMC10765003 DOI: 10.3803/enm.2023.1789] [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: 07/25/2023] [Revised: 08/31/2023] [Accepted: 09/06/2023] [Indexed: 10/14/2023] Open
Abstract
Primary aldosteronism (PA) is a common, yet underdiagnosed cause of secondary hypertension. It is characterized by an overproduction of aldosterone, leading to hypertension and/or hypokalemia. Despite affecting between 5.9% and 34% of patients with hypertension, PA is frequently missed due to a lack of clinical awareness and systematic screening, which can result in significant cardiovascular complications. To address this, medical societies have developed clinical practice guidelines to improve the management of hypertension and PA. The Korean Endocrine Society, drawing on a wealth of research, has formulated new guidelines for PA. A task force has been established to prepare PA guidelines, which encompass epidemiology, pathophysiology, clinical presentation, diagnosis, treatment, and follow-up care. The Korean clinical guidelines for PA aim to deliver an evidence-based protocol for PA diagnosis, treatment, and patient monitoring. These guidelines are anticipated to ease the burden of this potentially curable condition.
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Affiliation(s)
- Jeonghoon Ha
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jung Hwan Park
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - Kyoung Jin Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Jung Hee Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Kyong Yeun Jung
- Department of Internal Medicine, Nowon Eulji Medical Center, Eulji University School of Medicine, Seoul, Korea
| | - Jeongmin Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jong Han Choi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Korea
| | - Seung Hun Lee
- Division of Endocrinology and Metabolism, Department of Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Namki Hong
- Department of Internal Medicine, Endocrine Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jung Soo Lim
- Department of Internal Medicine and Research Institute of Metabolism and Inflammation, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Byung Kwan Park
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jung-Han Kim
- Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyeong Cheon Jung
- Department of Pathology, Seoul National University College of Medicine, Seoul, Korea
| | - Jooyoung Cho
- Department of Laboratory Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Mi-kyung Kim
- Department of Internal Medicine, Inje University Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Choon Hee Chung
- Department of Internal Medicine and Research Institute of Metabolism and Inflammation, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - The Committee of Clinical Practice Guideline of Korean Endocrine Society
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
- Department of Internal Medicine, Nowon Eulji Medical Center, Eulji University School of Medicine, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
- Department of Internal Medicine, Endocrine Research Institute, Yonsei University College of Medicine, Seoul, Korea
- Department of Internal Medicine and Research Institute of Metabolism and Inflammation, Yonsei University Wonju College of Medicine, Wonju, Korea
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Department of Pathology, Seoul National University College of Medicine, Seoul, Korea
- Department of Laboratory Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea
- Department of Internal Medicine, Inje University Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - The Korean Adrenal Study Group of Korean Endocrine Society
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
- Department of Internal Medicine, Nowon Eulji Medical Center, Eulji University School of Medicine, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Korea
- Division of Endocrinology and Metabolism, Department of Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
- Department of Internal Medicine, Endocrine Research Institute, Yonsei University College of Medicine, Seoul, Korea
- Department of Internal Medicine and Research Institute of Metabolism and Inflammation, Yonsei University Wonju College of Medicine, Wonju, Korea
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Department of Pathology, Seoul National University College of Medicine, Seoul, Korea
- Department of Laboratory Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea
- Department of Internal Medicine, Inje University Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
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6
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Nickerson AJ, Mutchler SM, Sheng S, Cox NA, Ray EC, Kashlan OB, Carattino MD, Marciszyn AL, Winfrey A, Gingras S, Kirabo A, Hughey RP, Kleyman TR. Mice lacking γENaC palmitoylation sites maintain benzamil-sensitive Na+ transport despite reduced channel activity. JCI Insight 2023; 8:e172051. [PMID: 37707951 PMCID: PMC10721255 DOI: 10.1172/jci.insight.172051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 09/12/2023] [Indexed: 09/16/2023] Open
Abstract
Epithelial Na+ channels (ENaCs) control extracellular fluid volume by facilitating Na+ absorption across transporting epithelia. In vitro studies showed that Cys-palmitoylation of the γENaC subunit is a major regulator of channel activity. We tested whether γ subunit palmitoylation sites are necessary for channel function in vivo by generating mice lacking the palmitoylated cysteines (γC33A,C41A) using CRISPR/Cas9 technology. ENaCs in dissected kidney tubules from γC33A,C41A mice had reduced open probability compared with wild-type (WT) littermates maintained on either standard or Na+-deficient diets. Male mutant mice also had higher aldosterone levels than WT littermates following Na+ restriction. However, γC33A,C41A mice did not have reduced amiloride-sensitive Na+ currents in the distal colon or benzamil-induced natriuresis compared to WT mice. We identified a second, larger conductance cation channel in the distal nephron with biophysical properties distinct from ENaC. The activity of this channel was higher in Na+-restricted γC33A,C41A versus WT mice and was blocked by benzamil, providing a possible compensatory mechanism for reduced prototypic ENaC function. We conclude that γ subunit palmitoylation sites are required for prototypic ENaC activity in vivo but are not necessary for amiloride/benzamil-sensitive Na+ transport in the distal nephron or colon.
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Affiliation(s)
| | | | | | | | | | - Ossama B. Kashlan
- Department of Medicine
- Department of Computational and Systems Biology
| | | | | | | | - Sebastien Gingras
- Department of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Annet Kirabo
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | | | - Thomas R. Kleyman
- Department of Medicine
- Department of Cell Biology, and
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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7
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Baris Feldman H, Chai Gadot C, Zahler D, Mory A, Aviram G, Elhanan E, Shefer G, Goldiner I, Amir Y, Kurolap A, Ablin JN. Corin and Left Atrial Cardiomyopathy, Hypertension, Arrhythmia, and Fibrosis. N Engl J Med 2023; 389:1685-1692. [PMID: 37913506 DOI: 10.1056/nejmoa2301908] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Two siblings presented with cardiomyopathy, hypertension, arrhythmia, and fibrosis of the left atrium. Each had a homozygous null variant in CORIN, the gene encoding atrial natriuretic peptide (ANP)-converting enzyme. A plasma sample obtained from one of the siblings had no detectable levels of corin or N-terminal pro-ANP but had elevated levels of B-type natriuretic peptide (BNP) and one of the two protein markers of fibrosis that we tested. These and other findings support the hypothesis that BNP cannot fully compensate for a lack of activation of the ANP pathway and that corin is critical to normal ANP activity, left atrial function, and cardiovascular homeostasis.
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Affiliation(s)
- Hagit Baris Feldman
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Chofit Chai Gadot
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - David Zahler
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Adi Mory
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Galit Aviram
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Emil Elhanan
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Gabi Shefer
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Ilana Goldiner
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Yam Amir
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Alina Kurolap
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
| | - Jacob N Ablin
- From the Genetics Institute and Genomics Center (H.B.F., C.C.G., A.M., E.E., Y.A., A.K.), the Departments of Cardiology (D.Z.), Radiology (G.A.), Nephrology (E.E.), Clinical Laboratories (G.S., I.G.), and Internal Medicine H (J.N.A.) and the Institute of Rheumatology (J.N.A.), Tel Aviv Sourasky Medical Center, and the Faculty of Medicine, Tel Aviv University (H.B.F., D.Z., G.A., I.G., Y.A., J.N.A.) - all in Tel Aviv, Israel
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8
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Sukhoplyasova M, Keith AM, Perrault EM, Vorndran HE, Jordahl AS, Yates ME, Pastor A, Li Z, Freaney ML, Deshpande RA, Adams DB, Guerriero CJ, Shi S, Kleyman TR, Kashlan OB, Brodsky JL, Buck TM. Lhs1 dependent ERAD is determined by transmembrane domain context. Biochem J 2023; 480:1459-1473. [PMID: 37702403 PMCID: PMC11040695 DOI: 10.1042/bcj20230075] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 09/14/2023]
Abstract
Transmembrane proteins have unique requirements to fold and integrate into the endoplasmic reticulum (ER) membrane. Most notably, transmembrane proteins must fold in three separate environments: extracellular domains fold in the oxidizing environment of the ER lumen, transmembrane domains (TMDs) fold within the lipid bilayer, and cytosolic domains fold in the reducing environment of the cytosol. Moreover, each region is acted upon by a unique set of chaperones and monitored by components of the ER associated quality control machinery that identify misfolded domains in each compartment. One factor is the ER lumenal Hsp70-like chaperone, Lhs1. Our previous work established that Lhs1 is required for the degradation of the unassembled α-subunit of the epithelial sodium channel (αENaC), but not the homologous β- and γENaC subunits. However, assembly of the ENaC heterotrimer blocked the Lhs1-dependent ER associated degradation (ERAD) of the α-subunit, yet the characteristics that dictate the specificity of Lhs1-dependent ERAD substrates remained unclear. We now report that Lhs1-dependent substrates share a unique set of features. First, all Lhs1 substrates appear to be unglycosylated, and second they contain two TMDs. Each substrate also contains orphaned or unassembled TMDs. Additionally, interfering with inter-subunit assembly of the ENaC trimer results in Lhs1-dependent degradation of the entire complex. Finally, our work suggests that Lhs1 is required for a subset of ERAD substrates that also require the Hrd1 ubiquitin ligase. Together, these data provide hints as to the identities of as-yet unconfirmed substrates of Lhs1 and potentially of the Lhs1 homolog in mammals, GRP170.
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Affiliation(s)
- Maria Sukhoplyasova
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Abigail M. Keith
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Emma M. Perrault
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Hannah E. Vorndran
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Alexa S. Jordahl
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Megan E. Yates
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Ashutosh Pastor
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Zachary Li
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Michael L. Freaney
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Riddhi A. Deshpande
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - David B. Adams
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | | | - Shujie Shi
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Thomas R. Kleyman
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, U.S.A
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, U.S.A
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Ossama B. Kashlan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Jeffrey L. Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
| | - Teresa M. Buck
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, U.S.A
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9
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Otero-Sobrino Á, Blanco-Carlón P, Navarro-Aguadero MÁ, Gallardo M, Martínez-López J, Velasco-Estévez M. Mechanosensitive Ion Channels: Their Physiological Importance and Potential Key Role in Cancer. Int J Mol Sci 2023; 24:13710. [PMID: 37762011 PMCID: PMC10530364 DOI: 10.3390/ijms241813710] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/30/2023] [Accepted: 09/01/2023] [Indexed: 09/29/2023] Open
Abstract
Mechanosensitive ion channels comprise a broad group of proteins that sense mechanical extracellular and intracellular changes, translating them into cation influx to adapt and respond to these physical cues. All cells in the organism are mechanosensitive, and these physical cues have proven to have an important role in regulating proliferation, cell fate and differentiation, migration and cellular stress, among other processes. Indeed, the mechanical properties of the extracellular matrix in cancer change drastically due to high cell proliferation and modification of extracellular protein secretion, suggesting an important contribution to tumor cell regulation. In this review, we describe the physiological significance of mechanosensitive ion channels, emphasizing their role in cancer and immunity, and providing compelling proof of the importance of continuing to explore their potential as new therapeutic targets in cancer research.
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Affiliation(s)
- Álvaro Otero-Sobrino
- H12O-CNIO Hematological Malignancies Clinical Research Unit, Centro Nacional de Investigaciones Oncologicas (CNIO), 28029 Madrid, Spain; (Á.O.-S.); (P.B.-C.); (M.Á.N.-A.); (M.G.); (J.M.-L.)
- Department of Hematology, Hospital Universitario 12 de Octubre, Instituto de Investigacion Sanitaria Hospital 12 de Octubre (imas12), 28041 Madrid, Spain
| | - Pablo Blanco-Carlón
- H12O-CNIO Hematological Malignancies Clinical Research Unit, Centro Nacional de Investigaciones Oncologicas (CNIO), 28029 Madrid, Spain; (Á.O.-S.); (P.B.-C.); (M.Á.N.-A.); (M.G.); (J.M.-L.)
- Department of Hematology, Hospital Universitario 12 de Octubre, Instituto de Investigacion Sanitaria Hospital 12 de Octubre (imas12), 28041 Madrid, Spain
| | - Miguel Ángel Navarro-Aguadero
- H12O-CNIO Hematological Malignancies Clinical Research Unit, Centro Nacional de Investigaciones Oncologicas (CNIO), 28029 Madrid, Spain; (Á.O.-S.); (P.B.-C.); (M.Á.N.-A.); (M.G.); (J.M.-L.)
- Department of Hematology, Hospital Universitario 12 de Octubre, Instituto de Investigacion Sanitaria Hospital 12 de Octubre (imas12), 28041 Madrid, Spain
| | - Miguel Gallardo
- H12O-CNIO Hematological Malignancies Clinical Research Unit, Centro Nacional de Investigaciones Oncologicas (CNIO), 28029 Madrid, Spain; (Á.O.-S.); (P.B.-C.); (M.Á.N.-A.); (M.G.); (J.M.-L.)
- Department of Hematology, Hospital Universitario 12 de Octubre, Instituto de Investigacion Sanitaria Hospital 12 de Octubre (imas12), 28041 Madrid, Spain
| | - Joaquín Martínez-López
- H12O-CNIO Hematological Malignancies Clinical Research Unit, Centro Nacional de Investigaciones Oncologicas (CNIO), 28029 Madrid, Spain; (Á.O.-S.); (P.B.-C.); (M.Á.N.-A.); (M.G.); (J.M.-L.)
- Department of Hematology, Hospital Universitario 12 de Octubre, Instituto de Investigacion Sanitaria Hospital 12 de Octubre (imas12), 28041 Madrid, Spain
- Department of Medicine, School of Medicine, Universidad Complutense de Madrid (UCM), 28040 Madrid, Spain
| | - María Velasco-Estévez
- H12O-CNIO Hematological Malignancies Clinical Research Unit, Centro Nacional de Investigaciones Oncologicas (CNIO), 28029 Madrid, Spain; (Á.O.-S.); (P.B.-C.); (M.Á.N.-A.); (M.G.); (J.M.-L.)
- Department of Hematology, Hospital Universitario 12 de Octubre, Instituto de Investigacion Sanitaria Hospital 12 de Octubre (imas12), 28041 Madrid, Spain
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10
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Funes Hernandez M, Bhalla V. Underdiagnosis of Primary Aldosteronism: A Review of Screening and Detection. Am J Kidney Dis 2023; 82:333-346. [PMID: 36965825 DOI: 10.1053/j.ajkd.2023.01.447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 01/08/2023] [Indexed: 03/27/2023]
Abstract
A clinical condition may be missed due to its higher-than-recognized prevalence or inadequate diagnostic screening. Both factors apply to primary aldosteronism, which is woefully underdiagnosed as a cause of hypertension and end-organ damage. Screening tests should be strongly considered for diseases that pose significant morbidity or mortality if left untreated, that have a high prevalence, and that have treatments that lead to improvement or cure. In this review we present the evidence for each of these points. We outline studies that estimate the prevalence of primary aldosteronism in different at-risk populations and how its recognition has changed over time. We also evaluate myriad studies of screening rates for primary aldosteronism and what factors do and do not influence current screening practices. We discuss the ideal conditions for screening, measuring the aldosterone to renin ratio in different populations that use plasma renin activity or direct renin concentration, and the steps for diagnostic workup of primary aldosteronism. Finally, we conclude with potential strategies to implement higher rates of screening and diagnosis of this common, consequential, and treatable disease.
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Affiliation(s)
- Mario Funes Hernandez
- Stanford Hypertension Center and Division of Nephrology, Department of Medicine, School of Medicine, Stanford University, Stanford, California
| | - Vivek Bhalla
- Stanford Hypertension Center and Division of Nephrology, Department of Medicine, School of Medicine, Stanford University, Stanford, California.
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11
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Xu S, Wang F, Mai P, Peng Y, Shu X, Nie R, Zhang H. Mechanism Analysis of Vascular Calcification Based on Fluid Dynamics. Diagnostics (Basel) 2023; 13:2632. [PMID: 37627891 PMCID: PMC10453151 DOI: 10.3390/diagnostics13162632] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 08/05/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Vascular calcification is the abnormal deposition of calcium phosphate complexes in blood vessels, which is regarded as the pathological basis of multiple cardiovascular diseases. The flowing blood exerts a frictional force called shear stress on the vascular wall. Blood vessels have different hydrodynamic properties due to discrepancies in geometric and mechanical properties. The disturbance of the blood flow in the bending area and the branch point of the arterial tree produces a shear stress lower than the physiological magnitude of the laminar shear stress, which can induce the occurrence of vascular calcification. Endothelial cells sense the fluid dynamics of blood and transmit electrical and chemical signals to the full-thickness of blood vessels. Through crosstalk with endothelial cells, smooth muscle cells trigger osteogenic transformation, involved in mediating vascular intima and media calcification. In addition, based on the detection of fluid dynamics parameters, emerging imaging technologies such as 4D Flow MRI and computational fluid dynamics have greatly improved the early diagnosis ability of cardiovascular diseases, showing extremely high clinical application prospects.
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Affiliation(s)
- Shuwan Xu
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
| | - Feng Wang
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
| | - Peibiao Mai
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
| | - Yanren Peng
- Department of Cardiology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou 510120, China; (Y.P.); (X.S.)
| | - Xiaorong Shu
- Department of Cardiology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou 510120, China; (Y.P.); (X.S.)
| | - Ruqiong Nie
- Department of Cardiology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou 510120, China; (Y.P.); (X.S.)
| | - Huanji Zhang
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
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12
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Olde Hanhof CJA, Dilmen E, Yousef Yengej FA, Latta F, Ammerlaan CME, Schreurs J, Hooijmaijers L, Jansen J, Rookmaaker MB, Orhon I, Verhaar MC, Hoenderop JG. Differentiated mouse kidney tubuloids as a novel in vitro model to study collecting duct physiology. Front Cell Dev Biol 2023; 11:1086823. [PMID: 36760360 PMCID: PMC9905633 DOI: 10.3389/fcell.2023.1086823] [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: 11/01/2022] [Accepted: 01/06/2023] [Indexed: 01/26/2023] Open
Abstract
Kidney tubuloids are cell models that are derived from human or mouse renal epithelial cells and show high similarities with their in vivo counterparts. Tubuloids grow polarized in 3D, allow for long-term expansion, and represent multiple segments of the nephron, as shown by their gene expression pattern. In addition, human tubuloids form tight, functional barriers and have been succesfully used for drug testing. Our knowledge of mouse tubuloids, on the other hand, is only minimal. In this study, we further characterized mouse tubuloids and differentiated them towards the collecting duct, which led to a significant upregulation of collecting duct-specific mRNAs of genes and protein expression, including the water channel AQP2 and the sodium channel ENaC. Differentiation resulted in polarized expression of collecting duct water channels AQP2 and AQP3. Also, a physiological response to desmopressin and forskolin stimulation by translocation of AQP2 to the apical membrane was demonstrated. Furthermore, amiloride-sensitive ENaC-mediated sodium uptake was shown in differentiated tubuloids using radioactive tracer sodium. This study demonstrates that mouse tubuloids can be differentiated towards the collecting duct and exhibit collecting duct-specific function. This illustrates the potential use of mouse kidney tubuloids as novel in vitro models to study (patho)physiology of kidney diseases.
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Affiliation(s)
- C. J. A. Olde Hanhof
- Department of Molecular Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - E. Dilmen
- Department of Molecular Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - F. A. Yousef Yengej
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands,Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, Netherlands
| | - F. Latta
- Department of Molecular Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - C. M. E. Ammerlaan
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands,Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, Netherlands
| | - J. Schreurs
- Department of Molecular Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - L. Hooijmaijers
- Department of Molecular Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - J. Jansen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands,Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Amalia Children’s Hospital, Nijmegen, Netherlands,Institute of Experimental Medicine and Systems Biology, Medical Faculty RWTH Aachen University, Aachen, Germany
| | - M. B. Rookmaaker
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, Netherlands
| | - I. Orhon
- Department of Molecular Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - M. C. Verhaar
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, Netherlands
| | - J. G. Hoenderop
- Department of Molecular Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands,*Correspondence: J. G. Hoenderop,
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13
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Modus operandi of ClC-K2 Cl - Channel in the Collecting Duct Intercalated Cells. Biomolecules 2023; 13:biom13010177. [PMID: 36671562 PMCID: PMC9855527 DOI: 10.3390/biom13010177] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
The renal collecting duct is known to play a critical role in many physiological processes, including systemic water-electrolyte homeostasis, acid-base balance, and the salt sensitivity of blood pressure. ClC-K2 (ClC-Kb in humans) is a Cl--permeable channel expressed on the basolateral membrane of several segments of the renal tubule, including the collecting duct intercalated cells. ClC-Kb mutations are causative for Bartters' syndrome type 3 manifested as hypotension, urinary salt wasting, and metabolic alkalosis. However, little is known about the significance of the channel in the collecting duct with respect to the normal physiology and pathology of Bartters' syndrome. In this review, we summarize the available experimental evidence about the signaling determinants of ClC-K2 function and the regulation by systemic and local factors as well as critically discuss the recent advances in understanding the collecting-duct-specific roles of ClC-K2 in adaptations to changes in dietary Cl- intake and maintaining systemic acid-base homeostasis.
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14
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Jang H, Park Y, Jang J. Serum and glucocorticoid-regulated kinase 1: Structure, biological functions, and its inhibitors. Front Pharmacol 2022; 13:1036844. [PMID: 36457711 PMCID: PMC9706101 DOI: 10.3389/fphar.2022.1036844] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 10/20/2022] [Indexed: 08/11/2023] Open
Abstract
Serum and glucocorticoid-regulated kinase 1 (SGK1) is a serine/threonine kinase belonging to the protein kinase A, G, and C (AGC) family. Upon initiation of the phosphoinositide 3-kinase (PI3K) signaling pathway, mammalian target of rapamycin complex 2 (mTORC2) and phosphoinositide-dependent protein kinase 1 (PDK1) phosphorylate the hydrophobic motif and kinase domain of SGK1, respectively, inducing SGK1 activation. SGK1 modulates essential cellular processes such as proliferation, survival, and apoptosis. Hence, dysregulated SGK1 expression can result in multiple diseases, including hypertension, cancer, autoimmunity, and neurodegenerative disorders. This review provides a current understanding of SGK1, particularly in sodium transport, cancer progression, and autoimmunity. In addition, we summarize the developmental status of SGK1 inhibitors, their structures, and respective potencies evaluated in pre-clinical experimental settings. Collectively, this review highlights the significance of SGK1 and proposes SGK1 inhibitors as potential drugs for treatment of clinically relevant diseases.
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Affiliation(s)
- Hyunsoo Jang
- College of Pharmacy, Korea University, Sejong, South Korea
| | - Youngjun Park
- Laboratory of Immune and Inflammatory Disease, College of Pharmacy, Jeju Research Institute of Pharmaceutical Sciences, Jeju National University, Jeju, South Korea
- Interdisciplinary Graduate Program in Advanced Convergence Technology and Science, Jeju National University, Jeju, South Korea
| | - Jaebong Jang
- College of Pharmacy, Korea University, Sejong, South Korea
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15
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Cao N, Lan C, Chen C, Xu Z, Luo H, Zheng S, Gong X, Ren H, Li Z, Qu S, Yu C, Yang J, Jose PA, Chen Y, Wu G, Hu C, Yu J, Zeng C. Prenatal Lipopolysaccharides Exposure Induces Transgenerational Inheritance of Hypertension. Circulation 2022; 146:1082-1095. [PMID: 36004643 PMCID: PMC9529859 DOI: 10.1161/circulationaha.122.059891] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 07/26/2022] [Indexed: 01/24/2023]
Abstract
BACKGROUND Adverse environmental exposure during the prenatal period can lead to diseases in the offspring, including hypertension. Whether or not the hypertensive phenotype can be transgenerationally transmitted is not known. METHODS Pregnant Sprague Dawley rats were intraperitoneally injected with lipopolysaccharide (LPS) on gestation days 6, 8, 10, and 12 to generate the prenatal LPS exposure model. Blood pressure was monitored by both telemetry and tail-cuff method. RNA sequencing was performed to analyze transcriptome alteration in the kidney of the third generation. Tempol and spironolactone were used to test the potential preventative and therapeutic effect of targeting reactive oxygen species and mineralocorticoid receptor signaling, respectively. Molecular biological experiments were performed to illustrate the mechanism of epigenetic and transcription regulation. RESULTS Prenatal LPS exposure can impair the ability to excrete a salt load and induce hypertension from the first to the third generations, with the fourth and fifth generations, inducing salt-sensitive hypertension. Compared with control pups, the transcriptome in the kidney of the hypertensive third-generation prenatal LPS-exposed offspring have upregulation of the Ras-related C3 botulinum toxin substrate 1 (Rac1) gene and activation of mineralocorticoid receptor signaling. Furthermore, we found that LPS exposure during pregnancy triggered oxidative stress that upregulated KDM3B (histone lysine demethylase 3B) in the oocytes of first-generation female rats, leading to an inheritable low level of H3K9me2 (histone H3 lysine 9 dimethylation), resulting in the transgenerational upregulation of Rac1. Based on these findings, we treated the LPS-exposed pregnant rats with the reactive oxygen species scavenger, tempol, which successfully prevented hypertension in the first-generation offspring and the transgenerational inheritance of hypertension. CONCLUSIONS These findings show that adverse prenatal exposure induces transgenerational hypertension through an epigenetic-regulated mechanism and identify potentially preventive and therapeutic strategies for hypertension.
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Affiliation(s)
- Nian Cao
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
- Department of Cardiology, the Sixth Medical Centre, Chinese PLA General Hospital, Beijing, P.R. China
| | - Cong Lan
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Caiyu Chen
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Zaicheng Xu
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Hao Luo
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Shuo Zheng
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Xue Gong
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
- Department of Cardiology, the Sixth Medical Centre, Chinese PLA General Hospital, Beijing, P.R. China
| | - Hongmei Ren
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Zhuxin Li
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Shuang Qu
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Cheng Yu
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Jining Yang
- Research Center for Nutrition and Food Safety, Chongqing Key Laboratory of Nutrition and Food Safety, Institute of Military Preventive Medicine, The Third Military Medical University, Chongqing, P.R. China
| | - Pedro A. Jose
- Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Yundai Chen
- Department of Cardiology, the Sixth Medical Centre, Chinese PLA General Hospital, Beijing, P.R. China
| | - Gengze Wu
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Cuimei Hu
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Junyi Yu
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, P. R. China
- State Key Laboratory of Trauma, Burns and Combined Injury, Daping Hospital, The Third Military Medical University, Chongqing, P. R. China
- Heart Center of Fujian Province, Union Hospital, Fujian Medical University, Fuzhou, P.R. China
- Department of Cardiology, Chongqing General Hospital, Chongqing, P. R. China
- Cardiovascular Research Center of Chongqing College, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Chongqing, P. R. China
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16
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Yang T, Song C, Ralph DL, Andrews P, Sparks MA, Koller BH, McDonough AA, Coffman TM. Cell-Specific Actions of the Prostaglandin E-Prostanoid Receptor 4 Attenuating Hypertension: A Dominant Role for Kidney Epithelial Cells Compared With Macrophages. J Am Heart Assoc 2022; 11:e026581. [PMID: 36172956 PMCID: PMC9673718 DOI: 10.1161/jaha.122.026581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Background A beneficial role for prostanoids in hypertension is suggested by clinical studies showing nonsteroidal anti-inflammatory drugs, which block the production of all prostanoids, cause sodium retention and exacerbate hypertension. Among prostanoids, prostaglandin E2 and its E-prostanoid receptor 4 receptor (EP4R) have been implicated in blood pressure control. Our previous study found that conditional deletion of EP4R from all tissues in adult mice exacerbates angiotensin II-dependent hypertension, suggesting a powerful effect of EP4R to resist blood pressure elevation. We also found that elimination of EP4R from vascular smooth muscle cells did not affect the severity of hypertension, suggesting nonvascular targets of prostaglandin E mediate this antihypertensive effect. Methods and Results Here we generated mice with cell-specific deletion of EP4R from macrophage-specific EP4 receptor knockouts or kidney epithelial cells (KEKO) to assess the contributions of EP4R in these cells to hypertension pathogenesis. Macrophage-specific EP4 receptor knockouts showed similar blood pressure responses to alterations in dietary sodium or chronic angiotensin II infusion as Controls. By contrast, angiotensin II-dependent hypertension was significantly augmented in KEKOs (mean arterial pressure: 146±3 mm Hg) compared with Controls (137±4 mm Hg; P=0.02), which was accompanied by impaired natriuresis in KEKOs. Because EP4R expression in the kidney is enriched in the collecting duct, we compared responses to amiloride in angiotensin II-infused KEKOs and Controls. Blockade of the epithelial sodium channel with amiloride caused exaggerated natriuresis in KEKOs compared with Controls (0.21±0.01 versus 0.15±0.02 mmol/24 hour per 20 g; P=0.015). Conclusions Our data suggest EP4R in kidney epithelia attenuates hypertension. This antihypertension effect of EP4R may be mediated by reducing the activity of the epithelial sodium channel, thereby promoting natriuresis.
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Affiliation(s)
- Ting Yang
- Division of Nephrology‐Department of MedicineDuke UniversityDurhamNC
| | - Chengcheng Song
- Division of Nephrology‐Department of MedicineDuke UniversityDurhamNC,Department of AnesthesiologyTianjin Medical University General HospitalTianjinChina
| | - Donna L. Ralph
- Department of Physiology and NeuroscienceKeck School of Medicine of the University of Southern CaliforniaLos AngelesCA
| | - Portia Andrews
- Division of Nephrology‐Department of MedicineDuke UniversityDurhamNC
| | - Matthew A. Sparks
- Division of Nephrology‐Department of MedicineDuke UniversityDurhamNC
| | | | - Alicia A. McDonough
- Department of Physiology and NeuroscienceKeck School of Medicine of the University of Southern CaliforniaLos AngelesCA
| | - Thomas M. Coffman
- Division of Nephrology‐Department of MedicineDuke UniversityDurhamNC,Cardiovascular and Metabolic Disorders Research ProgramDuke‐National University of Singapore Graduate Medical SchoolSingapore
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17
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Mutengo KH, Masenga SK, Mwesigwa N, Patel KP, Kirabo A. Hypertension and human immunodeficiency virus: A paradigm for epithelial sodium channels? Front Cardiovasc Med 2022; 9:968184. [PMID: 36093171 PMCID: PMC9452753 DOI: 10.3389/fcvm.2022.968184] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 08/10/2022] [Indexed: 02/03/2023] Open
Abstract
Hypertension is a risk factor for end organ damage and death and is more common in persons with HIV compared to the general population. Several mechanisms have been studied in the pathogenesis of hypertension. Current evidence suggests that the epithelial sodium channel (ENaC) plays a key role in regulating blood pressure through the transport of sodium and water across membranes in the kidney tubules, resulting in retention of sodium and water and an altered fluid balance. However, there is scarcity of information that elucidates the role of ENaC in HIV as it relates to increasing the risk for development or pathogenesis of hypertension. This review summarized the evidence to date implicating a potential role for altered ENaC activity in contributing to hypertension in patients with HIV.
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Affiliation(s)
- Katongo H. Mutengo
- School of Medicine and Health Sciences, HAND Research Group, Mulungushi University, Livingstone Campus, Livingstone, Zambia,School of Public Health and Medicine, University of Zambia, Lusaka, Zambia
| | - Sepiso K. Masenga
- School of Medicine and Health Sciences, HAND Research Group, Mulungushi University, Livingstone Campus, Livingstone, Zambia,School of Public Health and Medicine, University of Zambia, Lusaka, Zambia
| | - Naome Mwesigwa
- Department of Medicine and Dentistry, Kampala International University, Kampala, Uganda
| | - Kaushik P. Patel
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Annet Kirabo
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States,*Correspondence: Annet Kirabo,
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18
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Su M, Liu N, Zhang Z, Zhang J. Osmoregulatory strategies of estuarine fish Scatophagus argus in response to environmental salinity changes. BMC Genomics 2022; 23:545. [PMID: 35907798 PMCID: PMC9339187 DOI: 10.1186/s12864-022-08784-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 07/20/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Scatophagus argus, an estuarine inhabitant, can rapidly adapt to different salinity environments. However, the knowledge of the molecular mechanisms underlying its strong salinity tolerance remains unclear. The gill, as the main osmoregulatory organ, plays a vital role in the salinity adaptation of the fish, and thus relative studies are constructive to reveal unique osmoregulatory mechanisms in S. argus. RESULTS In the present study, iTRAQ coupled with nanoLC-MS/MS techniques were employed to explore branchial osmoregulatory mechanisms in S. argus acclimated to different salinities. Among 1,604 identified proteins, 796 differentially expressed proteins (DEPs) were detected. To further assess osmoregulatory strategies in the gills under different salinities, DEPs related to osmoregulatory (22), non-directional (18), hypo- (52), and hypersaline (40) stress responses were selected. Functional annotation analysis of these selected DEPs indicated that the cellular ion regulation (e.g. Na+-K+-ATPase [NKA] and Na+-K+-2Cl- cotransporter 1 [NKCC1]) and ATP synthesis were deeply involved in the osmoregulatory process. As an osmoregulatory protein, NKCC1 expression was inhibited under hyposaline stress but showed the opposite trend in hypersaline conditions. The expression levels of NKA α1 and β1 were only increased under hypersaline challenge. However, hyposaline treatments could enhance branchial NKA activity, which was inhibited under hypersaline environments, and correspondingly, reduced ATP content was observed in gill tissues exposed to hyposaline conditions, while its contents were increased in hypersaline groups. In vitro experiments indicated that Na+, K+, and Cl- ions were pumped out of branchial cells under hypoosmotic stress, whereas they were absorbed into cells under hyperosmotic conditions. Based on our results, we speculated that NKCC1-mediated Na+ influx was inhibited, and proper Na+ efflux was maintained by improving NKA activity under hyposaline stress, promoting the rapid adaptation of branchial cells to the hyposaline condition. Meanwhile, branchial cells prevented excessive loss of ions by increasing NKA internalization and reducing ATP synthesis. In contrast, excess ions in cells exposed to the hyperosmotic medium were excreted with sufficient energy supply, and reduced NKA activity and enhanced NKCC1-mediated Na+ influx were considered a compensatory regulation. CONCLUSIONS S. argus exhibited divergent osmoregulatory strategies in the gills when encountering hypoosmotic and hyperosmotic stresses, facilitating effective adaptabilities to a wide range of environmental salinity fluctuation.
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Affiliation(s)
- Maoliang Su
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518060, China
| | - Nanxi Liu
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518060, China
| | - Zhengqi Zhang
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518060, China
| | - Junbin Zhang
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518060, China.
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19
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Mernea M, Ulăreanu RȘ, Cucu D, Al-Saedi JH, Pop CE, Fendrihan S, Anghelescu GDC, Mihăilescu DF. Epithelial Sodium Channel Inhibition by Amiloride Addressed with THz Spectroscopy and Molecular Modeling. Molecules 2022; 27:3271. [PMID: 35630748 PMCID: PMC9144217 DOI: 10.3390/molecules27103271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/08/2022] [Accepted: 05/18/2022] [Indexed: 11/16/2022] Open
Abstract
THz spectroscopy is important for the study of ion channels because it directly addresses the low frequency collective motions relevant for their function. Here we used THz spectroscopy to investigate the inhibition of the epithelial sodium channel (ENaC) by its specific blocker, amiloride. Experiments were performed on A6 cells' suspensions, which are cells overexpressing ENaC derived from Xenopus laevis kidney. THz spectra were investigated with or without amiloride. When ENaC was inhibited by amiloride, a substantial increase in THz absorption was noticed. Molecular modeling methods were used to explain the observed spectroscopic differences. THz spectra were simulated using the structural models of ENaC and ENaC-amiloride complexes built here. The agreement between the experiment and the simulations allowed us to validate the structural models and to describe the amiloride dynamics inside the channel pore. The amiloride binding site validated using THz spectroscopy agrees with previous mutagenesis studies. Altogether, our results show that THz spectroscopy can be successfully used to discriminate between native and inhibited ENaC channels and to characterize the dynamics of channels in the presence of their specific antagonist.
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Affiliation(s)
- Maria Mernea
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței Str., 050095 Bucharest, Romania; (M.M.); (R.Ș.U.); (J.H.A.-S.); (G.D.C.A.); (D.F.M.)
| | - Roxana Ștefania Ulăreanu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței Str., 050095 Bucharest, Romania; (M.M.); (R.Ș.U.); (J.H.A.-S.); (G.D.C.A.); (D.F.M.)
| | - Dana Cucu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței Str., 050095 Bucharest, Romania; (M.M.); (R.Ș.U.); (J.H.A.-S.); (G.D.C.A.); (D.F.M.)
| | - Jasim Hafedh Al-Saedi
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței Str., 050095 Bucharest, Romania; (M.M.); (R.Ș.U.); (J.H.A.-S.); (G.D.C.A.); (D.F.M.)
| | - Cristian-Emilian Pop
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței Str., 050095 Bucharest, Romania;
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania;
| | - Sergiu Fendrihan
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania;
- Faculty of Medicine, University “Vasile Goldis”, Bulevardul Revoluției 94, 310025 Arad, Romania
| | - Giorgiana Diana Carmen Anghelescu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței Str., 050095 Bucharest, Romania; (M.M.); (R.Ș.U.); (J.H.A.-S.); (G.D.C.A.); (D.F.M.)
| | - Dan Florin Mihăilescu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței Str., 050095 Bucharest, Romania; (M.M.); (R.Ș.U.); (J.H.A.-S.); (G.D.C.A.); (D.F.M.)
- Biometric Psychiatric Genetics Research Unit, Alexandru Obregia Psychiatric Hospital, 10 Șoseaua Berceni Str., 041914 Bucharest, Romania
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20
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Blaconà G, Raso R, Castellani S, Pierandrei S, Del Porto P, Ferraguti G, Ascenzioni F, Conese M, Lucarelli M. Downregulation of epithelial sodium channel (ENaC) activity in cystic fibrosis cells by epigenetic targeting. Cell Mol Life Sci 2022; 79:257. [PMID: 35462606 PMCID: PMC9035428 DOI: 10.1007/s00018-022-04190-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/28/2022] [Accepted: 02/02/2022] [Indexed: 12/31/2022]
Abstract
The pathogenic mechanism of cystic fibrosis (CF) includes the functional interaction of the cystic fibrosis transmembrane conductance regulator (CFTR) protein with the epithelial sodium channel (ENaC). The reduction of ENaC activity may constitute a therapeutic option for CF. This hypothesis was evaluated using drugs that target the protease-dependent activation of the ENaC channel and the transcriptional activity of its coding genes. To this aim we used: camostat, a protease inhibitor; S-adenosyl methionine (SAM), showed to induce DNA hypermethylation; curcumin, known to produce chromatin condensation. SAM and camostat are drugs already clinically used in other pathologies, while curcumin is a common dietary compound. The experimental systems used were CF and non-CF immortalized human bronchial epithelial cell lines as well as human bronchial primary epithelial cells. ENaC activity and SCNN1A, SCNN1B and SCNN1G gene expression were analyzed, in addition to SCNN1B promoter methylation. In both immortalized and primary cells, the inhibition of extracellular peptidases and the epigenetic manipulations reduced ENaC activity. Notably, the reduction in primary cells was much more effective. The SCNN1B appeared to be the best target to reduce ENaC activity, in respect to SCNN1A and SCNN1G. Indeed, SAM treatment resulted to be effective in inducing hypermethylation of SCNN1B gene promoter and in lowering its expression. Importantly, CFTR expression was unaffected, or even upregulated, after treatments. These results open the possibility of CF patients’ treatment by epigenetic targeting.
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Affiliation(s)
- Giovanna Blaconà
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Roberto Raso
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Stefano Castellani
- Department of Biomedical Sciences and Human Oncology, University of Bari, Bari, Italy
| | - Silvia Pierandrei
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Paola Del Porto
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Giampiero Ferraguti
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Fiorentina Ascenzioni
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Massimo Conese
- Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy.
| | - Marco Lucarelli
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy. .,Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University of Rome, Rome, Italy.
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21
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Douma LG, Costello HM, Crislip GR, Cheng KY, Lynch IJ, Juffre A, Barral D, Masten S, Roig E, Beguiristain K, Li W, Bratanatawira P, Wingo CS, Gumz ML. Kidney-specific KO of the circadian clock protein PER1 alters renal Na + handling, aldosterone levels, and kidney/adrenal gene expression. Am J Physiol Renal Physiol 2022; 322:F449-F459. [PMID: 35129370 PMCID: PMC9169971 DOI: 10.1152/ajprenal.00385.2021] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 01/20/2022] [Accepted: 01/28/2022] [Indexed: 11/22/2022] Open
Abstract
PERIOD 1 (PER1) is a circadian clock transcription factor that is regulated by aldosterone, a hormone that increases blood volume and Na+ retention to increase blood pressure. Male global Per1 knockout (KO) mice develop reduced night/day differences in Na+ excretion in response to a high-salt diet plus desoxycorticosterone pivalate treatment (HS + DOCP), a model of salt-sensitive hypertension. In addition, global Per1 KO mice exhibit higher aldosterone levels on a normal-salt diet. To determine the role of Per1 in the kidney, male kidney-specific Per1 KO (KS-Per1 KO) mice were generated using Ksp-cadherin Cre recombinase to remove exons 2-8 of Per1 in the distal nephron and collecting duct. Male KS-Per1 KO mice have increased Na+ retention but have normal diurnal differences in Na+ excretion in response to HS + DOCP. The increased Na+ retention is associated with altered expression of glucocorticoid and mineralocorticoid receptors, increased serum aldosterone, and increased medullary endothelin-1 compared with control mice. Adrenal gland gene expression analysis revealed that circadian clock and aldosterone synthesis genes have altered expression in KS-Per1 KO mice compared with control mice. These results emphasize the importance of the circadian clock not only in maintaining rhythms of physiological functions but also for adaptability in response to environmental cues, such as HS + DOCP, to maintain overall homeostasis. Given the prevalence of salt-sensitive hypertension in the general population, these findings have important implications for our understanding of how circadian clock proteins regulate homeostasis.NEW & NOTEWORTHY For the first time, we show that knockout of the circadian clock transcription factor PERIOD 1 using kidney-specific cadherin Cre results in increased renal Na+ reabsorption, increased aldosterone levels, and changes in gene expression in both the kidney and adrenal gland. Diurnal changes in renal Na+ excretion were not observed, demonstrating that the clock protein PER1 in the kidney is important for maintaining homeostasis and that this effect may be independent of time of day.
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Affiliation(s)
- Lauren G Douma
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida
| | - Hannah M Costello
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - G Ryan Crislip
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - Kit-Yan Cheng
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - I Jeanette Lynch
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
- North Florida/South Georgia Malcolm Randall Veterans Affairs Medical Center, Gainesville, Florida
| | - Alexandria Juffre
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida
| | - Dominique Barral
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - Sarah Masten
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - Emilio Roig
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - Kevin Beguiristain
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - Wendy Li
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - Phillip Bratanatawira
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
| | - Charles S Wingo
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
- North Florida/South Georgia Malcolm Randall Veterans Affairs Medical Center, Gainesville, Florida
| | - Michelle L Gumz
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
- Division of Nephrology, Hypertension, and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida
- Center for Integrative Cardiovascular and Metabolic Diseases, University of Florida, Gainesville, Florida
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22
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Abd El-Aziz TM, Kaur A, Shapiro MS, Stockand JD, Archer CR. Optogenetic Control of PIP2 Interactions Shaping ENaC Activity. Int J Mol Sci 2022; 23:ijms23073884. [PMID: 35409240 PMCID: PMC8998630 DOI: 10.3390/ijms23073884] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 03/29/2022] [Indexed: 02/06/2023] Open
Abstract
The activity of the epithelial Na+ Channel (ENaC) is strongly dependent on the membrane phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2). PIP2 binds two distinct cationic clusters within the N termini of β- and γ-ENaC subunits (βN1 and γN2). The affinities of these sites were previously determined using short synthetic peptides, yet their role in sensitizing ENaC to changes in PIP2 levels in the cellular system is not well established. We addressed this question by comparing the effects of PIP2 depletion and recovery on ENaC channel activity and intracellular Na+ levels [Na+]i. We tested effects on ENaC activity with mutations to the PIP2 binding sites using the optogenetic system CIBN/CRY2-OCRL to selectively deplete PIP2. We monitored changes of [Na+]i by measuring the fluorescent Na+ indicator, CoroNa Green AM, and changes in channel activity by performing patch clamp electrophysiology. Whole cell patch clamp measurements showed a complete lack of response to PIP2 depletion and recovery in ENaC with mutations to βN1 or γN2 or both sites, compared to wild type ENaC. Whereas mutant βN1 also had no change in CoroNa Green fluorescence in response to PIP2 depletion, γN2 did have reduced [Na+]i, which was explained by having shorter CoroNa Green uptake and half-life. These results suggest that CoroNa Green measurements should be interpreted with caution. Importantly, the electrophysiology results show that the βN1 and γN2 sites on ENaC are each necessary to permit maximal ENaC activity in the presence of PIP2.
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Affiliation(s)
- Tarek Mohamed Abd El-Aziz
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78228, USA; (T.M.A.E.-A.); (M.S.S.); (J.D.S.)
- Faculty of Science, Zoology Department, Minia University, El-Minia 61519, Egypt
| | - Amanpreet Kaur
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA;
| | - Mark S. Shapiro
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78228, USA; (T.M.A.E.-A.); (M.S.S.); (J.D.S.)
| | - James D. Stockand
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78228, USA; (T.M.A.E.-A.); (M.S.S.); (J.D.S.)
| | - Crystal R. Archer
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78228, USA; (T.M.A.E.-A.); (M.S.S.); (J.D.S.)
- Correspondence:
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23
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Role of Ion Channel Remodeling in Endothelial Dysfunction Induced by Pulmonary Arterial Hypertension. Biomolecules 2022; 12:biom12040484. [PMID: 35454073 PMCID: PMC9031742 DOI: 10.3390/biom12040484] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 12/12/2022] Open
Abstract
Endothelial dysfunction is a key player in advancing vascular pathology in pulmonary arterial hypertension (PAH), a disease essentially characterized by intense remodeling of the pulmonary vasculature, vasoconstriction, endothelial dysfunction, inflammation, oxidative stress, and thrombosis in situ. These vascular features culminate in an increase in pulmonary vascular resistance, subsequent right heart failure, and premature death. Over the past years, there has been a great development in our understanding of pulmonary endothelial biology related to the genetic and molecular mechanisms that modulate the endothelial response to direct or indirect injury and how their dysregulation can promote PAH pathogenesis. Ion channels are key regulators of vasoconstriction and proliferative/apoptotic phenotypes; however, they are poorly studied at the endothelial level. The current review will describe and categorize different expression, functions, regulation, and remodeling of endothelial ion channels (K+, Ca2+, Na+, and Cl− channels) in PAH. We will focus on the potential pathogenic role of ion channel deregulation in the onset and progression of endothelial dysfunction during the development of PAH and its potential therapeutic role.
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24
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Joshi R, Pohl P, Strachotova D, Herman P, Obsil T, Obsilova V. Nedd4-2 binding to 14-3-3 modulates the accessibility of its catalytic site and WW domains. Biophys J 2022; 121:1299-1311. [PMID: 35189105 PMCID: PMC9034186 DOI: 10.1016/j.bpj.2022.02.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/30/2021] [Accepted: 02/15/2022] [Indexed: 11/02/2022] Open
Abstract
Neural precursor cells expressed developmentally downregulated protein 4-2 (Nedd4-2), a homologous to the E6-AP carboxyl terminus (HECT) ubiquitin ligase, triggers the endocytosis and degradation of its downstream target molecules by regulating signal transduction through interactions with other targets, including 14-3-3 proteins. In our previous study, we found that 14-3-3 binding induces a structural rearrangement of Nedd4-2 by inhibiting interactions between its structured domains. Here, we used time-resolved fluorescence intensity and anisotropy decay measurements, together with fluorescence quenching and mass spectrometry, to further characterize interactions between Nedd4-2 and 14-3-3 proteins. The results showed that 14-3-3 binding affects the emission properties of AEDANS-labeled WW3, WW4, and, to a lesser extent, WW2 domains, and reduces their mobility, but not those of the WW1 domain, which remains mobile. In contrast, 14-3-3 binding has the opposite effect on the active site of the HECT domain, which is more solvent exposed and mobile in the complexed form than in the apo form of Nedd4-2. Overall, our results suggest that steric hindrance of the WW3 and WW4 domains combined with conformational changes in the catalytic domain may account for the 14-3-3 binding-mediated regulation of Nedd4-2.
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25
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Brandt MM, Cheng C, Merkus D, Duncker DJ, Sorop O. Mechanobiology of Microvascular Function and Structure in Health and Disease: Focus on the Coronary Circulation. Front Physiol 2022; 12:771960. [PMID: 35002759 PMCID: PMC8733629 DOI: 10.3389/fphys.2021.771960] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/11/2021] [Indexed: 12/19/2022] Open
Abstract
The coronary microvasculature plays a key role in regulating the tight coupling between myocardial perfusion and myocardial oxygen demand across a wide range of cardiac activity. Short-term regulation of coronary blood flow in response to metabolic stimuli is achieved via adjustment of vascular diameter in different segments of the microvasculature in conjunction with mechanical forces eliciting myogenic and flow-mediated vasodilation. In contrast, chronic adjustments in flow regulation also involve microvascular structural modifications, termed remodeling. Vascular remodeling encompasses changes in microvascular diameter and/or density being largely modulated by mechanical forces acting on the endothelium and vascular smooth muscle cells. Whereas in recent years, substantial knowledge has been gathered regarding the molecular mechanisms controlling microvascular tone and how these are altered in various diseases, the structural adaptations in response to pathologic situations are less well understood. In this article, we review the factors involved in coronary microvascular functional and structural alterations in obstructive and non-obstructive coronary artery disease and the molecular mechanisms involved therein with a focus on mechanobiology. Cardiovascular risk factors including metabolic dysregulation, hypercholesterolemia, hypertension and aging have been shown to induce microvascular (endothelial) dysfunction and vascular remodeling. Additionally, alterations in biomechanical forces produced by a coronary artery stenosis are associated with microvascular functional and structural alterations. Future studies should be directed at further unraveling the mechanisms underlying the coronary microvascular functional and structural alterations in disease; a deeper understanding of these mechanisms is critical for the identification of potential new targets for the treatment of ischemic heart disease.
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Affiliation(s)
- Maarten M Brandt
- Division of Experimental Cardiology, Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Caroline Cheng
- Division of Experimental Cardiology, Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands.,Division of Internal Medicine and Dermatology, Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, Netherlands
| | - Daphne Merkus
- Division of Experimental Cardiology, Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands.,Walter Brendel Center of Experimental Medicine (WBex), LMU Munich, Munich, Germany.,German Center for Cardiovascular Research (DZHK), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany
| | - Dirk J Duncker
- Division of Experimental Cardiology, Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Oana Sorop
- Division of Experimental Cardiology, Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
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26
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Xia S, Bozóky Z, Di Paola M, Laselva O, Ahmadi S, Jiang JX, Pitstick AL, Jiang C, Rotin D, Mayhew CN, Jones NL, Bear CE. High-Throughput Functional Analysis of CFTR and Other Apically Localized Proteins in iPSC-Derived Human Intestinal Organoids. Cells 2021; 10:cells10123419. [PMID: 34943927 PMCID: PMC8699884 DOI: 10.3390/cells10123419] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/26/2021] [Accepted: 11/30/2021] [Indexed: 01/15/2023] Open
Abstract
Induced Pluripotent Stem Cells (iPSCs) can be differentiated into epithelial organoids that recapitulate the relevant context for CFTR and enable testing of therapies targeting Cystic Fibrosis (CF)-causing mutant proteins. However, to date, CF-iPSC-derived organoids have only been used to study pharmacological modulation of mutant CFTR channel activity and not the activity of other disease-relevant membrane protein constituents. In the current work, we describe a high-throughput, fluorescence-based assay of CFTR channel activity in iPSC-derived intestinal organoids and describe how this method can be adapted to study other apical membrane proteins. Specifically, we show how this assay can be employed to study CFTR and ENaC channels and an electrogenic acid transporter in the same iPSC-derived intestinal tissue. This phenotypic platform promises to expand CF therapy discovery to include strategies that target multiple determinants of epithelial fluid transport.
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Affiliation(s)
- Sunny Xia
- Molecular Medicine, Hospital for Sick Children, 686 Bay St, Toronto, ON M5G 0A4, Canada; (S.X.); (Z.B.); (O.L.); (J.X.J.)
- Cell Biology, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; (C.J.); (D.R.); (N.L.J.)
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada;
| | - Zoltán Bozóky
- Molecular Medicine, Hospital for Sick Children, 686 Bay St, Toronto, ON M5G 0A4, Canada; (S.X.); (Z.B.); (O.L.); (J.X.J.)
| | - Michelle Di Paola
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada;
| | - Onofrio Laselva
- Molecular Medicine, Hospital for Sick Children, 686 Bay St, Toronto, ON M5G 0A4, Canada; (S.X.); (Z.B.); (O.L.); (J.X.J.)
- Department of Medical and Surgical Sciences, University of Foggia, 71122 Foggia, Italy
| | - Saumel Ahmadi
- Department of Neurology, Washington University in St. Louis, St. Louis, MO 63110, USA;
| | - Jia Xin Jiang
- Molecular Medicine, Hospital for Sick Children, 686 Bay St, Toronto, ON M5G 0A4, Canada; (S.X.); (Z.B.); (O.L.); (J.X.J.)
| | - Amy L. Pitstick
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA; (A.L.P.); (C.N.M.)
| | - Chong Jiang
- Cell Biology, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; (C.J.); (D.R.); (N.L.J.)
| | - Daniela Rotin
- Cell Biology, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; (C.J.); (D.R.); (N.L.J.)
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Christopher N. Mayhew
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA; (A.L.P.); (C.N.M.)
| | - Nicola L. Jones
- Cell Biology, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; (C.J.); (D.R.); (N.L.J.)
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada;
- Department of Paediatrics, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Christine E. Bear
- Molecular Medicine, Hospital for Sick Children, 686 Bay St, Toronto, ON M5G 0A4, Canada; (S.X.); (Z.B.); (O.L.); (J.X.J.)
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada;
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 0A4, Canada
- Correspondence:
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27
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D'Urso O, Drago F. Pharmacological significance of extra-oral taste receptors. Eur J Pharmacol 2021; 910:174480. [PMID: 34496302 DOI: 10.1016/j.ejphar.2021.174480] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 08/23/2021] [Accepted: 09/01/2021] [Indexed: 01/17/2023]
Abstract
It has recently been shown that taste receptors, in addition to being present in the oral cavity, exist in various extra-oral organs and tissues such as the thyroid, lungs, skin, stomach, intestines, and pancreas. Although their physiological function is not yet fully understood, it appears that they can help regulate the body's homeostasis and provide an additional defense function against pathogens. Since the vast majority of drugs are bitter, the greatest pharmacological interest is in the bitter taste receptors. In this review, we describe how bitter taste 2 receptors (TAS2Rs) induce bronchodilation and mucociliary clearance in the airways, muscle relaxation in various tissues, inhibition of thyroid stimulating hormone (TSH) in thyrocytes, and release of glucagon-like peptide-1 (GLP-1) and ghrelin in the digestive system. In fact, substances such as dextromethorphan, chloroquine, methimazole and probably glimepiride, being agonists of TAS2Rs, lead to these effects. TAS2Rs and taste 1 receptors (TAS1R2/3) are G protein-coupled receptors (GPCR). TAS1R2/3 are responsible for sweet taste perception and may induce GLP-1 release and insulin secretion. Umami taste receptors, belonging to the same superfamily of receptors, perform a similar function with regard to insulin. The sour and salty taste receptors work in a similar way, both being channel receptors sensitive to amiloride. Finally, gene-protein coupled receptor 40 (GPR40) and GPR120 for fatty taste perception are also protein-coupled receptors and may induce GLP-1 secretion and insulin release, similar to those of other receptors belonging to the same superfamily.
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Affiliation(s)
- Ottavio D'Urso
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via S. Sofia, 97, 95125 Catania, Italy
| | - Filippo Drago
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via S. Sofia, 97, 95125 Catania, Italy.
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28
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Govindan R, Banerjee P, Dhania NK, Senapati S. FTIR based approach to study EnaC mechanosensory functions. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 167:79-86. [PMID: 34293339 DOI: 10.1016/j.pbiomolbio.2021.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 10/20/2022]
Abstract
The pulmonary epithelial sodium ion channel (ENaC) is gaining importance for its sodium gating and mechanosensitive roles. The mechano functional studies on ENaC suggest direct molecular interactions between the ENaC protein with cytoskeleton microtubules and other extracellular matrix components. Also, in few mechanotransduction studies, ENaC was shown to respond both to membrane stretch as well as cell volume changes. However, the conformational characteristic of ENaC during sodium and mechano gating are yet to be fully elucidated. Thus obtaining ENaC protein conformational spectrum based on Fourier Transform Infrared Radiation (FTIR) spectroscopy in solution will be useful in predicting the nature of conformational changes occurring during any cell volume changes in an epithelial cell. The conformational spectrum looks promising in studying the disease biology of cystic fibrosis (CF) and CF like conditions that arise due to abnormal ion conductance membrane proteins and subsequent frequent fluid retentions. This review article presents the basics of epithelial ENaC protein as a gated mechanosensor and FTIR for developing fluid dynamics of ENaC protein. This can be applied to develop an ENaC based quantum mechanosensor for the prognosis as well as diagnosis of cystic fibrosis (CF) and allied lung diseases.
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Affiliation(s)
- Rekha Govindan
- Department of Biochemistry, PM Sayeed Calicut University Centre, Andrott, Lakshadweep, 682551, India
| | - Pratibha Banerjee
- Department of Human Genetics & Molecular Medicine, Central University of Punjab, Bathinda, 151401, India
| | - Narender K Dhania
- Department of Human Genetics & Molecular Medicine, Central University of Punjab, Bathinda, 151401, India.
| | - Sabyasachi Senapati
- Department of Human Genetics & Molecular Medicine, Central University of Punjab, Bathinda, 151401, India
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29
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Corrêa JWN, Boaro KR, Sene LB, Polidoro JZ, Salles TA, Martins FL, Bendhack LM, Girardi ACC. Antiproteinuric and Hyperkalemic Mechanisms Activated by Dual Versus Single Blockade of the RAS in Renovascular Hypertensive Rats. Front Physiol 2021; 12:656460. [PMID: 34177612 PMCID: PMC8221266 DOI: 10.3389/fphys.2021.656460] [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: 01/20/2021] [Accepted: 04/09/2021] [Indexed: 11/24/2022] Open
Abstract
This study aimed to investigate the antiproteinuric and hyperkalemic mechanisms activated by dual renin-angiotensin system (RAS) blockade in renovascular hypertensive rats (2-kidney 1-clip model [2K-1C]). Six weeks after clipping the left renal artery or sham operation (2K), rats were treated with losartan, enalapril, or both drugs for two weeks. We found that 2K-1C rats displayed higher tail-cuff blood pressure (BP), increased non-clipped kidney Ang II concentration, and more pronounced urinary albumin excretion than 2K. BP was decreased by the treatment with either enalapril or losartan, and the combination of both drugs promoted an additional antihypertensive effect in 2K-1C rats. Renal Ang II content and albuminuria were reduced by either enalapril or losartan in monotherapy and restored to control levels by dual RAS blockade. Albuminuria in 2K-1C rats was accompanied by downregulation of the glomerular slit protein podocin, reduction of the endocytic receptors megalin and cubilin, and a marked decrease in the expression of the ClC-5 chloride channel, compared to 2K animals. Treatment with losartan and enalapril in monotherapy or combination increased the expression of podocin, cubilin, and ClC-5. However, only the combined therapy normalized podocin, cubilin, and ClC-5 protein abundance in the non-clipped kidney of 2K-1C rats. Renovascular hypertensive 2K-1C rats had a lower concentration of plasma potassium compared to 2K rats. Single RAS blockade normalized potassium plasma concentration, whereas 2K-1C rats treated with dual RAS blockade exhibited hyperkalemia. Hypokalemia in 2K-1C rats was accompanied by an increase in the cleaved activated forms of α-ENaC and γ-ENaC and the expression of β-ENaC. Combined RAS blockade but not monotherapy significantly reduced the expression of these ENaC subunits in 2K-1C rats. Indeed, double RAS blockade reduced the abundance of cleaved-α-ENaC to levels lower than those of 2K rats. Collectively, these results demonstrate that the antiproteinuric effect of dual RAS blockade in 2K-1C rats is associated with the restored abundance of podocin and cubilin, and ClC-5. Moreover, double RAS blockade-induced hyperkalemia may be due, at least partially, to an exaggerated downregulation of cleaved α-ENaC in the non-clipped kidney of renovascular hypertensive rats.
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Affiliation(s)
- José Wilson N Corrêa
- Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor) University of São Paulo Medical School, São Paulo, Brazil.,Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Amazonas, Manaus, Brazil
| | - Karoline R Boaro
- Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor) University of São Paulo Medical School, São Paulo, Brazil
| | - Letícia B Sene
- Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor) University of São Paulo Medical School, São Paulo, Brazil
| | - Juliano Z Polidoro
- Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor) University of São Paulo Medical School, São Paulo, Brazil
| | - Thiago A Salles
- Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor) University of São Paulo Medical School, São Paulo, Brazil
| | - Flavia L Martins
- Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor) University of São Paulo Medical School, São Paulo, Brazil
| | - Lusiane M Bendhack
- Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Adriana C C Girardi
- Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor) University of São Paulo Medical School, São Paulo, Brazil
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30
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Abstract
The Epithelial Na+ Channel, ENaC, comprised of 3 subunits (αβγ, or sometimes δβγENaC), plays a critical role in regulating salt and fluid homeostasis in the body. It regulates fluid reabsorption into the blood stream from the kidney to control blood volume and pressure, fluid absorption in the lung to control alveolar fluid clearance at birth and maintenance of normal airway surface liquid throughout life, and fluid absorption in the distal colon and other epithelial tissues. Moreover, recent studies have also revealed a role for sodium movement via ENaC in nonepithelial cells/tissues, such as endothelial cells in blood vessels and neurons. Over the past 25 years, major advances have been made in our understanding of ENaC structure, function, regulation, and role in human disease. These include the recently solved three-dimensional structure of ENaC, ENaC function in various tissues, and mutations in ENaC that cause a hereditary form of hypertension (Liddle syndrome), salt-wasting hypotension (PHA1), or polymorphism in ENaC that contributes to other diseases (such as cystic fibrosis). Moreover, great strides have been made in deciphering the regulation of ENaC by hormones (e.g., the mineralocorticoid aldosterone, glucocorticoids, vasopressin), ions (e.g., Na+ ), proteins (e.g., the ubiquitin-protein ligase NEDD4-2, the kinases SGK1, AKT, AMPK, WNKs & mTORC2, and proteases), and posttranslational modifications [e.g., (de)ubiquitylation, glycosylation, phosphorylation, acetylation, palmitoylation]. Characterization of ENaC structure, function, regulation, and role in human disease, including using animal models, are described in this article, with a special emphasis on recent advances in the field. © 2021 American Physiological Society. Compr Physiol 11:1-29, 2021.
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Affiliation(s)
- Daniela Rotin
- The Hospital for Sick Children, and The University of Toronto, Toronto, Canada
| | - Olivier Staub
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
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31
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Carroll EL, Bailo M, Reihill JA, Crilly A, Lockhart JC, Litherland GJ, Lundy FT, McGarvey LP, Hollywood MA, Martin SL. Trypsin-Like Proteases and Their Role in Muco-Obstructive Lung Diseases. Int J Mol Sci 2021; 22:5817. [PMID: 34072295 PMCID: PMC8199346 DOI: 10.3390/ijms22115817] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022] Open
Abstract
Trypsin-like proteases (TLPs) belong to a family of serine enzymes with primary substrate specificities for the basic residues, lysine and arginine, in the P1 position. Whilst initially perceived as soluble enzymes that are extracellularly secreted, a number of novel TLPs that are anchored in the cell membrane have since been discovered. Muco-obstructive lung diseases (MucOLDs) are characterised by the accumulation of hyper-concentrated mucus in the small airways, leading to persistent inflammation, infection and dysregulated protease activity. Although neutrophilic serine proteases, particularly neutrophil elastase, have been implicated in the propagation of inflammation and local tissue destruction, it is likely that the serine TLPs also contribute to various disease-relevant processes given the roles that a number of these enzymes play in the activation of both the epithelial sodium channel (ENaC) and protease-activated receptor 2 (PAR2). More recently, significant attention has focused on the activation of viruses such as SARS-CoV-2 by host TLPs. The purpose of this review was to highlight key TLPs linked to the activation of ENaC and PAR2 and their association with airway dehydration and inflammatory signalling pathways, respectively. The role of TLPs in viral infectivity will also be discussed in the context of the inhibition of TLP activities and the potential of these proteases as therapeutic targets.
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Affiliation(s)
- Emma L. Carroll
- School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK; (E.L.C.); (J.A.R.)
| | - Mariarca Bailo
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - James A. Reihill
- School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK; (E.L.C.); (J.A.R.)
| | - Anne Crilly
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - John C. Lockhart
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - Gary J. Litherland
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - Fionnuala T. Lundy
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University, Belfast BT9 7BL, UK; (F.T.L.); (L.P.M.)
| | - Lorcan P. McGarvey
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University, Belfast BT9 7BL, UK; (F.T.L.); (L.P.M.)
| | - Mark A. Hollywood
- Smooth Muscle Research Centre, Dundalk Institute of Technology, A91 HRK2 Dundalk, Ireland;
| | - S. Lorraine Martin
- School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK; (E.L.C.); (J.A.R.)
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32
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Salleh N, Ismail N, Nelli G, Myint K, Khaing SL. Changes in fluid composition and expression of ion channels in rat cervix during different phases of the estrus cycle. Biotech Histochem 2021; 97:53-66. [PMID: 33827344 DOI: 10.1080/10520295.2021.1899285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
We investigated changes in the composition of cervical fluid at different phases of the female rat reproductive cycle. Fluid was collected from the cervix of rats by direct cervical flushing and analyzed for changes in Na+ and Cl- content and osmolarity. Following sacrifice, the cervix was harvested and expressions of mRNA and protein for ENaCs, CFTR and AQPs were measured using qPCR and immunohistochemistry, respectively. Cervical fluid Na+ and Cl- content was high during estrus, but osmolarity was high during metestrus and diestrus. Expressions of CFTR, AQP-1 and AQP-2 in the cervix were high during estrus, but low during diestrus. Expression of ENaC (α, β, γ), AQP-5 and AQP-7 was high during metestrus and diestrus and low during estrus. Changes in expression of ion channels in the cervix could explain changes in cervical fluid composition during the estrus cycle phases that could affect female fertility.
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Affiliation(s)
- Naguib Salleh
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Nurain Ismail
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Giribabu Nelli
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kyaimon Myint
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Si Lay Khaing
- Department of Obstetrics & Gynecology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.,Medical Education Department, University of Medicine, Yangon, Myanmar
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33
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Effects of SGLT2 inhibitor ipragliflozin alone and combined with pioglitazone on fluid retention in type 2 diabetic mice with NASH. Eur J Pharmacol 2021; 901:174076. [PMID: 33798599 DOI: 10.1016/j.ejphar.2021.174076] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/22/2021] [Accepted: 03/26/2021] [Indexed: 12/12/2022]
Abstract
Several antidiabetic agents, including thiazolidinediones and sodium-glucose cotransporter (SGLT) 2 inhibitors, attenuate the symptoms of nonalcoholic steatohepatitis (NASH). However, thiazolidinediones have serious side effects such as fluid retention and increased risk of congestive heart failure. We examined the effects of SGLT2 inhibitor ipragliflozin, pioglitazone, and ipragliflozin + pioglitazone on fluid retention in type 2 diabetic mice with NASH. Four-week repeated administration of pioglitazone caused significant increases in heart weight (31% increase in 30 mg/kg pioglitazone-treated group compared to vehicle-treated group) concomitant with fluid retention, as estimated by a decrease in plasma osmolality and increase in water intake/urine volume ratio. In addition, pioglitazone significantly increased (by 1.5 to 2-fold) mRNA expression of α, β, and γ subtypes of ENaC and AQP2 and 3 subtypes in the renal medulla. Thus, pioglitazone-induced fluid retention may arise from enhanced reabsorption of sodium and water associated with increased expression of these channels in the kidney. In contrast, ipragliflozin alone did not induce these symptoms and did not affect ENaC or AQP expression. Combination treatment with ipragliflozin + pioglitazone attenuated these symptoms by ipragliflozin-induced osmotic diuresis. These findings demonstrate that treatment with ipragliflozin monotherapy or coadministered with pioglitazone may be a potential therapeutic option for the treatment of type 2 diabetes with NASH without fluid retention as a side effect.
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34
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Hartati YW, Komala DR, Hendrati D, Gaffar S, Hardianto A, Sofiatin Y, Bahti HH. An aptasensor using ceria electrodeposited-screen-printed carbon electrode for detection of epithelial sodium channel protein as a hypertension biomarker. ROYAL SOCIETY OPEN SCIENCE 2021; 8:202040. [PMID: 33972878 PMCID: PMC8074578 DOI: 10.1098/rsos.202040] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 01/20/2021] [Indexed: 06/02/2023]
Abstract
Epithelial sodium channel (ENaC) is a transmembrane protein that has an essential role in maintaining the levels of sodium in blood plasma. A person with a family history of hypertension has a high enough amount of ENaC protein in the kidneys or other organs, so that the ENaC protein acts as a marker that a person is susceptible to hypertension. An aptasensor involves aptamers, which are oligonucleotides that function similar to antibodies, as sensing elements. An electrochemical aptasensor for the detection of ENaC was developed using a screen-printed carbon electrode (SPCE) which was modified by electrodeposition of cerium oxide (CeO2). The aptamer immobilization was via the streptavidin-biotin system. The measurement of changes in current of the active redox [Fe(CN)6]3-/4- was carried out by differential pulse voltammetry. The surfaces of SPCE and SPCE/CeO2 were characterized using scanning electron microscopy, voltammetry and electrochemical impedance spectroscopy. The Box-Behnken experimental optimization design revealed the streptavidin incubation time, aptamer incubation time and streptavidin concentrations were 30 min, 30 min and 10.8 µg ml-1, respectively. Various concentrations of ENaC were used to obtain the linearity range of 0.05-3.0 ng ml-1, and the limits of detection and quantification were 0.012 ng ml-1 and 0.038 ng ml-1, respectively. This aptasensor method has the potential to measure the ENaC protein levels in urine samples as well as to be a point-of-care device.
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Affiliation(s)
- Yeni Wahyuni Hartati
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Bandung, Indonesia
| | - Dina Ratna Komala
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Bandung, Indonesia
| | - Diana Hendrati
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Bandung, Indonesia
| | - Shabarni Gaffar
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Bandung, Indonesia
| | - Ari Hardianto
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Bandung, Indonesia
| | - Yulia Sofiatin
- Department of Public Health, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Husein Hernandi Bahti
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Bandung, Indonesia
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35
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Gray Z, Tu W, Chertow GM, Bhalla V. Aldosterone sensitivity: an opportunity to explore the pathogenesis of hypertension. Am J Physiol Renal Physiol 2021; 320:F325-F335. [PMID: 33491565 DOI: 10.1152/ajprenal.00415.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aldosterone sensitivity is defined as an outcome variable for a given circulating level of aldosterone. In basic and translational studies, aldosterone sensitivity has been measured in differential tissue responses, e.g., lower urine sodium and higher urine potassium, as an index of the renal response; in clinical studies, aldosterone sensitivity has been measured in differential blood pressure responses. The concept of aldosterone sensitivity disrupts the conventional wisdom of the renin-angiotensin-aldosterone system and has the potential to uncover novel mechanisms of hypertension. Here, we review basic and translational science studies that uncovered differential renal responses to aldosterone and connect this earlier work to more recent observational studies and randomized trials that have demonstrated differential blood pressure responses for a given level of aldosterone in healthy and hypertensive persons. Black race and older age are associated with higher aldosterone sensitivity and blood pressure. We also discuss gaps in the field and how future basic and clinical studies might inform mechanisms of differential sensitivity.
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Affiliation(s)
- Zachary Gray
- Stanford Hypertension Center, Stanford University School of Medicine, Stanford, California
| | - Wanzhu Tu
- Department of Biostatistics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Glenn M Chertow
- Stanford Hypertension Center, Stanford University School of Medicine, Stanford, California.,Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California
| | - Vivek Bhalla
- Stanford Hypertension Center, Stanford University School of Medicine, Stanford, California.,Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California
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36
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Kim M, Lee SW, Kim J, Shin Y, Chang F, Kim JM, Cong X, Yu GY, Park K. LPS-induced epithelial barrier disruption via hyperactivation of CACC and ENaC. Am J Physiol Cell Physiol 2021; 320:C448-C461. [PMID: 33471620 DOI: 10.1152/ajpcell.00295.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Gram-negative bacterial lipopolysaccharide (LPS) increases the susceptibility of cells to pathogenic diseases, including inflammatory diseases and septic syndrome. In our experiments, we examined whether LPS induces epithelial barrier disruption in secretory epithelia and further investigated its underlying mechanism. The activities of Ca2+-activated Cl- channels (CACC) and epithelial Na+ channels (ENaC) were monitored with a short-circuit current using an Ussing chamber. Epithelial membrane integrity was estimated via transepithelial electrical resistance and paracellular permeability assays. We found that the apical application of LPS evoked short-circuit current (Isc) through the activation of CACC and ENaC. Although LPS disrupted epithelial barrier integrity, this was restored with the inhibition of CACC and ENaC, indicating the role of CACC and ENaC in the regulation of paracellular pathways. We confirmed that LPS, CACC, or ENaC activation evoked apical membrane depolarization. The exposure to a high-K+ buffer increased paracellular permeability. LPS induced the rapid redistribution of zonula occludens-1 (ZO-1) and reduced the expression levels of ZO-1 in tight junctions through apical membrane depolarization and tyrosine phosphorylation. However, the LPS-induced epithelial barrier disruption and degradation of ZO-1 were largely recovered by blocking CACC and ENaC. Furthermore, although LPS-impaired epithelial barrier became vulnerable to secondary bacterial infections, this vulnerability was prevented by inhibiting CACC and ENaC. We concluded that LPS induces the disruption of epithelial barrier integrity through the activation of CACC and ENaC, resulting in apical membrane depolarization and the subsequent tyrosine phosphorylation of ZO-1.
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Affiliation(s)
- Minkyoung Kim
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul, South Korea
| | - Sang-Woo Lee
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul, South Korea
| | - Junchul Kim
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul, South Korea
| | - Yonghwan Shin
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul, South Korea
| | - Fengjiao Chang
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul, South Korea
| | - Jin Man Kim
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul, South Korea
| | - Xin Cong
- Department of Physiology and Pathophysiology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Guang-Yan Yu
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China
| | - Kyungpyo Park
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul, South Korea
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Chan CH, Wu SN, Bao BY, Li HW, Lu TL. MST3 Involvement in Na + and K + Homeostasis with Increasing Dietary Potassium Intake. Int J Mol Sci 2021; 22:ijms22030999. [PMID: 33498219 PMCID: PMC7863938 DOI: 10.3390/ijms22030999] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 02/07/2023] Open
Abstract
K+ loading inhibits NKCC2 (Na-K-Cl cotransporter) and NCC (Na-Cl cotransporter) in the early distal tubules, resulting in Na+ delivery to the late distal convoluted tubules (DCTs). In the DCTs, Na+ entry through ENaC (epithelial Na channel) drives K+ secretion through ROMK (renal outer medullary potassium channel). WNK4 (with-no-lysine 4) regulates the NCC/NKCC2 through SAPK (Ste20-related proline-alanine-rich kinase)/OSR1 (oxidative stress responsive). K+ loading increases intracellular Cl−, which binds to the WNK4, thereby inhibiting autophosphorylation and downstream signals. Acute K+ loading-deactivated NCC was not observed in Cl−-insensitive WNK4 mice, indicating that WNK4 was involved in K+ loading-inhibited NCC activity. However, chronic K+ loading deactivated NCC in Cl−-insensitive WNK4 mice, indicating that other mechanisms may be involved. We previously reported that mammalian Ste20-like protein kinase 3 (MST3/STK24) was expressed mainly in the medullary TAL (thick ascending tubule) and at lower levels in the DCTs. MST3−/− mice exhibited higher ENaC activity, causing hypernatremia and hypertension. To investigate MST3 function in maintaining Na+/K+ homeostasis in kidneys, mice were fed diets containing various concentrations of Na+ and K+. The 2% KCl diets induced less MST3 expression in MST3−/− mice than that in wild-type (WT) mice. The MST3−/− mice had higher WNK4, NKCC2-S130 phosphorylation, and ENaC expression, resulting in lower urinary Na+ and K+ excretion than those of WT mice. Lower urinary Na+ excretion was associated with elevated plasma [Na+] and hypertension. These results suggest that MST3 maintains Na+/K+ homeostasis in response to K+ loading by regulation of WNK4 expression and NKCC2 and ENaC activity.
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Affiliation(s)
- Chee-Hong Chan
- Department of Nephrology, Chang Bing Show Chwan Memorial Hospital, Lukang, Changhua 505, Taiwan;
| | - Sheng-Nan Wu
- Department of Physiology, National Cheng Kung University Medical College, Tainan 70101, Taiwan;
| | - Bo-Ying Bao
- School of Pharmacy, China Medical University, Taichung 406040, Taiwan;
- Department of Nursing, Asia University, Taichung 41354, Taiwan
| | - Houng-Wei Li
- Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 406040, Taiwan;
| | - Te-Ling Lu
- School of Pharmacy, China Medical University, Taichung 406040, Taiwan;
- Correspondence:
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Ayasse N, Berg P, Leipziger J, Sørensen MV. ENaC expression correlates with the acute furosemide-induced K + excretion. Physiol Rep 2021; 9:e14668. [PMID: 33410279 PMCID: PMC7788322 DOI: 10.14814/phy2.14668] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND In the aldosterone-sensitive distal nephron (ASDN), epithelial sodium channel (ENaC)-mediated Na+ absorption drives K+ excretion. K+ excretion depends on the delivery of Na+ to the ASDN and molecularly activated ENaC. Furosemide is known as a K+ wasting diuretic as it greatly enhances Na+ delivery to the ASDN. Here, we studied the magnitude of acute furosemide-induced kaliuresis under various states of basal molecular ENaC activity. METHODS C57/Bl6J mice were subjected to different dietary regimens that regulate molecular ENaC expression and activity levels. The animals were anesthetized and bladder-catheterized. Diuresis was continuously measured before and after administration of furosemide (2 µg/g BW) or benzamil (0.2 µg/g BW). Flame photometry was used to measure urinary [Na+ ] and [K+ ]. The kidneys were harvested and, subsequently, ENaC expression and cleavage activation were determined by semiquantitative western blotting. RESULTS A low K+ and a high Na+ diet markedly suppressed ENaC protein expression, cleavage activation, and furosemide-induced kaliuresis. In contrast, furosemide-induced kaliuresis was greatly enhanced in animals fed a high K+ or low Na+ diet, conditions with increased ENaC expression. The furosemide-induced diuresis was similar in all dietary groups. CONCLUSION Acute furosemide-induced kaliuresis differs greatly and depends on the a priori molecular expression level of ENaC. Remarkably, it can be even absent in animals fed a high Na+ diet, despite a marked increase of tubular flow and urinary Na+ excretion. This study provides auxiliary evidence that acute ENaC-dependent K+ excretion requires both Na+ as substrate and molecular activation of ENaC.
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Affiliation(s)
- Niklas Ayasse
- Department of Biomedicine, PhysiologyAarhus UniversityAarhus CDenmark
| | - Peder Berg
- Department of Biomedicine, PhysiologyAarhus UniversityAarhus CDenmark
| | - Jens Leipziger
- Department of Biomedicine, PhysiologyAarhus UniversityAarhus CDenmark
- Aarhus Institute of Advanced StudiesAarhus UniversityAarhus CDenmark
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Khayyat NH, Zaika O, Tomilin VN, Pyrshev K, Pochynyuk O. Angiotensin II increases activity of the ClC-K2 Cl - channel in collecting duct intercalated cells by stimulating production of reactive oxygen species. J Biol Chem 2021; 296:100347. [PMID: 33524393 PMCID: PMC7949157 DOI: 10.1016/j.jbc.2021.100347] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 01/11/2023] Open
Abstract
The renal collecting duct plays a critical role in setting urinary volume and composition, with principal cells transporting Na+ and K+ and intercalated cells mediating Cl- reabsorption. Published evidence implies Angiotensin II (Ang II) is a potent regulator of the collecting duct apical transport systems in response to systemic volume depletion. However, virtually nothing is known about Ang II actions on the basolateral conductance of principal and intercalated cells. Here, we combined macroscopic and single channel patch clamp recordings from freshly isolated mouse collecting ducts with biochemical and fluorescence methods to demonstrate an acute stimulation of the basolateral Cl- conductance and specifically the ClC-K2 Cl- channel by nanomolar Ang II concentrations in intercalated cells. In contrast, Ang II did not exhibit measurable effects on the basolateral conductance and on Kir4.1/5.1 potassium channel activity in principal cells. Although both Ang II receptors AT1 and AT2 are expressed in collecting duct cells, we show that AT1 receptors were essential for stimulatory actions of Ang II on ClC-K2. Moreover, AT1R-/- mice had decreased renal ClC-K2 expression. We further demonstrated that activation of NADPH oxidases is the major signaling pathway downstream of Ang II-AT1R that leads to stimulation of ClC-K2. Treatment of freshly isolated collecting ducts with Ang II led to production of reactive oxygen species on the same timescale as single channel ClC-K2 activation. Overall, we propose that Ang II-dependent regulation of ClC-K2 in intercalated cells is instrumental for stimulation of Cl- reabsorption by the collecting duct, particularly during hypovolemic states.
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Affiliation(s)
- Naghmeh Hassanzadeh Khayyat
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Oleg Zaika
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Viktor N Tomilin
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Kyrylo Pyrshev
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Oleh Pochynyuk
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA.
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High blood pressure induced by vitamin D deficiency is associated with renal overexpression and hyperphosphorylation of Na+-K+-2Cl- cotransporter type 2. J Hypertens 2020; 39:880-891. [PMID: 33337598 DOI: 10.1097/hjh.0000000000002745] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Clinical and epidemiological studies have suggested a correlation between vitamin D deficiency (VDD) and high blood pressure (BP). This study aimed to test the hypothesis that high BP induced by VDD is associated with altered expression and covalent modification of apical sodium transporters along the nephron. The contributions of the intrarenal renin-angiotensin system (RAS) and oxidative stress were also investigated. METHODS Male Wistar rats were fed a vitamin D-free (n = 26) or standard diet (n = 25) for 30 days. BP was recorded using noninvasive and invasive procedures. The expression levels of total and phosphorylated apical sodium transporters in rat renal cortex and medulla were evaluated by immunoblotting. Intrarenal RAS components were assessed by immunoblotting and ELISA. Renal oxidative stress was analyzed by measuring the concentrations of thiobarbituric acid reactive substances and reduced glutathione. RESULTS Higher BP levels in VDD rats than controls were accompanied by overexpression and hyperphosphorylation of renal cortical and medullary Na+-K+-2Cl- cotransporter type 2, enhanced levels of phosphorylated Na+/H+ exchanger type 3, and reduced expression levels of total and phosphorylated Na+/Cl- cotransporter. Changes in intrarenal RAS induced by VDD vs. controls included the marked elevation of medullary renin expression, higher expression of cortical angiotensinogen, higher urinary angiotensinogen excretion, and higher cortical and medullary angiotensin II content. VDD rats displayed higher thiobarbituric acid reactive substances/glutathione ratios in the renal cortex and medulla than controls. CONCLUSION These results suggest that the molecular mechanisms underlying the effects of VDD on BP may include the upregulation of Na+-K+-2Cl- cotransporter type 2 and activation of intrarenal RAS and oxidative stress.
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Komala DR, Hardianto A, Gaffar S, Hartati YW. An Epithelial Sodium Channel (ENaC)-Specific Aptamer Determined through Structure-Based Virtual Screening for the Development of Hypertension Early Detection System. PHARMACEUTICAL SCIENCES 2020. [DOI: 10.34172/ps.2020.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Background: Epithelial sodium channel (ENaC) is a transmembrane protein involved in maintaining sodium levels in blood plasma. It is also a potential biomarker for the early detection of hypertension since the amount of ENaC is related to the familial history of hypertension. ENaC can be detected by an aptamer, a single-stranded DNA (ssDNA) or RNA which offers advantages over an antibody. This study aimed to obtain an ssDNA aptamer specific to ENaC through virtual screening. Methods: Forty-one aptamers were retrieved from the Protein Data Bank (PDB) and the RNA was converted to ssDNA aptamers. The X-ray crystallographic structure of ENaC protein was remodelled using Modeller 9.20 to resolve missing residues. Molecular docking of aptamers against ENaC was performed using Patchdock and Firedock, then the selected aptamer was subjected to molecular docking against other ion channel proteins to assess its selectivity to ENaC. A molecular dynamics (MD) simulation was also conducted using Amber16 to acquire an in-depth understanding of the interaction within the aptamer-ENaC complex. Results: The virtual screening suggested that the ssDNA of iSpinach aptamer (PDB: 5OB3) displayed the strongest binding to ENaC (-49.46 kcal/mol) and was selective for ENaC over the other ion protein channels. An MMGBSA calculation on the complex of aptamer-ENaC revealed binding energy of -42,12 kcal/mol. Conclusion: The iSpinach-based aptamer is a potential probe for detecting ENaC or iDE and may be useful for the development of hypertension early detection systems.
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Affiliation(s)
- Dina Ratna Komala
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Indonesia
| | - Ari Hardianto
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Indonesia
| | - Shabarni Gaffar
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Indonesia
| | - Yeni Wahyuni Hartati
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Indonesia
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Abstract
PURPOSE OF REVIEW The main goal of this article is to discuss the role of the epithelial sodium channel (ENaC) in extracellular fluid and blood pressure regulation. RECENT FINDINGS Besides its role in sodium handling in the kidney, recent studies have found that ENaC expressed in other cells including immune cells can influence blood pressure via extra-renal mechanisms. Dendritic cells (DCs) are activated and contribute to salt-sensitive hypertension in an ENaC-dependent manner. We discuss recent studies on how ENaC is regulated in both the kidney and other sites including the vascular smooth muscles, endothelial cells, and immune cells. We also discuss how this extra-renal ENaC can play a role in salt-sensitive hypertension and its promise as a novel therapeutic target. The role of ENaC in blood pressure regulation in the kidney has been well studied. Recent human gene sequencing efforts have identified thousands of variants among the genes encoding ENaC, and research efforts to determine if these variants and their expression in extra-renal tissue play a role in hypertension will advance our understanding of the pathogenesis of ENaC-mediated cardiovascular disease and lead to novel therapeutic targets.
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Affiliation(s)
- Ashley L Pitzer
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Avenue, P415C Medical Research Building IV, Nashville, TN, 37232, USA
| | - Justin P Van Beusecum
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Avenue, P415C Medical Research Building IV, Nashville, TN, 37232, USA
| | - Thomas R Kleyman
- Departments of Medicine, Cell Biology, Pharmacology, and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Annet Kirabo
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Avenue, P415C Medical Research Building IV, Nashville, TN, 37232, USA. .,Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA.
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Olivença DV, Voit EO, Pinto FR. ENaC regulation by phospholipids and DGK explained through mathematical modeling. Sci Rep 2020; 10:13952. [PMID: 32811866 PMCID: PMC7435262 DOI: 10.1038/s41598-020-70630-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/21/2020] [Indexed: 01/16/2023] Open
Abstract
Cystic fibrosis is a condition caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR). It is also thought to increase the activity of epithelial sodium channels (ENaC). The altered function of these ion channels is one of the causes of the thick dehydrated mucus that characterizes the disease and is partially responsible for recurrent pulmonary infections and inflammation events that ultimately destroy the lungs of affected subjects. Phosphoinositides are signaling lipids that regulate numerous cellular processes and membrane proteins, including ENaC. Inhibition of diacylglycerol kinase (DGK), an enzyme of the phosphoinositide pathway, reduces ENaC function. We propose a computational analysis that is based on the combination of two existing mathematical models: one representing the dynamics of phosphoinositides and the other explaining how phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) influences ENaC activity and, consequently, airway surface liquid. This integrated model permits, for the first time, a detailed assessment of the intricate interactions between DGK and ENaC and is consistent with available literature data. In particular, the computational approach allows comparisons of two competing hypotheses regarding the regulation of ENaC. The results strongly suggest that the regulation of ENaC is primarily exerted through the control of PI(4,5)P2 production by type-I phosphatidylinositol-4-phosphate 5-kinase (PIP5KI), which in turn is controlled by phosphatidic acid (PA), the product of the DGK reaction.
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Affiliation(s)
- Daniel V. Olivença
- Faculty of Sciences, BioISI – Biosystems and Integrative Sciences Institute, University of Lisboa, 1749-016 Lisbon, Portugal
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 950 Atlantic Drive, Atlanta, GA 30332-2000 USA
| | - Eberhard O. Voit
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 950 Atlantic Drive, Atlanta, GA 30332-2000 USA
| | - Francisco R. Pinto
- Faculty of Sciences, BioISI – Biosystems and Integrative Sciences Institute, University of Lisboa, 1749-016 Lisbon, Portugal
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Autologous transplantation of adipose-derived stromal cells combined with sevoflurane ameliorates acute lung injury induced by cecal ligation and puncture in rats. Sci Rep 2020; 10:13760. [PMID: 32792558 PMCID: PMC7426944 DOI: 10.1038/s41598-020-70767-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 08/04/2020] [Indexed: 02/07/2023] Open
Abstract
Adipose-derived stromal cells (ADSCs) have excellent capacities for regeneration and tissue protection, while sevoflurane, as a requisite component of surgical procedures, has shown therapeutic benefit in animal models of sepsis. This study therefore determined if the combination of sevoflurane and ADSCs exerted additional protective effects against acute lung injury (ALI) induced by cecal ligation and puncture (CLP) in rats. The animals were randomized into five groups: (sham operation (group I), CLP followed by mechanical ventilation (group II), CLP plus sevoflurane at 0.5 minimum alveolar concentration (group III), CLP plus intravenous autologous 5 × 106 ADSCs (group IV), and CLP plus sevoflurane and ADSCs (group V). Levels of the pro-inflammatory cytokines tumor necrosis factor-α, transforming growth factor-β1, interleukin-1β and interleukin-6 were significantly increased in CLP rats. Moreover, epithelial sodium channel expression levels and activities of Na/K-ATPase and alveolar fluid clearance were significantly reduced in CLP-induced ALI rats. ADSCs improved all these parameters, and these effects were further enhanced by the addition of sevoflurane. In conclusion, combined treatment with ADSCs and sevoflurane is superior to either ADSCs or sevoflurane therapy alone for preventing ALI. This beneficial effect may be partly due to improved alveolar fluid clearance by the paracrine or systemic production of keratinocyte growth factor and via anti-inflammatory properties.
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García‐Rubio DL, de la Mora M, Cerecedo D, Saniger Blesa JM, Villagrán‐Muniz M. An optical-based biosensor of the epithelial sodium channel as a tool for diagnosing hypertension. Biosens Bioelectron 2020; 157:112151. [DOI: 10.1016/j.bios.2020.112151] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 03/04/2020] [Accepted: 03/11/2020] [Indexed: 01/22/2023]
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Drosophila as a model for studying cystic fibrosis pathophysiology of the gastrointestinal system. Proc Natl Acad Sci U S A 2020; 117:10357-10367. [PMID: 32345720 DOI: 10.1073/pnas.1913127117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Cystic fibrosis (CF) is a recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The most common symptoms include progressive lung disease and chronic digestive conditions. CF is the first human genetic disease to benefit from having five different species of animal models. Despite the phenotypic differences among the animal models and human CF, these models have provided invaluable insight into understanding disease mechanisms at the organ-system level. Here, we identify a member of the ABCC4 family, CG5789, that has the structural and functional properties expected for encoding the Drosophila equivalent of human CFTR, and thus refer to it as Drosophila CFTR (Dmel\CFTR). We show that knockdown of Dmel\CFTR in the adult intestine disrupts osmotic homeostasis and displays CF-like phenotypes that lead to intestinal stem cell hyperplasia. We also show that expression of wild-type human CFTR, but not mutant variants of CFTR that prevent plasma membrane expression, rescues the mutant phenotypes of Dmel\CFTR Furthermore, we performed RNA sequencing (RNA-Seq)-based transcriptomic analysis using Dmel\CFTR fly intestine and identified a mucin gene, Muc68D, which is required for proper intestinal barrier protection. Altogether, our findings suggest that Drosophila can be a powerful model organism for studying CF pathophysiology.
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Wu P, Su XT, Gao ZX, Zhang DD, Duan XP, Xiao Y, Staub O, Wang WH, Lin DH. Renal Tubule Nedd4-2 Deficiency Stimulates Kir4.1/Kir5.1 and Thiazide-Sensitive NaCl Cotransporter in Distal Convoluted Tubule. J Am Soc Nephrol 2020; 31:1226-1242. [PMID: 32295826 DOI: 10.1681/asn.2019090923] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 03/07/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The potassium channel Kir4.1 forms the Kir4.1/Kir5.1 heterotetramer in the basolateral membrane of the distal convoluted tubule (DCT) and plays an important role in the regulation of the thiazide-sensitive NaCl cotransporter (NCC). Kidney-specific deletion of the ubiquitin ligase Nedd4-2 increases expression of NCC, and coexpression of Nedd4-2 inhibits Kir4.1/Kir5.1 in vitro. Whether Nedd4-2 regulates NCC expression in part by regulating Kir4.1/Kir5.1 channel activity in the DCT is unknown. METHODS We used electrophysiology studies, immunoblotting, immunostaining, and renal clearance to examine Kir4.1/Kir5.1 activity in the DCT and NCC expression/activity in wild-type mice and mice with kidney-specific knockout of Nedd4-2, Kir4.1, or both. RESULTS Deletion of Nedd4-2 increased the activity/expression of Kir4.1 in the DCT and also, hyperpolarized the DCT membrane. Expression of phosphorylated NCC/total NCC and thiazide-induced natriuresis were significantly increased in the Nedd4-2 knockout mice, but these mice were normokalemic. Double-knockout mice lacking both Kir4.1/Kir5.1 and Nedd4-2 in the kidney exhibited increased expression of the epithelial sodium channel α-subunit, largely abolished basolateral potassium ion conductance (to a degree similar to that of kidney-specific Kir4.1 knockout mice), and depolarization of the DCT membrane. Compared with wild-type mice, the double-knockout mice displayed inhibited expression of phosphorylated NCC and total NCC and had significantly blunted thiazide-induced natriuresis as well as renal potassium wasting and hypokalemia. However, NCC expression/activity was higher in the double-knockout mice than in Kir4.1 knockout mice. CONCLUSIONS Nedd4-2 regulates Kir4.1/Kir5.1 expression/activity in the DCT and modulates NCC expression by Kir4.1-dependent and Kir4.1-independent mechanisms. Basolateral Kir4.1/Kir5.1 activity in the DCT partially accounts for the stimulation of NCC activity/expression induced by deletion of Nedd4-2.
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Affiliation(s)
- Peng Wu
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Xiao-Tong Su
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Zhong-Xiuzi Gao
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Dan-Dan Zhang
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Xin-Peng Duan
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Yu Xiao
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Olivier Staub
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Wen-Hui Wang
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Dao-Hong Lin
- Department of Pharmacology, New York Medical College, Valhalla, New York
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Shi S, Montalbetti N, Wang X, Rush BM, Marciszyn AL, Baty CJ, Tan RJ, Carattino MD, Kleyman TR. Paraoxonase 3 functions as a chaperone to decrease functional expression of the epithelial sodium channel. J Biol Chem 2020; 295:4950-4962. [PMID: 32079677 DOI: 10.1074/jbc.ra119.011789] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/17/2020] [Indexed: 01/11/2023] Open
Abstract
The paraoxonase (PON) family comprises three highly conserved members: PON1, PON2, and PON3. They are orthologs of Caenorhabditis elegans MEC-6, an endoplasmic reticulum-resident chaperone that has a critical role in proper assembly and surface expression of the touch-sensing degenerin channel in nematodes. We have shown recently that MEC-6 and PON2 negatively regulate functional expression of the epithelial Na+ channel (ENaC), suggesting that the chaperone function is conserved within this family. We hypothesized that other PON family members also modulate ion channel expression. Pon3 is specifically expressed in the aldosterone-sensitive distal tubules in the mouse kidney. We found here that knocking down endogenous Pon3 in mouse cortical collecting duct cells enhanced Na+ transport, which was associated with increased γENaC abundance. We further examined Pon3 regulation of ENaC in two heterologous expression systems, Fisher rat thyroid cells and Xenopus oocytes. Pon3 coimmunoprecipitated with each of the three ENaC subunits in Fisher rat thyroid cells. As a result of this interaction, the whole-cell and surface abundance of ENaC α and γ subunits was reduced by Pon3. When expressed in oocytes, Pon3 inhibited ENaC-mediated amiloride-sensitive Na+ currents, in part by reducing the surface expression of ENaC. In contrast, Pon3 did not alter the response of ENaC to chymotrypsin-mediated proteolytic activation or [2-(trimethylammonium)ethyl]methanethiosulfonate-induced activation of αβS518Cγ, suggesting that Pon3 does not affect channel open probability. Together, our results suggest that PON3 regulates ENaC expression by inhibiting its biogenesis and/or trafficking.
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Affiliation(s)
- Shujie Shi
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Nicolas Montalbetti
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Xueqi Wang
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261.,Department of Nephrology, Second Xiangya Hospital of Central South University, Changsha 410011, Hunan, China
| | - Brittney M Rush
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Allison L Marciszyn
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Catherine J Baty
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Roderick J Tan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Marcelo D Carattino
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261.,Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Thomas R Kleyman
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261.,Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261.,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
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49
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Wu P, Gao Z, Zhang D, Duan X, Terker AS, Lin D, Ellison DH, Wang W. Effect of Angiotensin II on ENaC in the Distal Convoluted Tubule and in the Cortical Collecting Duct of Mineralocorticoid Receptor Deficient Mice. J Am Heart Assoc 2020; 9:e014996. [PMID: 32208832 PMCID: PMC7428622 DOI: 10.1161/jaha.119.014996] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 02/18/2020] [Indexed: 12/02/2022]
Abstract
Background Angiotensin II stimulates epithelial Na+ channel (ENaC) by aldosterone-independent mechanism. We now test the effect of angiotensin II on ENaC in the distal convoluted tubule (DCT) and cortical collecting duct (CCD) of wild-type (WT) and kidney-specific mineralocorticoid receptor knockout mice (KS-MR-KO). Methods and Results We used electrophysiological, immunoblotting and renal-clearance methods to examine the effect of angiotensin II on ENaC in KS-MR-KO and wild-type mice. High K+ intake stimulated ENaC in the late DCT/early connecting tubule (DCT2/CNT) and in the CCD whereas low sodium intake stimulated ENaC in the CCD but not in the DCT2/CNT. The deletion of MR abolished the stimulatory effect of high K+ and low sodium intake on ENaC, partially inhibited ENaC in DCT2/CNT but almost abolished ENaC activity in the CCD. Application of losartan inhibited ENaC only in DCT2/CNT of both wild-type and KS-MR-KO mice but not in the CCD. Angiotensin II infusion for 3 days has a larger stimulatory effect on ENaC in the DCT2/CNT than in the CCD. Three lines of evidence indicate that angiotensin II can stimulate ENaC by MR-independent mechanism: (1) angiotensin II perfusion augmented ENaC expression in KS-MR-KO mice; (2) angiotensin II stimulated ENaC in the DCT2/CNT but to a lesser degree in the CCD in KS-MR-KO mice; (3) angiotensin II infusion augmented benzamil-induced natriuresis, increased the renal K+ excretion and corrected hyperkalemia of KS-MR-KO mice. Conclusions Angiotensin II-induced stimulation of ENaC occurs mainly in the DCT2/CNT and to a lesser degree in the CCD and MR plays a dominant role in determining ENaC activity in the CCD but to a lesser degree in the DCT2/CNT.
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MESH Headings
- Angiotensin II/pharmacology
- Animals
- Epithelial Sodium Channels/metabolism
- Hyperkalemia/drug therapy
- Hyperkalemia/genetics
- Hyperkalemia/metabolism
- Hyperkalemia/physiopathology
- Kidney Tubules, Collecting/drug effects
- Kidney Tubules, Collecting/metabolism
- Kidney Tubules, Collecting/physiopathology
- Kidney Tubules, Distal/drug effects
- Kidney Tubules, Distal/metabolism
- Kidney Tubules, Distal/physiopathology
- Membrane Potentials
- Mice, Knockout
- Natriuresis/drug effects
- Potassium/urine
- Receptor, Angiotensin, Type 1/agonists
- Receptor, Angiotensin, Type 1/metabolism
- Receptors, Mineralocorticoid/deficiency
- Receptors, Mineralocorticoid/genetics
- Renal Elimination/drug effects
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Affiliation(s)
- Peng Wu
- Institute of Hypertension and Kidney DiseaseThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Zhong‐Xiuzi Gao
- Institute of Hypertension and Kidney DiseaseThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Dan‐Dan Zhang
- Department of PharmacologyNew York Medical CollegeValhallaNY
| | - Xin‐Peng Duan
- Department of PharmacologyNew York Medical CollegeValhallaNY
| | - Andrew S. Terker
- Department of MedicineOregon Health & Science UniversityVA Portland Health Care SystemPortlandOR
| | - Dao‐Hong Lin
- Department of PharmacologyNew York Medical CollegeValhallaNY
| | - David H. Ellison
- Department of MedicineOregon Health & Science UniversityVA Portland Health Care SystemPortlandOR
| | - Wen‐Hui Wang
- Department of PharmacologyNew York Medical CollegeValhallaNY
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50
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It takes more than two to tango: mechanosignaling of the endothelial surface. Pflugers Arch 2020; 472:419-433. [PMID: 32239285 PMCID: PMC7165135 DOI: 10.1007/s00424-020-02369-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 03/13/2020] [Accepted: 03/18/2020] [Indexed: 02/07/2023]
Abstract
The endothelial surface is a highly flexible signaling hub which is able to sense the hemodynamic forces of the streaming blood. The subsequent mechanosignaling is basically mediated by specific structures, like the endothelial glycocalyx building the top surface layer of endothelial cells as well as mechanosensitive ion channels within the endothelial plasma membrane. The mechanical properties of the endothelial cell surface are characterized by the dynamics of cytoskeletal proteins and play a key role in the process of signal transmission from the outside (lumen of the blood vessel) to the interior of the cell. Thus, the cell mechanics directly interact with the function of mechanosensitive structures and ion channels. To precisely maintain the vascular tone, a coordinated functional interdependency between endothelial cells and vascular smooth muscle cells is necessary. This is given by the fact that mechanosensitive ion channels are expressed in both cell types and that signals are transmitted via autocrine/paracrine mechanisms from layer to layer. Thus, the outer layer of the endothelial cells can be seen as important functional mechanosensitive and reactive cellular compartment. This review aims to describe the known mechanosensitive structures of the vessel building a bridge between the important role of physiological mechanosignaling and the proper vascular function. Since mutations and dysfunction of mechanosensitive proteins are linked to vascular pathologies such as hypertension, they play a potent role in the field of channelopathies and mechanomedicine.
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