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Daugherty A, Sawada H, Sheppard MB, Lu HS. Angiotensinogen as a Therapeutic Target for Cardiovascular and Metabolic Diseases. Arterioscler Thromb Vasc Biol 2024; 44:1021-1030. [PMID: 38572647 PMCID: PMC11225801 DOI: 10.1161/atvbaha.124.318374] [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] [Indexed: 04/05/2024]
Abstract
AGT (angiotensinogen) is the unique precursor for the generation of all the peptides of the renin-angiotensin system, but it has received relatively scant attention compared to many other renin-angiotensin system components. Focus on AGT has increased recently, particularly with the evolution of drugs to target the synthesis of the protein. AGT is a noninhibitory serpin that has several conserved domains in addition to the angiotensin II sequences at the N terminus. Increased study is needed on the structure-function relationship to resolve many unknowns regarding AGT metabolism. Constitutive whole-body genetic deletion of Agt in mice leads to multiple developmental defects creating a challenge to use these mice for mechanistic studies. This has been overcome by creating Agt-floxed mice to enable the development of cell-specific deficiencies that have provided considerable insight into a range of cardiovascular and associated diseases. This has been augmented by the recent development of pharmacological approaches targeting hepatocytes in humans to promote protracted inhibition of AGT synthesis. Genetic deletion or pharmacological inhibition of Agt has been demonstrated to be beneficial in a spectrum of diseases experimentally, including hypertension, atherosclerosis, aortic and superior mesenteric artery aneurysms, myocardial dysfunction, and hepatic steatosis. This review summarizes the findings of recent studies utilizing AGT manipulation as a therapeutic approach.
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Affiliation(s)
- Alan Daugherty
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY
- Saha Aortic Center, University of Kentucky, Lexington, KY
- Department of Physiology, University of Kentucky, Lexington, KY
| | - Hisashi Sawada
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY
- Saha Aortic Center, University of Kentucky, Lexington, KY
- Department of Physiology, University of Kentucky, Lexington, KY
| | - Mary B. Sheppard
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY
- Saha Aortic Center, University of Kentucky, Lexington, KY
- Department of Physiology, University of Kentucky, Lexington, KY
- Department of Family and Community Medicine, University of Kentucky, Lexington, KY
- Department of Surgery, University of Kentucky, Lexington, KY
| | - Hong S. Lu
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY
- Saha Aortic Center, University of Kentucky, Lexington, KY
- Department of Physiology, University of Kentucky, Lexington, KY
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Dominguez Rieg JA, Rieg T. New functions and roles of the Na +-H +-exchanger NHE3. Pflugers Arch 2024; 476:505-516. [PMID: 38448727 DOI: 10.1007/s00424-024-02938-9] [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: 02/05/2024] [Revised: 02/22/2024] [Accepted: 02/27/2024] [Indexed: 03/08/2024]
Abstract
The sodium/proton exchanger isoform 3 (NHE3) is expressed in the intestine and the kidney, where it contributes to hydrogen secretion and sodium (re)absorption. The roles of this transporter have been studied by the use of the respective knockout mice and by using pharmacological inhibitors. Whole-body NHE3 knockout mice suffer from a high mortality rate (with only ∼30% of mice surviving into adulthood), and based on the expression of NHE3 in both intestine and kidney, some conclusions that were originally derived were based on this rather complex phenotype. In the last decade, more refined models have been developed that added temporal and spatial control of NHE3 expression. For example, novel mouse models have been developed with a knockout of NHE3 in intestinal epithelial cells, tubule/collecting duct of the kidney, proximal tubule of the kidney, and thick ascending limb of the kidney. These refined models have significantly contributed to our understanding of the role of NHE3 in a tissue/cell type-specific manner. In addition, tenapanor was developed, which is a non-absorbable, intestine-specific NHE3 inhibitor. In rat and human studies, tenapanor lowered intestinal Pi uptake and was effective in lowering plasma Pi levels in patients on hemodialysis. Of note, diarrhea is seen as a side effect of tenapanor (with its indication for the treatment of constipation) and in intestine-specific NHE3 knockout mice; however, effects on plasma Pi were not supported by this mouse model which showed enhanced and not reduced intestinal Pi uptake. Further studies indicated that the gut microbiome in mice lacking intestinal NHE3 resembles an intestinal environment favoring the competitive advantage of inflammophilic over anti-inflammatory species, something similar seen in patients with inflammatory bowel disease. This review will highlight recent developments and summarize newly gained insight from these refined models.
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Affiliation(s)
- Jessica A Dominguez Rieg
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
- James A. Haley Veterans' Hospital, Tampa, FL, 33612, USA
- Hypertension and Kidney Research Center, University of South Florida, Tampa, FL, 33602, USA
| | - Timo Rieg
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.
- James A. Haley Veterans' Hospital, Tampa, FL, 33612, USA.
- Hypertension and Kidney Research Center, University of South Florida, Tampa, FL, 33602, USA.
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Huang YC, Liu CJ, Lu ZH, Huang HS. Long-Term Sodium Deficiency Reduces Sodium Excretion but Impairs Renal Function and Increases Stone Formation in Hyperoxaluric Calcium Oxalate Rats. Int J Mol Sci 2024; 25:3942. [PMID: 38612752 PMCID: PMC11011831 DOI: 10.3390/ijms25073942] [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: 02/25/2024] [Revised: 03/19/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024] Open
Abstract
Excessive sodium intake is associated with nephrolithiasis, but the impact of sodium-deficient (SD) diets is unknown. Hence, we investigated the effects of short- and long-term SD diets on the expression of renal aquaporins and sodium transporters, and thus calcium oxalate (CaOx) crystal formation in hyperoxaluria rats. In a short-term sodium balance study, six male rats received drinking water and six received 0.75% ethylene glycol (EG) to induce hyperoxaluria. After a 30-day period of feeding on normal chow, both groups were treated with a normal-sodium diet for 5 days, followed by a sodium-free diet for the next 5 days. In a long-term SD study (42 days), four groups, induced with EG or not, were treated with normal-sodium water and sodium-free drinking water, alternately. Short-term sodium restriction in EG rats reversed the daily positive sodium balance, but progressively caused a negative cumulative water balance. In the long-term study, the abundant levels of of Na/H exchanger, thiazide-sensitive Na-Cl cotransporter, Na-K-ATPase, and aquaporins-1 from SD + EG rats were markedly reduced, corresponding to a decrease in Uosm, as compared to SD rats. Increased urine calcium, AP(CaOx)index, and renal CaOx deposition were also noted in SD + EG rats. Although the SD treatment reduced sodium excretion, it also increased urinary calcium and impaired renal function, ultimately causing the formation of more CaOx crystals.
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Affiliation(s)
| | | | | | - Ho-Shiang Huang
- Department of Urology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704302, Taiwan; (Y.-C.H.); (C.-J.L.); (Z.-H.L.)
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Duan XP, Xiao Y, Su XT, Zheng JY, Gurley S, Emathinger J, Yang CL, McCormick J, Ellison DH, Lin DH, Wang WH. Role of Angiotensin II Type 1a Receptor (AT1aR) of Renal Tubules in Regulating Inwardly Rectifying Potassium Channels 4.2 (Kir4.2), Kir4.1, and Epithelial Na + Channel (ENaC). Hypertension 2024; 81:126-137. [PMID: 37909221 PMCID: PMC10842168 DOI: 10.1161/hypertensionaha.123.21389] [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: 04/19/2023] [Accepted: 10/12/2023] [Indexed: 11/02/2023]
Abstract
BACKGROUND Kir4.2 and Kir4.1 play a role in regulating membrane transport in the proximal tubule (PT) and in the distal-convoluted-tubule (DCT), respectively. METHODS We generated kidney-tubule-specific-AT1aR-knockout (Ks-AT1aR-KO) mice to examine whether renal AT1aR regulates Kir4.2 and Kir4.1. RESULTS Ks-AT1aR-KO mice had a lower systolic blood pressure than Agtr1aflox/flox (control) mice. Ks-AT1aR-KO mice had a lower expression of NHE3 (Na+/H+-exchanger 3) and Kir4.2, a major Kir-channel in PT, than Agtr1aflox/flox mice. Whole-cell recording also demonstrated that the membrane potential in PT of Ks-AT1aR-KO mice was lesser negative than Agtr1aflox/flox mice. The expression of Kir4.1 and Kir5.1, Kir4.1/Kir5.1-mediated K+ currents of DCT and DCT membrane potential in Ks-AT1aR-KO mice, were similar to Agtr1aflox/flox mice. However, angiotensin II perfusion for 7 days hyperpolarized the membrane potential in PT and DCT of the control mice but not in Ks-AT1aR-KO mice, while angiotensin II perfusion did not change the expression of Kir4.1, Kir4.2, and Kir5.1. Deletion of AT1aR did not significantly affect the expression of αENaC (epithelial Na+ channel) and βENaC but increased cleaved γENaC expression. Patch-clamp experiments demonstrated that deletion of AT1aR increased amiloride-sensitive Na+-currents in the cortical-collecting duct but not in late-DCT. However, tertiapin-Q sensitive renal outer medullary potassium channel currents were similar in both genotypes. CONCLUSIONS AT1aR determines the baseline membrane potential of PT by controlling Kir4.2 expression/activity but AT1aR is not required for determining the baseline membrane potential of the DCT and Kir4.1/Kir5.1 activity/expression. However, AT1aR is required for angiotensin II-induced hyperpolarization of basolateral membrane of PT and DCT. Deletion of AT1aR had no effect on baseline renal outer medullary potassium channel activity but increased ENaC activity in the CCD.
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Affiliation(s)
- Xin-Peng Duan
- Department of Physiology, Xuzhou Medical University, Xuzhou, China
- Department of Pharmacology, New York Medical College, Valhalla, NY
| | - Yu Xiao
- Department of Physiology, Qiqihar Medical College, Heilongjiang, China
- Department of Pharmacology, New York Medical College, Valhalla, NY
| | - Xiao-Tong Su
- Department of Medicine, Oregon Health & Science University, Portland, Oregon
| | - Jun-Ya Zheng
- Department of Pharmacology, New York Medical College, Valhalla, NY
| | - Susan Gurley
- Department of Medicine, Oregon Health & Science University, Portland, Oregon
| | | | - Chao-Ling Yang
- Department of Medicine, Oregon Health & Science University, Portland, Oregon
| | - James McCormick
- Department of Medicine, Oregon Health & Science University, Portland, Oregon
| | - David H. Ellison
- Department of Medicine, Oregon Health & Science University, Portland, Oregon
| | - Dao-Hong Lin
- Department of Pharmacology, New York Medical College, Valhalla, NY
| | - Wen-Hui Wang
- Department of Pharmacology, New York Medical College, Valhalla, NY
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Eguchi S, Sparks MA, Sawada H, Lu HS, Daugherty A, Zhuo JL. Recent Advances in Understanding the Molecular Pathophysiology of Angiotensin II Receptors: Lessons From Cell-Selective Receptor Deletion in Mice. Can J Cardiol 2023; 39:1795-1807. [PMID: 37394059 DOI: 10.1016/j.cjca.2023.06.421] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/08/2023] [Accepted: 06/20/2023] [Indexed: 07/04/2023] Open
Abstract
The renin-angiotensin system (RAS) is an essential hormonal system involved in water and sodium reabsorption, renal blood flow regulation, and arterial constriction. Systemic stimulation of the RAS with infusion of the main peptide angiotensin II (Ang II) in animals as well as pathological elevation of renin (ie, renovascular hypertension) to increase circulatory Ang II in humans ultimately lead to hypertension and end organ damage. In addition to hypertension, accumulating evidence supports that the Ang II type 1 receptor exerts a critical role in cardiovascular and kidney diseases independent of blood pressure elevation. In the past 2 decades, the identification of an increased number of peptides and receptors has facilitated the concept that the RAS has detrimental and beneficial effects on the cardiovascular system depending on which RAS components are activated. For example, angiotensin 1-7 and Ang II type 2 receptors act as a counter-regulatory system against the classical RAS by mediating vasodilation. Although the RAS as an endocrine system for regulation of blood pressure is well established, there remain many unanswered questions and controversial findings regarding blood pressure regulation and pathophysiological regulation of cardiovascular diseases at the tissue level. This review article includes the latest knowledge gleaned from cell type-selective gene deleted mice regarding cell type-specific roles of Ang II receptors and their significance in health and diseases are discussed. In particular, we focus on the roles of these receptors expressed in vascular, cardiac, and kidney epithelial cells.
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Affiliation(s)
- Satoru Eguchi
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania, USA.
| | - Matthew A Sparks
- Division of Nephrology, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA; Renal Section, Durham VA Medical Center, Durham, North Carolina, USA
| | - Hisashi Sawada
- Department of Physiology, Saha Cardiovascular Center, and Saha Aortic Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Hong S Lu
- Department of Physiology, Saha Cardiovascular Center, and Saha Aortic Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Alan Daugherty
- Department of Physiology, Saha Cardiovascular Center, and Saha Aortic Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Jia L Zhuo
- Tulane Hypertension and Renal Center of Excellence and Department of Physiology, Tulane University School of Medicine, New Orleans, Louisiana, USA
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Zhao WT, Herrmann KH, Sibgatulin R, Nahardani A, Krämer M, Heitplatz B, van Marck V, Reuter S, Reichenbach JR, Hoerr V. Perfusion and T 2 Relaxation Time as Predictors of Severity and Outcome in Sepsis-Associated Acute Kidney Injury: A Preclinical MRI Study. J Magn Reson Imaging 2023; 58:1954-1963. [PMID: 37026419 DOI: 10.1002/jmri.28698] [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: 07/28/2022] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 04/08/2023] Open
Abstract
BACKGROUND Preventing sepsis-associated acute kidney injury (S-AKI) can be challenging because it develops rapidly and is often asymptomatic. Probability assessment of disease progression for therapeutic follow-up and outcome are important to intervene and prevent further damage. PURPOSE To establish a noninvasive multiparametric MRI (mpMRI) tool, including T1 , T2 , and perfusion mapping, for probability assessment of the outcome of S-AKI. STUDY TYPE Preclinical randomized prospective study. ANIMAL MODEL One hundred and forty adult female SD rats (65 control and 75 sepsis). FIELD STRENGTH/SEQUENCE 9.4T; T1 and perfusion map (FAIR-EPI) and T2 map (multiecho RARE). ASSESSMENT Experiment 1: To identify renal injury in relation to sepsis severity, serum creatinine levels were determined (31 control and 35 sepsis). Experiment 2: Animals underwent mpMRI (T1 , T2 , perfusion) 18 hours postsepsis. A subgroup of animals was immediately sacrificed for histology examination (nine control and seven sepsis). Result of mpMRI in follow-up subgroup (25 control and 33 sepsis) was used to predict survival outcomes at 96 hours. STATISTICAL TESTS Mann-Whitney U test, Spearman/Pearson correlation (r), P < 0.05 was considered statistically significant. RESULTS Severely ill septic animals exhibited significantly increased serum creatinine levels compared to controls (70 ± 30 vs. 34 ± 9 μmol/L, P < 0.0001). Cortical perfusion (480 ± 80 vs. 330 ± 140 mL/100 g tissue/min, P < 0.005), and cortical and medullary T2 relaxation time constants were significantly reduced compared to controls (41 ± 4 vs. 37 ± 5 msec in cortex, P < 0.05, 52 ± 7 vs. 45 ± 6 msec in medulla, P < 0.05). The combination of cortical T2 relaxation time constants and perfusion results at 18 hours could predict survival outcomes at 96 hours with high sensitivity (80%) and specificity (73%) (area under curve of ROC = 0.8, Jmax = 0.52). DATA CONCLUSION This preclinical study suggests combined T2 relaxation time and perfusion mapping as first line diagnostic tool for treatment planning. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE: 2.
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Affiliation(s)
- Wan-Ting Zhao
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
- Institute of Medical Microbiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Karl-Heinz Herrmann
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Renat Sibgatulin
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Ali Nahardani
- Heart Center Bonn, Department of Internal Medicine II, University Hospital Bonn, Bonn, Germany
| | - Martin Krämer
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
- Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Barbara Heitplatz
- Department of Pathology, University Hospital Münster, Münster, Germany
| | - Veerle van Marck
- Department of Pathology, University Hospital Münster, Münster, Germany
| | - Stefan Reuter
- Department of Medicine D, Division of General Internal Medicine, Nephrology and Rheumatology, University Hospital Münster, Münster, Germany
| | - Jürgen R Reichenbach
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Verena Hoerr
- Institute of Medical Microbiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
- Heart Center Bonn, Department of Internal Medicine II, University Hospital Bonn, Bonn, Germany
- Translational Research Imaging Center (TRIC), Clinic of Radiology, University of Münster, Münster, Germany
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Rodrigues AF, Bader M. The contribution of the AT1 receptor to erythropoiesis. Biochem Pharmacol 2023; 217:115805. [PMID: 37714274 DOI: 10.1016/j.bcp.2023.115805] [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: 06/22/2023] [Revised: 09/09/2023] [Accepted: 09/12/2023] [Indexed: 09/17/2023]
Abstract
The renin-angiotensin system (RAS) comprises a broad set of functional peptides and receptors that play a role in cardiovascular homeostasis and contribute to cardiovascular pathologies. Angiotensin II (Ang II) is the most potent peptide hormone produced by the RAS due to its high abundance and its strong and pleiotropic impact on the cardiovascular system. Formation of Ang II takes place in the bloodstream and additionally in tissues in the so-called local RAS. Of the two Ang II receptors (AT1 and AT2) that Ang II binds to, AT1 is the most expressed throughout the mammalian body. AT1 expression is not restricted to cells of the cardiovascular system but in fact AT1 protein is found in nearly all organs, hence, Ang II takes part in several modulatory physiological processes one of which is erythropoiesis. In this review, we present multiple evidence supporting that Ang II modulates physiological and pathological erythropoiesis processes trough the AT1 receptor. Cumulative evidence indicates that Ang II by three distinct mechanisms influences erythropoiesis: 1) stimulation of renal erythropoietin synthesis; 2) direct action on bone marrow precursor cells; and 3) modulation of sympathetic nerve activity to the bone marrow. The text highlights clinical and preclinical evidence focusing on mechanistic studies using rodent models.
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Affiliation(s)
- André F Rodrigues
- Max Delbrück Center (MDC), Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Germany.
| | - Michael Bader
- Max Delbrück Center (MDC), Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Germany; Charité Universitätsmedizin Berlin, Berlin, Germany; Institute for Biology, University of Lübeck, Lübeck, Germany.
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Kukida M, Amioka N, Ye D, Chen H, Moorleghen JJ, Liang CL, Howatt DA, Katsumata Y, Yanagita M, Sawada H, Daugherty A, Lu HS. Manipulation of components of the renin angiotensin system in renal proximal tubules fails to alter atherosclerosis in hypercholesterolemic mice. Front Cardiovasc Med 2023; 10:1250234. [PMID: 37655218 PMCID: PMC10466789 DOI: 10.3389/fcvm.2023.1250234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 08/03/2023] [Indexed: 09/02/2023] Open
Abstract
Background and objective Whole body manipulation of the renin-angiotensin system (RAS) consistently exerts profound effects on experimental atherosclerosis development. A deficit in the literature has been a lack of attention to the effects of sex. Also, based on data with gene-deleted mice, the site of RAS activity that influences lesion formation is at an unknown distant location. Since angiotensin (AngII) concentrations are high in kidney and the major components of the RAS are present in renal proximal tubule cells (PTCs), this study evaluated the role of the RAS in PTCs in atherosclerosis development. Methods and results Mice with an LDL receptor -/- background were fed Western diet to induce hypercholesterolemia and atherosclerosis. We first demonstrated the role of AT1 receptor antagonism on atherosclerosis in both sexes. Losartan, an AngII type 1 (AT1) receptor blocker, had greater blood pressure-lowering effects in females than males, but equivalent effects between sexes in reducing atherosclerotic lesion size. To determine the roles of renal AT1a receptor and angiotensin-converting enzyme (ACE), either component was deleted in PTCs after weaning using a tamoxifen-inducible Cre expressed under the control of an Ndrg1 promoter. Despite profound deletion of AT1a receptor or ACE in PTCs, the absence of either protein did not influence development of atherosclerosis in either sex. Conversely, mice expressing human angiotensinogen and renin in PTCs or expressing human angiotensinogen in liver but human renin in PTCs did not change atherosclerotic lesion size in male mice. Conclusion Whole-body AT1R inhibition reduced atherosclerosis equivalently in both male and female mice; however, PTC-specific manipulation of the RAS components had no effects on hypercholesterolemia-induced atherosclerosis.
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Affiliation(s)
- Masayoshi Kukida
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
| | - Naofumi Amioka
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
| | - Dien Ye
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
| | - Hui Chen
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
| | - Jessica J. Moorleghen
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
| | - Ching-Ling Liang
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
| | - Deborah A. Howatt
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
| | - Yuriko Katsumata
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, United States
- Department of Biostatistics, University of Kentucky, Lexington, KY, United States
| | - Motoko Yanagita
- Department of Nephrology, Kyoto University Graduate School of Medicine, Kyoto, Japan
- Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, Japan
| | - Hisashi Sawada
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
- Saha Aortic Center, University of Kentucky, Lexington, KY, United States
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Alan Daugherty
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
- Saha Aortic Center, University of Kentucky, Lexington, KY, United States
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Hong S. Lu
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States
- Saha Aortic Center, University of Kentucky, Lexington, KY, United States
- Department of Physiology, University of Kentucky, Lexington, KY, United States
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9
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Shoemaker R, Poglitsch M, Huang H, Vignes K, Srinivasan A, Cockerham C, Schadler A, Bauer JA, O’Brien JM. Activation of the Renin-Angiotensin-Aldosterone System Is Attenuated in Hypertensive Compared with Normotensive Pregnancy. Int J Mol Sci 2023; 24:12728. [PMID: 37628909 PMCID: PMC10454898 DOI: 10.3390/ijms241612728] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/04/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Hypertension during pregnancy increases the risk of adverse maternal and fetal outcomes, but the mechanisms of pregnancy hypertension are not precisely understood. Elevated plasma renin activity and aldosterone concentrations play an important role in the normal physiologic adaptation to pregnancy. These effectors are reduced in patients with pregnancy hypertension, creating an opportunity to define the features of the renin-angiotensin-aldosterone system (RAAS) that are characteristic of this disorder. In the current study, we used a novel LC-MS/MS-based methodology to develop comprehensive profiles of RAAS peptides and effectors over gestation in a cohort of 74 pregnant women followed prospectively for the development of gestational hypertension and pre-eclampsia (HYP, 27 patients) versus those remaining normotensive (NT, 47 patients). In NT pregnancy, the plasma renin activity surrogate, (PRA-S, calculated from the sum of Angiotensin I + Angiotensin II) and aldosterone concentrations significantly increased from the first to the third trimester, accompanied by a modest increase in the concentrations of angiotensin peptide metabolites. In contrast, in HYP pregnancies, PRA-S and angiotensin peptides were largely unchanged over gestation, and third-trimester aldosterone concentrations were significantly lower compared with those in NT pregnancies. The results indicated that the predominant features of pregnancies that develop HYP are stalled or waning activation of the RAAS in the second half of pregnancy (accompanied by unchanging levels of angiotensin peptides) and the attenuated secretion of aldosterone.
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Affiliation(s)
- Robin Shoemaker
- Department of Dietetics and Human Nutrition, University of Kentucky, Lexington, KY 40506, USA
| | | | - Hong Huang
- Department of Pediatrics, University of Kentucky, Lexington, KY 40536, USA
| | - Katherine Vignes
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY 40506, USA
| | - Aarthi Srinivasan
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY 40506, USA
| | - Cynthia Cockerham
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY 40506, USA
| | - Aric Schadler
- Department of Pediatrics, University of Kentucky, Lexington, KY 40536, USA
| | - John A. Bauer
- Department of Pediatrics, University of Kentucky, Lexington, KY 40536, USA
| | - John M. O’Brien
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY 40506, USA
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10
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Nwia SM, Leite APO, Li XC, Zhuo JL. Sex differences in the renin-angiotensin-aldosterone system and its roles in hypertension, cardiovascular, and kidney diseases. Front Cardiovasc Med 2023; 10:1198090. [PMID: 37404743 PMCID: PMC10315499 DOI: 10.3389/fcvm.2023.1198090] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 06/06/2023] [Indexed: 07/06/2023] Open
Abstract
Cardiovascular disease is a pathology that exhibits well-researched biological sex differences, making it possible for physicians to tailor preventative and therapeutic approaches for various diseases. Hypertension, which is defined as blood pressure greater than 130/80 mmHg, is the primary risk factor for developing coronary artery disease, stroke, and renal failure. Approximately 48% of American men and 43% of American women suffer from hypertension. Epidemiological data suggests that during reproductive years, women have much lower rates of hypertension than men. However, this protective effect disappears after the onset of menopause. Treatment-resistant hypertension affects approximately 10.3 million US adults and is unable to be controlled even after implementing ≥3 antihypertensives with complementary mechanisms. This indicates that other mechanisms responsible for modulating blood pressure are still unclear. Understanding the differences in genetic and hormonal mechanisms that lead to hypertension would allow for sex-specific treatment and an opportunity to improve patient outcomes. Therefore, this invited review will review and discuss recent advances in studying the sex-specific physiological mechanisms that affect the renin-angiotensin system and contribute to blood pressure control. It will also discuss research on sex differences in hypertension management, treatment, and outcomes.
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Affiliation(s)
- Sarah M. Nwia
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Ana Paula O. Leite
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Xiao Chun Li
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Jia Long Zhuo
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
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Li X, Zhuo J. Intracellular Angiotensin II Stimulation of Sodium Transporter Expression in Proximal Tubule Cells via AT 1 (AT 1a) Receptor-Mediated, MAP Kinases ERK1/2- and NF-кB-Dependent Signaling Pathways. Cells 2023; 12:1492. [PMID: 37296613 PMCID: PMC10252550 DOI: 10.3390/cells12111492] [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: 03/17/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
The current prevailing paradigm in the renin-angiotensin system dictates that most, if not all, biological, physiological, and pathological responses to its most potent peptide, angiotensin II (Ang II), are mediated by extracellular Ang II activating its cell surface receptors. Whether intracellular (or intracrine) Ang II and its receptors are involved remains incompletely understood. The present study tested the hypothesis that extracellular Ang II is taken up by the proximal tubules of the kidney by an AT1 (AT1a) receptor-dependent mechanism and that overexpression of an intracellular Ang II fusion protein (ECFP/Ang II) in mouse proximal tubule cells (mPTC) stimulates the expression of Na+/H+ exchanger 3 (NHE3), Na+/HCO3- cotransporter, and sodium and glucose cotransporter 2 (Sglt2) by AT1a/MAPK/ERK1/2/NF-kB signaling pathways. mPCT cells derived from male wild-type and type 1a Ang II receptor-deficient mice (Agtr1a-/-) were transfected with an intracellular enhanced cyan fluorescent protein-tagged Ang II fusion protein, ECFP/Ang II, and treated without or with AT1 receptor blocker losartan, AT2 receptor blocker PD123319, MEK1/MEK2 inhibitor U0126, NF-кB inhibitor RO 106-9920, or p38 MAP kinase inhibitor SB202196, respectively. In wild-type mPCT cells, the expression of ECFP/Ang II significantly increased NHE3, Na+/HCO3-, and Sglt2 expression (p < 0.01). These responses were accompanied by >3-fold increases in the expression of phospho-ERK1/2 and the p65 subunit of NF-кB (p < 0.01). Losartan, U0126, or RO 106-9920 all significantly attenuated ECFP/Ang II-induced NHE3 and Na+/HCO3- expression (p < 0.01). Deletion of AT1 (AT1a) receptors in mPCT cells attenuated ECFP/Ang II-induced NHE3 and Na+/HCO3- expression (p < 0.01). Interestingly, the AT2 receptor blocker PD123319 also attenuated ECFP/Ang II-induced NHE3 and Na+/HCO3- expression (p < 0.01). These results suggest that, similar to extracellular Ang II, intracellular Ang II may also play an important role in Ang II receptor-mediated proximal tubule NHE3, Na+/HCO3-, and Sglt2 expression by activation of AT1a/MAPK/ERK1/2/NF-kB signaling pathways.
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Affiliation(s)
- Xiaochun Li
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA;
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA
| | - Jialong Zhuo
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA;
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA
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12
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Renal sympathetic activity: A key modulator of pressure natriuresis in hypertension. Biochem Pharmacol 2023; 208:115386. [PMID: 36535529 DOI: 10.1016/j.bcp.2022.115386] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 12/11/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
Hypertension is a complex disorder ensuing necessarily from alterations in the pressure-natriuresis relationship, the main determinant of long-term control of blood pressure. This mechanism sets natriuresis to the level of blood pressure, so that increasing pressure translates into higher osmotically driven diuresis to reduce volemia and control blood pressure. External factors affecting the renal handling of sodium regulate the pressure-natriuresis relationship so that more or less natriuresis is attained for each level of blood pressure. Hypertension can thus only develop following primary alterations in the pressure to natriuresis balance, or by abnormal activity of the regulation network. On the other hand, increased sympathetic tone is a very frequent finding in most forms of hypertension, long regarded as a key element in the pathophysiological scenario. In this article, we critically analyze the interplay of the renal component of the sympathetic nervous system and the pressure-natriuresis mechanism in the development of hypertension. A special focus is placed on discussing recent findings supporting a role of baroreceptors as a component, along with the afference of reno-renal reflex, of the input to the nucleus tractus solitarius, the central structure governing the long-term regulation of renal sympathetic efferent tone.
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Li XC, Hassan R, Leite APO, Katsurada A, Dugas C, Sato R, Zhuo JL. Genetic Deletion of AT 1a Receptor or Na +/H + Exchanger 3 Selectively in the Proximal Tubules of the Kidney Attenuates Two-Kidney, One-Clip Goldblatt Hypertension in Mice. Int J Mol Sci 2022; 23:ijms232415798. [PMID: 36555438 PMCID: PMC9779213 DOI: 10.3390/ijms232415798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/30/2022] [Accepted: 12/06/2022] [Indexed: 12/14/2022] Open
Abstract
The roles of angiotensin II (Ang II) AT1 (AT1a) receptors and its downstream target Na+/H+ exchanger 3 (NHE3) in the proximal tubules in the development of two-kidney, 1-clip (2K1C) Goldblatt hypertension have not been investigated previously. The present study tested the hypothesis that deletion of the AT1a receptor or NHE3 selectively in the proximal tubules of the kidney attenuates the development of 2K1C hypertension using novel mouse models with proximal tubule-specific deletion of AT1a receptors or NHE3. 2K1C Goldblatt hypertension was induced by placing a silver clip (0.12 mm) on the left renal artery for 4 weeks in adult male wild-type (WT), global Agtr1a−/−, proximal tubule (PT)-specific PT-Agtr1a−/− or PT-Nhe3−/− mice, respectively. As expected, telemetry blood pressure increased in a time-dependent manner in WT mice, reaching a maximal response by Week 3 (p < 0.01). 2K1C hypertension in WT mice was associated with increases in renin expression in the clipped kidney and decreases in the nonclipped kidney (p < 0.05). Plasma and kidney Ang II were significantly increased in WT mice with 2K1C hypertension (p < 0.05). Tubulointerstitial fibrotic responses were significantly increased in the clipped kidney (p < 0.01). Whole-body deletion of AT1a receptors completely blocked the development of 2K1C hypertension in Agtr1a−/− mice (p < 0.01 vs. WT). Likewise, proximal tubule-specific deletion of Agtr1a in PT-Agtr1a−/− mice or NHE3 in PT-Nhe3−/− mice also blocked the development of 2K1C hypertension (p < 0.01 vs. WT). Taken together, the present study provides new evidence for a critical role of proximal tubule Ang II/AT1 (AT1a)/NHE3 axis in the development of 2K1C Goldblatt hypertension.
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Affiliation(s)
- Xiao Chun Li
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA
| | - Rumana Hassan
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA
| | - Ana Paula O. Leite
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA
| | - Akemi Katsurada
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA
| | - Courtney Dugas
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA
| | - Ryosuke Sato
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA
| | - Jia Long Zhuo
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA
- Correspondence: ; Tel.: +1-504-988-4363; Fax: +1-504-988-2675
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Kim CW, Young Kim J, Lee S, Kim I. Dahl salt-resistant rats are protected against angiotensin II-induced hypertension. Biochem Pharmacol 2022; 203:115193. [DOI: 10.1016/j.bcp.2022.115193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 11/16/2022]
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Ohara H, Nabika T. Genetic Modifications to Alter Blood Pressure Level. Biomedicines 2022; 10:biomedicines10081855. [PMID: 36009402 PMCID: PMC9405136 DOI: 10.3390/biomedicines10081855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/27/2022] [Accepted: 07/29/2022] [Indexed: 12/04/2022] Open
Abstract
Genetic manipulation is one of the indispensable techniques to examine gene functions both in vitro and in vivo. In particular, cardiovascular phenotypes such as blood pressure cannot be evaluated in vitro system, necessitating the creation of transgenic or gene-targeted knock-out and knock-in experimental animals to understand the pathophysiological roles of specific genes on the disease conditions. Although genome-wide association studies (GWAS) in various human populations have identified multiple genetic variations associated with increased risk for hypertension and/or its complications, the causal links remain unresolved. Genome-editing technologies can be applied to many different types of cells and organisms for creation of knock-out/knock-in models. In the post-GWAS era, it may be more worthwhile to validate pathophysiological implications of the risk variants and/or candidate genes by creating genome-edited organisms.
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Lin H, Geurts F, Hassler L, Batlle D, Mirabito Colafella KM, Denton KM, Zhuo JL, Li XC, Ramkumar N, Koizumi M, Matsusaka T, Nishiyama A, Hoogduijn MJ, Hoorn EJ, Danser AHJ. Kidney Angiotensin in Cardiovascular Disease: Formation and Drug Targeting. Pharmacol Rev 2022; 74:462-505. [PMID: 35710133 PMCID: PMC9553117 DOI: 10.1124/pharmrev.120.000236] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The concept of local formation of angiotensin II in the kidney has changed over the last 10-15 years. Local synthesis of angiotensinogen in the proximal tubule has been proposed, combined with prorenin synthesis in the collecting duct. Binding of prorenin via the so-called (pro)renin receptor has been introduced, as well as megalin-mediated uptake of filtered plasma-derived renin-angiotensin system (RAS) components. Moreover, angiotensin metabolites other than angiotensin II [notably angiotensin-(1-7)] exist, and angiotensins exert their effects via three different receptors, of which angiotensin II type 2 and Mas receptors are considered renoprotective, possibly in a sex-specific manner, whereas angiotensin II type 1 (AT1) receptors are believed to be deleterious. Additionally, internalized angiotensin II may stimulate intracellular receptors. Angiotensin-converting enzyme 2 (ACE2) not only generates angiotensin-(1-7) but also acts as coronavirus receptor. Multiple, if not all, cardiovascular diseases involve the kidney RAS, with renal AT1 receptors often being claimed to exert a crucial role. Urinary RAS component levels, depending on filtration, reabsorption, and local release, are believed to reflect renal RAS activity. Finally, both existing drugs (RAS inhibitors, cyclooxygenase inhibitors) and novel drugs (angiotensin receptor/neprilysin inhibitors, sodium-glucose cotransporter-2 inhibitors, soluble ACE2) affect renal angiotensin formation, thereby displaying cardiovascular efficacy. Particular in the case of the latter three, an important question is to what degree they induce renoprotection (e.g., in a renal RAS-dependent manner). This review provides a unifying view, explaining not only how kidney angiotensin formation occurs and how it is affected by drugs but also why drugs are renoprotective when altering the renal RAS. SIGNIFICANCE STATEMENT: Angiotensin formation in the kidney is widely accepted but little understood, and multiple, often contrasting concepts have been put forward over the last two decades. This paper offers a unifying view, simultaneously explaining how existing and novel drugs exert renoprotection by interfering with kidney angiotensin formation.
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Affiliation(s)
- Hui Lin
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Frank Geurts
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Luise Hassler
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Daniel Batlle
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Katrina M Mirabito Colafella
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Kate M Denton
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Jia L Zhuo
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Xiao C Li
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Nirupama Ramkumar
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Masahiro Koizumi
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Taiji Matsusaka
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Akira Nishiyama
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Martin J Hoogduijn
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Ewout J Hoorn
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - A H Jan Danser
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
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17
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Nwia SM, Li XC, Leite APDO, Hassan R, Zhuo JL. The Na +/H + Exchanger 3 in the Intestines and the Proximal Tubule of the Kidney: Localization, Physiological Function, and Key Roles in Angiotensin II-Induced Hypertension. Front Physiol 2022; 13:861659. [PMID: 35514347 PMCID: PMC9062697 DOI: 10.3389/fphys.2022.861659] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/25/2022] [Indexed: 01/29/2023] Open
Abstract
The sodium (Na+)/hydrogen (H+) exchanger 3 (NHE3) is one of the most important Na+/H+ antiporters in the small intestines of the gastrointestinal tract and the proximal tubules of the kidney. The roles of NHE3 in the regulation of intracellular pH and acid-base balance have been well established in cellular physiology using in vitro techniques. Localized primarily on the apical membranes in small intestines and proximal tubules, the key action of NHE3 is to facilitate the entry of luminal Na+ and the extrusion of intracellular H+ from intestinal and proximal tubule tubular epithelial cells. NHE3 is, directly and indirectly, responsible for absorbing the majority of ingested Na+ from small and large intestines and reabsorbing >50% of filtered Na+ in the proximal tubules of the kidney. However, the roles of NHE3 in the regulation of proximal tubular Na+ transport in the integrative physiological settings and its contributions to the basal blood pressure regulation and angiotensin II (Ang II)-induced hypertension have not been well studied previously due to the lack of suitable animal models. Recently, novel genetically modified mouse models with whole-body, kidney-specific, or proximal tubule-specific deletion of NHE3 have been generated by us and others to determine the critical roles and underlying mechanisms of NHE3 in maintaining basal body salt and fluid balance, blood pressure homeostasis, and the development of Ang II-induced hypertension at the whole-body, kidney, or proximal tubule levels. The objective of this invited article is to review, update, and discuss recent findings on the critical roles of intestinal and proximal tubule NHE3 in maintaining basal blood pressure homeostasis and their potential therapeutic implications in the development of angiotensin II (Ang II)-dependent hypertension.
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Affiliation(s)
- Sarah M. Nwia
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Xiao Chun Li
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Ana Paula de Oliveira Leite
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Rumana Hassan
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Jia Long Zhuo
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States,*Correspondence: Jia Long Zhuo,
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18
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Leite APDO, Li XC, Nwia SM, Hassan R, Zhuo JL. Angiotensin II and AT 1a Receptors in the Proximal Tubules of the Kidney: New Roles in Blood Pressure Control and Hypertension. Int J Mol Sci 2022; 23:ijms23052402. [PMID: 35269547 PMCID: PMC8910592 DOI: 10.3390/ijms23052402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 02/01/2023] Open
Abstract
Contrary to public perception, hypertension remains one of the most important public health problems in the United States, affecting 46% of adults with increased risk for heart attack, stroke, and kidney diseases. The mechanisms underlying poorly controlled hypertension remain incompletely understood. Recent development in the Cre/LoxP approach to study gain or loss of function of a particular gene has significantly helped advance our new insights into the role of proximal tubule angiotensin II (Ang II) and its AT1 (AT1a) receptors in basal blood pressure control and the development of Ang II-induced hypertension. This novel approach has provided us and others with an important tool to generate novel mouse models with proximal tubule-specific loss (deletion) or gain of the function (overexpression). The objective of this invited review article is to review and discuss recent findings using novel genetically modifying proximal tubule-specific mouse models. These new studies have consistently demonstrated that deletion of AT1 (AT1a) receptors or its direct downstream target Na+/H+ exchanger 3 (NHE3) selectively in the proximal tubules of the kidney lowers basal blood pressure, increases the pressure-natriuresis response, and induces natriuretic responses, whereas overexpression of an intracellular Ang II fusion protein or AT1 (AT1a) receptors selectively in the proximal tubules increases proximal tubule Na+ reabsorption, impairs the pressure-natriuresis response, and elevates blood pressure. Furthermore, the development of Ang II-induced hypertension by systemic Ang II infusion or by proximal tubule-specific overexpression of an intracellular Ang II fusion protein was attenuated in mutant mice with proximal tubule-specific deletion of AT1 (AT1a) receptors or NHE3. Thus, these recent studies provide evidence for and new insights into the important roles of intratubular Ang II via AT1 (AT1a) receptors and NHE3 in the proximal tubules in maintaining basal blood pressure homeostasis and the development of Ang II-induced hypertension.
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Affiliation(s)
- Ana Paula de Oliveira Leite
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Xiao C. Li
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Sarah M. Nwia
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Rumana Hassan
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Jia L. Zhuo
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Correspondence: ; Tel.: +1-(504)-988-4363; Fax: +1-(504)-988-2675
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19
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Li XC, Wang CH, Leite APO, Zhuo JL. Intratubular, Intracellular, and Mitochondrial Angiotensin II/AT 1 (AT1a) Receptor/NHE3 Signaling Plays a Critical Role in Angiotensin II-Induced Hypertension and Kidney Injury. Front Physiol 2021; 12:702797. [PMID: 34408663 PMCID: PMC8364949 DOI: 10.3389/fphys.2021.702797] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 05/24/2021] [Indexed: 12/14/2022] Open
Abstract
Hypertension is well recognized to be the most important risk factor for cardiovascular diseases, stroke, and end-stage kidney failure. A quarter of the world’s adult populations and 46% of the US adults develop hypertension and currently require antihypertensive treatments. Only 50% of hypertensive patients are responsive to current antihypertensive drugs, whereas remaining patients may continue to develop cardiovascular, stroke, and kidney diseases. The mechanisms underlying the poorly controlled hypertension remain incompletely understood. Recently, we have focused our efforts to uncover additional renal mechanisms, pathways, and therapeutic targets of poorly controlled hypertension and target organ injury using novel animal models or innovative experimental approaches. Specifically, we studied and elucidated the important roles of intratubular, intracellular, and mitochondrial angiotensin II (Ang II) system in the development of Ang II-dependent hypertension. The objectives of this invited article are to review and discuss our recent findings that (a) circulating and intratubular Ang II is taken up by the proximal tubules via the (AT1) AT1a receptor-dependent mechanism, (b) intracellular administration of Ang II in proximal tubule cells or adenovirus-mediated overexpression of an intracellular Ang II fusion protein selectively in the mitochonria of the proximal tubules induces blood pressure responses, and (c) genetic deletion of AT1 (AT1a) receptors or the Na+/H+ exchanger 3 selectively in the proximal tubules decreases basal blood pressure and attenuates Ang II-induced hypertension. These studies provide a new perspective into the important roles of the intratubular, intracellular, and mitochondrial angiotensin II/AT1 (AT1a) receptor signaling in Ang II-dependent hypertensive kidney diseases.
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Affiliation(s)
- Xiao Chun Li
- Tulane Hypertension and Renal Center of Excellence, Department of Physiology, Tulane University School of Medicine,New Orleans, LA, United States
| | - Chih-Hong Wang
- Tulane Hypertension and Renal Center of Excellence, Department of Physiology, Tulane University School of Medicine,New Orleans, LA, United States
| | - Ana Paula Oliveira Leite
- Tulane Hypertension and Renal Center of Excellence, Department of Physiology, Tulane University School of Medicine,New Orleans, LA, United States
| | - Jia Long Zhuo
- Tulane Hypertension and Renal Center of Excellence, Department of Physiology, Tulane University School of Medicine,New Orleans, LA, United States
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20
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New Insights into the Critical Importance of Intratubular Na +/H + Exchanger 3 and Its Potential Therapeutic Implications in Hypertension. Curr Hypertens Rep 2021; 23:34. [PMID: 34110521 DOI: 10.1007/s11906-021-01152-7] [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] [Accepted: 05/17/2021] [Indexed: 01/08/2023]
Abstract
PURPOSE OF REVIEW The sodium (Na+) and hydrogen (H+) exchanger 3 (NHE3), known as solute carrier family 9 member 3 (SLC9A3), mediates active transcellular Na+ and bicarbonate reabsorption in the small intestine of the gut and proximal tubules of the kidney. The purpose of this article is to review and discuss recent findings on the critical roles of intestinal and proximal tubule NHE3 in maintaining basal blood pressure (BP) homeostasis and their potential therapeutic implications in the development of angiotensin II (Ang II)-dependent hypertension. RECENT FINDINGS Recently, our and other laboratories have generated or used novel genetically modified mouse models with whole-body, kidney-specific, or proximal tubule-specific deletion of NHE3 to determine the critical roles and underlying mechanisms of NHE3 in maintaining basal BP homeostasis and the development of Ang II-induced hypertension at the whole-body, kidney, or proximal tubule levels. The new findings demonstrate that NHE3 contributes to about 10 to 15 mmHg to basal blood pressure levels, and that deletion of NHE3 at the whole-kidney or proximal tubule level, or pharmacological inhibition of NHE3 at the kidney level with an orally absorbable NHE3 inhibitor AVE-0657, attenuates ~ 50% of Ang II-induced hypertension in mice. The results support the proof-of-concept hypothesis that NHE3 plays critical roles in physiologically maintaining normal BP and in the development of Ang II-dependent hypertension. Our results also strongly suggest that NHE3 in the proximal tubules of the kidney may be therapeutically targeted to treat poorly controlled hypertension in humans.
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