1
|
Chen C, Zhong W, Zheng H, Dai G, Zhao W, Wang Y, Dong Q, Shen B. The role of uromodulin in cardiovascular disease: a review. Front Cardiovasc Med 2024; 11:1417593. [PMID: 39049957 PMCID: PMC11267628 DOI: 10.3389/fcvm.2024.1417593] [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: 04/15/2024] [Accepted: 06/25/2024] [Indexed: 07/27/2024] Open
Abstract
Uromodulin, also referred to as Tamm Horsfall protein (THP), is a renal protein exclusively synthesized by the kidneys and represents the predominant urinary protein under normal physiological conditions. It assumes a pivotal role within the renal system, contributing not only to ion transport and immune modulation but also serving as a critical factor in the prevention of urinary tract infections and kidney stone formation. Emerging evidence indicates that uromodulin may serve as a potential biomarker extending beyond renal function. Recent clinical investigations and Mendelian randomization studies have unveiled a discernible association between urinary regulatory protein levels and cardiovascular events and mortality. This review primarily delineates the intricate relationship between uromodulin and cardiovascular disease, elucidates its predictive utility as a novel biomarker for cardiovascular events, and delves into its involvement in various physiological and pathophysiological facets of the cardiovascular system, incorporating recent advancements in corresponding genetics.
Collapse
Affiliation(s)
- Chengqian Chen
- Department of Cardiology Center, The First Hospital of Jilin University, Changchun, China
| | - Wentao Zhong
- Department of Endocrinology and Metabolism, The First Hospital of Jilin University, Changchun, China
| | - Hao Zheng
- Department of Endocrinology and Metabolism, The First Hospital of Jilin University, Changchun, China
| | - Gaoying Dai
- Department of Cardiology Center, The First Hospital of Jilin University, Changchun, China
| | - Wei Zhao
- Department of Cardiology Center, The First Hospital of Jilin University, Changchun, China
| | - Yushi Wang
- Department of Cardiology Center, The First Hospital of Jilin University, Changchun, China
| | - Qi Dong
- Department of Cardiology Center, The First Hospital of Jilin University, Changchun, China
| | - Botao Shen
- Department of Cardiology Center, The First Hospital of Jilin University, Changchun, China
| |
Collapse
|
2
|
Karagiannidis AG, Theodorakopoulou MP, Pella E, Sarafidis PA, Ortiz A. Uromodulin biology. Nephrol Dial Transplant 2024; 39:1073-1087. [PMID: 38211973 PMCID: PMC11210992 DOI: 10.1093/ndt/gfae008] [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: 08/30/2023] [Indexed: 01/13/2024] Open
Abstract
Uromodulin is a kidney-specific glycoprotein which is exclusively produced by the epithelial cells lining the thick ascending limb and early distal convoluted tubule. It is currently recognized as a multifaceted player in kidney physiology and disease, with discrete roles for intracellular, urinary, interstitial and serum uromodulin. Among these, uromodulin modulates renal sodium handling through the regulation of tubular sodium transporters that reabsorb sodium and are targeted by diuretics, such as the loop diuretic-sensitive Na+-K+-2Cl- cotransporter type 2 (NKCC2) and the thiazide-sensitive Na+/Cl- cotransporter (NCC). Given these roles, the contribution of uromodulin to sodium-sensitive hypertension has been proposed. However, recent studies in humans suggest a more complex interaction between dietary sodium intake, uromodulin and blood pressure. This review presents an updated overview of the uromodulin's biology and its various roles, and focuses on the interaction between uromodulin and sodium-sensitive hypertension.
Collapse
Affiliation(s)
- Artemios G Karagiannidis
- First Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Marieta P Theodorakopoulou
- First Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Eva Pella
- First Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Pantelis A Sarafidis
- First Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Alberto Ortiz
- Department of Nephrology and Hypertension, IIS-Fundacion Jimenez Diaz UAM, Madrid, Spain
| |
Collapse
|
3
|
Hao S, DelliPizzi A, Lasaracina AP, Ferreri NR. TNF inhibits AQP2 expression via a miR137-dependent pathway. Am J Physiol Renal Physiol 2024; 326:F152-F164. [PMID: 37969102 PMCID: PMC11198993 DOI: 10.1152/ajprenal.00210.2023] [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: 07/20/2023] [Revised: 10/23/2023] [Accepted: 11/08/2023] [Indexed: 11/17/2023] Open
Abstract
As miR-137 is a regulator of aquaporin (AQP)2 expression and tumor necrosis factor (TNF) inhibits the expression of several extrarenal AQPs, we tested the hypothesis that TNF inhibits AQP2 in the kidney via a miR-137-dependent mechanism. AQP2 mRNA and protein expression decreased ∼70% and 53%, respectively, in primary renal inner medullary collecting duct (IMCD) cells transfected with a miRNA mimic of mmu-miR-137, suggesting that miR-137 directly targets AQP2 mRNA in these cells. Exposure of IMCD cells for 2 h to 400 mosmol/kgH2O medium increased mmu-miR-137 mRNA expression about twofold, conditions that also increased TNF production approximately fourfold. To determine if the increase in mmu-miR-137 mRNA expression was related to the concomitant increase in TNF, IMCD cells were transfected with a lentivirus construct to silence TNF. This construct decreased mmu-miR-137 mRNA expression by ∼63%, suggesting that TNF upregulates the expression of miR-137. Levels of miR-137 also increased approximately twofold in IMCD tubules isolated from male mice given 1% NaCl in the drinking water for 3 days. Intrarenal lentivirus silencing of TNF increased AQP2 mRNA levels and protein expression concomitant with a decrease in miR-137 levels in tubules isolated from mice given NaCl. The changes in AQP2 expression levels affected the diluting ability of the kidney, which was assessed by measuring urine osmolality and urine volume, as the decrease in these parameters after renal silencing of TNF was prevented on intrarenal administration of miR-137. The study reveals a novel TNF function via a miR-137-dependent mechanism that regulates AQP2 expression and function.NEW & NOTEWORTHY An emerging intratubular tumor necrosis factor system, functioning during normotensive noninflammatory conditions, acts as a breaking mechanism that attenuates both the increases in Na+-K+-2Cl- cotransporter and aquaporin-2 induced by arginine vasopressin, thereby contributing to the regulation of electrolyte balance and blood pressure. A greater appreciation for the role of cytokines as mediators of immunophysiological responses may help reveal the relationship between the immune system and other physiological systems.
Collapse
Affiliation(s)
- Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla, New York, United States
| | - AnnMarie DelliPizzi
- Department of Biology, Dominican University New York, Orangeburg, New York, United States
| | - Anna Pia Lasaracina
- Department of Pharmacology, New York Medical College, Valhalla, New York, United States
| | - Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, New York, United States
| |
Collapse
|
4
|
Drugge ED, Farhan K, Zhao H, Abramov R, Graham LA, Stambler N, Hao S, Ferreri NR. Sex and race differences in urinary Tumor Necrosis Factor-α (TNF-α) levels: Secondary analysis of the DASH-sodium trial. J Hum Hypertens 2023; 37:701-708. [PMID: 36008598 DOI: 10.1038/s41371-022-00748-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 07/25/2022] [Accepted: 08/11/2022] [Indexed: 11/09/2022]
Abstract
Previous work in mouse models shows that urinary TNF-α levels become elevated when dietary salt (NaCl) intake increases. To examine if this relationship exists in humans, we conducted a secondary analysis of the Dietary Approaches to Stop Hypertension (DASH)-Sodium trial to determine levels of urinary TNF-α in 367 subjects categorized by race, sex, and blood pressure. The DASH-Sodium trial is a multicenter feeding trial in which subjects were randomly assigned to either the DASH or control diet, and high, medium, and low sodium in random order. Multivariable linear regression was used to model baseline TNF-α and a mixed model was used to model TNF-α as a function of dietary intervention. At baseline, with all subjects on a "typical American diet", urinary TNF-α levels were lowest in Black, p = 0.002 and male subjects, p < 0.001. After randomization to either the DASH or control diet, with increasing levels of sodium, urinary TNF-α levels increased only in subjects on the control diet, p < 0.05. As in the baseline analysis, TNF-α levels were highest in White females, then White males, Black females and lowest in Black males. The results indicate that urinary TNF-α levels in DASH-Sodium subjects are regulated by NaCl intake, modulated by the DASH diet, and influenced by both race and sex. The inherent differences between subgroups support studies in mice showing that increases in renal TNF-α minimize the extent salt-dependent activation of NKCC2.
Collapse
Affiliation(s)
- Elizabeth D Drugge
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA
| | - Khalid Farhan
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA
| | - Hong Zhao
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA
| | - Rozalia Abramov
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA
| | - Lesley A Graham
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA
| | - Nancy Stambler
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA
| | - Shoujin Hao
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA
| | - Nicholas R Ferreri
- Departments of Pharmacology and Public Health, Epidemiology Division, New York Medical College, Valhalla, NY, 10595, USA.
| |
Collapse
|
5
|
Hao S, Zhao H, Hao DH, Ferreri NR. MicroRNA-195a-5p Regulates Blood Pressure by Inhibiting NKCC2A. Hypertension 2023; 80:426-439. [PMID: 36448465 PMCID: PMC9852070 DOI: 10.1161/hypertensionaha.122.19794] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 11/15/2022] [Indexed: 12/05/2022]
Abstract
BACKGROUND Previous studies showed that miR-195a-5p was among the most abundant microRNAs (miRNAs) expressed in the kidney. METHODS Lentivirus silencing of tumor necrosis factor-α (TNF) was performed in vivo and in vitro. Luciferase reporter assays confirmed that bumetanide-sensitive Na+-K+-2Cl- cotransporter isoform A (NKCC2A) mRNA is targeted and repressed by miR-195a-5p. Radiotelemetry was used to measure mean arterial pressure. RESULTS TNF upregulates mmu-miR-195a-5p, and -203 and downregulates mmu-miR-30c and -100 in the medullary thick ascending limb of male mice. miR-195a-5p was >3-fold higher in the renal outer medulla of mice given an intrarenal injection of murine recombinant TNF, whereas silencing TNF inhibited miR-195a-5p expression by ≈51%. Transient transfection of a miR-195a-5p mimic into medullary thick ascending limb cells suppressed NKCC2A mRNA by ≈83%, whereas transfection with Anti-miR-195a-5p increased NKCC2A mRNA. Silencing TNF in medullary thick ascending limb cells prevented increases in miR-195 induced by 400 mosmol/kg H2O medium, an effect reversed by transfection with a miR-195a-5p mimic. Expression of phosphorylated NKCC2 increased 1.5-fold in medullary thick ascending limb cells transfected with Anti-miR-195a-5p and a miR-195a-5p mimic prevented the increase, which was induced by silencing TNF in cells exposed to 400 mosmol/kg H2O medium after osmolality was increased by adding NaCl. Intrarenal injection of TNF suppressed NKCC2A mRNA, whereas injection of miR-195a-5p prevented the increase of NKCC2A mRNA abundance and phosphorylated NKCC2 expression when TNF was silenced. Intrarenal injection with miR-195a-5p markedly attenuated MAP after renal silencing of TNF in mice given 1% NaCl. CONCLUSIONS The study identifies miR-195a-5p as a salt-sensitive and TNF-inducible miRNA that attenuates NaCl-mediated increases in blood pressure by inhibiting NKCC2A.
Collapse
Affiliation(s)
- Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla
| | - Hong Zhao
- Department of Pharmacology, New York Medical College, Valhalla
| | - David H Hao
- Department of Pharmacology, New York Medical College, Valhalla
| | | |
Collapse
|
6
|
Crorkin P, Hao S, Ferreri NR. Responses to Ang II (Angiotensin II), Salt Intake, and Lipopolysaccharide Reveal the Diverse Actions of TNF-α (Tumor Necrosis Factor-α) on Blood Pressure and Renal Function. Hypertension 2022; 79:2656-2670. [PMID: 36129177 PMCID: PMC9649876 DOI: 10.1161/hypertensionaha.122.19464] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
TNF-α (tumor necrosis factor-alpha) is the best known as a proinflammatory cytokine; yet, this cytokine also has important immunomodulatory and regulatory functions. As the effects of TNF-α on immune system function were being revealed, the spectrum of its activities appeared in conflict with each other before investigators defined the settings and mechanisms by which TNF-α contributed to both host defense and chronic inflammation. These effects reflect self-protective mechanisms that may become harmful when dysregulated. The paradigm of physiological and pathophysiological effects of TNF-α has since been uncovered in the lung, colon, and kidney where its role has been identified in pulmonary edema, electrolyte reabsorption, and blood pressure regulation, respectively. Recent studies on the prohypertensive and inflammatory effects of TNF-α in the cardiovascular system juxtaposed to those related to NaCl and blood pressure homeostasis, the response of the kidney to lipopolysaccharide, and protection against bacterial infections are helping define the mechanisms by which TNF-α modulates distinct functions within the kidney. This review discusses how production of TNF-α by renal epithelial cells may contribute to regulatory mechanisms that not only govern electrolyte excretion and blood pressure homeostasis but also maintain the appropriate local hypersalinity environment needed for optimizing the innate immune response to bacterial infections in the kidney. It is possible that the wide range of effects mediated by TNF-α may be related to severity of disease, amount of inflammation and TNF-α levels, and the specific cell types that produce this cytokine, areas that remain to be investigated further.
Collapse
Affiliation(s)
- Patrick Crorkin
- Department of Pharmacology, New York Medical College, Valhalla, NY
| | - Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla, NY
| | | |
Collapse
|
7
|
Mary S, Boder P, Padmanabhan S, McBride MW, Graham D, Delles C, Dominiczak AF. Role of Uromodulin in Salt-Sensitive Hypertension. Hypertension 2022; 79:2419-2429. [PMID: 36378920 PMCID: PMC9553220 DOI: 10.1161/hypertensionaha.122.19888] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The exclusive expression of uromodulin in the kidneys has made it an intriguing protein in kidney and cardiovascular research. Genome-wide association studies discovered variants of uromodulin that are associated with chronic kidney diseases and hypertension. Urinary and circulating uromodulin levels reflect kidney and cardiovascular health as well as overall mortality. More recently, Mendelian randomization studies have shown that genetically driven levels of uromodulin have a causal and adverse effect on kidney function. On a mechanistic level, salt sensitivity is an important factor in the pathophysiology of hypertension, and uromodulin is involved in salt reabsorption via the NKCC2 (Na+-K+-2Cl- cotransporter) on epithelial cells of the ascending limb of loop of Henle. In this review, we provide an overview of the multifaceted physiology and pathophysiology of uromodulin including recent advances in its genetics; cellular trafficking; and mechanistic and clinical studies undertaken to understand the complex relationship between uromodulin, blood pressure, and kidney function. We focus on tubular sodium reabsorption as one of the best understood and pathophysiologically and clinically most important roles of uromodulin, which can lead to therapeutic interventions.
Collapse
Affiliation(s)
- Sheon Mary
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| | - Philipp Boder
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| | - Sandosh Padmanabhan
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| | - Martin W. McBride
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| | - Delyth Graham
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| | - Christian Delles
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| | - Anna F. Dominiczak
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
8
|
The Post-Translational Modification Networking in WNK-Centric Hypertension Regulation and Electrolyte Homeostasis. Biomedicines 2022; 10:biomedicines10092169. [PMID: 36140271 PMCID: PMC9496095 DOI: 10.3390/biomedicines10092169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/26/2022] [Accepted: 08/27/2022] [Indexed: 11/17/2022] Open
Abstract
The with-no-lysine (WNK) kinase family, comprising four serine-threonine protein kinases (WNK1-4), were first linked to hypertension due to their mutations in association with pseudohypoaldosteronism type II (PHAII). WNK kinases regulate crucial blood pressure regulators, SPAK/OSR1, to mediate the post-translational modifications (PTMs) of their downstream ion channel substrates, such as sodium chloride co-transporter (NCC), epithelial sodium chloride (ENaC), renal outer medullary potassium channel (ROMK), and Na/K/2Cl co-transporters (NKCCs). In this review, we summarize the molecular pathways dysregulating the WNKs and their downstream target renal ion transporters. We summarize each of the genetic variants of WNK kinases and the small molecule inhibitors that have been discovered to regulate blood pressure via WNK-triggered PTM cascades.
Collapse
|
9
|
Lu X, Crowley SD. The Immune System in Hypertension: a Lost Shaker of Salt 2021 Lewis K. Dahl Memorial Lecture. Hypertension 2022; 79:1339-1347. [PMID: 35545942 DOI: 10.1161/hypertensionaha.122.18554] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The seminal observations of Dr Lewis Dahl regarding renal mechanisms of hypertension remain highly relevant in light of more recent experiments showing that immune system dysfunction contributes to hypertension pathogenesis. Dr Dahl established that inappropriate salt retention in the kidney plays a central role via Ohm's Law in permitting blood pressure elevation. Nevertheless, inflammatory cytokines whose expression is induced in the early stages of hypertension can alter renal blood flow and sodium transporter expression and activity to foster renal sodium retention. By elaborating these cytokines and reactive oxygen species, myeloid cells and T lymphocytes can connect systemic inflammatory signals to aberrant kidney functions that allow sustained hypertension. By activating T lymphocytes, antigen-presenting cells such as dendritic cells represent an afferent sensing mechanism triggering T cell activation, cytokine generation, and renal salt and water reabsorption. Manipulating these inflammatory signals to attenuate hypertension without causing prohibitive systemic immunosuppression will pose a challenge, but disrupting actions of inflammatory mediators locally within the kidney may offer a path through which to target immune-mediated mechanisms of hypertension while capitalizing on Dr Dahl's key recognition of the kidney's importance in blood pressure regulation.
Collapse
Affiliation(s)
- Xiaohan Lu
- Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC
| | - Steven D Crowley
- Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC
| |
Collapse
|
10
|
Majid DSA, Castillo A. Angiotensin II-induced natriuresis is attenuated in knockout mice lacking the receptors for tumor necrosis factor-α. Physiol Rep 2021; 9:e14942. [PMID: 34337896 PMCID: PMC8326895 DOI: 10.14814/phy2.14942] [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: 02/06/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 11/25/2022] Open
Abstract
Intravenous infusion of relatively higher doses of angiotensin II (AngII) elicits natriuresis as opposed to its usual anti-natruretic response. As AngII can induce tumor necrosis factor-α (TNFα) production which elicits natriuresis via its action on TNFα receptor type 1 (TNFR1), we hypothesize that the concomitant release of TNFα contributes to the natriuretic response to AngII. Responses to AngII infusion (1 ng min-1 g-1 for 75 min, iv) were evaluated in anesthetized knockout (KO) mice lacking TNFR1 (n = 6) and TNFR2 (TNFα receptor type 2; n = 6) and compared these responses with those in wild type (WT; n = 6) mice. Arterial pressure (AP) was recorded from a cannula placed in the carotid artery. Renal blood flow (RBF) and glomerular filtration rate (GFR) were measured by PAH and inulin clearances, respectively. Urine was collected from a catheter placed in the bladder. AngII caused similar increases (p < 0.05 vs basal values) in AP (WT, 37 ± 5%; TNFR1KO, 35 ± 4%; TNFR2KO, 30 ± 4%) and decreases (p < 0.05) in RBF (WT, -39 ± 5%; TNFR1KO, -28 ± 6%; TNFR2KO, -31 ± 4%) without significant changes in GFR (WT, -17 ± 7%; TNFR1KO, -18 ± 7%; TNFR2KO, -12 ± 7%). However, despite similar changes in AP and renal hemodynamics, AngII induced increases (p < 0.05) in urinary sodium excretion in WT (3916 ± 942%) were less in the KO strains, more or less in TNFR1KO (473 ± 170%) than in TNFR2KO (1176 ± 168%). These data indicate that TNF-α receptors, particularly TNFR1 are involved in the natriuretic response that occur during acute infusion of AngII and thus, plays a protective role in preventing excessive salt retention at clinical conditions associated with elevated AngII level.
Collapse
Affiliation(s)
- Dewan S. A. Majid
- Department of PhysiologyTulane Hypertension & Renal Center of ExcellenceTulane University Health Sciences CenterNew OrleansLAUSA
| | - Alexander Castillo
- Department of PhysiologyTulane Hypertension & Renal Center of ExcellenceTulane University Health Sciences CenterNew OrleansLAUSA
| |
Collapse
|
11
|
Majid DSA, Mahaffey E, Castillo A, Prieto MC, Navar LG. Angiotensin II-induced renal angiotensinogen formation is enhanced in mice lacking tumor necrosis factor-alpha type 1 receptor. Physiol Rep 2021; 9:e14990. [PMID: 34427402 PMCID: PMC8383705 DOI: 10.14814/phy2.14990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/30/2021] [Accepted: 07/11/2021] [Indexed: 01/11/2023] Open
Abstract
In hypertension induced by angiotensin II (AngII) administration with high salt (HS) intake, intrarenal angiotensinogen (AGT) and tumor necrosis factor-alpha (TNF-α) levels increase. However, TNF-α has been shown to suppress AGT formation in cultured renal proximal tubular cells. We examined the hypothesis that elevated AngII levels during HS intake reduces TNF-α receptor type 1 (TNFR1) activity in the kidneys, thus facilitating increased intrarenal AGT formation. The responses to HS diet (4% NaCl) with chronic infusion of AngII (25 ng/min) via implanted minipump for 4 weeks were assessed in wild-type (WT) and knockout (KO) mice lacking TNFR1 or TNFR2 receptors. Blood pressure was measured by tail-cuff plethysmography, and 24-h urine samples were collected using metabolic cages prior to start (0 day) and at the end of 2nd and 4th week periods. The urinary excretion rate of AGT (uAGT; marker for intrarenal AGT) was measured using ELISA. HS +AngII treatment for 4 weeks increased mean arterial pressure (MAP) in all strains of mice. However, the increase in MAP in TNFR1KO (77 ± 2 to 115 ± 3 mmHg; n = 7) was significantly greater (p < 0.01) than in WT (76 ± 1 to 102 ± 2 mmHg; n = 7) or in TNFR2KO (78 ± 2 to 99 ± 5 mmHg; n = 6). The increase in uAGT at 4th week was also greater (p < 0.05) in TNFR1KO mice (6 ± 2 to 167 ± 75 ng/24 h) than that in WT (6 ± 3 to 46 ± 16 ng/24 h) or in TNFR2KO mice (8 ± 7 to 65 ± 44 ng/24 h). The results indicate that TNFR1 exerts a protective role by mitigating intrarenal AGT formation induced by elevated AngII and HS intake.
Collapse
MESH Headings
- Angiotensin II/toxicity
- Angiotensinogen/metabolism
- Animals
- Blood Pressure
- Hypertension, Renal/etiology
- Hypertension, Renal/metabolism
- Kidney/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Receptors, Tumor Necrosis Factor, Type I/deficiency
- Receptors, Tumor Necrosis Factor, Type I/genetics
- Receptors, Tumor Necrosis Factor, Type I/metabolism
- Receptors, Tumor Necrosis Factor, Type II/genetics
- Receptors, Tumor Necrosis Factor, Type II/metabolism
- Sodium Chloride, Dietary/toxicity
Collapse
Affiliation(s)
- Dewan S. A. Majid
- Department of PhysiologyHypertension & Renal Center of ExcellenceTulane University School of MedicineNew OrleansLouisianaUSA
| | - Eamonn Mahaffey
- Department of PhysiologyHypertension & Renal Center of ExcellenceTulane University School of MedicineNew OrleansLouisianaUSA
| | - Alexander Castillo
- Department of PhysiologyHypertension & Renal Center of ExcellenceTulane University School of MedicineNew OrleansLouisianaUSA
| | - Minolfa C. Prieto
- Department of PhysiologyHypertension & Renal Center of ExcellenceTulane University School of MedicineNew OrleansLouisianaUSA
| | - L. Gabriel Navar
- Department of PhysiologyHypertension & Renal Center of ExcellenceTulane University School of MedicineNew OrleansLouisianaUSA
| |
Collapse
|
12
|
Boder P, Mary S, Mark PB, Leiper J, Dominiczak AF, Padmanabhan S, Rampoldi L, Delles C. Mechanistic interactions of uromodulin with the thick ascending limb: perspectives in physiology and hypertension. J Hypertens 2021; 39:1490-1504. [PMID: 34187999 PMCID: PMC7611110 DOI: 10.1097/hjh.0000000000002861] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hypertension is a significant risk factor for cardiovascular disease and mortality worldwide. The kidney is a major regulator of blood pressure and electrolyte homeostasis, with monogenic disorders indicating a link between abnormal ion transport and salt-sensitive hypertension. However, the association between salt and hypertension remains controversial. Thus, there is continued interest in deciphering the molecular mechanisms behind these processes. Uromodulin (UMOD) is the most abundant protein in the normal urine and is primarily synthesized by the thick ascending limb epithelial cells of the kidney. Genome-wide association studies have linked common UMOD variants with kidney function, susceptibility to chronic kidney disease and hypertension independent of renal excretory function. This review will discuss and provide predictions on the role of the UMOD protein in renal ion transport and hypertension based on current observational, biochemical, genetic, pharmacological and clinical evidence.
Collapse
Affiliation(s)
- Philipp Boder
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Sheon Mary
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Patrick B. Mark
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - James Leiper
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Anna F. Dominiczak
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Sandosh Padmanabhan
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Luca Rampoldi
- Molecular Genetics of Renal Disorders Unit, Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Christian Delles
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
13
|
Gatzoflias S, Hao S, Ferreri NR. Induction of renal tumor necrosis factor-α and other autacoids and the beneficial effects of hypertonic saline in acute decompensated heart failure. Am J Physiol Renal Physiol 2021; 320:F1159-F1164. [PMID: 33969695 DOI: 10.1152/ajprenal.00686.2020] [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: 01/12/2023] Open
Abstract
Although administration of hypertonic saline (HSS) in combination with diuretics has yielded improved weight loss, preservation of renal function, and reduction in hospitalization time in the clinical setting of patients with acute decompensated heart failure (ADHF), the mechanisms that underlie these beneficial effects remain unclear and additional studies are needed before this approach can be adopted on a more consistent basis. As high salt conditions stimulate the production of several renal autacoids that exhibit natriuretic effects, renal physiologists can contribute to the understanding of mechanisms by which HSS leads to increased diuresis both as an individual therapy as well as in combination with loop diuretics. For instance, since HSS increases TNF-α production by proximal tubule and thick ascending limb of Henle's loop epithelial cells, this article is aimed at highlighting how the effects of TNF-α produced by these cell types may contribute to the beneficial effects of HSS in patients with ADHF. Although TNF-α produced by infiltrating macrophages and T cells exacerbates and attenuates renal damage, respectively, production of this cytokine within the tubular compartment of the kidney functions as an intrinsic regulator of blood pressure and Na+ homeostasis via mechanisms along the nephron related to inhibition of Na+-K+-2Cl- cotransporter isoform 2 activity and angiotensinogen expression. Thus, in the clinical setting of ADHF and hyponatremia, induction of TNF-α production along the nephron by administration of HSS may attenuate Na+-K+-2Cl- cotransporter isoform 2 activity and angiotensinogen expression as part of a mechanism that prevents excessive Na+ reabsorption in the thick ascending limb of Henle's loop, thereby mitigating volume overload.
Collapse
Affiliation(s)
| | - Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, New York
| |
Collapse
|
14
|
Hao S, Salzo J, Hao M, Ferreri NR. Regulation of NKCC2B by TNF-α in response to salt restriction. Am J Physiol Renal Physiol 2019; 318:F273-F282. [PMID: 31813248 DOI: 10.1152/ajprenal.00388.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have previously shown that TNF-α produced by renal epithelial cells inhibits Na+-K+-2Cl- cotransporter (NKCC2) activity as part of a mechanism that attenuates increases in blood pressure in response to high NaCl intake. As the role of TNF-α in the kidney is still being defined, the effects of low salt intake on TNF-α and NKCC2B expression were determined. Mice given a low-salt (0.02% NaCl) diet (LSD) for 7 days exhibited a 62 ± 7.4% decrease in TNF-α mRNA accumulation in the renal cortex. Mice that ingested the LSD also exhibited an ~63% increase in phosphorylated NKCC2 expression in the cortical thick ascending limb of Henle's loop and a concomitant threefold increase in NKCC2B mRNA abundance without a concurrent change in NKCC2A mRNA accumulation. NKCC2B mRNA levels increased fivefold in mice that ingested the LSD and also received an intrarenal injection of a lentivirus construct that specifically silenced TNF-α in the kidney (U6-TNF-ex4) compared with mice injected with control lentivirus. Administration of a single intrarenal injection of murine recombinant TNF-α (5 ng/g body wt) attenuated the increases of NKCC2B mRNA by ~50% and inhibited the increase in phosphorylated NKCC2 by ~54% in the renal cortex of mice given the LSD for 7 days. Renal silencing of TNF-α decreased urine volume and NaCl excretion in mice given the LSD, effects that were reversed when NKCC2B was silenced in the kidney. Collectively, these findings demonstrate that downregulation of renal TNF-α production in response to low-salt conditions contributes to the regulation of NaCl reabsorption via an NKCC2B-dependent mechanism.
Collapse
Affiliation(s)
- Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Joseph Salzo
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Mary Hao
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, New York
| |
Collapse
|
15
|
Gonzalez-Vicente A, Saez F, Monzon CM, Asirwatham J, Garvin JL. Thick Ascending Limb Sodium Transport in the Pathogenesis of Hypertension. Physiol Rev 2019; 99:235-309. [PMID: 30354966 DOI: 10.1152/physrev.00055.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The thick ascending limb plays a key role in maintaining water and electrolyte balance. The importance of this segment in regulating blood pressure is evidenced by the effect of loop diuretics or local genetic defects on this parameter. Hormones and factors produced by thick ascending limbs have both autocrine and paracrine effects, which can extend prohypertensive signaling to other structures of the nephron. In this review, we discuss the role of the thick ascending limb in the development of hypertension, not as a sole participant, but one that works within the rich biological context of the renal medulla. We first provide an overview of the basic physiology of the segment and the anatomical considerations necessary to understand its relationship with other renal structures. We explore the physiopathological changes in thick ascending limbs occurring in both genetic and induced animal models of hypertension. We then discuss the racial differences and genetic defects that affect blood pressure in humans through changes in thick ascending limb transport rates. Throughout the text, we scrutinize methodologies and discuss the limitations of research techniques that, when overlooked, can lead investigators to make erroneous conclusions. Thus, in addition to advancing an understanding of the basic mechanisms of physiology, the ultimate goal of this work is to understand our research tools, to make better use of them, and to contextualize research data. Future advances in renal hypertension research will require not only collection of new experimental data, but also integration of our current knowledge.
Collapse
Affiliation(s)
| | - Fara Saez
- Department of Physiology and Biophysics, Case Western Reserve University , Cleveland, Ohio
| | - Casandra M Monzon
- Department of Physiology and Biophysics, Case Western Reserve University , Cleveland, Ohio
| | - Jessica Asirwatham
- Department of Physiology and Biophysics, Case Western Reserve University , Cleveland, Ohio
| | - Jeffrey L Garvin
- Department of Physiology and Biophysics, Case Western Reserve University , Cleveland, Ohio
| |
Collapse
|
16
|
Zhang G, Gui S, Wang W, Meng D, Meng Q, Luan H, Zhao R, Zhang J, Sui H. Acute stimulatory effect of tumor necrosis factor on the basolateral 50 pS K channels in the thick ascending limb of the rat kidney. Mol Med Rep 2018; 18:4733-4738. [PMID: 30221721 DOI: 10.3892/mmr.2018.9475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 08/13/2018] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to investigate the acute effect and mechanism of tumor necrosis factor (TNF) on basolateral 50 pS K channels in the thick ascending limb (TAL) of the rat kidney. The TAL tubules were isolated from the rat kidney, and the activity of the 50 pS K channels was recorded using the patch‑clamp technique. The results indicated that the application of TNF (10 nM) significantly activated the 50 pS K channels and the TNF effect was concentration‑dependent. Inhibition of protein kinase A, phospholipase A2 and protein tyrosine kinase using pathway inhibitors (H89, AACOCF3 and Herbimycin A, respectively) did not abolish the stimulatory effect of TNF, indicating that none of these pathways mediated the TNF effect. By contrast, the phenylarsine oxide inhibitor against protein tyrosine phosphatase (PTP) decreased the activity of the 50 pS K channels and blocked the stimulatory effect of TNF on these channels. Furthermore, western blot analysis demonstrated that the application of TNF (10 nM) in the TAL increased the phosphorylation of PTP, an indication of PTP activity stimulation. Thus, it was concluded that the acute application of TNF may stimulate the basolateral 50 pS K channel in the TAL and the stimulatory effect of TNF may be mediated by the PTP‑dependent pathway.
Collapse
Affiliation(s)
- Guoyan Zhang
- Department of Urology, First Affiliated Hospital, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Shiliang Gui
- Department of Urology, First Affiliated Hospital, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Weiqun Wang
- Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Dexin Meng
- Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Qingmin Meng
- Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Haiyan Luan
- Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Rixin Zhao
- Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Jiatian Zhang
- Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| | - Hongyu Sui
- Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China
| |
Collapse
|
17
|
Hao S, Hao M, Ferreri NR. Renal-Specific Silencing of TNF (Tumor Necrosis Factor) Unmasks Salt-Dependent Increases in Blood Pressure via an NKCC2A (Na +-K +-2Cl - Cotransporter Isoform A)-Dependent Mechanism. Hypertension 2018; 71:1117-1125. [PMID: 29735631 DOI: 10.1161/hypertensionaha.117.10764] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/02/2018] [Accepted: 03/23/2018] [Indexed: 01/11/2023]
Abstract
We tested the hypothesis that TNF (tumor necrosis factor)-α produced within the kidney and acting on the renal tubular system is part of a regulatory mechanism that attenuates increases in blood pressure in response to high salt intake. Intrarenal administration of a lentivirus construct, which specifically silenced TNF in the kidney, did not affect baseline blood pressure. However, blood pressure increased significantly 1 day after mice with intrarenal silencing of TNF ingested 1% NaCl in the drinking water. The increase in blood pressure, which was continuously observed for 11 days, promptly returned to baseline levels when mice were switched from 1% NaCl to tap water. Silencing of renal TNF also increased NKCC2 (Na+-K+-2Cl- cotransporter) phosphorylation and induced a selective increase in NKCC2A (NKCC2 isoform A) mRNA accumulation in both the cortical and medullary thick ascending limb of Henle loop that was neither associated with a compensatory decrease of NKCC2F in the medulla nor NKCC2B in the cortex. The NaCl-mediated increases in blood pressure were completely absent when NKCC2A, using a lentivirus construct that did not alter expression of NKCC2F or NKCC2B, and TNF were concomitantly silenced in the kidney. Moreover, the decrease in urine volume and NaCl excretion induced by renal TNF silencing was abolished when NKCC2A was concurrently silenced, suggesting that this isoform contributes to the transition from a salt-resistant to salt-sensitive phenotype. Collectively, the data are the first to demonstrate a role for TNF produced by the kidney in the modulation of sodium homeostasis and blood pressure regulation.
Collapse
MESH Headings
- Animals
- Blood Pressure/physiology
- Blotting, Western
- Disease Models, Animal
- Enzyme-Linked Immunosorbent Assay
- Gene Expression Regulation
- Hypertension, Renal/genetics
- Hypertension, Renal/metabolism
- Hypertension, Renal/physiopathology
- Kidney/metabolism
- Kidney/pathology
- Male
- Mice
- Mice, Inbred C57BL
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sodium Chloride/toxicity
- Solute Carrier Family 12, Member 1/biosynthesis
- Solute Carrier Family 12, Member 1/genetics
- Transcription, Genetic
- Tumor Necrosis Factor-alpha/metabolism
Collapse
Affiliation(s)
- Shoujin Hao
- From the Department of Pharmacology, New York Medical College, Valhalla
| | - Mary Hao
- From the Department of Pharmacology, New York Medical College, Valhalla
| | - Nicholas R Ferreri
- From the Department of Pharmacology, New York Medical College, Valhalla.
| |
Collapse
|
18
|
Graham LA, Dominiczak AF, Ferreri NR. Role of renal transporters and novel regulatory interactions in the TAL that control blood pressure. Physiol Genomics 2017; 49:261-276. [PMID: 28389525 PMCID: PMC5451551 DOI: 10.1152/physiolgenomics.00017.2017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 03/27/2017] [Accepted: 04/05/2017] [Indexed: 12/31/2022] Open
Abstract
Hypertension (HTN), a major public health issue is currently the leading factor in the global burden of disease, where associated complications account for 9.4 million deaths worldwide every year. Excessive dietary salt intake is among the environmental factors that contribute to HTN, known as salt sensitivity. The heterogeneity of salt sensitivity and the multiple mechanisms that link high salt intake to increases in blood pressure are of upmost importance for therapeutic application. A continual increase in the kidney's reabsorption of sodium (Na+) relies on sequential actions at various segments along the nephron. When the distal segments of the nephron fail to regulate Na+, the effects on Na+ homeostasis are unfavorable. We propose that the specific nephron region where increased active uptake occurs as a result of variations in Na+ reabsorption is at the thick ascending limb of the loop of Henle (TAL). The purpose of this review is to urge the consideration of the TAL as contributing to the pathophysiology of salt-sensitive HTN. Further research in this area will enable development of a therapeutic application for targeted treatment.
Collapse
Affiliation(s)
- Lesley A Graham
- BHF Glasgow Cardiovascular Research Centre, University of Glasgow Cardiovascular and Medical Sciences, Glasgow, United Kingdom; and
| | - Anna F Dominiczak
- BHF Glasgow Cardiovascular Research Centre, University of Glasgow Cardiovascular and Medical Sciences, Glasgow, United Kingdom; and
| | - Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, New York
| |
Collapse
|
19
|
Norlander AE, Madhur MS. Inflammatory cytokines regulate renal sodium transporters: how, where, and why? Am J Physiol Renal Physiol 2017; 313:F141-F144. [PMID: 28404590 DOI: 10.1152/ajprenal.00465.2016] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 03/29/2017] [Accepted: 04/10/2017] [Indexed: 12/13/2022] Open
Abstract
Hypertension is growing in epidemic proportions worldwide and is now the leading preventable cause of premature death. For over a century, we have known that the kidney plays a critical role in blood pressure regulation. Specifically, abnormalities in renal sodium transport appear to be a final common pathway that gives rise to elevated blood pressure regardless of the nature of the initial hypertensive stimulus. However, it is only in the past decade that we have come to realize that inflammatory cytokines secreted by innate and adaptive immune cells, as well as renal epithelial cells, can modulate the expression and activity of sodium transporters all along the nephron, leading to alterations in pressure natriuresis, sodium and water balance, and ultimately hypertension. This mini-review highlights specific cytokines and the transporters that they regulate and discusses why inflammatory cytokines may have evolved to serve this function.
Collapse
Affiliation(s)
- Allison E Norlander
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville Tennesee; and
| | - Meena S Madhur
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville Tennesee; and .,Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| |
Collapse
|
20
|
Huang B, Cheng Y, Usa K, Liu Y, Baker MA, Mattson DL, He Y, Wang N, Liang M. Renal Tumor Necrosis Factor α Contributes to Hypertension in Dahl Salt-Sensitive Rats. Sci Rep 2016; 6:21960. [PMID: 26916681 PMCID: PMC4768148 DOI: 10.1038/srep21960] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 02/03/2016] [Indexed: 02/08/2023] Open
Abstract
Tumor necrosis factor α (TNFα) is a major proinflammatory cytokine and its level is elevated in hypertensive states. Inflammation occurs in the kidneys during the development of hypertension. We hypothesized that TNFα specifically in the kidney contributes to the development of hypertension and renal injury in Dahl salt-sensitive (SS) rats, a widely used model of human salt-sensitive hypertension and renal injury. SS rats were chronically instrumented for renal interstitial infusion and blood pressure measurement in conscious, freely moving state. Gene expression was measured using real-time PCR and renal injury assessed with histological analysis. The abundance of TNFα in the renal medulla of SS rats, but not the salt-insensitive congenic SS.13BN26 rats, was significantly increased when rats had been fed a high-salt diet for 7 days (n = 6 or 9, p < 0.01). The abundance of TNFα receptors in the renal medulla was significantly higher in SS rats than SS.13BN26 rats. Renal interstitial administration of Etanercept, an inhibitor of TNFα, significantly attenuated the development of hypertension in SS rats on a high-salt diet (n = 7–8, p < 0.05). Glomerulosclerosis and interstitial fibrosis were also significantly ameliorated. These findings indicate intrarenal TNFα contributes to the development of hypertension and renal injury in SS rats.
Collapse
Affiliation(s)
- Baorui Huang
- Department of Nephrology and Rheumatology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, P.R.China.,Medical College of Soochow University, Suzhou, Jiangsu, P.R.China.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Yuan Cheng
- Center of Systems Molecular Medicine, Milwaukee, WI, USA.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Department of Nephrology, Shenzhen Second People's Hospital and the First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Kristie Usa
- Center of Systems Molecular Medicine, Milwaukee, WI, USA.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Yong Liu
- Center of Systems Molecular Medicine, Milwaukee, WI, USA.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Maria Angeles Baker
- Center of Systems Molecular Medicine, Milwaukee, WI, USA.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - David L Mattson
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Yongcheng He
- Department of Nephrology, Shenzhen Second People's Hospital and the First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Niansong Wang
- Department of Nephrology and Rheumatology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, P.R.China
| | - Mingyu Liang
- Center of Systems Molecular Medicine, Milwaukee, WI, USA.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
| |
Collapse
|
21
|
Proinflammatory Cytokines and Potassium Channels in the Kidney. Mediators Inflamm 2015; 2015:362768. [PMID: 26508816 PMCID: PMC4609835 DOI: 10.1155/2015/362768] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/09/2015] [Indexed: 01/08/2023] Open
Abstract
Proinflammatory cytokines affect several cell functions via receptor-mediated processes. In the kidney, functions of transporters and ion channels along the nephron are also affected by some cytokines. Among these, alteration of activity of potassium ion (K(+)) channels induces changes in transepithelial transport of solutes and water in the kidney, since K(+) channels in tubule cells are indispensable for formation of membrane potential which serves as a driving force for the transepithelial transport. Altered K(+) channel activity may be involved in renal cell dysfunction during inflammation. Although little information was available regarding the effects of proinflammatory cytokines on renal K(+) channels, reports have emerged during the last decade. In human proximal tubule cells, interferon-γ showed a time-dependent biphasic effect on a 40 pS K(+) channel, that is, delayed suppression and acute stimulation, and interleukin-1β acutely suppressed the channel activity. Transforming growth factor-β1 activated KCa3.1 K(+) channel in immortalized human proximal tubule cells, which would be involved in the pathogenesis of renal fibrosis. This review discusses the effects of proinflammatory cytokines on renal K(+) channels and the causal relationship between the cytokine-induced changes in K(+) channel activity and renal dysfunction.
Collapse
|
22
|
Borschewski A, Himmerkus N, Boldt C, Blankenstein KI, McCormick JA, Lazelle R, Willnow TE, Jankowski V, Plain A, Bleich M, Ellison DH, Bachmann S, Mutig K. Calcineurin and Sorting-Related Receptor with A-Type Repeats Interact to Regulate the Renal Na⁺-K⁺-2Cl⁻ Cotransporter. J Am Soc Nephrol 2015; 27:107-19. [PMID: 25967121 DOI: 10.1681/asn.2014070728] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 03/16/2015] [Indexed: 01/08/2023] Open
Abstract
The furosemide-sensitive Na(+)-K(+)-2Cl(-)-cotransporter (NKCC2) is crucial for NaCl reabsorption in kidney thick ascending limb (TAL) and drives the urine concentrating mechanism. NKCC2 activity is modulated by N-terminal phosphorylation and dephosphorylation. Serine-threonine kinases that activate NKCC2 have been identified, but less is known about phosphatases that deactivate NKCC2. Inhibition of calcineurin phosphatase has been shown to stimulate transport in the TAL and the distal convoluted tubule. Here, we identified NKCC2 as a target of the calcineurin Aβ isoform. Short-term cyclosporine administration in mice augmented the abundance of phospho-NKCC2, and treatment of isolated TAL with cyclosporine increased the chloride affinity and transport activity of NKCC2. Because sorting-related receptor with A-type repeats (SORLA) may affect NKCC2 phosphoregulation, we used SORLA-knockout mice to test whether SORLA is involved in calcineurin-dependent modulation of NKCC2. SORLA-deficient mice showed more calcineurin Aβ in the apical region of TAL cells and less NKCC2 phosphorylation and activity compared with littermate controls. In contrast, overexpression of SORLA in cultured cells reduced the abundance of endogenous calcineurin Aβ. Cyclosporine administration rapidly normalized the abundance of phospho-NKCC2 in SORLA-deficient mice, and a functional interaction between calcineurin Aβ and SORLA was further corroborated by binding assays in rat kidney extracts. In summary, we have shown that calcineurin Aβ and SORLA are key components in the phosphoregulation of NKCC2. These results may have clinical implications for immunosuppressive therapy using calcineurin inhibitors.
Collapse
Affiliation(s)
- Aljona Borschewski
- Department of Anatomy, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Christin Boldt
- Department of Anatomy, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - James A McCormick
- Division of Nephrology and Hypertension, Oregon Health & Science University and VA Medical Center, Portland, Oregon
| | - Rebecca Lazelle
- Division of Nephrology and Hypertension, Oregon Health & Science University and VA Medical Center, Portland, Oregon
| | - Thomas E Willnow
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany; and
| | - Vera Jankowski
- Medizinische Klinik IV, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Allein Plain
- Institute of Physiology, Kiel University, Kiel, Germany
| | - Markus Bleich
- Institute of Physiology, Kiel University, Kiel, Germany
| | - David H Ellison
- Division of Nephrology and Hypertension, Oregon Health & Science University and VA Medical Center, Portland, Oregon
| | - Sebastian Bachmann
- Department of Anatomy, Charité-Universitätsmedizin Berlin, Berlin, Germany;
| | - Kerim Mutig
- Department of Anatomy, Charité-Universitätsmedizin Berlin, Berlin, Germany;
| |
Collapse
|
23
|
Heitmeier M, McCracken R, Micanovic R, Khan S, El-Achkar TM. The role of tumor necrosis factor alpha in regulating the expression of Tamm-Horsfall Protein (uromodulin) in thick ascending limbs during kidney injury. Am J Nephrol 2014; 40:458-67. [PMID: 25503683 DOI: 10.1159/000369836] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 11/10/2014] [Indexed: 12/26/2022]
Abstract
BACKGROUND Tamm-Horsfall Protein (THP) is a glycoprotein expressed exclusively by cells of the thick ascending loop (TAL) of Henle. THP has a protective role in acute kidney injury (AKI), and its expression is downregulated in the early stages of injury. Tumor necrosis factor alpha (TNFα) is a cytokine endogenously expressed by the TAL and is also induced by AKI. Therefore, we hypothesized that TNFα is a key regulator of THP expression. METHODS We used a mouse model of AKI (ischemia-reperfusion injury, IRI) and a cell culture system of a TAL cell line (MKTAL). RESULTS We show that TNFα is upregulated by TAL cells early after AKI in vivo. The expression of THP and its transcription factor Hepatocyte nuclear factor 1β (HNF1β) were concomitantly decreased at the peak of injury. Furthermore, recombinant TNFα inhibits significantly, and in a dose-dependent manner, the expression of THP, but not HNF1β in MKTAL cells. Interestingly, neither TNFα neutralization nor genetic deletion of TNFα increased THP or HNF levels after injury in vivo. CONCLUSION Our data suggest that TNFα can inhibit the expression of THP in TAL cells via an HNF1β-independent mechanism, but the downregulation of THP expression in the early AKI does not depend on TNFα. We propose that TNFα regulates THP expression in a homeostatic setting, but the impact of TNFα on THP during kidney injury is superseded by other factors that could inhibit HNF1β-mediated expression of THP.
Collapse
|
24
|
Padmanabhan S, Graham L, Ferreri NR, Graham D, McBride M, Dominiczak AF. Uromodulin, an Emerging Novel Pathway for Blood Pressure Regulation and Hypertension. Hypertension 2014; 64:918-23. [DOI: 10.1161/hypertensionaha.114.03132] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Sandosh Padmanabhan
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Lesley Graham
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Nicholas R. Ferreri
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Delyth Graham
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Martin McBride
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Anna F. Dominiczak
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| |
Collapse
|
25
|
Zhang J, Patel MB, Griffiths R, Mao A, Song YS, Karlovich NS, Sparks MA, Jin H, Wu M, Lin EE, Crowley SD. Tumor necrosis factor-α produced in the kidney contributes to angiotensin II-dependent hypertension. Hypertension 2014; 64:1275-81. [PMID: 25185128 DOI: 10.1161/hypertensionaha.114.03863] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Immune system activation contributes to the pathogenesis of hypertension and the resulting progression of chronic kidney disease. In this regard, we recently identified a role for proinflammatory Th1 T-lymphocyte responses in hypertensive kidney injury. Because Th1 cells generate interferon-γ and tumor necrosis factor-α (TNF-α), we hypothesized that interferon-γ and TNF-α propagate renal damage during hypertension induced by activation of the renin-angiotensin system. Therefore, after confirming that mice genetically deficient of Th1 immunity were protected from kidney glomerular injury despite a preserved hypertensive response, we subjected mice lacking interferon-γ or TNF-α to our model of hypertensive chronic kidney disease. Interferon deficiency had no impact on blood pressure elevation or urinary albumin excretion during chronic angiotensin II infusion. By contrast, TNF-deficient (knockout) mice had blunted hypertensive responses and reduced end-organ damage in our model. As angiotensin II-infused TNF knockout mice had exaggerated endothelial nitric oxide synthase expression in the kidney and enhanced nitric oxide bioavailability, we examined the actions of TNF-α generated from renal parenchymal cells in hypertension by transplanting wild-type or TNF knockout kidneys into wild-type recipients before the induction of hypertension. Transplant recipients lacking TNF solely in the kidney had blunted hypertensive responses to angiotensin II and augmented renal endothelial nitric oxide synthase expression, confirming a role for kidney-derived TNF-α to promote angiotensin II-induced blood pressure elevation by limiting renal nitric oxide generation.
Collapse
Affiliation(s)
- Jiandong Zhang
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Mehul B Patel
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Robert Griffiths
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Alice Mao
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Young-soo Song
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Norah S Karlovich
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Matthew A Sparks
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Huixia Jin
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Min Wu
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Eugene E Lin
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.)
| | - Steven D Crowley
- From the Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, NC (J.Z., M.B.P., R.G., A.M., Y.-s.S., N.S.K., M.S., H.J., S.D.C.); Department of Biology, University of Virginia, Charlottesville (E.E.L.); and Department of Medicine, Southeast University, Nanjing, China (M.W.).
| |
Collapse
|
26
|
Mathis KW, Wallace K, Flynn ER, Maric-Bilkan C, LaMarca B, Ryan MJ. Preventing autoimmunity protects against the development of hypertension and renal injury. Hypertension 2014; 64:792-800. [PMID: 25024282 DOI: 10.1161/hypertensionaha.114.04006] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Several studies suggest a link between autoimmunity and essential hypertension in humans. However, whether autoimmunity can drive the development of hypertension remains unclear. The autoimmune disease systemic lupus erythematosus is characterized by autoantibody production, and the prevalence of hypertension is increased markedly in this patient population compared with normal healthy women. We hypothesized that preventing the development of autoimmunity would prevent the development of hypertension in a mouse model of lupus. Female lupus (NZBWF1) and control mice (NZW) were treated weekly with anti-CD20 or immunoglobulin G antibodies (both 10 mg/kg, IV) starting at 20 weeks of age for 14 weeks. Anti-CD20 therapy markedly attenuated lupus disease progression as evidenced by reduced CD45R+ B cells and lower double-stranded DNA autoantibody activity. In addition, renal injury in the form of urinary albumin, glomerulosclerosis, and tubulointerstitial fibrosis, as well as tubular injury (indicated by renal cortical expression of neutrophil gelatinase-associated lipocalin) was prevented by anti-CD20 therapy in lupus mice. Finally, lupus mice treated with anti-CD20 antibody did not develop hypertension. The protection against the development of hypertension was associated with lower renal cortical tumor necrosis factor-α expression, a cytokine that has been previously reported by us to contribute to the hypertension in this model, as well as renal cortical monocyte chemoattractant protein-1 expression and circulating T cells. These data suggest that the development of autoimmunity and the resultant increase in renal inflammation are an important underlying factor in the prevalent hypertension that occurs during systemic lupus erythematosus.
Collapse
Affiliation(s)
- Keisa W Mathis
- From the Departments of Physiology and Biophysics (K.W.M., E.R.F., C.M.-B., M.J.R.), Obstetrics and Gynecology (K.W.), and Pharmacology and Toxicology (B.L.), University of Mississippi Medical Center, Jackson
| | - Kedra Wallace
- From the Departments of Physiology and Biophysics (K.W.M., E.R.F., C.M.-B., M.J.R.), Obstetrics and Gynecology (K.W.), and Pharmacology and Toxicology (B.L.), University of Mississippi Medical Center, Jackson
| | - Elizabeth R Flynn
- From the Departments of Physiology and Biophysics (K.W.M., E.R.F., C.M.-B., M.J.R.), Obstetrics and Gynecology (K.W.), and Pharmacology and Toxicology (B.L.), University of Mississippi Medical Center, Jackson
| | - Christine Maric-Bilkan
- From the Departments of Physiology and Biophysics (K.W.M., E.R.F., C.M.-B., M.J.R.), Obstetrics and Gynecology (K.W.), and Pharmacology and Toxicology (B.L.), University of Mississippi Medical Center, Jackson
| | - Babbette LaMarca
- From the Departments of Physiology and Biophysics (K.W.M., E.R.F., C.M.-B., M.J.R.), Obstetrics and Gynecology (K.W.), and Pharmacology and Toxicology (B.L.), University of Mississippi Medical Center, Jackson
| | - Michael J Ryan
- From the Departments of Physiology and Biophysics (K.W.M., E.R.F., C.M.-B., M.J.R.), Obstetrics and Gynecology (K.W.), and Pharmacology and Toxicology (B.L.), University of Mississippi Medical Center, Jackson.
| |
Collapse
|
27
|
Graham LA, Padmanabhan S, Fraser NJ, Kumar S, Bates JM, Raffi HS, Welsh P, Beattie W, Hao S, Leh S, Hultstrom M, Ferreri NR, Dominiczak AF, Graham D, McBride MW. Validation of Uromodulin as a Candidate Gene for Human Essential Hypertension. Hypertension 2014; 63:551-8. [DOI: 10.1161/hypertensionaha.113.01423] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A recent genome-wide association study identified a locus on chromosome 16 in the promoter region of the uromodulin (
UMOD
) gene that is associated with hypertension. Here, we examined the hypertension signal with functional studies in Umod knockout (KO) mice. Systolic blood pressure was significantly lower in KO versus wild-type (WT) mice under basal conditions (KO: 116.6±0.3 mm Hg versus WT: 136.2±0.4 mm Hg;
P
<0.0001). Administration of 2% NaCl did not alter systolic blood pressure in KO mice, whereas it increased in WT mice by ≈33%,
P
<0.001. The average 24-hour urinary sodium excretion in the KO was greater than that of WT mice (
P
<0.001). Chronic renal function curves demonstrate a leftward shift in KO mice, suggesting that the relationship between UMOD and blood pressure is affected by sodium. Creatinine clearance was increased during salt loading with 2% NaCl in the KO mice, leading to augmented filtered Na
+
excretion and further Na
+
loss. The difference in sodium uptake that exists between WT and KO strains was explored at the molecular level. Urinary tumor necrosis factor-α levels were significantly higher in KO mice compared with WT mice (
P
<0.0001). Stimulation of primary thick ascending limb of the loop of Henle cells with exogenous tumor necrosis factor-α caused a reduction in NKCC2A expression (
P
<0.001) with a concurrent rise in the levels of UMOD mRNA (
P
<0.001). Collectively, we demonstrate that UMOD regulates sodium uptake in the thick ascending limb of the loop of Henle by modulating the effect of tumor necrosis factor-α on NKCC2A expression, making UMOD an important determinant of blood pressure control.
Collapse
Affiliation(s)
- Lesley A. Graham
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Sandosh Padmanabhan
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Niall J. Fraser
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Satish Kumar
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - James M. Bates
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Hajamohideen S. Raffi
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Paul Welsh
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Wendy Beattie
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Shoujin Hao
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Sabine Leh
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Michael Hultstrom
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Nicholas R. Ferreri
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Anna F. Dominiczak
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Delyth Graham
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Martin W. McBride
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| |
Collapse
|
28
|
Crowley SD. The cooperative roles of inflammation and oxidative stress in the pathogenesis of hypertension. Antioxid Redox Signal 2014; 20:102-20. [PMID: 23472597 PMCID: PMC3880899 DOI: 10.1089/ars.2013.5258] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
SIGNIFICANCE Innate and adaptive immunity play fundamental roles in the development of hypertension and its complications. As effectors of the cell-mediated immune response, myeloid cells and T lymphocytes protect the host organism from infection by attacking foreign intruders with bursts of reactive oxygen species (ROS). RECENT ADVANCES While these ROS may help to preserve the vascular tone and thereby protect against circulatory collapse in the face of overwhelming infection, aberrant elaboration of ROS triggered by immune cells in the absence of a hemodynamic insult can lead to pathologic increases in blood pressure. Conversely, misdirected oxidative stress in cardiovascular control organs, including the vasculature, the kidney, and the nervous system potentiates inflammatory responses, augmenting blood pressure elevation and inciting target organ damage. CRITICAL ISSUES Inflammation and oxidative stress thereby act as cooperative and synergistic partners in the pathogenesis of hypertension. FUTURE DIRECTIONS Pharmacologic interventions for hypertensive patients will need to exploit this robust bidirectional relationship between ROS generation and immune activation in cardiovascular control organs to maximize therapeutic benefit, while limiting off-target side effects.
Collapse
Affiliation(s)
- Steven D Crowley
- Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers , Durham, North Carolina
| |
Collapse
|
29
|
Hao S, Bellner L, Zhao H, Ratliff BB, Darzynkiewicz Z, Vio CP, Ferreri NR. NFAT5 is protective against ischemic acute kidney injury. Hypertension 2013; 63:e46-52. [PMID: 24379188 DOI: 10.1161/hypertensionaha.113.02476] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
NFAT5 is a transcription factor that protects the kidney from hypertonic stress and also is activated by hypoxia. We hypothesized that NFAT5 mitigates the extent of renal damage induced by ischemia-reperfusion injury (IRI). Mice were subjected to IRI by unilateral clamping of the left renal pedicle for 30 minutes followed by reperfusion. After 3 hours of reperfusion, the level of NFAT5 mRNA was similar in contralateral and clamped kidneys. However, after 48 hours, NFAT5 mRNA accumulation increased ≈3-fold in both outer medulla and medullary thick ascending limb tubules. NFAT1 levels were elevated at 3 hours but did not increase further at 48 hours. Mice were then either pretreated for 72 hours with an intrarenal injection of a lentivirus short-hairpin RNA construct to silence NFAT5 (enhanced green fluorescent protein-U6-N5-ex8) or a control vector (enhanced green fluorescent protein-U6) before induction of IRI. Neutrophil gelatinase-associated lipocalin and kidney ischemia molecule-1 mRNA levels increased after IRI and further increased after knockdown of NFAT5, suggesting that silencing of NFAT5 exacerbates renal damage during IRI. In contrast, silencing of NFAT1 had no effect on the levels of neutrophil gelatinase-associated lipocalin or kidney ischemia molecule-1 mRNA. Hematoxylin and eosin staining revealed patchy denudation of renal epithelial cells and tubular dilation when NFAT5 was silenced. The number of TUNEL-positive cells in the outer and inner medulla of the clamped kidney increased nearly 2-fold after knockdown of NFAT5 and was associated with an increase in the number of caspase-3-positive cells. Collectively, the data suggest that NFAT5 is part of a protective mechanism that limits renal damage induced by IRI.
Collapse
Affiliation(s)
- Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595.
| | | | | | | | | | | | | |
Collapse
|
30
|
Ramseyer VD, Garvin JL. Tumor necrosis factor-α: regulation of renal function and blood pressure. Am J Physiol Renal Physiol 2013; 304:F1231-42. [PMID: 23515717 DOI: 10.1152/ajprenal.00557.2012] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Tumor necrosis factor-α (TNF-α) is a pleiotropic cytokine that becomes elevated in chronic inflammatory states such as hypertension and diabetes and has been found to mediate both increases and decreases in blood pressure. High levels of TNF-α decrease blood pressure, whereas moderate increases in TNF-α have been associated with increased NaCl retention and hypertension. The explanation for these disparate effects is not clear but could simply be due to different concentrations of TNF-α within the kidney, the physiological status of the subject, or the type of stimulus initiating the inflammatory response. TNF-α alters renal hemodynamics and nephron transport, affecting both activity and expression of transporters. It also mediates organ damage by stimulating immune cell infiltration and cell death. Here we will summarize the available findings and attempt to provide plausible explanations for such discrepancies.
Collapse
Affiliation(s)
- Vanesa D Ramseyer
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, Detroit, MI 48202, USA.
| | | |
Collapse
|
31
|
Hao S, Bellner L, Ferreri NR. NKCC2A and NFAT5 regulate renal TNF production induced by hypertonic NaCl intake. Am J Physiol Renal Physiol 2012; 304:F533-42. [PMID: 23269645 DOI: 10.1152/ajprenal.00243.2012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Pathways that contribute to TNF production by the kidney are not well defined. Mice given 1% NaCl in the drinking water for 3 days exhibited a 2.5-fold increase in urinary, but not plasma, TNF levels compared with mice given tap water. Since furosemide attenuated the increase in TNF levels, we hypothesized that hypertonic NaCl intake increases renal TNF production by a pathway involving the Na(+)-K(+)-2Cl(-) cotransporter (NKCC2). A 2.5-fold increase in NKCC2A mRNA accumulation was observed in medullary thick ascending limb (mTAL) tubules from mice given 1% NaCl; a concomitant 2-fold increase in nuclear factor of activated T cells 5 (NFAT5) mRNA and protein expression was observed in the outer medulla. Urinary TNF levels were reduced in mice given 1% NaCl after an intrarenal injection of a lentivirus construct designed to specifically knockdown NKCC2A (EGFP-N2A-ex4); plasma levels of TNF did not change after injection of EGFP-N2A-ex4. Intrarenal injection of EGFP-N2A-ex4 also inhibited the increase of NFAT5 mRNA abundance in the outer medulla of mice given 1% NaCl. TNF production by primary cultures of mTAL cells increased approximately sixfold in response to an increase in osmolality to 400 mosmol/kgH2O produced with NaCl and was inhibited in cells transiently transfected with a dnNFAT5 construct. Transduction of cells with EGFP-N2A-ex4 also prevented increases in TNF mRNA and protein production in response to high NaCl concentration and reduced transcriptional activity of a NFAT5 promoter construct. Since NKCC2A expression is restricted to the TAL, NKCC2A-dependent activation of NFAT5 is part of a pathway by which the TAL produces TNF in response to hypertonic NaCl intake.
Collapse
Affiliation(s)
- Shoujin Hao
- Dept. of Pharmacology, New York Medical College, Valhalla, NY 10595, USA
| | | | | |
Collapse
|
32
|
Toka HR, Al-Romaih K, Koshy JM, DiBartolo S, Kos CH, Quinn SJ, Curhan GC, Mount DB, Brown EM, Pollak MR. Deficiency of the calcium-sensing receptor in the kidney causes parathyroid hormone-independent hypocalciuria. J Am Soc Nephrol 2012; 23:1879-90. [PMID: 22997254 DOI: 10.1681/asn.2012030323] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Rare loss-of-function mutations in the calcium-sensing receptor (Casr) gene lead to decreased urinary calcium excretion in the context of parathyroid hormone (PTH)-dependent hypercalcemia, but the role of Casr in the kidney is unknown. Using animals expressing Cre recombinase driven by the Six2 promoter, we generated mice that appeared grossly normal but had undetectable levels of Casr mRNA and protein in the kidney. Baseline serum calcium, phosphorus, magnesium, and PTH levels were similar to control mice. When challenged with dietary calcium supplementation, however, these mice had significantly lower urinary calcium excretion than controls (urinary calcium to creatinine, 0.31±0.03 versus 0.63±0.14; P=0.001). Western blot analysis on whole-kidney lysates suggested an approximately four-fold increase in activated Na(+)-K(+)-2Cl(-) cotransporter (NKCC2). In addition, experimental animals exhibited significant downregulation of Claudin14, a negative regulator of paracellular cation permeability in the thick ascending limb, and small but significant upregulation of Claudin16, a positive regulator of paracellular cation permeability. Taken together, these data suggest that renal Casr regulates calcium reabsorption in the thick ascending limb, independent of any change in PTH, by increasing the lumen-positive driving force for paracellular Ca(2+) transport.
Collapse
Affiliation(s)
- Hakan R Toka
- Division of Nephrology, Beth Israel Medical Center, 330 Brookline Avenue, Boston, MA 02115, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Battula S, Hao S, Pedraza PL, Stier CT, Ferreri NR. Tumor necrosis factor-alpha induces renal cyclooxygenase-2 expression in response to hypercalcemia. Prostaglandins Other Lipid Mediat 2012; 99:45-50. [PMID: 22800939 DOI: 10.1016/j.prostaglandins.2012.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 06/29/2012] [Accepted: 07/06/2012] [Indexed: 01/01/2023]
Abstract
The effect of tumor necrosis factor-alpha (TNF) on cyclooxygenase-2 (COX-2) expression in the renal outer medulla (OM) was determined in a model of dihydrotachysterol (DHT)-induced hypercalcemia. Increases in serum calcium and water intake were observed during ingestion of a DHT-containing diet in both wild type (WT) and TNF deficient mice (TNF(-/-)). Polyuria and a decrease in body weight were observed in response to DHT treatment in WT and TNF(-/-) mice. A transient elevation in urinary TNF was observed in WT mice treated with DHT. Moreover, increased urinary levels of prostaglandin E(2) (PGE(2)) and a corresponding increase in COX-2 expression in the OM were observed in WT mice fed DHT. Increased COX-2 expression was not observed in TNF(-/-) mice fed DHT, and the characteristics of PGE(2) synthesis were distinct from those in WT mice. This study demonstrates that COX-2 expression in the OM, secondary to hypercalemia, is TNF-dependent.
Collapse
Affiliation(s)
- Sailaja Battula
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, United States
| | | | | | | | | |
Collapse
|
34
|
Vio CP, Quiroz-Munoz M, Cuevas CA, Cespedes C, Ferreri NR. Prostaglandin E2 EP3 receptor regulates cyclooxygenase-2 expression in the kidney. Am J Physiol Renal Physiol 2012; 303:F449-57. [PMID: 22622465 DOI: 10.1152/ajprenal.00634.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Cyclooxygenase-2 (COX-2) is constitutively expressed and highly regulated in the thick ascending limb (TAL). As COX-2 inhibitors (Coxibs) increase COX-2 expression, we tested the hypothesis that a negative feedback mechanism involving PGE(2) EP3 receptors regulates COX-2 expression in the TAL. Sprague-Dawley rats were treated with a Coxib [celecoxib (20 mg·kg(-1)·day(-1)) or rofecoxib (10 mg·kg(-1)·day(-1))], with or without sulprostone (20 μg·kg(-1)·day(-1)). Sulprostone was given using two protocols, namely, previous to Coxib treatment (prevention effect; Sulp7-Coxib5 group) and 5 days after initiation of Coxib treatment (regression effect; Coxib10-Sulp5 group). Immunohistochemical and morphometric analysis revealed that the stained area for COX-2-positive TAL cells (μm(2)/field) increased in Coxib-treated rats (Sham: 412 ± 56.3, Coxib: 794 ± 153.3). The Coxib effect was inhibited when sulprostone was used in either the prevention (285 ± 56.9) or regression (345 ± 51.1) protocols. Western blot analysis revealed a 2.1 ± 0.3-fold increase in COX-2 protein expression in the Coxib-treated group, an effect abolished by sulprostone using either the prevention (1.2 ± 0.3-fold) or regression (0.6 ± 0.4-fold vs. control, P < 0.05) protocols. Similarly, the 6.4 ± 0.6-fold increase in COX-2 mRNA abundance induced by Coxibs (P < 0.05) was inhibited by sulprostone; prevention: 0.9 ± 0.3-fold (P < 0.05) and regression: 0.6 ± 0.1 (P < 0.05). Administration of a selective EP3 receptor antagonist, L-798106, also increased the area for COX-2-stained cells, COX-2 mRNA accumulation, and protein expression in the TAL. Collectively, the data suggest that COX-2 levels are regulated by a novel negative feedback loop mediated by PGE(2) acting on its EP3 receptor in the TAL.
Collapse
Affiliation(s)
- Carlos P Vio
- Dept. of Physiology, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Alameda 340, Santiago, Chile.
| | | | | | | | | |
Collapse
|
35
|
Ferreri NR, Hao S, Pedraza PL, Escalante B, Vio CP. Eicosanoids and tumor necrosis factor-alpha in the kidney. Prostaglandins Other Lipid Mediat 2011; 98:101-6. [PMID: 22101002 DOI: 10.1016/j.prostaglandins.2011.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 10/31/2011] [Accepted: 11/03/2011] [Indexed: 12/14/2022]
Abstract
The thick ascending limb of Henle's loop (TAL) is capable of metabolizing arachidonic acid (AA) by cytochrome P450 (CYP450) and cyclooxygenase (COX) pathways and has been identified as a nephron segment that contributes to salt-sensitive hypertension. Previous studies demonstrated a prominent role for CYP450-dependent metabolism of AA to products that inhibited ion transport pathways in the TAL. However, COX-2 is constitutively expressed along all segments of the TAL and is increased in response to diverse stimuli. The ability of Tamm-Horsfall glycoprotein, a selective marker of cortical TAL (cTAL) and medullary (mTAL), to bind TNF and localize it to this nephron segment prompted studies to determine the capacity of mTAL cells to produce TNF and determine its effects on mTAL function. The colocalization of calcium-sensing receptor (CaR) and COX-2 in the TAL supports the notion that activation of CaR induces TNF-dependent COX-2 expression and PGE₂ synthesis in mTAL cells. Additional studies showed that TNF produced by mTAL cells inhibits ⁸⁶Rb uptake, an in vitro correlate of natriuresis, in an autocrine- and COX-2-dependent manner. The molecular mechanism for these effects likely includes inhibition of Na⁺-K⁺-2Cl⁻ cotransporter (NKCC2) expression and trafficking.
Collapse
Affiliation(s)
- Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, USA.
| | | | | | | | | |
Collapse
|