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Majid DSA, Prieto MC, Castillo A, Chamberlain C, Navar LG. Augmentation of Nitric Oxide Deficient Hypertension by High Salt Diet Is Associated With Reduced TNF-α Receptor Type 1 Expression in the Kidneys. Am J Hypertens 2024; 37:717-725. [PMID: 38780971 PMCID: PMC11322281 DOI: 10.1093/ajh/hpae066] [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: 12/13/2023] [Revised: 03/26/2024] [Accepted: 05/13/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND High salt (HS) intake induces an augmented hypertensive response to nitric oxide (NO) inhibition, though it causes minimal changes in blood pressure (BP) in NO intact condition. The cause of such augmentation is not known. HS induces tumor necrosis factor-alpha (TNFα) production that causes natriuresis via activation of its receptor type 1 (TNFR1). We hypothesized that NO deficiency reduces renal TNFR1 activity, leading to enhanced sodium retention and hypertension. METHODS We examined the changes in renal TNFR1 protein expression (Immunohistochemistry analyses) after HS (4% NaCl) intake in wild-type mice (WT, C57BL6) treated with a NO synthase (NOS) inhibitor, nitro-l-arginine methyl ester (L-NAME; 0.05 mg/min/g; osmotic mini-pump), as well as in endothelial NOS knockout mice (eNOSKO) and compared the responses in WT mice with normal salt (NS; 0.3% NaCl) intake. BP was measured with tail-cuff plethysmography and 24-hour urine collections were made using metabolic cages. RESULTS HS alone did not alter mean BP in untreated mice (76 ± 3 to 77 ± 1 mm Hg) but induced an augmented response in L-NAME treated (106 ± 1 vs. 97 ± 2 mm Hg) and in eNOSKO (107 ± 2 vs. 89 ± 3 mm Hg) mice. The percentage area of TNFR1 expression in renal tissue was higher in WT + HS (4.1 + 0.5%) than in WT + NS mice (2.7 ± 0.6%). However, TNFR1 expression was significantly lower in L-NAME treated WT + NS (0.9 ± 0.1%) and in eNOSKO + NS (1.4 ± 0.2%) than in both WT + NS and WT + HS mice. CONCLUSIONS These data indicate that TNFR1 activity is downregulated in NO deficient conditions, which facilitates salt retention leading to augmented hypertension during HS intake.
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Affiliation(s)
- Dewan S A Majid
- Department of Physiology, Tulane Hypertension & Renal Center of Excellence, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA
| | - Minolfa C Prieto
- Department of Physiology, Tulane Hypertension & Renal Center of Excellence, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA
| | - Alexander Castillo
- Department of Physiology, Tulane Hypertension & Renal Center of Excellence, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA
| | - Cameron Chamberlain
- Department of Physiology, Tulane Hypertension & Renal Center of Excellence, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA
| | - Luis Gabriel Navar
- Department of Physiology, Tulane Hypertension & Renal Center of Excellence, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA
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Xiong S, Lin S, Hu Y, Xia W, Wang Q, Wang L, Cao T, Liao Y, Scholze A, Tepel M, Zhu Z, Liu D. Dietary Cinnamaldehyde Activation of TRPA1 Antagonizes High-Salt-Induced Hypertension Through Restoring Renal Tubular Mitochondrial Dysfunction. Am J Hypertens 2024; 37:708-716. [PMID: 38820173 DOI: 10.1093/ajh/hpae068] [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: 01/17/2024] [Revised: 03/25/2024] [Accepted: 05/13/2024] [Indexed: 06/02/2024] Open
Abstract
BACKGROUND The renal proximal tubule (RPT) plays a pivotal role in regulating sodium reabsorption and thus blood pressure (BP). Transient receptor potential ankyrin 1 (TRPA1) has been reported to protect against renal injury by modulating mitochondrial function. We hypothesize that the activation of TRPA1 by its agonist cinnamaldehyde may mitigate high-salt intake-induced hypertension by inhibiting urinary sodium reabsorption through restoration of renal tubular epithelial mitochondrial function. METHODS Trpa1-deficient (Trpa1-/-) mice and wild-type (WT) mice were fed standard laboratory chow [normal diet (ND) group, 0.4% salt], standard laboratory chow with 8% salt [high-salt diet (HS) group], or standard laboratory chow with 8% salt plus 0.015% cinnamaldehyde [high-salt plus cinnamaldehyde diet (HSC) group] for 6 months. Urinary sodium excretion, reactive oxygen species (ROS) production, mitochondrial function, and the expression of sodium hydrogen exchanger isoform 3 (NHE3) and Na+/K+-ATPase of RPTs were determined. RESULTS Chronic dietary cinnamaldehyde supplementation reduced tail systolic BP and 24-hour ambulatory arterial pressure in HS-fed WT mice. Compared with the mice fed HS, cinnamaldehyde supplementation significantly increased urinary sodium excretion, inhibited excess ROS production, and alleviated mitochondrial dysfunction of RPTs in WT mice. However, these effects of cinnamaldehyde were absent in Trpa1-/- mice. Furthermore, chronic dietary cinnamaldehyde supplementation blunted HS-induced upregulation of NHE3 and Na+/K+-ATPase in WT mice but not Trpa1-/- mice. CONCLUSIONS The present study demonstrated that chronic activation of Trpa1 attenuates HS-induced hypertension by inhibiting urinary sodium reabsorption through restoring renal tubular epithelial mitochondrial function. Renal TRPA1 may be a potential target for the management of excessive dietary salt intake-associated hypertension.
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Affiliation(s)
- Shiqiang Xiong
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Shaoyang Lin
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Yingru Hu
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Weijie Xia
- Department of Plastic & Cosmetic Surgery, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Qianran Wang
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Lijuan Wang
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Tingbing Cao
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Yingying Liao
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Alexandra Scholze
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark, and Department of Cardiothoracic and Vascular Surgery, Odense University Hospital, Odense, Denmark
| | - Martin Tepel
- Department of Nephrology, Odense University Hospital, Odense, Denmark
- Institute of Molecular Medicine, Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark
- Institute of Clinical Research, University of Southern
| | - Zhiming Zhu
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Daoyan Liu
- Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Army Medical University, Chongqing Institute of Hypertension, Chongqing, China
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Majid DSA, Castillo A, Prieto MC, Navar LG. High salt induced augmentation of angiotensin II mediated hypertension is associated with differential expression of tumor necrosis factor-alpha receptors in the kidney. EXPLORATION OF MEDICINE 2022. [DOI: 10.37349/emed.2022.00086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Aim: Chronic high salt (HS) intake causes minimal changes in blood pressure (BP) but it induces augmented hypertensive response to angiotensin II (AngII) administration in rodents. The mechanism of this augmentation is not clearly understood. As tumor necrosis factor-alpha (TNF-α) induces natriuresis by activating TNF-α receptor type 1 (TNFR1) but not type 2 (TNFR2), we hypothesize that TNFR1 activity is reduced when HS is given in combination of AngII that leads to enhanced sodium retention and thus, causing augmented hypertension. The aim of this study is to examine the responses to chronic HS intake and AngII administration on the renal tissue protein expressions of TNFR1 and TNFR2 in mice.
Methods: Different groups of mice (n = 6–7 in each group) chronically treated with or without AngII (25 ng/min; implanted minipump) for 4 weeks which were fed either normal salt (NS; 0.4% NaCl) or high salt (HS; 4% NaCl) diets. Systemic BP was measured by tail-cuff plethysmography. At the end of treatment period, kidneys were harvested after sacrificing the mice with euthanasia. Immuno-histochemical analysis of TNFR1 and TNFR2 proteins in renal tissues was performed by measuring the staining area and the intensity of receptors’ immunoreactivities using NIS-Elements software. The results were expressed in percent area of positive staining and the relative intensity.
Results: HS intake alone did not alter mean BP (HS; 77 ± 1 vs. NS; 76 ± 3 vs. mmHg; tail-cuff plethysmography) but AngII induced increases in BP were augmented in HS group (104 ± 2 vs. 95 ± 2 mmHg; P < 0.05). The area of TNFR1 staining was higher in HS than NS group (6.0 ± 0.9% vs. 3.2 ± 0.7%; P < 0.05) but it was lower in AngII + HS than in AngII + NS group (5.0 ± 0.7% vs. 6.3 ± 0.7%; P = 0.068). TNFR2 immunoreactivity was minimal in NS and HS groups but it was high in AngII + NS and even higher in AngII + HS group.
Conclusions: These data suggest that the HS induced increased TNFR1 activity that facilitates enhanced sodium excretion is compromised in elevated AngII condition leading to salt retention and augmented hypertension.
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Affiliation(s)
- Dewan S. A. Majid
- Department of Physiology, Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Alexander Castillo
- Department of Physiology, Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Minolfa C. Prieto
- Department of Physiology, Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - L. Gabriel Navar
- Department of Physiology, Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112, USA
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d'Uscio LV, Katusic ZS. Endothelium-specific deletion of amyloid-β precursor protein exacerbates endothelial dysfunction induced by aging. Aging (Albany NY) 2021; 13:19165-19185. [PMID: 34382945 PMCID: PMC8386539 DOI: 10.18632/aging.203401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 07/30/2021] [Indexed: 01/03/2023]
Abstract
The physiological function of amyloid precursor protein (APP) in the control of endothelial function during aging is unclear. Aortas of young (4-6 months old) and aged (23-26 months old) wild-type (WT) and endothelium-specific APP-deficient (eAPP−/−) mice were used to study aging-induced changes in vascular phenotype. Unexpectedly, aging significantly increased protein expression of APP in aortas of WT mice but not in aortas of eAPP−/− mice thereby demonstrating selective upregulation APP expression in vascular endothelium of aged aortas. Most notably, endothelial dysfunction (impairment of endothelium-dependent relaxations) induced by aging was significantly exacerbated in aged eAPP−/− mice aortas as compared to age-matched WT mice. Consistent with this observations, endothelial nitric oxide synthase (eNOS) protein expression was significantly decreased in aged eAPP−/− mice as compared to age matched WT mice. In addition, protein expression of cyclooxygenase 2 and release of prostaglandins were significantly increased in both aged WT and eAPP−/− mice. Notably, treatment with cyclooxygenase inhibitor, indomethacin, normalized endothelium-dependent relaxations in aged WT mice, but not in aged eAPP−/− mice. In aggregate, our findings support the concept that aging-induced upregulation of APP in vascular endothelium is an adaptive response designed to protect and preserve expression and function of eNOS.
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Affiliation(s)
- Livius V d'Uscio
- Departments of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN 55902, USA
| | - Zvonimir S Katusic
- Departments of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN 55902, USA
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5
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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.
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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
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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
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6
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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.
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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
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7
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Kim HY, Choi HS, Kim CS, Bae EH, Ma SK, Sung SA, Han SH, Oh KH, Ahn C, Kim SW. Effect of urinary angiotensinogen and high-salt diet on blood pressure in patients with chronic kidney disease: results from the Korean Cohort Study for Outcome in Patients with Chronic Kidney Disease (KNOW-CKD). Korean J Intern Med 2021; 36:659-667. [PMID: 33028070 PMCID: PMC8137406 DOI: 10.3904/kjim.2020.077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 04/23/2020] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND/AIMS This study aimed to investigate whether urinary angiotensinogen (UAGT) excretion was associated with elevated blood pressure in patients with chronic kidney disease (CKD) and to evaluate the relationship among blood pressure, intra-renal renin-angiotensin system (RAS) activity, and dietary sodium in patients with CKD. METHODS Participants from the Korean Cohort Study for Outcome in Patients with Chronic Kidney Disease (KNOW-CKD) were included. Of the total cohort of 2,238 individuals with CKD, we included 1,955 participants who underwent complete 24-hour urinary sodium (24-hour UNa) analysis. They were categorized into three groups according to three tertiles of their 24-hour UNa, reflecting daily salt intake. To measure intra-renal RAS activity, the UAGT excretion was assayed with an enzyme-linked immunosorbent assay. RESULTS Elevated 24-hour UNa levels, logarithm of UAGT-to-creatinine ratio (UAGT/Cr), increased waist-to-hip ratio, and decreased estimated glomerular filtration rate were the risk factors for increased systolic blood pressure. Systolic blood pressure showed a positive correlation with 24-hour UNa levels and logarithm of UAGT/Cr. CONCLUSION UAGT and urinary sodium excretion are independent determinants of systolic blood pressure in patients with CKD. These findings suggest that increased systolic blood pressure in CKD patients is associated with both increased dietary sodium levels and intra-renal RAS activity. The risk of elevated systolic blood pressure in the 3rd tertile of both the UAGT/Cr and 24-hour UNa groups was about 2.3 times higher than that in the reference group.
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Affiliation(s)
- Ha Yeon Kim
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Hong Sang Choi
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Chang Seong Kim
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Eun Hui Bae
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Seong Kwon Ma
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Su-Ah Sung
- Department of Internal Medicine, Nowon Eulji Medical Center, Eulji University, Seoul, Korea
| | - Seung Hyeok Han
- Department of Internal Medicine and Institute of Kidney Disease Research, Yonsei University College of Medicine, Seoul, Korea
| | - Kook-Hwan Oh
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Curie Ahn
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Soo Wan Kim
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea
- Correspondence to Soo Wan Kim, M.D. Department of Internal Medicine, Chonnam National University Medical School, 42 Jebong-ro, Dong-gu, Gwangju 61469, Korea Tel: +82-62-220-6271, Fax: +82-62-225-8578 E-mail:
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Wu J, Fang S, Lu KT, Wackman K, Schwartzman ML, Dikalov SI, Grobe JL, Sigmund CD. EP3 (E-Prostanoid 3) Receptor Mediates Impaired Vasodilation in a Mouse Model of Salt-Sensitive Hypertension. Hypertension 2021; 77:1399-1411. [PMID: 33641369 DOI: 10.1161/hypertensionaha.120.16518] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Jing Wu
- From the Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee (J.W., S.F., K.-T.L., K.W., J.L.G., C.D.S.)
| | - Shi Fang
- From the Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee (J.W., S.F., K.-T.L., K.W., J.L.G., C.D.S.).,Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa (S.F.)
| | - Ko-Ting Lu
- From the Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee (J.W., S.F., K.-T.L., K.W., J.L.G., C.D.S.)
| | - Kelsey Wackman
- From the Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee (J.W., S.F., K.-T.L., K.W., J.L.G., C.D.S.)
| | - Michal L Schwartzman
- Department of Pharmacology, New York Medical College School of Medicine, Valhalla (M.L.S.)
| | - Sergey I Dikalov
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (S.D.)
| | - Justin L Grobe
- From the Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee (J.W., S.F., K.-T.L., K.W., J.L.G., C.D.S.)
| | - Curt D Sigmund
- From the Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee (J.W., S.F., K.-T.L., K.W., J.L.G., C.D.S.)
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9
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Singh P, Stephenson R, Castillo A, Majid DSA. High-salt intake reduces renal tissue levels of inflammatory cytokines in mice. Physiol Rep 2021; 8:e14621. [PMID: 33345460 PMCID: PMC7750173 DOI: 10.14814/phy2.14621] [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: 08/06/2020] [Revised: 09/28/2020] [Accepted: 10/01/2020] [Indexed: 12/24/2022] Open
Abstract
High salt (HS) intake is usually considered as an aggravating factor to induce inflammatory renal injury. However, the changes in the renal levels of inflammatory cytokines during HS intake is not yet clearly defined. We hypothesize that HS increases renal levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) but decreases interleukin-10 (IL-10; anti-inflammatory cytokine) and these responses exacerbate in NO deficient conditions. Both wild-type (WT) and endothelial NO synthase knockout (eNOSKO) mice (~8 weeks old, n = 6 in each group) were given normal-salt (NS; 0.3% NaCl) and HS (4% NaCl) containing diets for 2 weeks. Systolic blood pressure (SBP) was determined by tail-cuff plethysmography and urine collections were made using metabolic cages. Basal SBP was higher in eNOSKO than WT mice (131 ± 7 vs 117 ± 3 mmHg; p < .05). HS intake for 2 weeks increased SBP in eNOSKO (161 ± 5 mmHg) but not in WT mice. In NS groups, the cytokine levels in renal tissues (measured using ELISA kits and expressed in pg/mg protein) were significantly higher in eNOSKO than WT mice (TNF-α, 624 ± 67 vs. 325 ± 73; IL-6, 619 ± 106 vs. 166 ± 61; IL-10, 6,087 ± 567 vs. 3,929 ± 378). Interestingly, these cytokine levels in HS groups were significantly less both in WT (TNF-α, 114 ± 17; IL-6, 81 ± 14; IL-10, 865 ± 130) and eNOSKO (TNF-α, 115 ± 18; IL-6, 56 ± 7; IL-10, 882 ± 141) mice. These findings indicate that HS induces downregulation of cytokines in the kidney. Such HS-induced reduction in cytokines, particularly TNF-α (a natriuretic agent), would facilitate more salt-retention, and thus, leading to salt-sensitive hypertension in NO deficient conditions.
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Affiliation(s)
- Purnima Singh
- Department of Physiology, Hypertension and Renal Centre of ExcellenceTulane University School of MedicineNew OrleansLAUSA
| | - Roxan Stephenson
- Department of Physiology, Hypertension and Renal Centre of ExcellenceTulane University School of MedicineNew OrleansLAUSA
| | - Alexander Castillo
- Department of Physiology, Hypertension and Renal Centre of ExcellenceTulane University School of MedicineNew OrleansLAUSA
| | - Dewan S. A. Majid
- Department of Physiology, Hypertension and Renal Centre of ExcellenceTulane University School of MedicineNew OrleansLAUSA
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10
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Wang C, Kawakami-Mori F, Kang L, Ayuzawa N, Ogura S, Koid SS, Reheman L, Yeerbolati A, Liu B, Yatomi Y, Chen X, Fujita T, Shimosawa T. Low-dose L-NAME induces salt sensitivity associated with sustained increased blood volume and sodium-chloride cotransporter activity in rodents. Kidney Int 2020; 98:1242-1252. [PMID: 32592815 DOI: 10.1016/j.kint.2020.05.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 05/18/2020] [Accepted: 05/21/2020] [Indexed: 12/01/2022]
Abstract
To investigate the cause of salt sensitivity in a normotensive animal model, we treated rats with a low-dose of the nitric oxide synthase inhibitor, L-NAME, that does not elevate blood pressure per se or induce kidney fibrosis. A high salt diet increased the circulating blood volume both in L-NAME-treated and nontreated animals for the first 24 hours. Thereafter, the blood volume increase persisted only in the L-NAME-treated rats. Blood pressure was higher in the L-NAME-treated group from the start of high salt diet exposure. Within the first 24 hours of salt loading, the L-NAME treated animals failed to show vasodilation and maintained high systemic vascular resistance in response to blood volume expansion. After four weeks on the high salt diet, the slope of the pressure-natriuresis curve was blunted in the L-NAME-treated group. An increase in natriuresis was observed after treatment with hydrochlorothiazide, but not amiloride, a change observed in parallel with increased phosphorylated sodium-chloride cotransporter (NCC). In contrast, a change in blood pressure was not observed in L-NAME-treated NCC-deficient mice fed a high salt diet. Moreover, direct L-NAME-induced NCC activation was demonstrated in cells of the mouse distal convoluted tubule. The vasodilatator, sodium nitroprusside, downregulated phosphorylated NCC expression. The effect of L-NAME on phosphorylated NCC was blocked by both the SPAK inhibitor STOCK2S-26016 and the superoxide dismutase mimetic TEMPO which also attenuated salt-induced hypertension. These results suggest that the initiation of salt sensitivity in normotensive rodents could be due to hyporeactivity of the vasculature and that maintaining blood pressure could result in a high circulating volume due to inappropriate NCC activity in the low-dose L-NAME model. Thus, even slightly impaired nitric oxide production may be important in salt sensitivity regulation in healthy rodents.
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Affiliation(s)
- Conghui Wang
- Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; Department of Clinical Laboratory, School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Fumiko Kawakami-Mori
- Department of Clinical Epigenetics, Research Center for Advancing Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Lei Kang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, China
| | - Nobuhiro Ayuzawa
- Department of Clinical Epigenetics, Research Center for Advancing Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Sayoko Ogura
- Department of Pathology and Microbiology, Division of Laboratory Medicine, School of Medicine, Nihon University, Tokyo, Japan
| | - Suang Suang Koid
- Department of Clinical Laboratory, School of Medicine, The University of Tokyo, Tokyo, Japan; Department of Clinical Laboratory, School of Medicine, International University of Health and Welfare, Chiba, Japan
| | - Latapati Reheman
- Department of Clinical Laboratory, School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Alimila Yeerbolati
- Department of Clinical Laboratory, School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Beibei Liu
- Department of Clinical Laboratory, School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yutaka Yatomi
- Department of Clinical Laboratory, School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Xiangmei Chen
- Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China
| | - Toshiro Fujita
- Department of Clinical Epigenetics, Research Center for Advancing Science and Technology, The University of Tokyo, Tokyo, Japan; CREST, Japan Science and Technology Agency, Tokyo, Japan
| | - Tatsuo Shimosawa
- Department of Clinical Laboratory, School of Medicine, International University of Health and Welfare, Chiba, Japan; CREST, Japan Science and Technology Agency, Tokyo, Japan.
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11
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Cuevas S, Asico LD, Jose PA, Konkalmatt P. Renal Hydrogen Peroxide Production Prevents Salt-Sensitive Hypertension. J Am Heart Assoc 2020; 9:e013818. [PMID: 31902320 PMCID: PMC6988155 DOI: 10.1161/jaha.119.013818] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 12/05/2019] [Indexed: 02/07/2023]
Abstract
Background The regulation of sodium excretion is important in the pathogenesis of hypertension and salt sensitivity is predictive of cardiovascular events and mortality. C57Bl/6 and BALB/c mice have different blood pressure sensitivities to salt intake. High salt intake increases blood pressure in some C57Bl/6J mouse strains but not in any BALB/c mouse strain. Methods and Results We determined the cause of the difference in salt sensitivity between C57Bl/6 and BALB/c mice. Basal levels of superoxide and H2O2 were higher in renal proximal tubule cells (RPTCs) from BALB/c than C57Bl/6J mice. High salt diet increased H2O2 production in kidneys from BALB/c but C57Bl/6J mice. High sodium concentration (170 mmol/L) in the incubation medium increased H2O2 levels in BALB/c-RPTCs but not in C57Bl/6J-RPTCs. H2O2 (10 μmol/L) treatment decreased sodium transport in RPTCs from BALB/c but not C57Bl/6J mice. Overexpression of catalase in the mouse kidney predisposed BALB/c mice to salt-sensitive hypertension. Conclusions Our data show that the level of salt-induced H2O2 production negatively regulates RPTC sodium transport and determines the state of salt sensitivity in 2 strains of mice. High concentrations of antioxidants could prevent H2O2 production in renal proximal tubules, which would result in sodium retention and increased blood pressure.
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Affiliation(s)
- Santiago Cuevas
- Division of Renal Diseases & HypertensionDepartment of MedicineThe George Washington University School of Medicine and Health SciencesWashingtonDC
| | - Laureano D. Asico
- Division of Renal Diseases & HypertensionDepartment of MedicineThe George Washington University School of Medicine and Health SciencesWashingtonDC
| | - Pedro A. Jose
- Division of Renal Diseases & HypertensionDepartment of MedicineThe George Washington University School of Medicine and Health SciencesWashingtonDC
| | - Prasad Konkalmatt
- Division of Renal Diseases & HypertensionDepartment of MedicineThe George Washington University School of Medicine and Health SciencesWashingtonDC
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12
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Xue H, Geurts AM, Usa K, Wang F, Lin Y, Phillips J, Henderson L, Baker MA, Tian Z, Liang M. Fumarase Overexpression Abolishes Hypertension Attributable to endothelial NO synthase Haploinsufficiency in Dahl Salt-Sensitive Rats. Hypertension 2019; 74:313-322. [PMID: 31230549 DOI: 10.1161/hypertensionaha.119.12723] [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: 12/29/2022]
Abstract
Human blood pressure salt sensitivity is associated with changes in urinary metabolites related to fumarase (Fh) and nitric oxide (NO) metabolism, and fumarase promotes NO production through an arginine regeneration pathway. We examined the role of the fumarase-NO pathway in the development of hypertension using genetically engineered rat models. Dahl salt-sensitive (SS) rats with heterozygous mutation of eNOS (endothelial NO synthase or Nos3; SS-Nos3+/-) were bred with SS rats with a hemizygous Fh transgene. SS-Nos3+/- rats without the Fh transgene (SS-Nos3+/-/Fh0/0) developed substantial hypertension with a mean arterial pressure of 134.2±3.7 mm Hg on a 0.4% NaCl diet and 178.0±3.5 mm Hg after 14 days on a 4% NaCl diet. Mean arterial pressure decreased remarkably to 123.1±1.4 mm Hg on 0.4% NaCl, and 143.3±1.5 mm Hg on 4% NaCl in SS-Nos3+/- rats with a Fh transgene (SS-Nos3+/-/Fh0/1), and proteinuria, renal fibrosis, and tubular casts were attenuated in SS-Nos3+/-/Fh0/1 rats compared with SS-Nos3+/-/Fh0/0 rats. eNOS protein abundance decreased in rats with the Nos3 heterozygous mutation, which was not influenced by Fh overexpression in rats on the 0.4% NaCl diet. However, the decrease in NO metabolite in the renal outer medulla of SS-Nos3+/-/Fh0/0 rats on the 0.4% NaCl diet was reversed in SS-Nos3+/-/Fh0/1 rats, and levels of L-arginine, but not the other 12 amino acids analyzed, were significantly higher in SS-Nos3+/-/Fh0/1 rats than in SS-Nos3+/+/Fh0/0 rats. In conclusion, fumarase has potent effects in restoring NO production and blunting the development of hypertension attributable to eNOS haploinsufficiency.
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Affiliation(s)
- Hong Xue
- From the Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, China (H.X.).,Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.)
| | - Aron M Geurts
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.).,Genomic Sciences and Precision Medicine Center Medical College of Wisconsin, Milwaukee (A.M.G.)
| | - Kristie Usa
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.)
| | - Feng Wang
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.).,Department of Nephrology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, China (F.W., Y.L.)
| | - Yingying Lin
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.).,Department of Nephrology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, China (F.W., Y.L.)
| | - Jenifer Phillips
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.)
| | - Lisa Henderson
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.)
| | - Maria Angeles Baker
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.)
| | - Zhongmin Tian
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, China (Z.T.)
| | - Mingyu Liang
- Center of Systems Molecular Medicine, Department of Physiology (H.X., A.M.G., K.U., F.W., Y.L., J.P., L.H., M.A.B., M.L.)
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13
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Nishimoto M, Mizuno R, Fujita T, Isshiki M. Stromal interaction molecule 1 modulates blood pressure via NO production in vascular endothelial cells. Hypertens Res 2018; 41:506-514. [DOI: 10.1038/s41440-018-0045-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/08/2018] [Accepted: 01/14/2018] [Indexed: 01/19/2023]
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14
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Singh P, Castillo A, Islam MT, Majid DSA. Evidence for Prohypertensive, Proinflammatory Effect of Interleukin-10 During Chronic High Salt Intake in the Condition of Elevated Angiotensin II Level. Hypertension 2017; 70:839-845. [PMID: 28847894 DOI: 10.1161/hypertensionaha.117.09401] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 03/30/2017] [Accepted: 07/07/2017] [Indexed: 12/31/2022]
Abstract
IL-10 (interleukin-10) has been suggested to play a protective role in angiotensin II (AngII)-induced cardiovascular disorders. This study examined the role of endogenous IL-10 in salt-sensitive hypertension and renal injury induced by AngII. Responses to chronic AngII (400 ng/min per kilogram body weight; osmotic minipump) infusion were evaluated in IL-10 gene knockout mice fed with either normal salt diet (0.3% NaCl) or high salt (HS; 4% NaCl) diet, and these responses were compared with those in wild-type mice. Normal salt diets or HS diets were given alone for the first 2 weeks and then with AngII treatment for an additional 2 weeks (n=6 in each group). Arterial pressure was continuously monitored by implanted radio-telemetry, and a 24-hour urine collection was performed by metabolic cages on the last day of the experimental period. Basal mean arterial pressure was lower in IL-10 gene knockout mice than in wild-type (98±3 versus 113±3 mm Hg) mice. Mean arterial pressure responses to normal salt/HS alone or to the AngII+normal salt treatment were similar in both strains. However, the increase in mean arterial pressure induced by the AngII+HS treatment was significantly lower in IL-10 gene knockout mice (15±5% versus 37±3%) compared with wild-type mice. Renal tissue endothelial nitric oxide synthase expression (≈3-folds) and urinary excretion of nitric oxide metabolites, nitrate/nitrite (1.2±0.1 versus 0.2±0.02 µmol/L/24 hours) were higher in IL-10 gene knockout mice compared with wild-type mice. These results indicate that an increase in nitric oxide production helps to mitigate salt-sensitive hypertension induced by AngII and suggest that a compensatory interaction between IL-10 and nitric oxide exists in modulating AngII-induced responses during HS intake.
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Affiliation(s)
- Purnima Singh
- From the Department of Physiology, Tulane University School of Medicine, New Orleans, LA
| | - Alexander Castillo
- From the Department of Physiology, Tulane University School of Medicine, New Orleans, LA
| | - M Toriqul Islam
- From the Department of Physiology, Tulane University School of Medicine, New Orleans, LA
| | - Dewan S A Majid
- From the Department of Physiology, Tulane University School of Medicine, New Orleans, LA.
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15
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Nakai K, Fujii H, Kono K, Goto S, Nishi S. Hypertension Induced by Tyrosine-Kinase Inhibitors for the Treatment of Renal Cell Carcinoma in Hemodialysis Patients: A Single-Center Experience and Review of the Literature. Ther Apher Dial 2017; 21:320-325. [DOI: 10.1111/1744-9987.12537] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 01/25/2017] [Accepted: 01/27/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Kentaro Nakai
- Division of Nephrology and Kidney Center; Kobe University Graduate School of Medicine; Kobe Japan
- Department of Nephrology and Kidney Center; Kakogawa Central City Hospital; Kakogawa Japan
| | - Hideki Fujii
- Division of Nephrology and Kidney Center; Kobe University Graduate School of Medicine; Kobe Japan
| | - Keiji Kono
- Division of Nephrology and Kidney Center; Kobe University Graduate School of Medicine; Kobe Japan
| | - Shunsuke Goto
- Division of Nephrology and Kidney Center; Kobe University Graduate School of Medicine; Kobe Japan
| | - Shinichi Nishi
- Division of Nephrology and Kidney Center; Kobe University Graduate School of Medicine; Kobe Japan
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16
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Yan Y, Shapiro AP, Mopidevi BR, Chaudhry MA, Maxwell K, Haller ST, Drummond CA, Kennedy DJ, Tian J, Malhotra D, Xie ZJ, Shapiro JI, Liu J. Protein Carbonylation of an Amino Acid Residue of the Na/K-ATPase α1 Subunit Determines Na/K-ATPase Signaling and Sodium Transport in Renal Proximal Tubular Cells. J Am Heart Assoc 2016; 5:e003675. [PMID: 27613772 PMCID: PMC5079028 DOI: 10.1161/jaha.116.003675] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 08/12/2016] [Indexed: 01/12/2023]
Abstract
BACKGROUND We have demonstrated that cardiotonic steroids, such as ouabain, signaling through the Na/K-ATPase, regulate sodium reabsorption in the renal proximal tubule. By direct carbonylation modification of the Pro222 residue in the actuator (A) domain of pig Na/K-ATPase α1 subunit, reactive oxygen species are required for ouabain-stimulated Na/K-ATPase/c-Src signaling and subsequent regulation of active transepithelial (22)Na(+) transport. In the present study we sought to determine the functional role of Pro222 carbonylation in Na/K-ATPase signaling and sodium handling. METHODS AND RESULTS Stable pig α1 knockdown LLC-PK1-originated PY-17 cells were rescued by expressing wild-type rat α1 and rat α1 with a single mutation of Pro224 (corresponding to pig Pro222) to Ala. This mutation does not affect ouabain-induced inhibition of Na/K-ATPase activity, but abolishes the effects of ouabain on Na/K-ATPase/c-Src signaling, protein carbonylation, Na/K-ATPase endocytosis, and active transepithelial (22)Na(+) transport. CONCLUSIONS Direct carbonylation modification of Pro224 in the rat α1 subunit determines ouabain-mediated Na/K-ATPase signal transduction and subsequent regulation of renal proximal tubule sodium transport.
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Affiliation(s)
- Yanling Yan
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV
| | - Anna P Shapiro
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Brahma R Mopidevi
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Muhammad A Chaudhry
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV
| | - Kyle Maxwell
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV
| | - Steven T Haller
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | | | - David J Kennedy
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Jiang Tian
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Deepak Malhotra
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Zi-Jian Xie
- Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV
| | - Joseph I Shapiro
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Jiang Liu
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV
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17
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Itani HA, Xiao L, Saleh MA, Wu J, Pilkinton MA, Dale BL, Barbaro NR, Foss JD, Kirabo A, Montaniel KR, Norlander AE, Chen W, Sato R, Navar LG, Mallal SA, Madhur MS, Bernstein KE, Harrison DG. CD70 Exacerbates Blood Pressure Elevation and Renal Damage in Response to Repeated Hypertensive Stimuli. Circ Res 2016; 118:1233-43. [PMID: 26988069 DOI: 10.1161/circresaha.115.308111] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 03/17/2016] [Indexed: 01/11/2023]
Abstract
RATIONALE Accumulating evidence supports a role of adaptive immunity and particularly T cells in the pathogenesis of hypertension. Formation of memory T cells, which requires the costimulatory molecule CD70 on antigen-presenting cells, is a cardinal feature of adaptive immunity. OBJECTIVE To test the hypothesis that CD70 and immunologic memory contribute to the blood pressure elevation and renal dysfunction mediated by repeated hypertensive challenges. METHODS AND RESULTS We imposed repeated hypertensive challenges using either N(ω)-nitro-L-arginine methyl ester hydrochloride (L-NAME)/high salt or repeated angiotensin II stimulation in mice. During these challenges effector memory T cells (T(EM)) accumulated in the kidney and bone marrow. In the L-NAME/high-salt model, memory T cells of the kidney were predominant sources of interferon-γ and interleukin-17A, known to contribute to hypertension. L-NAME/high salt increased macrophage and dendritic cell surface expression of CD70 by 3- to 5-fold. Mice lacking CD70 did not accumulate T(EM) cells and did not develop hypertension to either high salt or the second angiotensin II challenge and were protected against renal damage. Bone marrow-residing T(EM) cells proliferated and redistributed to the kidney in response to repeated salt feeding. Adoptively transferred T(EM) cells from hypertensive mice homed to the bone marrow and spleen and expanded on salt feeding of the recipient mice. CONCLUSIONS Our findings illustrate a previously undefined role of CD70 and long-lived T(EM) cells in the development of blood pressure elevation and end-organ damage that occur on delayed exposure to mild hypertensive stimuli. Interventions to prevent repeated hypertensive surges could attenuate formation of hypertension-specific T(EM) cells.
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Affiliation(s)
- Hana A Itani
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Liang Xiao
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Mohamed A Saleh
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Jing Wu
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Mark A Pilkinton
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Bethany L Dale
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Natalia R Barbaro
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Jason D Foss
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Annet Kirabo
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Kim R Montaniel
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Allison E Norlander
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Wei Chen
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Ryosuke Sato
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - L Gabriel Navar
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Simon A Mallal
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Meena S Madhur
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - Kenneth E Bernstein
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA
| | - David G Harrison
- From the Division of Clinical Pharmacology, Department of Medicine (H.A.I., L.X., M.A.S., J.W., B.L.D., J.D.F., A.K., K.R.M., A.E.N., W.C., M.S.M., D.G.H.) and Division of Infectious Diseases (M.A.P., S.A.M.), Vanderbilt University Medical Center, Nashville, TN; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt (M.A.S.); Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil (N.R.B.); Department of Physiology and Hypertension and Renal Center, School of Medicine, Tulane University, New Orleans, LA (R.S., L.G.N.); and Departments of Biomedical Sciences (K.E.B.) and Pathology and Laboratory Medicine (K.E.B.), Cedars-Sinai Medical Center, Los Angeles, CA.
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18
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Chaston DJ, Haddock RE, Howitt L, Morton SK, Brown RD, Matthaei KI, Hill CE. Perturbation of chemical coupling by an endothelial Cx40 mutant attenuates endothelium-dependent vasodilation by KCa channels and elevates blood pressure in mice. Pflugers Arch 2015; 467:1997-2009. [PMID: 25369777 DOI: 10.1007/s00424-014-1640-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/16/2014] [Accepted: 10/21/2014] [Indexed: 10/24/2022]
Abstract
Mutant forms of connexin40 (Cx40) exist in the human population and predispose carriers to atrial fibrillation. Since endothelial expression of Cx40 is important for electrical and chemical communication within the arterial wall, carriers of mutant Cx40 proteins may be predisposed to peripheral arterial dysfunction and dysregulation of blood pressure. We have therefore studied mice expressing either a chemically dysfunctional mutant, Cx40T202S, or wild-type Cx40, with native Cx40, specifically in the endothelium. Blood pressure was measured by telemetry under normal conditions and during cardiovascular stress induced by locomotor activity, phenylephrine or nitric oxide blockade (N(ɷ)-nitro-L-arginine methyl ester hydroxide, L-NAME). Blood pressure of Cx40T202STg mice was significantly elevated at night when compared with wild-type or Cx40Tg mice, without change in mean heart rate, pulse pressure or locomotor activity. Analysis over 24 h showed that blood pressure of Cx40T202STg mice was significantly elevated at rest and additionally during locomotor activity. In contrast, neither plasma renin concentration nor pressor responses to phenylephrine or L-NAME were altered, the latter indicating that nitric oxide bioavailability was normal. In isolated, pressurised mesenteric arteries, hyperpolarisation and vasodilation evoked by SKA-31, the selective modulator of SKCa and IKCa channels, was significantly reduced in Cx40T202STg mice, due to attenuation of the SKCa component. Acetylcholine-induced ascending vasodilation in vivo was also significantly attenuated in cremaster muscle arterioles of Cx40T202STg mice, compared to wild-type and Cx40Tg mice. We conclude that endothelial expression of the chemically dysfunctional Cx40T202S reduces peripheral vasodilator capacity mediated by SKCa-dependent hyperpolarisation and also increases blood pressure.
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Affiliation(s)
- Daniel J Chaston
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, 0200, Australia
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19
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Kopkan L, Husková Z, Jíchová Š, Červenková L, Červenka L, Saifudeen Z, El-Dahr SS. Conditional knockout of collecting duct bradykinin B2 receptors exacerbates angiotensin II-induced hypertension during high salt intake. Clin Exp Hypertens 2015; 38:1-9. [PMID: 26151827 DOI: 10.3109/10641963.2015.1047945] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
We elucidated the role of collecting duct kinin B2 receptor (B2R) in the development of salt-sensitivity and angiotensin II (ANG II)-induced hypertension. To this end, we used a Cre-Lox recombination strategy to generate mice lacking Bdkrb2 gene for B2R in the collecting duct (Hoxb7-Cre(tg/+):Bdkrb2(flox/flox)). In 3 groups of control (Bdkrb2(flox/flox)) and 3 groups of UB(Bdkrb2-/-) mice, systolic blood pressure (SBP) responses to high salt intake (4 or 8% NaCl; HS) were monitored by radiotelemetry in comparison with standard salt diet (0.4% NaCl) prior to and during subcutaneous ANG II infusion (1000 ng/min/kg) via osmotic minipumps. High salt intakes alone for 2 weeks did not alter SBP in either strain. ANG II significantly increased SBP equally in control (121 ± 2 to 156 ± 3 mmHg) and UB(Bdkrb2-/-) mice (120 ± 2 to 153 ± 2 mmHg). The development of ANG II-induced hypertension was exacerbated by 4%HS in both control (125 ± 3 to 164 ± 5 mmHg) and UB(Bdkrb2-/-) mice (124 ± 2 to 162 ± 3 mmHg) during 2 weeks. Interestingly, 8%HS caused a more profound and earlier ANG II-induced hypertension in UB(Bdkrb2-/-) (129 ± 2 to 166 ± 3 mmHg) as compared to control (128 ± 2 to 158 ± 2 mmHg) and it was accompanied by body weight loss and increased mortality. In conclusion, targeted inactivation of B2R in the renal collecting duct does not cause salt-sensitivity; however, collecting duct B2R attenuates the hypertensive actions of ANG II under conditions of very high salt intake.
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Affiliation(s)
- Libor Kopkan
- a Center of Experimental Medicine, Institute for Clinical and Experimental Medicine , Prague , Czech Republic
| | - Zuzana Husková
- a Center of Experimental Medicine, Institute for Clinical and Experimental Medicine , Prague , Czech Republic
| | - Šárka Jíchová
- a Center of Experimental Medicine, Institute for Clinical and Experimental Medicine , Prague , Czech Republic
| | - Lenka Červenková
- a Center of Experimental Medicine, Institute for Clinical and Experimental Medicine , Prague , Czech Republic
| | - Luděk Červenka
- a Center of Experimental Medicine, Institute for Clinical and Experimental Medicine , Prague , Czech Republic .,b Department of Pathophysiology, 2nd Faculty of Medicine , Charles University , Prague , Czech Republic , and
| | - Zubaida Saifudeen
- c Department of Pediatrics , Tulane University School of Medicine , New Orleans , LA , USA
| | - Samir S El-Dahr
- c Department of Pediatrics , Tulane University School of Medicine , New Orleans , LA , USA
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Majid DSA, Prieto MC, Navar LG. Salt-Sensitive Hypertension: Perspectives on Intrarenal Mechanisms. Curr Hypertens Rev 2015; 11:38-48. [PMID: 26028244 DOI: 10.2174/1573402111666150530203858] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 04/22/2015] [Accepted: 04/24/2015] [Indexed: 12/12/2022]
Abstract
Salt sensitive hypertension is characterized by increases in blood pressure in response to increases in dietary salt intake and is associated with an enhanced risk of cardiovascular and renal morbidity. Although researchers have sought for decades to understand how salt sensitivity develops in humans, the mechanisms responsible for the increases in blood pressure in response to high salt intake are complex and only partially understood. Until now, scientists have been unable to explain why some individuals are salt sensitive and others are salt resistant. Although a central role for the kidneys in the development of salt sensitivity and hypertension has been generally accepted, it is also recognized that hypertension is of multifactorial origin and a variety of factors can induce, or prevent, blood pressure responsiveness to the manipulation of salt intake. Excess salt intake in susceptible persons may also induce inappropriate central and sympathetic nervous system responses and increase the production of intrarenal angiotensin II, catecholamines and other factors such as oxidative stress and inflammatory cytokines. One key factor is the concomitant inappropriate or paradoxical activation of the intrarenal renin-angiotensin system, by high salt intake. This is reflected by the increases in urinary angiotensinogen during high salt intake in salt sensitive models. A complex interaction between neuroendocrine factors and the kidney may underlie the propensity for some individuals to retain salt and develop salt-dependent hypertension. In this review, we focus mainly on the renal contributions that provide the mechanistic links between chronic salt intake and the development of hypertension.
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Affiliation(s)
- Dewan S A Majid
- Department of Physiology, SL39, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
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21
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Kim SM, Mizel D, Qin Y, Huang Y, Schnermann J. Blood pressure, heart rate and tubuloglomerular feedback in A1AR-deficient mice with different genetic backgrounds. Acta Physiol (Oxf) 2015; 213:259-67. [PMID: 25182861 DOI: 10.1111/apha.12377] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 07/28/2014] [Accepted: 08/27/2014] [Indexed: 01/11/2023]
Abstract
AIM Differences in genetic background between control mice and mice with targeted gene mutations have been recognized as a potential cause for phenotypic differences. In this study, we have used A1AR-deficient mice in a C57Bl/6 and SWR/J congenic background to assess the influence of background on the effect of A1AR-deficiency on cardiovascular and renal functional parameters. METHODS In A1AR+/+ and A1AR-/- mice in C57Bl/6 and SWR/J congenic backgrounds, we assessed blood pressure and heart rate using radio-telemetry, plasma renin concentrations and tubuloglomerular feedback. RESULTS We did not detect significant differences in arterial blood pressure (MAP) and heart rates (HR) between A1AR+/+ and A1AR-/- mice in either C57Bl/6, SWR/J or mixed backgrounds. MAP and HR were significantly higher in SWR/J than in C57Bl/6 mice. A high NaCl intake increased MAP in A1AR-/- mice on C57Bl/6 background while there was less or no salt sensitivity in the SWR/J background. No significant differences in plasma renin concentration were detected between A1AR-/- and A1AR+/+ mice in any of the strains. Tubuloglomerular feedback was found to be absent in A1AR-/- mice with SWR/J genetic background. CONCLUSIONS While this study confirmed important differences between inbred mouse strains, we did not identify phenotypic modifications of A1AR-related effects on blood pressure, heart rate and plasma renin by differences in genetic background.
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Affiliation(s)
- S. M. Kim
- Department of Physiology; Chonbuk National University Medical School; Jeonju South Korea
- National Institute of Diabetes and Digestive and Kidney Diseases; NIH; Bethesda Maryland
| | - D. Mizel
- National Institute of Diabetes and Digestive and Kidney Diseases; NIH; Bethesda Maryland
| | - Y. Qin
- National Institute of Diabetes and Digestive and Kidney Diseases; NIH; Bethesda Maryland
| | - Y. Huang
- National Institute of Diabetes and Digestive and Kidney Diseases; NIH; Bethesda Maryland
| | - J. Schnermann
- National Institute of Diabetes and Digestive and Kidney Diseases; NIH; Bethesda Maryland
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22
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Khan AE, Scheelbeek PFD, Shilpi AB, Chan Q, Mojumder SK, Rahman A, Haines A, Vineis P. Salinity in drinking water and the risk of (pre)eclampsia and gestational hypertension in coastal Bangladesh: a case-control study. PLoS One 2014; 9:e108715. [PMID: 25268785 PMCID: PMC4182542 DOI: 10.1371/journal.pone.0108715] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 09/03/2014] [Indexed: 11/18/2022] Open
Abstract
Background Hypertensive disorders in pregnancy are among the leading causes of maternal and perinatal death in low-income countries, but the aetiology remains unclear. We investigated the relationship between salinity in drinking water and the risk of (pre)eclampsia and gestational hypertension in a coastal community. Methods A population-based case-control study was conducted in Dacope, Bangladesh among 202 pregnant women with (pre)eclampsia or gestational hypertension, enrolled from the community served by the Upazilla Health Complex, Dacope and 1,006 matched controls from the same area. Epidemiological and clinical data were obtained from all participants. Urinary sodium and sodium levels in drinking water were measured. Logistic regression was used to calculate odds ratios, and 95% confidence intervals. Findings Drinking water sources had exceptionally high sodium levels (mean 516.6 mg/L, S.D 524.2). Women consuming tube-well (groundwater) were at a higher disease risk than rainwater users (p<0.001). Adjusted risks for (pre)eclampsia and gestational hypertension considered together increased in a dose-response manner for increasing sodium concentrations (300.01–600 mg/L, 600.1–900 mg/L, >900.01 mg/L, compared to <300 mg/L) in drinking water (ORs 3.30 [95% CI 2.00–5.51], 4.40 [2.70–7.25] and 5.48 [3.30–9.11] (p-trend<0.001). Significant associations were seen for both (pre)eclampsia and gestational hypertension separately. Interpretation Salinity in drinking water is associated with increased risk of (pre)eclampsia and gestational hypertension in this population. Given that coastal populations in countries such as Bangladesh are confronted with high salinity exposure, which is predicted to further increase as a result of sea level rise and other environmental influences, it is imperative to develop and evaluate affordable approaches to providing water with low salt content.
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Affiliation(s)
- Aneire Ehmar Khan
- MRC-HPA Centre for Environment and Health and Dept. of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
- Grantham Institute for Climate Change, Imperial College London, London, United Kingdom
- * E-mail:
| | - Pauline Franka Denise Scheelbeek
- MRC-HPA Centre for Environment and Health and Dept. of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | | | - Queenie Chan
- MRC-HPA Centre for Environment and Health and Dept. of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | | | - Atiq Rahman
- Bangladesh Center for Advanced Studies, Dhaka, Bangladesh
| | - Andy Haines
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Paolo Vineis
- MRC-HPA Centre for Environment and Health and Dept. of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
- Grantham Institute for Climate Change, Imperial College London, London, United Kingdom
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23
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Preston RA, Afshartous D, Materson BJ, Rodco R, Alonso AB. Effects of Nebivolol Versus Metoprolol on Sodium Sensitivity and Renal Sodium Handling in Hypertensive Hispanic Postmenopausal Women. Hypertension 2014; 64:287-95. [DOI: 10.1161/hypertensionaha.114.03476] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Richard A. Preston
- From the Clinical Pharmacology Research Unit, Division of Clinical Pharmacology, Department of Medicine, Miller School of Medicine, University of Miami, FL (R.A.P., D.A., B.J.M., R.R., A.B.A.); Jackson Memorial Hospital, Miami, FL (R.A.P.); Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL (R.A.P.); Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN (D.A.); and Department of Analytics,
| | - David Afshartous
- From the Clinical Pharmacology Research Unit, Division of Clinical Pharmacology, Department of Medicine, Miller School of Medicine, University of Miami, FL (R.A.P., D.A., B.J.M., R.R., A.B.A.); Jackson Memorial Hospital, Miami, FL (R.A.P.); Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL (R.A.P.); Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN (D.A.); and Department of Analytics,
| | - Barry J. Materson
- From the Clinical Pharmacology Research Unit, Division of Clinical Pharmacology, Department of Medicine, Miller School of Medicine, University of Miami, FL (R.A.P., D.A., B.J.M., R.R., A.B.A.); Jackson Memorial Hospital, Miami, FL (R.A.P.); Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL (R.A.P.); Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN (D.A.); and Department of Analytics,
| | - Rolando Rodco
- From the Clinical Pharmacology Research Unit, Division of Clinical Pharmacology, Department of Medicine, Miller School of Medicine, University of Miami, FL (R.A.P., D.A., B.J.M., R.R., A.B.A.); Jackson Memorial Hospital, Miami, FL (R.A.P.); Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL (R.A.P.); Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN (D.A.); and Department of Analytics,
| | - Alberto B. Alonso
- From the Clinical Pharmacology Research Unit, Division of Clinical Pharmacology, Department of Medicine, Miller School of Medicine, University of Miami, FL (R.A.P., D.A., B.J.M., R.R., A.B.A.); Jackson Memorial Hospital, Miami, FL (R.A.P.); Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL (R.A.P.); Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN (D.A.); and Department of Analytics,
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Canale D, de Bragança AC, Gonçalves JG, Shimizu MHM, Sanches TR, Andrade L, Volpini RA, Seguro AC. Vitamin D deficiency aggravates nephrotoxicity, hypertension and dyslipidemia caused by tenofovir: role of oxidative stress and renin-angiotensin system. PLoS One 2014; 9:e103055. [PMID: 25048368 PMCID: PMC4105615 DOI: 10.1371/journal.pone.0103055] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 06/25/2014] [Indexed: 02/05/2023] Open
Abstract
Vitamin D deficiency (VDD) is prevalent among HIV-infected individuals. Vitamin D has been associated with renal and cardiovascular diseases because of its effects on oxidative stress, lipid metabolism and renin-angiotensin-aldosterone system (RAAS). Tenofovir disoproxil fumarate (TDF), a widely used component of antiretroviral regimens for HIV treatment, can induce renal injury. The aim of this study was to investigate the effects of VDD on TDF-induced nephrotoxicity. Wistar rats were divided into four groups: control, receiving a standard diet for 60 days; VDD, receiving a vitamin D-free diet for 60 days; TDF, receiving a standard diet for 60 days with the addition of TDF (50 mg/kg food) for the last 30 days; and VDD+TDF receiving a vitamin D-free diet for 60 days with the addition of TDF for the last 30 days. TDF led to impaired renal function, hyperphosphaturia, hypophosphatemia, hypertension and increased renal vascular resistance due to downregulation of the sodium-phosphorus cotransporter and upregulation of angiotensin II and AT1 receptor. TDF also increased oxidative stress, as evidenced by higher TBARS and lower GSH levels, and induced dyslipidemia. Association of TDF and VDD aggravated renovascular effects and TDF-induced nephrotoxicity due to changes in the redox state and involvement of RAAS.
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Affiliation(s)
- Daniele Canale
- Nephrology Department, University of São Paulo School of Medicine, São Paulo, Brazil
| | | | | | | | - Talita Rojas Sanches
- Nephrology Department, University of São Paulo School of Medicine, São Paulo, Brazil
| | - Lúcia Andrade
- Nephrology Department, University of São Paulo School of Medicine, São Paulo, Brazil
| | | | - Antonio Carlos Seguro
- Nephrology Department, University of São Paulo School of Medicine, São Paulo, Brazil
- * E-mail:
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Crestani S, Gasparotto Júnior A, Marques MCA, Sullivan JC, Webb RC, da Silva-Santos JE. Enhanced angiotensin-converting enzyme activity and systemic reactivity to angiotensin II in normotensive rats exposed to a high-sodium diet. Vascul Pharmacol 2013; 60:67-74. [PMID: 24321189 DOI: 10.1016/j.vph.2013.12.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 11/24/2013] [Accepted: 12/01/2013] [Indexed: 10/25/2022]
Abstract
A high salt diet is associated with reduced activity of the renin-angiotensin-aldosterone system (RAAS). However, normotensive rats exposed to high sodium do not show changes in systemic arterial pressure. We hypothesized that, despite the reduced circulating amounts of angiotensin II induced by a high salt diet, the cardiovascular system's reactivity to angiotensin II is increased in vivo, contributing to maintain arterial pressure at normal levels. Male Wistar rats received chow containing 0.27% (control), 2%, 4%, or 8% NaCl for six weeks. The high-sodium diet did not lead to changes in arterial pressure, although plasma levels of angiotensin II and aldosterone were reduced in the 4% and 8% NaCl groups. The 4% and 8% NaCl groups showed enhanced pressor responses to angiotensin I and II, accompanied by unchanged and increased angiotensin-converting enzyme activity, respectively. The 4% NaCl group showed increased expression of angiotensin II type 1 receptors and reduced expression of angiotensin II type 2 receptors in the aorta. In addition, the hypotensive effect of losartan was reduced in both 4% and 8% NaCl groups. In conclusion these results explain, at least in part, why the systemic arterial pressure is maintained at normal levels in non-salt sensitive and healthy rats exposed to a high salt diet, when the functionality of RAAS appears to be blunted, as well as suggest that angiotensin II has a crucial role in the vascular dysfunction associated with high salt intake, even in the absence of hypertension.
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Affiliation(s)
- Sandra Crestani
- Department of Pharmacology, Universidade Federal do Paraná, Curitiba, PR, Brazil; Department of Physiology, Georgia Health Sciences University, Augusta, GA, USA
| | | | - Maria C A Marques
- Department of Pharmacology, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Jennifer C Sullivan
- Department of Medicine, Georgia Health Sciences University, Augusta, GA, USA
| | - R Clinton Webb
- Department of Physiology, Georgia Health Sciences University, Augusta, GA, USA
| | - J Eduardo da Silva-Santos
- Department of Pharmacology, Universidade Federal do Paraná, Curitiba, PR, Brazil; Laboratory of Cardiovascular Pharmacology, Department of Pharmacology, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
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Whiting C, Castillo A, Haque MZ, Majid DSA. Protective role of the endothelial isoform of nitric oxide synthase in ANG II-induced inflammatory responses in the kidney. Am J Physiol Renal Physiol 2013; 305:F1031-41. [PMID: 23926180 DOI: 10.1152/ajprenal.00024.2013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
In the present study, we examine the hypothesis that the nitric oxide (NO) produced by endothelial NO synthase (eNOS) plays a protective role in the development of ANG II-induced hypertension and renal injury by minimizing oxidative stress and the inflammation induced by TNF-α. Systolic blood pressure (SBP) and renal injury responses to chronic infusions of ANG II (via implanted minipumps) were evaluated for 2 wk in wild-type (WT) and in eNOS knockout mice (KO) cotreated with or without a superoxide (O2(-)) scavenger, tempol (400 mg/l in the drinking water), or a TNF-α receptor blocker, etanercept (5 mg/kg/day ip). In study 1, when ANG II was given at a dose of 25 ng/min, it increased mean SBP in WT mice (Δ36 ± 3 mmHg; n = 7), and this effect was attenuated in mice pretreated with tempol (Δ24 ± 3 mmHg; n = 6). In KO mice (n = 9), this dose of ANG II resulted in severe renal injury associated with high mortality. To avoid this high mortality in KO, study 2 was conducted with a lower dose of ANG II (10 ng/min) that increased SBP slightly in WT (Δ17 ± 7 mmHg; n = 6) but exaggeratedly in KO (Δ48 ± 12 mmHg, n = 6) associated with severe renal injury. Cotreatment with either tempol (n = 6) or etanercept (n = 6) ameliorated the hypertensive, as well as the renal injury responses in KO compared with WT. These data demonstrate a protective role for eNOS activity in preventing renal inflammatory injury and hypertension induced by chronic increases in ANG II.
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Affiliation(s)
- Curtis Whiting
- Dept. of Physiology, Hypertension and Renal Center of Excellence, Tulane Univ. Health Sciences Center, New Orleans, LA 70112, USA.
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Antihypertensive and renoprotective actions of soluble epoxide hydrolase inhibition in ANG II-dependent malignant hypertension are abolished by pretreatment with L-NAME. J Hypertens 2013; 31:321-32. [PMID: 23307303 DOI: 10.1097/hjh.0b013e32835b50aa] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE The present study was performed to investigate in a model of malignant hypertension if the antihypertensive actions of soluble epoxide hydrolase (sEH) inhibition are nitric oxide (NO)-dependent. METHODS ANG II-dependent malignant hypertension was induced through dietary administration for 3 days of the natural xenobiotic indole-3-carbinol (I3C) in Cyp1a1-Ren-2 transgenic rats. Blood pressure (BP) was monitored by radiotelemetry and treatment with the sEH inhibitor [cis-4-[4-(3-adamantan-1-yl-ureido)-cyclohexyl-oxy]-benzoic acid (c-AUCB)] was started 48 h before administration of the diet containing I3C. In separate groups of rats, combined administration of the sEH inhibitor and the nonspecific NO synthase inhibitor [Nω-nitro-L-arginine methyl ester (L-NAME)] on the course of BP in I3C-induced and noninduced rats were evaluated. In addition, combined blockade of renin-angiotensin system (RAS) was superimposed on L-NAME administration in separate groups of rats. After 3 days of experimental protocols, the rats were prepared for renal functional studies and renal concentrations of epoxyeicosatrienoic acids (EETs) and their inactive metabolites dihydroxyeicosatrienoic acids (DHETEs) were measured. RESULTS Treatment with c-AUCB increased the renal EETs/DHETEs ratio, attenuated the increases in BP, and prevented the decreases in renal function and the development of renal damage in I3C-induced Cyp1a1-Ren-2 rats. The BP lowering and renoprotective actions of the treatment with the sEH inhibitor c-AUCB were completely abolished by concomitant administration of L-NAME and not fully rescued by double RAS blockade without altering the increased EETs/DHETEs ratio. CONCLUSION Our current findings indicate that the antihypertensive actions of sEH inhibition in this ANG II-dependent malignant form of hypertension are dependent on the interactions of endogenous bioavailability of EETs and NO.
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Stec DE, Storm MV, Pruett BE, Gousset MU. Antihypertensive actions of moderate hyperbilirubinemia: role of superoxide inhibition. Am J Hypertens 2013; 26:918-23. [PMID: 23482378 DOI: 10.1093/ajh/hpt038] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Moderate (approximately 2-fold) increases in plasma unconjugated bilirubin levels are able to attenuate the development of angiotensin II (Ang II)-dependent hypertension. To determine the specific role of decreases in superoxide production to the blood pressure-lowering effects of moderate hyperbilirubinemia (MHyB), we performed this study, in which the Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor apocynin was given to Ang II-infused mice in the presence and absence of moderate hyperbilirubinemia. METHODS Apocynin (14mM) was administered in the drinking water prior to treatment with UDP-glucuronosyltransferase 1A1 antisense morpholino (16 μg/kg), which was administered by intravenous injection every third day. Treatments were started before the implantation of Ang II-containing minipumps (1μg/kg/min) and continued throughout the protocol. RESULTS Ang II infusion increased blood pressure to 145±2mm Hg. Apocynin treatment alone reduced blood pressure to 135±5mm Hg, whereas MHyB alone decreased blood pressure to 118±5mm Hg in Ang II-infused mice. Prior inhibition of NADPH oxidase with apocynin did not result in a further decrease in blood pressure in MHyB mice, which averaged 117±3mm Hg (n = 6 mice per group). In aortic preparations, apocynin treatment decreased Ang II-mediated superoxide production from 2433±120 relative light units (RLU)/min/mg to 1851±126 RLU/min/mg (n = 4 mice per group), which was similar to levels observed in MHyB mice alone (1473±132 RLU/min/mg) or in combination with apocynin (1503±115 RLU/min/mg). CONCLUSIONS Our results indicate that MHyB lowers blood pressure by a mechanism that is partially dependent on the inhibition of superoxide production.
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Affiliation(s)
- David E Stec
- Department of Physiology & Biophysics, Center for Excellence in Cardiovascular-Renal Research, University of Mississippi Medical Center, Jackson, Mississippi, USA.
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Impaired pressure natriuresis is associated with interstitial inflammation in salt-sensitive hypertension. Curr Opin Nephrol Hypertens 2013; 22:37-44. [PMID: 23165109 DOI: 10.1097/mnh.0b013e32835b3d54] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
PURPOSE OF REVIEW Impairment of the pressure natriuresis relationship is a central event in the pathogenesis of hypertension. Renal tubulointerstitial inflammation results in salt-sensitive hypertension and, until recently, the changes in pressure natriuresis induced by renal inflammation received little attention. RECENT FINDINGS Oxidative stress and increased intrarenal angiotensin II activity, in association with rarefaction and loss of peritubular vascular network, may be involved in the inflammation-induced blunting of the natriuresis resulting from increments in renal perfusion pressure. SUMMARY Here, we review the mechanisms for the impairment in pressure natriuresis resulting from renal tubulointerstitial inflammation in reference to the normal physiologic mechanisms involved in this response.
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Stæhr M, Hansen PBL, Madsen K, Vanhoutte PM, Nüsing RM, Jensen BL. Deletion of cyclooxygenase-2 in the mouse increases arterial blood pressure with no impairment in renal NO production in response to chronic high salt intake. Am J Physiol Regul Integr Comp Physiol 2013; 304:R899-907. [PMID: 23535462 DOI: 10.1152/ajpregu.00103.2012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Experiments were designed to test the hypothesis that cyclooxygenase-2 (COX-2) activity attenuates the blood pressure increase during high NaCl intake by stimulation of endothelial nitric oxide synthase (eNOS)-mediated NO synthesis in the kidney medulla. COX-2(-/-) (C57BL6) an COX-2(+/+) mice were fed a diet with 0.004% (low salt, LS) or 4% (high salt, HS) NaCl for 18 days. Arterial blood pressure was recorded continuously using indwelling catheters. Food and water intake and diuresis were measured in metabolic cages. Urine osmolality and excretion of electrolytes, cGMP, cAMP, and NOx were determined, as well as plasma NOx and cGMP. There was a significant dependence of blood pressure on salt intake and genotype: COX-2(-/-) exhibited higher blood pressure than COX-2(+/+) both on HS and LS intake. COX-2(+/+) littermates displayed an increase in blood pressure on HS versus LS (102.3 ± 1.1 mmHg vs. 91.9 ± 0.9 mmHg) day and night. The mice exhibited significant blood pressure increases during the awake phase (night) that were larger in COX-2(-/-) on HS diet compared with COX-2(+/+). Water intake, diuresis, Na(+), and osmolyte excretions and NOx and cGMP excretions were significantly and similarly elevated with HS in COX-2(-/-) and COX-2(+/+). In summary, C57BL6 mice exhibit a salt intake-dependent increase in arterial blood pressure with increased renal NO production. COX-2 activity has a general lowering effect on arterial blood pressure. COX-2 dampens NaCl-induced increases in arterial blood pressure in the awake phase. In conclusion, COX-2 activity attenuates the changes in nocturnal blood pressure during high salt intake, and COX-2 activity is not necessary for increased renal nitric oxide formation during elevated NaCl intake.
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Affiliation(s)
- Mette Stæhr
- Department of Cardiovascular and Renal Research, University of Southern Denmark, Denmark
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Mechanism of hypertension and proteinuria during angiogenesis inhibition. J Hypertens 2013; 31:444-54; discussion 454. [DOI: 10.1097/hjh.0b013e32835c1d1b] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Singh P, Bahrami L, Castillo A, Majid DSA. TNF-α type 2 receptor mediates renal inflammatory response to chronic angiotensin II administration with high salt intake in mice. Am J Physiol Renal Physiol 2013; 304:F991-9. [PMID: 23389459 DOI: 10.1152/ajprenal.00525.2012] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Tumor necrosis factor-alpha (TNF-α) has been implicated in salt-sensitive hypertension and renal injury (RI) induced by angiotensin II (ANG II). To determine the receptor type of TNF-α involved in this mechanism, we evaluated the responses to chronic ANG II infusion (25 ng/min by implanted minipump) given with high-salt diet (HS; 4% NaCl) for 2 wk in gene knockout mice for TNF-α receptor type 1 (TNFR1KO; n = 6) and type 2 (TNFR2KO; n = 6) and compared the responses with those in wild-type (WT; C57BL/6; n = 6) mice. Blood pressure in these mice was measured by implanted radiotelemetry as well as by tail-cuff plethysmography. RI responses were assessed by measuring macrophage cell infiltration (CD68(+) immunohistochemistry), glomerulosclerosis (PAS staining), and interstitial fibrosis (Gomori's trichrome staining) in renal tissues at the end of the treatment period. The increase in mean arterial pressure induced by ANG II + HS treatment was not different in these three groups of mice (TNFR1KO, 114 ± 1 to 161 ± 7 mmHg; TNFR2KO, 113 ± 1 to 161 ± 3 mmHg; WT, 110 ± 3 to 154 ± 3 mmHg). ANG II + HS-induced RI changes were similar in TNFR1KO mice but significantly less in TNFR2KO mice (macrophage infiltration, 0.02 ± 0.01 vs. 1.65 ± 0.45 cells/mm(2); glomerulosclerosis, 26.3 ± 2.6 vs. 35.7 ± 2.2% area; and interstitial fibrosis, 5.2 ± 0.6 vs. 8.1 ± 1.1% area) compared with the RI changes in WT mice. The results suggest that a direct activation of TNF-α receptors may not be required in inducing hypertensive response to chronic ANG II administration with HS intake, but the induction of inflammatory responses leading to renal injury are mainly mediated by TNF-α receptor type 2.
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Affiliation(s)
- Purnima Singh
- Department of Physiology, Hypertension & Renal Center of Excellence, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
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Kopkan L, Husková Z, Sporková A, Varcabová Š, Honetschlägerová Z, Hwang SH, Tsai HJ, Hammock BD, Imig JD, Kramer HJ, Bürgelová M, Vojtíšková A, Kujal P, Vernerová Z, Červenka L. Soluble epoxide hydrolase inhibition exhibits antihypertensive actions independently of nitric oxide in mice with renovascular hypertension. Kidney Blood Press Res 2012; 35:595-607. [PMID: 22948718 PMCID: PMC3604982 DOI: 10.1159/000339883] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2011] [Accepted: 06/01/2012] [Indexed: 01/13/2023] Open
Abstract
OBJECTIVE The present study was performed to examine whether the blood pressure (BP)-lowering effects of soluble epoxide hydrolase (sEH) inhibition in two-kidney, one-clip (2K1C) Goldblatt hypertension are nitric oxide (NO) dependent. METHODS Mice lacking the endothelial NO synthase (eNOS) gene (eNOS-/-) and their wild-type controls (eNOS+/+) underwent clipping of one renal artery. BP was monitored by radiotelemetry and the treatment with the sEH inhibitor cis-4-[4-(3-adamantan-1-yl-ureido)cyclohex-yloxy]-benzoic acid (c-AUCB) was initiated on day 25 after clipping and lasted for 14 days. Renal concentrations of epoxyeicosatrienoic acids (EETs) and their inactive metabolite dihydroxyeicosatrienoic acids (DHETs) were measured in the nonclipped kidney. Renal NO synthase (NOS) activity was determined by measuring the rate of formation of L-[(14)C]citruline from L-[(14)C]arginine. RESULTS Treatment with the sEH inhibitor elicited similar BP decreases that were associated with increases in daily sodium excretion in 2K1C eNOS+/+ as well as 2K1C eNOS-/- mice. In addition, treatment with the sEH inhibitor increased the ratio of EETs/DHETs in the nonclipped kidney of 2K1C eNOS+/+ as well as 2K1C eNOS-/- mice. Treatment with the sEH inhibitor did not alter renal NOS activity in any of the experimental groups. CONCLUSIONS Collectively, our present data suggest that the BP-lowering effects of chronic sEH inhibition in 2K1C mice are mainly associated with normalization of the reduced availability of biologically active EETs in the nonclipped kidney and their direct natriuretic actions.
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Affiliation(s)
- Libor Kopkan
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Zuzana Husková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Alexandra Sporková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Šárka Varcabová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Zuzana Honetschlägerová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Sung Hee Hwang
- Department of Entomology and UCD Cancer Center, University of California, Davis, One Shields Avenue, Davis, California 95616-8584, USA
| | - Hsing-Ju Tsai
- Department of Entomology and UCD Cancer Center, University of California, Davis, One Shields Avenue, Davis, California 95616-8584, USA
| | - Bruce D. Hammock
- Department of Entomology and UCD Cancer Center, University of California, Davis, One Shields Avenue, Davis, California 95616-8584, USA
| | - John D. Imig
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Wisconsin, USA
| | - Herbert J. Kramer
- Section of Nephrology, Medical Policlinic, Department of Medicine, University of Bonn, Bonn, Germany
| | - Marcela Bürgelová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Alžběta Vojtíšková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Petr Kujal
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Pathology, 3 Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Zdenka Vernerová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Pathology, 3 Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Luděk Červenka
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Physiology, 2 Faculty of Medicine, Charles University, Prague, Czech Republic
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Mechanisms associated to impaired activity of cardiac P-type ATPases in endothelial nitric oxide synthase knockout mice. J Physiol Biochem 2012; 69:207-14. [DOI: 10.1007/s13105-012-0203-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 07/25/2012] [Indexed: 11/26/2022]
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Abstract
PURPOSE OF REVIEW Despite decades of study, the pathogenesis of essential hypertension remains obscure, but the kidney appears to play a central role. Technology for manipulation of the mouse genome has been immensely valuable in dissecting pathways involved in blood pressure control. This review summarizes recent studies employing this technology to understand signaling pathways and specific cell lineages within the kidney that are involved in the regulation of sodium excretion impacting blood pressure homeostasis. RECENT FINDINGS We review a series of recent studies of regulatory pathways affecting sodium excretion by the kidney including the renin-angiotensin system, the mineralocorticoid receptor, the endothelin system, nitric oxide, and the with-no-lysine (K)/sterile 20-like kinase pathway. We have specifically highlighted studies utilizing transgenic mouse models, which provide a powerful mechanism for defining the role of proteins and pathways on sodium balance and blood pressure in the intact organism. SUMMARY These studies underscore the importance of the kidney in regulation of blood pressure and the pathogenesis of hypertension. Transgenic mouse models provide a powerful approach to identifying key cell lineages and molecular pathways causing hypertension. These pathways represent potential targets for novel antihypertensive therapies.
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Reactive Oxygen Species Modulation of Na/K-ATPase Regulates Fibrosis and Renal Proximal Tubular Sodium Handling. Int J Nephrol 2012; 2012:381320. [PMID: 22518311 PMCID: PMC3299271 DOI: 10.1155/2012/381320] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 11/07/2011] [Indexed: 01/11/2023] Open
Abstract
The Na/K-ATPase is the primary force regulating renal sodium handling and plays a key role in both ion homeostasis and blood pressure regulation. Recently, cardiotonic steroids (CTS)-mediated Na/K-ATPase signaling has been shown to regulate fibrosis, renal proximal tubule (RPT) sodium reabsorption, and experimental Dahl salt-sensitive hypertension in response to a high-salt diet. Reactive oxygen species (ROS) are an important modulator of nephron ion transport. As there is limited knowledge regarding the role of ROS-mediated fibrosis and RPT sodium reabsorption through the Na/K-ATPase, the focus of this review is to examine the possible role of ROS in the regulation of Na/K-ATPase activity, its signaling, fibrosis, and RPT sodium reabsorption.
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Balakumar P, Kathuria S, Taneja G, Kalra S, Mahadevan N. Is targeting eNOS a key mechanistic insight of cardiovascular defensive potentials of statins? J Mol Cell Cardiol 2012; 52:83-92. [DOI: 10.1016/j.yjmcc.2011.09.014] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2011] [Accepted: 09/16/2011] [Indexed: 01/14/2023]
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Xue B, Beltz TG, Johnson RF, Guo F, Hay M, Johnson AK. PVN adenovirus-siRNA injections silencing either NOX2 or NOX4 attenuate aldosterone/NaCl-induced hypertension in mice. Am J Physiol Heart Circ Physiol 2011; 302:H733-41. [PMID: 22140041 DOI: 10.1152/ajpheart.00873.2011] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Mineralocorticoid excess increases superoxide production by activating NADPH oxidase (NOX), and intracerebroventricular infusions of NADPH oxidase inhibitors attenuate aldosterone (Aldo)/salt-induced hypertension. It has been hypothesized that increased reactive oxygen species (ROS) in the brain may be a key mechanism in the development of hypertension. The present study investigated the brain regional specificity of NADPH oxidase and the role of NOX2 and NOX4 NADPH oxidase subunits in the hypothalamic paraventricular nucleus (PVN) in Aldo/salt-induced hypertension. PVN injections of adenoviral vectors expressing small interfering (si)RNA targeting NOX2 (AdsiRNA-NOX2) or NOX4 (AdsiRNA-NOX4) mRNAs were used to knock down NOX2 and NOX4 proteins. Three days later, delivery of Aldo (0.2 mg·kg(-1)·day(-1) sc) via osmotic pump commenced and 1% NaCl was provided in place of water. PVN injections of either AdsiRNA-NOX2 or AdsiRNA-NOX4 significantly attenuated the development of Aldo/NaCl-induced hypertension. In an additional study, Aldo/salt-induced hypertension was also significantly attenuated in NOX2 (genomic) knockout mice compared with wild-type controls. When animals from both functional studies underwent ganglionic blockade, there was a reduced fall in blood pressure in the NOX2 and NOX4 knockdown/knockout mice. Western blot analyses of the PVN of siRNA-NOX2- or siRNA-NOX4-injected mice confirmed a marked reduction in the expression of NOX2 or NOX4 protein. In cultured PVN neurons, silencing either NOX2 or NOX4 protein production by culturing PVN cells with siRNA-NOX2 or siRNA-NOX4 attenuated Aldo-induced ROS. These data indicate that both NOX2 and NOX4 in the PVN contribute to elevated sympathetic activity and the hypertensivogenic actions induced by mineralocorticoid excess.
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Affiliation(s)
- Baojian Xue
- Departments of Psychology, University of Iowa, Iowa City, IA 52242, USA.
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Lara LS, McCormack M, Semprum-Prieto LC, Shenouda S, Majid DSA, Kobori H, Navar LG, Prieto MC. AT1 receptor-mediated augmentation of angiotensinogen, oxidative stress, and inflammation in ANG II-salt hypertension. Am J Physiol Renal Physiol 2011; 302:F85-94. [PMID: 21900456 DOI: 10.1152/ajprenal.00351.2011] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Augmentation of intrarenal angiotensinogen (AGT) synthesis, secretion, and excretion is associated with the development of hypertension, renal oxidative stress, and tissue injury during ANG II-dependent hypertension. High salt (HS) exacerbates hypertension and kidney injury, but the mechanisms remain unclear. In this study, we determined the consequences of HS intake alone compared with chronic ANG II infusion and combined HS plus ANG II on the stimulation of urinary AGT (uAGT), renal oxidative stress, and renal injury markers. Sprague-Dawley rats were subjected to 1) a normal-salt diet [NS, n = 5]; 2) HS diet [8% NaCl, n = 5]; 3) ANG II infusion in NS rats [ANG II 80 ng/min, n = 5]; 4) ANG II infusion in HS rats [ANG II+HS, n = 5]; and 5) ANG II infusion in HS rats treated with ANG II type 1 receptor blocker (ARB) [ANG II+HS+ARB, n = 5] for 14 days. Rats fed a HS diet alone did not show changes in systolic blood pressure (SBP), proteinuria, cell proliferation, or uAGT excretion although they did exhibit mesangial expansion, collagen deposition, and had increased NADPH oxidase activity accompanied by increased peroxynitrite formation in the kidneys. Compared with ANG II rats, the combination of ANG II infusion and a HS diet led to exacerbation in SBP (175 ± 10 vs. 221 ± 8 mmHg; P < 0.05), proteinuria (46 ± 7 vs. 127 ± 7 mg/day; P < 0.05), and uAGT (1,109 ± 70 vs.. 7,200 ± 614 ng/day; P < 0.05) associated with greater collagen deposition, mesangial expansion, interstitial cell proliferation, and macrophage infiltration. In both ANG II groups, the O(2)(-) levels were increased due to increased NADPH oxidase activity without concomitant increases in peroxynitrite formation. The responses in ANG II rats were prevented or ameliorated by ARB treatment. The results indicate that HS independently stimulates ROS formation, which may synergize with the effect of ANG II to limit peroxynitrite formation, leading to exacerbation of uAGT and greater injury during ANG II salt hypertension.
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Affiliation(s)
- Lucienne S Lara
- Tulane Univ., School of Medicine, Dept. of Physiology, Rm. 4061, 1430 Tulane Ave., New Orleans, LA 70112, USA
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Kanbay M, Chen Y, Solak Y, Sanders PW. Mechanisms and consequences of salt sensitivity and dietary salt intake. Curr Opin Nephrol Hypertens 2011; 20:37-43. [PMID: 21088577 PMCID: PMC3089903 DOI: 10.1097/mnh.0b013e32834122f1] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE OF REVIEW Investigation into the underlying mechanisms of salt sensitivity has made important advances in recent years. This review examines in particular the effects of sodium and potassium on vascular function. RECENT FINDINGS Sodium chloride (salt) intake promotes cutaneous lymphangiogenesis mediated through tissue macrophages and directly alters endothelial cell function, promoting increased production of transforming growth factor-β (TGF-β) and nitric oxide. In the setting of endothelial dysfunction, such as occurs with aging, diminished nitric oxide production exacerbates the vascular effects of TGF-β, promoting decreased arterial compliance and hypertension. Dietary potassium intake may serve as an important countervailing influence on the effects of salt in the vasculature. SUMMARY There is growing appreciation that, independently of alterations in blood pressure, dietary intake of sodium and potassium promotes functional changes in the vasculature and lymphatic system. These changes may protect against development of salt-sensitive hypertension. While salt sensitivity cannot be ascribed exclusively to these factors, perturbation of these processes promotes hypertension during high-salt intake. These studies add to the list of genetic and environmental factors that are associated with salt sensitivity, but in particular provide insight into adaptive mechanisms during high salt intake.
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Affiliation(s)
- Mehmet Kanbay
- Division of Nephrology, Department of Internal Medicine, Fatih University School of Medicine, Ankara, Turkey
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