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Carullo N, Fabiano G, D'Agostino M, Zicarelli MT, Musolino M, Presta P, Michael A, Andreucci M, Bolignano D, Coppolino G. New Insights on the Role of Marinobufagenin from Bench to Bedside in Cardiovascular and Kidney Diseases. Int J Mol Sci 2023; 24:11186. [PMID: 37446363 DOI: 10.3390/ijms241311186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023] Open
Abstract
Marinobufagenin (MBG) is a member of the bufadienolide family of compounds, which are natural cardiac glycosides found in a variety of animal species, including man, which have different physiological and biochemical functions but have a common action on the inhibition of the adenosine triphosphatase sodium-potassium pump (Na+/K+-ATPase). MBG acts as an endogenous cardiotonic steroid, and in the last decade, its role as a pathogenic factor in various human diseases has emerged. In this paper, we have collated major evidence regarding the biological characteristics and functions of MBG and its implications in human pathology. This review focused on MBG involvement in chronic kidney disease, including end-stage renal disease, cardiovascular diseases, sex and gender medicine, and its actions on the nervous and immune systems. The role of MBG in pathogenesis and the development of a wide range of pathological conditions indicate that this endogenous peptide could be used in the future as a diagnostic biomarker and/or therapeutic target, opening important avenues of scientific research.
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Affiliation(s)
- Nazareno Carullo
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | - Giuseppe Fabiano
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | - Mario D'Agostino
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | | | - Michela Musolino
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | - Pierangela Presta
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | - Ashour Michael
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | - Michele Andreucci
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | - Davide Bolignano
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
| | - Giuseppe Coppolino
- Renal Unit, "Magna Graecia" University of Catanzaro, 88100 Catanzaro, Italy
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2
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Zhu C, Gu W, Sun D, Wei W. The mechanism underlying fluoride-induced low-renin hypertension is related to an imbalance in the circulatory and local renin-angiotensin systems. Toxicol Lett 2023; 381:36-47. [PMID: 37105417 DOI: 10.1016/j.toxlet.2023.04.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/13/2023] [Accepted: 04/24/2023] [Indexed: 04/29/2023]
Abstract
The renin-angiotensin system (RAS) is an important fluid regulation system in the body, and excessive activation of the circulatory or local RAS can increase blood pressure (BP). Excess fluoride can increase BP, although the underlying mechanism related to activation of the RAS remains unclear. Thus, the aim of this study was to elucidate the role of the RAS in fluoride-induced hypertension. Markers of the circulating and local RASs related to pathological changes to the kidneys, myocardium, and aorta were measured. Fluoride reduced serum levels of renin, angiotensin II (Ang II), and angiotensin (1-7) [Ang (1-7)], and dysregulated plasma levels of aldosterone and potassium levels. Excess fluoride can damage the kidneys, myocardium, and aorta, overactivate the renal angiotensin converting enzyme (ACE)-Ang II-angiotensin type 1 receptor axis, and inhibit activation of the ACE2-Ang (1-7)-Mas axis, leading to dysregulation of alpha epithelial sodium channels and significantly increased expression of Ang II in the myocardium and aorta. Hence, excess fluoride can cause low-renin hypertension via an imbalance between the circulatory and local RASs.
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Affiliation(s)
- Chenpeng Zhu
- Institute for Endemic Fluorosis Control, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health (23618504), Harbin, Heilongjiang, 150081, China
| | - Weikuan Gu
- Department of Orthopedic Surgery and BME-Campbell Clinic, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Dianjun Sun
- Institute for Endemic Fluorosis Control, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health (23618504), Harbin, Heilongjiang, 150081, China.
| | - Wei Wei
- Institute for Endemic Fluorosis Control, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health (23618504), Harbin, Heilongjiang, 150081, China.
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3
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Ye S, Wu P, Gao Z, Wang M, Zhou L, Qi Z. Inhibitory effect of S-nitroso-N-acetylpenicillamine on the basolateral 10-pS Cl- channel in thick ascending limb. PLoS One 2023; 18:e0284707. [PMID: 37083928 PMCID: PMC10121052 DOI: 10.1371/journal.pone.0284707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 04/05/2023] [Indexed: 04/22/2023] Open
Abstract
We have previously reported that L-arginine, a nitric oxide synthase substrate, inhibits the basolateral 10-pS Cl- channel through the cGMP/PKG signaling pathway in the thick ascending limb (TAL). As a NO releasing agent, the effect of S-nitroso-N-acetyl-penicillamine (SNAP) on the channel activity was examined in thick ascending limb of C57BL/6 mice in the present study. SNAP inhibited the basolateral 10-pS Cl- channel in a dose-dependent manner with an IC50 value of 6.6 μM. The inhibitory effect of SNAP was abolished not only by NO scavenger (carboxy-PTIO) but also by blockers of soluble guanylate cyclase (ODQ or LY-83583), indicating that the cGMP-dependent signaling pathway is involved. Moreover, the inhibitory effect of SNAP on the channel was strongly attenuated by a protein kinase G (PKG)-specific inhibitor, KT-5823, but not by the PDE2 inhibitor, BAY-60-7550. We concluded that SNAP inhibited the basolateral 10-pS Cl- channels in the TAL through a cGMP/PKG signaling pathway. As the 10-pS Cl- channel is important for regulation of NaCl absorption along the nephron, these data suggest that SNAP might be served as a regulator to prevent high-salt absorption related diseases, such as hypertension.
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Affiliation(s)
- Shiwei Ye
- Department of Basic Medical Sciences, School of Medicine, Xiamen University, Xiamen, China
| | - Peng Wu
- Department of Basic Medical Sciences, School of Medicine, Xiamen University, Xiamen, China
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Zhongxiuzi Gao
- Department of Basic Medical Sciences, School of Medicine, Xiamen University, Xiamen, China
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Mingyan Wang
- Department of Basic Medical Sciences, School of Medicine, Xiamen University, Xiamen, China
| | - Li Zhou
- Department of Basic Medical Sciences, School of Medicine, Xiamen University, Xiamen, China
| | - Zhi Qi
- Department of Basic Medical Sciences, School of Medicine, Xiamen University, Xiamen, China
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4
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Staruschenko A, Ma R, Palygin O, Dryer SE. Ion channels and channelopathies in glomeruli. Physiol Rev 2023; 103:787-854. [PMID: 36007181 PMCID: PMC9662803 DOI: 10.1152/physrev.00013.2022] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 08/15/2022] [Accepted: 08/21/2022] [Indexed: 11/22/2022] Open
Abstract
An essential step in renal function entails the formation of an ultrafiltrate that is delivered to the renal tubules for subsequent processing. This process, known as glomerular filtration, is controlled by intrinsic regulatory systems and by paracrine, neuronal, and endocrine signals that converge onto glomerular cells. In addition, the characteristics of glomerular fluid flow, such as the glomerular filtration rate and the glomerular filtration fraction, play an important role in determining blood flow to the rest of the kidney. Consequently, disease processes that initially affect glomeruli are the most likely to lead to end-stage kidney failure. The cells that comprise the glomerular filter, especially podocytes and mesangial cells, express many different types of ion channels that regulate intrinsic aspects of cell function and cellular responses to the local environment, such as changes in glomerular capillary pressure. Dysregulation of glomerular ion channels, such as changes in TRPC6, can lead to devastating glomerular diseases, and a number of channels, including TRPC6, TRPC5, and various ionotropic receptors, are promising targets for drug development. This review discusses glomerular structure and glomerular disease processes. It also describes the types of plasma membrane ion channels that have been identified in glomerular cells, the physiological and pathophysiological contexts in which they operate, and the pathways by which they are regulated and dysregulated. The contributions of these channels to glomerular disease processes, such as focal segmental glomerulosclerosis (FSGS) and diabetic nephropathy, as well as the development of drugs that target these channels are also discussed.
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Affiliation(s)
- Alexander Staruschenko
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, Florida
- Hypertension and Kidney Research Center, University of South Florida, Tampa, Florida
- James A. Haley Veterans Hospital, Tampa, Florida
| | - Rong Ma
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Oleg Palygin
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Stuart E Dryer
- Department of Biology and Biochemistry, University of Houston, Houston, Texas
- Department of Biomedical Sciences, Tilman J. Fertitta Family College of Medicine, University of Houston, Houston, Texas
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5
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Crorkin P, Hao S, Ferreri NR. Responses to Ang II (Angiotensin II), Salt Intake, and Lipopolysaccharide Reveal the Diverse Actions of TNF-α (Tumor Necrosis Factor-α) on Blood Pressure and Renal Function. Hypertension 2022; 79:2656-2670. [PMID: 36129177 PMCID: PMC9649876 DOI: 10.1161/hypertensionaha.122.19464] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
TNF-α (tumor necrosis factor-alpha) is the best known as a proinflammatory cytokine; yet, this cytokine also has important immunomodulatory and regulatory functions. As the effects of TNF-α on immune system function were being revealed, the spectrum of its activities appeared in conflict with each other before investigators defined the settings and mechanisms by which TNF-α contributed to both host defense and chronic inflammation. These effects reflect self-protective mechanisms that may become harmful when dysregulated. The paradigm of physiological and pathophysiological effects of TNF-α has since been uncovered in the lung, colon, and kidney where its role has been identified in pulmonary edema, electrolyte reabsorption, and blood pressure regulation, respectively. Recent studies on the prohypertensive and inflammatory effects of TNF-α in the cardiovascular system juxtaposed to those related to NaCl and blood pressure homeostasis, the response of the kidney to lipopolysaccharide, and protection against bacterial infections are helping define the mechanisms by which TNF-α modulates distinct functions within the kidney. This review discusses how production of TNF-α by renal epithelial cells may contribute to regulatory mechanisms that not only govern electrolyte excretion and blood pressure homeostasis but also maintain the appropriate local hypersalinity environment needed for optimizing the innate immune response to bacterial infections in the kidney. It is possible that the wide range of effects mediated by TNF-α may be related to severity of disease, amount of inflammation and TNF-α levels, and the specific cell types that produce this cytokine, areas that remain to be investigated further.
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Affiliation(s)
- Patrick Crorkin
- Department of Pharmacology, New York Medical College, Valhalla, NY
| | - Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla, NY
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6
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Xie Y, Qi H, Peng W, Li B, Wen F, Zhang F, Zhang L. Higher Potassium Intake and Lower Sodium Intake May Help in Reducing CVD Risk by Lowering Salt Sensitivity of Blood Pressure in the Han Chinese Population. Nutrients 2022; 14:nu14204436. [PMID: 36297119 PMCID: PMC9607620 DOI: 10.3390/nu14204436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 03/10/2023] Open
Abstract
Sodium (Na) reduction with a parallel supplemental potassium (K) intake can prevent cardiovascular diseases (CVDs). The relationship of the urinary Na/K ratio and salt sensitivity of blood pressure (SSBP) with CVDs is not clearly explained. We assumed that the SSBP mediates the relationship between the Na/K ratio and CVDs. In total, 2055 subjects who had 24 h urine collected and SSBP determined were included in this study. CVD risk was estimated using the China-PAR equation. MediationMultivariate logistic regression was used to explore the associations between the Na/K ratio or SSBP with CVD risk. Mediation analysis using a logistic regression model was performed. Both the urinary Na/K ratio and SSBP were related to the estimated CVD risk (p < 0.05). The mediation analysis found that SSBP mediated approximately 12% of the association between Na/K ratio and CVD risk. Our findings indicate that higher K intake and lower Na intake may help in preventing CVD risk by reducing SSBP risk in individuals with normotension or stage-one hypertension.
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Affiliation(s)
- Yunyi Xie
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, Beijing 100069, China
- Beijing Municipal Key Laboratory of Clinical Epidemiology, Capital Medical University, Beijing 100069, China
| | - Han Qi
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, Beijing 100069, China
- Beijing Municipal Key Laboratory of Clinical Epidemiology, Capital Medical University, Beijing 100069, China
| | - Wenjuan Peng
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, Beijing 100069, China
- Beijing Municipal Key Laboratory of Clinical Epidemiology, Capital Medical University, Beijing 100069, China
| | - Bingxiao Li
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, Beijing 100069, China
- Beijing Municipal Key Laboratory of Clinical Epidemiology, Capital Medical University, Beijing 100069, China
| | - Fuyuan Wen
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, Beijing 100069, China
- Beijing Municipal Key Laboratory of Clinical Epidemiology, Capital Medical University, Beijing 100069, China
| | - Fengxu Zhang
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, Beijing 100069, China
- Beijing Municipal Key Laboratory of Clinical Epidemiology, Capital Medical University, Beijing 100069, China
| | - Ling Zhang
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, Beijing 100069, China
- Beijing Municipal Key Laboratory of Clinical Epidemiology, Capital Medical University, Beijing 100069, China
- Correspondence: ; Tel.: +86-10-83911777
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7
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Osei-Owusu P, Collyer E, Dahlen SA, Echols Adams RE, Tom VJ. Maladaptation of Renal Hemodynamics Contributes to Kidney Dysfunction Resulting from Thoracic Spinal Cord Injury in Mice. Am J Physiol Renal Physiol 2022; 323:F120-F140. [PMID: 35658716 PMCID: PMC9306783 DOI: 10.1152/ajprenal.00072.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Renal dysfunction is a hallmark of spinal cord injury (SCI). Several SCI sequalae are implicated, however, the exact pathogenic mechanism of renal dysfunction is unclear. Herein, we found that T3 (T3Tx) or T10 (T10Tx) complete thoracic spinal cord transection induced hypotension, bradycardia, and hypothermia immediately after injury. T3Tx-induced hypotension but not bradycardia or hypothermia slowly recovered to levels in T10Tx SCI and uninjured mice ~16 h after injury as determined by continuous radiotelemetry monitoring. Both types of thoracic SCI led to a marked decrease in albuminuria and proteinuria in all phases of SCI, while the kidney injury marker, NGAL, rapidly increased in the acute phase, remaining elevated in the chronic phase of T3Tx SCI. Renal interstitial and vascular elastin fragmentation after SCI were worsened during chronic T3Tx SCI. In the chronic phase, renal vascular resistance response to a step increase in renal perfusion pressure or a bolus injection of Ang II or NE was almost completely abolished after T3Tx SCI. Bulk RNAseq analysis showed enrichment of genes involved in extracellular matrix (ECM) remodeling and chemokine signaling in the kidney from T3Tx SCI mice. Serum levels of interleukin 6 was elevated in the acute but not chronic phase of T3Tx and T10Tx SCI, while serum amyloid A1 level was elevated in both acute and chronic phases. We conclude that tissue fibrosis and hemodynamic impairment are involved in renal dysfunction resulting from thoracic SCI; these pathological alterations, exacerbated by high thoracic-level injury, is mediated at least partly by renal microvascular ECM remodeling.
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Affiliation(s)
- Patrick Osei-Owusu
- Physiology & Biophysics, Case Western Reserve University, Cleveland, OH, United States
| | - Eileen Collyer
- Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
| | - Shelby A Dahlen
- Physiology & Biophysics, Case Western Reserve University, Cleveland, OH, United States
| | - Raisa E Echols Adams
- Physiology & Biophysics, Case Western Reserve University, Cleveland, OH, United States
| | - Veronica J Tom
- Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
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8
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Komatsu Y, Aoyama K, Yoneda M, Ito S, Sano Y, Kawai Y, Cui X, Yamada Y, Furukawa N, Ikeda K, Nagata K. Surgical ablation of whitened interscapular brown fat ameliorates cardiac pathology in salt-loaded metabolic syndrome rats. Ann N Y Acad Sci 2020; 1492:11-26. [PMID: 33340110 DOI: 10.1111/nyas.14546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/27/2020] [Accepted: 11/12/2020] [Indexed: 11/30/2022]
Abstract
Brown adipose tissue (BAT) is an endocrine organ that contributes to thermogenesis and energy consumption. We investigated the effects of salt loading and surgical removal of whitened interscapular BAT (iBAT) on cardiac and adipose tissue pathology in DahlS.Z-Leprfa /Leprfa (DS/obese) rats, an animal model of metabolic syndrome (MetS). DS/obese rats were subjected to surgical removal of iBAT or sham surgery at 8 weeks of age and were provided with drinking water containing or not containing 0.3% NaCl for 4 weeks beginning at 9 weeks of age. Removal of iBAT suppressed the salt-induced exacerbation of left ventricular inflammation, fibrosis, and diastolic dysfunction, but not that of hypertension development, in DS/obese rats. Salt loading attenuated adipocyte hypertrophy but enhanced inflammation in both visceral white adipose tissue (WAT) and iBAT. Although iBAT removal did not affect visceral WAT pathology in salt-loaded DS/obese rats, it attenuated the elevation of circulating interleukin-6 levels in these animals. Downregulation of uncoupling protein-1 expression in iBAT of DS/obese rats was not affected by salt loading. Our results suggest that the conversion of iBAT to WAT-like tissue contributes to a salt-induced elevation of circulating proinflammatory cytokine levels that leads to exacerbation of cardiac pathology in this model of MetS.
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Affiliation(s)
- Yuki Komatsu
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kiyoshi Aoyama
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Mamoru Yoneda
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shogo Ito
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yusuke Sano
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yumeno Kawai
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Xixi Cui
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuichiro Yamada
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Nozomi Furukawa
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Katsuhide Ikeda
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kohzo Nagata
- Pathophysiology Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
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9
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Wang J, Miecznikowski JC. High precision implementation of Steck's recursion method for use in goodness-of-fit tests. J Appl Stat 2020; 49:1348-1363. [DOI: 10.1080/02664763.2020.1861224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Jiefei Wang
- Department of Biostatistics, SUNY University at Buffalo, Buffalo, NY, USA
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10
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Garneau AP, Slimani S, Fiola MJ, Tremblay LE, Isenring P. Multiple Facets and Roles of Na+-K+-Cl−Cotransport: Mechanisms and Therapeutic Implications. Physiology (Bethesda) 2020; 35:415-429. [DOI: 10.1152/physiol.00012.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The Na+-K+-Cl−cotransporters play key physiological and pathophysiological roles by regulating the membrane potential of many cell types and the movement of fluid across a variety of epithelial or endothelial structures. As such, they should soon become invaluable targets for the treatment of various disorders including pain, epilepsy, brain edema, and hypertension. This review highlights the nature of these roles, the mechanisms at play, and the unresolved issues in the field.
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Affiliation(s)
- A. P. Garneau
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Canada; and
- Cardiometabolic Axis, School of Kinesiology and Physical Activity Sciences, University of Montréal, Montréal, Canada
| | - S. Slimani
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Canada; and
| | - M. J. Fiola
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Canada; and
| | - L. E. Tremblay
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Canada; and
| | - P. Isenring
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Canada; and
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11
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Marcoux AA, Tremblay LE, Slimani S, Fiola MJ, Mac-Way F, Garneau AP, Isenring P. Molecular characteristics and physiological roles of Na + -K + -Cl - cotransporter 2. J Cell Physiol 2020; 236:1712-1729. [PMID: 32776569 PMCID: PMC7818487 DOI: 10.1002/jcp.29997] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 06/28/2020] [Accepted: 07/24/2020] [Indexed: 12/23/2022]
Abstract
Na+–K+–Cl− cotransporter 2 (NKCC2; SLC12A1) is an integral membrane protein that comes as three splice variants and mediates the cotranslocation of Na+, K+, and Cl− ions through the apical membrane of the thick ascending loop of Henle (TALH). In doing so, and through the involvement of other ion transport systems, it allows this nephron segment to reclaim a large fraction of the ultrafiltered Na+, Cl−, Ca2+, Mg2+, and HCO3− loads. The functional relevance of NKCC2 in human is illustrated by the many abnormalities that result from the inactivation of this transport system through the use of loop diuretics or in the setting of inherited disorders. The following presentation aims at discussing the physiological roles and molecular characteristics of Na+–K+–Cl− cotransport in the TALH and those of the individual NKCC2 splice variants more specifically. Many of the historical and recent data that have emerged from the experiments conducted will be outlined and their larger meaning will also be placed into perspective with the aid of various hypotheses.
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Affiliation(s)
- Andree-Anne Marcoux
- Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada
| | - Laurence E Tremblay
- Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada
| | - Samira Slimani
- Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada
| | - Marie-Jeanne Fiola
- Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada
| | - Fabrice Mac-Way
- Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada
| | - Alexandre P Garneau
- Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada.,Cardiometabolic Axis, School of Kinesiology and Physical Activity Sciences, University of Montréal, Montréal, Quebec, Canada
| | - Paul Isenring
- Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada
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12
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Ramachandran CD, Gholami K, Lam SK, Hoe SZ. A preliminary study of the effect of a high-salt diet on transcriptome dynamics in rat hypothalamic forebrain and brainstem cardiovascular control centers. PeerJ 2020; 8:e8528. [PMID: 32175184 PMCID: PMC7059759 DOI: 10.7717/peerj.8528] [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: 07/09/2019] [Accepted: 01/07/2020] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND High dietary salt intake is strongly correlated with cardiovascular (CV) diseases and it is regarded as a major risk factor associated with the pathogenesis of hypertension. The CV control centres in the brainstem (the nucleus tractus solitarii (NTS) and the rostral ventrolateral medulla (RVLM)) and hypothalamic forebrain (the subfornical organ, SFO; the supraoptic nucleus, SON and the paraventricular nucleus, PVN) have critical roles in regulating CV autonomic motor outflows, and thus maintaining blood pressure (BP). Growing evidence has implicated autonomic regulatory networks in salt-sensitive HPN (SSH), but the genetic basis remains to be delineated. We hypothesized that the development and/ or maintenance of SSH is reliant on the change in the expression of genes in brain regions controlling the CV system. METHODOLOGY We used RNA-Sequencing (RNA-Seq) to describe the differential expression of genes in SFO, SON, PVN, NTS and RVLM of rats being chronically fed with high-salt (HS) diet. Subsequently, a selection of putatively regulated genes was validated with quantitative reverse transcription polymerase chain reaction (qRT-PCR) in both Spontaneously Hypertensive rats (SHRs) and Wistar Kyoto (WKY) rats. RESULTS The findings enabled us to identify number of differentially expressed genes in SFO, SON, PVN, NTS and RVLM; that are either up-regulated in both strains of rats (SON- Caprin2, Sctr), down-regulated in both strains of rats (PVN- Orc, Gkap1), up-regulated only in SHRs (SFO- Apopt1, Lin52, AVP, OXT; SON- AVP, OXT; PVN- Caprin2, Sclt; RVLM- A4galt, Slc29a4, Cmc1) or down-regulated only in SHRs (SON- Ndufaf2, Kcnv1; PVN- Pi4k2a; NTS- Snrpd2l, Ankrd29, St6galnac6, Rnf157, Iglon5, Csrnp3, Rprd1a; RVLM- Ttr, Faim). CONCLUSIONS These findings demonstrated the adverse effects of HS diet on BP, which may be mediated via modulating the signaling systems in CV centers in the hypothalamic forebrain and brainstem.
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Affiliation(s)
- Chitra Devi Ramachandran
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Wilayah Perseketuan, Malaysia
| | - Khadijeh Gholami
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Wilayah Perseketuan, Malaysia
- Human Biology Division, School of Medicine, International Medical University, Kuala Lumpur, Wilayah Perseketuan, Malaysia
| | - Sau Kuen Lam
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Wilayah Perseketuan, Malaysia
- Department of Pre-Clinical Sciences, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, Sungai Long, Selangor, Malaysia
| | - See Ziau Hoe
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Wilayah Perseketuan, Malaysia
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Yoshimoto M, Onishi Y, Mineyama N, Ikegame S, Shirai M, Osborn JW, Miki K. Renal and Lumbar Sympathetic Nerve Activity During Development of Hypertension in Dahl Salt-Sensitive Rats. Hypertension 2019; 74:888-895. [DOI: 10.1161/hypertensionaha.119.12866] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To study the contribution of sympathetic nerve activity (SNA) to the development of hypertension, experiments were designed to continuously and simultaneously measure renal (RSNA) and lumbar SNA (LSNA) during the development of hypertension induced by 8% salt loading in Dahl salt-sensitive (DS) rats. Male DS and salt-resistant rats were instrumented with bipolar electrodes to record RSNA and LSNA and a telemeter to record arterial pressure (AP). AP increased during the first 3 days after the onset of salt loading by ≈10 mm Hg in both DS and Dahl salt-resistant rats. AP continued to increase progressively from day 4 to day 14 of salt loading by 33±1 mm Hg in DS rats, while it remained the same in Dahl salt-resistant rats. RSNA and LSNA increased in the initial few days by 6% to 8%, and decreased gradually thereafter, suggesting that increases in neither RSNA nor LSNA are directly linked with the progressive increase in AP induced by salt loading in DS rats. After the cessation of salt loading, AP pressure returned to the presalt loading level in both DS and Dahl salt-resistant rats. RSNA increased significantly by 32±3% after the cessation of salt loading, while LSNA remained the same in DS rats, suggesting that salt-sensitive mechanisms respond to a loss of sodium, not a gain, and selectively activate RSNA in DS rats. In summary, RSNA and LSNA are not likely to be a primary trigger to initiate the progressive increase in AP induced by 8% salt loading in DS rats.
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Affiliation(s)
- Misa Yoshimoto
- From the Department of Environmental Health, Life Science and Human Technology, Nara Women’s University, Kita-Uoya Nishimachi (M.Y., Y.O., N.M., S.I., K.M.)
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan (M.Y., M.S.)
| | - Yuko Onishi
- From the Department of Environmental Health, Life Science and Human Technology, Nara Women’s University, Kita-Uoya Nishimachi (M.Y., Y.O., N.M., S.I., K.M.)
| | - Naoko Mineyama
- From the Department of Environmental Health, Life Science and Human Technology, Nara Women’s University, Kita-Uoya Nishimachi (M.Y., Y.O., N.M., S.I., K.M.)
| | - Shizuka Ikegame
- From the Department of Environmental Health, Life Science and Human Technology, Nara Women’s University, Kita-Uoya Nishimachi (M.Y., Y.O., N.M., S.I., K.M.)
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan (M.Y., M.S.)
| | - John W. Osborn
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis (J.W.O.)
| | - Kenju Miki
- From the Department of Environmental Health, Life Science and Human Technology, Nara Women’s University, Kita-Uoya Nishimachi (M.Y., Y.O., N.M., S.I., K.M.)
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14
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Klimanova EA, Sidorenko SV, Smolyaninova LV, Kapilevich LV, Gusakova SV, Lopina OD, Orlov SN. Ubiquitous and cell type-specific transcriptomic changes triggered by dissipation of monovalent cation gradients in rodent cells: Physiological and pathophysiological implications. CURRENT TOPICS IN MEMBRANES 2019; 83:107-149. [PMID: 31196602 DOI: 10.1016/bs.ctm.2019.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Elevation of [Na+]i/[K+]i-ratio is considered as one of the major signals triggering transcriptomic changes in various cells types. In this study, we identified ubiquitous and cell type-specific [Formula: see text] -sensitive genes by comparative analysis of transcriptomic changes in ouabain-treated rat aorta smooth muscle cells and rat aorta endothelial cells (RASMC and RAEC, respectively), rat cerebellar granule cells (RCGC), and mouse C2C12 myoblasts. Exposure of the cells to ouabain increased intracellular Na+ content by ~14, 8, 7, and 6-fold and resulted in appearance of 7577, 2698, 2120, and 1146 differentially expressed transcripts in RAEC, RASMC, C2C12, and RCGC, respectively. Eighty-three genes were found as the intersection of the four sets of identified transcripts corresponding to each cell type and are classified as ubiquitous. Among the 10 top upregulated ubiquitous transcripts are the following: Dusp6, Plk3, Trib1, Ccl7, Mafk, Atf3, Ptgs2, Cxcl1, Spry4, and Coq10b. Unique transcripts whose expression is cell-specific include 4897, 1523, 789, and 494 transcripts for RAEC, RASMC, C2C12, and RCGC, respectively. The role of gene expression and signal pathways induced by dissipation of transmembrane gradient of monovalent cations in the development of various diseases is discussed with special attention to cardiovascular and pulmonary illnesses.
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Affiliation(s)
- Elizaveta A Klimanova
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia.
| | - Svetlana V Sidorenko
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia
| | - Larisa V Smolyaninova
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia
| | | | | | - Olga D Lopina
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Sergei N Orlov
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia; Siberian State Medical University, Tomsk, Russia
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15
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Paczula A, Wiecek A, Piecha G. Cardiotonic Steroids-A Possible Link Between High-Salt Diet and Organ Damage. Int J Mol Sci 2019; 20:ijms20030590. [PMID: 30704040 PMCID: PMC6386955 DOI: 10.3390/ijms20030590] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 01/24/2019] [Accepted: 01/28/2019] [Indexed: 02/07/2023] Open
Abstract
High dietary salt intake has been listed among the top ten risk factors for disability-adjusted life years. We discuss the role of endogenous cardiotonic steroids in mediating the dietary salt-induced hypertension and organ damage.
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Affiliation(s)
- Aneta Paczula
- Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia, Francuska 20-24, 40-027 Katowice, Poland.
| | - Andrzej Wiecek
- Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia, Francuska 20-24, 40-027 Katowice, Poland.
| | - Grzegorz Piecha
- Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia, Francuska 20-24, 40-027 Katowice, Poland.
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16
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Blaženović I, Oh YT, Li F, Ji J, Nguyen AK, Wancewicz B, Bender JM, Fiehn O, Youn JH. Effects of Gut Bacteria Depletion and High-Na + and Low-K + Intake on Circulating Levels of Biogenic Amines. Mol Nutr Food Res 2018; 63:e1801184. [PMID: 30513547 DOI: 10.1002/mnfr.201801184] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 11/13/2018] [Indexed: 12/18/2022]
Abstract
SCOPE High-sodium and low-potassium (HNaLK) content in Western diets increases the risk of hypertension and cardiovascular disease (CVD). It is investigated if the dietary minerals interact with gut bacteria to modulate circulating levels of biogenic amines, which are implicated in various pathologies, including hypertension and CVD. METHODS AND RESULTS Using a metabolomic approach to target biogenic amines, the effects of gut bacteria depletion and HNaLK intake on circulating levels of biogenic amines in rats are examined. Forty-five metabolites whose plasma levels are significantly altered by gut bacteria depletion (p < 0.05) are found, indicating their regulation by gut bacteria. Many of them are not previously linked to gut bacteria; therefore, these data provide novel insights into physiological or pathological roles of gut bacteria. A number of plasma metabolites that are altered both by gut bacteria and HNaLK intake are also found, suggesting possible interactions of the diet and gut bacteria in the modulation of these metabolites. The diet effects are observed with significant changes in the gut bacterial taxa Porphyromonadaceae and Prevotellaceae (p < 0.05). CONCLUSION The dietary minerals may regulate abundances of certain gut bacteria to alter circulating levels of biogenic amines, which may be linked to host physiology or pathology.
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Affiliation(s)
- Ivana Blaženović
- West Coast Metabolomics Center, University of California Davis Genome Center, Davis, CA 95616, USA
| | - Young Taek Oh
- Department of Physiology and Neuroscience, Keck School of Medicine of USC, Los Angeles, CA 90089, USA
| | - Fan Li
- Single Cell, Sequencing, and CyTOF Core Lab, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA
| | - Jian Ji
- West Coast Metabolomics Center, University of California Davis Genome Center, Davis, CA 95616, USA.,School of Food Science, State Key Laboratory of Food Science and Technology, National Engineering Research Center for Functional Foods, School of Food Science Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi, Jiangsu, China
| | - Ahn-Khoi Nguyen
- Department of Exercise Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Benjamin Wancewicz
- West Coast Metabolomics Center, University of California Davis Genome Center, Davis, CA 95616, USA
| | - Jeffrey M Bender
- USC Keck School of Medicine and Children's Hospital Los Angeles, Los Angeles, CA 90027, USA
| | - Oliver Fiehn
- West Coast Metabolomics Center, University of California Davis Genome Center, Davis, CA 95616, USA.,Department of Biochemistry, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Jang H Youn
- Department of Physiology and Neuroscience, Keck School of Medicine of USC, Los Angeles, CA 90089, USA
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17
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Sun CQ. Aqueous charge injection: solvation bonding dynamics, molecular nonbond interactions, and extraordinary solute capabilities. INT REV PHYS CHEM 2018. [DOI: 10.1080/0144235x.2018.1544446] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Chang Q. Sun
- EBEAM, Yangtze Normal University, Chongqing, People's Republic of China
- NOVITAS, EEE, Nanyang Technological University, Singapore, Singapore
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18
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Orlov SN, Shiyan A, Boudreault F, Ponomarchuk O, Grygorczyk R. Search for Upstream Cell Volume Sensors: The Role of Plasma Membrane and Cytoplasmic Hydrogel. CURRENT TOPICS IN MEMBRANES 2018; 81:53-82. [PMID: 30243440 DOI: 10.1016/bs.ctm.2018.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
The plasma membrane plays a prominent role in the regulation of cell volume by mediating selective transport of extra- and intracellular osmolytes. Recent studies show that upstream sensors of cell volume changes are mainly located within the cytoplasm that displays properties of a hydrogel and not in the plasma membrane. Cell volume changes occurring in anisosmotic medium as well as in isosmotic environment affect properties of cytoplasmic hydrogel that, in turn, trigger rapid regulatory volume increase and decrease (RVI and RVD). The downstream signaling pathways include reorganization of 2D cytoskeleton and altered composition of polyphosphoinositides located on the inner surface of the plasma membrane. In addition to its action on physico-chemical properties of cytoplasmic hydrogel, cell volume changes in anisosmotic conditions affect the ionic strength of the cytoplasm and the [Na+]i/[K+]i ratio. Elevated intracellular ionic strength evoked by long term exposure of cells to hypertonic environment resulted in the activation of TonEBP and augmented expression of genes controlling intracellular organic osmolyte levels. The role of Na+i/K+i -sensitive, Ca2+i -mediated and Ca2+i-independent mechanisms of excitation-transcription coupling in cell volume-adjustment remains unknown.
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Affiliation(s)
- Sergei N Orlov
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia; Siberian State Medical University, Tomsk, Russia; National Research Tomsk State University, Tomsk, Russia
| | - Aleksandra Shiyan
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Francis Boudreault
- Centre de recherche, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Olga Ponomarchuk
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia; Centre de recherche, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Ryszard Grygorczyk
- Centre de recherche, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada; Department of Medicine, Faculty of Medicine, University of Montreal, Montreal, QC, Canada
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19
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Eisele N, Klossner R, Escher G, Rudloff S, Larionov A, Theilig F, Mohaupt MG, Mistry HD, Gennari‐Moser C. Physiological and Molecular Responses to Altered Sodium Intake in Rat Pregnancy. J Am Heart Assoc 2018; 7:e008363. [PMID: 30371243 PMCID: PMC6201473 DOI: 10.1161/jaha.117.008363] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 06/07/2018] [Indexed: 11/21/2022]
Abstract
Background In pregnancy, a high plasma volume maintains uteroplacental perfusion and prevents placental ischemia, a condition linked to elevated maternal blood pressure ( BP ). Reducing BP by increasing Na+ intake via plasma volume expansion appears contra-intuitive. We hypothesize that an appropriate Na+ intake in pregnancy reduces maternal BP and adapts the renin-angiotensin system in a pregnancy-specific manner. Methods and Results BP was measured by implanted telemetry in Sprague-Dawley rats before and throughout pregnancy. Pregnant and nonpregnant animals received either a normal-salt (0.4%; NS ), high-salt (8%; HS ), or low-salt (0.01%; LS ) diet, or HS (days 1-14) followed by LS (days 14-20) diet ( HS / LS ). Before delivery (day 20), animals were euthanized and organs collected. Food, water, and Na+ intake were monitored in metabolic cages, and urinary creatinine and Na+ were analyzed. Na+ intake and retention increased in pregnancy ( NS , LS ), leading to a positive Na+ balance ( NS , LS ). BP was stable during LS , but reduced in HS conditions in pregnancy. The renin-angiotensin system was adapted as expected. Activating cleavage of α- and γ-subunits of the renal epithelial Na+ channel and expression of-full length medullary β-subunits, accentuated further in all LS conditions, were upregulated in pregnancy. Conclusions Pregnancy led to Na+ retention adapted to dietary changes. HS exposure paradoxically reduced BP . Na+ uptake while only modestly linked to the renin-angiotensin system is enhanced in the presence of posttranslational renal epithelial Na+ channel modifications. This suggests (1) storage of Na+ in pregnancy upon HS exposure, bridging periods of LS availability; and (2) that potentially non-renin-angiotensin-related mechanisms participate in EN aC activation and consecutive Na+ retention.
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Affiliation(s)
- Nicole Eisele
- Department of Nephrology and HypertensionUniversity of BernSwitzerland
- Department of BioMedical ResearchUniversity of BernSwitzerland
| | - Rahel Klossner
- Department of BioMedical ResearchUniversity of BernSwitzerland
- Teaching Hospital Internal Medicine LindenhofgruppeBerneSwitzerland
| | - Geneviève Escher
- Department of Nephrology and HypertensionUniversity of BernSwitzerland
- Department of BioMedical ResearchUniversity of BernSwitzerland
| | - Stefan Rudloff
- Department of Nephrology and HypertensionUniversity of BernSwitzerland
- Department of BioMedical ResearchUniversity of BernSwitzerland
| | - Alexey Larionov
- Division of Internal MedicineUniversity of FribourgSwitzerland
| | | | - Markus G. Mohaupt
- Department of BioMedical ResearchUniversity of BernSwitzerland
- Teaching Hospital Internal Medicine LindenhofgruppeBerneSwitzerland
| | - Hiten D. Mistry
- Department of BioMedical ResearchUniversity of BernSwitzerland
- Division of Child Health, Obstetrics and GynaecologySchool of MedicineCity Hospital NottinghamNottinghamUnited Kingdom
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20
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Ni C, Sun C, Zhou Z, Huang Y, Liu X. Surface tension mediation by Na-based ionic polarization and acidic fragmentation: Inference of hypertension. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.02.113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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21
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Zhang B, Nakata M, Lu M, Nakae J, Okada T, Ogawa W, Yada T. Protective role of AgRP neuron's PDK1 against salt-induced hypertension. Biochem Biophys Res Commun 2018; 500:910-916. [PMID: 29705701 DOI: 10.1016/j.bbrc.2018.04.192] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Accepted: 04/24/2018] [Indexed: 10/17/2022]
Abstract
In the hypothalamic arcuate nucleus (ARC), orexigenic agouti-related peptide (AgRP) neurons regulate feeding behavior and energy homeostasis. The 3-phosphoinositide-dependent protein kinase-1 (PDK1) in AgRP neurons serves as a major signaling molecule for leptin and insulin, the hormones regulating feeding behavior, energy homeostasis and circulation. However, it is unclear whether PDK1 in AGRP neurons is also involved in regulation of blood pressure. This study explored it by generating and analyzing AgRP neuron-specific PDK1 knockout (Agrp-Pdk1flox/flox) mice and effect of high salt diet on blood pressure in KO and WT mice was analyzed. Under high salt diet feeding, systolic blood pressure (SBP) of Agrp-Pdk1flox/flox mice was significantly elevated compared to Agrp-Cre mice. When the high salt diet was switched to control low salt diet, SBP of Agrp-Pdk1flox/flox mice returned to the basal level observed in Agrp-Cre mice within 1 week. In Agrp-Pdk1flox/flox mice, urinary noradrenalin excretion and NUCB2 mRNA expression in hypothalamic paraventricular nucleus (PVN) were markedly upregulated. Moreover, silencing of NUCB2 in the PVN counteracted the rises in urinary noradrenalin excretions and SBP. These results demonstrate a novel role of PDK1 in AgRP neurons to counteract the high salt diet-induced hypertension by preventing hyperactivation of PVN nesfatin-1 neurons.
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Affiliation(s)
- Boyang Zhang
- Department of Physiology, Jichi Medical University, School of Medicine, Japan
| | - Masanori Nakata
- Department of Physiology, Jichi Medical University, School of Medicine, Japan; Department of Physiology, Wakayama Medical University School of Medicine, Japan.
| | - Ming Lu
- Department of Physiology, Jichi Medical University, School of Medicine, Japan
| | - Jun Nakae
- Frontier Medicine on Metabolic Syndrome, Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, Keio University School of Medicine, Japan
| | - Takashi Okada
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Japan
| | - Wataru Ogawa
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan
| | - Toshihiko Yada
- Department of Physiology, Jichi Medical University, School of Medicine, Japan; Center for Integrative Physiology, Division of Integrative Physiology, Kansai Electric Power Medical Research Institute, Japan.
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22
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Chronic Blockade of Brain Endothelin Receptor Type-A (ET A) Reduces Blood Pressure and Prevents Catecholaminergic Overactivity in the Right Olfactory Bulb of DOCA-Salt Hypertensive Rats. Int J Mol Sci 2018; 19:ijms19030660. [PMID: 29495426 PMCID: PMC5877521 DOI: 10.3390/ijms19030660] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/05/2018] [Accepted: 02/08/2018] [Indexed: 01/06/2023] Open
Abstract
Overactivity of the sympathetic nervous system and central endothelins (ETs) are involved in the development of hypertension. Besides the well-known brain structures involved in the regulation of blood pressure like the hypothalamus or locus coeruleus, evidence suggests that the olfactory bulb (OB) also modulates cardiovascular function. In the present study, we evaluated the interaction between the endothelinergic and catecholaminergic systems in the OB of deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Following brain ET receptor type A (ETA) blockade by BQ610 (selective antagonist), transcriptional, traductional, and post-traductional changes in tyrosine hydroxylase (TH) were assessed in the OB of normotensive and DOCA-salt hypertensive rats. Time course variations in systolic blood pressure and heart rate were also registered. Results showed that ETA blockade dose dependently reduced blood pressure in hypertensive rats, but it did not change heart rate. It also prevented the increase in TH activity and expression (mRNA and protein) in the right OB of hypertensive animals. However, ETA blockade did not affect hemodynamics or TH in normotensive animals. Present results support that brain ETA are not involved in blood pressure regulation in normal rats, but they significantly contribute to chronic blood pressure elevation in hypertensive animals. Changes in TH activity and expression were observed in the right but not in the left OB, supporting functional asymmetry, in line with previous studies regarding cardiovascular regulation. Present findings provide further evidence on the role of ETs in the regulation of catecholaminergic activity and the contribution of the right OB to DOCA-salt hypertension.
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23
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Jiang E, Chapp AD, Fan Y, Larson RA, Hahka T, Huber MJ, Yan J, Chen QH, Shan Z. Expression of Proinflammatory Cytokines Is Upregulated in the Hypothalamic Paraventricular Nucleus of Dahl Salt-Sensitive Hypertensive Rats. Front Physiol 2018. [PMID: 29520237 PMCID: PMC5826963 DOI: 10.3389/fphys.2018.00104] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Accumulating evidence indicates that inflammation is implicated in hypertension. However, the role of brain proinflammatory cytokines (PICs) in salt sensitive hypertension remains to be determined. Thus, the objective of this study was to test the hypothesis that high salt (HS) diet increases PICs expression in the paraventricular nucleus (PVN) and leads to PVN neuronal activation. Eight-week-old male Dahl salt sensitive (Dahl S) rats, and age and sex matched normal Sprague Dawley (SD) rats were divided into two groups and fed with either a HS (4% NaCl) or normal salt (NS, 0.4% NaCl) diet for 5 consecutive weeks. HS diet induced hypertension and significantly increased cerebrospinal fluid (CSF) sodium concentration ([Na+]) in Dahl S rats, but not in normal SD rats. In addition, HS diet intake triggered increases in mRNA levels and immunoreactivities of PVN PICs including TNF-α, IL-6, and IL-1β, as well as Fra1, a chronic marker of neuronal activation, in Dahl S rats, but not in SD rats. Next, we investigated whether this increase in the expression of PVN PICs and Fra1 was induced by increased CSF [Na+]. Adult male SD rats were intracerebroventricular (ICV) infused with 8 μl of either hypertonic salt (4 μmol NaCl), mannitol (8 μmol, as osmolarity control), or isotonic salt (0.9% NaCl as vehicle control). Three hours following the ICV infusion, rats were euthanized and their PVN PICs expression was measured. The results showed that central administration of hypertonic saline in SD rats significantly increased the expression of PICs including TNF-α, IL-6, and IL-1β, as well as neuronal activation marker Fra1, compared to isotonic NaCl controls and osmolarity controls. Finally, we tested whether the increase in PICs expression occurred in neurons. Incubation of hypothalamic neurons with 10 mM NaCl in a culture medium for 6 h elicited significant increases in TNF-α, IL-6, and Fra1 mRNA levels. These observations, coupled with the important role of PICs in modulating neuronal activity and stimulating vasopressin release, suggest that HS intake induces an inflammatory state in the PVN, which, may in turn, augments sympathetic nerve activity and vasopressin secretion, contributing to the development of salt sensitive hypertension.
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Affiliation(s)
- Enshe Jiang
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States.,Institute for Nursing and Health Research, Henan University, Kaifeng, China
| | - Andrew D Chapp
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| | - Yuanyuan Fan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States.,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Robert A Larson
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| | - Taija Hahka
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| | - Michael J Huber
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| | - Jianqun Yan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Qing-Hui Chen
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| | - Zhiying Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
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Na⁺ i,K⁺ i-Dependent and -Independent Signaling Triggered by Cardiotonic Steroids: Facts and Artifacts. Molecules 2017; 22:molecules22040635. [PMID: 28420099 PMCID: PMC6153942 DOI: 10.3390/molecules22040635] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 03/31/2017] [Accepted: 04/11/2017] [Indexed: 11/17/2022] Open
Abstract
Na⁺,K⁺-ATPase is the only known receptor of cardiotonic steroids (CTS) whose interaction with catalytic α-subunits leads to inhibition of this enzyme. As predicted, CTS affect numerous cellular functions related to the maintenance of the transmembrane gradient of monovalent cations, such as electrical membrane potential, cell volume, transepithelial movement of salt and osmotically-obliged water, symport of Na⁺ with inorganic phosphate, glucose, amino acids, nucleotides, etc. During the last two decades, it was shown that side-by-side with these canonical Na⁺i/K⁺i-dependent cellular responses, long-term exposure to CTS affects transcription, translation, tight junction, cell adhesion and exhibits tissue-specific impact on cell survival and death. It was also shown that CTS trigger diverse signaling cascades via conformational transitions of the Na⁺,K⁺-ATPase α-subunit that, in turn, results in the activation of membrane-associated non-receptor tyrosine kinase Src, phosphatidylinositol 3-kinase and the inositol 1,4,5-triphosphate receptor. These findings allowed researchers to propose that endogenous CTS might be considered as a novel class of steroid hormones. We focus our review on the analysis of the relative impact Na⁺i,K⁺i-mediated and -independent pathways in cellular responses evoked by CTS.
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25
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Affiliation(s)
- Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, China.,Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Pedro A Jose
- Division of Renal Disease & Hypertension, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China
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Marunaka Y, Marunaka R, Sun H, Yamamoto T, Kanamura N, Taruno A. Na + homeostasis by epithelial Na + channel (ENaC) and Na x channel (Na x): cooperation of ENaC and Na x. ANNALS OF TRANSLATIONAL MEDICINE 2016; 4:S11. [PMID: 27867979 DOI: 10.21037/atm.2016.10.42] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Yoshinori Marunaka
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan;; Department of Bio-Ionomics, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan;; Japan Institute for Food Education and Health, St. Agnes' University, Kyoto 602-8013, Japan
| | - Rie Marunaka
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan;; Department of Dental Medicine, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan
| | - Hongxin Sun
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan
| | - Toshiro Yamamoto
- Department of Dental Medicine, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan
| | - Narisato Kanamura
- Department of Dental Medicine, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan
| | - Akiyuki Taruno
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan
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Digne-Malcolm H, Frise MC, Dorrington KL. How Do Antihypertensive Drugs Work? Insights from Studies of the Renal Regulation of Arterial Blood Pressure. Front Physiol 2016; 7:320. [PMID: 27524972 PMCID: PMC4965470 DOI: 10.3389/fphys.2016.00320] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 07/13/2016] [Indexed: 11/13/2022] Open
Abstract
Though antihypertensive drugs have been in use for many decades, the mechanisms by which they act chronically to reduce blood pressure remain unclear. Over long periods, mean arterial blood pressure must match the perfusion pressure necessary for the kidney to achieve its role in eliminating the daily intake of salt and water. It follows that the kidney is the most likely target for the action of most effective antihypertensive agents used chronically in clinical practice today. Here we review the long-term renal actions of antihypertensive agents in human studies and find three different mechanisms of action for the drugs investigated. (i) Selective vasodilatation of the renal afferent arteriole (prazosin, indoramin, clonidine, moxonidine, α-methyldopa, some Ca(++)-channel blockers, angiotensin-receptor blockers, atenolol, metoprolol, bisoprolol, labetolol, hydrochlorothiazide, and furosemide). (ii) Inhibition of tubular solute reabsorption (propranolol, nadolol, oxprenolol, and indapamide). (iii) A combination of these first two mechanisms (amlodipine, nifedipine and ACE-inhibitors). These findings provide insights into the actions of antihypertensive drugs, and challenge misconceptions about the mechanisms underlying the therapeutic efficacy of many of the agents.
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Affiliation(s)
| | - Matthew C. Frise
- Department of Physiology, Anatomy and Genetics, University of OxfordOxford, UK
| | - Keith L. Dorrington
- Department of Physiology, Anatomy and Genetics, University of OxfordOxford, UK
- Nuffield Department of Anaesthetics, John Radcliffe HospitalOxford, UK
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Cao Y, Fang Y, Mu J, Liu X. High salt medium activates RhoA/ROCK and downregulates eNOS expression via the upregulation of ADMA. Mol Med Rep 2016; 14:606-12. [PMID: 27175806 DOI: 10.3892/mmr.2016.5241] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 04/18/2016] [Indexed: 11/05/2022] Open
Abstract
Endothelial dysfunction has an important role in the development and progression of salt-sensitive hypertension. Asymmetric dimethylarginine (ADMA), which is an endogenous inhibitor of nitric oxide synthase (NOS), has been demonstrated to be involved in the pathophysiological processes of endothelial dysfunction and salt‑sensitive hypertension. However, it is currently unclear how high salt intake may induce these processes. The present study investigated the effects of high salt medium on ADMA, endothelial NOS (eNOS) and the Ras homolog gene family, member A (RhoA)/Rho-associated protein kinase (ROCK) pathway in the EA.hy926 umbilical vein cell line. The results demonstrated that high salt medium significantly increased the concentration of ADMA, the expression of protein arginine methyltransferase 1 (PRMT‑1) and RhoA, and the activity of ROCK, and downregulated the expression of eNOS. Knockdown of PRMT-1 with small interfering RNA (siRNA) significantly abrogated the aforementioned effects. These results indicated that ADMA has a key role in high salt‑mediated activation of the RhoA/ROCK pathway and inhibition of eNOS biosynthesis. siRNA‑PRMT‑1 may be considered a novel remedy for the treatment of endothelial dysfunction.
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Affiliation(s)
- Yu Cao
- Department of Pediatrics, First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Yuan Fang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Jianjun Mu
- Department of Cardiovascular Medicine, First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Xiaohong Liu
- Department of Pediatrics, First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
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Orlov SN, Koltsova SV, Kapilevich LV, Gusakova SV, Dulin NO. NKCC1 and NKCC2: The pathogenetic role of cation-chloride cotransporters in hypertension. Genes Dis 2015; 2:186-196. [PMID: 26114157 PMCID: PMC4477834 DOI: 10.1016/j.gendis.2015.02.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 02/16/2015] [Indexed: 11/17/2022] Open
Abstract
This review summarizes the data on the functional significance of ubiquitous (NKCC1) and renal-specific (NKCC2) isoforms of electroneutral sodium, potassium and chloride cotransporters. These carriers contribute to the pathogenesis of hypertension via regulation of intracellular chloride concentration in vascular smooth muscle and neuronal cells and via sensing chloride concentration in the renal tubular fluid, respectively. Both NKCC1 and NKCC2 are inhibited by furosemide and other high-ceiling diuretics widely used for attenuation of extracellular fluid volume. However, the chronic usage of these compounds for the treatment of hypertension and other volume-expanded disorders may have diverse side-effects due to suppression of myogenic response in microcirculatory beds.
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Affiliation(s)
- Sergei N. Orlov
- Faculty of Biology, M.V. Lomonosov Moscow State University, Russia
- Тomsk State University, Russia
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30
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The hidden hand of chloride in hypertension. Pflugers Arch 2015; 467:595-603. [PMID: 25619794 PMCID: PMC4325190 DOI: 10.1007/s00424-015-1690-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/03/2014] [Accepted: 12/05/2014] [Indexed: 01/10/2023]
Abstract
Among the environmental factors that affect blood pressure, dietary sodium chloride has been studied the most, and there is general consensus that increased sodium chloride intake increases blood pressure. There is accruing evidence that chloride may have a role in blood pressure regulation which may perhaps be even more important than that of Na+. Though more than 85 % of Na+ is consumed as sodium chloride, there is evidence that Na+ and Cl− concentrations do not go necessarily hand in hand since they may originate from different sources. Hence, elucidating the role of Cl− as an independent player in blood pressure regulation will have clinical and public health implications in addition to advancing our understanding of electrolyte-mediated blood pressure regulation. In this review, we describe the evidence that support an independent role for Cl− on hypertension and cardiovascular health.
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31
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Orlov SN, Koltsova SV, Kapilevich LV, Dulin NO, Gusakova SV. Cation-chloride cotransporters: Regulation, physiological significance, and role in pathogenesis of arterial hypertension. BIOCHEMISTRY (MOSCOW) 2015; 79:1546-61. [DOI: 10.1134/s0006297914130070] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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32
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Noda M, Hiyama TY. Sodium sensing in the brain. Pflugers Arch 2014; 467:465-74. [PMID: 25491503 PMCID: PMC4325189 DOI: 10.1007/s00424-014-1662-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/25/2014] [Accepted: 11/27/2014] [Indexed: 12/16/2022]
Abstract
Sodium (Na) homeostasis is crucial for life, and the Na+ level ([Na+]) of body fluids is strictly maintained at a range of 135–145 mM. However, the existence of a [Na+] sensor in the brain has long been controversial until Nax was identified as the molecular entity of the sensor. This review provides an overview of the [Na+]-sensing mechanism in the brain for the regulation of salt intake by summarizing a series of our studies on Nax. Nax is a Na channel expressed in the circumventricular organs (CVOs) in the brain. Among the CVOs, the subfornical organ (SFO) is the principal site for the control of salt intake behavior, where Nax populates the cellular processes of astrocytes and ependymal cells enveloping neurons. A local expression of endothelin-3 in the SFO modulates the [Na+] sensitivity for Nax activation, and thereby Nax is likely to be activated in the physiological [Na+] range. Nax stably interacts with Na+/K+-ATPase whereby Na+ influx via Nax is coupled with activation of Na+/K+-ATPase associated with the consumption of ATP. The consequent activation of anaerobic glucose metabolism of Nax-positive glial cells upregulates the cellular release of lactate, and this lactate functions as a gliotransmitter to activate GABAergic neurons in the SFO. The GABAergic neurons presumably regulate hypothetic neurons involved in the control of salt intake behavior. Recently, a patient with essential hypernatremia caused by autoimmunity to Nax was found. In this case, the hypernatremia was considered to be induced by the complement-mediated cell death in the CVOs, where Nax specifically populates.
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Affiliation(s)
- Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji-cho, Okazaki, 444-8787, Japan,
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33
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Orlov SN, Hamet P. Salt and gene expression: evidence for [Na+]i/[K+]i-mediated signaling pathways. Pflugers Arch 2014; 467:489-98. [PMID: 25479826 DOI: 10.1007/s00424-014-1650-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 10/27/2014] [Accepted: 11/07/2014] [Indexed: 01/11/2023]
Abstract
Our review focuses on the recent data showing that gene transcription and translation are under the control of signaling pathways triggered by modulation of the intracellular sodium/potassium ratio ([Na+]i/[K+]i). Side-by-side with sensing of osmolality elevation by tonicity enhancer-binding protein (TonEBP, NFAT5), [Na+]i/[K+]i-mediated excitation-transcription coupling may contribute to the transcriptomic changes evoked by high salt consumption. This novel mechanism includes the sensing of heightened Na+ concentration in the plasma, interstitial, and cerebrospinal fluids via augmented Na+ influx in the endothelium, immune system cells, and the subfornical organ, respectively. In these cells, [Na+]i/[K+]i ratio elevation, triggered by augmented Na+ influx, is further potentiated by increased production of endogenous Na+,K+-ATPase inhibitors documented in salt-sensitive hypertension.
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Affiliation(s)
- Sergei N Orlov
- Laboratory of Biological Membranes, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskie Gory 1/12, Moscow, 119991, Russia,
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34
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Wu D, He L, Chen L. Apelin/APJ system: a promising therapy target for hypertension. Mol Biol Rep 2014; 41:6691-703. [DOI: 10.1007/s11033-014-3552-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 06/20/2014] [Indexed: 10/25/2022]
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35
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Zablotskii V, Syrovets T, Schmidt ZW, Dejneka A, Simmet T. Modulation of monocytic leukemia cell function and survival by high gradient magnetic fields and mathematical modeling studies. Biomaterials 2014; 35:3164-71. [PMID: 24439412 DOI: 10.1016/j.biomaterials.2013.12.098] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 12/29/2013] [Indexed: 01/09/2023]
Abstract
The influence of spatially modulated high gradient magnetic fields on cellular functions of human THP-1 leukemia cells is studied. We demonstrate that arrays of high-gradient micrometer-sized magnets induce i) cell swelling, ii) prolonged increased ROS production, and iii) inhibit cell proliferation, and iv) elicit apoptosis of THP-1 monocytic leukemia cells in the absence of chemical or biological agents. Mathematical modeling indicates that mechanical stress exerted on the cells by high magnetic gradient forces is responsible for triggering cell swelling and formation of reactive oxygen species followed by apoptosis. We discuss physical aspects of controlling cell functions by focused magnetic gradient forces, i.e. by a noninvasive and nondestructive physical approach.
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Affiliation(s)
| | - Tatiana Syrovets
- Institute of Pharmacology of Natural Products & Clinical Pharmacology, Ulm University, Ulm 89081, Germany
| | - Zoe W Schmidt
- Institute of Pharmacology of Natural Products & Clinical Pharmacology, Ulm University, Ulm 89081, Germany
| | | | - Thomas Simmet
- Institute of Pharmacology of Natural Products & Clinical Pharmacology, Ulm University, Ulm 89081, Germany.
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36
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Abramoff T, Guil MJ, Morales VP, Hope SI, Soria C, Bianciotti LG, Vatta MS. Enhanced assymetrical noradrenergic transmission in the olfactory bulb of deoxycorticosterone acetate-salt hypertensive rats. Neurochem Res 2013; 38:2063-71. [PMID: 23888389 DOI: 10.1007/s11064-013-1114-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 07/10/2013] [Accepted: 07/13/2013] [Indexed: 01/14/2023]
Abstract
The ablation of olfactory bulb induces critical changes in dopamine, and monoamine oxidase activity in the brain stem. Growing evidence supports the participation of this telencephalic region in the regulation blood pressure and cardiovascular activity but little is known about its contribution to hypertension. We have previously reported that in the olfactory bulb of normotensive rats endothelins enhance noradrenergic activity by increasing tyrosine hydroxylase activity and norepinephrine release. In the present study we sought to establish the status of noradrenergic activity in the olfactory bulb of deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Different steps in norepinephrine transmission including tyrosine hydroxylase activity, neuronal norepinephrine release and uptake were assessed in the left and right olfactory bulb of DOCA-salt hypertensive rats. Increased tyrosine hydroxylase activity, and decreased neuronal norepinephrine uptake were observed in the olfactory bulb of DOCA-salt hypertensive rats. Furthermore the expression of tyrosine hydroxylase and its phosphorylated forms were also augmented. Intriguingly, asymmetrical responses between the right and left olfactory bulb of normotensive and hypertensive rats were observed. Neuronal norepinephrine release was increased in the right but not in the left olfactory bulb of DOCA-salt hypertensive rats, whereas non asymmetrical differences were observed in normotensive animals. Present findings indicate that the olfactory bulb of hypertensive rats show an asymmetrical increase in norepinephrine activity. The observed changes in noradrenergic transmission may likely contribute to the onset and/or progression of hypertension in this animal model.
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Affiliation(s)
- Tamara Abramoff
- Cátedra de Fisiología e Instituto de la Química y Metabolismo del Fármaco (IQUIMEFA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, Piso 7, 1113AAD-CABA, Buenos Aires, Argentina
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37
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Regulation of central Na+ detection requires the cooperative action of the NaX channel and α1 Isoform of Na+/K+-ATPase in the Na+-sensor neuronal population. J Neurosci 2013; 33:3067-78. [PMID: 23407962 DOI: 10.1523/jneurosci.4801-12.2013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The median preoptic nucleus (MnPO) holds a strategic position in the hypothalamus. It is adjacent to the third ventricle; hence, it can directly access the ionic composition of the CSF. MnPO neurons play a critical role in hydromineral homeostasis regulation by acting as central sensors of extracellular Na(+) concentration ([Na(+)](ext)). The mechanism underlying Na(+) sensing involves the atypical Na(+) channel, Na(X). Here we sought to determine whether Na(+) influx in Na(+) sensors is actively regulated via interaction with other membrane proteins involved in cellular Na(+) homeostasis, such as Na(+)/K(+)-ATPase. The Na(+)/K(+)-ATPase role was investigated using patch-clamp recordings in rat MnPO dissociated neurons. Na(+) current evoked with hypernatriuric solution was diminished in the absence of ATP/GTP, indicating that Na(+)/K(+)-ATPase play a central role in [Na(+)](ext) detection. Specific blockers of α1 and α3 isoforms of Na(+)/K(+)-ATPase, ouabain or strophanthidin, inhibited this Na(+) current. However, strophanthidin, which selectively blocks the α1 isoform, was more effective in blocking Na(+) current, suggesting that the Na(+)/K(+)-ATPase-α1 isoform is specifically involved in [Na(+)](ext) detection. Although strophanthidin did not alter either the membrane resistance or the Na(+) reversal potential, the conductance and the permeability of the Na(X) channel decreased significantly. Our results suggest that Na(+)/K(+)-ATPase interacts with the Na(X) channel and regulates the high [Na(+)](ext)-evoked Na(+) current via influencing the Na(+) influx rate. This study describes a novel intracellular regulatory pathway of [Na(+)](ext) detection in MnPO neurons. The α1 isoform of Na(+)/K(+)-ATPase acts as a direct regulatory partner of the Na(X) channel and influences Na(+) influx via controlling the Na(+) permeability of the channel.
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Park S, Hong JH, Ohana E, Muallem S. The WNK/SPAK and IRBIT/PP1 pathways in epithelial fluid and electrolyte transport. Physiology (Bethesda) 2013; 27:291-9. [PMID: 23026752 DOI: 10.1152/physiol.00028.2012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Fluid and electrolyte homeostasis is a fundamental physiological function required for survival and is associated with a plethora of diseases when aberrant. Systemic fluid and electrolyte composition is regulated by the kidney, and all secretory epithelia generate biological fluids with defined electrolyte composition by vectorial transport of ions and the obligatory water. A major regulatory pathway that immerged in the last several years is regulation of ion transporters by the WNK/SPAK kinases and IRBIT/PP1 pathways. The IRBIT/PP1 pathway functions to reverse the effects of the WNK/SPAK kinases pathway, as was demonstrated for NBCe1-B and CFTR. Since many transporters involved in fluid and electrolyte homeostasis are affected by PP1 and/or calcineurin, it is possible that WNK/SPAK and IRBIT/PP1 form a common regulatory pathway to tune the activity of fluid and electrolyte transport in response to physiological demands.
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Affiliation(s)
- Seonghee Park
- Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institute of Health, Bethesda, Maryland, USA
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Orlov SN, Koltsova SV, Tremblay J, Baskakov MB, Hamet P. NKCC1 and hypertension: role in the regulation of vascular smooth muscle contractions and myogenic tone. Ann Med 2012; 44 Suppl 1:S111-8. [PMID: 22713139 DOI: 10.3109/07853890.2011.653395] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
High-ceiling diuretics (HCD), known potent inhibitors of housekeeping Na(+),K(+),2Cl cotransporter (NKCC1) and renal-specific NKCC2, decrease [Cl(-)](i), hyperpolarize vascular smooth muscle cells (VSMC), and suppress contractions evoked by modest depolarization, phenylephrine, angiotensin II, and UTP. These actions are absent in nkcc1 (/) knock-out mice, indicating that HCD interact with NKCC1 rather than with other potential targets. These findings also suggest that VSMC-specific inhibitors of NKCC1 may be considered potential pharmacological therapeutic tools in treatment of hypertension. It should be underlined that side by side with attenuation of peripheral resistance and systemic blood pressure, HCD blocked myogenic tone (MT) in renal afferent arterioles. Keeping this in mind, attenuation of MT might be a mechanism underlying the prevalence of end-stage renal disease documented in hypertensive African-Americans with decreased NKCC1 activity and in hypertensive patients subjected to chronic HCD treatment. The role of NKCC1-mediated MT in protection of the brain, heart, and other encapsulated organs deserves further investigation.
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Affiliation(s)
- Sergei N Orlov
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM)-Technôpole Angus, and Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
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40
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Bravo A. I, Michea A. L. Analysis of experimental evidence that shows adverse effects of salt and its relation to hypertension. Medwave 2012. [DOI: 10.5867/medwave.2012.02.5303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Ferreri NR, Hao S, Pedraza PL, Escalante B, Vio CP. Eicosanoids and tumor necrosis factor-alpha in the kidney. Prostaglandins Other Lipid Mediat 2011; 98:101-6. [PMID: 22101002 DOI: 10.1016/j.prostaglandins.2011.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 10/31/2011] [Accepted: 11/03/2011] [Indexed: 12/14/2022]
Abstract
The thick ascending limb of Henle's loop (TAL) is capable of metabolizing arachidonic acid (AA) by cytochrome P450 (CYP450) and cyclooxygenase (COX) pathways and has been identified as a nephron segment that contributes to salt-sensitive hypertension. Previous studies demonstrated a prominent role for CYP450-dependent metabolism of AA to products that inhibited ion transport pathways in the TAL. However, COX-2 is constitutively expressed along all segments of the TAL and is increased in response to diverse stimuli. The ability of Tamm-Horsfall glycoprotein, a selective marker of cortical TAL (cTAL) and medullary (mTAL), to bind TNF and localize it to this nephron segment prompted studies to determine the capacity of mTAL cells to produce TNF and determine its effects on mTAL function. The colocalization of calcium-sensing receptor (CaR) and COX-2 in the TAL supports the notion that activation of CaR induces TNF-dependent COX-2 expression and PGE₂ synthesis in mTAL cells. Additional studies showed that TNF produced by mTAL cells inhibits ⁸⁶Rb uptake, an in vitro correlate of natriuresis, in an autocrine- and COX-2-dependent manner. The molecular mechanism for these effects likely includes inhibition of Na⁺-K⁺-2Cl⁻ cotransporter (NKCC2) expression and trafficking.
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Affiliation(s)
- Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, USA.
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42
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Impaired phosphorylation of Na(+)-K(+)-2Cl(-) cotransporter by oxidative stress-responsive kinase-1 deficiency manifests hypotension and Bartter-like syndrome. Proc Natl Acad Sci U S A 2011; 108:17538-43. [PMID: 21972418 DOI: 10.1073/pnas.1107452108] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Na(+)-K(+)-2Cl(-) cotransporters (NKCCs), including NKCC1 and renal-specific NKCC2, and the Na(+)-Cl(-) cotransporter (NCC) play pivotal roles in the regulation of blood pressure (BP) and renal NaCl reabsorption. Oxidative stress-responsive kinase-1 (OSR1) is a known upstream regulator of N(K)CCs. We generated and analyzed global and kidney tubule-specific (KSP) OSR1 KO mice to elucidate the physiological role of OSR1 in vivo, particularly on BP and kidney function. Although global OSR1(-/-) mice were embryonically lethal, OSR1(+/-) mice had low BP associated with reduced phosphorylated (p) STE20 (sterile 20)/SPS1-related proline/alanine-rich kinase (SPAK) and p-NKCC1 abundance in aortic tissue and attenuated p-NKCC2 abundance with increased total and p-NCC expression in the kidney. KSP-OSR1(-/-) mice had normal BP and hypercalciuria and maintained significant hypokalemia on a low-K(+) diet. KSP-OSR1(-/-) mice exhibited impaired Na(+) reabsorption in the thick ascending loop on a low-Na(+) diet accompanied by remarkably decreased expression of p-NKCC2 and a blunted response to furosemide, an NKCC2 inhibitor. The expression of total SPAK and p-SPAK was significantly increased in parallel to that of total NCC and p-NCC despite unchanged total NKCC2 expression. These results suggest that, globally, OSR1 is involved in the regulation of BP and renal tubular Na(+) reabsorption mainly via the activation of NKCC1 and NKCC2. In the kidneys, NKCC2 but not NCC is the main target of OSR1 and the reduced p-NKCC2 in KSP-OSR1(-/-) mice may lead to a Bartter-like syndrome.
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Malekin SI, Kotelevtsev SV, Gavrilova SA, Fadyukova OE, Golubeva AV, Grinchenko MI, Koshelev VB, Kotelevtsev YV, Hamet P, Orlov SN. Long-term normalization of blood pressure in SHR and 1-kidney 1-clip rats by synthetic precursor of stable PAF analogue without systemic effects in normotensive rats. ACTA ACUST UNITED AC 2011; 18:151-7. [PMID: 20888741 DOI: 10.1016/j.pathophys.2010.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 08/17/2010] [Indexed: 10/19/2022]
Abstract
This study characterized the actions of the newly synthesized PAF precursor 1-hexadecyl-2-alkylcarbamoyl-glycerol (HAG) on blood pressure (BP) in male spontaneously hypertensive rats (SHR), SHR-stroke prone (SHRSP) and Wistar rats with 1-kidney 1-clip (1K1C) renovascular hypertension used as experimental models of human primary and secondary hypertension. Systolic blood pressure (SBP) in the tail artery and mean arterial pressure (MAP) in the abdominal aorta were measured by tail plethysmography and invasive pressure transducer, respectively. Intravenous treatment with 1mg/kg HAG in SHR resulted in a rapid decline of MAP from 151±4 to 127±4mmHg in 50min (p<0.001) that was maintained for 24h after injection (128±5mmHg, p<0.01). We also observed a profound hypotensive effect of HAG in SHRSP but not in normotensive Wistar rats. In 1K1C rats, the magnitude of the BP decline evoked by HAG was correlated with MAP measured before drug administration (R=0.74, p<0.005). In 1K1C rats with SBP>140mmHg, 5mg/kg/48h HAG, given orally for 14 days, decreased SBP by 20-30mmHg without an increase in the death rate and other adverse effects. Thus, our results show that intravenous and oral administration of HAG led to a long-lasting reduction of BP in experimental models of primary and secondary hypertension. In contrast to PAF and its derivatives, the hypotensive action of HAG was preserved for 24h after a single administration, was absent in normotensive animals, and was not accompanied by visible side-effects, at least during 2 weeks of treatment.
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Koltsova SV, Platonova A, Maksimov GV, Mongin AA, Grygorczyk R, Orlov SN. Activation of P2Y receptors causes strong and persistent shrinkage of C11-MDCK renal epithelial cells. Am J Physiol Cell Physiol 2011; 301:C403-12. [PMID: 21562307 DOI: 10.1152/ajpcell.00018.2011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Purinergic receptors activate diverse signaling cascades and regulate the activity of cell volume-sensitive ion transporters. However, the effects of ATP and other agonists of P2 receptors on cell volume dynamics are only scarcely studied. In the present work, we used the recently developed dual-image surface reconstruction technique to explore the influence of purinergic agonists on cell volume in the C11-Madin-Darby canine kidney cell line resembling intercalated cells from kidney collecting ducts. Unexpectedly, we found that ATP and UTP triggered very robust (55-60%) cell shrinkage that lasted up to 2 h after agonist washout. Purinergic regulation of cell volume required increases in intracellular Ca(2+) and could be partially mimicked by the Ca(2+)-ionophore ionomycin or activation of protein kinase C by 4β-phorbol 12-myristate 13-acetate. Cell shrinkage was accompanied by strong reductions in intracellular K(+) and Cl(-) content measured using steady-state (86)Rb(+) and (36)Cl(-) distribution. Both shrinkage and ion efflux in ATP-treated cells were prevented by the anion channel blocker 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) and by the BK(Ca) channel inhibitors charybdotoxin, iberiotoxin, and paxilline. To evaluate the significance of cell-volume changes in purinergic signaling, we measured the impact of ATP on the expression of the immediate-early gene c-Fos. Thirty-minute treatment with ATP increased c-Fos immunoreactivity by approximately fivefold, an effect that was strongly inhibited by charybdotoxin and completely prevented by NPPB. Overall, our findings suggest that ATP-induced cell-volume changes are partially responsible for the physiological actions of purinergic agonists.
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Affiliation(s)
- Svetlana V Koltsova
- Research Centre, Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal, Quebec, Canada
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Watanabe T, Takei Y. Environmental factors responsible for switching on the SO₄²⁻ excretory system in the kidney of seawater eels. Am J Physiol Regul Integr Comp Physiol 2011; 301:R402-11. [PMID: 21543635 DOI: 10.1152/ajpregu.00624.2010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Eels are unique in that they maintain lower plasma SO(4)(2-) concentration in SO(4)(2-)-rich (∼30 mM) seawater (SW) than in SO(4)(2-)-poor (<0.3 mM) freshwater (FW), showing drastic changes in SO(4)(2-) regulation between FW and SW. We previously showed that the expression of renal SO(4)(2-) transporter genes, FW-specific Slc13a1 and SW-specific Slc26a6a, changes profoundly after transfer of FW eels to SW, which results in the decrease in plasma SO(4)(2-) concentration after 3 days in SW. In this study, we attempted to identify the environmental factor(s) that trigger the switching of SO(4)(2-) regulation using changes in plasma and urine SO(4)(2-) concentrations and expression of the transporter genes as markers. Transfer of FW eels to 30 mM SO(4)(2-) or transfer of SW eels to SO(4)(2-)-free SW did not change the SO(4)(2-) regulation. Major divalent cations in SW, Mg(2+) (50 mM) and Ca(2+) (10 mM), were also ineffective, but 50 mM NaCl was effective for switching the SO(4)(2-) regulation. Further analyses using choline-Cl and Na-gluconate showed that Cl(-) is a primary factor and Na(+) is permissive for the Cl(-) effect. Since plasma SO(4)(2-) and Cl(-) concentrations were inversely correlated, we injected various solutions into the blood and found that Cl(-) alone triggered the switching from FW to SW-type regulation. Furthermore, the inhibitor of Na-Cl cotransporter (NCC) added to media significantly impaired the expression of SW-specific Slc26a6a in 150 mM NaCl. In summary, it appears that Cl(-) ions in SW are taken up into the circulation via the NCC together with Na(+), and the resultant increase in plasma Cl(-) concentration enhances SO(4)(2-) excretion by the kidney through downregulation of absorptive Slc13a1 and upregulation of excretory Slc26a6a, resulting in low plasma SO(4)(2-) concentration in SW.
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Affiliation(s)
- Taro Watanabe
- Laboratory of Physiology, Department of Marine Bioscience, Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan.
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Abstract
The assessment of salt sensitivity of blood pressure is difficult because of the lack of universal consensus on definition. Regardless of the variability in the definition of salt sensitivity, increased salt intake, independent of the actual level of blood pressure, is also a risk factor for cardiovascular morbidity and mortality and kidney disease. A modest reduction in salt intake results in an immediate decrease in blood pressure, with long-term beneficial consequences. However, some have suggested that dietary sodium restriction may not be beneficial to everyone. Thus, there is a need to distinguish salt-sensitive from salt-resistant individuals, but it has been difficult to do so with phenotypic studies. Therefore, there is a need to determine the genes that are involved in salt sensitivity. This review focuses on genes associated with salt sensitivity, with emphasis on the variants associated with salt sensitivity in humans that are not due to monogenic causes. Special emphasis is given to gene variants associated with salt sensitivity whose protein products interfere with cell function and increase blood pressure in transgenic mice.
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Affiliation(s)
- Hironobu Sanada
- Division of Health Science Research, Fukushima Welfare Federation of Agricultural Cooperatives, Fukushima, Japan.
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Kainate receptor modulation by sodium and chloride. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 717:93-113. [PMID: 21713670 DOI: 10.1007/978-1-4419-9557-5_9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The kainate-type glutamate receptor displays strong modulation by monovalent anions and cations. This modulation is independent of permeation of the ion channel. Instead, structural, computational and biophysical evidence shows that receptor activity is controlled by binding of sodium and chloride ions at sites that stabilize active dimers of glutamate binding domains. Modulation by monovalent ions is a surprisingly general property across ion channel families. However, evidence of a physiological role for ion-dependent effects on glutamate receptors is lacking, perhaps reflecting the adventitious use of ions as structural components of the kainate receptor. "ergo, Hercules, vita humanior sine sale non quit degree […]" "Heaven known, a civilized life is impossible without salt" -Pliny the Elder, Natural History XXXI 88.
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Coon S, Kekuda R, Saha P, Sundaram U. Reciprocal regulation of the primary sodium absorptive pathways in rat intestinal epithelial cells. Am J Physiol Cell Physiol 2010; 300:C496-505. [PMID: 21148403 DOI: 10.1152/ajpcell.00292.2010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sodium absorption in the mammalian small intestine occurs predominantly by two primary pathways that include Na/H exchange (NHE3) and Na-glucose cotransport (SGLT1) on the brush border membrane (BBM) of villus cells. However, whether NHE3 and SGLT1 function together to regulate intestinal sodium absorption is unknown. Nontransformed small intestinal epithelial cells (IEC-18) were transfected with either NHE3 or SGLT1 small interfering RNAs (siRNAs) and were grown in confluent monolayers on transwell plates to measure the effects on Na absorption. Uptake studies were performed as well as molecular studies to determine the effects on NHE3 and SGLT1 activity. When IEC-18 monolayers were transfected with silencing NHE3 RNA, the cells demonstrated decreased NHE3 activity as well as decreased NHE3 mRNA and protein. However, in NHE3 siRNA-transected cells, SGLT1 activity, mRNA, and protein in the BBM were significantly increased. Thus, inhibition of NHE3 expression regulates the expression and function of SGLT1 in the BBM of intestinal epithelial cells. In addition, IEC-18 cells transected with silencing SGLT1 RNA demonstrated an inhibition of Na-dependent glucose uptake and a decrease in SGLT1 activity, mRNA, and protein levels. However, in these cells, Na/H exchange activity was significantly increased. Furthermore, NHE3 mRNA and protein levels were also increased. Therefore, the inhibition of SGLT1 expression stimulates the transcription and function of NHE3 and vice versa in the BBM of intestinal epithelial cells. Thus this study demonstrates that the major sodium absorptive pathways together function to regulate sodium absorption in epithelial cells.
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Affiliation(s)
- Steven Coon
- West Virginia Univ. School of Medicine, Morgantown, WV 26506, USA
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Yang SS, Lo YF, Wu CC, Lin SW, Yeh CJ, Chu P, Sytwu HK, Uchida S, Sasaki S, Lin SH. SPAK-knockout mice manifest Gitelman syndrome and impaired vasoconstriction. J Am Soc Nephrol 2010; 21:1868-77. [PMID: 20813865 DOI: 10.1681/asn.2009121295] [Citation(s) in RCA: 214] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Polymorphisms in the gene encoding sterile 20/SPS1-related proline/alanine-rich kinase (SPAK) associate with hypertension susceptibility in humans. SPAK interacts with WNK kinases to regulate the Na(+)-K(+)-2Cl(-) and Na(+)-Cl(-) co-transporters [collectively, N(K)CC]. Mutations in WNK1/4 and N(K)CC can cause changes in BP and dyskalemia in humans, but the physiologic role of SPAK in vivo is unknown. We generated and analyzed SPAK-null mice by targeting disruption of exons 9 and 10 of SPAK. Compared with SPAK(+/+) littermates, SPAK(+/-) mice exhibited hypotension without significant electrolyte abnormalities, and SPAK(-/-) mice not only exhibited hypotension but also recapitulated Gitelman syndrome with hypokalemia, hypomagnesemia, and hypocalciuria. In the kidney tissues of SPAK(-/-) mice, the expression of total and phosphorylated (p-)NCC was markedly decreased, but that of p-OSR1, total NKCC2, and p-NKCC2 was significantly increased. We observed a blunted response to thiazide but normal response to furosemide in SPAK(-/-) mice. In aortic tissues, total NKCC1 expression was increased but p-NKCC1 was decreased in SPAK-deficient mice. Both SPAK(+/-) and SPAK(-/-) mice had impaired responses to the selective α(1)-adrenergic agonist phenylephrine and the NKCC1 inhibitor bumetanide, suggesting that impaired aortic contractility may contribute to the hypotension of SPAK-null mice. In summary, SPAK-null mice have defects of NCC in the kidneys and NKCC1 in the blood vessels, leading to hypotension through renal salt wasting and vasodilation. SPAK may be a promising target for antihypertensive therapy.
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Affiliation(s)
- Sung-Sen Yang
- Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
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Roysommuti S, Malila P, Lerdweeraphon W, Jirakulsomchok D, Wyss JM. Perinatal taurine exposure alters renal potassium excretion mechanisms in adult conscious rats. J Biomed Sci 2010; 17 Suppl 1:S29. [PMID: 20804604 PMCID: PMC2994394 DOI: 10.1186/1423-0127-17-s1-s29] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Perinatal taurine exposure has long-term effects on the arterial pressure and renal function. This study tests its influence on renal potassium excretion in young adult, conscious rats. Female Sprague-Dawley rats were fed normal rat chow and given water alone (C), 3% beta-alanine in water (taurine depletion, TD) or 3% taurine in water (taurine supplementation, TS), either from conception until delivery (fetal period; TDF or TSF) or from delivery until weaning (lactation period; TDL or TSL). In Experiment 1, male offspring were fed normal rat chow and tap water, while in Experiment 2, beta-alanine and taurine were treated from conception until weaning and then female pups were fed normal rat chow and 5% glucose in drinking water (CG, TDG or TSG) or water alone (CW, TDW or TSW). At 7-8 weeks of age, renal potassium excretion was measured at rest and after an acute saline load (5% of body weight) in conscious, restrained rats. Although all male groups displayed similar renal potassium excretion, TSF rats slightly increased fractional potassium excretion at rest but not in response to saline load, whereas TDF did the opposite. Plasma potassium concentration was only slightly altered by the diet manipulations. In female offspring, none of the perinatal treatments significantly altered renal potassium excretion at rest or after saline load. High sugar intake slightly decreased potassium excretion at rest in TDG and TSG, but only the TDG group displayed a decreased response to saline load. The present data indicates that perinatal taurine exposure only mildly influences renal potassium excretion in adult male and female rats.
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Affiliation(s)
- Sanya Roysommuti
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
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