1
|
Castro PC, Santos-Rios TM, Martins FL, Crajoinas RO, Caetano MV, Lessa LMA, Luchi WM, McCormick JA, Girardi ACC. Renal upregulation of NCC counteracts empagliflozin-mediated NHE3 inhibition in normotensive but not in hypertensive male rat. Am J Physiol Cell Physiol 2024; 326:C1573-C1589. [PMID: 38557357 DOI: 10.1152/ajpcell.00351.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 03/21/2024] [Accepted: 03/21/2024] [Indexed: 04/04/2024]
Abstract
Sodium-glucose cotransporter-2 inhibitors (SGLT2i) reduce blood pressure (BP) in patients with hypertension, yet the precise molecular mechanisms remain elusive. SGLT2i inhibits proximal tubule (PT) NHE3-mediated sodium reabsorption in normotensive rodents, yet no hypotensive effect is observed under this scenario. This study examined the effect of empagliflozin (EMPA) on renal tubular sodium transport in normotensive and spontaneously hypertensive rats (SHRs). It also tested the hypothesis that EMPA-mediated PT NHE3 inhibition in normotensive rats is associated with upregulation of distal nephron apical sodium transporters. EMPA administration for 14 days reduced BP in 12-wk-old SHRs but not in age-matched Wistar rats. PT NHE3 activity was inhibited by EMPA treatment in both Wistar and SHRs. In Wistar rats, EMPA increased NCC activity, mRNA expression, protein abundance, and phosphorylation levels, but not in SHRs. SHRs showed higher NKCC2 activity and an abundance of cleaved ENaC α and γ subunits compared with Wistar rats, none of which were affected by EMPA. Another set of male Wistar rats was treated with EMPA, the NCC inhibitor hydrochlorothiazide (HCTZ), and EMPA combined with HCTZ or vehicle for 14 days. In these rats, BP reduction was observed only with combined EMPA and HCTZ treatment, not with either drug alone. These findings suggest that NCC upregulation counteracts EMPA-mediated inhibition of PT NHE3 in male normotensive rats, maintaining their baseline BP. Moreover, the reduction of NHE3 activity without further upregulation of major apical sodium transporters beyond the PT may contribute to the BP-lowering effect of SGLT2i in experimental models and patients with hypertension.NEW & NOTEWORTHY This study suggests that reduced NHE3-mediated sodium reabsorption in the renal proximal tubule may account, at least in part, for the BP-lowering effect of SGLT2 inhibitors in the setting of hypertension. It also demonstrates that chronic treatment with SGLT2 inhibitors upregulates NCC activity, phosphorylation, and expression in the distal tubule of normotensive but not hypertensive rats. SGLT2 inhibitor-mediated upregulation of NCC seems crucial to counteract proximal tubule natriuresis in subjects with normal BP.
Collapse
Affiliation(s)
- Paulo C Castro
- Laboratório de Genética e Cardiologia Molecular, Instituto do Coração (InCor), Hospital das Clínicas HCFMUSP, São Paulo, Brazil
| | - Thiago M Santos-Rios
- Laboratório de Genética e Cardiologia Molecular, Instituto do Coração (InCor), Hospital das Clínicas HCFMUSP, São Paulo, Brazil
| | - Flavia L Martins
- Laboratório de Genética e Cardiologia Molecular, Instituto do Coração (InCor), Hospital das Clínicas HCFMUSP, São Paulo, Brazil
| | - Renato O Crajoinas
- Laboratório de Genética e Cardiologia Molecular, Instituto do Coração (InCor), Hospital das Clínicas HCFMUSP, São Paulo, Brazil
| | - Marcos V Caetano
- Laboratório de Genética e Cardiologia Molecular, Instituto do Coração (InCor), Hospital das Clínicas HCFMUSP, São Paulo, Brazil
| | - Lucília M A Lessa
- Instituto Superior de Ciências Biomédicas, Universidade Estadual do Ceará, Fortaleza, Brazil
| | - Weverton M Luchi
- Hospital Universitário Cassiano Antonio Moraes, Universidade Federal do Espírito Santo (HUCAM-UFES), Vitória, Brazil
| | - James A McCormick
- Division of Nephrology and Hypertension, Department of Medicine, Oregon Health and Science University, Portland, Oregon, United States
| | - Adriana C C Girardi
- Laboratório de Genética e Cardiologia Molecular, Instituto do Coração (InCor), Hospital das Clínicas HCFMUSP, São Paulo, Brazil
| |
Collapse
|
2
|
Capolongo G, Damiano S, Suzumoto Y, Zacchia M, Rizzo M, Zona E, Pollastro RM, Simeoni M, Ciarcia R, Trepiccione F, Capasso G. Cyclosporin-induced hypertension is associated with the up-regulation of Na+-K+-2Cl- cotransporter (NKCC2). Nephrol Dial Transplant 2024; 39:297-304. [PMID: 37463050 PMCID: PMC10828191 DOI: 10.1093/ndt/gfad161] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Indexed: 02/01/2024] Open
Abstract
BACKGROUND The use of cyclosporin A (CsA) is hampered by the development of nephrotoxicity including hypertension, which is partially dependent on renal sodium retention. To address this issue, we have investigated in vivo sodium reabsorption in different nephron segments of CsA-treated rats through micropuncture study coupled to expression analyses of sodium transporters. To translate the findings in rats to human, kidney-transplanted patients having CsA treatment were enrolled in the study. METHODS Adult male Sprague-Dawley rats were treated with CsA (15 mg/kg/day) for 21 days, followed by micropuncture study and expression analyses of sodium transporters. CsA-treated kidney-transplanted patients with resistant hypertension were challenged with 50 mg furosemide. RESULTS CsA-treated rats developed hypertension associated with reduced glomerular filtration rate. In vivo microperfusion study demonstrated a significant decrease in rate of absolute fluid reabsorption in the proximal tubule but enhanced sodium reabsorption in the thick ascending limb of Henle's loop (TAL). Expression analyses of sodium transporters at the same nephron segments further revealed a reduction in Na+-H+ exchanger isoform 3 (NHE3) in the renal cortex, while TAL-specific, furosemide-sensitive Na+-K+-2Cl- cotransporter (NKCC2) and NHE3 were significantly upregulated in the inner stripe of outer medulla. CsA-treated patients had a larger excretion of urinary NKCC2 protein at basal condition, and higher diuretic response to furosemide, showing increased FeNa+, FeCl- and FeCa2+ compared with both healthy controls and FK506-treated transplanted patients. CONCLUSION Altogether, these findings suggest that up-regulation of NKCC2 along the TAL facilitates sodium retention and contributes to the development of CsA-induced hypertension.
Collapse
Affiliation(s)
- Giovanna Capolongo
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Sara Damiano
- Department of Veterinary Medicine and Animal Productions, University of Naples, Naples, Italy
| | - Yoko Suzumoto
- Biogem, Institute of Molecular Biology and Genetics, Ariano Irpino, Italy
| | - Miriam Zacchia
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Maria Rizzo
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Enrica Zona
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Rosa Maria Pollastro
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Mariadelina Simeoni
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Roberto Ciarcia
- Department of Veterinary Medicine and Animal Productions, University of Naples, Naples, Italy
| | - Francesco Trepiccione
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
- Biogem, Institute of Molecular Biology and Genetics, Ariano Irpino, Italy
| | - Giovambattista Capasso
- Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli”, Naples, Italy
- Biogem, Institute of Molecular Biology and Genetics, Ariano Irpino, Italy
| |
Collapse
|
3
|
Mogilnicka I, Jaworska K, Koper M, Maksymiuk K, Szudzik M, Radkiewicz M, Chabowski D, Ufnal M. Hypertensive rats show increased renal excretion and decreased tissue concentrations of glycine betaine, a protective osmolyte with diuretic properties. PLoS One 2024; 19:e0294926. [PMID: 38166023 PMCID: PMC10760924 DOI: 10.1371/journal.pone.0294926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 11/10/2023] [Indexed: 01/04/2024] Open
Abstract
Hypertension leads to water-electrolyte disturbances and end-organ damage. Betaine is an osmolyte protecting cells against electrolyte imbalance and osmotic stress, particularly in the kidneys. This study aimed to evaluate tissue levels and hemodynamic and renal effects of betaine in normotensive and hypertensive rats. Betaine levels were assessed using high-performance liquid chromatography-mass spectrometry (HPLC-MS) in normotensive rats (Wistar-Kyoto, WKYs) and Spontaneously Hypertensive rats (SHRs), a model of genetic hypertension. Acute effects of IV betaine on blood pressure, heart rate, and minute diuresis were evaluated. Gene and protein expression of chosen kidney betaine transporters (SLC6a12 and SLC6a20) were assessed using real-time PCR and Western blot. Compared to normotensive rats, SHRs showed significantly lower concentration of betaine in blood serum, the lungs, liver, and renal medulla. These changes were associated with higher urinary excretion of betaine in SHRs (0.20 ± 0.04 vs. 0.09 ± 0.02 mg/ 24h/ 100g b.w., p = 0.036). In acute experiments, betaine increased diuresis without significantly affecting arterial blood pressure. The diuretic response was greater in SHRs than in WKYs. There were no significant differences in renal expression of betaine transporters between WKYs and SHRs. Increased renal excretion of betaine contributes to decreased concentration of the protective osmolyte in tissues of hypertensive rats. These findings pave the way for studies evaluating a causal relation between depleted betaine and hypertensive organ damage, including kidney injury.
Collapse
Affiliation(s)
- Izabella Mogilnicka
- Department of Experimental Physiology and Pathophysiology, Laboratory of the Centre for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Kinga Jaworska
- Department of Experimental Physiology and Pathophysiology, Laboratory of the Centre for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Mateusz Koper
- Department of Experimental Physiology and Pathophysiology, Laboratory of the Centre for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Klaudia Maksymiuk
- Department of Experimental Physiology and Pathophysiology, Laboratory of the Centre for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Mateusz Szudzik
- Department of Experimental Physiology and Pathophysiology, Laboratory of the Centre for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Mariusz Radkiewicz
- Mass Spectrometry Laboratory, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Dawid Chabowski
- Department of Experimental Physiology and Pathophysiology, Laboratory of the Centre for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Marcin Ufnal
- Department of Experimental Physiology and Pathophysiology, Laboratory of the Centre for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| |
Collapse
|
4
|
Habas E, Al Adab A, Arryes M, Alfitori G, Farfar K, Habas AM, Akbar RA, Rayani A, Habas E, Elzouki A. Anemia and Hypoxia Impact on Chronic Kidney Disease Onset and Progression: Review and Updates. Cureus 2023; 15:e46737. [PMID: 38022248 PMCID: PMC10631488 DOI: 10.7759/cureus.46737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2023] [Indexed: 12/01/2023] Open
Abstract
Chronic kidney disease (CKD) is caused by hypoxia in the renal tissue, leading to inflammation and increased migration of pathogenic cells. Studies showed that leukocytes directly sense hypoxia and respond by initiating gene transcription, encoding the 2-integrin adhesion molecules. Moreover, other mechanisms participate in hypoxia, including anemia. CKD-associated anemia is common, which induces and worsens hypoxia, contributing to CKD progression. Anemia correction can slow CKD progression, but it should be cautiously approached. In this comprehensive review, the underlying pathophysiology mechanisms and the impact of renal tissue hypoxia and anemia in CKD onset and progression will be reviewed and discussed in detail. Searching for the latest updates in PubMed Central, Medline, PubMed database, Google Scholar, and Google search engines were conducted for original studies, including cross-sectional studies, cohort studies, clinical trials, and review articles using different keywords, phrases, and texts such as "CKD progression, anemia in CKD, CKD, anemia effect on CKD progression, anemia effect on CKD progression, and hypoxia and CKD progression". Kidney tissue hypoxia and anemia have an impact on CKD onset and progression. Hypoxia causes nephron cell death, enhancing fibrosis by increasing interstitium protein deposition, inflammatory cell activation, and apoptosis. Severe anemia correction improves life quality and may delay CKD progression. Detection and avoidance of the risk factors of hypoxia prevent recurrent acute kidney injury (AKI) and reduce the CKD rate. A better understanding of kidney hypoxia would prevent AKI and CKD and lead to new therapeutic strategies.
Collapse
Affiliation(s)
| | - Aisha Al Adab
- Internal Medicine, Hamad General Hospital, Doha, QAT
| | - Mehdi Arryes
- Internal Medicine, Hamad General Hospital, Doha, QAT
| | | | | | - Ala M Habas
- Internal Medicine, Tripoli University, Tripoli, LBY
| | - Raza A Akbar
- Internal Medicine, Hamad General Hospital, Doha, QAT
| | - Amnna Rayani
- Hemat-oncology Department, Pediatric Tripoli Hospital, Tripoli University, Tripoli, LBY
| | - Eshrak Habas
- Internal Medicine, Tripoli University, Tripoli, LBY
| | | |
Collapse
|
5
|
Jones G, Zeng L, Kim J. Mechanism-Based Pharmacokinetic Modeling of Absorption and Disposition of a Deferoxamine-Based Nanochelator in Rats. Mol Pharm 2023; 20:481-490. [PMID: 36378830 DOI: 10.1021/acs.molpharmaceut.2c00737] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Deferoxamine (DFO) is an effective FDA-approved iron chelator. However, its use is considerably limited by off-target toxicities and an extremely cumbersome dose regimen with daily infusions. The recent development of a deferoxamine-based nanochelator (DFO-NP) with selective renal excretion has shown promise in ameliorating animal models of iron overload with a substantially improved safety profile. To further the preclinical development of this promising nanochelator and to inform on the feasibility of clinical development, it is necessary to fully characterize the dose and administration-route-dependent pharmacokinetics and to develop predictive pharmacokinetic (PK) models describing absorption and disposition. Herein, we have evaluated the absorption, distribution, and elimination of DFO-NPs after intravenous and subcutaneous (SC) injection at therapeutically relevant doses in Sprague Dawley rats. We also characterized compartment-based model structures and identified model-based parameters to quantitatively describe the PK of DFO-NPs. Our modeling efforts confirmed that disposition could be described using a three-compartment mamillary model with elimination and saturable reabsorption both occurring from the third compartment. We also determined that absorption was nonlinear and best described by parallel saturable and first-order processes. Finally, we characterized a novel pathway for saturable SC absorption of an ultrasmall organic nanoparticle directly into the systemic circulation, which offers a novel strategy for improving drug exposure for nanotherapeutics.
Collapse
Affiliation(s)
- Gregory Jones
- Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - Lingxue Zeng
- Department of Biomedical and Nutritional Sciences, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
| | - Jonghan Kim
- Department of Biomedical and Nutritional Sciences, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
| |
Collapse
|
6
|
Verma N, Despa F. The association between renal accumulation of pancreatic amyloid-forming amylin and renal hypoxia. Front Endocrinol (Lausanne) 2023; 14:1104662. [PMID: 36875454 PMCID: PMC9978768 DOI: 10.3389/fendo.2023.1104662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 02/06/2023] [Indexed: 02/18/2023] Open
Abstract
Chronic kidney disease (CKD) is increasing worldwide and is associated with diabetic states (obesity, prediabetes and type-2 diabetes mellitus). The kidney is intrinsically susceptible to low oxygen (hypoxia) and renal hypoxia plays a vital role in the progression of CKD. Recent studies suggest an association between CKD and renal deposition of amyloid-forming amylin secreted from the pancreas. Renal accumulation of amyloid-forming amylin is associated with hypertension, mitochondrial dysfunction, increased production of reactive oxygen species (ROS) and activation of hypoxia signaling in the kidney. In this review we will discuss potential associations between renal amylin amyloid accumulation, hypertension, and mechanism of hypoxia-induced kidney dysfunction, including activation of hypoxia-inducible factors (HIFs) and mitochondrial dysfunction.
Collapse
|
7
|
Kelley RC, Lapierre SS, Muscato DR, Hahn D, Christou DD, Ferreira LF. Cardiac and respiratory muscle responses to dietary N-acetylcysteine in rats consuming a high-saturated fat, high-sucrose diet. Exp Physiol 2022; 107:1312-1325. [PMID: 35938289 PMCID: PMC9633399 DOI: 10.1113/ep090332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 07/22/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? This study addresses whether a high-fat, high-sucrose diet causes cardiac and diaphragm muscle abnormalities in male rats and whether supplementation with the antioxidant N-acetylcysteine reverses diet-induced dysfunction. What is the main finding and its importance? N-Acetylcysteine attenuated the effects of high-fat, high-sucrose diet on markers of cardiac hypertrophy and diastolic dysfunction, but neither high-fat, high-sucrose diet nor N-acetylcysteine affected the diaphragm. These results support the use of N-acetylcysteine to attenuate cardiovascular dysfunction induced by a 'Western' diet. ABSTRACT Individuals with overweight or obesity display respiratory and cardiovascular dysfunction, and oxidative stress is a causative factor in the general aetiology of obesity and of skeletal and cardiac muscle pathology. Thus, this preclinical study aimed to define diaphragmatic and cardiac morphological and functional alterations in response to an obesogenic diet in rats and the therapeutic potential of an antioxidant supplement, N-acetylcysteine (NAC). Young male Wistar rats consumed ad libitum a 'lean' or high-saturated fat, high-sucrose (HFHS) diet for ∼22 weeks and were randomized to control or NAC (2 mg/ml in the drinking water) for the last 8 weeks of the dietary intervention. We then evaluated diaphragmatic and cardiac morphology and function. Neither HFHS diet nor NAC supplementation affected diaphragm-specific force, peak power or morphology. Right ventricular weight normalized to estimated body surface area, left ventricular fractional shortening and posterior wall maximal shortening velocity were higher in HFHS compared with lean control animals and not restored by NAC. In HFHS rats, the elevated deceleration rate of early transmitral diastolic velocity was prevented by NAC. Our data showed that the HFHS diet did not compromise diaphragmatic muscle morphology or in vitro function, suggesting other possible contributors to breathing abnormalities in obesity (e.g., abnormalities of neuromuscular transmission). However, the HFHS diet resulted in cardiac functional and morphological changes suggestive of hypercontractility and diastolic dysfunction. Supplementation with NAC did not affect diaphragm morphology or function but attenuated some of the cardiac abnormalities in the rats receiving the HFHS diet.
Collapse
Affiliation(s)
- Rachel C. Kelley
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Stephanie S. Lapierre
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Derek R. Muscato
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Dongwoo Hahn
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Demetra D. Christou
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Leonardo F. Ferreira
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| |
Collapse
|
8
|
Nwia SM, Li XC, Leite APDO, Hassan R, Zhuo JL. The Na +/H + Exchanger 3 in the Intestines and the Proximal Tubule of the Kidney: Localization, Physiological Function, and Key Roles in Angiotensin II-Induced Hypertension. Front Physiol 2022; 13:861659. [PMID: 35514347 PMCID: PMC9062697 DOI: 10.3389/fphys.2022.861659] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/25/2022] [Indexed: 01/29/2023] Open
Abstract
The sodium (Na+)/hydrogen (H+) exchanger 3 (NHE3) is one of the most important Na+/H+ antiporters in the small intestines of the gastrointestinal tract and the proximal tubules of the kidney. The roles of NHE3 in the regulation of intracellular pH and acid-base balance have been well established in cellular physiology using in vitro techniques. Localized primarily on the apical membranes in small intestines and proximal tubules, the key action of NHE3 is to facilitate the entry of luminal Na+ and the extrusion of intracellular H+ from intestinal and proximal tubule tubular epithelial cells. NHE3 is, directly and indirectly, responsible for absorbing the majority of ingested Na+ from small and large intestines and reabsorbing >50% of filtered Na+ in the proximal tubules of the kidney. However, the roles of NHE3 in the regulation of proximal tubular Na+ transport in the integrative physiological settings and its contributions to the basal blood pressure regulation and angiotensin II (Ang II)-induced hypertension have not been well studied previously due to the lack of suitable animal models. Recently, novel genetically modified mouse models with whole-body, kidney-specific, or proximal tubule-specific deletion of NHE3 have been generated by us and others to determine the critical roles and underlying mechanisms of NHE3 in maintaining basal body salt and fluid balance, blood pressure homeostasis, and the development of Ang II-induced hypertension at the whole-body, kidney, or proximal tubule levels. The objective of this invited article is to review, update, and discuss recent findings on the critical roles of intestinal and proximal tubule NHE3 in maintaining basal blood pressure homeostasis and their potential therapeutic implications in the development of angiotensin II (Ang II)-dependent hypertension.
Collapse
Affiliation(s)
- Sarah M. Nwia
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Xiao Chun Li
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Ana Paula de Oliveira Leite
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Rumana Hassan
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Jia Long Zhuo
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA, United States,Department of Physiology, Tulane University School of Medicine, New Orleans, LA, United States,*Correspondence: Jia Long Zhuo,
| |
Collapse
|
9
|
Craig A, Gafane-Matemane L, Smith W, Mels C, Uys L, Breet Y, Brits S, Mokwatsi G, Hanssen H, Kruger R. Elevated blood pressure positively associates with alpha-1 microglobulin in prepubescent children: the ExAMIN Youth SA study. J Hypertens 2022; 40:136-142. [PMID: 34857706 DOI: 10.1097/hjh.0000000000002989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVES AND METHODS Hypertension is a growing health concern in childhood populations and individuals of African descent. As the kidneys play a significant role in blood pressure regulation, we compared alpha-1 microglobulin (A1M) as a marker of proximal tubular function between young healthy black and white children (n = 957; aged: 5-9 years) and explored its association with blood pressure. RESULTS The black children had higher levels of A1M (P < 0.001) and higher DBP (P < 0.001) when compared with their white counterparts. In multiple regression analysis, SBP (adj. R2 = 0.173, β = 0.151; P < 0.001) and DBP (adj. R2 = 0.110, β = 0.179; P < 0.001) associated positively with A1M in the black children. In binary logistic regression, each standard deviation increase in A1M increased the odds of having elevated blood pressure by 28% (P = 0.002) in the black group, independent of age, sex, BMI z-score and body height. No significance was reached in the white children. CONCLUSION Our findings highlight the importance of a marker of proximal tubular function, especially in children of black ethnicity, in the setting of elevated blood pressure. Early childhood screening for elevated blood pressure remains essential in order to promote primary prevention of hypertension and early onset kidney damage in children.
Collapse
Affiliation(s)
| | - Lebo Gafane-Matemane
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Wayne Smith
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Carina Mels
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Lisa Uys
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Yolandi Breet
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | | | - Gonste Mokwatsi
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Henner Hanssen
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Ruan Kruger
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| |
Collapse
|
10
|
Nox4 Maintains Blood Pressure during Low Sodium Diet. Antioxidants (Basel) 2021; 10:antiox10071103. [PMID: 34356336 PMCID: PMC8301203 DOI: 10.3390/antiox10071103] [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: 06/02/2021] [Revised: 07/02/2021] [Accepted: 07/06/2021] [Indexed: 01/26/2023] Open
Abstract
The NADPH oxidase Nox4 is a hydrogen peroxide (H2O2)-producing enzyme, with the highest expression in the kidney. As the kidney is involved in volume and blood pressure control through sodium handling, we set out to determine the impact of a low sodium diet on these parameters in WT and Nox4-/- mice. Nox4 expression in the murine kidney was restricted to the proximal tubule. Nevertheless, low-sodium-induced weight loss and sodium sparing function was similar in WT and Nox4-/- mice, disputing an important function of renal Nox4 in sodium handling. In contrast, a low sodium diet resulted in a reduction in systolic blood pressure in Nox4-/- as compared to WT mice. This was associated with a selectively lower pressure to heart-rate ratio, as well as heart to body weight ratio. In general, a low sodium diet leads to activation of sympathetic tone and the renin angiotensin system, which subsequently increases peripheral resistance. Our observations suggest that the control by this system is attenuated in Nox4-/- mice, resulting in lower blood pressure in response to low sodium.
Collapse
|
11
|
Xiong L, Feng Y, Hu W, Tan J, Li S, Wang H. Expression of AOX1 Predicts Prognosis of Clear Cell Renal Cell Carcinoma. Front Genet 2021; 12:683173. [PMID: 34290740 PMCID: PMC8287305 DOI: 10.3389/fgene.2021.683173] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 06/08/2021] [Indexed: 01/16/2023] Open
Abstract
Clear cell renal cell carcinoma (ccRCC) is the most prevalent kidney cancer worldwide, and appropriate cancer biomarkers facilitate early diagnosis, treatment, and prognosis prediction in cancer management. However, an accurate biomarker for ccRCC is lacking. This study identified 356 differentially expressed genes in ccRCC tissues compared with normal kidney tissues by integrative analysis of eight ccRCC datasets. Enrichment analysis of the differentially expressed genes unveiled improved adaptation to hypoxia and metabolic reprogramming of the tumor cells. Aldehyde oxidase 1 (AOX1) gene was identified as a biomarker for ccRCC among all the differentially expressed genes. ccRCC tissues expressed significantly lower AOX1 than normal kidney tissues, which was further validated by immunohistochemistry at the protein level and The Cancer Genome Atlas (TCGA) data mining at the mRNA level. Higher AOX1 expression predicted better overall survival in ccRCC patients. Furthermore, AOX1 DNA copy number deletion and hypermethylation were negatively correlated with AOX1 expression, which might be the potential mechanism for its dysregulation in ccRCC. Finally, we illustrated that the effect of AOX1 as a tumor suppressor gene is not restricted to ccRCC but universally exists in many other cancer types. Hence, AOX1 may act as a potential prognostic biomarker and therapeutic target for ccRCC.
Collapse
Affiliation(s)
- Luyang Xiong
- Department of Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuchen Feng
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wei Hu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jiahong Tan
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shusheng Li
- Department of Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hongjie Wang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
12
|
Abstract
Dr Irvine Page proposed the Mosaic Theory of Hypertension in the 1940s advocating that hypertension is the result of many factors that interact to raise blood pressure and cause end-organ damage. Over the years, Dr Page modified his paradigm, and new concepts regarding oxidative stress, inflammation, genetics, sodium homeostasis, and the microbiome have arisen that allow further refinements of the Mosaic Theory. A constant feature of this approach to understanding hypertension is that the various nodes are interdependent and that these almost certainly vary between experimental models and between individuals with hypertension. This review discusses these new concepts and provides an introduction to other reviews in this compendium of Circulation Research.
Collapse
Affiliation(s)
- David G. Harrison
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center
| | - Thomas M. Coffman
- Cardiovascular and Metabolic Disorders Research Program, Duke-National University of Singapore Medical School
| | | |
Collapse
|
13
|
Yang J, Villar VAM, Jose PA, Zeng C. Renal Dopamine Receptors and Oxidative Stress: Role in Hypertension. Antioxid Redox Signal 2021; 34:716-735. [PMID: 32349533 PMCID: PMC7910420 DOI: 10.1089/ars.2020.8106] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Significance: The kidney plays an important role in the long-term control of blood pressure. Oxidative stress is one of the fundamental mechanisms responsible for the development of hypertension. Dopamine, via five subtypes of receptors, plays an important role in the control of blood pressure by various mechanisms, including the inhibition of oxidative stress. Recent Advances: Dopamine receptors exert their regulatory function to decrease the oxidative stress in the kidney and ultimately maintain normal sodium balance and blood pressure homeostasis. An aberration of this regulation may be involved in the pathogenesis of hypertension. Critical Issues: Our present article reviews the important role of oxidative stress and intrarenal dopaminergic system in the regulation of blood pressure, summarizes the current knowledge on renal dopamine receptor-mediated antioxidation, including decreasing reactive oxygen species production, inhibiting pro-oxidant enzyme nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase, and stimulating antioxidative enzymes, and also discusses its underlying mechanisms, including the increased activity of G protein-coupled receptor kinase 4 (GRK4) and abnormal trafficking of renal dopamine receptors in hypertensive status. Future Directions: Identifying the mechanisms of renal dopamine receptors in the regulation of oxidative stress and their contribution to the pathogenesis of hypertension remains an important research focus. Increased understanding of the role of reciprocal regulation between renal dopamine receptors and oxidative stress in the regulation of blood pressure may give us novel insights into the pathogenesis of hypertension and provide a new treatment strategy for hypertension.
Collapse
Affiliation(s)
- Jian Yang
- Department of Clinical Nutrition, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
| | - Van Anthony M Villar
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, USA
| | - Pedro A Jose
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, USA
| | - Chunyu Zeng
- Department of Cardiology, Fujian Heart Medical Center, Fujian Medical University Union Hospital, Fuzhou, People's Republic of China.,Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, People's Republic of China
| |
Collapse
|
14
|
Pisoschi AM, Pop A, Iordache F, Stanca L, Predoi G, Serban AI. Oxidative stress mitigation by antioxidants - An overview on their chemistry and influences on health status. Eur J Med Chem 2020; 209:112891. [PMID: 33032084 DOI: 10.1016/j.ejmech.2020.112891] [Citation(s) in RCA: 249] [Impact Index Per Article: 62.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/30/2020] [Accepted: 09/24/2020] [Indexed: 12/11/2022]
Abstract
The present review paper focuses on the chemistry of oxidative stress mitigation by antioxidants. Oxidative stress is understood as a lack of balance between the pro-oxidant and the antioxidant species. Reactive oxygen species in limited amounts are necessary for cell homeostasis and redox signaling. Excessive reactive oxygenated/nitrogenated species production, which counteracts the organism's defense systems, is known as oxidative stress. Sustained attack of endogenous and exogenous ROS results in conformational and oxidative alterations in key biomolecules. Chronic oxidative stress is associated with oxidative modifications occurring in key biomolecules: lipid peroxidation, protein carbonylation, carbonyl (aldehyde/ketone) adduct formation, nitration, sulfoxidation, DNA impairment such strand breaks or nucleobase oxidation. Oxidative stress is tightly linked to the development of cancer, diabetes, neurodegeneration, cardiovascular diseases, rheumatoid arthritis, kidney disease, eye disease. The deleterious action of reactive oxygenated species and their role in the onset and progression of pathologies are discussed. The results of oxidative attack become themselves sources of oxidative stress, becoming part of a vicious cycle that amplifies oxidative impairment. The term antioxidant refers to a compound that is able to impede or retard oxidation, acting at a lower concentration compared to that of the protected substrate. Antioxidant intervention against the radicalic lipid peroxidation can involve different mechanisms. Chain breaking antioxidants are called primary antioxidants, acting by scavenging radical species, converting them into more stable radicals or non-radical species. Secondary antioxidants quench singlet oxygen, decompose peroxides, chelate prooxidative metal ions, inhibit oxidative enzymes. Moreover, four reactivity-based lines of defense have been identified: preventative antioxidants, radical scavengers, repair antioxidants, and those relying on adaptation mechanisms. The specific mechanism of a series of endogenous and exogenous antioxidants in particular aspects of oxidative stress, is detailed. The final section resumes critical conclusions regarding antioxidant supplementation.
Collapse
Affiliation(s)
- Aurelia Magdalena Pisoschi
- University of Agronomic Sciences and Veterinary Medicine of Bucharest, Faculty of Veterinary Medicine, 105 Splaiul Independentei, 050097, Bucharest, Romania.
| | - Aneta Pop
- University of Agronomic Sciences and Veterinary Medicine of Bucharest, Faculty of Veterinary Medicine, 105 Splaiul Independentei, 050097, Bucharest, Romania
| | - Florin Iordache
- University of Agronomic Sciences and Veterinary Medicine of Bucharest, Faculty of Veterinary Medicine, 105 Splaiul Independentei, 050097, Bucharest, Romania
| | - Loredana Stanca
- University of Agronomic Sciences and Veterinary Medicine of Bucharest, Faculty of Veterinary Medicine, 105 Splaiul Independentei, 050097, Bucharest, Romania
| | - Gabriel Predoi
- University of Agronomic Sciences and Veterinary Medicine of Bucharest, Faculty of Veterinary Medicine, 105 Splaiul Independentei, 050097, Bucharest, Romania
| | - Andreea Iren Serban
- University of Agronomic Sciences and Veterinary Medicine of Bucharest, Faculty of Veterinary Medicine, 105 Splaiul Independentei, 050097, Bucharest, Romania
| |
Collapse
|
15
|
Leipziger J, Praetorius H. Renal Autocrine and Paracrine Signaling: A Story of Self-protection. Physiol Rev 2020; 100:1229-1289. [PMID: 31999508 DOI: 10.1152/physrev.00014.2019] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Autocrine and paracrine signaling in the kidney adds an extra level of diversity and complexity to renal physiology. The extensive scientific production on the topic precludes easy understanding of the fundamental purpose of the vast number of molecules and systems that influence the renal function. This systematic review provides the broader pen strokes for a collected image of renal paracrine signaling. First, we recapitulate the essence of each paracrine system one by one. Thereafter the single components are merged into an overarching physiological concept. The presented survey shows that despite the diversity in the web of paracrine factors, the collected effect on renal function may not be complicated after all. In essence, paracrine activation provides an intelligent system that perceives minor perturbations and reacts with a coordinated and integrated tissue response that relieves the work load from the renal epithelia and favors diuresis and natriuresis. We suggest that the overall function of paracrine signaling is reno-protection and argue that renal paracrine signaling and self-regulation are two sides of the same coin. Thus local paracrine signaling is an intrinsic function of the kidney, and the overall renal effect of changes in blood pressure, volume load, and systemic hormones will always be tinted by its paracrine status.
Collapse
Affiliation(s)
- Jens Leipziger
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; and Aarhus Institute of Advanced Studies (AIAS), Aarhus University, Aarhus, Denmark
| | - Helle Praetorius
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; and Aarhus Institute of Advanced Studies (AIAS), Aarhus University, Aarhus, Denmark
| |
Collapse
|
16
|
Yang N, Gonzalez-Vicente A, Garvin JL. Angiotensin II-induced superoxide and decreased glutathione in proximal tubules: effect of dietary fructose. Am J Physiol Renal Physiol 2019; 318:F183-F192. [PMID: 31760771 DOI: 10.1152/ajprenal.00462.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Angiotensin II exacerbates oxidative stress in part by increasing superoxide (O2-) production by many renal tissues. However, whether it does so in proximal tubules and the source of O2- in this segment are unknown. Dietary fructose enhances the stimulatory effect of angiotensin II on proximal tubule Na+ reabsorption, but whether this is true for oxidative stress is unknown. We hypothesized that angiotensin II causes proximal nephron oxidative stress in part by stimulating NADPH oxidase (NOX)4-dependent O2- production and decreasing the amount of the antioxidant glutathione, and this is exacerbated by dietary fructose. We measured basal and angiotensin II-stimulated O2- production with and without inhibitors, NOX1 and NOX4 expression, and total and reduced glutathione (GSH) in proximal tubules from rats drinking either tap water (control) or 20% fructose. Angiotensin II (10 nM) increased O2- production by 113 ± 42 relative light units·mg protein-1·s-1 in controls and 401 ± 74 relative light units·mg protein-1·s-1 with 20% fructose (n = 11 for each group, P < 0.05 vs. control). Apocynin and the Nox1/4 inhibitor GKT136901 prevented angiotensin II-induced increases in both groups. NOX4 expression was not different between groups. NOX1 expression was undetectable. Angiotensin II decreased GSH by 1.8 ± 0.8 nmol/mg protein in controls and by 4.2 ± 0.9 nmol/mg protein with 20% fructose (n = 18 for each group, P < 0.047 vs. control). We conclude that 1) angiotensin II causes oxidative stress in proximal tubules by increasing O2- production by NOX4 and decreasing GSH and 2) dietary fructose enhances the ability of angiotensin II to stimulate O2- and diminish GSH, thereby exacerbating oxidative stress in this segment.
Collapse
Affiliation(s)
- Nianxin Yang
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Agustin Gonzalez-Vicente
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Jeffrey L Garvin
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| |
Collapse
|
17
|
Gonzalez-Vicente A, Hong N, Garvin JL. Effects of reactive oxygen species on renal tubular transport. Am J Physiol Renal Physiol 2019; 317:F444-F455. [PMID: 31215804 DOI: 10.1152/ajprenal.00604.2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Reactive oxygen species (ROS) play a critical role in regulating nephron transport both via transcellular and paracellular pathways under physiological and pathological circumstances. Here, we review the progress made in the past ~10 yr in understanding how ROS regulate solute and water transport in individual nephron segments. Our knowledge in this field is still rudimentary, with basic information lacking. This is most obvious when looking at the reported disparate effects of superoxide ([Formula: see text]) and H2O2 on proximal nephron transport, where there are no easy explanations as to how to reconcile the data. Similarly, we know almost nothing about the regulation of transport in thin descending and ascending limbs, information that is likely critical to understanding the urine concentrating mechanism. In the thick ascending limb, there is general agreement that ROS enhance transcellular reabsorption of NaCl, but we know very little about their effects on the paracellular pathway and therefore Ca2+ and Mg2+ transport. In the distal convoluted tubule, precious little is known. In the collecting duct, there is general agreement that ROS stimulate the epithelial Na+ channel.
Collapse
Affiliation(s)
- Agustin Gonzalez-Vicente
- Department of Inflammation and Immunity, Cleveland Clinic, Lerner Research Institute, Cleveland, Ohio
| | - Nancy Hong
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University Cleveland, Ohio
| | - Jeffrey L Garvin
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University Cleveland, Ohio
| |
Collapse
|
18
|
Bashir SO. Concomitant administration of resveratrol and insulin protects against diabetes mellitus type-1-induced renal damage and impaired function via an antioxidant-mediated mechanism and up-regulation of Na +/K +-ATPase. Arch Physiol Biochem 2019; 125:104-113. [PMID: 29436859 DOI: 10.1080/13813455.2018.1437752] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This study investigated if a combination of resveratrol (RES) and insulin could reverse type 1 diabetic mellitus-induced (T1DM) nephropathy and illustrates mechanism of action. Rats were divided into six groups (n = 10/group) as follows: control, control + RES (20 mg/kg), T1DM, T1DM + RES, T1DM + insulin (1 U/g), and T1DM + RES + insulin and treated for eight weeks. While individual administrations of both drugs significantly but partially restored renal function and cortex architectures, combination therapy of both RES and insulin produced the maximum improvements. Mechanism of actions revealed a synergist effect of both drugs due to hypoglycaemic effect of insulin and the ability of both drugs to increase renal cortex antioxidant enzymes activities, inhibit lipid peroxidation, and up-regulate Na+/K+-ATPase, independent of each others. In conclusion, these data suggest the combined therapy with insulin and RES could provide an excellent combined drug therapy against T1DM-induced nephropathy.
Collapse
Affiliation(s)
- Salah O Bashir
- a Department of Physiology, College of Medicine , King Khalid University , Abha , Saudi Arabia
| |
Collapse
|
19
|
Jönsson S, Becirovic-Agic M, Isackson H, Tveitarås MK, Skogstrand T, Narfström F, Karlsen TV, Lidén Å, Leh S, Ericsson M, Nilsson SK, Reed RK, Hultström M. Angiotensin II and salt-induced decompensation in Balb/CJ mice is aggravated by fluid retention related to low oxidative stress. Am J Physiol Renal Physiol 2019; 316:F914-F933. [PMID: 30785350 DOI: 10.1152/ajprenal.00483.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Balb/CJ mice are more sensitive to treatment with angiotensin II (ANG II) and high-salt diet compared with C57BL/6J mice. Together with higher mortality, they develop edema, signs of heart failure, and acute kidney injury. The aim of the present study was to identify differences in renal gene regulation that may affect kidney function and fluid balance, which could contribute to decompensation in Balb/CJ mice after ANG II + salt treatment. Male Balb/CJ and C57BL/6J mice were divided into the following five different treatment groups: control, ANG II, salt, ANG II + salt, and ANG II + salt + N-acetylcysteine. Gene expression microarrays were used to explore differential gene expression after treatment and between the strains. Published data from the Mouse Genome Database were used to identify the associated genomic differences. The glomerular filtration rate (GFR) was measured using inulin clearance, and fluid balance was measured using metabolic cages. Gene ontology enrichment analysis of gene expression microarrays identified glutathione transferase (antioxidant system) as highly enriched among differentially expressed genes. Balb/CJ mice had similar GFR compared with C57BL/6J mice but excreted less Na+ and water, although net fluid and electrolyte balance did not differ, suggesting that Balb/CJ mice may be inherently more prone to decompensation. Interestingly, C57BL/6J mice had higher urinary oxidative stress despite their relative protection from decompensation. In addition, treatment with the antioxidant N-acetylcysteine decreased oxidative stress in C57BL/6J mice, reduced urine excretion, and increased mortality. Balb/CJ mice are more sensitive than C57BL/6J to ANG II + salt, in part mediated by lower oxidative stress, which favors fluid and Na+ retention.
Collapse
Affiliation(s)
- Sofia Jönsson
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Mediha Becirovic-Agic
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Henrik Isackson
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.,Department of Medical Sciences, Cardiology, Uppsala University , Uppsala , Sweden
| | | | | | - Fredrik Narfström
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Tine V Karlsen
- Department of Biomedicine, University of Bergen , Norway
| | - Åsa Lidén
- Department of Biomedicine, University of Bergen , Norway
| | - Sabine Leh
- Department of Pathology, Haukeland University Hospital , Bergen , Norway.,Department of Clinical Medicine, University of Bergen , Norway
| | | | - Stefan K Nilsson
- Department of Medical Biosciences, Umeå University , Umeå , Sweden
| | - Rolf K Reed
- Department of Biomedicine, University of Bergen , Norway.,Centre for Cancer Biomarkers (CCBIO), University of Bergen , Norway
| | - Michael Hultström
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.,Department of Biomedicine, University of Bergen , Norway.,Anesthesia and Intensive Care, Department of Surgical Sciences, Uppsala University , Uppsala , Sweden
| |
Collapse
|
20
|
Cuevas S, Villar VAM, Jose PA. Genetic polymorphisms associated with reactive oxygen species and blood pressure regulation. THE PHARMACOGENOMICS JOURNAL 2019; 19:315-336. [PMID: 30723314 PMCID: PMC6650341 DOI: 10.1038/s41397-019-0082-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 10/19/2018] [Accepted: 12/21/2018] [Indexed: 02/08/2023]
Abstract
Hypertension is the most prevalent cause of cardiovascular disease and kidney failure, but only about 50% of patients achieve adequate blood pressure control, in part, due to inter-individual genetic variations in the response to antihypertensive medication. Significant strides have been made toward the understanding of the role of reactive oxygen species (ROS) in the regulation of the cardiovascular system. However, the role of ROS in human hypertension is still unclear. Polymorphisms of some genes involved in the regulation of ROS production are associated with hypertension, suggesting their potential influence on blood pressure control and response to antihypertensive medication. This review provides an update on the genes associated with the regulation of ROS production in hypertension and discusses the controversies on the use of antioxidants in the treatment of hypertension, including the antioxidant effects of antihypertensive drugs.
Collapse
Affiliation(s)
- Santiago Cuevas
- Center for Translational Science, Children's National Health System, 111 Michigan Avenue, NW, Washington, DC, 20010, USA.
| | - Van Anthony M Villar
- Department of Medicine, Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, Walter G. Ross Hall, Suite 738, 2300 I Street, NW, Washington, DC, 20052, USA
| | - Pedro A Jose
- Department of Medicine, Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, Walter G. Ross Hall, Suite 738, 2300 I Street, NW, Washington, DC, 20052, USA
| |
Collapse
|
21
|
Abdulmahdi W, Rabadi MM, Jules E, Marghani Y, Marji N, Leung J, Zhang F, Siani A, Siskind T, Vedovino K, Chowdhury N, Sekulic M, Ratliff BB. Kidney dysfunction in the low-birth weight murine adult: implications of oxidative stress. Am J Physiol Renal Physiol 2018; 315:F583-F594. [DOI: 10.1152/ajprenal.00164.2018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Maternal undernutrition (MUN) during pregnancy leads to low-birth weight (LBW) neonates that have a reduced kidney nephron endowment and higher morbidity as adults. Using a severe combined caloric and protein-restricted mouse model of MUN to generate LBW mice, we examined the progression of renal insufficiency in LBW adults. Through 6 mo of age, LBW males experienced greater albuminuria (ELISA analysis), a more rapid onset of glomerular hypertrophy, and a worse survival rate than LBW females. In contrast, both sexes experienced a comparable progressive decline in renal vascular density (immunofluorescence analysis), renal blood flow (Laser-Doppler flowmetry analysis), glomerular filtration rate (FITC-sinistrin clearance analysis), and a progressive increase in systemic blood pressure (measured via tail-cuff method). Isolated aortas from both LBW sexes demonstrated reduced vasodilation in response to ACh, indicative of reduced nitric oxide bioavailability and endothelial dysfunction. ELISA and immunofluorescence analysis revealed a significant increase of circulating reactive oxygen species and NADPH oxidase type 4 (NOX4) expression in both LBW sexes, although these increases were more pronounced in males. Although more effective in males, chronic tempol treatment did improve all observed pathologies in both sexes of LBW mice. Chronic NOX4 inhibition with GKT137831 was more effective than tempol in preventing pathologies in LBW males. In conclusion, despite some minor differences, LBW female and male adults have a reduced nephron endowment comparable with progressive renal and vascular dysfunction, which is associated with increased oxidative stress and subsequent endothelial dysfunction. Tempol treatment and/or NOX4 inhibition attenuates renal and vascular dysfunction in LBW adults.
Collapse
Affiliation(s)
- Wasan Abdulmahdi
- Department of Physiology, Renal Research Institute, New York Medical College, Valhalla, New York
| | - May M. Rabadi
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Edson Jules
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Yara Marghani
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Noor Marji
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Jessica Leung
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Frank Zhang
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Avi Siani
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Tamar Siskind
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Kiara Vedovino
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Nazrul Chowdhury
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
| | - Miroslav Sekulic
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Brian B. Ratliff
- Department of Medicine, Renal Research Institute, New York Medical College, Valhalla, New York
- Department of Physiology, Renal Research Institute, New York Medical College, Valhalla, New York
| |
Collapse
|
22
|
Saleh MA, De Miguel C, Stevens DI, Carmines PK, Pollock DM, Pollock JS. Free radical scavenging decreases endothelin-1 excretion and glomerular albumin permeability during type 1 diabetes. Physiol Rep 2017; 4:4/24/e13055. [PMID: 28039404 PMCID: PMC5210388 DOI: 10.14814/phy2.13055] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 11/03/2016] [Accepted: 11/04/2016] [Indexed: 11/24/2022] Open
Abstract
Increased renal endothelin-1 (ET-1) production and an ETA receptor-dependent increase in glomerular albumin permeability (Palb) accompany type 1 diabetes mellitus (T1D). We hypothesized that T1D-induced oxidative stress contributes to renal ET-1 production and glomerular Palb Male rats with streptozotocin-induced T1D were provided free access to drinking water without additives (T1D rats) or containing the free radical scavenger tempol (1 mmol/L; T1D+Tempol). After 3 weeks, T1D+Tempol rats displayed lower urinary excretion of thiobarbituric acid reactive substances and glomerular superoxide production (dihydroethidium staining) compared to T1D rats. Urinary ET-1 excretion and inner medullary (but not cortical or outer medullary) prepro-ET-1 mRNA expression were lower in the T1D+Tempol group than in the T1D group. Palb, measured as the change in volume of isolated glomeruli upon exposure to oncotic gradients of albumin, was significantly lower in the T1D+Tempol group than in the T1D group. Tempol treatment did not alter protein excretion or creatinine clearance. These data support the postulate that oxidative stress contributes to glomerular Palb and renal ET-1 production during the early phase of type 1 diabetes.
Collapse
Affiliation(s)
- Mohamed A Saleh
- Medical College of Georgia, Augusta University, Augusta, Georgia.,Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Carmen De Miguel
- Cardio-Renal Physiology & Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - David I Stevens
- Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Pamela K Carmines
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
| | - David M Pollock
- Cardio-Renal Physiology & Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Jennifer S Pollock
- Cardio-Renal Physiology & Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama .,Medical College of Georgia, Augusta University, Augusta, Georgia
| |
Collapse
|
23
|
Gonzalez-Vicente A, Garvin JL. Effects of Reactive Oxygen Species on Tubular Transport along the Nephron. Antioxidants (Basel) 2017; 6:antiox6020023. [PMID: 28333068 PMCID: PMC5488003 DOI: 10.3390/antiox6020023] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/15/2017] [Accepted: 03/18/2017] [Indexed: 12/17/2022] Open
Abstract
Reactive oxygen species (ROS) are oxygen-containing molecules naturally occurring in both inorganic and biological chemical systems. Due to their high reactivity and potentially damaging effects to biomolecules, cells express a battery of enzymes to rapidly metabolize them to innocuous intermediaries. Initially, ROS were considered by biologists as dangerous byproducts of respiration capable of causing oxidative stress, a condition in which overproduction of ROS leads to a reduction in protective molecules and enzymes and consequent damage to lipids, proteins, and DNA. In fact, ROS are used by immune systems to kill virus and bacteria, causing inflammation and local tissue damage. Today, we know that the functions of ROS are not so limited, and that they also act as signaling molecules mediating processes as diverse as gene expression, mechanosensation, and epithelial transport. In the kidney, ROS such as nitric oxide (NO), superoxide (O₂-), and their derivative molecules hydrogen peroxide (H₂O₂) and peroxynitrite (ONO₂-) regulate solute and water reabsorption, which is vital to maintain electrolyte homeostasis and extracellular fluid volume. This article reviews the effects of NO, O₂-, ONO₂-, and H₂O₂ on water and electrolyte reabsorption in proximal tubules, thick ascending limbs, and collecting ducts, and the effects of NO and O₂- in the macula densa on tubuloglomerular feedback.
Collapse
Affiliation(s)
- Agustin Gonzalez-Vicente
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
- Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires C1113AAD, Argentina.
| | - Jeffrey L Garvin
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
| |
Collapse
|
24
|
Liu J, Yan Y, Nie Y, Shapiro JI. Na/K-ATPase Signaling and Salt Sensitivity: The Role of Oxidative Stress. Antioxidants (Basel) 2017; 6:E18. [PMID: 28257114 PMCID: PMC5384181 DOI: 10.3390/antiox6010018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 02/10/2017] [Accepted: 02/22/2017] [Indexed: 02/07/2023] Open
Abstract
Other than genetic regulation of salt sensitivity of blood pressure, many factors have been shown to regulate renal sodium handling which contributes to long-term blood pressure regulation and have been extensively reviewed. Here we present our progress on the Na/K-ATPase signaling mediated sodium reabsorption in renal proximal tubules, from cardiotonic steroids-mediated to reactive oxygen species (ROS)-mediated Na/K-ATPase signaling that contributes to experimental salt sensitivity.
Collapse
Affiliation(s)
- Jiang Liu
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA.
| | - Yanling Yan
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA.
| | - Ying Nie
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA.
| | - Joseph I Shapiro
- Department of Medicine, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25701, USA
| |
Collapse
|
25
|
Yan Y, Shapiro AP, Mopidevi BR, Chaudhry MA, Maxwell K, Haller ST, Drummond CA, Kennedy DJ, Tian J, Malhotra D, Xie ZJ, Shapiro JI, Liu J. Protein Carbonylation of an Amino Acid Residue of the Na/K-ATPase α1 Subunit Determines Na/K-ATPase Signaling and Sodium Transport in Renal Proximal Tubular Cells. J Am Heart Assoc 2016; 5:e003675. [PMID: 27613772 PMCID: PMC5079028 DOI: 10.1161/jaha.116.003675] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 08/12/2016] [Indexed: 01/12/2023]
Abstract
BACKGROUND We have demonstrated that cardiotonic steroids, such as ouabain, signaling through the Na/K-ATPase, regulate sodium reabsorption in the renal proximal tubule. By direct carbonylation modification of the Pro222 residue in the actuator (A) domain of pig Na/K-ATPase α1 subunit, reactive oxygen species are required for ouabain-stimulated Na/K-ATPase/c-Src signaling and subsequent regulation of active transepithelial (22)Na(+) transport. In the present study we sought to determine the functional role of Pro222 carbonylation in Na/K-ATPase signaling and sodium handling. METHODS AND RESULTS Stable pig α1 knockdown LLC-PK1-originated PY-17 cells were rescued by expressing wild-type rat α1 and rat α1 with a single mutation of Pro224 (corresponding to pig Pro222) to Ala. This mutation does not affect ouabain-induced inhibition of Na/K-ATPase activity, but abolishes the effects of ouabain on Na/K-ATPase/c-Src signaling, protein carbonylation, Na/K-ATPase endocytosis, and active transepithelial (22)Na(+) transport. CONCLUSIONS Direct carbonylation modification of Pro224 in the rat α1 subunit determines ouabain-mediated Na/K-ATPase signal transduction and subsequent regulation of renal proximal tubule sodium transport.
Collapse
Affiliation(s)
- Yanling Yan
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV
| | - Anna P Shapiro
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Brahma R Mopidevi
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Muhammad A Chaudhry
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV
| | - Kyle Maxwell
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV
| | - Steven T Haller
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | | | - David J Kennedy
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Jiang Tian
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Deepak Malhotra
- Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Zi-Jian Xie
- Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV
| | - Joseph I Shapiro
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV Department of Medicine, University of Toledo College of Medicine, Toledo, OH
| | - Jiang Liu
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine, Marshall University, Huntington, WV Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV
| |
Collapse
|
26
|
Jia Z, Zhuang Y, Hu C, Zhang X, Ding G, Zhang Y, Rohatgi R, Hua H, Huang S, He JCJ, Zhang A. Albuminuria enhances NHE3 and NCC via stimulation of mitochondrial oxidative stress/angiotensin II axis. Oncotarget 2016; 7:47134-47144. [PMID: 27323402 PMCID: PMC5216930 DOI: 10.18632/oncotarget.9972] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 05/20/2016] [Indexed: 12/31/2022] Open
Abstract
Imbalance of salt and water is a frequent and challenging complication of kidney disease, whose pathogenic mechanisms remain elusive. Employing an albumin overload mouse model, we discovered that albuminuria enhanced the expression of NHE3 and NCC but not other transporters in murine kidney in line with the stimulation of angiotensinogen (AGT)/angiotensin converting enzyme (ACE)/angiotensin (Ang) II cascade. In primary cultures of renal tubular cells, albumin directly stimulated AGT/ACE/Ang II and upregulated NHE3 and NCC expression. Blocking Ang II production with an ACE inhibitor normalized the upregulation of NHE3 and NCC in cells. Interestingly, albumin overload significantly reduced mitochondrial superoxide dismutase (SOD2), and administration of a SOD2 mimic (MnTBAP) normalized the expression of NHE3, NCC, and the components of AGT/ACE pathway affected by albuminuria, indicating a key role of mitochondria-derived oxidative stress in modulating renin-angiotensin system (RAS) and renal sodium transporters. In addition, the functional data showing the reduced urinary excretion of Na and Cl and enhanced response to specific NCC inhibitor further supported the regulatory results of sodium transporters following albumin overload. More importantly, the upregulation of NHE3 and NCC and activation of ACE/Ang II signaling pathway were also observed in albuminuric patient kidneys, suggesting that our animal model accurately replicates the human condition. Taken together, these novel findings demonstrated that albuminuria is of importance in resetting renal salt handling via mitochondrial oxidative stress-initiated stimulation of ACE/Ang II cascade. This may also offer novel, effective therapeutic targets for dealing with salt and water imbalance in proteinuric renal diseases.
Collapse
Affiliation(s)
- Zhanjun Jia
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Yibo Zhuang
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Caiyu Hu
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Xintong Zhang
- The First Clinical Medical College of Nanjing Medical University, Nanjing, China
| | - Guixia Ding
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Yue Zhang
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Rajeev Rohatgi
- Department of Medicine, Mount Sinai School of Medicine, New York, New York, USA
| | - Hu Hua
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Songming Huang
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - John Ci-jiang He
- Division of Nephrology, Department of Medicine, Mount Sinai School of Medicine, New York, New York, USA
| | - Aihua Zhang
- Department of Nephrology, Nanjing Children's Hospital, Affiliated with Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| |
Collapse
|
27
|
Tamma G, Valenti G. Evaluating the Oxidative Stress in Renal Diseases: What Is the Role for S-Glutathionylation? Antioxid Redox Signal 2016; 25:147-64. [PMID: 26972776 DOI: 10.1089/ars.2016.6656] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE Reactive oxygen species (ROS) have long been considered as toxic derivatives of aerobic metabolism displaying a harmful effect to living cells. Deregulation of redox homeostasis and production of excessive free radicals may contribute to the pathogenesis of kidney diseases. In line, oxidative stress increases in patients with renal dysfunctions due to a general increase of ROS paralleled by impaired antioxidant ability. RECENT ADVANCES Emerging evidence revealed that physiologically, ROS can act as signaling molecules interplaying with several transduction pathways such as proliferation, differentiation, and apoptosis. ROS can exert signaling functions by modulating, at different layers, protein oxidation since proteins have "cysteine switches" that can be reversibly reduced or oxidized, supporting the dynamic signaling regulation function. In this scenario, S-glutathionylation is a posttranslational modification involved in oxidative cellular response. CRITICAL ISSUES Although it is widely accepted that renal dysfunctions are often associated with altered redox signaling, the relative role of S-glutathionylation on the pathogenesis of specific renal diseases remains unclear and needs further investigations. In this review, we discuss the impact of ROS in renal health and diseases and the role of selective S-glutathionylation proteins potentially relevant to renal physiology. FUTURE DIRECTIONS The paucity of studies linking the reversible protein glutathionylation with specific renal disorders remains unmet. The growing number of S-glutathionylated proteins indicates that this is a fascinating area of research. In this respect, further studies on the association of reversible glutathionylation with renal diseases, characterized by oxidative stress, may be useful to develop new pharmacological molecules targeting protein S-glutathionylation. Antioxid. Redox Signal. 25, 147-164.
Collapse
Affiliation(s)
- Grazia Tamma
- 1 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari , Bari, Italy .,2 Istituto Nazionale di Biostrutture e Biosistemi (I.N.B.B.) , Rome, Italy
| | - Giovanna Valenti
- 1 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari , Bari, Italy .,2 Istituto Nazionale di Biostrutture e Biosistemi (I.N.B.B.) , Rome, Italy .,3 Centro di Eccellenza di Genomica in campo Biomedico ed Agrario (CEGBA) , Bari, Italy
| |
Collapse
|
28
|
Abstract
SIGNIFICANCE A common link between all forms of acute and chronic kidney injuries, regardless of species, is enhanced generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) during injury/disease progression. While low levels of ROS and RNS are required for prosurvival signaling, cell proliferation and growth, and vasoreactivity regulation, an imbalance of ROS and RNS generation and elimination leads to inflammation, cell death, tissue damage, and disease/injury progression. RECENT ADVANCES Many aspects of renal oxidative stress still require investigation, including clarification of the mechanisms which prompt ROS/RNS generation and subsequent renal damage. However, we currently have a basic understanding of the major features of oxidative stress pathology and its link to kidney injury/disease, which this review summarizes. CRITICAL ISSUES The review summarizes the critical sources of oxidative stress in the kidney during injury/disease, including generation of ROS and RNS from mitochondria, NADPH oxidase, and inducible nitric oxide synthase. The review next summarizes the renal antioxidant systems that protect against oxidative stress, including superoxide dismutase and catalase, the glutathione and thioredoxin systems, and others. Next, we describe how oxidative stress affects kidney function and promotes damage in every nephron segment, including the renal vessels, glomeruli, and tubules. FUTURE DIRECTIONS Despite the limited success associated with the application of antioxidants for treatment of kidney injury/disease thus far, preventing the generation and accumulation of ROS and RNS provides an ideal target for potential therapeutic treatments. The review discusses the shortcomings of antioxidant treatments previously used and the potential promise of new ones. Antioxid. Redox Signal. 25, 119-146.
Collapse
Affiliation(s)
- Brian B Ratliff
- 1 Department of Medicine, Renal Research Institute , New York Medical College, Valhalla, New York.,2 Department of Physiology, Renal Research Institute , New York Medical College, Valhalla, New York
| | - Wasan Abdulmahdi
- 2 Department of Physiology, Renal Research Institute , New York Medical College, Valhalla, New York
| | - Rahul Pawar
- 1 Department of Medicine, Renal Research Institute , New York Medical College, Valhalla, New York
| | - Michael S Wolin
- 2 Department of Physiology, Renal Research Institute , New York Medical College, Valhalla, New York
| |
Collapse
|
29
|
Shah PT, Martin R, Yan Y, Shapiro JI, Liu J. Carbonylation Modification Regulates Na/K-ATPase Signaling and Salt Sensitivity: A Review and a Hypothesis. Front Physiol 2016; 7:256. [PMID: 27445847 PMCID: PMC4923243 DOI: 10.3389/fphys.2016.00256] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 06/11/2016] [Indexed: 01/01/2023] Open
Abstract
Na/K-ATPase signaling has been implicated in different physiological and pathophysiological conditions. Accumulating evidence indicates that oxidative stress not only regulates the Na/K-ATPase enzymatic activity, but also regulates its signaling and other functions. While cardiotonic steroids (CTS)-induced increase in reactive oxygen species (ROS) generation is an intermediate step in CTS-mediated Na/K-ATPase signaling, increase in ROS alone also stimulates Na/K-ATPase signaling. Based on literature and our observations, we hypothesize that ROS have biphasic effects on Na/K-ATPase signaling, transcellular sodium transport, and urinary sodium excretion. Oxidative modulation, in particular site specific carbonylation of the Na/K-ATPase α1 subunit, is a critical step in proximal tubular Na/K-ATPase signaling and decreased transcellular sodium transport leading to increases in urinary sodium excretion. However, once this system is overstimulated, the signaling, and associated changes in sodium excretion are blunted. This review aims to evaluate ROS-mediated carbonylation of the Na/K-ATPase, and its potential role in the regulation of pump signaling and sodium reabsorption in the renal proximal tubule (RPT).
Collapse
Affiliation(s)
- Preeya T Shah
- Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University Huntington, WV, USA
| | - Rebecca Martin
- Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University Huntington, WV, USA
| | - Yanling Yan
- Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University Huntington, WV, USA
| | - Joseph I Shapiro
- Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University Huntington, WV, USA
| | - Jiang Liu
- Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University Huntington, WV, USA
| |
Collapse
|
30
|
Fu Q, Colgan SP, Shelley CS. Hypoxia: The Force that Drives Chronic Kidney Disease. Clin Med Res 2016; 14:15-39. [PMID: 26847481 PMCID: PMC4851450 DOI: 10.3121/cmr.2015.1282] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 09/30/2015] [Indexed: 12/15/2022]
Abstract
In the United States the prevalence of end-stage renal disease (ESRD) reached epidemic proportions in 2012 with over 600,000 patients being treated. The rates of ESRD among the elderly are disproportionally high. Consequently, as life expectancy increases and the baby-boom generation reaches retirement age, the already heavy burden imposed by ESRD on the US health care system is set to increase dramatically. ESRD represents the terminal stage of chronic kidney disease (CKD). A large body of evidence indicating that CKD is driven by renal tissue hypoxia has led to the development of therapeutic strategies that increase kidney oxygenation and the contention that chronic hypoxia is the final common pathway to end-stage renal failure. Numerous studies have demonstrated that one of the most potent means by which hypoxic conditions within the kidney produce CKD is by inducing a sustained inflammatory attack by infiltrating leukocytes. Indispensable to this attack is the acquisition by leukocytes of an adhesive phenotype. It was thought that this process resulted exclusively from leukocytes responding to cytokines released from ischemic renal endothelium. However, recently it has been demonstrated that leukocytes also become activated independent of the hypoxic response of endothelial cells. It was found that this endothelium-independent mechanism involves leukocytes directly sensing hypoxia and responding by transcriptional induction of the genes that encode the β2-integrin family of adhesion molecules. This induction likely maintains the long-term inflammation by which hypoxia drives the pathogenesis of CKD. Consequently, targeting these transcriptional mechanisms would appear to represent a promising new therapeutic strategy.
Collapse
Affiliation(s)
- Qiangwei Fu
- Kabara Cancer Research Institute, La Crosse, WI
| | - Sean P Colgan
- Mucosal Inflammation Program and University of Colorado School of Medicine, Aurora, CO
| | - Carl Simon Shelley
- University of Wisconsin School of Medicine and Public Health, Madison, WI
| |
Collapse
|
31
|
Damiano S, Ciarcia R, Montagnaro S, Pagnini U, Garofano T, Capasso G, Florio S, Giordano A. Prevention of nephrotoxicity induced by cyclosporine-A: role of antioxidants. J Cell Biochem 2015; 116:364-9. [PMID: 25418335 DOI: 10.1002/jcb.25022] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 11/18/2014] [Indexed: 11/10/2022]
Abstract
Cyclosporine A (CsA) is a powerful immunosuppressive drug used to prevent allograft rejection after organ transplantation as well as in human and veterinary medicine. Unfortunately, its use is hampered by its nephrotoxic effects. The mechanisms of CsA-induced hypertension and nephrotoxicity are not clear, but several studies suggest the possible involvement of free radicals. In this review we have summarized the effect of some antioxidants that we have used in the recent years, in combination with CsA, to better understand the exact mechanism of action of CsA and to try to open new perspectives in the treatment of CsA nephrotoxicity.
Collapse
Affiliation(s)
- Sara Damiano
- Department of Veterinary Medicine and Animal Productions, University of Naples "Federico II", 80137, Naples, Italy
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Ciarcia R, Damiano S, Florio A, Spagnuolo M, Zacchia E, Squillacioti C, Mirabella N, Florio S, Pagnini U, Garofano T, Polito MS, Capasso G, Giordano A. The Protective Effect of Apocynin on Cyclosporine A-Induced Hypertension and Nephrotoxicity in Rats. J Cell Biochem 2015; 116:1848-1856. [DOI: 10.1002/jcb.25140] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Affiliation(s)
- Roberto Ciarcia
- Department of Veterinary Medicine and Animal Productions; University of Naples “Federico II,”; Naples 80137 Italy
| | - Sara Damiano
- Department of Veterinary Medicine and Animal Productions; University of Naples “Federico II,”; Naples 80137 Italy
| | - Alessia Florio
- Department of Veterinary Medicine and Animal Productions; University of Naples “Federico II,”; Naples 80137 Italy
| | | | - Enza Zacchia
- Department of Nephrology; Second University of Naples; Naples Italy
| | - Caterina Squillacioti
- Department of Veterinary Medicine and Animal Productions; University of Naples “Federico II,”; Naples 80137 Italy
| | - Nicola Mirabella
- Department of Veterinary Medicine and Animal Productions; University of Naples “Federico II,”; Naples 80137 Italy
| | - Salvatore Florio
- Department of Veterinary Medicine and Animal Productions; University of Naples “Federico II,”; Naples 80137 Italy
| | - Ugo Pagnini
- Department of Veterinary Medicine and Animal Productions; University of Naples “Federico II,”; Naples 80137 Italy
| | | | - Maria Sole Polito
- Department of Medicine, Surgery and Neuroscience; University of Siena; Siena Italy
| | | | - Antonio Giordano
- Department of Medicine, Surgery and Neuroscience; University of Siena; Siena Italy
- Sbarro Institute for Cancer Research and Molecular Medicine; Center of Biotechnology; College of Science and Technology; Temple University; Philadelphia Pennsylvania
| |
Collapse
|
33
|
Li L, Feng D, Luo Z, Welch WJ, Wilcox CS, Lai EY. Remodeling of Afferent Arterioles From Mice With Oxidative Stress Does Not Account for Increased Contractility but Does Limit Excessive Wall Stress. Hypertension 2015; 66:550-6. [PMID: 26101341 DOI: 10.1161/hypertensionaha.115.05631] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Accepted: 05/27/2015] [Indexed: 11/16/2022]
Abstract
Because superoxide dismutase (SOD) knockout enhances arteriolar remodeling and contractility, we hypothesized that remodeling enhances contractility. In the isolated and perfused renal afferent arterioles from SOD wild type (+/+) and gene-deleted mice, contractility was assessed from reductions in luminal diameter with perfusion pressure from 40 to 80 mm Hg (myogenic responses) or angiotensin II (10(-6) mol/L), remodeling from media:lumen area ratio, superoxide (O2 (·-)) and hydrogen peroxide (H2O2) from fluorescence microscopy, and wall stress from wall tension/wall thickness. Compared with +/+ strains, arterioles from SOD1-/-, SOD2+/-, and SOD3-/- mice developed significantly (P<0.05) more O2 (·-) with perfusion pressure and angiotensin II and significantly increased myogenic responses (SOD1-/-: -20.7±2.2% versus -12.7±1.6%; SOD2+/-: -7.4±1.3% versus -12.6±1.4%; and SOD3-/-: -9.1±1.9% versus -15.8±2.2%) and angiotensin II contractions and ≈2-fold increased media:lumen ratios. Media:lumen ratios correlated with myogenic responses (r(2) =0.23; P<0.01), angiotensin II contractions (r(2)=0.57; P<0.0001), and active wall tension (r(2) =0.19; P<0.01), but not with active wall stress (r(2)=0.08; NS). Differences in myogenic responses among SOD3 mice were abolished by bath addition of SOD and were increased 3 days after inducing SOD3 knockout (-26.9±1.7% versus -20.1±0.7%; P<0.05), despite unchanged media:lumen ratios (2.01±0.09 versus 2.02±0.03; NS). We conclude that cytosolic, mitochondrial, or extracellular O2 (·-) enhance afferent arteriolar contractility and remodeling. Although remodeling does not enhance contractility, it does prevent the potentially damaging effects of increased wall stress.
Collapse
Affiliation(s)
- Lingli Li
- From the Department of Medicine, Division of Nephrology and Hypertension, Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, DC (L.L., D.F., Z.L., W.J.W., C.S.W., E.Y.L.); and Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China (E.Y.L.)
| | - Di Feng
- From the Department of Medicine, Division of Nephrology and Hypertension, Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, DC (L.L., D.F., Z.L., W.J.W., C.S.W., E.Y.L.); and Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China (E.Y.L.)
| | - Zaiming Luo
- From the Department of Medicine, Division of Nephrology and Hypertension, Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, DC (L.L., D.F., Z.L., W.J.W., C.S.W., E.Y.L.); and Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China (E.Y.L.)
| | - William J Welch
- From the Department of Medicine, Division of Nephrology and Hypertension, Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, DC (L.L., D.F., Z.L., W.J.W., C.S.W., E.Y.L.); and Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China (E.Y.L.)
| | - Christopher S Wilcox
- From the Department of Medicine, Division of Nephrology and Hypertension, Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, DC (L.L., D.F., Z.L., W.J.W., C.S.W., E.Y.L.); and Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China (E.Y.L.)
| | - En Yin Lai
- From the Department of Medicine, Division of Nephrology and Hypertension, Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, DC (L.L., D.F., Z.L., W.J.W., C.S.W., E.Y.L.); and Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China (E.Y.L.).
| |
Collapse
|
34
|
Fry BC, Edwards A, Layton AT. Impacts of nitric oxide and superoxide on renal medullary oxygen transport and urine concentration. Am J Physiol Renal Physiol 2015; 308:F967-80. [PMID: 25651567 DOI: 10.1152/ajprenal.00600.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/20/2015] [Indexed: 12/17/2022] Open
Abstract
The goal of this study was to investigate the reciprocal interactions among oxygen (O2), nitric oxide (NO), and superoxide (O2 (-)) and their effects on medullary oxygenation and urinary output. To accomplish that goal, we developed a detailed mathematical model of solute transport in the renal medulla of the rat kidney. The model represents the radial organization of the renal tubules and vessels, which centers around the vascular bundles in the outer medulla and around clusters of collecting ducts in the inner medulla. Model simulations yield significant radial gradients in interstitial fluid oxygen tension (Po2) and NO and O2 (-) concentration in the OM and upper IM. In the deep inner medulla, interstitial fluid concentrations become much more homogeneous, as the radial organization of tubules and vessels is not distinguishable. The model further predicts that due to the nonlinear interactions among O2, NO, and O2 (-), the effects of NO and O2 (-) on sodium transport, osmolality, and medullary oxygenation cannot be gleaned by considering each solute's effect in isolation. An additional simulation suggests that a sufficiently large reduction in tubular transport efficiency may be the key contributing factor, more so than oxidative stress alone, to hypertension-induced medullary hypoxia. Moreover, model predictions suggest that urine Po2 could serve as a biomarker for medullary hypoxia and a predictor of the risk for hospital-acquired acute kidney injury.
Collapse
Affiliation(s)
- Brendan C Fry
- Department of Mathematics, Duke University, Durham, North Carolina; and
| | - Aurélie Edwards
- University of Paris 6, University of Paris 5, Institut National de la Santé et de la Recherche Médicale UMRS 1138, Centre National de la Recherche Scientifique ERL 8228, Centre de Recherche des Cordeliers, Paris, France
| | - Anita T Layton
- Department of Mathematics, Duke University, Durham, North Carolina; and
| |
Collapse
|
35
|
Crajoinas RO, Pessoa TD, Rodrigues MV, Malnic G, Girardi ACC. Changes in the activity and expression of protein phosphatase-1 accompany the differential regulation of NHE3 before and after the onset of hypertension in spontaneously hypertensive rats. Acta Physiol (Oxf) 2014; 211:395-408. [PMID: 24666699 DOI: 10.1111/apha.12288] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 11/18/2013] [Accepted: 03/18/2014] [Indexed: 12/14/2022]
Abstract
AIM The Na(+) /H(+) exchanger NHE3 activity decreases in the proximal tubule of spontaneously hypertensive rats (SHRs) as blood pressure increases, and this reduction is correlated with higher NHE3 phosphorylation levels at the PKA consensus site serine 552. This study tested the hypothesis that this lowered NHE3 activity is associated with an increase in PKA activity and expression, and/or a decrease in protein phosphatase-1 (PP1) activity and expression. METHODS Proximal tubule NHE3 activity was measured as the rate of bicarbonate reabsorption by stationary microperfusion. NHE3 phosphorylation and protein expression were determined by immunoblotting. PKA and PP1 activities were determined using specific substrates under optimal enzymatic conditions. RESULTS The PKA activator, 6-MB-cAMP, increased the phosphorylation levels of NHE3 at serine 552 in the renal cortex; this increase happens to a much greater extent in young pre-hypertensive SHRs (Y-SHRs) compared to adult SHRs with established hypertension (A-SHRs). Likewise, the inhibitory effect of 6-MB-cAMP on NHE3 transport activity was much more pronounced in the proximal tubules of Y-SHRs than in those of A-SHRs. Renal cortical activity of PKA was not significantly different between Y-SHRs and A-SHRs. On the other hand, Y-SHRs exhibited higher protein phosphatase 1 (PP1) activity, and their expression of the PP1 catalytic subunit PP1α in the renal cortex was also higher than in A-SHRs. CONCLUSION Collectively, these results support the idea that the lower NHE3 transport activity and higher phosphorylation occurring after the development of hypertension in SHRs are due, at least in part, to reduced PP1-mediated dephosphorylation of NHE3 at serine 552.
Collapse
Affiliation(s)
- R. O. Crajoinas
- Laboratory of Genetics and Molecular Cardiology; Heart Institute (InCor); University of São Paulo Medical School; São Paulo Brazil
| | - T. D. Pessoa
- Department of Physiology and Biophysics; Institute of Biomedical Sciences; University of São Paulo; São Paulo Brazil
| | - M. V. Rodrigues
- Laboratory of Genetics and Molecular Cardiology; Heart Institute (InCor); University of São Paulo Medical School; São Paulo Brazil
| | - G. Malnic
- Department of Physiology and Biophysics; Institute of Biomedical Sciences; University of São Paulo; São Paulo Brazil
| | - A. C. C. Girardi
- Laboratory of Genetics and Molecular Cardiology; Heart Institute (InCor); University of São Paulo Medical School; São Paulo Brazil
| |
Collapse
|
36
|
Renal molecular mechanisms underlying altered Na+ handling and genesis of hypertension during adulthood in prenatally undernourished rats. Br J Nutr 2014; 111:1932-44. [PMID: 24661554 DOI: 10.1017/s0007114513004236] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In the present study, we investigated the development of hypertension in prenatally undernourished adult rats, including the mechanisms that culminate in dysfunctions of molecular signalling in the kidney. Dams were fed a low-protein multideficient diet throughout gestation with or without α-tocopherol during lactation. The time course of hypertension development followed in male offspring was correlated with alterations in proximal tubule Na+-ATPase activity, expression of angiotensin II (Ang II) receptors, and activity of protein kinases C and A. After the establishment of hypertension, Ang II levels, cyclo-oxygenase 2 (COX-2) and NADPH oxidase subunit expression, lipid peroxidation and macrophage infiltration were examined in renal tissue. Lipid peroxidation in undernourished rats, which was very intense at 60 d, decreased at 90 d and returned to control values by 150 d. During the prehypertensive phase, prenatally undernourished rats exhibited elevated renal Na+-ATPase activity, type 2 Ang II receptor down-regulation and altered protein kinase A:protein kinase C ratio. Stable late hypertension coexisted with highly elevated levels of Ang II-positive cells in the cortical tubulointerstitium, enhanced increase in the expression of p47phox (NADPH oxidase regulatory subunit), marked down-regulation of COX-2 expression, expanded plasma volume and decreased creatinine clearance. These alterations were reduced when the dams were given α-tocopherol during lactation. The offspring of well-nourished dams treated with α-tocopherol exhibited most of the alterations encountered in the offspring of undernourished dams not treated with α-tocopherol. Thus, alterations in proximal tubule Na+ transport, subcellular signalling pathways and reactive oxygen species handling in renal tissue underpin the development of hypertension.
Collapse
|
37
|
Healy V, Thompson C, Johns EJ. The adrenergic regulation of proximal tubular Na⁺/H⁺ exchanger 3 in the rat. Acta Physiol (Oxf) 2014; 210:678-89. [PMID: 24118769 DOI: 10.1111/apha.12181] [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: 08/01/2013] [Revised: 08/29/2013] [Accepted: 10/06/2013] [Indexed: 11/27/2022]
Abstract
AIM This study in the anaesthetized rat investigated how renal sympathetic nerve activity and catecholamine release influenced NHE3 abundance and activity in proximal tubular brush border membranes using both in vivo and in vitro approaches. METHODS Renal excretory function and brush border NHE3 abundance and activity were measured in rat kidneys which underwent renal denervation, renal nerve electrical stimulation and renal infusion of phenylephrine and the NHE3 inhibitor S1661. NHE3 activity and cell surface abundance were also measured in primary cultures of proximal tubular cells treated with noradrenaline and prazosin. RESULTS Acute renal denervation caused a natriuresis and diuresis, which occurred with a reduction in NHE3 abundance and activity in the brush border membranes. By contrast, low-level electrical stimulation of the renal innervation causing an antinatriuresis and antidiuresis increased NHE3 activity in the brush border membranes. Intrarenal infusion of phenylephrine caused an antinatriuresis and antidiuresis, while blockade of NHE3 activity, using local infusion of the blocker S1661, caused a natriuresis and diuresis. Exposure of primary cultures of proximal tubular cells to noradrenaline increased brush border NHE3 abundance and activity which was blocked by prior exposure to prazosin, indicating it as an α1 -adrenoceptor-mediated mechanism. CONCLUSION Together, these findings demonstrate that the renal sympathetic nerves not only have a direct action to modulate tubular sodium reabsorption via stimulation of the NHE transporter, but also have an indirect effect, whereby NHE3 abundance is increased within the brush border membrane, thereby increasing the capacity for fluid reabsorption.
Collapse
Affiliation(s)
- V. Healy
- Department of Physiology; University College Cork; Cork Ireland
| | - C. Thompson
- Department of Physiology; University College Cork; Cork Ireland
| | - E. J. Johns
- Department of Physiology; University College Cork; Cork Ireland
| |
Collapse
|
38
|
Abstract
SIGNIFICANCE Renal oxidative stress can be a cause, a consequence, or more often a potentiating factor for hypertension. Increased reactive oxygen species (ROS) in the kidney have been reported in multiple models of hypertension and related to renal vasoconstriction and alterations of renal function. Nicotinamide adenine dinucleotide phosphate oxidase is the central source of ROS in the hypertensive kidney, but a defective antioxidant system also can contribute. RECENT ADVANCES Superoxide has been identified as the principal ROS implicated for vascular and tubular dysfunction, but hydrogen peroxide (H2O2) has been implicated in diminishing preglomerular vascular reactivity, and promoting medullary blood flow and pressure natriuresis in hypertensive animals. CRITICAL ISSUES AND FUTURE DIRECTIONS Increased renal ROS have been implicated in renal vasoconstriction, renin release, activation of renal afferent nerves, augmented contraction, and myogenic responses of afferent arterioles, enhanced tubuloglomerular feedback, dysfunction of glomerular cells, and proteinuria. Inhibition of ROS with antioxidants, superoxide dismutase mimetics, or blockers of the renin-angiotensin-aldosterone system or genetic deletion of one of the components of the signaling cascade often attenuates or delays the onset of hypertension and preserves the renal structure and function. Novel approaches are required to dampen the renal oxidative stress pathways to reduced O2(-•) rather than H2O2 selectivity and/or to enhance the endogenous antioxidant pathways to susceptible subjects to prevent the development and renal-damaging effects of hypertension.
Collapse
Affiliation(s)
- Magali Araujo
- Hypertension, Kidney and Vascular Research Center, Georgetown University , Washington, District of Columbia
| | | |
Collapse
|
39
|
Paixão AD, Alexander BT. How the kidney is impacted by the perinatal maternal environment to develop hypertension. Biol Reprod 2013; 89:144. [PMID: 24227755 DOI: 10.1095/biolreprod.113.111823] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Environmental conditions during perinatal development such as maternal undernutrition, maternal glucocorticoids, placental insufficiency, and maternal sodium overload can program changes in renal Na(+) excretion leading to hypertension. Experimental studies indicate that fetal exposure to an adverse maternal environment may reduce glomerular filtration rate by decreasing the surface area of the glomerular capillaries. Moreover, fetal responses to environmental insults during early life that contribute to the development of hypertension may include increased expression of tubular apical or basolateral membrane Na(+) transporters and increased production of renal superoxide leading to enhanced Na(+) reabsorption. This review will address the role of these potential renal mechanisms in the fetal programming of hypertension in experimental models induced by maternal undernutrition, fetal exposure to glucocorticoids, placental insufficiency, and maternal sodium overload in the rat.
Collapse
Affiliation(s)
- Ana D Paixão
- Department of Physiology and Pharmacology, Center of Biological Sciences, Federal University of Pernambuco, Recife, Brazil
| | | |
Collapse
|
40
|
Stockand JD, Vallon V, Ortiz P. In vivo and ex vivo analysis of tubule function. Compr Physiol 2013; 2:2495-525. [PMID: 23720256 DOI: 10.1002/cphy.c100051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Analysis of tubule function with in vivo and ex vivo approaches has been instrumental in revealing renal physiology. This work allows assignment of functional significance to known gene products expressed along the nephron, primary of which are proteins involved in electrolyte transport and regulation of these transporters. Not only we have learned much about the key roles played by these transport proteins and their proper regulation in normal physiology but also the combination of contemporary molecular biology and molecular genetics with in vivo and ex vivo analysis opened a new era of discovery informative about the root causes of many renal diseases. The power of in vivo and ex vivo analysis of tubule function is that it preserves the native setting and control of the tubule and proteins within tubule cells enabling them to be investigated in a "real-life" environment with a high degree of precision. In vivo and ex vivo analysis of tubule function continues to provide a powerful experimental outlet for testing, evaluating, and understanding physiology in the context of the novel information provided by sequencing of the human genome and contemporary genetic screening. These tools will continue to be a mainstay in renal laboratories as this discovery process continues and as we continue to identify new gene products functionally compromised in renal disease.
Collapse
Affiliation(s)
- James D Stockand
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, USA.
| | | | | |
Collapse
|
41
|
Hansell P, Welch WJ, Blantz RC, Palm F. Determinants of kidney oxygen consumption and their relationship to tissue oxygen tension in diabetes and hypertension. Clin Exp Pharmacol Physiol 2013. [PMID: 23181475 DOI: 10.1111/1440-1681.12034] [Citation(s) in RCA: 209] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The high renal oxygen (O(2) ) demand is associated primarily with tubular O(2) consumption (Qo(2) ) necessary for solute reabsorption. Increasing O(2) delivery relative to demand via increased blood flow results in augmented tubular electrolyte load following elevated glomerular filtration, which, in turn, increases metabolic demand. Consequently, elevated kidney metabolism results in decreased tissue oxygen tension. The metabolic efficiency for solute transport (Qo(2) /T(Na) ) varies not only between different nephron sites, but also under different conditions of fluid homeostasis and disease. Contributing mechanisms include the presence of different Na(+) transporters, different levels of oxidative stress and segmental tubular dysfunction. Sustained hyperglycaemia results in increased kidney Qo(2) , partly due to mitochondrial dysfunction and reduced electrolyte transport efficiency. This results in intrarenal tissue hypoxia because the increased Qo(2) is not matched by a similar increase in O(2) delivery. Hypertension leads to renal hypoxia, mediated by increased angiotensin receptor tonus and oxidative stress. Reduced uptake in the proximal tubule increases load to the thick ascending limb. There, the increased load is reabsorbed, but at greater O(2) cost. The combination of hypertension, angiotensin II and oxidative stress initiates events leading to renal damage and reduced function. Tissue hypoxia is now recognized as a unifying pathway to chronic kidney disease. We have gained good knowledge about major changes in O(2) metabolism occurring in diabetic and hypertensive kidneys. However, further efforts are needed to elucidate how these alterations can be prevented or reversed before translation into clinical practice.
Collapse
Affiliation(s)
- Peter Hansell
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
| | | | | | | |
Collapse
|
42
|
Yan Y, Shapiro AP, Haller S, Katragadda V, Liu L, Tian J, Basrur V, Malhotra D, Xie ZJ, Abraham NG, Shapiro JI, Liu J. Involvement of reactive oxygen species in a feed-forward mechanism of Na/K-ATPase-mediated signaling transduction. J Biol Chem 2013; 288:34249-34258. [PMID: 24121502 DOI: 10.1074/jbc.m113.461020] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cardiotonic steroids (such as ouabain) signaling through Na/K-ATPase regulate sodium reabsorption in the renal proximal tubule. We report here that reactive oxygen species are required to initiate ouabain-stimulated Na/K-ATPase·c-Src signaling. Pretreatment with the antioxidant N-acetyl-L-cysteine prevented ouabain-stimulated Na/K-ATPase·c-Src signaling, protein carbonylation, redistribution of Na/K-ATPase and sodium/proton exchanger isoform 3, and inhibition of active transepithelial (22)Na(+) transport. Disruption of the Na/K-ATPase·c-Src signaling complex attenuated ouabain-stimulated protein carbonylation. Ouabain-stimulated protein carbonylation is reversed after removal of ouabain, and this reversibility is largely independent of de novo protein synthesis and degradation by either the lysosome or the proteasome pathways. Furthermore, ouabain stimulated direct carbonylation of two amino acid residues in the actuator domain of the Na/K-ATPase α1 subunit. Taken together, the data indicate that carbonylation modification of the Na/K-ATPase α1 subunit is involved in a feed-forward mechanism of regulation of ouabain-mediated renal proximal tubule Na/K-ATPase signal transduction and subsequent sodium transport.
Collapse
Affiliation(s)
- Yanling Yan
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine at Marshall University, Huntington, West Virginia 25755; Institute of Biomedical Engineering, Yanshan University, Qinhuangdao 066004, China
| | - Anna P Shapiro
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Steven Haller
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Vinai Katragadda
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Lijun Liu
- Department of Pharmacology, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Jiang Tian
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio 43614; Department of Pharmacology, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Venkatesha Basrur
- Department of Pathology, University of Michigan, Ann Arbor, Michigan 48109
| | - Deepak Malhotra
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Zi-Jian Xie
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio 43614; Department of Pharmacology, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Nader G Abraham
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine at Marshall University, Huntington, West Virginia 25755
| | - Joseph I Shapiro
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine at Marshall University, Huntington, West Virginia 25755; Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Jiang Liu
- Department of Pharmacology, Physiology and Toxicology, JCE School of Medicine at Marshall University, Huntington, West Virginia 25755.
| |
Collapse
|
43
|
Sedeek M, Nasrallah R, Touyz RM, Hébert RL. NADPH oxidases, reactive oxygen species, and the kidney: friend and foe. J Am Soc Nephrol 2013; 24:1512-8. [PMID: 23970124 DOI: 10.1681/asn.2012111112] [Citation(s) in RCA: 339] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Reactive oxygen species (ROS) play an important role in normal cellular physiology. They regulate different biologic processes such as cell defense, hormone synthesis and signaling, activation of G protein-coupled receptors, and ion channels and kinases/phosphatases. ROS are also important regulators of transcription factors and gene expression. On the other hand, in pathologic conditions, a surplus of ROS in tissue results in oxidative stress with various injurious consequences such as inflammation and fibrosis. NADPH oxidases are one of the many sources of ROS in biologic systems, and there are seven isoforms (Nox1-5, Duox1, Duox2). Nox4 is the predominant form in the kidney, although Nox2 is also expressed. Nox4 has been implicated in the basal production of ROS in the kidney and in pathologic conditions such as diabetic nephropathy and CKD; upregulation of Nox4 may be important in renal oxidative stress and kidney injury. Although there is growing evidence indicating the involvement of NADPH oxidase in renal pathology, there is a paucity of information on the role of NADPH oxidase in the regulation of normal renal function. Here we provide an update on the role of NADPH oxidases and ROS in renal physiology and pathology.
Collapse
Affiliation(s)
- Mona Sedeek
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | | | | | | |
Collapse
|
44
|
Abstract
The kidney plays a fundamental role in maintaining body salt and fluid balance and blood pressure homeostasis through the actions of its proximal and distal tubular segments of nephrons. However, proximal tubules are well recognized to exert a more prominent role than distal counterparts. Proximal tubules are responsible for reabsorbing approximately 65% of filtered load and most, if not all, of filtered amino acids, glucose, solutes, and low molecular weight proteins. Proximal tubules also play a key role in regulating acid-base balance by reabsorbing approximately 80% of filtered bicarbonate. The purpose of this review article is to provide a comprehensive overview of new insights and perspectives into current understanding of proximal tubules of nephrons, with an emphasis on the ultrastructure, molecular biology, cellular and integrative physiology, and the underlying signaling transduction mechanisms. The review is divided into three closely related sections. The first section focuses on the classification of nephrons and recent perspectives on the potential role of nephron numbers in human health and diseases. The second section reviews recent research on the structural and biochemical basis of proximal tubular function. The final section provides a comprehensive overview of new insights and perspectives in the physiological regulation of proximal tubular transport by vasoactive hormones. In the latter section, attention is particularly paid to new insights and perspectives learnt from recent cloning of transporters, development of transgenic animals with knockout or knockin of a particular gene of interest, and mapping of signaling pathways using microarrays and/or physiological proteomic approaches.
Collapse
Affiliation(s)
- Jia L Zhuo
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, USA.
| | | |
Collapse
|
45
|
Cardoso AM, Martins CC, Fiorin FDS, Schmatz R, Abdalla FH, Gutierres J, Zanini D, Fiorenza AM, Stefanello N, Serres JDDS, Carvalho F, Castro VP, Mazzanti CM, Royes LFF, Belló-Klein A, Goularte JF, Morsch VM, Bagatini MD, Schetinger MRC. Physical training prevents oxidative stress in L-NAME-induced hypertension rats. Cell Biochem Funct 2012; 31:136-51. [DOI: 10.1002/cbf.2868] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 06/26/2012] [Accepted: 07/30/2012] [Indexed: 01/01/2023]
Affiliation(s)
- Andréia Machado Cardoso
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Caroline Curry Martins
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Fernando da Silva Fiorin
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Roberta Schmatz
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Fátima Husein Abdalla
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Jessié Gutierres
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Daniela Zanini
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Amanda Maino Fiorenza
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Naiara Stefanello
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Jonas Daci da Silva Serres
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Fabiano Carvalho
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Verônica Paiva Castro
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Cinthia Melazzo Mazzanti
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Luiz Fernando Freire Royes
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | - Adriane Belló-Klein
- Health Basic Sciences Institut, Department of Physiology; Federal University of Rio Grande do Sul; Porto Alegre; RS; Brazil
| | - Jeferson Ferraz Goularte
- Health Basic Sciences Institut, Department of Physiology; Federal University of Rio Grande do Sul; Porto Alegre; RS; Brazil
| | - Vera Maria Morsch
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| | | | - Maria Rosa Chitolina Schetinger
- Post-Graduation Program in Toxicological Biochemistry, Department of Chemistry of the Center of Natural and Exact Sciences; Federal University of Santa Maria; Santa Maria; RS; Brazil
| |
Collapse
|
46
|
Lee DL, Bell TD, Bhupatkar J, Solis G, Welch WJ. Adenosine A1-receptor knockout mice have a decreased blood pressure response to low-dose ANG II infusion. Am J Physiol Regul Integr Comp Physiol 2012; 303:R683-8. [PMID: 22874421 DOI: 10.1152/ajpregu.00116.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adenosine, acting on A(1)-receptors (A(1)-AR) in the nephron, increases sodium reabsorption, and also increases renal vascular resistance (RVR), via A(1)-ARs in the afferent arteriole. ANG II increases blood pressure and RVR, and it stimulates adenosine release in the kidney. We tested the hypothesis that ANG II-infused hypertension is potentiated by A(1)-ARs' influence on Na(+) reabsorption. Mean arterial pressure (MAP) was measured by radiotelemetry in A(1)-AR knockout mice (KO) and their wild-type (WT) controls, before and during ANG II (400 ng·kg(-1)·min(-1)) infusion. Baseline MAP was not different between groups. ANG II increased MAP in both groups, but on day 12, MAP was lower in A(1)-AR KO mice (KO: 128 ± 3 vs. 139 ± 3 mmHg, P < 0.01). Heart rates were significantly different during days 11-14 of ANG II. Basal sodium excretion was not different (KO: 0.15 ± 0.03 vs. WT: 0.13 ± 0.04 mmol/day, not significant) but was higher in KO mice 12 days after ANG II despite a lower MAP (KO: 0.22 ± 0.03 vs. WT: 0.11 ± 0.02 mmol/day, P < 0.05). Phosphate excretion was also higher in A(1)-AR KO mice on day 12. Renal expression of the sodium-dependent phosphate transporter and the Na(+)/glucose cotransporter were lower in the KO mice during ANG II treatment, but the expression of the sodium hydrogen exchanger isoform 3 was not different. These results indicate that the increase in blood pressure seen in A(1)-AR KO mice is lower than that seen in WT mice but was increased by ANG II nonetheless. The presence of A(1)-ARs during a low dose of ANG II-infusion limits Na(+) and phosphate excretion. This study suggests that A(1)-AR antagonists might be an effective antihypertensive agent during ANG II and volume-dependent hypertension.
Collapse
Affiliation(s)
- Dexter L Lee
- Department of Physiology and Biophysics, Howard University, Washington, DC, USA
| | | | | | | | | |
Collapse
|
47
|
The NADPH oxidase family and its inhibitors. Arch Immunol Ther Exp (Warsz) 2012; 60:277-94. [PMID: 22696046 DOI: 10.1007/s00005-012-0176-z] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 03/27/2012] [Indexed: 12/16/2022]
Abstract
The classical nicotinamide adenine dinucleotide phosphate (NADPH) oxidase was originally detected in neutrophils as a multicomponent enzyme that catalyzes the generation of superoxide from oxygen and the reduced form of NADPH. This enzyme is composed of two membrane-bound subunits (p22phox and gp91phox), three cytosolic subunits (p67phox, p47phox, and p40phox) and a small G-protein Rac (Rac1 and Rac2). Recently, it has been demonstrated that there are several isoforms of nonphagocytic NADPH oxidase. Endothelial cells, vascular smooth muscle cells or adventitial fibroblasts possess multiple isoforms of this enzyme. The new homologs, along with gp91phox are now designated the Nox family of NADPH oxidases and are key sources of reactive oxygen species in the vasculature. Reactive oxygen species play a significant role in regulating endothelial function and vascular tone. However, besides the participation in the processes of physiological cell, these enzymes can also be the perpetrator of oxidative stress that causes endothelial dysfunction. This review summarizes the current state of knowledge of the structure and functions of NADPH oxidase and NADPH oxidase inhibitors in the treatment of disorders with endothelial damage.
Collapse
|
48
|
Girardi ACC, Di Sole F. Deciphering the mechanisms of the Na+/H+ exchanger-3 regulation in organ dysfunction. Am J Physiol Cell Physiol 2012; 302:C1569-87. [DOI: 10.1152/ajpcell.00017.2012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The Na+/H+ exchanger-3 (NHE3) belongs to the mammalian NHE protein family and catalyzes the electro-neutral exchange of extracellular sodium for intracellular proton across cellular membranes. Its transport function is of essential importance for the maintenance of the body's salt and water homeostasis as well as acid-base balance. Indeed, NHE3 activity is finely regulated by a variety of stimuli, both acutely and chronically, and its transport function is fundamental for a multiplicity of severe and world-wide infection-pathological conditions. This review aims to provide a concise overview of NHE3 physiology and discusses the role of NHE3 in clinical conditions of prominent importance, specifically in hypertension, diabetic nephropathy, heart failure, acute kidney injury, and diarrhea. Study of NHE3 function in models of these diseases has contributed to the deciphering of mechanisms that control the delicate ion balance disrupted in these disorders. The majority of the findings indicate that NHE3 transport function is activated before the onset of hypertension and inhibited thereafter; NHE3 transport function is also upregulated in diabetic nephropathy and heart failure, while it is reported to be downregulated in acute kidney injury and in diarrhea. The molecular mechanisms activated during these pathological conditions to regulate NHE3 transport function are examined with the aim of linking NHE3 dysfunction to the analyzed clinical disorders.
Collapse
Affiliation(s)
| | - Francesca Di Sole
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas; and
- Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas
| |
Collapse
|
49
|
Reactive Oxygen Species Modulation of Na/K-ATPase Regulates Fibrosis and Renal Proximal Tubular Sodium Handling. Int J Nephrol 2012; 2012:381320. [PMID: 22518311 PMCID: PMC3299271 DOI: 10.1155/2012/381320] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 11/07/2011] [Indexed: 01/11/2023] Open
Abstract
The Na/K-ATPase is the primary force regulating renal sodium handling and plays a key role in both ion homeostasis and blood pressure regulation. Recently, cardiotonic steroids (CTS)-mediated Na/K-ATPase signaling has been shown to regulate fibrosis, renal proximal tubule (RPT) sodium reabsorption, and experimental Dahl salt-sensitive hypertension in response to a high-salt diet. Reactive oxygen species (ROS) are an important modulator of nephron ion transport. As there is limited knowledge regarding the role of ROS-mediated fibrosis and RPT sodium reabsorption through the Na/K-ATPase, the focus of this review is to examine the possible role of ROS in the regulation of Na/K-ATPase activity, its signaling, fibrosis, and RPT sodium reabsorption.
Collapse
|
50
|
Lob HE, Vinh A, Li L, Blinder Y, Offermanns S, Harrison DG. Role of vascular extracellular superoxide dismutase in hypertension. Hypertension 2011; 58:232-9. [PMID: 21730294 DOI: 10.1161/hypertensionaha.111.172718] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Previous studies indicate that superoxide is important in the modulation of blood pressure but have not specifically identified the cell types or organs involved. We created mice with loxP sites flanking the extracellular superoxide dismutase (SOD3) gene. These mice were crossed with mice expressing inducible Cre-recombinase driven by the smooth muscle myosin heavy chain promoter allowing tissue-specific deletion of SOD3. Deletion of SOD3 increased vascular superoxide and reduced vascular NO levels as detected by electron spin resonance. Despite these changes in NO and superoxide, we did not observe increases in vascular inflammation caused by angiotensin II. Moreover, deletion of vascular SOD3 did not augment hypertension in response to angiotensin II. In additional studies, we also deleted SOD3 from the circumventricular organs by intracerebroventricular injection of an adenovirus encoding Cre-recombinase. Although this raised blood pressure and augmented the hypertension caused by angiotensin II, these responses were not further increased by vascular deletion of SOD3. These data suggest that the extracellular superoxide dismutase in vascular smooth muscle is not involved in the genesis of angiotensin II-induced hypertension and further emphasize the role of central SOD3 in the modulation of blood pressure.
Collapse
Affiliation(s)
- Heinrich E Lob
- Division of Clinical Pharmacology, 536 Robinson Research Building, Vanderbilt University School of Medicine, Nashville, TN 37232-6602, USA
| | | | | | | | | | | |
Collapse
|