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Goltsman I, Khoury EE, Aronson D, Nativ O, Feuerstein GZ, Winaver J, Abassi Z. Rosiglitazone treatment restores renal responsiveness to atrial natriuretic peptide in rats with congestive heart failure. J Cell Mol Med 2019; 23:4779-4794. [PMID: 31087547 PMCID: PMC6584517 DOI: 10.1111/jcmm.14366] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 03/24/2019] [Accepted: 04/01/2019] [Indexed: 12/28/2022] Open
Abstract
The thiazolidinedione (TZD) class of Peroxisome proliferator‐activated receptor gamma agonists has restricted clinical use for diabetes mellitus due to fluid retention and potential cardiovascular risks. These side effects are attributed in part to direct salt‐retaining effect of TZDs at the renal collecting duct. A recent study from our group revealed that prolonged rosiglitazone (RGZ) treatment caused no Na+/H2O retention or up‐regulation of Na+ transport‐linked channels/transporters in experimental congestive heart failure (CHF) induced by surgical aorto‐caval fistula (ACF). The present study examines the effects of RGZ on renal and cardiac responses to atrial natriuretic peptide (ANP), Acetylcholine (Ach) and S‐Nitroso‐N‐acetylpenicillamine (SNAP‐NO donor). Furthermore, we assessed the impact of RGZ on gene expression related to the ANP signalling pathway in animals with ACF. Rats subjected to ACF (or sham) were treated with either RGZ (30 mg/kg/day) or vehicle for 4 weeks. Cardiac chambers pressures and volumes were assessed invasively via Miller catheter. Kidney excretory and renal hemodynamic in response to ANP, Ach and SNAP were examined. Renal clearance along with cyclic guanosine monophosphate (cGMP), gene expression of renal CHF‐related genes and ANP signalling in the kidney were determined. RGZ‐treated CHF rats exhibited significant improvement in the natriuretic responses to ANP infusion. This ‘sensitization’ to ANP was not associated with increases in neither urinary cGMP nor in vitro cGMP production. However, RGZ caused down‐regulation of several genes in the renal cortex (Ace, Nos3 and Npr1) and up‐regulation of ACE2, Agtrla, Mme and Cftr along down‐regulation of Avpr2, Npr1,2, Nos3 and Pde3 in the medulla. In conclusion, CHF+RGZ rats exhibited significant enhancement in the natriuretic responses to ANP infusion, which are known to be blunted in CHF. This ‘sensitization’ to ANP is independent of cGMP signalling, yet may involve post‐cGMP signalling target genes such as ACE2, CFTR and V2 receptor. The possibility that TZD treatment in uncomplicated CHF may be less detrimental than thought before deserves additional investigations.
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Affiliation(s)
- Ilia Goltsman
- Department of Physiology, Bruce Rappaport Faculty of Medicine, Technion-IIT, Haifa, Israel
| | - Emad E Khoury
- Department of Physiology, Bruce Rappaport Faculty of Medicine, Technion-IIT, Haifa, Israel
| | - Doron Aronson
- Department of Cardiology, Rambam Health Care Campus, Haifa, Israel
| | - Omri Nativ
- Department of Physiology, Bruce Rappaport Faculty of Medicine, Technion-IIT, Haifa, Israel
| | - Giora Z Feuerstein
- Department of Cardiology, Rambam Health Care Campus, Haifa, Israel.,FARMACON LLC, Translational Medicine Company, Bryn Mawr, Pennsylvania
| | - Joseph Winaver
- Department of Physiology, Bruce Rappaport Faculty of Medicine, Technion-IIT, Haifa, Israel
| | - Zaid Abassi
- Department of Physiology, Bruce Rappaport Faculty of Medicine, Technion-IIT, Haifa, Israel.,Department of Laboratory Medicine, Rambam Health Care Campus, Haifa, Israel
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Goltsman I, Khoury EE, Winaver J, Abassi Z. Does Thiazolidinedione therapy exacerbate fluid retention in congestive heart failure? Pharmacol Ther 2016; 168:75-97. [PMID: 27598860 DOI: 10.1016/j.pharmthera.2016.09.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The ever-growing global burden of congestive heart failure (CHF) and type 2 diabetes mellitus (T2DM) as well as their co-existence necessitate that anti-diabetic pharmacotherapy will modulate the cardiovascular risk inherent to T2DM while complying with the accompanying restrictions imposed by CHF. The thiazolidinedione (TZD) family of peroxisome proliferator-activated receptor γ (PPARγ) agonists initially provided a promising therapeutic option in T2DM owing to anti-diabetic efficacy combined with pleiotropic beneficial cardiovascular effects. However, the utility of TZDs in T2DM has declined in the past decade, largely due to concomitant adverse effects of fluid retention and edema formation attributed to salt-retaining effects of PPARγ activation on the nephron. Presumably, the latter effects are potentially deleterious in the context of pre-existing fluid retention in CHF. However, despite a considerable body of evidence on mechanisms responsible for TZD-induced fluid retention suggesting that this class of drugs is rightfully prohibited from use in CHF patients, there is a paucity of experimental and clinical studies that investigate the effects of TZDs on salt and water homeostasis in the CHF setting. In an attempt to elucidate whether TZDs actually exacerbate the pre-existing fluid retention in CHF, our review summarizes the pathophysiology of fluid retention in CHF. Moreover, we thoroughly review the available data on TZD-induced fluid retention and proposed mechanisms in animals and patients. Finally, we will present recent studies challenging the common notion that TZDs worsen renal salt and water retention in CHF.
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Affiliation(s)
- Ilia Goltsman
- Department of Physiology, Biophysics and Systems Biology, The Bruce Rappaport, Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Emad E Khoury
- Department of Physiology, Biophysics and Systems Biology, The Bruce Rappaport, Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Joseph Winaver
- Department of Physiology, Biophysics and Systems Biology, The Bruce Rappaport, Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Zaid Abassi
- Department of Physiology, Biophysics and Systems Biology, The Bruce Rappaport, Rappaport Faculty of Medicine, Technion, Haifa, Israel; Department of Laboratory Medicine, Rambam Human Health Care Campus, Haifa, Israel.
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Abdulla MH, Sattar MA, Johns EJ. Effects of tempol on altered metabolism and renal vascular responsiveness in fructose-fed rats. Appl Physiol Nutr Metab 2016; 41:210-8. [DOI: 10.1139/apnm-2015-0411] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
This study investigated the effect of tempol (a superoxide dismutase mimetic) on renal vasoconstrictor responses to angiotensin II (Ang II) and adrenergic agonists in fructose-fed Sprague–Dawley rats (a model of metabolic syndrome). Rats were fed 20% fructose in drinking water (F) for 8 weeks. One fructose-fed group received tempol (FT) at 1 mmol·L–1 in drinking water for 8 weeks or as an infusion (1.5 mg·kg–1·min–1) intrarenally. At the end of the treatment regimen, the renal responses to noradrenaline, phenylephrine, methoxamine, and Ang II were determined. F rats exhibited hyperinsulinemia, hyperuricemia, hypertriglyceridemia, and hypertension. Tempol reduced blood glucose and insulin levels (all p < 0.05) in FT rats compared with their untreated counterparts. The vasoconstriction response to all agonists was lower in F rats than in control rats by about 35%–65% (all p < 0.05). Vasoconstrictor responses to noradrenaline, phenylephrine, and methoxamine but not Ang II were about 41%–75% higher in FT rats compared with F rats (all p < 0.05). Acute tempol infusion blunted responses to noradrenaline, methoxamine, and Ang II in control rats by 32%, 33%, and 62%, while it blunted responses to noradrenaline and Ang II in F rats by 26% and 32%, respectively (all p < 0.05), compared with their untreated counterparts. Superoxide radicals play a crucial role in controlling renal vascular responses to adrenergic agonists in insulin-resistant rats. Chronic but not acute tempol treatment enhances renal vascular responsiveness in fructose-fed rats.
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Affiliation(s)
- Mohammed H. Abdulla
- Department of Physiology, School of Medicine, University College Cork, Cork, Ireland
| | - Munavvar A. Sattar
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden, 11800 Penang, Malaysia
| | - Edward J. Johns
- Department of Physiology, School of Medicine, University College Cork, Cork, Ireland
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Jiang X, Chen W, Liu X, Wang Z, Liu Y, Felder RA, Gildea JJ, Jose PA, Qin C, Yang Z. The Synergistic Roles of Cholecystokinin B and Dopamine D5 Receptors on the Regulation of Renal Sodium Excretion. PLoS One 2016; 11:e0146641. [PMID: 26751218 PMCID: PMC4709046 DOI: 10.1371/journal.pone.0146641] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 12/21/2015] [Indexed: 01/07/2023] Open
Abstract
Renal dopamine D1-like receptors (D1R and D5R) and the gastrin receptor (CCKBR) are involved in the maintenance of sodium homeostasis. The D1R has been found to interact synergistically with CCKBR in renal proximal tubule (RPT) cells to promote natriuresis and diuresis. D5R, which has a higher affinity for dopamine than D1R, has some constitutive activity. Hence, we sought to investigate the interaction between D5R and CCKBR in the regulation of renal sodium excretion. In present study, we found D5R and CCKBR increase each other’s expression in a concentration- and time-dependent manner in the HK-2 cell, the specificity of which was verified in HEK293 cells heterologously expressing both human D5R and CCKBR and in RPT cells from a male normotensive human. The specificity of D5R in the D5R and CCKBR interaction was verified further using a selective D5R antagonist, LE-PM436. Also, D5R and CCKBR colocalize and co-immunoprecipitate in BALB/c mouse RPTs and human RPT cells. CCKBR protein expression in plasma membrane-enriched fractions of renal cortex (PMFs) is greater in D5R-/- mice than D5R+/+ littermates and D5R protein expression in PMFs is also greater in CCKBR-/- mice than CCKBR+/+ littermates. High salt diet, relative to normal salt diet, increased the expression of CCKBR and D5R proteins in PMFs. Disruption of CCKBR in mice caused hypertension and decreased sodium excretion. The natriuresis in salt-loaded BALB/c mice was decreased by YF476, a CCKBR antagonist and Sch23390, a D1R/D5R antagonist. Furthermore, the natriuresis caused by gastrin was blocked by Sch23390 while the natriuresis caused by fenoldopam, a D1R/D5R agonist, was blocked by YF476. Taken together, our findings indicate that CCKBR and D5R synergistically interact in the kidney, which may contribute to the maintenance of normal sodium balance following an increase in sodium intake.
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Affiliation(s)
- Xiaoliang Jiang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Wei Chen
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Xing Liu
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Zihao Wang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Yunpeng Liu
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Robin A. Felder
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - John J. Gildea
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Pedro A. Jose
- Division of Nephrology, Departments of Medicine and Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (PAJ); (CQ); (ZWY)
| | - Chuan Qin
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
- * E-mail: (PAJ); (CQ); (ZWY)
| | - Zhiwei Yang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
- CollaborativeInnovation Center for Cardiovascular Disorders, Beijing, P. R. China
- * E-mail: (PAJ); (CQ); (ZWY)
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Armando I, Konkalmatt P, Felder RA, Jose PA. The renal dopaminergic system: novel diagnostic and therapeutic approaches in hypertension and kidney disease. Transl Res 2015; 165:505-11. [PMID: 25134060 PMCID: PMC4305499 DOI: 10.1016/j.trsl.2014.07.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/17/2014] [Accepted: 07/19/2014] [Indexed: 12/15/2022]
Abstract
Salt sensitivity of blood pressure, whether in hypertensive or normotensive subjects, is associated with increased cardiovascular risk and overall mortality. Salt sensitivity can be treated by reducing NaCl consumption. However, decreasing salt intake in some may actually increase cardiovascular risk, including an increase in blood pressure, that is, inverse salt sensitivity. Several genes have been associated with salt sensitivity and inverse salt sensitivity. Some of these genes encode proteins expressed in the kidney that are needed to excrete a sodium load, for example, dopamine receptors and their regulators, G protein-coupled receptor kinase 4 (GRK4). We review here research in this field that has provided several translational opportunities, ranging from diagnostic tests to gene therapy, such as (1) a test in renal proximal tubule cells isolated from the urine of humans that may determine the salt-sensitive phenotype by analyzing the recruitment of dopamine D1 receptors to the plasma membrane; (2) the presence of common GRK4 gene variants that are not only associated with hypertension but may also be predictive of the response to antihypertensive therapy; (3) genetic testing for polymorphisms of the dopamine D2 receptor that may be associated with hypertension and inverse salt sensitivity and may increase the susceptibility to chronic kidney disease because of loss of the antioxidant and anti-inflammatory effects of the renal dopamine D2 receptor, and (4) in vivo renal selective amelioration of renal tubular genetic defects by a gene transfer approach, using adeno-associated viral vectors introduced to the kidney by retrograde ureteral infusion.
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Affiliation(s)
- Ines Armando
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Prasad Konkalmatt
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Robin A Felder
- Department of Pathology, The University of Virginia School of Medicine, Charlottesville, VA
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD.
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Luo H, Wang X, Chen C, Wang J, Zou X, Li C, Xu Z, Yang X, Shi W, Zeng C. Oxidative stress causes imbalance of renal renin angiotensin system (RAS) components and hypertension in obese Zucker rats. J Am Heart Assoc 2015; 4:jah3851. [PMID: 25687731 PMCID: PMC4345876 DOI: 10.1161/jaha.114.001559] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Background Oxidative stress plays an important role in the pathogenesis of hypertension, especially in obesity‐related hypertension. The natriuretic and antinatriuretic components of the renal renin angiotensin system (RAS) maintain sodium homeostasis and blood pressure. Here, we test the hypothesis that increased oxidative stress leads to the imbalance of RAS components and hypertension in obese Zucker rats. Methods and Results Lean and obese rats received vehicle or tempol, a superoxide dismutase mimetic in the drinking water for 4 weeks. Compared with vehicle‐treated lean rats, vehicle‐treated obese rats exhibited higher blood pressure and increased renal oxidative stress, accompanied by increased diuretic and natriuretic responses to AT1R antagonist (Candesartan) and AT2R agonist (CGP‐42112A) and reduced diuretic and natriuretic response to MasR agonist (Ang‐[1 to 7]). Moreover, obese rats had higher ACE, AT1R and AT2R, lower ACE2 and MasR expressions in the kidney. All of the above‐mentioned abnormalities were reversed to some degree by tempol treatment. In primary cultures of renal proximal tubular (RPT) cells from lean and obese rats, tempol treatment also increased AT2R, ACE2, and MasR expressions but decreased AT1R and ACE expressions in obese rats. Conclusions Taken together, our study indicated that the imbalance of renal RAS components was associated with increased oxidative stress in obese rats. Furthermore, antioxidant treatment with tempol reversed the imbalance of renal RAS components and led to diuresis and natriuresis, which, at least in part, explains the blood pressure‐lowering effect of antioxidant supplementation in obesity‐related hypertension.
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Affiliation(s)
- Hao Luo
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Xinquan Wang
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Caiyu Chen
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Jialiang Wang
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Xue Zou
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Chuanwei Li
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Zaicheng Xu
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Xiaoli Yang
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Weibin Shi
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, China (H.L., X.W., C.C., J.W., X.Z., C.L., Z.X., X.Y., W.S., C.Z.)
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Fu J, Han Y, Wang H, Wang Z, Liu Y, Chen X, Cai Y, Guan W, Yang D, Asico LD, Zhou L, Jose PA, Zeng C. Impaired dopamine D1 receptor-mediated vasorelaxation of mesenteric arteries in obese Zucker rats. Cardiovasc Diabetol 2014; 13:50. [PMID: 24559270 PMCID: PMC3938077 DOI: 10.1186/1475-2840-13-50] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 02/20/2014] [Indexed: 12/18/2022] Open
Abstract
Background Obesity plays an important role in the pathogenesis of hypertension. Renal dopamine D1-like receptor-mediated diuresis and natriuresis are impaired in the obese Zucker rat, an obesity-related hypertensive rat model. The role of arterial D1 receptors in the hypertension of obese Zucker rats is not clear. Methods Plasma glucose and insulin concentrations and blood pressure were measured. The vasodilatory response of isolated mesenteric arteries was evaluated using a small vessel myograph. The expression and phosphorylation of D1 receptors were quantified by co-immunoprecipitation and immunoblotting To determine the effect of hyperinsulinemia and hyperglycemia on the function of the arterial D1 receptor, we studied obese Zucker rats (six to eight-weeks old) fed (6 weeks) vehicle or rosiglitazone, an insulin sensitizer (10 mg/kg per day) and lean Zucker rats (eight to ten-weeks old), fed high-fat diet to induce hyperinsulinemia or injected intraperitoneally with streptomycin (STZ) to induce hyperglycemia. Results In obese Zucker rats, the vasorelaxant effect of D1-like receptors was impaired that could be ascribed to decreased arterial D1 receptor expression and increased D1 receptor phosphorylation. In these obese rats, rosiglitazone normalized the arterial D1 receptor expression and phosphorylation and improved the D1-like receptor-mediated vasorelaxation. We also found that D1 receptor-dependent vasorelaxation was decreased in lean Zucker rats with hyperinsulinemia or hyperglycemia but the D1 receptor dysfunction was greater in the former than in the latter group. The ability of insulin and glucose to decrease D1 receptor expression and increase its phosphorylation were confirmed in studies of rat aortic smooth muscle cells. Conclusions Both hyperinsulinemia and hyperglycemia caused D1 receptor dysfunction by decreasing arterial D1 receptor expression and increasing D1 receptor phosphorylation. Impaired D1 receptor-mediated vasorelaxation is involved in the pathogenesis of obesity-related hypertension.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Lin Zhou
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, P,R, China.
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Bełtowski J, Rachańczyk J, Włodarczyk M. Thiazolidinedione-induced fluid retention: recent insights into the molecular mechanisms. PPAR Res 2013; 2013:628628. [PMID: 23577024 PMCID: PMC3614122 DOI: 10.1155/2013/628628] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 02/19/2013] [Indexed: 01/11/2023] Open
Abstract
Peroxisome proliferator-activated receptor- γ (PPAR γ ) agonists such as rosiglitazone and pioglitazone are used to improve insulin sensitivity in patients with diabetes mellitus. However, thiazolidinediones induce fluid retention, edema, and sometimes precipitate or exacerbate heart failure in a subset of patients. The mechanism through which thiazolidinediones induce fluid retention is controversial. Most studies suggest that this effect results from the increase in tubular sodium and water reabsorption in the kidney, but the role of specific nephron segments and sodium carriers involved is less clear. Some studies suggested that PPAR γ agonist stimulates Na(+) reabsorption in the collecting duct by activating epithelial Na(+) channel (ENaC), either directly or through serum and glucocorticoid-regulated kinase-1 (SGK-1). However, other studies did not confirm this mechanism and even report the suppression of ENaC. Alternative mechanisms in the collecting duct include stimulation of non-ENaC sodium channel or inhibition of chloride secretion to the tubular lumen. In addition, thiazolidinediones may augment sodium reabsorption in the proximal tubule by stimulating the expression and activity of apical Na(+)/H(+) exchanger-3 and basolateral Na(+)-HCO3 (-) cotransporter as well as of Na(+),K(+)-ATPase. These effects are mediated by PPAR γ -induced nongenomic transactivation of the epidermal growth factor receptor and downstream extracellular signal-regulated kinases (ERK).
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Affiliation(s)
- Jerzy Bełtowski
- Department of Pathophysiology, Medical University of Lublin, 8 Jaczewskiego, 20090 Lublin, Poland
| | - Jolanta Rachańczyk
- Department of Pathophysiology, Medical University of Lublin, 8 Jaczewskiego, 20090 Lublin, Poland
| | - Mirosław Włodarczyk
- Department of Pathophysiology, Medical University of Lublin, 8 Jaczewskiego, 20090 Lublin, Poland
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Moreira-Rodrigues M, Quelhas-Santos J, Roncon-Albuquerque R, Serrão P, Leite-Moreira A, Sampaio-Maia B, Pestana M. Blunted renal dopaminergic system in a mouse model of diet-induced obesity. Exp Biol Med (Maywood) 2012; 237:949-55. [DOI: 10.1258/ebm.2012.012077] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Obesity has reached epidemic proportions in the Western world and is implicated in the pathophysiology of essential hypertension. The aim of the present study was to evaluate sodium handling, blood pressure and renal dopaminergic system activity in a mouse model of obesity induced by exposure to a hypercaloric diet. From six to 18 weeks of age, animals were fed with a control diet or a high-fat high-simple-carbohydrate (HFHSC) diet. Renal function, blood pressure and urinary and plasmatic catecholamines and biochemical parameters were evaluated in both groups. In parallel, the effects of high sodium intake (HS, 1.0% NaCl, 3 days) on natriuresis, urinary catecholamine excretion and aromatic l-amino acid decarboxylase (AADC) activity were evaluated in control and obese mice. Mice exposed to the HFHSC diet presented obesity, hyperglycemia, glucose intolerance, insulin resistance, hyperinsulinemia and increased blood pressure. This was accompanied, in obese mice, by decreases in urinary excretion of dopamine and metabolites as well as reduced AADC activity in renal tissues. During HS intake, absolute urinary dopamine excretion increased in control, but not in obese mice. This was accompanied in obese mice by a natriuretic resistance on day 1 of the HS diet. In addition, obese mice presented increased urinary and plasmatic noradrenaline levels, as well as an increased heart rate when compared with control mice. In conclusion, in this model of diet-induced obesity hyperinsulinemia, insulin resistance and increased sympathetic tone are associated with blunted renal dopaminergic activity. It is suggested that this may contribute to compromised sodium excretion and increased blood pressure in obesity.
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Affiliation(s)
- Mónica Moreira-Rodrigues
- Nephrology Research and Development Unit, Faculty of Medicine
- Neuropharmacology, IBMC
- Department of Pharmacology and Therapeutics, Faculty of Medicine
| | | | | | - Paula Serrão
- Department of Pharmacology and Therapeutics, Faculty of Medicine
| | | | - Benedita Sampaio-Maia
- Nephrology Research and Development Unit, Faculty of Medicine
- Faculty of Dental Medicine, University of Porto, 4200 Porto
| | - Manuel Pestana
- Nephrology Research and Development Unit, Faculty of Medicine
- Department of Nephrology, Hospital S. João, 4200–319 Porto, Portugal
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Muhammad AB, Lokhandwala MF, Banday AA. Exercise reduces oxidative stress but does not alleviate hyperinsulinemia or renal dopamine D1 receptor dysfunction in obese rats. Am J Physiol Renal Physiol 2010; 300:F98-104. [PMID: 20926629 DOI: 10.1152/ajprenal.00386.2010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Impairment of renal dopamine D1 receptor (D1R)-mediated natriuresis is associated with hypertension in humans and animal models, including obese Zucker rats. We have previously reported that treatment of these rats with antioxidants or insulin sensitizers reduced insulin levels and oxidative stress, restored D1R-mediated natriuresis, and reduced blood pressure. Furthermore, the redox-sensitive transcription factor, nuclear factor-κB (NF-κB), has been implicated in impairment of D1R-mediated natriuresis during oxidative stress. In this study, we investigated the effect of exercise on insulin levels, oxidative stress, nuclear translocation of NF-κB, blood pressure, albuminuria, and D1R-mediated natriuresis. The exercise protocol involved treadmill exercise from 3 wk of age for 8 wk. Exercise reduced oxidative stress, nuclear translocation of NF-κB, and albuminuria. However, exercise did not reduce plasma insulin levels or blood pressure. Also, selective D1R agonist (SKF-38393)-mediated increases in sodium excretion and guanosine 5'-O-(3-thiotriphosphate) binding were impaired in obese rats compared with lean rats, and exercise did not restore this defect. We conclude that, while exercise is beneficial in reducing oxidative stress and renal injury, reducing insulin levels may be required to restore D1R-mediated natriuresis in this model of obesity and metabolic syndrome. Furthermore, this study supports previous observations that restoring D1R function contributes to blood pressure reduction in this model.
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Affiliation(s)
- Abdul Bari Muhammad
- Heart and Kidney Institute, College of Pharmacy, S & R-2 Bldg, University of Houston, 4800 Calhoun Rd., Houston, TX 77204, USA
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11
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Asghar M, Chugh G, Lokhandwala MF. Inflammation compromises renal dopamine D1 receptor function in rats. Am J Physiol Renal Physiol 2009; 297:F1543-9. [PMID: 19794106 DOI: 10.1152/ajprenal.00366.2009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We tested the effects of inflammation on renal dopamine D1 receptor signaling cascade, a key pathway that maintains sodium homeostasis and blood pressure during increased salt intake. Inflammation was produced by administering lipopolysaccharide (LPS; 4 mg/kg ip) to rats provided without (normal salt) and with 1% NaCl in drinking water for 2 wk (high salt). Control rats had saline injection and received tap water. We found that LPS increased the levels of inflammatory cytokines, interleukin-6, and tumor necrosis factor-alpha in the rats given either normal- or high-salt intake. Also, these rats had higher levels of oxidative stress markers, malondialdehyde and nitrotyrosine, and lower levels of antioxidant enzyme superoxide dismutase in the renal proximal tubules (RPTs). The nuclear levels of transcription factors NF-kappaB increased and Nrf2 decreased in the RPTs in response to LPS in rats given normal and high salt. Furthermore, D1 receptor numbers, D1 receptor proteins, and D1 receptor agonist (SKF38393)-mediated (35)S-GTPgammaS binding decreased in the RPTs in these rats. The basal activities of Na-K-ATPase in the RPTs were similar in control and LPS-treated rats given normal and high salt. SKF38393 caused inhibition of Na-K-ATPase activity in the primary cultures of RPTs treated with vehicle but not in the cultures treated with LPS. Furthermore, LPS caused an increase in blood pressure in the rats given high salt but not in the rats given normal salt. These results suggest that LPS differentially regulates NF-kappaB and Nrf2, produces inflammation, decreases antioxidant enzyme, increases oxidative stress, and causes D1 receptor dysfunction in the RPTs. The LPS-induced dysfunction of renal D1 receptors alters salt handling and causes hypertension in rats during salt overload.
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Affiliation(s)
- Mohammad Asghar
- Heart and Kidney Institute, College of Pharmacy, Univeristy of Houston, Houston, TX 77204, USA.
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12
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Dobrian AD. The complex role of PPARgamma in renal dysfunction in obesity: managing a Janus-faced receptor. Vascul Pharmacol 2006; 45:36-45. [PMID: 16716756 DOI: 10.1016/j.vph.2006.01.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2006] [Revised: 01/01/2006] [Accepted: 01/01/2006] [Indexed: 01/11/2023]
Abstract
Obesity is frequently accompanied by insulin resistance, type II diabetes, hypertension and atherosclerosis, a cluster of pathologies that are the major components of the metabolic syndrome. Obesity is a known cause for renal dysfunction that leads to two major renal pathologies: hypertension and glomerular and tubulointerstitial injury. Peroxizome proliferator activated receptors (PPARs) are transcription factors belonging to the nuclear hormone receptor superfamily with important functions in the regulation of metabolism. The role of PPARgamma isoforms in adipogenesis and vascular inflammation associated to obesity has been vastly studied and is well recognized, albeit not completely mechanistically understood. Also, the effect of various PPARgamma agonists on blood pressure reduction in different forms of hypertension, including obesity related hypertension has been reported, but the mechanisms involved are only beginning to be studied. Even less clear is the concurrent beneficial effect of PPARgamma agonists thiazolinendiones (TZD) on blood pressure reduction in different forms of hypertension and, at the same time, in some cases, the significant water retention leading to edema and heart failure. The occurrence of both these apparently opposite effects on the renal water and sodium handling suggests a complex role of PPARgamma in the kidney that is likely related to the metabolic state. Also, PPARgamma activation leads to a reduction in mesangial cell proliferation while stimulating apoptosis. TZD treatment reduces albuminuria in obese and diabetic humans and rodent models suggesting protective effects against renal tubuloglomerular injury. The focus of this review is to present and critically discuss the recent findings on the roles of PPARgamma in the kidney in direct relation to renal function and renal injury in obesity and obesity-initiated diabetes.
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Affiliation(s)
- Anca Dana Dobrian
- Department of Physiological Sciences, Eastern Virginia Medical School, 700W Olney Road, Lewis Hall, Room 2027, Norfolk, VA 23507, USA.
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Qayyum R, Adomaityte J. A meta-analysis of the effect of thiazolidinediones on blood pressure. J Clin Hypertens (Greenwich) 2006; 8:19-28. [PMID: 16407685 PMCID: PMC8109335 DOI: 10.1111/j.1524-6175.2005.04784.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In epidemiologic studies, insulin resistance is associated with hypertension. Thiazolidinediones (TZDs) are antidiabetic agents that decrease insulin resistance. Multiple clinical trials have evaluated the effect of TZDs on blood pressure (BP) with inconsistent results. The aim of this study was to estimate the effect of TZDs on BP. The authors searched PubMed for clinical trials published in English. A total of 37 clinical trials that reported a change in BP were included in the analysis. Trials with independent-group design and trials with pre-post design were evaluated separately. When compared with baseline, TZDs lowered systolic BP by 4.70 mm Hg (95% confidence interval, -6.13 to -3.27) and diastolic BP by 3.79 mm Hg (95% confidence interval, -5.82 to -1.77). When compared with placebo, TZDs lowered systolic BP by 3.47 mm Hg (95% confidence interval, -4.91 to -2.02) and diastolic BP by 1.84 mm Hg (95% confidence interval, -3.43 to -0.25). Thus, TZDs lower both systolic and diastolic BP, albeit the BP-lowering effect is small and may not be of clinical significance.
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Affiliation(s)
- Rehan Qayyum
- Prudich Medical Center, Montcalm, WV 24737, USA.
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14
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Asghar M, Banday AA, Fardoun RZ, Lokhandwala MF. Hydrogen peroxide causes uncoupling of dopamine D1-like receptors from G proteins via a mechanism involving protein kinase C and G-protein-coupled receptor kinase 2. Free Radic Biol Med 2006; 40:13-20. [PMID: 16337875 DOI: 10.1016/j.freeradbiomed.2005.08.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2004] [Revised: 08/08/2005] [Accepted: 08/08/2005] [Indexed: 02/07/2023]
Abstract
Dopamine, via activation of D1-like receptors, inhibits Na,K-ATPase and Na,H-exchanger in renal proximal tubules and promotes sodium excretion. This effect of dopamine is not seen in conditions associated with oxidative stress such as hypertension, diabetes, and aging due to uncoupling of D1-like receptors from G proteins. To identify the role of oxidative stress in uncoupling of the D1-like receptors, we utilized primary cultures from rat renal proximal tubules. Hydrogen peroxide (H2O2), an oxidant, treatment to the cell cultures increased the level of malondialdehyde, a marker of oxidative damage. Further, H2O2 decreased membranous D1-like receptor numbers and proteins, D1-like agonist (SKF 38393)-mediated [35S]GTPgammaS binding and SKF 38393-mediated inhibition of Na,K-ATPase. Moreover, H2O2 treatment to the cultures caused membranous translocation of G-protein-coupled receptor kinase 2 (GRK 2) and increased serine phosphorylation of D1A receptors accompanied by an increase in protein kinase C (PKC) activity. Interestingly, PKC inhibitors blocked the H2O2-mediated stimulation of GRK 2 and serine phosphorylation of D1A receptors. Further, GRK 2 antisense but not scrambled oligonucleotides attenuated the effect of H2O2 on membranous expression of GRK 2. Moreover, direct activation of PKC with phorbol ester (PMA) resulted in reduction of SKF 38393-mediated [35S]GTPgammaS binding. We conclude that H2O2 stimulates PKC leading to the activation of GRK 2, which causes serine phopshorylation of D1A receptors and receptor G-protein uncoupling in these cells, resulting in impairment in D1-like receptor function.
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Affiliation(s)
- Mohammad Asghar
- Heart and Kidney Institute, College of Pharmacy, University of Houston, Houston, TX 77204, USA
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15
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Zeng C, Sanada H, Watanabe H, Eisner GM, Felder RA, Jose PA. Functional genomics of the dopaminergic system in hypertension. Physiol Genomics 2005; 19:233-46. [PMID: 15548830 DOI: 10.1152/physiolgenomics.00127.2004] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Abnormalities in dopamine production and receptor function have been described in human essential hypertension and rodent models of genetic hypertension. Under normal conditions, D(1)-like receptors (D(1) and D(5)) inhibit sodium transport in the kidney and intestine. However, in the Dahl salt-sensitive and spontaneously hypertensive rats (SHRs) and in humans with essential hypertension, the D(1)-like receptor-mediated inhibition of epithelial sodium transport is impaired because of an uncoupling of the D(1)-like receptor from its G protein/effector complex. The uncoupling is receptor specific, organ selective, nephron-segment specific, precedes the onset of hypertension, and cosegregates with the hypertensive phenotype. The defective transduction of the renal dopaminergic signal is caused by activating variants of G protein-coupled receptor kinase type 4 (GRK4: R65L, A142V, A486V). The GRK4 locus is linked to and GRK4 gene variants are associated with human essential hypertension, especially in salt-sensitive hypertensive subjects. Indeed, the presence of three or more GRK4 variants impairs the natriuretic response to dopaminergic stimulation in humans. In genetically hypertensive rats, renal inhibition of GRK4 expression ameliorates the hypertension. In mice, overexpression of GRK4 variants causes hypertension either with or without salt sensitivity according to the variant. GRK4 gene variants, by preventing the natriuretic function of the dopaminergic system and by allowing the antinatriuretic factors (e.g., angiotensin II type 1 receptor) to predominate, may be responsible for salt sensitivity. Subclasses of hypertension may occur because of additional perturbations caused by variants of other genes, the quantitative interaction of which may vary depending upon the genetic background.
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Affiliation(s)
- Chunyu Zeng
- Department of Cardiology, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
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Chung BH, Li C, Sun BK, Lim SW, Ahn KO, Yang JH, Choi YH, Yoon KH, Sugawara A, Ito S, Kim J, Yang CW. Rosiglitazone protects against cyclosporine-induced pancreatic and renal injury in rats. Am J Transplant 2005; 5:1856-67. [PMID: 15996232 DOI: 10.1111/j.1600-6143.2005.00979.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Rosiglitazone (RGTZ) has protective effect against various types of injury. This study was performed to evaluate the effect of RGTZ on pancreatic and renal injury caused by cyclosporine (CsA). CsA (15 mg/kg) and RGTZ (3 mg/kg) were administered alone and together to the rats for 28 days. The effect of RGTZ on CsA-induced pancreatic injury was evaluated by intraperitoneal glucose tolerance test (IPGTT), plasma insulin concentrations and pancreatic beta-cell morphology. The effect of RGTZ on CsA-induced renal injury was evaluated by assessing renal function and pathology; mediators of inflammation and fibrosis such as angiotensin II (AngII), osteopontin (OPN) and transforming growth factor-beta1 (TGF-beta1) and apoptotic cell death. Four weeks of CsA treatment caused diabetes, renal dysfunction, typical pathologic lesions (arteriolopathy, interstitial fibrosis and inflammatory cells infiltration) and apoptotic cell death. RGTZ treatment decreased blood glucose concentration, increased plasma insulin concentration and preserved pancreatic beta islet mass. RGTZ treatment improved renal function and histopathology. Pro-inflammatory and pro-fibrotic molecules such as AngII, OPN and TGF-beta1, and apoptotic cell death also decreased with RGTZ treatment. These data suggest that RGTZ has a protective effect against CsA-induced pancreatic and renal injury.
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Affiliation(s)
- Byung Ha Chung
- Xenotransplantation Center, Department of Internal Medicine, The Catholic University of Korea, Seoul, South Korea
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Banday AA, Marwaha A, Tallam LS, Lokhandwala MF. Tempol reduces oxidative stress, improves insulin sensitivity, decreases renal dopamine D1 receptor hyperphosphorylation, and restores D1 receptor-G-protein coupling and function in obese Zucker rats. Diabetes 2005; 54:2219-26. [PMID: 15983225 DOI: 10.2337/diabetes.54.7.2219] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Oxidative stress plays a pathogenic role in hypertension, particularly the one associated with diabetes and obesity. Here, we test the hypothesis that renal dopamine D1 receptor dysfunction in obese Zucker rats is caused by oxidative stress. One group each from lean and obese Zucker rats received tempol, a superoxide dismutase mimetic in drinking water for 2 weeks. Obese animals were hypertensive, hyperglycemic, and hyperinsulinemic, exhibited renal oxidative stress, and increased protein kinase C activity. Also, there was hyperphosphorylation of D1 receptor, defective receptor-G-protein coupling, blunted dopamine-induced Na+-K+-ATPase inhibition, and diminished natriuretic response to D1 receptor agonist, SKF-38393. However, obese animals had elevated levels of plasma nitric oxide and urinary cGMP. In addition, L-N-nitroarginine and sodium nitroprusside showed similar effect on blood pressure in lean and obese rats. In obese animals, tempol reduced blood pressure, blood glucose, insulin, renal oxidative stress, and protein kinase C activity. Tempol also decreased D1 receptor phosphorylation and restored receptor G-protein coupling. Dopamine inhibited Na+-K+-ATPase activity, and SKF-38393 elicited a natriuretic response in tempol-treated obese rats. Thus in obese Zucker rats, tempol ameliorates oxidative stress and improves insulin sensitivity. Consequently, hyperphosphorylation of D1 receptor is reduced, leading to restoration of receptor-G-protein coupling and the natriuretic response to SKF-38393.
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Affiliation(s)
- Anees Ahmad Banday
- Heart and Kidney Institute, University of Houston, Houston, Texas 77204, USA
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Trivedi M, Lokhandwala MF. Rosiglitazone restores renal D1A receptor-Gs protein coupling by reducing receptor hyperphosphorylation in obese rats. Am J Physiol Renal Physiol 2005; 289:F298-304. [PMID: 15798088 DOI: 10.1152/ajprenal.00362.2004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Dopamine D(1A) receptor function is impaired in obesity-induced insulin resistance, contributing to sodium retention. We showed previously that uncoupling of D(1A) receptors from G proteins is responsible for diminished natriuretic response to dopamine in obese Zucker rats (OZRs). We hypothesized that overexpression of G protein-coupled receptor kinases (GRKs) leads to increased phosphorylation of D(1A) receptors, which in turn causes uncoupling of the receptors from G(s) proteins in proximal tubules of OZRs. We also examined effects of an insulin sensitizer, rosiglitazone, in correcting these defects. We found that basal and agonist (fenoldopam)-induced coupling of D(1A) receptors to G(s) proteins was impaired in proximal tubules of OZRs compared with lean Zucker rats (LZRs). Moreover, basal serine phosphorylation of D(1A) receptors was elevated two- to threefold in proximal tubules of OZRs compared with LZRs. Fenoldopam increased D(1A) receptor phosphorylation in proximal tubules of LZRs but not OZRs. Compared with that in LZRs, GRK4 expression in OZRs was elevated 200-300% in proximal tubule cell lysates and GRK2 expression was approximately 30% higher in plasma membranes isolated from proximal tubules of OZRs. Rosiglitazone treatment restored basal and agonist-induced coupling of D(1A) receptors to G(s) proteins and reduced basal serine phosphorylation of D(1A) receptors, GRK4 expression, and translocation of GRK2 to the plasma membrane in proximal tubules of OZRs. Furthermore, rosiglitazone significantly reduced fasting blood glucose and plasma insulin in OZRs. Collectively, these results suggest that insulin resistance is responsible for GRK4 overexpression and GRK2 translocation leading to hyperphosphorylation of D(1A) receptors and their uncoupling from G(s) proteins as rosiglitazone treatment corrects these defects in OZRs.
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Affiliation(s)
- Meghna Trivedi
- Heart and Kidney Institute, College of Pharmacy, University of Houston, TX 77204-5041, USA
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