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Lee HS, Kim HY, Ahn YM, Cho KW. Herbal medicine Oryeongsan (Wulingsan): Cardio-renal effects via modulation of renin-angiotensin system and atrial natriuretic peptide system. Integr Med Res 2024; 13:101066. [PMID: 39247397 PMCID: PMC11378099 DOI: 10.1016/j.imr.2024.101066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 06/06/2024] [Accepted: 06/20/2024] [Indexed: 09/10/2024] Open
Abstract
Background Oryeongsan (Wulingsan, Goreisan) has long been used for the treatment of impaired body fluid metabolism. However, the action mechanisms have not been clearly defined. Recently, effects of Oryeongsan on the body fluid and Na+ metabolism and the action mechanisms have been shown more clearly. The present review focuses on the recent findings on the effects of Oryeongsan in the cardio-renal system in relation with body fluid metabolism and action mechanisms leading to a decrease in blood pressure in animal models of hypertension. Methods The new and recent findings were searched by using searching systems including PubMed-NCBI and Google-Scholar. Results Oryeongsan induced an increase in glomerular filtration rate, and natriuresis and diuresis with a decreased osmolality and resulted in a contraction of the body fluid and Na+ balance. These findings were associated with a suppression of abundance of Na+-H +-exchanger isoform 3 expression and V2 receptor/aquaporin2 water channel signaling pathway in the kidney. Further, treatment with Oryeongsan accentuated atrial natriuretic peptide secretion in the atria from spontaneously hypertensive rats in which the secretion was suppressed. In addition, Oryeongsan ameliorated impaired vasodilation in spontaneously hypertensive rats. Conclusion The effects of Oryeongsan in the kidney, atria, and vessel were accompanied by a suppression of AT1 receptor and concurrent accentuation of abundance of AT2/Mas receptors expression and modulation of the natriuretic peptide system in these organs from hypertensive rats. The review shows multiple sites of action of Oryeongsan and mechanisms involved in the regulation of volume and pressure homeostasis in the body.
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Affiliation(s)
- Ho Sub Lee
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
- College of Korean Medicine and Professional Graduate School of Korean Medicine, Wonkwang University, Iksan, Republic of Korea
| | - Hye Yoom Kim
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
- College of Korean Medicine and Professional Graduate School of Korean Medicine, Wonkwang University, Iksan, Republic of Korea
| | - You Mee Ahn
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
- KM Science Research Division, Korea Institute of Oriental Medicine, Daejeon, Republic of Korea
| | - Kyung Woo Cho
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
- College of Korean Medicine and Professional Graduate School of Korean Medicine, Wonkwang University, Iksan, Republic of Korea
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Patel SN, Kulkarni K, Faisal T, Hussain T. Angiotensin-II type 2 receptor-mediated renoprotection is independent of receptor Mas in obese Zucker rats fed high-sodium diet. Front Pharmacol 2024; 15:1409313. [PMID: 39135807 PMCID: PMC11317439 DOI: 10.3389/fphar.2024.1409313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 06/27/2024] [Indexed: 08/15/2024] Open
Abstract
The consumption of a high-sodium diet (HSD) is injurious and known to elevate blood pressure (BP), especially in obesity. Acute infusion studies depict a functional interdependency between angiotensin-II type 2 receptor (AT2R) and receptor Mas (MasR). Hence, we hypothesize that the subacute blockade of MasR should reverse AT2R-mediated renoprotection in obese Zucker rats (OZRs). Male OZRs were fed an HSD (for 14 days) and treated with the AT2R agonist C21 (100 ng/min) without or with a MasR antagonist A779 (1,000 ng/min). The indices of oxidative stress, proteinuria, kidney injury, and BP were measured before and after, along with the terminal measurements of an array of inflammatory and kidney injury markers. The HSD significantly decreased the estimated glomerular filtration rate and urinary osmolality and increased thirst, diuresis, natriuresis, kaliuresis, plasma creatinine, urinary excretion of H2O2, proteinuria, renal expression and urinary excretion of kidney injury markers (NGAL and KIM-1), and BP indexes. The HSD feeding showed early changes in the renal expression of CRP, ICAM-1, and galectin-1. The C21 treatment prevented these pathological changes. The MasR antagonist A779 attenuated C21-mediated effects on the urinary excretion and renal expression of NGAL and oxidative stress in the absence of inflammation and BP changes. Overall, we conclude that the subacute functional interactions between AT2R and MasR are weak or transient and that the beneficial effects of AT2R activation are independent of the MasR blockade in the kidney of male obese rats fed an HSD.
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Affiliation(s)
| | | | | | - Tahir Hussain
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, United States
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Souza-Silva IM, Peluso AA, Elsaafien K, Nazarova AL, Assersen KB, Rodrigues-Ribeiro L, Mohammed M, Rodrigues AF, Nawrocki A, Jakobsen LA, Jensen P, de Kloet AD, Krause EG, Borgo MD, Maslov I, Widdop R, Santos RA, Bader M, Larsen M, Verano-Braga T, Katritch V, Sumners C, Steckelings UM. Angiotensin-(1-5) is a Potent Endogenous Angiotensin AT 2 -Receptor Agonist. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.05.588367. [PMID: 38948791 PMCID: PMC11213140 DOI: 10.1101/2024.04.05.588367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Background The renin-angiotensin system involves many more enzymes, receptors and biologically active peptides than originally thought. With this study, we investigated whether angiotensin-(1-5) [Ang-(1-5)], a 5-amino acid fragment of angiotensin II, has biological activity, and through which receptor it elicits effects. Methods The effect of Ang-(1-5) (1µM) on nitric oxide release was measured by DAF-FM staining in human aortic endothelial cells (HAEC), or Chinese Hamster Ovary (CHO) cells stably transfected with the angiotensin AT 2 -receptor (AT 2 R) or the receptor Mas. A potential vasodilatory effect of Ang-(1-5) was tested in mouse mesenteric and human renal arteries by wire myography; the effect on blood pressure was evaluated in normotensive C57BL/6 mice by Millar catheter. These experiments were performed in the presence or absence of a range of antagonists or inhibitors or in AT 2 R-knockout mice. Binding of Ang-(1-5) to the AT 2 R was confirmed and the preferred conformations determined by in silico docking simulations. The signaling network of Ang-(1-5) was mapped by quantitative phosphoproteomics. Results Key findings included: (1) Ang-(1-5) induced activation of eNOS by changes in phosphorylation at Ser1177 eNOS and Tyr657 eNOS and thereby (2) increased NO release from HAEC and AT 2 R-transfected CHO cells, but not from Mas-transfected or non-transfected CHO cells. (3) Ang-(1-5) induced relaxation of preconstricted mouse mesenteric and human renal arteries and (4) lowered blood pressure in normotensive mice - effects which were respectively absent in arteries from AT 2 R-KO or in PD123319-treated mice and which were more potent than effects of the established AT 2 R-agonist C21. (5) According to in silico modelling, Ang-(1-5) binds to the AT 2 R in two preferred conformations, one differing substantially from where the first five amino acids within angiotensin II bind to the AT 2 R. (6) Ang-(1-5) modifies signaling pathways in a protective RAS-typical way and with relevance for endothelial cell physiology and disease. Conclusions Ang-(1-5) is a potent, endogenous AT 2 R-agonist.
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Ahn YM, Kim HY, Kang DG, Cho KW, Lee HS. Herbal medicine (Oryeongsan) for fluid and sodium balance in renal cortex of spontaneously hypertensive rats. Integr Med Res 2024; 13:101007. [PMID: 38298863 PMCID: PMC10826321 DOI: 10.1016/j.imr.2023.101007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 11/02/2023] [Accepted: 11/13/2023] [Indexed: 02/02/2024] Open
Abstract
Background Herbal medicine Oryeongsan (ORS), also known as Wulingsan in Chinesehas been used for the treatment of impaired body fluid balance. However, the mechanisms involved are not clearly defined. The purpose of the present study was to identify the actions of ORS on the renal excretory function and blood pressure (BP) and to define the mechanisms involved in association with renin-angiotensin system (RAS) and natriuretic peptide system (NPS) in spontaneously hypertensive rats (SHR), an animal model of human essential hypertension. Methods Changes in urine volume (UV), excretion of electrolytes including Na+ (urinary excretion of Na+ (UNaV)) were measured. RT-PCR was performed to trace the changes in expression of RAS, NPS and sodium (Na+)-hydrogen (H+) exchanger 3 (NHE3) in the renal cortex. Results In the SHR treated with vehicle (SHR-V) group, UV and UNaV were suppressed and the Na+ balance was maintained at the higher levels leading to an increase in BP compared to WKY-V group. These were accompanied by an increase in NHE3 expression with an accentuation of angiotensin I converting enzyme-angiotensin II type 1 (ACE-AT1) receptor and concurrent suppression of angiotensin II type 2 (AT2) receptor/ACE2-Mas receptor expression in the renal cortex. Chronic treatment with ORS increased UV and UNaV, and decreased the Na+ and water balance with a decrease in BP in the ORS-treated SHR-ORS group compared to SHR-V. These were accompanied by a decrease in NHE3 expression with a suppression of ACE-AT1 receptor and concurrent accentuation of AT2/ACE2-Mas receptor. Conclusion The present study shows that ORS reduced BP with a decrease in Na+ and water retention by a suppression of NHE3 expression via modulation of RAS and NPS in SHR. The present study provides pharmacological rationale for the treatment of hypertension with ORS in SHR.
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Affiliation(s)
- You Mee Ahn
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
- KM Science Research Division, Korea Institute of Oriental Medicine, Daejeon, Republic of Korea
| | - Hye Yoom Kim
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
| | - Dae Gill Kang
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
- College of Korean Medicine and Professional Graduate School of Korean Medicine, Wonkwang University, Iksan, Republic of Korea
| | - Kyung Woo Cho
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
| | - Ho Sub Lee
- Hanbang Cardio-Renal Syndrome Research Center, Wonkwang University, Iksan, Republic of Korea
- College of Korean Medicine and Professional Graduate School of Korean Medicine, Wonkwang University, Iksan, Republic of Korea
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Kodama T, Otani K, Okada M, Yamawaki H. Eukaryotic elongation factor 2 kinase inhibitor, A484954 induced diuresis via nitric oxide production in spontaneously hypertensive rats. J Vet Med Sci 2023; 85:1314-1318. [PMID: 37853639 PMCID: PMC10788169 DOI: 10.1292/jvms.23-0306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 10/03/2023] [Indexed: 10/20/2023] Open
Abstract
Eukaryotic elongation factor 2 (eEF2) kinase (eEF2K) is a protein kinase that inactivates eEF2, a protein that mediates a peptidyl-tRNA translocation during an elongation step of protein synthesis. We have previously shown that eEF2K was involved in pathogenesis of essential and pulmonary hypertension. A484954 (7-amino-1-cyclopropyl-3-ethyl-2,4-dioxo-1,2,3,4-tetrahydropyrido[2,3-d] pyrimidine-6-carboxamide), a selective eEF2K inhibitor, is a membrane permeable small molecule. We have previously shown that A484954 lowered blood pressure and induced diuretic effects in spontaneously hypertensive rats (SHR) due to an increase in renal blood flow. Here we aimed to reveal mechanisms underlying the diuretic effects of A484954 in SHR. A484954-induced diuresis and increase in urinary Na+ excretion were inhibited by N (G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide (NO) synthase inhibitor. A484954 increased mRNA expression of angiotensin type 2 receptor (AT2R) and nuclear factor-erythroid 2-related factor 2 (Nrf2). In summary, we for the first time revealed that A484954 induces diuresis in SHR at least partly via the activation of NO/Nrf2/AT2R pathway.
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Affiliation(s)
- Tomoko Kodama
- Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori, Japan
| | - Kosuke Otani
- Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori, Japan
| | - Muneyoshi Okada
- Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori, Japan
| | - Hideyuki Yamawaki
- Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori, Japan
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Dangudubiyyam SV, Bosse B, Yadav P, Song R, Hofmann A, Mishra JS, Kumar S. Restoring Angiotensin Type 2 Receptor Function Reverses PFOS-Induced Vascular Hyper-Reactivity and Hypertension in Pregnancy. Int J Mol Sci 2023; 24:14180. [PMID: 37762482 PMCID: PMC10531530 DOI: 10.3390/ijms241814180] [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: 07/27/2023] [Revised: 09/07/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
Perfluorooctane sulfonic acid (PFOS) exposure during pregnancy induces hypertension with decreased vasodilatory angiotensin type-2 receptor (AT2R) expression and impaired vascular reactivity and fetal weights. We hypothesized that AT2R activation restores the AT1R/AT2R balance and reverses gestational hypertension by improving vascular mechanisms. Pregnant Sprague-Dawley rats were exposed to PFOS through drinking water (50 μg/mL) from gestation day (GD) 4-20. Controls received drinking water with no detectable PFOS. Control and PFOS-exposed rats were treated with AT2R agonist Compound 21 (C21; 0.3 mg/kg/day, SC) from GD 15-20. In PFOS dams, blood pressure was higher, blood flow in the uterine artery was reduced, and C21 reversed these to control levels. C21 mitigated the heightened contraction response to Ang II and enhanced endothelium-dependent vasorelaxation in uterine arteries of PFOS dams. The observed vascular effects of C21 were correlated with reduced AT1R levels and increased AT2R and eNOS protein levels. C21 also increased plasma bradykinin production in PFOS dams and attenuated the fetoplacental growth restriction. These data suggest that C21 improves the PFOS-induced maternal vascular dysfunction and blood flow to the fetoplacental unit, providing preclinical evidence to support that AT2R activation may be an important target for preventing or treating PFOS-induced adverse maternal and fetal outcomes.
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Affiliation(s)
- Sri Vidya Dangudubiyyam
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
- Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
| | - Bradley Bosse
- Department of Obstetrics and Gynecology, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53792, USA;
| | - Pankaj Yadav
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
| | - Ruolin Song
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
| | - Alissa Hofmann
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
- Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
| | - Jay S. Mishra
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
| | - Sathish Kumar
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
- Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
- Department of Obstetrics and Gynecology, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53792, USA;
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Li X, Zhuo J. Intracellular Angiotensin II Stimulation of Sodium Transporter Expression in Proximal Tubule Cells via AT 1 (AT 1a) Receptor-Mediated, MAP Kinases ERK1/2- and NF-кB-Dependent Signaling Pathways. Cells 2023; 12:1492. [PMID: 37296613 PMCID: PMC10252550 DOI: 10.3390/cells12111492] [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: 03/17/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
The current prevailing paradigm in the renin-angiotensin system dictates that most, if not all, biological, physiological, and pathological responses to its most potent peptide, angiotensin II (Ang II), are mediated by extracellular Ang II activating its cell surface receptors. Whether intracellular (or intracrine) Ang II and its receptors are involved remains incompletely understood. The present study tested the hypothesis that extracellular Ang II is taken up by the proximal tubules of the kidney by an AT1 (AT1a) receptor-dependent mechanism and that overexpression of an intracellular Ang II fusion protein (ECFP/Ang II) in mouse proximal tubule cells (mPTC) stimulates the expression of Na+/H+ exchanger 3 (NHE3), Na+/HCO3- cotransporter, and sodium and glucose cotransporter 2 (Sglt2) by AT1a/MAPK/ERK1/2/NF-kB signaling pathways. mPCT cells derived from male wild-type and type 1a Ang II receptor-deficient mice (Agtr1a-/-) were transfected with an intracellular enhanced cyan fluorescent protein-tagged Ang II fusion protein, ECFP/Ang II, and treated without or with AT1 receptor blocker losartan, AT2 receptor blocker PD123319, MEK1/MEK2 inhibitor U0126, NF-кB inhibitor RO 106-9920, or p38 MAP kinase inhibitor SB202196, respectively. In wild-type mPCT cells, the expression of ECFP/Ang II significantly increased NHE3, Na+/HCO3-, and Sglt2 expression (p < 0.01). These responses were accompanied by >3-fold increases in the expression of phospho-ERK1/2 and the p65 subunit of NF-кB (p < 0.01). Losartan, U0126, or RO 106-9920 all significantly attenuated ECFP/Ang II-induced NHE3 and Na+/HCO3- expression (p < 0.01). Deletion of AT1 (AT1a) receptors in mPCT cells attenuated ECFP/Ang II-induced NHE3 and Na+/HCO3- expression (p < 0.01). Interestingly, the AT2 receptor blocker PD123319 also attenuated ECFP/Ang II-induced NHE3 and Na+/HCO3- expression (p < 0.01). These results suggest that, similar to extracellular Ang II, intracellular Ang II may also play an important role in Ang II receptor-mediated proximal tubule NHE3, Na+/HCO3-, and Sglt2 expression by activation of AT1a/MAPK/ERK1/2/NF-kB signaling pathways.
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Affiliation(s)
- Xiaochun Li
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA;
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA
| | - Jialong Zhuo
- Tulane Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA;
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA
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Kulkarni K, Patel S, Ali R, Hussain T. Angiotensin II type 2 receptor activation preserves megalin in the kidney and prevents proteinuria in high salt diet fed rats. Sci Rep 2023; 13:4277. [PMID: 36922642 PMCID: PMC10017765 DOI: 10.1038/s41598-023-31454-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 03/12/2023] [Indexed: 03/18/2023] Open
Abstract
Proteinuria is a risk factor for and consequence of kidney injury. Angiotensin II type 2 receptor (AT2R) is an emerging reno-protective target and is anti-proteinuric under pathological conditions, including high salt-fed obese animals. However, the mechanisms remain unknown, particularly whether the anti-proteinuric activity of AT2R is independent of its anti-hypertensive and anti-inflammatory effects. In the present study, obese Zucker rats were fed high sodium (4%) diet (HSD) for 48 h, a time in which blood pressure does not change. HSD caused proteinuria without affecting glomerular slit diaphragm proteins (nephrin and podocin), glomerular filtration rate, inflammatory and fibrotic markers (TNFα, IL-6, and TGF-β), ruling out glomerular injury, inflammation and fibrosis but indicating tubular mechanisms of proteinuria. At cellular and molecular levels, we observed a glycogen synthase kinase (GSK)-3β-mediated megalin phosphorylation, and its subsequent endocytosis and lysosomal degradation in HSD-fed rat kidneys. Megalin is a major proximal tubular endocytic protein transporter. The AT2R agonist C21 (0.3 mg/kg/day, i.p.) administration prevented proteinuria and rescued megalin surface expression potentially by activating Akt-mediated phosphorylation and inactivation of GSK-3β in HSD-fed rat kidneys. Overall, AT2R has a direct anti-proteinuric activity, potentially via megalin regulation, and is suggested as a novel target to limit kidney injury.
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Affiliation(s)
- Kalyani Kulkarni
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health 2, 4349 Martin Luther King Boulevard, Houston, TX, 77204-5037, USA
| | - Sanket Patel
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health 2, 4349 Martin Luther King Boulevard, Houston, TX, 77204-5037, USA
| | - Riyasat Ali
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health 2, 4349 Martin Luther King Boulevard, Houston, TX, 77204-5037, USA
| | - Tahir Hussain
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health 2, 4349 Martin Luther King Boulevard, Houston, TX, 77204-5037, USA.
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Ma K, Zheng ZR, Meng Y. Pathogenesis of Chronic Kidney Disease Is Closely Bound up with Alzheimer's Disease, Especially via the Renin-Angiotensin System. J Clin Med 2023; 12:jcm12041459. [PMID: 36835994 PMCID: PMC9966558 DOI: 10.3390/jcm12041459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/01/2023] [Accepted: 02/07/2023] [Indexed: 02/15/2023] Open
Abstract
Chronic kidney disease (CKD) is a clinical syndrome secondary to the definitive change in function and structure of the kidney, which is characterized by its irreversibility and slow and progressive evolution. Alzheimer's disease (AD) is characterized by the extracellular accumulation of misfolded β-amyloid (Aβ) proteins into senile plaques and the formation of neurofibrillary tangles (NFTs) containing hyperphosphorylated tau. In the aging population, CKD and AD are growing problems. CKD patients are prone to cognitive decline and AD. However, the connection between CKD and AD is still unclear. In this review, we take the lead in showing that the development of the pathophysiology of CKD may also cause or exacerbate AD, especially the renin-angiotensin system (RAS). In vivo studies had already shown that the increased expression of angiotensin-converting enzyme (ACE) produces a positive effect in aggravating AD, but ACE inhibitors (ACEIs) have protective effects against AD. Among the possible association of risk factors in CKD and AD, we mainly discuss the RAS in the systemic circulation and the brain.
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Affiliation(s)
- Ke Ma
- The First Affiliated Hospital of Jinan University, Guangzhou 510000, China
| | - Zi-Run Zheng
- The First Affiliated Hospital of Jinan University, Guangzhou 510000, China
| | - Yu Meng
- The First Affiliated Hospital of Jinan University, Guangzhou 510000, China
- Central Laboratory, The Fifth Affiliated Hospital of Jinan University, Heyuan 517000, China
- Institute of Nephrology, Jinan University, Guangzhou 510000, China
- Correspondence:
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Characterization of the First Animal Toxin Acting as an Antagonist on AT1 Receptor. Int J Mol Sci 2023; 24:ijms24032330. [PMID: 36768653 PMCID: PMC9916866 DOI: 10.3390/ijms24032330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023] Open
Abstract
The renin-angiotensin system (RAS) is one of the main regulatory systems of cardiovascular homeostasis. It is mainly composed of angiotensin-converting enzyme (ACE) and angiotensin II receptors AT1 and AT2. ACE and AT1 are targets of choice for the treatment of hypertension, whereas the AT2 receptor is still not exploited due to the lack of knowledge of its physiological properties. Peptide toxins from venoms display multiple biological functions associated with varied chemical and structural properties. If Brazilian viper toxins have been described to inhibit ACE, no animal toxin is known to act on AT1/AT2 receptors. We screened a library of toxins on angiotensin II receptors with a radioligand competition binding assay. Functional characterization of the selected toxin was conducted by measuring second messenger production, G-protein activation and β-arrestin 2 recruitment using bioluminescence resonance energy transfer (BRET) based biosensors. We identified one original toxin, A-CTX-cMila, which is a 7-residues cyclic peptide from Conus miliaris with no homology sequence with known angiotensin peptides nor identified toxins, displaying a 100-fold selectivity for AT1 over AT2. This toxin shows a competitive antagonism mode of action on AT1, blocking Gαq, Gαi3, GαoA, β-arrestin 2 pathways and ERK1/2 activation. These results describe the first animal toxin active on angiotensin II receptors.
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He D, Ren H, Wang H, Jose PA, Zeng C, Xia T, Yang J. Effect of D4 Dopamine Receptor on Na+-K+-ATPase Activity in Renal Proximal Tubule Cells. CARDIOLOGY DISCOVERY 2022; 3:24-29. [PMID: 36969984 PMCID: PMC10030170 DOI: 10.1097/cd9.0000000000000076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 07/18/2022] [Indexed: 11/05/2022]
Abstract
Dopamine, via its receptors, plays a vital role in the maintenance of blood pressure by modulating renal sodium transport. However, the role of the D4 dopamine receptor (D4 receptor) in renal proximal tubules (PRTs) is still unclear. This study aimed to verify the hypothesis that activation of D4 receptor directly inhibits the activity of the Na+-K+-ATPase (NKA) in RPT cells. Methods NKA activity, nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) levels were measured in RPT cells treated with the D4 receptor agonist PD168077 and/or the D4 receptor antagonist L745870, the NO synthase inhibitor NG-nitro-L-arginine-methyl ester (L-NAME) or the soluble guanylyl cyclase inhibitor 1H-[1,2,4] oxadiazolo-[4,3-a] quinoxalin-1-one (ODQ). Total D4 receptor expression and its expression in the plasma membrane were investigated by immunoblotting in RPT cells from Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs). Results Activation of D4 receptors with PD168077, inhibited NKA activity in RPT cells from WKY rats in a concentration- and time-dependent manner. The inhibitory effect of PD168077 on NKA activity was prevented by the addition of the D4 receptor antagonist L745870, which by itself had no effect. The NO synthase inhibitor L-NAME and the soluble guanylyl cyclase inhibitor ODQ, which by themselves had no effect on NKA activity, eliminated the inhibitory effect of PD168077 on NKA activity. Activation of D4 receptors also increased NO levels in the culture medium and cGMP levels in RPT cells. However, the inhibitory effect of D4 receptors on NKA activity was absent in RPT cells from SHRs, which could be related to decreased plasma membrane expression of D4 receptors in SHR RPT cells. Conclusions Activation of D4 receptors directly inhibits NKA activity via the NO/cGMP signaling pathway in RPT cells from WKY rats but not SHRs. Aberrant regulation of NKA activity in RPT cells may be involved in the pathogenesis of hypertension.
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Endothelial and Vascular Smooth Muscle Dysfunction in Hypertension. Biochem Pharmacol 2022; 205:115263. [PMID: 36174768 DOI: 10.1016/j.bcp.2022.115263] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 12/11/2022]
Abstract
The development of essential hypertension involves several factors. Vascular dysfunction, characterized by endothelial dysfunction, low-grade inflammation and structural remodeling, plays an important role in the initiation and maintenance of essential hypertension. Although the mechanistic pathways by which essential hypertension develops are poorly understood, several pharmacological classes available on the clinical settings improve blood pressure by interfering in the cardiac output and/or vascular function. This review is divided in two major sections. The first section depicts the major molecular pathways as renin angiotensin aldosterone system (RAAS), endothelin, nitric oxide signalling pathway and oxidative stress in the development of vascular dysfunction. The second section describes the role of some pharmacological classes such as i) RAAS inhibitors, ii) dual angiotensin receptor-neprilysin inhibitors, iii) endothelin-1 receptor antagonists, iv) soluble guanylate cyclase modulators, v) phosphodiesterase type 5 inhibitors and vi) sodium-glucose cotransporter 2 inhibitors in the context of hypertension. Some classes are already approved in the treatment of hypertension, but others are not yet approved. However, due to their potential benefits these classes were included.
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Lin H, Geurts F, Hassler L, Batlle D, Mirabito Colafella KM, Denton KM, Zhuo JL, Li XC, Ramkumar N, Koizumi M, Matsusaka T, Nishiyama A, Hoogduijn MJ, Hoorn EJ, Danser AHJ. Kidney Angiotensin in Cardiovascular Disease: Formation and Drug Targeting. Pharmacol Rev 2022; 74:462-505. [PMID: 35710133 PMCID: PMC9553117 DOI: 10.1124/pharmrev.120.000236] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The concept of local formation of angiotensin II in the kidney has changed over the last 10-15 years. Local synthesis of angiotensinogen in the proximal tubule has been proposed, combined with prorenin synthesis in the collecting duct. Binding of prorenin via the so-called (pro)renin receptor has been introduced, as well as megalin-mediated uptake of filtered plasma-derived renin-angiotensin system (RAS) components. Moreover, angiotensin metabolites other than angiotensin II [notably angiotensin-(1-7)] exist, and angiotensins exert their effects via three different receptors, of which angiotensin II type 2 and Mas receptors are considered renoprotective, possibly in a sex-specific manner, whereas angiotensin II type 1 (AT1) receptors are believed to be deleterious. Additionally, internalized angiotensin II may stimulate intracellular receptors. Angiotensin-converting enzyme 2 (ACE2) not only generates angiotensin-(1-7) but also acts as coronavirus receptor. Multiple, if not all, cardiovascular diseases involve the kidney RAS, with renal AT1 receptors often being claimed to exert a crucial role. Urinary RAS component levels, depending on filtration, reabsorption, and local release, are believed to reflect renal RAS activity. Finally, both existing drugs (RAS inhibitors, cyclooxygenase inhibitors) and novel drugs (angiotensin receptor/neprilysin inhibitors, sodium-glucose cotransporter-2 inhibitors, soluble ACE2) affect renal angiotensin formation, thereby displaying cardiovascular efficacy. Particular in the case of the latter three, an important question is to what degree they induce renoprotection (e.g., in a renal RAS-dependent manner). This review provides a unifying view, explaining not only how kidney angiotensin formation occurs and how it is affected by drugs but also why drugs are renoprotective when altering the renal RAS. SIGNIFICANCE STATEMENT: Angiotensin formation in the kidney is widely accepted but little understood, and multiple, often contrasting concepts have been put forward over the last two decades. This paper offers a unifying view, simultaneously explaining how existing and novel drugs exert renoprotection by interfering with kidney angiotensin formation.
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Affiliation(s)
- Hui Lin
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Frank Geurts
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Luise Hassler
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Daniel Batlle
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Katrina M Mirabito Colafella
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Kate M Denton
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Jia L Zhuo
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Xiao C Li
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Nirupama Ramkumar
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Masahiro Koizumi
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Taiji Matsusaka
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Akira Nishiyama
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Martin J Hoogduijn
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Ewout J Hoorn
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - A H Jan Danser
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
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G-protein-coupled receptor kinase 4 causes renal angiotensin II type 2 receptor dysfunction by increasing its phosphorylation. Clin Sci (Lond) 2022; 136:989-1003. [PMID: 35695067 PMCID: PMC9793447 DOI: 10.1042/cs20220236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/01/2022] [Accepted: 06/13/2022] [Indexed: 12/30/2022]
Abstract
Activation of the angiotensin II type 2 receptor (AT2R) induces diuresis and natriuresis. Increased expression or/and activity of G-protein-coupled receptor kinase 4 (GRK4) or genetic variants (e.g., GRK4γ142V) cause sodium retention and hypertension. Whether GRK4 plays a role in the regulation of AT2R in the kidney remains unknown. In the present study, we found that spontaneously hypertensive rats (SHRs) had increased AT2R phosphorylation and impaired AT2R-mediated diuretic and natriuretic effects, as compared with normotensive Wistar-Kyoto (WKY) rats. The regulation by GRK4 of renal AT2R phosphorylation and function was studied in human (h) GRK4γ transgenic mice. hGRK4γ142V transgenic mice had increased renal AT2R phosphorylation and impaired AT2R-mediated natriuresis, relative to hGRK4γ wild-type (WT) littermates. These were confirmed in vitro; AT2R phosphorylation was increased and AT2R-mediated inhibition of Na+-K+-ATPase activity was decreased in hGRK4γ142V, relative to hGRK4γ WT-transfected renal proximal tubule (RPT) cells. There was a direct physical interaction between renal GRK4 and AT2R that was increased in SHRs, relative to WKY rats. Ultrasound-targeted microbubble destruction of renal GRK4 decreased the renal AT2R phosphorylation and restored the impaired AT2R-mediated diuresis and natriuresis in SHRs. In vitro studies showed that GRK4 siRNA reduced AT2R phosphorylation and reversed the impaired AT2R-mediated inhibition of Na+-K+-ATPase activity in SHR RPT cells. Our present study shows that GRK4, at least in part, impairs renal AT2R-mediated diuresis and natriuresis by increasing its phosphorylation; inhibition of GRK4 expression and/or activity may be a potential strategy to improve the renal function of AT2R.
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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.
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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,
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Advances in the Treatment Strategies in Hypertension: Present and Future. J Cardiovasc Dev Dis 2022; 9:jcdd9030072. [PMID: 35323620 PMCID: PMC8949859 DOI: 10.3390/jcdd9030072] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 02/27/2022] [Accepted: 03/01/2022] [Indexed: 12/11/2022] Open
Abstract
Hypertension is the most frequent chronic and non-communicable disease all over the world, with about 1.5 billion affected individuals worldwide. Its impact is currently growing, particularly in low-income countries. Even in high-income countries, hypertension remains largely underdiagnosed and undertreated, with consequent low rates of blood pressure (BP) control. Notwithstanding the large number of clinical observational studies and randomized trials over the past four decades, it is sad to note that in the last few years there has been an impressive paucity of innovative studies. Research focused on BP mechanisms and novel antihypertensive drugs is slowing dramatically. The present review discusses some advances in the management of hypertensive patients, and could play a clinical role in the years to come. First, digital/health technology is expected to be increasingly used, although some crucial points remain (development of non-intrusive and clinically validated devices for ambulatory BP measurement, robust storing systems enabling rapid analysis of accrued data, physician-patient interactions, etc.). Second, several areas should be better outlined with regard to BP diagnosis and treatment targets. Third, from a therapeutic standpoint, existing antihypertensive drugs, which are generally effective and well tolerated, should be better used by exploiting available and novel free and fixed combinations. In particular, spironolactone and other mineral-corticoid receptor antagonists should be used more frequently to improve BP control. In particular, some drugs initially developed for conditions different from hypertension including heart failure and diabetes have demonstrated to lower BP significantly and should therefore be considered. Finally, renal artery denervation is another procedure that has proven effective in the management of hypertension.
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Leite APDO, Li XC, Nwia SM, Hassan R, Zhuo JL. Angiotensin II and AT 1a Receptors in the Proximal Tubules of the Kidney: New Roles in Blood Pressure Control and Hypertension. Int J Mol Sci 2022; 23:2402. [PMID: 35269547 PMCID: PMC8910592 DOI: 10.3390/ijms23052402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 02/01/2023] Open
Abstract
Contrary to public perception, hypertension remains one of the most important public health problems in the United States, affecting 46% of adults with increased risk for heart attack, stroke, and kidney diseases. The mechanisms underlying poorly controlled hypertension remain incompletely understood. Recent development in the Cre/LoxP approach to study gain or loss of function of a particular gene has significantly helped advance our new insights into the role of proximal tubule angiotensin II (Ang II) and its AT1 (AT1a) receptors in basal blood pressure control and the development of Ang II-induced hypertension. This novel approach has provided us and others with an important tool to generate novel mouse models with proximal tubule-specific loss (deletion) or gain of the function (overexpression). The objective of this invited review article is to review and discuss recent findings using novel genetically modifying proximal tubule-specific mouse models. These new studies have consistently demonstrated that deletion of AT1 (AT1a) receptors or its direct downstream target Na+/H+ exchanger 3 (NHE3) selectively in the proximal tubules of the kidney lowers basal blood pressure, increases the pressure-natriuresis response, and induces natriuretic responses, whereas overexpression of an intracellular Ang II fusion protein or AT1 (AT1a) receptors selectively in the proximal tubules increases proximal tubule Na+ reabsorption, impairs the pressure-natriuresis response, and elevates blood pressure. Furthermore, the development of Ang II-induced hypertension by systemic Ang II infusion or by proximal tubule-specific overexpression of an intracellular Ang II fusion protein was attenuated in mutant mice with proximal tubule-specific deletion of AT1 (AT1a) receptors or NHE3. Thus, these recent studies provide evidence for and new insights into the important roles of intratubular Ang II via AT1 (AT1a) receptors and NHE3 in the proximal tubules in maintaining basal blood pressure homeostasis and the development of Ang II-induced hypertension.
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Affiliation(s)
- Ana Paula de Oliveira Leite
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Xiao C. Li
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Sarah M. Nwia
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Rumana Hassan
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Jia L. Zhuo
- Tulane Hypertension and Renal Center of Excellence, 1430 Tulane Avenue, New Orleans, LA 70112, USA; (A.P.d.O.L.); (X.C.L.); (S.M.N.); (R.H.)
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
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Angiotensin Type-2 Receptors: Transducers of Natriuresis in the Renal Proximal Tubule. Int J Mol Sci 2022; 23:ijms23042317. [PMID: 35216442 PMCID: PMC8877933 DOI: 10.3390/ijms23042317] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 12/18/2022] Open
Abstract
Angiotensin II (Ang II) type-2 receptors (AT2R) are expressed in the adult kidney, prominently in renal proximal tubule cells (RPTCs), and play an important role in opposing renal sodium (Na+) retention induced by Ang II stimulation of Ang II type-1 receptor (AT1R). Natriuresis induced by AT1R blockade is due at least in part to AT2R activation and whole body deletion of AT2Rs reduces the natriuretic response to increased blood pressure (BP). The major endogenous AT2R agonist mediating the natriuretic response is Ang III, the Ang II heptapeptide metabolite generated by aminopeptidase A, and the principal nephron site mediating inhibition of Na+ reabsorption by the AT2R is the renal proximal tubule (RPT). AT2Rs induce natriuresis via a bradykinin, nitric oxide and cyclic GMP (cGMP) signaling cascade. Recent studies demonstrated a key role for protein phosphatase 2A (PP2A) in the AT2R-mediated natriuretic response upstream of cGMP. By inducing natriuresis, AT2Rs lower BP in the Ang II-infusion model of hypertension. PP2A activation and the natriuretic response to AT2R stimulation are defective in spontaneously hypertensive rats, a model of primary hypertension in humans. AT2R agonists are candidates for proximal tubule natriuretic agents in Na+ and fluid retention disorders.
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Kemp BA, Howell NL, Gildea JJ, Keller SR, Brautigan DL, Carey RM. Renal AT 2 Receptors Mediate Natriuresis via Protein Phosphatase PP2A. Circ Res 2022; 130:96-111. [PMID: 34794320 PMCID: PMC8741733 DOI: 10.1161/circresaha.121.319519] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND How signals from activated angiotensin type-2 receptors (AT2R) mediate inhibition of sodium ion (Na+) reabsorption in renal proximal tubule cells is currently unknown. Protein phosphatases including PP2A (protein phosphatase 2A) have been implicated in AT2R signaling in tissues other than kidney. We investigated whether inhibition of protein phosphatase PP2A reduced AT2R-mediated natriuresis and evaluated changes in PP2A activity and localization after renal AT2R activation in normal 4- and 10-week-old control Wistar-Kyoto rats and 4-week-old prehypertensive and 10-week-old hypertensive spontaneously hypertensive rats. METHODS AND RESULTS In Wistar-Kyoto rats, direct renal interstitial administration of selective AT2R nonpeptide agonist Compound-21 (C-21) increased renal interstitial cyclic GMP (cGMP) levels, urine Na+ excretion, and simultaneously increased PP2A activity ≈2-fold in homogenates of renal cortical tubules. The cyclic GMP and natriuretic responses were abolished by concurrent renal interstitial administration of protein phosphatase inhibitor calyculin A. In renal proximal tubule cells in response to C-21, PP2A subunits A, B55α and C, but not B56γ, were recruited to apical plasma membranes together with AT2Rs. Calyculin A treatment abolished C-21-induced translocation of both AT2R and PP2A regulatory subunit B55α to apical plasma membranes. Immunoprecipitation of AT2R solubilized from renal cortical homogenates demonstrated physical association of AT2R with PP2A A, B55α, and C but not B56γ subunits. In contrast, in spontaneously hypertensive rats, administration of C-21 did not alter urine Na+ excretion or PP2A activity and failed to translocate AT2Rs and PP2A subunits to apical plasma membranes. CONCLUSIONS In renal proximal tubule cells of Wistar-Kyoto rats, PP2A is activated and PP2A subunits AB55αC are recruited to C-21-activated AT2Rs during induction of natriuresis. This response is defective in prehypertensive and hypertensive spontaneously hypertensive rats, presenting a potential novel therapeutic target for treating renal Na+ retention and hypertension.
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Affiliation(s)
- Brandon A. Kemp
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA
| | - Nancy L. Howell
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA
| | - John J. Gildea
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, VA
| | - Susanna R. Keller
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA
| | - David L. Brautigan
- Department of Microbiology, Immunology & Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA
| | - Robert M. Carey
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA
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Crosstalk between the renin-angiotensin, complement and kallikrein-kinin systems in inflammation. Nat Rev Immunol 2021; 22:411-428. [PMID: 34759348 PMCID: PMC8579187 DOI: 10.1038/s41577-021-00634-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2021] [Indexed: 12/28/2022]
Abstract
During severe inflammatory and infectious diseases, various mediators modulate the equilibrium of vascular tone, inflammation, coagulation and thrombosis. This Review describes the interactive roles of the renin–angiotensin system, the complement system, and the closely linked kallikrein–kinin and contact systems in cell biological functions such as vascular tone and leakage, inflammation, chemotaxis, thrombosis and cell proliferation. Specific attention is given to the role of these systems in systemic inflammation in the vasculature and tissues during hereditary angioedema, cardiovascular and renal glomerular disease, vasculitides and COVID-19. Moreover, we discuss the therapeutic implications of these complex interactions, given that modulation of one system may affect the other systems, with beneficial or deleterious consequences. The renin–angiotensin, complement and kallikrein–kinin systems comprise a multitude of mediators that modulate physiological responses during inflammatory and infectious diseases. This Review investigates the complex interactions between these systems and how these are dysregulated in various conditions, including cardiovascular diseases and COVID-19, as well as their therapeutic implications.
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21
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Renin-Angiotensin System Induced Secondary Hypertension: The Alteration of Kidney Function and Structure. Int J Nephrol 2021. [PMID: 31628476 PMCID: PMC8505109 DOI: 10.1155/2021/5599754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Long-term hypertension is known as a major risk factor for cardiovascular and chronic kidney disease (CKD). The Renin-angiotensin system (RAS) plays a key role in hypertension pathogenesis. Angiotensin II (Ang II) enhancement in Ang II-dependent hypertension leads to progressive CKD and kidney fibrosis. In the two-kidney one-clip model (2K1C), more renin is synthesized in the principal cells of the collecting duct than juxtaglomerular cells (JGCs). An increase of renal Ang I and Ang II levels and a decrease of renal cortical and medullary Ang 1–7 occur in both kidneys of the 2K1C hypertensive rat model. In addition, the activity of the angiotensin-converting enzyme (ACE) increases, while ACE2's activity decreases in the medullary region of both kidneys in the 2K1C hypertensive model. Also, the renal prolyl carboxypeptidase (PrCP) expression and its activity reduce in the clipped kidneys. The imbalance in the production of renal ACE, ACE2, and PrCP expression causes the progression of renal injury. Intrarenal angiotensinogen (AGT) expression and urine AGT (uAGT) excretion rates in the unclipped kidney are greater than the clipped kidney in the 2K1C hypertensive rat model. The enhancement of Ang II in the clipped kidney is related to renin secretion, while the elevation of intrarenal Ang II in the unclipped kidney is related to stimulation of AGT mRNA and protein in proximal tubule cells by a direct effect of systemic Ang II level. Ang II-dependent hypertension enhances macrophages and T-cell infiltration into the kidney which increases cytokines, and AGT synthesis in proximal tubules is stimulated via cytokines. Accumulation of inflammatory cells in the kidney aggravates hypertension and renal damage. Moreover, Ang II-dependent hypertension alters renal Ang II type 1 & 2 receptors (AT1R & AT2R) and Mas receptor (MasR) expression, and the renal interstitial fluid bradykinin, nitric oxide, and cGMP response to AT1R, AT2R, or BK B2-receptor antagonists. Based on a variety of sources including PubMed, Google Scholar, Scopus, and Science-Direct, in the current review, we will discuss the role of RAS-induced secondary hypertension on the alteration of renal function.
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22
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Yu J, Wang S, Shi W, Zhou W, Niu Y, Huang S, Zhang Y, Zhang A, Jia Z. Roxadustat (FG-4592) prevents Ang II hypertension by targeting angiotensin receptors and eNOS. JCI Insight 2021; 6:e133690. [PMID: 34403364 PMCID: PMC8492313 DOI: 10.1172/jci.insight.133690] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 08/11/2021] [Indexed: 11/28/2022] Open
Abstract
The prevalence of hypertension is increasing globally, while strategies for prevention and treatment of hypertension remain limited. FG-4592 (Roxadustat) is a potentially novel, orally active small-molecule hypoxia-inducible factor (HIF) stabilizer and is being used clinically to treat chronic kidney disease (CKD) anemia. In the present study, we evaluate the effects of FG-4592 on hypertension. In an angiotensin II (Ang II) hypertension model, FG-4592 abolished hypertensive responses; prevented vascular thickening, cardiac hypertrophy, and kidney injury; downregulated AGTR1 expression; and enhanced AGTR2, endothelial NO synthase (eNOS), and HIF1α protein levels in the aortas of mice. Additionally, the levels of thiobarbituric acid reactive substances (TBARs) in blood and urine were diminished by FG-4592 treatment. In vascular smooth muscle cells, FG-4592 treatment reduced angiotensin receptor type 1 (AGTR1) and increased AGTR2 levels, while preventing Ang II–induced oxidative stress. In vascular endothelial cells, FG-4592 upregulated total and phosphorylated eNOS. Moreover, FG-4592 treatment was hypotensive in L-NAME–induced hypertension. In summary, FG-4592 treatment remarkably ameliorated hypertension and organ injury, possibly through stabilizing HIF1α and subsequently targeting eNOS, AGTR1, AGTR2, and oxidative stress. Therefore, in addition to its role in treating CKD anemia, FG-4592 could be explored as a treatment for hypertension associated with high renin angiotensin system (RAS) activity or eNOS defects.
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Affiliation(s)
- Jing Yu
- Department of Nephrology, Nanjing Medical University, Nanjing, China
| | - Shuqin Wang
- Department of Nephrology, Nanjing Medical University, Nanjing, China
| | - Wei Shi
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Wei Zhou
- Department of Nephrology, Nanjing Medical University, Nanjing, China
| | - Yujia Niu
- Department of Nephrology, Nanjing Medical University, Nanjing, China
| | - Songming Huang
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Yue Zhang
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Aihua Zhang
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Zhanjun Jia
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
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23
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New Insights into the Critical Importance of Intratubular Na +/H + Exchanger 3 and Its Potential Therapeutic Implications in Hypertension. Curr Hypertens Rep 2021; 23:34. [PMID: 34110521 DOI: 10.1007/s11906-021-01152-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2021] [Indexed: 01/08/2023]
Abstract
PURPOSE OF REVIEW The sodium (Na+) and hydrogen (H+) exchanger 3 (NHE3), known as solute carrier family 9 member 3 (SLC9A3), mediates active transcellular Na+ and bicarbonate reabsorption in the small intestine of the gut and proximal tubules of the kidney. The purpose of this article is to review and discuss recent findings on the critical roles of intestinal and proximal tubule NHE3 in maintaining basal blood pressure (BP) homeostasis and their potential therapeutic implications in the development of angiotensin II (Ang II)-dependent hypertension. RECENT FINDINGS Recently, our and other laboratories have generated or used novel genetically modified mouse models with whole-body, kidney-specific, or proximal tubule-specific deletion of NHE3 to determine the critical roles and underlying mechanisms of NHE3 in maintaining basal BP homeostasis and the development of Ang II-induced hypertension at the whole-body, kidney, or proximal tubule levels. The new findings demonstrate that NHE3 contributes to about 10 to 15 mmHg to basal blood pressure levels, and that deletion of NHE3 at the whole-kidney or proximal tubule level, or pharmacological inhibition of NHE3 at the kidney level with an orally absorbable NHE3 inhibitor AVE-0657, attenuates ~ 50% of Ang II-induced hypertension in mice. The results support the proof-of-concept hypothesis that NHE3 plays critical roles in physiologically maintaining normal BP and in the development of Ang II-dependent hypertension. Our results also strongly suggest that NHE3 in the proximal tubules of the kidney may be therapeutically targeted to treat poorly controlled hypertension in humans.
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24
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Fatima N, Patel SN, Hussain T. Angiotensin II Type 2 Receptor: A Target for Protection Against Hypertension, Metabolic Dysfunction, and Organ Remodeling. Hypertension 2021; 77:1845-1856. [PMID: 33840201 PMCID: PMC8115429 DOI: 10.1161/hypertensionaha.120.11941] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The renin-angiotensin system is of vital significance not only in the maintenance of blood pressure but also because of its role in the pathophysiology of different organ systems in the body. Of the 2 Ang II (angiotensin II) receptors, the AT1R (Ang II type 1 receptor) has been extensively studied for its role in mediating the classical functions of Ang II, including vasoconstriction, stimulation of renal tubular sodium reabsorption, hormonal secretion, cell proliferation, inflammation, and oxidative stress. The other receptor, AT2R (Ang II type 2 receptor), is abundantly expressed in both immune and nonimmune cells in fetal tissue. However, its expression is increased under pathological conditions in adult tissues. The role of AT2R in counteracting AT1R function has been discussed in the past 2 decades. However, with the discovery of the nonpeptide agonist C21, the significance of AT2R in various pathologies such as obesity, hypertension, and kidney diseases have been examined. This review focuses on the most recent findings on the beneficial effects of AT2R by summarizing both gene knockout studies as well as pharmacological studies, specifically highlighting its importance in blood pressure regulation, obesity/metabolism, organ protection, and relevance in the treatment of coronavirus disease 2019 (COVID-19).
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Affiliation(s)
- Naureen Fatima
- From the Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, TX
| | - Sanket N Patel
- From the Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, TX
| | - Tahir Hussain
- From the Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, TX
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25
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Bovée DM, Ren L, Uijl E, Clahsen-van Groningen MC, van Veghel R, Garrelds IM, Domenig O, Poglitsch M, Zlatev I, Kim JB, Huang S, Melton L, Lu X, Hoorn EJ, Foster D, Danser AHJ. Renoprotective Effects of Small Interfering RNA Targeting Liver Angiotensinogen in Experimental Chronic Kidney Disease. Hypertension 2021; 77:1600-1612. [PMID: 33719507 DOI: 10.1161/hypertensionaha.120.16876] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Dominique M Bovée
- Division of Vascular Medicine and Pharmacology (D.M.B., L.R., E.U., R.v.V., I.M.G., A.H.J.D.), Erasmus MC, University Medical Center Rotterdam, the Netherlands.,Division of Nephrology and Transplantation, Department of Internal Medicine (D.M.B., E.U., E.J.H.), Erasmus MC, University Medical Center Rotterdam, the Netherlands
| | - Liwei Ren
- Division of Vascular Medicine and Pharmacology (D.M.B., L.R., E.U., R.v.V., I.M.G., A.H.J.D.), Erasmus MC, University Medical Center Rotterdam, the Netherlands.,Translational Medicine Collaborative Innovation Center, The Second Clinical Medical College (Shenzhen People's Hospital) of Jinan University, China (L.R.)
| | - Estrellita Uijl
- Division of Vascular Medicine and Pharmacology (D.M.B., L.R., E.U., R.v.V., I.M.G., A.H.J.D.), Erasmus MC, University Medical Center Rotterdam, the Netherlands.,Division of Nephrology and Transplantation, Department of Internal Medicine (D.M.B., E.U., E.J.H.), Erasmus MC, University Medical Center Rotterdam, the Netherlands
| | | | - Richard van Veghel
- Division of Vascular Medicine and Pharmacology (D.M.B., L.R., E.U., R.v.V., I.M.G., A.H.J.D.), Erasmus MC, University Medical Center Rotterdam, the Netherlands
| | - Ingrid M Garrelds
- Division of Vascular Medicine and Pharmacology (D.M.B., L.R., E.U., R.v.V., I.M.G., A.H.J.D.), Erasmus MC, University Medical Center Rotterdam, the Netherlands
| | | | | | - Ivan Zlatev
- Alnylam Pharmaceuticals, Cambridge, MA (I.Z., J.B.K., S.H., L.M., D.F.)
| | - Jae B Kim
- Alnylam Pharmaceuticals, Cambridge, MA (I.Z., J.B.K., S.H., L.M., D.F.)
| | - Stephen Huang
- Alnylam Pharmaceuticals, Cambridge, MA (I.Z., J.B.K., S.H., L.M., D.F.)
| | - Lauren Melton
- Alnylam Pharmaceuticals, Cambridge, MA (I.Z., J.B.K., S.H., L.M., D.F.)
| | - Xifeng Lu
- Department of Physiology, AstraZeneca-Shenzhen University Joint Institute of Nephrology, Shenzhen University Health Science Center, Shenzhen University, China (X.L.)
| | - Ewout J Hoorn
- Division of Nephrology and Transplantation, Department of Internal Medicine (D.M.B., E.U., E.J.H.), Erasmus MC, University Medical Center Rotterdam, the Netherlands
| | - Don Foster
- Alnylam Pharmaceuticals, Cambridge, MA (I.Z., J.B.K., S.H., L.M., D.F.)
| | - A H Jan Danser
- Division of Vascular Medicine and Pharmacology (D.M.B., L.R., E.U., R.v.V., I.M.G., A.H.J.D.), Erasmus MC, University Medical Center Rotterdam, the Netherlands
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Zhu H, Zhang L, Ma Y, Zhai M, Xia L, Liu J, Yu S, Duan W. The role of SARS-CoV-2 target ACE2 in cardiovascular diseases. J Cell Mol Med 2021; 25:1342-1349. [PMID: 33443816 PMCID: PMC7875924 DOI: 10.1111/jcmm.16239] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/03/2020] [Accepted: 12/14/2020] [Indexed: 12/24/2022] Open
Abstract
SARS-CoV-2, the virus responsible for the global coronavirus disease (COVID-19) pandemic, attacks multiple organs of the human body by binding to angiotensin-converting enzyme 2 (ACE2) to enter cells. More than 20 million people have already been infected by the virus. ACE2 is not only a functional receptor of COVID-19 but also an important endogenous antagonist of the renin-angiotensin system (RAS). A large number of studies have shown that ACE2 can reverse myocardial injury in various cardiovascular diseases (CVDs) as well as is exert anti-inflammatory, antioxidant, anti-apoptotic and anticardiomyocyte fibrosis effects by regulating transforming growth factor beta, mitogen-activated protein kinases, calcium ions in cells and other major pathways. The ACE2/angiotensin-(1-7)/Mas receptor axis plays a decisive role in the cardiovascular system to combat the negative effects of the ACE/angiotensin II/angiotensin II type 1 receptor axis. However, the underlying mechanism of ACE2 in cardiac protection remains unclear. Some approaches for enhancing ACE2 expression in CVDs have been suggested, which may provide targets for the development of novel clinical therapies. In this review, we aimed to identify and summarize the role of ACE2 in CVDs.
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Affiliation(s)
- Hanzhao Zhu
- Department of Cardiovascular SurgeryThe First Affiliated HospitalThe Air Force Medical UniversityXi’anChina
| | - Liyun Zhang
- Department of Cardiovascular SurgeryThe First Affiliated HospitalThe Air Force Medical UniversityXi’anChina
| | - Yubo Ma
- Department of Dermatology and VenereologyPeking University First HospitaBeijingChina
| | - Mengen Zhai
- Department of Cardiovascular SurgeryThe First Affiliated HospitalThe Air Force Medical UniversityXi’anChina
| | - Lin Xia
- Department of Cardiovascular SurgeryThe First Affiliated HospitalThe Air Force Medical UniversityXi’anChina
| | - Jincheng Liu
- Department of Cardiovascular SurgeryThe First Affiliated HospitalThe Air Force Medical UniversityXi’anChina
| | - Shiqiang Yu
- Department of Cardiovascular SurgeryThe First Affiliated HospitalThe Air Force Medical UniversityXi’anChina
| | - Weixun Duan
- Department of Cardiovascular SurgeryThe First Affiliated HospitalThe Air Force Medical UniversityXi’anChina
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27
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Novel therapeutics for the treatment of hypertension and its associated complications: peptide- and nonpeptide-based strategies. Hypertens Res 2021; 44:740-755. [PMID: 33731923 PMCID: PMC7967108 DOI: 10.1038/s41440-021-00643-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/08/2020] [Accepted: 01/20/2021] [Indexed: 01/31/2023]
Abstract
The renin-angiotensin-aldosterone system (RAAS) is responsible for maintaining blood pressure and vascular tone. Modulation of the RAAS, therefore, interferes with essential cellular processes and leads to high blood pressure, oxidative stress, inflammation, fibrosis, and hypertrophy. Consequently, these conditions cause fatal cardiovascular and renal complications. Thus, the primary purpose of hypertension treatment is to diminish or inhibit overactivated RAAS. Currently available RAAS inhibitors have proven effective in reducing blood pressure; however, beyond hypertension, they have failed to treat end-target organ injury. In addition, RAAS inhibitors have some intolerable adverse effects, such as hyperkalemia and hypotension. These gaps in the available treatment for hypertension require further investigation of the development of safe and effective therapies. Current research is focused on the combination of existing and novel treatments that neutralize the angiotensin II type I (AT1) receptor-mediated action of the angiotensin II peptide. Preclinical studies of peptide- and nonpeptide-based therapeutic agents demonstrate their conspicuous impact on the treatment of cardiovascular diseases in animal models. In this review, we will discuss novel therapeutic agents being developed as RAAS inhibitors that show prominent effects in both preclinical and clinical studies. In addition, we will also highlight the need for improvement in the efficacy of existing drugs in the absence of new prominent antihypertensive drugs.
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28
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Pulakat L, Sumners C. Angiotensin Type 2 Receptors: Painful, or Not? Front Pharmacol 2020; 11:571994. [PMID: 33424587 PMCID: PMC7785813 DOI: 10.3389/fphar.2020.571994] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 11/25/2020] [Indexed: 12/14/2022] Open
Abstract
Pain in response to various types of acute injury can be a protective stimulus to prevent the organism from using the injured part and allow tissue repair and healing. On the other hand, neuropathic pain, defined as ‘pain caused by a lesion or disease of the somatosensory nervous system’, is a debilitating pathology. The TRPA1 neurons in the Dorsal Root Ganglion (DRG) respond to reactive oxygen species (ROS) and induce pain. In acute nerve injury and inflammation, macrophages infiltrating the site of injury undergo an oxidative burst, and generate ROS that promote tissue repair and induce pain via TRPA1. The latter discourages using the injured limb, with a lack of movement helping wound healing. In chronic inflammation caused by diabetes, cancer etc., ROS levels increase systemically and modulate TRPA1 neuronal functions and cause debilitating neuropathic pain. It is important to distinguish between drug targets that elicit protective vs. debilitating pain when developing effective drugs for neuropathic pain. In this context, the connection of the Angiotensin type 2 receptor (AT2R) to neuropathic pain presents an interesting dilemma. Several lines of evidence show that AT2R activation promotes anti-inflammatory and anti-nociceptive signaling, tissue repair, and suppresses ROS in chronic inflammatory models. Conversely, some studies suggest that AT2R antagonists are anti-nociceptive and therefore AT2R is a drug target for neuropathic pain. However, AT2R expression in nociceptive neurons is lacking, indicating that neuronal AT2R is not involved in neuropathic pain. It is also important to consider that Novartis terminated their phase II clinical trial (EMPHENE) to validate that AT2R antagonist EMA401 mitigates post-herpetic neuralgia. This trial, conducted in Australia, United Kingdom, and a number of European and Asian countries in 2019, was discontinued due to pre-clinical drug toxicity data. Moreover, early data from the trial did not show statistically significant positive outcomes. These facts suggest that may AT2R not be the proper drug target for neuropathic pain in humans and its inhibition can be harmful.
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Affiliation(s)
- Lakshmi Pulakat
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA, United States.,Department of Medicine, Tufts University School of Medicine, Boston, MA, United States
| | - Colin Sumners
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL, United States
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Chaudhary M. Anti-Hypertensive Potential and Epigenetics of Angiotensin II type 2 Receptor (AT2R). Curr Hypertens Rev 2020; 17:176-180. [PMID: 33302839 DOI: 10.2174/1573402116999201209203015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/29/2020] [Accepted: 10/07/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Renin angiotensin system (RAS) is a critical pathway involved in blood pressure regulation. Octapeptide, angiotensin II (Ang II), is a biologically active compound of RAS pathway which mediates its action by binding to either angiotensin II type 1 receptor (AT1R) or angiotensin II type 2 receptor (AT2R). Binding of Ang II to AT1R facilitates blood pressure regulation, whereas AT2R is primarily involved in wound healing and tissue remodeling. OBJECTIVES Recent studies have highlighted the additional role of AT2R to counterbalance the detrimental effects of AT1R. Activation of angiotensin II type 2 receptor using AT2R agonist has shown the effect on natriuresis and release of nitric oxide. Additionally, AT2R activation has been found to inhibit angiotensin converting enzyme (ACE) and enhance angiotensin receptor blocker (ARB) activity. These findings highlight the potential of AT2R as a novel therapeutic target against hypertension. CONCLUSION The potential role of AT2R highlights the importance of exploring additional mechanisms that might be crucial for AT2R expression. Epigenetic mechanisms, including DNA methylation and histone modification, have been explored vastly with relation to cancer, but the role of such mechanisms in the expression of AT2R has recently gained interest.
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Affiliation(s)
- Mayank Chaudhary
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala-133207, Haryana, India
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30
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New drug targets for hypertension: A literature review. Biochim Biophys Acta Mol Basis Dis 2020; 1867:166037. [PMID: 33309796 DOI: 10.1016/j.bbadis.2020.166037] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 02/06/2023]
Abstract
Hypertension is one of the most prevalent cardiovascular diseases worldwide. However, in the population of resistant hypertension, blood pressure is difficult to control effectively. Moreover, antihypertensive drugs may have adverse effect currently. Hence, new therapeutic targets and treatments are needed to uncovered and exploited to control hypertension and its comorbidities. In the past, classical drug targets, such as the aldosterone receptor, aldosterone synthase, and ACE2/angiotensin 1-7/Mas receptor axis, have been investigated. Recently, vaccines and drugs targeting the gastrointestinal microbiome, which represent drug classes, have also been investigated for the management of blood pressure. In this review, we summarized current knowledge on classical and new drug targets and discussed the potential utility of new drugs in the treatment of hypertension.
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Patel SN, Fatima N, Ali R, Hussain T. Emerging Role of Angiotensin AT2 Receptor in Anti-Inflammation: An Update. Curr Pharm Des 2020; 26:492-500. [PMID: 31939729 DOI: 10.2174/1381612826666200115092015] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 11/21/2019] [Indexed: 12/16/2022]
Abstract
The hyperactive RAS and inflammation are closely associated. The angiotensin-II/AT1R axis of the RAS has been explored extensively for its role in inflammation and a plethora of pathological conditions. Understanding the role of AT2R in inflammation is an emerging area of research. The AT2R is expressed on a variety of immune and non-immune cells, which upon activation triggers the release of a host of cytokines and has multiple effects that coalesce to anti-inflammation and prevents maladaptive repair. The anti-inflammatory outcomes of AT2R activation are linked to its well-established signaling pathways involving formation of nitric oxide and activation of phosphatases. Collectively, these effects promote cell survival and tissue function. The consideration of AT2R as a therapeutic target requires further investigations.
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Affiliation(s)
- Sanket N Patel
- Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204, United States
| | - Naureen Fatima
- Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204, United States
| | - Riyasat Ali
- Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204, United States
| | - Tahir Hussain
- Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204, United States
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32
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Kemp BA, Howell NL, Keller SR, Gildea JJ, Shao W, Navar LG, Carey RM. Defective Renal Angiotensin III and AT 2 Receptor Signaling in Prehypertensive Spontaneously Hypertensive Rats. J Am Heart Assoc 2020; 8:e012016. [PMID: 31039659 PMCID: PMC6512109 DOI: 10.1161/jaha.119.012016] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Background Previous studies demonstrated that angiotensin (Ang) III, not Ang II, is the predominant endogenous agonist for Ang type‐2 receptor (AT2R)‐induced natriuresis in normal rats, and that hypertensive 12‐week‐old spontaneously hypertensive rats (SHR) lack natriuretic responses to Ang III. This study tested whether prehypertensive SHR already have defective Ang III‐induced natriuresis and determined possible mechanisms. Methods and Results Female and male normotensive 4‐week‐old SHR and Wistar Kyoto rats were studied after 24‐hour systemic AT1R blockade. Left kidneys received 30 minute renal interstitial infusions of vehicle followed by Ang III (3.5, 7.0, 14, and 28 nmol/kg per min; each dose for 30 minutes). Right kidneys received vehicle infusions. In 4‐week‐old Wistar Kyoto rats, renal interstitial Ang III increased urine sodium (Na+) excretion but failed to induce natriuresis in 4‐week‐old SHR. Renal Ang III levels were similar between Wistar Kyoto rats and SHR, making increased Ang III degradation as a possible cause for defective natriuresis in SHR unlikely. In Wistar Kyoto rats, renal interstitial Ang III induced translocation of AT2Rs to apical plasma membranes of renal proximal tubule cells. Simultaneously, Ang III induced retraction of the major Na+ transporter Na+‐H+ exchanger‐3 (NHE‐3) from apical membranes and internalization of Na+/K+ATPase (NKA) from basolateral membranes of renal proximal tubule cells. Consistent with NHE‐3 and NKA retraction, Ang III increased pSer552‐NHE‐3 and decreased pSer23‐NKA. In contrast, in SHR, intrarenal Ang III failed to induce AT2R translocation, NHE‐3 or NKA retraction, pSer552‐NHE‐3 phosphorylation, or pSer23‐NKA dephosphorylation. Conclusions These results indicate impaired Ang III/AT2R signaling as a possible primary defect in prehypertensive SHR. See Editorial Zhuo and Li
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Affiliation(s)
- Brandon A Kemp
- 1 Division of Endocrinology and Metabolism Department of Medicine University of Virginia School of Medicine Charlottesville VA
| | - Nancy L Howell
- 1 Division of Endocrinology and Metabolism Department of Medicine University of Virginia School of Medicine Charlottesville VA
| | - Susanna R Keller
- 1 Division of Endocrinology and Metabolism Department of Medicine University of Virginia School of Medicine Charlottesville VA
| | - John J Gildea
- 2 Department of Pathology University of Virginia School of Medicine Charlottesville VA
| | - Weijian Shao
- 3 Department of Physiology and Hypertension and Renal Center Tulane University School of Medicine New Orleans LA
| | - Luis Gabriel Navar
- 3 Department of Physiology and Hypertension and Renal Center Tulane University School of Medicine New Orleans LA
| | - Robert M Carey
- 1 Division of Endocrinology and Metabolism Department of Medicine University of Virginia School of Medicine Charlottesville VA
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Renal functional effects of the highly selective AT2R agonist, β-Pro7 Ang III, in normotensive rats. Clin Sci (Lond) 2020; 134:871-884. [PMID: 32202299 PMCID: PMC7158249 DOI: 10.1042/cs20200153] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/19/2020] [Accepted: 03/23/2020] [Indexed: 01/11/2023]
Abstract
Recently, we designed a group of peptides by sequential substitution of the naturally occurring α-amino acid throughout the Ang III peptide sequence with the corresponding β-amino acid. β-Amino acid substitution at the proline residue of Ang III (β-Pro7-Ang III) resulted in a highly selective AT2R ligand, demonstrating remarkable selectivity for the AT2R in both binding and functional studies. To provide additional functional evidence for the suitability of β-Pro7 Ang III as a novel AT2R agonist, we tested effects of acute systemic administration of β-Pro7-Ang III on renal hemodynamic and excretory function in anesthetized normotensive male and female rats. We also compared the natriuretic effects of acute intrarenal administration of native Ang III and β-Pro7-Ang III in the presence of systemic AT1R blockade in anesthetized female rats to allow for the differentiation of systemic versus direct intrarenal natriuretic actions of β-Pro7-Ang III. In both male and female rats, acute systemic administration of β-Pro7-Ang III elicited renal vasodilatation and natriuresis. Notably, greater renal vasodilatory effects were observed in female versus male rats at the highest dose of β-Pro7-Ang III administered. Moreover, intra-renal administration of β-Pro7-Ang III produced significant natriuretic effects in female rats and, like Ang III, evoked AT2R translocation to the apical plasma membrane in renal proximal tubular cells. Taken together, our findings support the use of β-Pro7-Ang III as a novel AT2R agonist and experimental tool for exploring AT2R function and its potential as a therapeutic target. Furthermore, our findings provide further evidence of a sex-specific influence of AT2R stimulation on renal function.
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Saikia S, Bordoloi M, Sarmah R. Established and In-trial GPCR Families in Clinical Trials: A Review for Target Selection. Curr Drug Targets 2020; 20:522-539. [PMID: 30394207 DOI: 10.2174/1389450120666181105152439] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/28/2018] [Accepted: 10/22/2018] [Indexed: 12/14/2022]
Abstract
The largest family of drug targets in clinical trials constitute of GPCRs (G-protein coupled receptors) which accounts for about 34% of FDA (Food and Drug Administration) approved drugs acting on 108 unique GPCRs. Factors such as readily identifiable conserved motif in structures, 127 orphan GPCRs despite various de-orphaning techniques, directed functional antibodies for validation as drug targets, etc. has widened their therapeutic windows. The availability of 44 crystal structures of unique receptors, unexplored non-olfactory GPCRs (encoded by 50% of the human genome) and 205 ligand receptor complexes now present a strong foundation for structure-based drug discovery and design. The growing impact of polypharmacology for complex diseases like schizophrenia, cancer etc. warrants the need for novel targets and considering the undiscriminating and selectivity of GPCRs, they can fulfill this purpose. Again, natural genetic variations within the human genome sometimes delude the therapeutic expectations of some drugs, resulting in medication response differences and ADRs (adverse drug reactions). Around ~30 billion US dollars are dumped annually for poor accounting of ADRs in the US alone. To curb such undesirable reactions, the knowledge of established and currently in clinical trials GPCRs families can offer huge understanding towards the drug designing prospects including "off-target" effects reducing economical resource and time. The druggability of GPCR protein families and critical roles played by them in complex diseases are explained. Class A, class B1, class C and class F are generally established family and GPCRs in phase I (19%), phase II(29%), phase III(52%) studies are also reviewed. From the phase I studies, frizzled receptors accounted for the highest in trial targets, neuropeptides in phase II and melanocortin in phase III studies. Also, the bioapplications for nanoparticles along with future prospects for both nanomedicine and GPCR drug industry are discussed. Further, the use of computational techniques and methods employed for different target validations are also reviewed along with their future potential for the GPCR based drug discovery.
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Affiliation(s)
- Surovi Saikia
- Natural Products Chemistry Group, CSIR North East Institute of Science & Technology, Jorhat-785006, Assam, India
| | - Manobjyoti Bordoloi
- Natural Products Chemistry Group, CSIR North East Institute of Science & Technology, Jorhat-785006, Assam, India
| | - Rajeev Sarmah
- Allied Health Sciences, Assam Down Town University, Panikhaiti, Guwahati 781026, Assam, India
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Li XC, Zhou X, Zhuo JL. Evidence for a Physiological Mitochondrial Angiotensin II System in the Kidney Proximal Tubules: Novel Roles of Mitochondrial Ang II/AT 1a/O 2- and Ang II/AT 2/NO Signaling. Hypertension 2020; 76:121-132. [PMID: 32475319 DOI: 10.1161/hypertensionaha.119.13942] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The present study tested the hypotheses that overexpression of an intracellular Ang II (angiotensin II) fusion protein, mito-ECFP/Ang II, selectively in the mitochondria of mouse proximal tubule cells induces mitochondrial oxidative and glycolytic responses and elevates blood pressure via the Ang II/AT1a receptor/superoxide/NHE3 (the Na+/H+ exchanger 3)-dependent mechanisms. A PT-selective, mitochondria-targeting adenoviral construct encoding Ad-sglt2-mito-ECFP/Ang II was used to test the hypotheses. The expression of mito-ECFP/Ang II was colocalized primarily with Mito-Tracker Red FM in mouse PT cells or with TMRM in kidney PTs. Mito-ECFP/Ang II markedly increased oxygen consumption rate as an index of mitochondrial oxidative response (69.5%; P<0.01) and extracellular acidification rate as an index of mitochondrial glycolytic response (34%; P<0.01). The mito-ECFP/Ang II-induced oxygen consumption rate and extracellular acidification rate responses were blocked by AT1 blocker losartan (P<0.01) and a mitochondria-targeting superoxide scavenger mito-TEMPO (P<0.01). By contrast, the nonselective NO inhibitor L-NAME alone increased, whereas the mitochondria-targeting expression of AT2 receptors (mito-AT2/GFP) attenuated the effects of mito-ECFP/Ang II (P<0.01). In the kidney, overexpression of mito-ECFP/Ang II in the mitochondria of the PTs increased systolic blood pressure 12±3 mm Hg (P<0.01), and the response was attenuated in PT-specific PT-Agtr1a-/- and PT-Nhe3-/- mice (P<0.01). Conversely, overexpression of AT2 receptors selectively in the mitochondria of the PTs induced natriuretic responses in PT-Agtr1a-/- and PT-Nhe3-/- mice (P<0.01). Taken together, these results provide new evidence for a physiological role of PT mitochondrial Ang II/AT1a/superoxide/NHE3 and Ang II/AT2/NO/NHE3 signaling pathways in maintaining blood pressure homeostasis.
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Affiliation(s)
- Xiao Chun Li
- From the Tulane Hypertension and Renal Center of Excellence (X.C.L., J.L.Z.), Tulane University School of Medicine, New Orleans, LA.,Department of Physiology (X.C.L., J.L.Z.), Tulane University School of Medicine, New Orleans, LA.,Department of Pharmacology and Toxicology (X.C.L., J.L.Z.), University of Mississippi Medical Center, Jackson
| | - Xinchun Zhou
- Department of Pathology (X.Z.), University of Mississippi Medical Center, Jackson
| | - Jia Long Zhuo
- From the Tulane Hypertension and Renal Center of Excellence (X.C.L., J.L.Z.), Tulane University School of Medicine, New Orleans, LA.,Department of Physiology (X.C.L., J.L.Z.), Tulane University School of Medicine, New Orleans, LA.,Department of Pharmacology and Toxicology (X.C.L., J.L.Z.), University of Mississippi Medical Center, Jackson
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36
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Sharma N, Belenchia AM, Toedebusch R, Pulakat L, Hans CP. AT2R agonist NP-6A4 mitigates aortic stiffness and proteolytic activity in mouse model of aneurysm. J Cell Mol Med 2020; 24:7393-7404. [PMID: 32420690 PMCID: PMC7339180 DOI: 10.1111/jcmm.15342] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 03/16/2020] [Accepted: 03/26/2020] [Indexed: 12/12/2022] Open
Abstract
Clinical and experimental studies show that angiotensin II (AngII) promotes vascular pathology via activation of AngII type 1 receptors (AT1Rs). We recently reported that NP-6A4, a selective peptide agonist for AngII type 2 receptor (AT2R), exerts protective effects on human vascular cells subjected to serum starvation or doxorubicin exposure. In this study, we investigated whether NP-6A4-induced AT2R activation could mitigate AngII-induced abdominal aortic aneurism (AAA) using AngII-treated Apoe-/- mice. Male Apoe-/- mice were infused with AngII (1 µg/kg/min) by implanting osmotic pumps subcutaneously for 28 days. A subset of mice was pre-treated subcutaneously with NP-6A4 (2.5 mg/kg/day) or vehicle for 14 days prior to AngII, and treatments were continued for 28 days. NP-6A4 significantly reduced aortic stiffness of the abdominal aorta induced by AngII as determined by ultrasound functional analyses and histochemical analyses. NP-6A4 also increased nitric oxide bioavailability in aortic tissues and suppressed AngII-induced increases in monocyte chemotactic protein-1, osteopontin and proteolytic activity of the aorta. However, NP-6A4 did not affect maximal intraluminal aortic diameter or AAA incidences significantly. These data suggest that the effects of AT2R agonist on vascular pathologies are selective, affecting the aortic stiffness and proteolytic activity without affecting the size of AAA.
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Affiliation(s)
- Neekun Sharma
- Department of Cardiovascular Medicine, University of Missouri, Columbia, MO, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Anthony M Belenchia
- Department of Cardiovascular Medicine, University of Missouri, Columbia, MO, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Ryan Toedebusch
- Department of Cardiovascular Medicine, University of Missouri, Columbia, MO, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Lakshmi Pulakat
- Department of Cardiovascular Medicine, University of Missouri, Columbia, MO, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA.,Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA.,Molecular Cardiology Research Institute, Department of Medicine, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Chetan P Hans
- Department of Cardiovascular Medicine, University of Missouri, Columbia, MO, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA.,Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA
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Zhuo JL, Li XC. Angiotensin III/AT 2 Receptor/NHE3 Signaling Pathway in the Proximal Tubules of the Kidney: A Novel Natriuretic and Antihypertensive Mechanism in Hypertension. J Am Heart Assoc 2020; 8:e012644. [PMID: 31039655 PMCID: PMC6512110 DOI: 10.1161/jaha.119.012644] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
See Article Kemp et al
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Affiliation(s)
- Jia L Zhuo
- 1 Laboratory of Receptor and Signal Transduction Department of Pharmacology and Toxicology University of Mississippi Medical Center Jackson MS.,2 Division of Nephrology Department of Medicine University of Mississippi Medical Center Jackson MS
| | - Xiao C Li
- 1 Laboratory of Receptor and Signal Transduction Department of Pharmacology and Toxicology University of Mississippi Medical Center Jackson MS.,2 Division of Nephrology Department of Medicine University of Mississippi Medical Center Jackson MS
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38
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Assersen KB, Sumners C, Steckelings UM. The Renin-Angiotensin System in Hypertension, a Constantly Renewing Classic: Focus on the Angiotensin AT 2-Receptor. Can J Cardiol 2020; 36:683-693. [PMID: 32389341 DOI: 10.1016/j.cjca.2020.02.095] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/28/2020] [Accepted: 02/29/2020] [Indexed: 02/07/2023] Open
Abstract
It is common knowledge that the renin-angiotensin system (RAS), in particular angiotensin II acting through the angiotensin AT1-receptor (AT1R), is pivotal for the regulation of blood pressure (BP) and extracellular volume. More recent findings have revealed that the RAS is far more complex than initially thought and that it harbours additional mediators and receptors, which are able to counteract and thereby fine-tune AT1R-mediated actions. This review will focus on the angiotensin AT2-receptor (AT2R), which is one of the "counter-regulatory" receptors within the RAS. It will review and discuss data related to the role of the AT2R in regulation of BP and focus on the following 3 questions: Do peripheral AT2R have an impact on BP regulation, and, if so, does this effect become apparent only under certain conditions? Are central nervous system AT2R involved in regulation of BP, and, if so, which brain areas are involved and what are the mechanisms? Does dysfunction of AT2R contribute to the pathogenesis of hypertension in preeclampsia?
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Affiliation(s)
- Kasper B Assersen
- Institute for Molecular Medicine, Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark
| | - Colin Sumners
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida, USA
| | - U Muscha Steckelings
- Institute for Molecular Medicine, Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark.
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Abstract
The active hormone of the renin-angiotensin system (RAS), angiotensin II (Ang II), is involved in several human diseases, driving the development and clinical use of several therapeutic drugs, mostly angiotensin I converting enzyme (ACE) inhibitors and angiotensin receptor type I (AT1R) antagonists. However, angiotensin peptides can also bind to receptors different from AT1R, in particular, angiotensin receptor type II (AT2R), resulting in biological and physiological effects different, and sometimes antagonistic, of their binding to AT1R. In the present Perspective, the components of the RAS and the therapeutic tools developed to control it will be reviewed. In particular, the characteristics of AT2R and tools to modulate its functions will be discussed. Agonists or antagonists to AT2R are potential therapeutics in cardiovascular diseases, for agonists, and in the control of pain, for antagonists, respectively. However, controlling their binding properties and their targeting to the target tissues must be optimized.
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Affiliation(s)
- Lucienne Juillerat-Jeanneret
- Transplantation Center, Department of Medicine, Centre Hospitalier Universitaire Vaudois (CHUV) and University of Lausanne (UNIL), Chemin des Boveresses 155, CH1011 Lausanne, Switzerland
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40
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Kemp BA, Howell NL, Gildea JJ, Keller SR, Carey RM. Identification of a Primary Renal AT 2 Receptor Defect in Spontaneously Hypertensive Rats. Circ Res 2020; 126:644-659. [PMID: 31997705 DOI: 10.1161/circresaha.119.316193] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
RATIONALE Previous studies identified a defect in Ang III (angiotensin III [des-aspartyl1-angiotensin II])-elicited AT2R (Ang type-2 receptor)-mediated natriuresis in renal proximal tubule cells of spontaneously hypertensive rats (SHR). OBJECTIVE This study aimed to delineate in prehypertensive SHR kidneys the receptor or postreceptor defect causing impaired AT2R signaling and renal sodium (Na+) retention by utilizing the selective AT2R agonist compound-21 (C-21). METHODS AND RESULTS Female 4-week-old Wistar Kyoto and SHR rats were studied after 24-hour systemic AT1R (Ang II type-1 receptor) blockade. Left kidneys received 30-minute renal interstitial infusions of vehicle followed by C-21 (20, 40, and 60 ng/[kg·min], each dose 30 minutes). Right kidneys received vehicle infusions. In Wistar Kyoto, C-21 dose-dependently increased urine Na+ excretion from 0.023±0.01 to 0.064±0.02, 0.087±0.01, and 0.089±0.01 µmol/min (P=0.008, P<0.0001, and P<0.0001, respectively) and renal interstitial fluid levels of AT2R downstream signaling molecule cGMP (cyclic guanosine 3',5' monophosphate) from 0.91±0.3 to 3.1±1.0, 5.9±1.2 and 5.3±0.5 fmol/mL (P=nonsignificant, P<0.0001, and P<0.0001, respectively). In contrast, C-21 did not increase urine Na+ excretion or renal interstitial cGMP in SHR. Mean arterial pressure was slightly higher in SHR but within the normotensive range and unaffected by C-21. In Wistar Kyoto, but not SHR, C-21 induced AT2R translocation to apical plasma membranes of renal proximal tubule cells, internalization/inactivation of NHE-3 (sodium-hydrogen exchanger-3) and Na+/K+ATPase (sodium-potassium-atpase) and phosphorylation of AT2R-cGMP downstream signaling molecules Src (Src family kinase), ERK (extracellular signal-related kinase), and VASP (vasodilator-stimulated phosphoprotein). To test whether cGMP could bypass the natriuretic defect in SHR, we infused 8-bromo-cGMP. This restored natriuresis, Na+ transporter internalization/inactivation, and Src and VASP phosphorylation, but not apical plasma membrane AT2R recruitment. In contrast, 8-bromo-cAMP administration had no effect on natriuresis or AT2R recruitment in SHR. CONCLUSIONS The results demonstrate a primary renal proximal tubule cell AT2R natriuretic defect in SHR that may contribute to the development of hypertension. Since the defect is abrogated by exogenous intrarenal cGMP, the renal cGMP pathway may represent a viable target for the treatment of hypertension. Visual Overview: An online visual overview is available for this article.
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Affiliation(s)
- Brandon A Kemp
- From the Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville (B.A.K., N.L.H., S.R.K., R.M.C.)
| | - Nancy L Howell
- From the Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville (B.A.K., N.L.H., S.R.K., R.M.C.)
| | - John J Gildea
- Department of Pathology, University of Virginia Health System, Charlottesville (J.J.G.)
| | - Susanna R Keller
- From the Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville (B.A.K., N.L.H., S.R.K., R.M.C.)
| | - Robert M Carey
- From the Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville (B.A.K., N.L.H., S.R.K., R.M.C.)
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Gu L, Wang J, Zhang DD, Meng X, Zhang Y, Zhang J, Zhang H, Guo X, Lin DH, Wang WH, Gu RM. Inhibition of AT2R and Bradykinin Type II Receptor (BK2R) Compromises High K + Intake-Induced Renal K + Excretion. Hypertension 2019; 75:439-448. [PMID: 31865783 DOI: 10.1161/hypertensionaha.119.13852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The inhibition of Type II angiotensin II receptor (AT2R) or BK2R (bradykinin type II receptor) stimulates basolateral Kir4.1/Kir5.1 in the distal convoluted tubule (DCT) and activates thiazide-sensitive NCC (Na-Cl cotransporter). The aim of the present study is to examine the role of AT2R and BK2R in mediating the effect of HK (high dietary K+) intake on the basolateral K+ channels, NCC, and renal K+ excretion. Feeding mice (male and female) with HK diet for overnight significantly decreased the basolateral K+ conductance, depolarized the DCT membrane, diminished the expression of pNCC (phosphorylated NCC) and tNCC (total NCC), and decreased thiazide-sensitive natriuresis. Overnight HK intake also increased the expression of cleaved ENaC-α and -γ subunits but had no effect on NKCC2 expression. Pretreatment of the mice (male and female) with PD123319 and HOE140 stimulated the expression of tNCC and pNCC, augmented hydrochlorothiazide-induced natriuresis, and increased the negativity of the DCT membrane. The deletion of Kir4.1 not only decreased the NCC activity but also abolished the stimulatory effect of PD123319 and HOE140 perfusion on NCC activity. Moreover, the effect of overnight HK loading on Kir4.1/Kir5.1 in the DCT and NCC expression/activity was compromised in the mice treated with AT2R/BK2R antagonists. Renal clearance study showed that inhibition of AT2R and BK2R impairs renal K+ excretion in response to overnight HK loading, and the mice pretreated with PD123319 and HOE140 were hyperkalemic during HK intake. We conclude that synergistic activation of AT2R and BK2R is required for the effect of overnight HK diet on Kir4.1/Kir5.1 in the DCT and NCC activity.
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Affiliation(s)
- Li Gu
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
| | - JunLin Wang
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
| | - Dan-Dan Zhang
- Department of Pharmacology, New York Medical College, Valhalla (D.-D. Z., D.-H.L, W.-H.W.)
| | - XinXin Meng
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
| | - YunHong Zhang
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
| | - JiaWen Zhang
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
| | - Hao Zhang
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
| | - XiWen Guo
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
| | - Dao-Hong Lin
- Department of Pharmacology, New York Medical College, Valhalla (D.-D. Z., D.-H.L, W.-H.W.)
| | - Wen-Hui Wang
- Department of Pharmacology, New York Medical College, Valhalla (D.-D. Z., D.-H.L, W.-H.W.)
| | - Rui-Min Gu
- From the Department of Physiology, Harbin Medical University, China (L.G., J.W., X.M., Y.Z, J.Z., H.Z., X.G., R.-M.G.)
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Lima VM, Lino CA, Senger N, de Oliveira Silva T, Fonseca RIB, Bader M, Santos RAS, Júnior JD, Barreto-Chaves MLM, Diniz GP. Angiotensin II type 2 receptor mediates high fat diet-induced cardiomyocyte hypertrophy and hypercholesterolemia. Mol Cell Endocrinol 2019; 498:110576. [PMID: 31520674 DOI: 10.1016/j.mce.2019.110576] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 09/05/2019] [Accepted: 09/09/2019] [Indexed: 12/30/2022]
Abstract
Obesity is the major risk factor for several cardiovascular and metabolic disorders. Previous studies reported that deletion of Angiotensin II type 2 receptor (AT2R) protects against metabolic dysfunctions induced by high fat (HF) diet. However, the role of AT2R in obesity-induced cardiac hypertrophy remains unclear. Male AT2R knockout (AT2RKO) and wild type (AT2RWT) mice were fed with control or HF diet for 10 weeks. HF diet increased cardiac expression of AT2R in obese mice. Deletion of AT2R did not affect body weight gain, glucose intolerance and fat mass gain induced by HF feeding. However, loss of AT2R prevented HF diet-induced hypercholesterolemia and cardiac remodeling. Mechanistically, we found that pharmacological inhibition or knockdown of AT2R prevented leptin-induced cardiomyocyte hypertrophy in vitro. Collectively, our results suggest that AT2R is involved in obesity-induced cardiac hypertrophy.
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Affiliation(s)
- Vanessa M Lima
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Caroline A Lino
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Nathalia Senger
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | | | - Renata I B Fonseca
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Michael Bader
- Max-Delbruck-Center for Molecular Medicine, Berlin, Germany
| | - Robson A S Santos
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Jose Donato Júnior
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | | | - Gabriela P Diniz
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
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Abstract
PURPOSE OF REVIEW Hypertension (HTN) is a widespread and growing disease, with medication intolerance and side-effect present among many. To address these obstacles novel pharmacotherapy is an active area of drug development. This review seeks to explore future drug therapy for HTN in the preclinical and clinical arenas. RECENT FINDINGS The future of pharmacological therapy in HTN consists of revisiting old pathways to find new targets and exploring wholly new approaches to provide additional avenues of treatment. In this review, we discuss the current status of the most recent drug therapy in HTN. New developments in well trod areas include novel mineralocorticoid antagonists, aldosterone synthase inhibitors, aminopeptidase-A inhibitors, natriuretic peptide receptor agonists, or the counter-regulatory angiotensin converting enzyme 2/angiotensin (Ang) (1-7)/Mas receptor axis. Neprilysin inhibitors popularized for heart failure may also still hold HTN potential. Finally, we examine unique systems in development never before used in HTN such as Na/H exchange inhibitors, vasoactive intestinal peptide agonists, and dopamine beta hydroxylase inhibitors. SUMMARY A concise review of future directions of HTN pharmacotherapy.
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Prevention of lipopolysaccharide-induced CD11b + immune cell infiltration in the kidney: role of AT 2 receptors. Biosci Rep 2019; 39:BSR20190429. [PMID: 31072913 PMCID: PMC6533357 DOI: 10.1042/bsr20190429] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/17/2019] [Accepted: 05/02/2019] [Indexed: 12/25/2022] Open
Abstract
Immune cell infiltration plays a central role in mediating endotoxemic acute kidney injury (AKI). Recently, we have reported the anti-inflammatory and reno-protective role of angiotensin-II type-2 receptor (AT2R) activation under chronic low-grade inflammatory condition in the obese Zucker rat model. However, the role of AT2R activation in preventing lipopolysaccharide (LPS)-induced early infiltration of immune cells, inflammation and AKI is not known. Mice were treated with AT2R agonist C21 (0.3 mg/kg), with and without AT2R antagonist PD123319 (5 mg/kg) prior to or concurrently with LPS (5 mg/kg) challenge. Prior-treatment with C21, but not concurrent treatment, significantly prevented the LPS-induced renal infiltration of CD11b+ immune cells, increase in the levels of circulating and/or renal chemotactic cytokines, particularly interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) and markers of renal dysfunction (blood urea nitrogen and albuminuria), while preserving anti-inflammatory interleukin-10 (IL-10) production. Moreover, C21 treatment in the absence of LPS increased renal and circulating IL-10 levels. To investigate the role of IL-10 in a cross-talk between epithelial cells and monocytes, we performed in vitro conditioned media (CM) studies in human kidney proximal tubular epithelial (HK-2) cells and macrophages (differentiated human monocytes, THP-1 cells). These studies revealed that the conditioned-media derived from the C21-treated HK-2 cells reduced LPS-induced THP-1 tumor necrosis factor-α (TNF-α) production via IL-10 originating from HK-2 cells. Our findings suggest that prior activation of AT2R is prophylactic in preventing LPS-induced renal immune cell infiltration and dysfunction, possibly via IL-10 pathway.
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Li XC, Soleimani M, Zhu D, Rubera I, Tauc M, Zheng X, Zhang J, Chen X, Zhuo JL. Proximal Tubule-Specific Deletion of the NHE3 (Na +/H + Exchanger 3) Promotes the Pressure-Natriuresis Response and Lowers Blood Pressure in Mice. Hypertension 2019; 72:1328-1336. [PMID: 30571224 DOI: 10.1161/hypertensionaha.118.10884] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The present study directly tested the hypothesis that deletion of the NHE3 (Na+/H+ exchanger 3) selectively in the proximal tubules of the kidney lowers basal blood pressure by increasing the pressure-natriuresis response in mice. Adult male and female, age-matched wild-type (WT) littermates and proximal tubule-specific NHE3 knockout mice (PT- Nhe3-/-; n=6-16 per group) were studied for (1) basal phenotypes of electrolytes and pH, blood pressure, and kidney function; (2) the pressure-natriuresis response using the mesenteric, celiac, and abdominal arterial occlusion technique; and (3) the natriuretic responses to acute saline expansion (0.9% NaCl, 10% body weight, intraperitoneal) or 2-week of 2% NaCl diet. Under basal conditions, PT- Nhe3-/- mice showed significantly lower systolic, diastolic, and mean arterial blood pressure ( P<0.01) than WT mice ( P<0.01). PT- Nhe3-/- mice also exhibited significantly greater diuretic ( P<0.01) and natriuretic responses than WT mice ( P<0.01), without altering 24-hour fecal Na+ excretion, plasma pH, Na+, and bicarbonate levels. In response to increased renal perfusion pressure by 30 mm Hg, the pressure-natriuresis response increased 5-fold in WT mice ( P<0.01), but it increased 8-fold in PT- Nhe3-/- mice ( P<0.01). In response to 10% acute saline expansion or 2-week 2% NaCl diet, more pronounced natriuretic responses were demonstrated in PT- Nhe3-/- than WT mice ( P<0.01). Our results support the scientific premise and physiological relevance that NHE3 in the proximal tubules plays an essential role in maintaining basal blood pressure homeostasis, and genetic deletion of NHE3 selectively in the proximal tubules of the kidney lowers blood pressure by increasing the pressure natriuretic response.
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Affiliation(s)
- Xiao C Li
- From the Division of Nephrology, Department of Pharmacology and Toxicology and Department of Medicine, University of Mississippi Medical Center, Jackson (X.C.L., X.Z., J.Z., X.C., J.L.Z.)
| | - Manoocher Soleimani
- Division of Nephrology and Hypertension, Department of Internal Medicine, The University of Cincinnati College of Medicine, OH (M.S.)
| | - Dongmin Zhu
- Department of Outpatients, Guangxi Science and Technology University No. 1 Affiliated Hospital, Liuzhou, China (D.Z.)
| | - Isabelle Rubera
- Laboratoire Centre National de la Recherche Scientifique (CNRS) 3472 LP2M, Université de Nice Sophia Antipolis, Nice Cedex 2, France (I.R., M.T.)
| | - Michel Tauc
- Laboratoire Centre National de la Recherche Scientifique (CNRS) 3472 LP2M, Université de Nice Sophia Antipolis, Nice Cedex 2, France (I.R., M.T.)
| | - Xiaowen Zheng
- From the Division of Nephrology, Department of Pharmacology and Toxicology and Department of Medicine, University of Mississippi Medical Center, Jackson (X.C.L., X.Z., J.Z., X.C., J.L.Z.).,Department of Emergency Medicine, Second Affiliated Hospital, Guangxi Medical University, Nanning, China (X.Z., J.Z.)
| | - Jianfeng Zhang
- From the Division of Nephrology, Department of Pharmacology and Toxicology and Department of Medicine, University of Mississippi Medical Center, Jackson (X.C.L., X.Z., J.Z., X.C., J.L.Z.)
| | - Xu Chen
- From the Division of Nephrology, Department of Pharmacology and Toxicology and Department of Medicine, University of Mississippi Medical Center, Jackson (X.C.L., X.Z., J.Z., X.C., J.L.Z.)
| | - Jia L Zhuo
- From the Division of Nephrology, Department of Pharmacology and Toxicology and Department of Medicine, University of Mississippi Medical Center, Jackson (X.C.L., X.Z., J.Z., X.C., J.L.Z.).,Department of Emergency Medicine, Second Affiliated Hospital, Guangxi Medical University, Nanning, China (X.Z., J.Z.)
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Xiao L, Xu B, Zhou L, Tan RJ, Zhou D, Fu H, Li A, Hou FF, Liu Y. Wnt/β-catenin regulates blood pressure and kidney injury in rats. Biochim Biophys Acta Mol Basis Dis 2019; 1865:1313-1322. [PMID: 30710617 DOI: 10.1016/j.bbadis.2019.01.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/14/2019] [Accepted: 01/28/2019] [Indexed: 02/06/2023]
Abstract
Activation of the renin-angiotensin system (RAS) plays a pivotal role in mediating hypertension, chronic kidney and cardiovascular diseases. As Wnt/β-catenin regulates multiple RAS genes, we speculated that this developmental signaling pathway might also participate in blood pressure (BP) regulation. To test this, we utilized two rat models of experimental hypertension: chronic angiotensin II infusion and remnant kidney after 5/6 nephrectomy. Inhibition of Wnt/β-catenin by ICG-001 blunted angiotensin II-induced hypertension. Interestingly, angiotensin II was able to induce the expression of multiple Wnt genes in vivo and in vitro, thereby creating a vicious cycle between Wnt/β-catenin and RAS activation. In the remnant kidney model, renal β-catenin was upregulated, and delayed administration of ICG-001 also blunted BP elevation and abolished the induction of angiotensinogen, renin, angiotensin-converting enzyme and angiotensin II type 1 receptor. ICG-001 also reduced albuminuria, serum creatinine and blood urea nitrogen, and inhibited renal expression of fibronectin, collagen I and plasminogen activator inhibitor-1, and suppressed the infiltration of CD3+ T cells and CD68+ monocytes/macrophages. In vitro, incubation with losartan prevented Wnt/β-catenin-mediated fibronectin, α-smooth muscle actin and Snail1 expression, suggesting that the fibrogenic action of Wnt/β-catenin is dependent on RAS activation. Taken together, these results suggest an intrinsic linkage of Wnt/β-catenin signaling with BP regulation. Our studies also demonstrate that hyperactive Wnt/β-catenin can drive hypertension and kidney damage via RAS activation.
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Affiliation(s)
- Liangxiang Xiao
- State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Nephrology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Bo Xu
- State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Nephrology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Lili Zhou
- State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Roderick J Tan
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Dong Zhou
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Haiyan Fu
- State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Aiqing Li
- State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Fan Fan Hou
- State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Youhua Liu
- State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America.
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Forrester SJ, Booz GW, Sigmund CD, Coffman TM, Kawai T, Rizzo V, Scalia R, Eguchi S. Angiotensin II Signal Transduction: An Update on Mechanisms of Physiology and Pathophysiology. Physiol Rev 2018; 98:1627-1738. [PMID: 29873596 DOI: 10.1152/physrev.00038.2017] [Citation(s) in RCA: 643] [Impact Index Per Article: 107.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The renin-angiotensin-aldosterone system plays crucial roles in cardiovascular physiology and pathophysiology. However, many of the signaling mechanisms have been unclear. The angiotensin II (ANG II) type 1 receptor (AT1R) is believed to mediate most functions of ANG II in the system. AT1R utilizes various signal transduction cascades causing hypertension, cardiovascular remodeling, and end organ damage. Moreover, functional cross-talk between AT1R signaling pathways and other signaling pathways have been recognized. Accumulating evidence reveals the complexity of ANG II signal transduction in pathophysiology of the vasculature, heart, kidney, and brain, as well as several pathophysiological features, including inflammation, metabolic dysfunction, and aging. In this review, we provide a comprehensive update of the ANG II receptor signaling events and their functional significances for potential translation into therapeutic strategies. AT1R remains central to the system in mediating physiological and pathophysiological functions of ANG II, and participation of specific signaling pathways becomes much clearer. There are still certain limitations and many controversies, and several noteworthy new concepts require further support. However, it is expected that rigorous translational research of the ANG II signaling pathways including those in large animals and humans will contribute to establishing effective new therapies against various diseases.
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Affiliation(s)
- Steven J Forrester
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - George W Booz
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Curt D Sigmund
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Thomas M Coffman
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Tatsuo Kawai
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Victor Rizzo
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Rosario Scalia
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Satoru Eguchi
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
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Abstract
PURPOSE OF REVIEW Angiotensin type 2 receptor (AT2R) and receptor Mas (MasR) are part of the "protective arm" of the renin angiotensin system. Gene and pharmacological manipulation studies reveal that AT2R and MasR are involved in natriuretic, vasodilatory, and anti-inflammatory responses and in lowering blood pressure in various animal models under normal and pathological conditions such as salt-sensitive hypertension, obesity, and diabetes. The scope of this review is to discuss co-localization and heterodimerization as potential molecular mechanisms of AT2R- and MasR-mediated functions including antihypertensive activities. RECENT FINDINGS Accumulating evidences show that AT2R and MasR are co-localized, make a heterodimer, and are functionally interdependent in producing their physiological responses. Moreover, ang-(1-7) preferably may be an AT1R-biased agonist while acting as a MasR agonist. The physical interactions of AT2R and MasR appear to be an important mechanism by which these receptors are involved in blood pressure regulation and antihypertensive activity. Whether heteromers of these receptors influence affinity or efficacy of endogenous or synthetic agonists remains a question to be considered.
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MESH Headings
- Animals
- Blood Pressure/physiology
- Dimerization
- Humans
- Hypertension/metabolism
- Hypertension/physiopathology
- Proto-Oncogene Mas
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins/physiology
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, Angiotensin, Type 1/physiology
- Receptor, Angiotensin, Type 2/metabolism
- Receptor, Angiotensin, Type 2/physiology
- Receptors, G-Protein-Coupled/metabolism
- Receptors, G-Protein-Coupled/physiology
- Renin-Angiotensin System/physiology
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Affiliation(s)
- Sanket Patel
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health 2, Room 3046, 4849 Calhoun Street, Houston, TX, 77204-5000, USA
| | - Tahir Hussain
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health 2, Room 3046, 4849 Calhoun Street, Houston, TX, 77204-5000, USA.
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Abstract
PURPOSE OF REVIEW This review updates major new findings and concepts introduced during the past year on the role of angiotensin II (Ang II) subtype 2 receptors (AT2Rs) in the control of blood pressure and renal function. RECENT FINDINGS AT2R activation prevents sodium (Na) retention and lowers blood pressure in the Ang II infusion model of experimental hypertension and prevents salt-sensitive hypertension in the obese Zucker rat model of obesity and the metabolic syndrome. Ang II metabolite, des-aspartyl-Ang II (Ang III) is the predominant AT2R agonist in the kidney and possibly also in the vasculature; a novel synthetic Ang III peptide, β-Pro-Ang III, is vasodepressor and lowers blood pressure in conscious spontaneously hypertensive rats in the presence of low-level Ang II type 1 receptor (AT1R) blockade. Because nitric oxide is a product of AT2R activation, a potential feed-forward loop, wherein nitric oxide increases AT2R transcription, may reinforce the beneficial actions of AT2R in the long term. AT2R activation also reduces proteinuria and oxidative stress in glomerulosclerotic kidneys of high-salt obese Zucker rats. SUMMARY Studies during the past year have helped to clarify the physiological and pathophysiological roles of AT2Rs and have enhanced the promise of AT2R agonists in cardiovascular and renal disease.
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50
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Abstract
PURPOSE OF REVIEW Angiotensin II is a main regulator of kidney function. Renal actions mediated by the angiotensin AT1 receptor have been well known for many years. In contrast, several details of angiotensin AT2 receptor actions in kidney physiology and pathophysiology were only described very recently. These findings are reviewed in this article. RECENT FINDINGS Regarding the role of the angiotensin AT2 receptor in kidney physiology, a major recent finding was that the AT2 receptor-mediated inhibition of Na-H exchanger-3 and Na/K-ATPase in the renal proximal tubules is caused by internalisation of these transporters, thus reducing reabsorption and increasing natriuresis/diuresis. Regarding renal pathology, several studies demonstrated an attenuation of renal injury caused by diabetes or by obesity with or without high-salt diet through anti-inflammatory, antifibrotic, and antioxidative mechanisms. Generally, AT2 receptor expression seems increased and AT2 receptor-mediated effects stronger in female and obese animals. SUMMARY The recent findings about the role of the angiotensin AT2 receptor in renal health and disease strongly suggest that pharmacological targeting of this receptor with selective agonists is a promising therapeutic strategy for inducing diuresis/natriuresis (also additive to established diuretics) and for the treatment of diabetic nephropathy or kidney disease of other pathogenesis.
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