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Haas AV, En Yee L, Yuan YE, Wong YH, Hopkins PN, Jeunemaitre X, Lasky-Su J, Williams JS, Adler GK, Williams GH. Genetic Predictors of Salt Sensitivity of Blood Pressure: The Additive Impact of 2 Hits in the Same Biological Pathway. Hypertension 2021; 78:1809-1817. [PMID: 34757767 DOI: 10.1161/hypertensionaha.121.18033] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Andrea V Haas
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (A.V.H., Y.E.Y., J.S.W., G.K.A., G.H.W.)
| | - Li En Yee
- Cell and Molecular Biology Laboratory, Department of Cellular Biology and Pharmacology, Faculty of Medicine and Health Sciences, UCSI University, Cheras, Kuala Lumpur, Malaysia (L.E.Y., Y.H.W.)
| | - Yan E Yuan
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (A.V.H., Y.E.Y., J.S.W., G.K.A., G.H.W.)
| | - Yin H Wong
- Cell and Molecular Biology Laboratory, Department of Cellular Biology and Pharmacology, Faculty of Medicine and Health Sciences, UCSI University, Cheras, Kuala Lumpur, Malaysia (L.E.Y., Y.H.W.)
| | - Paul N Hopkins
- Professor Emeritus, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City (P.N.H.)
| | - Xavier Jeunemaitre
- Université de Paris, Inserm U970, Paris Centre de Recherche Cardiovasculaire (X.J.).,AP-HP, Hôpital Européen Georges Pompidou, Paris (X.J.)
| | - Jessica Lasky-Su
- Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (J.L.-S.)
| | - Jonathan S Williams
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (A.V.H., Y.E.Y., J.S.W., G.K.A., G.H.W.)
| | - Gail K Adler
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (A.V.H., Y.E.Y., J.S.W., G.K.A., G.H.W.)
| | - Gordon H Williams
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (A.V.H., Y.E.Y., J.S.W., G.K.A., G.H.W.)
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Ranjit S, Wong JY, Tan JW, Sin Tay C, Lee JM, Yin Han Wong K, Pojoga LH, Brooks DL, Garza AE, Maris SA, Katayama IA, Williams JS, Rivera A, Adler GK, Williams GH, Romero JR. Sex-specific differences in endoplasmic reticulum aminopeptidase 1 modulation influence blood pressure and renin-angiotensin system responses. JCI Insight 2019; 4:129615. [PMID: 31672933 DOI: 10.1172/jci.insight.129615] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 09/19/2019] [Indexed: 12/24/2022] Open
Abstract
Salt sensitivity of blood pressure (SSBP) and hypertension are common, but the underlying mechanisms remain unclear. Endoplasmic reticulum aminopeptidase 1 (ERAP1) degrades angiotensin II (ANGII). We hypothesized that decreasing ERAP1 increases BP via ANGII-mediated effects on aldosterone (ALDO) production and/or renovascular function. Compared with WT littermate mice, ERAP1-deficient (ERAP1+/-) mice had increased tissue ANGII, systolic and diastolic BP, and SSBP, indicating that ERAP1 deficiency leads to volume expansion. However, the mechanisms underlying the volume expansion differed according to sex. Male ERAP1+/- mice had increased ALDO levels and normal renovascular responses to volume expansion (decreased resistive and pulsatility indices and increased glomerular volume). In contrast, female ERAP1+/- mice had normal ALDO levels but lacked normal renovascular responses. In humans, ERAP1 rs30187, a loss-of-function gene variant that reduces ANGII degradation in vitro, is associated with hypertension. In our cohort from the Hypertensive Pathotype (HyperPATH) Consortium, there was a significant dose-response association between rs30187 risk alleles and systolic and diastolic BP as well as renal plasma flow in men, but not in women. Thus, lowering ERAP1 led to volume expansion and increased BP. In males, the volume expansion was due to elevated ALDO with normal renovascular function, whereas in females the volume expansion was due to impaired renovascular function with normal ALDO levels.
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Manosroi W, Williams GH. Genetics of Human Primary Hypertension: Focus on Hormonal Mechanisms. Endocr Rev 2019; 40:825-856. [PMID: 30590482 PMCID: PMC6936319 DOI: 10.1210/er.2018-00071] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 09/07/2018] [Indexed: 02/06/2023]
Abstract
Increasingly, primary hypertension is being considered a syndrome and not a disease, with the individual causes (diseases) having a common sign-an elevated blood pressure. To determine these causes, genetic tools are increasingly employed. This review identified 62 proposed genes. However, only 21 of them met our inclusion criteria: (i) primary hypertension, (ii) two or more supporting cohorts from different publications or within a single publication or one supporting cohort with a confirmatory genetically modified animal study, and (iii) 600 or more subjects in the primary cohort; when including our exclusion criteria: (i) meta-analyses or reviews, (ii) secondary and monogenic hypertension, (iii) only hypertensive complications, (iv) genes related to blood pressure but not hypertension per se, (v) nonsupporting studies more common than supporting ones, and (vi) studies that did not perform a Bonferroni or similar multiassessment correction. These 21 genes were organized in a four-tiered structure: distant phenotype (hypertension); intermediate phenotype [salt-sensitive (18) or salt-resistant (0)]; subintermediate phenotypes under salt-sensitive hypertension [normal renin (4), low renin (8), and unclassified renin (6)]; and proximate phenotypes (specific genetically driven hypertensive subgroup). Many proximate hypertensive phenotypes had a substantial endocrine component. In conclusion, primary hypertension is a syndrome; many proposed genes are likely to be false positives; and deep phenotyping will be required to determine the utility of genetics in the treatment of hypertension. However, to date, the positive genes are associated with nearly 50% of primary hypertensives, suggesting that in the near term precise, mechanistically driven treatment and prevention strategies for the specific primary hypertension subgroups are feasible.
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Affiliation(s)
- Worapaka Manosroi
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.,Division of Endocrinology and Metabolism, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Gordon H Williams
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
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Gupta T, Connors M, Tan JW, Manosroi W, Ahmed N, Ting PY, Garza AE, Romero JR, Hopkins PN, Williams JS, Williams GH. Striatin Gene Polymorphic Variants Are Associated With Salt Sensitive Blood Pressure in Normotensives and Hypertensives. Am J Hypertens 2017; 31:124-131. [PMID: 28985281 DOI: 10.1093/ajh/hpx146] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 08/03/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Understanding the interactions between genetics, sodium (Na+) intake, and blood pressure (BP) will help overcome the lack of individual specificity in our current treatment of hypertension. This study had 3 goals: expand on the relationship between striatin gene (STRN) status and salt-sensitivity of BP (SSBP); evaluate the status of Na+ and volume regulating systems by striatin risk allele status; evaluate potential SSBP mechanisms. METHODS We assessed the relationship between STRN status in humans (HyperPATH cohort) and SSBP and on volume regulated systems in humans and a striatin knockout mouse (STRN+/-). RESULTS The previously identified association between a striatin risk allele and systolic SSBP was demonstrated in a new cohort (P = 0.01). The STRN-SSBP association was significant for the combined cohort (P = 0.003; β = +5.35 mm Hg systolic BP/risk allele) and in the following subgroups: normotensives, hypertensives, men, and older subjects. Additionally, we observed a lower epinephrine level in risk allele carriers (P = 0.014) and decreased adrenal medulla phenylethanolamine N-methyltransferase (PNMT) in STRN+/- mice. No significant associations were observed with other volume regulated systems. CONCLUSIONS These results support the association between a variant of striatin and SSBP and extend the findings to normotensive individuals and other subsets. In contrast to most salt-sensitive hypertensives, striatin-associated SSBP is associated with normal plasma renin activity and reduced epinephrine levels. These data provide clues to the underlying cause and a potential pathway to achieve, specific, personalized treatment, and prevention.
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Affiliation(s)
- Tina Gupta
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
| | - Molly Connors
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
| | - Jia Wei Tan
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
- Cell and Molecular Biology Laboratory, Department of Cellular Biology & Pharmacology, Faculty of Medicine & Health Sciences, UCSI University, Malaysia
| | - Worapaka Manosroi
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
- Division of Endocrinology and Metabolism, Bangkok Chiang Mai Hospital, Thailand
| | - Noha Ahmed
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
| | - Pei Yee Ting
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
- Division of Endocrinology and Metabolism, Bangkok Chiang Mai Hospital, Thailand
| | - Amanda E Garza
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
| | - Jose R Romero
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
| | - Paul N Hopkins
- Cardiovascular Genetics Unit, Cardiology Division, Department of Medicine, University of Utah School of Medicine, USA
| | - Jonathan S Williams
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
| | - Gordon H Williams
- Division of Endocrinology, Diabetes, Hypertension, Brigham and Women’s, Harvard Medical School, USA
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5
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Toering TJ, Gant CM, Visser FW, van der Graaf AM, Laverman GD, Danser AHJ, Faas MM, Navis G, Lely AT. Sex differences in renin-angiotensin-aldosterone system affect extracellular volume in healthy subjects. Am J Physiol Renal Physiol 2017; 314:F873-F878. [PMID: 28592435 DOI: 10.1152/ajprenal.00109.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Several studies reported sex differences in aldosterone. It is unknown whether these differences are associated with differences in volume regulation. Therefore we studied both aldosterone and extracellular volume in men and women on different sodium intakes. In healthy normotensive men ( n = 18) and premenopausal women ( n = 18) we investigated plasma aldosterone, blood pressure, and extracellular volume (125I-iothalamate), during both low (target intake 50 mmol Na+/day) and high sodium intake (target intake 200 mmol Na+/day) in a crossover setup. Furthermore, we studied the adrenal response to angiotensin II infusion (0.3, 1.0, and 3.0 ng·kg-1·min-1 for 1 h) on both sodium intakes. Men had a significantly higher plasma aldosterone, extracellular volume, and systolic blood pressure than women during high sodium intake ( P < 0.05). During low sodium intake, extracellular volume and blood pressure were higher in men as well ( P < 0.05), whereas the difference in plasma aldosterone was no longer significant ( P = 0.252). The adrenal response to exogenous angiotensin II was significantly lower in men than in women on both sodium intakes. Constitutive sex differences in the regulation of aldosterone, characterized by a higher aldosterone and a lower adrenal response to exogenous angiotensin II infusion in men, are associated with a higher extracellular volume and blood pressure in men. These findings suggest that sex differences in the regulation of aldosterone contribute to differences in volume regulation between men and women.
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Affiliation(s)
- Tsjitske J Toering
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
| | - Christina M Gant
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands.,Department of Internal Medicine-Nephrology, Ziekenhuisgroep Twente Almelo, Almelo, The Netherlands
| | - Folkert W Visser
- Department of Internal Medicine-Nephrology, Ziekenhuisgroep Twente Almelo, Almelo, The Netherlands
| | - Anne Marijn van der Graaf
- Division of Medical Biology, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
| | - Gozewijn D Laverman
- Department of Internal Medicine-Nephrology, Ziekenhuisgroep Twente Almelo, Almelo, The Netherlands
| | - A H Jan Danser
- Division of Pharmacology and Vascular Medicine, Department of Internal Medicine, Erasmus University Medical Center , Rotterdam , The Netherlands
| | - Marijke M Faas
- Division of Medical Biology, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands.,Department of Obstetrics and Gynecology, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
| | - Gerjan Navis
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
| | - A Titia Lely
- Department of Obstetrics and Gynecology, University of Utrecht, University Medical Center Utrecht , Utrecht , The Netherlands
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Garza AE, Rariy CM, Sun B, Williams J, Lasky-Su J, Baudrand R, Yao T, Moize B, Hafiz WM, Romero JR, Adler GK, Ferri C, Hopkins PN, Pojoga LH, Williams GH. Variants in striatin gene are associated with salt-sensitive blood pressure in mice and humans. Hypertension 2014; 65:211-217. [PMID: 25368024 DOI: 10.1161/hypertensionaha.114.04233] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Striatin is a novel protein that interacts with steroid receptors and modifies rapid, nongenomic activity in vitro. We tested the hypothesis that striatin would in turn affect mineralocorticoid receptor function and consequently sodium, water, and blood pressure homeostasis in an animal model. We evaluated salt sensitivity of blood pressure in novel striatin heterozygote knockout mice. Compared with wild type, striatin heterozygote exhibited a significant increase in blood pressure when sodium intake was increased from restricted (0.03%) to liberal (1.6%) sodium. Furthermore, renal expression of mineralocorticoid receptor and its genomic downstream targets serum/glucocorticoid-regulated kinase 1, and epithelial sodium channel was increased in striatin heterozygote versus wild-type mice on liberal sodium intake while the pAkt/Akt ratio, readout of mineralocorticoid receptor's rapid, nongenomic pathway, was reduced. To determine the potential clinical relevance of these findings, we tested the association between single nucleotide polymorphic variants of striatin gene and salt sensitivity of blood pressure in 366 white hypertensive subjects. HapMap-derived tagging single nucleotide polymorphisms identified an association of rs2540923 with salt sensitivity of blood pressure (odds ratio, 6.25; 95% confidence interval, 1.7-20; P=0.01). These data provide the first in vivo evidence in humans and rodents that associates striatin with markers of mineralocorticoid receptor activity. The data also support the hypothesis that the rapid, nongenomic mineralocorticoid receptor pathway (mediated via striatin) has a role in modulating the interaction between salt intake and blood pressure.
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Affiliation(s)
- Amanda E Garza
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Chevon M Rariy
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Bei Sun
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Jonathan Williams
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Jessica Lasky-Su
- Channing Department of Network Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Rene Baudrand
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA.,Department of Endocrinology, School Of Medicine, Pontificia Universidad Catolica De Chile, Santiago 8330074, Chile
| | - Tham Yao
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Burhanuddin Moize
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Wan M Hafiz
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Jose R Romero
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Gail K Adler
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Claudio Ferri
- Division of Internal Medicine & Nephrology and School of Internal Medicine, University of L'Aquila - San Salvatore Hospital, V.le San Salvatore - Delta 6 Building, Coppito 67100 AQ, Italy
| | - Paul N Hopkins
- Division of Cardiovascular Genetics, University of Utah School of Medicine, Salt Lake City, UT 84108
| | - Luminita H Pojoga
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
| | - Gordon H Williams
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School. Boston, MA 02115, USA
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McDaniel DO, Rigney D, Olivier J, McDaniel KY, Brock M, Redmond P, Porter J. Trauma Induced Inflammation, Sepsis and Ageing. AGEING INTERNATIONAL 2013. [DOI: 10.1007/s12126-013-9195-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Blood pressure and renin-angiotensin system resetting in transgenic rats with elevated plasma Val5-angiotensinogen. J Hypertens 2013; 30:1597-605. [PMID: 22728903 DOI: 10.1097/hjh.0b013e3283550f76] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Increases in plasma angiotensinogen (Ang-N) due to genetic polymorphisms or pharmacological stimuli like estrogen have been associated with a blood pressure (BP) rise, increased salt sensitivity and cardiovascular risk. The relationship between Ang-N, the resetting of the renin-angiotensin system, and BP still remains unclear. Angiotensin (Ang) II-induced genetic hypertension should respond to lisinopril treatment. METHODS A new transgenic rat line (TGR) with hepatic overexpression of native (rat) Ang-N was established to study high plasma Ang-N. The transgene contained a mutation producing Val(5)-Ang-II, which was measured separately from nontransgenic Ile-Ang-II in plasma and renal tissue. RESULTS Male homozygous TGR had increased plasma Ang-N (~20-fold), systolic BP (ΔBP+26 mmHg), renin activity (~2-fold), renin activity/concentration (5-fold), total Ang-II (~2-fold, kidney 1.7-fold) but decreased plasma renin concentrations (-46%, kidney -85%) and Ile(5)-Ang-I and II (-93%, -94%) vs. controls. Heterozygous TGR exhibited ~10-fold higher plasma Ang-N and 17 mmHg ΔBP. Lisinopril decreased their SBP (-23 vs. -13 mmHg in controls), kidney Ang-II/I (~3-fold vs. ~2-fold) and Ile(5)-Ang-II (-70 vs. -40%), and increased kidney renin and Ile(5)-Ang-I (>2.5-fold vs. <2.5-fold). Kidney Ang-II remained higher and renin lower in TGR compared with controls. CONCLUSION High plasma Ang-N increases plasma and kidney Ang-II levels, and amplifies the plasma and renal Ang-II response to a given change in renal renin secretion. This enzyme-kinetic amplification dominates over the Ang-II mediated feedback reduction of renin secretion. High Ang-N levels thus facilitate hypertension via small increases of Ang II and may influence the effectiveness of renin-angiotensin system inhibitors.
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Abstract
OBJECTIVE AND METHODS A loss-of-function cytosine (C) for thymidine (T) transition at nucleotide 8590 of CYP4A11 has been associated with increased blood pressure in humans. We tested the hypothesis that CYP4A11 T8590C genotype is associated with salt sensitivity in the International Hypertensive Pathotype cohort. RESULTS CYP4A11 T8590C genotype was associated with hypertension in whites. Among normotensive individuals, CYP4A11 T8590C genotype was associated with mean arterial pressure (MAP) during both high and low salt diets, such that there was no relationship between genotype and salt sensitivity of blood pressure. Among hypertensive individuals, CYP4A11 T8590C genotype did not associate with MAP during high salt intake, whereas MAP decreased with increasing number of C alleles during salt restriction. Consequently, among hypertensive individuals, change in MAP with salt restriction was greatest in individuals homozygous for the C allele (-10.9 ± 9.9, -11.1 ± 12.3, and -18.8 ± 12.0 mmHg in TT, CT, and CC groups, respectively, P = 0.02). In both normotensive and hypertensive individuals, individuals homozygous for the C allele exhibited an attenuated increase in renal blood flow during high salt. CYP4A11 genotype did not affect pressor responses to Angiotensin II in normotensive or hypertensive individuals. CONCLUSION The loss-of-function CYP4A11 8590C allele is associated with a diagnosis of hypertension and, in normotensive individuals, with higher blood pressure regardless of salt intake. Among hypertensive individuals, the C allele is associated with salt-sensitive blood pressure. Impaired renal vasodilation during high salt intake may contribute to salt sensitivity. Studies are needed to determine whether CYP4A11 T8590C genotype predicts responses to medications that affect sodium homeostasis in hypertensive individuals.
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Sun B, Williams JS, Pojoga L, Chamarthi B, Lasky-Su J, Raby BA, Hopkins PN, Jeunemaitre X, Brown NJ, Ferri C, Williams GH. Renin gene polymorphism: its relationship to hypertension, renin levels and vascular responses. J Renin Angiotensin Aldosterone Syst 2011; 12:564-71. [PMID: 21490026 PMCID: PMC3444254 DOI: 10.1177/1470320311405873] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The renin gene has been previously reported to be associated with essential hypertension in a variety of ethnic groups. However, no studies have systematically evaluated the relationship between single nucleotide polymorphisms (SNPs) representing coverage of the entire renin gene and hypertension risk. To evaluate the association between renin gene variation and hypertension we investigated data on HyperPATH cohort with 570 hypertensive and 222 normotensive Caucasian subjects. Six tagging SNPs and resultant haplotypes were tested for associations with hypertension risk, followed by mean arterial pressure (MAP), plasma renin activity (PRA) and the change in MAP in response to angiotensin II (AngII) infusion (AngII ΔMAP). The A allele of SNP rs6693954 and the haplotype containing rs6696954A were significantly associated with higher risk for hypertension (OR = 1.98, p = 0.0001; OR = 1.63 p = 0.0005, respectively). The same haplotype block was also associated with altered PRA levels and blunted AngII ΔMAP (global p-value = 0.02, 0.047, respectively). Our results confirm that polymorphisms in the renin gene are associated with increased risk for hypertension in an independent cohort, and that the underlying mechanism may reside in the interaction of renin activity and vascular responsiveness to angiotensin II.
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Affiliation(s)
- Bei Sun
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115 , USA
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11
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Underwood PC, Sun B, Williams JS, Pojoga LH, Raby B, Lasky-Su J, Hunt S, Hopkins PN, Jeunemaitre X, Adler GK, Williams GH. The association of the angiotensinogen gene with insulin sensitivity in humans: a tagging single nucleotide polymorphism and haplotype approach. Metabolism 2011; 60:1150-7. [PMID: 21306748 PMCID: PMC3115454 DOI: 10.1016/j.metabol.2010.12.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 12/14/2010] [Accepted: 12/15/2010] [Indexed: 01/01/2023]
Abstract
The purpose of this study was to clarify the association of the angiotensinogen gene (AGT) with insulin sensitivity using single nucleotide polymorphism (SNP) and haplotype analyses in a white cohort. A candidate gene association study was conducted in white persons with and without hypertension (N = 449). Seventeen SNPs of the AGT gene and their haplotypes were analyzed for an association with homeostasis model assessment of insulin resistance (HOMA-IR). Multivariate regression model accounting for age, sex, body mass index, hypertension status, study site, and sibling relatedness was used to test the hypothesis. Nine of the 17 SNPs were significantly associated with lower HOMA-IR levels. Homozygous minor allele carriers of the most significant SNP, rs2493134 (GG), a surrogate for the gain-of-function mutation rs699 (AGT p.M268T), had significantly lower HOMA-IR levels (P = .0001) than heterozygous or homozygous major allele carriers (AG, AA). Direct genotyping of rs699 in a subset of the population showed similar results, with minor allele carriers exhibiting significantly decreased HOMA-IR levels (P = .003). Haplotype analysis demonstrated that haplotypes rs2493137A|rs5050A|rs3789678G|rs2493134A and rs2004776G|rs11122576A|rs699T|rs6687360G were also significantly associated with HOMA-IR (P = .0009, P = .02), and these results were driven by rs2493134 and rs699. This study confirms an association between the AGT gene and insulin sensitivity in white humans. Haplotype analysis extends this finding and implicates SNPs rs2493134 and rs699 as the most influential. Thus, AGT gene variants, previously shown to be associated with AGT levels, are also associated with insulin sensitivity; suggesting a relationship between the AGT gene, AGT levels, and insulin sensitivity in humans.
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Affiliation(s)
- Patricia C Underwood
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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12
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Vaidya A, Sun B, Forman JP, Hopkins PN, Brown NJ, Kolatkar NS, Williams GH, Williams JS. The Fok1 vitamin D receptor gene polymorphism is associated with plasma renin activity in Caucasians. Clin Endocrinol (Oxf) 2011; 74:783-90. [PMID: 21521263 PMCID: PMC3089671 DOI: 10.1111/j.1365-2265.2011.03991.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVES 25-Hydroxyvitamin D (25(OH)D) deficiency and excess activity of the renin-angiotensin system (RAS) are both associated with cardiovascular disease. Vitamin D interacts with the vitamin D receptor (VDR) to negatively regulate renin expression in mice; however, human studies linking genetic variation in the VDR with renin are lacking. We evaluated (i) whether genetic variation in the VDR at the Fok1 polymorphism was associated with plasma renin activity (PRA) in a population of hypertensives and a separate population of normotensives and (ii) whether the association between Fok1 genotype and PRA was independent of 25(OH)D levels. DESIGN/PATIENTS/MEASUREMENTS Genetic association study, assuming an additive model of inheritance, of 375 hypertensive and 146 normotensive individuals from the HyperPATH cohort, who had PRA assessments after 1 week of high dietary sodium balance (HS) and l week of low dietary sodium balance (LS). RESULTS The minor allele (T) at the Fok1 polymorphism was significantly associated with lower PRA in hypertensives (LS: β = -0·22, P < 0·01; HS: β = -0·19, P < 0·01); when repeated in normotensives, a similar relationship was observed (LS: β = -0·17, P < 0·05; HS: β = -0·18, P = 0·14). In multivariable analyses, both higher 25(OH)D levels and the T allele at Fok1 were independently associated with lower PRA in hypertensives; however, 25(OH)D was not associated with PRA in normotensives. CONCLUSIONS Genetic variation at the Fok1 polymorphism of the VDR gene, in combination with 25(OH)D levels, was associated with PRA in hypertension. These findings support the vitamin D-VDR complex as a potential regulator of renin activity in humans.
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Affiliation(s)
- Anand Vaidya
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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Abstract
Blood pressure and hypertension have significant genetic underpinnings that may be age-dependent. The age-dependency, significant contributions from environmental factors such as diet and exercise, and inherent moment-to-moment variability complicate the identification of the genes contributing to the development of hypertension. Although genetic abnormalities may have moderate effects, the physiologic pathways involving these genes have redundant compensating mechanisms to bring the system back into equilibrium. This has the effect of reducing or completely masking the initial genetic defects, one of the hypothesized reasons for the small genetic effects found by the recent genome-wide association studies. This review article discusses the concept of initiators versus compensators in the context of finding genes related to hypertension development. A brief review is provided of some key genes found to be associated with hypertension, including the genes identified from the nine genome-wide association studies published to date.
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Affiliation(s)
- Steven C Hunt
- Cardiovascular Genetics Division, Department of Internal Medicine, University of Utah, Salt Lake City, UT 84108, USA.
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Genotype-phenotype analysis of angiotensinogen polymorphisms and essential hypertension: the importance of haplotypes. J Hypertens 2010; 28:65-75. [PMID: 19770777 DOI: 10.1097/hjh.0b013e328332031a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVES To better understand the relationship between angiotensinogen (AGT) genetic variation and essential hypertension, AGT genotypes and haplotypes were tested for association with hypertensive endophenotypes and essential hypertension. METHODS Two hundred and fifty-six Hypertensive Pathotype (HyperPATH)/Specialized Center of Research (SCOR) cases and 126 controls were genotyped for 24 single-nucleotide polymorphisms (SNPs) in the AGT gene. SNPs and AGT haplotypes were tested for association with plasma AGT, renal plasma flow (RPF), and essential hypertension. RESULTS New associations between essential hypertension, plasma AGT, and RPF are reported for alleles -1178G, 6066A, 6152A, 6233C, and 12822C. The maximum odds ratio for association of hypertension and AGT genetic variation was 2.3 [95% confidence interval (CI) 1.5-3.8; P < 0.0003] for allele 6233C. Previous associations for -1074T, -532T, -217A, -6A, and 4072C are confirmed (P < 0.05). Sodium depletion enhances associations between AGT SNPs and plasma AGT. Most individually associated SNPs, including -6A and 4072C, are found on a common complete AGT haplotype, H4 (frequency = 0.09). Individuals with haplotype H4 have significantly higher plasma AGT and reduced RPF (P < 0.003 and P < 0.0002, respectively). Other common haplotypes are not associated with increased plasma AGT levels in this data set despite the presence of the -6A and 4072C alleles, suggesting that AGT haplotype H4 is more predictive of elevated plasma AGT than is -6A or 4072C. CONCLUSION This study demonstrates the importance of analyzing haplotypes in addition to single genotypes in association studies. By demonstrating the dependence of AGT associations on sodium depletion status, it helps to explain previous conflicting association results.
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Abstract
1. Initial attempts to inhibit renin in humans have faced numerous difficulties. Molecular modelling and X-ray crystallography of the active site of renin have led to the development of new orally active renin inhibitors, such as aliskiren. 2. Aliskiren has a low bioavailability (between 2.6 and 5.0%) compensated by its high potency to inhibit renin (IC50: 0.6 nmol/L) and a long plasma half-life (23-36 h), which makes it suitable for once-daily dosing. 3. The once-daily administration of aliskiren to hypertensive patients lowers BP as strongly as standard doses of established angiotensin II type 1 (AT1) receptor blockers (losartan, valsartan, irbesartan), hydrochlorothiazide, angiotensin converting enzyme inhibitors (ramipril and lisinopril) or long acting calcium channel blockers (amlodipine). In combination therapy, aliskiren further decreases blood pressure when combined with either hydrochlorothiazide, amlodipine, irbesartan or ramipril. 4. The biochemical consequences of renin inhibition differ from those of angiotensin I-converting enzyme (ACE) inhibition and Ang II antagonism, particularly in terms of angiotensin profiles and interactions with the bradykinin-nitric oxide-cyclic guanosine monophosphate pathway and possibly the (pro)renin receptor. 5. Blockade of the renin angiotensin system (RAS) with ACE inhibitors, AT1 receptor blockers or a combination of these drugs has become one of the most successful therapeutic approaches in medicine. However, it remains unclear how to optimize RAS blockade to maximize cardiovascular and renal benefits. In this context, renin inhibition to render the RAS fully quiescent is a new possibility requiring further study.
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Carey RM. Pathophysiology of Primary Hypertension. Microcirculation 2008. [DOI: 10.1016/b978-0-12-374530-9.00020-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Baker M, Rahman T, Hall D, Avery PJ, Mayosi BM, Connell JMC, Farrall M, Watkins H, Keavney B. The C-532T polymorphism of the angiotensinogen gene is associated with pulse pressure: a possible explanation for heterogeneity in genetic association studies of AGT and hypertension. Int J Epidemiol 2007; 36:1356-62. [PMID: 17998241 DOI: 10.1093/ije/dym213] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Many previous studies have investigated whether there is an association between genotypes at the angiotensinogen (AGT) gene and hypertensive status, but few have incorporated quantitative data. Although meta-analyses support a possible effect of AGT variants on blood pressure (BP), substantial unexplained between-study heterogeneity has been observed. We hypothesized that a primary effect of AGT variants on arterial stiffness (and thus pulse pressure) might explain such heterogeneity, and tested for such an effect in a family study. METHODS We studied 1425 individuals from 248 families ascertained through a proband with essential hypertension. BP was measured using 24 h ambulatory monitoring, and polymorphisms of the AGT gene that had been previously associated with hypertension and/or plasma angiotensinogen levels were typed. Pulse pressure was used as a measurement of arterial stiffness. RESULTS We observed a highly significant association between genotypes at the AGT C-532T polymorphism and pulse pressure (p = 0.00006). Each T allele was associated with a 5% lower pulse pressure (that is, an additive effect). This resulted from opposing genotypic effects to (slightly) lower systolic BP and (slightly) elevate DBP. CONCLUSIONS These results suggest that genetic variation at the angiotensinogen locus may primarily affect arterial stiffness, and therefore pulse pressure. The heterogeneity between previous genetic studies of AGT and hypertension status could in part be explained by this finding, since case selection criteria based on systolic BP, diastolic BP, or both would result in different levels of selection for the -532T allele.
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Affiliation(s)
- Michelle Baker
- The Institute of Human Genetics, Newcastle University, UK
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Forman JP, Price DA, Stevanovic R, Fisher ND. Racial differences in renal vascular response to angiotensin blockade with captopril or candesartan. J Hypertens 2007; 25:877-82. [PMID: 17351382 DOI: 10.1097/hjh.0b013e32803cae1a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE We compared the renal vascular response to captopril and candesartan among nondiabetic, normotensive black and white participants to explore angiotensin-converting enzyme-independent generation of angiotensin II. METHODS Thirteen black individuals and 10 white individuals in low-salt balance were given captopril and candesartan on sequential study days, and the renal plasma flow responses to these agents were measured. RESULTS Consistent with our prior observations, white individuals demonstrated a strong, significant correlation between responses to these drugs (r = 0.78, P = 0.008) and a significantly greater increase in the renal plasma flow in response to candesartan compared with captopril (104.2 +/- 26.8 versus 52.4 +/- 24.3 ml/min per 1.73 m; P = 0.03). In black participants, however, no correlation between responses to captopril and to candesartan was observed (r = 0.22, P = 0.47) and there was no difference in the renal plasma flow response between the two drugs (90.4 +/- 13.0 versus 80.4 +/- 15.3 ml/min per 1.73 m; P = 0.59). The difference in the response to the two drugs was significantly higher among white participants compared with black participants (P = 0.03). CONCLUSION We confirmed the contribution of an angiotensin-converting enzyme-independent pathway for angiotensin II generation in the kidneys of nondiabetic, normotensive white, but not black, individuals.
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Affiliation(s)
- John P Forman
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
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Chamarthi B, Kolatkar NS, Hunt SC, Williams JS, Seely EW, Brown NJ, Murphey LJ, Jeunemaitre X, Williams GH. Urinary free cortisol: an intermediate phenotype and a potential genetic marker for a salt-resistant subset of essential hypertension. J Clin Endocrinol Metab 2007; 92:1340-6. [PMID: 17264181 DOI: 10.1210/jc.2006-2093] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Emerging evidence suggests a role for cortisol in essential hypertension, and preliminary reports indicate that urinary free cortisol (UFC) may be an intermediate phenotype. OBJECTIVES The objectives of this study were: 1) confirm bimodality of UFC, 2) assess whether UFC variations aggregate in hypertensive families, and 3) compare low-mode and high-mode UFC groups for distinguishing features. SUBJECTS/SETTING Subjects included 390 hypertensives and 166 normotensives from the general community. DESIGN/INTERVENTIONS Subjects had blood pressure and laboratory measurements on high- and low-salt diets. Familial aggregation was evaluated in 250 hypertensive siblings from 117 families. RESULTS Hypertensives had higher UFC than normotensives (P<0.001) and bimodal distribution of UFC (P<0.0001). Analyses were controlled for gender and dietary sodium, which are confounding determinants of UFC. Mean low-mode UFC (33.8+/-10.6 microg per 24 h) was similar to that of normotensives. The high mode, comprising 31.3% of hypertensives, had less change in mean arterial pressure between diets than the low mode (P=0.01) without any other significant differences. Observed proportions of concordance and discordance for UFC mode differed significantly from that expected (P<0.001). Observed concordance for the high mode was twice that expected, whereas for the low mode, it was similar to that expected by chance. Family membership explained a significant proportion of variance in UFC classification (P=0.027). UFC mode of one sibling was a significant predictor of the UFC mode of the other sibling [odds ratio 6.6, 95% confidence interval (2.4-18.0), P<0.001]. CONCLUSION High-mode UFC is an intermediate phenotype of hypertension associated with salt resistance and a strong familial component supporting heritability.
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Affiliation(s)
- Bindu Chamarthi
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital and Harvard Medical School, 221 Longwood Avenue, Boston, Massachusetts 02115, USA
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Handtrack C, Cordasic N, Klanke B, Veelken R, Hilgers KF. Effect of the angiotensinogen genotype on experimental hypertension in mice. J Mol Med (Berl) 2007; 85:343-50. [PMID: 17333097 DOI: 10.1007/s00109-007-0166-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2006] [Revised: 12/10/2006] [Accepted: 01/02/2007] [Indexed: 10/23/2022]
Abstract
Polymorphisms of the angiotensinogen (Agt) gene may affect blood pressure. We used a mouse model to test for the role of the Agt genotype in low-renin or high-renin forms of hypertension. Mice bearing one, two, three, or four copies of the Agt gene underwent renal artery clipping to induce high-renin two-kidney, one-clip renovascular hypertension (2K1C), or uninephrectomy, salt loading, and application of deoxycorticosterone-acetate (DOCA) pellets to induce low-renin mineralocorticoid hypertension. Appropriate control animals were also studied. Blood pressure was measured by tail cuff as well as by direct intra-arterial recordings. There was a small effect of the Agt genotype on baseline blood pressure before induction of hypertension. The extent of 2K1C hypertension was not affected by the genotype. In contrast, there was a marked gene-dose effect on DOCA-hypertension (21.2 mmHg over all genotypes). Treatment of DOCA mice with the angiotensin II type 1 receptor antagonist abolished the genotype effect on blood pressure and left ventricular hypertrophy. There was a trend towards less suppression of endogenous aldosterone by DOCA treatment with increasing number of Agt gene copies. We conclude that the Agt genotype exerts a marked effect on blood pressure in a low-renin form of hypertension but no effect in the face of stimulated renin, at least in mice.
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Affiliation(s)
- Claudia Handtrack
- Department of Nephrology and Hypertension, University of Erlangen-Nuremberg, Erlangen, Germany
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Gumieniak O, Perlstein TS, Williams JS, Hopkins PN, Brown NJ, Raby BA, Williams GH. Ala92 type 2 deiodinase allele increases risk for the development of hypertension. Hypertension 2007; 49:461-6. [PMID: 17224473 DOI: 10.1161/01.hyp.0000256295.72185.fd] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Accumulating evidence suggests that genes of the hypothalamic-pituitary-thyroid pathway influence susceptibility to hypertension. Type 2 iodothyronine deiodinase is responsible for the conversion of thyroxine to tri-iodothyronine for use in peripheral tissues. The present study evaluated whether a type 2 iodothyronine deiodinase nonsynonymous polymorphism, threonine 92 to alanine (Thr92Ala), is a determinant of hypertension susceptibility. A total of 372 euthyroid subjects were genotyped for Thr92Ala polymorphism using the Sequenom MassARRAY platform. Associations with hypertension and hypertension-related intermediate phenotypes were performed with generalized estimating equations. Type 2 iodothyronine deiodinase Thr92Ala allele frequencies differed significantly between hypertensive and normotensive subjects, with an excess of Ala92 carriers in hypertensive compared with normotensive subjects (64.8% versus 47.1%; P=0.011). Adjusted for age, gender and race, the estimated odds ratio for hypertension in Ala92 allele carriers compared with Thr92 homozygotes was 2.11 (95% CI: 1.15 to 3.89). Among euthyroid adults, the common Ala92 allele of the type 2 iodothyronine deiodinase increases risk for the development of hypertension. These data support an important role for genetic variation in the hypothalamic-pituitary-thyroid pathway in influencing susceptibility to hypertension.
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Affiliation(s)
- Olga Gumieniak
- Endocrinology, Diabetes, and Hypertension Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Mass 02115, USA
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Pojoga L, Kolatkar NS, Williams JS, Perlstein TS, Jeunemaitre X, Brown NJ, Hopkins PN, Raby BA, Williams GH. β-2 Adrenergic Receptor Diplotype Defines a Subset of Salt-Sensitive Hypertension. Hypertension 2006; 48:892-900. [PMID: 17015767 DOI: 10.1161/01.hyp.0000244688.45472.95] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Two genetic variants of the beta-2 adrenergic receptor, 46G>A and 79C>G, affect agonist-mediated receptor downregulation and vascular reactivity. We determined whether these variants were associated with hypertension, per se, blood pressure response to dietary sodium, 2 forms of salt-sensitive hypertension (low renin and nonmodulation), and the activity of the renin-angiotensin-aldosterone system. Included are 280 hypertensive and 65 normotensive white subjects who had the 2 beta-2 adrenergic receptor genotypes available. Of all subjects, 171 hypertensive and 48 normotensive subjects had complete data for intermediate phenotyping and blood pressure evaluation on high- and low-sodium balance. The beta-2 adrenergic receptor variants were not associated with hypertension per se. However, among hypertensive subjects, the change (from low to high sodium balance) in mean arterial pressure differed significantly by genotype and by diplotype. Compared with all of the other diplotypes combined, 46AA/79CC was associated with a greater change in blood pressure. Furthermore, this diplotype was associated with low-renin (LR) hypertension (identifying 32% of the LR hypertensives), higher plasma aldosterone, and lower plasma renin and serum potassium levels. In conclusion, the 46AA/79CC diplotype is associated with greater blood pressure response to dietary sodium and higher odds of LR hypertension. We propose that the mechanism for the observed association is inadequate suppression of aldosterone with salt intake, implicating the beta-2 adrenergic receptor in the regulation of aldosterone secretion. This hypothesis was confirmed in isolated glomerulosa cells, where beta-2 adrenergic receptor stimulation increased aldosterone secretion, whereas blockade reduced the stimulated aldosterone response. Importantly, this association could only be detected with an intermediate and not a distant phenotype.
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Affiliation(s)
- Luminita Pojoga
- Brigham and Women's Hospital, Division of Endocrinology, Diabetes, and Hypertension, 221 Longwood Ave, Boston, MA 02115, USA
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Abstract
The goal of this essay is to examine the evidence relating salt intake to blood pressure in humans. Despite studies involving many thousands of subjects and patients performed in many hundreds of centers the issue remains controversial-indeed far more controversial than seems appropriate. There is little disagreement that in some animal models and in some patients with hypertension salt intake can exert a rather substantial influence. There is more controversy on the responsible mechanisms. The greatest controversy, by far, involves whether or not policy should involve a mandatory reduction in salt intake in all members of the community. The available evidence shows that the influence of salt intake is too inconsistent and generally too small to mandate policy decisions at the community level. At the level of the individual patient and that patient's physician, it is important to recognize that salt intake can make a substantial contribution to hypertension. That contribution is more likely if the patient is old rather than young, obese rather than lean, black rather than white, has diabetes mellitus with hypertension, or has evidence of renal injury. Unfortunately, tools for assessing the sodium and chloride intake in the individual and for assessing its contribution to BP in the individual are inadequate. On the bright side, prognosis is improved substantially by the array of antihypertensive drugs available today.
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Affiliation(s)
- Norman K Hollenberg
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical Center, Boston, MA 02115, USA.
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Abstract
Nonmodulation is a process in which there is a disorder in angiotensin-dependent control of the renal circulation and adrenal aldosterone release. The abnormalities are associated with an inability to handle a sodium load and salt-sensitive hypertension. All of the features are corrected by angiotensin-converting enzyme inhibition. A striking family history of hypertension and concordance of responses to angiotensin II in sibling pairs have suggested a familial factor. Genes governing renin substrate (angiotensinogen) production showed gene polymorphisms in nonmodulators. As nonmodulation occurs in approximately 40% of patients with essential hypertension, clearly other genes must contribute.
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Perlstein TS, Gumieniak O, Hopkins PN, Murphey LJ, Brown NJ, Williams GH, Hollenberg NK, Fisher NDL. Uric acid and the state of the intrarenal renin-angiotensin system in humans. Kidney Int 2005; 66:1465-70. [PMID: 15458439 DOI: 10.1111/j.1523-1755.2004.00909.x] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Experimental hyperuricemia is marked by an activated intrarenal renin-angiotensin system (RAS). The renal vascular response to exogenous angiotensin II (Ang II) provides an indirect measure of intrarenal RAS activity. We tested the hypothesis that the serum uric acid concentration predicts the renal vascular response to Ang II. METHODS A total of 249 subjects in high sodium balance had the renal plasma flow (RPF) response to Ang II measured. Para-aminohippuric acid (PAH) clearance was used to estimate RPF. Multivariable regression analysis determined if the serum uric acid concentration independently predicts the RPF response to Ang II. Variables considered included age, gender, race, body mass index (BMI), hypertension status, blood pressure, basal RPF, creatinine clearance, serum insulin, serum glucose, serum high-density lipoprotein (HDL), serum triglycerides, and plasma renin activity (PRA). RESULTS Uric acid concentration negatively correlated with the RPF response to Ang II (r=-0.37, P < 0.001). In univariate analysis, age, BMI, hypertension, triglycerides, and blood pressure were negatively associated, and basal RPF, HDL, and female gender were positively associated with the RPF response to Ang II. In multivariable analysis, serum uric acid concentration independently predicted the RPF response to Ang II (beta=-5.3, P < 0.001). CONCLUSION Serum uric acid independently predicted blunted renal vascular responsiveness to Ang II, consistent with results from experimental hyperuricemia showing an activated intrarenal RAS. This could be due to a direct effect of uric acid or reflect a more fundamental renal process. These data may have relevance to the association of uric acid with risk for hypertension and nephropathy.
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Affiliation(s)
- Todd S Perlstein
- Endocrinology, Diabetes and Hypertension Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
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Harrap SB. Blood Pressure Genetics. Hypertension 2005. [DOI: 10.1016/b978-0-7216-0258-5.50095-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Miller JA, Scholey JW. The impact of renin-angiotensin system polymorphisms on physiological and pathophysiological processes in humans. Curr Opin Nephrol Hypertens 2004; 13:101-6. [PMID: 15090866 DOI: 10.1097/00041552-200401000-00014] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW The renin-angiotensin system plays a central role in health and disease but the determinants of renin-angiotensin system activity have not been fully elucidated. Physiologic genomics continues to be an active area of research that emphasizes definition of phenotype and clarification of non-genomic factors that influence the genotype-phenotype correlation. A common variant of the angiotensinogen gene (T235) predicts elevated levels of circulating angiotensinogen, and polymorphisms of this gene have been linked to physiologic responses and to the risk of cardiovascular disease. The angiotensin-converting-enzyme gene insertion/deletion polymorphism, although not considered functional, has been associated with physiologic responses and disease risk in hypertension and diabetes. A polymorphism of the angiotensin type 1 receptor gene, A1166C, has been the focus of several physiologic studies. These authors will focus on mechanistic studies in normal humans and those with diabetes mellitus or hypertension that examine the impact of these polymorphisms on physiologic responses. RECENT FINDINGS Recent studies provide divergent results. Many have shown that mediating factors interfere with the genotype-phenotype correlation. Studies in normal individuals and in those with diabetes mellitus have shown that sodium status and glycemia can alter the impact of genotype. In individuals with essential hypertension, the pathway between genotype and physiology can be disrupted by gender and/or race. SUMMARY Divergent results in many studies may be attributable to various non-genomic and environmental influences on the pathway between gene polymorphism and physiology. Clarification of these factors should allow a better understanding of genotype-phenotype correlation.
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Kuznetsova T, Staessen JA, Reineke T, Olszanecka A, Ryabikov A, Tikhonoff V, Stolarz K, Bianchi G, Casiglia E, Fagard R, Brand-Herrmann SM, Kawecka-Jaszcz K, Nikitin Y, Brand E. Context-dependency of the relation between left ventricular mass and AGT gene variants. J Hum Hypertens 2004; 19:155-63. [PMID: 15483663 DOI: 10.1038/sj.jhh.1001793] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the European Project on Genes in Hypertension (EPOGH), we investigated in three populations to what extent in a family-based study, left ventricular mass (LVM) was associated with the C-532T and G-6A polymorphisms in the angiotensinogen (AGT) gene. We randomly recruited 221 nuclear families (384 parents and 440 offspring) in Cracow (Poland), Novosibirsk (Russia), and Mirano (Italy). Echocardiographic LVM was indexed to body surface area, adjusted for covariables, and subjected to multivariate analyses, using generalized estimating equations and quantitative transmission disequilibrium tests in a population-based and family-based approach, respectively. We found significant differences between the two Slavic centres and Mirano in left ventricular mass index (LVMI) (94.9 vs 80.4 g/m2), sodium excretion (229 vs 186 mmol/day), and the prevalence of the AGT -6A (55.7 vs 40.6%) and -532T (16.8 vs 9.4%) alleles. In population-based as well as in family-based analyses, we observed positive associations of LVMI and mean wall thickness (MWT) with the -532T allele in Slavic, but not in Italian male offspring. Furthermore, in Slavic male offspring, LVMI and MWT were significantly higher in carriers of the -532T/-6A haplotype than in those with the -532C/-6G or -532C/-6A allele combinations. In women, LVMI was neither associated with single AGT gene variants nor with the haplotypes (0.19 < P <0.98). In Slavic offspring carrying the AGT -532C/-6G or -532C/-6A haplotypes, LVMI significantly increased with higher sodium excretion (+3.5 g/m2/100 mmol; P=0.003), whereas such association was not present in -532T/-6A haplotype carriers (P-value for interaction 0.04). We found a positive association between LVMI and the AGT -532T allele due to increased MWT. This relation was observed in Slavic male offspring. It was therefore dependent on gender, age and ecogenetic context, and in addition it appeared to be modulated by the trophic effects of salt intake on LVM.
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Affiliation(s)
- T Kuznetsova
- Study Coordinating Centre, Hypertension and Cardiovascular Rehabilitation Unit, Department of Molecular and Cardiovascular Research, Campus Gasthuisberg, University of Leuven, Belgium
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van Onna M, Kroon AA, Houben AJHM, Koster D, Zeegers MPA, Henskens LHG, Plat AW, Stoffers HEJH, de Leeuw PW. Genetic Risk of Atherosclerotic Renal Artery Disease. Hypertension 2004; 44:448-53. [PMID: 15326089 DOI: 10.1161/01.hyp.0000141440.02210.da] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
It is largely unknown to what extent genetic abnormalities contribute to the development of atherosclerotic renal artery disease. Among the potential candidate genes, those of the renin-angiotensin system and the endothelial nitric oxide synthase (eNOS) rank high because of their importance in the atherosclerotic process. We investigated the association of polymorphisms in these genes (the angiotensinogen Met235Thr, the angiotensin-converting enzyme insertion/deletion, the angiotensin II type-1 receptor A1166C, and the eNOS Glu298Asp) with the presence or absence of atherosclerotic renovascular disease in 456 consecutive hypertensive patients referred for renal angiography on the suspicion of renovascular hypertension. Nondiseased normotensive (n=200) and hypertensive (n=154) patients from a family practice served as external controls. Renal artery disease was present in 30% of our angiography group. The Asp allele of the eNOS Glu298Asp polymorphism was associated with atherosclerotic renal artery stenosis with an odds ratio of 1.44 (95% confidence interval 1.00 to 2.09) versus hypertensives with angiographically proven patent arteries, of 1.89 (1.24 to 2.87) versus hypertensive family practice controls, and of 2.09 (1.29 to 3.38) versus normotensive family practice controls. However, this allele also differed significantly between patients with patent renal arteries and normotensive and hypertensive controls. No differences were found with respect to the other genetic polymorphisms. We hypothesize that the Asp allele of the Glu298Asp polymorphism may predispose to the development of atherosclerotic lesions but that renal artery involvement depends on other factors, also.
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Affiliation(s)
- Marieke van Onna
- Department of Internal Medicine, University Hospital Maastrichtand Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands
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Gumieniak O, Perlstein TS, Hopkins PN, Brown NJ, Murphey LJ, Jeunemaitre X, Hollenberg NK, Williams GH. Thyroid function and blood pressure homeostasis in euthyroid subjects. J Clin Endocrinol Metab 2004; 89:3455-61. [PMID: 15240631 DOI: 10.1210/jc.2003-032143] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Overt and subclinical hypothyroidism are associated with increased systemic vascular resistance and hypertension. We examined the relationship between thyroid function and blood pressure homeostasis in euthyroid individuals. A total of 284 subjects (68% hypertensive) consumed high- (200 mmol) and low- (10 mmol) sodium diets, and their blood pressure responses were assessed as percentage change in the mean arterial pressure (MAP). p-Aminohippuric acid clearance was used to estimate effective renal plasma flow. Renal vascular resistance (RVR) was calculated as MAP divided by effective renal plasma flow. Serum free T(4) index (FTI) was lower (P < 0.0001) and TSH was higher (P = 0.046) in hypertensive compared with normotensive subjects independent of other baseline characteristics. FTI (beta = -1.51, P < 0.0001), baseline MAP, and race independently predicted MAP salt sensitivity. The FTI relationship with salt sensitivity adjusted for baseline MAP and race was similar among normotensive (beta = -1.42, P = 0.008) and hypertensive subjects (beta = -1.66, P = 0.0001). FTI correlated negatively with high- (P = 0.0001) and low- (P = 0.008) salt RVR, whereas TSH correlated positively with high- (P = 0.016) and low- (P = 0.012) salt RVR independent of age, gender, race, and body mass index. We have found that FTI is lower and TSH is higher in hypertensive compared with normotensive euthyroid subjects and that FTI independently predicts blood pressure salt sensitivity. These data show that the influence of thyroid function on blood pressure homeostasis extends into euthyroid range and likely reflects the action of thyroid hormone on peripheral vasculature.
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Affiliation(s)
- Olga Gumieniak
- Endocrinology, Diabetes and Hypertension Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, RFB-2, Boston, MA 02115, USA
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Affiliation(s)
- Chris Winkelman
- Chris Winkelman is an assistant professor of nursing at Case Western Reserve University, Cleveland, Ohio, and a staff nurse in the trauma and critical care float pool at Metro-Health Medical Center in Cleveland. She was a fellow at the summer genetics institute at the National Institutes of Health in 2001
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Guo Y, Mascareno E, Siddiqui MAQ. Distinct components of Janus kinase/signal transducer and activator of transcription signaling pathway mediate the regulation of systemic and tissue localized renin-angiotensin system. Mol Endocrinol 2004; 18:1033-41. [PMID: 14726487 DOI: 10.1210/me.2003-0231] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In an attempt to demonstrate the linkage between the Janus kinase (Jak)/signal transducer and activator of transcription (STAT) signaling and the activity of the systemic or local renin-angiotensin system in vivo, we produced transgenic mice harboring angiotensinogen (ANG) promoter containing the wild-type or mutant STAT target site (St-domain) fused to the luciferase reporter. The ANG-promoter-driven luciferase expression was dependent upon phosphorylation of Jak2, as administration of tyrphostin AG490, a potent inhibitor of Jak2, down-regulated the ANG promoter activity and abolished the stimulated endogenous ANG mRNA level in the liver. Administration of angiotensin II peptide to the mice resulted in prominent expression of luciferase in the liver and heart of animals containing wild type St-domain, but not in transgenes with mutant St-domain. Angiotensin II-induced signaling caused activation of STAT proteins in the liver (systemic), the pattern of which was distinct from that in the heart (local). The inducible expression of ANG promoter appears to be mediated by physical association of p300 with STAT 5B in liver and STAT 3 and STAT 5A in heart. Taken together, these results point to the differences in signaling mechanisms in the circulating and localized renin-angiotensin system and identify at least two molecular steps, the tyrosyl phosphorylation of Jak2 and the STAT/St-domain interaction, as pivotal in the regulation of ANG gene transcription.
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Affiliation(s)
- Yueling Guo
- Department of Anatomy and Cell Biology, Center for Cardiovascular and Muscle Research, State University of New York Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
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Abstract
Defining the genetic basis of essential hypertension is most informative when the blood pressure regulation is correlated with physiologic mechanisms, e.g., responses of the renin-angiotensin aldosterone system (RAAS) in hypertensive subjects. The aldosterone response to angiotensin II (Ang II) on a low salt diet is influenced by gender, plasma renin activity, and most significantly, familial resemblance, but only in males and in post-menopausal females. There is familial aggregation of low-renin hypertension, no association with candidate genes of the RAAS, but, a highly significant association with polymorphisms in the alpha-adducin gene. Finally, angiotensinogen (AGT) genotype effects renal and adrenal responses to Ang II in patients with hypertension. These results strongly suggest that in contrast to population-based studies that use hypertension as the phenotype, classifying patients by the variability in physiologic, mechanistic traits enhances the probability of identifying the genetic factors influencing a rise in blood pressure.
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Affiliation(s)
- Gordon H Williams
- Endocrinology, Diabetes and Hypertension Division, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, RFB-2, Boston, MA 02115, USA.
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Affiliation(s)
- Paul N Hopkins
- Cardiovascular Genetics, University of Utah, Salt Lake City 84108, USA
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Kosachunhanun N, Hunt SC, Hopkins PN, Williams RR, Jeunemaitre X, Corvol P, Ferri C, Mortensen RM, Hollenberg NK, Williams GH. Genetic determinants of nonmodulating hypertension. Hypertension 2003; 42:901-8. [PMID: 14530292 DOI: 10.1161/01.hyp.0000095615.83724.82] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We sought to determine whether genes of the renin-angiotensin-aldosterone system can predict the nonmodulating intermediate phenotype in essential hypertension. Aldosterone responses to angiotensin II were assessed in 298 subjects with hypertension. Subjects were genotyped at the angiotensinogen M235T, angiotensin-converting enzyme I/D, aldosterone synthase C-344 T, renin, angiotensin II type 1 receptor, and adducin loci. The data were analyzed by Student t test, ANOVA, stepwise linear regression and general linear model or GENMOD regression techniques, and chi2 analysis odds ratios (ORs). Aldosterone response varied by genotype for angiotensin and aldosterone synthase but not for the other loci. The combination of angiotensinogen 235 TT and angiotensin-converting enzyme DD showed further reduction (P=0.0377) when compared with angiotensinogen 235 TT alone, an example of genetic epistasis. When the subject was required also to possess the CYP11B2 -344 TT genotype, there was a further substantial reduction. Of these 3 loci, only angiotensinogen 235 TT significantly increased the OR of predicting the nonmodulating hypertensive phenotype (OR, 2.00; 95% confidence interval, 1.152 to 3.51). However, when angiotensin-converting enzyme DD was combined with angiotensinogen 235 TT, the OR nearly doubled to 3.74, with a further increase to 5.36-fold when the subject possessed all 3 genotypes. Thus, the angiotensinogen, angiotensin-converting enzyme, and aldosterone synthase genotypes identified individuals with the nonmodulating phenotype with an increasing degree of fidelity. For this subclass of essential hypertension, it is likely that genotyping can be substituted for complex phenotyping for therapeutic and preventive decision making.
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Affiliation(s)
- Natapong Kosachunhanun
- Endocrine-Hypertension Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass 02115, USA
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Abstract
Hypertension is a frequent, chronic, age-related disorder, which often entails debilitating cardiovascular and renal complications. Blood pressure is usually noted in combination with other cardiovascular risk factors. Diagnosis of hypertension increasingly relies on automated techniques of blood pressure measurement. The pathophysiology of essential hypertension depends on the primary or secondary inability of the kidney to excrete sodium at a normal blood pressure. The central nervous system, endocrine factors, the large arteries, and the microcirculation also have roles in the disorder. Although monogenic forms of blood pressure dysregulation exist, hypertension mostly arises as a complex quantitative trait that is affected by varying combinations of genetic and environmental factors. Non-pharmacological strategies can reduce blood pressure. Antihypertensive drug treatment diminishes the complications of hypertension. The concept that a few major genes will provide the final clue to the pathogenesis of essential hypertension is an oversimplification that contradicts the heterogeneous nature of this disorder. Further integration of genetic, molecular, clinical, and epidemiological research could disclose subsets of patients in whom specific combinations of genetic and environmental factors raise blood pressure, and might lead to more individualised treatment.
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Hurwitz S, Fisher ND, Ferri C, Hopkins PN, Williams GH, Hollenberg NK. Controlled analysis of blood pressure sensitivity to sodium intake: interactions with hypertension type. J Hypertens 2003; 21:951-9. [PMID: 12714870 DOI: 10.1097/00004872-200305000-00020] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The contribution of salt intake to the pathogenesis of hypertension holds longstanding interest. Recent studies employed the sensitivity of blood pressure (BP) to salt intake as an intermediate phenotype. The validity of this approach relative to the homogeneity of sodium-sensitive hypertension was investigated while simultaneously controlling multiple putative factors. METHODS Blood pressure responses to shifts in salt intake were measured in 274 individuals with essential hypertension in steady-state sodium balance on high (200 mEq) and low (10 mEq) sodium intakes. Univariate and multivariate analyses predicted systolic and diastolic sodium sensitivity based on interactions among demographic factors (age, gender, race, body mass index) and hypertensive type [low-renin (LR), modulator (M), non-modulator (NM)]. RESULTS The influence of hypertension type on systolic salt sensitivity (SSS) depended on gender (P = 0.03). In females, highest SSS was in LR (21, 14, 13 mmHg for LR, M, NM, P = 0.02), while in males highest SSS was in NM (11, 10, 16 mmHg for LR, M, NM, P = 0.07). Age predicted SSS without interacting with other factors, producing a 2.4 mmHg increase per decade (P = 0.02). Hypertension type affected diastolic salt sensitivity (DSS) (P = 0.002) without interacting with other factors. M had less DSS (6 mmHg) than LR (9 mmHg) and NM (11 mmHg) (P < 0.01). CONCLUSIONS For subjects in sodium balance, the distributions of SSS and DSS were unimodal and the mechanisms mediating SSS and DSS were different. Controlling for multiple demographic factors, at least two hypertensive types have largest BP responses to sodium intake, reducing the usefulness of blood pressure sensitivity to salt intake as an intermediate phenotype.
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Affiliation(s)
- Shelley Hurwitz
- Departments of Medicine and Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, Massachusetts 02115, USA.
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Abstract
PURPOSE OF REVIEW Defective transduction of the dopamine receptor signal in the kidney has been shown to be important in the pathogenesis of hypertension This review will discuss the genetic mechanism for the defective renal dopaminergic function and the interaction with other gene variant products in the pathogenesis of salt sensitivity and essential hypertension. RECENT FINDINGS Single nucleotide polymorphisms of G protein-coupled receptor kinase type 4 (GRK4) phosphorylate, desensitize, and diminish the inhibitory action of D receptors on sodium transport in the kidney. Inhibition of GRK4 expression normalizes renal proximal tubule D receptor function in humans and rodents and ameliorates the hypertension in genetically hypertensive rats. Expression of the GRK4 variant, GRK4gammaA142V, produces hypertension and impairs the natriuretic effect of D receptor stimulation in mice. In humans, GRK4 single nucleotide polymorphisms are associated with essential hypertension, particularly salt sensitive hypertension. The prediction of the hypertensive phenotype is most accurate when elements of the renin-angiotensin system and GRK4 are included in the analysis. SUMMARY GRK4 single nucleotide polymorphisms, by preventing the natriuretic function of the dopaminergic system and by allowing the antinatriuretic function of angiotensin II type 1 receptors to predominate, may be responsible for salt sensitivity. Hypertension develops with additional perturbations caused by the variants of other genes (e.g., alpha-adducin, angiotensin converting enzyme, angiotensinogen, angiotensin II type 1 receptor, aldosterone synthase, 11beta-hydroxysteroid dehydrogenase type 2), the quantitative interaction of which may vary depending upon the genetic background.
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Affiliation(s)
- Pedro A Jose
- Georgetown University Medical Center, Washington, DC 20007, USA.
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Hayden PS, Iyengar SK, Schelling JR, Sedor JR. Kidney disease, genotype and the pathogenesis of vasculopathy. Curr Opin Nephrol Hypertens 2003; 12:71-8. [PMID: 12496669 DOI: 10.1097/00041552-200301000-00012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
PURPOSE OF REVIEW The two leading causes of end-stage renal disease in the United States are diabetes mellitus and hypertensive nephrosclerosis, accounting for over two-thirds of all cases. In many patients both diseases are associated with small- and large-vessel disease, commonly attributed to hypertension or accelerated atherosclerosis. Recent investigations, however, have suggested that renal large-vessel and microvascular disease may be independent contributors to progressive kidney failure. RECENT FINDINGS Although genes have not been definitely linked to renal vascular disease, population- and family-based epidemiology of kidney disease, segregation analysis of Pima and Caucasian families in which diabetic nephropathy is clustered, and the positional cloning of genes responsible for rare, familial glomerulosclerosis syndromes support the hypothesis that genes regulate the pathogenesis of renal disease. This review highlights developments in our current understanding of vasculopathy and its role in renal disease, and it summarizes evidence suggesting that genetic determinants for the vascular phenotype are associated with common causes of chronic renal failure. SUMMARY With the application of genomics and proteomics methodologies to drug discovery, the identification of renal susceptibility genes should identify new mechanisms of progressive renal disease pathogenesis and generate novel target molecules for the treatment of kidney disease.
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Affiliation(s)
- Patrick S Hayden
- Department of Medicine, School of Medicine, Case Western Reserve University, and Rammelkamp Center for Research and Education, MetroHealth Medical Center, Cleveland, Ohio 44109-1998, USA
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Cheng F, Shen J, Luo X, Jiang H, Chen K. Steered molecular dynamics simulations on the "tail helix latch" hypothesis in the gelsolin activation process. Biophys J 2002; 83:753-62. [PMID: 12124262 PMCID: PMC1302184 DOI: 10.1016/s0006-3495(02)75206-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The molecular basis of the "tail helix latch" hypothesis in the gelsolin activation process has been studied by using the steered molecular dynamics simulations. In the present nanosecond scale simulations, the tail helix of gelsolin was pulled away from the S2 binding surface, and the required forces were calculated, from which the properties of binding between the tail helix and S2 domain and their dynamic unbinding processes were obtained. The force profile provides a detailed rupture mechanism that includes six major unbinding steps. In particular, the hydrogen bonds formed between Arg-207 and Asp-744 and between Arg-221 and Leu-753 are of the most important interaction pairs. The two hydrogen bond "clamps" stabilize the complex. The subsequent simulation on Arg-207-Ala (R207A) mutation of gelsolin indicated that this mutation facilitates the unbinding of the tail helix and that the contribution of the hydrogen bond between Arg-207 and Asp-744 to the binding is more than 50%, which offers a new clue for further mutagenesis study on the activation mechanism of gelsolin. Surrounding water molecules enhance the stability of the tail helix and facilitate the rupture process. Additionally, temperature also has a significant effect on the conformation of the arginine and arginine-related interactions, which revealed the molecular basis of the temperature dependence in gelsolin activation.
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Affiliation(s)
- Feng Cheng
- Center for Drug Discovery and Design, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 294 Taiyuan Road, Shanghai 200031, Peoples Republic of China
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