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Perla S, Kumar A. Epigenetic and transcriptional regulation of the human angiotensinogen gene by high salt. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.22.568343. [PMID: 38045346 PMCID: PMC10690268 DOI: 10.1101/2023.11.22.568343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Hypertension is caused by a combination of genetic and environmental factors. Angiotensinogen (AGT) is a component of RAAS, that regulates blood pressure. The human angiotensinogen (hAGT) gene has -6A/-6G polymorphism and -6A variant is associated with human hypertension. In this study, we have investigated the epigenetic regulation of the hAGT. To understand transcriptional regulation of the hAGT, we have made transgenic animals containing -6A. We show that HS affects DNA methylation and modulates transcriptional regulation of this gene in liver and kidney. High salt (HS) increases hAGT gene expression in -6A TG mice. We have observed that the number of CpG sites in the hAGT promoter is decreased after HS treatment. In the liver, seven CpG sites are methylated whereas after HS treatment, only three CpG sites remain methylated. In the kidney, five CpG sites are methylated, whereas after HS treatment, only three CpG sites remain methylated. These results suggest that HS promotes DNA demethylation and increasing AGT gene expression. RT-PCR and immunoblot analysis show that hAGT gene expression is increased by HS. Chip assay has shown that transcription factors bind strongly after HS treatment. RNA-Seq identified differentially expressed genes, novel target genes associated with hypertension, top canonical pathways, upstream regulators. One of the plausible mechanisms for HS induced up-regulation of the hAGT gene is through IL-6/JAK/STAT3/AGT axis.
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Habeeb E, Aldosari S, Saghir SA, Cheema M, Momenah T, Husain K, Omidi Y, Rizvi SA, Akram M, Ansari RA. Role of Environmental Toxicants in the Development of Hypertensive and Cardiovascular Diseases. Toxicol Rep 2022; 9:521-533. [PMID: 35371924 PMCID: PMC8971584 DOI: 10.1016/j.toxrep.2022.03.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 03/17/2022] [Indexed: 12/12/2022] Open
Abstract
The incidence of hypertension with diabetes mellitus (DM) as a co-morbid condition is on the rise worldwide. In 2000, an estimated 972 million adults had hypertension, which is predicted to grow to 1.56 billion by 2025. Hypertension often leads to diabetes mellitus that strongly puts the patients at an increased risk of cardiovascular, kidney, and/or atherosclerotic diseases. Hypertension has been identified as a major risk factor for the development of diabetes; patients with hypertension are at two-to-three-fold higher risk of developing diabetes than patients with normal blood pressure (BP). Causes for the increase in hypertension and diabetes are not well understood, environmental factors (e.g., exposure to environmental toxicants like heavy metals, organic solvents, pesticides, alcohol, and urban lifestyle) have been postulated as one of the reasons contributing to hypertension and cardiovascular diseases (CVD). The mechanism of action(s) of these toxicants in developing hypertension and CVDs is not well defined. Research studies have linked hypertension with the chronic consumption of alcohol and exposure to metals like lead, mercury, and arsenic have also been linked to hypertension and CVD. Workers chronically exposed to styrene have a higher incidence of CVD. Recent studies have demonstrated that exposure to particulate matter (PM) in diesel exhaust and urban air contributes to increased CVD and mortality. In this review, we have imparted the role of environmental toxicants such as heavy metals, organic pollutants, PM, alcohol, and some drugs in hypertension and CVD along with possible mechanisms and limitations in extrapolating animal data to humans. Rising incidence of hypertension may be linked to chronic exposure with environmental toxicants. Urban lifestyle and alcohol intake may be responsible for increased incidence of hypertension among urbanites. Exposure with organic solvent, heavy metals and pesticides could also be contributing to the rise in blood pressure.
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Affiliation(s)
- Ehsan Habeeb
- Department of Pharmaceutical Sciences, College of Pharmacy, Health Professions Division, Nova Southeastern University, 3200S University Drive, Fort Lauderdale, FL 33200, USA
| | - Saad Aldosari
- Department of Pharmaceutical Sciences, College of Pharmacy, Health Professions Division, Nova Southeastern University, 3200S University Drive, Fort Lauderdale, FL 33200, USA
| | - Shakil A. Saghir
- The Scotts Company LLC, Marysville, OH 43041, USA
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Mariam Cheema
- Department of Pharmaceutical Sciences, College of Pharmacy, Health Professions Division, Nova Southeastern University, 3200S University Drive, Fort Lauderdale, FL 33200, USA
| | - Tahani Momenah
- Department of Pharmaceutical Sciences, College of Pharmacy, Health Professions Division, Nova Southeastern University, 3200S University Drive, Fort Lauderdale, FL 33200, USA
| | - Kazim Husain
- Department of Gastrointestinal Oncology (FOB-2), Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Yadollah Omidi
- Department of Pharmaceutical Sciences, College of Pharmacy, Health Professions Division, Nova Southeastern University, 3200S University Drive, Fort Lauderdale, FL 33200, USA
| | - Syed A.A. Rizvi
- Department of Pharmaceutical Sciences, School of Pharmacy, Hampton University, VA 23668, USA
| | - Muhammad Akram
- Department of Eastern Medicine and Surgery, Government College University Faisalabad, Faisalabad, Pakistan
| | - Rais A. Ansari
- Department of Pharmaceutical Sciences, College of Pharmacy, Health Professions Division, Nova Southeastern University, 3200S University Drive, Fort Lauderdale, FL 33200, USA
- Corresponding author.
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Mopidevi B, Sivankutty I, Hao S, Ferreri NR, Kumar A. Effects of intron conversion in the human CYP11B2 gene on its transcription and blood pressure regulation in transgenic mice. J Biol Chem 2020; 295:11068-11081. [PMID: 32540969 DOI: 10.1074/jbc.ra120.013047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 06/13/2020] [Indexed: 01/19/2023] Open
Abstract
The human cytochrome P450 family 11 subfamily B member 2 (hCYP11B2) gene encodes aldosterone synthase, the rate-limiting enzyme in the biosynthesis of aldosterone. In some humans, hCYP11B2 undergoes a unique intron conversion whose function is largely unclear. The intron conversion is formed by a replacement of the segment of DNA within intron 2 of hCYP11B2 with the corresponding region of the hCYP11B1 gene. We show here that the intron conversion is located in an open chromatin form and binds more strongly to the transcriptional regulators histone acetyltransferase P300 (p300), NFκB, and CCAAT enhancer-binding protein α (CEBPα). Reporter constructs containing the intron conversion had increased promoter activity on transient transfection in H295R cells compared with WT intron 2. We generated humanized transgenic (TG) mice containing all the introns, exons, and 5'- and 3'-flanking regions of the hCYP11B2 gene containing either the intron conversion or WT intron 2. We found that TG mice containing the intron conversion have (a) increased plasma aldosterone levels, (b) increased hCYP11B2 mRNA and protein levels, and (c) increased blood pressure compared with TG mice containing WT intron 2. Results of a ChIP assay showed that chromatin obtained from the adrenals of TG mice containing the intron conversion binds more strongly to p300, NFκB, and CEBPα than to WT intron 2. These results uncover a functional role of intron conversion in hCYP11B2 and suggest a new paradigm in blood pressure regulation.
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Affiliation(s)
| | - Indu Sivankutty
- Department of Pathology, New York Medical College, Valhalla, New York, USA
| | - Shoujin Hao
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
| | - Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
| | - Ashok Kumar
- Department of Pathology, New York Medical College, Valhalla, New York, USA
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Mopidevi B, Kaw MK, Sivankutty I, Jain S, Perla SK, Kumar A. A polymorphism in intron I of the human angiotensinogen gene ( hAGT) affects binding by HNF3 and hAGT expression and increases blood pressure in mice. J Biol Chem 2019; 294:11829-11839. [PMID: 31201268 DOI: 10.1074/jbc.ra119.007715] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 06/12/2019] [Indexed: 12/12/2022] Open
Abstract
Angiotensinogen (AGT) is the precursor of one of the most potent vasoconstrictors, peptide angiotensin II. Genome-wide association studies have shown that two A/G polymorphisms (rs2493134 and rs2004776), located at +507 and +1164 in intron I of the human AGT (hAGT) gene, are associated with hypertension. Polymorphisms of the AGT gene result in two main haplotypes. Hap-I contains the variants -217A, -6A, +507G, and +1164A and is pro-hypertensive, whereas Hap-II contains the variants -217G, -6G, +507A, and +1164G and does not affect blood pressure. The nucleotide sequence of intron I of the hAGT gene containing the +1164A variant has a stronger homology with the hepatocyte nuclear factor 3 (HNF3)-binding site than +1164G. Here we found that an oligonucleotide containing +1164A binds HNF3β more strongly than +1164G and that Hap-I-containing reporter gene constructs have increased basal and HNF3- and glucocorticoid-induced promoter activity in transiently transfected liver and kidney cells. Using a knock-in approach at the hypoxanthine-guanine phosphoribosyltransferase locus, we generated a transgenic mouse model containing the human renin (hREN) gene and either Hap-I or Hap-II. We show that transgenic animals containing Hap-I have increased blood pressure compared with those containing Hap-II. Moreover, the transcription factors glucocorticoid receptor, CCAAT enhancer-binding protein β, and HNF3β bound more strongly to chromatin obtained from the liver of transgenic animals containing Hap-I than to liver chromatin from Hap-II-containing animals. These findings suggest that, unlike Hap-II variants, Hap-I variants of the hAGT gene have increased transcription rates, resulting in elevated blood pressure.
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Affiliation(s)
| | - Meenakshi K Kaw
- Department of Physiology and Pharmacology, University of Toledo, Toledo, Ohio 43614
| | - Indu Sivankutty
- Department of Pathology, New York Medical College, Valhalla, New York 10595
| | - Sudhir Jain
- Department of Pathology, New York Medical College, Valhalla, New York 10595
| | - Sravan Kumar Perla
- Department of Pathology, New York Medical College, Valhalla, New York 10595
| | - Ashok Kumar
- Department of Pathology, New York Medical College, Valhalla, New York 10595
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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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Cuevas S, Villar VAM, Jose PA. Genetic polymorphisms associated with reactive oxygen species and blood pressure regulation. THE PHARMACOGENOMICS JOURNAL 2019; 19:315-336. [PMID: 30723314 PMCID: PMC6650341 DOI: 10.1038/s41397-019-0082-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 10/19/2018] [Accepted: 12/21/2018] [Indexed: 02/08/2023]
Abstract
Hypertension is the most prevalent cause of cardiovascular disease and kidney failure, but only about 50% of patients achieve adequate blood pressure control, in part, due to inter-individual genetic variations in the response to antihypertensive medication. Significant strides have been made toward the understanding of the role of reactive oxygen species (ROS) in the regulation of the cardiovascular system. However, the role of ROS in human hypertension is still unclear. Polymorphisms of some genes involved in the regulation of ROS production are associated with hypertension, suggesting their potential influence on blood pressure control and response to antihypertensive medication. This review provides an update on the genes associated with the regulation of ROS production in hypertension and discusses the controversies on the use of antioxidants in the treatment of hypertension, including the antioxidant effects of antihypertensive drugs.
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Affiliation(s)
- Santiago Cuevas
- Center for Translational Science, Children's National Health System, 111 Michigan Avenue, NW, Washington, DC, 20010, USA.
| | - Van Anthony M Villar
- Department of Medicine, Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, Walter G. Ross Hall, Suite 738, 2300 I Street, NW, Washington, DC, 20052, USA
| | - Pedro A Jose
- Department of Medicine, Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, Walter G. Ross Hall, Suite 738, 2300 I Street, NW, Washington, DC, 20052, USA
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Jain S, Rana A, Jain K, Perla SK, Puri N, Kumar A. Age-Related Expression of Human AT1R Variants and Associated Renal Dysfunction in Transgenic Mice. Am J Hypertens 2018; 31:1234-1242. [PMID: 30084918 DOI: 10.1093/ajh/hpy121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 07/27/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The contribution of single nucleotide polymorphisms in transcriptional regulation of the human angiotensin receptor type I (hAT1R) gene in age-related chronic pathologies such as hypertension and associated renal disorders is not well known. The hAT1R gene has single nucleotide polymorphisms in its promoter that forms 2 haplotypes (Hap), Hap-I and Hap-II. Hap-I of AT1R gene is associated with hypertension in Caucasians. We have hypothesized here that age will alter the transcriptional environment of the cell and will regulate the expression of hAT1R gene in a haplotype-dependent manner. This could likely make subjects with Hap-I increasingly susceptible to age-associated, AT1R-mediated complications. METHOD We generated transgenic (TG) mice with Hap-I and Hap-II. Adults (10-12 weeks) and aged (20-24 months) TG male mice containing either Hap-I or Hap-II were divided into 4 groups to study (i) the age-associated and haplotype-specific transcriptional regulation of hAT1R gene and (ii) their physiological relevance. RESULTS In aged animals, TG mice with Hap-I show increased expression of hAT1R and higher blood pressure (BP); suppression of antioxidant defenses (hemoxygenase, superoxide dismutase) and antiaging molecules (ATRAP, Klotho, Sirt3); increased expression of pro-inflammatory markers (IL-6, TNFα, CRP, NOX1); and increased insulin resistance. In vivo ChIP assay shows stronger binding of transcription factor USF2 to the chromatin of Hap-I mice. CONCLUSION Our results suggest that in aged animals, as compared with Hap-II, the TG mice with Hap-I overexpress hAT1R gene due to the stronger transcriptional activity, thus resulting in an increase in their BP and associated renal disorders.
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Affiliation(s)
- Sudhir Jain
- Department of Pathology, Basic Science Building, New York Medical College, Valhalla, New York, USA
| | - Anita Rana
- Department of Bioinformatics and Genomics, University of North Carolina, Charlotte, North Carolina, USA
| | - Kavita Jain
- Department of Pathology, Basic Science Building, New York Medical College, Valhalla, New York, USA
| | - Sravan K Perla
- Department of Pathology, Basic Science Building, New York Medical College, Valhalla, New York, USA
| | - Nitin Puri
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Ashok Kumar
- Department of Pathology, Basic Science Building, New York Medical College, Valhalla, New York, USA
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Jain S, Puri N, Rana A, Sirianni N, Mopidevi B, Kumar A. Metabolic Syndrome Induces Over Expression of the Human AT1R: A Haplotype-Dependent Effect With Implications on Cardio-Renal Function. Am J Hypertens 2018; 31:495-503. [PMID: 29036458 DOI: 10.1093/ajh/hpx176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 09/27/2017] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The transcriptional regulation of the human angiotensin receptor subtype 1 (AT1R) gene in pathophysiologies, like the metabolic syndrome, is poorly understood. The human AT1R gene has polymorphisms in its promoter that can be arranged in 2 haplotypes. Variants -810T, -713T, -214A, and -153A always occur together (Hap-I) and variants -810A, -713G, -214C, and -153G form Hap-II. We have hypothesized that high fat diet will alter cellular transcriptional milieu and increase hAT1R gene expression in a haplotype-dependent manner. This will set up an AT1R-mediated feed-forward loop promoting inflammation, oxidative stress, and hypertension in Hap-I mice. METHOD Since Hap-I of the human AT1R gene is associated with hypertension in Caucasians, we generated transgenic (TG) mice with Hap-I and Hap-II and studied the physiological significance of high fat diet (HFD) on haplotype specific gene expression. Animals were fed with HFD for 20 weeks followed by blood pressure (BP) analysis and collection of their tissues for molecular and biochemical studies. RESULTS After HFD treatment, as compared to Hap-II, TG mice with Hap-I show increased expression of hAT1R gene and higher BP; suppression of antioxidant defenses (HO1, SOD1) and increased expression of IL-6, TNFα, IL-1β, NOX1. In vivo ChIP assay has shown that transcription factors CEBPβ, STAT3, and USF bind more strongly to the chromatin obtained from Hap-I TG mice. CONCLUSIONS Taken together, our results suggest, that after HFD treatment, as compared to Hap-II, the TG mice with Hap-I overexpress the AT1R gene due to the stronger transcriptional activity, thus resulting in an increase in their BP.
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Affiliation(s)
- Sudhir Jain
- Department of Pathology, Basic Science Building, New York Medical College, Valhalla, New York, USA
| | - Nitin Puri
- Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Anita Rana
- Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Natalie Sirianni
- Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Brahmaraju Mopidevi
- Department of Pathology, Basic Science Building, New York Medical College, Valhalla, New York, USA
| | - Ashok Kumar
- Department of Pathology, Basic Science Building, New York Medical College, Valhalla, New York, USA
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Tiu AC, Bishop MD, Asico LD, Jose PA, Villar VAM. Primary Pediatric Hypertension: Current Understanding and Emerging Concepts. Curr Hypertens Rep 2017; 19:70. [PMID: 28780627 PMCID: PMC6314210 DOI: 10.1007/s11906-017-0768-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The rising prevalence of primary pediatric hypertension and its tracking into adult hypertension point to the importance of determining its pathogenesis to gain insights into its current and emerging management. Considering that the intricate control of BP is governed by a myriad of anatomical, molecular biological, biochemical, and physiological systems, multiple genes are likely to influence an individual's BP and susceptibility to develop hypertension. The long-term regulation of BP rests on renal and non-renal mechanisms. One renal mechanism relates to sodium transport. The impaired renal sodium handling in primary hypertension and salt sensitivity may be caused by aberrant counter-regulatory natriuretic and anti-natriuretic pathways. The sympathetic nervous and renin-angiotensin-aldosterone systems are examples of antinatriuretic pathways. An important counter-regulatory natriuretic pathway is afforded by the renal autocrine/paracrine dopamine system, aberrations of which are involved in the pathogenesis of hypertension, including that associated with obesity. We present updates on the complex interactions of these two systems with dietary salt intake in relation to obesity, insulin resistance, inflammation, and oxidative stress. We review how insults during pregnancy such as maternal and paternal malnutrition, glucocorticoid exposure, infection, placental insufficiency, and treatments during the neonatal period have long-lasting effects in the regulation of renal function and BP. Moreover, these effects have sex differences. There is a need for early diagnosis, frequent monitoring, and timely management due to increasing evidence of premature target organ damage. Large controlled studies are needed to evaluate the long-term consequences of the treatment of elevated BP during childhood, especially to establish the validity of the current definition and treatment of pediatric hypertension.
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Affiliation(s)
- Andrew C Tiu
- Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, 2300 I Street, N.W. Washington, DC, 20037, USA.
| | - Michael D Bishop
- Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, 2300 I Street, N.W. Washington, DC, 20037, USA
| | - Laureano D Asico
- Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, 2300 I Street, N.W. Washington, DC, 20037, USA
| | - Pedro A Jose
- Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, 2300 I Street, N.W. Washington, DC, 20037, USA
| | - Van Anthony M Villar
- Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, 2300 I Street, N.W. Washington, DC, 20037, USA
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Rana A, Jain S, Puri N, Kaw M, Sirianni N, Eren D, Mopidevi BR, Kumar A. The transcriptional regulation of the human angiotensinogen gene after high-fat diet is haplotype-dependent: Novel insights into the gene-regulatory networks and implications for human hypertension. PLoS One 2017; 12:e0176373. [PMID: 28467442 PMCID: PMC5415177 DOI: 10.1371/journal.pone.0176373] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 04/09/2017] [Indexed: 11/18/2022] Open
Abstract
Single nucleotide polymorphisms (SNPs) in the human angiotensinogen (hAGT) gene may modulate its transcription and affect the regulation of blood pressure via activation of the renin-angiotensin aldosterone system (RAAS). In this regard, we have identified polymorphisms in the 2.5 Kb promoter of the hAGT gene that form two haplotype (Hap) blocks: -6A/G (-1670A/G, -1562C/T, -1561T/C) and -217A/G (-532T/C, -793A/G, -1074T/C & -1178G/A). hAGT gene with Hap -6A/-217A (Hap I) is associated with increased blood pressure whereas, Hap -6G/-217G (Hap II) is associated with normal blood pressure in human subjects. Since RAAS over activity contributes to hypertension in obesity, we have made transgenic mice (TG) containing either Hap I or Hap II of the hAGT gene to understand the role of obesity on its transcriptional regulation. Although, a high-fat diet (60% Kcal from fat, 12 weeks) elevates hAGT and mAGT regardless of haplotype, this effect is significantly (p<0.05) accentuated in Hap I mice, in both adipose and liver tissues. Chromatin Immuno- precipitation (ChIP) assay shows an increased binding of transcription factors including, GR, CEBPβ and STAT3 to the chromatin of the Hap I TG mice after high-fat diet as compared to Hap II TG mice (p<0.05). Differential plasma levels of hAGT in Hap II and I mice, after high-fat diet, further corroborate the variable transcriptional regulation of the hAGT, governed by gene-haplotypes. Taken together, our results show that SNPs in the Hap-I of the hAGT gene promote high-fat diet-induced binding of transcription factors GR, CEBP-β and STAT3, which lead to elevated expression of the hAGT gene in hepatic and adipose tissues.
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Affiliation(s)
- Anita Rana
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
| | - Sudhir Jain
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
| | - Nitin Puri
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
| | - Meenakshi Kaw
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
| | - Natalie Sirianni
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
| | - Deniz Eren
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
| | - Brahma Raju Mopidevi
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
| | - Ashok Kumar
- Department of Physiology and Pharmacology, University Of Toledo Medical Centre, Toledo, Ohio, United States of America
- Department of Pathology, New York Medical College, Valhalla, New York, United States of America
- * E-mail:
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Genetics meets epigenetics: Genetic variants that modulate noncoding RNA in cardiovascular diseases. J Mol Cell Cardiol 2015; 89:27-34. [DOI: 10.1016/j.yjmcc.2015.10.028] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 10/22/2015] [Accepted: 10/23/2015] [Indexed: 12/30/2022]
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Li Q, Sun L, Du J, Ran P, Gao T, Yuan Y, Xiao C. Risk given by AGT polymorphisms in inducing susceptibility to essential hypertension among isolated populations from a remote region of China: A case-control study among the isolated populations. J Renin Angiotensin Aldosterone Syst 2015; 16:1202-17. [PMID: 26391364 DOI: 10.1177/1470320315606315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 07/22/2015] [Indexed: 01/09/2023] Open
Abstract
INTRODUCTION Hypertension is a serious risk factor affecting up to 30% of the world's population with a heritability of more than 30-50%. The aim of this study was to investigate the contribution of the polymorphisms localized in the angiotensinogen (AGT) gene, a main component of the renin-angiotensin-aldosterone system, in inducing the susceptibility to essential hypertension (EH) among isolated populations (Yi and Hani minorities) with low prevalence rate from the remote region of Yunnan in China. METHODS A case-control association study was performed, and all subjects were genotyped for the seven single nucleotide polymorphisms localized in the AGT region by polymerase chain reaction-restriction fragment length polymorphism analysis. RESULTS Three polymorphisms, i.e. rs5046, rs5049, and rs2478544, were significantly associated with EH among the Hani minority. The associations, found in the Yi minority, did not reach a conclusive level of statistical significance. The polymorphisms of rs2478544 and rs5046 caused the transformations of exonic splicing enhancer sites and transcription factor binding sites, respectively, in the bioinformatic analyses. The haplotype-rs5046T, rs5049A, rs11568020G, rs3789679C, rs2478544C was susceptible for EH among the Hani minority. CONCLUSION Our findings suggested that the AGT polymorphisms have played a vital role in determining an individual's susceptibility to EH among the isolated population, which would be helpful for EH management in the remote mountainous region of Yunnan in China.
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Affiliation(s)
- Qian Li
- School of Medicine, Yunnan University, Kunming, China
| | - Lijuan Sun
- School of Medicine, Yunnan University, Kunming, China
| | - Jing Du
- School of Medicine, Yunnan University, Kunming, China
| | - Pengzhan Ran
- School of Medicine, Yunnan University, Kunming, China
| | - Tangxin Gao
- School of Medicine, Yunnan University, Kunming, China
| | - Yuncang Yuan
- School of Medicine, Yunnan University, Kunming, China
| | - Chunjie Xiao
- School of Medicine, Yunnan University, Kunming, China
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Pandey VG, Jain S, Rana A, Puri N, Arudra SKC, Mopidevi B, Kaw M, Nasjletti A, Kumar A. Dexamethasone promotes hypertension by allele-specific regulation of the human angiotensinogen gene. J Biol Chem 2015; 290:5749-58. [PMID: 25568318 DOI: 10.1074/jbc.m114.601922] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The human angiotensinogen (hAGT) gene has polymorphisms in its 2.5-kb promoter that form two haplotype (Hap) blocks: -6A/G (-1670A/G, -1562C/T, and -1561T/C) and -217A/G (-532T/C, -793A/G, -1074T/C, and -1178G/A). Hap -6A/-217A is associated with human hypertension, whereas Hap -6G/-217G reduces cardiovascular risk. Hap -6A/-217A has increased promoter activity with enhanced transcription factor binding, including to the glucocorticoid receptor (GR). Glucocorticoid therapy frequently causes hypertension, the mechanisms for which are incompletely understood. We have engineered double transgenic (TG) mice containing the human renin gene with either Hap of the hAGT gene and examined the physiological significance of glucocorticoid-mediated allele-specific regulation of the hAGT gene. We have also studied the consequential effects on the renin angiotensin system and blood pressure. TG mice with Hap -6A and -6G were treated with and without a low dose of a GR agonist, dexamethasone (2.5 μg/ml), for 72 h. We found greater chromatin-GR binding with increased GR agonist-induced hAGT expression in liver and renal tissues of Hap -6A mice. Additionally, dexamethasone treatment increased circulating hAGT and angiotensin II levels in Hap -6A mice, as compared with -6G mice. Importantly, GR agonist significantly increased blood pressure and redox markers in TG mice with Hap-6A of the hAGT gene. Taken together, our results show, for the first time, that glucocorticoids affect hAGT expression in a haplotype-dependent fashion with SNPs in Hap -6A favoring agonist-induced GR binding. This leads to increased expression of the hAGT, up-regulation of the renin angiotensin system, and increased blood pressure and oxidative stress in Hap -6A mice.
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Affiliation(s)
- Varunkumar G Pandey
- From the Departments of Physiology and Pharmacology and the Department of Pharmacology, New York Medical College, Valhalla, New York, 10595
| | - Sudhir Jain
- From the Departments of Physiology and Pharmacology and
| | - Anita Rana
- From the Departments of Physiology and Pharmacology and
| | - Nitin Puri
- From the Departments of Physiology and Pharmacology and
| | | | | | - Meenakshi Kaw
- From the Departments of Physiology and Pharmacology and
| | | | - Ashok Kumar
- From the Departments of Physiology and Pharmacology and
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Nakamura A. Genotypes of the renin-angiotensin system and glucocorticoid complications. Pediatr Int 2015; 57:72-8. [PMID: 24980618 DOI: 10.1111/ped.12434] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 05/21/2014] [Accepted: 05/26/2014] [Indexed: 01/14/2023]
Abstract
BACKGROUND Angiotensinogen (AGT) and angiotensin-converting enzyme (ACE) are recognized as important regulators of body mass index (BMI) and systemic blood pressure (BP). An association between these single nucleotide polymorphisms (SNP) of AGT and ACE genes and obesity or hypertension has been established. This study examined relationships between the molecular variants of the AGT and ACE genes and bodyweight or BP in children treated with glucocorticoids for nephrotic syndrome. METHODS Twenty Japanese children (male, n = 14; female, n = 6; age, 2-13 years) were genotyped for AGT polymorphisms (M235T and A-6G) and the ACE polymorphisms (insertion/deletion: I/D and rs4341). All of the children studied were treated with daily prednisolone 2 mg/kg for 4 weeks and thereafter alternate-day prednisolone for 8 weeks. BMI, BMI z-scores, blood lipids, renal function and BP in each group were evaluated during the study period. RESULTS BMI and BMI z-scores during the glucocorticoid therapy were significantly higher in the TT genotype of the AGT M235T polymorphisms and the AA genotype of the AGT A-6G polymorphisms compared to other genotypes (P < 0.05). In contrast, the molecular variant of ACE I/D and rs4341 genotypes did not change bodyweight during the glucocorticoid exposure. It was evident, however, that the BP and blood lipids and renal function were not significantly influenced by the AGT and ACE polymorphisms. CONCLUSIONS The TT genotype of the AGT M235T and the AA genotype of the A-6G polymorphisms may predispose children to bodyweight gain when initially treated with glucocorticoids for nephrotic syndrome.
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Affiliation(s)
- Akio Nakamura
- Department of Paediatrics, Teikyo University School of Medicine, Tokyo, Japan; Department of Paediatrics, Social Insurance Omiya General Hospital, Saitama, Japan
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Mopidevi B, Kaw MK, Puri N, Ponnala M, Jain S, Rana A, Keetha NR, Khuder SA, Fiering SN, Kumar A. Variable transcriptional regulation of the human aldosterone synthase gene causes salt-dependent high blood pressure in transgenic mice. ACTA ACUST UNITED AC 2014; 8:30-9. [PMID: 25504670 DOI: 10.1161/circgenetics.114.000694] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Aldosterone, synthesized in the adrenal cortex by the enzyme CYP11B2, induces positive sodium balance and predisposes to hypertension. Various investigators, using genomic DNA analyses, have linked -344T polymorphism in the human CYP11B2 (hCYP11B2) gene to human hypertension. hCYP11B2 gene promoter has 3 single-nucleotide polymorphisms in linkage disequilibrium: T/A at -663, T/C at -470, and C/T at -344. Variants ACT occur together and form the haplotype-I (Hap-I), whereas variants TTC constitute Hap-II. We hypothesize that these single-nucleotide polymorphisms, when present together, will lead to haplotype-dependent differences in the transcriptional regulation of the hCYP11B2 gene and affect blood pressure regulation. METHODS AND RESULTS We evaluated differences in tissue expression in vivo and consequential effects on blood pressure stemming from the 2 haplotypes. Novel transgenic mice with the hCYP11B2 gene, targeted to the mouse HPRT locus, with either Hap-II or Hap-I variant are used in this study. Our results show increased adrenal and renal expression of hCYP11B2 in transgenic mice with Hap-I when compared with mice with Hap-II. Importantly, we observed increased baseline blood pressure in Hap-I transgenic mice, an effect accentuated by a high-salt diet. Pathophysiological effects of elevated aldosterone were corroborated by our results showing upregulation of proinflammatory markers in renal tissues from the transgenic mice with Hap-I. CONCLUSIONS These findings characterize the haplotype-dependent regulation of the hCYP11B2 gene where -344T serves as a reporter polymorphism and show that Hap-I leads to increased expression of hCYP11B2, with permissive effects on blood pressure and inflammatory milieu.
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Affiliation(s)
- Brahmaraju Mopidevi
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Meenakshi K Kaw
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Nitin Puri
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Madhusudan Ponnala
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Sudhir Jain
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Anita Rana
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Narsimha R Keetha
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Sadik A Khuder
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Steven N Fiering
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.)
| | - Ashok Kumar
- From the Department of Physiology and Pharmacology (B.M., M.K.K., N.P., M.P., S.J., A.R., N.R.K., A.K.) and Department of Medicine (S.A.K.), College of Medicine, University of Toledo, OH; and Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH (S.N.F.).
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Jain S, Prater A, Pandey V, Rana A, Puri N, Kumar A. A haplotype of angiotensin receptor type 1 associated with human hypertension increases blood pressure in transgenic mice. J Biol Chem 2013; 288:37048-56. [PMID: 24202179 DOI: 10.1074/jbc.m113.520023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The renin-angiotensin system plays an important role in the regulation of blood pressure via angiotensin II and the angiotensin II receptor type 1 (AT1R). Human AT1R gene promoter has four SNPs: T/A at -777, T/G at -680, A/C at -214, and A/G at -119, that are in linkage disequilibrium. Variants -777T, -680T, -214A, and -119A almost always occur together (named haplotype I), and variants -777A, -680G, -214C, and -119G almost always occur together (named haplotype II) in Caucasian subjects. Genomic DNA analyses, from 388 normotensive and 374 hypertensive subjects, link haplotype I of the human AT1R (hAT1R) gene with hypertension in Caucasians (p = 0.004, χ(2) = 8.46). Our results show increased basal promoter activity of the hAT1R gene in cells (H295R and A7r5) transfected with reporter construct containing haplotype I. We also show increased binding of the transcription factor, USF2, to oligonucleotide containing nucleoside -214A as opposed to -214C. Recombineering of a 166-kb bacterial artificial chromosome containing 68 kb of the 5'-flanking region, 45 kb of the coding sequence, and 53 kb of the 3'-flanking region of the hAT1R gene was employed to generate transgenic mice with either haplotype. We show that (a) hAT1R mRNA level is increased in the kidney and heart of transgenic mice containing haplotype I as compared with haplotype II; (b) USF2 binds more strongly to the chromatin obtained from the kidney of transgenic mice containing haplotype I as compared with haplotype II; and (c) blood pressure and oxidative stress are increased in transgenic mice containing haplotype I as compared with haplotype II.
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Affiliation(s)
- Sudhir Jain
- From the Department of Physiology and Pharmacology, University of Toledo Health Science Campus, Toledo, Ohio 43614
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Mopidevi B, Ponnala M, Kumar A. Human angiotensinogen +11525 C/A polymorphism modulates its gene expression through microRNA binding. Physiol Genomics 2013; 45:901-6. [PMID: 23943853 DOI: 10.1152/physiolgenomics.00056.2013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Hypertension is a serious risk factor for cardiovascular disease. Like other complex disease, hypertension is caused by a combination of genetic and environmental factors. The renin-angiotensin system plays an important role in the regulation of blood pressure. Angiotensinogen (AGT) gene is associated with essential hypertension in Caucasians, Japanese, and Asian-Indian subjects. AGT gene may also be associated with cardiac hypertrophy, coronary atherosclerosis, and microangiopathy related cerebral damage. Human AGT gene has a C/A polymorphism at nucleoside 11525 (rs7079) that is located in the 3'-untranslated region (3'-UTR) and is modestly associated with increased blood pressure. We show here that miR-31 and miR-584 bind strongly to the hAGT 3'-UTR containing 11525C allele compared with 11525A allele. We also show that transfection of miR-31 and miR-584 downregulates the hAGT mRNA and protein levels in human liver cells. These studies may provide new therapeutic approach to reduce hypertension.
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Affiliation(s)
- Brahmaraju Mopidevi
- Department of Physiology and Pharmacology, University of Toledo Health Science Campus, Toledo, Ohio
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Li YY. Lack of association of A-6G polymorphism of AGT gene with essential hypertension in the Chinese population. J Cardiovasc Med (Hagerstown) 2012; 13:505-10. [PMID: 22710764 DOI: 10.2459/jcm.0b013e328355a726] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND The angiotensinogen (AGT) A-6G gene polymorphism has been indicated to be related to the susceptibility of essential hypertension. However, the results are still unclear. OBJECTIVE AND METHODS To survey the relationship between AGT A-6G gene polymorphism and essential hypertension, 18 separate studies with 9306 patients were analyzed through meta-analysis. The random-effect model was used to calculate the pooled odds ratio (OR) and its corresponding 95% confidence interval (CI). RESULTS In this AGT A-6G gene polymorphism and essential hypertension meta-analysis of the Chinese population, the distribution of the G-allele frequency was 0.23 for the essential hypertension group and 0.21 for the control group. The association between the AGT A-6G gene polymorphism and essential hypertension in the entire sample population was not significant. The pooled OR for the frequency of the G allele was 1.10 (95% CI 0.96 to 1.27, Pheterogeneity < 0.00001, P = 0.17). In the stratified analysis by ethnicity, a significant association in Li and Mongolian ethnicities (P ≤ 0.05) was achieved. However, no significant association was found in other ethnicities such as Han, Tibetan, Kazakh, Bai and Yi (P > 0.05). CONCLUSIONS The current meta-analysis suggested that AGT A-6G gene polymorphism might not be related to the increased risk of essential hypertension in the entire Chinese population. However, the G-allele of AGT A-6G might predispose to essential hypertension in the Li and Mongolian ethnicities.
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Affiliation(s)
- Yan-yan Li
- Department of Geriatrics, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
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A-6G and A-20C polymorphisms in the angiotensinogen promoter and hypertension risk in Chinese: a meta-analysis. PLoS One 2011; 6:e29489. [PMID: 22216295 PMCID: PMC3247271 DOI: 10.1371/journal.pone.0029489] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 11/29/2011] [Indexed: 11/19/2022] Open
Abstract
Background Numerous studies in Chinese populations have evaluated the association between the A-6G and A-20C polymorphisms in the promoter region of angiotensinogen gene and hypertension. However, the results remain conflicting. We carried out a meta-analysis for these associations. Methods and Results Case–control studies in Chinese and English publications were identified by searching the MEDLINE, EMBASE, CNKI, Wanfang, CBM, and VIP databases. The random-effects model was applied for dichotomous outcomes to combine the results of the individual studies. We finally selected 24 studies containing 5932 hypertensive patients and 5231 normotensive controls. Overall, we found significant association between the A-6G polymorphism and the decreased risk of hypertension in the dominant genetic model (AA+AG vs. GG: P = 0.001, OR = 0.71, 95%CI 0.57–0.87, Pheterogeneity = 0.96). The A-20C polymorphism was significantly associated with the increased risk for hypertension in the allele comparison (C vs. A: P = 0.03, OR = 1.14, 95%CI 1.02–1.27, Pheterogeneity = 0.92) and recessive genetic model (CC vs. CA+AA: P = 0.005, OR = 1.71, 95%CI 1.18–2.48, Pheterogeneity = 0.99). In the subgroup analysis by ethnicity, significant association was also found among Han Chinese for both A-6G and A-20C polymorphisms. A borderline significantly decreased risk of hypertension between A-6G and Chinese Mongolian was seen in the allele comparison (A vs. G: P = 0.05, OR = 0.79, 95%CI 0.62–1.00, Pheterogeneity = 0.84). Conclusion Our meta-analysis indicated significant association between angiotensinogen promoter polymorphisms and hypertension in the Chinese populations, especially in Han Chinese.
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