Hypertension and renin-angiotensin system blockers are not associated with expression of angiotensin-converting enzyme 2 (ACE2) in the kidney
- Authors: Jiang, Xiao , Eales, James , Scannali, David , Prestes, Priscilla , Charchar, Fadi
- Date: 2020
- Type: Text , Journal article
- Relation: European Heart Journal Vol. 41, no. 48 (2020), p. 4580-4588
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- Description: Aims Angiotensin-converting enzyme 2 (ACE2) is the cellular entry point for severe acute respiratory syndrome coronavirus (SARS-CoV-2) - the cause of coronavirus disease 2019 (COVID-19). However, the effect of renin-angiotensin system (RAS)-inhibition on ACE2 expression in human tissues of key relevance to blood pressure regulation and COVID-19 infection has not previously been reported. Methods and results We examined how hypertension, its major metabolic co-phenotypes, and antihypertensive medications relate to ACE2 renal expression using information from up to 436 patients whose kidney transcriptomes were characterized by RNA-sequencing. We further validated some of the key observations in other human tissues and/or a controlled experimental model. Our data reveal increasing expression of ACE2 with age in both human lungs and the kidney. We show no association between renal expression of ACE2 and either hypertension or common types of RAS inhibiting drugs. We demonstrate that renal abundance of ACE2 is positively associated with a biochemical index of kidney function and show a strong enrichment for genes responsible for kidney health and disease in ACE2 coexpression analysis. Conclusion Our results indicate that neither hypertension nor antihypertensive treatment is likely to alter the expression of the key entry receptor for SARS-CoV-2 in the human kidney. Our data further suggest that in the absence of SARS-CoV-2 infection, kidney ACE2 is most likely nephro-protective but the age-related increase in its expression within lungs and kidneys may be relevant to the risk of SARS-CoV-2 infection. © The Author(s) 2020. *Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliates “James Eales", "Priscilla Prestes" and "Fadi Charchar” are provided in this record**
May measurement month 2019 the global blood pressure screening campaign of the International Society of Hypertension
- Authors: Beaney, Thomas , Schutte, Aletta , Stergiou, George , Borghi, Claudio , Burger, Dylan , Charchar, Fadi , Cro, Suzie , Diaz, Alejandro , Damasceno, Albertino , Espeche, Walter , Jose, Arun , Khan, Nadia , Kokubo, Yoshihiro , Maheshwari, Anuj , Marin, Marcos , More, Arun , Neupane, Dinesh , Nilsson, Peter , Patil, Mansi , Prabhakaran, Dorairaj , Ramirez, Agustin , Rodriguez, Pablo , Schlaich, Markus , Steckelings, Ulrike , Tomaszewski, Maciej , Unger, Thomas , Wainford, Richard , Wang, Jiguang , Williams, Bryan , Poulter, Neil , M. M. M. Investigators
- Date: 2020
- Type: Text , Journal article
- Relation: Hypertension Vol. 76, no. 2 (Aug 2020), p. 333-341
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- Description: Elevated blood pressure remains the single biggest risk factor contributing to the global burden of disease and mortality. May Measurement Month is an annual global screening campaign aiming to improve awareness of blood pressure at the individual and population level. Adults (>= 18 years) recruited through opportunistic sampling were screened at sites in 92 countries during May 2019. Ideally, 3 blood pressure readings were measured for each participant, and data on lifestyle factors and comorbidities were collected. Hypertension was defined as a systolic blood pressure >= 140 mm Hg, or a diastolic blood pressure >= 90 mm Hg (mean of the second and third readings) or taking antihypertensive medication. When necessary, multiple imputation was used to estimate participants' mean blood pressure. Mixed-effects models were used to evaluate associations between blood pressure and participant characteristics. Of 1 508 130 screenees 482 273 (32.0%) had never had a blood pressure measurement before and 513 337 (34.0%) had hypertension, of whom 58.7% were aware, and 54.7% were on antihypertensive medication. Of those on medication, 57.8% were controlled to <140/90 mm Hg, and 28.9% to <130/80 mm Hg. Of all those with hypertension, 31.7% were controlled to <140/90 mm Hg, and 350 825 (23.3%) participants had untreated or inadequately treated hypertension. Of those taking antihypertensive medication, half were taking only a single drug, and 25% reported using aspirin inappropriately. This survey is the largest ever synchronized and standardized contemporary compilation of global blood pressure data. This campaign is needed as a temporary substitute for systematic blood pressure screening in many countries worldwide.
Neural suppression of miRNA-181a in the kidney elevates renin expression and exacerbates hypertension in Schlager mice
- Authors: Jackson, Kristy , Gueguen, Cindy , Lim, Kyungjoon , Eikelis, Nina , Stevenson, Emily , Charchar, Fadi , Lambert, Gavin , Burke, Sandra , Paterson, Madeleine , Marques, Francine , Head, Geoffrey
- Date: 2020
- Type: Text , Journal article
- Relation: Hypertension Research Vol. 43, no. 11 (2020), p. 1152-1164
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- Description: BPH/2J mice are a genetic model of hypertension with overactivity of the sympathetic nervous system (SNS) and renin–angiotensin system (RAS). BPH/2J display higher renal renin mRNA and low levels of its negative regulator microRNA-181a (miR-181a). We hypothesise that high renal SNS activity may reduce miR-181a expression, which contributes to elevated RAS activity and hypertension in BPH/2J. Our aim was to determine whether in vivo administration of a renal-specific miR-181a mimic or whether renal denervation could increase renal miR-181a abundance to reduce renal renin mRNA, RAS activity and hypertension in BPH/2J mice. Blood pressure (BP) in BPH/2J and normotensive BPN/3J mice was measured via radiotelemetry probes. Mice were administered miR-181a mimic or a negative control (1–25 nmol, i.v., n = 6–10) with BP measured for 48 h after each dose or they underwent renal denervation or sham surgery (n = 7–9). Injection of 5–25 nmol miR-181a mimic reduced BP in BPH/2J mice after 36–48 h (−5.3 ± 1.8, −6.1 ± 1.9 mmHg, respectively, P < 0.016). Treatment resulted in lower renal renin and inflammatory marker (TLR4) mRNA levels in BPH/2J. The mimic abolished the hypotensive effect of blocking the RAS with enalaprilat (P < 0.01). No differences between mimic or vehicle were observed in BPN/3J mice except for a higher level of renal angiotensinogen in the mimic-treated mice. Renal miR-181a levels that were lower in sham BPH/2J mice were greater following renal denervation and were thus similar to those of BPN/3J. Our findings suggest that the reduced renal miR-181a may partially contribute to the elevated BP in BPH/2J mice, through an interaction between the renal sympathetic nerves and miR-181a regulation of the RAS. © 2020, The Japanese Society of Hypertension.
- Description: This work was supported by a grant from the National Health & Medical Research Council of Australia (NHMRC, Project grant 1065714) and in part by the Victorian Government’s OIS Program. Investigators were supported by NHMRC/National Heart Foundation (NHF) Postdoctoral Fellowships (NHMRC APP1091688 to KLJ, NHMRC APP1052659 and NHF PF12M6785 and 101185 to FZM) and NHMRC Research Fellowships (APP1042492 to GWL and APP1002186 to GAH).
The prevalence of cardiovascular risk factors and cardiovascular disease among primary care patients in Poland : results from the LIPIDOGRAM2015 study
- Authors: Jóźwiak, Jacek , Studziński, Krzysztof , Tomasik, Tomasz , Windak, Adam , Charchar, Fadi
- Date: 2020
- Type: Text , Journal article
- Relation: Atherosclerosis Supplements Vol. 42, no. (2020), p. e15-e24
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- Description: Background and aim: To estimate the prevalence of cardiovascular (CV) disease and CV risk factors among Polish patients. Methods: A nationwide cross-sectional study, LIPIDOGRAM2015, was carried out in Poland in the 4th quarter of 2015 and 1st and 2nd quarters of 2016; 438 primary care physicians enrolled 13,724 adult patients that sought medical care in primary health care practices. Results: Nearly 19% of men and approximately 12% of women had cardiovascular disease (CVD). Over 60% of the recruited patients had hypertension (HTN), >80% had dyslipidaemia and <15% of patients were diagnosed with diabetes (DM). All of these disorders were more frequent in men. In 80% of patients the waist circumference exceed norm for the European population. Less than half of the patients were current smokers or had smoked in the past. Patients with CVD had significantly higher blood pressure and glucose levels but lower low density lipoprotein-cholesterol level. Conclusions: The prevalence of CVD and CV risk factors among patients in Poland is high. CVD is more common in men than in women. The most common CV risk factors are excess waist circumference, dyslipidaemia and HTN. Family physicians should conduct activities to prevent, diagnose early and treat CVD in the primary health care population. © 2021 Elsevier B.V. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Fadi Charchar” is provided in this record**
May measurement month 2018 : A pragmatic global screening campaign to raise awareness of blood pressure by the international society of hypertension
- Authors: Beaney, Thomas , Burrell, Louise , Castillo, Rafael , Charchar, Fadi , Cro, Suzie , Damasceno, Albertino , Kruger, Ruan , Nilsson, Peter , Prabhakaran, Dorairaj , Ramirez, Agustin , Schlaich, Markus , Schutte, Aletta , Tomaszewski, Maciej , Touyz, Rhian , Wang, Ji-Guang , Weber, Michael , Poulter, Neil
- Date: 2019
- Type: Text , Journal article , Review
- Relation: European Heart Journal Vol. 40, no. 25 (2019), p. 2006-2017
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- Description: Aims: Raised blood pressure (BP) is the biggest contributor to mortality and disease burden worldwide and fewer than half of those with hypertension are aware of it. May Measurement Month (MMM) is a global campaign set up in 2017, to raise awareness of high BP and as a pragmatic solution to a lack of formal screening worldwide. The 2018 campaign was expanded, aiming to include more participants and countries. Methods and results: Eighty-nine countries participated in MMM 2018. Volunteers (≥18 years) were recruited through opportunistic sampling at a variety of screening sites. Each participant had three BP measurements and completed a questionnaire on demographic, lifestyle, and environmental factors. Hypertension was defined as a systolic BP ≥140mmHg or diastolic BP ≥90 mmHg, or taking antihypertensive medication. In total, 74.9% of screenees provided three BP readings. Multiple imputation using chained equations was used to impute missing readings. 1 504 963 individuals (mean age 45.3 years; 52.4% female) were screened. After multiple imputation, 502 079 (33.4%) individuals had hypertension, of whom 59.5% were aware of their diagnosis and 55.3% were taking antihypertensive medication. Of those on medication, 60.0% were controlled and of all hypertensives, 33.2% were controlled. We detected 224 285 individuals with untreated hypertension and 111 214 individuals with inadequately treated (systolic BP ≥ 140mmHg or diastolic BP ≥ 90 mmHg) hypertension. Conclusion: May Measurement Month expanded significantly compared with 2017, including more participants in more countries. The campaign identified over 335 000 adults with untreated or inadequately treated hypertension. In the absence of systematic screening programmes, MMM was effective at raising awareness at least among these individuals at risk.
Renal nerves contribute to hypertension in Schlager BPH/2J mice
- Authors: Gueguen, Cindy , Jackson, Kristy , Marques, Francine , Eikelis, Nina , Phillips, Sarah , Stevenson, Emily , Charchar, Fadi , Lambert, Gavin , Davern, Pamela , Head, Geoffrey
- Date: 2019
- Type: Text , Journal article
- Relation: Hypertension Research Vol. 42, no. 3 (2019), p. 306-318
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- Description: Schlager mice (BPH/2J) are hypertensive due to a greater contribution of the sympathetic nervous system (SNS) and renin-angiotensin system (RAS). The kidneys of BPH/2J are hyper-innervated suggesting renal nerves may contribute to the hypertension. We therefore determined the effect of bilateral renal denervation (RD) on hypertension in BPH/2J. Mean arterial pressure (MAP) was measured by radiotelemetry before and for 3 weeks after RD in BPH/2J and BPN/3J. The effects of pentolinium and enalaprilat were examined to determine the contribution of the SNS and RAS, respectively. After 3 weeks, MAP was −10.9 ± 2.1 mmHg lower in RD BPH/2J compared to baseline and −2.1 ± 2.2 mmHg in sham BPH/2J (P < 0.001, n = 8–10). RD had no effect in BPN/3J (P > 0.1). The depressor response to pentolinium was greater in BPH/2J than BPN/3J, but in both cases the response in RD mice was similar to sham. Enalaprilat decreased MAP more in RD BPH/2J compared to sham (−12 vs −3 mmHg, P < 0.001) but had no effect in BPN/3J. RD reduced renal noradrenaline in both strains but more so in BPH/2J. RD reduced renin mRNA and protein, but not plasma renin in BPH/2J to levels comparable with BPN/3J mice. We conclude that renal nerves contribute to hypertension in BPH mice as RD induced a sustained fall in MAP, which was associated with a reduction of intrarenal renin expression. The lack of inhibition of the depressor effects of pentolinium and enalaprilat by RD suggests that vasoconstrictor effects of the SNS or RAS are not involved.
The association between serum uric acid and blood pressure in different age groups in a healthy Chinese cohort
- Authors: Cheng, Wenjuan , Wen, Shiling , Wang, Yutang , Qian, Zhiping , Tan, Yuyao , Li, Hongying , Hou, Yueli , Hu, Haiyang , Golledge, Jonathan , Yang, Guang
- Date: 2017
- Type: Text , Journal article
- Relation: Medicine (United States) Vol. 96, no. 50 (2017), p.1-6
- Relation: http://purl.org/au-research/grants/nhmrc/1062671
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- Description: High serum uric acid (sUA) has been reported to be a risk factor for hypertension however, whether this is the case for all age groups is not clear. We examined the association between sUA concentrations and systolic and diastolic blood pressure (SBP and DBP) in different age groups in a cohort of healthy Chinese participants. A total of 1082 healthy participants aged from 41 to 70 years were included. sUA concentration was measured by the uricase-peroxidase method. SBP and DBP were assessed using mercury sphygmomanometry. Hypertension was defined as SBP ≥140 mm Hg or DBP ≥90 mm Hg. Hyperuricemia (HUA) was defined as sUA concentration of >7 mg/dL in men and >6 mg/dL in women. The association between sUA concentration and SBP and DBP was examined using Pearson's correlation test, multivariate linear regression, and logistic regression analysis. The prevalence of hypertension and HUA increased with age (P < .001). Hypertension was more common in participants that had HUA than in those that did not (38.95% vs 30.16%, P = .02). Higher sUA was significantly associated with higher SBP and DBP in the 41- to 50-year-old participants (SBP, β = 0.35, P < .001; DBP, β = .29, P < .001; after adjustment for age, sex, total cholesterol, estimated glomerular filtration rate, and fasting plasma glucose). HUA was also a risk factor for hypertension in this age group (odds ratio 1.425, 95% confidence interval, 1.217-1.668, P < .001). There was no association between sUA concentration and SBP and DBP in the other age groups. In this population of healthy Chinese participants, sUA concentration was positively associated with hypertension only in the 41- to 50-year-old group. Lowering uric acid in this age group may help to reduce the incidence of hypertension.
A multi-omics glimpse into the biology of arterial stiffness
- Authors: Eales, James , Romaine, Simon , Charchar, Fadi , Tomaszewski, Maciej
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of Hypertension Vol. 34, no. 1 (2015), p. 32-35
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- Description: It has long been recognized that the structure of arteries throughout the vascular tree is not uniform. Notably, the media of large proximal (central) vessels contains relatively much greater amounts of elastin and elastic lamellae than smaller, more distal (peripheral) arteries; the converse is true of vascular smooth muscle cells. Under physiological conditions, the greater elasticity of central arteries compared with more muscular peripheral arteries allows conversion of the pulsatile nature of ventricular ejection into a relatively steady flow of blood at the distal end of the arterial system, conferring protection from pulsatile energy [1,2]. Furthermore, these differences in impedance can generate partial wave reflections, which arrive in the aorta during diastole, boosting diastolic blood pressure and augmenting coronary perfusion pressure [3].
Renal Mechanisms of Association between Fibroblast Growth Factor 1 and Blood Pressure
- Authors: Tomaszewski, Maciej , Eales, James , Denniff, Matthew , Myers, Stephen , Chew, Guatsiew , Nelson, Christopher , Christofidou, Paraskevi , Desai, Aishwarya , Büsst, Cara , Wojnar, Lukasz , Musialik, Katarzyna , Jozwiak, Jacek , Debiec, Radoslaw , Dominiczak, Anna , Navis, Gerjan , van Gilst, Wiek , van der Harst, Pim , Samani, Nilesh , Harrap, Stephen , Bogdanski, Pawel , Zukowska-Szczechowska, Ewa , Charchar, Fadi
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of the American Society of Nephrology Vol. 26, no. 12 (2015), p. 3151-3160
- Relation: http://purl.org/au-research/grants/nhmrc/1009490
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- Description: The fibroblast growth factor 1 (FGF1) gene is expressed primarily in the kidney and may contribute to hypertension. However, the biologic mechanisms underlying the association between FGF1 and BP regulation remain unknown. We report that the major allele of FGF1 single nucleotide polymorphism rs152524 was associated in a dose-dependent manner with systolic BP (P=9.65 x10(-5)) and diastolic BP (P=7.61 x10(-3)) in a meta-analysis of 14,364 individuals and with renal expression of FGF1 mRNA in 126 human kidneys (P=9.0x10(-3)). Next-generation RNA sequencing revealed that upregulated renal expression of FGF1 or of each of the three FGF1 mRNA isoforms individually was associated with higher BP. FGF1-stratified coexpression analysis in two separate collections of human kidneys identified 126 FGF1 partner mRNAs, of which 71 and 63 showed at least nominal association with systolic and diastolic BP, respectively. Of those mRNAs, seven mRNAs in five genes (MME, PTPRO, REN, SLC12A3, and WNK1) had strong prior annotation to BP or hypertension. MME, which encodes an enzyme that degrades circulating natriuretic peptides, showed the strongest differential coexpression with FGF1 between hypertensive and normotensive kidneys. Furthermore, higher level of renal FGF1 expression was associated with lower circulating levels of atrial and brain natriuretic peptides. These findings indicate that FGF1 expression in the kidney is at least under partial genetic control and that renal expression of several FGF1 partner genes involved in the natriuretic peptide catabolism pathway, reninangiotensin cascade, and sodium handling network may explain the association between FGF1 and BP.
The emerging role of non-coding RNA in essential hypertension and blood pressure regulation
- Authors: Marques, Francine , Booth, Scott , Charchar, Fadi
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of Human Hypertension Vol. 29, no. 8 (2015), p. 459-467
- Relation: http://purl.org/au-research/grants/nhmrc/1009490
- Full Text: false
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- Description: Unravelling the complete genetic predisposition to high blood pressure (BP) has proven to be challenging. This puzzle and the fact that coding regions of the genome account for less than 2% of the entire human DNA support the hypothesis that genetic mechanism besides coding genes are likely to contribute to BP regulation. Non-coding RNAs (ncRNAs) are emerging as key players of transcription regulation in both health and disease states. They control basic functions in virtually all cell types relevant to the cardiovascular system and, thus, a direct involvement with BP regulation is highly probable. Here, we review the literature about ncRNAs associated with human BP and essential hypertension, highlighting investigations, methodology and difficulties arising in the field. The most investigated ncRNAs so far are microRNAs (miRNAs), small ncRNAs that modulate gene expression by posttranscriptional mechanisms. We discuss studies that have examined miRNAs associated with BP in biological fluids, such as blood and urine, and tissues, such as vascular smooth muscle cells and the kidney. Furthermore, we review the interaction between miRNA binding sites and single nucleotide polymorphisms in genes associated with BP. In conclusion, there is a clear need for more human and functional studies to help elucidate the multifaceted roles of ncRNAs, in particular mid- and long ncRNAs in BP regulation. © 2015 Macmillan Publishers Limited All rights reserved.
Mouse models of intracranial aneurysm
- Authors: Wang, Yutang , Emeto, Theophilus , Lee, James , Marshman, Laurence , Moran, Corey , Seto, Sai-wang , Golledge, Jonathan
- Date: 2014
- Type: Text , Journal article
- Relation: Brain Pathology Vol. 25, no. (2014), p. 237-247
- Relation: http://purl.org/au-research/grants/nhmrc/1062671
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- Description: Subarachnoid hemorrhage secondary to rupture of an intracranial aneurysm is a highly lethal medical condition. Current management strategies for unruptured intracranial aneurysms involve radiological surveillance and neurosurgical or endovascular interventions. There is no pharmacological treatment available to decrease the risk of aneurysm rupture and subsequent subarachnoid hemorrhage. There is growing interest in the pathogenesis of intracranial aneurysm focused on the development of drug therapies to decrease the incidence of aneurysm rupture. The study of rodent models of intracranial aneurysms has the potential to improve our understanding of intracranial aneurysm development and progression. This review summarizes current mouse models of intact and ruptured intracranial aneurysms and discusses the relevance of these models to human intracranial aneurysms. The article also reviews the importance of these models in investigating the molecular mechanisms involved in the disease. Finally, potential pharmaceutical targets for intracranial aneurysm suggested by previous studies are discussed. Examples of potential drug targets include matrix metalloproteinases, stromal cell-derived factor-1, tumor necrosis factor-α, the renin-angiotensin system and the β-estrogen receptor. An agreed clear, precise and reproducible definition of what constitutes an aneurysm in the models would assist in their use to better understand the pathology of intracranial aneurysm and applying findings to patients
- Description: Subarachnoid hemorrhage secondary to rupture of an intracranial aneurysm is a highly lethal medical condition. Current management strategies for unruptured intracranial aneurysms involve radiological surveillance and neurosurgical or endovascular interventions. There is no pharmacological treatment available to decrease the risk of aneurysm rupture and subsequent subarachnoid hemorrhage. There is growing interest in the pathogenesis of intracranial aneurysm focused on the development of drug therapies to decrease the incidence of aneurysm rupture. The study of rodent models of intracranial aneurysms has the potential to improve our understanding of intracranial aneurysm development and progression. This review summarizes current mouse models of intact and ruptured intracranial aneurysms and discusses the relevance of these models to human intracranial aneurysms. The article also reviews the importance of these models in investigating the molecular mechanisms involved in the disease. Finally, potential pharmaceutical targets for intracranial aneurysm suggested by previous studies are discussed. Examples of potential drug targets include matrix metalloproteinases, stromal cell-derived factor-1, tumor necrosis factor-
Report of the 3rd annual International Society of Hypertension New Investigator Symposium.
- Authors: Burger, Dylan , Veerabhadrappa, Praveen , Charchar, Fadi , Schutte, Aletta , Tomaszewski, Maciej
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of hypertension Vol. 32, no. 4 (2014), p. 448-449
- Full Text: false
- Reviewed:
A novel interaction between sympathetic overactivity and aberrant regulation of renin by miR-181a in BPH/2J genetically hypertensive mice
- Authors: Jackson, Kristy , Marques, Francine , Watson, Anna , Palma-Rigo, Keisia , Nguyen-Huu, Thu-Phuc , Morris, Brian , Charchar, Fadi , Davern, Pamela , Head, Geoffrey
- Date: 2013
- Type: Text , Journal article
- Relation: Hypertension Vol. 62 , no. 4 (2013), p. 775-781
- Full Text: false
- Reviewed:
- Description: Genetically hypertensive mice (BPH/2J) are hypertensive because of an exaggerated contribution of the sympathetic nervous system to blood pressure. We hypothesize that an additional contribution to elevated blood pressure is via sympathetically mediated activation of the intrarenal renin-angiotensin system. Our aim was to determine the contribution of the renin-angiotensin system and sympathetic nervous system to hypertension in BPH/2J mice. BPH/2J and normotensive BPN/3J mice were preimplanted with radiotelemetry devices to measure blood pressure. Depressor responses to ganglion blocker pentolinium (5 mg/kg i.p.) in mice pretreated with the angiotensin-converting enzyme inhibitor enalaprilat (1.5 mg/kg i.p.) revealed a 2-fold greater sympathetic contribution to blood pressure in BPH/2J mice during the active and inactive period. However, the depressor response to enalaprilat was 4-fold greater in BPH/2J compared with BPN/3J mice, but only during the active period (P=0.01). This was associated with 1.6-fold higher renal renin messenger RNA (mRNA; P=0.02) and 0.8-fold lower abundance of micro-RNA-181a (P=0.03), identified previously as regulating human renin mRNA. Renin mRNA levels correlated positively with depressor responses to pentolinium (r=0.99; P=0.001), and BPH/2J mice had greater renal sympathetic innervation density as identified by tyrosine hydroxylase staining of cortical tubules. Although there is a major sympathetic contribution to hypertension in BPH/2J mice, the renin-angiotensin system also contributes, doing so to a greater extent during the active period and less during the inactive period. This is the opposite of the normal renin-angiotensin system circadian pattern. We suggest that renal hyperinnervation and enhanced sympathetically induced renin synthesis mediated by lower micro-RNA-181a contributes to hypertension in BPH/2J mice.
Pathway analysis shows association between FGFBP1 and hypertension
- Authors: Tomaszewski, Maciej , Charchar, Fadi , Nelson, Christopher , Barnes, Timothy , Denniff, Matthew , Kaiser, Michael , Debiec, Radoslaw , Christofidou, Paraskevi , Rafelt, Suzanne , Van Harst, Pim Der , Wang, William , Maric, Christine , Zukowska-Szczechowska, Ewa , Samani, Nilesh
- Date: 2011
- Type: Text , Journal article
- Relation: Journal of the American Society of Nephrology Vol. 22, no. 5 (2011), p. 947-955
- Full Text: false
- Reviewed:
- Description: Variants in the gene encoding fibroblast growth factor 1 (FGF1) co-segregate with familial susceptibility to hypertension, and glomerular upregulation of FGF1 associates with hypertension. To investigate whether variants in other members of the FGF signaling pathway may also associate with hypertension, we genotyped 629 subjects from 207 Polish families with hypertension for 79 single nucleotide polymorphisms in eight genes of this network. Family-based analysis showed that parents transmitted the major allele of the rs16892645 polymorphism in the gene encoding FGF binding protein 1 (FGFBP1) to hypertensive offspring more frequently than expected by chance (P = 0.005). An independent cohort of 807 unrelated Polish subjects validated this association. Furthermore, compared with normotensive subjects, hypertensive subjects had approximately 1.5- and 1.4-fold higher expression of renal FGFBP1 mRNA and protein (P = 0.04 and P = 0.001), respectively. By immunohistochemistry, hypertensionrelated upregulation of FGFBP1 was most apparent in the glomerulus and juxtaglomerular space. Taken together, these data suggest that FGFBP1 associates with hypertension and that systematic analysis of signaling pathways can identify previously undescribed genetic associations. Copyright © 2011 by the American Society of Nephrology.
Whole genome survey of copy number variation in the spontaneously hypertensive rat relationship to quantitative trait loci, gene expression, and blood pressure
- Authors: Charchar, Fadi , Kaiser, Michael , Bingham, Andrew , Fotinatos, Nina , Ahmady, Fahima , Tomaszewski, Maciej , Samani, Nilesh
- Date: 2010
- Type: Text , Journal article
- Relation: Hypertension Vol. 55, no. 5 (2010), p. 1231-1238
- Full Text: false
- Reviewed:
- Description: Copy number variation has emerged recently as an important genetic mechanism leading to phenotypic heterogeneity. The aim of our study was to determine whether copy number variants (CNVs) exist between the spontaneously hypertensive rat (SHR) and its control strain, the Wistar-Kyoto rat, whether these map to quantitative trait loci in the rat and whether CNVs associate with gene expression or blood pressure differences between the 2 strains. We performed a comparative genomic hybridization assay between SHR and Wistar-Kyoto strains using a whole-genome array. In total, 16 CNVs were identified and validated (6 because of a relative loss of copy number in the SHR and 10 because of a relative gain). CNVs were present on rat autosomes 1, 3, 4, 6, 7, 10, 14, and 17 and varied in size from 10.0 kb to 1.6 Mb. Most of these CNVs mapped to chromosomal regions within previously identified quantitative trait loci, including those for blood pressure in the SHR. Transcriptomic experiment! s confirmed differences in the renal expression of several genes (including Ms4a6a, Ndr3, Egln1, Cd36, Sema3a, Ugt2b, and Idi21) located in some of the CNVs between STIR and Wistar-Kyoto rats. In F-2 animals derived from an SHRXWistar-Kyoto cross, we also found a significant increase in blood pressure associated with an increase in copy number in the Egln1 gene. Our findings suggest that, CNVs may play a role in the susceptibility to hypertension and related trails in the SHR. (Hypertension. 2010;55:1231-1238.)
Whole genome survey of copy number variation in the spontaneously hypertensive rat
- Authors: Charchar, Fadi , Samani, Nilesh
- Date: 2008
- Type: Text , Journal article
- Relation: Hypertension Vol. 52, no. 4 (Oct 2008), p. E100-E100
- Full Text: false
- Reviewed:
- Description: C1