Showing items 1 - 20 of 108

A modified MTS proliferation assay for suspended cells to avoid the interference by hydralazine and β-Mercaptoethanol

- Wang, Yutang, Nguyen, Dinh, Anesi, Jack, Kelly, Jason, Ahmady, Fahima, Charchar, Fadi

  • Authors: Wang, Yutang , Nguyen, Dinh , Anesi, Jack , Kelly, Jason , Ahmady, Fahima , Charchar, Fadi
  • Date: 2021
  • Type: Text , Journal article
  • Relation: Assay and Drug Development Technologies Vol. 19, no. 3 (2021), p. 184-190. https://purl.org/au-research/grants/nhmrc/1062671
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  • Description: The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay is one of the most commonly used tests of cell proliferation. Hydralazine has been reported to interfere with the performance of the MTS assay when used on adherent cells. This study aimed to investigate whether hydralazine interferes with the performance of the MTS assay on suspended cells. THP-1 (a monocytic leukemia cell line) cells were cultured in the presence or absence of hydralazine (0, 10, 50, 100, and 500 μM) for 2 or 24 h. Cell numbers were analyzed using the MTS, trypan blue exclusion, or microscopic assays. A modified version of the standard MTS assay was established by centrifuging the cells and replacing the test medium with fresh culture medium immediately before the addition of the MTS reagent. Culture of THP-1 cells with hydralazine at concentrations of 50, 100, and 500 μM for 2 h increased absorbance (p < 0.001) in the standard MTS assay, whereas both the trypan blue exclusion assay and microscopy suggested no change in cell numbers. Culture of THP-1 cells with 100 and 500 μm hydralazine for 24 h increased absorbance (p < 0.05) in the standard MTS assay; however, trypan blue exclusion and microscopy suggested a decrease in cell numbers. In a cell-free system, hydralazine (100 and 500 μM) increased absorbance in a time- and concentration-dependent manner. The modified MTS assay produced results consistent with trypan blue exclusion and microscopy using THP-1 cells. In addition, the modified MTS assay produced reliable results when K562 and Jurkat cells were incubated with hydralazine or β-mercaptoethanol (βME). In conclusion, a simple modification of the standard MTS assay overcame the interference of hydralazine and βME when assessing suspended cells. © Copyright 2021, Mary Ann Liebert, Inc., publishers 2021. *Please note that there are multiple authors for this article therefore only the name of the Federation University Australia affiliates “Yutang Wang, Dinh Nguyen, Jack Anesi, Jason Kelly, Fahima Ahmady, Fadi Charchar" is provided in this record**

Establishment of sex difference in circulating uric acid is associated with higher testosterone and lower sex hormone-binding globulin in adolescent boys

- Wang, Yutang, Charchar, Fadi

  • Authors: Wang, Yutang , Charchar, Fadi
  • Date: 2021
  • Type: Text , Journal article
  • Relation: Scientific Reports Vol. 11, no. 1 (2021), p.
  • Relation: https://purl.org/au-research/grants/nhmrc/1062671
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  • Description: Men have higher circulating levels of uric acid than women. This sex difference is suspected to be a result of suppressive effects of estradiol on uric acid. If so, estradiol would be inversely associated with circulating uric acid. This study aimed to test this hypothesis. This cross-sectional study included 9472 participants (weighted sample size of 184,342,210) aged 12–80 years from the 2013 to 2016 US National Health and Nutrition Examination Survey. Associations of sex hormones with uric acid were analyzed using weighted least squares regression, adjusting for demographic characteristics, lifestyle risk factors, and comorbidities. Neither free nor bioavailable estradiol was inversely associated with circulating uric acid in adolescent boys or girls, or adult men or women, or perimenopausal women after full adjustment. The sex difference in uric acid was established during adolescence as a result of a dramatic increase in uric acid in adolescent boys. During adolescence, the increase in estradiol in girls over time was accompanied by a relatively unchanged level of uric acid. All three fractions of estradiol (free, bioavailable, and total) were positively associated with uric acid in adolescent boys and girls after full adjustment. In adolescent boys, all three fractions of testosterone were positively associated with serum uric acid, and sex hormone-binding globulin was inversely associated with uric acid after full adjustment. These results suggest that estradiol is not inversely associated with circulating uric acid in adolescents and the establishment of sex difference in circulating uric acid during adolescence is associated with higher testosterone and lower sex hormone-binding globulin in adolescent boys. © 2021, The Author(s).

Plasma lipocalin-2/NGAL is stable over 12 weeks and is not modulated by exercise or dieting

- Nakai, Michael, Prestes, Priscilla, O’Brien, Brendan, Charchar, Fadi, Marques, Francine

  • Authors: Nakai, Michael , Prestes, Priscilla , O’Brien, Brendan , Charchar, Fadi , Marques, Francine
  • Date: 2021
  • Type: Text , Journal article
  • Relation: Scientific Reports Vol. 11, no. 1 (2021), p.
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  • Description: Amongst other immune cells, neutrophils play a key role in systemic inflammation leading to cardiovascular disease and can release inflammatory factors, including lipocalin-2 (LCN2). LCN2 drives cardiac hypertrophy and plays a role in maladaptive remodelling of the heart and has been associated with renal injury. While lifestyle factors such as diet and exercise are known to attenuate low-grade inflammation, their ability to modulate plasma LCN2 levels is unknown. Forty-eight endurance athletes and 52 controls (18–55 years) underwent measurement for various cardiovascular health indicators, along with plasma LCN2 concentration. No significant difference in LCN2 concentration was seen between the two groups. LCN2 was a very weak predictor or absent from models describing blood pressures or predicting athlete status. In another cohort, 57 non-diabetic overweight or obese men and post-menopausal women who fulfilled Adult Treatment Panel III metabolic syndrome criteria were randomly allocated into either a control, modified Dietary Approaches to Stop Hypertension (DASH) diet, or DASH and exercise group. Pre- and post-intervention demographic, cardiovascular health indicators, and plasma LCN2 expression were measured in each individual. While BMI fell in intervention groups, LCN2 levels remained unchanged within and between all groups, as illustrated by strong correlations between LCN2 concentrations pre- and 12 weeks post-intervention (r = 0.743, P < 0.0001). This suggests that circulating LCN2 expression are stable over a period of at least 12 weeks and is not modifiable by diet and exercise. © 2021, The Author(s). *Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Priscilla Prestes, Brendan O'Brien, Fadi Charchar and Francine Marques” is provided in this record** .

Reduced renal function may explain the higher prevalence of hyperuricemia in older people

- Wang, Yutang, Zhang, Wanlin, Qian, Tingting, Sun, Hui, Xu, Qun, Hou, Xujuan, Hu, Wenqi, Zhang, Guang, Drummond, Grant, Sobey, Chris, Charchar, Fadi, Golledge, Jonathan, Yang, Guang

  • Authors: Wang, Yutang , Zhang, Wanlin , Qian, Tingting , Sun, Hui , Xu, Qun , Hou, Xujuan , Hu, Wenqi , Zhang, Guang , Drummond, Grant , Sobey, Chris , Charchar, Fadi , Golledge, Jonathan , Yang, Guang
  • Date: 2021
  • Type: Text , Journal article
  • Relation: Scientific Reports Vol. 11, no. 1 (2021), p.
  • Relation: https://purl.org/au-research/grants/nhmrc/1062671
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  • Description: This study aimed to investigate the contribution of renal dysfunction to enhanced hyperuricemia prevalence in older people. A cohort of 13,288 Chinese people aged between 40 and 95 years were recruited from January to May 2019. Serum uric acid concentration and estimated glomerular filtration rate [eGFR] were measured. The associations between age or eGFR and serum uric acid or hyperuricemia were analyzed using linear or binary logistic regression adjusting for risk factors. Uric acid concentration and prevalence of hyperuricemia were greater in older participants. Adjustment for reduced renal function (eGFR < 60 mL/min/1.73 m2) eliminated the associations between older age and higher uric acid concentration and between older age and higher prevalence of hyperuricemia diagnosis, whereas adjustment for other risk factors did not change those associations. Lower eGFR was associated with higher uric acid concentration both before (β = − 0.296, P < 0.001) and after adjustment for age (β = − 0.313, P < 0.001). Reduced renal function was associated with hyperuricemia diagnosis both before (odds ratio, OR, 3.64; 95% CI 3.10–4.28; P < 0.001) and after adjustment for age (adjusted OR, 3.82; 95% CI 3.22–4.54; P < 0.001). Mean serum uric acid and prevalence of hyperuricemia were higher in people with eGFR < 60 mL/min/1.73 m2 than those with eGFR ≥ 60 mL/min/1.73 m2. The prevalence of reduced renal function increased with older age (P < 0.001). This study suggests that reduced renal function can explain the increased uric acid levels and hyperuricemia diagnoses in older people. © 2021, The Author(s).

Uncovering genetic mechanisms of hypertension through multi-omic analysis of the kidney

- Eales, James, Jiang, Xiao, Xu, Xiaoguang, Prestes, Priscilla, Charchar, Fadi

  • Authors: Eales, James , Jiang, Xiao , Xu, Xiaoguang , Prestes, Priscilla , Charchar, Fadi
  • Date: 2021
  • Type: Text , Journal article
  • Relation: Nature Genetics Vol. 53, no. 5 (2021), p. 630-637
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  • Description: The kidney is an organ of key relevance to blood pressure (BP) regulation, hypertension and antihypertensive treatment. However, genetically mediated renal mechanisms underlying susceptibility to hypertension remain poorly understood. We integrated genotype, gene expression, alternative splicing and DNA methylation profiles of up to 430 human kidneys to characterize the effects of BP index variants from genome-wide association studies (GWASs) on renal transcriptome and epigenome. We uncovered kidney targets for 479 (58.3%) BP-GWAS variants and paired 49 BP-GWAS kidney genes with 210 licensed drugs. Our colocalization and Mendelian randomization analyses identified 179 unique kidney genes with evidence of putatively causal effects on BP. Through Mendelian randomization, we also uncovered effects of BP on renal outcomes commonly affecting patients with hypertension. Collectively, our studies identified genetic variants, kidney genes, molecular mechanisms and biological pathways of key relevance to the genetic regulation of BP and inherited susceptibility to hypertension. © 2021, Crown.

2020 International Society of Hypertension global hypertension practice guidelines

- Unger, Thomas, Borghi, Claudio, Charchar, Fadi, Khan, Nadia, Poulter, Neil, Prabhakaran, Dorairaj, Ramirez, Agustin, Schlaich, Markus, Stergiou, George, Tomaszewski, Maciej, Wainford, Richard, Williams, Bryan, Schutte, Aletta

A guide to the short, long and circular RNAs in hypertension and cardiovascular disease

- Prestes, Priscilla, Maier, Michelle, Woods, Bradley, Charchar, Fadi

  • Authors: Prestes, Priscilla , Maier, Michelle , Woods, Bradley , Charchar, Fadi
  • Date: 2020
  • Type: Text , Journal article , Review
  • Relation: International Journal of Molecular Sciences Vol. 21, no. 10 (2020)
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  • Description: Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in adults in developed countries. CVD encompasses many diseased states, including hypertension, coronary artery disease and atherosclerosis. Studies in animal models and human studies have elucidated the contribution of many genetic factors, including non-coding RNAs. Non-coding RNAs are RNAs not translated into protein, involved in gene expression regulation post-transcriptionally and implicated in CVD. Of these, circular RNAs (circRNAs) and microRNAs are relevant. CircRNAs are created by the back-splicing of pre-messenger RNA and have been underexplored as contributors to CVD. These circRNAs may also act as biomarkers of human disease, as they can be extracted from whole blood, plasma, saliva and seminal fluid. CircRNAs have recently been implicated in various disease processes, including hypertension and other cardiovascular disease. This review article will explore the promising and emerging roles of circRNAs as potential biomarkers and therapeutic targets in CVD, in particular hypertension. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

An improved 3-(4,5-dmethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl )-2H-tetrazolium proliferation assay to overcome the interference of hydralazine

- Wang, Yutang, Nguyen, Dinh, Yang, Guang, Anesi, Jack, Chai, Zhonglin, Charchar, Fadi, Golledge, Jonathan

  • Authors: Wang, Yutang , Nguyen, Dinh , Yang, Guang , Anesi, Jack , Chai, Zhonglin , Charchar, Fadi , Golledge, Jonathan
  • Date: 2020
  • Type: Text , Journal article
  • Relation: Assay and Drug Development Technologies Vol. 18, no. 8 (Dec 2020), p. 379-384
  • Relation: https://purl.org/au-research/grants/nhmrc/1062671
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  • Description: The MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay is one of the most commonly used assays to assess cell proliferation and cytotoxicity, but is subject to interference by testing compounds. Hydralazine, an antihypertensive drug, is commonly investigated in multiple fields such as heart failure, cancer, and blood pressure research. This study reported interference of the MTS assay by hydralazine and a simple modification overcoming this interference. Vascular smooth muscle cells were cultured in the presence or absence of hydralazine (0, 10, 50,100, and 500 mu M) for 2 or 24 h. Cell numbers were analyzed using MTS, trypan blue exclusion, or microscopic assays. A modified version of the standard MTS assay was established, in which an additional step was added replacing the test medium, containing hydralazine, with fresh culture medium immediately before the addition of the MTS reagent. Culture with hydralazine at concentrations of 50, 100, and 500 mu M for 2 h increased absorbance (p< 0.05) in the standard MTS assay, whereas microscopy suggested no change in cell numbers. Culture with 500 mu m hydralazine for 24 h increased absorbance (p< 0.05) in the standard MTS assay, however, trypan blue exclusion and microscopy suggested a decrease in cell numbers. In a cell-free system, hydralazine (>= 10 mu M) increased absorbance in a concentration-dependent manner. The modified MTS assay produced results consistent with trypan blue exclusion and microscopy. In conclusion, a simple modification of the standard MTS assay overcame the interference of hydralazine and may be useful to avoid interference from other tested compounds.

Discovery of rare variants associated with blood pressure regulation through meta-analysis of 1.3 million individuals

- Surendran, Praveen, Feofanova, Elena, Lahrouchi, Najim, Ntalla, Ionna, Karthikeyan, Savita, Cook, James, Chen, Lingyan, Mifsud, Borbala, Yao, Chen, Kraja, Aldi, Cartwright, James, Hellwege, Jacklyn, Giri, Ayush, Tragante, Vinicius, Thorleifsson, Gudmar, Liu, Dajiang, Prins, Bram, Stewart, Isobel, Cabrera, Claude, Eales, James, Akbarov, Artur, Auer, Paul, Charchar, Fadi, Howson, Joanna, LifeLines Cohort, Study, Epic, C. V. D., Epic InterAct, Understanding Society Scientific, Group, Million Veteran, Program

Highlights from the International Society of Hypertension's New Investigators Network during 2019

- Kruger, Ruan, Brunström, Mattias, Burger, Dylan, Charchar, Fadi, Climie, Rachel, Mirabito, Colafell, Kempny, Katrina, Korostovtseva, Lyudimila, Marques, Francine, Picone, Dean, Romero, Cesar, Steckelings, Ulrike, Velkoska, Elena, Wainford, Richard, Wynne, Brandi, Zanuzzi, Matias

Hypertension and renin-angiotensin system blockers are not associated with expression of angiotensin-converting enzyme 2 (ACE2) in the kidney

- Jiang, Xiao, Eales, James, Scannali, David, Prestes, Priscilla, Charchar, Fadi

  • 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

- 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

Neural suppression of miRNA-181a in the kidney elevates renin expression and exacerbates hypertension in Schlager mice

- Jackson, Kristy, Gueguen, Cindy, Lim, Kyungjoon, Eikelis, Nina, Stevenson, Emily, Charchar, Fadi, Lambert, Gavin, Burke, Sandra, Paterson, Madeleine, Marques, Francine, Head, Geoffrey

  • 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 association between selected molecular biomarkers and ambulatory blood pressure patterns in African chronic kidney disease and hypertensive patients compared with normotensive controls : protocol for a longitudinal study

- Adeoye, Abiodun, Adebayo, Oladimeji, Abiola, Busayo, Iwalokun, Bamidele, Tayo, Bamidele, Charchar, Fadi, Ojo, Akinlolu, Cooper, Richard

  • Authors: Adeoye, Abiodun , Adebayo, Oladimeji , Abiola, Busayo , Iwalokun, Bamidele , Tayo, Bamidele , Charchar, Fadi , Ojo, Akinlolu , Cooper, Richard
  • Date: 2020
  • Type: Text , Journal article
  • Relation: JMIR Research Protocols Vol. 9, no. 1 (Jan 2020), p. 8
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  • Description: Background: Chronic kidney disease (CKD) is a burgeoning epidemic in sub-Saharan Africa. Abnormal blood pressure variations are prevalent in CKD and potentiate the risk of cardiovascular morbidity and mortality. Certain genetic variants (angiotensin II receptor type 1 1166 A>C and angiotensin-converting enzyme insertion and deletion polymorphisms) and biomarkers such as interleukin-6, tumor necrosis factor, soluble (s) E-selectin, homocysteine, and highly sensitive C-reactive protein have been shown to affect blood pressure variability among non-African CKD, hypertensive. and nonhypertensive CKD population. However, the contributions of the pattern, genetic, and environmental determinants of ambulatory blood pressure in African CKD have not been characterized. Understanding these interactions may help to develop interventions to prevent major cardiovascular events among people with CKD. Objective: The overarching objective of this study is to identify, document, and develop approaches to address related phenomic, genetic, and environmental determinants of ambulatory blood pressure patterns in African CKD and non-CKD hypertensive patients compared with normotensive controls. Methods: This is a longitudinal short-term follow-up study of 200 adult subjects with CKD and 200 each of age-matched hypertensives without CKD and apparently healthy controls. Demographic information, detailed clinical profile, electrocardiography, echocardiography, and 24-hr ambulatory blood pressure measurements will be obtained. Blood samples will be collected to determine albumin-creatinine ratio, fasting plasma glucose, lipid profile, electrolytes, urea and creatinine, C-reactive protein, serum homocysteine, fibroblast growth factor-23, and complete blood count, while 2 mL blood aliquot will be collected in EDTA (ethylenediaminetetraacetic acid) tubes and mixed using an electronic rolling system to prevent blood clots and subsequently used for DNA extraction and genetic analysis. Results: A total of 239 participants have been recruited so far, and it is expected that the recruitment phase will be complete in June 2020. The follow-up phase will continue with data analysis and publications of results. Conclusions: This study will help stratify Nigerian CKD patients phenotypically and genotypically in terms of their blood pressure variations with implications for targeted interventions and timing of medications to improve prognosis.

DNA copy number variations – Do these big mutations have a big effect on cardiovascular risk?

- Prestes, Priscilla, Maier, Michelle, Charchar, Fadi

  • Authors: Prestes, Priscilla , Maier, Michelle , Charchar, Fadi
  • Date: 2019
  • Type: Text , Journal article , Editorial
  • Relation: International Journal of Cardiology Vol. 298, no. (2019), p. 116-117
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  • Description: In simple terms, copy number variations or CNVs are replications or deletions in the DNA which, in humans, changes it from the normal number of two gene copies. These CNVs are caused by inherited or de novo structural changes such as duplications, insertions or deletions of repeated portions of genetic material (Fig. 1). These duplications can vary from one to ten or more copies and range in size from 50 DNA base pairs to several million [1]. Since their discovery in 1987 by Nakamura et al. [2], when they were initially named variable number tandem repeats, many studies have investigated their association with rare and common human diseases. Throughout evolution, some of these changes in copy number were beneficial such as the globin gene number duplication, while others such as the CNVs that cause Huntington's disease were not. In 2004, two landmark studies by Iafrate et al. [3] and Sebat et al. [4] found that large-scale copy-number variations, ranging in size from 100 kb to 2 Mb are common throughout the human genome, and that a high proportion of them are in known genes. These findings roused several association studies between CNVs and disease

Human Y Chromosome Exerts Pleiotropic Effects on Susceptibility to Atherosclerosis

- Eales, James, Maan, Akhlaq, Xu, Xiaoguang, Michoel, Tom, Hallast, Pille, Batini, C, Zadik, Daniel, Prestes, Priscilla, Molina, Elsa, Denniff, Matthew, Schroeder, Juliane, Bjorkegren, Johan, Thompson, John, Maffia, Pasquale, Guzik, Tomasz, Keavney, Bernard, Jobling, Mark, Samani, Nilesh, Charchar, Fadi, Tomaszewski, Maciej

  • Authors: Eales, James , Maan, Akhlaq , Xu, Xiaoguang , Michoel, Tom , Hallast, Pille , Batini, C , Zadik, Daniel , Prestes, Priscilla , Molina, Elsa , Denniff, Matthew , Schroeder, Juliane , Bjorkegren, Johan , Thompson, John , Maffia, Pasquale , Guzik, Tomasz , Keavney, Bernard , Jobling, Mark , Samani, Nilesh , Charchar, Fadi , Tomaszewski, Maciej
  • Date: 2019
  • Type: Text , Journal article
  • Relation: Arteriosclerosis, thrombosis, and vascular biology Vol. 39, no. 11 (2019), p. 2386-2401
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  • Description: OBJECTIVE: The male-specific region of the Y chromosome (MSY) remains one of the most unexplored regions of the genome. We sought to examine how the genetic variants of the MSY influence male susceptibility to coronary artery disease (CAD) and atherosclerosis. Approach and Results: Analysis of 129 133 men from UK Biobank revealed that only one of 7 common MSY haplogroups (haplogroup I1) was associated with CAD-carriers of haplogroup I1 had ≈11% increase in risk of CAD when compared with all other haplogroups combined (odds ratio, 1.11; 95% CI, 1.04-1.18; P=6.8×10-4). Targeted MSY sequencing uncovered 235 variants exclusive to this haplogroup. The haplogroup I1-specific variants showed 2.45- and 1.56-fold respective enrichment for promoter and enhancer chromatin states, in cells/tissues relevant to atherosclerosis, when compared with other MSY variants. Gene set enrichment analysis in CAD-relevant tissues showed that haplogroup I1 was associated with changes in pathways responsible for early and late stages of atherosclerosis development including defence against pathogens, immunity, oxidative phosphorylation, mitochondrial respiration, lipids, coagulation, and extracellular matrix remodeling. UTY was the only Y chromosome gene whose blood expression was associated with haplogroup I1. Experimental reduction of UTY expression in macrophages led to changes in expression of 59 pathways (28 of which overlapped with those associated with haplogroup I1) and a significant reduction in the immune costimulatory signal. CONCLUSIONS: Haplogroup I1 is enriched for regulatory chromatin variants in numerous cells of relevance to CAD and increases cardiovascular risk through proatherosclerotic reprogramming of the transcriptome, partly through UTY.

May measurement month 2018 : A pragmatic global screening campaign to raise awareness of blood pressure by the international society of hypertension

- 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

  • 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

- Gueguen, Cindy, Jackson, Kristy, Marques, Francine, Eikelis, Nina, Phillips, Sarah, Stevenson, Emily, Charchar, Fadi, Lambert, Gavin, Davern, Pamela, Head, Geoffrey

  • 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.

Trans-ethnic kidney function association study reveals putative causal genes and effects on kidney-specific disease aetiologies

- Morris, Andrew, Le, Thu, Wu, Haojia, Akbarov, Artur, van der Most, Peter, Hemani, Gibran, Smith, George, Mahajan, Anubha, Gaulton, Kyle, Nadkarni, Girish, Valladares-Salgado, Adan, Wacher-Rodarte, Niels, Mychaleckyj, Josyf, Dueker, Nicole, Guo, Xiuqing, Hai, Yang, Haessler, Jeffrey, Kamatani, Yoichiro, Stilp, Adrienne, Zhu, Gu, Cook, James, Arnlov, Johan, Blanton, Susan, de Borst, Martin, Bottinger, Erwin, Buchanan, Thomas, Cechova, Sylvia, Charchar, Fadi, Chu, Pei-Lun, Damman, Jeffrey, Eales, James, Gharavi, Ali, Giedraitis, Vilmantas, Heath, Andrew, Ipp, Eli, Kiryluk, Krzysztof, Kramer, Holly, Kubo, Michiaki, Larsson, Anders, Lindgren, Cecilia, Lu, Yingchang, Madden, Pamela, Montgomery, Grant, Papanicolaou, George, Raffel, Leslie, Sacco, Ralph, Sanchez, Elena, Stark, Holger, Sundstrom, Johan, Taylor, Kent, Xiang, Anny, Zivkovic, Aleksandra, Lind, Lars, Ingelsson, Erik, Martin, Nicholas, Whitfield, John, Cai, Jianwen, Laurie, Cathy, Okada, Yukinori, Matsuda, Koichi, Kooperberg, Charles, Chen, Yii-Der, Rundek, Tatjana, Rich, Stephen, Loos, Ruth, Parra, Esteban, Cruz, Miguel, Rotter, Jerome, Snieder, Harold, Tomaszewski, Maciej, Humphreys, Benjamin, Franceschini, Nora

Uncovering genetic mechanisms of kidney aging through transcriptomics, genomics, and epigenomics

- Rowland, Joshua, Akbarov, Artur, Eales, James, Xu, Xiaoguang, Dormer, John, Guo, Hui, Denniff, Matthew, Jiang, Xiao, Ranjzad, Parisa, Nazgiewicz, Alicja, Prestes, Priscilla, Antczak, Andrzej, Szulinska, Monika, Wise, Ingrid, Zukowska-Szczechowska, Ewa, Bogdanski, Pawel, Woolf, Adrian, Samani, Nilesh, Charchar, Fadi, Tomaszewski, Maciej

  • Authors: Rowland, Joshua , Akbarov, Artur , Eales, James , Xu, Xiaoguang , Dormer, John , Guo, Hui , Denniff, Matthew , Jiang, Xiao , Ranjzad, Parisa , Nazgiewicz, Alicja , Prestes, Priscilla , Antczak, Andrzej , Szulinska, Monika , Wise, Ingrid , Zukowska-Szczechowska, Ewa , Bogdanski, Pawel , Woolf, Adrian , Samani, Nilesh , Charchar, Fadi , Tomaszewski, Maciej
  • Date: 2019
  • Type: Text , Journal article
  • Relation: Kidney International Vol. 95, no. 3 (2019), p. 624-635
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  • Description: Nephrons scar and involute during aging, increasing the risk of chronic kidney disease. Little is known, however, about genetic mechanisms of kidney aging. We sought to define the signatures of age on the renal transcriptome using 563 human kidneys. The initial discovery analysis of 260 kidney transcriptomes from the TRANScriptome of renaL humAn TissuE Study (TRANSLATE) and the Cancer Genome Atlas identified 37 age-associated genes. For 19 of those genes, the association with age was replicated in 303 kidney transcriptomes from the Nephroseq resource. Surveying 42 nonrenal tissues from the Genotype–Tissue Expression project revealed that, for approximately a fifth of the replicated genes, the association with age was kidney-specific. Seventy-three percent of the replicated genes were associated with functional or histological parameters of age-related decline in kidney health, including glomerular filtration rate, glomerulosclerosis, interstitial fibrosis, tubular atrophy, and arterial narrowing. Common genetic variants in four of the age-related genes, namely LYG1, PPP1R3C, LTF and TSPYL5, correlated with the trajectory of age-related changes in their renal expression. Integrative analysis of genomic, epigenomic, and transcriptomic information revealed that the observed age-related decline in renal TSPYL5 expression was determined both genetically and epigenetically. Thus, this study revealed robust molecular signatures of the aging kidney and new regulatory mechanisms of age-related change in the kidney transcriptome.