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The exclusive expression of uromodulin in the kidneys has made it an intriguing protein in kidney and cardiovascular research. Genome-wide association studies discovered variants of uromodulin that are associated with chronic kidney diseases and hypertension. Urinary and circulating uromodulin levels reflect kidney and cardiovascular health as well as overall mortality. More recently, Mendelian randomization studies have shown that genetically driven levels of uromodulin have a causal and adverse effect on kidney function. On a mechanistic level, salt sensitivity is an important factor in the pathophysiology of hypertension, and uromodulin is involved in salt reabsorption via the NKCC2 (Na + -K + -2Cl − cotransporter) on epithelial cells of the ascending limb of loop of Henle. In this review, we provide an overview of the multifaceted physiology and pathophysiology of uromodulin including recent advances in its genetics; cellular trafficking; and mechanistic and clinical studies undertaken to understand the complex relationship between uromodulin, blood pressure, and kidney function. We focus on tubular sodium reabsorption as one of the best understood and pathophysiologically and clinically most important roles of uromodulin, which can lead to therapeutic interventions.

Runt-related transcription factor-1 (RUNX1), also known as acute myeloid leukaemia 1 protein (AML1), is a member of the core-binding factor family of transcription factors which modulate cell proliferation, differentiation, and survival in multiple systems. It is a master-regulator transcription factor, which has been implicated in diverse signalling pathways and cellular mechanisms during normal development and disease. RUNX1 is best characterized for its indispensable role for definitive haematopoiesis and its involvement in haematological malignancies. However, more recently RUNX1 has been identified as a key regulator of adverse cardiac remodelling following myocardial infarction. This review discusses the role RUNX1 plays in the heart and highlights its therapeutic potential as a target to limit the progression of adverse cardiac remodelling and heart failure.

Using a genome wide association study (GWAS), we identified a locus on the promoter of the human uromodulin (UMOD) gene associating with primary hypertension. In this study we aimed to identify genotype-differential protein binding partners which influence UMOD expression and to examine pathways linking UMOD expression to blood pressure variability in humans.We examined a variant on this locus, by incubating 50mer oligonucleotides featuring alternate alleles (C/G) with HEK-293 nuclear protein extract. Subsequently, we performed an electrophoretic mobility shift assay (EMSA) and purified protein complexes to analyse by Tandem-mass-spectroscopy (MS2). Filtering for peptide matches >20, we interpreted these data by Ingenuity Pathway Analysis (IPA). From a bank of 98 human renal biopsy samples, we assessed UMOD expression by qRT-PCR. RNA-seq was performed using the NextSeq-500 system on a subset of high and low UMOD expressors (n=3/ group). Differentially expressed (false-discovery-rate (FDR)

During pregnancy, the uterine spiral arteries undergo major vascular remodeling to ensure sufficient uteroplacental perfusion to support the fetus. In pregnancies complicated by hypertensive disorders, this remodeling is deficient leading to impaired uteroplacental blood flow and poor maternal and fetal outcomes. The underlying genetic mechanisms for failed vascular remodeling are not fully understood. This study aimed to examine the early-pregnancy-associated gene changes in the uterine arteries of spontaneously hypertensive stroke-prone rats (SHRSP) compared with their normotensive counterparts, Wistar–Kyoto rats (WKY). Uterine arteries from gestational day 6.5 WKY and SHRSP were processed for RNA-sequencing, along with virgin, age-matched controls for each strain. Gene expression changes were identified and biological pathways were implicated and interpretated using ingenuity pathway analysis (IPA). This study found that WKY uterine arteries from early pregnancy exhibit a gene expression pattern that is suggestive of a pregnancy-dependent reduction in Ca2+ handling and renin-angiotensin-aldosterone system (RAAS) components and an increase in ATP production. In contrast, the expression pattern of pregnant SHRSP uterine arteries was dominated by an elevated immune response and increased production of reactive oxygen species (ROS) and downstream effectors of the RAAS. These results suggest that in a rat model, hypertension during pregnancy impacts uterine artery gene expression patterns as early as the first week of pregnancy. The pathway changes involved may underlie or contribute to the adverse vascular remodeling and resultant placental ischemia and systemic vascular dysfunction observed in SHRSP in late gestation.

Numerous molecular mechanisms have been implicated in processes underlying vascular phenotypic changes and alterations in hypertension, including microRNAs (miRNAs), oxidative stress and perturbed endoplasmic reticulum (ER) function. The interplay between these elements is unclear. We assessed the VSMC miRNAs profile in hypertension focusing on oxidative and ER stress pathways. VSMCs from small arteries from normotensive (NT) and hypertensive (HT) subjects were used. miRNA profiling of 758 miRNAs was performed using TaqMan advanced miRNA assay (TaqMan Low Density Array Human microRNA). Ingenuity Pathway Analysis (IPA) was used for miRNA target prediction. Expression of vascular genes and proteins was detected by RT-PCR and immunoblotting. ROS generation (chemiluminescence) was assessed in the absence and presence of ER stress inducer tunicamycin (5μg/ml, 24h). miRNA array identified 25 miRNAs uniquely expressed in HT and 21 miRNAs uniquely expressed in NT (CT1.5), while 136 miRNAs were significantly downregulated in HT (fold change >1.5). miRNAs that were altered in hypertension, targeted genes involved in oxidative and ER stress. Pro-oxidant [Nox1 mRNA (1.71 fold), Nox4 (1.59 fold), Nox5 (2.04 fold)] and antioxidant [SOD2 mRNA (4.43 fold), GPx1 (1.97 fold)] enzymes protein levels upregulated in HT (p

Placental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.

Supplemental Digital Content is available in the text., Hypertensive disorders of pregnancy are the second leading cause of maternal deaths worldwide. Superimposed preeclampsia is an increasingly common problem and often associated with impaired placental perfusion. Understanding the underlying mechanisms and developing treatment options are crucial. The pregnant stroke-prone spontaneously hypertensive rat has impaired uteroplacental blood flow and abnormal uterine artery remodeling. We used Ang II (angiotensin II) infusion in pregnant stroke-prone spontaneously hypertensive rats to mimic the increased cardiovascular stress associated with superimposed preeclampsia and examine the impact on the maternal cardiovascular system and fetal development. Continuous infusion of Ang II at 500 or 1000 ng/kg per minute was administered from gestational day 10.5 until term. Radiotelemetry and echocardiography were used to monitor hemodynamic and cardiovascular changes, and urine was collected prepregnancy and throughout gestation. Uterine artery myography assessed uteroplacental vascular function and structure. Fetal measurements were made at gestational day 18.5, and placentas were collected for histological and gene expression analyses. The 1000 ng/kg per minute Ang II treatment significantly increased blood pressure (P

RationaleTransforming growth factor-beta (TGFβ) is tightly regulated at multiple levels, with regulation at the receptor level now recognized as a key determinant of the cellular response to this pleiotropic cytokine. TGFβ promotes saphenous vein graft neointima formation after coronary artery bypass graft (CABG) surgery, inducing smooth muscle cell (SMC) hyperplasia and fibrosis by signaling via activin receptor-like kinase 5(ALK5). However, the role of the alternate TGFβ receptor ALK1 remains completely unknown.ObjectiveTo define the receptor pathways activated by TGFβ in SMCs and their mechanistic importance during CABG neointima formation.Methods and resultsRadioligand co-IP assays revealed direct interactions between TGFβ, ALK5 and ALK1 in primary saphenous vein graft SMC (HSVSMC) from patients undergoing CABG. Knockdown and pharmacological inhibition of ALK5 or ALK1 in HSVSMC significantly attenuated TGFβ-induced phosphorylation of receptor-regulated (R)-Smads 2/3 and 1/5, respectively. Microarray profiling followed by qRT-PCR validation showed that TGFβ induced distinct transcriptional networks downstream of ALK5 or ALK1, associated with HSVSMC contractility and migration, respectively and confirmed using migration assays as well as qRT-PCR and western blot assays of contractile SMC markers. scRNAseq analysis of TGFβ-treated HSVSMC identified distinct subgroups of cells showing ALK5 or ALK1 transcriptional responses, while RNA velocity analyses indicated divergence in differentiation towards ALK5 or ALK1-dominant lineages. ALK1, ALK5 and their downstream effectors pSmad1/5 and pSmad2/3 were localized to αSMA+ neointimal SMCs in remodelled mouse vein grafts. Pharmacological inhibition or genetic ablation of Smad1/5 substantially reducing neointima formation following acute vascular injury. Notably, expression and activation of ALK1, ALK5 and their respective downstream R-Smads was already evident in hyperplastic saphenous veins prior to grafting.ConclusionsWhilst canonical TGFβ signaling via ALK5 promotes a contractile HSVSMC phenotype, transactivation of ALK1 by TGFβ induces neointima formation by driving cell migration. Restoring the balance between ALK1 and ALK5 in HSVSMC may represent a novel therapeutic strategy for vein graft failure.

Objective: To explore putative different impacts of delayed graft function(DGF) on long-term graft survival in kidneys donated after brain death (DBD)and circulatory death (DCD).Background: Despite a 3-fold higher incidence of DGF in DCD grafts, largestudies show equivalent long-term graft survival for DBD and DCD grafts.This observation implies a differential impact of DGF on DBD and DCD graftsurvival. The contrasting impact is remarkable and yet unexplained.Methods: The impact of DGF on DBD and DCD graft survival was evaluatedin 6635 kidney transplants performed in The Netherlands. DGF severity andfunctional recovery dynamics were assessed for 599 kidney transplantsperformed at the Leiden Transplant Center. Immunohistochemical staining,gene expression profiling, and Ingenuity Pathway Analysis were used toidentify differentially activated pathways in DBD and DCD grafts.Results: While DGF severely impacted 10-year graft survival in DBD grafts(HR 1.67; P < 0.001), DGF did not impact graft survival in DCD grafts (HR1.08; P ¼ 0.63). Shorter dialysis periods and superior posttransplant eGFRs inDBD grafts show that the differential impact was not caused by a more severeDGF phenotype in DBD grafts. Immunohistochemical evaluation indicatesthat pathways associated with tissue resilience are present in kidney grafts.Molecular evaluation showed selective activation of resilience-associatedpathways in DCD grafts.Conclusions: This study shows an absent impact of DGF on long-term graftsurvival in DCD kidneys. Molecular evaluation suggests that the differentialimpact of DGF between DBD and DCD grafts relates to donor-type specificactivation of resilience pathways in DCD grafts.

In BriefInterleukine-1 beta (IL-1β) has been identified as a critical factor that contributes to the inflammatory response in cardiovascular disease (e.g., atherosclerosis). Pannexin 1 (Panx1) channel activity in endothelial cells regulates localized inflammatory cell recruitment. In response to prolonged tumor necrosis factor alpha (TNF) treatment, Yang et al. found that the Panx1 channel is targeted to the plasma membrane, where it facilitates an increase in intracellular calcium to control the production and release of cytokines including IL-1β.GRAPHICAL ABSTRACTAbstractThe proinflammatory cytokine IL-1β is a significant risk factor in cardiovascular disease that can be targeted to reduce major cardiovascular events. IL-1β expression and release are tightly controlled by changes in intracellular Ca2+. In addition, purinergic signaling through ATP release has also been reported to promote IL-1β production. Despite this, the mechanisms that control IL-1β synthesis and expression have not been identified. The pannexin 1 (Panx1) channel has canonically been implicated in ATP release, especially during inflammation. However, resolution of purinergic signaling occurs quickly due to blood flow and the presence of ectonucleotidases. We examined Panx1 in human endothelial cells following treatment with the pro-inflammatory cytokine tumor necrosis alpha (TNF). In response to long-term TNF treatment, we identified a dramatic increase in Panx1 protein expression at the plasma membrane. Analysis by whole transcriptome sequencing (RNA-seq), qPCR, and treatment with specific kinase inhibitors, revealed that TNF signaling induced NFκβ-associated Panx1 transcription. Genetic inhibition of Panx1 reduced the expression and secretion of IL-1β. We initially hypothesized that increased Panx1-mediated ATP release acted in a paracrine fashion to control cytokine expression. However, our data demonstrate that IL1-β expression was not altered after direct ATP stimulation, following degradation of ATP by apyrase, or after pharmacological blockade of P2 receptors. These data suggest that non-purinergic pathways, involving Panx1, control IL-1β production. Because Panx1 forms a large pore channel, we hypothesized it may act to passively diffuse Ca2+ into the cell upon opening to regulate IL-1β. High-throughput flow cytometric analysis demonstrated that TNF treatments lead to elevated intracellular Ca2+. Genetic or pharmacological inhibition of Panx1 reduced TNF-associated increases in intracellular Ca2+, and IL-1β transcription. Furthermore, we found that the Ca2+-sensitive NFκβ-p65 protein failed to localize to the nucleus after genetic or pharmacological block of Panx1. Taken together, our study provides the first evidence that intracellular Ca2+ regulation via the Panx1 channel induces a feed-forward effect on NFκβ to regulate IL-1β synthesis and release in endothelium during inflammation.

Combined congenic breeding and microarray gene expression profiling previously identified glutathione S-transferase μ-type 1 (Gstm1) as a positional and functional candidate gene for blood pressure (BP) regulation in the stroke-prone spontaneously hypertensive (SHRSP) rat. Renal Gstm1 expression in SHRSP rats is significantly reduced when compared with normotensive Wistar Kyoto (WKY) rats. As Gstm1 plays an important role in the secondary defence against oxidative stress, significantly lower expression levels may be functionally relevant in the development of hypertension. The aim of this study was to investigate the role of Gstm1 in BP regulation and oxidative stress by transgenic overexpression of the Gstm1 gene.Two independent Gstm1 transgenic SHRSP lines were generated by microinjecting SHRSP embryos with a linear construct controlled by the EF-1α promoter encoding WKY Gstm1 cDNA [SHRSP-Tg(Gstm1)1 and SHRSP-Tg(Gstm1)2].Transgenic rats exhibit significantly reduced BP and pulse pressure when compared with SHRSP [systolic: SHRSP 205.2 ± 3.7 mmHg vs. SHRSP-Tg(Gstm1)1 175.5 ± 1.6 mmHg and SHRSP-Tg(Gstm1)2 172 ± 3.2 mmHg, P 0.001; pulse pressure: SHRSP 58.4 ± 0.73 mmHg vs. SHRSP-Tg(Gstm1)1 52.7 ± 0.19 mmHg and SHRSP-Tg(Gstm1)2 40.7 ± 0.53 mmHg, P 0.001]. Total renal and aortic Gstm1 expression in transgenic animals was significantly increased compared with SHRSP [renal relative quantification (RQ): SHRSP-Tg(Gstm1)1 1.95 vs. SHRSP 1.0, P 0.01; aorta RQ: SHRSP-Tg(Gstm1)1 2.8 vs. SHRSP 1.0, P 0.05]. Renal lipid peroxidation (malondialdehyde: protein) and oxidized : reduced glutathione ratio levels were significantly reduced in both transgenic lines when compared with SHRSP [malondialdehyde: SHRSP 0.04 ± 0.009 μmol/l vs. SHRSP-Tg(Gstm1)1 0.024 ± 0.002 μmol/l and SHRSP-Tg(Gstm1)2 0.021 ± 0.002 μmol/l; (oxidized : reduced glutathione ratio): SHRSP 5.19 ± 2.26 μmol/l vs. SHRSP-Tg(Gstm1)1 0.17 ± 0.11 μmol/l and SHRSP-Tg(Gstm1)2 0.47 ± 0.22 μmol/l]. Transgenic SHRSP rats containing the WKY Gstm1 gene demonstrate significantly lower BP, reduced oxidative stress and improved levels of renal Gstm1 expression.These data support the hypothesis that reduced renal Gstm1 plays a role in the development of hypertension.

Previously, our comprehensive cardiovascular characterization study validated Uromodulin as a blood pressure gene. Uromodulin is a glycoprotein exclusively synthesized at the thick ascending limb of the loop of Henle and is encoded by the Umod gene. Umod−/− mice have significantly lower blood pressure than Umod+/+ mice, are resistant to salt-induced changes in blood pressure, and show a leftward shift in pressure-natriuresis curves reflecting changes of sodium reabsorption. Salt stress triggers transcription factors and genes that alter renal sodium reabsorption. To date there are no studies on renal transcriptome responses to salt stress. Here we aimed use RNA-Seq to delineate salt stress pathways in tubules isolated from Umod+/+ mice (a model of sodium retention) and Umod−/− mice (a model of sodium depletion) ± 300 mosmol sodium chloride (n = 3 per group). In response to salt stress, the tubules of Umod+/+ mice displayed an upregulation of heat shock transcripts. The greatest changes occurred in the expression of: Hspa1a (Log2 fold change 4.35, P = 2.48 e−12) and Hspa1b (Log2 fold change 4.05, P = 2.48 e−12). This response was absent in tubules of Umod−/− mice. Interestingly, seven of the genes discordantly expressed in the Umod−/− tubules were electrolyte transporters. Our results are the first to show that salt stress in renal tubules alters the transcriptome, increasing the expression of heat shock genes. This direction of effect in Umod+/+ tubules suggest the difference is due to the presence of Umod facilitating greater sodium entry into the tubule cell reflecting a specific response to salt stress.

Rationale: The pathogenesis of pulmonary arterial hypertension (PAH) remains unclear. The 4 microRNAs representing the miR-143 and miR-145 stem loops are genomically clustered. Objective: To elucidate the transcriptional regulation of the miR-143/145 cluster and the role of miR-143 in PAH. Methods and Results: We identified the promoter region that regulates miR-143/145 microRNA expression in pulmonary artery smooth muscle cells (PASMCs). We mapped PAH-related signaling pathways, including estrogen receptor, liver X factor/retinoic X receptor, transforming growth factor-β (Smads), and hypoxia (hypoxia response element), that regulated levels of all pri-miR stem loop transcription and resulting microRNA expression. We observed that miR-143-3p is selectively upregulated compared with miR-143-5p during PASMC migration. Modulation of miR-143 in PASMCs significantly altered cell migration and apoptosis. In addition, we found high abundance of miR-143-3p in PASMC-derived exosomes. Using assays with pulmonary arterial endothelial cells, we demonstrated a paracrine promigratory and proangiogenic effect of miR-143-3p–enriched exosomes from PASMC. Quantitative polymerase chain reaction and in situ hybridization showed elevated expression of miR-143 in calf models of PAH and in samples from PAH patients. Moreover, in contrast to our previous findings that had not supported a therapeutic role in vivo, we now demonstrate a protective role of miR-143 in experimental pulmonary hypertension in vivo in miR-143−/− and anti-miR-143-3p–treated mice exposed to chronic hypoxia in both preventative and reversal settings. Conclusions: MiR-143-3p modulated both cellular and exosome-mediated responses in pulmonary vascular cells, whereas inhibition of miR-143-3p blocked experimental pulmonary hypertension. Taken together, these findings confirm an important role for the miR-143/145 cluster in PAH pathobiology.

Background Drug-eluting stents reduce the incidence of in-stent restenosis, but they result in delayed arterial healing and are associated with a chronic inflammatory response and hypersensitivity reactions. Identifying novel interventions to enhance wound healing and reduce the inflammatory response may improve long-term clinical outcomes. Micro–ribonucleic acids (miRNAs) are noncoding small ribonucleic acids that play a prominent role in the initiation and resolution of inflammation after vascular injury. Objectives This study sought to identify miRNA regulation and function after implantation of bare-metal and drug-eluting stents. Methods Pig, mouse, and in vitro models were used to investigate the role of miRNA in in-stent restenosis. Results We documented a subset of inflammatory miRNAs activated after stenting in pigs, including the miR-21 stem loop miRNAs. Genetic ablation of the miR-21 stem loop attenuated neointimal formation in mice post-stenting. This occurred via enhanced levels of anti-inflammatory M2 macrophages coupled with an impaired sensitivity of smooth muscle cells to respond to vascular activation. Conclusions MiR-21 plays a prominent role in promoting vascular inflammation and remodeling after stent injury. MiRNA-mediated modulation of the inflammatory response post-stenting may have therapeutic potential to accelerate wound healing and enhance the clinical efficacy of stenting.

Background: The effect of salt on cerebral small vessel disease (SVD) is poorly understood. We assessed the effect of dietary salt on cerebral tissue of the stroke-prone spontaneously hypertensive rat (SHRSP) – a relevant model of sporadic SVD – at both the gene and protein level. Methods: Brains from 21-week-old SHRSP and Wistar-Kyoto rats, half additionally salt-loaded (via a 3-week regime of 1% NaCl in drinking water), were split into two hemispheres and sectioned coronally – one hemisphere for mRNA microarray and qRT-PCR, the other for immunohistochemistry using a panel of antibodies targeting components of the neurovascular unit. Results: We observed differences in gene and protein expression affecting the acute phase pathway and oxidative stress (ALB, AMBP, APOH, AHSG and LOC100129193, up-regulated in salt-loaded WKY versus WKY, >2-fold), active microglia (increased Iba-1 protein expression in salt-loaded SHRSP versus salt-loaded WKY, p3-fold; CLDN-11, VEGF and VGF down-regulated >2-fold in salt-loaded SHRSP versus SHRSP) and myelin integrity (MBP down-regulated in salt loaded WKY rats versus WKY, >2.5-fold). Changes of salt-loading were more pronounced in SHRSP and occurred without an increase in blood pressure in WKY rats. Conclusion: Salt exposure induced changes in gene and protein expression in an experimental model of SVD and its parent rat strain in multiple pathways involving components of the glio-vascular unit. Further studies in pertinent experimental models at different ages would help clarify the short- and long-term effect of dietary salt in SVD.

Background: Hypertensive disorders of pregnancy are a leading cause of maternal mortality worldwide. Chronic hypertension with superimposed preeclampsia is becoming more prevalent in modern society. Animal models are vital for understanding this condition. Our aim was to induce a preeclamptic phenotype in pregnant stroke prone spontaneously hypertensive (SHRSP) rats by angiotensin II (AngII) infusion. Methods: AngII, at a dose of 500ng/kg/min or 1000ng/kg/min, was administered by minipump in pregnant SHRSP rats from gestational day (GD)10. Cardiovascular and renal changes were monitored using radiotelemetry, echocardiography and weekly urine collections. GD18 ex vivo uterine artery function and structure were assessed using myography. Results: Both AngII doses resulted in an immediate and sustained increase in systolic blood pressure compared to vehicle control ( 172.5±5.0mmHg; 500ng/kg/min and 204.1±5.6mmHg; 1000ng/kg/min vs 159.0±0.4mmHg; p ). Cardiac output increased over pregnancy in the vehicle group ( 53±6L/min vs 81±5L/min; p ), however this trend was not observed in 500ng/kg/min treatment group ( 60±6L/min vs 56±11L/min ) and was reversed in 1000ng/kg/min treatment group ( 60±6L/min vs 36±6L/min; p ). GD14 urinary albumin:creatinine ratios were significantly increased in both treatment groups ( 1.3±0.2; 500ng/kg/min, 2.9±0.1; 1000ng/kg/min vs 0.5±0.2; vehicle; p ). Uterine arteries in the 1000ng/kg/min treatment group demonstrated significantly reduced cross-sectional area ( 4.8x10 4 ±32μm 2 vs 7.6x10 4 ±16μm 2 ; p ). Both treatment groups had a reduced vasorelaxation to 2x10 5 M carbachol ( 93.6±3.9%; 500ng/kg/min, 84.7±4.3%; 1000ng/kg/min vs 56.9±21.1%; vehicle; p ) and contractile response to 2x10 5 M noradrenaline demonstrated an increased trend in both treatment groups ( 66.9±16.1KPa; 500ng/kg/min, 61.8±6.2KPa; 1000ng/kg/min vs 45.1±5.7KPa; vehicle ). Conclusion: This study demonstrates that AngII infusion in pregnant SHRSP rats can mimic specific haemodynamic, cardiac and urinary profiles common to preeclamptic women. This rodent model of superimposed preeclampsia will be crucial for detailed investigation of underlying causes and treatment options for this condition.

Background: During normal pregnancy the uteroplacental vasculature remodels to accommodate for the increased blood flow to the placenta. In hypertensive pregnancies this remodelling is impaired. Stroke prone spontaneously hypertensive (SHRSP) rats exhibit a hypertensive pregnancy with impaired uteroplacental remodelling. This study investigated early gene expression changes in the uterine arteries (UA) of pregnant SHRSP and normotensive Wistar Kyoto (WKY) rats. Methods: SHRSP and WKY females were time mated and UA isolated at gestational day (GD)6 (n=3). Non-pregnant (NP) UA were isolated from virgin aged matched controls (n=3). UA RNAseq (Illumina platform) was performed. Transcript level gene changes were interpreted using Ingenuity Pathway Analysis (FDR < 0.05, FPKM>1.0). Quantitative RT-PCR was used to validate significantly differentially expressed genes. Results: There was a greater number of differentially expressed transcripts NP v GD6 in SHRSP compared to WKY (796 vs 535). 147 pregnancy dependant gene changes were common to SHRSP and WKY; which involved cellular movement and cell growth/proliferation pathways. Further analysis revealed calcium signalling genes involved in the α-adrenergic pathway were downregulated in WKY NP v GD6, e.g. inositol-1,4,5-trisphosphate receptor (Ip3r) ( FC 2.5; p , but were not different in SHRSP. Inflammatory response was increased over pregnancy, specifically phospholipase A2 (Pla2ga) expression ( FC -7.2 in WKY and FC -4.3 in SHRSP; FDR ). Gene expression differences were also observed in nitric oxide and reactive oxygen species pathways. Nox2 subunits were downregulated in SHRSP NP v GD6 e.g. p40-phox ( FC -2.2; FDR ), but did not change in WKY. qPCR confirmed significantly increased UA Ip3r gene expression in GD6 SHRSP vs GD6 WKY ( 27.1CT vs 28.3CT p ) and reduced Pla2ga expression in WKY vs SHRSP NP UA ( 23.3CT vs 26.4CT; p ). Conclusion: We show that SHRSP UA have different gene expression profiles in response to pregnancy compared to WKY. These early transcript level changes occur prior to structural or functional changes, suggesting that the strains have pre-existing genetic differences that may ‘prime’ the UA to respond differently due to chronic hypertension in SHRSP rats.

Background: A novel pathway for blood pressure (BP) regulation involving the dicarboxylic acid hexadecanedioate (HEXA) was identified in a study associating BP and mortality outcomes with fasting blood metabolites. The functional role of HEXA on BP elevation and vascular reactivity was confirmed by oral administration of hexadecanedioic acid to WKY rats. This study characterized the metabolic effects of hexadecanedioic acid administration in WKY rats, and assessed hemodynamic changes after modulation of endogenous HEXA levels by perturbing the ω-oxidation pathway in the SHRSP rat. Methods: WKY were treated orally with hexadecanedioic acid (250 mg/kg/day) or vehicle (n=5/group) for 3 weeks. Aorta, heart, brain, adipose, kidney, and liver were harvested and global metabolic profiles analysed by UPLC-MS/MS (Metabolon). The aldehyde dehydrogenase (ALDH) inhibitor disulfiram (25 mg/kg/day) or vehicle were administered to SHRSP rats for 14 days (n=7/group). BP was assessed by tail plethysmography and mesenteric arteries were used to assess vascular function by wire myography. Results: Treatment with hexadecanedioic acid increased HEXA levels in all tissues except brain in WKY rats. Metabolomic analysis identified increased fatty acid (FAs) metabolites (e.g. acylcarnitines) in heart, long-chain FAs and ketone body (β-hydroxybutyric acid) in kidney, and dicarboxylate FAs in adipose tissue from hexadecandioic acid treated rats indicating an impairment of FA β-oxidation and a shift towards ω-oxidation. SHRSP rats showed a significant reduction in BP after treatment with disulfiram (ΔSBP, 20.7±4.6 mmHg; P =2.4x10 -4 ). Mesenteric resistance arteries from disulfiram treated SHRSP demonstrated a shift to the right in the contractile response curve to noradrenaline, indicating reduced vascular sensitivity compared to control vessels. Conclusion: Administration of hexadecanedioic acid in addition to increasing BP impacts several metabolic readouts including changes in FA metabolism. Importantly, we demonstrate that inhibition of the ω-oxidation pathway enzyme, ALDH, results in a significant lowering of BP in the hypertensive SHRSP rat. The ω-oxidation pathway is a target for further research to elucidate mechanisms by which HEXA affects BP.

Aims Cerebral small vessel disease (SVD) causes a fifth of all strokes plus diffuse brain damage leading to cognitive decline, physical disabilities and dementia. The aetiology and pathogenesis of SVD are unknown, but largely attributed to hypertension or microatheroma.

Tamm–Horsfall protein was discovered in 1950 by Igor Tamm and Frank Horsfall,1 using a salt precipitation procedure to isolate a potent inhibitor of viral hemagglutination from urine. Muchmore and Decker,2 in 1985, isolated a glycoprotein (calling it uromodulin) with in vitro immunosuppressive properties from urine of pregnant women. In 1987, Pennica et al3 confirmed by cDNA analysis that uromodulin and Tamm–Horsfall protein were identical proteins. Since the initial discovery and without any clear understanding of the function of uromodulin, it was only in 2002 when Hart et al4 identified causative uromodulin mutations in a subset of families having familial juvenile hyperuricemic nephropathy and medullary cystic kidney disease type 2 that interest in uromodulin biology and function was revived. Interest in uromodulin was further revitalized by genome-wide association studies (GWASs) in 2009/2010 showing an association between common single-nucleotide polymorphisms in the upstream region of the UMOD gene with renal function and hypertension.5–8 In 2013, 2 independent groups undertaking post-GWAS functional dissection of the UMOD loci provided molecular insights into a new pathway for hypertension and sodium homeostasis involving uromodulin and opening an exciting line of investigation that could enhance our understanding of renal tubule physiology, sodium homeostasis, blood pressure (BP) regulation, and potentially lead to novel therapies for hypertension.9,10 Uromodulin is a protein exclusively expressed by epithelial cells of the thick ascending limb of Henle’s loop (TAL; Figure 1). The 640 amino-acid precursor is cotranslationally translocated into the endoplasmic reticulum (ER), extensively glycosylated, glypiated, and glycosylphosphatidylinositol anchored to the apical tubular cell membrane. From here it is released by a specific, but as yet unidentified, serine protease(s). The released protein is excreted in the urine at a rate of 20 to 100 mg/d and represents the most abundant urinary protein in …

The use of recombinant human erythropoietin (rHuEpo) is prohibited by the World Anti-Doping Agency (WADA). Using gene microarray technology, we have previously shown that blood gene expression profiles were significantly altered in response to rHuEpo administration both during- and for at least four weeks post administration. Confounders such as altitude exposure and training have the potential to compromise the molecular signature of rHuEpo doping. Purpose: To differentiate the gene expression profile due to strenuous training at altitude from rHuEpo doping. Method: Four (3 males and 1 female) well-trained athletes were exposed to altitude for periods ranging from 3-5 weeks. At altitude, subjects undertook strenuous training involving in two cases as much as 50 km each day for 18 days. One of the subjects had repeated exposure to altitude. Blood was obtained before, during and after altitude exposure. RNA from blood stabilized in Tempus RNA tubes was hybridized to HumanHT-12v4 Expression Illumina BeadChips and altitude-induced molecular responses were compared to the molecular signature of rHuEpo doping previously identified. Results: Preliminary data are encouraging and reveal significant overlap but also differentiation in responses to altitude and rHuEpo. Conclusion: These results provide further support for the use of blood gene biomarkers to improve the performance of current anti-doping methods such as the Athlete Biological Passport for rHuEpo detection.

A recent genome-wide association study identified a locus on chromosome 16 in the promoter region of the uromodulin ( UMOD ) gene that is associated with hypertension. Here, we examined the hypertension signal with functional studies in Umod knockout (KO) mice. Systolic blood pressure was significantly lower in KO versus wild-type (WT) mice under basal conditions (KO: 116.6±0.3 mm Hg versus WT: 136.2±0.4 mm Hg; P P P + excretion and further Na + loss. The difference in sodium uptake that exists between WT and KO strains was explored at the molecular level. Urinary tumor necrosis factor-α levels were significantly higher in KO mice compared with WT mice ( P P P

Fibrosis pathophysiology is critically regulated by Smad 2– and Smad 3–mediated transforming growth factor-β (TGF-β) signaling. Disintegrin metalloproteases (Adam) can manipulate the signaling environment, however, the role and regulation of ADAMs in renal fibrosis remain unclear. TGF-β stimulation of renal cells results in a significant up-regulation of Adams 10, 17, 12, and 19. The selective Smad2/3 inhibitor SB 525334 reversed these TGF-β–induced changes. In vivo, using ureteral obstruction to model renal fibrosis, we observed increased Adams gene expression that was blocked by oral administration of SB 525334. Similar increases in Adam gene expression also occurred in preclinical models of hypertension-induced renal damage and glomerulonephritis. miRNAs are a recently discovered second level of regulation of gene expression. Analysis of 3′ untranslated regions of Adam12 and Adam19 mRNAs showed multiple binding sites for miR-29a, miR-29b, and miR-29c. We show that miR-29 family expression is decreased after unilateral ureter obstruction and this significant decrease in miR-29 family expression was observed consistently in preclinical models of renal dysfunction and correlated with an increase in Adam12 and Adam19 expression. Exogenous overexpression of the miR-29 family blocked TGF-β–mediated up-regulation of Adam12 and Adam19 gene expression. This study shows that Adams are involved in renal fibrosis and are regulated by canonical TGF-β signaling and miR-29. Therefore, both Adams and the miR-29 family represent therapeutic targets for renal fibrosis.

Summary Large numbers of inbred laboratory rat strains have been developed for a range of complex disease phenotypes. To gain insights into the evolutionary pressures underlying selection for these phenotypes, we sequenced the genomes of 27 rat strains, including 11 models of hypertension, diabetes, and insulin resistance, along with their respective control strains. Altogether, we identified more than 13 million single-nucleotide variants, indels, and structural variants across these rat strains. Analysis of strain-specific selective sweeps and gene clusters implicated genes and pathways involved in cation transport, angiotensin production, and regulators of oxidative stress in the development of cardiovascular disease phenotypes in rats. Many of the rat loci that we identified overlap with previously mapped loci for related traits in humans, indicating the presence of shared pathways underlying these phenotypes in rats and humans. These data represent a step change in resources available for evolutionary analysis of complex traits in disease models. PaperClip, Graphical Abstract, Highlights • Genomes of 27 rat strains were sequenced; >13 million sequence variants identified • Selective sweeps and coevolved gene clusters were detected in 11 disease models • Previously identified and new disease genes and pathways were identified • This is first evolutionary analysis of artificial selection for disease phenotypes, Evolution analysis of artificial selection for disease phenotypes, such as hypertension and diabetes, in 27 rat strains reveals disease-related variants and loci.

Functional genomics requires an understanding of the complete network of changes within an organism by extensive measurements of moieties from mRNA, proteins, and metabolites. Metabolomics utilizes analytic chemistry tools to profile the complete spectrum of metabolites found in a tissue, cells, or biofluids using a wide range of tools from infrared spectroscopy, fluorescence spectroscopy, NMR spectroscopy, and mass spectrometry. In this protocol, we outline a procedure for performing metabolomic analysis of urine samples using liquid chromatography-mass spectrometry (LC-MS). We outline the advantages of using this approach and summarize some of the early promising studies in cardiovascular diseases using this approach.

Please cite this paper as: Mackenzie RM, Sandrim VC, Carty DM, McClure JD, Freeman DJ, Dominiczak AF, McBride MW, Delles C. Endothelial FOS expression and pre-eclampsia. BJOG 2012;119:1564–1571. Objective To study gene expression profiles in human endothelial cells incubated with plasma from women who developed pre-eclampsia and women with normotensive pregnancies. Design A case–control study. Setting A longitudinal nested case–control study within three maternity units. Population A mixed obstetric population attending maternity hospitals in Glasgow. Methods Plasma was obtained at both 16 and 28 weeks of gestation from 12 women: six women subsequently developed pre-eclampsia (cases) and six women, matched for age, body mass index (BMI) and parity, remained normotensive (controls). Human umbilical vein endothelial cells (HUVECs) were incubated with plasma for 24 hour before RNA isolation. Main outcome measures Gene expression profiles were compared between the two gestational time points using Illumina® HumanHT-12 v4 Expression BeadChips. Differential mRNA expression observed in microarray experiments were validated using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), and gene networks were analysed using Ingenuity® pathway analysis. Results There was a significant difference in the expression of 25 genes following incubation with plasma from controls, and an increase in the expression of 11 genes following incubation with plasma from cases, with no overlap between the two groups (false discovery rate, FDR

Astrocytes undergo major phenotypic changes in response to injury and disease that directly influence repair in the CNS, but the mechanisms involved are poorly understood. Previously, we have shown that neurosphere-derived rat astrocytes plated on poly-l-lysine (PLL-astrocytes) support myelination in dissociated rat spinal cord cultures (myelinating cultures). It is hypothesized that astrocyte reactivity can affect myelination, so we have exploited this culture system to ascertain how two distinct astrocyte phenotypes influence myelination. Astrocytes plated on tenascin C (TnC-astrocytes), a method to induce quiescence, resulted in less myelinated fibers in the myelinating cultures when compared with PLL-astrocytes. In contrast, treatment of myelinating cultures plated on PLL-astrocytes with ciliary neurotrophic factor (CNTF), a cytokine known to induce an activated astrocyte phenotype, promoted myelination. CNTF could also reverse the effect of quiescent astrocytes on myelination. A combination of microarray gene expression analysis and quantitative real-time PCR identified CXCL10 as a potential candidate for the reduction in myelination in cultures on TnC-astrocytes. The effect of TnC-astrocytes on myelination was eliminated by neutralizing CXCL10 antibodies. Conversely, CXCL10 protein inhibited myelination on PLL-astrocytes. Furthermore, CXCL10 treatment of purified oligodendrocyte precursor cells did not affect proliferation, differentiation, or process extension compared with untreated controls, suggesting a role in glial/axonal ensheathment. These data demonstrate a direct correlation of astrocyte phenotypes with their ability to support myelination. This observation has important implications with respect to the development of therapeutic strategies to promote CNS remyelination in demyelinating diseases.

Background Our previous studies demonstrated reduced rat glutathione S-transferase m type 1 (Gstm1) expression in stroke-prone spontaneously hypertensive rats (SHRSPs), when compared with the normotensive Wistar-Kyoto rat. Methods This study investigated the effects of angiotensin II type 1 receptor blocker (ARB) and a diuretic/vasodilator combination on the expression levels of rat Gstm1 and other Gstm isoforms. Results Antihypertensive treatments of young and mature SHRSPs with an ARB and a diuretic/vasodilator combination improved SBP but did not affect the expression levels of Gstm1. Although Gstm1 is a member of a family of highly homologous genes, with the exception of Gstm2, there was no evidence for compensatory increase in expression of other Gstm isoforms. In contrast, we observed reduced expression of several other Gstm isoforms in untreated SHRSPs. Untreated SHRSPs demonstrated increased renal and vascular oxidative stress, both of which were not significantly affected by the antihypertensive treatments. Untreated SHRSPs scored significantly higher when assessed for renal histopathological damage, and this was improved by antihypertensive treatments. Conclusion These results suggest that reduced Gstm1 expression in SHRSPs is due to strain-dependent genetic abnormalities, playing a causative role in the development of hypertension, probably through oxidative stress pathway. Renal changes occur as a consequence of increased blood pressure and can be improved when treated with antihypertensive drugs. In silico comparative genome analysis combined with expression studies in rat and human vascular tissue revealed that there are possible four human homologues (GSTM1, GSTM2, GSTM4 and GSTM5) for rat Gstm1.

Angiotensin-converting enzyme (ACE) 2 is a recently identified homologue of ACE. There is great interest in the therapeutic benefit for ACE2 overexpression in the heart. However, the role of ACE2 in the regulation of cardiac structure and function, as well as maintenance of systemic blood pressure, remains poorly understood. In cell culture, ACE2 overexpression led to markedly increased myocyte volume, assessed in primary rabbit myocytes. To assess ACE2 function in vivo, we used a recombinant adeno-associated virus 6 delivery system to provide 11-week overexpression of ACE2 in the myocardium of stroke-prone spontaneously hypertensive rats. ACE2, as well as the ACE inhibitor enalapril, significantly reduced systolic blood pressure. However, in the heart, ACE2 overexpression resulted in cardiac fibrosis, as assessed by histological analysis with concomitant deficits in ejection fraction and fractional shortening measured by echocardiography. Furthermore, global gene expression profiling demonstrated the activation of profibrotic pathways in the heart mediated by ACE2 gene delivery. This study demonstrates that sustained overexpression of ACE2 in the heart in vivo leads to the onset of severe fibrosis.

Major advances have been made in the understanding of the genetic basis of diseases since Mendel's publication of the results of plant breeding experiments in 1866. To date these advances have been largely confined to the monogenic disorders — caused by mutations in a single gene. The public-health implications of these advances is relatively limited. In this review we explore our current understanding of the genetic basis of human traits and the reasons why current theories may account for the difficulties in identifying the genes for common diseases. We then postulate that semantic computing may be rightly poised to help understand complex disease causation, and explore the efforts that have been made to date to develop the necessary technological approach to the problem.

Recent advances in genotyping technology and insights into disease mechanisms have increased interest in the genetics of cardiovascular disease. Several candidate genes involved in cardiovascular diseases were identified from studies using animal models, and the translation of these findings to human disease is an exciting challenge. There is a trend towards large-scale genome-wide association studies that are subject to strict quality criteria with regard to both genotyping and phenotyping. Here, we review some of the strategies that have been developed to translate findings from experimental models to human disease and outline the need for optimizing global approaches to analyze such results. Findings from ongoing studies are interpreted in the context of disease pathways instead of the more traditional focus on single genetic variants.

The existence of blood pressure quantitative trait loci exaggerated by salt on rat chromosome 2 has been confirmed previously using congenic strains derived from stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto (WKY) rats. This study aimed to dissect the implicated chromosome 2 region and to identify candidate genes based on microarray expression profiling and real-time PCR. A marker-assisted breeding strategy generated congenic strains SP.WKYGla2a (D2Rat13-D2Rat157), SP.WKYGla2c* (D2Wox9-D2Mgh12), and SP.WKYGla2k (D2Mit21-D2Rat157) using SHRSP as the recipient and WKY as the donor strain. The SP.WKYGla2k strain contains a 10-cM congenic interval, which is encompassed within the larger (64-cM) SP.WKYGla2a congenic region. Salt-loaded systolic blood pressure, measured by radiotelemetry, was significantly lower in the SP.WKYGla2a and SP.WKYGla2k strains compared with SHRSP. Salt sensitivity in SP.WKYGla2c* was not significantly different from SHRSP. Exclusion mapping identified a 6-Mbp region harboring genes responsible for salt-sensitive blood pressure regulation. Microarray expression profiling was carried out in whole homogenized kidneys from parental and SP.WKYGla2a strains. Examination of expression data within the minimal congenic interval identified the positional candidates Edg1 and Vcam1 , demonstrating significantly elevated renal RNA expression levels in the SHRSP compared with WKY and SP.WKYGla2a congenic strains. These results were confirmed by quantitative real-time PCR. DNA sequencing identified SNPs in both Edg1 and Vcam1 between SHRSP and WKY rats. In conclusion, we have identified a suggestive minimal interval encompassing a 6-Mbp region on rat chromosome 2. This region contains several physiological candidate genes for salt-sensitive hypertension in the SHRSP, including Edg1 and Vcam1 , which are differentially expressed and lie on common and functionally important pathways.

Oxidative stress plays an important role in the pathogenesis of a variety of disorders including cardiovascular disease. Understanding the genetic background of increased oxidative stress will facilitate targeted prevention and therapy of these diseases. Strategies to analyse genomics of oxidative stress include genome scans in rodent models, construction of congenic animals and candidate gene approaches. A new family of candidate genes for human cardiovascular disease, glutathione S-transferases (GSTMs), have been derived from experiments in congenic rats. Knowledge of the physiology of superoxide production led to analysis of genetic variants of the CYBA gene encoding the p22phox unit of NADPH oxidase. Against the background of rapidly evolving genotyping technology we are currently facing challenges in accurate phenotyping and biomarker development to measure oxidative stress, together with the need to develop new statistical paradigms to encompass gene-gene and gene-environment interactions.

Recombinant human erythropoietin (rHuEPO) is frequently abused by athletes as a performance-enhancing drug, despite being prohibited by the World Anti-Doping Agency. Although the methods to detect blood doping, including rHuEPO injections, have improved in recent years, they remain imperfect. In a proof-of-principle study, we identified, replicated, and validated the whole blood transcriptional signature of rHuEPO in endurance-trained Caucasian males at sea level ( n = 18) and Kenyan endurance runners at moderate altitude ( n = 20), all of whom received rHuEPO injections for 4 wk. Transcriptional profiling shows that hundreds of transcripts were altered by rHuEPO in both cohorts. The main regulated expression pattern, observed in all participants, was characterized by a “rebound” effect with a profound upregulation during rHuEPO and a subsequent downregulation up to 4 wk postadministration. The functions of the identified genes were mainly related to the functional and structural properties of the red blood cell. Of the genes identified to be differentially expressed during and post-rHuEPO, we further confirmed a whole blood 34-transcript signature that can distinguish between samples collected pre-, during, and post-rHuEPO administration. By providing biomarkers that can reveal rHuEPO use, our findings represent an advance in the development of new methods for the detection of blood doping.

Supplemental Digital Content is available in the text., Background— Phenotypic switching of vascular smooth muscle cells from a contractile to a synthetic state is implicated in diverse vascular pathologies, including atherogenesis, plaque stabilization, and neointimal hyperplasia. However, very little is known about the role of long noncoding RNA (lncRNA) during this process. Here, we investigated a role for lncRNAs in vascular smooth muscle cell biology and pathology. Methods and Results— Using RNA sequencing, we identified >300 lncRNAs whose expression was altered in human saphenous vein vascular smooth muscle cells following stimulation with interleukin-1α and platelet-derived growth factor. We focused on a novel lncRNA (Ensembl: RP11-94A24.1), which we termed smooth muscle–induced lncRNA enhances replication (SMILR). Following stimulation, SMILR expression was increased in both the nucleus and cytoplasm, and was detected in conditioned media. Furthermore, knockdown of SMILR markedly reduced cell proliferation. Mechanistically, we noted that expression of genes proximal to SMILR was also altered by interleukin-1α/platelet-derived growth factor treatment, and HAS2 expression was reduced by SMILR knockdown. In human samples, we observed increased expression of SMILR in unstable atherosclerotic plaques and detected increased levels in plasma from patients with high plasma C-reactive protein. Conclusions— These results identify SMILR as a driver of vascular smooth muscle cell proliferation and suggest that modulation of SMILR may be a novel therapeutic strategy to reduce vascular pathologies.

Supplemental Digital Content is available in the text, Objectives: Preeclampsia is a multisystem disease that significantly contributes to maternal and foetal morbidity and mortality. In this study, we used a nonbiased microarray approach to identify novel circulating miRNAs in maternal plasma that may be associated with preeclampsia. Methods: Plasma samples were obtained at 16 and 28 weeks of gestation from 18 women who later developed preeclampsia (cases) and 18 matched women with normotensive pregnancies (controls). We studied miRNA expression profiles in plasma and subsequently confirmed miRNA and target gene expression in placenta samples. Placental samples were obtained from an independent cohort of 19 women with preeclampsia matched with 19 women with normotensive pregnancies. Results: From the microarray, we identified one miRNA that was significantly differentially expressed between cases and controls at 16 weeks of gestation and six miRNAs that were significantly differentially expressed at 28 weeks. Following qPCR validation, only one miR-206 was found to be significantly increased in 28-week samples in women who later developed preeclampsia (1.4-fold change ± 0.2). The trend for increase in miR-206 expression was mirrored within placental tissue from women with preeclampsia. In parallel, IGF-1, a target gene of miR-206, was also found to be downregulated (0.41 ± 0.04) in placental tissue from women with preeclampsia. miR-206 expression was also detectable in myometrium tissue and trophoblast cell lines. Conclusion: Our pilot study has identified miRNA-206 as a novel factor upregulated in preeclampsia within the maternal circulation and in placental tissue.

Purpose of review: Essential hypertension is a complex polygenetic disease with a major impact on health worldwide. Despite earlier detection of promising candidate genes, only recent advances in genotyping technology and new approaches to examining gene and protein function have provided the tools to unravel the genetic basis of hypertension. Recent findings: In humans, genome-wide scans resulted in the identification of several chromosomal loci that are linked to hypertension. These regions still contain a large number of potential candidate genes, but high-throughput genotyping methods will facilitate the detection and analysis of single-nucleotide polymorphisms within these genes. The focus will be on animal models of hypertension, specifically rats. Congenic strains facilitate the identification of genetic determinants of hypertension, and new technologies such as RNA interference (which silences the expression of target genes) and transgenic rescue models will help us to analyse the relationship between genes and function. Analysis of conserved synteny (preserved order of genes) between species allows translation of findings from rodent models to essential hypertension in humans. Recent discoveries and approaches beyond genomics will also be discussed, including the regulatory role of microRNA and the concept of proteomics. Summary: The genetic basis of hypertension is complex, and the examination of the functional consequences of genetic variants in particular is still challenging. A number of tools are now available with which to examine gene–function relationships, and these will provide an improved understanding of cardiovascular genomics. This will eventually lead to targeted prevention and treatment strategies in patients with hypertension and other cardiovascular diseases.