Hypertension

BACKGROUNDSalt-sensitive hypertension is a prevalent and clinically significant subtype of hypertension, where increased dietary salt intake elevates blood pressure and causes injury to multiple organ systems. Despite extensive research, dynamic molecular changes and conserved versus organ-specific transcriptional programs in hypertensive multi-organ damage remain poorly understood. Defining complex molecular pathways both in a temporal sequence and in an organ-specific manner is essential for developing targeted, precision therapies to mitigate hypertensive disease burden. METHODSWe generated a longitudinal multi-organ transcriptomic atlas of salt-sensitive hypertension using RNA sequencing of kidney cortex, kidney medulla, heart, and liver from Dahl salt-sensitive rats across four disease stages. A comprehensive bioinformatic analysis mapped dynamic transcriptional programs, evaluated 50 biological pathways, and defined upstream regulators. Histological and biochemical assays complemented transcriptomic analysis, while integration with human genome-wide association studies (GWAS) and compound-transcriptome analysis provided translational insights and identified candidate therapeutics. RESULTSSalt-induced hypertension elicited both shared and tissue-specific transcriptional programs that evolved with disease progression. The kidney medulla showed robust early immune activation with metabolic suppression, while the cortex exhibited transient metabolic activation before declining and initiating immune activation. The liver and heart showed time-dependent metabolic and inflammatory remodeling. Cross-organ comparisons revealed a shared early proliferative response that converged on proinflammatory and fibrotic signatures. Upstream regulator analysis identified 79 time- and tissue-specific transcription factors associated with gene expression dynamics. GWAS integration analysis revealed endocrine signaling, ion transport, lipid metabolism, and detoxification as conserved pathways across species, underscoring the translational relevance of the model and study. Predictive compound- transcriptome analyses identified kinase inhibitors targeting phosphoinositide 3-kinase, mechanistic target of rapamycin and cyclin-dependent kinases as top candidates to counteract maladaptive transcriptional programs. CONCLUSIONSThis study defines temporal and tissue-specific transcriptomic remodeling in salt-sensitive hypertension and highlights the need for precision interventions to prevent progressive organ damage.

Structured Abstract BackgroundPrimary aldosteronism is the most common form of secondary arterial hypertension, due to autonomous aldosterone production from the adrenal cortex. Genome wide association studies discovered genetic risk loci associated with the disease, which may affect adrenal cortex renewal, differentiation and lineage conversion. Genetic susceptibility may be modulated by environmental challenges. MethodHere we investigate how environmental cues affecting mineralocorticoid output modulate adrenal cortex homeostasis, cell lineage conversion and zone-specific transcriptional landscape. We have used a newly developed Cyp11b2Cremouse model and characterised its adaptation to a high or low salt diet (HSD, LSD), as well as dexamethasone (DEX) treatment. To explore underlying mechanisms, deep functional and morphological phenotyping, lineage tracing and spatial transcriptomics of the adrenal cortex were performed. ResultsCyp11b2 expression was detected in Cyp11b2Cre-mTmG mice as early as day P1 in different areas of the ZG, associated with high plasma aldosterone levels, with lineage conversion of zona glomerulosa (ZG) into zona fasciculata (ZF) cells progressing between 2 and 9 weeks of age and a progressive reduction of ZG size and evolution of cell components of the adrenal cortex over time. Transdifferentiation progressed into the X-zone (ZX) in females, revealing a previously unrecognized connection between ZF and ZX cells in adult mice. A sexually dimorphic, reciprocal interaction between the ZG and the ZF in adapting to salt diets or DEX treatment was observed, involving changes in cell composition and transcriptional reprogramming of the three zones. ConclusionHSD, LSD and DEX induce a sexually dimorphic cellular and transcriptional response, involving all layers of the adrenal cortex, and the reciprocal contribution of ZG and ZF cells, indicating functional interaction between adrenocortical zones in adapting to external cues.

BackgroundAldosterone overactivity intensifies central sodium sensitivity and sympathetic output, driving salt-sensitive hypertension, but specific mechanisms remain incompletely defined. Herein, we aimed to explore the role of organum vasculosum of the lamina terminalis glutamatergic neurons (OVLTGlut) and their hyperexcitability mechanisms in hyperaldosteronism-associated hypertension. MethodsAdult age matched male TASK-/- mice (primary aldosteronism model) and wild-type controls (TASK+/+) mice were used. Neuronal excitability was assessed via patch-clamp techniques. Arterial blood pressure (BP) monitored via telemetry or carotid catheterization. Chronic drug delivery used minipumps. RNA-seq/qPCR profiled gene expression, and intracerebroventricular hypertonic saline tested sodium sensitivity. ResultsIn TASK-/- mice, heightened OVLTGlut activity increased sympathetic outflow and hypertension, mitigated by OVLTGlut neuron ablation. Optogenetic activation of these neurons or their paraventricular nucleus (PVN) / rostral ventrolateral medulla (RVLM) projections acutely elevated BP, with ablation reducing BP selectively in TASK-/- mice. Aldosterone dependence of OVLTGlut-PVN/RVLM neuron hyperactivity was evident in both TASK-/- mice and TASK+/+ mice with chronic aldosterone infusion. Aldosterone chronic infusion enhanced central sodium pressor effects, that were nullified by OVLTGlut-PVN/RVLM neuron lesioning. RNA-seq indicated that aldosterone-induced ion channel expression spectrum changes, including potassium channels and the epithelial sodium channel, underlie the neuronal hyperexcitability. ConclusionOveractivation of OVLTGlut neurons contributes to hypertension in TASK-/- mice through regulation of OVLTGlut-PVN/RVLM circuits. The hyperexcitability of these neurons, possibly due to aldosterone-induced changes in ion channel expression spectrum, contribute to hypertension by amplifying central sodium sensitivity.

BackgroundHypertension is a major risk factor for cardiovascular and renal diseases, significantly contributing to morbidity and mortality. The COVID-19 pandemic has heightened concerns about the impact of hypertension on severe COVID-19 outcomes. MethodsWe conducted a cross-sectional analysis using the 2021 MarketScan Commercial and Health and Productivity Management databases. The study included adults aged 18-64 with continuous employer-sponsored private insurance, excluding those with pregnancy or capitated plans. We compared excess total medical costs, healthcare utilization (including the number of emergency department visits, inpatient admissions, outpatient visits, and outpatient prescription drugs), and productivity losses and related costs due to sick absences, short-term disability (STD), and long-term disability (LTD) between individuals with and without hypertension, further stratified by COVID-19 diagnosis. Multivariate regression models adjusted for demographics and comorbidities were used to estimate the differences in outcomes. ResultsAmong 1,612,398 adults aged 18-64 years, 13% had hypertension in 2021. Those with hypertension were older, were less likely to be female or live in urban areas, and exhibited a higher prevalence of comorbidities. The total excess medical costs associated with hypertension were $8723 per patient (95% CI, $8352-$9093), which was significantly higher by $6117 (95% CI, $4780-$7453) among individuals diagnosed with COVID-19. Persons with hypertension had higher health care utilization, including a higher number of ED visits (0.21 per patient; 95% CI, 0.21-0.22), inpatient admissions (0.11; 95% CI, 0.10-0.12), outpatient visits (5.42; 95% CI, 5.36-5.49), and outpatient prescription drugs (10.85; 95% CI, 10.75-10.94). Moreover, they experienced a greater number of sick absences (1.22 days; 95% CI, 1.07-1.36) and STD occurrences (3.68 days; 95% CI, 3.38-3.98) per patient compared to those without hypertension. These trends were further exacerbated among individuals diagnosed with COVID-19. ConclusionsHypertension markedly increases medical costs, healthcare utilization, and productivity losses, which are further exacerbated by COVID-19. These findings highlight the substantial economic burden of managing hypertension in the context of the COVID-19 pandemic and underscore the importance of targeted interventions.

BackgroundAortic stiffening is a consequence of hypertension and a major contributor to end organ damage. A key driver of aortic stiffening is fibrosis involving the excess production of extracellular matrix (ECM) proteins such as collagen, fibronectin and laminin. The present study aimed to identify the cell types and signalling mechanisms that contribute to aortic fibrosis in hypertension. Methods and ResultsMale C57BL/6 mice (10-12-week-old) were randomly assigned to a 28-day angiotensin II (0.7 mg/kg/day) or vehicle (saline) infusion via osmotic minipump (s.c.). At endpoint, scRNA-seq analysis of 26,196 cells recovered all major aortic cell populations. Among these, fibroblasts exhibited the greatest heterogeneity and shift in gene expression after angiotensin II compared to all other cell types. Gene ontology analyses revealed that after angiotensin II treatment, a particular subcluster of fibroblasts (Fibro-Cthrc1) - characterised by its high expression of Cthrc1 - was especially fibrogenic. Fibro-Cthrc1 cells were nearly undetectable in aortas from vehicle-infused mice. Transcripts relating to ECM remodelling (Thbs2, Cdh11 and Postn) and collagen production (specifically collagen type I, III and V) were more highly enriched in Fibro-Cthrc1 compared to other fibroblasts within hypertensive aortas. Moreover, GO terms corresponding to profibrotic signalling pathways (i.e., cell adhesion, extracellular matrix organisation and collagen fibril organisation) were significantly enriched in Fibro-Cthrc1. Spatial transcriptomics and immunohistochemistry confirmed the presence of Fibro-Cthrc1 in the adventitial layer of angiotensin II-infused but not vehicle-infused mice. Finally, analysis of plasma analytes in approximately 24,000 participants of the UK Biobank collection revealed CTHRC1 to be strongly associated with raised systolic blood pressure and pulse pressure, and a strong predictor of the risk of developing hypertension over a 15-year follow-up. ConclusionOur study identifies a novel fibroblast subcluster, Fibro-Cthrc1, as a potential driver of aortic fibrosis and stiffening in hypertension. This cluster is absent in normotensive aortas, suggesting that targeting Fibro-Cthrc1 therapeutically could prevent aortic fibrosis and its associated hypertensive end-organ damage. Notably, such an approach may avoid compromising physiological extracellular matrix production and vessel integrity. Translational perspectiveAortic stiffening is a hallmark of hypertension resulting from functional (vasoconstriction) and structural (extracellular matrix remodelling) alterations of the vessel wall. While several antihypertensive medications address functional changes, no therapies directly target the causes of the structural remodelling. The therapeutic challenge is to distinguish between physiological and pathological extracellular matrix remodelling. This study identifies a novel highly profibrotic fibroblast cell population (Fibro-Cthrc1) present in aortas from hypertensive, but not normotensive mice. This raises the possibility that Fibro-Cthrc1 may be a key driver of aortic stiffening and a promising future therapeutic target.

Blood pressure variability (BPV) has emerged as a significant risk factor for cognitive decline and dementia, independent of alterations in average blood pressure (BP). However, the impact of large BP fluctuations on neurovascular function remains poorly understood. In this study, we developed a novel murine model of BPV in middle-aged mice using intermittent Angiotensin II infusions. Radio telemetry confirmed that 24-hr BP averages in BPV mice remained comparable to controls, demonstrating BPV in the absence of hypertension. Chronic (20-25 days) BPV resulted in a blunted bradycardic response and cognitive deficits. Two-photon imaging revealed heightened pressure-evoked constrictions (myogenic response) in parenchymal arterioles of BPV mice. While sensory stimulus-evoked dilations (neurovascular coupling) were amplified at higher BP levels in control mice, this pressure-dependent effect was abolished in BPV mice. Our findings indicate that chronic BP fluctuations impair vascular function within the neurovascular complex and contribute to cognitive decline, emphasizing BPV as a critical factor in brain health.

BackgroundHyperactivity of the orexin system has been implicated in hypertension, yet the long-term impact of orexin 1 receptor (OX1R) overexpression in the paraventricular nucleus (PVN), a key brain region involved in arterial blood pressure (ABP) regulation, remains unclear. This study examined whether chronic OX1R overexpression in the PVN alters cardiovascular, neuroendocrine, and oxidative functions. MethodsAdult male Sprague-Dawley rats received bilateral PVN injections of AAV2-OX1R or control virus AAV2-GFP. Their ABP and heart rate (HR) were monitored for eight weeks via radiotelemetry. Renal sympathetic nerve activity (RSNA) and ABP responses to PVN orexin A administration were assessed using in vivo recordings. Reactive oxygen species (ROS) were quantified using MitoProbe, and gene expression was analyzed by qPCR. Primary neuronal cultures were used to explore underlying mechanism involved in increased ROS production and neuronal activity. ResultsPVN OX1R overexpression increased mean ABP ([~]10 mmHg), water intake, and ROS levels in both the PVN and peripheral organs. In addition, orexin A evoked exaggerated RSNA (155% vs. 73%) and pressor responses (27 vs. 16 mmHg) in PVN OX1R overexpression rats compared to control rats, these effects were attenuated by the OX1R antagonist SB408124. Plasma vasopressin levels were elevated, and brain sections confirmed increased ROS in OX1R-positive neurons. In vitro experiments further demonstrated that orexin A upregulated ROS-generating enzymes, suppressed antioxidant genes, and enhanced neuronal excitability. ConclusionChronic PVN OX1R overexpression induces oxidative stress, sympathetic overactivity, and increased plasma vasopressin, contributing to hypertension development. Targeting PVN OX1R signaling may provide therapeutic benefit for hypertension.

BACKGROUNDSalt sensitivity of blood pressure (SSBP) is an independent risk factor for cardiovascular morbidity and mortality, yet the etiology is poorly understood. We previously found that serum/glucocorticoid-regulated kinase 1 (SGK1) and epoxyeicosatrienoic acids (EETs) regulate epithelial sodium channel (ENaC)-dependent sodium entry into monocyte-derived antigen-presenting cells (APCs) and activation of NADPH oxidase, leading to the formation of isolevuglandins (IsoLGs) in SSBP. Whereas aldosterone via the mineralocorticoid receptor (MR) activates SGK1 leading to hypertension, our past findings indicate that levels of plasma aldosterone do not correlate with SSBP, and there is little to no MR expression in APCs. Thus, we hypothesized that cortisol acting via the glucocorticoid receptor (GR), not the MR in APCs mediates SGK1 actions to induce SSBP. METHODSWe performed cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq) analysis on peripheral blood mononuclear cells of humans rigorously phenotyped for SSBP using an inpatient salt loading/depletion protocol to determine expression of MR, GR, and SGK1 in immune cells. In additional experiments, we performed bulk transcriptomic analysis on isolated human monocytes following in vitro treatment with high salt from a separate cohort. We then measured urine and plasma cortisol, cortisone, renin, and aldosterone. Subsequently, we measured the association of these hormones with changes in systolic, diastolic, mean arterial pressure and pulse pressure as well as immune cell activation via IsoLG formation. RESULTSWe found that myeloid APCs predominantly express the GR and SGK1 with no expression of the MR. Expression of the GR in APCs increased after salt loading and decreased with salt depletion in salt-sensitive but not salt-resistant people and was associated with increased expression of SGK1. Moreover, we found that plasma and urine cortisol/cortisone but not aldosterone/renin correlated with SSBP and APCs activation via IsoLGs. We also found that cortisol negatively correlates with EETs. CONCLUSIONOur findings suggest that renal cortisol signaling via the GR but not the MR in APCs contributes to SSBP via cortisol. Urine and plasma cortisol may provide an important currently unavailable feasible diagnostic tool for SSBP. Moreover, cortisol-GR-SGK1-ENaC signaling pathway may provide treatment options for SSBP. Novelty and RelevanceO_ST_ABSWhat Is New?C_ST_ABSO_LIAlthough salt sensitivity is a major risk factor for cardiovascular morbidity and mortality, the mechanisms underlying the salt sensitivity of blood pressure (SSBP) are poorly understood. C_LIO_LIHigh salt modifies glucocorticoid-receptor expression in antigen-presenting cells (APCs), suggesting a critical role of glucocorticoids in SSBP. C_LIO_LIElevated glucocorticoid receptor (GR) expression compared to mineralocorticoid receptor (MR) expression in APCs provides evidence for a GR-dependent pathway to SSBP. Isolevuglandins (IsoLGs) increased in APCs in vitro after hydrocortisone treatment compared to aldosterone treatment, indicating that cortisol was the predominant driver of IsoLG production in these cells. C_LIO_LIOur studies suggest a mechanism for SGK1 expression through GR activation by cortisol that differs from the currently accepted mechanism for SSBP pathogenesis. C_LI What Is Relevant?O_LIAlthough aldosterone has been used to study SSBP, there has been no consideration of cortisol as a major driver of the condition. C_LIO_LIUnderstanding alternative inflammatory pathways that affect SSBP may provide insights into the mechanism of SSBP and suggest a range of therapeutic targets. C_LIO_LIOur studies may provide a practical approach to understanding and treating salt-sensitive hypertension. C_LI Clinical/Pathophysiological Implications?O_LIOur findings firmly support a GR-dependent signaling pathway for activating SSBP via SGK1 expression. A cortisol-driven mechanism could provide a practical approach for targeted treatments for salt-sensitive hypertension. Moreover, it could pave the way for a diagnostic approach. C_LI

BackgroundPerivascular spaces (PVS) are fluid-filled spaces that functions as channels for glymphatic clearance in the brain. Enlarged perivascular spaces (ePVS) have been associated with high blood pressure. Hypertension features abnormal increases in muscle sympathetic nerve activity (MSNA), which constricts blood vessels in the muscle vascular bed, but the underlying mechanisms for this increase are not understood. Moreover, the association between ePVS and the resting sympathetic outflow from the brain has not been studied in normotensive or hypertensive humans. Therefore, we assessed whether ePVS is associated with muscle sympathetic nerve activity (MSNA) in 25 hypertensive patients and 50 healthy normotensive adults. MethodsT1-weighted MRI anatomical brain images were analysed for ePVS using a deep learning-based segmentation algorithm - nnU-Net. ePVS in the white matter (WM), basal ganglia (BG), hippocampus (HP), and midbrain (MB) were analysed. Spontaneous bursts of MSNA were recorded from the right common peroneal nerve via a tungsten microelectrode immediately before the MRI scan. ResultsSignificant associations were found between ePVS and MSNA in the WM, BG, and HP in both the normotensive and hypertensive groups after adjusting for confounding factors (age, sex, mean blood pressure, total intracranial volume). However, the association between MSNA and MB ePVS was only observed in the hypertensive group. ConclusionThis finding provides insights into the pathophysiology of elevated sympathetic drive in hypertension. What is new?* Enlarged perivascular spaces (ePVS) are associated with muscle sympathetic nerve activity (MSNA) in normotensive and hypertensive humans. * Hypertensives and normotensives display differences in the association between the midbrain ePVS and MSNA. What are the clinical implications?* Insights into the centrally driven pathophysiological mechanism of elevated sympathetic nerve outflow in hypertension has been revealed. * ePVS may be used as an imaging biomarker for individuals with high sympathetic nerve activity, allowing identification of risk individuals that require microneurographic assessment of sympathetic nerve activity

BackgroundPreeclampsia is a hypertensive disorder of pregnancy associated with systemic endothelial dysfunction and, in severe cases, maternal neurological complications. Placenta-derived exosomal microRNAs (exomiRs) mediate inter-organ communication and may contribute to neurovascular injury, but their role in maternal brain dysregulation remains unclear. MethodsWe performed systems-level bioinformatic analyses of 12 differentially expressed exomiRs (6 from early-onset and 6 from late-onset preeclampsia) to assess their potential impact on brain homeostasis. Target interactomes were examined for functional enrichment, subcellular localization, and network complexity. ExomiR targets were integrated with cerebrospinal fluid (CSF) proteomic profiles from preeclamptic women with neurological symptoms. We further evaluated regulation of blood-brain barrier (BBB) components and mapped spatial expression of target proteins across brain regions and cell types relevant to neurovascular function. ResultsEarly-and late-onset preeclampsia exomiRs displayed distinct interactomes and biological signatures. Early-onset exomiRs were linked to RNA metabolism, oxidative stress, and endothelial stability, whereas late-onset exomiRs were enriched in nitrogen metabolism and vesicle-mediated transport. Integration with CSF proteomics revealed convergence on dysregulated proteins, including MAPK8, RTN4, and YWHA family members, involved in inflammation, neurodegeneration, and axonal inhibition. Several exomiRs targeted BBB-related proteins (CLDN2, TJP1, EFNA5), suggesting coordinated barrier disruption. Spatial mapping localized these targets to endothelial cells, astrocytes, interneurons, and pyramidal neurons, implicating altered synaptic and glial regulation. ConclusionsPreeclampsia-associated exomiRs may impair maternal brain homeostasis through coordinated regulation of neurovascular, inflammatory, and synaptic pathways. These findings identify candidate molecular mediators of preeclampsia-related neurovascular dysfunction and potential biomarkers for maternal brain injury.

IntroductionCOVID-19 disproportionately affects those with comorbidities and the elderly. Hypertension is the most common pre-existing condition amongst COVID-19 patients. Upregulation of the renin-angiotensin-aldosterone system (RAAS) is common in hypertensive patients and may promote inflammation and ensuing cytokine storm in COVID-19. It is unknown whether RAAS inhibition with ACE1 inhibitors or angiotensin-receptor blockers (ARB) can be harmful or beneficial. MethodsWithin Hackensack Meridian Health network, the largest healthcare provider in New Jersey, we performed a retrospective, multicenter, convenience sampling study of hospitalized COVID-19 patients. Demographics, clinical characteristics, treatments, and outcomes were manually abstracted. Fishers exact tests, and logistic regression were performed. ResultsAmong 3017 hospitalized COVID-19 patients, 1584 (52.5%) carried a diagnosis of hypertension. In the discharged or deceased cohort, the overall mortality was significantly increased at 35% vs 13% among COVID-19 patients with hypertension. However, when adjusted for age, the effect of hypertension on mortality was greatly diminished, with a reduction in odds-ratio by over half; and completely disappeared when adjusted for other major covariates. The mortality rates were lower for hypertensive patients prescribed ACE1 (27%, p=0.001) or ARBs (33%, p=0.12) compared to other anti-hypertensive agents (39%) in the unadjusted analyses. RAAS inhibitor therapy appeared protective compared to other anti-hypertensive agents (p=0.001). ConclusionsWhile our results are limited by the retrospective nature of our study and by potential confounders, our data argue against a harmful effect of RAAS inhibition and support the HFSA/AHA/ACC joint statement recommending continuing ACE1 and ARB therapy in hypertensive COVID-19 patients.

BackgroundEssential hypertension, characterized by vascular dysfunction, remains a leading modifiable cause of death globally. Perivascular adipose tissue (PVAT), which normally reduces vasoconstriction, becomes less anticontractile in hypertension due at least in part to increased reactive oxygen species (ROS). Brown PVAT has emerged as a protective regulator of vascular tone. Follistatin, an activin antagonist, induces browning of peripheral adipose tissue depots via AMPK. We recently reported improved blood pressure, vascular function and reduced vascular ROS by follistatin in the spontaneously hypertensive rat (SHR) model of essential hypertension. Here, we investigate whether follistatin reduces ROS and induces browning in SHR PVAT to restore PVAT function. MethodsSHR were treated with vehicle, follistatin or hydralazine for 8 weeks. Mesenteric white and thoracic brown PVAT from SHR and normotensive Wistar-Kyoto were utilized, with wire myography used to assess vascular function. Nitric oxide (NO) and nitrite were measured in PVAT using DAF-2 FM fluorescence or Griess reagent, respectively. PVAT ROS and browning markers were assessed biochemically and via immunohistochemistry. PVAT was treated ex vivo for 3 days to assess mechanisms of browning. Unbiased proteomic analysis of PVAT was performed using liquid chromatography-mass spectrometry. ResultsSHR PVAT dysfunction, manifest as a pro-contractile effect, was inhibited by follistatin through reducing ROS, enhancing NO bioavailability and inducing browning. Activin neutralization and AMPK phosphorylation mediated the beneficial effect of follistatin on SHR PVAT. Hydralazine-induced blood pressure reduction did not replicate follistatin effects, suggesting vascular benefits of follistatin are mediated by direct PVAT modulation. Proteomic analysis showed that follistatin shifts PVAT proteome towards normal state, upregulating processes associated with adipose tissue browning. ConclusionFollistatin restores PVAT-mediated vascular relaxation via ROS reduction, activin neutralization and AMPK-dependent browning, positioning the potential for PVAT as a therapeutic target for vascular dysfunction in essential hypertension.

Hypertension is a hallmark of cardiovascular abnormalities associated with Williams syndrome (WS), a rare genetic disorder involving microdeletion of genes on human chromosome 7, including the elastin gene (ELN). Heterozygous deletion of Eln (Eln+/-) in mice recapitulates hypertension and arteriopathy associated with WS. Previously, differences in blood pressure elevation and sensitivity to dietary sodium were found to be less profound in female Eln+/- mice. Here, we determined whether ovarian hormones play a role in sex-related difference in blood pressure elevation resulting from Eln haploinsufficiency. Female Eln+/+ and Eln+/- mice instrumented with radiotelemetry devices were subjected to sham surgery or ovariectomy (OVX). We found that OVX lowered diastolic but not systolic blood pressure (SBP) in Eln+/- mice, resulting in increased pulse pressure. In Eln+/- mice, diuresis induced by acute volume expansion was blunted, while anti-natriuresis was exaggerated. Furthermore, amiloride lowered SBP and increased urinary Na+ excretion, suggesting that Eln+/--induced hypertension may be Na+-dependent. We conclude that increased Na+ and water retention by the kidney contribute to hypertension resulting from Eln haploinsufficiency. The underlying mechanism involves the alteration of ovarian hormone effects in the kidney and sustained signaling downstream of the V2 receptor, leading to increased ENaC activity and water reabsorption. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=103 SRC="FIGDIR/small/689164v1_ufig1.gif" ALT="Figure 1"> View larger version (15K): org.highwire.dtl.DTLVardef@1ccfa15org.highwire.dtl.DTLVardef@369344org.highwire.dtl.DTLVardef@fe8194org.highwire.dtl.DTLVardef@ed285d_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical AbstractC_FLOATNO CDPC, cortical duct principal cell; ER, estrogen receptor; PR, progesterone receptor; ENaC, epithelial sodium channel; AQP2, aquaporin 2; V2R, vasopressin V2 receptor; ELN, elastin; PKA, protein kinase A; AC, adenylyl cyclase; Gs, stimulatory G protein; ATP, Adenosine triphosphate; cAMP, cyclic AMP; {oplus}, activating; {ominus}, inhibiting C_FIG

BackgroundHypertension (HTN) is a major global contributor to cardiovascular morbidity and mortality, and improved biomarkers are needed to better characterize individual risk, disease progression, and treatment response. Uromodulin (UMOD), the most abundant protein in human urine reflects tubular health and renal sodium handling. Genome-wide association studies (GWAS) have identified common UMOD promoter polymorphisms associated with HTN across diverse populations, sparking interest in UMOD as both a protein and genetic biomarker. We conducted a systematic review and meta-analysis to evaluate the diagnostic, prognostic, and predictive value of UMOD in HTN. MethodsWe conducted a systematic review and meta-analysis using PubMed and Embase. We included human and animal studies that evaluated UMOD protein level or UMOD-related GWAS outcomes in relation to HTN or HTN-related outcomes. Risk of bias was assessed using the Newcastle-Ottawa Scale. Inverse variance weighed random-effects models were used to analyze continuous outcomes. Publication bias was evaluated using Begg and Egger tests and funnel plots. ResultsForty studies met the inclusion criteria. Across diagnostic, prognostic, and predictive biomarker studies, 10,726 individuals with HTN and 8,762 normotensive (NTN) participants were included. Furthermore, there were 3,461 women with HTN and 3,605 NTN. GWAS studies included >450,000 HTN and >150,000 NTN individuals. Despite supportive findings from in vivo models, across diagnostic, prognostic, predictive, and GWAS qualitative and quantitative analyses, UMOD did not demonstrate clinically meaningful utility as a biomarker for HTN or HTN-related outcomes. ConclusionDespite strong biological plausibility linking UMOD to renal sodium handling and blood pressure regulation, our meta-analysis demonstrates that UMOD is not a clinically useful protein or genetic biomarker for HTN or HTN-related outcomes.

BackgroundThe thiazide-sensitive sodium chloride cotransporter (NCC) is the major apical sodium transporter located in the mammalian renal distal convoluted tubule (DCT). The amount of sodium reabsorbed in the DCT through NCC plays an important role in the regulation of extracellular fluid volume and blood pressure. Dopamine and its receptors constitute a renal antihypertensive system in mammals. The disruption of Drd4 in mice causes kidney-related hypertension. However, the pathogenesis of D4R-deficiency associated hypertension is not well documented. MethodWe assessed the effects of D4R on NCC protein abundances and activities of DCT in mice with renal or global Drd4-deficiencies and expressing human D4.7 variant and in cultured mouse DCT cells, and explored the molecular mechanism. ResultsNCC inhibitor hydrochlorothiazide enhanced the natriuresis in Drd4-/- mice. Renal NCC protein was greater while ubiquitination of NCC was less in Drd4-/- than Drd4+/+ mice. Silencing of D4R in cultured mouse DCT cells increased NCC protein but decreased NCC ubiquitination. D4R agonist had opposite effects that were blocked by the antagonist. In mouse kidneys and DCT cells D4R and NCC colocalized and co-immunoprecipitated. Moreover, D4R-agonist promoted the binding between the two proteins demonstrated by fluorescence resonance energy transfer. D4R agonism internalized NCC, decreased NCC in the plasma membrane, increased NCC in lysosomes and reduced NCC-dependent-intracellular-sodium transport. The lysosomal inhibitor chloroquine prevented the D4R-induced NCC-reduction. A shortened NCC half-life was suggested by its decay under cycloheximide-chase. Ubiquitin-specific-protease 48 (USP48, a deubiquitinating enzyme) was increased in the kidneys and cells with Drd4-deficiency while D4R stimulation decreased it in vitro and reduction of USP48 with siRNA decreased NCC expression. The mice carrying human D4.7 variant or with renal reduction of D4R developed hypertension with increased NCC. ConclusionOur data demonstrates that D4R downregulates NCC by promoting USP48-associated deubiquitination and subsequent internalization, lysosome relocation and degradation.

BackgroundGenetic factors related to pregnancy-related traits are understudied, especially among ancestrally diverse cohorts. This study assessed maternal contributions to hypertensive disorders of pregnancy (HDP) in multi-ancestry cohorts. MethodsWe performed a genome-wide association study of HDP using data from the Personalized Environment and Genes Study (PEGS) cohort (USA) with validation in the UK Biobank (UKBB). We performed gene-level and gene-set analyses and tested the association of polygenic scores (PGS) for systolic blood pressure (SBP), preeclampsia (PE), and gestational hypertension (GH). ResultsWe identified two novel maternal genome-wide significant associations with HDP. The lead independent variants were rs114954125 on chromosome 2 (near LRP1B; OR (95% CI): 3.03 (2.05, 4.49); P=3.19 - 10-8) and rs61176331 on chromosome 3 (near RARB; OR (95% CI): 3.09 (2.11, 4.53); P=7.97x10-9). We validated rs61176331 in the UKBB (P=3.73 - 10-2). When aggregating SNPs by genes, RARB (P=1.36 - 10-3) and RN7SL283P (P=2.56 - 10-2) were associated with HDP. Inflammatory and immunological biological pathways were most strongly related to HDP-associated genes. While all blood pressure and HDP-related PGS were significantly associated with HDP in PEGS, the SBP PGS was a stronger predictor of HDP (area under the curve (AUC): 0.57; R2=0.7%) compared to the PE PGS (AUC: 0.53; R2=0.2%). ConclusionOur study is the first to identify and validate maternal genetic variants near RARB associated with HDP. The findings demonstrate the power of multi-ancestry studies for genetic discovery and highlight the relationship between immune response and HDP and the utility of PGS for risk prediction. ClinicalTrials.gov Identifier for PEGS: NCT00341237

Angiotensin II (AngII) causes hypertension and vascular inflammation both directly and indirectly via cytokines. In vascular smooth muscle cells (VSMCs) AngII and TNF activate NADPH oxidase 1 (Nox1) to produce superoxide. TNF receptors associate with Nox1 and Leucine Rich Repeat Containing 8A (LRRC8A) anion channels to modulate inflammation, as well as contractility in a RhoA-dependent manner. VSMC-specific LRRC8A knockout (KO) mesenteric arteries are protected from TNF-induced injury and vasodilated better. We hypothesized that LRRC8A KO would preserve vascular function and decrease blood pressure (BP) in AngII-infused mice. Wild type (WT) and LRRC8A KO mice received AngII infusions for 14 days. Systolic BP was not different, but KO mice had more BP "dipping" during inactive periods and dipping was preserved after AngII. Contraction of KO mesenteric vessels to AngII itself was not altered, however after AngII exposure the function of KO aortic and mesenteric vessels was less impaired as reflected by less augmented contraction to norepinephrine and serotonin and preserved relaxation to acetylcholine and sodium nitroprusside. Western blotting revealed increased soluble guanylate cyclase alpha and reduced CPI-17 in hypertensive KO aortae. Consistent with the presence of lower Rho kinase activity in KO VSMCs, phosphorylation of Ezrin/Radixin/Moesin (ERM) and Cofilin was reduced. Aortic wall/lumen was not different between hypertensive WT and KO mice, but AngII caused less proliferation (lower PCNA), and less induction of antioxidant enzymes and senescence markers in KO vessels. Thus, while AngII-induced contraction does not require LRRC8A, these channels support the associated inflammatory response which modifies BP dipping.

Hypertension (HTN) has been associated with a greater risk of affective disorders. Paradoxically, several studies have shown the opposite effect in which high blood pressure relates to less depressive symptoms and greater well-being. Here we dissolve this paradox and clarify the relationship between mental health, blood pressure and the development of HTN using the UK Biobank. In adjusted multiple linear regression models, we found that the presence of a HTN diagnosis was associated with impaired mental health (i.e. more depressive symptoms (N = 303,771; {beta} = 0.043; 95% CI [0.039, 0.047]; p<0.001) and lower well-being scores (N = 129,876; {beta} = -0.057; 95% CI [-0.064, - 0.050]; p<0.001)) at baseline, whereas higher systolic blood pressure (SBP) was associated with fewer depressive symptoms (N = 303,771; {beta} = -0.063; 95% CI [-0.067, -0.060]; p<0.001) and higher well-being scores (N = 129,876; {beta} = 0.057; 95% CI [0.051, 0.063]; p<0.001). These effects persisted until follow-up ([~]10 years later). To explore a potential link between the mental health-blood pressure association and the development of HTN, we compared participants who were normotensive at baseline and developed HTN until follow-up with those who stayed normotensive. Notably, the adjusted model showed impaired mental health already at baseline in HTN developers (i.e., before HTN diagnosis; depressive symptoms: {beta} = 0.060; 95% CI [0.045, 0.076]; p<0.001; well-being: {beta} = -0.043; 95% CI [-0.068, -0.017]; p<0.001), indicating that people who develop HTN might require higher blood pressure levels for the same mental health outcomes as normotensives. In addition, the negative association between SBP and depressive symptoms at baseline was moderated by HTN development ({beta} = -0.014; 95% CI [-0.026, -0.003]; p=0.015), suggesting that the negative relationship between mental health and blood pressure was accentuated in people developing HTN several years before receiving their HTN diagnosis. We further observed that higher SBP was associated with lower emotion-related brain activity from functional magnetic resonance imaging (fMRI; {beta} = -0.032 95% CI [-0.045, -0.019]; p<0.001). This effect was also moderated by HTN diagnosis, suggesting an impact of SBP and HTN on the central nervous processing of emotions. Possible mechanisms are discussed, including regulatory baroreceptor circuits linking arterial blood pressure to neural processing of emotions. Overall, our results show an interrelation between mental health and blood pressure that may be involved in the development of HTN. In people who develop HTN, this relationship seems to be altered, such that higher blood pressure is required to sustain mental health, potentially offering a novel perspective for developing preventive and therapeutic measures.

BACKGROUNDHypertension is a common condition worldwide, yet its underlying mechanisms remain largely unknown. This study aims at identifying urinary peptides associated with hypertension to further explore its molecular pathophysiology. METHODSPeptidome data from 2876 individuals without end-organ damage were retrieved from the Human Urinary Proteome Database general population (discovery) or type 2 diabetic (validation) cohorts. Participants were divided based on systolic and diastolic blood pressure (SBP and DBP) into hypertensive (SBP[&ge;]140mmHg and/or DBP[&ge;]90mmHg) and normotensive (SBP<120mmHg and DBP<80mmHg, without antihypertensive treatment) groups. Differences in peptide abundance between the two groups were confirmed using an external cohort (n=420) of participants without end-organ damage, matched for age, body-mass index, eGFR, sex and presence of diabetes. Further, associations of the peptides with BP as a continuous variable were investigated. Findings were compared with peptide biomarkers of chronic diseases and bioinformatics analyses were conducted to potentially highlight the underlying molecular mechanisms. RESULTSBetween hypertensive and normotensive individuals, ninety-six (mostly COL1A1 and COL3A1) peptides were found significantly different in the discovery (adjusted) as well as the validation (nominal significance) cohorts with consistent regulation. Of these peptides, 83 were also consistently regulated in the matched cohort. A weak, yet significant association between their abundance and standardized BP was also observed. CONCLUSIONSHypertension is associated with an altered urinary peptide profile, with evident collagen differential regulation. Peptides related to vascular calcification and sodium regulation are also affected. Whether these modifications reflect the pathophysiology of hypertension per se and/or early subclinical target organ damage warrants further investigation. Novelty and RelevanceO_ST_ABSWhat is New?C_ST_ABSThis is the first study demonstrating differential regulation of urinary peptides in hypertensive patients, independent from other co-factors like age, diabetes, or established kidney or cardiovascular disease. What is Relevant?The observed changes in urinary peptides indicate individual differences in molecular changes observed in hypertension, and may guide personalized treatment based on the observed molecular changes Clinical/Pathophysiological Implications?The results indicate that collagen homeostasis may be a key molecular feature in hypertension and may serve as an attractive mechanism for pharmacological intervention.

ObjectiveWe investigated the independent and comparative association of a history of hypertensive disease of pregnancy and elevated serum soluble fms-like tyrosine kinase 1 to placental growth factor (sFlt-1/PlGF) ratio during the second half of pregnancy with the development of HTN up to 15 years after delivery. Study Design: N=1,238 singleton pregnancies were part of a prospective birth cohort study that enrolled patients from 2006-2008. Serum sFlt-1/PlGF was collected at a median of 26.0 and 35.1 weeks gestation. Adjusted Cox proportional hazard models estimated hazard ratios and 95%CI for the time to diagnosis for Stage 1 and Stage 2 HTN within 15 years PP in association with diagnoses of HDP and interquartile range of sFlt-1/PlGF. We adjusted for confounders. ResultsOf the n=993 women, n=260 (29.18%) were diagnosed with stage 1 and n=169 (17.0%) with Stage 2 HTN within 15 years of delivering.A history of PE or a history of gestational hypertension were both significantly associated with developing HTN later in life with adjusted hazard ratios of 2.17 (95% CI, 1.44-3.28) and 3.50 (95% CI, 2.21-5.54). There was no significant association between the hazard of developing HTN and the sFlt/PlGF ratio. However, mean PlGF levels during pregnancy in those who remained normotensive in the follow-up were higher at 546.7 pg/mL (SD= 369.5) compared to 513.7 pg/mL (SD=389.9) in the group with stage 1 and stage 2 HTN combined and 471.7 pg/mL (SD=471.7) in the stage 2 only group (p=0.008 and p=0.001). ConclusionIn patients followed for up to 15 years after delivery, a clinical history of hypertensive disease of pregnancy was significantly associated with the hazard of developing HTN later in life, while elevated sFlt-1/PlGF biomarker levels were not.However, mean PlGF levels in the latter half of pregnancy were significantly lower in those who developed HTN later in life.