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Objectives: γδ T-lymphocytes play a role in angiotensin II (AngII)-induced hypertension, vascular injury and T-cell infiltration in perivascular adipose tissue (PVAT) in mice. Mesenteric arteries of hypertensive mice and subcutaneous arteries from obese humans present similar remodeling. We hypothesized that γδ T-cell subtypes in mesenteric vessels with PVAT (MV/PVAT) from hypertensive mice and subcutaneous adipose tissue (SAT) from obese humans, who are prone to develop hypertension, would be similar., Methods: Mice were infused with AngII for 14 days. MV/PVAT T-cells were used for single-cell RNA-sequencing (scRNA-seq). scRNA-seq data (GSE155960) of SAT CD45 + cells from three lean and three obese women were downloaded from the Gene Expression Omnibus database., Results: δ T-cell subclustering identified six δ T-cell subtypes. AngII increased T-cell receptor δ variable 4 ( Trdv4 ) + γδ T-effector memory cells and Cd28high δ T EM -cells, changes confirmed by flow cytometry. δ T-cell subclustering identified nine δ T-cell subtypes in human SAT. CD28 expressing δ T-cell subclustering demonstrated similar δ T-cell subpopulations in murine MV/PVAT and human SAT. Cd28+ γδ NKT EM and Cd28high δ T EM -cells increased in MV/PVAT from hypertensive mice and CD28high δ T EM -cells in SAT from obese women compared to the lean women., Conclusion: Similar CD28 + δ T-cells were identified in murine MV/PVAT and human SAT. CD28 high δ T EM -cells increased in MV/PVAT in hypertensive mice and in SAT from humans with obesity, a prehypertensive condition. CD28 + δ T-lymphocytes could have a pathogenic role in human hypertension associated with obesity, and could be a potential target for therapy., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Extracellular ATP is elevated in hypertensive mice and humans and may trigger immune activation through the purinergic receptor P2X7 (P2RX7) causing interleukin-1β production and T-cell activation and memory T-cell development. Furthermore, P2RX7 single nucleotide polymorphisms (SNP) are associated with hypertension. We hypothesized that P2RX7 activation contributes to hypertension and cardiovascular injury by promoting immune activation., Methods: Male wild-type and P2rx7-/- mice were infused or not with angiotensin II (AngII) for 14 days. A second group of AngII-infused wild-type mice were co-infused with the P2RX7 antagonist AZ10606120 or vehicle. BP was monitored by telemetry. Cardiac and mesenteric artery function and remodeling were assessed using ultrasound and pressure myography, respectively. T cells were profiled in thoracic aorta/perivascular adipose tissue by flow cytometry. Associations between SNPs within 50 kb of P2RX7 transcription, and BP or hypertension were modeled in 384 653 UK Biobank participants., Results: P2rx7 inactivation attenuated AngII-induced SBP elevation, and mesenteric artery dysfunction and remodeling. This was associated with decreased perivascular infiltration of activated and effector memory T-cell subsets. Surprisingly, P2rx7 knockout exaggerated AngII-induced cardiac dysfunction and remodeling. Treatment with a P2RX7 antagonist reduced BP elevation, preserved mesenteric artery function and reduced activated and effector memory T cell perivascular infiltration without adversely affecting cardiac function and remodeling in AngII-infused mice. Three P2RX7 SNPs were associated with increased odds of DBP elevation., Conclusion: P2RX7 may represent a target for attenuating BP elevation and associated vascular damage by decreasing immune activation., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

A subset of interleukin (IL)-17A-producing γδ T cells called γδT17 cells may contribute to progression of hypertension. γδT17 cell development is in part dependent upon IL-23 receptor (IL-23R) stimulation. We hypothesized that angiotensin (Ang) II-induced blood pressure (BP) elevation and vascular injury would be blunted in Il23r knock-in (Il23r gfp/gfp ) mice deficient in functional IL-23R. To test this hypothesis, we infused wild-type (WT) and Il23r gfp/gfp mice with Ang II (490 ng/kg/min, SC) for 7 or 14 days. We recorded BP by telemetry, assessed vascular function and remodeling using pressurized myography, and profiled T cell populations and cytokine production by flow cytometry. An additional set of Il23r gfp/gfp mice was infused with Ang II for 7 days and injected with interferon (IFN)-γ-neutralizing or control antibodies. Il23r gfp/gfp mice had smaller and stiffer mesenteric arteries and were not protected against Ang II-induced BP elevation. BP was higher in Il23r gfp/gfp mice than WT mice from day 3 until day 9 of Ang II infusion. Il23r gfp/gfp mice had less γδT17 cells and more IFN-γ-producing γδ, CD4 + , and CD8 + T cells than WT mice. Seven days of Ang II infusion led to increased IFN-γ-producing γδ, CD4 + , and CD8 + T cells in Il23r gfp/gfp mice, whereas only IFN-γ-producing γδ T cells were increased in WT mice. Blocking IFN-γ with a neutralizing antibody reduced the pressor response to 7 days of Ang II infusion in Il23r gfp/gfp mice. Functional IL-23R deficiency was associated with increased IFN-γ-producing T cells and exaggerated initial development of Ang II-induced hypertension, which was in part mediated by IFN-γ., (© 2022. The Author(s), under exclusive licence to The Japanese Society of Hypertension.)

Objective: Hypertension is associated with vascular injury, which contributes to end-organ damage. MicroRNAs regulating mRNAs have been shown to play a role in vascular injury in hypertensive mice. We aimed to identify differentially expressed microRNAs and their mRNA targets in small arteries of hypertensive patients with/without chronic kidney disease (CKD) to shed light on the pathophysiological molecular mechanisms of vascular remodeling., Methods and Results: Normotensive individuals and hypertensive patients with/without CKD were recruited ( n  = 15-16 per group). Differentially expressed microRNAs and mRNAs were identified uniquely associated with hypertension (microRNAs: 10, mRNAs: 68) or CKD (microRNAs: 68, mRNAs: 395), and in both groups (microRNAs: 2, mRNAs: 32) with a P less than 0.05 and a fold change less than or greater than 1.3 in subcutaneous small arteries ( n  = 14-15). One of the top three differentially expressed microRNAs, miR-338-3p that was down-regulated in CKD, presented the best correlation between RNA sequencing and reverse transcription-quantitative PCR (RT-qPCR, R2  = 0.328, P  < 0.001). Profiling of human aortic vascular cells showed that miR-338-3p was mostly expressed in endothelial cells. Two of the selected top nine up-regulated miR-338-3p predicted targets, glutathione peroxidase 3 ( GPX3 ) and protein tyrosine phosphatase receptor type S ( PTPRS ), were validated with mimics by RT-qPCR in human aortic endothelial cells ( P  < 0.05) and by a luciferase assay in HEK293T cells ( P  < 0.05)., Conclusion: A distinct transcriptomic profile was observed in gluteal subcutaneous small arteries of hypertensive patients with CKD. Down-regulated miR-338-3p could contribute to GPX3 and PTPRS up-regulation via the canonical microRNA targeting machinery in hypertensive patients with CKD., http://links.lww.com/HJH/C27., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Mechanisms of blood pressure (BP) regulation by endothelin (ET)-1 produced by endothelial cells are complex and remain unclear. Long-term exposure to human ET-1 (hET-1) in mice inducibly overexpressing hET-1 in the endothelium (ieET-1) caused sustained BP elevation. ET-1 has been shown to stimulate the release of aldosterone. Whether aldosterone plays a role in hET-1 overexpression-induced BP elevation and vessel injury is unknown., Method: Nine- to 12-week-old male ieET-1 mice and control mice expressing a tamoxifen-inducible Cre recombinase (CreERT2) in the endothelial cells (ieCre) were treated with tamoxifen for 5 days and studied 3 months later., Results: Endothelial hET-1 overexpression increased plasma aldosterone levels, which was reversed by 2-week treatment with atrasentan, an endothelin type A receptors blocker. Aldosterone synthase and cryptochrome 2 adrenal cortex mRNA expression was decreased in ieET-1 mice. Two-week treatment with eplerenone, a mineralocorticoid receptor antagonist, reduced systolic BP by 10 mmHg in ieET-1 mice during rest time. Saline challenge-induced sodium excretion and renal cortex thiazide-sensitive sodium-chloride cotransporter mRNA expression were decreased in ieET-1 mice. The sensitivity of mesenteric arteries to contraction by norepinephrine was increased in ieET-1 mice, and was abrogated by eplerenone treatment, whereas sensitivity of endothelium-independent relaxation responses to sodium nitroprusside was enhanced. Resistance artery remodeling was reduced in eplerenone-treated ieET-1 vs. ieET-1 and ieCre mice., Conclusion: These results demonstrate that aldosterone contributes to BP elevation and vascular norepinephrine sensitivity and remodeling caused by hET-1 overexpression in endothelium in mice., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Chromosome 2 introgression from normotensive Brown Norway (BN) rats into hypertensive Dahl salt-sensitive (SS) background (SS-chromosome 2 BN /Mcwi; consomic S2 B ) reduced blood pressure and vascular inflammation under a normal-salt diet (NSD). We hypothesized that BN chromosome 2 contains anti-inflammatory genes that could reduce blood pressure and vascular inflammation in rats fed NSD or high-salt diet (HSD). Four- to 6-week old male SS and congenic rats containing the BN chromosome 2 distal portion (SS.BN-[ rs13453786-rs66377062 ]/Aek; S2 B a) and middle segment (SS.BN-[ rs106982173-rs65057186 ]/Aek; S2 B b) were fed NSD or HSD (4% NaCl) up to age 12 to 13 weeks. Systolic blood pressure determined by telemetry was higher in SS rats fed HSD versus NSD. Systolic blood pressure was lower in both congenic rats than in SS under NSD, but similar under HSD versus SS. Reactive oxygen species generation using dihydroethidium staining, expression of vascular cell adhesion molecule-1 and monocyte chemoattractant protein-1, and immune cell infiltration by immunofluorescence demonstrated that S2 B a rats present less inflammation under NSD and more under HSD versus SS rats. RNA sequencing and reverse transcription-quantitative PCR identified 2 differentially expressed genes encoded within BN chromosome 2 distal portion that could act as regulators of vascular inflammation. These were downregulated glutamyl aminopeptidase ( Enpep ) that was anti-inflammatory under NSD and upregulated heparan sulfate 2-O-sulfotransferase 1 ( Hs2st1 ) that was proinflammatory under HSD. In conclusion, 2 differentially expressed genes encoded within introgressed BN chromosome 2 distal fragment were identified: Enpep associated with reduced vascular inflammation under NSD, and Hs2st1 , associated with increased vascular inflammation under HSD.

Background: Hypertension (HTN) is associated with target organ damage such as cardiac, vascular, and kidney injury. Several studies have investigated circulating microRNAs (miRNAs) as biomarkers of cardiovascular disease, but few have examined them as biomarker of target organ damage in HTN. We aimed to identify circulating miRNAs that could serve as biomarkers of HTN-induced target organ damage using an unbiased approach., Methods and Results: Fifteen normotensive subjects, 16 patients with HTN, 15 with HTN associated with other features of the metabolic syndrome (MetS), and 16 with HTN or chronic kidney disease (CKD) were studied. Circulating RNA extracted from platelet-poor plasma was used for small RNA sequencing. Differentially expressed (DE) genes were identified with a threshold of false discovery rate <0.1. DE miRNAs were identified uniquely associated with HTN, MetS, or CKD. However, only 2 downregulated DE miRNAs (let-7g-5p and miR-191-5p) could be validated by reverse transcription-quantitative PCR. Let-7g-5p was associated with large vessel stiffening, miR-191-5p with MetS, and both miRNAs with estimated glomerular filtration rate (eGFR) and neutrophil and lymphocyte fraction or number and neutrophil-to-lymphocyte ratio. Using the whole population, stepwise multiple linear regression generated a model showing that let-7g-5p, miR-191-5p, and urinary albumin/creatinine ratio predicted eGFR with an adjusted R2 of 0.46 (P = 8.5e-7)., Conclusions: We identified decreased circulating let-7g-5p and miR-191-5p as independent biomarkers of CKD among patients with HTN, which could have pathophysiological and therapeutic implications., (© American Journal of Hypertension, Ltd 2020. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Vascular injury is an early manifestation in hypertension and a cause of end-organ damage. MicroRNAs play an important role in cardiovascular disease, but their implication in vascular injury in hypertension remains unclear. This study revealed using an unbiased approach, microRNA and mRNA sequencing with molecular interaction analysis, a microRNA-transcription factor coregulatory network involved in vascular injury in mice made hypertensive by 14-day Ang II (angiotensin II) infusion. A candidate gene approach identified upregulated miR-431-5p encoded in the conserved 12qF1 (14q32 in humans) microRNA cluster, whose expression correlated with blood pressure, and which has been shown to be upregulated in human atherosclerosis, as a potential key regulator in Ang II-induced vascular injury. Gain- and loss-of-function in human vascular smooth muscle cells demonstrated that miR-431-5p regulates in part gene expression by targeting ETS homologous factor. In vivo miR-431-5p knockdown delayed Ang II-induced blood pressure elevation and reduced vascular injury in mice, which demonstrated its potential as a target for treatment of hypertension and vascular injury.

Endothelium-derived endothelin (ET)-1 has been implicated in the development of hypertension and end-organ damage, but its exact role remains unclear. We have shown that tamoxifen-inducible endothelium-restricted human ET-1 overexpressing (ieET-1) mice exhibited blood pressure rise after a 3-week induction in an ET type A (ET A ) receptor-dependent manner, in absence of vascular and renal injury. It is unknown whether long-term ET-1 overexpression results in sustained blood pressure elevation and vascular and renal injury. Adult male ieET-1 and control tamoxifen-inducible endothelium-restricted Cre recombinase (ieCre) mice were induced with tamoxifen and 2.5 months later, were treated with or without the ET A receptor blocker atrasentan for 2 weeks. Three-month induction of endothelial human ET-1 overexpression increased blood pressure ( P <0.01), reduced renal artery flow ( P <0.001), and caused mesenteric small artery stiffening ( P <0.05) and endothelial dysfunction ( P <0.01). These changes were accompanied by enhanced mesenteric small artery Col1A1 and Col3A1 expression, and perivascular adipose tissue oxidative stress ( P <0.05) and monocyte/macrophage infiltration ( P <0.05). Early renal injury was demonstrated by increased kidney injury molecule-1 expression in renal cortex tubules ( P <0.05), with, however, undetectable lesions using histochemistry staining and unchanged urinary albumin. There was associated increased myeloid (CD11b + ) and myeloid-derived suppressive cell (CD11b + Gr-1 + ) renal infiltration ( P <0.01) and greater frequency of myeloid and renal cells expressing the proinflammatory marker CD36 ( P <0.05). Atrasentan reversed or reduced all of the above changes ( P <0.05) except the endothelial dysfunction and collagen expression and reduced renal artery flow. These results demonstrate that long-term exposure to endothelial human ET-1 overexpression causes sustained blood pressure elevation and vascular and renal injury via ET A receptors., (© 2017 American Heart Association, Inc.)