Annet Kirabo | Vanderbilt University Medical Center (original) (raw)

Papers by Annet Kirabo

Cardiovascular Research, Apr 14, 2022

The joy from eating does not come from the exclusivity of the food but instead from the sensitivi... more The joy from eating does not come from the exclusivity of the food but instead from the sensitivity that we eat it with (Nino Gruettke). Just like allergic reactions, blood pressure can increase or decrease depending on what we eat, and this can vary from individual to individual. For example, excess dietary salt increases blood pressure, leading to increased cardiovascular risk, and salt-sensitive people are particularly vulnerable. Hypertension remains the leading cause of cardiovascular morbidity and mortality despite aggressive and widespread use of blood pressure-lowering medications. 1 One of the biggest challenges is the residual cardiovascular risk in patients treated with antihypertensive medications. 2 Moreover, up to 15% of patients with hypertension are treatment-resistant 3 and cannot reach adequate blood pressure control with the available treatment options, representing a major unmet need to better understand and treat hypertension. Research in the last decade has demonstrated that inflammation is a key player in the development of hypertension, and both innate and adaptive immunity have been implicated. Ample evidence has shown that T cells infiltrate the perivascular space and the kidney, leading to cytokine release and subsequent endothelial and renal injuries that mediate end-organ damage in hypertension. 4 Immune cells that have been implicated in the genesis of hypertension include dendritic cells, macrophages, other myeloid cells, and B and T lymphocytes. 5-7 However, much remains to be learned on the precise roles of each component of the immune system within close liaison between inflammation and hypertension. Emerging evidence suggests a role of allergic immune signalling in hypertension. We recently discovered the role of eosinophils and eosinophil marker interleukin-5 in hypertension. 8 People with allergic conditions, such as asthma and allergic rhinitis, have higher blood pressure and prevalence of hypertension. 9 However, the precise mechanisms contributing to hypertension in allergy are not fully understood.

Biomolecules, Mar 7, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Frontiers in Physiology, Dec 22, 2022

Salt-sensitivity of blood pressure is an independent risk factor for cardiovascular disease and a... more Salt-sensitivity of blood pressure is an independent risk factor for cardiovascular disease and affects approximately half of the hypertensive population. While the precise mechanisms of salt-sensitivity remain unclear, recent findings on body sodium homeostasis and salt-induced immune cell activation provide new insights into the relationship between high salt intake, inflammation, and hypertension. The immune system, specifically antigen-presenting cells (APCs) and T cells, are directly implicated in salt-induced renal and vascular injury and hypertension. Emerging evidence suggests that oxidative stress and activation of the NLRP3 inflammasome drive high sodium-mediated activation of APCs and T cells and contribute to the development of renal and vascular inflammation and hypertension. In this review, we summarize the recent insights into our understanding of the mechanisms of salt-sensitive hypertension and discuss the role of inflammasome activation as a potential therapeutic target.

Kidney360, Sep 29, 2022

Salt-sensitive hypertension is a major risk factor for cardiovascular morbidity and mortality. Th... more Salt-sensitive hypertension is a major risk factor for cardiovascular morbidity and mortality. The pathophysiologic mechanisms leading to different individual BP responses to changes in dietary salt remain elusive. Research in the last two decades revealed that the immune system plays a critical role in the development of hypertension and related end organ damage. Moreover, sodium accumulates nonosmotically in human tissue, including the skin and muscle, shifting the dogma on body sodium balance and its regulation. Emerging evidence suggests that high concentrations of extracellular sodium can directly trigger an inflammatory response in antigen-presenting cells (APCs), leading to hypertension and vascular and renal injury. Importantly, sodium entry into APCs is mediated by the epithelial sodium channel (ENaC). Although the role of the ENaC in renal regulation of sodium excretion and BP is well established, these new findings imply that the ENaC may also exert BP modulatory effects in extrarenal tissue through an immune-dependent pathway. In this review, we discuss the recent advances in our understanding of the pathophysiology of salt-sensitive hypertension with a particular focus on the roles of APCs and the extrarenal ENaC.

Antioxidants & Redox Signaling, Dec 20, 2021

Significance: Salt sensitivity of blood pressure (SSBP) is an independent risk factor for mortali... more Significance: Salt sensitivity of blood pressure (SSBP) is an independent risk factor for mortality and morbidity due to cardiovascular disease, and disproportionately affects blacks and women. Several mechanisms have been proposed, including exaggerated activation of sodium transporters in the kidney leading to salt retention and water.Recent Advances: Recent studies have found that in addition to the renal epithelium, myeloid immune cells can sense sodium via the epithelial Na+ channel (ENaC), which leads to activation of the nicotinamide adenine dinucleotide phosphate oxidase enzyme complex, increased fatty acid oxidation, and production of isolevuglandins (IsoLGs). IsoLGs are immunogenic and contribute to salt-induced hypertension. In addition, aldosterone-mediated activation of ENaC has been attributed to the increased SSBP in women. The goal of this review is to highlight mechanisms contributing to SSBP in blacks and women, including, but not limited to increased activation of ENaC, fatty acid oxidation, and inflammation.Critical Issues: A critical barrier to progress in management of SSBP is that its diagnosis is not feasible in the clinic and is limited to expensive and laborious research protocols, which makes it difficult to investigate. Yet without understanding the underlying mechanisms, this important risk factor remains without treatment.Future Directions: Further studies are needed to understand the mechanisms that contribute to differential blood pressure responses to dietary salt and find feasible diagnostic tools. This is extremely important and may go a long way in mitigating the racial and sex disparities in cardiovascular outcomes. Antioxid. Redox Signal. 35, 1477–1493.

Physiology

Background: High salt consumption is associated with increased cardiovascular risk and higher mor... more Background: High salt consumption is associated with increased cardiovascular risk and higher morbidity and mortality in salt-sensitive hypertensives than in salt-resistant normotensives. Salt sensitivity of blood pressure (SSBP) is an independent predictor of death due to cardiovascular disease. Although the role of SMAD3 has been extensively studied in kidney fibrosis during renal artery stenosis and other cardiovascular disorders, the role of this pathway in immune cells contributing to SSBP is yet to be defined. Hypothesis: We hypothesized that antigen-presenting specific SMAD3, downstream of JAK2, mediates IsoLG-protein adducts formation, T cell activation, and inflammation and contributes to SSBP. Method. We enrolled two cohorts of participants. We isolated monocytes from cohort one, treated them with normal or high salt, and performed RNA-seq analysis. We used an inpatient salt load and salt depletion protocol to phenotype for salt-sensitive and salt-resistant participants in...

American Journal of Physiology-Heart and Circulatory Physiology, 2022

Salt-sensitivity of blood pressure (SSBP) affects 50% of the hypertensive and 25% of the normoten... more Salt-sensitivity of blood pressure (SSBP) affects 50% of the hypertensive and 25% of the normotensive populations. Importantly, SSBP is associated with increased risk for mortality in both populations independent of blood pressure. Despite its deleterious effects, the pathogenesis of SSBP is not fully understood. Emerging evidence suggests a novel role of bile acids in salt-sensitive hypertension and that they may play a crucial role in regulating inflammation and fluid volume homeostasis. Mechanistic evidence implicates alterations in the gut microbiome, the epithelial sodium channel (ENaC), the farnesoid X receptor, and the G protein-coupled bile acid receptor TGR5 in bile acid-mediated effects on cardiovascular function. The mechanistic interplay between excess dietary sodium-induced alterations in the gut microbiome and immune cell activation, bile acid signaling, and whether such interplay may contribute to the etiology of SSBP is still yet to be defined. The main goal of this ...

Arteriosclerosis, Thrombosis, and Vascular Biology, May 1, 2016

Fatty acid oxidation leads to formation of highly reactive isoketals that adduct to protein lysin... more Fatty acid oxidation leads to formation of highly reactive isoketals that adduct to protein lysines. We have shown that dendritic cells (DCs) from hypertensive mice accumulate isoketal-adducted proteins and promote T cell activation. In hypertension, the endothelium is activated to produce reactive oxygen species and to express adhesion molecules and chemokines that attract inflammatory cells. Human monocytes that traverse the endothelium differentiate into monocyte-derived DCs upon exposure to a pro-inflammatory state. We hypothesized that human endothelial cells exposed to mechanical stretch promote conversion of human monocytes into immunogenic DCs. We co-cultured human aortic endothelial cells (HAECs) with monocytes from normotensive human donors and exposed the HAEC monolayer to either normal cyclical stretch (5%) or hypertensive cyclical stretch (10%) using the Flexcell ® Tension System for 48 hours. We found that co-culture of monocytes with HAECs exposed to 10% mechanical stretch markedly increased monocyte mRNA expression of the Th17 polarizing cytokines IL-6, I-23A and IL-1β and monocyte chemokine CCL4 and the p22 phox subunit of the NADPH oxidase compared to 5% stretch. HAECs exposed to 10% stretch promoted monocyte in culture to differentiate into DCs, as evidenced by the surface expression of DC-SIGN, CD83 and the co-stimulatory marker CD86. These monocytes also had an accumulation of isoketal-adducted proteins compared to controls (69.73 ± 5.802 vs 10.79 ± 1.854 respectively, p = 0.0001) as evidenced by intracellular staining and flow cytometry. Monocytes co-cultured with 10%-stretched HAECs induced a 1,500-fold increase in CD4 + T cell proliferation and a 1,300-fold increase in CD8 + T cells proliferation as monitored by CFSE compared to 5% stretch controls. Conversely, monocytes-HAEC cultures exposed to 10% stretch and treated with STAT3 inhibitor, stattic, prevented both CD4 + and CD8 + T cell proliferation. These data show that endothelial cells exposed to mechanical stretch cross-talk with monocytes to promote their differentiation into immunogenic DCs potentially via the JAK/STAT3 pathway. These findings give insight into a new mechanism of lymphocyte activation in the vascular endothelium during hypertension.

The FASEB Journal

The mechanisms by which salt causes hypertension are poorly understood. We recently found that de... more The mechanisms by which salt causes hypertension are poorly understood. We recently found that dendritic cells (DCs), potent antigen presenting cells, sense salt through amiloride‐sensitive channels leading to activation of the NADPH oxidase and formation of immunogenic isolevuglandin (IsoLG)‐protein adducts. DCs cultured in a HS environment and adaptively transferred to mice prime the hypertensive response to a sub‐pressure dose of angiotensin II. To translate our animal finds to humans, we tested the hypothesis that increased NaCl activates human monocytes to a DC‐like inflammatory phenotype. We exposed monocytes from 17 human volunteers to normal physiological NaCl (NS: 150 mM/L), elevated NaCl (HS: 190 mM/L), or an equiosmoloar concentration of mannitol. Exposure of human monocytes to high salt, but not mannitol, increased formation of IsoLG‐adducts (mean fluorescent intensities ‐ NS: 1688±384, Mann: 1762±429, HS: 2381± 635 Mean± SEM, p<0.002) as well as the expression of DC ...

Hypertension, Sep 1, 2015

Immunological memory provides protection to repeated antigen challenges and is a cardinal feature... more Immunological memory provides protection to repeated antigen challenges and is a cardinal feature of adaptive immunity. We have previously shown that adaptive immunity contributes to hypertension and have observed memory T cells in several models. We hypothesized that memory T cells contribute to long-term renal damage in response to repeated hypertensive challenges. To impose repeated episodes of hypertension, we treated C57BL/6 mice with L-NAME (0.5mg/ml) in drinking water for two weeks, allowed a two-week normotensive interval and then fed high salt (4% NaCl) for three weeks. L-NAME followed by high salt increased SBP to 151 ± 14 mmHg and caused a two-fold increase in CD4 + and CD8 + memory T cells in the kidney and bone marrow, as identified by the surface marker CD44hi. Intracellular staining showed that memory T cells were predominant sources of the inflammatory cytokines IL-17A and IFN-γ. Development and reactivation of memory T cells require the interaction of CD27 on T cells with CD70 on antigen presenting cells. Flow cytometry revealed that L-NAME/High salt increased expression of CD70 on splenic macrophages by 5-fold and dendritic cells by 3-fold. Because memory T cells are a major source of IFN-γ, we examined the hypertensive response to the L-NAME/high salt protocol in IFN-γ -/- mice. The hypertension caused by L-NAME was identical between WT, CD70 -/- and IFN-γ -/- mice. In contrast, the hypertension induced by subsequent salt administration was markedly attenuated in CD70 -/- mice (123 ± 1.3 mmHg, p&amp;lt;0.02). Likewise, mice lacking IFN-γ developed blunted hypertension during the salt-feeding phase (127.6 ± 5.5 mmHg, p&amp;lt;0.04). Interestingly, CD70 -/- and IFN-γ -/- mice failed to develop memory T cell formation in the kidney. The L-NAME/high salt caused striking albuminuria and increased urinary N-gal in WT mice, and these were absent in CD70 -/- and IFN-γ -/- mice. In contrast, L-NAME/high salt had no effect on renal angiotensinogen levels. Thus, repeated hypertensive stimuli lead to accumulation of long-lived effector memory T cells that are major sources of inflammatory cytokines, which in turn promote renal dysfunction, salt sensitivity and hypertension. These studies provide further insight into how the adaptive immune system promotes hypertension.

Hypertension, Sep 1, 2012

The adaptive immune system contributes to development of hypertension but the mechanisms or antig... more The adaptive immune system contributes to development of hypertension but the mechanisms or antigens involved are not known. Isoketals (IsoKs) are products of arachidonic acid oxidation that can cross-link lysine residues on proteins which in turn can be immunogenic. We sought to determine if IsoK-modified proteins serve as neoantigens presented by dendritic cells (DCs) to activate T cells in hypertension. Superoxide production by DCs was increased 5-fold by angiotensin II infusion compared to sham treated mice (334.0±49.7 versus 65.8±4.5 pmol/mg protein). This was NADPH-dependent as it did not occur in the gp91 phox-/- mice. This increase in superoxide was associated with accumulation of IsoKs in DCs and activation of DC IL-6 production (1411.0±1330.2 versus 576.2±512.8 pg/ml). Treatment with a potent IsoK scavenger, 2-hydroxybenzylamine, markedly attenuated angiotensin II-induced hypertension (131.4 ± 9.4 mmHg versus 160.1 ± 5.1 mmHg in control mice). Finally we employed an immunization assay involving priming by adoptive transfer of DCs from either sham or angiotensin II-treated mice to naïve recipients. T cells from these recipients were then cultured for 10 days with DCs from either sham or angiotensin II treated mice. DCs from angiotensin II treated mice, but not sham mice, caused a striking activation of CD8 + cells in this assay, as reflected by proliferation and polarization to Tc1 and Tc17 phenotypes. These studies show that angiotensin II-induced hypertension activates DCs, in large part by causing superoxide production and formation of IsoKs. We propose that IsoK-modified proteins can be presented as neoantigens by DCs, which in turn trigger T cell activation leading to hypertension.

JACC: Basic to Translational Science, Jun 1, 2020

Visual Abstract

Hypertension, Sep 1, 2012

T cells have been implicated in the genesis of hypertension however the mechanisms and subtype of... more T cells have been implicated in the genesis of hypertension however the mechanisms and subtype of T cells involved are still poorly understood. Moreover, the manner by which T cells of various subtypes affect renal function remains poorly defined. Recently, we found that CD8 + T cells play a critical role in the blood pressure elevation caused by angiotensin II. We sought to determine if CD8 + T cells have a role in the renal responses to angiotensin II. In metabolic chamber studies, we found that wild-type mice excrete 80% of a saline load (10% of body weight) in 4 hours, and that this is decreased in response to angiotensin II to 60 ± 5% (p &amp;amp;lt; 0.05) in WT mice but not in CD8 -/- mice. In contrast, CD4 -/- mice demonstrate a markedly exaggerated anti-natriuretic and anti-diuretic response to angiotensin II (p &amp;amp;lt; 0.001). We also found that chronic angiotensin II infusion increases superoxide production in the renal cortex of WT and CD4 -/- mice, but not in CD8 -/- mice. In addition, we found that angiotensin II infusion caused significant hypertrophy of the renal arterioles (&amp;amp;lt; 25 μm diameter) as reflected by an increase in the media/lumen ratio in wild type and CD4 -/- mice, (1.5 to 4.5 and 2.9 to 5.3 respectively, p &amp;amp;lt; 0.05 for each), but to a lesser extent in CD8 -/- mice (1.8 to 3.3). We also observed that the number of arterioles 0-25 micron in diameter decreased from 16.5 and 15.5 to 11.8 and to 11.4/mm2 in wild type and CD4 -/- mice respectively in response to angiotensin II, but was not changed in CD8 -/- mice. Our study therefore shows a previously unrecognized role for CD8 + T cells in modulating renal sodium and volume retention, renal cortical superoxide production, vascular hypertrophy and rarefaction. Thus, CD8 + T cells are an important intermediate in the actions of angiotensin II on the kidney, and a potential therapeutic target.

Hypertension, Sep 1, 2014

We have previously shown that the pro-inflammatory cytokine, interleukin 17A (IL17A), is upregula... more We have previously shown that the pro-inflammatory cytokine, interleukin 17A (IL17A), is upregulated by angiotensin II and plays a critical role in promoting angiotensin II-induced hypertension and vascular dysfunction. However, the mechanism by which IL17A promotes hypertension is not known. Our preliminary studies demonstrated that angiotensin II-induced hypertension decreased sodium hydrogen exchanger 3 (NHE3) in the kidneys of IL17A-/- mice to a greater extent than in wild type (WT) mice. This likely enhances the pressure natriuresis in these mice and could explain the lower hypertensive response to angiotensin II in these animals. Serum glucocorticoid kinase 1 (SGK1) potentially regulates NHE3 in the kidney. Therefore, we hypothesized that IL17A upregulates SGK1 and NHE3 in the renal proximal tubule and that loss of IL17A would enhance natriuresis and diuresis. Using cultured human proximal tubule cells (HK-2 cells), we found that IL17A upregulated SGK1 mRNA expression 3.9±0.4 fold (n=4, p

American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2017

Hypertension, Nov 1, 2014

Recent studies have emphasized a role of adaptive immunity, and particularly T cells, in the gene... more Recent studies have emphasized a role of adaptive immunity, and particularly T cells, in the genesis of hypertension. We sought to determine the T cell subtypes that contribute to hypertension and renal inflammation in angiotensin II-induced hypertension. Using T cell receptor (TCR) spectratyping to examine TCR usage we demonstrated that CD8 + cells, but not CD4 + cells, in the kidney exhibited altered TCR transcript lengths in Vβ3, 8.1 and 17 families in response to angiotensin II-induced hypertension. Clonality was not observed in other organs. The hypertension caused by angiotensin II in CD4 −/− and MHCII −/− mice was similar to that observed in WT mice, while CD8 −/− mice and OT1xRAG-1 −/− mice, which have only one TCR, exhibited a blunted hypertensive response to angiotensin II. Adoptive transfer of panT cells and CD8 + T cells but not CD4 + /CD25 − cells conferred hypertension to RAG-1 −/− mice. In contrast, transfer of CD4 + / CD25 + cells to wild type mice receiving angiotensin II decreased blood pressure. Mice treated with angiotensin II exhibited increased numbers of kidney CD4 + and CD8 + T cells. In response to a sodium/volume challenge, wild type and CD4 −/− mice infused with angiotensin II retained water and sodium whereas CD8 −/− mice did not. CD8 −/− mice were also protected against angiotensininduced endothelial dysfunction and vascular remodeling in the kidney. These data suggest that in the development of hypertension, an oligoclonal population of CD8 + cells accumulate in the kidney and likely contribute to hypertension by contributing to sodium and volume retention and vascular rarefaction.

Hypertension, Sep 1, 2017

Several studies have established a relationship between hypertension and salt intake; however the... more Several studies have established a relationship between hypertension and salt intake; however the mechanisms by which salt causes hypertension are poorly understood. There is also evidence that sodium (Na+) accumulates in the interstitium with aging and hypertension in concentrations exceeding the plasma. We tested the hypothesis that increased NaCl would convert human monocytes to an inflammatory phenotype and to define mechanisms involved. We exposed monocytes from 17 human volunteers to normal physiological NaCl (NS: 150 mM/L), elevated NaCl (HS: 190 mM/L), or an equiosmoloar concentration of mannitol. Exposure of human monocytes to high salt, but not mannitol, increased formation of immunogenic isolevuglandins (isoLG) (NS: 1688±384 vs Mann:1762±429 vs HS: 2381± 635 MFI p&amp;amp;amp;lt;0.002). This was associated with an increase in the dendritic cell (DC) marker CD83 (NS: 503±81 vs Mann: 530± 106 vs HS: 764 ± 136 MFI p&amp;amp;amp;lt;0.001). Exposure to high salt also stimulated production of IL-6 (NS: 2145±771, Mann: 1122±295 and HS: 5187±1146 pg/mL, p=0.04), IL-β (NS: 94±35, Mann: 62±16 and HS: 224±98 pg/mL, p=0.01) and TNF-α (NS:1.9±0.3, Mann: 3.42±1.4 and HS: 4.4±2.1, p&amp;amp;amp;lt;0.0001). In additional experiments, we found that prolonged (7 day) exposure to high salt increased surface expression of CD209, another DC marker (NS: 22±9 vs HS: 34 ± 14, p=0.001) and promoted conversion of the cells to a DC morphology. The propensity for monocytes to respond to NaCl was influence by the patient’s risk factors. The increase in IsoLG (HS-NS) correlated with pulse pressure (mmHg, r=0.51, &amp;amp;amp;lt;0.04), BMI (Kg/m2, r=0.66, p=0.005), total cholesterol (mg/dL, r=0.55, p&amp;amp;amp;lt;0.05) and glucose (mg/dL, r=0.72, p=0.003). Stepwise multivariate regression revealed that BMI and pulse pressure are independent predictors of IsoLG formation in response to salt. These findings suggest that high extracellular NaCl promotes differentiation and activation of monocytes and that these pleotropic inflammatory cells exhibit a previously undefined salt sensitivity corresponding to patients’ underlying risk factor profile.

The FASEB Journal, Apr 1, 2012

Arteriosclerosis, Thrombosis, and Vascular Biology, May 1, 2016

Background: The immune response plays a key role in the development of aortic dissection. In part... more Background: The immune response plays a key role in the development of aortic dissection. In particular, interferon gamma (IFNγ), produced by the T cell subsets, Th1 (CD4 + ) and Tc1 (CD8 + ), is elevated in human aortic dissection samples. Interestingly, a polymorphism in the gene SH2B3 that encodes LNK has been associated with several cardiovascular diseases in humans. LNK is an intracellular adaptor protein that has been shown to negatively regulate T cell activation and cytokine signaling. We hypothesized that LNK deficiency promotes aortic dissection through enhanced Th1/Tc1 responses. Methods: Angiotensin II (Ang II; 1000 ng/kg/min) was infused for 14 days into LNK -/- or WT mice in the absence or presence of an initial intraperitoneal injection of saline equal to 10% of their body weight. Kaplan-Meier survival curves were generated and flow cytometry, RT-PCR, histology were used to assess aortic inflammation and remodeling. Naïve CD4 + T cells from WT and LNK -/- mice were polarized ex vivo with Th1 polarizing cytokines and expression of IFNγ and T-bet were evaluated. Results: LNK -/- mice infused with Ang II exhibited an accelerated rate of aortic dissection or rupture compared to WT mice and this was exacerbated by saline injection prior to Ang II infusion (Figure). LNK -/- mice treated with salt plus Ang II exhibited increased aortic inflammation compared to WT mice. Aortic expression of IFNγ, T-bet and MMP9 were increased, while the expression of the procollagens type I and III were reduced in LNK -/- mice compared to WT mice. Ex vivo, naïve CD4 + T cells from LNK -/- mice expressed more T-bet and IFNγ compared to corresponding naïve T cells from WT mice when cultured under Th1 polarizing conditions. Conclusion: Loss of LNK enhances the Th1/Tc1 responses and promotes adverse aortic remodeling leading to development of aortic dissection and rupture. Targeting LNK and the Th1/Tc1 cell subsets could be a potential therapeutic strategy for the management of aortic dissection.

Social Science Research Network, 2018

Sodium accumulates in the interstitium and promotes inflammation through poorly defined mechanism... more Sodium accumulates in the interstitium and promotes inflammation through poorly defined mechanisms. We describe a pathway by which sodium enters dendritic cells (DCs) through amiloride-sensitive channels including the alpha and gamma subunits of the epithelial sodium channel and the sodium hydrogen exchanger 1. This leads to calcium influx via the sodium calcium exchanger, activation of protein kinase C (PKC), phosphorylation of p47 phox , and association of p47 phox with gp91 phox. The assembled NADPH oxidase produces superoxide with subsequent formation of immunogenic isolevuglandin (IsoLG)-protein adducts. DCs activated by excess sodium produce increased interleukin-1β (IL-1β) and promote T cell production of cytokines IL-17A and interferon gamma (IFN-γ). When adoptively transferred into naive mice, these DCs prime hypertension in response to a sub-pressor dose of angiotensin II. These findings provide a mechanistic link between salt, inflammation, and hypertension involving increased oxidative stress and IsoLG production in DCs.

Cardiovascular Research, Apr 14, 2022

The joy from eating does not come from the exclusivity of the food but instead from the sensitivi... more The joy from eating does not come from the exclusivity of the food but instead from the sensitivity that we eat it with (Nino Gruettke). Just like allergic reactions, blood pressure can increase or decrease depending on what we eat, and this can vary from individual to individual. For example, excess dietary salt increases blood pressure, leading to increased cardiovascular risk, and salt-sensitive people are particularly vulnerable. Hypertension remains the leading cause of cardiovascular morbidity and mortality despite aggressive and widespread use of blood pressure-lowering medications. 1 One of the biggest challenges is the residual cardiovascular risk in patients treated with antihypertensive medications. 2 Moreover, up to 15% of patients with hypertension are treatment-resistant 3 and cannot reach adequate blood pressure control with the available treatment options, representing a major unmet need to better understand and treat hypertension. Research in the last decade has demonstrated that inflammation is a key player in the development of hypertension, and both innate and adaptive immunity have been implicated. Ample evidence has shown that T cells infiltrate the perivascular space and the kidney, leading to cytokine release and subsequent endothelial and renal injuries that mediate end-organ damage in hypertension. 4 Immune cells that have been implicated in the genesis of hypertension include dendritic cells, macrophages, other myeloid cells, and B and T lymphocytes. 5-7 However, much remains to be learned on the precise roles of each component of the immune system within close liaison between inflammation and hypertension. Emerging evidence suggests a role of allergic immune signalling in hypertension. We recently discovered the role of eosinophils and eosinophil marker interleukin-5 in hypertension. 8 People with allergic conditions, such as asthma and allergic rhinitis, have higher blood pressure and prevalence of hypertension. 9 However, the precise mechanisms contributing to hypertension in allergy are not fully understood.

Biomolecules, Mar 7, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Frontiers in Physiology, Dec 22, 2022

Salt-sensitivity of blood pressure is an independent risk factor for cardiovascular disease and a... more Salt-sensitivity of blood pressure is an independent risk factor for cardiovascular disease and affects approximately half of the hypertensive population. While the precise mechanisms of salt-sensitivity remain unclear, recent findings on body sodium homeostasis and salt-induced immune cell activation provide new insights into the relationship between high salt intake, inflammation, and hypertension. The immune system, specifically antigen-presenting cells (APCs) and T cells, are directly implicated in salt-induced renal and vascular injury and hypertension. Emerging evidence suggests that oxidative stress and activation of the NLRP3 inflammasome drive high sodium-mediated activation of APCs and T cells and contribute to the development of renal and vascular inflammation and hypertension. In this review, we summarize the recent insights into our understanding of the mechanisms of salt-sensitive hypertension and discuss the role of inflammasome activation as a potential therapeutic target.

Kidney360, Sep 29, 2022

Salt-sensitive hypertension is a major risk factor for cardiovascular morbidity and mortality. Th... more Salt-sensitive hypertension is a major risk factor for cardiovascular morbidity and mortality. The pathophysiologic mechanisms leading to different individual BP responses to changes in dietary salt remain elusive. Research in the last two decades revealed that the immune system plays a critical role in the development of hypertension and related end organ damage. Moreover, sodium accumulates nonosmotically in human tissue, including the skin and muscle, shifting the dogma on body sodium balance and its regulation. Emerging evidence suggests that high concentrations of extracellular sodium can directly trigger an inflammatory response in antigen-presenting cells (APCs), leading to hypertension and vascular and renal injury. Importantly, sodium entry into APCs is mediated by the epithelial sodium channel (ENaC). Although the role of the ENaC in renal regulation of sodium excretion and BP is well established, these new findings imply that the ENaC may also exert BP modulatory effects in extrarenal tissue through an immune-dependent pathway. In this review, we discuss the recent advances in our understanding of the pathophysiology of salt-sensitive hypertension with a particular focus on the roles of APCs and the extrarenal ENaC.

Antioxidants & Redox Signaling, Dec 20, 2021

Significance: Salt sensitivity of blood pressure (SSBP) is an independent risk factor for mortali... more Significance: Salt sensitivity of blood pressure (SSBP) is an independent risk factor for mortality and morbidity due to cardiovascular disease, and disproportionately affects blacks and women. Several mechanisms have been proposed, including exaggerated activation of sodium transporters in the kidney leading to salt retention and water.Recent Advances: Recent studies have found that in addition to the renal epithelium, myeloid immune cells can sense sodium via the epithelial Na+ channel (ENaC), which leads to activation of the nicotinamide adenine dinucleotide phosphate oxidase enzyme complex, increased fatty acid oxidation, and production of isolevuglandins (IsoLGs). IsoLGs are immunogenic and contribute to salt-induced hypertension. In addition, aldosterone-mediated activation of ENaC has been attributed to the increased SSBP in women. The goal of this review is to highlight mechanisms contributing to SSBP in blacks and women, including, but not limited to increased activation of ENaC, fatty acid oxidation, and inflammation.Critical Issues: A critical barrier to progress in management of SSBP is that its diagnosis is not feasible in the clinic and is limited to expensive and laborious research protocols, which makes it difficult to investigate. Yet without understanding the underlying mechanisms, this important risk factor remains without treatment.Future Directions: Further studies are needed to understand the mechanisms that contribute to differential blood pressure responses to dietary salt and find feasible diagnostic tools. This is extremely important and may go a long way in mitigating the racial and sex disparities in cardiovascular outcomes. Antioxid. Redox Signal. 35, 1477–1493.

Physiology

Background: High salt consumption is associated with increased cardiovascular risk and higher mor... more Background: High salt consumption is associated with increased cardiovascular risk and higher morbidity and mortality in salt-sensitive hypertensives than in salt-resistant normotensives. Salt sensitivity of blood pressure (SSBP) is an independent predictor of death due to cardiovascular disease. Although the role of SMAD3 has been extensively studied in kidney fibrosis during renal artery stenosis and other cardiovascular disorders, the role of this pathway in immune cells contributing to SSBP is yet to be defined. Hypothesis: We hypothesized that antigen-presenting specific SMAD3, downstream of JAK2, mediates IsoLG-protein adducts formation, T cell activation, and inflammation and contributes to SSBP. Method. We enrolled two cohorts of participants. We isolated monocytes from cohort one, treated them with normal or high salt, and performed RNA-seq analysis. We used an inpatient salt load and salt depletion protocol to phenotype for salt-sensitive and salt-resistant participants in...

American Journal of Physiology-Heart and Circulatory Physiology, 2022

Salt-sensitivity of blood pressure (SSBP) affects 50% of the hypertensive and 25% of the normoten... more Salt-sensitivity of blood pressure (SSBP) affects 50% of the hypertensive and 25% of the normotensive populations. Importantly, SSBP is associated with increased risk for mortality in both populations independent of blood pressure. Despite its deleterious effects, the pathogenesis of SSBP is not fully understood. Emerging evidence suggests a novel role of bile acids in salt-sensitive hypertension and that they may play a crucial role in regulating inflammation and fluid volume homeostasis. Mechanistic evidence implicates alterations in the gut microbiome, the epithelial sodium channel (ENaC), the farnesoid X receptor, and the G protein-coupled bile acid receptor TGR5 in bile acid-mediated effects on cardiovascular function. The mechanistic interplay between excess dietary sodium-induced alterations in the gut microbiome and immune cell activation, bile acid signaling, and whether such interplay may contribute to the etiology of SSBP is still yet to be defined. The main goal of this ...

Arteriosclerosis, Thrombosis, and Vascular Biology, May 1, 2016

Fatty acid oxidation leads to formation of highly reactive isoketals that adduct to protein lysin... more Fatty acid oxidation leads to formation of highly reactive isoketals that adduct to protein lysines. We have shown that dendritic cells (DCs) from hypertensive mice accumulate isoketal-adducted proteins and promote T cell activation. In hypertension, the endothelium is activated to produce reactive oxygen species and to express adhesion molecules and chemokines that attract inflammatory cells. Human monocytes that traverse the endothelium differentiate into monocyte-derived DCs upon exposure to a pro-inflammatory state. We hypothesized that human endothelial cells exposed to mechanical stretch promote conversion of human monocytes into immunogenic DCs. We co-cultured human aortic endothelial cells (HAECs) with monocytes from normotensive human donors and exposed the HAEC monolayer to either normal cyclical stretch (5%) or hypertensive cyclical stretch (10%) using the Flexcell ® Tension System for 48 hours. We found that co-culture of monocytes with HAECs exposed to 10% mechanical stretch markedly increased monocyte mRNA expression of the Th17 polarizing cytokines IL-6, I-23A and IL-1β and monocyte chemokine CCL4 and the p22 phox subunit of the NADPH oxidase compared to 5% stretch. HAECs exposed to 10% stretch promoted monocyte in culture to differentiate into DCs, as evidenced by the surface expression of DC-SIGN, CD83 and the co-stimulatory marker CD86. These monocytes also had an accumulation of isoketal-adducted proteins compared to controls (69.73 ± 5.802 vs 10.79 ± 1.854 respectively, p = 0.0001) as evidenced by intracellular staining and flow cytometry. Monocytes co-cultured with 10%-stretched HAECs induced a 1,500-fold increase in CD4 + T cell proliferation and a 1,300-fold increase in CD8 + T cells proliferation as monitored by CFSE compared to 5% stretch controls. Conversely, monocytes-HAEC cultures exposed to 10% stretch and treated with STAT3 inhibitor, stattic, prevented both CD4 + and CD8 + T cell proliferation. These data show that endothelial cells exposed to mechanical stretch cross-talk with monocytes to promote their differentiation into immunogenic DCs potentially via the JAK/STAT3 pathway. These findings give insight into a new mechanism of lymphocyte activation in the vascular endothelium during hypertension.

The FASEB Journal

The mechanisms by which salt causes hypertension are poorly understood. We recently found that de... more The mechanisms by which salt causes hypertension are poorly understood. We recently found that dendritic cells (DCs), potent antigen presenting cells, sense salt through amiloride‐sensitive channels leading to activation of the NADPH oxidase and formation of immunogenic isolevuglandin (IsoLG)‐protein adducts. DCs cultured in a HS environment and adaptively transferred to mice prime the hypertensive response to a sub‐pressure dose of angiotensin II. To translate our animal finds to humans, we tested the hypothesis that increased NaCl activates human monocytes to a DC‐like inflammatory phenotype. We exposed monocytes from 17 human volunteers to normal physiological NaCl (NS: 150 mM/L), elevated NaCl (HS: 190 mM/L), or an equiosmoloar concentration of mannitol. Exposure of human monocytes to high salt, but not mannitol, increased formation of IsoLG‐adducts (mean fluorescent intensities ‐ NS: 1688±384, Mann: 1762±429, HS: 2381± 635 Mean± SEM, p<0.002) as well as the expression of DC ...

Hypertension, Sep 1, 2015

Immunological memory provides protection to repeated antigen challenges and is a cardinal feature... more Immunological memory provides protection to repeated antigen challenges and is a cardinal feature of adaptive immunity. We have previously shown that adaptive immunity contributes to hypertension and have observed memory T cells in several models. We hypothesized that memory T cells contribute to long-term renal damage in response to repeated hypertensive challenges. To impose repeated episodes of hypertension, we treated C57BL/6 mice with L-NAME (0.5mg/ml) in drinking water for two weeks, allowed a two-week normotensive interval and then fed high salt (4% NaCl) for three weeks. L-NAME followed by high salt increased SBP to 151 ± 14 mmHg and caused a two-fold increase in CD4 + and CD8 + memory T cells in the kidney and bone marrow, as identified by the surface marker CD44hi. Intracellular staining showed that memory T cells were predominant sources of the inflammatory cytokines IL-17A and IFN-γ. Development and reactivation of memory T cells require the interaction of CD27 on T cells with CD70 on antigen presenting cells. Flow cytometry revealed that L-NAME/High salt increased expression of CD70 on splenic macrophages by 5-fold and dendritic cells by 3-fold. Because memory T cells are a major source of IFN-γ, we examined the hypertensive response to the L-NAME/high salt protocol in IFN-γ -/- mice. The hypertension caused by L-NAME was identical between WT, CD70 -/- and IFN-γ -/- mice. In contrast, the hypertension induced by subsequent salt administration was markedly attenuated in CD70 -/- mice (123 ± 1.3 mmHg, p&amp;lt;0.02). Likewise, mice lacking IFN-γ developed blunted hypertension during the salt-feeding phase (127.6 ± 5.5 mmHg, p&amp;lt;0.04). Interestingly, CD70 -/- and IFN-γ -/- mice failed to develop memory T cell formation in the kidney. The L-NAME/high salt caused striking albuminuria and increased urinary N-gal in WT mice, and these were absent in CD70 -/- and IFN-γ -/- mice. In contrast, L-NAME/high salt had no effect on renal angiotensinogen levels. Thus, repeated hypertensive stimuli lead to accumulation of long-lived effector memory T cells that are major sources of inflammatory cytokines, which in turn promote renal dysfunction, salt sensitivity and hypertension. These studies provide further insight into how the adaptive immune system promotes hypertension.

Hypertension, Sep 1, 2012

The adaptive immune system contributes to development of hypertension but the mechanisms or antig... more The adaptive immune system contributes to development of hypertension but the mechanisms or antigens involved are not known. Isoketals (IsoKs) are products of arachidonic acid oxidation that can cross-link lysine residues on proteins which in turn can be immunogenic. We sought to determine if IsoK-modified proteins serve as neoantigens presented by dendritic cells (DCs) to activate T cells in hypertension. Superoxide production by DCs was increased 5-fold by angiotensin II infusion compared to sham treated mice (334.0±49.7 versus 65.8±4.5 pmol/mg protein). This was NADPH-dependent as it did not occur in the gp91 phox-/- mice. This increase in superoxide was associated with accumulation of IsoKs in DCs and activation of DC IL-6 production (1411.0±1330.2 versus 576.2±512.8 pg/ml). Treatment with a potent IsoK scavenger, 2-hydroxybenzylamine, markedly attenuated angiotensin II-induced hypertension (131.4 ± 9.4 mmHg versus 160.1 ± 5.1 mmHg in control mice). Finally we employed an immunization assay involving priming by adoptive transfer of DCs from either sham or angiotensin II-treated mice to naïve recipients. T cells from these recipients were then cultured for 10 days with DCs from either sham or angiotensin II treated mice. DCs from angiotensin II treated mice, but not sham mice, caused a striking activation of CD8 + cells in this assay, as reflected by proliferation and polarization to Tc1 and Tc17 phenotypes. These studies show that angiotensin II-induced hypertension activates DCs, in large part by causing superoxide production and formation of IsoKs. We propose that IsoK-modified proteins can be presented as neoantigens by DCs, which in turn trigger T cell activation leading to hypertension.

JACC: Basic to Translational Science, Jun 1, 2020

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Hypertension, Sep 1, 2012

T cells have been implicated in the genesis of hypertension however the mechanisms and subtype of... more T cells have been implicated in the genesis of hypertension however the mechanisms and subtype of T cells involved are still poorly understood. Moreover, the manner by which T cells of various subtypes affect renal function remains poorly defined. Recently, we found that CD8 + T cells play a critical role in the blood pressure elevation caused by angiotensin II. We sought to determine if CD8 + T cells have a role in the renal responses to angiotensin II. In metabolic chamber studies, we found that wild-type mice excrete 80% of a saline load (10% of body weight) in 4 hours, and that this is decreased in response to angiotensin II to 60 ± 5% (p &amp;amp;lt; 0.05) in WT mice but not in CD8 -/- mice. In contrast, CD4 -/- mice demonstrate a markedly exaggerated anti-natriuretic and anti-diuretic response to angiotensin II (p &amp;amp;lt; 0.001). We also found that chronic angiotensin II infusion increases superoxide production in the renal cortex of WT and CD4 -/- mice, but not in CD8 -/- mice. In addition, we found that angiotensin II infusion caused significant hypertrophy of the renal arterioles (&amp;amp;lt; 25 μm diameter) as reflected by an increase in the media/lumen ratio in wild type and CD4 -/- mice, (1.5 to 4.5 and 2.9 to 5.3 respectively, p &amp;amp;lt; 0.05 for each), but to a lesser extent in CD8 -/- mice (1.8 to 3.3). We also observed that the number of arterioles 0-25 micron in diameter decreased from 16.5 and 15.5 to 11.8 and to 11.4/mm2 in wild type and CD4 -/- mice respectively in response to angiotensin II, but was not changed in CD8 -/- mice. Our study therefore shows a previously unrecognized role for CD8 + T cells in modulating renal sodium and volume retention, renal cortical superoxide production, vascular hypertrophy and rarefaction. Thus, CD8 + T cells are an important intermediate in the actions of angiotensin II on the kidney, and a potential therapeutic target.

Hypertension, Sep 1, 2014

We have previously shown that the pro-inflammatory cytokine, interleukin 17A (IL17A), is upregula... more We have previously shown that the pro-inflammatory cytokine, interleukin 17A (IL17A), is upregulated by angiotensin II and plays a critical role in promoting angiotensin II-induced hypertension and vascular dysfunction. However, the mechanism by which IL17A promotes hypertension is not known. Our preliminary studies demonstrated that angiotensin II-induced hypertension decreased sodium hydrogen exchanger 3 (NHE3) in the kidneys of IL17A-/- mice to a greater extent than in wild type (WT) mice. This likely enhances the pressure natriuresis in these mice and could explain the lower hypertensive response to angiotensin II in these animals. Serum glucocorticoid kinase 1 (SGK1) potentially regulates NHE3 in the kidney. Therefore, we hypothesized that IL17A upregulates SGK1 and NHE3 in the renal proximal tubule and that loss of IL17A would enhance natriuresis and diuresis. Using cultured human proximal tubule cells (HK-2 cells), we found that IL17A upregulated SGK1 mRNA expression 3.9±0.4 fold (n=4, p

American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2017

Hypertension, Nov 1, 2014

Recent studies have emphasized a role of adaptive immunity, and particularly T cells, in the gene... more Recent studies have emphasized a role of adaptive immunity, and particularly T cells, in the genesis of hypertension. We sought to determine the T cell subtypes that contribute to hypertension and renal inflammation in angiotensin II-induced hypertension. Using T cell receptor (TCR) spectratyping to examine TCR usage we demonstrated that CD8 + cells, but not CD4 + cells, in the kidney exhibited altered TCR transcript lengths in Vβ3, 8.1 and 17 families in response to angiotensin II-induced hypertension. Clonality was not observed in other organs. The hypertension caused by angiotensin II in CD4 −/− and MHCII −/− mice was similar to that observed in WT mice, while CD8 −/− mice and OT1xRAG-1 −/− mice, which have only one TCR, exhibited a blunted hypertensive response to angiotensin II. Adoptive transfer of panT cells and CD8 + T cells but not CD4 + /CD25 − cells conferred hypertension to RAG-1 −/− mice. In contrast, transfer of CD4 + / CD25 + cells to wild type mice receiving angiotensin II decreased blood pressure. Mice treated with angiotensin II exhibited increased numbers of kidney CD4 + and CD8 + T cells. In response to a sodium/volume challenge, wild type and CD4 −/− mice infused with angiotensin II retained water and sodium whereas CD8 −/− mice did not. CD8 −/− mice were also protected against angiotensininduced endothelial dysfunction and vascular remodeling in the kidney. These data suggest that in the development of hypertension, an oligoclonal population of CD8 + cells accumulate in the kidney and likely contribute to hypertension by contributing to sodium and volume retention and vascular rarefaction.

Hypertension, Sep 1, 2017

Several studies have established a relationship between hypertension and salt intake; however the... more Several studies have established a relationship between hypertension and salt intake; however the mechanisms by which salt causes hypertension are poorly understood. There is also evidence that sodium (Na+) accumulates in the interstitium with aging and hypertension in concentrations exceeding the plasma. We tested the hypothesis that increased NaCl would convert human monocytes to an inflammatory phenotype and to define mechanisms involved. We exposed monocytes from 17 human volunteers to normal physiological NaCl (NS: 150 mM/L), elevated NaCl (HS: 190 mM/L), or an equiosmoloar concentration of mannitol. Exposure of human monocytes to high salt, but not mannitol, increased formation of immunogenic isolevuglandins (isoLG) (NS: 1688±384 vs Mann:1762±429 vs HS: 2381± 635 MFI p&amp;amp;amp;lt;0.002). This was associated with an increase in the dendritic cell (DC) marker CD83 (NS: 503±81 vs Mann: 530± 106 vs HS: 764 ± 136 MFI p&amp;amp;amp;lt;0.001). Exposure to high salt also stimulated production of IL-6 (NS: 2145±771, Mann: 1122±295 and HS: 5187±1146 pg/mL, p=0.04), IL-β (NS: 94±35, Mann: 62±16 and HS: 224±98 pg/mL, p=0.01) and TNF-α (NS:1.9±0.3, Mann: 3.42±1.4 and HS: 4.4±2.1, p&amp;amp;amp;lt;0.0001). In additional experiments, we found that prolonged (7 day) exposure to high salt increased surface expression of CD209, another DC marker (NS: 22±9 vs HS: 34 ± 14, p=0.001) and promoted conversion of the cells to a DC morphology. The propensity for monocytes to respond to NaCl was influence by the patient’s risk factors. The increase in IsoLG (HS-NS) correlated with pulse pressure (mmHg, r=0.51, &amp;amp;amp;lt;0.04), BMI (Kg/m2, r=0.66, p=0.005), total cholesterol (mg/dL, r=0.55, p&amp;amp;amp;lt;0.05) and glucose (mg/dL, r=0.72, p=0.003). Stepwise multivariate regression revealed that BMI and pulse pressure are independent predictors of IsoLG formation in response to salt. These findings suggest that high extracellular NaCl promotes differentiation and activation of monocytes and that these pleotropic inflammatory cells exhibit a previously undefined salt sensitivity corresponding to patients’ underlying risk factor profile.

The FASEB Journal, Apr 1, 2012

Arteriosclerosis, Thrombosis, and Vascular Biology, May 1, 2016

Background: The immune response plays a key role in the development of aortic dissection. In part... more Background: The immune response plays a key role in the development of aortic dissection. In particular, interferon gamma (IFNγ), produced by the T cell subsets, Th1 (CD4 + ) and Tc1 (CD8 + ), is elevated in human aortic dissection samples. Interestingly, a polymorphism in the gene SH2B3 that encodes LNK has been associated with several cardiovascular diseases in humans. LNK is an intracellular adaptor protein that has been shown to negatively regulate T cell activation and cytokine signaling. We hypothesized that LNK deficiency promotes aortic dissection through enhanced Th1/Tc1 responses. Methods: Angiotensin II (Ang II; 1000 ng/kg/min) was infused for 14 days into LNK -/- or WT mice in the absence or presence of an initial intraperitoneal injection of saline equal to 10% of their body weight. Kaplan-Meier survival curves were generated and flow cytometry, RT-PCR, histology were used to assess aortic inflammation and remodeling. Naïve CD4 + T cells from WT and LNK -/- mice were polarized ex vivo with Th1 polarizing cytokines and expression of IFNγ and T-bet were evaluated. Results: LNK -/- mice infused with Ang II exhibited an accelerated rate of aortic dissection or rupture compared to WT mice and this was exacerbated by saline injection prior to Ang II infusion (Figure). LNK -/- mice treated with salt plus Ang II exhibited increased aortic inflammation compared to WT mice. Aortic expression of IFNγ, T-bet and MMP9 were increased, while the expression of the procollagens type I and III were reduced in LNK -/- mice compared to WT mice. Ex vivo, naïve CD4 + T cells from LNK -/- mice expressed more T-bet and IFNγ compared to corresponding naïve T cells from WT mice when cultured under Th1 polarizing conditions. Conclusion: Loss of LNK enhances the Th1/Tc1 responses and promotes adverse aortic remodeling leading to development of aortic dissection and rupture. Targeting LNK and the Th1/Tc1 cell subsets could be a potential therapeutic strategy for the management of aortic dissection.

Social Science Research Network, 2018

Sodium accumulates in the interstitium and promotes inflammation through poorly defined mechanism... more Sodium accumulates in the interstitium and promotes inflammation through poorly defined mechanisms. We describe a pathway by which sodium enters dendritic cells (DCs) through amiloride-sensitive channels including the alpha and gamma subunits of the epithelial sodium channel and the sodium hydrogen exchanger 1. This leads to calcium influx via the sodium calcium exchanger, activation of protein kinase C (PKC), phosphorylation of p47 phox , and association of p47 phox with gp91 phox. The assembled NADPH oxidase produces superoxide with subsequent formation of immunogenic isolevuglandin (IsoLG)-protein adducts. DCs activated by excess sodium produce increased interleukin-1β (IL-1β) and promote T cell production of cytokines IL-17A and interferon gamma (IFN-γ). When adoptively transferred into naive mice, these DCs prime hypertension in response to a sub-pressor dose of angiotensin II. These findings provide a mechanistic link between salt, inflammation, and hypertension involving increased oxidative stress and IsoLG production in DCs.