bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P302: EFFECTS OF FINERENONE ON MYOCARDIAL INJURY AND SODIUM ACCUMULATION IN ALDOSTERONE-INFUSED RATS
Authors: Nishiyama Akira , Kitada Kento , Rahman Asadur
Published: October 2023

The aim of this study was to examine the effects of finerenone, a nonsteroidal mineralocorticoid receptor (MR) antagonist, on myocardial injury and sodium accumulation in rats subjected to aldosterone and salt treatment. Finerenone was administered orally at a dose of 10 mg/kg body weight, while aldosterone was given subcutaneously at a rate of 0.75 μg/hr and salt was provided in drinking water at a concentration of 1% NaCl. Aldosterone-infused rats experienced mortality within 30 days, while finerenone-treated rats did not. Echocardiography and gene expression analyses were conducted to evaluate cardiac remodeling and function in rats exposed to salt/aldosterone loading for 4 weeks. The results showed adverse cardiac remodeling and cardiac dysfunction with preserved ejection fraction in these rats. However, finerenone treatment completely prevented cardiac dysfunction and improved cardiac remodeling. Sodium accumulation in the left ventricular tissues was markedly elevated in salt/aldosterone-loaded rats, but significantly reduced in rats treated with finerenone. Furthermore, finerenone treatment significantly reduced gene expression of F4/80, a macrophage marker. In vitro studies with RAW 264.7 cells showed that sodium treatment increased mRNA expression of pro-inflammatory markers and upregulated NFAT5, a transcription factor that regulates genes involved in osmotic stress, while reducing the expression of anti-inflammatory markers. Finerenone treatment suppressed the elevation of pro-inflammatory markers and NFAT5, but did not affect anti-inflammatory gene levels. These findings suggest that finerenone protects against aldosterone-induced myocardial injury by suppressing sodium accumulation and subsequent inflammation, as well as adverse cardiovascular remodeling.
Abstract P305: New Screening Cutoff Values For Detection Of Aldosteronoma Examined By Lc-ms/ms And A Newly Developed Non-competitive Chemiluminescent Enzyme Immunoassay
Authors: Satoh Fumitoshi , Ono Yoshikiyo , Omata Kei , Tezuka Yuta , Ito Sadayoshi
Published: October 2023

Thinking of the poor accuracy of CLEIA and RIA measurements of plasma aldosterone concentrations (PACs), LC-MS/MS is the ideal method but it is costly, labor intensive and time consuming. A novel non-competitive CLEIA (NC-CLEIA) for measuring PACs was recently developed. We validated the accuracy and diagnostic ability of the NC-CLEIA as compared to PACs measured by LC-MS/MS and also determined the screen cutoffs by both measurements, respectively, detecting aldosterone-producing adenoma (APA) in hypertensive patients.

Method:
We measured plasma renin activity by enzyme assay and PACs using LC-MS/MS and NC-CLEIA in 133 APA, 100 bilateral hyperaldosteronism and 111 essential hypertension patients to examine the accuracy of PACs by this NC--CLEIA as compared with those by LC-MS/MS, and determine the screen cutoffs to detect APA. Passing-Bablok analysis revealed that NC-CLEIA (the regression slope, the intercept and the correlation coefficient were 0.962, -0.043, and 0.994, respectively), was significantly correlated and very equivalent to LC-MS/MS. Bland-Altman plot analysis of NC-CLEIA by LC-MS/MS also demonstrated much smaller systemic errors (a bias of -0.348 ng/dL with limits of agreement of -4.390 and 3.694 and 95% confidence interval) than those . The receiver-operating characteristics analysis demonstrated that cut-offs of aldosterone/renin activity ratio obtained by LC-MS/MS and NC-CLEIA were 31.2 and 31.5 (ng/dL per ng/mL/hr) with a sensitivity of 91.0% and 90.2%, and a specificity of 75.4% and 76.8%, respectively, to differentiate APA from non-APA. This novel NC-CLEIA for PAC could serve as a clinically reliable alternative to LC-MS/MS.
Abstract P310: Transcriptomic Profiling Of Sars-cov-2 Spike Protein S1 Subunit Mediated Changes In Human Vascular -pericytes, -endothelial Cells (ECs), -smooth Muscle Cells And Lymphatic ECs: Evidence For Differential Gene Regulation
Authors: Dubey Raghvendra K , Azzarito Giovanna , Leeners Brigitte , Rosselli Marinella
Published: October 2023

SARS-CoV-2 S1 spike protein (S1-SP) is increased in subjects with myocarditis after mRNA vaccine. However the underlying mechanism(s) of its vascular action are unclear. Using microarrays we assessed the effects of S1-SP on genes of vascular -ECs, -pericytes (PCs), -SMCs and LECs. Transcriptomic profiling of genes revealed that treatment of PCs, VECs, LECs and SMCs with 10ng/ml S1-SP for 36 hours upregulated 3935, 2512, 1422, 19 genes, respectively; and downregulated 3935, 3223, 1170, 37 genes, respectively. S1-SP significantly modulated genes in PCs, LECs and VECs, but not in SMCs. Pathway enrichment analysis highlighted modulation of TGF-β linked extracellular matrix, focal adhesion in PCS, VECs and LECs; whereas coronavirus disease, ribosome, cytoplasmic ribosomal protein, translation, protein metabolism, influenza infection, disease pathways were regulated in PCs and VECs, but not in LECs. A significant modulation in IL-2, cell senescence, IL4, TNFα and T-cell receptor associated apoptosis, Oncostatin M, p53 signaling was observed in LECs. Transcriptomic analysis showed induction of key COVID associated pro-inflammatory, coagulatory and matrix/adhesion molecules in PCs (PECAM1, CDH5, S1PR1, VWF, ESM1, EDN1, EFEMP1, ERG, ICAM2), but down regulation in VECs. Interestingly top genes that were down regulated in PCs (MYCT1, MMRN1, SEMA5A, GREM1, CEMIP, THBS2, BICC1, MYOCD, COL3A1, COL1A1, IGFBP3, PLPPR4, ITGA11, ADAMTS12, COL11A1, POSTN) were up regulated in VECs. Of all the genes regulated by S1-SP in PCs, VECs and LECs only two (FAP and P3H2) and eight (TMEM200A,MMP1, PLPP4, RGS5, TENM3, SULF1, COL12A1, SPOCK1) were up- and down regulated, respectively. DRG analysis highlighted contrasting modulation of genes associated with: myocarditis, metabolism (Glycolysis, one carbon metabolism, urea cycle and oxidative phosphorylation) and inflammation in PCs and VECs. No change in DRGs was observed in SMCs, whereas compared to PCs mixed regulation was observed in LECs. Also, Proteome array generated cytokine profile mimicked the impact of S1-SP on pro-inflammatory genes in PCs, VECs and LECs. Our findings provide first evidence that S1-SP differentially modulates genes and cytokines in PCs, LECs, VECs.
Abstract P320: Novel Alpha-calcitonin Gene Related Peptide Agonist Analogs In The Treatment Of Cardiovascular Disease
Authors: Kumar Ambrish , Dipette Donald J , Potts Jay D
Published: October 2023

Alpha-calcitonin gene related peptide (α-CGRP) is a potent vasodilator and protects against heart failure and hypertension in various animal models; however, rapid clearance of the peptide from the circulation makes it difficult to use as a therapeutic agent. Recently, we have synthesized two α-CGRP agonist analogs linked with two n-methoxyethylglycine (NMEG) peptoid molecules at either end: 1)- α-CGRP with NMEG molecules at the N-terminal end (N-ter NMEG), and 2)- α-CGRP with NMEG molecules at the C-terminal end (C-ter NMEG). Bioactivity and toxicity of modified peptides were evaluated in in vitro and in vivo conditions. Peptide-peptoid hybrids, N-ter NMEG and C-ter NMEG, were synthesized using a solid-phase peptide synthesis method with a >98% purity. To test the in vitro cell viability of the analogs, rat H9C2 cardiac myocyte cells were treated with 1 μM, 3 μM, and 10 μM concentrations of N-ter NMEG and C-ter NMEG peptides for 4 days followed by an MTT assay. Our in vitro results demonstrated that neither α-CGRP analogs were toxic to H9C2 cells. To test the bioactivity of these peptides, blood pressure (BP) was measured in wild-type C57BL6 mice using a tail-cuff BP analysis system. A bolus dose of 1.2, 3.6, and 12 (in mg/kg b.wt./mouse) of either peptide was injected subcutaneously (n= 4 mice/dose) followed by BP measurement at increasing time points. Our results demonstrate that there is a variance in the bioactivity of the two peptides. Subcutaneous delivery of N-ter NMEG reduced BP similar to the native peptide. After ten minutes of N-ter NMEG delivery, the BP (in mmHg ±SD) at a dose of 1.2 mg/kg was 76 ±5 (baseline BP= 118 ±15), at a dose of 3.6 mg/kg was 79 ±7 (baseline BP= 113 ±9), and at a dose of 12 mg/mg was 83 ±12 (baseline BP= 104 ±6). In contrast, C-ter NMEG administration did not reduce BP at any peptide concentration tested. In summary, in this study we determined that the α-CGRP analog N-ter NMEG, but not C-ter NMEG, is bioactive. Furthermore, N-ter NMEG showed no toxic effects on H9C2 cardiac myocytes in an in vitro viability assay. These results demonstrate that the analog N-ter NMEG is an effective α-CGRP agonist and a promising candidate molecule to treat cardiac diseases.
Abstract P321:
Authors: Ledoux Emily A , Gudelsky Alana , Tseng Claire C , Seehra Jasbir , Lachey Jennifer L
Published: October 2023

Rationale:
Imbalance in TGF-β signaling molecules SMAD2/3 and SMAD1/5/9 is a key driver of vascular dysfunction and pulmonary arterial hypertension (PAH) pathophysiology. KER-012, a novel ActRIIB ligand trap, designed to bind activin (Act) A and ActB to inhibit SMAD2/3: thereby permitting bone morphogenic protein (BMP) ligand signaling via SMAD1/5/9 to potentially rebalance TGF-β signaling and restore vascular homeostasis in PAH and associated disorders.

Methods:
Using hypoxia (1% O2) to mimic the pulmonary cell environment of PAH, we evaluated the effect of KER-012 or RKER -012 (a research form of KER-012) on TGF-β signaling in human pulmonary arterial endothelial cells (HPAECs) and smooth muscle cells (HPASMCs), two key cell types involved in the vascular remodeling in PAH. Gene expression of hypoxia/normoxia cultured cells was assessed by qPCR, phosphorylation of SMAD2 (pSMAD2) by alphaLISA, and ActA protein levels by ELISA.

Results:
HPAECs and HPASMCs both responded to TGF-β ligands implicated in PAH. ActA and Growth Differentiation Factor (GDF)11 increased SMAD2 phosphorylation and BMP9 increased SMAD1 phosphorylation (pSMAD1), confirming activation of the respective signaling pathways. KER-012 inhibited ActA and GDF11 induced pSMAD2, but not BMP9 induced pSMAD1. In hypoxic HPAECs, ActA gene expression increased >3-fold and BMPR2 expression decreased >2-fold relative to normoxia. ActA protein levels from hypoxic HPAEC supernatant also increased 10-fold, which was associated with an observed increase in pSMAD2 activation. While RKER-012 did not affect ActA gene expression, it did reduce ActA protein levels in supernatant to normoxic levels. This reduction in ActA may represent the fraction not bound to RKER-012, and potentially demonstrates a reduction in ActA availability for SMAD2/3 activation.

Conclusions:
ActA inhibition by RKER-012 restored homeostatic SMAD2 signaling in HPAECs and HPASMCs in an
in vitr
o PAH hypoxia model. RKER012 has also shown not to effect BMP signaling in these cells. These studies suggest that RKER-012 can potentially correct imbalanced SMAD signaling in PAH, partially via binding and inhibition of ActA protein.
Abstract P344: Effect Of Covid-19 Pandemic On Disparities In Blood Pressure Control In A Regional Healthcare System In Pennsylvania
Authors: Bucaloiu Andrei , Abedi Vida , Avula Venkatesh , Brown Jason P , Taher Mohamed F , Chang Alexander
Published: October 2023

Background:
Blood pressure (BP) control rates differ across gender, race, and ethnicity. The goal of our study was to examine the impact of the COVID-19 pandemic on disparities in BP control.

Methods:
Our study population was patients with uncontrolled hypertension (BP <130/80 for at least 2 years, diagnosis, or on medications) with an office visit in 2019 in a large regional Pennsylvania health system (Geisinger). We used logistic regression to evaluate associations between sociodemographic factors and 2 outcomes: 1) having an outpatient visit with BP measurement in 2020; 2) achieving BP control <130/80 in 2020.

Results:
Among individuals with hypertension in 2019, 37% (59,616 of 161,933) had BP <130/80 mmHg. Only 68.8% (70,361 of 102,317) of patients who had uncontrolled BP in 2019 had BP measured in 2020, compared to 74.9% (44,632 of 59,616) for those with controlled BP in 2019. Among patients with uncontrolled BP in 2019, younger patients, Black, Hispanic, and Native American patients were less likely to have BP measured in 2020 (Table). Among those who were uncontrolled in 2019 and had a follow-up in 2020, Black patients were significantly less likely to have BP controlled in 2020; females and older adults were significantly more likely to have controlled BP (Table).

Conclusion:
In a rural tertiary care center population, the COVID-19 pandemic deepened some preexisting disparities in BP control. More research is needed to inform interventions to address BP control disparities in the U.S.
Abstract P354: Leveraging Electronic Health Records For Quality Improvement Among Patients With Markedly Elevated Blood Pressure
Authors: Lu Yuan , Liu Yuntian , Krumholz Harlan M , Sussman Scott , Deshpande Ohm
Published: October 2023

Introduction:
Electronic health records (EHR) can improve quality of care for patients with markedly elevated blood pressure (BP). This study aimed to develop EHR-based computable algorithms to identify barriers to BP control and enhance triage and patient management.

Methods:
We conducted a retrospective analysis using EHR data from Yale New Haven Health System (YNHHS) employees and their dependents. Patients with markedly elevated BP had ≥2 outpatient BP readings ≥160/100 mmHg within a 180-day period. We assessed 3-month follow-up visits after BP elevation, along with the proportions of patients prescribed antihypertensives, filled prescriptions, and self-reported adherence using EHR data sources.

Results:
The study included 46,361 adult patients, with a mean age of 45.7 (14.5) years; 65% were female, 59% were White, and 17% were Black. Among them, 1,437 (3.3%) had markedly elevated BP, and 880 (1.9%) had consecutive markedly elevated BP readings. Among patients with markedly elevated BP, 626 (43.6%) had follow-up visits with relevant specialties within 3 months after the BP elevation. Moreover, 970 (67.5%) patients had antihypertensive prescriptions, of whom 927 (95.6%) filled their prescriptions, and among those who filled prescriptions, 806 (87.2%) reported taking the medications. Black patients were more likely to receive antihypertensive prescriptions but less likely to fill them or report taking medications (Figure).

Conclusion:
This study demonstrates the potential of EHR data and computable algorithms to enhance patient triage, interventions, and resource allocation for effective BP reduction among YNHHS employees.
Abstract P369: The Role Of Primary Cilia In The Pathogenesis And Therapy Of Hypertension In Polycystic Kidney Disease.
Authors: Aboualaiwi Wissam A , Saternos Hannah C , Forero Kathleen , Buqaileh Raghad J , Osman Islam , Messer William S
Published: October 2023

Primary cilia are sensory organelles, extending from the surface of vascular endothelialcells. Primary cilia dysfunctions have been linked to numerous genetic disorders,including polycystic kidney disease (PKD). Although PKD is characterized by fluid-filledcystic kidneys, cardiovascular complications such as hypertension (HTN) are the leadingcause of death in PKD patients. We demonstrated that primary cilia sense and transmitexternal mechanical stimuli such as fluid shear stress into internal biochemical reactionssuch as the release of nitric oxide (NO). This idea has
only
been investigated in ECs
invitro
. However, the importance of the vascular primary cilia in the long-term regulationof BP has not been investigated. NO-induced vasodilation is also produced in response tostimulation of eNOS by muscarinic acetylcholine receptor 3 (AChM3R) activation byacetylcholine (ACh). Using immunofluorescence staining, we generated new andsurprising data showing that AChM3R, and its signaling components, PIP2 are localizedto primary cilia and can modulate cilia function. We hypothesize that
primary ciliacontribute to BP regulation in PKD through AChM3R.
We showed that both, selective(cevimeline) and non-selective (ACh, CCh) activation of AChM3R led to an increase incilia length and cilia sensory function in terms of p-eNOS expression. We also generatedendothelial-specific (
Tie2Cre
and
VECre
)
AChM3R
KO mouse lines, in which
AChM3R
was deleted from the vascular endothelia. These mice developed high BP, as measured bytail cuff and telemetry blood pressure monitoring devices, associated with attenuated NOproduction and impaired vascular relaxation in response to ACh stimulation. Thesestudies demonstrated the physiological significance of primary cilia-derived NO in thelong-term control of vascular hemodynamics.
Abstract P378.2: Association Of
Foxo3
Longevity Genotype And Late-life Hypertension With Alzheimer’S Disease And Vascular Dementia
Authors: Morris Brian J , Chen Randi , Donlon Timothy A , Ross Webster , Kallianpur Kalpana , Willcox Bradley J , Allsopp Richard C , Nakagawa Kazuma , Masaki Kamal H
Published: October 2023

Genetic variants of the gene encoding the transcription factor FOXO3 are associated with cell resilience and longevity. Mid-life hypertension is associated with increased risk of vascular dementia and Alzheimer’s disease (AD) at older ages. But the findings for late life hypertension and AD are mixed. The aim of the present study was to determine whether
FOXO3
genotype might influence the association between late-life hypertension and incident dementia. Subjects were 2,688 American men of Japanese ancestry free of prevalent dementia at baseline (1991-93, baseline age: 77.0 ± 4.1 years, range 71-93 years) from the Kuakini Honolulu Heart Program. Status was known for
FOXO3 rs2802292
genotype, hypertension, and diagnosis of incident dementia to 2012. Association of
FOXO3
genotype with late-life hypertension and incident dementia, vascular dementia (VD) and Alzheimer’s disease (AD) was assessed using Cox proportional hazards models. During 21 years of follow-up, 725 men were diagnosed with all-cause dementia, 513 with AD and 104 with VD. A multivariable Cox model, adjusting for age, education,
APOE-ε4
and cardiovascular risk factors, showed late-life hypertension increased VD risk only (HR=1.71, 95%CI=1.08-2.71,
p
=0.022). We found no significant protective effect of
FOXO3
longevity genotype on any type of dementia at the population level. However, in a full Cox model adjusting for age, education,
APOE-ε4
and other cardiovascular risk factors, there was a significant interaction effect of late-life hypertension and
FOXO3
longevity genotypes on incident AD (β= -0.52,
p
=0.0061). In men with
FOXO3 rs2802292
longevity genotypes (
TG
/
GG
), late-life hypertension showed protection against AD (HR=0.72; 95% CI=0.55-0.95,
p
=0.021). The non-longevity genotype (
TT
) (HR=1.16; 95% CI=0.90-1.51,
p
=0.25) had no protective effect. In conclusion, our longitudinal study found that
FOXO3
genotype modulates the effect of late-life hypertension on incident AD.
Abstract P390: E-value Over P-value And Its Adjustments: Improving Dna Methylation Analysis With An Application To Hypertension Studies
Authors: Liu Pengyuan , Qiu Qiongzi , Yang Yifan , Liu Haoyuan , Liu Yi , Zhou Liyuan , Zheng Xiaoqi , Yue Rongxian , Mattson David L , Kidambi Vidya , Liang Mingyu , Pan Xiaoqing
Published: October 2023

DNA methylation plays a crucial role in transcriptional regulation. Reduced representation bisulfite sequencing (RRBS) is a technique of increasing use for analyzing genome-wide methylation profiles. Many computational tools such as Metilene, MethylKit, BiSeq and DMRfinder have been developed to use RRBS data to detect differentially methylated regions (DMRs) that may be involved in epigenetic regulations of gene expression. For DMR detection tools, as for countless other medical literature applications, P-values and their adjustments are among the most widely reported statistics used to assess the statistical significance of biological findings. However, P-values are coming under increasing criticism related to their questionable accuracy and relatively high levels of false positive or negative indications. Here, we proposed a method to calculate E-value for DMR detection in RRBS data, which is defined as likelihood ratios falling into the null hypothesis over the entire parameter space. We also provided the corresponding R package ‘
metevalue
’ as a user-friendly interface to implement E-value calculations into various DMR detection tools. To evaluate the performance of E-value, we generated various RRBS benchmarking datasets using our simulator ‘
RRBSsim
’ with 8 samples in each experimental group. Our comprehensive benchmarking analyses showed that using E-value not only significantly improved accuracy, AUC and power, over that of P-value or adjusted P-value, but also reduced false discovery rates and Type I errors. To illustrate the utility of E-value, we applied it to identify DMRs in two real RRBS datasets. One was genome-wide DNA methylome and transcriptome of renal T lymphocytes from Dahl Salt Sensitive rats treated with high- or low-salt diets. The other was genome-wide DNA methylation and gene expression data of human arterioles from our clinical trial in which 10 subjects were placed on 2-week low-salt diet (1200-mg sodium/day). Compared to the classical adjusted P-value, the use of E-value detected biologically more relevant DMRs and improved the negative association between DNA methylation and gene expression.
Abstract P392: Prdm6 Is An Embryonic Regulator Of Renin-producing Cells And Its Loss Of Function Causes Hypertension In Humans
Authors: Mani Arya , Gunawardhana Kushan , RUGIRA TROJAN
Published: October 2023

Essential hypertension is an inherited disease but its genetic causes are vastly not known. Genome-wide association studies (GWAS) have identified 5q23 as one of the strongest loci for hypertension in numerous populations with diverse ethnic backgrounds. Using massively parallel reporter and gene editing assays, we identified PRDM6 as the causal gene for hypertension at the 5q23 locus. Accordingly, mice deficient in smooth muscle cell (SMC) PRDM6 (Prdm6
fl/+
SM22-Cre )developed hypertension on a high salt diet. Mechanistically, loss of PRDM6 impaired the differentiation of renin-producing cells into smooth muscle cells, Sox6-dependent upregulation of renin-producing cells, and led to elevated plasma renin levels. Consistent with these findings, SMC-specific Sox6 KO mice exhibited very few renin-producing cells and normalized renin levels when they were intercrossed with Prdm6
fl/+
SM22-Cre mice. The blood pressure of Prdm6
fl/+
SM22-Cre mice was normalized with the renin inhibitor aliskiren. Strikingly, transcriptome analysis of the aorta showed that PRDM6 regulates 46 genes that are at GWAS peak loci for hypertension. These findings identify PRDM6 as a master regulator for blood pressure and as an attractive target for the development of antihypertensive drugs.
Abstract P398: Reduced Expression Of
Nfatc1
Protects Against Salt-sensitive Hypertension In Mice
Authors: Wang Yves T , Nguyen Nhu , Le Luan , Franceschini Nora , Le Thu H
Published: October 2023

Background:
While nuclear factor of activated T cells-cytoplasmic 1 (NFATc1) is a transcription factor that canonically plays a role in the immune response, it is also widely expressed in non-immune cells. A recent trans-ethnic meta-analysis of genome-wide association studies (GWAS) found that the
NFATC1
gene in humans was associated with chronic kidney disease. Additionally, renal
Nfact1
mRNA expression was decreased during high-salt exposure in a salt-sensitive murine model, suggesting a link between NFATc1 and salt-sensitive hypertension.

Methods:
Here, young adult heterozygous
Nfatc1
knockout mice (Het) and wild-type (WT) male mice on a salt-sensitive 129S6 background were studied. Systolic blood pressure (SBP) measurements were obtained by either tail cuff manometry with at least 2 weeks of training or implanted radiotelemetry with at least 2 weeks of recovery following surgery. SBP was recorded on standard chow (NSD), on a matched high-salt diet (HSD, 6% total NaCl), or on standard chow with 1000 ng/kg/min angiotensin II (AngII) delivered by osmotic minipump. Pressure natriuresis was examined by correlating 24 h SBP from telemetry with 24 h urine sodium collected in metabolic cages before and for 3 days after switching from NSD to HSD.

Results:
On NSD, there was no difference in SBP between WT and Het mice (127.8±9.9 vs 125.8±8.7 mmHg, n = 9/group). However, while WT mice displayed an expected elevation in SBP after 3 weeks on HSD, Het mice showed no change in SBP, resulting in a statistically significant difference between genotypes (143.4±8.9 vs 125.7±10.6 mmHg, p = 0.0024, n = 9/group). Pressure natriuresis curves were not significantly different between genotypes. SBP was not significantly different on AngII (167.6±22.2 vs 161.8±10.9 mmHg, n = 2/3).

Conclusion:
Our preliminary data shows that decreased
Nfatc1
expression protects against salt-sensitive hypertension. However, this effect is not mediated through a change in pressure natriuresis, suggesting possible involvement of a vascular mechanism. NFATc1 is a potential therapeutic target in salt-sensitive hypertension.
Abstract P399: High Salt Induced Mitochondrial Uncoupling And Enhanced Respiratory Activity In Isolated Proximal Tubules From Dahl Salt-sensitive Rats
Authors: Yang Chun , Dash Ranjan K , Kurth Terry , Shimada Satoshi , Cowley Allen W
Published: October 2023

The nephron actively reabsorbs ~99% of the Na
+
from the glomerular filtrate to maintain fluid and solute homeostasis, ~70% of which occurs in the proximal tubules (PT), where mitochondria consume a great amount of O
2
for ATP production to meet the energy demand. However, the effect of a high salt diet upon the PT energy metabolism and respiratory activity is not well-known. To determine this, the PT of Dahl salt-sensitive (SS) rats were isolated with the rats fed either 0.4% NaCl (LS) or 7, 14 and 21 days after feeding a 4.0% NaCl (HS) diet. Changes in O
2
consumption rate (OCR) of the PT were determined using a high-throughput Agilent Seahorse XF96 Extracellular Flux Analyzer and Mitochondrial Stress Test Protocol. Basal OCRs were assessed with only amino acids used as fuel for oxidative phosphorylation (OxPhos). Under these conditions, by day 7 of the HS diet, OCR increased from 9.2±0.5 to 17.2±0.8 pmol/min/μg, (p<0.05), which rose to 20.2±1.0 and 18.9±0.7 pmol/min/μg (p<0.05 vs LS), respectively, at HS day 14 and HS day 21. The Seahorse protocol was also modified to determine the OCR responses to representative circulating substrates. The OCR responses from baseline to glucose or pyruvate were unchanged by the HS diet compared to the PT of LS fed rats. However, a sustained increase in the proton leak OCR was observed for glucose (LS: 2.5±0.5 vs HS day 7: 7.3±1.1; p<0.05) and for pyruvate (LS: 2.3±0.3 vs HS day 7: 7.9±0.2; p<0.05). These high levels of proton leak were maintained throughout the 21 days of the HS diet. Since it is known that uncoupling proteins (UCP) and ADP/ATP translocase (ANT) enhance proton leak, gene expression was quantified from the isolated PT segments. Increased
Ucp2
expression was found (p<0.05) in response to the HS diet (days 7, 14, and 21) compared to LS fed rats but no changes were observed in the expression of
Slc25A4
(ANT1) or
Slc25A5
(ANT2). In summary, the HS diet resulted in increased PT O
2
consumption and proton leak in SS rats which was associated with an increase of
Ucp2
gene expression. Given recent evidence that this is associated with a decrease in renal blood flow (RBF/kidney wt), we propose that increases in the PT O
2
consumption contribute to the onset of regional chronic ischemia and exacerbates renal damage and hypertension.
Abstract P401: Caveolin-1 And Flotillin-1 Facilitates The SNX19-mediated D
1
R Endocytosis
Authors: Amatya Bibhas , Yang Jian , Konkalmatt Prasad , Asico Laureano , Armando Ines , Felder Robin , Jose Pedro A , Lee Hewang
Published: October 2023

Sorting nexin 19 (SNX19) belongs to the SNX-PXA-RGS-PXC subfamily of sorting nexins. It controls blood pressure by regulating the endocytosis of dopamine D1 receptor (D
1
R) in renal proximal tubule cells (RPTCs), allowing it to reside in the lipid rafts (LRs) of the plasma membrane. The exclusion of the D
1
R from LRs in RPTCs is associated with hypertension. However, it is unknown if SNX19 interacts with caveolin-1 and flotillin-1, two of the most important LR components. Thus, we studied if SNX19 associates with these two proteins and whether this interaction impacts D
1
R endocytosis. In RPTCs, SNX19 co-immunoprecipitated with caveolin-1 and flotillin-1 in basal conditions. Fenoldopam (FEN, 25nM, 30 min, n=3), a selective D
1
R/D
5
R agonist, increased the co-immunoprecipitation of SNX19 with both caveolin-1 and flotillin-1. The treatment with a D
1
R/D
5
R antagonist, SCH 39166 (SCH, 1 μM, 30 min), prevented the FEN-mediated increase in the co-immunoprecipitation of SNX19 with caveolin-1 and flotillin-1. In RPTCs, the transfection of SNX19 plasmid with deletion of either caveolin-1 (ΔCav1-SNX19) or flotilin-1(ΔFlot1-SNX19) binding domain impaired the FEN-mediated D
1
R endocytosis compared with the cells that were only transfected with wild-type (WT) SNX19 (WT-SNX19, 100.0±5.0%; ΔCav1-SNX19, 39.1±2.8%; ΔFlot1-SNX19, 59.6±3.4%, n=5). Moreover, the relative mRNA expression of SNX19 did not change in RPTCs transfected with WT-SNX19, ΔCav1-SNX19, or ΔFlot1-SNX19. Thus, SNX19 expression does not depend on its caveolin-1 or flotillin-1 binding motif. In C57Bl/6 mice fed with normal salt diet (0.9% NaCl), the renal subcapsular infusion of
Snx19
siRNA (3 μg/day,7 days) significantly increased systolic blood pressure (SBP, mmHg) (mock siRNA: 99.3±1.5, n=8;
Snx19
siRNA: 114.1±5.4, n=8). The SBP also increased in mice fed with high salt and aggravated by
Snx19
siRNA (4% NaCl; mock siRNA: 119.8 ± 5.6, n=4;
Snx19
siRNA: 125.6 ±3.4, n=5). Low salt diet decreased SBP that was not affected by
Snx19
siRNA (0.04% NaCl, mock siRNA: 92. 0 ± 3.5, n=3;
Snx19
siRNA: 82.7 ±6.7, n=3). Germline deletion of
Snx19
in C57Bl/6 mice fed with normal salt diet increased SBP. In conclusion, caveolin-1 and flotillin-1 are important for SNX19-mediated D
1
R endocytosis and blood pressure.
Abstract P402: Trends In Hypertension Phenotypes Over The Lifespan
Authors: Baughman Carter , Cluett Jennifer , Ishak Anthony , Turkson-Ocran Ruth-Alma , Larbi Kwapong Fredrick , Col Hannah , Lynn-Green Erika , Vyavahare Medha , Bandi Keerthi , Aung Naing , Mukamal Ken J , Juraschek Stephen P
Published: October 2023

Background:
White coat effects are thought to be more prevalent among older adults, while masked effects are thought to be more prevalent among younger adults. However, there are limited data examining these trends across the lifespan.

Objective:
To characterize trends in 24-hour ambulatory blood pressure monitoring (ABPM) measures and discordant HTN phenotypes across age groups.

Methods:
We extracted data from ABPMs conducted at a Boston academic medical center between 2019 and 2023. Data were examined in 20-yr age groups: <40, 40-59, 60-79, and ≥80 years. We determined the mean systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and pulse pressure (PP) by age group. Office BP (OBP) and ABPM were used to derive the following HTN phenotypes: no HTN (OBP & ABPM <140/<90 mm Hg), white coat HTN (OBP ≥140/≥90 & ABPM <140/<90 mm Hg), masked HTN (OBP <140/<90 mm Hg & ABPM ≥140/≥90 mm Hg), and sustained HTN (both ≥140/≥90 mm Hg). Trends in BP measures and phenotypes were determined via linear or logistic regression adjusted for sex, race, and ethnicity.

Results:
Of 628 patients with ABPM, average age was 61.1±16.5 (62% female, 22% Black, and 8% Hispanic). Across age categories, SBP increased by 2.30 (95% CI: 1.0, 3.6) mm Hg, DBP decreased by 5.4 (-6.2,-4.5) mm Hg, HR decreased by 4.4 (-5.3,-3.5) bpm, and PP increased by 7.7 (6.5, 8.8) mm Hg (all
P
-trends across categories <0.001). In contrast, we did not observe significant trends in HTN phenotypes across age categories (
P
-trends >0.05) (
Table
).

Conclusions:
Age was associated with higher SBP and lower DBP, but not discordant HTN phenotypes. These findings are relevant for the interpretation of out-of-office BP measurements.
Abstract P405: Outcomes And Trends Of Hypertensive Crisis In Patients Aged 40 Years Or Younger: Results From National Inpatient Sample 2016-2020
Authors: Mehta Shivani , Mittal Vivek , Hassan Shahzad , Parajuli Tilachan , Qureshi Waqas
Published: October 2023

Introduction:
Hypertension is the leading modifiable risk factor of cardiovascular morbidity and mortality. The trends of hypertension and its complications in young individuals are not well studied.

Methods:
We examined hospitalized patients who were diagnosed with hypertensive crisis and were included in the National Inpatient Sample 2016-2020. Hypertensive crisis was defined by using international classification of disease -10. Patient aged less than 18 years and pregnant women were excluded. Multivariable logistic regression analysis was used to examine association of age 40 years or less and hypertensive crisis with primary outcome of mortality, and secondary outcomes. We also studied trends of hypertensive crisis in these patients.

Results:
There were 589,220 (mean age 61years±17, 55.7% female, 45% white) patients with hypertensive crisis. Out of these, 12.3% (n= 72,200) were aged less than 40 years. In the group of patients with age 40 years or younger, 0.13% (n= 90) died. The major secondary outcomes in this group were acute kidney injury (26%) with 15.4% requiring hemodialysis, acute heart failure (17.8%), and hypertensive encephalopathy (3.28%). The outcomes of hypertensive crisis in younger patients are shown in
figure 1
. From 2016-2020, there are decreasing yearly trends of hypertensive crisis in these patients (p= 0.004) and no statistically significant trends in mortality (p =0.2)!.

Conclusion:
Hypertensive crisis brings morbidity and economic burden on the patients. A considerable number of young patients develop acute kidney injury and require hemodialysis. More studies directed towards young patients are needed to prevent these complications.
Abstract P407: Increased Secretion Of Glucose Dependent Insulinotropic Polypeptide Is Associated With Postprandial Hypotension In Patients With Parkinson Disease
Authors: Hay Kaitlyn R , Mehr Pouya , Wynn Amy E , Paranjape Sachin Y , Ding Tan , Iregui Jessica , Lonce Suzanna , Peacock Carly , Claassen Daniel O , Shibao Cyndya A
Published: October 2023

Postprandial hypotension (PPH) is highly prevalent in Parkinson Disease (PD) and is defined as a sudden and substantial decrease (>20 mm Hg or >10 mm hg) in blood pressure within two hours after ingesting a meal. This condition is associated with syncope and falls. Eating a meal induces significant blood sequestration in the splanchnic circulation through the release of gastrointestinal (GI) hormones. Patients with autonomic dysfunction cannot compensate for these hemodynamic changes, which results in PPH. The purpose of this study is to evaluate if increased secretion of GI hormones, including glucose-dependent insulinotropic polypeptide (GIP), a strong splanchnic vasodilator, contributes to PPH in those with PD. We enrolled 11 PD patients, seven with PPH (PPH+) (age 69±7.65 years old, 72% males, Unified Parkinson’s Disease Rating Scale 29±18.9) and four without PPH (PPH-) (age 67±1.71 years, 75% males, UPDRS 20±15.30). PD PPH+ patients had evidence of autonomic impairment and orthostatic hypotension as defined by a change in systolic blood pressure, (-57±29.23 vs. -7±17.66 mm Hg in PPH). Blood pressure, heart rate, and blood GIP levels were measured before and at 5, 10, 15, 30, 60, 90, 120 min timepoints after 75 gr oral glucose in supine position. There was a time-dependent decrease in blood pressure with a nadir at 30 min (-17±14.30 mmHg vs. -5±17.26 in PPH-). In PD PPH+, peak GIP secretion also occurred at 30 min post-glucose ingestion (315.3±297.9 vs. 69.1±34.8 pmol/L in PPH-). PD PPH+ patients had a greater secretion of C-peptide (2141±1017.81 vs.1540.56±428.77 pmol/L in PPH-) and insulin (1477.78±1572.80 vs. 351.09±141.53 pmol/L in PPH-). These initial results show excessive GIP secretion in PD patients with PPH, suggesting that GIP may contribute to its pathophysiology.
Abstract P408: Treatment Of Orthostatic Hypotension With Pyridostigmine: Relevance To Supine Hypertension
Authors: Okamoto Luis E , Walsh Emily , Shibao Cyndya A , Gamboa Alfredo , Diedrich Andre , Black Bonnie , Biaggioni Italo
Published: October 2023

Supine hypertension, a common comorbidity in patients with orthostatic hypotension (OH), creates a management challenge because the treatment of one condition can worsen the other. Treatment of OH with the acetylcholinesterase inhibitor pyridostigmine has the advantage of preferentially increasing upright blood pressure (BP) by facilitating autonomic ganglia neurotransmission. We did a retrospective analysis of 37 patients with neurogenic OH (65±2 yr, 21 men) to study the efficacy of pyridostigmine 60 mg (defined as the increase in upright systolic BP [SBP] 1-hr postdrug) and determine clinical predictors of efficacy. Pyridostigmine increased upright SBP by 4 (-6 to 11 mmHg, median, IQR). Pyridostigmine efficacy was inversely correlated with the severity of OH (the SBP drop on standing, r
2
=0.4, p=0.022) and with the magnitude of autonomic impairment, the ratio of the increase in heart rate on standing divided by the drop in SBP, (r
2
=0.32, p=0.044) only in patients with central autonomic failure and intact efferent sympathetic pathways (multiple system atrophy, MSA; n=13), but not in patients with pure autonomic failure (PAF; n=24). Pyridostigmine efficacy was negatively correlated to supine BP (r
2
=0.20, p=0.006; Figure). In conclusion, pyridostigmine was less effective in patients with severe autonomic impairment and those with supine hypertension, who are most likely to benefit from the preferential increase in upright BP produced by the drug. PAF patients had severe OH (-74±6 vs. -56±8 mmHg in MSA), and our results may not reflect patients with milder OH.
Abstract P420: Changes In Cardiac Oxidative Stress Is Protected In Intrauterine Growth Restricted Females Vs Males Before The Development Of Hypertension And Cardiovascular Diseases
Authors: Castillo Angie , Smith Jonna , Smith Savanna , Jones Kylie
Published: October 2023

Preeclampsia (PE) is a pregnancy complication characterized by hypertension (HTN) typically during the third trimester. PE is the leading cause for intrauterine growth restricted (IUGR) offspring (OFS). Women with PE and their OFS (IUGR) are at a higher risk for developing cardiovascular diseases (CVD) later in life. Two major factors that contribute to the development of CVDs are HTN and oxidative stress (OS). Studies show that human and animals adult IUGR OFS have a higher risk of developing HTN and CVDs compared to females later in life. The rationale for these sex differences is unknown; and we hypothesize that male IUGR rats will have elevated cardiac oxidative stress, while female IUGR will have lower cardiac OS .To test, we will examine sex differences between 12 week IUGR and control (CON) OFS that are not hypertensive, to determine if there are any change in cardiac OS before the development of HTN and CVD.

Methods:
Sprague Dawley rats were divided into 4 groups: IUGR male, IUGR female, and control (CON) male and female. IUGR rats were derived from the OFS reduced uterine perfusion pressure (RUPP) PE rat model. CON OFS were from normal pregnant rats. At 12wk, BP was measured via carotid catheterization. Heart tissue was collected to assess oxidative stress, via examining reactive oxygen species (ROS) Heat shock protein 1 (HSP-1) and hydrogen peroxide (H2O2). Antioxidants were measured via manganese superoxide dismutase (MnSOD), copper zinc superoxide dismutase (CuZnSOD) and antioxidant capacity (AC). There were no significant changes in HSP-1, CuZnSOD, and H2O2 between male and female OFS. However, female IUGR OFS had a 20% increase in antioxidant MnSOD (119.9 ± 6.133 vs 93.98 ± 5.197 %MnSOD U/protein/CON, p <0.05) compared to CON in the heart. Male OFS had no significant changes for MnSOD. IUGR female AC had a 2-fold increase in activity (22.13 ± 1.019 vs 14.15 ± 1.852 mM Trolox/mg protein, p <0.05) compared to its CON. Furthermore, IUGR male OFS had a slight decrease in AC compared to CON male (11.00 ± 1.420 vs 13.24 ± 0.4676 mM Trolox/mg protein, ns). The significant increase of AC and MnSOD in IUGR female OFS suggests that females may be more protected from OS, via mitochondria-specific antioxidants compared to males.
Abstract P428: Angiotensin II Type 1 Receptor-associated Protein Deletion Combined With Angiotensin II Stimulation Exacerbates Diabetic Kidney Disease In C57BL/6 Mice
Authors: Azushima Kengo , Taguchi Shinya , Wakui Hiromichi , Tamura Kouichi
Published: October 2023

The progress in the research field of diabetic kidney disease (DKD) has been disturbed by the lack of reliable animal models. Angiotensin II (Ang II) type 1 receptor (AT1R)-associated protein (ATRAP) promotes internalization of AT1R and selectively inhibits pathological AT1R signaling. In this study, we investigated whether overactivation of the renin-angiotensin system (RAS) through a combination of ATRAP deletion with Ang II stimulation developed a progressive DKD model in C57BL/6 mice, which are resistant to the development of kidney injury. Eight-week-old male systemic ATRAP-knockout mice on the C57BL/6 strain (KO) and their littermate wild-type mice (Ctrl) were divided into five groups: 1) Ctrl, 2) Ctrl-streptozotocin (STZ), 3) KO-STZ, 4) Ctrl-STZ-Ang II, and 5) KO-STZ-Ang II. Ang II was administered for 6 weeks from 4 weeks after STZ administration. At 10 weeks after STZ administration, mice were euthanized to evaluate kidney injuries after measurements of systolic blood pressure (SBP) and urinary albumin excretion (UAE). Neither ATRAP deletion alone nor Ang II stimulation alone developed a progressive DKD model in STZ-induced diabetic C57BL/6 mice (UAE, Ctrl vs Ctrl-STZ vs KO-STZ vs Ctrl-STZ-Ang II: 10.6±2.0 vs 89.0±11.9 vs 69.1±15.0 vs 151.3±55.4 μg/day). However, a combination of ATRAP deletion with Ang II stimulation accelerated the development of DKD as manifested by overt albuminuria (UAE, KO-STZ-Ang II: 852.0±195.6 μg/day,
p
<0.001 vs Ctrl-STZ-Ang II), glomerular hypertrophy, podocyte loss, mesangial expansion, kidney interstitial fibrosis, and functional insufficiency, concomitant with increased angiotensinogen and AT1R expression in the kidneys. SBP levels were comparable between the Ctrl-STZ-Ang II and KO-STZ-Ang II groups (SBP, Ctrl-STZ-Ang II vs KO-STZ-Ang II: 144±4 vs 154±5 mmHg,
p
=0.363). In STZ-induced diabetic C57BL/6 mice, the combination of ATRAP deletion and Ang II stimulation accelerates the development of DKD by converting the C57BL/6 strain from being nephropathy-resistant to -susceptible, which may be associated with intrarenal RAS overactivation.
Abstract P433: Evidence For An Important Role Of AT1a Receptors In The Renomedullary Interstitial Cells In Basal Blood Pressure Homeostasis And The Development Of Angiotensin Ii-induced Hypertension
Authors: Li Xiao C , Hassan Rumana , Sato Ryosuke , Katsurada Akemi , Hao Chuan-Ming , Zhang Mingzhi , Harris Raymond C , Zhuo Jia L
Published: October 2023

The renomedullary interstitial cells (RMICs) are highly specialized lipid-laden interstitial fibroblasts, which form characteristic "ladder-like" structural associations with adjacent microvessels and renal tubules in the kidney medulla. We have previously reported that RMICs express abundant AT
1
(AT
1a
) receptors
in vitro
and
in vivo
, but the physiological role of AT
1
(AT
1a
) receptors in RMICs has not been determined. In the present study, we generated and phenotyped for the 1
st
time a new mutant mouse model with RMIC-selective deletion of AT
1a
receptors in the kidney medulla, RMIC-

Agtr1a
-/-

, using an innovative inducible

Tenascin-C-CreER2/Agtr1a
f/f

approach. Deletion of AT
1a
receptors selectively in RMICs did not alter the development and cellular structures in the kidney medulla of RMIC-

Agtr1a
-/-

mice. The heart wt. to body wt. ratio was lower (
P
<0.01), whereas the kidney wt. to body wt. ratio was significantly higher (
P
<0.01) in RMIC-
Agtr1a
-/-
than wild-type (WT) mice without altering heart rate. Compared with WT mice, basal systolic, diastolic, and mean arterial blood pressure, as measured by the telemetry technique, were significantly lower in adult male RMIC-

Agtr1a
-/-

mice (WT: 122 ± 3 mmHg vs. RMIC-

Agtr1a
-/-

: 103 ± 4 mmHg,
P
<0.01). The decreases in basal blood pressure in RMIC-

Agtr1a
-/-

mice was associated with significantly lower urine excretion (WT: 1.56 ± 0.15 mL/24 h vs. RMIC-

Agtr1a
-/-

: 0.98 ± 0.13 mL/24 h,
P
<0.01), urinary sodium (WT: 207.9 ± 7.3 μmol/24 h vs. RMIC-

Agtr1a
-/-

: 145.2 ± 5.4 μmol/24 h,
P
<0.01), potassium excretion (WT: 221.0 ± 6.7 μmol/24 h vs. RMIC-

Agtr1a
-/-

: 160.8 ± 10.6 μmol/24 h,
P
<0.01), and markedly decreased urine osmolality in RMIC-

Agtr1a
-/-

mice (WT: 1724 ± 335 mOsm/Kg H
2
O vs. RMIC-

Agtr1a
-/-

: 1128 ± 102 mOsm/Kg H
2
O,
P
<0.01). Ang II infusion (0.5 mg/kg/day, i.p., 2 weeks) increased blood pressure to 148 ± 5 mmHg in WT mice, as expected, but it increased only to 129 ± 8 mmHg without further altering urine osmolality from controls in RMIC-

Agtr1a
-/-

mice (
P
<0.01). In conclusion, the present study provides new evidence for the 1st time for an important role of AT
1a
receptors in RMICs in maintaining basal blood pressure homeostasis and the development of Ang II-induced hypertension.