bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 130: The Prognosis of Prehypertension Without Progression to Hypertension
Authors: Niiranen Teemu J , Larson Martin G , McCabe Elizabeth L , Vasan Ramachandran S , Cheng Susan
Published: March 2022

Although progression from prehypertension (preHTN) to hypertension (HTN) is preventable, the prognosis of preHTN among individuals who never progress to HTN and, in turn, the role of early- versus late-onset pre-HTN in this context remains unclear. Our sample consisted of 5593 Framingham Heart Study participants (mean age 43 years, 52% women) with mortality and serial blood pressure (BP) data available. We categorized participants into 5 BP phenotypes: never preHTN or HTN; late-onset (age ≥55 years) preHTN without ever developing HTN; early-onset (age <55 years) preHTN without ever developing HTN; late-onset HTN; and early-onset HTN. Cases were considered persons who died from cardiovascular disease (CVD) or specifically from coronary heart disease (CHD), and controls included the remaining decedents. We used multivariable-adjusted regression models to estimate case-vs-control odds ratios for the 4 preHTN/HTN categories versus those who died without ever developing preHTN or HTN. The loess-smoothed curves for mean BP values, by age, for the 5 BP phenotypes are shown in
Figure A.
Compared to individuals who maintained optimal BP throughout life, onset of preHTN earlier or later in life, without progression to HTN, did not significantly increase odds of CVD (
Figure B
) or CHD (
Figure C
) death. By contrast, late- and especially early-onset HTN were associated with considerably increased odds of CVD death and CHD death. Our study findings suggest that not all forms of preHTN are associated with the same magnitude of risk for CVD death. Further investigations are needed to determine whether interventions aimed at preventing the progression from preHTN to HTN could improve outcomes.
Abstract 137: Sox6 Regulates Renin Expression During Juxtaglomerular Cell Expansion
Authors: Foss Jason D , Xiao Liang , Horton Kandi D , Saleem Mohammad , Hodgkinson Conrad P , Harrison David G , Gomez Jose A
Published: March 2022

Introduction:
Hypertension, a common condition that affects 33% of the US population, is a major risk factor for heart disease and stroke. Treatments for hypertension are limited and there is a critical need to develop new therapies. The Renin Angiotensin Aldosterone System (RAAS) plays a key role in regulating blood pressure, and renin controls its rate-limiting step. In adults, renin is produced and stored by renal Juxtaglomerular (JG) cells. During sodium restriction and other pathophysiological stresses that require an increase in renin expression and release, the adult kidney increases the number of cells expressing renin, in a process known as JG cell expansion. JG cells formation mechanisms remain unclear. Our aim is to determine new regulators of renin and blood pressure control.

Methods:
In vivo:
JG cell expansion was induced by 10 days of low sodium diet (0.01% Na) and furosemide (0.1 mg/g body weight).
In vitro:
primary renal Mesenchymal Stromal Cells (MSC) were isolated from wild type mice and used until passage 5. MSC were differentiated into renin expressing cells by 7 days I&F (IBMX-100 uM and Forskolin-10 uM) treatment. Sox6 was down regulated in MSCs with lentivirus carrying vectors for Sox6 shRNA or controls scramble shRNA.

Results:
In vitro,
I&F induced renin expression in MSCs (Renin relative expression to gapdh 0.0153±0.005, n=3, P= 0.05, no renin expression in MSCs). Gene arrays comparing renal MSCs and JG cells identified Sox6 as a potential gene that controlled MSC differentiation.
In vitro
silencing of Sox6 by shRNA inhibited the differentiation of renal MSCs into renin producing cells (3.5 fold decrease compared to control shRNA, n= 4, P= 0.01). In a new transgenic mouse model, in which Sox6 is deleted specifically in renin expressing cells (Ren1d
Cre
/Sox6
fl/fl
), plasma renin concentration was not affected at baseline (0.3 vs W.T. 0.5 ug Ang I/ml/h, n=3, P>0.05). However, under conditions that promote JG cell expansion, Sox6 ablation halted the increase in the number of JG cells (8.75 fold decrease, n= 6 to 9, P= 0.001).

Conclusion:
Our data indicates that Sox6 plays a novel role in renal physiology; modulating renin expression during pathological conditions. These findings suggest that Sox6 may become a new target for blood pressure control.
Abstract 140: Endogenous Renin-angiotensin System Activation Causes Accelerated Cerebral Vascular Dysfunction in Mice Expressing Dominant-negative Mutations in PPARγ in Endothelium
Authors: Nair Anand R , Agbor Larry N , Mukohda Masashi , Hu Chunyan , Wu Jing , Sigmund Curt D
Published: March 2022

Abnormal activation of the renin-angiotensin system (RAS) has been implicated in cardiovascular (CV) disease. Whereas low salt diet (LSD) may be beneficial in salt-sensitive hypertension, it has been proposed to induce CV risk due to RAS activation. Peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-activated transcription factor which regulates the actions of angiotensin II (ANG) in the vasculature and promotes anti-oxidant pathways. We hypothesize that endothelial PPARγ plays a protective role in the vasculature in response to RAS activation. Transgenic mice specifically expressing dominant-negative (DN) mutations in PPARγ in the endothelium (E-DN) were fed a LSD and endothelial function was measured. Plasma renin and ANG were significantly increased in both non-transgenic (NT) and E-DN mice fed a LSD for 6 weeks compared with normal chow (Renin - NT: 39±7 vs 20±1 ng/ml; E-DN: 34±1 vs 16±4 ng/ml; AngII - NT: 257±54 vs 47±6 pg/ml; E-DN: 294±69 vs 63±14 pg/ml p<0.05, n=5). At baseline, vasorelaxation to acetylcholine (ACh) was not affected in E-DN compared to NT (basilar artery: 66±12 vs 64±4%; carotid artery: 93±4 vs 91±4%, n=5). Six weeks of LSD significantly impaired ACh-mediated relaxation in basilar artery of E-DN but not in NT (42±8 vs 74±5%, p<0.05, n=5). Unlike basilar artery, 6 weeks of LSD was not sufficient to induce vascular dysfunction in carotid artery of E-DN (carotid artery: 86±4 vs 92±3%, n=5). The endothelial dysfunction observed in the basilar artery of E-DN was attenuated upon in vitro incubation with tempol (improved from 29±5% to 55±7%, n=6). Further, administration of the AT1 receptor blocker, Losartan (0.6g/L drinking water) for the last 2 weeks of LSD blunted the endothelial dysfunction observed in the basilar artery of E-DN (improved from 24±2% to 64±9%, n=5). We conclude that interference with PPARγ in the endothelium produces endothelial dysfunction in the cerebral circulation in response to LSD-mediated activation of the endogenous RAS and this dysfunction is mediated, at least in part, through AT1 receptor activation and ROS signaling pathways. Moreover, our data suggest that the basilar artery and perhaps cerebral circulation is particularly sensitive to inhibition of PPARγ activity and activation of the RAS.
Abstract 144: Reduced Placental Regulator of G-Protein Signaling-2 (RGS2) and Preeclampsia
Authors: Perschbacher Katherine J , Deng Guorui , Sandgren Jeremy A , Carillo-Saenz Leslie , Santillan Donna A , Devor Eric J , Pierce Gary L , Santillan Mark K , Fisher Rory A , Gibson-Corley Katherine N , Grobe Justin L
Published: March 2022

The early mechanisms and genetic risk factors driving the pathogenesis of preeclampsia (PE), a cardiovascular disorder of pregnancy, remain largely unclear. Various hormone activators of Gα
q
second-messenger signaling pathways have been implicated in PE. Regulator of G-protein Signaling 2 (RGS2) acts as an endogenous terminator of Gα
q
signaling and previous studies identified a SNP (rs4606), which results in reduced RGS2 mRNA, as a risk factor for development of PE and its sequelae. We hypothesized reduced placental expression of RGS2 may precipitate the development of PE due to disinhibited Gα
q
signaling.
In silico
reanalysis of publically available dataset GSE75010 revealed RGS2 mRNA is reduced in placentas from pre-term PE pregnancies compared to normal pre-term pregnancies (con: 8.73 ± 0.07 n=35, PE: 8.37 ± 0.055 n=49, p<0.05). Using human placental tissue samples from the University of Iowa Maternal-Fetal Tissue Bank, we confirmed RGS2 mRNA is reduced in PE placentas (19% of control, p<0.05), despite a lack of correlation between the rs4606 SNP and PE. Additionally, in further reanalysis of other datasets, RGS2 mRNA is among the highest-expressed RGS member in normal human placenta, and appears to be selectively reduced in syncytio- and invasive cytotrophoblasts during PE (GSE93839, -26.3%, -23.3% of control). We next examined RGS2 expression in mouse placenta by FISH and found RGS2 mRNA colocalizes with markers of syncytiotrophoblast II (GCMA) and spongiotrophoblast (Tpbpα) layers. To test the effect of RGS2 loss during pregnancy, wildtype C57BL/6J female mice were mated with RGS2-deficient sires and developed diastolic hypertension, placental hypoxia by HIF1α ELISA (con 0.144±0.004, RGS2-KO 0.155±0.004 AU, p<0.05, n=5 each), and reduced placental PlGF mRNA (fold; con=1.0 n=7, RGS2-KO=0.23 n=12, p<0.05), compared to females mated with RGS2 littermate sires. These data support the concept that loss of RGS2 may contribute to the pathogenesis of PE rather than simply correlating with the disorder. Taken together, we have shown placental RGS2 is suppressed in PE, RGS2 is present in cytoplasm of specific layers of trophoblasts, and loss of feto-placental RGS2 is sufficient to cause placental hypoxia and maternal diastolic hypertension.
Abstract 147: Detrimental Cardiovascular Effects Associated With Use of >4 Drug Classes to Achieve Blood Pressure Control in SPRINT
Authors: McCallum Linsay , Llano Andrea , Aman Alisha , McClure John , Jardine Alan , Dominiczak Anna F , Chowienczyk Phil , Padmanabhan Sandosh
Published: March 2022

Background:
In the SPRINT trial,In SPRINT, achievement of target BP in the intensive arm required a higher number of drugs. Whilst intensive treatment of SBP was associated with an increased incidence of adverse events, it is unclear whether the use of multiple drug classes would result in adverse outcomes.

Methods:
The number of drug classes prescribed at randomisation and at 1,2,3,6,9,12 months were used to identify distinct trajectory groups in the standard and intensive arm using Latent Class Mixed Modelling. Data were available in 8,449 participants. Cox-PH models, adjusted for age, sex, SBP, prevalent CVD, prevalent CKD and number of drug classes at randomisation, were used to assess the association between drug class trajectories and pre-specified outcomes from SPRINT.

Results:
The SPRINT population classified into 6 groups (3 standard, 3 intensive) based on the trajectories of drug classes prescribed over the first year are shown in Panel A with corresponding SBP by drug class groups in Panel B.

Cox-PH model (reference group 4) showed group 5 (SBP 125 mmHg on >4 drug classes) had significantly higher risk of the primary outcome (HR 1.62 95% CI [1.12-2.04]; p 0.011), heart failure (HR 3.68 [1.95-6.94]; p <0.0005), CVD death (HR 4.34 [1.66-11.35]; p 0.003) and all-cause death (HR 1.75 [1.26-2.43]; p <0.0005) (Panel C).

Conclusions:
In SPRINT, treatment with >4 antihypertensive drug classes was associated with poor outcomes, specifically increased risk of death and heart failure, independent of blood pressure achieved in the first year, possibly related to the period of drug exposure. These results caution clinicians to assess need for multiple drugs and tighter blood pressure control.
Abstract 150: Target Organ Damage Occurs at SBP Levels Below the 95th Percentile in Adolescents: The SHIP AHOY Study
Authors: Urbina Elaine M , Lande Marc , Meyers Kevin , Samuels Joshua , Flynn Joseph
Published: March 2022

HTN leads to LV hypertrophy, increasing risk for CV events. The BP level at which LVH develops is not clear. We hypothesized that target organ damage (TOD: LVH; arterial stiffness; pulse wave velocity, PWV) occurs below the definition of HTN in youth (95
th
%ile of BP). We evaluated BP, anthropometrics, lab, LVM, and PWV in 180 adolescents (mean 15.8
+
1.5 yrs, 64% white, 57% male). Subjects were classified as normal (L=104, SBP<80
th
%ile), mid-risk (M=38, SBP 80-<90
th
%ile); or high-risk (H=38, SBP >=90
th
%ile) by mean of 6 aneroid SBPs according age, sex and height-specific pediatric cut-points. ANOVA was used to evaluate differences in CV risk factors and TOD across groups. General linear models were used to determine if SBP %ile was an independent predictor of TOD. Logistic regression was used to determine the SBP %ile most sensitive and specific for predicting LVH. Groups did not differ by age, sex, race or BMI %ile. Mean BP increased across groups (L=109/74, M=126/82, H=135/87 mmHg, p
<
0.0001). LVM, and PWV also increased (LVM L=31.5, M=34.7, H=35.3 g/m
2.7
; PWV L=4.8, M=5.2, H=5.3 m/sec, p
<
0.01). SBP %ile remained a significant determinant of TOD after adjusting for covariates including demographics, age, BMI, HR (LVM: SBP %ile β=0.04, R
2
0.32; PWV: SBP %ile β=0.01, R
2
0.29, all p
<
0.0001). The 90
th
%ile for SBP resulted in the best balance between false + (14%) and false - (13%) for LVH, however even at the 80
th
%ile, 8% of cases of LVH were missed and 16% (29 of 180) had LVH at SBP < 95
th
%ile. TOD occurs at levels lower than the pediatric definition of HTN even after controlling for BMI. Guidelines should consider TOD when setting cut-points for treatment.
Abstract P101: Degradation of Ang-(1-7) in Different Mouse Organs
Authors: Moore Andrew M , O’ Mahony Cliona , Walther Thomas
Published: March 2022

Introduction:
Ang-(1-7) has cardioprotective effects that serve to counter-regulate adverse effects of Ang II in the cardiovascular system. Angiotensin-(1-7) inhibits pressor, proliferative, and cell growth promoting effects of Ang II. Furthermore, it shows anti-fibrotic and anti-hypertrophic properties in preclinical models of myocardial infarction.

It is well accepted that Ang-(1-7) is primarily degraded to Ang-(1-5) by ACE in the cardiovascular system. However, we have preliminary results showing variations exist in Ang-(1-7) degradation pathways in various mouse organs. It is the aim of this study to quantify the metabolites in individual organs and to generate an organ-specific fingerprint of Ang-(1-7) truncation.

Methods:
Mouse organs were taken from male C57BL/6J mice and homogenates/membranes were prepared and measured for protein concentration. Membrane isolations were incubated with Ang-(1-7) and analyzed for peptide identification on an LCMS system.

Results:
Our results show that after 10 minutes Ang-(1-7) is degraded fastest in lung (1% [88108/6837249] of peptide remaining), followed by Kidney (8% [544423/6837249]), then liver (41% [2781701/6837249]), ventricle (83% [5699496/6837249]), and brain (86% [5868630/6837249]). Unsurprisingly, Ang-(1-5) was a major degradation product for the lung, kidney, and heart. However, we identified Ang-(1-4) as another major degradation product in lung and kidney. In contrast, the major degradation product of Ang-(1-7) in the brain and ventricle was Ang-(2-7). While Ang-(1-7) metabolism in testes yielded a unique angiotensin metabolite not observed in other tissues, Ang-(1-7) was not at all converted in atrium membranes.

Conclusions:
Ang-(1-7) degradation varies greatly in speed and metabolites between mouse organs. The necessity to update the relatively old canonical Ang-(1-7) degradation pathway is paramount for drug viability and design. By identifying the peptidases ultimately responsible for the metabolism of Ang-(1-7), its circulating concentration can be increased, thus improving the benefits of its cardiovascular protective effects.
Abstract P109: Bridging the Gap: Comparison of Hypertension Management Between Internal Medicine Residency and Faculty Practices
Authors: Bumrah Karandeep , Jan Naveed , Gill Taranjit , Kuchikulla Aishwarya , Pekez Marijeta , Fay Courtney , Thakur Kshitij
Published: March 2022

Introduction:
Studies have shown significant racial and geographical disparities in the management of hypertension. Not much has been studied about differences of hypertension management in a residency practice.

Aim:
Our study aims to compare hypertension management between an Internal Medicine residency and faculty practice.

Methods:
We retrospectively collected data from office electronic medical record. We included all patients with diagnosis of hypertension(ICD10: I10), between the age 45-60 years, seen between August 1, 2015 and August 1, 2016. Our exclusion criteria were patients with age <45 years or > 60 years, diabetes mellitus, and pregnant patients. A total of 600 charts were reviewed. Eighty one patients were excluded. We collected the following variable; age, gender race, number of office visits in one year, total number of medications used, smoking status, BMI and rate of physician blood pressure checks. The resident group had 259 patients and faculty group had 260 patients.

Results:
There was no significant difference in blood pressure control between two practices. The age and gender distribution between the two practices was similar but there was a significant difference in racial distribution. Residents saw more African American patients as compared to faculty. There were more smokers seen in resident practice. The rate of repeat physician blood pressure checks after medical assistant was similar. The two practices were in different parts of Delaware County with a significant difference in uninsured rate. The Residency practice was in a city with uninsured rate of 16.3% compared to 2.0% for the faculty practice.

Conclusion:
The study showed that there is no significant difference in the hypertension management between resident and faculty practices despite significant racial, financial and insurance coverage disparities.
Abstract P110: Low Intensity Stimulation of Aortic Baroreceptors as a Potential Therapeutic Alternative for Hypertension Treatment
Authors: Salman Ibrahim M , Ameer Omar Z , Sridhar Arun , Lewis Stephen J , Hsieh Yee-Hsee
Published: March 2022

Carotid baroreceptor stimulation has been clinically explored for antihypertensive benefits but aortic baroreceptor modulation remains untouched for clinical translation. Published studies use large current/voltage amplitudes (10V), longer pulse widths (2 ms) or ultra-high frequencies (70-100 Hz). These are energy inefficient neuromodulation methods. Our main goal was to identity optimal nerve stimulation parameters that would provide a sustained drop in mean arterial pressure (MAP) of ~30 mmHg. We stimulated aortic depressor nerve (ADN) in spontaneously hypertensive rats (SHR,
n
=4) at low ranges of frequencies, pulse amplitudes and pulse widths. Under urethane anesthesia, left ADN was stimulated for 20 seconds at varying frequencies (1, 2.5 and 5 Hz) and pulse amplitudes (0.2, 0.4 and 0.6 mA) at 0.1, 0.2 or 0.5 ms pulse width. A frequency-dependent depressor response was seen at all pulse amplitudes and widths used. Lower pulse amplitudes (0.2 mA) produced ~18 mmHg MAP drop at all pulse widths tested. Higher pulse amplitude (0.4 and 0.6 mA) produced similar drop in MAP of ~34 mmHg. The return to baseline values was relatively prolonged with higher charge injection with 32 seconds at 0.2 mA (0.1 or 0.2 ms at 5 Hz, maximum effect size: -18 mmHg) versus 42 seconds at 0.4 or 0.6 mA (0.1, 0.2 or 0.5 ms at 5 Hz, maximum effect size: -34 mmHg). There was no added benefit of pulse amplitudes beyond 0.4 mA. We conclude that low intensity stimulation is an effective alternate way to neuromodulation of the ADN. This will enable low energy consumption for neuromodulation. Future studies will study impact of these parameters in conscious SHR rats.
Abstract P119: Hypertension Trends in Florida Stroke Patients. The Florida Puerto Rico Collaboration to Reduce Stroke Disparities
Authors: Simonetto Marialaura , Shah Nirav H , Wang Kefeng , Ciliberti-Vargas Maria A , Gutierrez Carolina , Dong Chuanhui , Sanchez Jorge , Foster Dianne , Romano Jose’ G , Sacco Ralp L , Rundek Tatjana
Published: March 2022

Aim:
To describe hypertension prevalence (HTN) in a race diverse stroke registry and investigate associated presentation in patients admitted for acute ischemic stroke (AIS) and hemorrhagic stroke in Florida hospitals participating in the Florida Collaboration to Reduce Stroke Disparities (CReSD).

Background:
HTN affects about 30% of U.S. adults and this prevalence doubles among stroke survivors. HTN is a major risk factor for incident stoke and recurrent stroke. Quantifying the prevalence of HTN in stroke survivors is important to guide secondary stroke prevention.

Methods:
121,333 stroke cases were analyzed from 69 FL hospitals participating in the AHA Get With the Guidelines-Stroke Program and FL CReSD Stroke Registry. Hypertension was defined as systolic blood pressure >140mmHg. Demographics and CV risk factors were collected at admission. We investigated the differences in HTN prevalence between race groups: white (65%), black (20%) and Hispanic (15%) as well as between age groups: 18-60, 61-80 and >80 years old. Temporal trends of HTN prevalence were also analyzed from 2010 to 2016.

Results:
In our stroke population, mean age was 70±15 and 60,667 were women (50%). HTN prevalence was 65% (78,553/121,333). Patients with HTN were significantly older (mean age 72±14 vs. 67±16 in non-HTN patients) and presented significantly higher prevalence of other CV risk factors such as diabetes, hyperlipidemia and had more previous stroke/TIAs. Women had greater prevalence of HTN (66% vs. 64% in males) in all age groups. Greater HTN prevalence was in blacks (70%) compared to white (64%) and Hispanics (58%) in all age groups. Interestingly, a significantly higher prevalence of HTN was found in AIS compared to hemorrhagic stroke but a higher SBP was observed in hemorrhagic strokes compared to AIS. Prevalence of HTN decreased of 8% from 2010 to 2016. Largest decline was observed among women (9%) and blacks (13%).

Conclusions:
In our large Stroke Registry we observed higher prevalence of HTN in women, blacks and AIS. We also observe a decreasing trend over the past 7 years, especially among women and minorities (blacks and Hispanics). These findings provide an opportunity to design and implement interventions to reduce disparities in HTN and improve stroke outcome.
Abstract P123: Obesity and Alterations in Renal Function in Adolescents Born Preterm With Very Low Birth Weight
Authors: South Andrew M , Nixon Patricia A , Chappell Mark C , Diz Debra I , Russell Gregory B , Jensen Elizabeth T , Shaltout Hossam A , Washburn Lisa K
Published: March 2022

Background:
Survival of children born preterm has improved dramatically, but prematurity and low birth weight may increase the risk of renal disease. Children born preterm have a lower glomerular filtration rate (GFR) and higher blood pressure (BP) compared to term peers, but compounding risk factors for renal disease among children born preterm remain poorly characterized. Indeed, patient factors such as obesity may influence the development of kidney disease. Thus, we hypothesize that obesity is associated with decreased renal function in adolescents born preterm with very low birth weight.

Methods:
We measured systolic and diastolic BP, serum creatinine, and urine albumin at age 14 years in 124 adolescents born preterm with very low birth weight (mean birth weight 1056 g). We calculated the GFR by the Schwartz equation and the albumin-to-creatinine ratio (ACR) on morning urine samples. We used generalized linear models to estimate the association between obesity [body mass index (BMI) ≥95
th
%ile for age and sex,
n=
27] and renal function, adjusting for race, sex, maternal smoking during pregnancy, and birth weight z-score.

Results:
Obesity was associated with higher systolic BP (
p
=0.03). Compared to adolescents with BMI <95
th
%ile, those with obesity had lower GFR (
β
: -14.68 mL/min/1.73 m
2
, 95% CI -26.8 to -2.55). Adjustment for covariates attenuated this relationship (
β
: -10.05 mL/min/1.73 m
2
, -21.12 to 1.03). Adolescents with obesity had a higher serum creatinine, but this did not reach statistical significance (
β
: 0.05 mg/dL, -0.01 to 0.11). There was no difference in the ACR (
β
: -0.05, -0.13 to 0.02).

Conclusions:
Obese adolescents born preterm with very low birth weight exhibit higher systolic BP and lower GFR compared to those with BMI <95
th
%ile, though the statistical significance of the relationship with GFR weakened after adjustment for possible confounders. Importantly, sex was a significant confounder that may influence the relationship between GFR and obesity, as female adolescents had significantly lower GFR than male adolescents. While obesity should be avoided, other factors should be considered that may contribute to worse renal function in adolescents born preterm with very low birth weight.
Abstract P131: The Acute Effect of the Creatine Kinase Inhibitor Beta-GPA in Healthy Man (ABC-Trial): A Randomized Placebo Controlled First-in-human Trial
Authors: Karamat Fares A , Horjus Doortje L , Haan Yentl C , van Montfrans Gert A , Salomons Gajja S , Clark Joseph F , Brewster Lizzy M
Published: March 2022

Aim:
Increasing evidence indicates that the ATP-generating enzyme creatine kinase is involved in hypertension. Creatine kinase rapidly regenerates ATP from creatine phosphate and ADP. Recently, we showed that beta-guanidinopropionic acid (GPA), a kidney-synthesized creatine analogue and competitive inhibitor of creatine kinase, effectively and safely reduced blood pressure in spontaneously hypertensive rats. To further develop the substance as a potential blood pressure-lowering agent, we assessed the tolerability of a sub-therapeutic GPA dose in healthy men.

Methods:
In this active and placebo-controlled, triple-blind, single-center trial, we recruited 24 healthy men (18 to 50 years old, BMI 18.5 to 29.9 kg/m
2
) in the Netherlands. Participants were randomized (1:1:1) to one week daily oral administration of GPA 100 mg, creatine 5 gram, or matching placebo. The primary outcome was the tolerability of GPA, in an intent-to-treat analysis.

Results:
Twenty four randomized participants received the allocated intervention and 23 completed the study. One participant in the placebo arm dropped out for personal reasons. GPA was well tolerated, without serious or severe adverse events. No abnormalities were reported with GPA use in clinical safety parameters, including physical examination, laboratory studies, or 12-Lead ECG (Table1).

At day 8, mean plasma GPA was 213.88 (SE 0.07) in the GPA arm vs. 32.75 (0.00) nmol/L in the placebo arm, a mean difference of 181.13 (95% CI 26.53 to 335.72).

Conclusion:
In this first-in-human trial, low-dose GPA was safe and well-tolerated when used during 1 week in healthy men. Therefore, GPA is suitable for dose escalation trials
Abstract P144: Association Between Hypertension and Thyroid Abnormalities Among Hospitalized United States Patients: Data From National Inpatient Sample
Authors: Basnet Sijan , Dhital Rashmi , Tharu Biswaraj , Ghimire Sushil , Poudel Dilli R
Published: March 2022

Introduction:
Disorders of thyroid, hyperthyroidism and hypothyroidism, are established risk factors for hypertension. Comparison of these risk factors in terms of association has not been done.

Methods:
National Inpatient Sample database from 2009 - 2011 was utilized to explore relationship between hypertension and three categories of thyroid hormone levels (hyperthyroidism, hypothyroidism and euthyroidism). Multivariate logistic regressions were used to establish the association among all thyroid hormone level groups. We utilized STATA version 13.0 (College Station, TX) to perform the analyses.

Results:
Hypertension was more common in patients with hypothyroidism and hyperthyroidism in comparison to euthyroidism (Table 1). Multivariate analysis with logistic regression (controlled for age, sex, race, smoking, obesity, dyslipidemia, diabetes, Charlson comorbidity index) demonstrated that hypertension had a greater association with hyperthyroidism (OR 1.20; CI: 1.17 - 1.23) than hypothyroidism (OR 1.09; CI: 1.08 - 1.10).

Discussion:
T3 dilates peripheral arterioles and decreases systemic vascular resistance which stimulates renin secretion and increases effective arterial blood volume. Also, it increases heart rate and cardiac contractility. These mechanisms lead to increase in blood pressure. On the other hand, the mechanism with hypothyroidism is not fully recognized. It is thought to be secondary to increase in systemic vascular resistance. Through our study, we can conclude that the risk of hypertension is greater in patients with hyperthyroidism than with hypothyroidism.
Abstract P149: Maintenance of Optimal Health Behaviors Over 25 Years and Cumulative Blood Pressure Burden: Prospective Data From the Coronary Artery Risk Development in Young Adults Study
Authors: Booth John N , Allen Norrina B , Carson April P , Calhoun David , Shimbo Daichi , Shikany James M , Lewis Cora E , Redden David T , Muntner Paul
Published: March 2022

Introduction:
Healthy behaviors lower blood pressure (BP) in short-term randomized trials.

Hypothesis:
Maintaining healthy behaviors for 25 years will be associated with low cumulative BP burden.

Methods:
In 1985-86, the Coronary Artery Risk Development in Young Adults (CARDIA) study enrolled 5115 adults 18-30 years old. BP and health behaviors were measured at 8 exams over 25 years. Optimal health behaviors were body mass index (BMI) < 25 kg/m
2
, never smoking, moderate / vigorous physical activity ≥ 150 minutes weekly, no / moderate alcohol intake (women / men: 0-7 / 0-14 drinks weekly) and Dietary Approaches to Stop Hypertension (DASH) adherence score ≥ 15. Also, maintaining ≥ 4 optimal behaviors was assessed. Using Proc Traj in SAS, 4630 adults who had ≥ 1 optimal behavior at baseline and attended ≥ 3 exams were grouped by change in mid-BP with age. Odds ratios (OR) were calculated for each higher level of BP burden associated with maintaining versus not maintaining optimal behaviors at all exams.

Results:
Those who did versus did not maintain optimal BMI were less likely to have moderate-stable, elevated-stable or moderate / elevated-increasing versus low-stable BP burden (
Figure, Panel A
). There was a non-statistically significant lower OR for the highest versus low-stable BP burden in adults who maintained optimal smoking and alcohol intake (
Figure, Panels B-C
). Optimal physical activity and DASH diet were not associated with mid-BP burden (
Figure, Panels D-E
). The OR (95% CI) for moderate / elevated-increasing versus low-stable BP burden in those maintaining ≥ 4 optimal behaviors was 0.73 (0.39 - 1.38).

Conclusion:
Maintaining optimal BMI into middle age preserves low BP burden.
Abstract P157: Genetic Stratification of Cardiovascular Risk in Patients With Arterial Hypertension
Authors: Bondar Vadym N , Chernyshova Kateryna , Kobeleva Helen , Tbileli Viktoria , Maznichenko Yegor
Published: March 2022

The purpose of the study was to form a model of genetic stratification of cardiovascular risk (CVR) based on the evaluation of polymorphisms of candidate genes and total gene modification index (GMI), to compare this model with existing clinical stratification scores of CVR and to evaluate the possibility of its use with prognostic purpose in patients with arterial hypertension (AH) in Ukrainian population.

Materials and Methods:
240 patients with AH were examined and stratificated depend from prognostic CVR according to ESC 2013. The patients were divided into 4 groups: with low, moderate, high or very high CVR. Then we performed the analysis of polymorphisms of the following candidate genes by PCR: ADD1:1378, AGT:704, AGT: 521, AGTR1:1166, AGTR2: 1675,CYP11B2:-344, GNB3:825, NOS3:-786, NOS3:894. We formed GMI, in which the proportion of “pathological” homozygous polymorphism of one gene was 1.5 points, the heterozygous polymorphism - 1 point, “normal” genotype - 0 points. Then points were summed up and divided by maximum possible amount and GMI was formed as proportion of the “pathological” genotypes, expressed as a percentage. We offered the genetic stratification, in which GMI from 0 to 20% was considered as low genetic risk, from 21 to 40 % - moderate risk, from 41 to 70% - high risk, from 71 to 100% - very high risk. The statistical analysis of correlations was made between the traditional and genetic stratification scores.

Results:
As a result of traditional stratification of risk factors in group with low CVR were 24 patients, while in 75% of patients was similar low genetic risk (GR) according to the GMI (r=0,72, p<0,01). In group with moderate CVR were 96 patients, of which 75% had moderate GR (r=0,71, p<0,01). In group with high CVR were 72 patients, 72% of them had high GR (r=0,71, p<0,01). In group with very high CVR were 48 patients, 67% of them had same very high GR (r=0,70, p<0,05). Thus, proposed genetic stratification risk score based on evaluation of proportion of “pathological” genotypes of candidate genes, has a significantly high correlation with traditional stratification score of CVR and can be used with prognostic purpose in patients with AH. Genetic stratification risk score can have obvious benefits for the purposes of primary prevention of AH.
Abstract P173: Target Blood Pressure in Elderly Hypertensive Patients: A Korean National Health Insurance Service Health Examinee Cohort Study
Authors: Seo Jiwon , Park Sungha , Lee Chan Joo , Hwang Jinseub
Published: March 2022

Background:
We aimed to investigate the benefits of strict blood pressure control and determine the optimal blood pressure in elderly hypertensive subjects.

Methods:
This study used the National Health Insurance Service Health examinee Sample Cohort. We selected subjects who were over the age of 60 years and who had received a newly diagnosis of hypertension (Korean Classification of Disease [KCD] codes I10–I13) from 2003 to 2006. Subjects who had previous major cardiovascular (CV) events, such as heart failure, ischemic heart disease, stroke, or end stage renal disease (ESRD) were excluded. The remaining 25,858 individuals were divided into three groups; 1) mean systolic blood pressure (SBP) < 130mmHg (N = 7,494), 2) mean SBP 130 to 140 mmHg (N = 9,272), 3) mean SBP above 140mmHg (N = 9,092). The primary outcome of the study was to compare all-cause mortality and CV mortality in each group.

Results:
Compared to mean SBP ≥140 mmHg group, mean SBP 130 to 140 mmHg group had significantly lower rate of all-cause mortality (HR=0.63, 95% CI= 0.58-0.69, p<0.001) and CV mortality (HR=0.58, 95% CI= 0.48-0.69, p<0.001). The diastolic blood pressure (DBP) between 80 to 90 mmHg group also had lower risk of all-cause death (HR=0.51, 95% CI= 0.47-0.56, p<0.001) and CV death (HR=0.44, 95% CI= 0.37-0.53, p<0.001) in comparison with DBP ≥90 mmHg group. However, the SBP below 130 mmHg subjects and the DBP below 80 mmHg subjects did not have significant lower rate of all-cause and CV mortality compared to SBP 130 to 140 mmHg and DBP 80 to 90mmHg subjects, respectively. In subgroup analysis, mean SBP <120 mmHg subjects were associated with higher risk of all-cause death (HR=1.47, 95% CI= 1.27-1.72, p<0.001) and CV death (HR=1.57, 95% CI= 1.15-2.14, p=0.004) than SBP 130 to 140 mmHg subjects.

Conclusion:
Mean SBP between 130 to 140 mmHg and mean DBP below 90 mmHg for elderly hypertensives without previous major CV disease was beneficial in reducing all-cause and CV mortality. However, mean SBP below 120mmHg was associated with a raised risk of all-cause mortality and CV mortality.
Abstract P176: A New Function for Adipocytes: Norepinephrine Storage
Authors: Ahmad Maleeha , Ayala-Lopez Nadia , Darios Emma , Watts Stephanie W
Published: March 2022

Activation of the sympathetic nervous system, and the subsequent release of the neurotransmitter norepinephrine (NE), contracts blood vessels and increases blood pressure, a mechanism altered in obesity-related hypertension. Perivascular adipose tissue (PVAT) is a functional reservoir for catecholamines, including NE, and PVAT adipocytes have plasma membrane transporters that can transport NE, pointing to similarities with the neuronal handling of NE. Thus, we hypothesize that PVAT adipocytes store NE, and use the vesicular monoamine transporter (VMAT) to do so, similar to sympathetic neurons. High-pressure liquid chromatography showed NE present in normal male Sprague Dawley rat superior mesenteric artery (SPVAT; 503.60 ± 34.70 ng mg tissue
-1
) and mesenteric (MPVAT; 148.20 ± 15.00 ng mg tissue
-1
) PVATs (N=6). Using immunofluorescence, we tested for VMAT1 and VMAT2 in these PVATs (N=6). Both transporters were present surrounding the lipid of the adipocytes. We developed a novel protocol imaging live primary rat MPVAT adipocytes to capture real-time uptake of Mini202, a fluorescent VMAT probe functioning as a false neurotransmitter (N=4). Cells stained with 500 μM Mini202 (Corrected Total Cell Fluorescence x 10^6 = 9.29 ± 0.88). Addition of 100 μM Rose Bengal, a potent VMAT inhibitor, eliminated Mini202 signal (CTCF x 10^6= -1.72 ± 0.30. Negative because Mini202 background brighter than abolished signal). These data support a new function of adipocytes in storing catecholamines. Understanding NE uptake and storage in PVAT is crucial for research on obesity-related hypertension and is important considering the growing prevalence of obesity and cardiovascular disease.
Abstract P177: Intermittent Hypoxia Attenuates Corticotropin-Releasing Hormone Receptor 2 (CRHR2) mRNA and CRHR2-Mediated Calcium Influx in Neurons in the Nucleus of the Solitary Tract
Authors: Wang Lei , Mifflin Steve
Published: March 2022

Studies have suggested that corticotropin-releasing hormone (CRH) originating within the hypothalamic paraventricular nucleus (PVN) acts in the nucleus of the solitary tract (NTS) to regulate sympathetic and cardiovascular functions, but the anatomical distributions and cellular actions of CRH receptors (CRHRs) in the NTS are not fully understood. We conducted
in situ
hybridization for CRH type 1 and type 2 receptors (CRHR1 and CRHR2) in Crl:CD(SD) rats and present mRNA levels as the total pixel gray values of positive staining calculated by ImageJ. The mRNA level of CRHR2 was significantly higher than CRHR1 (1.97 ± 0.1 x 10
7
, n=4 vs. 4.56 ± 0.92 x 10
6
, n=4; p < 0.0001) in the caudal NTS (13.68 mm - 14.76 mm caudal to bregma). We then investigated how the NTS CRHRs and CRHRs signaling pathways were influenced by 7 days exposure to intermittent hypoxia (IH), a model of the arterial hypoxemias that occur during sleep apnea. IH significantly decreased CRHR2 mRNA level in caudal NTS by 34 ± 14% (1.97 ± 0.1 x 10
7
, n=4 vs. 1.3 ± 0.22 x 10
7
, n=3; P < 0.05) but did not affect CRHR1 mRNA level. To investigate the cellular actions of CRHRs in the NTS, we performed calcium imaging on NTS slice preparations using Fura-2-acetoxymethyl ester and present intracellular calcium levels as the ratio of fluorescent intensity excited by 340nm vs. 380nm. CRH induced a transient increase of intracellular calcium level (n=19) that was abolished by the voltage-dependent calcium channel blocker nifedipine. Calcium influx was attenuated by the CRHR2 antagonist K41498 (0.06 ± 0.006, n=19 vs. 0.041 ± 0.004, n=11; P < 0.01) but not by CRHR1 antagonist NBI-35965 (n=5). The CRHR2 agonist Urocortin-II induced calcium influx (0.05 ± 0.005, n=9) but not the CRHR1 agonist Stressin-I. IH also attenuated the CRH-induced calcium influx in the NTS (0.06 ± 0.006, n=19 vs. 0.04 ± 0.004, n=19; P < 0.01). Collectively, these results demonstrate that CRHR2 mediates calcium influx in NTS neurons and IH diminishes this effect by down-regulating CRHR2.
Abstract P182: Chronic Central Melanocortin 4 Receptor Blockade Does Not Prevent Cardiac Dysfunction After Myocardial Infarction in Rats
Authors: Gava Fabio , da Silva Alexandre A , do Carmo Jussara M
Published: March 2022

Progression of myocardial infarction (MI) to heart failure may be exacerbated by excessive activation of the sympathetic nervous system (SNS). We previously showed that the central nervous system (CNS) melanocortin system plays a key role in regulating SNS activity and blood pressure (BP) in several different conditions, including hypertension and obesity. Therefore, we tested whether melanocortin-4 receptor (MC4R) blockade protects against cardiac dysfunction associated with MI in rats. Male Sprague-Dawley rats at 12 weeks of age were implanted with BP telemetry transmitters and an intracerebroventricular (ICV) cannula was inserted into the lateral ventricle. After 10 days of recovery, food intake, mean arterial pressure (MAP) and heart rate (HR) were measured 24-hrs/day by telemetry and cardiac function was assessed by echocardiography (VEVO 2100
@
). After stable baseline measurements for 4 days, the left coronary artery was permanently ligated and vehicle (n=5) or the MC4R antagonist (SHU-9119, 1 nmol/h, n=7) was infused ICV via osmotic minipump for 28 consecutive days. Chronic MC4R antagonism significantly increased food intake and body weight (25±1 to 37±4 g/day and 365±4 to 497±10 g) compared to vehicle treatment (24±1 to 20±1 g/day and 372±6 to 417±5 g). Chronic SHU-9119 infusion did not alter MAP (108±1 to 105±2 mmHg) whereas MAP was significantly reduced in vehicle-treated rats with MI (104±1 to 97±2 mmHg). However, HR decreased more in SHU-9119-treated rats (~-70 bpm) than in vehicle group (~-42 bpm). Compared to vehicle, SHU-9119 infusion for 4 weeks did not prevent cardiac dysfunction caused by MI as evidenced by low cardiac radial strain (40±1 to 18±3 vs. 44±2 to 23±5 %), cardiac output (106±7 to 68±4 vs. 114±5 to 86±8 ml/min) and ejection fraction (71±2 to 33±2 vs. 71±2 to 38±4 %). These results suggest that chronic central MC4R inhibition does not attenuate the progression to heart failure after MI in rats. (NHLBI-PO1HL51971, NIGMS- P20GM104357)
Abstract P188: Nephron-wide Deletion of Nos3 Impairs Salt Excretion and Causes Hypertension
Authors: Gao Yang , Stuart Deborah , Takahishi Takamune , Kohan Donald E
Published: March 2022

In vitro studies have suggested that nephron nitric oxide synthase 3 (NOS3) plays a role in the regulation of urinary Na
+
excretion (UNaV) and potentially contributes to blood pressure (BP) control. To assess whether NOS3 is indeed involved in the physiological regulation of UNaV and BP, mice with doxycycline-inducible nephron-wide deletion of NOS3 were generated. These mice were homozygous for loxP-flanked exons 9-12 of the NOS3 gene (contains the calmodulin binding site) and hemizygous for Pax8-rtTA and LC-1 transgenes (Pax8 promoter-rtTA confers nephron-specific targeting and LC-1 transgene contains doxycycline/rtTA-inducible Cre recombinase). Mice were treated with either vehicle (controls) or doxycycline (knockouts, KO) at 1 month of age for 12 days and studied at ~3 months of age. Nephron-specific NOS3 KO mice had renal-specific NOS3 gene recombination and reduced mRNA levels in microdissected nephron segments. Renal vascular NOS3 mRNA levels were markedly increased in KO mice, presumably as a compensatory response to nephron NOS3 KO. KO mice had modestly increased mean arterial pressure (100 ± 2 mmHg in controls and 103 ± 1 mmHg in KO, N=6, p<0.05) on a normal (0.3% Na
+
) salt diet that increased further during high (3.2% Na
+
) salt intake (103 ± 2 mmHg in controls and 118 ± 3 mmHg in KO, N=6, p<0.05). KO mice had reduced daily UNaV and greater cumulative Na
+
retention compared to controls over the 7 days of high salt feeding. PRC tended to be lower in KO mice on a high salt diet compared to controls (85.8 ± 13.5 ng/ml in controls and 60.1 ± 10.3 ng/ml in KO, N=12, p<0.07). Control mice excreted most of an acute I.P. salt load by 4 hr post-load, while KO mice excreted the acute salt load between 5-7 hr after loading. Furosemide, but not hydrochlorothiazide, abolished the differences in UNaV between control and control mice following an acute salt load. No sex-dependent differences in UNaV or BP were observed. In summary, these findings indicate that nephron NOS3 is involved in acute and chronic control of renal Na
+
excretion and BP during high salt intake. Taken together with previous studies showing that collecting duct-specific KO of NOS3 does not alter UNaV or BP, our data suggest that thick ascending limb is at least partly involved – further mechanistic studies are ongoing.
Abstract P189: Endothelial Cullin3 Mutation Causes Vascular Dysfunction, Arterial Stiffening, and Hypertension
Authors: Wu Jing , Agbor Larry N , Fang Shi , Hu Chunyan , Lu Ko-Ting , Liu Xuebo , Mukohda Masashi , Nair Anand R , Sigmund Curt D
Published: March 2022

Mutations in CULLIN3 gene (causing in-frame deletion of exon 9) cause hypertension in humans. The hypertension phenotype is unlikely to be driven by renal tubular mechanisms, as kidney-specific deletion of Cullin3 (Cul3) in mice results in hypotension, not hypertension. We have recently shown that smooth muscle expression of Cul3Δ9 causes vascular dysfunction and elevation of blood pressure (BP) via augmented RhoA/Rho-kinase signaling, strongly supporting a vascular role of Cul3 in BP regulation. To test the importance of endothelial Cul3
in vivo
, we bred the conditionally activatable Cul3α9 mice with Tek-CRE
ERT2
mice specifically expressing tamoxifen-inducible Cre-recombinase in the endothelium. The resultant mice (E-Cul3α9) exhibited impaired endothelial-dependent relaxation in the basilar artery (maximal relaxation in response to 30 μM acetylcholine, 45% vs 85% in control mice) and carotid artery. No difference in smooth muscle function was observed. Moreover, E-Cul3α9 mice exhibited nocturnal hypertension as determined by radiotelemetry (night time peak BP, 141±3 mmHg vs 122±3 mmHg). However no difference was seen in daytime pressure. E-Cul3α9 mice also exhibited arterial stiffening as indicated by elevated pulse wave velocity (3.7±0.3 m/s vs 2.7±0.1 m/s). To determine the molecular mechanism of endothelial dysfunction, primary aortic endothelial cells were isolated from mice carrying the inducible Cul3α9 construct and Cul3α9 expression was robustly induced by adenovirus carrying Cre recombinase gene
in vitro
. Cul3α9 acted in a dominant negative manner by interfering with expression and function of wild type Cul3, leading to impaired turnover of a Cul3 substrate protein phosphatase 2A, marked reduction in phosphorylated eNOS, and decreased nitric oxide production. Treatment with a selective PP2A inhibitor Okadaic Acid (1 nM) rescued Cul3α9-induced impairment of eNOS activity. These data define a novel pathway involving Cullin-3/PP2A/phospho-eNOS in the endothelium. Selective endothelial expression of Cul3α9 partially phenocopies the hypertension observed in Cul3α9 patients, suggesting that mutations in Cullin-3 cause human hypertension in part through a vascular mechanism characterized by endothelial dysfunction.