bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 113: Female Protection From Arterial Stiffness Diminishes With G Protein-Coupled Estrogen Receptor Deletion or Angiotensin II Hypertension
Authors: Ogola Benard O , Abshire Caleb M , Clark Gabrielle L , Lawrence Dylan J , Zimmerman Margaret A , Bayer Carolyn L , Miller Kristin S , Lindsey Sarah H
Published: December 2018

Arterial stiffness independently predicts cardiovascular mortality, coronary events, and stroke in hypertensive subjects and is exacerbated in women following menopause. Previously, our laboratory indicated that G protein-coupled estrogen receptor (GPER) plays a protective role in the vasculature. Therefore, the current study assessed the impact of sex and GPER on arterial stiffening in control and hypertensive conditions. We hypothesized that genetic deletion of GPER attenuates sex differences in arterial stiffness. Male and female wildtype (wt) and global GPER knockout (ko) mice (n=46) were used between 16-21 weeks of age. Angiotensin II (Ang II) infusion (700 ng/kg/day for two weeks) was used to induce hypertension, and systolic blood pressure (SBP) was measured using tail cuff plethysmography. Local pulse wave velocity (PWV) within the carotid artery was obtained via high frequency ultrasound in both color Doppler and M-mode. Statistical analysis was performed using two-way ANOVA with Sidak’s multiple comparisons test. Baseline SBP was significantly lower in females (P=0.035) but was not impacted by genotype (P=0.78). Baseline PWV was significantly higher in male versus female wt mice (1.29 vs. 0.804 m/s, P=0.003) but was not different in ko mice (1.25 vs. 1.04 m/s, P=0.22). Ang II infusion significantly increased SBP (P<0.001) and PWV (P<0.001) in all groups, removing any impact of sex or genotype. In addition, significant correlations were found between Doppler and M-mode methods for obtaining carotid PWV (r=0.67, P<0.001) and between PWV and
ex vivo
carotid wall thickness (r=0.70, P=0.004). In contrast, SBP did not correlate with PWV (P=0.77) or carotid wall thickness (P=0.68). In conclusion, we found that GPER deletion did not impact blood pressure either in normotensive or hypertensive conditions. While arteries from female wt mice were less stiff at baseline, genetic deletion of GPER or Ang II infusion removed this protection independent of blood pressure. Moreover, we found that local carotid PWV provides information on vascular status that could not be obtained via blood pressure. This data indicates that GPER plays an important role in female vascular physiology that is absent in pathological conditions.
Abstract 120: Long-Term Stability of the Masked Hypertension Phenotype and Responsiveness of Masked Hypertension to Antihypertensive Treatment: Findings From the Masked Hypertension Study
Authors: Kronish Ian M , Young Justin , Shimbo Daichi , Schwartz Joseph E
Published: December 2018

Background:
Prior studies have assessed the short-term reproducibility of the masked hypertension (MHT) phenotype. Less is known about the stability of MHT over time or its responsiveness to BP medication.

Methods:
We assessed BP phenotypes in 441 untreated subjects with a screening BP<160/105mmHg using office BP and 24-hr ambulatory BP monitoring on 2 occasions, 6 years apart. MHT was defined as office BP<140/90mmHg and awake ambulatory BP≥135/85mmHg. Sustained hypertension at follow-up was defined as office BP≥140/90mmHg and ambulatory BP≥135/85mmHg or treatment with BP medication. Left ventricular mass (LVM) was assessed by 2D-echo.

Results:
Of subjects with MHT at baseline, 41%(24/59) continued to have MHT at 6 years, 44%(26/59) developed sustained hypertension, and 15%(9/59) became normotensive (
Table
). Of subjects with baseline office SBP 120-139mmHg, there was a trend toward a greater increase in LVM over 6 years in those with versus without MHT (change in LVM +25.2±37.5g vs +15.7±27.8g, p=0.25). Of subjects with MHT at baseline, those on BP treatment at 6 years had a decrease in ambulatory awake SBP compared to baseline whereas untreated subjects had an increase in ambulatory awake SBP (-5.4±7.2mmHg vs +7.2±8.0mmHg; p<0.001). MHT subjects who were treated also had a smaller increase in LVM (+21.5±41.6g vs +30.4±32.3g; p=0.58).

Conclusion:
Approximately half of MHT subjects progressed to sustained hypertension over 6 years, supporting the hypothesis that MHT is an intermediary phenotype on the way to sustained hypertension. Treatment with BP medication was associated with lower ambulatory BP, though randomized trials are needed to confirm efficacy and safety.
Abstract 127: Axl
+
Siglec6
+
Dendritic Cells: the Role of Salt, Stretch, and Hypertension
Authors: Van Beusecum Justin P , Barbaro Natalia R , Loperena Roxana , Harrison David G
Published: December 2018

We have shown that monocyte-derived dendritic cells (DCs) are activated in hypertension to produce large amounts of cytokines and to activate T cells. DCs from hypertensive mice can convey hypertension when adoptively transferred to recipients. Single cell sequencing has recently identified a novel subset of DCs in humans that express Axl and Sigelc6
+
(AS DCs). These cells have been reported to potently drive T cell proliferation and to produce large amounts of IL-8 and IL12. The role of AS DCs in hypertension remains unknown. We isolated total peripheral blood mononuclear cells (PBMCs) from normotensive (n=23) and hypertensive (n=12) patients and assessed DC populations, including AS DCs, using flow cytometry. We found a significant increase in the AS DCs in hypertensive compared to normotensive patients (297 ± 73 vs. 108 ± 26/ml; P=0.0304). In contrast, there were no differences in CD1c
+
DCs (3398 ± 776 vs. 5245 ± 122/ml) or CD141
+
DCs (164 ± 20 vs. 218 ± 49/ml) between normotensive and hypertensive subjects. To investigate the mechanism by which AS DCs are formed in hypertension, we used two
in vitro
hypertensive stimuli: exposure to salt and hypertensive stretch of adjacent human endothelial cells. Human PBMCs were cultured in either normal NaCl (NS, 150 mM) or high NaCl (HS, 190 mM) for 48 hours. Flow cytometry indicated a striking increase in AS DCs by exposure to HS compared to NS (516 ± 181 vs 201 ± 57/ml) and this was prevented by co-treatment of cells with the salt-sensing Serum Glucocorticoid Kinase 1 inhibitor GSK650394. As a second approach, we co-cultured human aortic endothelial cells (HAECs) with PBMCs from normotensive donors and exposed the HAEC monolayer to either normal (5%) or hypertensive cyclical stretch (10%) for 24 hours. Co-culture of PBMCs with HAECs exposed to 10% stretch doubled AS DCs as compared to PBMCs cultured with HAECs undergoing 5% stretch (1.4 ± 0.5 vs 0.7 ± 0.3%; P=0.0217). These data show that AS DC population are increased in hypertensive patients and that known hypertensive stimuli
in vitro
promote formation of AS DCs. Thus, AS DCs seem to be an important immune cell subset in human hypertension and might be a novel therapeutic target for this disease.
Abstract 130: ATP Release Drives the Immune Responses Associated With Hypertension
Authors: Zhao Tuantuan , Zhu Qian , Li Yu , Liu Xiaoli , Shi Peng , Bernstein Kenneth E , Shen Xiao Z
Published: December 2018

Inflammation is critical in progression of hypertension. However, how an elevated blood pressure (BP) initiates inflammation is unknown, as are the precise effects of high BP on the immune responses. To study this, we first challenged mice with antigen ovalbumin (OVA). Two-fold more OVA-specific CD8
+
T cells were present in the blood (2.7 ± 0.23% vs. 1.2 ± 0.47%) and spleen (2.62 ± 0.31% vs. 1.31 ± 0.17%) of angiotensin (Ang) II induced hypertensive mice as compared to those of normotensive controls. To address whether the over-activation of T cell-mediated immune responses is pathogenic, two models of autoimmune disease were studied. RIP-mOVA is a transgenic mouse line that expresses OVA in pancreatic islet β cells. When OVA-specific OT-I T cells were infused into Rip-mOVA mice, the animals with hypertension induced by either Ang II or L-NAME developed more severe diabetes (blood glucose (mg/dl): Ang II 331, L-NAME 315
vs.
Control 168). Concanavalin A-induced hepatitis was also significantly worsened by hypertension as compared to the pathology observed in normotensive mice. After examining the characteristics of T cells and antigen presenting cells (APCs), we found that the most distinguishable difference in hypertensive mice was the upregulation of CD86 on APCs. Blocking CD86 by antibody completely abrogated the elevated immune responses in hypertensive mice. To understand what causes CD86 upregulation in APCs of hypertensive mice, we studied damage-associated molecular patterns and found that plasma ATP levels rose as early as 3 days after the induction of hypertension and reached from about 1μM of baseline to a peak level of 3 μM after 2 weeks of hypertension, which exactly parallels the kinetics of CD86 elevation on APCs. Hydrolyzing ATP or blocking its P2X
7
receptor normalized APC CD86 expression and eliminated hypertension-induced T cell over-activation. Further, untreated human hypertensive patients have substantially elevated plasma ATP levels (2.21 ± 0.99 μM,
n
= 27) compared to treated hypertensive patients (0.94 ± 0.34 μM,
n
= 17) or normotensive controls (0.63 ± 0.38 μM,
n
=30). A linear trend was observed between ATP levels and BP among all subjects. These studies indicate ATP is critical in initiating hypertension-associated inflammation.
Abstract 132: Obesity-Related Hypertension Develops Through Splenic Sympathetic Overactivity and is Mediated by Immune-Modulating Functions of Placental Growth Factor
Authors: Carnevale Daniela , Lori Andrea , Carnevale Lorenzo , Perrotta Marialuisa , Pallante Fabio , Carnevale Raimondo , Iodice Daniele , Lembo Giuseppe
Published: December 2018

Obesity-related hypertension (HTN) is an epidemic health problem and a major risk factor for the development of cardiovascular disease. A consistent amount of research on the pathophysiological basis of obesity has implicated a crucial role of sympathetic overdrive. Interestingly, an overactivation of the sympathetic nervous system (SNS) accompanies HTN as well. Recent data highlighted that increased SNS activation in HTN is important in modulating immune responses, besides controlling typical cardiovascular functions. Whether neuroimmune mechanisms are relevant in obesity-induced HTN is still unknown. To test this hypothesis we subjected 6 week-old C57Bl/6J mice to high fat diet (HFD), as compared to low fat diet (LFD) and monitored blood pressure (BP), which started to rise after 2 months and steadily increased up to 4 months. We measured circulating noradrenalin, finding it significantly elevated 2 months after HFD. To gain insights in the potential SNS modulation of immunity, we measured by microneurography SNS activation on the splenic nerve. Firing frequency (FF, spikes in 10') of splenic nerve was increased in C57Bl/6J mice on HFD (FF:432±81) as compared to LFD (FF:86±10, p<0.01). Then, we surgically removed splenic innervation by left celiac ganglionectomy (CGX) and fed mice with HFD for 4 months. Despite CGX-mice become obese similarly to sham, as shown by body weight and microCT-measured fat pad, they were protected from HTN (SBP
mmHg
=CGX:105±4; sham:125±5, p<0.001), suggesting that the splenic sympathetic overdrive influences BP responses but not metabolic alterations. To look for molecular determinants, we analyzed the expression of Placental Growth Factor (PlGF), previously identified as a neuroimmune mediator, and found it significantly increased in the spleen upon HFD, but only with intact SNS innervation, since CGX-mice did not increase it. In the end, PlGF KO mice subjected to HFD, although becoming obese as much as WT, were protected from HTN (SBP
mmHg
=PlGF KO:103±4; WT:123±6, p<0.001). Interestingly, both CGX and PlGF KO mice displayed a reduced egression of activated T cells from the spleen upon HFD feeding, suggesting that the protection observed could be related to reduced infiltration of activated lymphocytes in target organs.
Abstract P105: An Exploration Of The Relationship Between Endothelial Function, Blood Pressure And Anthropometric Measurements In 6-8 Year Old Rural Versus Urban Children In The Eastern Cape Province Of South Africa.
Authors: Letwalo Prescilla B , Matjuda Edna N , Sewani-Rusike Constance R , Nkeh-Chungag Benedicta N
Published: December 2018

Arterial stiffness is an independent predictor of cardiovascular disease. Although mostly detected in adults evidence in children is conflicting. Many more children are being diagnosed with hypertension indicating that these children might have some level of endothelial dysfunction. The current study set out to investigate the relationship between endothelial function as measured by the Vicorder and anthropometric measurements as well as blood pressure in 6-8 year old children. A total of 202 children were recruited from a rural and an urban community were recruited into a cross sectional study between March and November 2017. Anthropometry was performed followed by measurement of blood pressure parameters and flow mediated slowing (FMS) using the Vicorder. Urine samples were collected for creatinine/albumin ratio. Body mass index (BMI), systolic and diastolic blood pressure (SBP, DBP) were converted to percentiles for age, height and sex. Stata ® was used for all data analysis. Mean PWV and FMS% were 5.0 m/s and 25.7% respectively. PWV and heart rate (HR) were different by sex and location (p<0.01 and p<0.0001 respectively) while FMS% was similar in all groups. FMS% correlated negatively with most anthropometric and blood pressure variables. PWV was significantly higher in hypertensive children (5.9 vs 4.7; p<0.05) and correlated modestly with Neck circumference (r= 0.46; p< 0.05), SBP (r= 0.35; p<0.05), DBP (r=0.046; p< 0.05) while in rural males it correlated with SBP and DBP (r=0.50, r= 0.44; p, 0.05) and it urban males it correlated with creatinine/albumin ratio (0.52; p< 0.05). There was no correlation in urban females. PWV was higher in 6-8 year old children who had either hypertension or pre-hypertension and was predicted by DBP in rural girls. Correlation of PVW with creatinine/albumin ration may be indicative of compromised endothelial function.
Abstract P106: Association Of Pulse Wave Velocity With Hypertension And Anthropometric Measurements In 6-8 Years Old Children In Mthatha, South Africa
Authors: Matjuda Edna N , Letswalo Prescilla B , Sewani-Rusike Constance R , Nkeh-Chungag Benedicta N
Published: December 2018

Hypertension is becoming a major health problem in children worldwide. There is evidence suggesting a complex association between hypertension, endothelial function and other cardiovascular disease risk factors in the adult population. Very few studies have investigated the relationship between hypertension and endothelial function in sub-Saharan children. The aim of this study was to explore the relationship between blood pressure parameters and pulse wave velocity (PWV) in 6-8 years old children in the Eastern Cape of South Africa. A cross-sectional study of 202 children (103 girls and 99 boys) aged 6-8 years old was conducted between March and November 2017. General anthropometric measurements were measured and blood pressure measurements were recorded. Blood pressure measurements were converted to blood pressure percentiles for height, age and sex. Flow mediated slowing was used to measure endothelial function. The prevalence of hypertension and prehypertension was higher in girls compared to boys (7.9% and 28.7% vs 7.1% and 20.2% respectively). Systolic and diastolic pressure (SBP, DBP) and pulse pressures were similar in boys and girls. No sex related difference in PWV was noted thought the strength of correlation was different. PWV correlated modestly with age, SBP, DBP and mean arterial BP in females (r= 0.24, 0.30, 0.40, 0.49 p<0.05) and in males (r= 0.38, 0.36, 0.34, 0.39; p<0.05). Blood pressure and PWV correlated modestly with anthropometric measurements in females but not in males. This study in a sub-Saharan African population of 6-8 year old children showed that even though there was no sex difference in blood pressure, the prevalence of hypertension and pre-hypertension were different. PWV correlated differently with blood pressure parameters and anthropometric measurements in males and females.
Abstract P110: Renal Angiotensin Generation Depends on Hepatic Angiotensinogen: Evidence From a Preclinical Study With RNAi Therapeutics Targeting Liver Angiotensinogen
Authors: Mirabito Colafella Katrina M , Uijl Estrellita , van Veghel Richard , de Vries René , Garrelds Ingrid M , Hoorn Ewout J , Poglitsch Marko , Kim Jae , Foster Don , Danser A.H. Jan
Published: December 2018

Angiotensinogen (AGT) synthesis is proposed to occur not only in the liver, but also in kidney, brain and adipocytes. Selectively deleting hepatic AGT might therefore not affect renal angiotensin (Ang) levels. Here we investigated whether arterial pressure lowering with liver-targeted AGT siRNA versus renin-Ang system (RAS) blockers affects renal function and Ang levels. Arterial pressure was measured via radiotelemetry in spontaneously hypertensive rats during vehicle, valsartan, captopril (both p.o.), siRNA (s.c. fortnightly injection), siRNA+valsartan or captopril+valsartan treatment for 4 weeks. Transcutaneous measurement of glomerular filtration rate (GFR) and 24h urinary excretory function was assessed at 2 and 4 weeks. Renal Ang levels were measured by mass spectrometry. Dual RAS blockade synergistically lowered arterial pressure compared to monotherapy. Valsartan and captopril increased AngI (1096±205 and 939±128 fmol/g, respectively versus 413±46 fmol/g in vehicle-treated; both P<0.01 vs. vehicle), while captopril+valsartan did not affect AngI (260±42 fmol/g). siRNA and siRNA+valsartan lowered AngI (59±6 and 12±3 fmol/g, respectively; P<0.0001 versus vehicle). Conversely, neither siRNA nor valsartan lowered AngII (228±15 and 338±39 fmol/g versus 431±48 fmol/g in vehicle-treated). Captopril modestly lowered AngII while dual RAS blockade with siRNA+valsartan or captopril+valsartan greatly reduced AngII (115±20, 15±5 and 9±3 fmol/g, respectively; all P<0.0001). The renal AngII/I ratio was increased 4-fold after siRNA (P<0.001), reduced by >70% after valsartan, captopril and captopril+valsartan (all P<0.001) and unaltered after siRNA+valsartan. No treatment affected GFR, natriuresis or albuminuria. In conclusion, the lowering of renal AngI after liver-targeted AGT siRNA suggests that hepatic rather than renal AGT determines renal Ang generation. Upregulation of ACE and/or AT
1
R may allow renal AngII to remain intact after AGT siRNA, and only dual RAS blockade significantly reduces renal AngII. AGT siRNA synergistically lowers arterial pressure when combined with existing RAS blockers and may be a novel treatment for hypertension without apparent negative effects on renal function.
Abstract P111: ELABELA Antagonizes Intrarenal Renin to Lower Blood Pressure and Protect Against Renal Injury
Authors: Xu Chuanming , Wang Fei , Chen Yanting , Xie Shiying , Luo Renfei , Sng Danielle , Reversade Bruno , Yang Tianxin
Published: December 2018

Emerging evidence has demonstrated that (pro)renin receptor (PRR)-mediated activation of intrarenal renin-angiotensin system (RAS) plays an essential role in renal handling of Na
+
and water balance and blood pressure. The present study tested the possibility that the intrarenal RAS served as a molecular target for the protective action of ELABELA (ELA, also known as Toddler/Apela), a novel endogenous ligand of APJ receptor (also known as APLNR) in the distal nephron. By RNAscope and immunofluorescence, mRNA and protein expression of endogenous ELA was consistently localized to the collecting duct (CD). In cultured CD-derived M1 cells, exogenous ELA induced parallel decreases of fPRR (by 31.6%), soluble PRR (sPRR) (by 46.5%), and prorenin (by 45.7%) protein expression as assessed by immunoblotting, and medium sPRR (by 66.7%) and prorenin/renin (by 60%) levels by ELISA. Conversely, deletion of PRR in the CD in mice elevated ELA mRNA levels (1.5-fold), and urinary ELA excretion (2.0-fold), supporting the antagonistic relationship between the two systems. Administration of exogenous ELA (5 mg/kg/day, minipump) to high salt (HS)-loaded Dahl salt-sensitive (SS) rats significantly lowered mean arterial pressure (113.0 ± 1.7
vs
. 133.8 ± 1.5 mmHg,
P
<0.001), systolic blood pressure (BP) (122.5 ± 1.8
vs
. 142.9 ± 2.6 mmHg,
P
<0.01), diastolic BP (105.8 ± 2.3
vs
. 127.4 ± 0.9 mmHg,
P
<0.001), heart rate (347.4 ± 4.9
vs
. 394.1 ± 5.3 bpm,
P
<0.001), and albuminuria (11.4 ± 1.0
vs
. 5.1 ± 1.1 mg/24h,
P
<0.01), accompanied with a reduction of urinary sPRR (by 53.3%), Ang II (by 54.6%), prorenin/renin (by 68.7%), neutrophil gelatinase-associated lipocalin (by 51.9%), and prostaglandin E2 (by 44.9%) excretion. HS upregulated renal medullary protein expression of fPRR (218.7%) and sPRR (172.4%) in Dahl SS rats, all of which were significantly blunted by exogenous ELA infusion (by 30-55%). Together, these results support the antagonist interaction between ELA and intrarenal RAS in the distal nephron that appears to exert a major impact on blood pressure regulation.
Abstract P114: Predominance of Formation Over Degradation as Mechanism of Angiotensin-II(1-8) Regulation in Aminopeptidase a deficient Kidneys
Authors: Marahrens Benedikt , Wysocki Jan , Velez Juan-Carlos , Bader Micheal , Batlle Daniel
Published: December 2018

Aminopeptidase A (APA), Angiotensin Converting Enzyme (ACE)-2, Neprilysin (NEP) and other enzymes degrade Angiotensin(Ang)-II, whereas ACE is the main AngII(1-8) forming enzyme. Our objective was to determine the state of the enzymes that form and degrade AngII(1-8) within the kidney when APA, a main degrading enzyme, is absent. We used a mouse model of APA deficiency on Balb/c genetic background. AngII(1-8) levels measured by ELISA in kidneys from APA deficient mice were higher than in control (0.3±0.01 vs 1.1±0.15 fmol/mg protein, p=0.001). In APAKO kidneys, ACE activity was markedly reduced to approximately 50% of the activity levels in WT mice (28229±4105 vs 14275±1895 RFU/ug total protein, p=0.006). In concordance with the activity assay the relative abundance of ACE protein in APAKO was reduced by Western Blot (1.2±0.14 vs 0.1±0.06, p<0.001). mRNA levels were also markedly reduced (0.94±0.12 vs 0.45±0.05, p=0.006). Surprisingly, enzyme activities of ACE2 (30±3.7 vs 16±3.1 RFU/ug total protein/hr, p=0.009) and NEP (2.4±0.4 vs 1.1±0.3 RFU/ug total protein/hr, p=0.013) were lower in APAKO (n=10) as compared to WT kidneys (n=11). In conclusion, in kidneys from APAKO mice there is an unexpected decrease in AngII(1-8) degrading enzymes. Rather a marked transcriptional downregulation of ACE occurs as the main compensatory mechanism to reduce AngII(1-8) formation. We conclude that elevated AngII(1-8) levels in the kidney lead to a downregulation of ACE transcription as a negative feedback to attenuate AngII(1-8) accumulation.
Abstract P129: Renal Necrotic Tissue Induces Hypertension
Authors: Wei Jin , Zhang Jie , Wang Lei , Liu Ruisheng
Published: December 2018

The effect of renal necrotic tissue on blood pressure remain unclear. We hypothesized that infarcted renal tissue induces hypertension by stimulating inflammatory response. Partial renal infarction models were developed by ligating either upper branch (UL group) or lower branch (LL group) in the left renal artery. Mean arterial pressure (MAP) measured with telemetry quickly increased from 3 days after surgery, then gradually declined and reached a plateau within 7 days after surgery, which was 120.4±4.6 mmHg (increased by 23.8±2.5%) in UL group and 114.3±5.6 mmHg (increased by 19.0±1.1%) in LL group (n=8, p<0.01 vs baseline). Moreover, resection of the renal necrotic zone at day 14
th
after ligation surgery normalized the MAP in partial renal infarction groups at day 28
th
(UL+R: 121.1±5.9 to 98.3±5.1 mmHg; LL+R: 118.6±4.7 to 101.5±3.6 mmHg). The protein levels of TNFα and IL-6 in the left kidney homogenate significantly increased in UL group (11.5±3.4-fold; 3.8±1.2-fold) and LL group (8.4±2.7-fold; 2.7±0.83-fold) compared with the sham group at day 28 after ligation surgery (n=5, p<0.01 vs sham). Plasma concentration of TNFα and IL-6 also elevated in UL group (3.5±1.2-fold; 2.4±0.4-fold) and LL group (3.8±0.9-fold; 2.9±0.7-fold) at day 28 (n=7, p<0.01 vs sham). Inflammatory cell infiltration was significantly enhanced in UL (337±45 Inflammatory cells/HPF) and LL groups (314±27 Inflammatory cells/HPF) compared with sham group (22±14 Inflammatory cells/HPF) (n=7, p<0.01 vs sham). Moreover, resection of the renal necrotic zone at day 14
th
after ligation surgery normalized the inflammatory response at day 28
th
in UL+R and LL+R groups, compared with UL and LL groups. We concluded that renal necrotic tissue induces hypertension in C57BL/6 mice, possibly by stimulating of the inflammatory response.
Abstract P130: Acute Hyperlipidemia Increases Vasodilation in Conduit Arteries but Has No Effect on Microvascular Recruitment in African American Women
Authors: Celedonio Jorge E , Mehr Shahram , Gottlieb JoAnn , Biaggioni Italo , Shibao Cyndya
Published: December 2018

African Americans have one of the highest prevalence of hypertension in the United States. Impaired endothelial function has been implicated in the pathophysiology of hypertension in this group. We previously reported that brachial artery diameter increases from 3.9±0.14 to 4.1± 0.14 at 4 hours after ingestion of a high fat meal, suggesting vasodilation of conduit arteries. Considering that oral fat ingestion stimulates the release of gastrointestinal peptides with vasoactive properties, we aimed to isolate the vascular effect of fat on conduit artery and microvasculature by inducing an acute elevation of triglycerides and free fatty acids with an infusion of 20% intralipid® and heparin. To assess endothelial function we measured changes in the diameter of the brachial artery to hyperemia with a continuous edge detection and wall tracking software. Effect on microvasculature was obtained with contrast-enhanced ultrasonography (CEU) of the brachioradialis muscle with lipid-perflutren microbubbles infusion. We studied 14 obese healthy African American women, age 39± 10, BMI 38.7± 3.4 kg/m.
2
Triglycerides increased from 60.7±30.5 to 523.3±231 mg/dL at the end of the 4 h infusion. Brachial artery diameters were 3.6±0.16 and 3.9±0.18 mm at baseline, and 4-h, P=0.109, respectively. Flow mediated dilation improved at the end of the 4-h infusion period (4.3±0.95 to 6.2±1.21%, P=0.016),
figure
. Microvascular blood volume did not change with the intervention 5.8±4.9 vs. 5.9±3.6, P=0.55. In conclusion, IV acute hyperlipidemia did not increase brachial artery diameter nor microvascular circulation, however it potentiates vascular reactivity in conduit arteries.
Abstract P132: Everolimus, a Targeted Cancer Therapy, Improves Endothelium Dependent Relaxation in Spontaneously Hypertensive Rat Mesenteric Arteries
Authors: Martinez Quinones Patricia , McCarthy Cameron G , Wenceslau Camilla F , Webb R Clinton
Published: December 2018

Cardiovascular disease is the leading cause of death in cancer survivors. The short-term and long-term cardiotoxic effects of targeted chemotherapeutics is not well known. Everolimus, an inhibitor to mammalian target of rapamycin (mTOR) complex 1, is a targeted therapy approved for the treatment of metastatic breast, colon, renal cell and pancreatic cancer. Clinical retrospective reviews suggest heart failure and hypertension as cardiotoxic effects of everolimus. Our lab previously showed that everolimus exposure on normotensive vessels increased sensitivity to adrenergic stimuli in a time and concentration dependent manner. We hypothesized that everolimus leads to enhanced contractility and impaired relaxation in hypertensive vessels. We studied the effects of everolimus on the contractility and relaxation of mesenteric resistance arteries (MRA) of male Wistar rats (12-15 weeks old, n=4) and spontaneously hypertensive rats (SHR) (15-18 weeks old, n=2) on a wire myograph. Two concentrations of everolimus were evaluated, 0.1μM and 0.1nM, during a one-hour incubation. Normotensive MRA exposed to everolimus (0.1μM) showed a decreased contractile response to phenylephrine (LogEC50
+
SEM, Ctrl:-5.627
+
0.07 vs Drug: -5.390
+
0.10) but no difference when exposed to 0.1nM. SHR MRA showed no difference in PE-induced contraction at 0.1μM (LogEC50
+
SEM, Ctrl:-5.638
+
0.08 vs Drug:-6.286
+
0.36) or 0.1nM (LogEC50
+
SEM, Ctrl:-5.638
+
0.08 vs Drug:-5.332
+
0.16). No differences were observed in endothelium dependent relaxation response to acetylcholine (ACh) for either drug concentration in the normotensive vessels; however, SHR MRA exhibited enhanced sensitivity to ACh with everolimus exposure (LogEC50
+
SEM, Ctrl: -6.851
+
0.15 vs Drug:-9.233
+
0.37 at 0.1nM; LogEC50
+
SEM, Ctrl: -6.851
+
0.15 vs Drug:-8.244
+
0.34 at 0.1μM). Our data show that everolimus affects contractility in normotensive vessels, while affecting the dilatory response in SHR vessels with an improvement in endothelium-dependent relaxation. Everolimus may be a good therapeutic agent for hypertensive cancer patients. However, long term treatments with this targeted therapy need to be evaluated for vascular dysfunction induction, which could be associated with cardiotoxicity.
Abstract P141: Aging in Mice Enhances Microvascular Reactive Oxygen Species (ROS) That Impair the Anti-Contractile Actions of Perivascular Adipose Tissue (PVAT)
Authors: Li Tian , WILCOX Christopher S , Wang Dan
Published: December 2018

Background:
Reactive oxygen species (ROS) contribute to oxidative stress and aging that predicts cardiovascular disease (CVD). Perivascular adipose tissue (PVAT) enhances endothelial function and reduces contractility of normal vessels. We tested the hypothesis that ROS and age impair PVAT signaling using mesenteric arterioles (MAs) from young and old wild type (Wt) and superoxide dismutase 3 knockout mice (KO).

Methods and Results:
MAs were isolated with and without PVAT from young (3 – 4 months; n = 5 – 7) and old (23 – 24 months; n = 5 – 7) wild-type (Wt) and superoxide dismutase 3 knockout (-/-) mice (to create oxidative stress). Contractions were assessed on an isometric myograph and ROS and mitochondrial ROS by fluorescence microscopy in MAs loaded with dihydroethidium or MitoSOX Red. The increase in ROS and mitochondrial ROS signals with 10
-7
mol·l
-1
endothelin 1 (ET1) were increased in MAs from Wt old vs young mice (0.21 ± 0.05 vs 0.11 ± 0.04 units; P<0.05 and 0.15 ± 0.04 vs 0.08 ± 0.04 units; P<0.05 respectively). Amongst Wt mice, the effect of PVAT to reduce contractions to 10
-6
mol·l
-1
U-46,619 was reduced in old vs young mice (15 ± 1 vs 45 ± 6% reduction; P<0.005) with similarly reduced effects of PVAT in vessels from old mice on contractions to 10
-7
mol·l
-1
endothelin 1 (ET1: 15 ± 4 vs 34 ± 3% reduction; P<0.005). Compared to young Wt mice, MAs from young SOD3 -/- mice had reduced protection by PVAT from contractions to U-46,619 (25 ± 3 vs 45 ± 6% reduction; P<0.01) or to ET1 (3 ± 2 vs 34 ± 8% reduction; P<0.005). The effects of oxidative stress to lessen the protective effects of PVAT were lessened in old mice where the reductions in contractions mediated by PVAT to U-46,619 were no longer different in SOD +/+ vs -/- mouse MAs (12 ± 1 vs 15 ± 1% reduction; NS) while contractions to ET1 remained somewhat protected by PVAT (8 ± 2 vs 15 ± 4% reduced; P<0.05).

Conclusions:
Aging enhances ROS generation by mesenteric arterioles that impairs the beneficial effects of PVAT to protect vessels from contractions with thromboxane and endothelin. This discloses a novel mechanism for age-related cardiovascular disease.
Abstract P146: Cytochrome B5 Reductase (CYB5R3) Function in Smooth Muscle Cells and Blood Pressure Regulation
Authors: Durgin Brittany G , Hahn Scott A , Miller Megan P , Straub Adam C
Published: December 2018

Hypertension (HTN) is a major risk factor for cardiovascular-related morbidity and mortality. Dysregulation of nitric oxide (NO) signaling has been found in both human and mouse studies to impact the renin-angiotensin-aldosterone system (RAAS) and contribute to the vascular dysfunction leading to HTN. NO signals via soluble guanylyl cyclase (sGC) to generate cyclic guanosine monophosphate (cGMP) and downstream activation of protein kinase G (PKG) to induce vasodilation. However, the sGC heme iron needs to be in the reduced (Fe
2+
) state for NO to bind as oxidized (Fe
3+
) sGC is insensitive to NO signaling. We found that NADH cytochrome b5 reductase 3 (CYB5R3) is a sGC heme reductase that maintains sGC heme iron in its reduced state. Transient knockdown and pharmacological inhibition of CYB5R3 in smooth muscle cells (SMCs) blocks NO-mediated cGMP production and aortic relaxation. Taken together, we hypothesized that SMC CYB5R3 was important in blood pressure regulation. We created tamoxifen-inducible SMC-specific CYB5R3 knockout mice (SMC CYB5R3 KO) and found that they (n=8) had an ~5 mmHg increase in mean arterial blood pressure at baseline as compared to SMC CYB5R3 WT mice (n=9). In response to Angiotensin II (Ang II)-induced hypertension, SMC CYB5R3 KO mice (n=5) exhibited an ~14 mmHg increase in blood pressure and a significantly reduced heart rate as compared to SMC CYB5R3 WT mice (n=5). Lastly, ex vivo two-pin wire myography of Ang II-induced hypertensive SMC CYB5R3 KO (n= 6) mesenteric arteries treated with NO-independent sGC activator Bay 58-2667 showed increased vasodilation as compared to SMC CYB5R3 WT mice (n=10); Bay 58-2667 treatment at baseline showed no difference between groups. We predict that CYB5R3 regulation of SMC sGC heme iron redox state influences blood pressure in a NO-dependent manner. To test this, we will perform an intervention study where we will measure blood pressure in Ang II-induced hypertensive SMC CYB5R3 WT and SMC CYB5R3 KO mice treated with Bay 41-2272, a NO and heme dependent sGC stimulator, and Bay 58-2667. Also, we will assess the role of SMC CYB5R3 in protection against Ang II-induced vessel fibrosis and SMC dysfunction.
Abstract P151: Short- and Long-Term Induction of Human Endothelin-1 Overexpression in Mice Up-Regulated the Expression of
Khdrbs3
in Mesenteric Arteries
Authors: Berillo Olga , Coelho Suellen C , Huo Ku-Geng , Ouerd Sofiane , Richer Chantal , Sinnett Daniel , Paradis Pierre , Schiffrin Ernesto L
Published: December 2018

Background:
Transgenic mouse with tamoxifen-inducible endothelium-restricted human ET-1 overexpression (ieET-1) exhibited blood pressure (BP) elevation three weeks (short-term) and three months after induction (long-term). Vascular injury was observed only after long-term exposure to endothelial ET-1 overexpression. It is unknown whether short or long-term exposure to ET-1 overexpression results in gene dysregulation. We aimed to identify differentially expressed (DE) microRNAs (miRs) and genes in mesenteric arteries of ieET-1 mice after short- and long-term induction of human ET-1 overexpression.

Methods and Results:
Ten to 12-week old male ieET-1 mice and control ieCre mice expressing a tamoxifen-inducible Cre recombinase under the control of endothelium-specific
Tie2
promoter, were treated with tamoxifen (1 mg/kg/day, s.c.) for 5 days and sacrificed 16 days or 3 month later. RNA was extracted from mesenteric arteries of ieCre and ieET-1 mice and used for small and total RNA-sequencing using Illumina HiSeq-2500. EdgeR was used for differential expression analysis (false discovery rate <0.05, fold change ≤ or ≥ 1.5). No DE miRs were identified. DE genes were identified in ieET-1 compared to ieCre mice after short-term induction (mRNAs: 1 up and 6 down; non-coding [nc]RNAs: 3 up) and after long-term induction (mRNA: 1 up).
Khdrbs3
(KH domain containing, RNA binding, signal transduction associated 3), which was up-regulated after both short- and long-term exposure to endothelial ET-1 overexpression, was validated by reverse transcription-quantitative PCR (RT-qPCR). We demonstrated a correlation between RNA-sequencing and RT-qPCR data for short- and long-term groups (r=0.8,
P
<0.0005). The mRNA expression of
Khdrbs3
was 2 times more in fibroblasts than in smooth muscle cells and endothelial cells (2.37±0.28 vs. 1.11±0.17 and 1.12±0.12,
P
<0.01).

Conclusions:
The results showed that short- and long-term exposure to endothelial ET-1 overexpression up-regulated
Khdrbs3
in mesenteric arteries.
In vitro
study revealed that this gene was expressed to a greater level in fibroblasts than other vascular cells. However, the role of
Khdrbs3
in ET-1-induced vascular injury remains to be determined.
Abstract P155: B Cells Are Not Necessary for the Developmentof Ang II-induced Hypertension and End-Organ Damage
Authors: Chen Yuhan , Dale Bethany L , Pandey Arvind K , Alexander Matthew R , Laroumanie Fanny , Madhur Meena S
Published: December 2018

Chronic inflammation characterized by vascular T cell and macrophage infiltration is associated with angiotensin II (Ang II)-induced hypertension and end-organ damage. However, the role of B cells in the development of hypertension is not well established. Elevated levels of serum immunoglobulins have been observed in experimental and human hypertension. Prior studies demonstrated that B-cell-activating factor receptor-deficient (BAFF-R
-/-
) mice, which lack mature B cells, are protected from Ang II-induced hypertension and vascular remodeling. However, BAFF-R can be expressed on non-B cells as well. Thus, to further investigate the role of B cells in hypertension, we studied mice with targeted disruption of the membrane exon of the immunoglobulin μ heavy chain gene (μMT
-/-
) that encodes the constant region of the IgM isotype. In these mice, B cells are arrested at the pre-B cell maturation stage. Serum immunoglobulins were undetectable at a 1:30,000 dilution in μMT
-/-
mice. Interestingly, μMT
-/-
mice exhibited similar blood pressure increase in response to 4 weeks of Ang II infusion compared to age-matched wild type (WT) mice (p=0.675). Flow cytometry of aortae from Ang II-treated μMT
-/-
mice demonstrated fewer CD45+ cells (p=0.047), similar levels of CD8+ and CD4+ T cells (p=0.631 and p=0.721 respectively), a trend for more F4/80+ monocytes/macrophages (p=0.2567), and virtually no CD19+ B cells (p=0.002) compared to WT mice. Endothelium-dependent vasodilatation to acetylcholine was comparable between μMT
-/-
mice and WT mice after Ang II treatment (p=0.223), however μMT
-/-
mice displayed enhanced endothelium-independent vasodilatation to sodium nitroprusside than WT mice (p=0.024). Urinary albumin/creatinine ratio was similar between Ang II-treated μMT
-/-
mice and WT mice (p=0.488), indicating similar renal damage. Taken together, μMT
-/-
mice are not protected from Ang II-induced hypertension, suggesting that B cells and immunoglobulin production are not critical for hypertension and the associated end-organ damage.
Abstract P160: Hypertension is Associated With Monocytes Activation in the Blood in Mice and Humans
Authors: Carmo Luciana S , Xiao Liang , Loperena Roxana , Elijovich Fernando , Rugerri Barbaro Natalia , Harrison David
Published: December 2018

Monocytes play a crucial role in immune activation and the development of hypertension. Deletion of monocytes prevents experimental hypertension, and monocyte derived dendritic cells (DCs) and macrophages promote T cell activation and tissue damage. Our group recently found that monocytes exposed to hypertensive mechanical stretch convert to a pro-inflammatory phenotype denoted by expression CD14
+
CD16
+
, also known as intermediate monocytes. We aimed to determine whether hypertension has a direct effect on the bone marrow to activate the production and mobilization of monocytes. To study this, we initially analyzed the circulating monocytes from 15 normotensive and 12 hypertensive subjects using flow cytometry and found that hypertensive subjects have an absolute monocytosis compared to normotensives (1014 ± 113 vs. 567.5 ± 97 per uL, p < 0.05). This is associated with high numbers in both the classical CD14
+
CD16
-
monocytes and the non-classical CD14
low
CD16
+
monocytes. To further study mechanisms involved, we analyzed monocytes in the blood and bone marrow from C57BL/6 mice following two weeks of sham or Ang II infusion (490 ng/kg/min, s.c.). Similar to the findings in humans, more total monocytes were found in mice with Ang II-induced hypertension (46.7±10.1 vs 18.7±4.7 per μL, p<0.05). Ang II also induced an increase in Ly6C high expressing monocytes (Ang II: 34.1±65.6 vs. Sham: 12.3±3.5 per μL, p<0.05), reflecting activation. We also observed an increase in Ly6C high expressing monocytes in the bone marrow. Taken together, our results suggest that hypertension is associated with monocytosis in humans and mice, and this is likely due to increased BM production. This increase in monocytes may prime the immune system for activation and increased tissue inflammation. Moreover, the level of circulating monocytes might prove to be a useful biomarker of inflammation in hypertension.
Abstract P162: Adiposity-Induced Hypertension is Associated With Sex-Specific Macrophage Infiltration of Mesenteric Perivascular Adipose Tissue in Dahl S Rats.
Authors: Kumar Ramya K , Rockwell Cheryl E , Turley Alexandra E , Garver Hannah , Fink Gregory D , Watts Stephanie W
Published: December 2018

Perivascular adipose tissue (PVAT) may be a key player in mediating adiposity-associated hypertension because of its proximity to blood vessels. Although increased immune cell occupancy in adipose tissue is proposed to couple adiposity to hypertension, little is known about PVAT’s immune complement. We hypothesized that an immune complement exists in PVAT that would become pro-inflammatory with adiposity-induced hypertension. Male and female Dahl S rats were fed a regular (10% calories from fat) diet (control) or a high fat (60%) diet (HFD) from weaning through 24 weeks of age. HFD rats demonstrated significantly higher systolic blood pressure [mm Hg; control: 127±7 (M), 145±8 (F); HFD: 168±9 (M), 184±11 (F); tail cuff] and visceral adiposity (micro-CT scans). PVATs from the thoracic aorta (APVAT), mesenteric resistance vessels (MRPVAT), non-PVAT retroperitoneal fat (RP fat) and spleen (positive control) were harvested from each animal. T cells (CD4 and CD8), B cells, macrophages, mast cells and neutrophils in the stromal vascular fraction were quantified using 7-color flow cytometry. The type and number of immune cells are presented as a percentage (%) of total live singlet cells. Each immune cell type is reported as % of total immune cells, and CD4, CD8 cells as % of T cells. The table illustrates significant (P<0.05) differences with HFD
vs
respective controls. HFD-induced hypertension in Dahl S rats leads to greater macrophage infiltration of MRPVAT and RP fat in females
vs
males. Further studies are needed to gain mechanistic insights into how macrophage subtypes and their associated cytokines in PVAT may alter vascular tone and blood pressure.
Abstract P165: Genetic Polymorphisms Linked to Diabetes With Chronic Renal Insufficiency
Authors: Wang Ling , Wang Donna
Published: December 2018

Chronic kidney disease (CKD) has raised to a global health concern with huge economic burden and detrimental consequences for health. Among the risk factors, diabetes is a leading cause for CKD and renal failure. Multiple studies such as familial aggregation studies have provided evidence for a genetic component to the kidney disease. Heritability estimates of eGFRcrea are reported between 0.41 and 0.75 in individuals with the major CKD risk factors, hypertension and diabetes. However, precise genetic loci predicting CKD with or without diabetes are unknown. Here, we test the hypothesis that genetic polymorphisms are distinct between CKD patients with and without diabetes. We performed a genome-wide association studies using data from the Chronic Renal Insufficiency Cohort (CRIC) study to identify genetic various related to diabetes among CKD patients. CRIC Study is a United States multicenter, prospective study of racially and ethnically diverse patients with CKD. Clean genotype data from 970,342 genotyped or imputed single-nucleotide polymorphisms (SNPs) were available for 3,541 patients (1,953 males and 1,588 females) in CRIC study. Logistic regressions were carried out comparing distribution of SNPs among CKD patients with or without diabetes controlling for confounding factors of gender and race. Among all 3,541 CKD patients in CRIC, 1,724 CKD patients had Diabetes at baseline (Mean of Glycosylated hemoglobin =7.7%). We found that three genes, including
KCNMB4
(rs767397, encoding calcium-activated potassium channel, subfamily M subunit beta 4),
FOXA1
(rs911822, encoding a forkhead transcription factor) and
SIMC1
(rs16831314, encoding SUMO-interacting motif containing protein 1), were putative risk genes for diabetes among CKD patients (P-value<5х10
-6
). These results are the first demonstrating that distinct genetic polymorphisms present in CKD patients with diabetes, indicating that these genes may be used to assess the risk of CKD with diabetes and that proteins encoded by these genes may contribute to diabetic nephropathy.
Abstract P166: Identification of
Cyr61
and
Tfgbi
as Hypertensive Renal LEC Genes
Authors: Balasubbramanian Dakshnapriya , Lopez-Geslton Catalina A , Ighofose Pauline , Saathoff Micaela , Rutkowski Joesph M , Mitchell Brett M
Published: December 2018

Increased renal lymphatic density is observed in various experimental models of hypertension. To identify differentially expressed genes in lymphatic endothelial cells (LECs) from hypertensive kidneys, we utilized Gene Expression Omnibus (GEO) which was developed by the NIH NCBI. GEO is an international public repository that archives and distributes high-throughput functional genomic data sets such as microarray and next-generation sequencing data. GEO2R is an interactive web tool that allows users to compare samples across experimental conditions in a GEO Series in order to identify genes that are differentially expressed. Results are presented as a table of genes ordered by significance. Using GEO2R, the search terms “lymphatic” and “hypertensive kidney” were used to identify studies of LEC-associated genes and renal hypertension-associated genes. Among the search results for LEC genes, 4 studies were chosen that were done in mice comparing: a) murine primary LECs vs. murine endothelial SVEC4-10 cell line, b) collecting lymphatic endothelium of mice with 293EBNA xenografts with and without overexpression of VEGFD, c) LECs from afferent and efferent lymphatic vessels, and d) LECs and blood vascular endothelial cells from mouse intestine. For renal hypertensive genes, we chose a study that reported differentially expressed genes in kidneys of mice treated with angiotensin II for 1, 3 or 7 days compared to controls. From all of these lists, the top 250 differentially expressed genes were chosen. The list of renal genes was crossed with a combined list of LEC genes to obtain potential “LEC genes differentially expressed in hypertensive kidneys”. This yielded a list of 40 genes for which mRNA expression was tested in the kidneys of mice from 3 different models of hypertension: nitric oxide inhibition-induced, salt-sensitive, and angiotensin II-induced. Among the differentially expressed genes,
Cyr61
and
Tgfbi
were elevated significantly in all 3 hypertensive models. Cyr61 is a well-known inducer of angiogenesis. Tfgbi is involved in LEC adhesion to extracellular matrix under hypoxic conditions. The upregulation of these two genes likely play a major role in renal LEC function during hypertension.