bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P261: Vasopressin System Components are Dysregulated in Human Preeclamptic Placenta
Authors: Deng Guorui , Perschbacher Katherine J , Sandgren Jeremy A , Yu Nanmeng , Scroggins Sabrina M , Devor Eric J , Santillan Donna A , Gibson-Corley Katherine N , Sigmund Curt D , Kwitek Anne E , Santillan Mark K , Grobe Justin L
Published: March 2022

Preeclampsia (PE) is a cardiovascular disorder of late pregnancy characterized by pregnancy-specific onset of hypertension and proteinuria. Although initiating events leading to PE development remain unclear, emerging studies suggest arginine vasopressin (AVP) signaling may contribute to PE pathogenesis, as elevated circulating copeptin (a stable biomarker of AVP secretion) levels precede the onset of human PE, and chronic infusion of AVP into wildtype mice phenocopies PE. Here, we tested the hypothesis that AVP signaling is dysregulated in PE placenta by performing
in-silico
reanalysis of a publically available gene expression dataset derived from placentas of human PE and normal pregnancies (GSE75010). Significant increases in expression [log
2
values] of
AVP
(Con: 6.96 ± 0.02, PE: 7.03 ± 0.17, p=0.005) and its receptors
AVPR1a
(Con: 5.73 ± 0.02, PE: 5.80 ± 0.02, p=0.03) and
OXTR
(Con: 6.58 ± 0.02, PE: 6.65 ± 0.02, p=0.003) were observed in PE placentas (n=80) compared to normal placentas (n=77). Preeclamptic placentas also displayed an enrichment in a hypoxic gene signature, as shown by gene set enrichment analyses (NES: 1.75, FDR q<0.001, FWER p <0.001), suggesting that these placentas exhibited increased hypoxia-related signaling. Interestingly,
AVPR1a
expression as well as
OXTR
is positively and significantly correlated with the expression of two hypoxia-inducible genes
HK2
and
DDIT4
(
AVPR1a
v
HK2
: r
2
=0.04, p=0.02,
AVPR1a
v
DDIT4
: r
2
=0.06, p=0.003,
OXTR
v
HK2
: r
2
=0.05, p=0.007,
OXTR
v
DDIT4
: r
2
=0.04, p=0.008). To further elucidate the role hypoxia may play in promoting AVP signaling, HTR8/SVNeo cells (immortalized human first trimester trophoblasts) were treated with the hypoxia mimetic dimethyloxallyl glycine (DMOG). DMOG incubation did not significantly alter the expression of
AVP
and
AVPR1a
. Unexpectedly, a marked reduction in
OXTR
expression was observed upon DMOG treatment. In summary, these data suggest that 1) components of the AVP signaling pathway are aberrantly expressed in human PE placentas, 2) PE placentas exhibit a gene expression signature consistent with increased canonical hypoxia signaling, and 3) hypoxia may not be the cause of elevated placental
AVP
,
AVPR1a
, and
OXTR
expression in human PE.
Abstract P266: Immunological Characterization of the Dahl SS Model of Superimposed Preeclampsia
Authors: Taylor Erin B , George Eric M , Garrett Michael R , Ryan Michael J , Sasser Jennifer M
Published: March 2022

Patients with existing hypertension and renal disease have an increased risk for developing superimposed preeclampsia. The Dahl SS rat has been shown to be a model of superimposed spontaneous preeclampsia characterized by exacerbated hypertension, increased urinary protein excretion, and increased fetal demise. Because of the underlying immune system dysfunction present in preeclamptic pregnancies in humans, we hypothesized that the Dahl SS rat would also have an altered immune status. In the present study, Dahl SS rats fed a normal (0.3%) salt diet were compared to normal pregnant Sprague Dawley (NP) rats. On gestational day 19, spleens and placentas were collected for flow cytometric analyses. Splenic CD3
+
CD4
+
T cells were analyzed for cytokine production after polyclonal stimulation with phorbol myristate acetate and calcium ionophore to elicit a primary cytokine response. Dahl SS rats had increased percentages of inflammatory TNF
a
+
T cells as compared to NP rats (4.8±0.3% vs. 1.9±0.4%, p<0.001), but there were no significant differences in percentages of IFN-γ
+
, IL-4
+
, or IL-17
+
splenic T cells. Analyses of placental lymphocytes revealed that Dahl SS rats had increased percentages of placental CD3
+
CD4
+
T cells as compared to NP rats (24.3±1.2% vs. 7.6±1.3% , p<0.0001) as well as CD3
+
CD8
+
T cells (9.2±0.5% vs. 4.9±0.4% , p<0.001), but there was no difference in CD45RA
+
B cells. For comparison, we also assessed placental leukocytes in the established reduced uterine perfusion pressure (RUPP) model that mimics characteristics of preeclampsia. Previous studies have reported that pregnant Sprague Dawley rats with surgically induced RUPP have aberrant immune system function which contributes to the pathophysiology of the preeclamptic phenotype in this model. While placentas from RUPP rats had an increase in placental CD3
+
CD4
+
T cells as compared to NP rats (14.9±1.9% vs. 7.6±1.3% p<0.001), similar to pregnant Dahl SS, the percentages of CD3
+
CD8
+
T cells and CD45RA
+
B cells were not significantly different. Taken together, these data demonstrate an association between proinflammatory T cells and superimposed preeclampsia, and suggest that different immunological mechanisms may contribute to the pathogenesis of preeclampsia in different models.
Abstract P268: Overexpression of miR-210 Induces Preeclampsia-like Symptoms in Pregnant Mice by Attenuating the STAT6/IL-4 Pathway
Authors: Bounds Kelsey R , Chiasson Valorie L , Engelbrecht Rachel M , Pan Lu J , Chatterjee Piyali
Published: March 2022

Preeclampsia (PE) is a pregnancy-related hypertensive disorder that affects 5-8% of all pregnancies worldwide. Placental microRNA (miRNA) expression is known to be dysregulated during PE which includes miR-210. However, the role of miR-210 in the development of PE is still unknown. We have previously demonstrated STAT6, a transcription factor, to be a direct target of miR-210. In addition, STAT6 modulates levels of IL-4, an anti-inflammatory cytokine which is known to be beneficial during pregnancy. Given that the STAT6/IL-4 pathway is important for normal pregnancy, we hypothesized that an overexpression of miR-210 in mice will contribute to PE-like symptoms by inhibiting the STAT6/IL-4 pathway. Systolic blood pressures (SBP) were measured using the tail-cuff method on both WT (C57Bl/6J) and miR-210 TG mice. The miR-210 TG mice exhibited increased SBP compared to the WT mice (WT: 95±2 mmHg, miR-210 TG: 115±2.4 mmHg, p<0.05). The miR-210 TG mice also displayed endothelial dysfunction measured by aortic vascular reactivity using wire myography (WT: 93% miR-210 TG: 68% relaxation, p<0.05 vs. WT) and a significant increase in proteinuria (4 fold, p<0.05 vs. WT). Furthermore, the miR-210 TG mice exhibit placental necrosis and a significant increase in the number of malformed pups. Placental STAT6 levels decreased in miR-210 TG compared to WT mice (2.6 fold, p<0.05 vs. WT) as determined by immunoblotting. In addition, qRT-PCR analysis of the miR-210 TG placentas exhibited a (4.8 fold, p<0.05 vs. WT) decrease in IL-4 expression. Immunoblotting and immunohistochemistry (IHC) studies showed a decrease in IL-4 levels (2.4 fold, p<0.05 vs. WT) and immunoreactivity in the miR-210 TG placentas as well as. IHC studies in human placentas also showed a decrease in both IL-4 and STAT6. Based on our results, miR-210 overexpression induces PE-like symptoms including hypertension, endothelial dysfunction, proteinuria, and malformed pups in pregnant mice. In addition, miR-210 overexpression attenuated the STAT6/IL-4 anti-inflammatory pathway. Our data suggests that either targeting miR-210 or the STAT6/1L-4 pathway could be a potential therapeutic in mitigating the symptoms of PE.
Abstract P274: Double Hit! A Unique Case of Resistant Hypertension
Authors: DeCarlo Kristen , Agrawal Nidhi
Published: March 2022

Case Description:
A 52 year-old woman with obesity, HLD, diet-controlled diabetes was referred for resistant hypertension. Her blood pressure (BP) was uncontrolled (systolic 145-200 mmHg, diastolic 95-135 mmHg) on 5 medications. Physical exam revealed a systolic ejection murmur at the base. An ECHO showed normal systolic function and moderate LVH. Plasma aldosterone was 20.7 ng/dL (normal 3-15 g/dL), plasma renin was 0.50 ng/mL/h (normal 0.65-5.0 ng/mL/h), and aldosterone:renin ratio was 41.4 [ng/dL]/[ng/mL/h], meeting criteria for Primary Aldosteronism (PA). Saline infusion test was confirmatory for PA. CT scan of the adrenals did not reveal an adenoma. Subsequent Adrenal Venous Sampling confirmed bilateral Idiopathic Adrenal Hyperplasia (IAH; right and left adrenal vein selectivity index of 42.6, 9.2 respectively; lateralization index was 1.3). She was normokalemic (3.7-4.4 mEq/L), total calcium (Ca) was 11.2 mg/dL (normal Ca 8.0-10.4), and creatinine was 1.4 mg/dL (GFR 47 mL/min/1.73m
2
). Intact parathyroid hormone (iPTH) was 131.2 pg/mL, phosphorus was 2.4 mg/dL, and 25-hydroxyvitamin D was 30.8 ng/mL, suggesting primary hyperparathyroidism (PPTH). Neck ultrasound was concerning for PTH adenoma and sestamibi scan localized a left adenoma. DXA scan and renal ultrasound were normal. IAH was treated medically with spironolactone. Her BP remained elevated (systolic 138-172 mmHg, diastolic 92-100 mmHg). She underwent parathyroidectomy and histology confirmed an adenoma. Post-operative iPTH and Ca normalized (49.5 pg/mL, 9.7 mg/dL respectively). Postoperative BP measurements improved (systolic 123-138 mmHg, diastolic 75-86 mmHg).

Discussion:
Evidence shows that a hyperfunctioning parathyroid gland may contribute to maintaining hyperaldosteronism in PA. This is based on in-vitro studies showing PTH increased aldosterone secretion from adrenocortical cells in a concentration dependent manner. Gene expression and immunohistochemistry studies show PTH receptors in aldosterone-producing adenomas and MR receptors in parathyroid cells, suggesting a bi-directional relationship. The significance of this case is in the potential for further understanding of the pathophysiology of common causes of secondary hypertension.
Abstract P278: Identification of Differentially Expressed Aortic Genes in Brown Norway Introgressed Chromosome 2 Segments into Hypertensive Dahl Salt Sensitive Rats
Authors: Berillo Olga , Ouerd Sofiane , Huo Ku-Geng , Rehman Asia , Richer Chantal , Sinnett Daniel , Kwitek Anne E , Paradis Pierre , Schiffrin Ernesto L
Published: March 2022

Background:
Rat chromosome (RNO) 2 introgression from normotensive Brown Norway (BN) rats into hypertensive Dahl salt sensitive (SS) background (consomic SB2) reduced vascular inflammation. We hypothesized that the BN-RNO2 contains genes that reduce vascular inflammation, which could be identified using microRNA (miRNA) and total RNA expression profiling in aorta of congenic rats containing different portions of BN-RNO2 on the SS background.

Methods and Results:
Twelve-to-13-week-old male SS rats and congenic rats containing the distal portion of BN-RNO2 (SB2a), the middle segment (SB2b) and the proximal segment (SB2e) on the SS background, fed a normal-salt diet, were studied. Systolic blood pressure (SBP) was measured by telemetry. SBP was lower in SB2a and SB2b but not SB2e compared to SS (125±3, 127±6, 138±4 vs 146±2 mm Hg,
P
<0.05). Total RNA was extracted from aorta and used to construct libraries for small and total RNA sequencing using Illumina HiSeq-2500. The bioinformatics pipeline included: FastQC for quality control, STAR for genome alignment to
Rattus norvegicus
release-86, mirdeep2 for miRNA annotation and counting, Htseq-count for mRNA and long non-coding RNA annotation and counting; R for differential expression analysis. Differentially expressed miRNAs and genes (mRNA and non-coding RNA) were identified in SB2a vs SS (miRNAs: 3 up and 2 down, genes: 1 up and 3 down), SB2b vs SS (miRNAs: 2 up and 3 down, genes: 67 up and 112 down) and SB2e vs SS (miRNAs: 29 up and 25 down, genes: 12 up and 35 down), with FDR<0.05. Differentially expressed genes encoded within different BN-RNO2 congenic portions were identified in SB2a vs SS (2 down), SB2b vs SS (14 up and 18 down) and SB2e vs SS (1 down).

Conclusions and Perspectives:
Differentially expressed BN-RNO2 encoded genes were identified in aorta of congenic SB2a, SB2b and SB2e rats. Whether these genes play a role in inflammation or vascular injury remains to be determined.
Abstract P280: Butyric Acid Protects Against Aldosterone-salt-induced Hypertension and Renal Injury via Suppression of (Pro) Renin Receptor
Authors: Peng Kexin , Zhao Long , Xu Chuanming , Wang Fei , Yang Tianxin
Published: March 2022

Butyric acid (BA), a short-chain fatty acid derived from gut microbiota, exhibits beneficial effects on cardiovascular disease. We examined the potential antihypertensive and renal protective action of BA in a mouse model of aldosterone (Aldo)-salt-induced hypertension. C57/BL6 mice were subjected to Aldo-salt protocol consisting of minipump infusion of Aldo at 0.2 mg/kg/d plus 1% NaCl as drinking fluid, or in combination with minipump infusion of BA at 60 mg/kg/d. A 3-wk BA treatment lowered radio telemetry-measured MAP (146±3.8 vs. 133±2.9 mmHg, N=9, p<0.05), cardiac hypertrophy (6.7±0.32 vs. 5.4±0.28 mg/g body weight, N=9, p<0.05), 24-h urinary albumin (434±41vs. 218±22 μg/24h, N=9, p<0.01), the kidney hypertrophy (9.9±0.58 vs. 7.9±0.38 mg/g body weight, N=9, p<0.05), polyuria (19.5 ± 2.5 vs. 8.7±1.4 ml/24h, N=6, p<0.01), renal 8-isoprostane (0.74±0.14 vs. 0.35±0.05 pg/mg, N=6, p<0.05), and urinary TBARS (276±43 vs. 133±032 nmol/24h, N=9, p<0.05). The hematocrit was decreased by Aldo-salt, which was reversed by BA (Control: 50.0±0.4% vs. Aldo-salt: 46.2±0.8% vs. Aldo-salt + BA: 49.6±1.0%, all N=9, all p<0.05). Recent study has identified (pro) renin receptor as a key regulator of blood pressure. To examine the underlying mechanism of BA on Aldo-salt induced effect, we detected full length (pro) renin receptor (fPRR) and soluble PRR (sPRR) expression in vivo and in vitro in this study. The renal expression of fPRR and sPRR were increased 1.75-fold and 2.67-fold by Aldo-salt treatment, respectively, and these increases were both blocked by BA (1.75±0.08 vs. 0.93±0.14, N=6, p<0.01; 2.67±0.23 vs. 0.92±0.29, N=6, p<0.01, respectively). The Aldo-salt induced urinary sPRR excretion was also blunted by BA (Control: 1533±73 vs. Aldo-salt: 4800±365 vs. Aldo-salt + BA: 2615±138 pg/24h, all N=6, all p<0.05). In cultured mpkCCD cells, Aldo treatment induced protein expression of fPRR and sPRR, which were blocked by BA (fPRR: 1.25±0.09 vs. 0.73±0.08, N=5, p<0.01; sPRR: 2.33±0.35 vs. 1.03±0.15, N=5, p<0.01). Our results suggest that BA protected against Aldo-salt-induced hypertension and renal injury likely through suppression of PRR.
Abstract P281: Urinary Metabolites Associated With Blood Pressure on a Low- or High-sodium Diet
Authors: Xue Hong , Cheng Yuan , Song Haiying , Pan Xiaoqing , Wan Yifei , Wang Tao , Tian Zhongmin , Hou Entai , Lanza Ian R , Liu Pengyuan , Liu Yong , Laud Purushottam W , Usa Kristie , He Yongcheng , Liang Mingyu
Published: March 2022

Dietary salt intake has significant effects on arterial blood pressure and the development of hypertension. Mechanisms underlying salt-dependent changes in blood pressure remain poorly understood. The goal of the present study was to utilize urine samples from the Dietary Approaches to Stop Hypertension (DASH)-Sodium trial and a targeted metabolomic approach to identify associations of urinary metabolites with blood pressure phenotypes on low- or high-sodium intake. We examined urinary levels of metabolites in 103 participants of the DASH-Sodium trial after 30 days on a defined diet containing high sodium (targeting 150 mmol sodium intake per day) or low sodium (50 mmol sodium per day). Systolic or diastolic pressure was 10 or more mmHg higher on the high-sodium intake in 51 of the 103 participants. Targeted chromatography/mass spectrometry analysis was performed in 24-h urine samples for 10 metabolites related to the tricarboxylic acid cycle and 47 amino metabolites. Urinary metabolite levels improved the prediction of classification of blood pressure salt-sensitivity based on race, age and sex. Random forest and generalized linear mixed model analyses identified significant (false discovery rate <0.05) associations between 24 h excretions of β-aminoisobutyric acid, cystine, citrulline, homocysteine and lysine and systolic blood pressure and between cystine and diastolic blood pressure. The differences of 24 h excretion of homocysteine between low- and high-sodium intakes were significantly associated with the differences in diastolic blood pressure. These associations were significant with or without considering demographic factors. Treatment with β-aminoisobutyric acid significantly attenuated high-salt-induced hypertension in Dahl salt-sensitive rats. These findings support the presence of new mechanisms of blood pressure regulation involving metabolic intermediaries.
Abstract P283: Effects of High Salt Diet on Vascular Function and Renal Injury in a Novel Mouse Model of Neurogenic Hypertension
Authors: Nakagawa Pablo , Agbor Larry N , Nair Anand , Gomez Javier , Hu Chunyan , Wu Jing , Sigmund Curt D
Published: March 2022

In the brain, transcription of the renin gene is initiated from an alternative promoter within exon 1b resulting in the expression of Renin-b, a renin isoform lacking the signal peptide and first third of the prosegment. The specific deletion of Renin-b paradoxically induces neurogenic hypertension concomitant with increased brain renin-angiotensin system and renal sympathetic nerve activation. High dietary sodium intake has been associated with hypertension, endothelial dysfunction, and renal complications especially in salt-sensitive populations. We hypothesized that deletion of Renin-b causes vascular dysfunction and induces renal damage. In addition, high dietary sodium intake further exacerbates end-organ damage in Renin-b deficient mice (Ren-b KO). To evaluate vascular function, acetycholine (Ach) and nitroprusside (SNP)-induced dose-dependent vasorelaxation was assessed in aorta, carotid and basilar arteries isolated from Ren-b KO or littermate controls fed normal or high sodium diet (4% NaCl) for 4 weeks. Urinary protein excretion was measured at baseline and after 4 weeks on high sodium diet in control and Ren-b KO mice. At baseline, Ren-b KO exhibited impaired Ach-induced vasorelaxation in the aorta (logEC50 control: 0.88mM vs Ren-b KO: 1.1mM; p = 0.014; n=4) while SNP dose-response curve was unaltered. Urinary protein levels were increased in Ren-b KO (control: 11.0±3.7 vs Ren-b KO: 45.8±9.3 mg/day; p = 0.007; n=6-8). In control mice, 4 weeks high sodium diet increased urinary protein levels compared to baseline (baseline: 11.0±3.7 vs high salt: 31.6±7.4 mg/day); however high salt diet did not worsen proteinuria in Ren-b KO (baseline: 45.8±9.3 vs high salt: 44.1±4.5 mg/day). Similarly, Ren-b KO fed high sodium diet did not exhibit higher degrees of vascular dysfunction in comparison with control mice on high sodium diet. Our data indicates that Renin-b deletion promotes end-organ damage, likely as a consequence of high blood pressure or sympathetic nerve activation or both. Surprisingly, high sodium diet failed to exacerbate vascular dysfunction or proteinuria in Ren-b KO. Studies are in progress to evaluate the blood pressure response to high sodium diet in Ren-b KO mice to assess if Ren-b KO mice are salt sensitive.
Abstract P292: Reversal of Cardiac Remodeling After Surgical Intervention Leads to Distinct Cardiac Function Outcomes
Authors: Jensen Leonardo , Almeida Silva Amanda , Cunha Oliveira Nataly , Eziquiel de Souza Leandro , Costa Irigoyen Maria Claudia
Published: March 2022

Hypertension is the leading cause of cardiovascular diseases Nevertheless diagnosed hypertension can be controlled and monitored with adequate drug regimens. Yet once cardiac hypertrophy is established, a number of patients develop diastolic cardiac dysfunction resulting from cardiac remodeling with fibrosis and cell death. The present study aims to test the hypothesis that animals with aortic stenosis for five weeks can restore cardiac function after the removal of the aortic constriction. Male mice with 10 weeks of age were randomized in three groups
Sham
,
Rem
, and
Tac
. After five weeks of the establishment of cardiac hypertrophy the aortic constriction was removed and the animals were followed for additional five weeks
Rem
. The positive control group
Tac
remained with the clip until ten weeks. Echocardiography was performed after 72 hours of the removal of the five weeks stenosis
Rem
and at the end of ten weeks. We also used cutoff points based on sham group for the ejection fraction
EF≥45%
and the ratio of E wave per e’
E/e’≤35
. The Rem group was separated into two outcomes according to the presence of dysfunction. Results were expressed as mean ± standard error of the mean SEM. Statistical analyses were performed and p≤0.05 were considered statistically significant. Septum thickness increased after five weeks of stenosis in both Rem 0.812±0.01mm and Tac 0.764±0.02mm groups as compared to sham group 0.675±0.01mm p≤0.05. Left ventricle mass was significantly different in Sham vs Tac 73.98±2.40mg vs 111.79±11.81mg p<0.0001 After 10 weeks the REM group did not present any hypertrophy markers. Among 18 animals of Rem group, 9 had reduced EF compared to sham after 5 weeks 36.97±1.87%vs52,74±4.17% p<0.0001 and after 10 weeks 49±1.13%vs40±1.06% p<0.0001 constituting an occurrence of systolic problems of 50%. When we analyzed E/e’ 13 animals presented diastolic dysfunction and an increased ratio compared to sham animals 41.07±1.12vs30.79±1.95 p<0.05 at 5 weeks. Therefore, the occurrence of diastolic dysfunction reached 72%. The proposed model induced hypertrophy. Despite that, only half the Rem animals had a reduction in ejection fraction, whereas most developed diastolic dysfunction. These findings open a new path for the investigation of these distinct outcomes
Abstract P294: Leptin Deficiency Reduces Cardiac Reserve Independently of Increased Body Weight
Authors: Gava Fabio N , Hall John E , do Carmo Jussara M
Published: March 2022

Obesity is associated with structural and functional changes in the heart and abnormal cardiovascular responses to exercise in humans and experimental animals. We and others have demonstrated that specific deletion of cardiomyocyte leptin receptors causes cardiac dysfunction associated with decreased energy production in the heart. However, the importance of leptin in normal cardiac reserve during increased stress is still unknown. In this study we examined if leptin deficiency, independently of obesity, alters cardiovascular responses to a stress test induced by dobutamine in 20 week old non-obese ob/ob mice (n=4, 30±2g) that were pair-weighted to match the body weight of wild type (WT) control mice (n=5, 31±3g), and obese ob/ob mice fed ad-lib (n=4, 65±4g). An additional group of non-obese ob/ob mice (n=4) was infused with leptin via osmotic minipump (4 μg/kg/min, IP) for 7 days. Mice were instrumented with for continuous infusion of saline and progressively increasing doses of dobutamine (2-12 ng/g/min, 2 min at each dose). Long and short axis left ventricle dimensions were obtained before and one minute after each dose of dobutamine using a 30 MHZ transducer (VEVO2100®). Baseline heart rate (HR) was similar in obese ob/ob (431±24 bpm) and WT control (421±28 bpm) mice, but significantly reduced in non-obese ob/ob (356±28 bpm) mice. Compared to WT mice, non-obese ob/ob mice had no significantly differences in baseline ejection fraction (EF) (76±4 vs. 66±4%) but higher EF was observed in obese ob/ob (83±3%) mice. Dobutamine infusion increased average delta HR by 42±7, 104±16 and 37±11 bpm, and EF by 24.8±1.2, 4.9±0.5 and 33.3±0.8 % in WT, non-obese ob/ob and obese ob/ob mice, respectively. Chronic leptin replacement restored EF response to dobutamine in non-obese ob/ob mice (93±2 vs. 94±2% in WT mice). These results show that leptin deficiency leads to reduced myocardial reserve independent of changes in body weight, and leptin replacement in non-obese ob/ob mice completely restored EF response to cardiovascular stress test.
Abstract P295: High Dietary Fat Intake Attenuates Pressure Overload-induced Cardiac Remodelling in a Spontaneous Hypertensive Rat Model
Authors: McNamara Eugene , Watson Chris , Shiels Liam , Russell-Hallinan Adam , Ledwidge Mark , Baugh John
Published: March 2022

Heart failure with preserved ejection fraction (HFpEF) is emerging as a metabolic disease. HFpEF initiation and progression is associated with the pro-inflammatory state found in conditions such as hypertension, obesity and diabetes. Although the role of dietary fat in the genesis of metabolic disorders and tissue inflammation has been characterised, dietary fat induced cardiac pathology and inflammation in the context of pressure-overload is less well defined. In this study, we reveal the cardioprotective effects of saturated fat intake on cardiac phenotype and cardiac inflammation in an established rat model of hypertension. Ten week old male normotensive Wistar (WKY), control rats (n=10), and matched SHR (n=20), were split into low-10%kcal and high-45%kcal fat chow. After 16 wks of diet intake, bodyweight profiles were similar among all groups (p=NS). Unconscious tail-cuff plethysmography confirmed elevated arterial pressure (>140mmHg) in both SHR dietary groups, (SBP in 45%kcal; 154.4 ± 21.7 mmHg, p<0.05 and 10%kcal; 151.4 ± 31.5 mmHg, p<NS). Endpoint echocardiography revealed increased LVMi (normalised: tibia length) in 10%kcal, which was ameliorated in 45%kcal (respectively; 24.7 ± 2.2 mg/mm vs. WKY, p<0.05 and 22.5 ± 1.3 mg/mm, vs. WKY, p=NS). Furthermore, anterior wall thickness in both systole and diastole was greater in 10%kcal fed animals (p<0.01 vs. WKY). Left ventricular remodelling was exaggerated in 10%kcal vs. 45%kcal, with significant increases in cardiomyocyte cross-sectional area and collagen deposition (vs. WKY control). In SHR groups, cardiac CD68
+
macrophage infiltration was increased (10%kcal; 122.5 cells/mm
2
, & 45%kcal; 151.1 cells/mm
2
, p<0.05 vs. WKY). Alterations in markers of metabolic dysfunction was evident with increased total cholesterol (10%kcal, 21.7 ± 0.52 mg/dL, p<0.01 vs. WKY and 45%kcal; 22.01 ± 0.83 mg/dL, p<0.001 vs. WKY), and glycated hemoglobin (HbA1c) in high-fat fed rats vs. 10%kcal control (p<0.05). In summary, dietary fat intake may prevent heart failure development, despite cardiac inflammation and dysfunctional metabolism. Collectively, our data show long-term saturated fat intake attenuates pathological cardiac fibrosis and hypertrophy in a rat model of chronic pressure-overload.
Abstract P297: The Deleterious Role of Prostaglandin E2 EP3 Receptor in Ang II-induced Hypertension
Authors: Bryson Timothy , Xu Jiang , Harding Pamela
Published: March 2022

High blood pressure (BP) is a major risk factor for heart and renal disease. Prostaglandin E2 (PGE2) is a product of the arachidonic acid cascade and is known to mediate inflammation and have vasodilatory effects. Previous data from our lab have shown that PGE2 reduces cardiac contractility when signaling through its EP3 receptor subtype and that EP3 expression increases in the left ventricle of mice subjected to Angiotensin II (Ang II) hypertension. We therefore hypothesized that EP3 activation would worsen BP in the Ang II hypertension model and would also decrease cardiac function. To test our hypothesis, we treated 10-12 wk. old C57Bl/6 mice with either Ang II (1.4 mg/kg/d) or vehicle via osmotic mini pump and simultaneously treated them with the EP3 agonist, Sulprostone (80 μg/kg/d, S.C.), or vehicle for 2 weeks. As expected, Ang II infusion increased BP significantly (115 mmHg ± 4.8 vs. 172 mmHg ± 12.1; p< 0.005). After 2 weeks, however, there was no difference in BP between the Ang II group and the Ang II + Sulp. group. Echocardiography in conscious animals demonstrated that treatment with Ang II + Sulp. group reduced shortening fraction (SF) from 61.28 ± 1.82 % to 56.71 ± 0.91 %; (p<0.05) whereas Ang II treatment alone did not affect SF. This suggests that EP3 activation combined with Ang II infusion may reduce cardiac function in as little as 2 weeks. We then repeated this protocol using the EP3 inhibitor, L798, 106 (40 μg/kg/d). Remarkably, the increase in BP with Ang II was almost completely abolished when animals received the inhibitor (168.3 mmHg ± 6.5 for Ang II group vs. 117.9 mmHg ± 17.1 for Ang II + L798, 106 group; p< 0.05) without changes in cardiac function. Since the effects on BP are independent of changes in cardiac function, we hypothesize the effects are on total peripheral resistance and future experiments will examine the vasculature to identify possible mechanism(s). In conclusion, EP3 receptor activation did not worsen BP after Ang II infusion but treatment with the EP3 inhibitor completely normalized blood pressure. This suggests that there is commonality between the EP3 and Ang II signaling pathways. We also propose that EP3 receptor activation is deleterious in an Ang II model since treatment with Sulprostone reduces cardiac function after only 2 weeks.
Abstract P304: Motivia®, a Cardiovascular Disease Prevention Program, Decreases Hospitalization Length in Patients With High Risk for Developing Cardiovascular Event. Retrospective Analysis From 2010-2015
Authors: Perez Hernan A , Jorgensen Natalia , Torales Santiago , Chianalino Andrés , Armando Luis J
Published: March 2022

Objective:
Cardiovascular events (CE) due to atherosclerosis are preventable but the identification of adults at high risk (HR) is required. Burden of atherosclerosis is not considered for categorization of HR patients (HRPts), even though only fractions of CE are predicted by Framingham risk factors (FRS). Our objective was to investigate the effectiveness of a program (Motivia®) designed for detection and monitoring of HRPts in a health insurance program.

Design and Method:
Motivia® is a program where patients are categorized based on the cardiovascular risk score using our previously reported algorithm, FRS combined with the Total Plaque Area (TPA) determination, and treatment is based on the post-test score. In this retrospective analysis (2010-2015) only HRPtes (based on TPA+FRS) were included. After categorization, Pts were referred to Motivia® high risk medical attention physician (MHP) or primary attention physician (PP) to perform evaluation and monitoring. Each Pt was seen at least each 3 months to achieve control of risk factors. The outcome measured were, time to first hospitalization for acute ischemic syndrome, coronary revascularization procedure, stroke, diabetes complication, and heart failure. We used models of survival (Log Rank test and Cox proportional hazards model) for the analysis. Outcome of these 2 groups were compared. Pts signed informed consent and the study was approved by the Blossom DMO Argentina ethics committee.

Results:
The analysis showed a significant reduction in the overall rate of CVE from 1.37% to 1.03% in both groups while in > 64 years old the reduction was greater (from 4.51% to 2.45%). However, after age, sex and pretreatment risk correction, we did not observe difference in the likelihood to have a cardiovascular event. Nevertheless, interms of hospitality length, patients under MHP had shorter stay than PP (2.3 vs. 3.5 days/bed).

Conclusions:
Motivia® program, based on intensive treatment using TPA determination may benefit patients and health insurance by decreasing hospitality length.
Abstract P306: Maternal High Fat Diet Acts on the Brain to Induce Baroreflex Dysfunction and Sensitization of Angiotensin II-induced Hypertension in Adult Offspring
Authors: Zhang Yu-Ping , Huo Yan-Li , Fang Zhi-Qin , Wang Xue-Fang , Li Jian-Dong , Wang Hai-Ping , Peng Wei , Johnson Alan K , Xue Baojian
Published: March 2022

Accumulating evidence indicates that maternal high fat diet (HFD) is associated with metabolic syndrome and cardiovascular disease in adult offspring. The present study tested the hypothesis that maternal HFD modulates the brain renin-angiotensin system (RAS), oxidative stress and proinflammatory cytokines that alters angiotensin II and tumor necrosis factor-α (TNF-α) actions to sensitize the angiotensin II-elicited hypertensive response in adult offspring. All offspring were cross-fostered by dams on the same or opposite diet to yield 4 groups: offspring from normal fat control diet (CD)-fed dams suckled by CD-fed dams (OCC) or by HFD-fed dams (OCH) and offspring from HFD-fed dams fed HFD suckled by CD-fed dams (OHC) or by HFD-fed dams (OHH). RT-PCR analyses of the lamina terminalis (LT) and paraventricular nucleus (PVN) indicated upregulation of mRNA expression of several RAS components, NADPH oxidase and proinflammatory cytokines in 10-week old male offspring of dams fed HFD during either pregnancy, lactation or both (OHC, OCH and OHH). These offspring also showed decreased baroreflex sensitivity and increased pressor responses to intracerebroventricular microinjection of either angiotensin II or TNF-α. Furthermore, chronic systemic infusion of angiotensin II resulted in enhanced upregulation of mRNA expression of RAS components, NADPH oxidase and proinflammatory cytokines in the LT and PVN and an augmented hypertensive response in the OHC, OCH and OHH groups when compared to the OCC. The results suggest that maternal HFD blunts baroreflex function and enhances pressor responses to angiotensin II or proinflammaroty cytokines through upregulation of the brain RAS, oxidative stress and inflammation.
Abstract P310: Atuplex Formulated With Small Interfering RNA For Soluble Fms-like Tyrosine Kinase-1 (sFLT1) Selectively Silences Maternal And Placental sFLT1 In A Preeclamptic Rat Model
Authors: Haase Nadine , Kräker Kristin , Schaeper Ute , Endruschat Jens , Müller Dominik N , Dechend Ralf
Published: March 2022

Preeclampsia is a pregnancy-related disorder characterized by hypertension and proteinuria, affecting about 5-8% of pregnancies. It is a major cause of fetal and maternal morbidity/mortality. The disease is most probably multifactorial and caused by several placental dysfunctions. As an important mediator, sFLT1 is induced in the placenta and in the serum of preeclamptic women, acting as a decoy receptor for placenta like growth factors (PLGF) and inducing an antiangiogenic balance. RNAi mediated gene specific silencing could represent a new therapeutic option in preeclampsia management. We tested sFLT1-specific small interfering RNA (siRNA) formulated with the liposomal siRNA delivery system AtuPLEX for the ability to ameliorate symptoms without deteriorating fetal health in an established rat model of preeclampsia. Transgenic rats expressing human angiotensinogen (hAGT) and renin (hREN) were crossed to produce a model of preeclampsia (PE rat) in the dams. Beginning on day 7 of gestation, transgenic hAGT dams were dosed intravenously with 2.8 mg/kg siRNA every third day through gestational day 19. Mean blood pressure was continuously recorded by radiotelemetry and 24 hour urine samples were collected in metabolic cages at day 17/18 of gestation. Rats were euthanized at day 21 of gestation. Biodistribution experiments showed that sFLT1 siRNA formulated with AtuPLEX delivers siRNA to the placenta but not to the embryo. In PE rats, our treatment was able to decrease sFLT1 mRNA expression in placenta, especially in the labyrinth layer. Circulating sFLT1 was also reduced by FLT1 siRNA treatment but did not show statistical significance. Silencing of sFLT1 did not prevent blood pressure increase in the last third of pregnancy in our preeclamptic rat model (159 ± 5 mmHg vehicle vs. 152 ± 2 mmHg sFLT1 siRNA). Proteinuria was not ameliorated (5712 ± 2038 μg/d vehicle vs. 3585 ± 1301 μg/d sFLT1 siRNA). In addition, sFLT1 siRNA had no influence on IUGR, measured by brain to liver weight ratio. AtuPLEX formulated siRNA specifically silenced maternal and placental sFLT1. The mode of delivery appears to be safe for fetal health. However, this sFLT1 knock down showed no protective effect on the preeclamptic phenotype in this Ang-II-based model.
Abstract P315: Gender Differences of Aortic Wave Reflection and Influence of Menopause on Central Blood Pressure in Patients With Arterial Hypertension
Authors: Costa-Hong Valeria , Muela Henrique C , Macedo Thiago A , Sales Allan R , Bortolotto Luiz A
Published: March 2022

Background:
Evidences suggest that central hemodynamics indexes are independent predictors of future cardiovascular events and all-cause mortality. Multiple factors have been pointed to have potential influence on central aortic function: height, heart rate, left ventricular ejection duration and blood pressure level. Data related to the influence of gender and postmenopausal status on aortic wave form reflection is scarce.

Methods:
In a cross sectional study, 122 hypertensive patients (52 men and 70 women) were studied. Hypertension was defined as blood pressure (BP) levels ≥140/90 mmHg or use of antihypertensive drugs. Central arterial pressure, augmentation index (AIx) and augmentation index normalized to 75bpm (Alx75) were obtained using applanation tonometry. Menopause and postmenopause history were accessed by a direct questionnaire. Postmenopause was defined as at least one year since last menstruation. Patients were paired by age, gender and menopausal status and 4 groups were compared: group 1 (young men, ≤ 48y), group 2 (young women, ≤4 8y), group 3 (older men, > 48y) and group 4 (older women, > 48y).

Results:
Height and weight were significantly lower in women than in men at the same age. Conversely, Alx (32.7±9.8% vs. 20.1±11.7%, p<0.01), Alx75 (29.6±6.7% vs. 18.3±9.4%, p<0.01) and central systolic blood pressure (136±30 vs. 125±23 mmHg, p=0.03) were higher in women than men. The menopausal women had the worst indexes of aortic wave reflection.

Conclusion:
Women patients had both higher reflected aortic pressure wave form and central blood pressure indexes and these findings were worsened by the menopausal status.
Abstract P316: Gonad Dependent Changes in Kallikrein Kinin System Behavior and Renal Electrolyte Excretion After Rectifying Outer Medulla K
+
Channel Blockade in Spontaneously Hypertensive Rats
Authors: Guevara Dario , Oddo Elisabet M , Celìa Alejandro F , Solernó Martin , Di Ciano Luis A , Ibarra Fernando R , Arrizurieta Elvira E , Azurmendi Pablo J
Published: March 2022

The kallikrein kinin system (KKS) is involved in blood pressure (BP) regulation by a mechanism not completely defined. Our previous reports have shown that high K
+
intake or prepuberal gonadectomy (Gx) diminish BP with a simultaneous increase in urine kallikrein activity (UKa) and plasma aldosterone (PA) levels, revealing a link between those systems. Thus, since K
+
may be involved in the regulation of KKS, we explored the rectifying outer medulla K
+
(ROMK) channel blockade using glibenclamide (Gli) in different gonad contexts.Spontaneously hypertensive rats of both sexes, half of them Gx at weaning, were studied at 12 weeks of age (n = 32). Glucose solution (4%) with or without Gli (10 mg/kg bwt) was orally administered in the last 3 days of the experiment. We analyzed BP, glomerular filtration rate, PA, daily urine Na
+
and K
+
excretion and UKa. Renal cortex kallikrein activity (RKa) and UKa were determined by colorimetric assay. Renal mRNA levels of Kcjn1 (ROMK), Atp1α1 (Na
+
K
+
Atpase) and Klk1 (kallikrein 1) genes were determined by quantitative real time PCR. Urine Na
+
/K
+
increased after Gli treatment (0.55 ± 0.03
vs
1.34 ± 0.30,
p
<0.05) due to a K
+
excretion decrease in intact male and ovariectomized rats and to a Na
+
excretion increase in intact female. These changes were concomitant with increased GFR within the normal range (0.51 ± 0.06
vs
0.76 ± 0.06 ml/min/100g bwt
p
< 0.01) and no differences in BP and PA among groups. After Gli treatment, renal cortex Klk1 and RKa levels increased in intact males (297 and 137 %,
p
< 0.05, respectively), while in orchidectomized group Klk1 and UKa levels increased (179 and 230 %,
p
< 0.05; respectively). Kcjn1 and Atp1α1 mRNA levels decreased in renal medulla of all groups (1.29 ± 0.28
vs
0.32 ± 0.11 and 0.94 ± 0.23
vs
0.20 ± 0.02,
p
< 0.01, respectively). Taken together, gonad dependent changes were seen in urine Na
+
and K
+
excretion and KKS behavior after ROMK blockade without changes in the BP and aldosterone. Moreover, the repression in Kcjn1 and Atp1α1 genes could be related to the observed ion transport changes.
Abstract P318: Signaling Pathways Triggered by the Mas Receptor
Authors: Burghi Valeria , Echeverria Emiliana B , Quiroga Diego T , Munoz Marina C , Fernandez Natalia C , Dominici Fernando P
Published: March 2022

Mas receptor (MasR) is a class A Orphan G-protein-coupled receptor (GPCR). Although angiotensin-(1-7) [Ang-(1-7)] has been reported as its putative ligand, the intracellular signaling pathways activated by the MasR remain only partially characterized. In this study we examined MasR-dependent activation of G protein-mediated and ERK mediated signaling pathways. With that aim in human lung carcinoma A549 cells we evaluated Gq-coupled activity by monitoring changes in intracellular Ca
2+
levels after Ang(1-7) stimulation. Incubation with 100nM Ang-(1-7) failed to increase Ca
2+
levels either in endogenously expressing or MasR overexpressing A549 cells. On the other hand, transfection of HEK293T cells with a wild-type MasR (wt-MasR) construct resulted in a significant decrease in basal cAMP levels (p<0.05) that depended on the amount of wt-MasR protein expressed but was not observed when increasing amounts of mutant MasR lacking the PDZ binding motif were expressed. Pretreatment of wt-MasR expressing cells with pertussis toxin restored basal cAMP levels (p<0.05) whereas no effect was observed in mock-transfected cells. Also, cAMP production after forskolin stimulation was lower in cells expressing wt-MasR than in control cells. These results indicate a high level of constitutive receptor activity towards cAMP modulation involving Gαi-protein. Treatment with Ang-(1-7) increased p-ERK levels in a concentration-dependent manner in both wt-MasR and in mock-transfected HEK293T cells. In view of these results we are analyzing whether ERK activation is mediated through Ang-(1-7) binding to endogenously expressed receptors different from MasR. As MasR has been suggested to participate in cardiovascular and renal functions, comprehensive pharmacological characterization of MasR signaling is essential for developing clinical therapeutics targeting MasR function.
Abstract P325: 6β-hydroxytestosterone, a Cytochrome P450 1B1 Metabolite of Testosterone, Contributes to Angiotensin II-Induced Abdominal Aortic Aneurysms in Hyperlipidemic Male Mice
Authors: Mukherjee Kamalika , Pingili Ajeeth K , Dhodi Ahmad N , Malik Kafait U
Published: March 2022

It is well established that men have a higher risk of developing cardiovascular diseases including hypertension and abdominal aortic aneurysms (AAAs) than do premenopausal women of the same age. Angiotensin II (Ang II) induces abdominal aortic aneurysms (AAA) to a greater degree in male than in female mice, and castration protects male mice against Ang II-induced AAAs. Previously we reported that cytochrome P450 (CYP) 1B1 contributes to Ang II-induced hypertension as well as AAAs in male mice. Recently we have shown that CYP1B1-testosterone derived metabolite 6β-hydroxytestosterone (6β-OHT), mediates Ang II-induced hypertension and cardiac and renal fibrosis in male mice. The current study was conducted to determine the contribution of CYP 1B1-generated 6β-OHT to Ang II-induced AAAs in male mice. Sixteen-week old intact or castrated male,

ApoE
-/-
/ Cyp1b1
+/+

(ApoE KO) and

ApoE
-/-
/ Cyp1b1
-/-

(DKO) mice were infused with 700 ng/kg/min Ang II or its vehicle (s.c.) with osmotic minipumps for 28 days. These mice were also injected with 6β-OHT (15 μg/g body weight, i.p. every 3rd day) or its vehicle for the duration of the experiment. The abdominal aortas were analyzed for development of AAAs (a 50% increase in external abdominal aortic diameter). Ang II significantly increased (
P
<0.05) the incidence as well as severity of AAAs in intact ApoE KO mice (66.7% incidence; 8 of 12), compared to 0% (0 of 5) incidence in vehicle-treated mice, which were minimized in castrated ApoE KO (0% incidence; 0 of 9) and intact DKO (0% incidence; 0 of 9) mice. Administration of 6β-OHT restored the incidence and severity of AAAs in Ang II-infused castrated ApoE KO (44.4% incidence; 4 of 9) and intact DKO (62.5% incidence; 10 of 16) mice. In contrast, treatment with testosterone failed to increase the incidence and severity of Ang II-induced AAAs in the intact DKO mice (10% incidence; 1 of 10). Histological analysis of sections of the abdominal aortas confirmed the above results, along with disruption of elastin fibers, a pathological hallmark of AAAs. These data suggest that CYP1B1-generated testosterone metabolite, 6β-OHT, contributes to Ang II-induced AAAs in hyperlipidemic male mice. Therefore, inhibitors of CYP1B1 could be useful in the treatment of AAAs in males with hyperlipidemia.
Abstract P329: Sympathetically Alpha-1 Adrenoceptor Mediated Regulation of the NCC in Rat Models of Salt Sensitive and Neurogenic Hypertension
Authors: Wainford Richard D , Frame Alissa A
Published: March 2022

Hypothesis:
Excess SNS release of norepinephrine (NE) increases NCC activity, via an α1 adrenoceptor pathway, to drive the development and maintenance of salt-sensitive and neurogenic hypertension (HTN).

Methods:
Male Sprague-Dawley (SD) rats receiving a continuous s.c. saline or NE (600ng/min) infusion alone or in combination with terazosin (10mg/kg/day) were fed a 14-day 0.6% (NS) or 4% NaCl (HS) diet. Separate groups of male SD rats received a continuous s.c. NE infusion and 28-day NS or HS intake, on day 14 of HS a sub group of rats were switched to a co NE-terazosin s.c. infusion. Groups of male SHR rats received s.c. saline or terazosin for 14 days. Endpoint measurements (day 14 or 28) were basal MAP and NCC activity (peak natriuresis to iv hydrochlorothiazide (HCTZ; 2mg/kg) infusion and phosphoNCCT58 immunoblotting) and expression (via immunoblotting) was assessed (N=4/gp).

Results:
NE infused SD rats exhibit HTN and fail to suppress NCC expression and activity during HS-intake. α1-adreoceptor antagonism (confirmed pharmacologically) abolished the salt-sensitive component of NE HTN and restored dietary sodium evoked suppression of the NCC in NE infused SD rats. Critically, α
1
-adrenoceptor antagonism lowers BP and reduces NCC activity in established SHR HTN and restores sodium-evoked suppression of NCC activity and abolishes the salt sensitivity of BP in established NE-evoked SS HTN.

Conclusion:
SNS activation of the NCC by NE occurs in rat models of neurogenic and SS HTN. Our data demonstrates antagonism of α
1
-adrenoceptors lowers BP and NCC activity in established SS and neurogenic HTN and suggests α
1
-antagonists as a therapeutic option in sympathetically mediated HTN.