bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 630: Differential Renal And Cardiac Effects Of Nox4 In Chronic Angiotensin II-Dependent Hypertension
Authors: Majane Olebogeng H , Callera Glaucia E , He Ying , Antunes Tayze T , Gutsol Alex , Montezano Augusto C , Brandes Ralf P , Schröder Katrin , Kennedy Christopher R , Touyz Rhian M
Published: March 2022

A role for Nox4 in hypertension remains in question. Both protective and injurious Nox4-dependent renal and cardiovascular effects have been reported. We assessed whether gene-targeted Nox4 deficiency (Nox4
-/-
mice) could affect development of hypertension, cardiac hypertrophy and renal function in a model of chronic angiotensin II (AngII)-dependent hypertension. We studied mice transgenic for active human renin under the control of the transthyretin promoter (LinA3 mice); these mice develop hypertension over the course of their lifespan. Four genotypes of mice were generated: Wild-type (WT), LinA3, Nox4
-/-
, and LinA3/Nox4
-/-
. Nox4-deficiency prevented the development of hypertension (LinA3: 154 vs LinA3/Nox4
-/-
: 135 mmHg) and cardiac hypertrophy (LinA3: 2.55 vs LinA3/Nox4
-/-
: 1.73 mg/g) observed in LinA3 mice (
P
<0.05) and was associated with reduced systemic oxidative stress (Plasma TBARS - LinA3: 2.13 vs LinA3/Nox4
-/-
: 1.71 mM)
.
Furthermore, cardiac collagen content was decreased in Nox4
-/-
versus LinA3 mice. While Nox4 deficiency attenuated hypertension in LinA3 mice, it yielded detrimental effects on renal function. Specifically, albumin-to-creatinine ratio was significantly elevated in LinA3/Nox4
-/-
mice compared with LinA3, Nox4
-/-
and WT littermates. LinA3 mice showed evidence of mild segmental glomerulosclerosis. LinA3/Nox4
-/-
mice developed severe renal lesions including increased glomerular tuft to fibrotic area, global glomerulosclerosis

with numerous foci containing perivascular and peritubular monocyte/macrophage cell infiltration. These findings demonstrate that while global Nox4 deletion may be protective for cardiac pathology and hypertension it is conducive to renal injury in a model of chronic AngII-mediated hypertension. Our data indicate tissue-specific effects of Nox4, which may explain divergent renal and cardiac Nox4 actions in Ang II-dependent hypertension.
Abstract 638: Autonomic Cardiovascular Control Responses To Inspiratory Muscle Training And Aerobic Training In Hypertensive Patients
Authors: Ferreira Janaina B , Santos Fernando , Coelho Otávio , Dal Lago Pedro , Consolim-Colombo Fernanda , Irigoyen Maria Cláudia C
Published: March 2022

Arterial hypertension is characterized by autonomic cardiovascular control imbalance, especially by sympathetic hyperactivity and reduction of vagal modulation. Aerobic training (AT) is highly recommended and Inspiratory muscle training (IMT) has demonstrated beneficial effects in this population as well. We sought to observe the effects of both training modalities in patients with controlled arterial hypertension. 13 patients (55±4 years old, both genders) were included and allocated in three groups: IMT (n=4, 7days/week, 30min/day, load=30%PImax), AT (n=4, 2days/week, 1hour/day, load=70%HRmax) and Control (n=5). Training protocols were performed during 12 weeks. Blood pressure (BP) and heart rate (HR) signals were recorded before and after protocols by pulse telemetry (Finometer®PRO) and ECG (PowerLab®). Autonomic cardiovascular control components were evaluated in time and frequency domains and arterial baroreflex function was analysed by sequence method. The analysis of blood pressure variability components demonstrated that IMT reduced time domain BP Variability (BPV) (SD: IMT=5.52(±3.04)vs11.93(±7.27)mmHg, AT=8.23(±1.8)vs5.16(±1.8)mmHg) as well as sympathetic component of BPV (LFabs: IMT=4.4(2.55)vs10.09(±9.64)mmHg
2
; AT=7.15(±4.13)vs6.27(±2.03)mmHg
2
). In relation to HR variability components, we observed increase of vagal modulation after IMT (HFun: IMT=71.75(13.9)vs65.26(±36.2), AT=55.75(10.07)vs60(15.9)) probably leading to benefits in simpathovagal balance in this group (LH/HF: IMT=0.51(±0.2)vs2.22(±0.4), AT=1.2(±0.5)vs0.96(±0.5)). Additionally, the IMT improved baroreflex sensitvity to both Tachycardic and bradycardic responses respectively (BRR Down Gain (mean): IMT=26.51(±1.7)vs15.57(±6.7), AT=13.94(±5.5)vs17.92(±1.6); BRR Up Gain (mean): IMT=17.16(±1.2)vs16.28(±1.1), AT=12.39(±5)vs12.69(±3.3)). Our results demonstrate, for the first time that in spite of AT beneficial effects on control and BP levels, inspiratory muscle training might improve importantly cardiopulmonary interaction in hypertension, with even more clear benefits on autonomic cardiovascular control.
Abstract 647: Histone Deacetylase 1 Reduces No Production In Endothelial Cells Via Lysine Deacetylation Of No Synthase 3
Authors: Hyndman Kelly , Ho Dao , Sega Martiana , Pollock Jennifer
Published: March 2022

The lysine acetylation state of non-histone proteins may be regulated through histone deacetylases (HDACs). Evidence suggests that NO synthase 3 (NOS3; eNOS) is post-translationally lysine acetylated leading to increased NO production in the endothelium. The purpose of this study was to test the hypothesis that NOS3 is lysine-acetylated and that upregulated HDAC1-mediated deacetylation leads to reduced NO production in endothelial cells. We determined that NOS3 is basally lysine acetylated in cultured bovine aortic endothelial cells (BAECs). In BAECs, HDAC1 is expressed in the nucleus and cytosol, and forms a novel protein-protein interaction with NOS3. Overexpression of HDAC1 in BAECs resulted in a significant reduction in NOS3 lysine acetylation (control = 1.0 ± 0.1, HDAC1 = 0.59 ± 0.08 A.U., P < 0.01), while HDAC1 knockdown with siRNA resulted in no significant change in NOS3 acetylation level. Moreover, overexpression or knockdown of HDAC1 resulted in no significant effect on NOS3 protein expression or on expression levels of NOS3 phosphorylation sites T497, S635, S1179. HDAC1 overexpression in BAECs significantly blunted basal nitrite production (an index of nitric oxide production; control 287.7 ± 29.1 pmol/mg p/h, HDAC1 172.4 ± 31.7 pmol/mg p/h, P < 0.05) as well as attenuating endothelin-1 stimulated nitrite production (control 481.8 ± 50.3 pmol/mg/h, HDAC1 243.1 ± 48.2 pmol/mg/h, P< 0.05). On the contrary, HDAC1 knockdown increased basal nitrite production (730.6 ± 99.1 pmol/mg/h), and further exaggerated increases in endothelin-1 stimulated nitrite production (1276.9 ± 288.2 pmol/mg/h). Thus, these data indicate that up-regulated HDAC1 decreases NOS3 activity, most likely, through direct lysine deacetylation of NOS3. We propose that HDAC1-mediated deacetylation of NOS3 may represent a novel target for endothelial dysfunction.
Abstract 651: Toll-like Receptor 4 (TLR4) Suppresses Nitric Oxide Contributing To AngiotensinII-induced Cavernosal Dysfunction.
Authors: Nunes Kenia Pedrosa , Bomfim Gisele , Carrilo-Sepulveda Maria Alicia , Szasz Theodora , Webb R. Clinton
Published: March 2022

AngiotensinII (AngII) is an important regulator of erectile dysfunction (ED), a vascular condition which has been described as an early marker for cardiovascular diseases. Recent evidence shows AngII modulates the expression of TLR4, resulting in augmented tumor necrosis factor α (TNF-α) cytokine associated to ED and nitric oxide synthase (NOS) suppression, effects that directly impact the vasculature. We investigate whether TLR4 plays a role in cavernosal dysfunction caused by AngII. Mice were infused with AngII (90ng/min, 28 days) in the presence or absence of anti-TLR4 antibody (0.1 mg/daily, i.p.) for the last 14 days. After blood pressure evaluation, corpus cavernosum (CC) tissue was used for functional studies and western blot. NOS activity was measured by conversion of [3H]-L-arginine to [3H]-L-citrulline and systemic TNF-α levels by ELISA. In AngII-infused mice increased adrenergic CC contraction was attenuated by blocking TLR4 (28±2.1%), which also ameliorated nitrergic (68.90±0.21 vs. 51.07±0.63, 8Hz) and endothelium-dependent relaxation (4.90±0.13 vs 2.45±0.19, AngII-infused mice treated vs. non-treated). Reduced NOS activity, augmented systemic levels of TNF-α and this cytokine overexpression were found in CC following AngII-infusion. However, these alterations were prevented by blocking TLR4, suggesting that inhibition of TLR4 ameliorates AngII-impaired cavernosal relaxation and restores NO availability, which is vital for normal penile erection and vascular function. Our data provides new insights into understanding the mechanisms leading to hypertension-associated ED.
Abstract 653: Stimulation Of Endothelial Nitric Oxide Production And Dilation By The G Protein-coupled Estrogen Receptor
Authors: Fredette Natalie C , Meyer Matthias R , Prossnitz Eric R
Published: March 2022

Endogenous estrogens mediate protective effects in the cardiovascular system in part due to rapid activation of endothelial nitric oxide synthase (eNOS), which involves the classical estrogen receptor (ER) α. Estrogen-dependent increases in NO bioactivity may also be mediated by the G protein-coupled estrogen receptor (GPER/GPR30), although the contribution of GPER to the overall response to estrogen and the mechanisms involved remain unclear. We have investigated GPER-mediated NO signaling in telomerase-immortalized human umbilical vein endothelial (TIVE) cells as well as estrogen-dependent, GPER-mediated relaxation in mouse aortae. Similar to the non-selective ER agonist 17β-estradiol (E2), the GPER-selective agonist G-1 stimulated phosphorylation of eNOS (ser1171) at 100 nM vs. 0.01% DMSO vehicle (53 +/-7 vs. 19+/-4, p=0.035, n=4). Colorimetric detection of nitric oxide demonstrated that Acetylcholine (Ach) (536 +/-18), E2 (425+/- 18) and G-1 (308 +/-18) also increased NO production in TIVEs (vs. veh 94.0 +/-5, p= 0.006, n=4-6). Pharmacologic inhibition of GPER (G36) reduced NO production in response to E2 by 57% (407 +/-29 vs. 235 +/- 15, p=0.009, n=6), but not to Ach (543+/-12 vs. 533+/-9, p=0.838, n=5-8). In contrast, inhibition of EGFR signaling with AG1478 did not reduce GPER-mediated (G-1) eNOS phosphorylation or G-1-induced NO production (172 +/-8 and 201 +/-12, p=0.120, n=3). Myography studies of endothelium-intact aorta from GPER KO showed a 46% reduction in the relaxation response to E2 compared to WT (-32.3 +/-8.1% and -59.2 +/-3.2 %, p=0.009, n=4-5). Relaxation responses to Ach were similar in GPER KO and WT (-88.0 +/- 1.2 mg and -90.6 +/-1.4 mg, p=0.204, n=5), and WT aorta showed similar relaxation to both E2 and G-1 (59.2 +/- 3.21% and 62.03 +/-6.24%, p=0.71, n=7). These findings suggest that in addition to ERα, the activity of GPER is likely required for full eNOS activation and vasodilation in response to E2, and thus may contribute to the estrogen-mediated protective effects in the cardiovascular system.
Abstract 661: Foxo3 Genotype Increases Lifespan By A Major Effect On Cardiovascular Mortality
Authors: Morris Brian J , Willcox Bradley J , Chen Randi , Masaki Kamal H , He Qimei , Grove John S , Willcox D. C , Allsopp Richard , Moisyadi Stefan , Poon Leonard W , Donlon Timothy A
Published: March 2022

The strongest, most consistently replicated genetic influences on human lifespan worldwide involve specific alleles of the ApoE and Foxo3 genes. For
FOXO3
, the
G
allele of SNP
rs2802292
exhibits the most robust association. The aim of the present study was to determine
FOXO3
genotype-related cause-specific mortality over 9 years in 3,584 elderly American men of Japanese ancestry from the Kuakini Hawaii Lifespan Study, an extensively characterized, long-studied, robust cohort drawn from the Honolulu Heart Program, which recruited subjects in 1965–1968. A Cox proportional hazards model computed relative risk of mortality for coronary heart disease (CHD), cancer, stroke, other circulatory diseases, and remaining causes. We created multivariate models that included other major risk factors for all-cause and cause-specific mortality. We determined contribution of
FOXO3
genotype and other risk factors to mortality by estimating population attributable risk over 9 years follow-up for cause-specific mortality, and total mortality over 21 years. The survival curve, age standardized at 78 years (mean subject age at baseline), for carriers and non-carriers of the longevity-associated
G
allele showed that
G
allele carriers had longer survival (
P
=0.016) during follow-up over 9 years (1,272 total deaths), and 21 years (
P
=0.004; 3,211 total deaths). Over the 9 years, the 1,683 carriers of the
G
allele exhibited risk reductions of 16% (RR 0.84, 95% CI 0.74–0.95;
P
=0.008) for all-cause mortality, 41% (RR 0.59, 95% CI 0.43–0.80;
P
<0.001) for CHD mortality (202 deaths) and 21% (RR 0.79, 95% CI 0.67–0.94;
P
=0.009) for 535 deaths from causes besides CHD, cancer or stroke, independent of other major risk factors. Population attributable risk for the
TT
non-protective genotype was 24% for 9-year CHD mortality, 24% for hypertension, 21% for diabetes, 18% for inflammation and 12% for hypercholesterolemia. In conclusion, the
G
allele of the
FOXO3
SNP
rs2802292
has a major effect on mortality, principally through reduction in CHD risk, independent of known major risk factors. The findings support research on
FOXO3
as a target for therapeutic intervention in healthy aging.
Abstract 664: Increased Endothelial Expression of NADPH Oxidase-p47phox in Human Hypertension
Authors: Solow E. B , Danesh Shahab M , Onwuegbuchu Erica , Velasco Alejandro , Raheja Prafull , Arbique Debbie , Wang Zhongyun , Price Angela L , Mineo Chieko , Vongpatanasin Wanpen
Published: March 2022

Introduction:
Hypertensive patients have impaired endothelial-dependent vasodilation. Endothelial nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p47 subunit (p47phox) may contribute to hypertension (HTN) via generation of reactive oxygen species. NADPH oxidase derived superoxide has been shown to inactivate nitric oxide, a potent vasodilator produced by endothelial nitric oxide synthase (eNOS) in endothelial cells (EC), causing endothelial dysfunction. EC expression of p47phox and eNOS in human HTN has not been previously assessed.

Methods:
We assessed endothelial function in 20 Stage 1 hypertensive subjects (mean age 50 years, 55% female) and 18 normotensive (NT) controls (mean age 47 years, 68% female) by brachial artery flow mediated dilation (FMD) and extracted venous EC by J-wires via forearm catheters. Expression of p47phox, eNOS, and phosphorylated eNOS at serine 1177 residue (peNOS) was captured by immunofluorescence microscopy using human umbilical vein endothelial cell (HUVEC) controls.

Results:
FMD was lower in hypertensive compared to NT subjects (6.3±0.6 versus 8.5±1.0 %, p < 0.05). In EC, expression of eNOS and p47phox was greater in hypertensive compared to NT subjects (0.52±0.07 vs 0.32±0.03, p=0.02) and (0.38±0.03 vs 0.27±0.03, p=0.003), respectively, Figure 1. PeNOS was not different between groups. In EC, p47phox expression significantly correlated with blood pressure after adjustment for body mass index (r = 0.39, p = 0.02).

Conclusion:
We found impaired endothelial function and enhanced EC expression of NADPH oxidase p47 subunit, the major oxidant enzyme responsible for vascular superoxide formation, in human hypertension.
Abstract 666: RNAi Therapeutics Targeting Human Angiotensinogen (hAGT) Ameliorate Preeclamptic Sequelae in an Established Transgenic Rodent Model for Preeclampsia
Authors: Haase Nadine , Foster Don , Bercher Julia , Milstein Stuart , Golic Michaela , Charisse Klaus , Rugor Julianna , Kuchimanchi Satya , Przybyl Lukasz , Bettencourt Brian , Müller Dominik N , Hinkle Greg , Dechend Ralf
Published: March 2022

Preeclampsia, a disorder with the hallmark features of new-onset hypertension and proteinuria beginning after 20 weeks of gestation, affects 5% of pregnancies in industrialized nations. It is a major cause of fetal and maternal morbidity/mortality. Several studies have demonstrated that angiotensinogen is involved in the pathogenesis of the disease; however, treatment with ACE Inhibitor or AT1 Receptor blocker is contraindicated due to fetal toxicity.

RNAi therapeutics are highly potent mediators of gene-specific silencing. We tested a human angiotensinogen (hAGT)-specifc siRNA, conjugated to triantennary GalNAc, for the ability to ameliorate symptoms of preeclampsia in an established rat model, without affecting the fetus. Transgenic rats expressing hAGT and human renin (hREN) were crossed to produce a model of preeclampsia (PE rat) in the dams. Beginning on day 3 of gestation, transgenic hAGT dams were dosed subcutaneously with 10 mg/kg siRNA every third day through gestation day 15. Mean blood pressure was continuously recorded by radiotelemetry and 24 hour urine samples were collected in metabolic cages at day 18 of gestation. Rats were euthanized at day 21 of gestation.

Treatment with the GalNAc-conjugated siRNA reduced the spike in blood pressure seen on gestation day 13 and lasted through study termination (MAP on day 16 of gestation: 155.1 ± 1.4 mmHg untreated vs. 138.4 ± 1.8 mmHg treated). Proteinuria was ameliorated (21.7 ± 3.1 mg/d untreated vs. 2.7 ± 0.6 mg/d treated) and levels of agonistic autoantibodies against the angiotensin receptor AT1 were reduced below the limit of detection. Fetal and uteroplacental unit weights increased with RNAi therapy, demonstrating a reduction in intra-uterine growth restriction (brain to liver ratio (0.95 ± 0.04 untreated vs. 0.73 ± 0.02 treated). mRNA levels of hAGT were reduced to background levels in the liver, but were not affected in the placenta, which is of fetal origin.

Our data show that an RNAi therapeutic targeting hAGT ameliorates the clinical sequelae of preeclampsia in a transgenic rat model and improves the outcome of the fetus.
Abstract 667: The Effects of a High-Fat Diet (HFD) on Blood Pressure in Pregnant Rats
Authors: Palei Ana C , Spradley Frank T , Granger Joey P
Published: March 2022

While obesity is a major risk factor for preeclampsia (PE), the mechanisms whereby obesity increases the risk for developing pregnancy-induced hypertension are unclear. Since blood pressure regulation during gestation relies greatly on the nitric oxide (NO) system, we aimed to determine the effects of a HFD on blood pressure and fetal outcomes in pregnant rats treated with NG-nitro-L-arginine methyl ester (L-NAME), a non-specific inhibitor of NO synthases. Twelve-week-old Sprague-Dawley female rats were fed a normal diet (ND, 13% fat kcal) or a HFD (40% fat kcal) ad libitum. Body weight (BW) and total fat mass (FM, measured by EchoMRI) were recorded weekly. After 9 weeks of diet treatment, rats were allowed to breed. On gestation day (GD) 14, L-NAME at the concentration 100 mg/L was added to the drinking water of a sub-group of animals (ND + water, n=5; ND + L-NAME, n=6; HFD + water, n=18; HFD + L-NAME, n=16). On GD 19, mean arterial pressure (MAP) was assessed consciously via carotid catheters. Animals were then euthanized and tissues were harvested. Initial BW and FM were similar in ND + water, ND + L-NAME, HFD + water, and HFD + L-NAME (BW: 239.5±4.1 vs. 241.2±4.8 vs. 238.2±2.5 vs. 241.4±2.5 g and FM: 20.4±2.9 vs. 17.9±2.2 vs. 18.2±1.8 vs. 17.4±2.0 g, respectively). By the end of the study, HFD had no effects on BW and FM in pregnant rats (BW: 472.3±5.2 vs. 468.0±10.1 vs. 461.6±12.2 vs. 462.4±8.9 g and FM: 97.5±2.4 vs. 87.3±9.3 vs. 103.3±7.3 vs. 97.5±6.0 g, respectively). Although MAP was elevated in L-NAME treated pregnant rats, HFD did not alter MAP or exacerbate the effect of L-NAME on MAP (106.6±5.0 vs. 131.3±4.9 vs. 116.0±2.7 vs. 130.2±2.8 mmHg, respectively; P<0.05). Neither HFD nor L-NAME affected litter size (13.0±0.8 vs. 13.2±1.2 vs. 12.0±1.0 vs. 12.1±0.8 number of fetuses per rat, respectively). However, HFD reduced fetal weight equally in water and L-NAME treated pregnant rats (2.2±0.0 vs. 2.2±0.1 vs. 2.1±0.0 vs. 2.0±0.0 g, respectively; P<0.05). In summary, while HFD had a detrimental effect on fetal weight, it had no effect on blood pressure regulation during pregnancy.
Abstract MP02: Central Tumor Necrosis Factor-alpha Induces Sensitization Of Angiotensin II-elicited Hypertension
Authors: XUE BAOJIAN , GUO FANG , YU YANG , BELTZ TERRY G , FELDER ROBERT B , JOHNSON ALAN K
Published: March 2022

Proinflammatory cytokines such as tumor necrosis factor (TNF)-α play an important role in regulating autonomic and cardiovascular function in hypertension. Angiotensin (Ang) II can upregulate proinflammatory cytokine signaling in the brain. Our previous studies using an Induction-Delay-Expression experimental design demonstrated that pretreatment with a subpressor dose of Ang II modifies the brain to produce a sensitized response to a subsequent treatment with a pressor dose of Ang II. The present study tested the hypothesis that brain TNF-α signaling contributes to Ang II-induced sensitization. Male rats were prepared for telemetry recording of BP and were treated during Induction with 1) a peripheral subpressor dose of Ang II (10 ng/kg/min, SC) or 2) peripheral subpressor Ang II plus the TNF-α synthesis inhibitor pentoxifylline (10 μg/h, ICV) or 3) TNF-α (20 ng/d, ICV) for one week. After one week Delay, rats were treated during Expression with Ang II (120 ng/kg/min, SC) for 2 weeks. Rats that received the subpressor Ang II pretreatment responded with enhanced hypertension to Ang II (Δ44.5±3.4 mmHg vs. Δ25.4±2.8 mmHg). Induction with TNF-α or the TNF-α synthesis inhibitor mimicked or abolished sensitization produced by the subpressor dose of ANG II (Δ42.8±5.3 mmHg and Δ28.2±1.9 mmHg), respectively. RT-PCR analysis of tissue from the lamina terminalis indicated that subpressor Ang II or TNF-α given during Induction up-regulated mRNA expression of several renin-angiotensin system components and proinflammatory cytokines including renin, angiotensin converting enzyme, interleukin (IL)-1β and IL-6. The results indicate that Ang II-induced sensitization of Ang II hypertension depends on central proinflammatory cytokine-mediated effects.
Abstract MP03: Intracerebroventricular Administration Of Autologous Bone Marrow-derived Cells Attenuate Inflammation And Increase In AT1 Receptor In The Brain Of Angiotensin II Initiated Hypertensive Rats
Authors: Yamazato Masanobu , Nakamura Takuto , Ishida Akio , Yamazato Yoriko , Ohya Yusuke
Published: March 2022

Objectives:
Bone marrow-derived cells (BMCs) include mesenchymal stem cells (MSC) play critical role in repairing damaged tissue and anti-inflammation. We reported that intracerebroventricular (icv) administration of autologous BMCs attenuate slow pressor Ang II initiated hypertension via attenuating Ang II mediated sympathetic activation in rats. However, mechanisms of this observation have not been elucidated. We hypothesized that BMCs in the brain would attenuate inflammation and modulate overactive renin angiotensin system (RAS) in the brain of Ang II initiated hypertensive rats. Therefore we examined characteristics of BMCs prepared with identical cultural condition to previous experiment and examined expression of inflammation related cytokines and RAS component in the brain of Ang II initiated hypertensive rats.

Methods:
Aspirated bone marrow cells underwent red blood cell lysis protocol were seeded in an individual dish in Dulbecco Modified Eagle Media with 10% fetal bovine serum. Floating cells were removed and plastic adherent cells were allowed to glow for 3 weeks at passage 3. The number of BMCs proliferated more than 10
6
were used for immunocytochemical, flowcytometric, BrdU uptake, and Western blot analysis. TGF-beta, IL-10 and AT1 receptor protein expression were examined in brains of Ang II initiated hypertensive rats.

Results:
Cultured BMCs expressed CD29, a marker of mesenchymal stem cell. Flowcytometric analysis revealed that 38% of BMCs were CD29+ CD34-. Endothelial cell (EC) proliferation assay exhibited 52% higher BrdU uptake with conditioned media from BMCs than the media from ECs. Expression of angiotensin converting enzyme (ACE) was 87% lower in BMCs than in ECs, whereas ACE2 expression was 142% higher in BMCs. Furthermore, Ang II infusion significantly increased expression of TGF-beta and AT1 receptor in the brain by 146% and 135% respectively and icv administration of BMCs attenuated the increases of both expressions (39%, 59% respectively). Ang II infusion with or without BMCs icv did not affect to IL-10 expression in the brain.

Conclusion:
BMCs in the brain may have protective role against Ang II induced sympathetic activation via attenuation of brain inflammation and increase in AT1 receptors.
Abstract MP08: Perivascular Adipose Tissue Reduces Acetylcholine Relaxation In Femoral Artery From Obese Mice
Authors: Sponton Amanda C , Sousa Andressa S , Trifone César B , Delbin Maria A
Published: March 2022

Obesity causes serious metabolic derangements and is closely related to high risk of cardiovascular disease. The role of perivascular adipose tissue in vascular function has recently been recognized. The aim of this study was to investigate the role of perivascular adipose tissue in the vascular responsiveness of femoral artery in obese mice. Male mice (C57BL6/JUnib; body weight: 20.5±0.5) were divided into: control (CT, n=5) and obese (OB, n=5). During 16 weeks the CT mice were fed with standard chow and to induce obesity the OB mice were fed with high fat diet. Concentration-response curves to acetylcholine (ACh), sodium nitroprusside (SNP), phenylephrine (PHE) and thromboxane A2 analog (A2) were obtained in femoral arteries in the absence (PVAT-) or presence (PVAT+) of perivascular adipose tissue. The potency (pEC50) and maximal responses (EMAX) were calculated. The glycaemia and serum total cholesterol were measured. As expected, in OB group the body weight (46±0.9 g), epididymal fat pad (1.4±0.07 g), glycaemia (157±9 mg/dl) and total cholesterol (226±45 mg dl) were increased when compared to CT (28±1 g, 0.3±0.03 g, 98±0.5 mg/dl and 80±4 mg/dl; respectively). The amount of perivascular adipose tissue in femoral rings was markedly increased in OB (2.83±0.64 mg/mm) when compared to CT (0.14±0.02 mg/mm). The PVAT+ did not modify the relaxation response to ACh in CT group. However in OB mice the rings PVAT+ showed a reduction in pEC50 (PVAT+:6.58+0.2 and PVAT-:7.24±0.1; approximately 4.6 fold) and in EMAX to ACh. The relaxation responses to NO donor, SNP, were not modified in all groups. The PVAT+ did not change the response to PHE in all groups. Interestingly in OB group the EMAX to PHE was increased when compared to CT, in rings PVAT- and PVAT+. Neither the pEC50 nor EMAX were modified to U46619 in all groups. In conclusion, the presence of perivascular adipose tissue causes endothelial dysfunction in femoral artery from obese mice.
Abstract 003: Selective Splenic Denervation Inhibits the Egression of T Cell From Spleen, Induced by Angiotensinii, and Protects From Hypertension
Authors: Carnevale Daniela , Perrotta Marialuisa , Pallante Fabio , Fardella Valentina , Iacobucci Roberta , Cutrone Antonella , Lembo Giuseppe
Published: March 2022

It has been elucidated that immunity plays a role in both etiology and target organ damage of hypertension (HTN) induced by different stimuli (AngII, salt, etc.). In the very last year, we found that AngII activates a neuroimmune pathway, passing through the celiac ganglion (CG). Here, we aimed at dissecting this neuroimmune drive, in order to examine the specific role of splenic sympathetic nerve activity (SSNA) in the onset of HTN.

We tested the hypothesis that chronic AngII infusion activates SSNA, in order to recruit T cells. In splenic nerve bundles, we recorded SSNA with a bipolar electrode in mice infused with AngII for 3 days (before BP increase) or with vehicle. SSNA was higher in AngII mice, as compared to vehicle (355±18 vs 141±24 spikes/10min) (p<0.001). We next selectively denervated splenic nerve (SDN) by thermoablation, in order to evaluate whether the AngII-induced increase in SSNA could be detrimental for activation of immunity and onset of HTN. We confirmed the efficacy of SDN by injecting a retrograde neurotracer in the spleen, which was effective in labeling the CG neurons only in sham mice and not in SDN. Furthermore, the tyrosine hydroxylase innervation in the splenic artery of SDN mice was reduced as compared to sham, as well as noradrenaline content in the spleen (sham: 1000±274 vs SDN: 172±44 pg/mg tissue, p<0.01). After 28 days from AngII infusion, SDN mice were protected from HTN as compared to sham (SBP: 107±2 vs 129±3 mmHg) and vehicle treated mice (veh-sham 110±1 vs veh-SDN 106±1 mmHg) (p<0.001). Moreover, SDN hampered the T cell egression from splenic reservoir, evaluated as CD3+ cell content, induced by AngII. In the end, we assessed the amount of T cells infiltration, finding that AngII-SDN mice were significantly protected in aorta (CD8+/mm2: veh-sham 197±17; veh-SDN 143±14; AngII-sham 293±36*; AngII-SDN 156±8) and kidney (CD8+/mm2: veh-sham 40±4; veh-SDN 34±4; AngII-sham 231±27*; AngII-SDN 29±5), *p<0.01 vs all other groups. Similar results were found for CD4+ infiltrates.

Our results demonstrate that the neuroimmune drive activated by chronic AngII infusion is mediated by the activation of the SSNA, converging into T cells activation in the spleen and their egression toward target organs, where they contribute to the onset of HTN.
Abstract 009: Vertical Sleeve Gastrectomy Reduces Mean Arterial Blood Pressure and Hypothalamic Endoplasmic Reticulum Stress Independent of Body Weight in Mice
Authors: McGavigan Anne K , Garibay Darline , Butler Scott D , Davisson Robin L , Cummings Bethany P
Published: March 2022

Bariatric surgery, such as vertical sleeve gastrectomy (VSG), results in remission of hypertension (HTN) and type 2 diabetes. The mechanism(s) by which this occurs remain elusive, but reduction in endoplasmic reticulum (ER) stress is a central concept. For example, VSG-induced reductions in ER stress in peripheral tissues contribute to improved insulin sensitivity. ER stress in the hypothalamus promotes development of HTN; however, brain ER stress has not been assessed in the context of bariatric surgery. Therefore, we hypothesized that VSG would ameliorate high fat diet (HFD)-induced HTN and this would be associated with reductions in hypothalamic ER stress. We have validated a mouse model of VSG that exhibits body weight-independent improvements in glucose homeostasis and peripheral ER stress. Here, male C57 mice (8 wks) were placed on a HFD (60%), which was maintained throughout the study. These mice underwent sham (n=4) or VSG (n=6) surgery and radiotelemeter implantation at 16 wks of age. Sham mice were food restricted to match their body weight to VSG mice (S-WM), to study the body weight-independent effects of VSG. At 2.5 months after surgery mice were fasted (6 hrs) and euthanized for tissue collection. Energy intake and body weight were reduced by ~25% after VSG compared with pre-operative values (39 ± 2 vs 30 ± 2g; P<0.01). Energy intake, body weight and adiposity did not differ between groups. Mean arterial pressure (MAP) was measured by telemetry at 2 and 6 wks after surgery. VSG mice exhibited lower MAP compared with S-WM (S-WM = 112.2 ± 1.4, VSG = 99.5 ± 2.3mmHg; P<0.01). Strikingly, the percent decrease in MAP from 2 to 6 wks after surgery was 4-fold greater in VSG compared with S-WM (%ΔMAP: S-WM = 9.3 ± 2.8, VSG = -5.2 ± 2.6; P<0.001). We assessed the PERK pathway of ER stress and inflammation in the hypothalamus by immunoblotting. Normalized PERKThr980 phosphorylation, downstream eIF2αSer51 phosphorylation and TNFα were reduced by 35%, 29% and 55% in VSG compared with S-WM, respectively (pPERK/PERK (AU): S-WM = 1.2 ± 0.2, VSG = 0.8 ± 0.1; peIF/eIF: S-WM = 1.2 ± 0.1, VSG = 0.8 ± 0.1; TNFα/tubulin: S-WM = 1.4 ± 0.3, VSG = 0.6 ± 0.1; P<0.05). Therefore, VSG produces body weight-independent reductions in MAP which may be due to VSG-induced reductions in hypothalamic ER stress.
Abstract 014: Nox1-derived ROS Impairs Internal Pudendal Artery Function via Nrf2 and Rho Kinase in Diabetic Mice
Authors: Lopes Rhéure A , Neves Karla B , Montezano Augusto C , Harvey Adam , Carneiro Fernando S , Touyz Rhian M , Tostes Rita C
Published: March 2022

Oxidative stress plays an important role in vascular dysfunction in diabetes, an important risk factor for erectile dysfunction (ED). Functional and structural changes in internal pudendal arteries (IPAs), which provide blood supply to the corpus cavernosum, can lead to ED. We hypothesized that downregulation of Nrf2-regulated enzymes, consequent to increased NOX1-derived ROS, impairs IPAs function in diabetic mice. IPAs and cultured vascular smooth muscle cells (VSMC) from C57BL/6 (control) and NOX1 knockout (KO) mice were used; diabetes (DM) was induced by streptozotocin in C57BL/6 mice. Vascular function assessment, by wire myography, demonstrated that IPAs from diabetic mice displayed increased contractility to phenylephrine (Phe, Emax: control 138.5±9.5 vs. DM 191.8±15.5) and decreased endothelial-dependent relaxation to acetylcholine (ACh, Emax: control 98.3±2.65 vs. DM 76.1±4.5). These responses were corrected by incubation of IPAs with tiron (ROS scavenger), bardoxolone (Nrf2 activator), ML171 (NOX1 inhibitor) and Y27632 (Rho Kinase inhibitor). IPAs from diabetic mice exhibited decreased Y276732-induced vasodilatation (LogEC50: control 5.8±0.1 vs. DM 5.3±0.1). Cultured VSMC from IPAs, maintained in high glucose (HG) medium, displayed increased levels of superoxide anion (59.6%±10.43) and nitrotyrosine (40.8%±9.8), as well as decreased NO production (37.7%±10.42) and nuclear accumulation of Nrf2 (20.42%±3.6), effects not observed in VSMC from IPAs isolated from NOX1 KO mice. The expression of Nrf2-regulated genes was also decreased in VSMC from IPAs maintained in HG [catalase (25.6%±0.05), HO-1 (21%±0.1) and NQO-1 (22%±0.1)], an effect prevented by the incubation with ML171. HG decreased H2O2 levels in control VSMC (29%±5.0), but increased H2O2 in NOX1 KO VSMC (45.8%±7.1), effects not observed when cells were pre-incubated with GKT 137831 (NOX1/4 inhibitor). In conclusion, diabetes-associated IPAs dysfunction involves increased NOX-1 derived ROS, decreased expression of Nrf2-regulated enzymes and activation of the Rho kinase pathway. These data suggest that Nrf2 may be vasoprotective in diabetes-associated ED. Financial Support: FAPESP, Brazil.
Abstract 019: Specific Knockdown of Renal Tubular Epithelial Ace Prevents Salt Sensitivity
Authors: Giani Jorge F , Fuchs Sebastien , Bernstein Ellen A , Bernstein Kenneth E , Gonzalez-Villalobos Romer A
Published: March 2022

We previously showed that mice lacking renal angiotensin-converting enzyme (ACE) do not accumulate angiotensin (Ang) II in the kidney and are protected against different forms of experimental hypertension, including salt sensitivity. However, these studies did not identify the locus of renal Ang II generation. Since ACE expression is high in the renal epithelium, we hypothesize that tubular epithelial ACE is the main source of renal Ang II and, is responsible for salt sensitivity. To study this, we designed an inducible tubular ACE knockdown mouse (it-ACE) that has three transgenes: one encoding the transcription factor tTA (Tet-off transactivator) that is under the control of the KSP-cadherin promoter only expressed in renal tubular cells. The second and third transgenes are activated by tTA and encode a short-hairpin RNAs (sh-RNA) degrading ACE mRNA in renal tubules. We found a lower basal ACE expression in the kidney of it-ACE compared to WT mice (19 ± 4 vs. 100 ± 26 AU; p<0.01 by Western blot). Selective tubular ACE suppression was confirmed by immunohistochemistry. At baseline, it-ACE mice display normal systolic blood pressure (SBP; 108 ± 4 mmHg), GFR (1288 ± 24 μl/min/100g b.w.) and urine concentration (2516 ± 184 mOsm/Kg after 12h water deprivation) compared to WT mice. To test the response of it-ACE mice to salt-sensitivity, we used a post L-NAME salt sensitivity protocol: L-NAME (0.5 mg/mL; 4 weeks), washout (1 week), high salt diet (HS, NaCl 4%, 3 weeks). In WT mice, L-NAME increased SBP from 109 ± 5 to 139 ± 4 mmHg (p<0.01; n=5). SBP then returned to baseline during the washout and increased again in response to the HS diet (135 ± 3 mmHg; p<0.01). Thus, WT mice, previously salt resistant, became salt sensitive. Remarkably, it-ACE mice, despite being as hypertensive as WT during the L-NAME phase, were still protected against salt sensitivity (110 ± 3 mmHg; p<0.01 vs. WT; n=6). Finally, we treated it-ACE mice with doxycycline (a tTA blocker) to restore tubular ACE specifically during the HS phase. Restoring tubular ACE in the mutant mice induced the development of salt sensitivity (134 ± 6 mmHg; p<0.01 vs. baseline; n=5). In conclusion, our data indicate that tubular epithelial ACE, and not ACE expression in endothelium or other locations, is essential for salt sensitivity.
Abstract 024: The Direct Renin Inhibitor Aliskiren Improves Vasodilation and Endothelial Function in Resistance Arteries from Diabetic and Hypertensive Patients
Authors: Savoia Carmine , De Ciuceis Carolina , Arrabito Emanuele , Paini Anna , Sada Lidia , Nicoletti Carmine , Carletti Raffaella , Rizzoni Damiano , Muiesan Maria Lorenza , Di Giioia Cira , Agabiti Rosei Enrico , Volpe Massimo
Published: March 2022

We previously demonstrated that the direct renin inhibitor aliskiren (ALK) significantly reduced the remodeling of subcutaneous resistance arteries of hypertensive patients as compared to the angiotensin-converting enzyme inhibitor ramipril (RAM). Here we questioned whether endothelial function of resistance arteries would improve after 1 year of blood pressure (BP) control with ALK or RAM.

Sixteen diabetic patients with mild essential hypertension were randomized to ALK (150-300 mg once daily, n=9) or RAM (5-10 mg once daily, n=7). Subcutaneous resistance arteries were dissected from gluteal biopsy and mounted on a pressurized micromyograph. Endothelium-dependent and -independent relaxations were assessed by concentration-response curves to acetylcholine (1 nM to 100 μM) and sodium nitroprusside (10 nM to 1 mM) respectively, in arteries pre-contracted with norepinephrine (10 μM). Carotid-femoral pulse wave velocity (PWV) was assessed by applantion tonometry. Forearm flow mediated dilation (FMD) was assessed by ultrasounds. The expression of P-eNOS/e-NOS and the markers of oxidative stress nitrotyrosine and LOX-1 were assessed by immunohistochemistry in resistance arteries.

Patients were similar for age, sex, BMI and glycemic and metabolic control. Systolic BP was significantly and equally reduced by both ALK and RAM (153±8.9 mmHg reduced to 128±7.3 mmHg and 151±10.6 mmHg reduced to 121±12.1, respectively, P<0.01) whereas diastolic BP was significantly reduced only in ALK-treated but not in RAM-treated patients (94.2±7.17 mmHg reduced to 81.4±6.31 mmHg, P<0.01; and 84.7±12.22 reduced to 78.6±7.48, NS, respectively). PWV and FMD were similar in both groups before and after treatment.

Endothelium-dependent vasodilation was improved only by ALK (max dilation 92.5±3.8% vs 50.5±14%, P<0.05) but not by RAM (max dilation 72.9±5.6% vs 61.8±14.5%, NS). Endothelium-independent vasodilation was similar in all the groups. Only ALK increased P-eNOS/eNOS expression (+44% vs before treatment, p<0.05). The markers of oxidative stress were similar in both groups before and after treatment.

In conclusion ALK improved endothelial function and induced vasodilation in resistance arteries from diabetic and hypertensive patients.
Abstract 025: Evidence for a Link between Gut Microbiota and Hypertension in the Dahl Rat Model
Authors: Mell Blair , Jala Venkatakrishna R. , Mathew Anna V , Byun Jaeman , Waghulde Harshal , Zhang Youjie , Haribabu Bodduluri , Vijay-Kumar Matam , Pennathur Subramaniam , Joe Bina
Published: March 2022

Gut microbiota play a critical role in maintaining physiological homeostasis. This study was designed to evaluate whether gut microbial composition impacts hypertension. 16S rRNA genes obtained from cecal samples of Dahl salt-sensitive (S) and Dahl salt-resistant (R) rats, were sequenced. Bacteria of the phylum Bacteriodetes were higher in the S rats compared with the R rats. Further, the family S24-7 of the phylum Bacteriodetes and the family Veillonellaceae of the phylum Firmicutes were higher in the S rats compared to the R rats. Analyses of the various phylogenetic groups of cecal microbiota revealed significant differences between S and R rats. Both strains were maintained on a high-salt diet, administered antibiotics for ablation of microbiota, transplanted with S or R rat cecal contents and monitored for blood pressure (BP). Systolic BP of the R rats remained unaltered irrespective of S or R rat cecal transplantation. Surprisingly, compared to the S rats given S rat cecal content, systolic BP of the S rats given a single bolus of cecal content from R rats was consistently and significantly elevated during the rest of their life and had a shorter lifespan. Lower level of fecal bacteria of the family Veillonellaceae and increased plasma acetate and heptanoate were features associated with the increased BP observed in the S rats given R rat microbiota compared with the S rats given S rat microbiota. These data demonstrate a link between microbial content and BP regulation and because the S and R rats differ in their genomic composition, provide the necessary basis to further examine the relationship between the host genome and microbiome in the context of BP regulation in the Dahl rats.
Abstract 026: Gut Bacteria Metabolite Attenuates Ang II-induced Cardiac Damage
Authors: Wilck Nicola , Bartolomaeus Hendrik , Balogh Andras , Marko Lajos , Dechend Ralf , Müller Dominik N.
Published: March 2022

Increasing evidence suggests that the gut microbiota critically influence host health and immune homeostasis. Microbiome-host communication occurs via gut bacterial metabolites which are resorbed by the host and target various organs. Short-chain fatty acids (SCFA) are produced from bacterial fermentation, are highly abundant in the gut but can also be detected in the blood. Recently, the SCFA propionate has been shown to regulate T cell differentiation into effector and regulatory T cells in peripheral tissues. Since activation of the immune system is known to substantially contribute to hypertensive target organ damage and anti-inflammatory strategies have been shown to be beneficial in animal models, we hypothesized that treatment with propionate would be beneficial in angiotensin (AngII)-induced target organ damage. Male NMRI mice received AngII infusions for two weeks and propionate (P) or vehicle (C) in drinking water. To deplete endogenous SCFA production mice were fed a low-fibre diet. Body weight was similar among all groups. Propionate treatment significantly reduced albuminuria (C 1143 ± 193; P 302 ± 69 μg/d). Propionate significantly reduced cardiac hypertrophy as measured by heart-to-tibia ratio (C 10.1 ± 0.4; P 8.9 ± 0.4 mg/mm) and was confirmed by echocardiography. Propionate treatment significantly reduced interstitial (C 16.5 ± 0.8%; P 6.6 ± 0.2%) and perivascular cardiac fibrosis (C 1.5 ± 0.06; P 1.1 ± 0.03 μm/μm) as measured by fibronectin and collagen I immunofluorescence, respectively. In vivo cardiac electrophysiology studies showed a significantly reduced susceptibility to ventricular arrhythmias in propionate-treated mice (C 71 ± 14%; P 24 ± 16%), indicating the functional relevance of the improved cardiac morphology. Propionate reduced the expression of IL-17 in CD4+ T cells in spleen and lymph nodes as measured by flow cytometry. Our data indicate that propionate attenuates AngII-induced cardiac remodeling and reduces susceptibility to arrhythmias. The gut microbiome is a promising target for treatment of hypertensive heart disease.
Abstract 027: Intestinal Permeability and Dysbiosis are Linked to Hypertension
Authors: Santisteban Monica M , Rubiano Andres , Stewart Daniel , Yang Tao , Cole-Jeffrey Colleen T , Zingler Michael B , Lobaton Gilberto O , Shenoy Vinayak , Zubcevic Jasenka , Simmons Chelsey S , Raizada Mohan K
Published: March 2022

Introduction:
Emerging evidence implicates the involvement of intestinal microbiota in overall physiological homeostasis. Altered microbial composition is associated with metabolic, cardiovascular, and neurological diseases. However, the role of intestinal microbiota in blood pressure control and hypertension (HTN) remains unexplored. The present study was designed to evaluate the hypothesis that both intestinal dysbiosis and altered intestinal function are critical pathophysiological events in HTN.

Methods:
16S ribosomal DNA from fecal samples from SHR and chronic angiotensin II (Ang II, 200ng/kg/min) rat models was utilized to compare gut microbial communities between normotensive and hypertensive animals. Gut permeability was assessed by accumulation of FITC-dextran (44mg/100g BW) in the plasma 4 hours following oral feeding. Ex vivo atomic force microscopy was used to determine small intestine and colon stiffness (a measure of permeability). Tight junction gene expression was quantified by qPCR.

Results:
We observed a significant decrease in microbial richness (20%), diversity (12%), and evenness (10%) in SHR vs WKY. This was associated with an increased Firmicutes (F)/Bacteroidetes (B) ratio (4±1 vs 24±5), a hallmark of gut dysbiosis. Additionally, we observed a 95% increase in plasma FITC-dextran in SHRs (1777±428 vs 3514±563 ng/ml, p<0.05), which correlated with decreased mRNA of several tight junction genes throughout the intestine, including
Ocln
,
Tjp1
, and
Cldn4
. In addition, we found increased stiffness of both small intestine and colonic tissue, as evidenced by increased elastic modulus in SHR (small intestine: 21.2±3 vs 53.7±8 kPa, colon: 15.7±2 vs 53.4±14 kPa, p<0.05). Similar decreased microbial richness and increased F/B ratio (~2 fold) were observed in the Ang II rat model at 4 weeks. Plasma FITC-dextran began to rise by day 14 (SBP=160 mmHg), and reached maximal increase of 65% by day 21 (SBP=185 mmHg). Furthermore, colon wall stiffness was significantly increased by day 21 of Ang II infusion.

Conclusions:
These observations show that increased gut permeability/leakiness and dysbiosis is associated with HTN. They are the first to demonstrate a profound intestinal pathophysiology and microbial dysbiosis in HTN.