bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P016: GYY4137, a Hydrogen Sulfide Donor, Mitigates Ang II-induced Extracellular Matrix Remodeling in Glomerular Endothelial and Mesangial Cells
Authors: Amin Matthew , Pushpakumar Sathnur , Kundu Sourav , Tyagi Geetansh , Tyagi Aaron , Sen Utpal
Published: July 2021

Hypertensive nephropathy is associated with progressive alteration of extracellular matrix (ECM) components. Both mesangial and glomerular endothelial cells have the ability to synthesize and degrade ECM proteins such as collagens by changes in the activity of matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). Endo180 is an extracellular fibronectin type II domain involved in lysosomal degradation of collagen which has been shown to mitigate renal fibrosis. More recently, hydrogen sulfide (H2S) has also been shown to mitigate hypertensive renal remodeling, however, its mechanism remains unclear. In this study, our aim was to investigate whether Angiotensin-II (Ang II) treatment alters the expression of Endo180, MMPs and TIMPs leading to dysregulation of collagen metabolism and whether GYY4137 (H2S donor) restores their levels to achieve homeostasis. Mesangial and mouse glomerular endothelial cells (MCs and MGECs respectively) were treated without or with Ang II (200 nM) and GYY4137 (250 μM) for 48hrs. Cell lysates were analyzed for MMP-13, -14, TIMP-1, Endo180, and collagen IV by Western blot, RT-PCR, and immunohistochemistry. In MGECs, Ang II treatment compared to its control decreased MMP-13/TIMP-1 ratio (0.75±0.44 vs. 2.48 ±0.73), and upregulated MMP-14/TIMP-1 ratio (0.64±2.10 vs. 0.96±1.47), and collagen IV (0.77±0.07 vs. 0.58±0.06). GYY4137 treatment mitigated these changes. In contrast, Ang II treatment in MCs decreased Endo180 compared to control (0.72±0.04 vs. 1.07±0.23), but did not alter the expression of MMP-13/TIMP-1, MMP-14/TIMP-1 ratios, and collagen IV level compared to control or MGECs. Similarly, immunostaining showed downregulation of MMP-13 and Endo180 in Ang II treated MGECs which was normalized following GYY4137 treatment. Endo180 was also normalized in MCs following GYY4137 treatment however, there was no change in MMP-14/TIMP-1 ratio or collagen IV level. We conclude that Ang II treatment causes adverse ECM remodeling in MGECs via downregulation of Endo180 and MMP-13 and upregulation of MMP-14 and TIMP-1 and in MCs by decreasing Endo180, and GYY4137 mitigates these changes in part, by modulating Endo180/MMP/TIMP pathway.
Abstract P058: Regional Sympathetic Activation Induced by Obstructive Apnea
Authors: Ferreira Caroline B , Cravo Sergio L , Stocker Sean D
Published: July 2021

Obstructive sleep apnea increases muscle sympathetic nerve activity (SNA) in humans that contributes to cardiovascular dysfunction including hypertension. The purpose of the present study was to determine if there are regional differences in apnea-induced sympathetic activation in rodents. Male Sprague Dawley rats (n: 8, 270-350 g) were anesthetized with urethane (1.2 g/kg i.v.) and prepared for recordings of renal, splanchnic, and lumbar SNA, phrenic nerve activity (PNA), mean arterial pressure (MAP) and heart rate (HR). Animals were exposed to 10 apneas performed by clamping a tracheal tube during 20 s each 2 min in room air. Changes in rectified and integrated (20 ms time constant) SNA were calculated by subtracting background noise after death. Basal MAP and HR were 89 ± 3 mmHg and 402 ± 14 bpm. Apneas in room air produced similar increases in SNA across various nerves (Δ renal: 96 ± 16%; Δ splanchnic: 109 ± 30%, and Δ lumbar: 93 ± 7%). These bursts increase in amplitude and the maximum response occurred in the end of 20 s of obstruction. Apnea also induced hypertension (Δ: 10 ± 2 mmHg), bradycardia (Δ: - 51 ± 25 bpm) and increased in PNA (Δ: 791 ± 194%). To test the contribution of chemoreceptors, obstructive apnea was repeated when animals were breathing 100% oxygen. Basal MAP and HR were 89 ± 3 mmHg and 402 ± 14 bpm. Hyperoxia reduced the sympathetic responses induced by apnea in renal, splanchnic and lumbar SNA (Δ renal: 40 ± 7%, Δ splanchnic: 68 ± 32%, and Δ lumbar: 52 ± 8%). The cardiovascular and respiratory response were also reduced (ΔMAP: 6±1; ΔHR: -22±8 and ΔPNA: 586 ± 149%). Therefore, obstructive apnea induces similar changes in SNA across various end-organs that depend in part of hypoxia stimulus.
Abstract P063: Pitavastatin Has Antihypertensive and Renoprotective Effects With Upregulation of No System and Down-regulation of Oxidative Stress in the Kidney of Spontaneously Hypertensive Rats
Authors: Hu Gaizun , Ito Osamu , Rong Rong , Xu Bin , Sakuyama Akihiro , Miura Takahiro , Ogawa Yoshiko , Ito Daisuke , Kohzuki Masahiro
Published: July 2021

Clinical trials have demonstrated renoprotective effects of atorvastatin (ATV) and pitavastatin (PTV), which belong to the strong statins, are more potent than other statins. We reported previously that ATV attenuated the development of hypertension in SHR with increasing the endothelial and neuronal NO synthases (eNOS, nNOS) expressions in the kidney, whereas ATV inhibited the eNOS phosphorylation at serin1177 (J Hypertes 28: 2278-2288, 2010). To clarify the mechanisms of renoprotective effects of PTV, the present study examined the effects of PTV on blood pressure, renal functions, NOS and oxidative stress in the kidney of SHR. Five-week-old, male SHR were given orally PTV (2mg/kg/day) or vehicle for 8 weeks. The systolic blood pressure (SBP) was measured. The NOS expression and eNOS phosphorylation were analyzed by Western blot. The NADPH oxidase activity was measured by the lucigenin-enhanced chemiluminescence method. PTV attenuated the progression of hypertension (220 ± 8 vs. 177± 4 mmHg, P<0.01) and albuminuria (684 ± 66 vs. 398 ± 42 mg/day, P<0.01) without changing plasma total cholesterol or creatinine. PTV increased the eNOS and nNOS expressions in the outer and inner medulla of the kidney (eNOS; by 182% and 186%, nNOS; by 315% and 194%, P<0.01). PTV significantly stimulated the eNOS phosphorylation at serin1177 in the inner medulla and inhibited the eNOS phosphorylation at threonine495 in the outer and inner medulla. PTV decreased hydrogen peroxide (13.4 ± 2.1 vs. 6.1 ± 1.2 nmol/day, P<0.05) and thiobarbituric acid reactive substances (TBARS) (236.6 ± 12.4 vs. 198.3 ± 10.6 nmol/day, P<0.05) in the urine and the NADPH oxidase activity (42681± 2515 vs. 32381 ± 1995 c.p.m/mg protein, P<0.01) in the renal cortex. These results indicate that PTV attenuates the development of hypertension and albuminuria in SHR with increasing the eNOS and nNOS expressions, changing the eNOS phosphorylation to an active form and mitigating oxidative stress in the kidney. The antihypertensive and renoprotective effects of PTV may be mediated in part by an upregulation of NO system and down-regulation of oxidative stress in the kidney.
Abstract P064: Case Report of Mals Surgery in Postural Orthostatic Tachycardia Syndrome
Authors: Ashangari Chandralekha , Suleman Amer
Published: July 2021

Background:
Postural Orthostatic Tachycardia Syndrome (POTS) is a form of dysautonomia associated with variety of symptoms like Headache, Abdominal discomfort, Dizziness/presyncope, Nausea, Fatigue, Lightheadedness, Sweating Sleep disorder, Tremor, Anxiety, Palpitations, Exercise intolerance. Median arcuate ligament syndrome (MALS, also known as celiac artery compression syndrome) is a condition characterized by abdominal pain, delayed gastric emptying, nausea, weight loss and other symptoms of autonomic dysfunction attributed to compression of the celiac artery and possibly the celiac ganglia by the median arcuate ligament. The researchers suggest that MALS should be considered in POTS patients who have persistent gastrointestinal symptoms.

The purpose of this research is to study the celiac artery velocity in POTS patients. That led us to think about an operative procedure that can reduce POTS symptoms through MALS surgery.

Patients and Method:
We present the case of a 17 year old male with POTS symptoms not improving with medical management and celiac artery ultrasound positive for MALS.His celiac artery velocities was higher in Inspiration as well as Expiration and MALS is confirmed with CT angiogram.He underwent laparoscopic MALS surgery where the Median arcuate ligament is flipped thereby decreasing the extrinsic compression on the celiac artery.

Results:
There appears to be tremendous improvement in the patient’s symptoms after the surgery for MALS.His nausea had almost disappeared.Before surgery he had vomiting twice a week, after surgery he had vomiting four times in three months. His lightheadedness had disappeared. Bluish discoloration of arms and feet when he used to stand had disappeared in the hospital after the procedure. Sensations of hands had improved. Heat intolerance had improved. His Sleep and constipation improved. There was no much improvement in fatigue. Autonomic tilt table test is repeated after surgery to see if there is definite objective change, Heart rate in the first 10 minutes of tilt test before the surgery was >120bpm,Heart rate after the surgery was <100 bpm.

Conclusions:
Laparoscopic MALS surgery was found to be extremely helpful in relieving POTS symptoms with immediate results.
Abstract P084: Oxidative Stress Preconditioning Is Required for Leptin to Stimulate Renin Release From Mouse Juxtaglomerular Cells
Authors: Mendez Mariela
Published: July 2021

Leptin is enhanced in animal models of obesity. The role of leptin in hypertension is unclear with some studies showing antihypertensive actions and others showing a pro-hypertensive role. In normotensive, non-obese, animals, infusion of leptin induces natriuresis. However, in animal models of enhanced oxidative stress, obesity, or activated renin-angiotensin system, infusion of leptin tends to increase blood pressure. Renin is a critical mediator of angiotensin-II formation, and thus blood pressure control. However, the direct effect of leptin on the release of renin from juxtaglomerular (JG) cells has not been studied. We hypothesize that under normal conditions leptin does not affect renin release whereas during high oxidative stress leptin stimulates renin release. We isolated primary cultures of mouse juxtaglomerular (JG) cells. After treatment with different agonists, renin released to the supernatant was measured by radioimmunoassay. We first tested the direct effect of murine leptin on renin release. We found that 1 hr treatment with leptin (0.1-1 uM) decreased basal renin by 20 ± 5% (p<0.05; n=8). Treatment of JG cells for longer periods (4 and 24 hrs) did not affect renin release (n=6) or total renin expression (n=4). We then tested whether oxidative stress modified the effect of leptin on renin release. For this we pre-incubated JG cells with 10 uM hydrogen peroxide (H2O2) for 1 hr. After this, the medium was removed and H2O2 was completely washed out from JG cells followed by treatment with vehicle (cont) or 10 uM leptin. We found that, in cells pre-treated with H2O2, leptin increased renin release by 49.2 ±16 %(P<0.05 vs vehicle). By Western blot, we detected the expression of the leptin receptor in lysates from JG cells. We concluded that under normal conditions leptin inhibits renin release from JG cells. However, after exposure to H2O2, leptin stimulates renin release. Our data suggest the hypothesis that oxidative stress reverses the inhibitory effect of leptin on renin release and supports a pro-hypertensive role for leptin during chronic inflammatory conditions that induces oxidative stress.
Abstract P089: Inhibition of AT1-AAs by Direct Binding Reduces Blood Pressure and Natural Killer Cell Activation in Response to Placental Ischemia of Pregnancy; Emphasizing the Importance of Novel Drug Development in the Treatment of Preeclampsia
Authors: Campbell Nathan , Cunningham Mark W , Cornelius Denise C , LaMarca Babbette
Published: July 2021

Preeclampsia (PE), hypertension with proteinuria during pregnancy, is associated with activating antibodies to the angiotensin II receptor (AT1-AA) and activation of cytolytic natural killer (NK) cells. The objective of our study was to determine if AT1-AA inhibition inhibits cytolytic NK cell activation in the reduced uterine perfusion pressure (RUPP) rat model of PE. We utilized a novel approach of specific epitope binding to inhibit AT1-AAs: AT1-AA inhibitory peptide (2ug/ml saline) was infused via miniosmotic pumps into RUPP rats beginning on day 14 of gestation. On day 19 of gestation, blood pressure (MAP) was measured and flow cytometry was performed to measure total and cytolytic NK cells in renal and placental tissues from all groups of rats.

MAP significantly increased from 87.1±6.2 in NP (n=5) to 125±2.3 in RUPP (n=6). Inhibition of AT1-AA by direct binding attenuated the hypertensive response to 74.9±19.02 mmHg in RUPP + AT1-AA inhibitor (n=3). Total renal NK cells measured at 10.21±3.69% in NP, 24.19±6.63% in RUPP, and 14.25±7.52% in RUPP + AT1-AA inhibitor. Total placental NK cells were 6.87±2.84% in NP (n=6), 27.62±10.97% in RUPP (N=6), and 6.35±3.90% in RUPP + AT1-AA inhibitor (N=5) rats. Importantly, activated cytolytic placental NK cells were significantly increased in NP (0.44±.24%) compared to RUPP (11.87±2.06%), and was blunted after epitope binding of AT1-AA in RUPP + AT1-AA inhibitor (2.33±1.02%, p<.0001 vs RUPP).

These studies indicate that AT1-AA inhibition improves maternal blood pressure and attenuates cytolytic activation of NK cells in response to placental ischemia, thereby emphasizing the importance of drug discovery for AT1-AA inhibition to improve pregnancy outcomes in preeclamptic patients.
Abstract P109: Angiotensin-(1-9) Reverses Cardiac Dysfunction in a Model of Angiotensin II-Induced Hypertensive Heart Disease by Acting as a Positive Inotrope
Authors: Nather Katrin , Flores-Muñoz Mónica , Wills Lauren , Touyz Rhian M , Loughrey Christopher M , Nicklin Stuart A
Published: July 2021

Angiotensin II (AngII) is involved in the pathophysiology of cardiovascular diseases (CVD) such as hypertension and heart failure. The counter-regulatory axis of the renin angiotensin system is centred on ACE 2 generating angiotensin-(1-7) [Ang-(1-7)] opposing the pathological actions of AngII in the heart. We recently showed that angiotensin-(1-9) [Ang-(1-9)] is part of this axis potentially acting
via
the angiotensin type 2 receptor to inhibit AngII-induced cardiomyocyte hypertrophy
in vitro
and cardiac remodelling in the SHRSP rat. Here, we assessed whether Ang-(1-9) can reverse chronic AngII-induced cardiac pathology.

C57BL/6J mice were infused with H
2
O (control) or 48μg/kg/hr AngII for 2 weeks to induce cardiac contractile dysfunction as measured by a reduction in fractional shortening (FS) [control 54.8±3.0%; AngII 35.3±1.9%; p<0.05]. Minipumps were replaced and mice received either H
2
O, AngII or AngII with Ang-(1-9) (48μg/kg/hr) for a further 2 weeks. Mice receiving Ang-(1-9) in addition to AngII showed a recovery in FS [control 50.5±2.2%; AngII 33.6±1.9%; AngII+Ang-(1-9) 44.0±3.5%; p<0.05]. However, Ang-(1-9) did not affect AngII-induced cardiac hypertrophy [heart weight/tibia length (mg/mm): control 10.6±0.4; AngII 11.6±0.4; AngII+Ang-(1-9) 13.32±0.9], cardiomyocyte size [control 23.2±0.9μm; AngII 26.1±1.0μm; AngII+Ang-(1-9) 28.3±1.2μm] or myocardial fractions of collagen I [control 2.3±0.4%; AngII 6.5±0.9%; AngII+Ang-(1-9) 5.0±0.5%] and collagen III [control 2.0±0.3%; AngII 4.1±0.7%; AngII+Ang-(1-9) 3.0±1.3%]. To determine if Ang-(1-9) directly alters cardiac contractility, isolated rat hearts were Langendorff perfused at a constant heart rate (320 bpm) and intra-ventricular pressure was measured. Perfusion with 1μm Ang-(1-9) for 10min induced a significant and sustained increase in developed pressure [max. response: 105.8% normalised to control; p<0.05]. In contrast, perfusion with 1μm AngII only led to a small transient increase in developed pressure whereas Ang-(1-7) had no effect.

These results demonstrate for the first time that Ang-(1-9) reverses chronic AngII-induced cardiac dysfunction and acts directly as a positive inotrope suggesting therapeutic potential in various CVDs.
Abstract P110: Mrgd Expression in Cardiovascular Related Areas
Authors: Oliveira Aline C , Peluso Augusto A , Qadri Fatimunnisa , Alenina Natalia , Bader Michael , Santos Robson
Published: July 2021

Recently a new peptide was discovered as part of the Renin Angiotensin System, the heptapeptide alamandine. This new component is a product of the catalytic hydrolysis of Angiotensin A or can also be formed from decarboxilation of Angiotensin-(1-7). Interestingly, alamandine effects were independent of Angiotensin-(1-7) receptor Mas and the Mas-related G protein receptor member D (MrgD) was described as an alamandine receptor. Previous studies have reported that MrgD is expressed predominantly in small diameter IB4(+) neurons in the dorsal root ganglion (DRG). However, functional experiments performed in our lab showed that alamandine has antihypertensive and cardioprotective effects, indicating that MrgD might be also expressed in another tissues. Objective: Identify the anatomical localization of MrgD receptors in blood vessels, heart and in cardiovascular- related centers of the mouse brain. Materials and Methods: Mice were euthanized and then perfused. Brain, Aorta and heart were removed and postfixed. Serial sections were made in a cryostat, hydrated with PBS and permeabilized with 0.2% Tween 20, blocked with 5% of BSA, followed by a rabbit anti-MrgD and an Alexa 488-labeled anti-rabbit antibodies. Immunostaining specificity was characterized by performing experiments using MrgD receptor knockout mice as control. Results: Differently than described before, MrgD expression is not restricted to neurons at DRG. Immunofluorescence for MrgD receptor was detected throughout the trigeminal tract, Cerebellum, Cortex, Insular Cortex, Hypothalamus and in some nuclei of the brainstem. In addition, corroborating previous functional studies from our laboratory showing that Alamandine has an endothelium-dependent vasorelaxant effect we also observed positive fluorescence in aorta endothelial and smooth muscle cells Moreover, MrgD-positive immunofluorescence was also detected in cardiomyocytes, in the membrane and particularly in the nuclear and perinuclear area expanding the evidence that alamandine-induced effects are mediated by MrgD receptor. These observations are in keeping with previous functional studies and unmasked new targets for exploring the biological relevance of alamandine/MrgD.
Abstract P113: Angiotensin Converting Enzyme 2 Modulates Bradykinin B1 Receptor Function During DOCA-Salt Hypertension
Authors: Sriramula Srinivas , Lazartigues Eric
Published: July 2021

DOCA-salt hypertension is associated with reduced angiotensin converting enzyme 2 (ACE2) and increased bradykinin B1 receptor (B1R) expression in the brain. ACE2 hydrolyzes des-Arg(9)-bradykinin, the endogenous B1R agonist, into inactive metabolites. Therefore, we hypothesized that ACE2 overexpression or deletion modulates B1R function in the brain during neurogenic hypertension. To test this hypothesis, we used mice overexpressing ACE2 in neurons (SA), ACE2 knockout and B1R knockout mice. Blood pressure (BP) was monitored using telemetry probes in conscious animals. While baseline BP was not different between strains, DOCA-salt treatment (1 mg/g body weight DOCA, 1% NaCl for 3 weeks) resulted in a significantly lower BP in B1R knockout mice (121 ±2 mmHg, n=5) compared to wildtype (WT) mice (138 ±3 mmHg, n=8). DOCA-salt hypertension resulted in 27% decrease (74 ±6 vs. 54 ±2 Fluorescence Units (FU)/min/μg of protein, p<0.05) in ACE2 activity in the hypothalamus, but not in B1R knockout mice with DOCA (69 ±6 vs. 65 ±3 FU/min/μg of protein). In DOCA-treated WT mice, B1R mRNA (Real time PCR) and protein expression (Western blot) in the hypothalamus were increased by 3 and 2 fold (n=6, p<0.01), respectively. This increased B1R expression was blunted in SA mice with DOCA (3.2 ±0.4 vs. 0.9 ±0.1 fold, p<0.001) but not in ACE2 knockout mice with DOCA (3.2 ±0.4 vs. 3.1 ±0.9 fold). Moreover, DOCA-salt treatment resulted in an increased expression of pro-inflammatory ADAM17 in the brain by 2.2 fold (n=6, p<0.01 vs. WT). ACE2 overexpression or B1R knockdown blunted this ADAM17 expression (1.4 ±0.1 and 1.1 ±0.6 fold, respectively, n=3, p<0.01 vs. WT+DOCA), while it was remain increased in ACE2 knockout mice (2.6 ±0.7 fold, n=3, p<0.01) compared to control mice. Together, our data provide novel evidence to support a role for ACE2 in the modulation of central B1R function in the development of DOCA-salt hypertension.
Abstract P116: Effects of Febuxostat on Blood Pressure and Renal Functions in Dahl Salt-Sensitive Rats
Authors: Sakuyama Akihiro , Ito Osamu , Ogawa Yoshiko , Komatsu Miwa , Hu Gaizun , Miura Takahiro , Muroya Yoshikazu , Suda Chihiro , Kohzuki Masahiro
Published: July 2021

Several clinical and basic studies have reported that febuxostat (Fx), xanthine oxidase (XO) inhibitor, has anti-hypertensive and renal protective effects. However, these effects of Fx are controversial, and the mechanisms have not been clarified. In this study, we investigated the effects of Fx on blood pressure and renal functions in Dahl salt-sensitive rats. Eight-week-old, male Dahl salt-sensitive rats were divided into three groups: 1) normal salt diet (NS) group; 2) high salt diet (HS) group; 3) HS + Fx group. The NS or HS groups were fed diet containing 0.6% or 8% NaCl, and the Fx group treated with Fx (3 mg/kg/day in drinking water). After 8 weeks, the systolic blood pressure (SBP), renal functions, and renal histology were examined. HS significantly increased the SBP, urinary protein excretion, and plasma creatinine and uric acid (p<0.01), and exacerbated glomerular sclerosis. HS also significantly increased urinary H2O2 and XO activity in the renal cortex (3.27±0.37 vs. 0.78±0.16 mU/mg protein) and outer medulla (1.84±0.15 vs. 0.76±0.04 mU/mg protein) (p<0.01). The Fx treatment significantly ameliorated the HS-increased SBP (174±6 vs. 209±4 mmHg), urinary protein excretion (152±21 vs. 325±40 mg/day), plasma creatinine (0.29±0.01 vs. 0.41±0.03 mg/dl), uric acid (0.53±0.06 vs. 1.67±0.21 mg/dl) (p<0.01) and glomerular sclerosis. The Fx treatment significantly suppressed the HS-increased urinary H2O2 (339.6±27.8 vs. 483.8±47.4 nM/day, p<0.01), and almost completely inhibited XO activity in the renal cortex and outer medulla. In additional study, we investigated the effects of Fx on blood pressure and renal functions in spontaneously hypertensive rats. The Fx treatment (3 mg/kg/day in drinking water) for 8 weeks did not significantly change the SBP (189±6 vs. 205±4 mmHg), plasma creatinine (0.19±0.01 vs. 0.18±0.01 mg/dl), or urinary albumin excretion (214±20 vs. 206±33 μg/day). These results indicate that anti-hypertensive and renal protective effects of Fx in Dahl salt-sensitive rats fed high-salt diet, suggesting that Fx has anti-hypertensive and renal protective effects in salt-sensitive hypertension.
Abstract P122: Mitochondrial Transcription Factor 2B Regulates Endothelial Cell Morphology
Authors: Forrester Steven J , Kawai Tatsuo , Elliot Katherine J , Eguchi Kunie , Park Joon Y , Rizzo Victor , Eguchi Satoru
Published: July 2021

Mitochondrial dysfunction, such as observed in endothelial cells, has been implicated in various cardiovascular diseases including, hypertension and atherosclerosis. Mitochondrial transcription factor 2B (TFB2M) is an essential component to maintain proper transcriptional and functional control of mitochondrial DNA. As well, elongation of endothelial cells is a characteristic of atheroprotective regions within the vasculature, and the relationship between the mitochondria and EC shape is currently unknown. The aim of our study is to investigate the hypothesis that TFB2M has a novel role in enhancing endothelial function. Human umbilical vein endothelial cells (HUVECs) were harvested 72 hours after adenoviral transduction with TFB2M (100 moi). HUVECs transduced with TFB2M showed an elongated cell morphology when compared to GFP control. To further investigate the effect of TFB2M on regulating mitochondrial function and cell shape, immunoblotting was carried out for markers involved in mitochondrial function/dynamics and markers indicative of cytoskeleton reorganization. TFB2M transduction resulted in increased expression of mitochondrial biogenesis marker VDAC (2.6 fold increase), mitochondrial fusion protein MFN2 (2.1 fold increase), and phosphorylated myosin phosphatase targeting protein MYPT1 at Thr850 (2.2 fold increase,
p
< 0.05 for all proteins). Additionally, fluorescence microscopy showed enhanced mitochondrial fluorescence in TFB2M transduced cells using mitotracker red staining (3.5 fold increase,
p <
0.001). These data indicate that TFB2M has a previously undiscovered function contributing to altered EC function and shape, potentially through a novel mitochondrial retrograde signaling mechanism. Further research will focus on distinguishing the exact mechanisms culminating in a protective EC phenotype and the beneficial role of endothelial TFB2M-mediated enhanced mitochondrial function in the treatment of EC dysfunction associated with various cardiovascular diseases.
Abstract P124: Human Small Artery MicroRNA Expression Profiles: Changes in Type 2 Diabetes and Associations with Endothelial Function
Authors: Jensen David M , Widlansky Michael E , Chu Chen , Liu Pengyuan , Liu Yong , Kriegel Alison , Wang Jingli , Malik Mobin , Ying Rong , Couillard Allison , Liang Mingyu
Published: July 2021

Background:
Studies of experimental models and human blood samples support an important role of microRNAs (miRNAs) in the development of vascular dysfunction in hypertension and diabetes mellitus (DM). Information on miRNA expression in clinically directly relevant tissues such as human small arteries and its relationship with impaired vascular endothelial function is currently lacking.

Methods and Results:
38 subjects (18 type 2 DM, 20 controls) underwent gluteal adipose pad biopsy to obtain small arteries for miRNA expression profiling by small RNA deep sequencing. In vivo conduit artery endothelial function was measured by brachial artery reactivity. In vitro microvascular endothelium dependent vasodilation was measured by videomicroscopy. Correlations between miRNA expression and measurements of endothelial function were calculated using generalized linear models. Several miRNAs correlated with measurements of vascular structure and function. Endothelium dependent vasodilation was impaired in type 2 DM subjects compared to controls based on both the vasodilatory response to peak dose acetylcholine (44±25 vs. 69±18 %, P=0.04) and by analyses of the entire acetylcholine dose-response curve. Several miRNAs were differentially expressed in small arteries from type 2 DM subjects, two of which were verified by real-time PCR. Cross-referencing the top 30 miRNAs (P<0.015) with prior studies of plasma miRNA expression in DM subjects identified 7 miRNAs differentially expressed in both human small arteries and plasma, all of which have some reported role in vascular regulation.

Conclusions:
Multiple miRNAs are differentially expressed in human small arteries in DM patients and correlated with in vivo or in vitro measurements of endothelial function, suggesting an important role of microvascular miRNAs in the development of endothelial dysfunction in humans.
Abstract P181: Circulating Second-messenger Glycerophosphocholines and Cardiovascular Risk Factors in a Population-based Sample of Adolescents
Authors: Czajkowski Simon , Abrahamowicz Michal , Leonard Gabriel , Perron Michel , Richer Louis , Veillette Suzanne , Gaudet Daniel , Wang Yun , Xu Hongbin , Taylor Graeme , Paus Tomas , Bennett Steffany , Pausova Zdenka
Published: July 2021

Circulating second-messenger glycerophosphocholines (smGPCs), including lysophosphatidylcholines and platelet-activating factors, are low-abundance plasma phospholipids that modulate atherosclerosis and inflammation and, in turn, the risk for cardiovascular disease (CVD). Although CVD is a slow-progressing disease culminating in middle-to-late adulthood, its initial stages may be seen already in adolescence. Here, we investigated whether circulating smGPCs are associated with classical CVD risk factors - excess body fat, elevated BP, insulin resistance and low-grade inflammation - during adolescence. We studied a population-based sample of 1029 adolescents (52% females, 12-18 years), as part of the Saguenay Youth Study. We used targeted serum lipidomics (LC-ESI-MS) to identify and quantify circulating smGPCs within the 440-640 Da range. In all participants, we also measured: (i) visceral fat with MRI and total body fat with bioimpedance; (ii) blood pressure (BP) beat-by-beat for five minutes under standard clinical conditions; and (iii and iv) fasting serum insulin (as an index of insulin resistance) and CRP (as an index of low-grade inflammation). We identified a total of 81 smGPCs that varied by the length and saturation of their fatty acyl residues and the type of linkage these residues are attached to the glycerol backbone. Over 30 of them were associated with multiple CVD risk factors (p<6x10
-4
). Most of these associations were inverse and involved ‘medium’ mass smGPCs. Positive associations were also seen and these involved ‘low’ or ‘high’ mass smGPCs. Most strongly
inversely
associated smGPCs were: (i) PC(20:6/0:0) and PC(O-18:6/2:0), which were associated with total body fat (p<3x10
-14
) and CRP (p<8x10
-36
); and (ii) PC(16:0/2:0), which was associated with visceral fat (p=2x10
-18
) and BP (p<1x10
-5
). The most strongly
positively
associated smGPC was PC(14:1/0:0), which was associated with visceral fat (p=8x10
-8
) and fasting insulin (p=2x10
-24
). Thus, specific circulating smGPCs are strongly associated with multiple CVD risk factors in adolescence; some of these associations may be ‘protective’ whereas others ‘adverse’. Circulating smGPCs may serve as novel biomarkers of early risk for CVD.
Abstract P182: Advanced Atherosclerosis is Associated with Systemic and End-organ Inflammation, Vascular Oxidative Stress and Endothelial Dysfunction but not Hypertension in Mice
Authors: Dinh Quynh N , Drummond Grant R , Diep Henry , Chan Christopher T , Ferens Dorota , Sobey Christopher G , Chrissobolis Sophocles
Published: July 2021

Introduction:
Evidence suggests that hypertension involves underlying inflammation, however whether atherosclerosis - a chronic inflammatory condition - can cause hypertension is unknown. We tested whether blood pressure (BP) is higher in high-fat fed ApoE-/- vs chow-fed wild-type (WT) mice, and whether advanced atherosclerosis is associated with systemic and end-organ inflammation, oxidative stress and endothelial dysfunction.

Methods:
Male ApoE-/- and WT mice were placed on high fat and chow diets, respectively, from 5-56 weeks. To clarify the effects of ageing alone, aged WT mice were compared to young chow-fed WT mice (8-12 week old). We measured systolic BP, plasma cytokine levels, mRNA expression of inflammatory markers, vascular superoxide and endothelial function.

Results:
There was no difference in BP of aged ApoE-/- (104.2 ± 2.9 mmHg) and age-matched WT mice (113.2 ± 1.3 mmHg) (n=13-18, P>0.05). However, plasma IL-6, TNF-α and IFN-γ were elevated in ApoE-/- by more than 2-fold vs age-matched WT (n=9-10, all P<0.05), as was brain expression of IL-1β, IL-6, TNF-α, IFN-γ, TGFβ1, CCR2, CCL2, CCL7, CCL8, CCL12 and IL-10 (n=9-10, all P<0.05), and aortic expression of IL-6, CCR2, CCL8 and CCL12 (n=6-8, all P<0.05). Ageing, but not atherosclerosis, increased renal expression of IL-1β, IL-6, TNF-α, CCR2, CCL2, CCL7, CCL8, CCL12 and Foxp3, and aortic expression of CCL2, IL-10 and Foxp3 by at least 2-fold (n=6-10, all P<0.05). In ApoE-/- aorta, Nox2-dependent superoxide production was 4-fold greater than in WT (n=5-6, P<0.05), and endothelium-dependent vasorelaxation to carbachol was markedly reduced by more than half (n=5-7, P<0.05). Ageing alone had no effect on BP, systemic inflammation or endothelial function.

Conclusions:
Despite the systemic and end-organ inflammation, oxidative stress and endothelial dysfunction, advanced atherosclerosis does not result in elevated BP.
Abstract P184: Effects of Vagus Nerve Stimulation on Hemodynamics and Inflammation in a Rheumatoid Arthritis Model in Rats
Authors: Salgado Helio C , Dias Daniel P , Bassi Gabriel S , Kanashiro Alexandre , Cunha Thiago M
Published: July 2021

The electrical stimulation of neural pathways has been considered a reliable alternative for treating some pathophysiological conditions, for instance, rheumatoid arthritis. Recently, the concept of electroceuticals has emerged and suggests that proper anatomic mapping associated with identification of electrical stimulation patterns for each neural pathway would tailor this tool. The effects of electrical stimulation of the vagus nerve (VNS) on hemodynamics and inflammatory responses were assessed in a rheumatoid arthritis experimental model. Male Wistar rats (280 g body mass) were anesthetized (ketamine: 57 mg/kg; xylazine: 10 mg/kg) and instrumented with a polyethylene catheter into the femoral artery combined with a stainless steel bipolar electrode around the left vagus nerve. Animals were kept anesthetized and had the pulsatile arterial pressure recorded at baseline during 10 minutes, followed by a single session (2-minutes long) of VNS under three different conditions: A) 5 Hz, 0.1 ms, 1 V; B) 10 Hz, 0.1 ms, 1 V; and, C) 20 Hz; 0.1 ms; 3 V. Immediately after VNS ceased, rats were injected with zymosan (100 μg/50 μL) into the femorotibial joint to elicit rheumatoid arthritis. Rats were allowed to rest over the next six hours and afterwards were killed and had the synovial fluid collected for neutrophil count. Control rats were subjected to similar procedures but without VNS. The VNS condition A and B elicited a transitory bradycardia (A: 23±3, B: 23±2 Δbpm; as compared to baseline). No changes in blood pressure were seen following VNS at conditions A and B. VNS under C condition elicited pronounced transient bradycardia (101±13 Δbpm; as compared to baseline) and produced a transient hypotensive response (26±6 ΔmmHg, as compared to baseline). VNS at conditions A and B had anti-inflammatory effect showed by neutrophil count (A: -44±8, B: -38±7; percentage change as compared to control rats). However, VNS at C condition had no anti-inflammatory effect. Therefore, VNS was an effective anti-inflammatory tool that did not elicit remarkable hemodynamic alterations.
Abstract P234: High Sodium Intake is Associated with Increased Hemoglobin A1C in Young Overweight/Obese African Americans
Authors: Parikh Samip J , Bhagatwala Jigar , Raed Anas , Huang Ying , Kotak Ishita , Harshfield Gregory A , Dong Yanbin , Zhu Haidong
Published: July 2021

Introduction:
Whether high sodium intake, assessed by 24-hour urinary sodium excretion (24hrUNaEx), is associated with altered glycemic control, evaluated by hemoglobin A1C (HbA1C), in the African American population remains unknown. We aimed to evaluate the relationship between 24hrUNaEx and HbA1C in young overweight/obese African Americans.

Methods:
A total of 106 apparently healthy overweight/obese drug-naïve African Americans were recruited. Subjects were asked to discard the first morning urine specimen and collect all remaining urine specimens for next 24-hr including a urine specimen of the following morning. HbA1C was measured from venous blood by ion-exchange chromatography.

Results:
The means (± SE) of age and body mass index (BMI) of subjects (67%, 71/106 females) were 24.30±0.82 years and 35.51±0.70 kg/m2, respectively. Average 24hrUNaEx was 172.17±7.09 mEq/L/d, which corresponded to average sodium intake of 3.96±1.63 g/d. Pearson’s correlation analysis revealed a positive correlation between log transformed 24hrUNaEx and HbA1C after adjusting for age, sex, BMI, and systolic blood pressure (r=0.20, p=0.04). In a subgroup analysis involving subjects with HbA1C ≥5.7% (N=40), the correlation between 24hrUNaEx and HbA1C was stronger even with adjustment for the above variables (r=0.35, p=0.04).

Conclusions:
High sodium intake is associated with increased HbA1C independent of traditional risk factors in our study population. This relationship was stronger in subjects with HbA1C ≥5.7%, which by definition represents prediabetes (HbA1C ≥5.7 & <6.5%) and diabetes (HbA1C ≥6.5%). Although not fully understood, the possible mechanism by which high sodium intake could contribute to glycemic dysregulation involves cellular dysfunction and apoptosis of pancreatic beta cell induced by high sodium intakes via inflammation and oxidative stress.
Abstract P235: Employing the DASH Diet to Treat Non-dippers: A Two-month Intervention Study
Authors: Pandey Arjun K
Published: July 2021

Introduction:
Hypertensive patients with abnormal circadian blood pressure patterns, including a lack of nocturnal blood pressure dipping or rises in blood pressure from daytime to night-time, are at an increased risk for numerous cardiovascular events including strokes, heart failure and renal failure. Currently, limited therapeutic strategies exist to treat non-dippers. In this study, we examine the role of obesity on circadian blood pressure patterns and the impact of lifestyle intervention on nocturnal dip.

Methodology:
24-hour ambulatory blood pressure monitoring was performed before and after a 2-month intervention employing the DASH diet and lifestyle program with a targeted 5% weight loss in 80 volunteers. 20 control patients had a healthy nocturnal dip, 30 patients had a non-dipping blood pressure pattern, and 30 patients had a rise in blood pressure nocturnally from daytime.

Results:
At baseline, there was a linear correlation between individuals' BMI and nocturnal blood pressure aberrancies (r= 0.60, p<0.0001). The control group had the lowest average BMI of 28.1 kg/m2. Non-dippers had a slightly higher average BMI of 30.3 kg/m2, and those with a rise in blood pressure nocturnally had the greatest average BMI of 35.3 kg/m2.

After the two-month lifestyle intervention, individuals who achieved weight loss had significantly greater average reductions in nocturnal blood pressure (24.3 mm Hg), compared to daytime (12.1 mm Hg), resulting in the restoration of a more normal nocturnal dip and circadian blood pressure pattern. Non-dippers who achieved a 5% reduction in weight during the intervention had an average 8.31% nocturnal dip by the end of the study. Individuals who lost less than 5% of their weight or who gained weight continued to have a non-dipping blood pressure pattern by the end of the study.

Conclusions:
The results of this study would suggest that perhaps reducing weight by adhering to the DASH diet and lifestyle intervention could be examined as therapeutic avenues for non-dippers in the future. The long-term effects of a restoration of normal circadian blood pressure pattern warrants further investigation.
Abstract P241: Uric Acid-Induced Adipocyte Dysfunction is Attenuated by HO-1 Upregulation: Potential Role of Antioxidant Therapy to Target Obesity
Authors: Puri Nitin , Sodhi Komal , Getty Morghan , Khitan Zeid
Published: July 2021

Increased uric acid levels have been implicated in the pathogenesis of metabolic syndrome. To examine the mechanisms by which this occurs we hypothesized that an increase in Heme Oxygenase-1, a potent anti-oxidant gene will decrease uric acid levels and adipocyte dysfunction via suppression of ROS and xanthine oxidase levels. We examined the effect of uric acid, on adipogenesis in human mesenchymal stem cells (MSCs) in the presence and absence of cobalt protoporphyrin (CoPP), HO-1 inducer and tin mesoporphyrin (SnMP), HO activity inhibitor. Uric acid increased adipogenesis by increasing NADPH oxidase expression and elevation in the adipogenesis markers C/EBPα, PPARγ, Mest while decreasing small lipid droplets and the expression of Wnt10b. Importantly, we treated MSCs with fructose, a fuel source that increase uric acid levels. Our results showed that fructose increased XO expression as compared to the control and concomitant treatment with CoPP significantly decreased XO expression and also decreased uric acid levels. These beneficial effects of CoPP were reversed by SnMP; supporting a role for HO activity in mediating these effects. These novel findings demonstrate that increased levels of HO-1 appear crucial in modulating the phenotype of adipocytes exposed to uric acid and in down regulating XO and NADPH oxidase levels. Furthermore, this study offers new insight into potential therapies by which targeting the production and/or downstream signaling of uric acid can curtail adipogenesis.
Abstract P600: Conditional Knockout of AT1a Receptors Selectively in The Proximal Tubules Attenuates Renal Ischemia-Reperfusion Injury in Mice.
Authors: Zhang Jianfeng , Li Xiao C , Chen Fang , Soleimani Manoocher , Zhuo Jia L
Published: July 2021

The activation of the intrarenal renin-angiotensin system plays an important role in the pathogenesis of renal ischemia-reperfusion injury, but the underlying cellular and signaling mechanisms remain incompletely understood. In the present study, we tested the hypothesis that conditional knockout of AT1a receptors selectively in the proximal tubules attenuates renal ischemia-reperfusion injury in mice. Three groups (n=5-8/per group) of adult male C57BL/6J (WT), global AT1a receptor-deficient (AT1a-KO), and conditional proximal tubule-specific AT1a-KO mice (PT-AT1a-KO) were subjected to sham surgery or 30 min unilateral left kidney ischemia, followed by reperfusion for 24 h or 7 days, respectively. Under basal conditions, systolic blood pressure was 25 ± 3 mmHg lower in global AT1a-KO (p<0.01) or 13 ± 3 mmHg lower in PT-AT1a-KO mice (p<0.05), respectively. Systolic blood pressure, 24 h urine and urinary sodium excretion were not significantly altered in all strains 24 h or 7 days after renal ischemia-reperfusion. Kidney wt. to body wt. ratio, but not heart wt. to body wt. ratio, was significantly increased in both AT1a-KO and PT-AT1a-KO mice (p<0.05). Renal ischemia-reperfusion injury was assessed by Masson Trichrome staining and compared between WT, AT1a-KO and PT-AT1a-KO mice. No significant glomerular, tubulointerstital, and peri-vascular fibrotic responses were observed in sham controls of all strains. However, significant fibrotic responses were observed in the glomeruli, cortical tubulointerstitial and peri-vascular tissues in WT mice 24 h or 7 days after renal ischemia-reperfusion (p<0.01). Surprisingly, however, glomerular, tubulointerstital, and peri-vascular fibrotic responses were significantly worsen, rather than improved, in global AT1a-KO mice (p<0.01). By comparison, conditional deletion of AT1a receptors selectively in the proximal tubules markedly attenuated glomerular, tubulointerstital, and peri-vascular fibrotic responses in PT-AT1a-KO mice 24 h or 7 days after renal ischemia-reperfusion (p<0.01). Our results suggest that AT1a receptors in the proximal tubule play an important role in the pathogenesis of renal ischemia-reperfusion injury, and thus may represent a therapeutic target in the future.
Abstract P602: Patiromer Decreased Aldosterone, Urine Albumin/Creatinine Ratio, and Blood Pressure in Patients with Chronic Kidney Disease and Hyperkalemia on RAAS Inhibitors: Results from OPAL-HK
Authors: Weir Matthew , Bakris George , Gross Coleman , Mayo Martha , Garza Dahlia , Stasiv Yuri , Yuan Jinwei , Berman Lance , Williams Gordon
Published: July 2021

Introduction:
Elevated aldosterone (ALD) is associated with chronic kidney disease (CKD) and cardiovascular (CV) complications. Patiromer, a nonabsorbed potassium (K
+
)-binding polymer, decreases serum K
+
(sK
+
) and may allow increased use of RAAS inhibitors (RAASi) in patients (pts) with CKD and hyperkalemia (HK). This analysis examined the effect of patiromer on ALD, urinary albumin/creatinine ratio (ACR), and blood pressure (BP) in pts with CKD on RAASi.

Methods:
OPAL-HK was a 2-part, phase 3 study in 243 CKD pts with sK
+
5.1–<6.5 mEq/L on RAASi. Pts received patiromer for 4 wks (Part A); pts with moderate-severe HK at baseline (sK
+
≥5.5 mEq/L) and sK
+
3.8–<5.1 at Part A wk 4 continued on patiromer (n=55) or switched to placebo (n=52) in the 8-wk withdrawal phase (Part B). RAASi were stable prior to and during Part A. Changes in ALD, ACR, and systolic BP/diastolic BP (SBP/DBP) were analyzed.

Results:
After 4 wks of patiromer sK
+
, serum ALD and urine ALD/creatinine decreased, while plasma renin activity (PRA) was unchanged; SBP, DBP, and ACR also declined (Table). Mean±SE changes (ng/dL) in serum ALD from Part A wk 4 to Part B wk 4 and to Part B wk 8 were 4.6±1.6 (p<0.01) and 5.7±1.8 (p<0.01) in the placebo and 0.9±1.0 (p=NS) and 0.2±0.8 (p=NS) in the patiromer groups, respectively. Compared with Part A wk 4, SBP (mm Hg) was further reduced at Part B wk 4 (3.1±2.1, p=NS) and Part B wk 8 (5.4±1.9, p<0.01) with maintained improvement in ACR in patiromer pts.

Conclusions:
Patiromer reduced both sK
+
and ALD (independent of PRA) in CKD pts with HK on RAASi. ALD reductions correlated with lower BP and ACR. Reduction in sK
+
may have lowered ALD possibly improving BP and ACR.
Abstract P627: The β3 Adrenergic Receptor is Partially Responsible for Anti-contractile Effect of Perivascular Adipose Tissue in Rat Mesenteric Resistance Arteries
Authors: Szasz Theodora , Matsumoto Takayuki , Wenceslau Camilla F , Webb R Clinton
Published: July 2021

In normal conditions, perivascular adipose tissue (PVAT) decreases contractile responses non-specifically in various vascular beds. This anti-contractile effect of PVAT is reduced in metabolic diseases and hypertension. The β3 adrenergic receptor (β3AR) is a G protein-coupled receptor expressed in adipocytes and involved in lipolysis and thermoregulation. We have previously demonstrated that chronic systemic infusion with a β3AR agonist induces white-to-brown adipose tissue remodeling and enhanced anti-contractile effects of PVAT via activation of cystathionine gamma lyase, enzyme involved in hydrogen sulfide synthesis. We hypothesized that the β3AR is directly mediating release of PVAT relaxing factors. Endothelium-intact mesenteric resistance arteries from adult male Wistar rats were used to measure contractile responses in the presence and absence of PVAT. In the absence of PVAT, the β3AR agonist CL316243 (1 nM-10 μM) did not directly induce relaxation of U46619-contracted arteries. In control conditions, norepinephrine (NE)-induced contraction was significantly reduced in the presence of PVAT. In contrast, incubation with the selective β3AR antagonist L-748337 (100 nM) led to a significant increase in NE-induced contraction in PVAT-intact arteries, while no change was observed in the absence of PVAT (figure). These data suggest that β3AR mediates the anti-contractile effect of PVAT on NE-induced contraction in resistance mesenteric arteries. Considering the structural and functional alterations of PVAT in hypertension, future studies may reveal a potential novel therapeutic approach via targeting of the PVAT β3AR pathway.