bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 659: Curcumin Ameliorates Cardiac Dysfunction in the Ovariectomized Diabetic mRen2.Lewis Rat by Inhibiting Renin Angiotensin System
Authors: VonCannon Jessica L , Jiao Yan , Kim-Shapiro Daniel , Varagic Jasmina
Published: July 2021

Diabetes is a well-recognized independent risk factor for the development of cardiovascular disease in women. Moreover, hypertension and loss of estrogen are additional complicating factors to diabetic heart disease. Curcumin, an active compound in the widely used spice turmeric, exerts therapeutic potential in diabetes mellitus; however, the underlying mechanisms are not fully understood. The present study was designed to investigate the potential of curcumin to ameliorate early cardiac dysfunction in insulin- and estrogen-depleted hypertensive mRen2.Lewis rats by altering the renin angiotensin system as one of the major contributors to the development of diabetic cardiomyopathy. Ovariectomy (OVX) was performed at 10 weeks of age and diabetes (D) subsequently induced at 11 weeks with streptozotocin (65 mg/kg). Only animals that showed hyperglycemia greater than 200 mg/dl were considered diabetic. OVX-D rats were given curcumin at a dose of 200 mg/kg/day (OVX-D & CUR; n=7) or vehicle (OVX-D & VEH; n=8) by gastric gavage starting two days after streptozotocin injection. Intact non-diabetic mRen2.Lewis rats served as controls (C; n=9). After four weeks, concomitant insulin and estrogen depletion induced systolic and diastolic dysfunction, indicated by decreased fractional shortening (FS; C: 60.0 ± 1.5 vs OVX-D & VEH: 43.7 ± 2.2 %; p<0.05) and Tissue Doppler velocity at the level of mitral annulus (e’; C: 75.0 ± 3.4 vs OVX-D & VEH: 58.6 ± 5.6 mm/s; p<0.05) that was associated with increased blood pressure (BP; C: 131 ± 3 vs 179 ± 2 mmHg; p<0.05), elevated plasma angiotensin II (Ang II; C: 20 ± 4 vs 32 ± 2 pg/ml; p<0.05), and cardiac expression of Ang II type 1 receptor (AT1; C: 100 ± 12 vs 206 ± 33 %; p<0.05). Curcumin treatment did not affect BP (164 ± 6 mmHg; p>0.05) but attenuated cardiac systolic (FS: 53 ± 3%, p<0.05) and diastolic dysfunction (e’: 74 ± 3 mm/s; p<0.05) while reducing AT1 expression (120 ± 12 %; p<0.05) in the diabetic heart. It also decreased plasma Ang II to the levels not different from the controls (21.6 ± 3 pg/ml; p>0.05). In conclusion, the present study suggests that curcumin treatment, in a blood pressure independent manner, may ameliorate early cardiac dysfunction in estrogen- and insulin-depleted mRen2.Lewis rats by reducing Ang II signaling pathway.
Abstract 060: POLDIP-2/NOX-4 Generates Hydrogen Peroxide that Impairs Myogenic Response of Afferent Arterioles from Mice with the Reduced Renal Mass Model of Chronic Kidney Disease
Authors: Li Lingli , Lai En Yin , Luo Zaiming , Solis Glenn , Griendling Kathy K , Taylor W.Robert , Welch William J , Christopher Wilcox S
Published: July 2021

Background:
Because we have found that myogenic contractions are stimulated by superoxide (O
2
.-
) but inhibited by hydrogen peroxide (H
2
O
2
), we tested the hypothesis that H
2
O
2
is the cause of the impaired myogenic responses of afferent arterioles from mice with the reduced renal mass (RRM) model of chronic kidney disease (CKD).

Methods:
Mice were subjected to 5/6 surgical nephrectomy or sham operations and fed 6% salt for 3 months. Single afferent arterioles were perfused, their diameter measured directly and O
2
.-
and H
2
O
2
measured by fluorescence microscopy.

Results:
The perfusion pressure of isolated afferent arterioles was increased from 40 to 80 mmHg to study myogenic responses. Arterioles from mice with RRM (vs sham) had a greater increase in O
2
.-
(21.2 ± 1.9 versus 11.3 ± 2.5%; p < 0.01) and especially H
2
O
2
(28.7 ± 3.7 versus 4.2 ± 0.4%, P<0.005), but a reduction in myogenic contraction (-1.7 ± 4.3 versus -14.4 ± 3.6%; p < 0.005) . Myogenic contractions were paradoxically reversed in afferent arterioles from mice with RRM after reduction in O
2
.-
by PEG-SOD (+3.3 ± 1.5 versus -1.7 ± 4.3%, P<0.05) or deletion of p47
phox
(+2.5 ± 1.4 versus -1.7 ± 4.3%, P<0.05). In contrast, myogenic responses were increased even above the levels of shams in arterioles from mice with RRM after reduction in H
2
O
2
by PEG-catalase (-19.1 ± 1.6 versus -1.7 ± 4.3%, P<0.005) or transgenic overexpression of catalase in smooth muscle cells (-10.7 ± 1.3 versus -1.7 ± 4.3%, P<0.01). Gene expression for NOX-4 and POLDIP-2 (main source of H
2
O
2
) was increased 40-50% (P<0.05) in individual afferent arterioles from mice with RRM. Moreover, the myogenic contractions in the arterioles from POLDIP-2+/- mice with RRM were similar to POLDIP-2+/- with sham operations (-7.7 ± 0.9 versus -8.0 ± 0.6, P=NS).

Conclusions:
Afferent arterioles from mice with RRM had severely impaired myogenic responses that were attributed to increased H
2
O
2
generation from POLDIP-2/NOX-4 that may therefore be novel targets to maintain autoregulation and protect kidneys from barotrauma in CKD.
Abstract 096: Sequential Activation of Nox1 and Gremlin1 Leads to Endothelial Proliferation in Human Pulmonary Arterial Hypertension
Authors: Al Ghouleh Imad , Sahoo Sanghamitra , Meijles Daniel N , Amaral Jefferson H , Sembrat John , Rojas Mauricio , Goncharov Dmitry A , Goncharova Elena A , Pagano Patrick J
Published: July 2021

Pulmonary arterial hypertension (PAH) is a rapidly degenerating and devastating disease of increased pulmonary vessel resistance leading to eventual right heart failure. Until now, palliative modalities have targeted the reduction of vascular tone with little success. Recent studies have delved into the mechanisms regulating increased pulmonary vascular resistance: aberrant vascular remodeling and occlusion. However, little is known of the molecular mechanisms responsible for endothelial proliferation, a root cause of PAH-associated vascular remodeling. We provide the first evidence to our knowledge of an upregulation of NADPH oxidase 1 (Nox1) at the transcript and protein (2.1±0.62 -fold,
P
< 0.05) level in resistance vessels from PAH vs. non-PAH subjects. This coincided with an increase in bone morphogenetic protein (BMP) antagonist Gremlin1 protein expression (2.3±0.47 [[Unable to Display Character: –]]fold vs. non-PAH,
P
< 0.05) and reactive oxygen species (ROS) production (iodonium-inhibitable hydrogen peroxide production: 0.69±0.06 vs. 0.43±0.032 nmol/min/mg protein for PAH vs. non-PAH, respectively,
P
< 0.05). In vitro studies in human pulmonary artery endothelial cells (HPAEC) demonstrate that hypoxia (24 hr, 1 % O
2
) drives Nox1 subunit expression (Nox1 protein: 1.4±0.075-fold vs. normoxia,
P
< 0.05), assembly and oxidase activity (superoxide production, nmol/min/mg protein: 14.0±1.9 vs. 6.00±0.94 for normoxia,
P
< 0.01) leading to elevation in sonic hedgehog (SHH; 1.5±0.011 fold,
P
< 0.05) and Gremlin1 (1.90±0.32-fold,
P
< 0.01) expression. Nox1 gene-silencing in hypoxia-exposed HPAEC abrogated this cascade. Moreover, hypoxia-induced endothelial cell proliferation (1.18±0.038-fold vs. normoxia,
P
< 0.05) was attenuated with loss of either Nox1 or Gremlin1. Finally, incubation of normoxic HPAEC with conditioned media from hypoxia-exposed HPAEC resulted in increased proliferation, which was abrogated by Nox1 suppression of donor cells. Together these data support a Nox1-Gremlin1 signaling axis in pulmonary vascular endothelium that is likely to contribute to pathophysiological endothelial proliferation and the progression of pulmonary hypertension. The findings also support targeting of Nox1 as a viable therapeutic option to combat PAH.
Abstract 120: Increased Mitochondrial Superoxide in the Brain, but not Periphery, Sensitizes Mice to Angiotensin II-Mediated Hypertension
Authors: Case Adam J , Tian Jun , Zimmerman Matthew C
Published: July 2021

Mitochondrial superoxide (O
2
[[Unable to Display Character: ●]]-
) is a critical signaling intermediate in angiotensin II (AngII)-dependent hypertension. However, it remains unknown if increased mitochondrial O
2
[[Unable to Display Character: ●]]-
flux in the absence of hypertensive stimuli is sufficient to affect blood pressure. We hypothesized that elevated levels of systemic mitochondrial O
2
[[Unable to Display Character: ●]]-
leads to increased blood pressure and exacerbates AngII-induced hypertension. To test this, we utilized a conditional mouse model of manganese superoxide dismutase knock-out (MnSOD
lox/lox
), which we have shown amplifies steady-state mitochondrial O
2
[[Unable to Display Character: ●]]-
levels in all cell types examined. When combining the MnSOD
lox/lox
mouse with a tamoxifen-inducible cre recombinase expressed by the systemic ROSA26 promoter, MnSOD was knocked-down (30-98%, p<0.05) in peripheral organs after intraperitoneal tamoxifen administration. However, no changes in MnSOD protein levels were observed in the brain. Interestingly, mean arterial pressure (MAP) and heart rate were unaffected by the loss of MnSOD in these peripheral tissues, and moreover, upon subcutaneous infusion with AngII (400 ng/kg/min) both wild-type and MnSOD knock-down mice exhibited a similar increase in MAP. Due to these unexpected results, we examined the role of elevated mitochondrial O
2
[[Unable to Display Character: ●]]-
levels specifically in the brain subfornical organ (SFO) by targeting the loss of MnSOD to this critical AngII-sensitive region. We observed a 60% decrease of MnSOD (p<0.05) with concomitant increase in mitochondrial O
2
[[Unable to Display Character: ●]]-
, as measured by MitoSox Red fluorescence, in the SFO following adenovirus-mediated gene transfer of cre recombinase to the SFO in MnSOD
lox/lox
mice. Intriguingly, these mice demonstrated no change in baseline MAP (92.8 ± 0.4 mmHg in knock-down vs. 93.1 ± 0.4 mmHg in control mice), but did show a significant elevation in MAP upon peripheral AngII infusion (MAP
max
= 137.8 ± 2.7 mmHg in knock-down vs. 128.3 ± 3.3 mmHg in control mice, p<0.05). Taken together, our data suggest that increased mitochondrial O
2
[[Unable to Display Character: ●]]-
in the absence of hypertensive stimuli is not sufficient to alter baseline hemodynamics, but dysregulation of mitochondrial redox status in the SFO may be a predisposition to increased responsiveness to hypertensive stimuli, such as AngII.
Abstract MP05: Knockdown of Gamma-adducin Expression Impairs the Myogenic Response of the Cerebral and Renal Arterioles
Authors: Fan Fan , Pabbidi Mallikarjuna R , Ge Ying , Roman Richard J
Published: July 2021

We recently identified a region on chromosome 1 containing 15 genes that rescues the impaired myogenic response in the afferent arteriole (Af-art) and the development of renal injury in Fawn Hood Hypertensive (FHH) rats. We also found an inactivating K572Q mutation in the gamma-Adducin (Add3) gene in FHH rats in this region that may play a causal role. To test this hypothesis, the present study examed the effect of knockdown of the expression of Add3 with DsiRNA on the myogenic response of renal and cerebral arterioles. A newly designed 27-mer Add3 DsiRNA blocked the expression of the Add3 protein in 293 cells and reduced Add3 mRNA expression in a dose-dependent manner up to 75% in cultured middle cerebral arteries (MCA). The inner diameter of MCA and renal Af-art 36 hours after co-transfection of Add3 DsiRNA dilated by 9 ± 2% and 4 ± 3%, respectively, in response to an elevation in transmural pressure from 60 to 140 mmHg. In contrast, these vessels still constricted normally by 11± 2% and 10 ± 1% in vessels transfected with scrambled siRNA. Add3 DsiRNA had no effect on the vasoconstrictor response of the Af-art to NE (10-7 M). The large conductance calcium sensitive potassium (BK) current was 5-fold higher in vascular smooth muscle cells (VSMC) freshly isolated from the MCA that were transfected with Add3 DsiRNA as indicated by the appearance of SiGLO red fluorescence compared with that seen in non-transfected cells. Administration of IBTX normalized the elevated BK channel current recorded from VSMC transfected with Add3 DsiRNA, but it had little effect in non-transfected cells. These results indicate that knockdown of the expression of Add3 impairs the myogenic response of both MCA and Af-art and it is associated with an elevation in BK channel activity. It also supports the hypothesis that the K572Q mutation of Add3 found in FHH rats may play a causal role in the impaired myogenic response and autoregulation of renal and cerebral blood flow by elevating BK channel activity in VSMC.
Abstract MP08: Syndecan-1 is Involved in Osteoprotegerin-induced Vascular Dysfunction
Authors: Montezano Augusto C , Neves Karla B , Lopes Rheure A , Leckerman Susan , Strembitska Anastasiya , Jenkins Carol , Thomson Jacqueline , Graham Delyth , Touyz Rhian M
Published: July 2021

Osteoprotegerin (OPG), an inhibitor of vascular calcification, has pleiotropic vascular effects independently of its actions on calcification. OPG has been associated with vascular inflammation and remodelling and may be important in cardiovascular disease where OPG levels may be elevated. Molecular mechanisms and functional consequences of OPG stimulation in the vasculature are unclear. We propose that syndecan-1, a membrane glycoprotein, may be important and that reactive oxygen species (ROS) play a role in OPG signalling. Vascular reactivity of resistance arteries from WKY rats was studied by wire myography in the presence or absence of OPG (50 ng/mL) and/or synstatin (SSNT - 10-6M - syndecan-1 inhibitor). Rat endothelial cells (EC) and vascular smooth muscle cells (VSMC) were studied. Levels of ROS were measured by chemiluminescence, Amplex Red (H2O2) and ELISA (nitrotyrosine; peroxynitrite - ONOO-). Protein oxidation and levels were measured by immunoblotting. Exposure of resistance arteries to OPG induced endothelial (decreased relaxation to acetylcholine) and VSMC (decreased relaxation to sodium nitroprusside - SNP) dysfunction, as well as, increased contraction to phenylephrine. All responses were blocked by SSNT, N-acetylcisteine (antioxidant) and ML171 (Nox inhibitor). In EC, OPG-induced ROS production (240±46.1% increase vs. veh, p<0.05) was blocked by SSNT. OPG decreased H2O2 production/release (61±5.4% vs. veh) and increased eNOS Thr 495 phosphorylation (inhibitory site) (100±24% vs. veh, p<0.05). In VSMC, OPG increased H2O2 (69±3%) and ONOO- (43±12%) levels, protein oxidation (61±15%), Rho kinase (200±39%) and myosin light chain activation (55±3%) (all vs. veh, p<0.05). Increase in OPG-induced ONOO- levels was exacerbated by SNP (130±16% vs. veh, p<0.05), a nitric oxide donor. In conclusion, vascular dysfunction elicited by OPG is mediated by syndecan-1 and ROS. Whether syndecan-1 also impacts on OPG-sensitive calcification is unclear. Our data identify a novel molecular mechanism through syndecan- 1/ROS that may underlie injurious effects of OPG.
Abstract MP09: Adrenal-specific Deletion of TASK Channels Evokes Normal-Renin Hypertension
Authors: Guagliardo Nick A , Le Thu H , Bayliss Douglas A , Breault David T , Barrett Paula Q
Published: July 2021

Objectives:
Dysregulation of aldosterone (Aldo) production is predicted to evoke major features of idiopathic primary hyperaldosteronism (IHA): low renin, elevated blood pressure and suppressed control by high Na. We have previously demonstrated in mice that global deletion of background TWIK-related acid-sensitive K (TASK) channels (TASK-1, TASK-3) effect a ~20mV decrease in the membrane potential of Zona Glomerulosa (ZG) cells to produce frank autonomous overproduction of Aldo, low renin, and hypertension (HT), mimicking the salient features of human IHA. In the current study, we ask if specific deletion of TASK channels in ZG cells is sufficient to produce hyperaldosteronism and the predicted sequela or if extra-adrenal deletion of TASK channels is required.

Design and Methods:
We generated a trigenic mouse-line (
AS
+Cre
::TASK-1
ff
::TASK-3
ff
, zT1T3KO) in which TASK-1 and TASK-3 subunits were specifically deleted in ZG cells. The renin-angiotensin-aldosterone system (RAAS) was evaluated in mice housed in metabolic cages and stabilized on various salt diets. Urinary Aldo concentration was measured and normalized to creatinine (ng Aldo/mg creatinine; 24 hr. urine collection). Blood pressure was recorded in conscious, freely moving mice using radio telemetry, and plasma renin concentration was measured from tail vein sampling.

Results:
Overproduction of aldosterone on normal-salt diet (0.3% Na) was modest in zT1T3KO mice compared to littermate controls (WT; WT 9.4; KO 11.8 ng/mg, 1.25-fold). Suppression of Aldo production by high-salt (2% Na) was blunted, exaggerating the difference in Aldo production between genotypes (WT 3.0; KO 7.4 ng/mg, 2.43-fold). zT1T3KO mice were hypertensive (mean MAP: WT 103.5; KO 113.1 mmHg), yet renin levels remained normal. Neither hyperaldosteronism nor HT could be corrected by angiotensin II receptor blockade, suggesting overproduction of Aldo and HT are independent of RAAS.

Conclusions:
Limiting TASK deletion to ZG cells results in normal renin HT driven by modest autonomous hyperaldosteronism, a stark contrast to the phenotypic features of IHA recapitulated by global TASK deletion. Together these mouse models provide insight into the role of ZG- vs extra-adrenal-dysfunction in the pathology of IHA.
Abstract P075: Stroke Volume and Visceral Fat Drive Differences in Blood Pressure Between Two Generations: A Population-Based Study of Adolescents and Their Parents
Authors: Syme Catriona A , Abrahamowicz Michal , Leonard Gabriel , Perron Michel , Richer Louis , Veillette Suzanne , Gaudet Daniel , Paus Tomas , Pausova Zdenka
Published: July 2021

Excess total body fat (TBF) and visceral fat (VF) are major risk factors of hypertension. Blood pressure (BP) increases with age, as do TBF and VF. Here we investigated whether TBF and VF contribute to BP differences between adolescents and adults. A population-based sample of adolescents (n=933, 12-18 years) and their parents (n=429, 38-65 years) was studied as part of the Saguenay Youth Study. In all participants, beat-by-beat values of SBP, DBP and underlying hemodynamic parameters (heart rate, stroke volume [SV] and total peripheral resistance) were obtained with a Finometer during a 52-minute protocol mimicking daily life activities and including posture and math-stress tests. TBF was assessed by bioelectrical impedance and VF was examined by magnetic resonance imaging. SBP was higher in parents than adolescents by an average of 10.2±0.3 mmHg in males and 9.1±0.3 mmHg in females (p<0.0001 for both sexes). DBP differed minimally throughout the protocol (p=0.3 and 0.1, respectively). In males and females, respectively, the ‘generation’ differences in SBP were reduced to 6.0±0.1 and 4.3±0.1 mmHg when adjusted for height and TBF (p<0.0001 for both), and were further reduced to 1.9±0.1 and 2.5±0.2 mmHg when additionally adjusted for VF (p=0.1 and 0.02). Of the underlying hemodynamic parameters, only SV was higher in parents than adolescents (by 46±2 ml in males and 39±2 ml in females, p<0.0001 for both). Again, the ‘generation’ differences in SV were reduced to 23±1 (males) and 20±1 ml (females) when adjusted for height and TBF (p<0.0001 for both sexes), and were further reduced to 11.8±0.6 and 15.7±0.8 ml when additionally adjusted for VF (p<0.0001 for both sexes). These results suggest that the transition from adolescence to middle-aged adulthood is associated with an increase in SBP (but not DBP), which is driven mainly by SV augmentation. They also suggest that VF contributes to the generational differences in both SBP and SV above and beyond the contribution of TBF, despite VF being a relatively small fraction of TBF. The co-occurrence of these differences in VF, SV and SBP may be related to sympathoactivation and renal handling of sodium and water reabsorption; further research is required to confirm this possibility.
Abstract P091: Vitamin D Supplementation Inhibits Blood Pressure and Uterine Artery Resistance Induced by Autoantibodies to the AT1 Receptor
Authors: Faulkner Jessica L , Cunningham Mark W , Amaral Lorena M , Ibrahim Tarek , Cornelius Denise C , Thomas D'Andrea S , Wallukat Gerd , Dechend Ralf , LaMarca Babbette
Published: July 2021

Studies in our lab have previously shown that Vitamin D supplementation in the RUPP rat model of preeclampsia lowers blood pressure and reduces autoantibodies to the AT1 receptor (AT1-AA). Therefore, we sought to determine if the effects of Vitamin D supplementation to inhibit endothelial dysfunction and hypertension during pregnancy were mediated by AT1-AA reduction. We hypothesized that Vitamin D supplementation to AT1-AA-induced hypertensive pregnant rats would reduce anti-angiogenic factor soluble FMS-like tyrosine kinase-1 (sflt-1) and uterine artery resistance index (UARI) while improving blood pressure (MAP). Purified rat AT1-AA was infused (1:40) into Sprague-Dawley rats via miniosmotic pump from gestational day (GD) 12 to GD19. On GD14-18 we administered Vitamin D2 or D3 (VD2 or VD3) to AT1-AA rats (50ul/ml) by oral gavage. On GD18 indwelling carotid catheters were inserted and UARI assessed by Doppler sonography and MAP was measured on GD19. Consistent with previous studies, MAP was 119.0 mmHg in AT1-AA infused pregnant rats. MAP was unchanged with VD2 treatment at 121.7 mmHg (n=3), however, reduced to 109.3 mmHg (n=3) in AT1-AA+VD3 rats. Pup and placental weights were 1.79 and 0.46 g (n=3), respectively, in AT1-AA rats and were increased with VD2 treatment to 2.33 and 0.54 g (n=3) and to 2.39 and 0.56 g (n=3) in AT1-AA+VD3 rats. UARI was 0.577 (n=2) in AT1-AA rats but reduced with VD2 treatment to 0.491 (n=3) and VD3 to 0.452 (n=2). Plasma sflt-1, which is increased with AT1-AA infusion, was measured with ELISA and was >1050 pg/ml in AT1-AA rats (n=3) and greatly reduced in both AT1-AA+VD2 at 42.3 pg/ml (n=2) and AT1-AA+VD3 at 241.0 pg/ml (n=3). Our preliminary data demonstrate that Vitamin D supplementation improves uterine artery vascular resistance and sflt-1 and that these are potential mechanisms for improving fetal weight and hypertension that is induced by AT1-AA during pregnancy.
Abstract P096: Vascular Protein Oxidation and Redox Proteomics in Human Hypertension
Authors: Tsiropoulou Sofia , Montezano Augusto C , Scott Alan , Burchmore Richard J , Touyz Rhian M
Published: July 2021

Oxidative stress has been implicated in the pathophysiology of hypertension (HTN) through redox-sensitive processes that cause vascular damage. Despite recent advances in the field of vascular redox signalling in HTN, it still remains unclear exactly how ROS cause vascular injury. We hypothesise that regulation of redox-sensitive protein tyrosine phosphatases (PTP) through post-translational oxidative modification, is impaired in HTN where ROS levels are increased. Vascular smooth muscle cells (VSMC) from small arteries of normotensive (NT) and hypertensive (HT) individuals were stimulated with AngII (10-7 M) and ET-1 (10-7 M). Irreversible oxidation of proteins and PTPs was assessed by oxyblot and immunoblotting, respectively. Differential gel electrophoresis (DiGE) and CyDye thiol labelling were employed for screening of reversibly oxidised proteome. Irreversible protein oxidation was not affected by AngII or ET-1 in VSMCs from NT and HT subjects. PTP hyperoxidation tended to increase in VSMCs from NT upon stimulation with AngII (FC=2.12 at 60min) and ET-1 (FC=1.60 at 60min), whereas a similar trend was observed only after AngII treatment (FC=1.38 at 60min) in HTN (p>0.05). Proteomic data, filtered for FC>2, detected 2051 spots with 1899 (92.5%) being equally oxidised between NT and HT. In addition, oxidation of 57 (2.9%) spots was increased, while 95 (4.6%) were decreased in HT. Candidate proteins exhibiting consistent changes across three experimental replicates included β-actin (FC=-2.86), annexin A1 (-2.23), galectin-1 (-1.67), FK506 binding protein (-2.35) and polymerase I and transcript release factor (PTRF, -1.92). Stimulation with AngII altered the redox status in 2-3% of proteins, both in HT and NT. However, vimentin was the only target changing consistently across the replicates (FC=2.48). Our findings indicate that pro-hypertensive agents may not impact significantly on irreversible protein and PTP oxidation in health and disease, but may have effects on reversible oxidation. Our proteomic data, in agreement with our previous rat studies, support decreased reversible thiol oxidation in HTN. Moreover, these novel findings identify differentially oxidised proteins which may contribute to oxidative vascular injury in HTN.
Abstract P106: The Role of Inflammasomes and Angiotensin II Type 1 Receptor in the Pressor Responses of Aged Mice to Angiotensin II
Authors: Dinh Quynh N , Drummond Grant R , Kemp-Harper Barbara K , Diep Henry , Robertson Avril A , Cooper Matthew A , Sobey Christopher G , Chrissobolis Sophocles
Published: July 2021

Introduction:
The prevalence of hypertension increases with age. Chronic low-grade inflammation commonly occurs with ageing, and inflammasomes are important initiators of inflammatory responses. We tested whether aged mice have enhanced pressor responses to angiotensin II (Ang II) and whether this is associated with exaggerated pro-inflammatory and vascular contractile responses. We also tested whether MCC950, a NLRP3 inflammasome inhibitor, reduces blood pressure (BP) in Ang II-treated aged mice.

Methods:
Young (8-12 weeks) and aged (24-30 months) male C57Bl6 mice were left untreated, or either treated with vehicle or a slow-pressor dose of Ang II (0.28 mg/kg/day) for 28 days. Another group of aged mice were treated with either Ang II + saline or Ang II + MCC950 (10 mg/kg/day) for 10 days. We measured systolic BP, mRNA expression of inflammatory markers and components of the renin-angiotensin system, and vascular contractile responses.

Results:
In young mice, Ang II caused a gradual increase in BP (final BP: 141.6 ± 8.3 mmHg), whereas BP increased by ~20 mmHg from baseline in aged mice, and continued to increase for 28 days (final BP: 155 ± 12.4 mmHg) (n=8-9, P<0.05). Ageing alone increased renal expression of AT1a receptors, NLRP3, Caspase-1, IL-1β, IL-33, CCR2, CCL7 and CCL8 by at least 1.5-fold (n=7-8, all P<0.05). Maximum contractile responses of mesenteric artery were 1.8-fold greater to Ang II and 1.2-fold greater to phenylephrine in aged vs young mice (n=4, both P<0.05). BP was not different between Ang II + saline-treated aged mice (BP: 138.8 ± 6.8 mmHg) and Ang II + MCC950-treated aged mice (BP: 144.7 ± 9.6 mmHg) (n=6-7, P>0.05).

Conclusions:
Aged mice have enhanced pressor responses to Ang II and this is associated with exacerbated pro-inflammatory and vascular contractile responses. The NLRP3 inflammasome does not appear to contribute to Ang II-induced hypertension in aged mice.
Abstract P164: White-coat Hypertension is a Factor Relating Postural Blood Pressure Dysregulation and Cardiovascular Risks
Authors: Tabara Yasuharu , Igase Michiya , Miki Tetsuro , Kohara Katsuhiko
Published: July 2021

Backgrounds:
Postural blood pressure (BP) dysregulation particularly orthostatic hypotension is a phenomenon that is frequently observed in elderly persons and has been reported to be a prognostic factor for incidence of cardiovascular diseases and mortality. White-coat and masked hypertension are another indices of blood pressure dysregulation and were also known to be a risk factor for cardiovascular outcomes. However, relationship between these common phenomena is yet unclear. Here we conducted a cross-sectional study to clarify the relationships.

Methods:
Study subjects were 818 general persons. Homed BP was calculated from ambulatory monitored BPs as a mean of BPs measured during 1 hour after wake up. Orthostatic BP change was measured at 1 and 3 minutes after standing up and a maximum BP difference was used in the analysis.

Results:
Home-to-clinic SBP differences were linearly and inversely associated with orthostatic SBP change (r=-0.321, p<0.001). Therefore, white-coat hypertensive subjects (10.3%, -9.3±13.3 mmHg) showed larger orthostatic BP decline than normotensive subjects (30.9%, -3.0±11.1 mmHg) and masked hypertensive subjects (24.7%, -0.4±12.1 mmHg, p<0.001). Home-to-clinic SBP differences (β=-0.150, p<0.001), but not orthostatic SBP change (β=-0.046, p=0.169), was significantly associated with carotid hypertrophy independently of basic covariates including clinic SBP.

Conclusion:
Home-to-clinic SBP differences may be partially involved in the prognostic significance of orthostatic hypotension.
Abstract P219: Differences in Phosphoproteins in Rodent versus Human Hearts: Implications for Translational Studies of Hypertensive Heart Disease
Authors: Danziger Robert S , Kotlo Kumar , Samarel Allen , Chen Hua , Aldstadt Jared
Published: July 2021

Background:
Rodent models are commonly used to study hypertensive heart disease. Several recent studies have probed the level of correlation between specific signaling pathways and proteins in human and rodents. Current evidence is overwhelming that protein phosphorylations play a key role in cardiac remodeling.

Methods:
Left ventricular tissue samples were obtained from human systolic failing (n=5) and control (n=5) hearts and 3 rat models of hypertensive heart failure (aortic banding, Dahl salt-sensitive, and spontaneously hypertensive rats (SHR)) and corresponding controls. Total proteins were extracted and and phosphoenrichment performed. Phosphoproteins were separated by 2D-DIGE with Cydye staining. Gel images were registered and rectified for composite analysis and statistical comparisons using pixel intensity. Phosphoproteins were identified by MALDI-TOF/TOF Mass Spectrometry.

Results:
The patterns of overall protein abundance from normal and failing hearts were not statistically different. However, when the composite of human hearts were compared with composite patterns of phosphoproteins in normal and failing rodent hearts, there were profound differences in the phosphoprotein patterns in 26% of pixels in registered images (P < 0.05). Targeted pair wise analyses showed differences (P < 0.05) between human and rodent hearts for troponin T, myosin light chain, peroxiredoxin, and haptoglobin phosphorylations.

Conclusions:
Together, the present results indicate significant differences in cardiac phosphoproteins in human versus rodent heart and the importance of confirming findings from rodent studies in humans for translational studies of kinases, phosphatases, and phosphoproteins. This may specifically relate to studies of phosphorylation of myosin light chain and troponin.
Abstract P227: Safety and Efficacy of Losartan/hydrochlorothiazide Combination in Elderly Patients With Morning Hypertension
Authors: Uchiwa Hiroki , Kai HIsashi , Ueda Tamenobu , Anegawa Takahiro , Aoki Yuji , Iwmoto Yoshiko , Fukuda Kenji , Fukumoto Yoshihiro
Published: July 2021

Background:
Cardiovascular events occur most frequently in the morning. Elevation of blood pressure (BP) in the early morning (morning hypertension) is characteristic feature of hypertension in the elderly, and is attributed to cardiovascular events. However, treatment of morning hypertension has not been established, especially in the elderly patients. A combination of an angiotensin II receptor blocker (ARB) and hydrochlorothiazide (HCTZ) is a desirable choice of treatment for uncontrollable hypertension by antihypertensive monotherapy.

Purpose:
The aim of this study was to compare the safety and effectiveness between an ARB/HCTZ combination therapy and high-dose ARB therapy in the elderly (75 years or more) and younger (less than 75 years) patients.

Methods:
This study enrolled 201 (66 elderly and 135 younger) on-treatment patients having morning hypertension evaluated by home BP self-measurement. Patients were randomly assigned to receive 50mg-losartan/12.5mg-HCTZ combination (Combination) or 100mg-losartan (High-dose) therapy.

Results:
During the 3-month treatment, the incidence of adverse events of Combination and High-dose therapies was similar in the elderly and younger patients. In the elderly patients, Combination therapy induced greater morning systolic BP reduction than High-dose therapy, whereas the two therapies showed the similar effects on estimated glomerular filtration rate (eGFR), serum K, and uric acid, as well as in younger patients (Table).

Conclusions:
ARB/HCTZ combination therapy was safe and more effective for controlling morning hypertension than high-dose ARB in the elderly patients, as seen in younger patients.
Abstract P238: High Fat Diet-induced Obesity Disrupts Vascular Homeostasis in Both Kidney and Retina: Role of Epoxyeicosatrienoic Acids
Authors: Elmarakby Ahmed A , Katary Mohamed A , Mohamed Islam N , El-Remessy Azza B
Published: July 2021

Obesity-induced vascular inflammation is considered an early and common pathological change for the development of microvascular complications including retinopathy and nephropathy. We have previously demonstrated that obesity down-regulated renal cytochrome P450 epoxygenase and decreased epoxyeicosatrienoic acids (EETs) levels in kidney as well as triggered retinal expression of the pro-inflammatory thioredoxin interacting protein (TXNIP) that coincided with vascular inflammation. The aim of this work is to examine the impact of obesity-induced reduction in EETs levels on TXNIP-inflammasome activation. Because EETs are quickly hydrolyzed by the soluble epoxide hydrolase (sEH) enzyme to inactive metabolites, we use sEH gene deleted mice (Ephx2 -/-) as a model with high EETs levels. WT and Ephx2 -/- were fed normal (14 % fat) or high fat diet (HFD, 60 % fat) for three months. HFD treatment down-regulated cyp2c44, the main epoxygenase for EETs production, and decreased EETs levels in kidney of obese mice and these changes were associated with podocyte loss and increased podocalyxin excretion as markers of glomerular injury. Although HFD treatment decreased EETs levels in Ephx2 -/- mice, it remained significantly higher than obese WT mice. HFD impaired endothelial function and induced TXNIP-inflammasome activation evident by increases in NOD-like receptor-3 (NLRP3) and interleukin-1β (IL-1β) in both retina and kidney. In parallel, HFD also increased leukostasis, retinal vascular permeability and development of acellular capillary, hall mark of ischemia in WT but not in TXNIP-/-. Restoring EETs levels in Ephx2 -/- mice improved endothelial function and was associated with decreased TXNIP-mediated inflammasome activation in the kidney of obese mice. Our data suggest that diet-induced obesity causes homeostatic imbalance by down-regulation of the anti-inflammatory epoxygenase/EETs levels and increasing the inflammatory TXNIP expression resulting in vascular injury in both retina and kidney.
Abstract P259: Endothelial Acid Sphingomyelinase Gene Determines Inflammasome Activation and Atherosclerotic Lesions in Carotid Arteries During Hypercholesterolemia
Authors: Xia Min , Bioni Krishna M , Chen Yang , Li Xiang , Pitzer Ashley L , Zhang Yang , Li Pin-Lan
Published: July 2021

Nucleotide oligomerization domain (NOD)-like receptor protein with pyrin domain containing 3 (Nlrp3) inflammasome has been reported to be activated by atherogenic factors, thereby triggering endothelial injury and consequent atherosclerotic lesions in the arterial wall. However, the mechanism activating and regulating Nlrp3 inflammasomes remains poorly understood. The present study tested whether membrane raft (MR) signaling platforms associated with acid sphingomyelinase (ASM) and its product ceramide (Ce) importantly contribute to the activation of Nlrp3 inflammasomes and atherosclerotic lesions during hypercholesterolemia (HC). By confocal microscopy and biochemical analyses, we demonstrated the formation and activation of Nlrp3 inflammasomes in the intima of the carotid arteries of Asm
+/+
mice with HC (as shown by a 2-fold increase in caspase-1 activity and a 6-fold enhancement of IL-1β positive stain areas), but not in Asm
-/-
mice. In endothelium-specific ASM transgenic mice (EC-Asm

trg

), this inflammasome formation and activation were enhanced. Correspondingly, HC-induced increases in IL-1β production, ASM expression, Ce level and MR-gp91

phox

clustering in the carotid intima were abolished in Asm
-/-
mice, but enhanced in EC-Asm

trg

mice. Functionally, endothelium-dependent vasodilation (EDVD) in carotid arteries
in vivo
(by ultrasound flowmetry) and
in vitro
(in perfused artery) was impaired by HC in Asm

+/+

mice by 33% and 54%, respectively. This endothelial dysfunction was not observed in Asm
-/-
mice. The endothelial tight junction protein, ZO-1 was reduced by HC in both Asm
+/+
and EC-Asm

trg

mice, but not in Asm
-/-
mice. It was also found that HC-increased neointimal formation, T-cell infiltration, and fibrosis in 2-week partially ligated carotid arteries (PLCA) occurred in Asm
+/+
mice, but not in Asm
-/-
mice with HC. EC-Asm

trg

mice even exhibited more severe inflammatory and atherosclerotic lesions. All these results suggest that Asm gene and related MR clustering are essential to endothelial inflammasome activation and dysfunction in carotid arteries, ultimately determining the extent of atherosclerotic lesions.
Abstract 031: Diastolic Blood Pressure, Coronary Artery Calcium, and Cardiac Outcomes in the Multi-ethnic Study of Atherosclerosis
Authors: McEvoy John W , Rahman Faisal , Al Rifai Mahmoud , Blaha Michael , Nasir Khurram , Budoff Matthew , Psaty Bruce , Post Wendy , Blumenthal Roger
Published: July 2021

Diastolic blood pressure (BP) has a J-curve relationship with coronary heart disease and death. Because this association is thought to reflect reduced coronary perfusion at low diastolic BP, our objective was to test whether the J-curve is most pronounced among persons with coronary artery calcium. Among 6,811 participants from the Multi-Ethnic Study of Atherosclerosis, we used Cox models to examine if diastolic BP category is associated with coronary heart disease events, stroke, and mortality. Analyses were conducted in the sample overall and after stratification by coronary artery calcium score. In multivariable-adjusted analyses, compared with diastolic BP of 80 to 89 mmHg (reference), persons with diastolic BP <60 mmHg had increased risk of coronary heart disease events (HR 1.69 [95% confidence interval 1.02-2.79]) and all-cause mortality (HR 1.48 [95% confidence interval 1.10-2.00]), but not stroke. After stratification, associations of diastolic BP <60 mmHg with events were present only among participants with coronary artery calcium >0. Diastolic BP <60 mmHg was not associated with events when coronary artery calcium was zero. We also found no interaction in the association between low diastolic BP and events based on race. In conclusion, diastolic blood pressure <60 mmHg was associated with increased risk of coronary heart disease events and all-cause mortality in the sample overall, but this association appeared strongest among individuals with elevated CAC; suggesting that added caution may be needed when pursuing intensive BP treatment targets among persons with subclinical atherosclerosis.
Abstract 097: Knockout of Matrix Metalloproteinase 9 Protects Against Hypertension-induced Renal Disease in Hypertensive Dahl S Rats
Authors: Zhang Chao , Mims Paige N , Zhu Tongyu , Fan Fan , Roman Richard J
Published: July 2021

Matrix metalloproteinase 9 (MMP9) is a member of gelatinase family of enzymes with potentially opposing actions on tissue fibrosis (i.e. the degradation of extracellular matrix). Our previous study showed that two nonselective MMP inhibitors, XL081 and XL784, which inhibit MMP2, 9, 13 and Adam10 could delay and even reverse the development of renal fibrosis in hypertensive Dahl Salt sensitive (SS) rats. However, the specific role of MMP9 to the development of hypertensive nephropathy in MMP9 knockout (KO) rat models is unknown.

In the present study, MMP9 KO rats were created on the SS genetic background using a CRISPR/Cas 9 system and the effect of KO was verified in this model. The systolic pressure, diastolic pressure and mean blood pressure (MAP) were similar in 12 weeks old MMP9 KO (n=6) and SS rats (n=9) fed a low salt diet (145 ± 3 vs. 148 ± 2mmHg; 111 ± 2 vs. 107 ± 2mmHg; 128 ± 2 vs. 126 ± 2mmHg). MAP increased to 180 ± 4 vs. 154 ± 3mmHg in SS rats versus MMP9 KO rats fed 8% high salt (HS) diet for 3 weeks. Proteinuria increased from 196 ± 18 mg/day to 718 ± 61mg/day in HS treated SS rats (n=9). It was significantly reduced in HS treated MMP9 KO rats (211 ± 30mg/day, n=6). The degree of glomerular injury (2.88 ± 0.08 vs. 3.52 ± 0.02), interstitial fibrosis (4.57 ± 0.35% vs. 10.45 ± 0.55%), vascular wall-to-lumen ratio (0.63 ± 0.04 vs. 1.22 ± 0.08) and protein cast area (6.40 ± 0.07% vs. 20.27 ± 2.65%) were all significantly reduced in MMP9 KO rats (n=6) versus the corresponding values in SS rats (n=6) fed 8% HS diet for 3 weeks. Autoregulation of renal blood flow (RBF) to elevations in perfusion was impaired in SS rats prior to the development of hypertension, for RBF rose by 20.6 ± 3.6% (n=8) when MAP was increased from 110 to 150 mmHg. Autoregulation of RBF was restored in MMP9 KO rats and only increased by 7% when pressure was increased over the same range. In contrast, there was no difference in the fall in RBF in SS versus MMP9 KO rats when pressure was reduced from 110 to 50 mmHg. These findings suggest that knockout of MMP9 in SS rats restores autoregulation of RBF and opposes the development of hypertension, proteinuria, glomerular injury and renal interstitial fibrosis.
Abstract 128: Visit-to-visit Variability of Systolic BP and Renal Outcomes in the SPRINT Trial
Authors: Goldman Jesse , Aggarwal Sandeep , Boyle Suzanne , Mcclure Leslie , Seshasai Rebecca , Harhay Meera
Published: July 2021

Increased visit-to-visit variability (VVV) in systolic blood pressure is a known predictor of adverse CV events & in diabetics, is associated with higher risk of incident albuminuria & chronic kidney disease. However, the impact of VVV in SBP on renal outcomes in the absence of diabetes is unknown. We investigated the association between VVV in SBP & adverse CVE & renal events among non-diabetic participants in SPRINT cohort.

Methods:
Primary exposure was quartile of within-person standard deviation of systolic blood pressure (SDBP). Primary outcomes 1) primary composite CV outcome from SPRINT study, 2) primary SPRINT renal outcome among those without CKD 3) incident albuminuria among those with & without CKD. We compared covariates by SDBP quartile, using ANOVA or chi-square tests. We fit incremental Cox hazards models to examine associations between SDBP & events. We performed sensitivity analyses for # visits in all models.

Results:
Among 9361 participants, 8589 (92%) met inclusion criteria & comprised the primary analytic sample. The mean SBP across all quartiles was similar (137 - 141 mmHg). There was no association between quartile of SDBP and the primary composite cardiovascular outcome. There was a significant association between quartile of SDBP and incident CKD among those without baseline CKD. Among 3350 participants without baseline CKD and 942 participants with CKD, higher VVV in SBP was independently associated with increased risk of incident albuminuria, regardless of baseline CKD status. This association was robust after adjustment for the number of visits. The interaction between SDBP and the primary intervention was not statistically significant in the no CKD (p=0.11) or CKD groups (p=0.93).

Discussion:
In this post-hoc analysis of SPRINT, we found that higher VVV in SBP is associated with greater risk of incident albuminuria among non-diabetic adults with and without baseline CKD. This association remained significant after adjustment for numerous potential confounders across follow-up. Our analysis demonstrates a significant association between VVV of SBP and incident albuminuria in patients with and without baseline CKD. This novel finding in an exclusively non-diabetic, hypertensive population deserves further investigation.
Abstract P198: Combination of Undaria Pinnatifida Sporophyll and Vinegar Remarkably Decreases Blood Pressure in 2-kidney, 1-clip Renovascular Hypertensive Rats
Authors: Maruyama Saki , Segawa Yukiko , Saito Natsumi , Yamaoka Ayuna , Hashimoto Hiroko , Osera Tomoko , Kurihara Nobutaka
Published: July 2021

Objective:
One of foods necessary to Japanese cuisine “Washoku” is algae, including Saccharina japonica (SJ) and Undaria pinnatifida (UP). The intake of SJ was observed to decrease blood pressure (BP) in spontaneously hypertensive rats in some studies, and in 2-kidney, 1-clip hypertensive (2K1C) rats in our studies. Furthermore, we observed the interactive effects of SJ and vinegar on BP in 2K1C rats (Kitamura S et al; Hypertension 2013, Maruyama S et al; Hypertension 2016). In the present study, we investigated the interactive effects of UP sporophyll (UPS) and vinegar, as well as the effect of UPS, on BP in 2K1C rats. We also evaluated angiotensin II type 1 receptor (AT1R) mRNA expression, in the mechanism.

Methods:
Male Sprague-Dawley rats (6 wks) were treated with sham operation (SHAM) or clipping the left renal artery (2K1C). After surgery, the rats started receiving a control diet (C) or a diet with 5.0% (w/w) UPS, and a tap water or a water containing 5.0% (v/v) rice vinegar (V) for 6 weeks. Systolic BP (SBP) was measured by a tail-cuff method every week. At the end of the protocol, mean arterial pressure (MAP) was measured in each rat under anesthesia. Then, the aortas were removed for extracting mRNA. AT1R mRNA expression was evaluated using real-time RT-PCR.

Results:
Through the experiment period, SBP was significantly higher in 2K1C-C than in SHAM-C (
P
< 0.001). Neither 2K1C-V nor -UPS showed significant differences in SBP from 2K1C-C. However, 2K1C-UPS+V provided a significant reduction in SBP compared with 2K1C-C, -V, and -UPS (
P
< 0.01). At the end of the protocol, 2K1C-C was higher in SBP than SHAM-C (166 ± 3 vs 137 ± 3 mmHg,
P
< 0.001). 2K1C-UPS+V (155 ± 4 mmHg) was tended to be lower than 2K1C-C, -V (162 ± 8 mmHg), and -UPS (164 ± 3 mmHg). Thus, BP was reduced only in 2K1C-UPS+V in 2K1C animals. The observations in MAP were similar to in the SBP. No significant differences in AT1R mRNA expression were observed among SHAM-C (1.3 ± 0.2), 2K1C-C (1.2 ± 0.3), -V (1.0 ± 0.2), -UPS (1.3 ± 0.2) and -UPS+V (1.0 ± 0.2).

Conclusion:
UPS and vinegar may decrease BP collaboratively in 2K1C rats. AT1R mRNA may not play an important role in the mechanism.