bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P419: Klotho Ameliorate Medullary Fibrosis and Pressure Natriuresis in Hypertensive Rat Kidneys
Authors: Takenaka Tsuneo , Kobori Hirofumi , Inoue Tsutomu , Miyazaki Takashi , Suzuki Hiromichi , Nishiyama Akira , Ishii Naohiro , Hayashi Matsuhiko
Published: March 2022

Recent data indicate that klotho interacts with the renin-angiotensin system (RAS). However, the effects of klotho protein supplementation on hypertensive renal injury have not been examined yet. First, the in vivo experiments were performed using spontaneously hypertensive rats (SHR). To elucidate in vivo observations, the in vitro studies were carried out to examine the interactions between klotho protein and angiotensin type-1 (AT1) receptor with immunoprecipitation and cell culture (HK-2 cell) methods. Uninephrectomized SHRs were treated with exogenous klotho protein or vehicle. Exogenous klotho protein supplementation to uninephrectomized SHRs decreased blood pressure, renal angiotensin II levels, angiotensinogen expression, HIF-1α abundance, and medullary fibronectin with increased renal klotho expression and serum and urine klotho levels. Klotho supplementation also reduced kidney weight, renal phosphorylated Akt and mTOR abundance. Furthermore, klotho supplementation restored renal autoregulation of glomerular filtration rate and renal plasma flow, and improved pressure-induced natriuresis in SHR. Klotho protein bound to AT1 receptors without affecting the bindings of angiotensin II to AT1 receptor. Klotho decreased the presence of AT1 receptors on HK-2 cells, attenuating inositol triphosphate generation. Angiotensin II elevated angiotensinogen expression in HK-2 cells, and klotho protein suppressed angiotensin II-induced increases in angiotensinogen expression. Of note, although angiotensin II improves glomerular autoregulatory ability especially at lower pressure range, angiotensin II impairs pressure-induced natriuresis. Collectively, the present data demonstrate that klotho binds with the AT1 receptors to suppress angiotensin signal transduction and inactivate the renal RAS. In addition, our results suggest that exogenous klotho supplementation suppresses Akt-mTOR signaling to decline renal hypertrophy and restores renal autoregulatory ability in uninephrectomized SHRs. Finally, the present findings implicate that klotho supplementation inhibits HIF-1α pathway to suppress medullary fibrosis, presumably involved in improvements of pressure-natriuresis and reduction in blood pressure.
Abstract P420: Sexual Difference of Tubular Renin Angiotensin System (RAS) in 2 Kidney 1 Clip Rats
Authors: Moon Ju Young , Kim Yang Gyun , Ihm Chun-Gyoo , Lee Tae Won , Jeong Kyung Hwan , Lee Yu Ho , Kim Kipyo , Sohn Il Suk , Park Seon Hwa , Kim Dong Jin
Published: March 2022

Background:
Premenopausal female manifests lower blood pressure compared with age-matched male. Intrarenal RAS is thought to be an important role in hypertension and hypertensive renal disease, while there is rare information about sexual difference in intrarenal RAS. This study was performed to evaluate sexual difference of tubular RAS in 2 kidney 1 clip(2K1C) rat model.

Methods:
A 2.5-mm clip was inserted into the left renal artery of male and female Spargue-Dawley rats and they were euthanized at 5 week following the operation. Systolic blood pressure(SBP) was measured via the tail-cuff method at 10 day interval. Medullary area for tubular RAS and cardiac tissue was collected for analysis of local RAS expression.

Results:
At 30 days after clipping operation, SBP and albuminuria was significantly increased in 2K1C male rats (SBP: male 176.75±5.58 vs. female 106.71±8.68 mmHg, p 0.004, albumin/Cr ratio: male 116.93±33.96 vs. female 56.40±13.94 mg/g, p 0.029). Also, left ventricular hypertrophy was observed only in male rats, however cardiac ACE2 and MasR mRNA did not show sexual difference. The clipped kidney(CK) of 2K1C male rat presented worse glomerulosclerosis and more macrophage infiltration. Renin mRNA was more expressed in female CK, but protein expression was rather decreased in female CK and non-clipped kidney(NCK). 2K1C female rats exhibited highly augmented ACE2 and Mas receptor(MasR) in mRNA and protein, but ACE was augmented in mRNA and reduced in protein. Immunohistochemistry showed that tubular renin and ACE was increased in 2K1C male rats, in contrast ACE2 and MasR were increased in 2K1C female rats. Medullary angiotensin II(AngII) was significantly lower in male CK, but angiotensin 1-7(Ang1-7) was higher in female CK but did not show significance (CK AngII: male 201.88±10.40 vs. female 137.01±19.33 fg/mg p 0.030, CK Ang1-7: male 22.21±4.51 vs. female 57.93±19.59 fg/mg p 0.190).

Conclusions:
Same insult of renal artery stenosis aroused different clinical outcome in 2K1C male and female. Differently activated tubular RAS might influence difference in clinical manifestation. Superiority of nonclassic tubular RAS in female rats could limit the adverse effect of classic RAS under renovascular hypertension.
Abstract P421: The Effects of Dual Angiotensin Receptor and Neprilysin Inhibitor on Organoprotection in Experimental Model of Chronic Heart Failure
Authors: Kopkan Libor , Hosková Lenka , Melenovský Vojtech , Husková Zuzana , Cervenka Ludek
Published: March 2022

The cardiac effects of dual angiotensin receptor and neprilysin inhibitor (LCZ696) as a novel therapeutic approach for inhibition of renin-angiotensin system was assessed in volume overload-induced chronic heart failure (CHF) in hypertensive Ren2 transgenic rats (TGR) with aorto-caval fistula (ACF) and compared with valsartan (VAL). CHF model was induced by ACF in male TGR at 8 weeks of age. After 5 weeks of ACF induction, LCZ696 was administered in standard dosing at 68 mg/kg/day and VAL at 31 mg/kg/day for next 15 weeks to assess the effect on mortality. In second series, 12 weeks after ACF, the animals were anaesthetized and echocardiography was performed using a 7.5 MHz probe (Vivid 7, GE) to determine left ventricular internal dimensions (LVIDd), fractional shortening (FS) and stroke volume (SV). Animals were euthanized to determine heart weight and left ventricular mass (LVm). Untreated ACF group displayed 100 % mortality till 17 weeks after ACF induction. On the other hand, LCZ696-treated ACF TGR exhibited only 12 % mortality at the end of experiment. Valsartan also markedly reduce mortality in these animals to 21 %. In comparison to intact animals, ACF significantly increased LVIDd (10,2 ± 1,1 vs. 7,6 ± 0,4 mm). Only LCZ significantly lowered LVIDd in ACF TGR (8,2 ± 0,7 mm). We also observed significantly altered ventricular function in ACF group compared to intact TGR: FS 37 ± 5 vs. 53 ± 4 % and SV 763 ± 124 vs. 395 ± 36 ml/beat. There was a significant improvement of the left ventricular function in both treated groups, where FS was increased in ACF LCZ (52 ± 4 %) or in ACF VAL (47 ± 3 %) and SV significantly decreased in LCZ (509 ± 62 ml/beat) and ACF VAL (591 ± 78 ml/beat). Compared to untreated ACF group, the LVm was significantly reduced in ACF LCZ (1958 ± 97 vs. 1697 ± 69 mg). We did not observe any adverse effect during the treatments with VAL or LCZ confirming the safety of these drugs in this model. LCZ696 treatment resulted in significant reverse left ventricular remodeling. However, we did not observe any additional effects of treatment on cardiac function with LCZ696 compared to VAL in short term follow-up. Prolonged treatment period is advised to verify possible cardioprotective benefits of LCZ696 in this model.
Abstract P424: Assessment of the RAAS-status Using Triple-A-Testing: Combining Molecular Profiling of Hypertension With Advanced Screening for Primary Aldosteronism in a Single Blood Test
Authors: Domenig Oliver , Schwager Cornelia , van Oyen Dunja , Leitner Martin , Ziegelmayer Claudia , Fabsich Christian , Poglitsch Marko
Published: March 2022

Triple-A testing is a novel mass spectrometry based approach providing a comprehensive biochemical evaluation of the circulating renin-angiotensin-system (RAS) on the basis of equilibrium angiotensin levels and circulating aldosterone levels. In contrast to previous technologies involving complex sampling procedures, RAS-Equilibrium-Analysis combines the robustness and accuracy of LC-MS/MS based quantification with the versatility of serum sampling to generate a highly accurate readout containing multiple layers of information regarding the biochemical features of the circulating RAAS. Equilibrium Angiotensin I (Ang I), Angiotensin II (Ang II) and Aldosterone were simultaneously quantified in 500μl of standard collected serum samples from healthy volunteers or hypertensive patients receiving different anti-hypertensive first-line therapies. Stable-isotope labeled internal standards were used to control for analyte recovery. Following analyte extraction, samples were subjected to UPLC-MS/MS analysis and diagnostic ratios were calculated. ACE inhibitor therapy resulted in a significant reduction of the Ang II-to-Ang I-Ratio in equilibrium analysis, which was accompanied by an up-regulation of renin, as expected. Surprisingly, PRA showed a high correlation with the sum of equilibrium Ang I and Ang II, which was independent of ACE inhibitor treatment. While the ARR was strongly suppressed in the presence of ACE inhibitor treatment, the Aldosterone-to-Angiotensin II-Ratio (AA2-Ratio) was not affected, suggesting superior applicability in screening for primary aldosteronism (PA). Triple-A testing is a mass spectrometry based multiplex assay combining Ang I, Ang II and Aldosterone to diagnostic values that draw a comprehensive picture of a patient’s "RAAS Status" . While the sum of Ang I and Ang II serves as a strong PRA surrogate marker, ACE activity and ACE inhibitor therapy efficacy can be monitored using the Ang II/Ang I-Ratio. On top, the AA2-Ratio serves as an advanced diagnostic marker for PA that might pave the way for patient screening without the need of withdrawing anti-hypertensive therapies.
Abstract P426: Suppression of Intrarenal Ras With a 20-hydroxyeicosatetraenoic Acid Antagonist Attenuates Ang II-dependent Malignant Hypertension and Reverses Established Ang-II-dependent Hypertension in Cyp1a1-ren-2 Transgenic Rats
Authors: Sedlakova Lenka , Kopkan Libor , Huskova Zuzana , Kikerlova Sona , Certikova-Chabova Vera , Falck John , Sadowski Janusz , Cervenka Ludek
Published: March 2022

Rationale and Objective:
Interplay of 20-HETE and ANG II might be a factor in pathophysiology of many forms of experimental hypertension. We hypothesized that intrarenal 20-HETE potentiates prohypertensive actions of ANG II in Cyp1a1-Ren-2 transgenic rats (TGR), a model of ANG II-dependent malignant hypertension. Therefore, we evaluated the antihypertensive effectiveness of a new, orally active 20-HETE antagonist (SOLA) in this model.

Methods:
Treatment with SOLA (10 mg.kg
-1
.day
-
1
in drinking water) was started either simultaneously with induction of hypertension (early treatment) by indol-3-carbinol or 10 days later, during established hypertension (late treatment). Systolic blood pressure (SBP, measured by radiotelemetry) was monitored continuously and indices of renal and cardiac injury, and kidney 20-HETE and ANG II levels were determined at the end of experiments.

Results:
In TGR with induced hypertension, early SOLA treatment reduced SBP elevation (to 161±3 vs. 199±3 mmHg in induced TGR, p<0.001), reduced albuminuria (16±2 vs. 35±3 mg/24 h, p<0.002), glomerulosclerosis index (0.12±0.01 vs. 0.32±0.02, p<0.001) and cardiac hypertrophy (left ventricle weight (mg)/tibial length ratio: 16.9±0.4 vs 20.6±0.5, p<0.02). TGR with induced hypertension exhibited elevated intrarenal 20-HETE levels (15.2±0.03 vs. 9.2±0.02 μg/g in noninduced rats, p<0.01); however, the elevation was not altered by SOLA treatment. Hypertensive TGR showed also augmented kidney ANG II levels (405±30 vs. 51±2 fmol/g in noninduced rats, p<0.001). SOLA treatment significantly lowered kidney ANG II (95±19). Remarkably, in TGR with established hypertension, late SOLA treatment also decreased SBP (from 187±4 to 158±4 mmHg, p<0.002) and exhibited cardio- and renoprotective effects in addition to a marked suppression of kidney ANG II levels (72±12 fmol/g).

Conclusion:
In hypertensive TGR the new orally active 20-HETE antagonist attenuated the development and largely reversed the established ANG II-dependent experimental malignant hypertension, likely via suppression of intrarenal ANG II levels. This suggests that intrarenal RAS activation by 20-HETE is important in pathophysiology of this hypertension form
Abstract P427: Inhibition of the Regulator of G Protein Signaling 14, a Novel Anti-Hypertensive Mechanism
Authors: Zhang Jie , Guers John J , Oydanich Marko , Vatner Dorothy E , Vatner Stephen F
Published: March 2022

The Regulator of G Protein Signaling 14 (RGS14) knockout (KO) mouse is unique in that it not only extends longevity, but also enhances several aspects of healthful aging. The RGS14 KO mouse, compared with wild type (WT), is protected against obesity and diabetes, and has increased exercise capacity, similar to levels achieved with chronic exercise training, all potentially important anti-hypertensive mechanisms. The goal of this investigation was to test more directly that the RGS14 KO mouse is protected against hypertension. Accordingly, we chronically infused angiotensin II (1.44 mg/kg/day) by implanted osmotic pump for 14 days. Stroke volume was measured by cardiac echocardiography. Cardiac output was calculated as the product of stroke volume and heart rate. Heart rates were not different in WT and RGS14 KO prior to angiotensin II infusion or after infusion (425±11 beats/min in WT vs. 420±13 beats/min in KO). Prior to angiotensin II baseline values for mean arterial pressure were similar in WT (84±3 mmHg) and RGS14 KO (79±2 mmHg) and baseline values for systemic vascular resistance, calculated as mean arterial pressure/cardiac output, were also similar in WT (3.7±0.1 mmHg/mL/min) and RGS14 KO (2.2±0.2 mmHg/mL/min) before angiotensin II infusion. As expected, the angiotensin infusion for 14 days increased mean arterial pressure by 69±8 % and systemic vascular resistance by 43±9 % in WT. Surprisingly, angiotensin II failed to increase either mean arterial blood pressure or systemic vascular resistance significantly in RGS14 KO mice. Thus the increases in arterial pressure and vasoconstriction, pathognomonic of angiotensin II, were completely blocked in the RGS14 KO mouse, implicating this mechanism as a potential novel therapeutic modality for treating hypertension.
Abstract P428: Internalization of Angiotensinogen is Coupled to Oxidative Stress in Human Retinal Epithelial Cells
Authors: Pulgar Victor M , Cruz-Diaz Nildris , Westwood Brian M , Chappell Mark C
Published: March 2022

We previously reported that isolated proximal tubules internalize angiotensinogen (Aogen); labeled Aogen accumulated in the nuclear and mitochondrial fractions and was associated with increased oxidative stress. Aogen internalization in non-renal epithelial cell types is unknown, thus, we assessed Aogen uptake in human retinal ARP-19 cells. Cells, maintained in serum-free media to remove extracellular sources of Aogen and renin were exposed to 125I-Aogen at 37°C and washed in HCl-glycine to dissociate any membrane-bound label. Subcellular fractionation revealed that the majority of the labeled Aogen localized to the nucleus with a lower accumulation in the mitochondrial and cytosolic fractions [42.0 ± 0.2% vs. 12.0 ± 0.2% and 5.2 ± 0.2%, respectively, p<0.01; n=3]. The rate of Aogen internalization in the retinal cells was 244 ± 15 fmol/hr/mg [n=3]; however, the cellular uptake of 125I-labeled Ang II, Ang I or Ang 7 was not evident [< 1 fmol/hr/mg]. Cells were then exposed to a low concentration of Aogen [200 pM] for 60 mins and oxidative stress assessed. As shown in the figure, Aogen elicited a marked increase in oxidative stress
[*P<0.01 vs. control(CON); n=4-5 all groups]
that was abolished by Apocynin (APO). Atorvastatin (ATV) also blocked the Aogen response, but did not attenuate Aogen uptake. Ang II (AII, 200 pM) had no effect and the AT1R antagonist losartan (LOS, 10 μM) failed to block Aogen uptake or its response. Finally, the dynamin inhibitor dynasore (DYN) blocked internalization and abolished the Aogen response. We conclude that human retinal cells internalize Aogen through a pathway distinct from the Ang II-AT1R axis to elicit an acute increase in oxidative stress.
Abstract P430: Soluble Epoxide Hydrolase Inhibition Augments Ras Blockade Renoprotection in 5/6 Nephrectomized Ren-2 Transgenic Hypertensive Rats With Chronic Kidney Disease
Authors: Certikova-Chabova Vera , Kujal Petr , Skaroupkova Petra , Vanourkova Zdenka , Kopkan Libor , Huskova Zuzana , Sedlakova Lenka , Sadowski Janusz , Kompanowska-Jezierska Elzbieta , Hwang Sung H , Hammock Bruce , Imig John , Cervenka Ludek
Published: March 2022

Rationale and Objective:
We showed recently that increasing kidney tissue epoxyeicosatrienoic acids (EETs) by blocking soluble epoxide hydrolase (sEH) and thereby blocking EETs degradation to inactive dihydroxyeicosatrienoic acids (DHETEs) substantially attenuated the progression of chronic kidney disease (CKD) in Ren-2 transgenic hypertensive rats (TGR) subjected to 5/6 renal mass reduction (5/6 NX). In this study we examined if in this model addition of sEH inhibition to the complex (dual) renin-angiotensin system (RAS) blockade would bring additional renoprotective effects in already established CKD.

Methods:
TGR aged 9 weeks underwent 5/6 NX and then were left untreated for 6 weeks to develop CKD. Then dual RAS blockade : ACE inhibition (trandolapril) + angiotensin AT
1
receptor blockade (losartan) was instituted, alone or combined with sEH inhibition (c-AUCB, 3 mg/l in drinking water). During the 60 weeks’ follow-up period albuminuria and urinary creatinine excretion was repeatedly determined. The following experimental groups were investigated: ; 1) sham-operated TGR; 2) Untreated 5/6 NX TGR; 3) 5/6 NX TGR + RAS blockade ; 4) 5/6 NX TGR + RAS + sEH blockade. Sham-operated transgene-negative normotensive Hannover-Sprague Dawley (HanSD) rats served as basic controls. In separate groups renal glomerular and tubulointerstitial injury was assessed, and effects of two weeks’ treatments on systolic blood pressure (SBP, measured by telemetry) and on kidney ANG II, ANG 1-7, EETs and DHETEs levels were determined.

Results:
All untreated TGR died by week 14 after 5/6 NX. RAS blockade increased the final survival rate to 23%, normalized SBP (116 ± 3 vs. 198 ± 3 mmHg, p<0.0015), reduced albuminuria (46 ± 5 vs. 102 ± 12 mg/24 h, p<0.001) and intrarenal ANG II (27 ± 8 vs. 189 ± 14 fmol/g p<0.0015) and did not alter kidney EETs/DHETEs ratio. After addition of sEH blockade kidney EETs/DHETEs ratio increased to 2.89 ± 0.42 (p<0.001 vs. 5/6 NX TGR treated with RAS blockade), the final survival rate increased to 42% and indices of renal glomerular and tubulointerstial injury improved.

Conclusion:
Addition of sEH blockade to the RAS blockade brings additional renoprotective effects on the CKD progression in 5/6 NX TGR, even when applied in the advanced phase of the disease.
Abstract P432: The Effect of Carbonyl Stress on Renal Injury Induced by Renal Congestion
Authors: Ohsaki Yusuke , Takahashi Chika , Mori Takefumi , Ito Sadayoshi
Published: March 2022

Background:
Due to the functional linkage between cardiac function and renal function, a decline in renal function exacerbates cardiac function and a decline in cardiac function exacerbates renal function. Renal congestion is reported to contribute to the decline of renal function in heart failure patients. Regarding the mechanism of kidney failure caused by congestion, although it is suggested that ischemia is involved due to an increase in venous pressure and a decrease in blood flow, it has not been sufficiently elucidated. Since overexpression of glyoxylose-1 (GLO1), a methylglyoxal (MG) metabolizing enzyme, which is a type of carbonyl stress, has been reported to attenuate impairment due to renal ischemia reperfusion (I/R). In this study, we aimed to investigate the effect of carbonyl stress on kidney damage due to renal congestion using GLO1 overexpressing rats.

Methods:
Male Wistar wild type (WT) rat and GLO1 transgenic (GLO1) rat were used for experiment. Left kidney was congested by placing silver clip on left renal vein under anesthesia. Two weeks after surgery, renal cortical and outer medullary mRNA markers of fibrosis [transforming growth factor-β (TGF-β) and fibronectin (FN)], tubular injury [osteopontin (OPN) and kidney injury molecule 1 (KIM-1)] and inflammations [monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α)] were measured. Results; Relative mRNA expression of cortical TGF-β (contralateral kidney; 1.00
+
0.09, congested kidney; 2.44
+
0.33, respectively), FN (1.00
+
0.11, 2.71
+
0.46), OPN (1.00
+
0.18, 6.41
+
1.47), KIM-1 (1.00
+
0.59, 21.20
+
6.31), MCP-1 (1.00
+
0.24, 2.93
+
0.56) and TNF-α (1.00
+
0.14, 1.62
+
0.18) were significantly increased in congested kidney compared to contralateral kidney. Relative mRNA expression of cortical TGF-β (GLO1tg; 1.69
+
0.20, WT; 2.44
+
0.33, respectively), FN (1.53
+
0.33, 2.71
+
0.46), TNF-α (1.00
+
0.14, 1.62
+
0.18) in GLO1tg rat were significantly decreased compared to WT rat. No significant change was observed between renal medullary area of WT rat and GLO1tg rat.

Conclusion:
Renal congestion induces renal fibrosis, tubular injury and inflammation, and carbonyl stress which could contribute to the pathophysiological mechanism on renal injury in cardiac failure.
Abstract P440: Renin-angiotensin Signal Develops Arterial Senescence and Atherosclerosis via Modulation of Mitochondrial Dynamics
Authors: Ikeda Yoshiyuki , Iwabayashi Masaaki , Sasaki Yuichi , Akasaki Yuichi , Higuchi Koji , Miyata Masaaki , Ohishi Mitsuru
Published: March 2022

Introduction:
Mitochondria are dynamic organelles that undergo fusion and fission. It is reported that renin-angiotensin signal (RAS) inhibition retards arterial senescence and development of arteriosclerosis. This study aims to clarify whether mitochondrial dynamics is involved in the effects of RAS-inhibition on arterial senescence and atherosclerosis.

Methods and Results:
Vascular smooth muscle cells (VSMC) were used in in vitro experiments. Administration of Angiotensin II to VSMCs increased p53 and p21 protein expressions and senescence associated beta galactosidase (SA-beta Gal) positive cells, indicating that angiotensin II induces cellular senescence. Administration of oxidized low-density lipoprotein (ox-LDL) to VSMC also facilitated cellular senescence through RAS stimulation. Dynamin-related protein 1 (Drp1), which mediates mitochondrial fission, was activated with phosphorylation at serine 616 and mitochondrial fission assessed by electron microscopy increased in VSMC with either angiotensin II or ox-LDL administration. Administration of pharmacological Drp1 inhibitor, mdivi1, to VSMC with either angiotensin II or ox-LDL stimulation decreased mitochondrial fission, increased fused mitochondria and retarded cellular senescence. These results suggest that mitochondrial fission is crucial to develop stress induced cellular senescence. We also conducted in vivo experiments using C57BL6, apolipoprotein E knockout (ApoE KO) and double KO mice (DKO) of angiotensin II type Ia receptor KO and ApoE KO. Ser616p-Drp1 and mitochondrial fission increased in the artery of ApoE KO compared to age-matched C57BL6. The degree of arterial senescence and atherosclerosis are greater in ApoE KO than in C57BL6 assessed by SA-beta Gal and oil red o staining and immunoblot of p53 and p21. ATP production was lower and reactive oxygen species (ROS) production was higher in ApoE KO. DKO showed lower degrees of arterial senescence, ROS generation and atherosclerosis compared to AopE KO. Expression of arterial Ser616 p-Drp1 was lower and the number of fused mitochondria and ATP production were higher in DKO than ApoE KO.

Conclusion:
Mitochondrial fusion plays a crucial role to retard arterial senescence and atherosclerosis by RAS-inhibition.
Abstract P441: Accelerated Age-dependent Cardiovascular and Cognitive Decline in Dahl-S Rats is Associated with Elevated Levels of an Endogenous Na/K-ATPase Inhibitor
Authors: Fedorova Olga V , Grigorova Yulia N , Long Jeffrey M , McPherson Rebecca L , Juhasz Ondrej , Wei Wen , Zernetkina Valentina , Petrashevskaya Natalia , Fishbein Kenneth W , Spencer Richard G , Rapp Peter R , Lakatta Edward G
Published: March 2022

Age-associated central arterial stiffening contributes to both cerebral arterial fibrosis and to cognitive impairment. Accelerated aging, accompanied by a gradual increase in blood pressure (BP) and aortic remodeling, occurs in Dahl-S rats (DSS) vs. normotensive Sprague-Dawley rats (S-D) counterparts even in the absence of a high salt intake. A novel pro-hypertensive factor marinobufagenin (MBG) is implicated in DSS hypertension. Here we determined whether an increase in MBG is also implicated in age-associated arterial remodeling in DSS.

Methods:
Life span was measured in 60 S-D and 78 DSS. BP, pulse wave velocity (PWV), behavioral water maze test, ANGII, MBG and aortic collagen were assessed in 3 and 9-mo S-D and DSS on a normal 0.5% NaCl intake.

Results:
Median life span in DSS is reduced by 50% vs. S-D (12±1 vs. 24±2 mo, p<0.01). At 3-mo DSS had higher SBP, PWV, ANGII, MBG, aortic and large cerebral arterial wall remodeling vs. 3-mo S-D (Table). Between 3 and 9-mo DSS, but not S-D, exhibited further increase in SBP, PWV, MBG and aortic collagen deposition. In a redundant place-cue version of the water maze test, 3-mo DSS demonstrated numerically impaired spatial hippocampal memory vs. 3-mo S-D, and by 9-mo, performance in DSS suggested the development of motor impairments, thus precluding an uncontaminated assessment of their spatial memory.

Conclusions:
In DSS high MBG occurred concurrently with fibrosis of aorta and large cerebral arteries and numerically impaired spatial memory. With advancing age of DSS further increase in BP, aortic stiffness and spatial learning/motor deficit occurred in context with an increase in MBG, which suggested an implication of MBG in these declines.
Abstract P443: Multiple Chronic Conditions in Older Adults: Implications for Clinical Trials & Guidelines in Hypertension
Authors: Egan Brent M , Sutherland Susan E , Rutledge Valinda , Davis Robert A , Tilkemeier Peter L , Sinopoli Angelo
Published: March 2022

Background:
Multiple chronic conditions ([M]CCs), including hypertension (HTN) and clinical CVD, increase sharply with age and account for most U.S. healthcare costs. In 2001, the Institute of Medicine recommended integrated clinical guidelines for MCC. The dearth of integrated guidelines reflects limited inclusion of complex patients in clinical trials and continued focus on individual diseases.

Methods:
To explore implications of MCC for clinical trials and HTN guidelines in older adults, hierarchical clustering was used to segregate beneficiaries in one large Medicare Shared Savings Program into clusters with similar groups of MCC. Clusters were named for the most prevalent CC and described by number of CCs, prevalent HTN, CVD, behavioral health diagnoses and paid claims.

Results:
The 50,627 beneficiaries (mean 72 yrs) segregated into 12 clusters; 36,533 (72.2%) had HTN. A total of 33,262 beneficiaries (65.7%) segregated into 6 complex clusters (CHF, CKD, Diabetes, Cancer, COPD, Vascular) with a high prevalence of CVD; 27,324 (82.1%) had HTN. The CHF and CKD clusters had the highest mean number of CCs (9.8, 7.5, respectively), HTN prevalence (94.3%, 91.9%), and yearly costs ($37,700, $26,700/beneficiary). Diabetes, cancer, COPD and vascular disease clusters also had a large burden of CCs (5.9, 5.8, 5.1, 5.4) and HTN (88.3%, 73.6%, 70.7%, 83.9%) with annual healthcare costs from $19,500 (cancer) to $12,900 (COPD); more than 1/3 of patients in the CHF, CKD, diabetes and vascular clusters had a behavioral health diagnosis, most often depression. Of 17,365 (34.3%) beneficiaries in less complex clusters, 9,209 (54%) had HTN, 90+% were candidates for primary CVD prevention, less than 10% had behavioral health diagnoses, and costs were lower.

Conclusions:
HTN impacts ~82% of older adults with a higher burden of MCC, and ~75% (27,324/36,533) of Medicare beneficiaries with HTN have a large burden of MCCs. Behavioral health diagnosis, associated with adverse outcomes and costs, are common with MCCs. Clinical care, outcomes and costs for older adults with HTN and MCCs could improve with more representative inclusion in clinical trials and translation through integrated clinical guidelines developed by multi-specialty/disciplinary teams.
Abstract P450: AT2 Receptor Stimulation Reduces Ischemic Brain Damage Through AT2 Receptor-interacting Protein Signal
Authors: Iwanami Jun , Mogi Masaki , Wang Xiao-Li , Tsukuda Kana , Higaki Akinori , Kukida Masanori , Nakaoka Hirotomo , Yamauchi Toshifumi , Bai Hui-Yu , Shan Bao-Shuai , Min Li-Juan , Horiuchi Masatsugu
Published: March 2022

Objectives:
We reported the preventive effects of angiotensin II type 2 (AT2) receptor stimulation on ischemic brain damage. Moreover, we have cloned ATIP (AT2 receptor interacting protein) as a protein interacting specifically with the C-terminal tail of the AT2 receptor, and suggest that ATIP should play key roles in diverse mechanisms of AT2 receptor actions. However, the effect of ATIP on ischemic brain damage is unclear. Therefore, we investigated the effects of the ATIP and compound 21 (C21), a selective non-peptide AT2 receptor agonist, on focal cerebral ischemia.

Method:
Ten-week-old male ATIP-transgenic (ATIP-Tg) and littermate (WT) mice were subjected to middle cerebral artery occlusion (MCAO) with silicon-coated micro-filament. C21 (10 μg/kg/day) was administered 2 weeks before MCAO. Twenty-four hours after MCAO, ischemic volume was determined and depicted as mm
3
. Expression of methyl methanesulfonate sensitive 2 (MMS2) mRNA as a neuroprotective factor was determined by real-time RT-PCR. Cerebral blood flow (CBF) before and after MCA occlusion were measured by laser speckle flowmetry. Collateral circulation was evaluated by the perfusion of India ink.

Results:
Systolic blood pressure did not differ among all groups. There was no significant difference in ischemic size without C21 treatment between two strains (WT, 80 mm
3
; ATIP-Tg, 75 mm
3
). Treatment with C21 significantly decreased ischemic size in both strains (WT, 66 mm
3
; ATIP-Tg, 50 mm
3
). Interestingly, this protective effect of C21 was more marked in ATIP-Tg compared with WT mice (WT, 16% (66 of 80); ATIP-Tg, 27% (50 of 75) reduction, respectively). MMS2 expression increased in ipsilateral hemisphere of ATIP-Tg mice compared with contralateral hemisphere. There were no significant differences in CBF of core region of ischemic area, among all groups. However, the reduction of CBF in penumbra region after MCA occlusion was attenuated in ATIP-Tg mice with C21 administration. Treatment with C21 tended to increase the cerebral collateral number before MCA occlusion in ATIP-Tg mice not in WT.

Conclusions:
These results suggested that ATIP could enhance the cerebral protective effects of AT
2
receptor stimulation at least in part due to the increase of CBF and MMS2 expression after ischemia.
Abstract P458: Assessment of Cardiovascular Risk Reduction in Adults With Metabolic Syndrome or Type 2 Diabetes Treated With Lorcaserin: A Pooled Cohort Analysis
Authors: Chatterjee Debanjana , Li Xuan , Nikonova Elena , Miller Michael
Published: March 2022

Introduction:
Obesity is a risk factor for cardiovascular disease (CVD) and even modest weight loss can contribute to its reduction. Lorcaserin, a selective 5HT
2C
receptor agonist, is indicated as an adjunct to a reduced-calorie diet and increased physical activity in adults with obesity (BMI≥30 kg/m
2
) or overweight (BMI 27-29.9 kg/m
2
and at least 1 weight-related comorbidity). Using the 2013 ACC/AHA 10-year CVD risk assessment pooled cohort equation, we examined risk change in patients with metabolic syndrome or type 2 diabetes (T2DM) undergoing treatment with lorcaserin or placebo for weight loss.

Methods:
We identified patients with metabolic syndrome or T2DM in three randomized, double-blind studies (BLOOM, BLOSSOM, BLOOM-DM) examining the efficacy and safety of lorcaserin 10 mg bid (LOR) vs. placebo (PBO) at one year of treatment. Only patients with lipid values at baseline and one year were included. Once selected, patients were further stratified by weight loss at week 12 of treatment (≥5% vs. <5%). A CVD risk score >5% was classified as high risk, and a 0.5% change in risk over one year was defined as clinically relevant. CVD risk reduction by cohorts, overall and by gender, was compared.

Results:
Overall, 43% LOR (n=449/1056) and 20% PBO (n=207/1041) patients had
>
5% weight reduction at week 12 (p<0.05). Baseline CVD risk was 5.43% and 5.14% in the LOR and PBO cohorts, respectively. At one year, PBO-corrected change in CVD risk compared to LOR treatment was -0.21% (95% CI 0.02, 0.04, p=0.03; LOR -0.55% vs -0.3% PBO) overall and -0.56% (95% CI 0.12, 0.99, p=0.012; LOR -1.08% vs PBO -0.41%) in men. CVD risk in women was <5% at baseline, with no significant change seen at one year. For 12-week responders, both LOR and PBO had a clinically relevant change in CVD risk overall (-0.81% and -0.79%) and for men (-1.71% vs -1.02%). For patients with <5% weight loss, only men in the LOR cohort showed clinically relevant CVD risk changes (-0.57% vs -0.26%, respectively).

Conclusion:
The analysis suggests that patients with overweight or obesity and metabolic syndrome/T2DM
at risk for CVD,
and treated with LOR, experienced a significant CVD risk reduction at one year vs PBO, most notably among men. LOR can effectively reduce weight, which is associated with improvements in CVD risk.
Abstract P464: Sodium Glucose Cotransporter 2 Inhibition by Canagliflozin Attenuates Intrarenal Angiotensinogen Augmentation in Type 2 Diabetes Mellitus
Authors: Woods T Cooper , Satou Ryousule , Miyata Kayoko , Katsurada Akemi , Dugas Courtney M , Lightell Daniel , Navar L Gabriel
Published: March 2022

Type 2 diabetes mellitus (T2DM) is a complex disease where hyperglycemia occurs as a result of the development of insulin resistance. T2DM leads to complications, including renal and cardiovascular injury. Renal proximal tubular angiotensinogen (AGT) is stimulated by hyperglycemia via elevated oxidative stress, and is associated with activation of the intrarenal renin-angiotensin system which contributes to development of high blood pressure and diabetic nephropathy in diabetes mellitus. Sodium glucose co-transporter 2 (SGLT2) is mainly expressed in early renal proximal tubules and is responsible for most of the glucose reabsorption by the tubules. This study tested the effects of canagliflozin (CANA), an SGLT2 inhibitor, on intrarenal AGT regulation in T2DM mice. Male New Zealand Obese mice were fed a regular fat diet (RFD, 4% fat) or a high fat diet (HFD, 40% fat) to induce diabetes. When the mice fed with HFD exhibited >350 mg/dl blood glucose levels (week 0), both RFD and HFD fed mice were treated with 10 mg/kg/day CANA or vehicle for 6 weeks by daily oral gavage. Systolic blood pressure (SBP) levels were measured by a tail cuff system and 24-hour urine samples were collected using metabolic cages. Intrarenal AGT mRNA and protein levels were determined by digital PCR and western blot analysis. CANA treatment decreased blood glucose levels in HFD mice, which remained suppressed for duration of the study. SBP in HFD groups were higher than in the RFD and RFD+CANA groups (134.7±3.6, 118.7±10.8 and 108.3±7.6 mmHg) at week 6. The elevated SBP was normalized by CANA (110.0±6.0 mmHg). The HFD group exhibited greater renal cortical AGT mRNA levels than the RFD group (3.7±0.4 vs. 7.4±1.0 copies/reaction). Likewise, intrarenal AGT mRNA expression was lower in CANA treated group (4.5±0.8 copies/reaction). Western blot analysis also showed lower AGT protein levels in CANA treated group (1.02±0.08-fold compared with RFD) than in HFD group (1.49±0.08-fold). In the HFD group, CANA treatment also suppressed elevated urinary 8-isoprostane levels, a marker of renal oxidative stress. These results demonstrate that CANA attenuates intrarenal AGT augmentation that occurs in T2DM, which may mitigate the development of diabetic nephropathy and progression of high blood pressure.
Abstract P465: Arterial Hypertension and Orthostatic Hypotension in Diabetic Patients
Authors: Gaspar Ludovit , Filipova Slavomira , Bendzala Matej , Gasparova Iveta
Published: March 2022

Introduction:
Diabetes mellitus is often associated not only with arterial hypertension. but also with orthostatic hypotension, which is one of the most clinical apparent forms of cardiovascular autonomic neuropathy.

Objective:
To retrospectively assess the association of the orthostatic hypotension (OH) with macrovascular and microvascular complications of diabetes mellitus and to determine its effect on mortality.

Design and Methods:
We retrospectively analysed 187 patients with diabetes mellitus (60 patients with type 1 and 127 patients with diabetes type 2). Patients were divided into groups according to presence or absence of OH and type of diabetes. Association of OH with macrovascular and microvascular complications was evaluated and the effect of OH on 10-year all-cause mortality was also assessed.

Results:
OH was present in 31.7 % (19 of 60) of patients with DM type 1 and 32.3 % (41 of 127) of patients with DM type 2. We found strong positive association between OH and arterial hypertension grade 3 ESH/ESC in DM1 42.1 % (8 of 19) and DM2 48.8 % (20 of 41). OH was positively associated with the prevalence of myocardial infarction in DM1 (OR=10.667) and with prevalence of stroke in DM2 (OR=3.335). There was also a strong association of OH and the prevalence of peripheral artery obliterative disease in both DM1 (OR=14.18) and DM2 (OR=3.263). Patients with both types of DM and OH had significantly higher prevalence of nephropathy (DM1 OR=8.680, DM2 OR=3.237), retinopathy (DM1 OR=8.095, DM2 OR=4.078) and peripheral neuropathy (DM1 OR=17.143, DM2 OR=7.506). Overall 10-year mortality rate was significantly higher in diabetic patients with OH, in DM1 group 31.6 % (6 of 19) and in DM2 group 31.7 % (13 of 41).

Conclusion:
Presence of orthostatic hypotension in diabetics is associated with higher prevalence of macrovascular and microvascular complications of diabetes mellitus and also with higher 10-year mortality.
Abstract P474: Comparison of the Effect of Different Calcium Channel Antagonists on Arterial Stiffness and Central Pressures in Moderate Hypertensive Patients Receiving Enalapril as First Line Treatment
Authors: Cabrera-Sole Ricardo , Turpin Lucas Caridad , Rivera Urrera Liliana , Garcia Ruiz Santiago , Aguilera Saldaña Manuel
Published: March 2022

Introduction:
ACE inhibitors reduce blood pressure (BP)satisfactorily, with enalapril (ENL) being one of the most used in daily clinical practice. However, little is known about its effects on arterial stiffness (AS) and central BP when associated with calcium-antagonists (CCA). So we studied three CCA associated with ACE inhibitors.

Objectives:
To evaluate the effects of three CCA: amlodipine (AML), nifedipine ( NFD)and barnidipine (BND) associated with ENL, on AS, central systolic and diastolic BP: (SBPc, DBPc),diastolic heart function in moderate hypertensive patients (Phta).

Material and Methods:
We studied 156 Phta males (68 ± 6 years old) who were treated by their primary care physician with ENL and AML,NFD OR BND. They were grouped into three groups: Group I: 53 Phta receiving ENL +AML, Group II: 50 Phta receiving ENL+ NFD and 53 Phta treated with ENL + BND to maintain BP under 140/90 mmHg. In all, an echocardiogram was performed to measure the Left ventricular mass index (LVMI), the E / A mitral flow index . We measured with 24-hour ABPM , AS by augmentation index (AI)and pulse wave velocity (PWV), and,central BP. The results were compared and presented in Tables I:

* =p value ≤0.05

CONCLUSIONS:
according to our data, it is preferable to use AML as a CCA,because it not only reduces BP better but also the central BP, improving AS in small and large vessels. The BND would be the other choice, since it does not present significant differences with respect to the first group. NFD , in addition to, not demonstrating superiority, also does not reduce DBPc in these Phta. Therefore, we consider that the presented data have sufficient clinical relevance to choose CCA associated with an ACE inhibitor.
Abstract P481: Key Findings From Multilevel Stakeholder Input On Awareness, Gaps And Needs Related To The Burden Of Hypertension
Authors: Venkitachalam Lakshmi , Smith Tru-Kechia
Published: March 2022

Background:
Hypertension (HTN) continues to pose a considerable challenge to the health system. Suboptimal rates of screening, awareness, treatment and control, reported at national and local levels, reflect an urgent need for a coordinated and collective approach to action.

Methods:
On May 20, 2017 (World HTN day), we convened a one-day HTN summit in response to an expressed need from stakeholders across the health system (healthcare, public health, community organizations) in the Bi-State Greater Kansas City Area. To help formulate an action plan, we administered a pre-and post-survey to document stakeholder engagement in HTN programs, their awareness of existing key initiates and resources, and perceived needs to address HTN.

Results:
Overall, 24 individuals from 16 organizations registered for the event and completed a pre-event survey - healthcare system (46%), Public health or Government organizations (17%), Community organizations (29%), Academic entity (8.3). Thirteen (54%) attendees completed the post-event survey - 29% delivered healthcare services, 57% conducted community activities, 21% were patients or caregivers. Only 32% of the attendees reported a current program on blood pressure. Less than 10% of participants reported satisfaction with the availability of regularly scheduled learning opportunities or tools for healthcare professionals or patients to improve HTN. Only 21% of participants reported monitoring of performance on metrics related to high blood pressure programs. All attendees expressed interest in continued meetings, patient engagement resources, and an in-depth exploration of the underlying factors contributing to the burden of uncontrolled HTN. Findings also reflected a significant need to improve the awareness of resources like the Missouri Million Hearts initiative and Target BP™.

Conclusion:
In spite of temporal advancements in cardiovascular medicine, there exist significant gaps in the awareness and use of resources and tools to support HTN management among stakeholders in the health system. Planned strategies include a dedicated working group to proactively identify and support coordinated, multi-stakeholder efforts to reduce the HTN burden and improve cardiovascular health in our communities.
Abstract P484: Improved Heart Rate Variability, and Symptoms of Insomnia and Stress, With Use of a Closed-loop, Allostatic Neurotechnology in Law Enforcement Officers
Authors: Tegeler Catherine L , Shaltout Hossam A , Howard Lindsay J , Schmidt Krystal D , Garlin Emillee I , Tegeler Charles H
Published: March 2022

Background:
Law enforcement officers have decreased life expectancy, attributed to work-related exposure to traumatic stress and circadian disruption. Autonomic dysregulation is reported with traumatic stress, and chronic insomnia. Closed-loop therapies with real time monitoring for modulation of biological function offer a precision-guided, patient-centric strategy for brain-based therapies. High-resolution, relational, resonance-based, electroencephalic mirroring (HIRREM®) is a noninvasive, closed-loop, allostatic, acoustic stimulation neurotechnology using software generated algorithms to identify specific brain frequencies, and translate them in real time into audible tones, to support self-optimization of brain rhythms.

Objective:
To evaluate benefits for autonomic function, and symptoms of insomnia and stress, in a relatively healthy cohort of law enforcement officers, who enrolled in an IRB-approved, open label feasibility study evaluating HIRREM for diverse neuropsychological disorders. Measures done before and after HIRREM included symptom inventories for insomnia (ISI), depression (CES-D), traumatic stress (PCL-C), anxiety (GAD-7), and perceived stress (PSS). Ten minute recordings of heart rate and blood pressure allowed analysis of baroreflex sensitivity (BRS) and heart rate variability (HRV).

Results:
7 participants (1 female), mean (SD) age 47 (4.5), received 10.7 (2.6) HIRREM sessions over 11.3 (4.6) days (7.3 in office days). Data were collected before, and 22.6 (1.8) days after HIRREM completion. Use of HIRREM was associated with significantly increased HRV measured as rMSSD [from 25.3 (7.0) to 43.1 (13.0) ms, p=0.02]. BRS measured by high frequency alpha index improved [from 11.3 (8.0) to 20.1 (11.0) ms/mmHg, p=0.03]. All symptom inventories improved significantly (p<0.05), even with the small cohort. There were no adverse events or drop outs.

Conclusion:
These pilot data provide the first report of significant autonomic cardiovascular benefits, and associated symptom improvements, with use of a closed-loop, allostatic therapy for a cohort of sworn law enforcement officers. Further studies are warranted to test the efficacy of this technology in a larger law enforcement cohort
Abstract P498: Redox Regulation of Vascular Smooth Muscle cGMP Signaling and Blood Pressure by Cytochrome B5 Reductase 3
Authors: Straub Adam C , Rahaman Mizanur , Nguyen Anh , Miller Megan , Hahn Scott , Martin Emil
Published: March 2022

Oxidized soluble guanylate cyclase (sGC) heme iron (Fe
3+
) is desensitized to nitric oxide (NO) and attenuates cGMP production needed for downstream activation of PKG-dependent signaling and vasodilation. While reactive oxygen species drive oxidation of sGC heme iron, the basic mechanism(s) governing sGC heme iron recycling to its NO-sensitive, reduced state (Fe
2+
), are unknown. Here we report cytochrome
b5
reductase 3 (Cyb5R3), also known as methemoglobin reductase, as a novel sGC heme iron reductase and regulator of cGMP production in vascular smooth muscle cells (VSMCs). Oxidant challenge studies demonstrate that VSMCs have an intrinsic ability to reduce oxidized sGC heme iron and form protein-protein complexes between Cyb5R3 and oxidized sGC. Genetic knockdown and pharmacological inhibition in VSMCs reveal Cyb5R3 expression and activity is critical for NO-stimulated cGMP production and vasodilation. Mechanistically, Cyb5R3 directly reduces oxidized sGC for NO sensitization assessed by biochemical, cellular, and
ex vivo
assays. Furthermore, generation of a smooth muscle specific Cyb5R3 knockout shows increased blood pressure and impaired endothelial dependent vasodilation. Together, these findings uncover new insights into NO-sGC-cGMP signaling and reveal Cyb5R3 as the first identified physiological sGC heme iron reductase in VSMC. The co-expression of Cyb5R3 and sGC in multiple cell types may unveil a fundamental mechanistic partnership that is critical in numerous physiological and pathophysiological processes.