bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P216: Thoracic Epidural Administration of Resiniferatoxin Improves Cardiac and Autonomic Dysfunction in Post-MI Rats
Authors: Wang Hanjun , Zucker Irving H.
Published: March 2022

Our recent study demonstrated that chronic ablation of the cardiac sympathetic afferent reflex (CSAR) at the time of myocardial infarction (MI) by destroying TRPV1-expressing CSAR afferent nerve endings by epicardial delivery of the afferent neurotoxin, resiniferatoxin (RTX) significantly improved cardiac and autonomic dysfunction post MI. In this study, we provide an alternative route of epidural peri-ganglion administration of RTX for CSAR ablation thus destroying TRPV1-expressing CSAR afferent neuronal soma at the level of the T1-T4 DRGs in post-MI rats. This strategy completely abolished the CSAR for up to 6 months, significantly longer than epicardial application (~3-4 months). We compared the cardioprotective effects of epidural application of RTX with [Sar
9
,Met(O
2
)
11
]-substance P (SSP)-saporin (SAP) to determine if SP-containing CSAR afferents ablation mimics the cardioprotective effects of RTX in post-MI rats. Echocardiographic data demonstrated that both epidural RTX and SSP-SAP treatments significantly slowed LV chamber dilation in MI rats. Epidural application of RTX significantly decreased cardiac sympathetic tone (%max: 44±5 (n=6) vs. 11±1 (n=9), vehicle vs. RTX, P<0.01) and improved baroreflex sensitivity at 12-weeks post-MI whereas SSP-SAP had less effect on autonomic dysfunction. Compared to vehicle-treated MI rats (n=16), epidural RTX (n=13) reduced left ventricular end diastolic pressure (LVEDP: 22±1 vs. 7±1 mmHg, P<0.01) whereas epidural SSP-SAP only partially reduced LVEDP (15±2 mmHg, n=10, p<0.05) in MI rats. All groups had similar infarct size. Cardiac hypertrophy and lung edema in MI rats were reduced by epidural RTX whereas they were only partially reduced by SSP-SAP. Pressure-volume analysis data showed that epidural RTX significantly improved cardiac diastolic dysfunction in MI rats to a greater extent than SSP-SAP, neither of which improved cardiac systolic dysfunction. These data suggest that 1) epidural peri-ganglion RTX ablation of the CSAR can be used to reduce cardiac remodeling and autonomic dysfunction post-MI; 2) SP-containing thoracic afferents partially but not completely mediate the cardioprotective effects of thoracic afferent ablation post MI.
Abstract P217: Western Diet Promotes Cardiac Diastolic Dysfunction by Increasing Cardiomyocytes Calcium Sensing Receptor via Activation of Parathyroid Hormone, Parathyroid Related Hormone and Their Receptor- 1 in Female Mice
Authors: Habibi Javad , Jia Guanghong , Aroor Annayya , DeMarco Vincent , Garro Mona , Dodd Brittany , Niles Brett , Sowers James
Published: March 2022

Background:
Data from our Lab and others indicate that consumption of a western diet (WD), high in fat and refined carbohydrates promotes cardiac hypertrophy and diastolic dysfunction. Recently, a role for calcium sensing receptor (CaSR) and the fibroblast growth factor 23 (FGF 23)/ Klotho axis has been increasingly recognized in the pathogenesis of cardiac hypertrophy and diastolic dysfunction. However, the role of these factors in WD induced cardiac dysfunction has not been elucidated. Therefore, the purpose of this study was to determine mechanisms and signaling pathways underlying WD-induced cardiac diastolic dysfunction in female C57-Bl6/J mice.

Methods and Results:
Four week-old female C57-BL6/J mice were fed a control diet (CD) or WD containing fat (46%) and fructose (17.5%) for 16 weeks. Then, left ventricular (LV) and serum were harvested and processed for immunohistochemistry and serum analysis. Four μm paraffin embedded sections of the LV were incubated with primary antibodies (CaSR), parathyroid hormone (PTH), parathyroid related hormone (PTHrP), parathyroid hormone receptor-1 (PHTR-1), parathyroid hormone receptor-2 (PHTR-2), (FGF23), klotho and appropriate secondary antibodies. Images were captured with a bi-photon confocal microscope and signal intensities were quantified as gray scale intensities. Analysis of immunofluorescence images revealed that consumption of a WD resulted in significantly higher expression level of CaSR, PTH, PTHrP, PTHR-1 and FGF23. Also, consumption of WD significantly increased the serum PTH level. Furthermore, analysis of WGA stained images showed significant hypertrophy of LV cardiomyocytes. Interestingly, WD did not increase the expression of PTHR-2 and Klotho in LV but levels of this protein in the coronary arteries.

Conclusion:
These findings support the preliminary notion that there is a role of PTH, PTHR-1 and PTHrP signaling in dietary promotion of cardiomyocytes hypertrophy and diastolic dysfunction. These effects could be mediated via modulation of cardiac calcium metabolism.
Abstract P230: Glucagon-like Peptide-1-induced Increases in Afferent Renal Nerve Activity and Renal Sodium Excretion: Role of Trpv1
Authors: Zhong Beihua , Wang Donna
Published: March 2022

Glucagon-like peptide 1 (GLP-1), an incretin hormone that has clinically been used to treat type 2 diabetic patients, may cause diuresis and natriuresis. However, the mechanism of GLP-1 effects on the kidney is largely unknown. We test the hypothesis that GLP-1 increases afferent renal nerve activity (ARNA) and renal sodium excretion by activation of the transient receptor potential vanilloid 1 (TRPV1) channels expressed in afferent renal nerves innervating the kidney. Exendin-4 (Ex4, 3*10-7M), a GLP-1 receptor agonist perfused into the left renal pelvis, increased ipsilateral ARNA in wild type (WT) mice when compared to TRPV1-null mutant (TRPV1–/–) mice (ARNA % integrated activity, WT:160±22 vs TRPV1-/-: 109±5, p<0.05). Ex4-induced increases in ARNA in WT mice were abolished by capsazepine, a selective antagonist of TRPV1, or by RP67580, a selective antagonist of the neurokinin 1 (NK1) receptor, but not by calcitonin-gene related peptide (CGRP)8-37, a selective antagonist of the CGRP receptor pre-perfused into the renal pelvis. Ex4 increased substance P (SP) and CGRP release from the renal pelvis isolated from WT but not TRPV1-/- mice. Ex4-induced increases in SP and CGRP in WT mice were prevented by Ex9-39, a GLP-1 receptor antagonist, 2,5-dideoxyadenosine, an adenylate cyclase inhibitor (ACI), and brefeldin A (BFA), an EPAC inhibitor, or attenuated by bisindolylmaleimide I (BIM) , a PKC inhibitor, and H89, a PKA inhibitor. Wortmannin (Wort), a PI3K inhibitor, had no effect on Ex4-induced SP or CGRP release. Acute Ex4 treatment (3ug/kg, i.p.) increased renal sodium excretion in both strains with greater degree of increases in WT compared to TRPV1-/- mice (increased % rate, WT: 160±36 vs. TRPV1-/-: 82±7, p<0.05). Thus, our data show that Ex4 increases ARNA, renal SP and CGRP release, and urinary sodium excretion in WT mice, and these functions of Ex4 are impaired in TRPV1-/- mice. These data indicate that Ex4-induced enhancement of ARNA and natriuresis attributes to, at least in part, activation of TRPV1-positive afferent nerves possibly via stimulating the GLP-1R/cAMP-PKA/PKC-TRPV1/SP pathway.
Abstract P231: High Fat Diet-induced Er Stress and Inflammation in the Kidney: Role of Trpv1-positive Afferent Renal Nerves
Authors: Yu Shuang-Quan , Wang Donna
Published: March 2022

Chronic high fat diet (HFD) intake may lead to enhancement in endoplasmic reticulum (ER) stress, reactive oxygen species (ROS) production, and inflammation in the kidney, but the mechanisms of HD effects are largely unknown. This study tests the hypothesis that HFD impairs afferent renal nerves expressing the transient receptor potential vanilloid 1 (TRPV1) channels, and that stimulating/preserving TRPV1-positive afferent renal nerves prevents against HFD-induced increases in ER stress, ROS production, and inflammation in the kidney. HFD decreased levels of TRPV1 in the kidney, levels of urinary calcitonin-gene related peptide (CGRP) and substance P (SP), and responses of afferent renal nerve activity (ARNA) to capsaicin, a TRPV1 agonist, perfused into the renal pelvis. HFD increased ER stress (XBP-1, CREB2, GRP78, p-JNK), ROS production (urinary 8-isoprostane), and inflammation (TNF-α, IL-1β) in the kidney. N-oleoyldopamine (OLDA, a TRPV1 agonist, 1 ng/kg, daily) or vehicle was given intrathecally (i.t.) via indwelled catheters to segments (T8-L3) supplying the kidneys of rats fed a HFD or normal fat diet (Con) for 8 weeks. OLDA prevented HFD-induced decreases in the levels of renal TRPV1, urinary CGRP and SP, and ARNA responses to capsaicin, as well as HFD-induced increases in renal ER stress, ROS production, and inflammation. OLDA-induced protection during HFD was abolished by degeneration of TRPV1-positive afferent renal nerves by topical application of resiniferatoxin (RTX, 2 μg/ml x 2 times), a potent TRPV1 agonist, on renal nerves (TNF-α, Con: 0.17±0.02, HFD: 0.41±0.03, HFD+OLDA: 0.21±0.02, HFD+OLDA+RTX: 0.46±0.04, p<0.05; 8-isoprostane, Con: 8.8±1.2, HFD: 17±2, HFD+OLDA: 11±1, HFD+OLDA+RTX: 22±3 ng/day, p<0.05). Thus, our data show that HFD impairs TRPV1-positive afferent renal nerves, and chronic stimulation of TRPV1 via intrathecal injection of OLDA to T8-L3 segments preserves TRPV1-positive afferent renal nerves to against HFD-induced ER stress, ROS production, and inflammation in the kidney given that impairment of this population of afferent renal nerves abolishes OLDA effects. These data indicate that TRPV1-positive afferent renal nerves play a counteractive role against HFD-induced renal injury.
Abstract P240: Gender Differences in the Association of Adiponectin and BMI in a Rural Cohort of African Americans
Authors: Pointer Mildred A , Bridges Lakeesha , Wells Candace , Bolin David , Greene Natasha
Published: March 2022

Gender differences in the association of adiponectin with visceral and subcutaneous fat have been reported among African Americans (AAs). Specifically, adiponectin is negatively associated with visceral and subcutaneous fat in women but positively associated in males. The previous findings were obtained, however, under a controlled environment using expensive scanning equipment. In this study we wanted to determine if similar gender differences could be observed when sampling from a rural cohort of African Americans under less controlled conditions. African Americans (11 males; 36 females) attending a health fair at a local school were recruited and the following were measured or collected: resting blood pressure, weight, self reported height, blood sample, and spot urine. Both males and females tended to be hypertensive (SBP: 148 ± 6 in males vs 129 ± 3 mmHg in females; p=0.002; DBP: 79 ± 5 and 70 ± 2mmHg, p=0.047) and obese (35.6 ± 2 vs. 33.4 ± 1 in males and females, respectively; p=0.52). Although there was no difference in BMI between males and females, total adiponectin levels were significantly higher in males as compared to females (6.9 ± 1 vs. 3.9 ± 0.5 μg/ml; p=0.026). Interestingly, BMI was positively associated with adiponectin in males (p=0.004) but there was no significant association between BMI and adiponectin in females (p=NS). These findings are similar to what has been previously reported when sampling under controlled conditions and suggest that sampling from the field could be a viable means to further investigate the gender differences in adiponectin and adiposity in African Americans, particularly among rural residents.
Abstract P248: Changes in Dipping Pattern of Blood Pressure During the Progression of Renal Injury in Dahl Salt-sensitive Hypertensive Rats
Authors: Nishiyama Akira , Fujisawa Yoshihide , Rahman Asadur , Rahman Asadur , Nakano Daisuke , Hitomi Hirofumi , Sufiun Abu
Published: March 2022

A growing body of clinical evidence has indicated that non-dipper pattern of circadian rhythm of blood pressure (BP) is a great risk of cardiovascular disease, which is accompanied by impaired renal function and proteinuria. Here, we aimed to investigate the circadian rhythm of BP during the progression of renal injury in Dahl salt-sensitive (DSS) hypertensive rats. DSS rats were treated with a high salt diet (HS; 8% NaCl) for 10 weeks (n=10). Before starting a HS diet, the difference in mean arterial pressure (MAP) between dark and light period was 6.46±0.61 mmHg in normal salt (0.3% NaCl)-fed DSS rats. Treatment with a HS diet for 5 days did not change renal function, but blood pressure was increased. Furthermore, the difference in MAP between dark and light period was significantly increased (11.05±0.87 mmHg, P<0.05), suggesting extreme dipping type of circadian BP. However, further HS diet feeding for 10 weeks induced the development of hypertension, renal tissue injury and proteinuria, which were associated with non-dipper pattern of BP. Namely, the MAP was similar between dark and light period (180.47±6.26 vs.177.92±6.33 mmHg). After switching to normal salt diet for 4 weeks, MAP was significantly decreased and circadian rhythm of BP was returned to normal dipper type (157.27±3.96 vs. 149.93±4.11 for MAP in dark and light period, respectively). In conclusion, the present study has demonstrated that treatment with HS diet initially showed extreme dipping pattern of BP in DSS rats, whereas it changed to non-dipping pattern of BP during the progression of renal tissue injury and proteinuria. These data support the hypothesis that non-dipping pattern of BP is associated with the progression of renal injury during the development of salt-dependent hypertension, which may contribute to the cardiovascular events.
Abstract P250: Central Mechanisms Mediating Angiotensin II-Salt Hypertension in Rats
Authors: Lu Jiao , Wang Hong-Wei , Ahmad Monir , Leenen Frans H
Published: March 2022

Circulating Ang II causes persistent activation of brain angiotensinergic pathways through a neuromodulatory aldosterone (aldo)-mineralocorticoid receptors (MR)-epithelial Na
+
channel (ENaC)-ouabain pathway. The response of BP to circulating Ang II is enhanced by high salt intake. To evaluate the central mechanisms that mediate Ang II-salt induced hypertension, Wistar rats were treated with regular salt diet (0.4% NaCl), high salt diet (2% NaCl), sc Ang II (150 ng/kg
/
min), or sc Ang II with high salt diet for 14 days. In the 2
nd
exp, MR blockers (eplerenone, spironolactone), ENaC blocker (benzamil), AT
1
R blocker (losartan) or vehicles (Veh) were icv infused combined with Ang II-salt. BP was recorded by telemetry. Gene expression was assessed by real-time qPCR. Plasma Ang II and tissue aldosterone were measured by RIA. Ang II alone caused a small increase in MAP (112±1 vs 99±1 mmHg), and BP was markedly increased by Ang II-salt (152±4 mmHg, P<0.05 vs. others). BP increases to Ang II-salt were largely inhibited by central infusion of MR blockers (103±2mmHg), benzamil (100±3mmHg) or losartan (98±4mmHg). Ang II alone or together with salt decreased 11βHSD2 and MR mRNA expression but increased AT
1
R and ENaC γ mRNA expression in the PVN, and increased AT
1
R mRNA level in the RVLM. Sc Ang II or high salt diet had no effect on mRNA levels of CYP11B1, B2, ENaC α or β in the PVN or RVLM. Considering that AT
1
R mRNA expression increases in both PVN and RVLM and central MR-ENaC-AT
1
R blockade prevents the hypertension, these results suggest that activation of Ang II-AT
1
R signaling and MR-ENaC pathway in the brain contribute to both Ang II and Ang II-salt hypertension.
Abstract P252: Effect of Maternal Diabetes on Fetal Programming of Vascular Remodeling Mechanisms in Adult Rats
Authors: Dib Abdallah , Bourreau Jennifer , Loufrani Laurent , Henrion Daniel , Fassot Celine
Published: March 2022

Modifications of the intra-uterine environment are now recognized as an important cause of fetal stress. Leading to several responses such as loss of structure/function and pre-emptive adaptations to an adverse post-natal environment, and finally to adult diseases. It has been demonstrated that children of diabetic mothers have an increased risk of developing cardiovascular diseases (i.e. hypertension) during adulthood.

Blood vessels are able to reorganize their structure in response to physiological alteration of blood flow or pathological stimuli. Constrictive vascular remodeling is currently associated with the occurrence of cardiovascular diseases. Thus, our objective was to study vascular remodeling in case of in utero exposure to maternal diabetes. This is in order to investigate the effect of intra-uterine environment perturbations on vascular fetal programming. We have developed an animal model of rats exposed in utero to moderated maternal hyperglycemia (DMO), which developed an hypertension around 6 months of age.

We analyzed structure of elastic and resistance arteries (internal diameter, MCSA, intima-media thickness and remodeling parameters) in absence or presence of established hypertension in male DMO compared to controls (CMO) (at 3 and 18 months of age). Moreover, by in vivo sequential ligation of mesenteric arteries, we have studied vascular remodeling of resistance arteries in response to low (LF), normal (NF) or high flow (HF).

In old DMO, we did not observe any vascular remodeling induced by hypertension neither in aorta nor in mesenteric arteries. This could be related to the increase of smooth muscle cell attachments that we observed. Moreover, after 1 or 3 weeks of mesenteric arteries ligation, DMO did not exhibit any constrictive remodeling in LF although expansive remodeling in HF is maintained. Interestingly, we measured an increase of eNOS activity and GP91 in LF arteries of theses animals although transglutaminase-2 protein expression was not modified.

Our results demonstrate that in utero exposure to maternal diabetes induce modification of vascular remodeling mechanisms in adulthood. Absence of vascular response could be a pre-emptive adaptation to fetal programmed-hypertension in these animals.
Abstract P253: Angiotensin Converting Enzyme Inhibition vs. Angiotensin II Receptor Blockade in Marfan Mouse: Role of Bradykinin
Authors: Gamboa Jorge L , Hill Kevin D , Fowler Susan M , Kon Valentina , Dietz Harry C , Brown Nancy J
Published: March 2022

Angiotensin receptor blockers (ARB) decrease aortic root aneurysm progression in a mouse model of Marfan syndrome, by interfering with angiotensin II (Ang II) activation of transforming growth factor beta (TGF-β) signaling. Angiotensin converting-enzyme inhibitors (ACEi) decrease the formation of Ang II, but also increase bradykinin (BK) which can activate the TGF-β pathway. We tested the hypothesis that ACEi and ARBs differ in their effect on aortic aneurysm development in Fbn1C1039G/+ mice due to different effects on BK. We compared the effect of 12-week treatment with telmisartan (3 and 24 mg/L), ramipril (30mg/L) or placebo in the presence or absence of the BK B2 receptor antagonist HOE140 (0.1 mg/Kg/day). ARB and ACEi reduced blood pressure similarly. ARB and ACEi reduced aortic root diameter (by 17.3±3% and 19.1±5%) but only ARB prevented elastin disruption (Figures 1A and 1B), decreased mast cell infiltration and P-ERK immunoreactivity in the ascending aorta. HOE-140 alone did not reduce the aortic root diameter but diminished the aortic elastin disruption. In the lung, ARB compared to ACEi treatment, prevented the development of emphysematous changes (Figure 1C), decreased mast cell infiltration (4.87±0.98% vs. 9.12±1.23%, p=0.012), and decreased MMP12 (1.02±0.08 vs. 1.52±0.13 A.U, p=0.002) and MMP9 (1.32±0.08 vs. 1.69±0.11 A.U, p=0.006) activity. HOE-140 alone prevented emphysematous changes and decreased MMP12 activity. Endogenous BK contributes to elastin disruption in the aortic root and lung by promoting activation of P-ERK and increasing MMP12 activity, respectively. Clinical studies are required to compare the efficacy of ACEi and ARB in Marfan syndrome.
Abstract P606: Blood Pressure Regulation in Patients with Meniere’s Disease
Authors: Kioseff Dona M , Stewart Deborah L , Harshfield Gregory A
Published: March 2022

Background:
The reason for inner ear fluid buildup in Meniere’s disease patients is unidentified and current treatment is of limited effectiveness. Little is known about the regulation of blood pressure (BP) in this disease. We developed a protocol placing Meniere’s patients under mild mental stress to induce changes in BP. The purpose of this study was to examine BP regulation in Meniere’s patients and provide mechanistic insight into the disease.

Methods:
We measured BP in 9 individuals (5 males, 4 females; 8 Caucasians, 1 African-American) ranging from age 53 to 81. Seven of these subjects were on a range of antihypertensive medications, including ACE inhibitors, aldosterone antagonists, alpha-blockers, beta-blockers, and diuretics. The protocol included 10 minutes of rest, 20 minutes of stress (competitive video game), and 10 minutes of recovery. BP was taken before and after each period and 10 minutes into the stressor.

Results:
Of the 9 subjects, 6 experienced a rise in BP during the stressor. There was a significant increase in systolic blood pressure (SBP) between rest (Rest10) and halfway through the stress protocol (Stress10) and between rest and the beginning of the recovery period (Recov0) as shown in Figure 1.

Conclusions:
According to our study, Meniere’s disease patients exhibit dysregulation of BP that is exaggerated during stress, even while taking a range of antihypertensive medications. After the completion of the stressor, BP remained elevated and continued to rise in some cases. The degree to which these Meniere’s patients are unable to control their BP is potentially clinically significant.
Abstract P607: Deletion of GPER Protects from Age-related Renovascular Dysfunction and Tubulo-interstitial Injury
Authors: Meyer Matthias R , Daniel Christoph , Fredette Natalie C , Amann Kerstin , Barton Matthias , Prossnitz Eric R
Published: March 2022

Aging is associated with reduced vasodilatory capacity in renal arteries. Activation of the G protein-coupled estrogen receptor (GPER) induces vasodilation and improves hypertensive renal injury in rats. Moreover, GPER, as observed with many G protein-coupled receptors, likely exhibits “basal activity” independent of ovarian estrogen production, which may become relevant in disease-like states such as aging. We hypothesized that deletion of basal GPER activity would further aggravate vasodilatory dysfunction in renal arteries and the associated tubulo-interstitial injury. In young (4 month-old) and senescent (24 month-old) male wild-type and GPER-deficient (
Gper

-/-

) mice, blood pressure and endothelium-dependent vasodilation to acetylcholine in renal arteries were determined. In addition, vascular injury (VIS score) and tubulo-interstitial injury (TIS score) including staining for amyloid were quantified in histologic sections. In wild-type mice, aging markedly reduced renal artery vasodilation to acetylcholine (from 77±5% to 28±4% of precontraction, n=4-5, p<0.001 vs. young mice), and increased vascular injury (VIS: 0.42±0.07 vs. 0.04±0.03), tubulo-interstitial injury (TIS: 2.9±0.6 vs. 0.3±0.1), and amyloid staining (2.8±0.7 vs. 0±0, all n=6-8, p<0.001 vs. young mice). Contrary to our hypothesis, vasodilatory responses to acetylcholine were largely preserved in renal arteries from senescent
Gper

-/-

mice (63±4 vs. 28±4% of precontraction, n=4-5, p<0.001 vs. wild-type mice). Similarly, in senescent
Gper

-/-

mice, vascular injury (VIS) was reduced by 46% (n=6-7, p=0.09 vs. wild-type mice), as were tubulo-interstitial injury (TIS) and amyloid staining by 77% and 92%, respectively (both n=6-7, p<0.01 vs. wild-type mice). Deletion of
Gper
had no effect on blood pressure in either senescent (110±5/83±1 vs. 114±2/87±2 mmHg) or young animals (117±2/90±1 vs. 119±2/91±2 mmHg, both n=5-12, p=n.s. vs. wild-type mice). These results indicate a novel role for GPER expression in age-related impaired vasodilatory capacity in renal arteries and the associated tubulo-interstitial injury independent of blood pressure, as well as a pathophysiologically relevant activity of GPER in male mice, possibly independent of estrogen.
Abstract P609: Estrogen Receptor ERα Plays a Major Role in Oxidative Stress Dependent Myocardial Dysfunction Caused by Ethanol in Conscious Female Rats
Authors: Yao Fanrong , A. Abdel-Rahman Abdel
Published: March 2022

Ethanol elicits estrogen (E
2
)-dependent myocardial oxidative stress and dysfunction in female rats. The aim of this study was to elucidate the role of the individual E
2
receptor (ER), ERα, ERβ, and the G protein-coupled estrogen receptor-1 (GPER), in the ethanol-evoked myocardial dysfunction. To achieve this goal, female rats in proestrus phase (highest E
2
level) received selective antagonist (200 μg/kg; i.v) of ERα (MPP), ERβ (PHTPP) or GPER (G15) or saline 30 min before ethanol (1 g/kg; i.v) or saline infusion. ERα blockade virtually abrogated ethanol-evoked myocardial dysfunction and hypotension, while ERβ blockade had no effect on the hypotensive response, but caused delayed attenuation of the ethanol-evoked reductions in left ventricular developed pressure and the rate of left ventricle pressure rise. GPER blockade caused delayed attenuation of both cardiovascular effects of ethanol. While all 3 ERs subtype antagonists attenuated the ethanol-evoked increases in myocardial catalase and ALDH2 activities, ERα blockade also inhibited myocardial catalase activity in the absence of ethanol. Ethanol-evoked elevation in myocardial ROS and enhancement of myocardial Akt, ERK1/2, eNOS and nNOS phosphorylation were attenuated by the 3 ER subtype antagonists. In conclusion, the findings support a greater role for ERα signaling in the E
2
-dependent myocardial oxidative stress and dysfunction caused by ethanol in proestrus rats.
Abstract P614: Renin Angiotensin System: A Placental Perspective
Authors: Siddiqui Athar H , Negi Rahul , Haritha Vemananada , Duraiswami Ramanan , Aziz Nuzhat
Published: March 2022

Renin Angiotensin System (RAS) is a major physiological regulator of Blood Pressure. In pregnancy the placental RAS plays a critical role in maintaining utero-placental blood circulation, necessary for proper fetal development. Proteinuria, a clinical implication of renal injury, is common in hypertensive disorders of pregnancy, including Preeclampsia. In the present study we tried to study whether Proteinuria is a manifestation of the RAS components in placenta. Placenta, collected from the pregnant women was divided in two categories- those having proteinuria and those not. The levels of the Ang II type 1 receptor (AT1), Ang II type 2 receptor (AT2) and ACE2 genes was determined by semi-quantitaive PCR while the Immunoblotting procedure was used to determine the protein levels of the AT1 and AT2 receptors, in the placenta of women of both categories. All the values were normalized with β-actin, used as an internal control. The AT1R gene expression was significantly decreased in the placenta of women exhibiting proteinuria compared to those that did not (0.694±0.116, n=7 vs. 1.250±0.176,n=9 p<0.05), while the levels of AT2R gene expression also showed the same trend (0.9571±0.2206,n=7 vs. 1.960±0.329,n=9,p<0.05). Similarly the levels of ACE2 gene too was significantly decreased in placenta exhibiting proteinuria compared to those which did not exhibit proteinuria (0.2775 ± 0.05747, n=6 vs. 0.2343 ± 0.02277, n=7, p<0.05). The Immuno-blot analysis demonstrated that the levels of AT1R protein were significantly up-regulated in the placenta of the women exhibiting proteinuria compared to those that did not (0.600±0.125,n=5 vs. 0.330±0.046,n=8, p< 0.05), while the levels of AT2R protein was significantly decreased in the placenta of women exhibiting proteinuria compared to those that did not (0.493±0.028, n=5 vs. 0.9963±0.163,n=8, p< 0.05). A differential pattern of the receptor types of Ang II seems to be related with the presence of Proteinuria. The increased AT1 receptor protein function could be accounting for inducing mediators that cause Proteinuria. The effects of AT2 receptor Protein and gene and the ACE2 gene, having a protective role, needs to be elucidated further for mechanistic insights on the actual relationship between the RAS components.
Abstract P619: Teen Obesity Leads To Changes In The Circulatory T Lymphocyte Profile
Authors: De Miguel Carmen , Xu Xiaojing , Pan Yue , Ownby Dennis , Wang Xiaoling , Pollock Jennifer S.
Published: March 2022

Increasing evidence indicates that inflammatory markers exist in cardiovascular patients years prior to disease diagnosis. In addition, obesity is a major risk factor for cardiovascular disease, especially among African Americans. We hypothesized that obesity would lead to different circulating T lymphocyte profiles and activation status in Caucasian and African American teenagers. Lean (BMI < 60th percentile) and obese (BMI ≥ 95th percentile) teenagers (14-20 years-old; n=23-67/group) of both genders and races were recruited from public schools of Augusta, GA. Circulating immune cell phenotypes and activation status were analyzed by fluorescence-activated cell sorting (FACS), and total whole blood cell (WBC) counts were also determined. Obesity was associated with significant reduction of circulating T lymphocyte percentages in white individuals independently of gender (lean vs. obese; CD3+, CD4+ and CD8+ cells, respectively: 29.40±8.14 vs. 25.58±7.53% (p=0.007), 28.51±7.29 vs. 25.95±6.04% (p=0.049) and 5.12±2.6.0 vs. 4.04±1.64% (p=0.013)). A significant decrease in percentages of circulating CD8+ and activated CD8+ cells was also observed in black males (lean vs. obese, CD8+ and CD8+/CD69+: 5.16±2.45 vs. 5.51±2.27% and 0.53±0.49 vs. 0.60±0.55%), but not in black females, indicating that activation of CD8+ cells may be important in the increased prevalence of cardiovascular disease in female African Americans. Interestingly, WBC counts were found to be increased in obese subjects (obese vs. lean: 6.67±2.16 vs. 5.67±1.62 x103/mm3), and, when results were normalized to these counts, obesity was associated with significantly elevated absolute values of circulating CD3+ and CD4+ cells, independently of gender and race. Our analysis also indicates a positive correlation between circulating CD4+ cell percentage and HDL cholesterol (HDLc) in obese whites (r=0.34), and a negative correlation between activated T cells (CD3+/CD69+) percentage and HDLc in obese black males (r=-0.42). In conclusion, teen obesity leads to changes in the circulatory T lymphocyte profile. Moreover, these changes could help to recognize at-risk cardiovascular patients and could be used to prevent the development of the disease in these individuals.
Abstract P621: Cellular Localization of Angiotensin Type 1a Receptor mRNA in the Paraventricular Nucleus of the Hypothalamus
Authors: Liu Meng , De Kloet Annette D , Krause Eric G , Sumners Colin
Published: March 2022

The chronic neurogenic hypertension that involves increased effects of angiotensin II (Ang II) via its type 1 receptor (AT1R) within brain cardiovascular control centers is associated with induction of microglial activation and neuroinflammation in the paraventricular nucleus of the hypothalamus (PVN). However, whether Ang II exerts
direct
effects via AT1R located on microglia is not established. Therefore, the objective of this study was to determine the cellular localization of AT1R in the PVN. Naïve twelve-week old normotensive (Sprague Dawley, SD; Wistar Kyoto, WKY) rats and spontaneously hypertensive rats (SHR) were euthanized and perfused with 4% paraformaldehyde. Brains were removed and sectioned coronally at the level of the PVN. Sections throughout the entire PVN underwent RNAscope fluorescence
in situ
hybridization to determine AT1aR mRNA expression, combined with immunohistochemistry using microglia (Ionized calcium binding adaptor molecule 1; Iba1)-, neuron (HuC/D)-, or astrocyte (Glial fibrillary acidic protein; GFAP)-specific markers. The results, obtained from at least 3 SD and 3 WKY rats indicate strong co-localization of AT1aR transcripts with neurons in the neuroendocrine and parvocellular PVN regions, as expected. By contrast, there was no detectable co-localization of AT1aR mRNA with either microglia or astrocytes throughout the PVN of these rats. Further, qRT-PCR revealed that while both AT1aR- and AT1bR mRNAs were detectable in SD rat hypothalamus (1.00±0.14; 0.40±0.12; n=7), neither transcript was detectable in microglia cultured from the hypothalamus of SD rats (n=6). The pattern of AT1aR mRNA expression in the PVN of SHR, a hypertensive model that exhibits over activity of Ang II/AT1R actions at the PVN, was similar to that observed in the SD and WKY rats, i.e. strong co-localization with HuC/D-positive cells, and no detectable co-localization with either Iba1 or GFAP-positive cells. Collectively, these findings indicate that AT1R are localized to neurons, not glia, in the PVN of normotensive rats or SHR
in situ
. Further, they suggest that it is unlikely that Ang II exerts direct effects at microglia in the PVN, and that induction of microglial activation at this site following Ang II infusion is likely an indirect action.
Abstract P630: Captopril Reduces Cytopathic Effects in Herpes Simplex Virus 1 (HSV-1) Infected SH-SY5Y Cells
Authors: Wofford Amina , Merritt Justin , Jackson Cynthia Ann , Bradford Chastity N , Griffin Gerald
Published: March 2022

Over 60% of the United States population is infected with HSV-1, a double-stranded DNA virus belonging to the Herpesviridae family. HSV-1 is continually documented as a leading infectious cause of corneal blindness and encephalitis. Members of the herpesviridae family have been implicated as cardiovascular pathogens and are independently associated with the future risk of cardiovascular death. Investigations have demonstrated that hypertension may be significantly related to inflammation, a major symptom of HSV-1 infection. Most HSV-1 antivirals are nucleoside analogs which are effective for individuals experiencing current outbreaks, but are limited by the development of antiviral resistance. Thus, there is a need for novel antiviral targets to decrease viral reactivation, a major player in viral associated neuropathologies. In addition to its well-known function of maintaining homeostatic control of arterial and osmotic pressure, components of the Renin Angiotensin System (RAS) have been demonstrated to exert antiviral functions. RAS targets, such as angiotensin peptides and angiotensin type 1 receptors, have been evaluated for their antiviral properties. Yet, the antiviral properties of other currently approved RAS inhibitors have not been investigated. To determine if other RAS components may inhibit viral activity, we tested the hypothesis that captopril, an inhibitor of angiotensin converting enzyme 1 (ACE), attenuates cytopathic effects of HSV-1 in SH-SY5Y, human neuroblastoma, cells. Photomicrographs of SH-SY5Y cells demonstrated that captopril protects cells from HSV-1-induced cytopathic effects. Additionally, cell viability assays revealed that captopril reduced HSV-1-induced cellular death by 18% (p-value<.05, compared to vehicle treated HSV-1 infected cells). Preliminary viral entry assay data suggests captopril may exert antiviral effects through entry inhibition as demonstrated by a 14.18% decrease in GFP immunofluorescence after captopril-treated cells were exposed to a GFP-expressing HSV-1 recombinant virus for 48h (compared to their untreated, uninfected counterparts). These results support captopril as a therapeutic target for the treatment of HSV-1 and its associated pathologies.
Abstract P631: Cholesterol Is Required To Maintain T-tubule Integrity And Intercellular Connections At Intercalated Discs In Cardiomyocytes
Authors: zhu Yanqi , Zhang Caimei , Chen Rong , Chen Biyi , Guo Ang , Hong Jiang , Song Longsheng
Published: March 2022

Aims:
Low serum cholesterol levels are associated with cardiac arrhythmias and poor prognosis in patients with chronic heart failure. However, the underlying mechanisms by which decreases in cholesterol content lead to cardiac dysfunction remain unclear. Multiple studies have implicated damage to cardiac transverse (T)-tubules as a key mediator of excitation-contraction (E-C) coupling dysfunction and heart failure. Since the T-tubule membrane system is enriched in cholesterol, we hypothesized that depletion of membrane cholesterol promotes T-tubule remodeling and E-C coupling dysfunction.

Methods and Results:
We first examined the impact of membrane cholesterol depletion on T-tubule architecture by treating isolated C57BL/6 murine cardiomyocytes with methyl-β-cyclodextrin (MβCD). T-tubule structural integrity was progressively decreased by MβCD in a concentration- and time-dependent manner. Membrane cholesterol depletion also promoted in a severe decrease in the amplitude and frequency of Ca2+ transients and an increase in the number and amplitude of spontaneous Ca2+ sparks. Reintroduction of cholesterol restored T-tubule integrity and Ca2+ handling properties in acutely-treated myocytes and slowed down T-tubule deterioration in response to chronic MβCD exposure. Studies were extended to determine the impact of membrane cholesterol depletion on T-tubule structure in intact hearts. In addition to T-tubule remodeling, Langendorff perfusion of MβCD resulted in rapid and severe disruption of the intercellular connections between cardiomyocytes, in particular at intercalated disc regions in intact hearts.

Conclusions:
These data provide the first evidence that cholesterol plays a critical role in maintaining cardiac T-tubule structure and the integrity of intercalated discs.
Abstract P635: Improvement of Cardiovascular Outcomes in Diabetic Rats by a Novel Angiotensin II Receptor Peptide Agonist
Authors: Pulakat Lakshmi , Carmack Terry , DeMarco Vincent G , Ardhanari Sivakumar , Kumar Senthil A
Published: March 2022

Diabetes Mellitus (DM) is an independent predictor of cardiovascular disease (CVD). Recent reports show that Angiotensin II type 2 receptor (AT2R) promotes cardiac repair after myocardial infarction. Therefore, we hypothesized that activation of AT2R would improve cardiac function in diabetic rats. Male Zucker obese (ZO) rats are leptin receptor–deficient and exhibit hyperphagia, obesity, insulin resistance and hyperlipidemia. They are a widely used rodent model for early stage Type 2 DM (T2DM). We and others have reported that male ZO rats exhibit diastolic and systolic dysfunction. Therefore we investigated whether a two week treatment with an AT2R agonist could improve cardiac functions of young male ZO rats. Thirteen-week old male ZO rats were subjected to daily intraperitoneal injections (0.9mg/kg/day) with a novel peptide AT2R agonist, NP-6A4 (from Novopyxis, Inc.) dissolved in saline (n=7) or saline only (n=6) for two weeks. Conventional echocardiography and speckle tracking strain analysis were performed using a Vevo 2100 (visualsonics) small animal ultrasound system. Fasting (6 hours) plasma analysis showed that triglycerides (mg/dL) were significantly reduced in response to treatment (ZO+ Saline=1229±164; ZO+NP-6A4= 610±109; p<0.015). Importantly, NP-6A4 treatment improved E/E’ ratio (ZO+Saline= 32.3±2.06; ZO+NP-6A4= 26±2.1; p<0.005), which indicates a significant improvement in diastolic dysfunction. A unit rise in the E/E' ratio is associated with a 17% increment in risk of a cardiac event. Moreover, myocardial performance index of NP-6A4 treated rats was also reduced (ZO+ Saline= 0.516±0.03; ZO+ NP-6A4= 0.389±0.02; p<0.006). Finally, circumferential strain (deg/sec) of endocardium (short axis view) was also significantly improved in response to treatment, while no significant changes were observed in radial or longitudinal strains (ZO+ Saline= -20.56±1.65; ZO+ NP-6A4= -26.11±2.47; p<0.024). Collectively, these data suggest that activation of the AT2R by NP-6A4 had significant lipid lowering effect and improved diastolic and systolic functions in diabetic rats.
Abstract P638: Investigating Gene Pleiotropy in the Metabolic Syndrome in Lyon Hypertensive Rats
Authors: Kwitek Anne E , Pettus Janette , Jakoubek Jessica , Ma John
Published: March 2022

The metabolic syndrome (MetS) - hypertension, obesity, dyslipidemia, and insulin resistance - is a major risk factor for cardiovascular disease and stroke. Our overall goal is to identify novel genes and pathways causing MetS. Our previous work determined that rat chromosome 17 (RNO17) contributes to several MetS-defining traits (including high blood pressure, obesity, and dyslipidemia) in the Lyon Hypertensive (LH) rat, a genetically determined MetS rat model. We hypothesized that at least some of the traits on RNO17 are controlled by a single gene with pleiotropic effects. To address this hypothesis, we generated congenic strains where a defined fragment of RNO17 from the LH rat was substituted by that of the control Lyon Normotensive (LN) rat, and measured MetS phenotypes. One congenic (LH-17
LN
a), with the proximal 30 Mb of RNO17 from the LH genome substituted with that of the LN genome, did not show significant differences from the LH parental strain. However, another congenic strain (LH-17
LN
c), with a substituted fragment at the distal end of RNO17 (84-97 Mb), showed significant differences from the LH rat in serum total cholesterol (3.15 ± 0.15 vs. 4.29 ± 0.17 mMol; p<0.01) and triglycerides (0.47 ± 0.06 vs. 1.27± 0.13 mMol; p<0.001), and a trend for reduced blood pressure (SBP 150.8 ± 3.4 vs. 157.1 ± 1.7 mmHg; p=0.1). Interestingly, there was no difference in body weight between the LH-17
LN
c and the parental LH rat (440 + 7.2 vs. 435 + 9.1 g). These data indicate that serum cholesterol and triglycerides, and possibly blood pressure are regulated by a gene(s) in the distal congenic interval, and could be due to pleiotropy. The data also indicate body weight is not determined by the same gene(s). Interestingly, only two small haplotypes spanning a total of 1 Mb differ between the LH and LN genomes in the congenic interval. Genes in these haplotypes are being studied as candidate genes for causing dyslipidemia in the LH rat. Overall MetS, even in a simplified genetic model such as the LH-17
LN
rat, is likely due to both independent and pleiotropic gene effects.
Abstract P640: Endogenous microRNAs in Human Microvascular Endothelial Cells Regulate mRNAs Encoded by Hypertension-Related Genes and Are Functionally Important
Authors: Kriegel Alison J , Baker Maria A , Liu Yong , Liu Pengyuan , Cowley Allen W , Liang Mingyu
Published: March 2022

Relatively few miRNA-target pairs have been shown to be involved in hypertension or physiological processes related to blood pressure regulation. The goal of the present study was to systematically identify endogenous microRNAs in endothelial cells that regulate mRNAs encoded by genes relevant to hypertension. Small RNA deep sequencing was performed in cultured human microvascular endothelial cells (HMVEC-D) to identify abundant miRNAs. Of the 50 most abundant microRNAs identified, 30 had predicted target mRNAs encoded by genes with known involvement in hypertension or blood pressure regulation. HMVEC-D were transfected with anti-miR oligonucleotides to inhibit each of the 30 microRNAs and the mRNA abundance of predicted targets was measured by qRT-PCR. Of 95 microRNA-target pairs examined, the target mRNAs were significantly up-regulated in 35 pairs and paradoxically down-regulated in 8 pairs. The functional relevance of miRNAs targeting
JAG1
(miR-21-5p) and
NOX4
(miR-92a-3p, miR-92b-3p, miR-100-5p, and miR-99b-5p), was tested in in vivo and in vitro models, respectively. Blood pressure was measured with radiotelemetry in C57BL/6J mice receiving LNA anti-miR-21 or scrambled LNA anti-miR (n=4/group; 10mg/kg; i.p.). LNA anti-miR-21 induced a transient increase in arterial pressure in mice fed a 0.4% NaCl diet, but a significant and sustained reduction of 24 hour averaged mean arterial pressure on a 4.0% NaCl diet, reaching 96.3 ± 4.0 mmHg compared to 105.3 ± 1.6 mmHg (mean ± SEM) in mice treated with scrambled anti-miR (p<0.05). The release of H
2
O
2
from HMVEC-D was measured by Amplex Red assay 48 hours after transfection with anti-miRs identified to increase
NOX4
mRNA abundance or scrambled anti-miR (n=6-12/group). The release of H
2
O
2
from HMVEC-D was significantly increased following transfection of anti-miRs for miR-92a-3p, miR-92b-3p, miR-99b-5p, and miR-100b-5p by 82.2% to 139.6%. These findings indicate widespread, tonic control of mRNA abundance of genes relevant to blood pressure regulation by endothelial microRNAs that are functionally significant.
Abstract P643: Proliferative Potential of Perivascular Adipose Tissue Stromal Vascular Cells Is Dependent on Anatomical Site
Authors: Contreras G. Andres , Thelen Kyan , Ayala-Lopez Nadia , Watts Stephanie W
Published: March 2022

Perivascular adipose tissue (PVAT) is an important paracrine regulator of blood vessel function. Growth and pathological conditions such as obesity expand PVAT by hyperplasia and hypertrophy, however, these remodeling processes may differ depending on the PVAT anatomical site leading to diverse effects on the vasculature. A higher proliferative capacity of PVAT localized around mesenteric arteries may contribute to increased visceral fat mass and therefore intensify CVD risk. We hypothesize that PVAT proliferative potential is dependent on PVAT anatomical localization. PVATs from aorta (aPVAT) and mesenteric arteries (mPVAT) were collected from male Sprague Dawley rats at 10 weeks of age (n=5). Visceral depots including gonadal (GON) and retroperitoneal (RP), and the subcutaneous inguinal pad (SC) were collected as non-perivascular adipose controls. Stromal vascular fraction cells (SVF) from each adipose site were harvested and flow cytometry was performed to assess their expression of surface markers for committed preadipocyte precursors including CD34, CD44, and CD140a. Cells co-expressing these markers have high adipogenic capacity and are highly proliferative in visceral adipose tissues during obesity. No differences among sites were observed in the percentage of SVF cells expressing CD34 (aPVAT 39.3%±9.1; mPVAT 46.4%±11.16; GON 51.15%±14.11; RP 37.68%±5.6; SC 29.74%±2.5) and CD140a (aPVAT 1.43%±0.65; mPVAT 3.54%±1.33; GON 3.53%±0.36; RP 1.95%±0.91; SC 2.42%±0.81). There was a higher number of CD44
+
SVF in mPVAT (3.93%±0.8) and GON (4.4%±1.11) compared to aPVAT, RP, and SC (1.4%±0.13; 1.53%±0.53; 2.08±0.37.
P
<0.05). Proliferation capacity of SVF was evaluated by plating 2x10
5
cells/cm
2
of PVATs and GON, as highly proliferative and adipogenic control site, supplemented with DMEM:F12 media (10%FBS). At 11 days in culture, the number of SVF/cm
2
was significantly lower in aPVAT (7.04x10
5
cells/cm
2
) vs. mPVAT and GON (13.75 x10
5
and 12.62 x10
5
cells/cm
2
;
P
<0.05). These data demonstrate a site dependent proliferation capacity of SVF cells from PVATs that may be explained in part by differences in the cellular distribution of adipocyte progenitors.