Abstract 080: mTORC1 as a Novel Regulator of Vascular Endothelial Function in Obese Mice and Humans

Obesity-induced hypertension is associated with vascular endothelial dysfunction. Recently, our laboratory has demonstrated a critical role of the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway in cardiovascular regulation. Here, we tested the hypothesis that dysregulation of mTORC1 signaling is involved in the endothelial dysfunction associated with obesity in mice and humans. We found that diet-induced obese (DIO) mice that display vascular endothelial dysfunction as compared to lean controls have increased mTORC1 signaling in aortic lysates indicated by the elevated (p<0.05) phosphorylated levels of mTOR and its downstream signaling targets S6-kinase and the ribosomal S6 protein measured by Western blot. Increased vascular mTORC1 signaling in DIO mice was associated with increased aortic NOX2 mRNA expression (2.0±0.2 vs. 1.0±0.3AU in lean controls; p<0.05). Isolated abdominal subcutaneous adipose arterioles from non-diabetic obese (BMI ≥30 kg/m 2 ; n=4; age 51±6 yrs; BMI 54±3 kg/m 2 ) humans exhibited a strong trend towards increased phosphorylated S6 protein compared to normal-weight (BMI <30kg/m 2 ; n=3; age 44±15 yrs; BMI 26±1 kg/m 2 ) individuals (5.0±1.9 vs 0.8±0.4AU; p=0.12), suggesting increased vascular mTORC1 signaling in human obesity. Next, we used an adenoviral construct of a constitutively active (CA) S6-kinase (Ad-CAS6K) to enhance mTORC1 signaling. In mouse endothelial cells, Ad-CAS6K increased mRNA expression of oxidative stress (NOX1and NOX2) and inflammatory markers (IL-1β) and decreased endothelial NOS expression (p<0.05). Transfection of aortic rings with the Ad-CAS6K resulted in impairment in acetylcholine-induced relaxation (Max. relaxation: 67± 5 vs. 81 ±3%; p<0.05) without altering the relaxation evoked by sodium nitroprusside (Max. relaxation: 90±1% vs. 90±2%) recapitulating the vascular phenotype in obese mice. Taken together, our data demonstrate a novel role of the mTORC1 signaling pathway in the regulation of vascular endothelial function. Our data also implicate dysregulation of the endothelial mTORC1 signaling pathway in the endothelial dysfunction associated with obesity.

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Abstract 236: Aldehydes in Cigarette Smoke Impair Vascular Endothelial Function

Circulation Research ◽

10.1161/res.127.suppl_1.236 ◽

2020 ◽

Vol 127 (Suppl_1) ◽

Author(s):

Poonam Rao ◽

Pooneh Nabavizadeh Rafsanjani ◽

Daniel Han ◽

Suzaynn Schick ◽

Matthew Springer

Keyword(s):

Endothelial Dysfunction ◽

Endothelial Function ◽

Cigarette Smoke ◽

Secondhand Smoke ◽

Negative Control ◽

Vascular Endothelial ◽

Vascular Endothelial Function ◽

Gas Generation ◽

Post Exposure

Introduction: Exposure to tobacco and marijuana smoke impairs vascular endothelial function. While the particulate phase of smoke is heavily implicated, the role of volatile constituents is unclear. Smoke contains aldehydes, which are known to cause endothelial dysfunction. We explored whether two aldehydes found in smoke, acrolein and acetaldehyde, can induce endothelial dysfunction. Hypothesis: Aldehydes in smoke impair endothelial function. Methods: We exposed 4 groups of anesthetized rats to 3 ppm acrolein and 10-11.5 ppm acetaldehyde gases (concentrations relevant to levels in secondhand smoke), Marlboro Red cigarette sidestream smoke at modest levels (600 μg/m 3 PM2.5) as a positive control, and clean air through the gas generation system as a negative control. Exposure was continuous for 10 minutes. Endothelial function (flow-mediated dilation; FMD) was quantified pre- and post-exposure by measuring femoral artery diameter with ultrasound before and after 5 min of transient ischemia and expressed as % vasodilation. Results: Impairment of FMD was observed for acrolein (10.8±1.7(SD)% vs. 5.8±2.9%, p=.001), acetaldehyde (8.8±2.0% vs. 6.0±2.5%, p=.001), and cigarette smoke (9.4±2.9% vs. 5.8±2.0%, p=.002), but not for air (7.9±2.0% vs. 9±3.2%, p=.44) (figure; each colored line denotes a rat pre- and post-exposure; bars denote means). Conclusions: Acrolein and acetaldehyde at levels found in secondhand smoke impair endothelial function. Our results suggest that despite a potential role of particles, volatile aldehydes may mediate part of the endothelial dysfunction caused by exposure to smoke.

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Endothelial cell senescence with aging in healthy humans: prevention by habitual exercise and relation to vascular endothelial function

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00416.2017 ◽

2017 ◽

Vol 313 (5) ◽

pp. H890-H895 ◽

Cited By ~ 48

Author(s):

Matthew J. Rossman ◽

Rachelle E. Kaplon ◽

Sierra D. Hill ◽

Molly N. McNamara ◽

Jessica R. Santos-Parker ◽

...

Keyword(s):

Endothelial Cell ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Cell Senescence ◽

Vascular Endothelial ◽

Vascular Endothelial Dysfunction ◽

Vascular Endothelial Function ◽

Healthy Humans ◽

Age Related ◽

Habitual Exercise

Cellular senescence is emerging as a key mechanism of age-related vascular endothelial dysfunction, but evidence in healthy humans is lacking. Moreover, the influence of lifestyle factors such as habitual exercise on endothelial cell (EC) senescence is unknown. We tested the hypothesis that EC senescence increases with sedentary, but not physically active, aging and is associated with vascular endothelial dysfunction. Protein expression (quantitative immunofluorescence) of p53, a transcription factor related to increased cellular senescence, and the cyclin-dependent kinase inhibitors p21 and p16 were 116%, 119%, and 128% greater (all P < 0.05), respectively, in ECs obtained from antecubital veins of older sedentary (60 ± 1 yr, n = 12) versus young sedentary (22 ± 1 yr, n = 9) adults. These age-related differences were not present (all P > 0.05) in venous ECs from older exercising adults (57 ± 1 yr, n = 13). Furthermore, venous EC protein levels of p53 ( r = −0.49, P = 0.003), p21 ( r = −0.38, P = 0.03), and p16 ( r = −0.58, P = 0.002) were inversely associated with vascular endothelial function (brachial artery flow-mediated dilation). Similarly, protein expression of p53 and p21 was 26% and 23% higher (both P < 0.05), respectively, in ECs sampled from brachial arteries of healthy older sedentary (63 ± 1 yr, n = 18) versus young sedentary (25 ± 1 yr, n = 9) adults; age-related changes in arterial EC p53 and p21 expression were not observed ( P > 0.05) in older habitually exercising adults (59 ± 1 yr, n = 14). These data indicate that EC senescence is associated with sedentary aging and is linked to endothelial dysfunction. Moreover, these data suggest that prevention of EC senescence may be one mechanism by which aerobic exercise protects against endothelial dysfunction with age. NEW & NOTEWORTHY Our study provides novel evidence in humans of increased endothelial cell senescence with sedentary aging, which is associated with impaired vascular endothelial function. Furthermore, our data suggest an absence of age-related increases in endothelial cell senescence in older exercising adults, which is linked with preserved vascular endothelial function. Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/aging-exercise-and-endothelial-cell-senescence/ .

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Abstract 041: Elevated Circulating Copeptin in Mid-Gestation is Associated with Increased Aortic Stiffness and Vascular Endothelial Dysfunction in Pregnant Women at High Risk for Preeclampsia

Hypertension ◽

10.1161/hyp.66.suppl_1.041 ◽

2015 ◽

Vol 66 (suppl_1) ◽

Author(s):

Gary L Pierce ◽

Donna A Santillan ◽

Diedre Fleener ◽

Sabrina M Scroggins ◽

Kimberlly K Leslie ◽

...

Keyword(s):

High Risk ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Pregnant Women ◽

Brachial Artery ◽

Aortic Stiffness ◽

Vascular Dysfunction ◽

Vascular Endothelial ◽

Vascular Endothelial Dysfunction ◽

Vascular Endothelial Function

Circulating copeptin, a stable biomarker of vasopressin (AVP) secretion, is elevated throughout pregnancy in women who develop preeclampsia (PreE) and is a strong predictor of PreE as early as the 6th week gestation. Reduced vascular endothelial function and increased aortic stiffness occur in mid-gestation before clinical signs/symptoms of PreE manifest, suggesting that maternal vascular dysfunction may be an early event in the pathogenesis of PreE. However, it is unknown whether elevated copeptin/AVP in early/mid gestation contributes to vascular dysfunction in pregnant women who subsequently develop PreE. Therefore, we hypothesized that elevated copeptin would be associated with increased aortic stiffness and reduced vascular endothelial function in early/mid gestation of pregnant women at high risk for PreE. Pregnant women in the 1st trimester (n=72; age=30 ±1 yrs; BMI=34 ± 1 kg/m2) with at least 1 risk factor for PreE were enrolled. Aortic stiffness (carotid-femoral pulse wave velocity, CFPWV), vascular endothelial function (brachial artery flow-mediated dilation, FMD), blood pressure (BP) and plasma copeptin (ELISA) were assessed in both the 1st (11.7 ± 0.2 wks) and 2nd (18.8 ± 0.4 wks) trimesters. In the 1st trimester, CFPWV (7.3 ± 0.2 vs. 7.3 ± 0.5 m/sec, P=0.86), brachial artery FMD (12.9 ± 1.1 vs. 14.3 ± 2.0%, P=0.53), BP, BMI and age did not differ between women in the highest (1513 ± 221 pg/ml) vs. lowest (279 ± 12 pg/ml) quartile of copeptin (P<0.01). In contrast, 2nd trimester CFPWV was greater (7.2 ± 0.2 vs. 6.4 ± 0.2 m/sec, P<0.05) and brachial artery FMD was lower (10.2 ± 2.8 vs. 16.5 ± 1.3 %, P<0.05) among women in the highest (1714 ± 481 pg/ml) vs. the lowest (249 ± 13 pg/ml) quartile of copeptin (P<0.01), in the absence of differences in BP, BMI or age. For the entire cohort, (log)copeptin was significantly correlated with CFPWV (r=0.23, P=0.04) and tended to correlate with FMD (r=-0.23, P=0.06) in the 2nd but not in the 1st trimester. These data suggest that elevated copeptin in mid-gestation is associated with aortic stiffness and vascular endothelial dysfunction in pregnant women at high risk for PreE, but whether increased copeptin/AVP causes vascular dysfunction in pregnancies destined for PreE requires further studies using animal models.

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Endothelial Dysfunction in Cystic Fibrosis: Role of Oxidative Stress

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/1629638 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

Matthew A. Tucker ◽

Brandon M. Fox ◽

Nichole Seigler ◽

Paula Rodriguez-Miguelez ◽

Jacob Looney ◽

...

Keyword(s):

Oxidative Stress ◽

Cystic Fibrosis ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Vascular Dysfunction ◽

Lipid Hydroperoxide ◽

Vascular Endothelial ◽

Vascular Endothelial Dysfunction ◽

Vascular Endothelial Function ◽

Artery Flow

Oxidative stress and vascular endothelial dysfunction are established characteristics of cystic fibrosis (CF). Oxidative stress may contribute to vascular dysfunction via inhibition of nitric oxide (NO) bioavailability. Purpose. To determine if ingestion of a single antioxidant cocktail (AOC) improves vascular endothelial function in patients with CF. Methods. In 18 patients with CF (age 8-39 y), brachial artery flow-mediated dilation (FMD) was assessed using a Doppler ultrasound prior to and two hours following either an AOC (n=18; 1,000 mg vitamin C, 600 IU vitamin E, and 600 mg α-lipoic acid) or a placebo (n=9). In a subgroup of patients (n=9), changes in serum concentrations of α-tocopherol and lipid hydroperoxide (LOOH) were assessed following AOC and placebo. Results. A significant (p=0.032) increase in FMD was observed following AOC (Δ1.9±3.3%), compared to no change following placebo (Δ−0.8±1.9%). Moreover, compared with placebo, AOC prevented the decrease in α-tocopherol (Δ0.48±2.91 vs. −1.98±2.32 μM, p=0.024) and tended to decrease LOOH (Δ−0.2±0.1 vs. 0.1±0.1 μM, p=0.063). Conclusions. These data demonstrate that ingestion of an antioxidant cocktail can improve vascular endothelial function and improve oxidative stress in patients with CF, providing evidence that oxidative stress is a key contributor to vascular endothelial dysfunction in CF.

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Evaluation of Vascular Endothelial Function in Young and Middle-Aged Women with Respect to a History of Pregnancy, Pregnancy-Related Complications, Classical Cardiovascular Risk Factors, and Epigenetics

International Journal of Molecular Sciences ◽

10.3390/ijms21020430 ◽

2020 ◽

Vol 21 (2) ◽

pp. 430 ◽

Cited By ~ 6

Author(s):

Ilona Hromadnikova ◽

Katerina Kotlabova ◽

Lenka Dvorakova ◽

Ladislav Krofta

Keyword(s):

Risk Factors ◽

Cardiovascular Risk ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Peripheral Blood ◽

Vascular Endothelial ◽

Vascular Endothelial Dysfunction ◽

Vascular Endothelial Function ◽

Middle Aged ◽

Cholesterol Levels

The aim of the study was to examine the effect of previous pregnancies and classical cardiovascular risk factors on vascular endothelial function in a group of 264 young and middle-aged women 3 to 11 years postpartum. We examined microvascular functions by peripheral arterial tonometry and EndoPAT 2000 device with respect to a history of gestational hypertension, preeclampsia, fetal growth restriction, the severity of the disease with regard to the degree of clinical signs and delivery date. Besides, we compared Reactive Hyperemia Index (RHI) values and the prevalence of vascular endothelial dysfunction among the groups of women with normal and abnormal values of BMI, waist circumference, systolic and diastolic blood pressures, heart rate, total serum cholesterol levels, serum high-density lipoprotein cholesterol levels, serum low-density lipoprotein cholesterol levels, serum triglycerides levels, serum lipoprotein A levels, serum C-reactive protein levels, serum uric acid levels, and plasma homocysteine levels. Furthermore, we determined the effect of total number of pregnancies and total parity per woman, infertility and blood pressure treatment, presence of trombophilic gene mutations, current smoking of cigarettes, and current hormonal contraceptive use on the vascular endothelial function. We also examined the association between the vascular endothelial function and postpartum whole peripheral blood expression of microRNAs involved in pathogenesis of cardiovascular/cerebrovascular diseases (miR-1-3p, miR-16-5p, miR-17-5p, miR-20a-5p, miR-20b-5p, miR-21-5p, miR-23a-3p, miR-24-3p, miR-26a-5p, miR-29a-3p, miR-92a-3p, miR-100-5p, miR-103a-3p, miR-125b-5p, miR-126-3p, miR-130b-3p, miR-133a-3p, miR-143-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-181a-5p, miR-195-5p, miR-199a-5p, miR-210-3p, miR-221-3p, miR-342-3p, miR-499a-5p, and miR-574-3p). A proportion of overweight women (17.94% and 20.59%) and women with central obesity (18.64% and 21.19%) had significantly lower RHI values at 10.0% false positive rate (FPR) both before and after adjustment of the data for the age of patients. At 10.0% FPR, a proportion of women with vascular endothelial dysfunction (RHI ≤ 1.67) was identified to have up-regulated expression profile of miR-1-3p (11.76%), miR-23a-3p (17.65%), and miR-499a-5p (18.82%) in whole peripheral blood. RHI values also negatively correlated with expression of miR-1-3p, miR-23a-3p, and miR-499a-5p in whole peripheral blood. Otherwise, no significant impact of other studied factors on vascular endothelial function was found. We suppose that screening of these particular microRNAs associated with vascular endothelial dysfunction may help to stratify a highly risky group of young and middle-aged women that would benefit from early implementation of primary prevention strategies. Nevertheless, it is obvious, that vascular endothelial dysfunction is just one out of multiple cardiovascular risk factors which has only a partial impact on abnormal expression of cardiovascular and cerebrovascular disease associated microRNAs in whole peripheral blood of young and middle-aged women.

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GLP-1 Agonists Liraglutide Improved Vascular Endothelial Function in Type 2 Diabetes Rats

10.36502/2020/droa.6168 ◽

2020 ◽

Vol 2 (2) ◽

pp. 46-55

Author(s):

Li X ◽

Wu W ◽

Wang Y ◽

Zhang X ◽

Feng X ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Mesenteric Arteries ◽

Vascular Endothelial ◽

Vascular Endothelial Dysfunction ◽

Vascular Endothelial Function

Objective: Liraglutide (LIRA), a Glucagon-like peptide-1 (GLP-1) receptor agonist, showed potential vascular protective effects with the mechanism remained incompletely understood. Therefore, this study aimed to investigate whether LIRA exerts its effect on vascular endothelial function in rats with type 2 diabetes mellitus (T2DM) via caveolin-1/ endothelial oxide synthase (eNOS) expression. Methods: T2DM rats were used as study subjects and randomly divided into four groups: 1) Veh group, 2) Veh+LIRA group, 3) T2DM group, and 4) T2DM+LIRA group. All rats received either saline or LIRA 0.2 mg/kg (by i.p. injection) per day for 4 weeks. After the model was successfully established, vascular endothelial function was determined the effect of vasodilator to mesenteric artery rings. Immunofluorescence and western blot were performed to understand the molecular mechanism. Cultured HUVECs with small interfering RNA (siRNA) under high glucose (HG), NO concentration, and western blot were performed to understand the molecular mechanism between LIRA and vascular endothelial function. Results: Based on our results, the LIRA reduced hyperglycemia and ameliorated vascular endothelial dysfunction in type 2 diabetic mice. LIRA activated eNOS phosphorylation, suppressing oxidative stress and enhancing endothelium-dependent vasorelaxation of mesenteric arteries. Besides, from its anti-oxidative capacity, LIRA activated eNOS to dilate the mesenteric arteries via the downregulation of Cav-1. Conclusion: LIRA ameliorates vascular endothelial dysfunction in rats with type 2 diabetes mellitus via anti-oxidative and activated eNOS by downregulated Cav-1.

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A Network Pharmacology Analysis to Reveal the Molecular Mechanism of Zhizi-Danshen on Coronary Heart Disease

10.21203/rs.3.rs-85979/v1 ◽

2020 ◽

Author(s):

Yue-hong Shen ◽

Shu-lin Wang ◽

Na Wu ◽

Yu-chen Dai ◽

Qian Zhou ◽

...

Keyword(s):

Coronary Heart Disease ◽

Heart Disease ◽

Endothelial Function ◽

Signaling Pathway ◽

Target Genes ◽

Cardiac Fibrosis ◽

Fluid Shear Stress ◽

Network Pharmacology ◽

Vascular Endothelial ◽

Vascular Endothelial Function

Abstract ObjectiveOur study aimed to investigate the potential mechanisms of the herb pair Zhizi-Danshen (ZD) for coronary heart disease (CHD) using network pharmacological data mining technology.MethodsThe Traditional Chinese Medicine System Pharmacology (TCMSP) database was used to collect the active ingredients of ZD and predict ZD-related target proteins. Afterwards, we identified CHD-related targets from DisGeNET database, NCBI gene database, and TTD database. The common targets both from ZD and CHD were screened by Venny2.1, which were then imported into the String database for protein-protein interaction (PPI) analysis. Finally, the GO and KEGG enrichment analysis were performed by R software, and the network construction was established using Cytoscape3.7.2.ResultsWe obtained 199 possible targets from 62 candidate ingredients of ZD and 1033 CHD-ralated targets, with 83 overlapping common target genes. Then, 11 core targets were acquired from PPI network analysis. Further, GO analysis showed that these common targets mainly influenced receptor ligand activity，cytokine activity，cytokine receptor binding，steroid hormone receptor activity, and peptide binding. KEGG pathway analysis indicated that ZD affected CHD through seven important pathways linked to vascular endothelial function regulation (fluid shear stress and atherosclerosis，AGE-RAGE signaling pathway in diabetic complications, HIF-1 signaling pathway), imflammatory effects (IL-17 signaling pathway, TNF signaling pathway，Toll-like receptor signaling pathway)，and hormone regulation (relaxin signaling pathway). ConclusionsThis study revealed the potential pharmacological mechanisms of ZD against CHD, which were mainly associated with regulation of vascular endothelial function and inflammatory effects, promotion of vasodilatation, and prevention of cardiac fibrosis. Moreover, it provided a novel conception for the development of alternative therapies on CHD.

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