Assessment of endothelial function. History, methodological aspects, and clinical perspectives

The effects of trastuzumab therapy on endothelial functions of breast cancer patients

OBJECTIVE

Breast cancer is among the highest causes of morbidity and mortality in women. Trastuzumab therapy, which is known to be significantly cardiotoxic, is mainly used to treat patients with resistant breast cancer, including estrogen receptor-positive type. We aimed to show the effects of trastuzumab therapy on endothelial functions of breast cancer patients.

METHODS

In this study, a total of 26 participants (24 female and 2 male patients, minimum age: 38 years, maximum age: 79 years, and mean age 57.3±12.7 years) were enrolled in the study. For the statistical evaluation of data, we classified the participants of the study as follows: Pretreatment: Before trastuzumab therapy; Treatment Period 1: 1 month after the first dose of trastuzumab; Treatment Period 2: 4 months after the first dose of trastuzumab; Treatment Period 3: 12 months after the first dose of trastuzumab. We conducted repeated-measures analysis of variance (Greenhouse-Geisser) and paired-sample t-tests to statistically compare the groups using flow-mediated dilation measurements.

RESULTS

We determined that there are statistically significant differences between flow-mediated hyperemia and ratio values (flow-mediated dilation) of the groups (p<0.009 and p<0.001, respectively).

CONCLUSION

Our data indicate that trastuzumab therapy could have negative effects on endothelial functions in breast cancer patients.

Microvascular dysfunction in women with a history of hypertensive disorders of pregnancy: A population-based retrospective cohort study

OBJECTIVE

To evaluate microvascular function in women with previous hypertensive disorders of pregnancy (HDP).

DESIGN

Retrospective population-based cohort study.

SETTING

Linköping, Sweden.

POPULATION

Women aged 50-65 years, participating in the Swedish CArdioPulmonary bioImage Study (SCAPIS) at one site (Linköping) 2016-18, who underwent microcirculatory assessment (N = 1222).

METHODS

Forearm skin comprehensive microcirculatory assessment was performed with a PeriFlux PF6000 EPOS (Enhanced Perfusion and Oxygen Saturation) system measuring oxygen saturation and total speed resolved perfusion. Obstetric records were reviewed to identify women with previous HDP. Data on cardiovascular risk factors, comorbidities, medication, lifestyle, anthropometric data, and biochemical analyses were obtained from SCAPIS. The microcirculatory data were compared between women with and without previous HDP.

MAIN OUTCOME MEASURES

Skin microcirculatory oxygen saturation and total speed resolved perfusion at baseline and post-ischaemic peak.

RESULTS

Women with previous pre-eclampsia displayed impaired post-ischaemic peak oxygen saturation compared with women with normotensive pregnancies (88%, interquartile range [IQR] 84-89% vs 91%, IQR 87-94%, p = 0.001) 6-30 years after pregnancy. The difference remained after multivariable adjustment (β -2.69, 95% CI -4.93 to -0.45).

CONCLUSIONS

The findings reveal microvascular dysfunction at long-term follow up in women with previous pre-eclampsia and strengthen the possible role of endothelial dysfunction as a link to the increased risk of cardiovascular disease in women with HDP.

Endothelial dysfunction, a predictor of cardiovascular disease in HIV patients on antiretroviral therapy: A systematic review and meta-analysis

Aim Although antiretroviral therapy (ART) is available, the rate of new HIV infections is alarming. With this trend, it is anticipated that the use of ART will continue to rise, potentially resulting in associated vascular disorders. Therefore, we aimed to examine the impact of ART on endothelial function in people living with HIV (PLHIV), a predictor of cardiovascular diseases.

METHOD

A comprehensive search for evidence was made on PubMed and Scopus on May 06, 2023, following the Preferred Reporting Items for Systematic Review and Meta-analysis. Cochrane and Newcastle-Ottawa quality assessment scales were used to evaluate quality, while the metaHun web tool and Review Manager version 5.4.1 were used for analysis. Subgroup, sensitivity, and publication bias were conducted for each outcome measure.

RESULTS

We identified 37 studies, including a sample size of 3700 with 2265 individuals on ART. The analyzed evidence showed a large significant effect of ART on vascular cell adhesion molecule-1, with a standardized mean difference (SMD) of -1.23 (95 % CI: -1.72, -0.74; p = 0.0013). Similarly, a significant medium effect of ART was observed on intercellular cell adhesion molecule-1 in PLHIV, with an SMD of -1.28 (95 % CI: -2.00, -0.56; p = 0.0231) compared to the control group. Furthermore, ART exhibited a significant but small effect on flow-mediated dilation (FMD) with an SMD of -0.40 (95 % CI: -0.62, -0.19, p = 0.0159).

CONCLUSION

Our findings show an improved endothelial function in PLHIV on ART, as demonstrated by reduced adhesion molecules; however, ART exhibited a small effect on FMD, thus suggesting PLHIV on ART may still be at risk of endothelial dysfunction and further cardiovascular diseases.

Utilizing venous occlusion plethysmography to assess vascular effects: A study with buloxibutid, an angiotensin II type 2 receptor agonist

Buloxibutid (also known as C21) is a potent and selective angiotensin II type 2 receptor (AT2R) agonist, in development for oral treatment of fibrotic lung disease. This phase I, open-label, pharmacodynamic study investigated vascular effects of buloxibutid in five healthy male volunteers. Subjects were administered intra-arterial infusions of buloxibutid for 5 min in ascending doses of 3, 10, 30, 100, and 200 μg/min, infused sequentially in the forearm. Infusions of sodium nitroprusside (SNP) solution in doses of 0.8-3.2 μg/min were administered as a positive control. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. Safety and tolerability of intra-arterial administrations of buloxibutid were evaluated. Following infusion of buloxibutid in doses of 3-200 μg/min, the range of increase in FBF was 27.8%, 17.2%, 37.0%, 28.5%, and 60.5%, compared to the respective baseline. The largest increase was observed in the highest dose group. Infusions of SNP as a positive control, increased FBF 230-320% compared to baseline. Three adverse events (AEs) of mild intensity, not related to buloxibutid or SNP, were reported for two subjects. Two of these AEs were related to study procedures. There were no clinically relevant changes in arterial blood pressure during the study period. Intra-arterial infusion of buloxibutid in low, ascending doses increased FBF, indicating that buloxibutid may be effective in conditions associated with endothelial dysfunction. Venous occlusion plethysmography was found to be a useful method to explore pharmacodynamic vascular effects of novel AT2R agonists, while avoiding systemic adverse effects.

The Effect of Additional Treatment with Empagliflozin or Semaglutide on Endothelial Function and Arterial Stiffness in Subjects with Type 1 Diabetes Mellitus-ENDIS Study

We investigated the effect of additional treatment with newer antidiabetic drugs on endothelium function and arterial stiffness in subjects with type 1 diabetes mellitus (T1DM) without cardiovascular diseases. A total of 89 participants, all users of CGMS (continuous monitoring glucose system), were randomized into three comparable groups, receiving empagliflozin (E; n = 30), receiving semaglutide (S; n = 30), and a control group (C; n = 29). At baseline and 12 weeks post treatment, we measured FMD (brachial artery flow-mediated dilation) and FBF (forearm blood flow as reactive hyperemia assessed with strain gauge plethysmography) as parameters of endothelial function, as well as pulse wave velocity (PWV) and peripheral resistance as parameters of arterial stiffness. Improvement in FMD was significant in both intervention groups compared to controls (E group 2.0-fold, p = 0.000 and S group 1.9-fold, p = 0.000), with no changes between those two groups (p = 0.745). During the evaluation of FBF, there were statistically insignificant improvements in both therapeutic groups compared to controls (E group 1.39-fold, p = 0.074 and S group 1.22-fold, p = 0.701). In arterial stiffness parameters, improvements were seen only in the semaglutide group, with a decline in peripheral resistance by 5.1% (p = 0.046). We can conclude that, for arterial stiffness, semaglutide seems better, but both drugs positively impact endothelial function and, thus, could also have a protective role in T1DM.

Sirtuin 1 and Vascular Function in Healthy Women and Men: A Randomized Clinical Trial Comparing the Effects of Energy Restriction and Resveratrol

Background: Sirtuin 1 (SIRT1) has been associated with longevity and protection against cardiometabolic diseases, but little is known about how it influences human vascular function. Therefore, this study evaluated the effects of SIRT1 activation by resveratrol and energy restriction on vascular reactivity in adults. Methods: A randomized trial allocated 48 healthy adults (24 women and 24 men), aged 55 to 65 years, to resveratrol supplementation or energy restriction for 30 days. Blood lipids, glucose, insulin, C-reactive protein, noradrenaline, SIRT1 (circulating and gene expression), and flow-mediated vasodilation (FMD) and nitrate-mediated vasodilation (NMD) were measured. Results: Both interventions increased circulating SIRT1 (p < 0.001). Pre- and post-tests changes of plasma noradrenaline were significant for both groups (resveratrol: p = 0.037; energy restriction: p = 0.008). Baseline circulating SIRT1 was inversely correlated with noradrenaline (r = -0.508; p < 0.01), and post-treatment circulating SIRT1 was correlated with NMD (r = 0.433; p < 0.01). Circulating SIRT1 was a predictor of FMD in men (p = 0.045), but not in women. SIRT1 was an independent predictor of NMD (p = 0.026) only in the energy restriction group. Conclusions: Energy restriction and resveratrol increased circulating SIRT1 and reduced sympathetic activity similarly in healthy adults. SIRT1 was independently associated with NMD only in the energy restriction group.

Roles of Oxidative Stress and Inflammation in Vascular Endothelial Dysfunction-Related Disease

Oxidative stress and chronic inflammation play an important role in the pathogenesis of atherosclerosis. Atherosclerosis develops as the first step of vascular endothelial dysfunction induced by complex molecular mechanisms. Vascular endothelial dysfunction leads to oxidative stress and inflammation of vessel walls, which in turn enhances vascular endothelial dysfunction. Vascular endothelial dysfunction and vascular wall oxidative stress and chronic inflammation make a vicious cycle that leads to the development of atherosclerosis. Simultaneously capturing and accurately evaluating the association of vascular endothelial function with oxidative stress and inflammation would be useful for elucidating the pathophysiology of atherosclerosis, determining treatment efficacy, and predicting future cardiovascular complications. Intervention in both areas is expected to inhibit the progression of atherosclerosis and prevent cardiovascular complications.

Noninvasive assessment of foot perfusion in cholesterol-fed rabbits using dynamic volume perfusion CT with an upslope method

To evaluate the feasibility of dynamic foot volume CT with the upslope method and to demonstrate macrovascular reactivity and microvascular perfusion during cuff-induced reactive hyperemia state in cholesterol-fed rabbits. 30 New Zealand male rabbits were divided into 2 groups: dietary hypercholesterolemia (n = 10) and normal diet control (n = 20). To measure for macrovascular reactivity, perfusion parameters of the left posterior tibial artery was measured at baseline and at reactive hyperemia state. For the evaluation of microvascular perfusion, color-coded perfusion map of the plantar dermis was generated for perfusion CT scan by an in-house developed dedicated analysis software based on upslope method. Dermal perfusion values were measured and analyzed before and after cuff-induced reactive hyperemia. Foot dynamic volume CT with the upslope method demonstrated significant impairment of both macrovascular reactivity and microvascular perfusion in cholesterol-fed rabbits without significant macrovascular lesions during cuff-induced reactive hyperemia (CRH) state. Arterial time-to-peak of cholesterol-fed rabbits failed to show acceleration while chow-fed rabbits showed significant decrease in time. Microvascular perfusion calculated by perfusion value (P < 0.01) and perfusion ratio (P = .014) showed decreased microvascular perfusion in cholesterol-fed rabbits compared to chow-fed rabbits during CRH state. Post-CT pathologic examination revealed decreased endothelial cell density in cholesterol-fed rabbits (P < 0.001). Foot perfusion CT using upslope method provides perfusion parameters for large arteries and a perfusion map of the foot during cuff-induced reactive hyperemia in cholesterol-fed rabbits. It may be a useful tool to assess microvascular reactivity in patients with peripheral artery disease but no apparent macrovascular lesions.

A Prediction Equation to Estimate Vascular Endothelial Function in Different Body Mass Index Populations

Objective

Vascular endothelial dysfunction is considered an early predictor of endothelial injury and the initiating factor of atherosclerosis (AS). Brachial artery flow-mediated dilation (FMD) can detect endothelial injury early and provide important prognostic information beyond traditional cardiovascular (CV) risk factors. This study aimed to find the influencing factors of FMD and develop a simple prediction model in populations with different body mass indices (BMIs).

Methods

In total, 420 volunteers with different BMIs were recruited in our study. Subjects were randomly assigned to the derivation and validation cohorts (the ratio of the two was 1:2) with simple random sampling. The former was used for influencing factors searching and model construction of FMD and the latter was used for verification and performance evaluation.

Results

The population was divided into two groups, i.e., 140 people in the derivation group and 280 people in the verification group. Analyzing in the training data, we found that females had higher FMD than males (p < 0.05), and FMD decreased with age (p < 0.05). In people with diabetes, hypertension or obesity, FMD was lower than that in normal individuals (p < 0.05). Through correlation analysis and linear regression, we found the main influencing factors of FMD: BMI, age, waist-to-hip radio (WHR), aspartate aminotransferase (AST) and low-density lipoprotein (LDL). And we developed a simple FMD prediction model: FMD = −0.096BMI−0.069age−4.551WHR−0.015AST−0.242LDL+17.938, where R² = 0.599, and adjusted R² = 0.583. There was no statistically significant difference between the actual FMD and the predicted FMD in the verification group (p > 0.05). The intra-class correlation coefficient (ICC) was 0.77. In a Bland-Altman plot, the actual FMD and the predicted FMD also showed good agreement. This prediction model had good hints in CV risk stratification (area under curve [AUC]: 0.780, 95 % confidence intervals [95% CI]: 0.708–0.852, p < 0.001), with a sensitivity and specificity of 73.8 and 72.1%, respectively.

Conclusions

Males, older, obesity, hypertension, diabetes, smoking, etc. were risk factors for FMD, which was closely related to CV disease (CVD). We developed a simple equation to predict FMD, which showed good agreement between the training and validation groups. And it would greatly simplify clinical work and may help physicians follow up the condition and monitor therapeutic effect. But further validation and modification bears great significance.

Annual reports on hypertension research 2020

In 2020, 199 papers were published in Hypertension Research. Many excellent papers have contributed to progress in research on hypertension. Here, our editorial members have summarized eleven topics from published work and discussed current topics in depth. We hope you enjoy our special feature, Annual Reports on Hypertension Research.

Response of endothelial function and oxidative stress after supervised aerobic exercise training in formerly preeclamptic women

We sought to investigate effects of aerobic exercise in women with preeclampsia history. 42 women were enrolled. After 16 weeks, we found improvement in endothelial function index and oxidative stress biomarkers in the exercise group. Moreover, the change of endothelial function index was significantly associated with the change of total antioxidant capacity in the exercise group. Our findings showed aerobic exercise improved exercise capacity, endothelial function and oxidative stress in formerly preeclamptic women, and favorable modification of oxidative stress might be a vital pathway of endothelial function's melioration in those women, which deserves further exploration.

Association between Flow-Mediated Dilation and Skin Perfusion Pressure with Peripheral Artery Disease in Hemodialysis Patients

Flow-mediated dilation (FMD) is used to noninvasively assess the health of blood vessels and it has been shown to have a similar predictive ability for cardiovascular disease to traditional risk factors. Skin perfusion pressure (SPP) refers to the blood pressure required to restore capillary or microcirculatory flow after controlled occlusion and the return of flow. SPP has been shown to be an important measurement when making clinical decisions for patients with limb ischemia and to be a predictor of the likelihood of wound healing. Peripheral artery disease is common in hemodialysis (HD) patients. However, little is known about the association between FMD or SPP and peripheral artery disease. The aim of this study was to evaluate the association between FMD and SPP with brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) in HD patients in Taiwan, an area with a high rate of ESRD. This study was conducted at a regional hospital in southern Taiwan. ABI and baPWV values were measured using an ABI automated device. FMD and SPP were measured using ultrasound and a microvasculature blood flow monitor, respectively. Eighty patients were enrolled in this study. Compared to the patients with an ABI ≥ 0.95, those with an ABI < 0.95 had lower SPP of the feet (dorsal and plantar portions, both p < 0.001). After multivariable adjustments, low triglycerides (p = 0.033) and high calcium–phosphate product (p = 0.018) were significantly associated with low FMD. Further, low ABI (p = 0.001) and low baPWV (p = 0.036) were significantly associated with low SPP of dorsal portions. Old age (p = 0.005), low high-density lipoprotein cholesterol (p = 0.016), and low ABI (p = 0.002) were significantly associated with low SPP of plantar portions. This study demonstrated an association between FMD and SPP with peripheral artery disease in HD patients. Patients with low ABI and baPWV had a high risk of low SPP of the feet. However, there was no significant correlation between FMD and ABI or baPWV.

Endothelial Function and Arterial Stiffness Should Be Measured to Comprehensively Assess Obstructive Sleep Apnea in Clinical Practice

Objective: An effective clinical tool to assess endothelial function and arterial stiffness in patients with obstructive sleep apnea (OSA) is lacking. This study evaluated the clinical significance of subclinical markers for OSA management in males without serious complications.

Patients/Methods: Males without serious complications were consecutively recruited. Clinical data, biomarker tests, reactive hyperemia index (RHI), and augmentation index at 75 beats/min (AIx75) measured by peripheral arterial tonometry were collected. An apnea hypopnea index (AHI) cutoff of ≥15 events/h divided the patients into two groups.

Results: Of the 75 subjects, 42 had an AHI ≥15 events/h. Patients with an AHI ≥15 events/h had higher high-sensitivity C-reactive protein, tumor necrosis factor-alpha (TNF-α), vascular endothelial growth factor, and AIx75 values than the control group but no statistical difference in RHI was observed. After controlling for confounders, TNF-α was negatively correlated with the average oxygen saturation (r = −0.258, P = 0.043). RHI was correlated with the rapid eye movement (REM) stage percentage (r = 0.306, P = 0.016) but not with AHI (P > 0.05). AIx75 was positively correlated with the arousal index (r = 0.289, P = 0.023) but not with AHI (r = 0.248, P = 0.052).

Conclusions: In males with OSA without severe complications, TNF-α and AIx75 are independently related to OSA. The role of RHI in OSA management requires further elucidation. These markers combined can comprehensively evaluate OSA patients to provide more evidence for the primary prevention of coronary heart disease and treatment response assessment.

Low-Intensity Focused Ultrasound-Responsive Ferrite-Encapsulated Nanoparticles for Atherosclerotic Plaque Neovascularization Theranostics

Pathological angiogenesis is a crucial factor that causes atherosclerotic plaque rupture. Sinoporphyrin sodium-mediated sonodynamic therapy (DVDMS-SDT) induces regression of plaque neovascularization in humans without causing obvious side effects. However, a clinical noninvasive theranostic strategy for atherosclerotic plaque neovascularization is urgently needed. A nanoplatform designed for multimodality imaging-guided SDT in plaque angiogenesis theranostics, termed PFP-HMME@PLGA/MnFe2 O4 -ramucirumab nanoparticles (PHPMR NPs), is fabricated. It encapsulates manganese ferrite (MnFe2 O4 ), hematoporphyrin monomethyl ether (HMME), and perfluoropentane (PFP) stabilized by polylactic acid-glycolic acid (PLGA) shells and is conjugated to an anti-VEGFR-2 antibody. With excellent magnetic resonance imaging (MRI)/photoacoustic/ultrasound imaging ability, the distribution of PHPMR NPs in plaque can be observed in real time. Additionally, they actively accumulate in the mitochondria of rabbit aortic endothelial cells (RAECs), and the PHPMR NP-mediated SDT promotes mitochondrial-caspase apoptosis via the production of reactive oxygen species and inhibits the proliferation, migration, and tubulogenesis of RAECs. On day 3, PHPMR NP-mediated SDT induces apoptosis in neovessel endothelial cells and improves hypoxia in the rabbit advanced plaque. On day 28, PHPMR NP-mediated SDT reduces the density of neovessels, subsequently inhibiting intraplaque hemorrhage and inflammation and eventually stabilizing the plaque. Collectively, PHPMR NP-mediated SDT presents a safe and effective theranostic strategy for inhibiting plaque angiogenesis.

Lower triglyceride levels are associated with better endothelial function

BACKGROUND

Increased serum triglyceride levels are independently associated with endothelial dysfunction. However, there is little evidence to define normal levels of triglycerides and there is little information on endothelial function in subjects with extremely low levels of triglycerides.

OBJECTIVE

The purpose of this study was to determine the relationship between triglycerides, especially low levels of triglycerides, and vascular function.

METHODS

We measured flow-mediated vasodilation (FMD) in 7047 subjects and nitroglycerine-induced vasodilation (NID) in 1017 subjects. We divided the subjects into eight groups by triglyceride levels: <50 mg/dL, 50-69 mg/dL, 70-89 mg/dL, 90-109 mg/dL, 110-129 mg/dL, 130-149 mg/dL, 150-199 mg/dL, and ≥200 mg/dL.

RESULTS

FMD was significantly higher in subjects with triglyceride levels of <50 mg/dL than in subjects with triglyceride levels of 50-69 mg/dL, 70-89 mg/dL, 90-109 mg/dL, 110-129 mg/dL, 130-149 mg/dL, 150-199 mg/dL, and ≥200 mg/dL (p=0.002, p<0.001, p<0.001, p<0.001, p<0.001, p<0.001, and p<0.001, respectively). Using triglyceride levels of >200 mg/dL as a reference, the odds ratios for a lower quartile of FMD were significantly lower in the <50 mg/dL group, 50-69 mg/dL group, 70-89 mg/dL group, and 90-109 mg/dL group after adjustment for age, gender and other cardiovascular risk factors. There was a slight negative correlation between NID and triglycerides (r=-0.074; p=0.019). However, there was no significant differences in NID among the eight groups.

CONCLUSIONS

FMD values were highest in subjects with extremely low levels of triglycerides (<50 mg/dL). Lower triglyceride levels were associated with better endothelial function.

CLINICAL TRIAL REGISTRATION INFORMATION

http://www.umin.ac.jp (University Hospital Medical Information Network Clinical Trials Registry) (UMIN000012950).

Comparison of biomarkers of endothelial dysfunction and microvascular endothelial function in patients with primary aldosteronism and essential hypertension

Introduction:

Studies have shown that primary aldosteronism (PA) has a higher risk of cardiovascular events than essential hypertension (EH). Endothelial dysfunction is an independent predictor of cardiovascular events. Whether PA and EH differ in the endothelial dysfunction is uncertain. Our study was designed to investigate the levels of biomarkers of endothelial dysfunction (Asymmetric dimethylarginine, ADMA; E-selectin, and Plasminogen activator inhibitor-1, PAI-1) and assess the microvascular endothelial function in patients with PA and EH, respectively.

Methods:

The biomarkers of endothelial dysfunction were measured by enzyme-linked immunosorbent assay (ELISA). Microvascular endothelial function was evaluated by Pulse amplitude tonometry (PAT).

Results:

Thirty-one subjects with EH and 36 subjects with PA including 22 with aldosterone-producing adenoma (APA) and 14 with idiopathic hyperaldosteronism (IHA) were enrolled in our study. The ADMA levels among the three groups were different (APA 47.83 (27.50, 87.74) ng/ml vs EH 25.08 (22.44, 39.79) ng/ml vs IHA 26.00 (22.23, 33.75) ng/ml; p = 0.04), however, when the APA group was compared with EH and IHA group, there was no statistical significance (47.83 (27.50, 87.74) ng/ml vs 25.08 (22.44, 39.79) ng/ml for EH, p = 0.11; 47.83 (27.50, 87.74) ng/ml vs IHA 26.00 (33.75) ng/ml, p = 0.07). The results of ADMA levels are presented as Median (p25, p75). Whereas, levels of PAI-1 and E-selectin, microvascular endothelial function were not significantly different between PA and EH subjects.

Conclusions:

Our study shows no significant differences between PA and EH in terms of biomarkers of endothelial dysfunction and microvascular endothelial function. The microvascular endothelial function of PA and EH patients is comparable.

Endothelial and Autonomic Functions in Patients with Migraine

OBJECTIVE

It has been shown that patients with migraine have endothelial dysfunction. Migraine patients with aura, especially, have more clinical manifestations of autonomic nervous system dysfunction. We aimed to evaluate the endothelial and autonomic functions in migraine patients during both migraine headache attack and headache-free periods.

DESIGN

This was a cross-sectional, randomized study.

SUBJECTS AND METHODS

A total of 130 participants (67 male and 63 female patients, minimum age = 19 years, maximum age = 71 years, mean age = 38.8 ± 12.2 years) were enrolled into the study. For the statistical evaluation of data, we classified the participants of the study as follows: group 1: headache (+) aura (+); group 2: headache (+) aura (-); group 3: headache (-) aura (+); group 4: headache (-) aura (-). Noninvasive evaluation of endothelial function was performed by flow-mediated dilation (FMD) and pulse wave analysis methods. Heart rate variability measurements were used for noninvasive evaluation of autonomic functions.

RESULTS

Group 1 had a higher FMD ratio than the control group, group 3, or group 4 (P < 0.001, P < 0.001, and P = 0.003, respectively). Group 4 had lower FMD ratio levels than the other migraine groups and or the control group (P < 0.001). Group 3 had the highest high-frequency (HF) power levels among all migraine groups (P < 0.001). Group 2 had higher low-frequency/HF ratio values than other migraineurs (P < 0.001).

CONCLUSIONS

We concluded that endothelial dysfunction and headache are closely related. Additionally, higher parasympathetic tonus might be associated with the presence of aura.

Influencing factors of vascular endothelial function in patients with non-obstructive coronary atherosclerosis: a 1-year observational study

BACKGROUND

Endothelial dysfunction may play a key role in non-obstructive coronary artery atherosclerosis. Our study aimed to evaluate the vascular endothelial function and its influencing factors in patients with non-obstructive coronary artery atherosclerosis.

METHODS

A total of 131 consecutive patients with non-obstructive coronary artery atherosclerosis were enrolled. Flow-mediated dilatation (FMD) was measured at baseline and 1-year follow-up. Endothelial progenitor cells (EPCs) were counted by staining the fasting venous blood with antibodies against CD34 and vascular endothelial growth factor receptor 2.

RESULTS

Systolic blood pressure, pulse pressure and the levels of HbA1c in participants with baseline FMD < 6% (n = 65) were significantly higher than those with baseline FMD ≥ 6% (n = 66). Baseline FMD was negatively associated with EPC counts (r = - 0.199, P < 0.05) and systolic blood pressure (r = - 0.315, P < 0.01). The 1-year FMD was significantly increased compared to the baseline FMD [(9.31 ± 5.62) % vs (7.31 ± 5.26) %, P < 0.001]. Independent predictors of FMD improvement included elevated EPC counts (OR = 1.104, 95% CI: 1.047-1.165, P < 0.001) and decreased levels of serum creatinine (OR = 0.915, 95% CI: 0.843-0.993, P = 0.034).

CONCLUSIONS

Family history of premature cardiovascular diseases, hypertension, elevated systolic pressure, and HbA1c > 6.5% are independent risk factors for endothelial dysfunction in non-obstructive atherosclerotic patients. Elevated peripheral blood EPC counts and decreased levels of serum creatinine are independent predictors of endothelial function improvement.

Diagnostic Criteria of Flow-Mediated Vasodilation for Normal Endothelial Function and Nitroglycerin-Induced Vasodilation for Normal Vascular Smooth Muscle Function of the Brachial Artery

Background

Diagnostic criteria of flow‐mediated vasodilation (FMD), an index of endothelial function, and nitroglycerin‐induced vasodilation (NID), an index of vascular smooth muscle function, of the brachial artery have not been established. The purpose of this study was to propose diagnostic criteria of FMD and NID for normal endothelial function and normal vascular smooth muscle function.

Methods and Results

We investigated the cutoff values of FMD and NID in subjects with (risk group) and those without cardiovascular risk factors or cardiovascular diseases (no‐risk group) in 7277 Japanese subjects (mean age 51.4±10.8 years) from the Flow‐Mediated Dilation Japan study and the Flow‐Mediated Dilatation Japan Registry study for analysis of the cutoff value of FMD and in 1764 Japanese subjects (62.2±16.1 years) from the registry of Hiroshima University Hospital for analysis of the cutoff value of NID. Receiver‐operator characteristic curve analysis of FMD to discriminate subjects in the no‐risk group from patients in the risk group showed that the optimal cutoff value of FMD to diagnose subjects in the no‐risk group was 7.1%. Receiver‐operator characteristic curve analysis of NID to discriminate subjects in the no‐risk group from patients in the risk group showed that the optimal cutoff value of NID to diagnose subjects in the no‐risk group was 15.6%.

Conclusions

We propose that the cutoff value for normal endothelial function assessed by FMD of the brachial artery is 7.1% and that the cutoff value for normal vascular smooth muscle function assessed by NID of the brachial artery is 15.6% in Japanese subjects.

Clinical Trial Registration

http://www.umin.ac.jp Unique identifiers: UMIN000012950, UMIN000012951, UMIN000012952, and UMIN000003409

Remote ischemic conditioning: a promising therapeutic intervention for multi-organ protection

Despite decades of formidable exploration, multi-organ ischemia-reperfusion injury (IRI) encountered, particularly amongst elderly patients with clinical scenarios, such as age-related arteriosclerotic vascular disease, heart surgery and organ transplantation, is still an unsettled conundrum that besets clinicians. Remote ischemic conditioning (RIC), delivered via transient, repetitive noninvasive IR interventions to distant organs or tissues, is regarded as an innovative approach against IRI. Based on the available evidence, RIC holds the potential of affording protection to multiple organs or tissues, which include not only the heart and brain, but also others that are likely susceptible to IRI, such as the kidney, lung, liver and skin. Neuronal and humoral signaling pathways appear to play requisite roles in the mechanisms of RIC-related beneficial effects, and these pathways also display inseparable interactions with each other. So far, several hurdles lying ahead of clinical translation that remain to be settled, such as establishment of biomarkers, modification of RIC regimen, and deep understanding of underlying minutiae through which RIC exerts its powerful function. As this approach has garnered an increasing interest, herein, we aim to encapsulate an overview of the basic concept and postulated protective mechanisms of RIC, highlight the main findings from proof-of-concept clinical studies in various clinical scenarios, and also to discuss potential obstacles that remain to be conquered. More well designed and comprehensive experimental work or clinical trials are warranted in future research to confirm whether RIC could be utilized as a non-invasive, inexpensive and efficient adjunct therapeutic intervention method for multi-organ protection.

Tumor necrosis factor inhibitors are associated with reduced complement activation in spondylarthropathies: An observational study

BACKGROUND

The complement system is involved in pathogenesis of cardiovascular disease, and might play a role in accelerated atherogenesis in spondylarthropathies (SpA). Hence, we examined complement activation in SpA, and its relationship to antirheumatic treatment, inflammatory and cardiovascular markers.

METHODS

From PSARA, a prospective observational study, we examined 51 SpA patients (31 psoriatic arthritis (PsA), and 20 ankylosing spondylitis (AS)), starting tumor necrosis factor (TNF) inhibitor alone (n = 25), combined with methotrexate (MTX) (n = 10), or MTX monotherapy (n = 16). Complement activation was determined by the soluble terminal complement complex (sC5b-9), inflammation by erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and endothelial function by finger plethysmography (Endopat) at baseline, after 6 weeks and 6 months of treatment.

RESULTS

SpA patients had sC5b-9 levels at (PsA) or above (AS) the upper limit of the estimated reference range. Median sC5b-9 levels decreased significantly from baseline to 6 weeks, with no significant difference between the AS and PsA group. Notably, a significant reduction in sC5b-9 was observed after administration of TNF inhibitor ± MTX, whereas no significant changes were observed in patients treated with MTX alone. Between 6 weeks and 6 months, sC5b-9 remained stable across all subgroups. Reduction in sC5b-9 was independently related to decreased ESR and CRP, and to increased high density cholesterol and total cholesterol. Reduction in sC5b-9 from baseline to 6 weeks was associated with improved EF in age and gender adjusted analyses.

CONCLUSION

TNF-inhibition, but not MTX monotherapy, led to rapid and sustained reduction of complement activation in SpA. Thus, the observed decrease in cardiovascular morbidity in patients treated with TNF-inhibitors might be partly due to its beneficial effect on complement.

TRIAL REGISTRATION

Clinical Trials (NCT00902005), retrospectively registered on the 14th of May 2009.

Endothelial dysfunction: from the particular to the general. Return to the «Old Paradigm»?

The vascular endothelium is a heterogeneous structure with diverse functions, being an active metabolic system. Endothelial cells mediate inflammatory and immune processes, regulate leukocyte adhesion, permeability and vascular tone, participate in the hemostasis system, stimulate the processes of angiogenesis. Endothelial dysfunction can initiate individual disorders, but more often it is a universal link in the pathogenesis of many diseases. Currently, endothelial dysfunction is presented as an imbalance between the production of vasodilating, angioprotective, antiproliferative factors, on the one hand, and vasoconstrictive, prothrombotic, proliferative factors, on the other hand. The manifestations of endothelial dysfunction, the direction and severity of these changes may vary depending on the disease. The review provides examples of combined endothelial disorders in the most studied and common diseases (essential hypertension, type 2 diabetes, systemic diseases of the connective tissue, atherosclerosis, and malignant tumors). Despite the presence of rare cases of isolated endothelial dysfunction, it can be argued that in the absolute majority of diseases, endothelial dysfunction has combined type of violations. The allocation of individual endothelial disorder spectra, typical for a specific disease, is problematic, due to the universality and nonspecificity of the manifestations of endothelial dysfunction. These conclusions allow us to return to the origins of this problem, considering endothelial dysfunction as a holistic concept, not limited to a certain range of its disorders.

Bilirubin and Endothelial Function

Bilirubin is a fundamental metabolic end product of heme degradation. Despite acting as a cytotoxic metabolite at high concentrations, bilirubin at physiological concentrations has antioxidant effects, such as scavenging reactive oxygen species, leading to a decrease in oxidative stress. Endothelial dysfunction is an early feature of and plays an important role in the development and progression of atherosclerosis, leading to cardiovascular complications. One mechanism of endothelial dysfunction is an increase in oxidative stress, by which the bioavailability of nitric oxide is decreased. Therefore, bilirubin is expected to improve endothelial function, to inhibit the progression of atherosclerosis, and to reduce cardiovascular complications by inactivating oxidative stress through its antioxidant effects. In this review, we will focus on the clinical associations of the antioxidant bilirubin with endothelial function and cardiovascular complications.

Assessment of endothelium-independent vasodilation: from methodology to clinical perspectives

: Vascular response to exogenously administered nitroglycerine, an index of endothelium-independent vasodilation, has been used as a control test for the assessment of endothelium-dependent vasodilation (endothelial function) in humans. However, evidence has been accumulating that not only endothelium-dependent vasodilation but also endothelium-independent vasodilation per se is impaired in individuals with cardiovascular risk factors and cardiovascular disease. Impaired endothelium-independent vasodilation is associated with structural vascular alterations and alterations in vascular smooth muscle cells. Several methods, including assessment of vascular responses to vasoactive agents using angiography in a coronary artery and vascular responses to vasoactive agents using venous occlusion plethysmography and ultrasonography in a peripheral artery, are used to assess endothelium-independent vasodilation in humans. Measurement of endothelium-independent vasodilation is also useful for assessment of atherosclerosis and may be a predictor of future cardiovascular events. In this review, we focus on assessment of endothelium-independent vasodilation from methodology aspects to clinical perspectives.

Spontaneous Coronary Artery Dissection Accompanied with Antiphospholipid Syndrome and Leukemia

We report a rare spontaneous coronary artery dissection (SCAD) case accompanied by antiphospholipid syndrome (APS) and leukemia which was treated successfully with drug-eluted stents (DES) implantation. This young SCAD patient was initially diagnosed of acute myocardial infarction (AMI); however, except for 6 pack-years of smoking, there were no risk factors or family history of coronary artery disease. Subsequently, we screened other clinical status like autoimmune diseases and finally found APS. In general, APS was associated with thromboembolism events, not coronary artery dissection. Our case indicated that SCAD could be a rare manifestation of APS which should draw our attention. In addition, our bail-out therapy acquired the expected effect.

A new method for the assessment of endothelial function with peripheral arterial volume

Background

Currently, many methodological approaches have been developed to assess peripheral endothelial function. However, a development of the noninvasive and automated technique for routinely assessing endothelial function is still required. We evaluated the potential value of a new method to measure peripheral endothelial function with reactive hyperemia peripheral arterial volume (RH-PAV) in patients with chest pain.

Methods

We used a novel oximeter-like probe to detect the peripheral arterial volume (PAV) of the finger and compared it with brachial flow-mediated dilation (FMD) performed in 93 consecutive patients with chest pain. The RH-PAV index was defined as the ratio of the digital pulse volume during reactive hyperemia relative to the baseline.

Results

Ninety-three patients (53 men, 58 ± 5 years) completed the study, and 53 patients demonstrated coronary artery disease (CAD) following scheduled coronary angiography. There was a moderate linear relationship between PAV and FMD (r = 0.69, p < 0.01). Similar to FMD, PAV was more impaired in patients who have more cardiovascular risk factors (CRFs). The subjects with CAD had lower PAV and FMD, compared with those without CAD (1.05 ± 0.23 VS. 1.41 ± 0.37, p < 0.01; 6.7% ± 2.9% VS. 10.4% ± 2.9%, p < 0.01, respectively), and the relationships between FMD and PAV were also significant in both CAD (r = 0.54, p < 0.01) and non-CAD (r = 0.62, p < 0.01) patients.

Conclusions

Endothelial function of digital artery assessed with the novel PAV method demonstrated a profile similar to that of brachial artery measured with FMD. The hyperemia PAV was decreased by factors which were considered to impair endothelial function, suggesting that PAV has the potential to be a novel method to study endothelial function.

[Changes in serum levels of the key factors of angiogenesis in different outcomes of combined injuries in children]

AIM

To study the changes in the key angiogenic factors VEGF-A and angiogenin (ANG) in children with different outcomes of combined injuries.

MATERIAL AND METHODS

Contents of VEGF-A and ANG in blood serum were determined by enzyme immunoassay. The study included 40 patients, 21 boys and 19 girls. Patients were divided into 4 groups according to the outcome of injury: 1 - the recovery or mild residual symptoms; 2 - disabled; 3 - vegetable state; 4 - death. Patients were examined at different times after injury: 1-6 days, 7-11 days, 12-19 and 20-33 days.

RESULTS AND CONCLUSION

In the first days after injury, the content of VEGF-A in patients of 1-3 groups was at the level of the reference group, moreover, in patients of the 3^rd group it was close to the top edge. In group 4, the content of VEGF-A was maximal in the first days after injury and then gradually decreased to the point of death. In groups 1 and 3, the level of VEGF-A increased significantly starting from the 2^nd week while in group 2 this indicator was slightly increased approaching later (up to 33 days of observation) to the upper values in the reference group. In the 3^rd group, the content of VEGF-A reached the plateau on the 19^th day after injury and was higher than the reference data, but lower than in patients of the 1^st group. No correlation between the changes in ANG content at different times after combined injuries and outcome was found. There was a trend towards decreased levels of ANG, especially after 3-4 weeks after injury. The data obtained are important for the control over processes of vascular and tissue reparation after injury and for searching for effective ways of treatment of altered angiogenesis in such patients.

Oral Administration of Glucosamine Improves Vascular Endothelial Function by Modulating Intracellular Redox State

Glucosamine, used to treat osteoarthritis, has been shown to have anti-inflammatory and anti-atherosclerotic effects in experimental studies. A recent cohort study has demonstrated that the use of glucosamine was significantly associated with decreased total mortality. Vascular endothelial function is a potent surrogate marker of atherosclerosis and cardiovascular mortality where oxidative stress could participate. Therefore, we investigated whether glucosamine improves vascular endothelial function and intracellular redox state. We examined the effects of oral glucosamine administration (3000 mg/day) for 4 weeks on flow-mediated vasodilation (FMD) and intraerythrocyte glutathione parameters in 20 volunteers. Nineteen age-matched volunteers served as controls. Glucosamine administration significantly increased FMD (from 7.0 ± 2.3 to 8.7 ± 2.3%, P = 0.022). In the control group, FMD did not change. Glucosamine administration significantly increased intraerythrocyte total glutathione levels (from 212.9 ± 46.2 to 240.6 ± 49.4 μmol/L, P = 0.006), intraerythrocyte reduced form of glutathione (GSH) levels (from 124.7 ± 42.6 to 155.2 ± 47.7 μmol/L; P = 0.004) and intraerythrocyte GSH/oxidized form of glutathione (GSSG) ratios (from 3.18 ± 1.64 to 3.88 ± 1.61, P = 0.04). In the control group, any glutathione parameters did not change. Moreover, a stepwise multivariate analysis revealed percent change of GSH/GSSG is the only independent predictor for those of FMD (standardized β = 0.58, P = 0.007) in the glucosamine group. Glucosamine administration improved FMD in association with amelioration of intraerythrocyte GSH/GSSG ratios. These results suggest that oral glucosamine administration might improve vascular endothelial function by modulating intracellular redox state.

Endothelial and kidney function in women with a history of preeclampsia and healthy parous controls: A case control study

INTRODUCTION

Preeclampsia (PE) is a pregnancy related endothelial disease characterized by hypertension and albuminuria. Postpartum endothelial dysfunction often persists in these women. We postulate that in women with a history of PE reduced endothelial dependent vasodilation coincides with attenuated kidney function, as both reflect endothelial dysfunction.

METHODS

We assessed endothelial and kidney function in women with a history of PE (n=79) and uncomplicated pregnancies (n=49) at least 4years postpartum. Women with hypertension, diabetes or kidney disease prior to pregnancy were excluded. Brachial artery flow mediated dilatation (FMD) was measured and analysed by a custom designed edge-detection and wall-tracking software. We measured albumin and creatinine levels in a 24-h urine sample and calculated glomerular filtration rate (GFR) by CKD-EPI.

RESULTS

Women with a history of PE had lower FMD but comparable GFR and albumin creatinine ratio (ACR) compared with controls. Independent of obstetric history, in both controls and women with a history of PE respectively, GFR (r=0.19, p=0.17 and r=0.12, p=0.29) and albumin creatinine ratio (r=0.07, p=0.62 and r=0.06 p=0.57) did not correlate with FMD.

CONCLUSION

At least 4years after pregnancy, women with a history of PE demonstrated decreased flow mediated dilatation when compared to healthy parous controls. In this study, decreased flow mediated dilation however did not coincide with decreased kidney function.

The relationship between forearm skin speed-resolved perfusion and oxygen saturation, and finger arterial pulsation amplitudes, as indirect measures of endothelial function

OBJECTIVE

Endothelial function is important for regulating peripheral blood flow to meet varying metabolic demands and can be measured indirectly during vascular provocations. In this study, we compared the PAT finger response (EndoPAT) after a 5-minutes arterial occlusion to that from forearm skin comprehensive microcirculation analysis (EPOS).

METHODS

Measurements in 16 subjects with varying cardiovascular risk factors were carried out concurrently with both methods during arterial occlusion, while forearm skin was also evaluated during local heating.

RESULTS

Peak values for EPOS skin Perf_conv and speed-resolved total perfusion after the release of the occlusion were significantly correlated to the EndoPAT RHI (ρ = .68, P = .007 and ρ = .60, P = .025, respectively), mainly due to high-speed blood flow. During local heating, EPOS skin oxygen saturation, SO2, was significantly correlated to RHI (ρ = .62, P = .043). This indicates that SO2 may have diagnostic value regarding endothelial function.

CONCLUSIONS

We have demonstrated for the first time a significant relationship between forearm skin microcirculatory perfusion and oxygen saturation and finger PAT. Both local heating and reactive hyperemia are useful skin provocations. Further studies are needed to understand the precise regulation mechanisms of blood flow and oxygenation during these tests.

Hypotonic contrast media is more toxic than isotonic contrast media on endothelial cells in vivo and in vitro

The aim of the current study was to investigate the cytotoxic effects of hypotonic (iopamidol) and isotonic (iodixanol) contract media (CMs) in vitro and in vivo. A total of 60 Wistar rats were included and were randomly divided into three groups (20 rats per group). Iodixanol (4 g iodine/kg), iopamidol (4 g iodine/kg) or equal volume of normal saline was injected via tail vein. HUVEC and H5V cell viability was determined by Cell Counting Kit‑8 agents. Western blotting was performed to detect ATP‑binding cassette subfamily G member 1 (ABCG1) expression. For histological analysis, hematoxylin and eosin staining was performed. Plasma endothelin, von Willebrand factor, tissue type plasminogen activator, plasminogen activator inhibitor, D‑Dimer, fibrinogen, anti‑thrombin III, plasminogen and nitric oxide synthase (NOS) were measured by using ELISA. Both iopamidol and iodixanol treatments deceased cell viability and increased apoptosis of HUVEC and H5V cells, along with downregulated NOS and ABCG1. The injection of iopamidol or iodixanol into rats changed the endothelium‑related plasma levels of biomarkers, including endothelin, von Willebrand factor, tissue type plasminogen activator, plasminogen activator inhibitor, D‑Dimer, fibrinogen and anti‑thrombin III. However, endothelia isolated from rat abdominal aorta in the iodixanol group retained their normal structure, whereas endothelial structure in the iopamidol group was injured and disrupted. The findings in the present study suggested that both hypotonic and isotonic CMs may lead to endothelial dysfunction and thrombin and fibrinolytic system disorder. However, hypotonic CMs may be more toxic than isotonic CMs. Therefore, additional cautions should be taken when selecting hypotonic CMs and their dosages during cardioangiography.

A Randomized Trial of Vitamin D Supplementation on Vascular Function in CKD

Vitamin D deficiency associates with mortality in patients with CKD, and vitamin D supplementation might mitigate cardiovascular disease risk in CKD. In this randomized, double-blind, placebo-controlled trial, we investigated the effect of cholecalciferol supplementation on vascular function in 120 patients of either sex, aged 18-70 years, with nondiabetic CKD stage 3-4 and vitamin D deficiency (serum 25-hydroxyvitamin D ≤20 ng/ml). We randomized patients using a 1:1 ratio to receive either two directly observed oral doses of cholecalciferol (300,000 IU) or matching placebo at baseline and 8 weeks. The primary outcome was change in endothelium-dependent brachial artery flow-mediated dilation at 16 weeks. Secondary outcome measures included changes in pulse wave velocity and circulating biomarkers. Cholecalciferol supplementation significantly increased endothelium-dependent brachial artery flow-mediated dilation at 16 weeks, whereas placebo did not (between-group difference in mean change: 5.49%; 95% confidence interval, 4.34% to 6.64%; P<0.001). Intervention also led to significant favorable changes in pulse wave velocity and circulating IL-6 levels. Thus, in nondiabetic patients with stage 3-4 CKD and vitamin D deficiency, vitamin D supplementation may improve vascular function. This study is registered with the Clinical Trials Registry of India (no.: CTRI/2013/05/003648).

Claimed effects, outcome variables and methods of measurement for health claims proposed under European Community Regulation 1924/2006 in the framework of protection against oxidative damage and cardiovascular health

BACKGROUND AND AIMS

The high number of negative opinions from the European Food Safety Authority (EFSA) to the requests for authorization of health claims is largely due to the design of human intervention studies, including the inappropriate choice of outcome variables (OVs) and of their methods of measurement (MMs). The present manuscript reports the results of an investigation aimed to collect, collate and critically analyse the information in relation to claimed effects, OVs and MMs, in the context of protection against oxidative damage and cardiovascular health compliant with Regulation 1924/2006.

METHODS AND RESULTS

Claimed effects, OVs and the related MMs were collected from EFSA Guidance documents and applications for authorization of health claims under Articles 13.5 and 14. The OVs and their MMs were evaluated only if the claimed effect was sufficiently defined and was considered beneficial by EFSA. The collection, collation and critical analysis of the relevant scientific literature consisted in the definition of the keywords, the PubMed search strategies and the creation of databases of references. The critical analysis of the OVs and their MMs was performed on the basis of the literature review and was aimed at defining the appropriateness of OVs and MMs in the context of the specific claimed effects.

CONCLUSIONS

The information provided in this document could serve to EFSA for the development of further guidance on the scientific requirements for health claims, as well as to the stakeholders for the proper design of human intervention studies aimed to substantiate such health claims.

Molecular effects of exercise training in patients with cardiovascular disease: focus on skeletal muscle, endothelium, and myocardium

For decades, we have known that exercise training exerts beneficial effects on the human body, and clear evidence is available that a higher fitness level is associated with a lower incidence of suffering premature cardiovascular death. Despite this knowledge, it took some time to also incorporate physical exercise training into the treatment plan for patients with cardiovascular disease (CVD). In recent years, in addition to continuous exercise training, further training modalities such as high-intensity interval training and pyramid training have been introduced for coronary artery disease patients. The beneficial effect for patients with CVD is clearly documented, and during the last years, we have also started to understand the molecular mechanisms occurring in the skeletal muscle (limb muscle and diaphragm) and endothelium, two systems contributing to exercise intolerance in these patients. In the present review, we describe the effects of the different training modalities in CVD and summarize the molecular effects mainly in the skeletal muscle and cardiovascular system.

Lower urinary tract symptoms/benign prostatic hypertrophy and vascular function: Role of the nitric oxide-phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate pathway

It is well known that there is an association of lower urinary tract symptoms/benign prostatic hypertrophy with cardiovascular disease, suggesting that lower urinary tract symptoms/benign prostatic hypertrophy is a risk factor for cardiovascular events. Vascular function, including endothelial function and vascular smooth muscle function, is involved in the pathogenesis, maintenance and development of atherosclerosis, leading to cardiovascular events. Vascular dysfunction per se should also contribute to lower urinary tract symptoms/benign prostatic hypertrophy. Both lower urinary tract symptoms/benign prostatic hypertrophy and vascular dysfunction have cardiovascular risk factors, such as hypertension, dyslipidemia, diabetes mellitus, aging, obesity and smoking. Inactivation of the phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate-nitric oxide pathway causes lower urinary tract symptoms/benign prostatic hypertrophy through an enhancement of sympathetic nervous activity, endothelial dysfunction, increase in Rho-associated kinase activity and vasoconstriction, and decrease in blood flow of pelvic viscera. Both endogenous nitric oxide and exogenous nitric oxide act as vasodilators on vascular smooth muscle cells through an increase in the content of cyclic guanosine 3',5'-monophosphate, which is inactivated by phosphodiesterase type 5. In a clinical setting, phosphodiesterase type 5 inhibitors are widely used in patients with lower urinary tract symptoms/benign prostatic hypertrophy. Phosphodiesterase type 5 inhibitors might have beneficial effects on vascular function through not only inhibition of cyclic guanosine 3',5'-monophosphate degradation, but also increases in testosterone levels and nitric oxide bioavailability, increase in the number and improvement of the function of endothelial progenitor cells, and decrease in insulin resistance. In the present review, the relationships between lower urinary tract symptoms/benign prostatic hypertrophy, the phosphodiesterase type 5-nitric oxide-cyclic guanosine 3',5'-monophosphate pathway, vascular function and cardiovascular outcomes are examined.

Systemic effects of controlled exposure to diesel exhaust: a meta-analysis from randomized controlled trials

INTRODUCTION

Ambient air pollution is associated with adverse cardiovascular events. This meta-analysis aimed to investigate the short-term association between air pollution and cardiovascular effects on healthy volunteers.

METHODS

We searched databases to identify randomized trials with controlled human exposures to either of two models for studying ambient particulate matter: diesel-exhaust or concentrated ambient particles. Estimates of size effect were performed using standardized mean difference (SMD). Heterogeneity was assessed with I₂ statistics. Outcomes were vascular function estimated by forearm blood flow (FBF), blood pressure, heart rate, and blood analysis.

RESULTS

Database searches yielded 17 articles (n = 342) with sufficient information for meta-analyses. High levels of heterogeneity for the some outcomes were analyzed using random-effects model. The pooled effect estimate showed that short-term exposure to air pollution impaired FBF response from 2.7 to 2.5 mL/100 mL tissue/min (SMD 0.404; p = .006). There was an increase in 5000 platelet/mm³ following pollution exposure (SMD 0.390; p = .050) but no significant differences for other outcomes.

CONCLUSION

Controlled human exposures to air pollution are associated with the surrogates of vascular dysfunction and increase in platelet count, which might be related to adverse cardiovascular events. Given the worldwide prevalence of exposure to air pollution, these findings are relevant for public health. KEY MESSAGES Controlled exposure to air pollution impairs vasomotor response, which is a surrogate for adverse cardiovascular events. This is the first meta-analysis from randomized clinical trials showing short-term association between air pollution and cardiovascular effects on healthy volunteers. Given the worldwide prevalence of exposure to air pollution, this finding is important for public health.

Vascular function in asthmatic children and adolescents

Background

Epidemiological studies have demonstrated an increased incidence of cardiovascular events in patients with bronchial asthma, but little is known about the relationship between asthma and vascular function. The purpose of this study was to evaluate endothelial function and arterial stiffness in children and adolescents with asthma.

Methods

A cross-sectional controlled study was designed. Measurements of endothelial function and arterial stiffness in asthmatic (13.6 ± 0.6 years) and control groups (14.9 ± 0.7 years) were taken by the non-invasive peripheral arterial tonometry (EndoPAT2000) determined by using the natural logarithm of the reactive hyperemia index (LnRHI) and the augmentation index (AIx@75%), respectively. Patients with asthma were also administered two questionnaires to evaluate asthma control and quality of life. Exercise functional capacity was evaluated using the Shuttle Walking Test (SWT). Only male participants were included in the present study.

Results

LnRHI and the walked distance during the SWT were similar between groups (p = 0.23 and p = 0.50, respectively). AIx@75% was significantly higher in the asthmatic group (-7.75 ± 1.7) compared to the control group (-15.25 ± 1.8), p < 0.04. In the control group, the LnRHI correlated positively with baseline systolic blood pressure (r = 0.53, p = 0.02) and mean arterial pressure (r = 0.50, p = 0.03), age (r = 0.61, p = 0.007), weight (r = 0.63, p = 0.004) and height (r = 0.56, p = 0.015). Besides that LnRHI correlated with FVC (r = 0.69, p = 0.002), FEV₁, (r = 0.53, p = 0.03) and negatively with Tiffeneau index (FEV₁/FVC%, r = −0.49 p = 0.04). The LnRHI of the asthmatic group did not correlate with the different variables evaluated.

Conclusion

The increased AIx@75% without changes in LnRHI in asthmatic patients could mean that an early detection of vascular impairment may precede endothelial dysfunction, and that different mechanisms may contribute to the pathogenesis and progression of cardiovascular events in this population. A large prospective and randomized controlled study should be done to evaluate the physiopathological mechanisms underlying the association between arterial stiffness and asthma.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-016-0488-3) contains supplementary material, which is available to authorized users.

A Single Session of Neuromuscular Electrical Stimulation Enhances Vascular Endothelial Function and Peripheral Blood Circulation in Patients With Acute Myocardial Infarction

This study aimed to investigate whether a single session of neuromuscular electrical stimulation (NMES) can enhance vascular endothelial function and peripheral blood circulation in patients with acute myocardial infarction (AMI). Thirty-four male patients with AMI were alternately assigned to 2 groups, and received NMES with muscle contraction (NMES group, n = 17) or without muscle contraction (control group, n = 17) after admission. NMES was performed for quadriceps and gastrocnemius muscles of both legs for 30 minutes. We measured systolic blood pressure as a parameter of cardiovascular responses and the low-frequency component of blood pressure variability as an index of sympathetic activity. Reactive hyperemia peripheral arterial tonometry (RH-PAT) index and transcutaneous oxygen pressure in foot (Foot-tcPO₂) were also measured as parameters of vascular endothelial function and peripheral blood circulation, respectively. All patients completed the study without severe adverse events. Systolic blood pressure and the low-frequency component increased significantly during the NMES session in both groups (P < 0.01 and P < 0.05, respectively). However, elevation from systolic blood pressure at rest was < 10 mmHg in both groups. In the NMES group, the RH-PAT index and Foot-tcPO₂ increased significantly after NMES (P < 0.05 and P < 0.001, respectively). No significant changes were observed in these parameters throughout the session in the control group. In conclusion, a single session of NMES with muscle contraction enhanced vascular endothelial function, leading to improvement in peripheral blood circulation without inducing excessive cardiovascular and autonomic responses in patients with AMI (UMIN000014196).

Migraine and endothelial function: The HUNT3 Study

Background

Reduced endothelial function is associated with elevated risk of cardiovascular disease, but evidence on the association between migraine and endothelial function is conflicting. The aim of this population-based study was to examine the relationship between flow-mediated dilatation (FMD) and migraine with aura, migraine without aura and tension-type headache.

Methods

In the third Nord-Trøndelag Healthy Study (HUNT3) FMD was measured by ultrasound during reactive hyperaemia of the brachial artery in a sample of 4739 healthy adult participants, 3929 of whom answered headache questions. The cross-sectional association between different headache diagnoses and FMD was evaluated by logistic regression, using a categorical approach.

Results

Mean FMD did not differ between the headache groups and headache-free controls. In multi-adjusted analyses, no consistent association was found between FMD quintiles and headache groups.

Conclusions

There was no relationship between FMD and migraine or other headache diagnoses in this large cross-sectional study of otherwise healthy respondents including freedom from pulmonary and cardiovascular diseases.