Blood pressure in relation to neurogenic, inflammatory and endothelial dysfunction biomarkers in patients with treated essential arterial hypertension

Cardiovascular/Stroke Risk Assessment in Patients with Erectile Dysfunction-A Role of Carotid Wall Arterial Imaging and Plaque Tissue Characterization Using Artificial Intelligence Paradigm: A Narrative Review

PURPOSE

The role of erectile dysfunction (ED) has recently shown an association with the risk of stroke and coronary heart disease (CHD) via the atherosclerotic pathway. Cardiovascular disease (CVD)/stroke risk has been widely understood with the help of carotid artery disease (CTAD), a surrogate biomarker for CHD. The proposed study emphasizes artificial intelligence-based frameworks such as machine learning (ML) and deep learning (DL) that can accurately predict the severity of CVD/stroke risk using carotid wall arterial imaging in ED patients.

METHODS

Using the PRISMA model, 231 of the best studies were selected. The proposed study mainly consists of two components: (i) the pathophysiology of ED and its link with coronary artery disease (COAD) and CHD in the ED framework and (ii) the ultrasonic-image morphological changes in the carotid arterial walls by quantifying the wall parameters and the characterization of the wall tissue by adapting the ML/DL-based methods, both for the prediction of the severity of CVD risk. The proposed study analyzes the hypothesis that ML/DL can lead to an accurate and early diagnosis of the CVD/stroke risk in ED patients. Our finding suggests that the routine ED patient practice can be amended for ML/DL-based CVD/stroke risk assessment using carotid wall arterial imaging leading to fast, reliable, and accurate CVD/stroke risk stratification.

SUMMARY

We conclude that ML and DL methods are very powerful tools for the characterization of CVD/stroke in patients with varying ED conditions. We anticipate a rapid growth of these tools for early and better CVD/stroke risk management in ED patients.

Spirulina maxima Decreases Endothelial Damage and Oxidative Stress Indicators in Patients with Systemic Arterial Hypertension: Results from Exploratory Controlled Clinical Trial

(1) Background: Spirulina (Arthrospira) maxima has shown beneficial effects such as being anti-dyslipidemic, antiviral, antioxidant and antihypertensive. However, there are few and limited clinical studies. (2) Methods: a prospective, randomized, parallel pilot study of 4.5 g administration of Spirulinamaxima or placebo for 12 weeks in 16 patients with systemic arterial hypertension (SAH) undergoing treatment with angiotensin-converting enzyme (ACE) inhibitors was performed to assess the effects on endothelial damage and oxidative stress indicators. The blood levels of sICAM-1, sVCAM-1, endothelin-1, and sE-selectin were quantified; the activities of catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase and concentrations of reduced glutathione, oxidized glutathione, and thiobarbituric acid reactive substances, were also quantified before and after the treatment period. (3) Results: There were statistically significant (p < 0.05) decreases in systolic blood pressure, sVCAM-1, sE-selectin and endothelin-1 levels, and increases in glutathione peroxidase activity and oxidized glutathione levels. (4) Conclusion: The effects found in the present study agree with antihypertensive and antioxidant effects previously reported for Spirulina maxima. However, this is the first report about the effects on indicators of endothelial damage. More research in this field is necessary to gain an insight into the effects of Spirulina on these indicators.

Arterial stiffness and central arterial wave reflection are associated with serum uric acid, total bilirubin, and neutrophil-to-lymphocyte ratio in patients with coronary artery disease

OBJECTIVE

Total bilirubin (TB) was recently recognized as an endogenous anti-inflammatory and anti-oxidant molecule. Uric acid (UA) takes part in cardiovascular diseases by inducing oxidative stress, inflammation, and endothelial dysfunction. We assessed the relationship between serum TB levels, serum UA levels, and inflammatory status assessed by neutrophil-to-lymphocyte ratio (N/L) and arterial stiffness and arterial wave reflection in patients with a clinical diagnosis of coronary artery disease (CAD).

METHODS

We included 145 consecutive patients admitted with stable angina pectoris (SAP) or acute coronary syndrome (ACS). Blood samples were drawn at admission for complete blood count and biochemistry. Non-invasive pulse waveform analysis for the determination of augmentation index (AIx) and carotid-femoral pulse wave velocity (PWV) measurements were performed with the commercially available SphygmoCor system.

RESULTS

When patients were divided into tertiles of PWV and AIx, median N/L and median serum UA levels were the highest and mean TB levels were the lowest in the third tertile (p<0.001 for all). AIx and PWV were positively associated with serum UA and N/L and negatively associated with serum TB levels (p<0.001 for all). After adjustments for age, gender, heart rate, systolic blood pressure, and presence of diabetes, significant correlations persisted for N/L, UA, and TB in ACS patients (p<0.05). In the SAP group, TB was significantly negatively correlated with AIx and PWV, and UA was significantly positively correlated with PWV (p<0.05).

CONCLUSION

N/L ratio and serum UA and TB levels might be used to risk-stratify patients with respect to arterial stiffness in CAD patients, especially in the presence of ACS.

Is elevated norepinephrine an etiological factor in some cases of schizophrenia?

A number of hypotheses have been put forth regarding the etiology of schizophrenia, including the dopamine hypothesis, NMDA receptor hypofunction hypothesis, and others. A lesser known theory is that elevated noradrenergic signaling plays a causative role in the disease. This paper briefly re-examines the merits of this hypothesis, including as it relates to some recently published studies. Several lines of evidence are investigated, including: endogenous level studies of norepinephrine (NE); modulation of the disease by noradrenergic drugs; association of the disease with bipolar disorder and hypertension, since these latter two conditions may involve elevated NE transmission; and effects of psychological stress on the disease, since stress can produce elevated release of NE. For many of these lines of evidence, their relationship with prepulse inhibition of startle is examined. A number of these studies support the hypothesis, and several suggest that elevated NE signaling plays a particularly prominent role in the paranoid subtype of schizophrenia. If the hypothesis is correct for some persons, conventional pharmaceutical treatment options, such as use of atypical antipsychotics (which may themselves modulate noradrenergic signaling), may be improved if selective NE transmission modulating agents are added to or even substituted for these conventional drugs.

Autonomic and hemodynamic origins of pre-hypertension: central role of heredity

OBJECTIVES

The purpose of this study is to better understand the origins and progression of pre-hypertension.

BACKGROUND

Pre-hypertension is a risk factor for progression to hypertension, cardiovascular disease, and increased mortality. We used a cross-sectional twin study design to examine the role of heredity in likely pathophysiological events (autonomic or hemodynamic) in pre-hypertension.

METHODS

Eight hundred twelve individuals (337 normotensive, 340 pre-hypertensive, 135 hypertensive) were evaluated in a sample of twin pairs, their siblings, and other family members. They underwent noninvasive hemodynamic, autonomic, and biochemical testing, as well as estimates of trait heritability (the percentage of trait variance accounted for by heredity) and pleiotropy (the genetic covariance or shared genetic determination of traits) by variance components.

RESULTS

In the hemodynamic realm, an elevation of cardiac contractility prompted increased stroke volume, in turn increasing cardiac output, which elevated blood pressure into the pre-hypertension range. Autonomic monitoring detected an elevation of norepinephrine secretion plus a decline in cardiac parasympathetic tone. Twin pair variance components documented substantial heritability as well as joint genetic determination for blood pressure and the contributory autonomic and hemodynamic traits. Genetic variation at a pathway locus also indicated pleiotropic effects on contractility and blood pressure.

CONCLUSIONS

Elevated blood pressure in pre-hypertension results from increased cardiac output, driven by contractility as well as heart rate, which may reflect both diminished parasympathetic and increased sympathetic tone. In the face of increased cardiac output, systemic vascular resistance fails to decline homeostatically. Such traits display substantial heritability and shared genetic determination, although by loci not yet elucidated. These findings clarify the role of heredity in the origin of pre-hypertension and its autonomic and hemodynamic pathogenesis. The results also establish pathways that suggest new therapeutic targets for pre-hypertension, or approaches to its prevention.

Effect of carvedilol and nebivolol on oxidative stress-related parameters and endothelial function in patients with essential hypertension

Oxidative stress and endothelial dysfunction have been associated with essential hypertension (EH) mechanisms. The purpose of this study was to evaluate the effect of carvedilol and nebivolol on the oxidative stress-related parameters and endothelial function in patients with EH. The studied population included 57 patients, either sex, between 30 and 75 years of age, with mild-to-moderate EH complications. Participants were randomized to receive either carvedilol (12.5 mg) (n = 23) or nebivolol (5 mg) (n = 21) for 12 weeks. Measurements included; 24-hr ambulatory blood pressure (BP), flow-mediated dilatation, levels of nitric oxide estimated as nitrite - a nitric oxide metabolite ( NO₂) - in plasma, and oxidative stress-related parameters in plasma and erythrocyte. EH patients who were treated with nebivolol or carvedilol showed systolic BP reductions of 17.4 and 19.9 mmHg, respectively, compared with baseline values (p < 0.01). Diastolic BP was reduced by 13.7 and 12.8 mmHg after the treatment with ebivolol and carvedilol, respectively (p < 0.01) (fig. 2B). Nebivolol and carvedilol showed 7.3% and 8.1% higher endothelium-dependent dilatation in relation to baseline values (p < 0.05). Ferric-reducing ability of plasma (FRAP) and reduced glutathione/oxidized glutathione (GSSH) ratio showed 31.5% and 29.6% higher levels in the carvedilol group compared with basal values; however, nebivolol-treated patients did not show significant differences after treatment. On the other hand, the NO₂ plasma concentration was not modified by the administration of carvedilol. However, nebivolol enhanced these levels in 62.1% after the treatment. In conclusion, this study demonstrated the antihypertensive effect of both beta-blockers. However, carvedilol could mediate these effects by an increase in antioxidant capacity and nebivolol through the raise in NO₂ concentration. Further studies are needed to determine the molecular mechanism of these effects.

Endoplasmic reticulum stress is involved in cardiac damage and vascular endothelial dysfunction in hypertensive mice

OBJECTIVE

Cardiac damage and vascular dysfunction are major causes of morbidity and mortality in hypertension. In the present study, we explored the beneficial therapeutic effect of endoplasmic reticulum (ER) stress inhibition on cardiac damage and vascular dysfunction in hypertension.

METHODS AND RESULTS

Mice were infused with angiotensin II (400 ng/kg per minute) with or without ER stress inhibitors (taurine-conjugated ursodeoxycholic acid and 4-phenylbutyric acid) for 2 weeks. Mice infused with angiotensin II displayed an increase in blood pressure, cardiac hypertrophy and fibrosis associated with enhanced collagen I content, transforming growth factor-β1 (TGF-β1) activity, and ER stress markers, which were blunted after ER stress inhibition. Hypertension induced ER stress in aorta and mesenteric resistance arteries (MRA), enhanced TGF-β1 activity in aorta but not in MRA, and reduced endothelial NO synthase phosphorylation and endothelium-dependent relaxation (EDR) in aorta and MRA. The inhibition of ER stress significantly reduced TGF-β1 activity, enhanced endothelial NO synthase phosphorylation, and improved EDR. The inhibition of TGF-β1 pathway improved EDR in aorta but not in MRA, whereas the reduction in reactive oxygen species levels ameliorated EDR in MRA only. Infusion of tunicamycin in control mice induced ER stress in aorta and MRA, and reduced EDR by a TGF-β1-dependent mechanism in aorta and reactive oxygen species-dependent mechanism in MRA.

CONCLUSIONS

ER stress inhibition reduces cardiac damage and improves vascular function in hypertension. Therefore, ER stress could be a potential target for cardiovascular diseases.