Drug Treatment of Hypertension: Focus on Vascular Health

Food-Derived Up-Regulators and Activators of Angiotensin Converting Enzyme 2: A Review

Angiotensin-converting enzyme 2 (ACE2) is a key enzyme in the renin-angiotensin system (RAS), also serving as an amino acid transporter and a receptor for certain coronaviruses. Its primary role is to protect the cardiovascular system via the ACE2/Ang (1-7)/MasR cascade. Given the critical roles of ACE2 in regulating numerous physiological functions, molecules that can upregulate or activate ACE2 show vast therapeutic value. There are only a few ACE2 activators that have been reported, a wide range of molecules, including food-derived compounds, have been reported as ACE2 up-regulators. Effective doses of bioactive peptides range from 10 to 50 mg/kg body weight (BW)/day when orally administered for 1 to 7 weeks. Protein hydrolysates require higher doses at 1000 mg/kg BW/day for 20 days. Phytochemicals and vitamins are effective at doses typically ranging from 10 to 200 mg/kg BW/day for 3 days to 6 months, while Traditional Chinese Medicine requires doses of 1.25 to 12.96 g/kg BW/day for 4 to 8 weeks. ACE2 activation is linked to its hinge-bending region, while upregulation involves various signaling pathways, transcription factors, and epigenetic modulators. Future studies are expected to explore novel roles of ACE2 activators or up-regulators in disease treatments and translate the discovery to bedside applications.

The Melatonin Derivative ITH13001 Prevents Hypertension and Cardiovascular Alterations in Angiotensin II-Infused Mice

Inflammatory mechanisms and oxidative stress seem to contribute to the pathogenesis of hypertension. ITH13001 is a melatonin-phenyl-acrylate hybrid that moderately induces the antioxidant transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) and has a potent oxidant scavenging effect compared with other derivatives of its family. Here we investigated the effect of ITH13001 on hypertension and the associated cardiovascular alterations. Angiotensin II (AngII)-infused mice were treated with ITH13001 (1 mg/kg per day, i.p.) for 2 weeks. The ITH13001 treatment prevented: 1) the development of hypertension, cardiac hypertrophy, and increased collagen and B-type natriuretic peptide (Bnp) expression in the heart; 2) the reduction of elasticity, incremental distensibility, fenestrae area, intraluminal diameter, and endothelial cell number in mesenteric resistance arteries (MRA); 3) the endothelial dysfunction in aorta and MRA; 4) the plasma and cardiovascular oxidative stress and the reduced aortic nitric oxide (NO) bioavailability; 5) the increased cardiac levels of the cytokines interleukin (IL)-1β, IL-6, and C-C motif chemokine ligand 2 (Ccl2), the T cell marker cluster of differentiation 3 (Cd3), the inflammasome NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3), the proinflammatory enzymes inducible nitric oxide synthase (iNOS) and COX-2, the toll-like receptor 4 (TLR4) adapter protein myeloid differentiation primary response 88 (MyD88), and the nuclear factor kappa B (NF-κB) subunit p65; 6) the greater aortic expression of the cytokines tumor necrosis factor alpha (Tnf-α), Ccl2 and IL-6, Cd3, iNOS, MyD88, and NLRP3. Although ITH13001 increased nuclear Nrf2 levels and heme oxygenase 1 (HO-1) expression in vascular smooth muscle cells, both cardiac and vascular Nrf2, Ho-1, and NADPH quinone dehydrogenase 1 (Nqo1) levels remained unmodified irrespective of AngII infusion. Summarizing, ITH13001 improved hypertension-associated cardiovascular alterations independently of Nrf2 pathway activation, likely due to its direct antioxidant and anti-inflammatory properties. Therefore, ITH13001 could be a useful therapeutic strategy in patients with resistant hypertension. SIGNIFICANCE STATEMENT: Despite the existing therapeutic arsenal, only half of the patients treated for hypertension have adequately controlled blood pressure; therefore, the search for new compounds to control this pathology and the associated damage to end-target organs (cerebral, cardiac, vascular, renal) is of particular interest. The present study demonstrates that a new melatonin derivative, ITH13001, prevents hypertension development and the associated cardiovascular alterations due to its antioxidant and anti-inflammatory properties, making this compound a potential candidate for treatment of resistant hypertensive patients.

Pharmacokinetics and Drug-Drug Interaction of Allisartan Isoproxil and Indapamide Sustained-Release Formulation

Allisartan isoproxil (AI) is an angiotensin II type 1 receptor blocker and be converted into the active substance EXP3174 in vivo. We evaluated the drug-drug interactions of AI and an indapamide sustained-release (Ind SR) preparation, as well as the pharmacokinetic characteristics and safety of AI and Ind SR in healthy subjects. The trial was set up in 6 sequences and 3 cycles, and each cycle contained a 7-day washout period. Subjects received 3 different trial drugs (A, AI; B, Ind SR; C, AI + Ind SR) during 3 different cycles. Twenty-four subjects were enrolled in the clinical trial. Of these, 22 completed the study, 2 subjects dropped out due to adverse events (AEs). For subjects given AI alone or combined with Ind SR, the pharmacogenetic parameters Cmax and the geometric mean ratio of steady state (combined/single) of EXP3174 was 130%. The geometric mean ratio of area under the concentration-time curve over the dosing interval at steady state (combined/single use) was 144.5%. Therefore, the combination of Ind SR had an impact on the pharmacokinetics of AI. Then, the results indicated that the AI combination had no effect on the pharmacokinetics of Ind SR. Serious AEs did not occur. The AEs in this clinical trial were the same as those for AI and Ind SR. Combined administration resulted in 2 cases (2 subjects) of Grade 3 hypotension and 1 case of Grade 3 hypotension with AI alone. Considering that this trial included healthy volunteers, the risk of hypotension was expected to be manageable.

Comparative effect of antihypertensive drugs in improving arterial stiffness in adults with hypertension (RIGIPREV study). A network meta-analysis

Aims: To synthesize and evaluate the available scientific evidence on the efficacy of antihypertensive drugs on arterial stiffness in patients with hypertension by using a network meta-analysis approach. Methods: A systematic search of the MEDLINE (via PubMed), Scopus, and Web of Science databases was conducted to identify experimental studies addressing the effect of different antihypertensive drugs on arterial stiffness parameters (pulse wave velocity [PWV] and augmentation index [AIx]) in adults with hypertension. Comparative evaluation of the effect of antihypertensive drugs was performed by conducting a standard pairwise meta-analysis and a network meta-analysis for direct and indirect comparisons between antihypertensive drugs and placebo/other antihypertensive drugs. Analyses were performed including studies of any duration and only studies longer than 6 months length. Results: Seventy-six studies were included in the main analysis and considering only studies longer than 6 months length, thiazide diuretics, ACEIs, ARBs, the ACEI/ARB combination, the ACEI/CCB combination, and the ARB/CCB combination showed a higher effect on reducing PWV, and ACEIs and ARBs on reducing AIx. Conclusion: Our research provides evidence that antihypertensive medications are an effective way to treat arterial stiffness in adults with hypertension. Based on our findings, patients with hypertension who have greater levels of arterial stiffness may benefit from using thiazide diuretics, ACEIs, ARBs, the ACEI/ARB combination, the ACEI/CCB combination, and the ARB/CCB combination. Systematic Review Registration: PROSPERO (CRD42021276360).

Endothelial dysfunction as a factor leading to arterial hypertension

Hypertension remains the main cause of cardiovascular complications leading to increased mortality. The discoveries of recent years underline the important role of endothelial dysfunction (ED) in initiating the development of arterial hypertension. The endothelium lines the interior of the entire vascular system in the body and acts as a physical barrier between blood and tissues. Substances and mediators produced by the endothelium exhibit antithrombotic and anti-inflammatory properties. Oxidative stress and inflammation are conditions that damage the endothelium and shift endothelial function from vasoprotective to vasoconstrictive, prothrombotic, and pro-apoptotic functions. A dysfunctional endothelium contributes to the development of hypertension and further cardiovascular complications. Reduced nitric oxide (NO) bioavailability plays an essential role in the pathophysiology of ED-associated hypertension. New technologies provide tools to identify pathological changes in the structure and function of the endothelium. Endothelial dysfunction (ED) contributes to the development of arterial hypertension and should be considered in therapeutic strategies for children with hypertension.

Vascular stiffness and healthy arterial aging in older patients with optimal blood pressure

INTRODUCTION

Pulse wave velocity is used to diagnose central arterial stiffness (CAS) and quantify healthy vascular aging (HVA).

OBJECTIVE

To evaluate the CAS and HVA in elderly patients with systemic blood pressure levels classified as optimal/normal.

METHODS

A total of 102 patients without comorbidities and with systolic pressure (SP) < 120 mmHg and diastolic pressure (DP) < 80 mmHg were selected from the EVOPIU database (Pulse Wave Velocity of Elderly Individuals in an Urban area of Brazil). The carotid-femoral pulse wave velocity (c-fPWV) and the central and peripheral pressures were evaluated in all patients. The patients were divided into four groups: G1: (n = 19, with c-fPWV < 7.6 m/s, without medication), G2 (n = 26, c-fPWV ≥ 7.6 m/s; without medication), G3 (n = 25, c-fPWV < 7.6 m/s with antihypertensive medication), and G4 (n = 32, c-fPWV ≥ 7.6 m/s with antihypertensive medication).

RESULTS

In our sample, 56.7% of patients had c-fPWV ≥ 7.6 m/s. The central systolic pressure in G1 [99 (10) mmHg] was lower than that found in the other three groups [vs. 112 (14) mmHg, 111 (15), 112 (20) mmHg; P < 0.05)].

CONCLUSION

Older people with optimal arterial blood pressure do not necessarily have HVA and could have c-fPWV values close to the limits established for CAS diagnosis.

Predicting 1-year mortality of patients with diabetes mellitus in Kazakhstan based on administrative health data using machine learning

Diabetes mellitus (DM) affects the quality of life and leads to disability, high morbidity, and premature mortality. DM is a risk factor for cardiovascular, neurological, and renal diseases, and places a major burden on healthcare systems globally. Predicting the one-year mortality of patients with DM can considerably help clinicians tailor treatments to patients at risk. In this study, we aimed to show the feasibility of predicting the one-year mortality of DM patients based on administrative health data. We use clinical data for 472,950 patients that were admitted to hospitals across Kazakhstan between mid-2014 to December 2019 and were diagnosed with DM. The data was divided into four yearly-specific cohorts (2016-, 2017-, 2018-, and 2019-cohorts) to predict mortality within a specific year based on clinical and demographic information collected up to the end of the preceding year. We then develop a comprehensive machine learning platform to construct a predictive model of one-year mortality for each year-specific cohort. In particular, the study implements and compares the performance of nine classification rules for predicting the one-year mortality of DM patients. The results show that gradient-boosting ensemble learning methods perform better than other algorithms across all year-specific cohorts while achieving an area under the curve (AUC) between 0.78 and 0.80 on independent test sets. The feature importance analysis conducted by calculating SHAP (SHapley Additive exPlanations) values shows that age, duration of diabetes, hypertension, and sex are the top four most important features for predicting one-year mortality. In conclusion, the results show that it is possible to use machine learning to build accurate predictive models of one-year mortality for DM patients based on administrative health data. In the future, integrating this information with laboratory data or patients' medical history could potentially boost the performance of the predictive models.

Rigidez vascular e envelhecimento arterial saudável em pacientes idosos com pressão arterial ideal

RESUMO Introdução: A velocidade da onda de pulso é usada para diagnosticar a rigidez arterial central (RAC) e quantificar o envelhecimento vascular saudável (EVS). Objetivo: Avaliar a RAC e o EVS em pacientes idosos com níveis pressóricos sistêmicos classificados como ideais/normais. Métodos: Um total de 102 pacientes sem comorbidades e com pressão sistólica (PS) < 120 mmHg e pressão diastólica (PD) < 80 mmHg foram selecionados do banco de dados EVOPIU (Estudo da Velocidade de Onda de Pulso em Idosos em área Urbana no Brasil). Foram avaliadas a velocidade da onda de pulso carotídeo-femoral (VOPcf) e as pressões central e periférica em todos os pacientes. Os pacientes foram divididos em quatro grupos: G1: (n = 19; com VOPcf < 7,6 m/s; sem medicação), G2 (n = 26; VOPcf ≥ 7,6 m/s; sem medicação), G3 (n = 25; VOPcf < 7,6 m/s com medicação anti-hipertensiva), e G4 (n = 32; VOPcf ≥ 7,6 m/s com medicação anti-hipertensiva). Resultados: Em nossa amostra, 56,7% dos pacientes apresentaram VOPcf ≥ 7,6 m/s. A pressão sistólica central no G1 [99 (10) mmHg] foi inferior à encontrada nos outros três grupos [vs. 112 (14) mmHg, 111 (15), 112 (20) mmHg; P < 0,05)]. Conclusão: Pessoas idosas com pressão arterial ideal não necessariamente têm EVS e podem apresentar valores de VOPcf próximos aos limites estabelecidos para o diagnóstico de RAC.

Extracellular Non-Coding RNAs in Cardiovascular Diseases

Cardiovascular diseases (CVDs) remain the world's leading cause of death despite the best available healthcare and therapy. Emerging as a key mediator of intercellular and inter-organ communication in CVD pathogenesis, extracellular vesicles (EVs) are a heterogeneous group of membrane-enclosed nano-sized vesicles released by virtually all cells, of which their RNA cargo, especially non-coding RNAs (ncRNA), has been increasingly recognized as a promising diagnostic and therapeutic target. Recent evidence shows that ncRNAs, such as small ncRNAs, circular RNAs, and long ncRNAs, can be selectively sorted into EVs or other non-vesicular carriers and modulate various biological processes in recipient cells. In this review, we summarize recent advances in the literature regarding the origin, extracellular carrier, and functional mechanisms of extracellular ncRNAs with a focus on small ncRNAs, circular RNAs, and long ncRNAs. The pathophysiological roles of extracellular ncRNAs in various CVDs, including atherosclerosis, ischemic heart diseases, hypertension, cardiac hypertrophy, and heart failure, are extensively discussed. We also provide an update on recent developments and challenges in using extracellular ncRNAs as biomarkers or therapeutical targets in these CVDs.

Nuclear Factor of Activated T Cells-5 Regulates Notochord Lumenogenesis in Chordate Larval Development

Osmoregulation is essential for organisms to adapt to the exterior environment and plays an important role in embryonic organogenesis. Tubular organ formation usually involves a hyperosmotic lumen environment. The mechanisms of how the cells respond and regulate lumen formation remain largely unknown. Here, we reported that the nuclear factor of activated T cells-5 (NFAT5), the only transcription factor in the NFAT family involved in the cellular responses to hypertonic stress, regulated notochord lumen formation in chordate Ciona. Ciona NFAT5 (Ci-NFAT5) was expressed in notochord, and its expression level increased during notochord lumen formation and expansion. Knockout and expression of the dominant negative of NFAT5 in Ciona embryos resulted in the failure of notochord lumen expansion. We further demonstrated that the Ci-NFAT5 transferred from the cytoplasm into nuclei in HeLa cells under the hyperosmotic medium, indicating Ci-NFAT5 can respond the hypertonicity. To reveal the underly mechanisms, we predicted potential downstream genes of Ci-NFAT5 and further validated Ci-NFAT5-interacted genes by the luciferase assay. The results showed that Ci-NFAT5 promoted SLC26A6 expression. Furthermore, expression of a transport inactivity mutant of SLC26A6 (L421P) in notochord led to the failure of lumen expansion, phenocopying that of Ci-NFAT5 knockout. These results suggest that Ci-NFAT5 regulates notochord lumen expansion via the SLC26A6 axis. Taken together, our results reveal that the chordate NFAT5 responds to hypertonic stress and regulates lumen osmotic pressure via an ion channel pathway on luminal organ formation.

Dose-Response Effect of Coenzyme Q10 Supplementation on Blood Pressure among Patients with Cardiometabolic Disorders: A Grading of Recommendations Assessment, Development, and Evaluation (GRADE)-Assessed Systematic Review and Meta-Analysis of Randomized Controlled Trials

Previous studies have shown beneficial effects of coenzyme Q10 (CoQ10) supplementation on blood pressure (BP). However, the optimal intake of CoQ10 for BP regulation in patients with cardiometabolic disorders is unknown, and its effect on circulating CoQ10 is also unclear. We aimed to assess the dose-response relation between CoQ10 and BP, and quantify the effect of CoQ10 supplementation on the concentration of circulating CoQ10 by synthesizing available evidence from randomized controlled trials (RCTs). A comprehensive literature search was performed in 3 databases (PubMed/MEDLINE, Embase, and Cochrane Library) to 21 March, 2022. A novel 1-stage restricted cubic spline regression model was used to evaluate the nonlinear dose-response relation between CoQ10 and BP. Twenty-six studies comprising 1831 subjects were included in our meta-analysis. CoQ10 supplementation significantly reduced systolic blood pressure (SBP) (-4.77 mmHg, 95% CI: -6.57, -2.97) in patients with cardiometabolic diseases; this reduction was accompanied by a 1.62 (95% CI: 1.26, 1.97) μg/mL elevation of circulating CoQ10 compared with the control group. Subgroup analyses revealed that the effects of reducing SBP were more pronounced in patients with diabetes and dyslipidemia and in studies with longer durations (>12 wk). Importantly, a U-shaped dose-response relation was observed between CoQ10 supplementation and SBP level, with an approximate dose of 100-200 mg/d largely reducing SBP (χ2 = 10.84, Pnonlinearity = 0.004). The quality of evidence was rated as moderate, low, and very low for SBP, diastolic blood pressure (DBP), and circulating CoQ10 according to the Grading of Recommendations, Assessment, Development, and Evaluation approach (GRADE), respectively. The current finding demonstrated that the clinically beneficial effects of CoQ10 supplementation may be attributed to the reduction in SBP, and 100-200 mg/d of CoQ10 supplementation may achieve the greatest benefit on SBP in patients with cardiometabolic diseases. This study was registered on PROSPERO as CRD42021252933.

Behavioural, odontological and physical activity patterns of hypertense and control population

Behavioural and multifactorial factors such as odontological and physical activity habits are controlling factors in hypertension. The aim of the present study was to analyze differences in behavioral, odontological and physical activity patterns of hypertense and control population. Fifty participants with hypertension (57.5±13.6 years) and 100 participants as control group with no hypertension disease (48.9±7.9 years) were interviewed via online questionnaire. Multifactorial items in oral behavioral, health habits and physical activity profile were analyzed by a compendium of questionnaires. Result showed how control group showed significantly lower age, weight, body mass index, TV hours per day, gastritis or heartburn, dental sensibility, and sick days last year, and significantly higher level of academic education, quality of sleep and daily toothbrushing than hypertension group. In conclusion our results showed that hypertense patients presented higher levels of overweight, poor sleep quality and sedentary behaviors than control participants. In addition, hypertense patients also presented poor odontological health, showing higher indices of gastritis, dental sensibility, and sick days per year. Both groups presented a low physical activity pattern. This information allows to better understand of a multifactorial disease, as well to the creation of protocols for intervention and prevention of this disease at the behavioral level and lifestyle.

Vasoprotective Endothelial Effects of Chronic Cannabidiol Treatment and Its Influence on the Endocannabinoid System in Rats with Primary and Secondary Hypertension

Our study aimed to examine the endothelium (vascular)-protecting effects of chronic cannabidiol (CBD) administration (10 mg/kg once daily for 2 weeks) in aortas and small mesenteric (G3) arteries isolated from deoxycorticosterone-induced hypertensive (DOCA-salt) rats and spontaneously hypertensive rats (SHR). CBD reduced hypertrophy and improved the endothelium-dependent vasodilation in response to acetylcholine in the aortas and G3 of DOCA-salt rats and SHR. The enhancement of vasorelaxation was prevented by the inhibition of nitric oxide (NO) with L-NAME and/or the inhibition of cyclooxygenase (COX) with indomethacin in the aortas and G3 of DOCA-salt and SHR, respectively. The mechanism of the CBD-mediated improvement of endothelial function in hypertensive vessels depends on the vessel diameter and may be associated with its NO-, the intermediate-conductance calcium-activated potassium channel- or NO-, COX-, the intermediate and the small-conductance calcium-activated potassium channels-dependent effect in aortas and G3, respectively. CBD increased the vascular expression of the cannabinoid CB₁ and CB₂ receptors and aortic levels of endocannabinoids with vasorelaxant properties e.g., anandamide, 2-arachidonoylglycerol and palmitoyl ethanolamide in aortas of DOCA-salt and/or SHR. In conclusion, CBD treatment has vasoprotective effects in hypertensive rats, in a vessel-size- and hypertension-model-independent manner, at least partly via inducing local vascular changes in the endocannabinoid system.

Predictive Factors for Target Organ Injuries in Hypertensive Individuals

Background

The causal relationship between systemic arterial hypertension and target organ damage (TOD) is well known, as well as the association with cardiovascular risk factors (CV). Ambulatory blood pressure monitoring (ABPM) is important in monitoring hypertension and assessing the risk of TOD.

Objective

To evaluate the relationship between blood pressure (BP) and clinical and biochemical parameters in the development of TOD in hypertensive patients.

Methods

This was a retrospective cohort study with 162 hypertensive patients followed for an average period of 13 years. The TOD investigated were left ventricular hypertrophy (LVH), microalbuminuria, coronary artery disease (CAD) and stroke. Blood pressure was assessed by ABPM and LVH using echocardiogram and electrocardiogram, respectively. Biochemical-metabolic tests and 24-hour microalbuminuria were performed at baseline and follow-up. The P-value <0.05 was considered significant.

Results

The average age was 69±11.8 years, with a predominance of women (64.8%), white ethnicity (79.6%) and diabetics (78.4%). ABPM showed a significant reduction in BP values during follow-up, although without association with TOD (microalbuminuria, stroke, and CAD), except for LVH that showed a correlation with sleep BP ≥120/70 mmHg (P=0.044). The most frequent TODs were LVH (29.6%), microalbuminuria (26.5%), CAD (19.8%) and stroke (17.3%). In the follow-up, there was an association between LVH and diabetes; microalbuminuria was associated with diabetes and triglycerides; stroke was associated with HDL-cholesterol (HDL-c), microalbuminuria and carotid disease. CAD showed a relationship with age and HDL-c.

Conclusion

Predictive factors for TOD are age, microalbuminuria, diabetes, HDL-c, triglycerides and carotid disease. Nocturnal BP is correlated with LVH. The absence of a relationship between ABPM and other TODs can be explained by the use of effective drugs, improvement of metabolic and blood pressure parameters.

Novel Combined Antioxidant Strategy against Hypertension, Acute Myocardial Infarction and Postoperative Atrial Fibrillation

Reactive oxygen species (ROS) play a physiological role in the modulation of several functions of the vascular wall; however, increased ROS have detrimental effects. Hence, oxidative stress has pathophysiological impacts on the control of the vascular tone and cardiac functions. Recent experimental studies reported the involvement of increased ROS in the mechanism of hypertension, as this disorder associates with increased production of pro-oxidants and decreased bioavailability of antioxidants. In addition, increased ROS exposure is found in ischemia-reperfusion, occurring in acute myocardial infarction and cardiac surgery with extracorporeal circulation, among other settings. Although these effects cause major heart damage, at present, there is no available treatment. Therefore, it should be expected that antioxidants counteract the oxidative processes, thereby being suitable against cardiovascular disease. Nevertheless, although numerous experimental studies agree with this notion, interventional trials have provided mixed results. A better knowledge of ROS modulation and their specific interaction with the molecular targets should contribute to the development of novel multitarget antioxidant effective therapeutic strategies. The complex multifactorial nature of hypertension, acute myocardial infarction, and postoperative atrial fibrillation needs a multitarget antioxidant strategy, which may give rise to additive or synergic protective effects to achieve optimal cardioprotection.

Efficacy of synbiotic interventions on blood pressure: a systematic review and meta-analysis of clinical trials

PURPOSE

The present systematic review and meta-analysis aimed to evaluate the effect of synbiotic interventions on blood pressure levels in adults.

METHODS

A systematic literature search was conducted in the databases of MEDLINE, Scopus, Web of Science, and Cochrane through March 2020 to identify all randomized control trials (RCTs) investigating the effects of synbiotic interventions on blood pressure parameter, including systolic (SBP) and diastolic blood pressure (DBP). Grading of Recommendations Assessment, Development and Evaluation (GRADE) scale was used to assess the certainty of evaluated outcomes and determine the strength of recommendations.

RESULTS

Eleven RCTs were included in the meta-analysis. Synbiotic interventions significantly reduced SBP (-3.02 mmHg; 95% CI: -4.84, -1.21; I² = 55%) without changing DBP levels (-0.57 mmHg; 95% CI: -1.78, 0.64; I² = 50%). Subgroup analyses revealed that the SBP-lowering effects of synbiotic interventions were more pronounced wherein trials were longer (≥12 weeks), synbiotic interventions were administrated as a supplement, and participants were younger (<50 years old). Also, a significant improvement in both SBP and DBP levels was evident in subgroups with a lower (<30 kg/m²) body mass index.

CONCLUSIONS

Synbiotic interventions may significantly improve SBP levels in adults.

Vasomotor action of androgens in the mesenteric artery of hypertensive rats. Role of perivascular innervation

Androgens may exert cardiovascular protective actions by regulating the release and function of different vascular factors. In addition, testosterone (TES) and its 5-reduced metabolites, 5α- and 5β-dihydrotestosterone (5α- and 5β-DHT) induce vasorelaxant and hypotensive effects. Furthermore, hypertension has been reported to alter the release and function of the neurotransmitters nitric oxide (NO), calcitonin gene-related peptide (CGRP) and noradrenaline (NA). Since the mesenteric arteries possess a dense perivascular innervation and significantly regulate total peripheral vascular resistance, the objective of this study was to analyze the effect of TES, 5α- and 5β-DHT on the neurogenic release and vasomotor function of NO, CGRP and NA. For this purpose, the superior mesenteric artery from male spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats was used to analyze: (i) the effect of androgens (10 nM, incubated for 30 min) on the neurogenic release of NO, CGRP and NA and (ii) the vasoconstrictor-response to NA and the vasodilator responses to the NO donor, sodium nitroprusside (SNP) and exogenous CGRP. The results showed that TES, 5α- or 5β-DHT did not modify the release of NO, CGRP or NA induced by electrical field stimulation (EFS) in the arteries of SHR; however, in the arteries of WKY rats androgens only caused an increase in EFS-induced NO release. Moreover, TES, and especially 5β-DHT, increased the vasodilator response induced by SNP and CGRP in the arteries of SHR. These findings could be contributing to the hypotensive/antihypertensive efficacy of 5β-DHT previously described in conscious SHR and WKY rats, pointing to 5β- DHT as a potential drug for the treatment of hypertension.

Toward Individualized Approaches to Partial Nephrectomy: Assessing the Correlation Between Ischemia Time and Patient Health Status (RECORD2 Project)

BACKGROUND

Ischemia time during partial nephrectomy (PN) is among the greatest determinants of acute kidney injury (AKI). Whether this association is affected by the preoperative risk of AKI has never been investigated.

OBJECTIVE

To assess the effect of the interaction between the preoperative risk of AKI and ischemia time on the probability of AKI during PN.

DESIGN, SETTING, AND PARTICIPANTS

Data of 944 patients treated with on-clamp PN for cT1 renal tumors were extracted from the Registry of Conservative and Radical Surgery for Cortical Renal Tumor Disease (RECORD2) database, a prospective multicenter project.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We estimated the preoperative risk of AKI (defined according to the risk/injury/failure/loss/end-stage [RIFLE] criteria) according to age, baseline renal function, clinical stage, preoperative aspects and dimensions used for an anatomical (PADUA) score, and surgical approach. Classification and regression tree (CART) analysis identified patients at "high" and "low" risk of AKI. Finally, we plotted the probability of AKI over ischemia time stratified by the preoperative risk of AKI.

RESULTS AND LIMITATIONS

Overall, 235 (25%) patients experienced AKI after surgery. At multivariable analysis, older patients, those with more complex tumors, those with higher baseline function, and those treated with open surgery had an increased risk of AKI (all p ≤ 0.011). According to the first split at CART analysis, patients were categorized as those with "high" and "low" risk of AKI having a probability of >40% or <40%. For low-risk patients, the probability of AKI in case of <10 versus >20 min of ischemia was 13% versus 28% (absolute risk increase 15%). The risk of AKI for high-risk patients who had <10 versus >20 min of ischemia was 31% versus 77%. This corresponds to an absolute risk increase of 45%. Limitations include retrospective data analyses and lack of surgeons' prior experience.

CONCLUSIONS

Ischemia time during PN has different implications for patients with different health status. Clamp time seems less clinically relevant for patients in good conditions who may endure prolonged ischemia with a mild increase in the risk of AKI, whereas frail patients seem to be more vulnerable to ischemic damage even for short clamp time. For individualized intra- and postoperative management, duration of ischemia needs to be questioned in the context of the individual health status.

PATIENT SUMMARY

Functional sequelae related to ischemia time during partial nephrectomy depend on baseline health status. The correlation between the duration of ischemia and baseline health status should be taken into account toward individualized intra- and postoperative management.

Effects of Angiotensin-Converting Enzyme Inhibitors on Arterial Stiffness: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

To determine the effects of ACEIs on arterial stiffness, a meta-analysis of randomized controlled trials was conducted. Relevant articles that investigated the effects of ACEIs on arterial stiffness from PubMed, Embase, and the Cochrane library from inception to September 2018 were systematically retrieved. The investigated outcomes included brachial-ankle pulse wave velocity (ba-PWV) and carotid-femoral PWV (cf-PWV) by using weighted mean differences (WMDs) and 95% confidence intervals (CIs) with the random-effects model. A total of 17 RCTs including 1,458 individuals were included. The summary results indicated no significant differences between ACEIs and control for ba-PWV and cf-PWV. Also, no significant differences between ACEI and control for ba-PWV and cf-PWV were observed in hypertensive patients, while the therapeutic effects of ACEI versus placebo showed statistically significant difference. Moreover, subgroup analysis indicated that the levels of ba-PWV were significantly associated if the study was conducted in Western countries, mean age <60.0 years, percentage male ≥60.0%, compared with ARBs, baseline PWV <10.0, and high-quality study. Furthermore, the significant levels of cf-PWV in patients who received ACEIs were observed when percentage male was ≥60.0% and the studies were of high-quality. Finally, no significant differences were observed between ACEIs and other antihypertensive drugs regarding the changes of systolic blood pressure (SBP) and diastolic blood pressure (DBP). The overall analysis suggested no significant differences between ACEIs and other antihypertensive drugs for ba-PWV and cf-PWV levels, whereas ACEIs versus placebo showed lower levels of ba-PWV and cf-PWV.

Antihypertensive and renal protective effect of Shunaoxin pill combined with captopril on spontaneous hypertension rats

INTRODUCTION

According to previous reports, hypertension has become the most common chronic disease in the world. Captopril, an angiotensin-converting enzyme inhibitor, has been widely used for the therapy of arterial hypertension and cardiovascular diseases therapy. Besides, Shunaoxin pill (SNX) as a traditional Chinese prescription showed antihypertensive effect in our previous research.

OBJECTIVE

This study means to investigate whether SNX combining with captopril could show antihypertensive and renal protective effects on spontaneous hypertension rats (SHRs).

METHODS

SHRs were randomly assigned to four treatment groups, including non-treated group, captopril, SNX, and captopril + SNX-treated groups. Their body weight and systolic blood pressure (SBP) were measured weekly. Histopathological examination was analyzed through Masson staining and hematoxylin and eosin staining. Biochemical analyses, ELISA, and western blot were used to analyze their combining mechanism.

RESULTS

In this experiment, this combinatorial therapy significantly reduced aortic wall thickness, increased the content of NO, NOS and eNOS, decreased the content of bradykinin and endothelin 1(ET-1), and regulated the levels of TG, TC and HDLC back to normal, which suggested they could induce vasodilation and lower blood pressure. Meanwhile, histological examination alleviated that captopril + SNX remarkably inhibited renal injury, including tubular disorder, inflammatory cell infiltration and fibrosis. They down-regulated the serum levels of BUN and Cr, protein expression of IL-1β, NF-κB, Bax, Cyt c, caspase 3, 8 and 9 in kidney tissues and significantly increased the levels of Bcl-2 in kidney tissues compared with monotherapy group.

CONCLUSION

The combinatorial treatment of SNX and captopril lowered blood pressure through adjusting NO/NOS, ET-1 and dyslipidemia profile. Furthermore, this treatment alleviated the kidney damage via reducing the release of inflammatory factors and the expression of apoptotic markers. Therefore, these results provided a rationale for future clinical use of SNX combined with captopril in antihypertensive and protecting renal functions in hypertension.

Low-Dose Aspirin Treatment Attenuates Male Rat Salt-Sensitive Hypertension via Platelet Cyclooxygenase 1 and Complement Cascade Pathway

Background The role of platelets in the development of vascular inflammation and endothelial dysfunction in the pathogenesis of hypertension is well established at this time. Aspirin is known to relieve pain, decrease fever, reduce inflammation, impair platelet aggregation, and prevent clotting, yet its effect in the context of salt-sensitive hypertension remains unclear. The present study investigated the importance of aspirin in inhibiting the abnormal activation of platelets and promoting the normal function of the vascular endothelium in a rat model of salt-sensitive hypertension. Method and Results Dahl salt-sensitive rats and salt-resistant rats were fed a normal-salt diet (4% NaCl), a high-salt diet (8% NaCl), or a high-salt diet with aspirin gavage (10 mg/kg per day) for 8 weeks. Blood pressure, platelet activation, vascular function, inflammatory response, and potential mechanism were measured. Low-dose aspirin (10 mg/kg per day) decreased the high-salt diet-induced elevation of blood pressure, platelet activation, leukocyte infiltration, and leukocyte-platelet aggregation (CD45+CD61+), as well as vascular endothelial and renal damage. These effects were related to the ability of aspirin to prevent the adhesion of leukocytes to endothelial cells via inhibition of the platelet cyclooxygenase 1 but not the cyclooxygenase 2 pathway. Aspirin also reversed the high-salt diet-induced abnormal activation of complement and coagulation cascades in platelets. Conclusions These results highlight a new property of aspirin in ameliorating vascular endothelial dysfunction induced by platelet activation, which may be beneficial in the treatment of salt-sensitive hypertension.

Association Between Hypertension, Platelet Reactivity, and the Risk of Adverse Events After Percutaneous Coronary Intervention (From the ADAPT-DES Study)

Hypertension is associated with vascular and endothelial dysfunction that may result in a greater propensity for reactive platelets to cause thrombosis. We sought to assess whether the risk of major adverse cardiac events (MACE) after percutaneous coronary intervention (PCI) in patients with on-clopidogrel residual high platelet reactivity (HPR) varies in patients with versus without hypertension. Assessment of dual antiplatelet therapy with drug eluting stents (ADAPT-DES) was a prospective, multicenter registry of patients successfully treated with coronary drug-eluting stents (DES). HPR was defined as P2Y12 reaction units (PRU) >208, as assessed by the VerifyNow point-of-care assay. Multivariable Cox proportional hazards regression was used to assess whether the adjusted association between HPR and 2-year risk of MACE (cardiac death, myocardial infarction [MI], or stent thrombosis) was different in patients with versus without hypertension. A total of 6833 of 8582 patients (79.6%) had a history of hypertension. Patients with compared with those without hypertension were older, more likely to have other cardiovascular risk factors, and had higher PRU (190.1 ± 97.3 vs 179.5 ± 94.3; p <0.0001). Patients with hypertension had significantly higher 2-year rates of MACE (7.0% vs 4.4%, p <0.001), all-cause death (4.2% vs 2.5%, p = 0.001), and MI (5.2% vs 3.2%, p <0.001), and had nominally higher rates of stent thrombosis (1.0% vs 0.5%, p = 0.059). A significant interaction was present between hypertension and HPR regarding 2-year MACE risk (adjusted hazard ratio for HPR vs no HPR 1.38, 95% confidence interval 1.14 to 1.68 for patients with hypertension vs 0.81, 95% confidence interval 0.50 to 1.33 for patients without hypertension, p = 0.046). In conclusion, following successful PCI with DES, 2-year MACE rates are increased in patients with both hypertension and residual HPR on clopidogrel. HPR had a greater effect on the risk of adverse events among patients with versus without hypertension.

Hypertension-induced cardiac impairment is reversed by the inhibition of endoplasmic reticulum stress

OBJECTIVES

Endoplasmic reticulum stress (ERS) has been shown to play a crucial role in the pathogenesis of hypertension. However, the role and mechanisms of ERS on hypertension-induced cardiac functional and morphological changes remain unclear. In this study, the effect of ERS inhibition with tauroursodeoxycholic acid (TUDCA) on hypertension-induced cardiac remodelling was examined.

METHODS

Hypertension was induced by deoxycorticosterone-acetate (DOCA) and salt administration in uni-nephrectomized rats for 12 weeks. TUDCA was administered for the last four weeks. Rhythmic activity and contractions of the right atrium and left papillary muscle (LPM) were recorded. In the left ventricle, the expression of various proteins was examined and histopathological evaluation was performed.

KEY FINDINGS

Hypertension-induced increments in systolic blood pressure and ventricular contractions were reversed by TUDCA. In the hypertensive heart, while expressions of glucose-regulated protein-78 (GRP78), phospho-dsRNA-activated protein kinase-like ER kinase (p-PERK), sarcoplasmic reticulum Ca-ATPase-2 (SERCA2), matrix metalloproteinase-2 (MMP-2) and nuclear NF-κB p65 increased; Bcl-2 (B-cell lymphoma-2) expression decreased and the altered levels of all these markers were restored by TUDCA. In the microscopic examination, TUDCA treatment attenuated hypertension-stimulated cardiac inflammation and fibrosis.

CONCLUSIONS

These results suggest that ERS inhibition may ameliorate cardiac contractility through improving ERS-associated calcium mishandling, apoptosis, inflammation and fibrosis, thereby offering therapeutic potential in hypertension-induced cardiac dysfunction.

Effect of Different Classes of Antihypertensive Drugs on Endothelial Function and Inflammation

Hypertension is characterized by structural and functional changes in blood vessels that travel with increased arterial stiffness, vascular inflammation, and endothelial dysfunction. Some antihypertensive drugs have been shown to improve endothelial function and reduce levels of inflammatory markers regardless of the effect of blood pressure lowering. Third-generation β-blockers, such as nebivolol and carvedilol, because they have additional properties, have been shown to improve endothelial function in patients with hypertension. Calcium channel antagonists, because they have antioxidant effects, may improve endothelial function and vascular inflammation.The Angiotensin Receptor Blocker (ARBs) are able to improve endothelial dysfunction and vascular inflammation in patients with hypertension and other cardiovascular diseases. Angiotensin converting enzyme (ACE) inhibitors have shown beneficial effects on endothelial function in patients with hypertension and other cardiovascular diseases, however there are few studies evaluating the effect of treatment with this class on the reduction of C-reactive protein (CRP) levels. Further studies are needed to assess whether treatment of endothelial dysfunction and vascular inflammation may improve the prognosis of patients with essential hypertension.

Collagen-Based Tissue Engineering Strategies for Vascular Medicine

Cardiovascular diseases (CVDs) account for the 31% of total death per year, making them the first cause of death in the world. Atherosclerosis is at the root of the most life-threatening CVDs. Vascular bypass/replacement surgery is the primary therapy for patients with atherosclerosis. The use of polymeric grafts for this application is still burdened by high-rate failure, mostly caused by thrombosis and neointima hyperplasia at the implantation site. As a solution for these problems, the fast re-establishment of a functional endothelial cell (EC) layer has been proposed, representing a strategy of crucial importance to reduce these adverse outcomes. Implant modifications using molecules and growth factors with the aim of speeding up the re-endothelialization process has been proposed over the last years. Collagen, by virtue of several favorable properties, has been widely studied for its application in vascular graft enrichment, mainly as a coating for vascular graft luminal surface and as a drug delivery system for the release of pro-endothelialization factors. Collagen coatings provide receptor-ligand binding sites for ECs on the graft surface and, at the same time, act as biological sealants, effectively reducing graft porosity. The development of collagen-based drug delivery systems, in which small-molecule and protein-based drugs are immobilized within a collagen scaffold in order to control their release for biomedical applications, has been widely explored. These systems help in protecting the biological activity of the loaded molecules while slowing their diffusion from collagen scaffolds, providing optimal effects on the targeted vascular cells. Moreover, collagen-based vascular tissue engineering substitutes, despite not showing yet optimal mechanical properties for their use in the therapy, have shown a high potential as physiologically relevant models for the study of cardiovascular therapeutic drugs and diseases. In this review, the current state of the art about the use of collagen-based strategies, mainly as a coating material for the functionalization of vascular graft luminal surface, as a drug delivery system for the release of pro-endothelialization factors, and as physiologically relevant in vitro vascular models, and the future trend in this field of research will be presented and discussed.

Endothelium-dependent adaptation of arterial wall viscosity during blood flow increase is impaired in essential hypertension

BACKGROUND AND AIMS

Arterial wall viscosity (AWV) is regulated by endothelium-derived NO and epoxyeicosatrienoic acids (EETs) under baseline physiological conditions. Whether these factors regulate AWV during blood flow increase and whether this mechanism is affected in essential hypertensive patients (HT) remain unknown.

METHODS

The evolution of radial artery diameter, wall thickness and arterial pressure in response to an increase in flow induced by hand skin heating were measured in 18 untreated HT and 14 normotensive controls (NT) during local infusion of saline and the respective pharmacological inhibitors of NO-synthase and EETs synthesis by cytochrome P450, L-NMMA and/or fluconazole. AWV was estimated by the ratio of the viscous energy dissipated (W_V) to the elastic energy stored (W_E) obtained from the pressure-diameter relationship. Concomitant changes in operating conditions, which influence the AWV, were taken into account by calculating the midwall stress.

RESULTS

Baseline W_V and W_E were higher in HT than in NT but W_V/W_E was similar. In saline condition, W_V/W_E increased in HT during heating but not in NT. In the presence of L-NMMA and/or fluconazole, W_V/W_E increased during heating in NT. In contrast, these inhibitors did not modify the increase in W_V/W_E during heating in HT compared to saline. In all conditions, a larger increase in W_V than W_E was responsible for the increase in W_V/W_E.

CONCLUSIONS

The release of NO and EETs maintains a stable AWV during flow increase and this endothelial adaptive regulation is lost during essential hypertension, which may promote excessive viscous energy dissipation and cardiovascular uncoupling. Restoration of EETs availability with inhibitors of soluble epoxide hydrolase could thus constitute a promising pharmacological approach to restore the endothelial adaptive regulation of AWV.

The effects of LXR agonist GW3965 on vascular reactivity and inflammation in hypertensive rat aorta

AIMS

Liver X receptors (LXRs) play an important role in the regulation of cholesterol, fatty acid and glucose metabolisms together with inflammatory processes. In the present study, the effects of LXR agonist GW3965 on vascular reactivity and expression of functional proteins in DOCA-Salt induced hypertension were examined.

MAIN METHODS

Hypertension was induced through unilateral nephrectomy and deoxycorticosterone-acetate (DOCA) injection (20 mg/kg, twice a week) for 6 weeks in male Wistar albino rats (8 weeks old). An LXR agonist GW3965 (10 mg/kg/day, i.p.) was administered to animals for last seven days.

KEY FINDINGS

GW3965 treatment reduced systolic blood pressures in hypertensive rats. Acetylcholine-induced endothelium-dependent and sodium nitroprusside-induced endothelium-independent vasorelaxations were decreased in hypertensive rats but not affected by GW3965. GW3965 treatment enhanced plasma nitrite levels in normotensive rats. KCl and phenylephrine (Phe)-induced vasocontractions were reduced in hypertensive groups and increased with GW3965 treatment. Decreased sarco/endoplasmic reticulum Ca²⁺-ATPase2 (SERCA2) expression in the hypertensive aorta was not changed by GW3965 treatment. Expression of inositoltrisphosphate receptor1 (IP3R1) was increased by GW3965 in normotensive animals. The nuclear factor kappaB (NF-κB) and tumor necrosis factor alpha (TNF-α) expressions were increased in hypertensive rats and reduced by GW3965 treatment.

SIGNIFICANCE

The results of study indicate that the LXR agonist, GW3965, exhibited a beneficial effect on increased blood pressure and improved hypertension-induced impairment in contractile activity of vessel and inflammatory markers in vascular tissue. Therefore, these effects of LXR agonists on vessel should be taken into account in experimental or therapeutic approaches to hypertension.

Potential Role of Antihypertensive Medications in Preventing Excessive Arterial Stiffening

PURPOSE OF REVIEW

Increased arterial stiffness, an abnormal structural and functional change in the vascular wall, is a precursor for hypertension, coronary heart disease, stroke, and associated cardiovascular disease (CVD). The aim of this paper is to review the etiology of arterial stiffening and potential therapeutic approaches to modulate arterial fibrosis and stiffness.

RECENT FINDINGS

The Framingham Heart Study demonstrated that arterial stiffness is an independent predictor of CVD and related morbidity and mortality. Dysfunction of endothelial cells, vascular smooth muscle cells, extracellular matrix, and other functional elements of the vessel wall contribute to underlying pathophysiology of increased arterial stiffness. An activated renin-angiotensin-aldosterone system, oxidative stress, abnormal peri-vascular adipose tissue, inflammation, and increased sympathetic nervous system activity are associated with the development and progression of arterial fibrosis, stiffening, and associated CVD. In this review, we will discuss the structural and function changes and mechanisms of the vessel wall in arterial stiffness and provide potential therapeutic strategies.

Red alga polysaccharides attenuate angiotensin II-induced inflammation in coronary endothelial cells

The pro-inflammatory vasoconstrictor Angiotensin II can cause endothelial dysfunction and is considered to be one of the mediators of atherosclerosis. Our former results demonstrated that polysaccharides derived from the red alga Porphyridium sp. attenuate inflammatory processes by interfering with tumor necrosis factor-alpha-induced inflammation, in human coronary artery endothelial cells. However, the anti-inflammatory effect of these polysaccharides on inflammation processes occurring under Angiotensin II stimulation is yet unknown. Herein, we studied the polysaccharide's anti-inflammatory effect by quantification of inflammatory markers in Angiotensin II- stimulated Human Coronary Artery Endothelial Cells following pre-treatment with polysaccharides. Inflammatory atherosclerotic pathways up-regulated by Angiotensin II, including adhesion molecule expression and nuclear factor kappa-light-chain-enhancer of activated B cells translocation, were significantly attenuated or diminished in cells pre-treated with the polysaccharides. In addition, the polysaccharides increased the antioxidant response elements activity through the nuclear factor-E2-related factor 2- antioxidant protection system. These polysaccharide's promising abilities may be considered as a basis for future use as a therapeutic agent aimed at improving vascular health by attenuation of the inflammatory atherosclerotic process.

Diabetes, Hypertension, and Cardiovascular Disease: Clinical Insights and Vascular Mechanisms

Hypertension and type 2 diabetes are common comorbidities. Hypertension is twice as frequent in patients with diabetes compared with those who do not have diabetes. Moreover, patients with hypertension often exhibit insulin resistance and are at greater risk of diabetes developing than are normotensive individuals. The major cause of morbidity and mortality in diabetes is cardiovascular disease, which is exacerbated by hypertension. Accordingly, diabetes and hypertension are closely interlinked because of similar risk factors, such as endothelial dysfunction, vascular inflammation, arterial remodelling, atherosclerosis, dyslipidemia, and obesity. There is also substantial overlap in the cardiovascular complications of diabetes and hypertension related primarily to microvascular and macrovascular disease. Common mechanisms, such as upregulation of the renin-angiotensin-aldosterone system, oxidative stress, inflammation, and activation of the immune system likely contribute to the close relationship between diabetes and hypertension. In this article we discuss diabetes and hypertension as comorbidities and discuss the pathophysiological features of vascular complications associated with these conditions. We also highlight some vascular mechanisms that predispose to both conditions, focusing on advanced glycation end products, oxidative stress, inflammation, the immune system, and microRNAs. Finally, we provide some insights into current therapies targeting diabetes and cardiovascular complications and introduce some new agents that may have vasoprotective therapeutic potential in diabetes.

Dominant functional role of the novel phosphorylation site S811 in the human renal NaCl cotransporter

The NaCl cotransporter (NCC) is essential for electrolyte homeostasis and control of blood pressure. The human SLC12A3 gene, which encodes NCC, gives rise to 3 isoforms, of which only the shortest isoform [NaCl cotransporter isoform 3 (NCC₃)] has been studied extensively. All NCC isoforms share key phosphorylation sites at T55 and T60 that are essential mediators of NCC function. Recently, a novel phosphorylation site at S811 was identified in isoforms 1 and 2 [NaCl cotransporter splice variant (NCC_SV)], which are only present in humans and higher primates. The aim of the current study, therefore, is to investigate the role of S811 phosphorylation in the regulation of NCC by a combination of biochemical and fluorescent microscopy analyses. We demonstrate that hypotonic low-chloride buffer increases S811 phosphorylation, whereas phosphorylation-deficient S811A mutant hinders phosphorylation at T55 and T60 in NCC_SV and NCC₃. NCC_SV S811A impairs NCC₃ activity in a dominant-negative fashion, although it does not affect plasma membrane abundance. This effect may be explained by the heterodimerization of NCC_SV with NCC₃. Taken together, our study highlights the dominant-negative effect of NCC_SV on T55 and T60 phosphorylation and NCC activity. Here, we reveal a new function of NCC_SV in humans that broadens the understanding on NCC regulation in blood pressure control.-Tutakhel, O. A. Z., Bianchi, F., Smits, D. A., Bindels, R. J. M., Hoenderop, J. G. J., van der Wijst, J. Dominant functional role of the novel phosphorylation site S811 in the human renal NaCl cotransporter.

Polymer blends used to develop felodipine-loaded hollow microspheres for improved oral bioavailability

Felodipine (FD) has been widely used in anti-hypertensive treatment. However, it has extremely low aqueous solubility and poor bioavailability. To address these problems, FD hollow microspheres as multiple-unit dosage forms were synthesized by a solvent diffusion evaporation method. Particle size of the hollow microspheres, types of ethylcellulose (EC), amounts of EC, polyvinyl pyrrolidone (PVP) and FD were investigated based on an orthogonal experiment of three factors and three levels. In addition, the release kinetics in vitro and pharmacokinetics in beagle dogs of the optimized FD hollow microspheres was investigated and compared with Plendil (commercial FD sustained-release tablets) as a single-unit dosage form. Results showed that the optimal formulation was composed of EC_{10 cp}:PVP:FD (0.9:0.16:0.36, w/w). The FD hollow microspheres were globular with a hollow structure and have high drug loading (17.69±0.44%) and floating rate (93.82±4.05%) in simulated human gastric fluid after 24h. Pharmacokinetic data showed that FD hollow microspheres exhibited sustained-release behavior and significantly improved relative bioavailability of FD compared with the control. Pharmacodynamic study showed that the FD hollow microspheres could effectively lower blood pressure. Therefore, these findings demonstrated that the hollow microspheres were an effective sustained-release delivery system for FD.

Unsweetening the Heart: Possible Pleiotropic Effects of SGLT2 Inhibitors on Cardio and Cerebrovascular Alterations in Resistant Hypertensive Subjects

Resistant hypertension (RH) is a multifactorial disease associated with several target organ damage, such as microalbuminuria, left ventricular hypertrophy, and arterial stiffness. These subjects have high cardiovascular complications, especially when associated with diabetes condition. Sodium glucose cotransporter 2 (SGLT-2) inhibitors represent a new class of oral antidiabetic drugs that have shown positive effects in diabetics and even hypertensives subjects. Several studies demonstrated positive outcomes related to blood pressure levels, body weight, and glycemic control. Also found a reduction on microalbuminuria, cardiac and arterial remodeling process, and decrease in hospitalization care due heart failure. Despite these positive effects, the outcomes found for stroke were conflicted and tend neutral effect. Based on this, we sought to assess the pleiotropic effects of SGLT-2 inhibitors and the possible impact in RH subjects. In order to analyze the prospects of SGLT-2 inhibitors as a possible medication to complement the therapy manage of this high-risk class of patients.

Angiotensin II Receptor-Neprilysin Inhibitor Sacubitril/Valsartan Improves Endothelial Dysfunction in Spontaneously Hypertensive Rats

BACKGROUND

We have previously demonstrated that antihypertensive treatment with renin-angiotensin system inhibitors restores the impaired endothelium-dependent hyperpolarization (EDH)-mediated responses in spontaneously hypertensive rats (SHRs). Herein, we investigated whether the angiotensin II receptor-neprilysin inhibitor sacubitril/valsartan (LCZ696) would improve reduced EDH-mediated responses and whether LCZ696 would exert additional effects on endothelium-dependent and endothelium-independent vasorelaxation compared with an angiotensin II type 1 receptor blocker alone during hypertension.

METHODS AND RESULTS

SHRs were treated for 3 months with either LCZ696 or valsartan, from the age of 8 to 11 months. Age-matched, untreated SHRs and Wistar-Kyoto rats served as controls. Membrane potentials and contractile responses were recorded from the isolated superior mesenteric arteries. Acetylcholine-induced, EDH-mediated responses were impaired in untreated SHRs compared with Wistar-Kyoto rats. EDH-mediated responses were similarly improved in the LCZ696- and valsartan-treated SHRs. No difference was observed in acetylcholine-induced, nitric oxide-mediated relaxations among the 4 groups. Endothelium-independent relaxations in response to a nitric oxide donor, sodium nitroprusside, and those to levcromakalim, an ATP-sensitive K+-channel opener, were similar among the 4 groups; however, the sensitivities to levcromakalim were significantly higher in both LCZ696- and valsartan-treated SHRs.

CONCLUSIONS

LCZ696 appears to be as effective as valsartan in improving the impaired EDH-mediated responses during hypertension. LCZ696 and valsartan exert similar beneficial effects on endothelium-independent relaxation via enhanced sensitivity of the ATP-sensitive K+ channel. However, the dual blockade of renin-angiotensin system and neutral endopeptidase with LCZ696 does not appear to provide additional benefit over valsartan alone on vasomotor function in mesenteric arteries of SHRs.

Human Missense Mutations in Regulator of G Protein Signaling 2 Affect the Protein Function Through Multiple Mechanisms

Regulator of G protein signaling 2 (RGS2) plays a significant role in alleviating vascular contraction and promoting vascular relaxation due to its GTPase accelerating protein activity toward Gαq. Mice lacking RGS2 display a hypertensive phenotype, and several RGS2 missense mutations have been found predominantly in hypertensive human subjects. However, the mechanisms whereby these mutations could impact blood pressure is unknown. Here, we selected 16 rare, missense mutations in RGS2 identified in various human exome sequencing projects and evaluated their ability to inhibit intracellular calcium release mediated by angiotensin II receptor type 1 (AT1R). Four of them had reduced function and were further investigated to elucidate underlying mechanisms. Low protein expression, protein mislocalization, and reduced G protein binding were identified as likely mechanisms of the malfunctioning mutants. The Q2L mutant had 50% lower RGS2 than wild-type (WT) protein detected by Western blot. Confocal microscopy demonstrated that R44H and D40Y had impaired plasma membrane targeting; only 46% and 35% of those proteins translocated to the plasma membrane when coexpressed with Gα_q Q209L compared with 67% for WT RGS2. The R188H mutant had a significant reduction in Gα_q binding affinity (10-fold increase in K_i compared with WT RGS2 in a flow cytometry competition binding assay). This study provides functional data for 16 human RGS2 missense variants on their effects on AT1R-mediated calcium mobilization and provides molecular understanding of those variants with functional loss in vitro. These molecular behaviors can provide insight to inform antihypertensive therapeutics in individuals with variants having reduced function.

Arterial stiffness and cognitive impairment

BACKGROUND

Arterial stiffness is one of the earliest indicators of changes in vascular wall structure and function and may be assessed using various indicators, such as pulse-wave velocity (PWV), the cardio-ankle vascular index (CAVI), the ankle-brachial index (ABI), pulse pressure (PP), the augmentation index (AI), flow-mediated dilation (FMD), carotid intima media thickness (IMT) and arterial stiffness index-β. Arterial stiffness is generally considered an independent predictor of cardiovascular and cerebrovascular diseases. To date, a significant number of studies have focused on the relationship between arterial stiffness and cognitive impairment.

OBJECTIVES AND METHODS

To investigate the relationships between specific arterial stiffness parameters and cognitive impairment, elucidate the pathophysiological mechanisms underlying the relationship between arterial stiffness and cognitive impairment and determine how to interfere with arterial stiffness to prevent cognitive impairment, we searched PUBMED for studies regarding the relationship between arterial stiffness and cognitive impairment that were published from 2000 to 2017. We used the following key words in our search: "arterial stiffness and cognitive impairment" and "arterial stiffness and cognitive impairment mechanism". Studies involving human subjects older than 30years were included in the review, while irrelevant studies (i.e., studies involving subjects with comorbid kidney disease, diabetes and cardiac disease) were excluded from the review.

RESULTS

We determined that arterial stiffness severity was positively correlated with cognitive impairment. Of the markers used to assess arterial stiffness, a higher PWV, CAVI, AI, IMT and index-β and a lower ABI and FMD were related to cognitive impairment. However, the relationship between PP and cognitive impairment remained controversial. The potential mechanisms linking arterial stiffness and cognitive impairment may be associated with arterial pulsatility, as greater arterial pulsatility damages the cerebral microcirculation, which causes various phenomena associated with cerebral small vessel diseases (CSVDs), such as white matter hyperintensities (WMHs), cerebral microbleeds (CMBs), and lacunar infarctions (LIs). The mechanisms underlying the relationship between arterial stiffness and cognitive impairment may also be associated with reductions in white matter and gray matter integrity, medial temporal lobe atrophy and Aβ protein deposition. Engaging in more frequent physical exercise; increasing flavonoid and long-chain n-3 polyunsaturated fatty acid consumption; increasing tea, nitrite, dietary calcium and vitamin D intake; losing weight and taking medications intended to improve insulin sensitivity; quitting smoking; and using antihypertensive drugs and statins are early interventions and lifestyle changes that may be effective in preventing arterial stiffness and thus preventing cognitive impairment.

CONCLUSION

Arterial stiffness is a sensitive predictor of cognitive impairment, and arterial stiffness severity has the potential to serve as an indicator used to facilitate treatments designed to prevent or delay the onset and progression of dementia in elderly individuals. Early treatment of arterial stiffness is beneficial and recommended.

Impaired Muscle Oxygenation and Elevated Exercise Blood Pressure in Hypertensive Patients: Links With Vascular Stiffness

This study examined in vivo (1) skeletal muscle oxygenation and microvascular function, at rest and during handgrip exercise, and (2) their association with macrovascular function and exercise blood pressure (BP), in newly diagnosed, never-treated patients with hypertension and normotensive individuals. Ninety-one individuals (51 hypertensives and 40 normotensives) underwent office and 24-hour ambulatory BP, arterial stiffness, and central aortic BP assessment, followed by a 5-minute arterial occlusion and a 3-minute submaximal handgrip exercise. Changes in muscle oxygenated and deoxygenated hemoglobin and tissue oxygen saturation were continuously monitored by near-infrared spectroscopy and beat-by-beat BP by Finapres. Hypertensives had higher (P<0.001) central aortic BP and pulse wave velocity versus normotensives and exhibited (1) a blunted tissue oxygen saturation response during occlusion, with slower (P=0.006) deoxygenation rate, suggesting reduced muscle oxidative capacity, and (2) a slower reoxygenation rate and blunted hyperemic response (P<0.05), showing reduced microvascular reactivity. Muscle oxygenation responses were correlated with aortic systolic and pulse pressure and augmentation index (P<0.05; age and body mass index (BMI) adjusted). When exercising at the same submaximal intensity, hypertensives required a significantly greater (P<0.001) increase in BP for achieving similar muscle oxygenation levels as normotensives. This response was correlated with the magnitude of microvascular hyperemia and aortic BP. In conclusion, nontreated patients with hypertension exhibit prominent reductions in in vivo indices of skeletal muscle oxidative capacity, suggestive of mitochondrial dysfunction, and blunted muscle microvascular reactivity. These dysfunctions were associated with higher aortic systolic BP and arterial stiffness. Dysregulations in muscle oxygen delivery/utilization and microvascular stiffness, in hypertensive patients, partially contribute to their exaggerated BP during exercise.