The vascular endothelium: A regulator of arterial tone and interface for the immune system

Higher Food and Lifestyle Oxidative Balance Scores Decreases the Risk of Hypertension in Chinese Adults: A Population-Based Cross-Sectional Study

Oxidative stress plays an important role in the development of hypertension (HTN). A population-based cross-sectional study was conducted in Fujian province of China. The construction of FoodL-OBS relied on diet and lifestyle components, which included four food and six lifestyle factors. Multivariable-adjusted logistic regression was performed to investigate the association between FoodL-OBS and the risk of HTN. A subgroup analysis was also conducted. Restricted cubic spline (RCS) regression was used to elucidate the dose-response relationship between FoodL-OBS and the risk of HTN. A total of 9578 participants were included, 3271 of whom suffered from HTN. The results of multivariable logistic regression analysis showed that the HTN risk decreased by 14% for each FoodL-OBS unit added [OR: 0.86 (0.84, 0.88), p < 0.01]. Compared with participants with the lowest levels of Food-L-OBS, those with the highest quartile were less likely to have HTN [0.43 (0.37, 0.50)]. Further stratified analysis showed that Food-L-OBS was negatively associated with the risk of HTN, which was statistically significant in participants in subgroups of ≤60 years, female, and no-dyslipidemia. The results of RCS showed a linear negative correlation between Food-L-OBS and HTN in men, but not in women. In conclusion, FoodL-OBS was negatively associated with HTN, and a healthy lifestyle and antioxidant-rich diet may be useful for preventing HTN.

Knowledge domains and hotspots of the association between hypertension and noise: a bibliometric analysis and visualization study from 2003 to 2023

Objectives

Noise pollution has become an increasingly severe environmental issue in modern society and has been recognized for its adverse effects on cardiovascular diseases. Hypertension induced by noise exposure has garnered significant research interest and a large quantity of studies have been conducted. This study aims to employ bibliometric methods to comprehensively review the literature on the relationship between noise exposure and hypertension and to analyze the current state of research by identifying key areas of focus while also exploring future trends in this field.

Methods

The bibliometric analysis was conducted using the Web of Science Core Collection (WoSCC) database. The search query included terms related to noise pollution and hypertension. The timeframe for the search was from 2003 to 2023. Data analysis and visualization were performed using VOSviewer, CiteSpace, Scimago Graphica, and Rtools, focusing on publication trends, citation metrics, explosive intensity, and collaborative networks. Pajek was used to adjust pictures.

Results

The bibliometric analysis showed a notable rise in research output on the relationship between noise pollution and hypertension. The United States led in the number of publications, with China and Germany coming next. The study identified several key contributors, with Muenzel Thomas being the most prolific author, followed by Daiber Andreas and Pershagen Goran. Institutionally, Johannes Gutenberg University Mainz emerged as the leading institution in terms of publications, followed by Karolinska Institute. Collaborative networks among institutions highlighted significant international cooperation, with extensive collaborations observed, particularly between European and North American institutions. The study also pinpointed research hotspots and emerging trends through keyword analysis. Key areas of focus included the mechanisms linking noise exposure to hypertension, the impact of noise on cardiovascular health, and the role of environmental stressors.

Conclusions

This study advances our understanding of noise-induced hypertension's physiological and biological mechanisms, emphasizing the need for continued research. The research underscores the necessity of addressing noise pollution as a significant public health concern.

Relevance of Lipoprotein Composition in Endothelial Dysfunction and the Development of Hypertension

Endothelial dysfunction and chronic inflammation are determining factors in the development and progression of chronic degenerative diseases, such as hypertension and atherosclerosis. Among the shared pathophysiological characteristics of these two diseases is a metabolic disorder of lipids and lipoproteins. Therefore, the contents and quality of the lipids and proteins of lipoproteins become the targets of therapeutic objective. One of the stages of lipoprotein formation occurs through the incorporation of dietary lipids by enterocytes into the chylomicrons. Consequently, the composition, structure, and especially the properties of lipoproteins could be modified through the intake of bioactive compounds. The objective of this review is to describe the roles of the different lipid and protein components of lipoproteins and their receptors in endothelial dysfunction and the development of hypertension. In addition, we review the use of some non-pharmacological treatments that could improve endothelial function and/or prevent endothelial damage. The reviewed information contributes to the understanding of lipoproteins as vehicles of regulatory factors involved in the modulation of inflammatory and hemostatic processes, the attenuation of oxidative stress, and the neutralization of toxins, rather than only cholesterol and phospholipid transporters. For this review, a bibliographic search was carried out in different online metabases.

The Relevance of the Endothelium in Cardiopulmonary Disorders

The endothelium is a cell monolayer that lines vessels and separates tissues from blood flow. Endothelial cells (ECs) have a multitude of functions, including regulating blood flow and systemic perfusion through changes in vessel diameter. When an injury occurs, the endothelium is affected by altering its functions and structure, which leads to endothelial dysfunction, a characteristic of many vascular diseases. Understanding the role that the endothelium plays in pulmonary vascular and cardiopulmonary diseases, and exploring new therapeutic strategies is of utmost importance to advance clinically. Currently, there are several treatments able to improve patients' quality of life, however, none are effective nor curative. This review examines the critical role of the endothelium in the pulmonary vasculature, investigating the alterations that occur in ECs and their consequences for blood vessels and potential molecular targets to regulate its alterations. Additionally, we delve into promising non-pharmacological therapeutic strategies, such as exercise and diet. The significance of the endothelium in cardiopulmonary disorders is increasingly being recognized, making ECs a relevant target for novel therapies aimed at preserving their functional and structural integrity.

Vasorelaxant and Hypotensive Effects of Galla chinensis in Rats

Previous studies have revealed the medicinal and therapeutic effects of Galla chinensis. However, no studies have focused on the antihypertensive effects of G. chinensis. Therefore, we aimed to determine the vasorelaxant and hypotensive effects of G. chinensis 50% ethanolic extract (GCE). To evaluate the vascular relaxing effect of GCE, experiments were conducted using aortic segments dissected from Sprague Dawley rats. GCE showed a vasorelaxant effect via the nitric oxide/cyclic guanosine 3',5'-monophosphate pathway, inhibiting Ca2+ channels, and activating K+ channels. The hypotensive effects of GCE were evaluated in spontaneously hypertensive rats (SHRs). The SHRs were randomly divided into a control group and orally administered GCE group (100 or 300 mg/kg). The systolic and diastolic blood pressure decreased significantly by -19.47 ± 4.58% and -31.14 ± 7.66% in the GCE 100 mg/kg group, and -21.64 ± 2.40% and -31.91 ± 5.75% in the GCE 300 mg/kg group at 4 h after administration. Considering its vasorelaxant and hypotensive effects, our results indicate that GCE may be a valuable solution for the control of hypertension. However, further studies on the long-term administration and toxicity of GCE are required.

Propolis in the management of cardiovascular disease

BACKGROUND

Propolis is a resinous compound that is obtained from honey bees. It consists of numerous chemical constituents that impart different therapeutic action. The heart is the core of the body and cardiovascular disease (CVD) is a burden for the human being. This article emphasizes how propolis is fruitful in the management of various CVDs.

SCOPE AND APPROACH

This review focuses on how various constituents of the propolis (such as terpenes, flavonoids, phenolics, etc.) impart cardio protective actions.

KEY FINDING AND CONCLUSION

With the support of various clinical trials and research outcomes, it was concluded that propolis owns niche cardio protective properties that can be a boon for various cardiac problems (both in preventive and therapeutic action) such as atherosclerosis, excessive angiogenesis, hypertension, and many more.

Immunological Profile and Markers of Endothelial Dysfunction in Elderly Patients with Cognitive Impairments

The process of aging is accompanied by a dynamic restructuring of the immune response, a phenomenon known as immunosenescence. Further, damage to the endothelium can be both a cause and a consequence of many diseases, especially in elderly people. The purpose of this study was to carry out immunological and biochemical profiling of elderly people with acute ischemic stroke (AIS), chronic cerebral circulation insufficiency (CCCI), prediabetes or newly diagnosed type II diabetes mellitus (DM), and subcortical ischemic vascular dementia (SIVD). Socio-demographic, lifestyle, and cognitive data were obtained. Biochemical, hematological, and immunological analyses were carried out, and extracellular vesicles (EVs) with endothelial CD markers were assessed. The greatest number of significant deviations from conditionally healthy donors (HDs) of the same age were registered in the SIVD group, a total of 20, of which 12 were specific and six were non-specific but with maximal differences (as compared to the other three groups) from the HDs group. The non-specific deviations were for the MOCA (Montreal Cognitive Impairment Scale), the MMSE (Mini Mental State Examination) and life satisfaction self-assessment scores, a decrease of albumin levels, and ADAMTS13 (a Disintegrin and Metalloproteinase with a Thrombospondin Type 1 motif, member 13) activity, and an increase of the VWF (von Willebrand factor) level. Considering the significant changes in immunological parameters (mostly Th17-like cells) and endothelial CD markers (CD144 and CD34), vascular repair was impaired to the greatest extent in the DM group. The AIS patients showed 12 significant deviations from the HD controls, including three specific to this group. These were high NEFAs (non-esterified fatty acids) and CD31 and CD147 markers of EVs. The lowest number of deviations were registered in the CCCI group, nine in total. There were significant changes from the HD controls with no specifics to this group, and just one non-specific with a maximal difference from the control parameters, which was α1-AGP (alpha 1 acid glycoprotein, orosomucoid). Besides the DM patients, impairments of vascular repair were also registered in the CCCI and AIS patients, with a complete absence of such in patients with dementia (SIVD group). On the other hand, microvascular damage seemed to be maximal in the latter group, considering the biochemical indicators VWF and ADAMTS13. In the DM patients, a maximum immune response was registered, mainly with Th17-like cells. In the CCCI group, the reaction was not as pronounced compared to other groups of patients, which may indicate the initial stages and/or compensatory nature of organic changes (remodeling). At the same time, immunological and biochemical deviations in SIVD patients indicated a persistent remodeling in microvessels, chronic inflammation, and a significant decrease in the anabolic function of the liver and other tissues. The data obtained support two interrelated assumptions. Taking into account the primary biochemical factors that trigger the pathological processes associated with vascular pathology and related diseases, the first assumption is that purine degradation in skeletal muscle may be a major factor in the production of uric acid, followed by its production by non-muscle cells, the main of which are endothelial cells. Another assumption is that therapeutic factors that increase the levels of endothelial progenitor cells may have a therapeutic effect in reducing the risk of cerebrovascular disease and related neurodegenerative diseases.

Endothelial Dysfunction and Heart Failure with Preserved Ejection Fraction-An Updated Review of the Literature

Heart failure (HF) is a clinical syndrome consisting of typical symptoms and signs due to structural and/or functional abnormalities of the heart, resulting in elevated intracardiac pressures and/or inadequate cardiac output. The vascular system plays a crucial role in the development and progression of HF regardless of ejection fraction, with endothelial dysfunction (ED) as one of the principal features of HF. The main ED manifestations (i.e., impaired endothelium-dependent vasodilation, increased oxidative stress, chronic inflammation, leukocyte adhesion, and endothelial cell senescence) affect the systemic and pulmonary haemodynamic and the renal and coronary circulation. The present review is aimed to discuss the contribution of ED to HF pathophysiology-in particular, HF with preserved ejection fraction-ED role in HF patients, and the possible effects of pharmacological and non-pharmacological approaches. For this purpose, relevant data from a literature search (PubMed, Scopus, EMBASE, and Medline) were reviewed. As a result, ED, assessed via venous occlusion plethysmography or flow-mediated dilation, was shown to be independently associated with poor outcomes in HF patients (e.g., mortality, cardiovascular events, and hospitalization due to worsening HF). In addition, SGLT2 inhibitors, endothelin antagonists, endothelial nitric oxide synthase cofactors, antioxidants, and exercise training were shown to positively modulate ED in HF. Despite the need for future research to better clarify the role of the vascular endothelium in HF, ED represents an interesting and promising potential therapeutic target.

Phosphodiesterase-5 inhibitors tadalafil and sildenafil potentiate nitrergic-nerve mediated relaxations in the bladder vasculature

Recent studies suggest that lower urinary tract dysfunction may arise due to changes in local perfusion. Phosphodiesterase-5 inhibitors can improve urinary bladder blood flow, although the local mechanisms have not been fully elucidated. The aim was to pharmacologically characterise the vascular supply to the bladder and determine the mechanisms underlying the effects of the phosphodiesterase-5 inhibitors tadalafil and sildenafil. Responses of isolated rings of porcine superior vesical arteries to electrical field stimulation (EFS) were measured in the absence and presence of inhibitors of key neurotransmitter systems. Vasodilation responses to nitric oxide (NO) donors were also recorded, and the effects of phosphodiesterase-5 inhibitors on all responses determined. EFS caused biphasic responses with an initial vasoconstriction and a slower developing vasodilation. Vasoconstriction was mediated by ATP (55%) and noradrenaline (45%) release, whilst vasodilation was reduced by L-NNA (100 μM) (80%) and propranolol (1 μM) (20%). The nitrergic component was inhibited (81%) by L-NPA, a selective inhibitor of neuronal nitric oxide synthase (nNOS). Endothelial removal did not affect vasodilation. Tadalafil and sildenafil depressed noradrenaline-evoked vasoconstriction (by 26.8% and 35.5% respectively, P < 0.01), enhanced vasodilation to EFS (by 27.8% and 51.8% respectively, p < 0.01) and enhanced responses to NO donors nitroprusside, SIN-1, and SNAP, increasing pIC50 values (P < 0.01), without affecting maximal responses. In conclusion, neuronal NOS has a predominant role in regulating vascular tone of the porcine superior vesical artery and potentiation of nNO-mediated vasodilation is the primary mechanism underlying effects of phosphodiesterase-5 inhibitors in the bladder vasculature.

Mechanistic exploration of Yiqi Liangxue Shengji prescription on restenosis after balloon injury by integrating metabolomics with network pharmacology

CONTEXT

Yiqi Liangxue Shengji prescription (YQLXSJ) is a traditional Chinese medicine (TCM) formula that has long been used for treatment after percutaneous coronary intervention (PCI).

OBJECTIVE

To investigate the putative pharmacological mechanism of YQLXSJ on restenosis through an integrated approach utilizing metabolomics and network pharmacology.

MATERIALS AND METHODS

Forty male Sprague-Dawley rats were divided into sham, model, YQLXSJ, and positive groups. YQLXSJ group received the treatment of YQLXSJ (6 g/kg/d, i.g.) and the positive group was treated with atorvastatin (2 mg/kg/d, i.g.). After 4 weeks, the improvement in intimal hyperplasia was evaluated by ultrasound, H&E staining, and immunofluorescence. UPLC-MS/MS technology was utilized to screen the differential metabolites. Network pharmacology was conducted using TCMSP, GeneCards, and Metascape, etc., in combination with metabolomics. Eventually, the core targets were acquired and validated.

RESULTS

Compared to models, YQLXSJ exhibited decreased intima-media thickness on ultrasound (0.23 ± 0.02 mm vs. 0.20 ± 0.01 mm, p < 0.01) and reduced intima thickness by H&E (30.12 ± 6.05 μm vs. 14.32 ± 1.37 μm, p < 0.01). We identified 18 differential metabolites and 5 core targets such as inducible nitric oxide synthase (NOS2), endothelial nitric oxide synthase (NOS3), vascular endothelial growth factor-A (VEGFA), ornithine decarboxylase-1 (ODC1) and group IIA secretory phospholipase A2 (PLA2G2A). These targets were further confirmed by molecular docking and ELISA.

DISCUSSION AND CONCLUSIONS

This study confirms the effects of YQLXSJ on restenosis and reveals some biomarkers. TCM has great potential in the prevention and treatment of restenosis by improving metabolic disorders.

Cracking the Endothelial Calcium (Ca2+) Code: A Matter of Timing and Spacing

A monolayer of endothelial cells lines the innermost surface of all blood vessels, thereby coming into close contact with every region of the body and perceiving signals deriving from both the bloodstream and parenchymal tissues. An increase in intracellular Ca2+ concentration ([Ca2+]i) is the main mechanism whereby vascular endothelial cells integrate the information conveyed by local and circulating cues. Herein, we describe the dynamics and spatial distribution of endothelial Ca2+ signals to understand how an array of spatially restricted (at both the subcellular and cellular levels) Ca2+ signals is exploited by the vascular intima to fulfill this complex task. We then illustrate how local endothelial Ca2+ signals affect the most appropriate vascular function and are integrated to transmit this information to more distant sites to maintain cardiovascular homeostasis. Vasorelaxation and sprouting angiogenesis were selected as an example of functions that are finely tuned by the variable spatio-temporal profile endothelial Ca2+ signals. We further highlighted how distinct Ca2+ signatures regulate the different phases of vasculogenesis, i.e., proliferation and migration, in circulating endothelial precursors.

Further insight into systemic sclerosis from the vasculopathy perspective

Systemic sclerosis (SSc) is an autoimmune disease characterized by immune dysfunction, vascular system dysfunction, and tissue fibrosis. Vascular injury, vascular remodeling, and endothelial dysfunction are the hallmark pathological changes of the disease. In the early stages of SSc development, endothelial cell injury and apoptosis can lead to vascular and perivascular inflammation, oxidative stress, and tissue hypoxia, which can cause clinical manifestations in various organs from the skin to the parenchymal organs. Early diagnosis and rational treatment can improve patient survival and quality of life. Ancillary examinations such as nailfold capillaroscopy as well as optical coherence tomography can help early detect vascular injury in SSc patients. Studies targeting the mechanisms of vascular lesions will provide new perspectives for treatment of SSc.

Hypertension and Dyslipidemia: the Two Partners in Endothelium-Related Crime

PURPOSE OF REVIEW

The goal of this article is to characterize the endothelium's role in the development of hypertension and dyslipidemia and to point out promising therapeutic directions.

RECENT FINDINGS

Dyslipidemia may facilitate the development of hypertension, whereas the collaboration of these two silent killers potentiates the risk of atherosclerosis. The common pathophysiological denominator for hypertension and dyslipidemia is endothelial cell dysfunction, which manifests as dysregulation of homeostasis, redox balance, vascular tone, inflammation, and thrombosis. Treatment focused on mediators acting in these processes might be groundbreaking. Metabolomic research on hypertension and dyslipidemia has revealed new therapeutic targets. State-of-the-art solutions integrating interview, clinical examination, innovative imaging, and omics profiles along with artificial intelligence have been already shown to improve patients' risk stratification and treatment. Pathomechanisms underlying hypertension and dyslipidemia take place in the endothelium. Novel approaches involving endothelial biomarkers and bioinformatics advances could open new perspectives in patient management.

The Role of Polymorphism in the Endothelial Homeostasis and Vitamin D Metabolism Genes in the Severity of Coronary Artery Disease

Coronary artery disease (CAD) remains one of the leading causes of cardiovascular morbidity and mortality worldwide. The maintenance of endothelial homeostasis and vitamin D metabolism play an important role in CAD pathogenesis. This study aimed to determine the association of endothelial homeostasis and vitamin D metabolism gene polymorphism with CAD severity. A total of 224 low-risk patients (SYNTAX score ≤ 31) and 36 high-risk patients (SYNTAX score > 31) were recruited for this study. The serum level of E-, L- and P-selectins; endothelin; eNOS; 25OH; and 1.25-dihydroxy vitamin D was measured using an enzyme-linked immunosorbent assay (ELISA). Polymorphic variants in SELE, SELP, SELPLG, END1, NOS3, VDR and GC were analyzed using a polymerase chain reaction (PCR). We found no differences in the serum levels of the studied markers between high- and low-risk patients. Three polymorphic variants associated with CAD severity were discovered: END1 rs3087459, END1 rs5370 and GC rs2298849 in the log-additive model. Moreover, we discovered a significantly decreased serum level of 1.25-dihydroxy vitamin D in high-risk CAD patients with the A/A-A/G genotypes of the rs2228570 polymorphism of the VDR gene, the A/A genotype of the rs7041 polymorphism of the GC gene and the A/A genotype of the rs2298849 polymorphism of the GC gene.

Maximakinin reduced intracellular Ca2+ level in vascular smooth muscle cells through AMPK/ERK1/2 signaling pathways

We detect the antihypertensive effects of maximakinin (MK) on renal hypertensive rats (RHRs) and further research the influence of MK on vascular smooth muscle cells (VSMCs) to explore its hypotensive mechanism. The effects of MK on arterial blood pressure were observed in RHRs. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assays were performed to detect the effect of MK on VSMC viability. Western blot and flow cytometry were used to investigate the influence of MK on intracellular Ca2+ levels and protein expression changes in VSMCs. In addition, specific protein inhibitors were applied to confirm the involvement of Ca2+-related signaling pathways induced by MK in VSMCs. MK showed a more significant antihypertensive effect than bradykinin in RHRs. MK significantly decreased intracellular Ca2+ concentrations. Furthermore, MK significantly induced the phosphorylation of signaling molecules, including extracellular signal-regulated kinase 1/2 (ERK1/2), P38, AMP-activated protein kinase (AMPK) and Akt in VSMCs. Moreover, only ERK1/2 inhibitor U0126 and AMPK inhibitor Compound C completely restored the decreased intracellular Ca2+ level induced by MK, and further research demonstrated that AMPK functioned upstream of ERK1/2 following exposure to MK. Finally, HOE-140, an inhibitor of the bradykinin B2 receptors (B2Rs), was applied to investigate the potential targets of MK in VSMCs. HOE-140 significantly blocked the AMPK/ERK1/2 pathway induced by MK, suggesting that the B2Rs might play an important role in MK-induced AMPK and ERK1/2 activation. MK significantly reduces blood pressure in RHRs. MK exerts its antihypertensive effect by activating the B2Rs and downstream AMPK/ERK1/2 pathways, leading to significantly reduced Ca2+ levels in VSMCs.

Effects of miR-33 Deficiency on Metabolic and Cardiovascular Diseases: Implications for Therapeutic Intervention

MicroRNAs (miRNAs) are small noncoding RNAs that post-transcriptionally inhibit gene expression. These small molecules are involved in several biological conditions such as inflammation, cell growth and proliferation, and regulation of energy metabolism. In the context of metabolic and cardiovascular diseases, miR-33 is of particular interest as it has been implicated in the regulation of lipid and glucose metabolism. This miRNA is located in introns harboured in the genes encoding sterol regulatory element-binding protein (SREBP)-1 and SREBP-2, which are key transcription factors involved in lipid biosynthesis and cholesterol efflux. This review outlines the role of miR-33 in a range of metabolic and cardiovascular pathologies, such as dyslipidaemia, nonalcoholic fatty liver disease (NAFLD), obesity, diabetes, atherosclerosis, and abdominal aortic aneurysm (AAA), and it provides discussion about the effectiveness of miR-33 deficiency as a possible therapeutic strategy to prevent the development of these diseases.

Atherosclerosis treatment with nanoagent: potential targets, stimulus signals and drug delivery mechanisms

Cardiovascular disease (CVDs) is the first killer of human health, and it caused up at least 31% of global deaths. Atherosclerosis is one of the main reasons caused CVDs. Oral drug therapy with statins and other lipid-regulating drugs is the conventional treatment strategies for atherosclerosis. However, conventional therapeutic strategies are constrained by low drug utilization and non-target organ injury problems. Micro-nano materials, including particles, liposomes, micelles and bubbles, have been developed as the revolutionized tools for CVDs detection and drug delivery, specifically atherosclerotic targeting treatment. Furthermore, the micro-nano materials also could be designed to intelligently and responsive targeting drug delivering, and then become a promising tool to achieve atherosclerosis precision treatment. This work reviewed the advances in atherosclerosis nanotherapy, including the materials carriers, target sites, responsive model and treatment results. These nanoagents precisely delivery the therapeutic agents to the target atherosclerosis sites, and intelligent and precise release of drugs, which could minimize the potential adverse effects and be more effective in atherosclerosis lesion.

Roles and mechanism of IL-11 in vascular diseases

Vascular diseases are the leading cause of morbidity and mortality worldwide. Therefore, effective treatment strategies that can reduce the risk of vascular diseases are urgently needed. The relationship between Interleukin-11 (IL-11) and development of vascular diseases has gained increasing attention. IL-11, a target for therapeutic research, was initially thought to participate in stimulating platelet production. Additional research concluded that IL-11 is effective in treating several vascular diseases. However, the function and mechanism of IL-11 in these diseases remain unknown. This review summarizes IL-11 expression, function, and signal transduction mechanism. This study also focuses on the role of IL-11 in coronary artery disease, hypertension, pulmonary hypertension, cerebrovascular disease, aortic disease, and other vascular diseases and its potential as a therapeutic target. Consequently, this study provides new insight into the clinical diagnosis and treatment of vascular diseases.

The tissue-specific transcriptional landscape underlines the involvement of endothelial cells in health and disease

Endothelial cells (ECs) that line vascular and lymphatic vessels are being increasingly recognized as important to organ function in health and disease. ECs participate not only in the trafficking of gases, metabolites, and cells between the bloodstream and tissues but also in the angiocrine-based induction of heterogeneous parenchymal cells, which are unique to their specific tissue functions. The molecular mechanisms regulating EC heterogeneity between and within different tissues are modeled during embryogenesis and become fully established in adults. Any changes in adult tissue homeostasis induced by aging, stress conditions, and various noxae may reshape EC heterogeneity and induce specific transcriptional features that condition a functional phenotype. Heterogeneity is sustained via specific genetic programs organized through the combinatory effects of a discrete number of transcription factors (TFs) that, at the single tissue-level, constitute dynamic networks that are post-transcriptionally and epigenetically regulated. This review is focused on outlining the TF-based networks involved in EC specialization and physiological and pathological stressors thought to modify their architecture.

Endothelial KCa channels: Novel targets to reduce atherosclerosis-driven vascular dysfunction

Elevated levels of cholesterol in the blood can induce endothelial dysfunction, a condition characterized by impaired nitric oxide production and decreased vasodilatory capacity. Endothelial dysfunction can promote vascular disease, such as atherosclerosis, where macrophages accumulate in the vascular intima and fatty plaques form that impair normal blood flow in conduit arteries. Current pharmacological strategies to treat atherosclerosis mostly focus on lipid lowering to prevent high levels of plasma cholesterol that induce endothelial dysfunction and atherosclerosis. While this approach is effective for most patients with atherosclerosis, for some, lipid lowering is not enough to reduce their cardiovascular risk factors associated with atherosclerosis (e.g., hypertension, cardiac dysfunction, stroke, etc.). For such patients, additional strategies targeted at reducing endothelial dysfunction may be beneficial. One novel strategy to restore endothelial function and mitigate atherosclerosis risk is to enhance the activity of Ca2+-activated K+ (KCa) channels in the endothelium with positive gating modulator drugs. Here, we review the mechanism of action of these small molecules and discuss their ability to improve endothelial function. We then explore how this strategy could mitigate endothelial dysfunction in the context of atherosclerosis by examining how KCa modulators can improve cardiovascular function in other settings, such as aging and type 2 diabetes. Finally, we consider questions that will need to be addressed to determine whether KCa channel activation could be used as a long-term add-on to lipid lowering to augment atherosclerosis treatment, particularly in patients where lipid-lowering is not adequate to improve their cardiovascular health.

Effect of Remote Ischaemic Preconditioning on Perioperative Endothelial Dysfunction in Non-Cardiac Surgery: A Randomised Clinical Trial

Endothelial dysfunction result from inflammation and excessive production of reactive oxygen species as part of the surgical stress response. Remote ischemic preconditioning (RIPC) potentially exerts anti-oxidative and anti-inflammatory properties, which might stabilise the endothelial function after non-cardiac surgery. This was a single centre randomised clinical trial including 60 patients undergoing sub-acute laparoscopic cholecystectomy due to acute cholecystitis. Patients were randomised to RIPC or control. The RIPC procedure consisted of four cycles of five minutes of ischaemia and reperfusion of one upper extremity. Endothelial function was assessed as the reactive hyperaemia index (RHI) and circulating biomarkers of nitric oxide (NO) bioavailability (L-arginine, asymmetric dimethylarginine (ADMA), L-arginine/ADMA ratio, tetra- and dihydrobiopterin (BH4 and BH2), and total plasma biopterin) preoperative, 2–4 h after surgery and 24 h after surgery. RHI did not differ between the groups (p = 0.07). Neither did levels of circulating biomarkers of NO bioavailability change in response to RIPC. L-arginine and L-arginine/ADMA ratio was suppressed preoperatively and increased 24 h after surgery (p < 0.001). The BH4/BH2-ratio had a high preoperative level, decreased 2–4 h after surgery and remained low 24 h after surgery (p = 0.01). RIPC did not influence endothelial function or markers of NO bioavailability until 24 h after sub-acute laparoscopic cholecystectomy. In response to surgery, markers of NO bioavailability increased, and oxidative stress decreased. These findings support that a minimally invasive removal of the inflamed gallbladder countereffects reduced markers of NO bioavailability and increased oxidative stress caused by acute cholecystitis.

Endoplasmic Reticulum Stress and Renin-Angiotensin System Crosstalk in Endothelial Dysfunction

BACKGROUND

Vascular endothelial dysfunction (VED) significantly results in catastrophic cardiovascular diseases with multiple aetiologies. Variations in vasoactive peptides, including angiotensin II and endothelin 1, and metabolic perturbations like hyperglycaemia, altered insulin signalling, and homocysteine levels result in pathogenic signalling cascades, which ultimately lead to VED. Endoplasmic reticulum (ER) stress reduces nitric oxide availability, causes aberrant angiogenesis, and enhances oxidative stress pathways, consequently promoting endothelial dysfunction. Moreover, the renin-angiotensin system (RAS) has widely been acknowledged to impact angiogenesis, endothelial repair and inflammation. Interestingly, experimental studies at the preclinical level indicate a possible pathological link between the two pathways in the development of VED. Furthermore, pharmacological modulation of ER stress ameliorates angiotensin-II mediated VED as well as RAS intervention either through inhibition of the pressor arm or enhancement of the depressor arm of RAS, mitigating ER stress-induced endothelial dysfunction and thus emphasizing a vital crosstalk.

CONCLUSION

Deciphering the pathway overlap between RAS and ER stress may open potential therapeutic avenues to combat endothelial dysfunction and associated diseases. Several studies suggest that alteration in a component of RAS may induce ER stress or induction of ER stress may modulate the RAS components. In this review, we intend to elaborate on the crosstalk of ER stress and RAS in the pathophysiology of VED.

Clinical Evidence on the Potential Beneficial Effects of Probiotics and Prebiotics in Cardiovascular Disease

The 'gut microbiome'-the hundreds of trillions of bacteria in the human gastrointestinal tract-serves several functions. The gut microbiome includes all the microorganisms, bacteria, viruses, protozoa, and fungi in the gastrointestinal tract and their genetic material. It helps digest indigestible foods and produces nutrients. Through the metabolism of sugars and proteins, it helps the intestinal barrier, the immune system, and metabolism. Some bacteria, such as those in the gut microbiome, cause disease, but others are essential to our health. These "good" microbes protect us from pathogens. Numerous studies have linked an unhealthy gut microbiome to obesity, insulin resistance, depression, and cardiometabolic risk factors. To maximize probiotic benefits in each case, knowledge of probiotic bacterial strains and how to consume them should be increased. This study aims to examine the benefits of probiotic and prebiotic organisms on cardiovascular health, specifically on heart disease, coronary heart disease, stroke, and hypertension. To complete the research, a literature review was conducted by gathering clinical studies and data. The clinical evidence demonstrates the beneficial effect of probiotics and prebiotic microorganisms on the gut microbiome, which has multiple benefits for overall health and especially for cardiovascular diseases.

A role for endothelial NMDA receptors in the pathophysiology of schizophrenia

Numerous genetic and postmortem studies link N-methyl-d-aspartate receptor (NMDAR) dysfunction with schizophrenia, forming the basis of the popular glutamate hypothesis. Neuronal NMDAR abnormalities are consistently reported from both basic and clinical experiments, however, non-neuronal cells also contain NMDARs, and are rarely, if ever, considered in the discussion of glutamate action in schizophrenia. We offer an examination of recent discoveries elucidating the actions and consequences of NMDAR activation in the neuroendothelium. While there has been mixed literature regarding blood flow alterations in the schizophrenia brain, in this review, we posit that some common findings may be explained by neuroendothelial NMDAR dysfunction. In particular, we emphasize that endothelial NMDARs are key mediators of neurovascular coupling, where increased neuronal activity leads to increased blood flow. Based on the broad conclusions that hypoperfusion is a neuroanatomical finding in schizophrenia, we discuss potential mechanisms by which endothelial NMDARs contribute to this disorder. We propose that endothelial NMDAR dysfunction can be a primary cause of neurovascular abnormalities in schizophrenia. Importantly, functional MRI studies using BOLD signal as a proxy for neuron activity should be considered in a new light if neurovascular coupling is impaired in schizophrenia. This review is the first to propose that NMDARs in non-excitable cells play a role in schizophrenia.

Circulating microparticles are increased amongst people presenting with HIV and advanced immune suppression in Malawi and correlate closely with arterial stiffness: a nested case control study

Background: We aim to investigate whether circulating microparticle (CMPs) subsets were raised amongst people presenting with a new diagnosis of HIV and advanced immune suppression in Malawi, and whether they associated with arterial stiffness. Methods: Microparticle characterisation and carotid femoral Pulse Wave Velocity (cfPWV) were carried out in a cohort of adults with a new HIV diagnosis and CD4 <100 cells/µL at 2 weeks post ART initiation. HIV uninfected controls were matched on age, systolic BP and diastolic BP in a 1:1 ratio.  Circulating microparticles were identified from platelet poor plasma and stained for endothelial, leucocyte, monocyte and platelet markers. Results: The median (IQ) total CMP count for 71 participants was 1 log higher in HIV compared to those without (p<0.0001) and was associated with arterial stiffness (spearman rho 0.47, p<0.001). In adjusted analysis, every log increase in circulating particles showed a 20% increase in cfPWV (95% CI 4 - 40%, p=0.02). In terms of subsets, endothelial and platelet derived microparticles were most strongly associated with HIV. Endothelial derived E-selectin+ CMPs were 1.3log-fold higher and platelet derived CD42a+ CMPs were 1.4log-fold higher (both p<0.0001). Endothelial and platelet derived CMPs also correlated most closely with arterial stiffness [spearman rho: E-selectin+ 0.57 and CD42a 0.56, both p<0.0001). Conclusions: Circulating microparticles associate strongly with arterial stiffness among PLWH in Malawi. Endothelial and platelet microparticles are the predominant cell origin types, indicating that platelet driven endothelial dysfunction pathways warrant further investigation in HIV associated arterial stiffness.

Recent advances of natural and bioengineered extracellular vesicles and their application in vascular regeneration

The progression of cardiovascular diseases such as atherosclerosis and myocardial infarction leads to serious vascular injury, highlighting the urgent need for targeted regenerative therapy. Extracellular vesicles (EVs) composed of a lipid bilayer containing nuclear and cytosolic materials are relevant to the progression of cardiovascular diseases. Moreover, EVs can deliver bioactive cargo in pathological cardiovascular and regulate the biological function of recipient cells, such as inflammation, proliferation, angiogenesis and polarization. However, because the targeting and bioactivity of natural EVs are subject to several limitations, bioengineered EVs have achieved wide advancements in biomedicine. Bioengineered EVs involve three main ways to acquire including (i) modification of the EVs after isolation; (ii) modification of producer cells before EVs’ isolation; (iii) synthesize EVs using natural or modified cell membranes, and encapsulating drugs or bioactive molecules into EVs. In this review, we first summarize the cardiovascular injury-related disease and describe the role of different cells and EVs in vascular regeneration. We also discuss the application of bioengineered EVs from different producer cells to cardiovascular diseases. Finally, we summarize the surface modification on EVs which can specifically target abnormal cells in injured vascular.

Insulin Resistance Is Cheerfully Hitched with Hypertension

Cardiovascular diseases and type 2 diabetes mellitus (T2DM) have risen steadily worldwide, particularly in low-income and developing countries. In the last hundred years, deaths caused by cardiovascular diseases increased rapidly to 35-40%, becoming the most common cause of mortality worldwide. Cardiovascular disease is the leading cause of morbidity and mortality in type 2 diabetes mellitus (T2DM), which is aggravated by hypertension. Hypertension and diabetes are closely interlinked since they have similar risk factors such as endothelial dysfunction, vascular inflammation, arterial remodeling, atherosclerosis, dyslipidemia, and obesity. Patients with high blood pressure often show insulin resistance and have a higher risk of developing diabetes than normotensive individuals. It has been observed that over the last 30 years, the prevalence of insulin resistance (IR) has increased significantly. Accordingly, hypertension and insulin resistance are strongly related to an increased risk of impaired glucose tolerance, diabetes, cardiovascular diseases (CVD), and endocrine disorders. Common mechanisms, for instance, upregulation of the renin-angiotensin-aldosterone system, oxidative stress, inflammation, and activation of the immune system, possibly have a role in the association between diabetes and hypertension. Altogether these abnormalities significantly increase the risk of developing type 2 diabetes.

Isolation of Mouse Aortic RNA for Transcriptomics

Aging is associated with alterations in the arterial wall that promote vascular disease development and its clinical manifestations, including myocardial infarction, stroke, and arterial dissection. The arterial wall is comprised of three layers, intima, media and adventitia, each with distinct cellular composition and function, which can therefore contribute differently to vascular disease initiation and progression. Hence, studying transcriptomic alterations, either in the entire arterial wall or separately in the three arterial layers, can aid in disentangling the etiopathology of vascular disease and thus pave the way for innovative treatments. This chapter describes protocols for total RNA extraction from complete mouse aorta and separately from intima, media, and adventitia layers for subsequent transcriptomic analysis.

TFPI2 suppresses the interaction of TGF-β2 pathway regulators to promote endothelial-mesenchymal transition in diabetic nephropathy

Endothelial–mesenchymal transition (EndMT) is an important source of myofibroblasts, but also contributes to the progression of diabetic nephropathy (DN). By several differential gene expression analyses from the Gene Expression Omnibus (GEO) database, the tissue factor pathway inhibitor 2 (TFPI2) gene, known as a tumor suppressor, was shown to be dysregulated in DN; however, the potential role and regulatory mechanism of TFPI2 in DN are unclear. Here, we found abnormal upregulation of TFPI2 in the renal cortex of diabetic mice, accompanied by impaired renal function. We also injected a single dose of adeno-associated virus (AAV)2 carrying shRNA targeting TFPI2 intravenously into these mice and found that knockdown of TFPI2 improved renal function and reduced renal fibrosis and cell apoptosis in experimental DN. Furthermore, hyperglycemia-induced EndMT was inhibited in the absence of TFPI2, as evidenced by increased expression of endothelial markers (VE-cadherin and CD31) and decreased expression of mesenchymal markers (α-SMA, desmin, and FSP-1). To further explore the mechanism in vitro, human renal glomerular endothelial cells (hRGECs) were incubated in the presence of high glucose or transforming growth factor beta (TGF-β)2. TFPI2 deficiency inhibited high glucose-induced cell apoptosis and TGF-β2-induced EndMT in hRGECs, while overexpression of TFPI2 had the opposite effects. Importantly, TGF-β2 is a crucial driver of EndMT, and we found that TFPI2 promoted TGF-β2/Smad signaling activation by interferring the interaction of TGF-β pathway regulators (SMURF2 with SMAD7). Our results show that TFPI2 regulates EndMT and the TGF-β2 signaling pathway and is a potential promoter of DN pathogenesis.

Effects of Pharmacological Inhibitors of NADPH Oxidase on Myogenic Contractility and Evoked Vasoactive Responses in Rat Resistance Arteries

Reactive oxygen species (ROS), such as superoxide anions and hydrogen peroxide, are reported to contribute to the dynamic regulation of contractility in various arterial preparations, however, the situation in pressurized, myogenically active resistance arteries is much less clear. In the present study, we have utilized established pharmacological inhibitors of NADPH oxidase activity to examine the potential contribution of ROS to intrinsic myogenic contractility in adult Sprague–Dawley rat resistance arteries and responses to vasoactive agents acting via the endothelium (i.e., acetylcholine, SKA-31) or smooth muscle (i.e., sodium nitroprusside, phenylephrine). In cannulated and pressurized cremaster skeletal muscle and middle cerebral arteries, the NOX inhibitors 2-acetylphenothiazine (2-APT) and VAS2870, selective for NOX1 and NOX2, respectively, evoked concentration-dependent inhibition of basal myogenic tone in a reversible and irreversible manner, respectively, whereas the non-selective inhibitor apocynin augmented myogenic contractility. The vasodilatory actions of 2-APT and VAS2870 occurred primarily via the vascular endothelium and smooth muscle, respectively. Functional responses to established endothelium-dependent and –independent vasoactive agents were largely unaltered in the presence of either 2-APT or apocynin. In cremaster arteries from Type 2 Diabetic (T2D) Goto-Kakizaki rats with endothelial dysfunction, treatment with either 2-APT or apocynin did not modify stimulus-evoked vasoactive responses, but did affect basal myogenic tone. These same NOX inhibitors produced robust inhibition of total NADPH oxidase activity in aortic tissue homogenates from control and T2D rats, and NOX isozymes 1, 2 and 4, along with superoxide dismutase 1, were detected by qPCR in cremaster arteries and aorta from both species. Based on the diverse effects that we observed for established, chemically distinct NOX inhibitors, the functional contribution of vascular NADPH oxidase activity to stimulus-evoked vasoactive signaling in myogenically active, small resistance arteries remains unclear.

Serum Calprotectin Level as an Inflammatory Marker in Newly Diagnosed Hypertensive Patients

Background

Hypertension is one of the leading causes of cardiovascular mortality. Although the pathogenetic process involved is not yet fully understood, the disease involves endothelial damage and inflammation. Calprotectin is an inflammatory marker that rises in parallel with disease activity in conditions such as systemic inflammatory diseases, infection, and atherosclerosis. The purpose of this study was to evaluate inflammation through serum calprotectin levels in newly diagnosed primary hypertension patients.

Methods

Forty-nine newly diagnosed hypertensive patients and 38 healthy adults were included in the study. Patients' office blood pressure values, biochemical findings, and demographic characteristics were recorded. Serum calprotectin levels were measured using ELISA. Parameters affecting serum calprotectin levels and determinants of hypertension were evaluated.

Results

Serum calprotectin levels were 242.8 (72.4–524) ng/mL in the control group and 112.6 (67.4–389.8) ng/mL in the hypertensive patient group, the difference being statistically significant (p=0.001). There was no correlation between serum calprotectin levels and other parameters (blood pressure values, age, gender, serum creatinine, uric acid, and calcium levels) in the hypertensive group. A lower serum calprotectin level was found to be independently related to hypertension (β = −0.009, p=0.005). Serum calprotectin at a cutoff level of 128.6 ng/mL differentiated hypertensives from healthy controls with a sensitivity of 69.4% and specificity of 68.4% (AUC = 0.767).

Conclusions

The results of this study were the opposite of our hypothesis that a higher calprotectin level may reflect subclinical endothelial damage in newly diagnosed hypertensive patients. Further comparative studies involving patients at different stages of hypertension may contribute to clarifying the relationship between calprotectin and hypertension. We conclude that molecular studies seem essential for understanding the place of calprotectin in hypertension-associated inflammation, a complex process.

Management of Endothelial Dysfunction in Systemic Sclerosis: Current and Developing Strategies

Systemic Sclerosis (SSc) is an autoimmune disease marked by dysregulation of the immune system, tissue fibrosis and dysfunction of the vasculature. Vascular damage, remodeling and inadequate endothelial repair are hallmarks of the disease. Since early stages of SSc, damage and apoptosis of endothelial cells (ECs) can lead to perivascular inflammation, oxidative stress and tissue hypoxia, resulting in multiple clinical manifestations. Raynaud's phenomenon, edematous puffy hands, digital ulcers, pulmonary artery hypertension, erectile dysfunction, scleroderma renal crisis and heart involvement severely affect quality of life and survival. Understanding pathogenic aspects and biomarkers that reflect endothelial damage in SSc is essential to guide therapeutic interventions. Treatment approaches described for SSc-associated vasculopathy include pharmacological options to improve blood flow and tissue perfusion and, more recently, cellular therapy to enhance endothelial repair, promote angiogenesis and heal injuries. This mini-review examines the current knowledge on cellular and molecular aspects of SSc vasculopathy, as well as established and developing therapeutic approaches for improving the vascular compartment.

Resistance training increases insulin-induced vasodilation in the mesenteric artery of healthy rats

This study evaluated the ability of resistance training (RT) of moderate intensity to promote vascular changes in insulin-induced vasodilation in healthy animals. Wistar rats were divided into two groups: control (CON) and trained (eight weeks of training, performing 3 sets with 10 repetitions at 60% of maximum intensity). Forty-eight hours after the last session of the RT, the animals were sacrificed and vascular reactivity to insulin in the absence and presence of LY294002 (phosphatidylinositol 3-kinase inhibitors (PI3K), L-NAME (nitric oxide synthase (NOS) inhibitors) and BQ123 (endothelin A antagonist (ET-A) receptor). In addition, phenylephrine (Phe)-induced vasoconstriction in the absence and presence of L-NAME was also evaluated. The RT group showed greater vasodilation in maximal response compared to the CON group. After PI3K inhibition, vasodilation was reduced in both groups. However, when the NOS participation was evaluated, the RT group showed contraction in relation to the CON group, which was abolished by BQ123. In addition, the RT group had an increase in nitrite levels compared to the CON group. When the Phe response was evaluated, there was a reduction in tension in the RT group compared to the CON group. The results suggest that RT improves vascular reactivity.

Circulating microparticles are increased amongst people presenting with HIV and advanced immune suppression in Malawi and correlate closely with arterial stiffness: a nested case control study

Background: We aimed to investigate whether circulating microparticle (CMPs) subsets were raised amongst people presenting with human immunodeficiency virus (HIV) and advanced immune suppression in Malawi, and whether they associated with arterial stiffness. Methods: Antiretroviral therapy (ART)-naïve adults with a new HIV diagnosis and CD4 <100 cells/µL had microparticle characterisation and carotid femoral Pulse Wave Velocity (cfPWV) at 2 weeks post ART initiation. HIV uninfected controls were matched on age, systolic blood pressure (BP) and diastolic BP in a 1:1 ratio.  Circulating microparticles were identified from platelet poor plasma and stained for endothelial, leucocyte, monocyte and platelet markers. Results: The median (IQ) total CMP count for 71 participants was 1 log higher in HIV compared to those without (p<0.0001) and was associated with arterial stiffness (spearman rho 0.47, p<0.001). In adjusted analysis, every log increase in circulating particles showed a 20% increase in cfPWV (95% confidence interval [CI] 4 - 40%, p=0.02). In terms of subsets, endothelial and platelet derived microparticles were most strongly associated with HIV. Endothelial derived E-selectin+ CMPs were 1.3log-fold higher and platelet derived CD42a+ CMPs were 1.4log-fold higher (both p<0.0001). Endothelial and platelet derived CMPs also correlated most closely with arterial stiffness (spearman rho: E-selectin+ 0.57 and CD42a 0.56, both p<0.0001). Conclusions: Circulating microparticles associate strongly with arterial stiffness among people living with HIV in Malawi. Endothelial damage and platelet microparticles are the predominant cell origin types and future translational studies could consider prioritising these pathways.

Novel function of fluvastatin in attenuating oxidized low-density lipoprotein-induced endothelial cell ferroptosis in a glutathione peroxidase4- and cystine-glutamate antiporter-dependent manner

Oxidized low-density lipoprotein (ox-LDL) induces endothelial cell apoptosis and dysfunction. Statins are drugs that are clinically used to lower serum cholesterol levels, and they have been shown to exert vascular protective effects. In the present study, human umbilical vein endothelial cells were transfected with scramble control siRNA or siRNA specific for glutathione peroxidase (GPx)4 or cystine-glutamate antiporter (xCT). MTT, Matrigel and Transwell assays were used to evaluate cell proliferation, tube formation and migration, respectively. The levels of TNF-α, IL-α, 4-hydroxynonenal, GPx4 and xCT expression were detected by western blot analysis. It was demonstrated that ox-LDL promoted cytokine production and reduced the proliferation, migration and angiogenesis of endothelial cells. It was also observed that ox-LDL decreased GPx4 and xCT expression and induced ferroptosis. Furthermore, the inhibition of ferroptosis by deferoxamine mesylate attenuated ox-LDL-induced endothelial cell dysfunction and restored ox-LDL-decreased GPx4 and xCT expression. Consistent with these results, GPx4 and xCT knockdown by siRNA transfection aggravated ox-LDL-induced endothelial cell dysfunction and inhibition of proliferation. To the best of our knowledge, the present study was the first to discover that fluvastatin may protect endothelial cells from ox-LDL-induced ferroptosis and dysfunction. Furthermore, knockdown of GPx4 and xCT expression blunted the protective effects of fluvastatin on ox-LDL-treated endothelial cells. These data indicated a novel function of fluvastatin in the protection of endothelial cells from ox-LDL-induced ferroptosis, the mechanism of which involves the regulation of GPx4 and xCT.

Reactive Oxygen Species and Endothelial Ca2+ Signaling: Brothers in Arms or Partners in Crime?

An increase in intracellular Ca²⁺ concentration ([Ca²⁺]_i) controls virtually all endothelial cell functions and is, therefore, crucial to maintain cardiovascular homeostasis. An aberrant elevation in endothelial can indeed lead to severe cardiovascular disorders. Likewise, moderate amounts of reactive oxygen species (ROS) induce intracellular Ca²⁺ signals to regulate vascular functions, while excessive ROS production may exploit dysregulated Ca²⁺ dynamics to induce endothelial injury. Herein, we survey how ROS induce endothelial Ca²⁺ signals to regulate vascular functions and, vice versa, how aberrant ROS generation may exploit the Ca²⁺ handling machinery to promote endothelial dysfunction. ROS elicit endothelial Ca²⁺ signals by regulating inositol-1,4,5-trisphosphate receptors, sarco-endoplasmic reticulum Ca²⁺-ATPase 2B, two-pore channels, store-operated Ca²⁺ entry (SOCE), and multiple isoforms of transient receptor potential (TRP) channels. ROS-induced endothelial Ca²⁺ signals regulate endothelial permeability, angiogenesis, and generation of vasorelaxing mediators and can be exploited to induce therapeutic angiogenesis, rescue neurovascular coupling, and induce cancer regression. However, an increase in endothelial [Ca²⁺]_i induced by aberrant ROS formation may result in endothelial dysfunction, inflammatory diseases, metabolic disorders, and pulmonary artery hypertension. This information could pave the way to design alternative treatments to interfere with the life-threatening interconnection between endothelial ROS and Ca²⁺ signaling under multiple pathological conditions.

EndMT Regulation by Small RNAs in Diabetes-Associated Fibrotic Conditions: Potential Link With Oxidative Stress

Diabetes-associated complications, such as retinopathy, nephropathy, cardiomyopathy, and atherosclerosis, the main consequences of long-term hyperglycemia, often lead to organ dysfunction, disability, and increased mortality. A common denominator of these complications is the myofibroblast-driven excessive deposition of extracellular matrix proteins. Although fibroblast appears to be the primary source of myofibroblasts, other cells, including endothelial cells, can generate myofibroblasts through a process known as endothelial to mesenchymal transition (EndMT). During EndMT, endothelial cells lose their typical phenotype to acquire mesenchymal features, characterized by the development of invasive and migratory abilities as well as the expression of typical mesenchymal products such as α-smooth muscle actin and type I collagen. EndMT is involved in many chronic and fibrotic diseases and appears to be regulated by complex molecular mechanisms and different signaling pathways. Recent evidence suggests that small RNAs, in particular microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), are crucial mediators of EndMT. Furthermore, EndMT and miRNAs are both affected by oxidative stress, another key player in the pathophysiology of diabetic fibrotic complications. In this review, we provide an overview of the primary redox signals underpinning the diabetic-associated fibrotic process. Then, we discuss the current knowledge on the role of small RNAs in the regulation of EndMT in diabetic retinopathy, nephropathy, cardiomyopathy, and atherosclerosis and highlight potential links between oxidative stress and the dyad small RNAs-EndMT in driving these pathological states.

Soluble guanylate cyclase chronic stimulation effects on cardiovascular reactivity in cafeteria diet-induced rat model of metabolic syndrome

Metabolic syndrome is linked to an increased risk of cardiovascular complications by a mechanism involving mainly decreased nitric oxide (NO) bioavailability and impaired NO-soluble guanylate cyclase (sGC)- cyclic guanosine monophosphate (cGMP) signalling (NO-sGC-cGMP). To further develop this scientific point, this study aimed to investigate the effects of long-term treatment with BAY 41-2272 (a sGC stimulator) on cardiovascular reactivity of spontaneously hypertensive rats (SHR) as a model of metabolic syndrome. SHR were randomly divided into 3 groups: control group, cafeteria diet (CD)-fed group and CD-fed group treated daily with BAY 41-2272 (5 mg/kg) by gastric gavage for 12 weeks. In vivo measurements of body weight, abdominal circumference, blood pressure and glucose tolerance test were performed. At the end of the feeding period, ex vivo cumulative concentration-response curves were performed on isolated perfused heart (isoproterenol (0.1 nM - 1 μM)) and thoracic aorta (phenylephrine (1 nM-10 μM), acetylcholine (1 nM-10 μM), and sodium nitroprusside (SNP) (0.1 nM-0.1 μM)). We showed that chronic CD feeding induced abdominal obesity, hypertriglyceridemia, glucose intolerance and exacerbated arterial hypertension in SHR. Compared to control group, CD-fed group showed a decrease in β-adrenoceptor-induced cardiac inotropy, in coronary perfusion pressure and in aortic contraction to phenylephrine. While relaxing effects of acetylcholine and SNP were unchanged. BAY 41-2272 long-term treatment markedly prevented arterial hypertension development and glucose intolerance, enhanced the α1-adrenoceptor-induced vasoconstriction, and restored cardiac inotropy and coronary vasodilation. These findings suggest that BAY 41-2272 may be a potential novel drug for preventing metabolic and cardiovascular complications of metabolic syndrome.

Endolysosomal Ca2+ signaling in cardiovascular health and disease

An increase in intracellular Ca²⁺ concentration ([Ca²⁺]_i) regulates a plethora of functions in the cardiovascular (CV) system, including contraction in cardiomyocytes and vascular smooth muscle cells (VSMCs), and angiogenesis in vascular endothelial cells and endothelial colony forming cells. The sarco/endoplasmic reticulum (SR/ER) represents the largest endogenous Ca²⁺ store, which releases Ca²⁺ through ryanodine receptors (RyRs) and/or inositol-1,4,5-trisphosphate receptors (InsP₃Rs) upon extracellular stimulation. The acidic vesicles of the endolysosomal (EL) compartment represent an additional endogenous Ca²⁺ store, which is targeted by several second messengers, including nicotinic acid adenine dinucleotide phosphate (NAADP) and phosphatidylinositol 3,5-bisphosphate [PI(3,5)P₂], and may release intraluminal Ca²⁺ through multiple Ca²⁺ permeable channels, including two-pore channels 1 and 2 (TPC1-2) and Transient Receptor Potential Mucolipin 1 (TRPML1). Herein, we discuss the emerging, pathophysiological role of EL Ca²⁺ signaling in the CV system. We describe the role of cardiac TPCs in β-adrenoceptor stimulation, arrhythmia, hypertrophy, and ischemia-reperfusion injury. We then illustrate the role of EL Ca²⁺ signaling in VSMCs, where TPCs promote vasoconstriction and contribute to pulmonary artery hypertension and atherosclerosis, whereas TRPML1 sustains vasodilation and is also involved in atherosclerosis. Subsequently, we describe the mechanisms whereby endothelial TPCs promote vasodilation, contribute to neurovascular coupling in the brain and stimulate angiogenesis and vasculogenesis. Finally, we discuss about the possibility to target TPCs, which are likely to mediate CV cell infection by the Severe Acute Respiratory Disease-Coronavirus-2, with Food and Drug Administration-approved drugs to alleviate the detrimental effects of Coronavirus Disease-19 on the CV system.

Bee Bread Ameliorates Vascular Inflammation and Impaired Vasorelaxation in Obesity-Induced Vascular Damage Rat Model: The Role of eNOS/NO/cGMP-Signaling Pathway

Obesity and hyperlipidemia are major risk factors for developing vascular diseases. Bee bread (BB) has been reported to exhibit some biological actions, including anti-obesity and anti-hyperlipidemic. This study aims to investigate whether bee bread can ameliorate vascular inflammation and impaired vasorelaxation activity through eNOS/NO/cGMP pathway in obese rats. Forty male Sprague-Dawley rats were randomly divided into four groups (n = 10/group), namely: control (normal group), obese rats (OB group), obese rats treated with bee bread (0.5 g/kg/day, OB/BB group) and obese rats treated with orlistat (10 mg/kg/day, OB/OR group). The latter three groups were given a high-fat diet (HFD) for 6 weeks to induced obesity before being administered with their respective treatments for another 6 weeks. After 12 weeks of the total experimental period, rats in the OB group demonstrated significantly higher Lee obesity index, lipid profile (total cholesterol, triglyceride, low-density lipoprotein), aortic proinflammatory markers (tumor necrosis factor-α, nuclear factor-κβ), aortic structural damage and impairment in vasorelaxation response to acetylcholine (ACh). Bee bread significantly ameliorated the obesity-induced vascular damage manifested by improvements in the lipid profile, aortic inflammatory markers, and the impaired vasorelaxation activity by significantly enhancing nitric oxide release, promoting endothelial nitric oxide synthase (eNOS) and cyclic guanosine monophosphate (cGMP) immunoexpression. These findings suggest that the administration of bee bread ameliorates the impaired vasorelaxation response to ACh by improving eNOS/NO/cGMP-signaling pathway in obese rats, suggesting its vascular therapeutic role.

Endothelial Dysfunction, Inflammation and Coronary Artery Disease: Potential Biomarkers and Promising Therapeutical Approaches

Coronary artery disease (CAD) and its complications are the leading cause of death worldwide. Inflammatory activation and dysfunction of the endothelium are key events in the development and pathophysiology of atherosclerosis and are associated with an elevated risk of cardiovascular events. There is great interest to further understand the pathophysiologic mechanisms underlying endothelial dysfunction and atherosclerosis progression, and to identify novel biomarkers and therapeutic strategies to prevent endothelial dysfunction, atherosclerosis and to reduce the risk of developing CAD and its complications. The use of liquid biopsies and new molecular biology techniques have allowed the identification of a growing list of molecular and cellular markers of endothelial dysfunction, which have provided insight on the molecular basis of atherosclerosis and are potential biomarkers and therapeutic targets for the prevention and or treatment of atherosclerosis and CAD. This review describes recent information on normal vascular endothelium function, as well as traditional and novel potential biomarkers of endothelial dysfunction and inflammation, and pharmacological and non-pharmacological therapeutic strategies aimed to protect the endothelium or reverse endothelial damage, as a preventive treatment for CAD and related complications.

From Metabolic Syndrome to Neurological Diseases: Role of Autophagy

Metabolic syndrome is not a single pathology, but a constellation of cardiovascular disease risk factors including: central and abdominal obesity, systemic hypertension, insulin resistance (or type 2 diabetes mellitus), and atherogenic dyslipidemia. The global incidence of Metabolic syndrome is estimated to be about one quarter of the world population; for this reason, it would be desirable to better understand the underlying mechanisms involved in order to develop treatments that can reduce or eliminate the damage caused. The effects of Metabolic syndrome are multiple and wide ranging; some of which have an impact on the central nervous system and cause neurological and neurodegenerative diseases. Autophagy is a catabolic intracellular process, essential for the recycling of cytoplasmic materials and for the degradation of damaged cellular organelle. Therefore, autophagy is primarily a cytoprotective mechanism; even if excessive cellular degradation can be detrimental. To date, it is known that systemic autophagic insufficiency is able to cause metabolic balance deterioration and facilitate the onset of metabolic syndrome. This review aims to highlight the current state of knowledge regarding the connection between metabolic syndrome and the onset of several neurological diseases related to it. Furthermore, since autophagy has been found to be of particular importance in metabolic disorders, the probable involvement of this degradative process is assumed to be responsible for the attenuation of neurological disorders resulting from metabolic syndrome.

Single-Cell Transcriptomic Atlas of Different Human Cardiac Arteries Identifies Cell Types Associated With Vascular Physiology

[Figure: see text].

Deletion of murine slc29a4 modifies vascular responses to adenosine and 5-hydroxytryptamine in a sexually dimorphic manner

Equilibrative nucleoside transporter 4 (ENT4), encoded by SLC29A4, mediates the flux of both 5‐hydroxytryptamine (5‐HT) and adenosine across cell membranes. We hypothesized that loss of ENT4 function in mice would modify the effects of these established regulators of vascular function. Male and female wild‐type (WT) and slc29a4‐null (ENT4‐KO) mice were compared with respect to their hemodynamics and mesenteric vascular function. Male ENT4‐KO mice had a complete loss of myogenic tone in their mesenteric resistance arteries. This was accompanied by a decrease in blood flow in the superior mesenteric artery in the male ENT4‐KO mice, and a reduced responsiveness to 5‐HT. In contrast, endothelium‐dependent relaxations of mesenteric arteries from female ENT4‐KO mice were more sensitive to Ca²⁺‐activated K⁺ (K_Ca) channel blockade than WT mice. Female ENT4‐KO mice also demonstrated an enhanced vasodilatory response to adenosine in vivo that was not seen in males. Ketanserin (5‐HT_2A inhibitor) and GR55562 (5‐HT_1B/1D inhibitor) decreased 5‐HT‐induced tone, but only ketanserin inhibited the relaxant effect of 5‐HT in mesenteric arteries. 5‐HT‐evoked increases in tone were elevated in arteries from ENT4‐KO mice upon block of endothelial relaxant pathways, with arteries from female ENT4‐KO mice showing the greatest increase. Adenosine A_2b receptor expression was decreased, while other adenosine transporter subtypes, as well as adenosine deaminase and adenosine kinase were increased in mesenteric arteries from male, but not female, ENT4‐KO mice. These findings indicate that deletion of slc29a4 leads to sex‐specific changes in vascular function with significant consequences for regulation of blood flow and pressure by adenosine and 5‐HT.

SIRT1-induced deacetylation of Akt expedites platelet phagocytosis and delays HEMEC aging

Maintaining the health of the endothelium is of critical importance to prevention against cell aging. The current study was performed to clarify the role of sirtuin1 (SIRT1) in platelet phagocytosis in cell aging and identified its downstream molecular mechanism. Platelet phagocytosis by human endometrial microvascular endothelial cells (HEMECs) was characterized by transmission electron and fluorescence microscopy. Functional experiments were conducted to examine platelet phagocytosis and cell aging using the overexpression or knockdown plasmids of SIRT1 and G alpha-interacting, vesicle-associated protein (GIRDIN) as well as Akt inhibitor and activator. It was found that SIRT1 facilitated platelet phagocytosis by HEMECs, contributing to inhibition of cell aging. Akt activation facilitated platelet phagocytosis and repressed cell aging. GIRDIN overexpression accelerated platelet phagocytosis by HEMECs, leading to a delay in cell aging. GIRDIN phosphorylation at Ser1417 was induced by Akt activation, while activation of Akt was induced by SIRT1-mediated deacetylation, consequently augmenting platelet phagocytosis and delaying cell aging. Taken together, SIRT1 delayed aging of HEMECs by deacetylating Akt, phosphorylating GIRDIN, and inducing platelet phagocytosis. The study highlights a possible target for the prevention of HEMEC aging.

The shifted balance of arginine metabolites in acute myocardial infarction patients and its clinical relevance

The arginine metabolism as a target for cardioprotection in patients with ST-segment elevation myocardial infarction (STEMI) remains insufficiently understood. Arginine, ornithine, citrulline, asymmetric dimethylarginine (ADMA) and proline plasma levels were measured using liquid chromatography and tandem mass spectrometry in 70 consecutive STEMI patients upon admission and at 6-month follow-up and were compared with left ventricular function, volumes, and infarct characteristics determined by cardiac magnetic resonance imaging, and with 5-year clinical outcomes. Baseline median concentration of arginine was higher by 49% (P = 0.002) when compared to 6-month measurements and was correlated with an ischemia risk area (R = 0.34, P = 0.004) and infarct size (R = 0.33, P = 0.006). Following ischemia median citrulline/arginine index decreased when compared with 6-month result (P = 0.002), while citrulline/ornithine and arginine/ADMA ratios maintained unchanged indicating a shift of arginine metabolism from nitric oxide synthase (NOS) towards arginase. The 6-month arginine concentration reached the area under the ROC curve of 0.67 (95% confidence interval 0.54–0.81) for prediction of death, myocardial infarction or heart failure hospitalization and its value of < 29 µM was associated with lower event free survival (P = 0.02). In STEMI patients, during ischemia conversion of elevated plasma arginine was shifted from NOS towards arginase. Decreased 6-month arginine concentrations were associated with worse long-term outcomes.

The Cardiovascular Therapeutic Potential of Propolis-A Comprehensive Review

Simple Summary

Propolis, also described as bee glue, is a natural component made up of a resinous mixture of honeybee compounds from multiple botanical sources. The literature has demonstrated a variety of medicinal properties attributed to propolis due to its chemical complexity. However, the positive effects of propolis on cardiovascular health have gained little coverage. Therefore, we aimed to provide an accurate and up-to-date review of the main cardiovascular health benefits of propolis. In particular, we intend to establish the key varieties of propolis and pharmacological compounds with the therapeutic effects that are most encouraging, as well as the physiological processes by which those advantages are accomplished. The Brazilian green and red varieties reveal the greatest number of beneficial activities among the varieties of propolis studied. While much of the cardiovascular beneficial effects appear to derive from the cumulative actions of several compounds working via multiple signaling mechanisms, some individual compounds that may enhance the existing therapeutic arsenal have also shown significant results. It is also worth exploring the prospect of using propolis as food supplements.

Abstract

Owing to its chemical richness, propolis has a myriad of therapeutic properties. To the authors’ knowledge, this is the first comprehensive review paper on propolis to focus exclusively on its major effects for cardiovascular health. The propolis compound varieties with the most promising therapeutic benefits and their respective physiological mechanisms will be discussed. Propolis displays an anti-atherosclerotic activity, attained through modulation of the plasma lipid profile and through stabilization of the fatty plaque by inhibiting macrophage apoptosis, vascular smooth muscle proliferation and metalloproteinase activity. The antihypertensive effects of propolis probably arise through the combination of several mechanisms, including the suppression of catecholamine synthesis, stimulation of endothelium-dependent vasorelaxation and vascular anti-inflammatory activity. The anti-hemostatic activity of propolis is attributed to the inhibition of platelet plug formation and antifibrinolytic activity. By inhibiting the secretion of proangiogenic factors, propolis suppresses endothelial cell migration and tubulogenesis, exerting antiangiogenic activity. The antioxidant and anti-inflammatory activities are responsible for protection against vascular endothelial and cardiomyocyte dysfunction, mostly by the prevention of oxidative stress. Among the reviewed propolis varieties, the Brazilian green and red varieties show the largest number of beneficial activities. Further research, especially preclinical, should be conducted to assess the cardiovascular benefits of the given varieties with different compositions.

KCa channel activation normalizes endothelial function in Type 2 Diabetic resistance arteries by improving intracellular Ca2+ mobilization

BACKGROUND

Endothelial dysfunction is an early pathogenic event in the progression of cardiovascular disease in patients with Type 2 Diabetes (T2D). Endothelial KCa2.3 and KCa3.1 K⁺ channels are important regulators of arterial diameter, and we thus hypothesized that SKA-31, a small molecule activator of KCa2.3 and KCa3.1, would positively influence agonist-evoked dilation in myogenically active resistance arteries in T2D.

METHODOLOGY

Arterial pressure myography was utilized to investigate endothelium-dependent vasodilation in isolated cremaster skeletal muscle resistance arteries from 22 to 24 week old T2D Goto-Kakizaki rats, age-matched Wistar controls, and small human intra-thoracic resistance arteries from T2D subjects. Agonist stimulated changes in cytosolic free Ca²⁺ in acutely isolated, single endothelial cells from Wistar and T2D Goto-Kakizaki cremaster and cerebral arteries were examined using Fura-2 fluorescence imaging.

MAIN FINDINGS

Endothelium-dependent vasodilation in response to acetylcholine (ACh) or bradykinin (BK) was significantly impaired in isolated cremaster arteries from T2D Goto-Kakizaki rats compared with Wistar controls, and similar results were observed in human intra-thoracic arteries. In contrast, inhibition of myogenic tone by sodium nitroprusside, a direct smooth muscle relaxant, was unaltered in both rat and human T2D arteries. Treatment with a threshold concentration of SKA-31 (0.3 μM) significantly enhanced vasodilatory responses to ACh and BK in arteries from T2D Goto-Kakizaki rats and human subjects, whereas only modest effects were observed in non-diabetic arteries of both species. Mechanistically, SKA-31 enhancement of evoked dilation was independent of vascular NO synthase and COX activities. Remarkably, SKA-31 treatment improved agonist-stimulated Ca²⁺ elevation in acutely isolated endothelial cells from T2D Goto-Kakizaki cremaster and cerebral arteries, but not from Wistar control vessels. In contrast, SKA-31 treatment did not affect intracellular Ca²⁺ release by the sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA) inhibitor cyclopiazonic acid.

CONCLUSIONS

Collectively, our data demonstrate that KCa channel modulation can acutely restore endothelium-dependent vasodilatory responses in T2D resistance arteries from rats and humans, which appears to involve improved endothelial Ca²⁺ mobilization.

Cardiovascular Disease in Spondyloarthritides

The spondyloarthritides are a group of chronic systemic inflammatory joint diseases, the main types being ankylosing spondylitis (AS) and psoriatic arthritis (PsA). Evidence accumulating during the last decades suggests that patients with AS or PsA carry an increased risk for cardiovascular disease and cardiovascular death. This risk appears to be mediated by systemic inflammation over and above classical cardiovascular risk factors. The excess cardiovascular risk in those patients has been formally acknowledged by scientific organizations, which have called physicians' attention to the matter. The application by Rheumatologists of new effective anti-rheumatic treatments and treat-to-target strategies seems to benefit patients from a cardiovascular point of view, as well. However, more data are needed in order to verify whether anti-rheumatic treatments do have an effect on cardiovascular risk and whether there are differences among them in this regard. Most importantly, a higher level of awareness of the cardiovascular risk is needed among patients and healthcare providers, better tools to recognize at-risk patients and, ultimately, commitment to address in parallel both the musculoskeletal and the cardiovascular aspect of the disease.

Cutaneous microcirculation in patients with peripheral arterial occlusive disease: Comparison of capillary blood circulation in the nail fold of finger and toe

In patients with peripheral arterial occlusive disease (PAOD) a restricted circulation in cutaneous microvessels has been reported. In this study the velocity of erythrocytes (very) in finger nailfold capillaries - a vascular area without upstream macroangiopathy - and also in toe nailfold capillaries - a post-stenotic area –was investigated using capillary microscopy in apparently healthy subjects and patients with PAOD. Already in finger nailfold capillaries very of patients with PAOD under resting conditions was significantly lower than in capillaries of healthy subjects. This was also true for the circulation in toe capillaries. In addition, the erythrocyte velocities under resting conditions in the toe capillaries were significantly lower than in the finger capillaries. Similar results were found for the duration and the maximum velocity of postocclusive hyperemia. It is concluded that the resting blood flow in the skin microcirculation is impaired in PAOD patients, both under resting conditions and during postocclusive hyperemia in finger as well in toe nailfold capillaries.