Endothelial function and dysfunction: testing and clinical relevance

A Novel Function of NaV Channel β3 Subunit in Endothelial Cell Alignment Through Autophagy Modulation

Endothelial cells (EC) play a pivotal role in vascular homeostasis. By sensing shear stress generated by blood flow, EC endorse vasculoprotection through mechanotransduction signaling pathways. Various ion channels are involved in mechanosignaling, and here, we investigated the endothelial voltage-gated Na+ channels (NaV channels), since their mechanosensitivity has been previously demonstrated in cardiomyocytes. First, we showed that EC from aorta (TeloHAEC) behave as EC from umbilical vein (HUVEC) under laminar shear stress (LSS). For both EC models, cell alignment and elongation occurred with the activation of the KLF2/KLF4 atheroprotective signaling pathways. We found that LSS decreased the expression of SCN5A, encoding NaV1.5, while LSS increased that of SCN3B, encoding NaVβ3. We demonstrated that the KLF4 transcription factor is involved in SCN3B expression under both static and LSS conditions. Interestingly, SCN3B silencing impaired EC alignment induced by LSS. The characterization of NaVβ3 interactome by coimmunoprecipitation and proteomic analysis revealed that mTOR, implicated in autophagy, binds to NaVβ3. This result was evidenced by the colocalization between NaVβ3 and mTOR inside cells. Moreover, we showed that SCN3B silencing led to the decrease in LC3B expression and the number of LC3B positive autophagosomes. Furthermore, we showed that NaVβ3 is retained within the cell and colocalized with LAMP1 and LC3B. Finally, we found that resveratrol, a stimulating-autophagy and vasculoprotective molecule, induced KLF4 together with NaVβ3 expression. Altogether, our findings highlight a novel role of NaVβ3 in endothelial function and cell alignment as an actor in shear stress vasculoprotective intracellular pathway through autophagy modulation.

Lung endothelial cell heterogeneity in health and pulmonary vascular disease

Lung endothelial cells (ECs) are essential for maintaining organ function and homeostasis. Despite sharing some common features with ECs from organ systems, lung ECs exhibit significant heterogeneity in morphology, function, and gene expression. This heterogeneity is increasingly recognized as a key contributor to the development of pulmonary diseases like pulmonary hypertension (PH). In this mini-review, we explore the evolving understanding of lung EC heterogeneity, particularly through the lens of single-cell RNA sequencing (scRNA-seq) technologies. These advances have provided unprecedented insights into the diverse EC subpopulations, their specific roles, and the disturbances in their homeostatic functions that contribute to PH pathogenesis. In particular, these studies identified novel and functionally distinct cell types such as aerocytes and general capillary ECs that are critical for maintaining lung function in health and disease. In addition, multiple novel pathways and mechanisms have been identified that contribute to aberrant pulmonary vascular remodeling in PH. Emerging techniques like single-nucleus RNA sequencing and spatial transcriptomics have further pushed the field forward by discovering novel disease mediators. As research continues to leverage these advanced techniques, the field is poised to uncover novel EC subtypes and disease mechanisms, paving the way for new therapeutic targets in PH and other lung diseases.

Endothelial Krüppel-like factor 2/4: Regulation and function in cardiovascular diseases

This review presents an overview of the regulation, function, disease-relevance and pharmacological regulation of the critical endothelial transcription factors KLF2/4 in vasculature. The regulatory mechanisms of KLF2/4 expression and activity in vascular endothelium in response to hemodynamic forces and biochemical stimuli are depicted. The functional effects mediated by direct or indirect target genes of KLF2/4 in endothelial cells are systematically summarized. The contributory roles that dysregulated KLF2/4 play in relevant cardiovascular pathologies, such as atherosclerotic vascular lesions, pulmonary arterial hypertension and vascular complications of diabetes were reviewed. Moreover, this review also discusses the pharmacological regulation of KLF2/4 by drugs used in clinics and therapeutic possibility by directly targeting these two transcription factors for treating atherosclerotic cardiovascular diseases. Finally, prospective opinions on the gaps in disclosing novel vascular function mediated by KLF2/4 and future research needs are expressed.

Sex-Specific Antioxidant and Anti-Inflammatory Protective Effects of AMPK in Cardiovascular Diseases

Cardiovascular diseases such as coronary heart disease, heart failure, or stroke are the most common cause of death worldwide and are regularly based on risk factors like diabetes mellitus, hypertension, or obesity. At the same time, both diseases and risk factors are significantly influenced by sex hormones. In order to better understand this influence and also specifically improve the therapy of female patients, medical research has recently focused increasingly on gender-specific differences. The goal is to develop personalized, gender-specific therapy concepts for these diseases to further enhance health outcomes. The enzyme adenosine monophosphate-activated protein kinase (AMPK) is a central regulator of energy metabolism, protecting the cardiovascular system from energy depletion, thereby promoting vascular health and preventing cellular damage. AMPK confers cardioprotective effects by preventing endothelial and vascular dysfunction, and by controlling or regulating oxidative stress and inflammatory processes. For AMPK, sex-specific effects were reported, influencing metabolic and cardiovascular responses. Exercise and metabolic stress generally cause higher AMPK activity in males. At the same time, females exhibit protective mechanisms against insulin resistance or oxidative stress, particularly in conditions like obesity. Additionally, males subject to AMPK deficiency seem to experience greater cardiac and mitochondrial dysfunction. In contrast, females show improvement in cardiovascular function after pharmacological AMPK activation. These differences, influenced by hormones, body composition, and gene expression, highlight the potential to develop personalized, sex-specific AMPK-targeted therapeutic strategies for cardiovascular diseases in the future. Here, we discuss the most actual scientific background, focusing on the protective, gender-specific effects of AMPK, and highlight potential clinical applications.

Strategies for improved endothelial cell adhesion in microphysiological vascular model systems

Human tissue-engineered blood vessels (TEBVs) have been applied as model systems to study a wide range of vascular diseases including Hutchinson-Gilford Progeria Syndrome and early atherosclerosis. Central to the utility of TEBVs as an in vitro blood vessel model is the maintenance of a functional endothelium under physiologically relevant shear stresses. Establishing and maintaining a confluent endothelial monolayer is challenging. In this protocol, we outline an optimized procedure for the endothelialization of TEBVs. We optimized the following key conditions affecting endothelial cell (EC) adherence in the vessel: EC seeding density, rotation time, and the application of perfusion. This protocol results in TEBVs with sustained EC luminal coverage that demonstrate alignment in the direction of applied flow and responsiveness to inflammatory stimuli. To facilitate rapid screening of EC coverage during the fabrication and perfusion steps, we re-designed TEBV chambers to include a viewing window that allows for efficient monitoring and assessment of the endothelialization process using fluorescence microscopy. By identifying key factors that affect EC attachment in TEBVs, this protocol may serve as a valuable resource for researchers seeking to achieve successful endothelialization of engineered blood vessel constructs.

Effects of SGLT2 inhibitors on ion channels in heart failure: focus on the endothelium

Heart failure (HF) is a life-threatening cardiovascular disease associated with high mortality, diminished quality of life, and a significant economic burden on both patients and society. The pathogenesis of HF is closely related to the endothelium, where endothelial ion channels play an important role in regulating intracellular Ca2+ signals. These ion channels are essential to maintain vascular function, including endothelium-dependent vascular tone, inflammation response, and oxidative stress. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have shown promising cardiovascular benefits in HF patients, reducing mortality risk and hospitalization in several large clinical trials. Clinical and preclinical studies indicate that the cardioprotective effects of SGLT2i in HF are mediated by endothelial nitric oxide (NO) pathways, as well as by reducing inflammation and reactive oxygen species in cardiac endothelial cells. Additionally, SGLT2i may confer endothelial protection by lowering intracellular Ca2+ level through the inhibition of sodium-hydrogen exchanger 1 (NHE1) and sodium-calcium exchanger (NCX) in endothelial cells. In this review, we discuss present knowledge regarding the expression and role of Ca2+-related ion channels in endothelial cells in HF, focusing on the effects of SGLT2i on endothelial NHE1, NCX as well as on vascular tone.

20 nm nanoparticles trigger calcium influx to endothelial cells via a TRPV4 channel

While increased intracellular calcium (Ca2+) has been identified as a key effect of nanoparticles on endothelial cells, the mechanism has not been fully elucidated or examined under shear stress. Here, we show the effect of several types of 20 nm particles on Ca2+ in the presence of shear stress in human umbilical vein endothelial cells (HUVECs), human coronary artery endothelial cells (HCAECs), and human cardiac microvascular endothelial cells (HMVEC-Cs). Intracellular Ca2+ levels increased by nearly three-fold in these cell types upon exposure to 100 μg mL-1 20 nm Au particles, which was not seen in response to larger or smaller particles. An antagonist to the calcium channel - transient receptor potential vanilloid-type 4 (TRPV4) - drastically reduced the amount of calcium by 9.3-fold in HUVECs exposed to 0.6 Pa shear stress and 100 μg mL-1 20 nm gold particles, a trend upheld in both HCAECs and HMVEC-Cs. Cell alignment in the direction of fluid flow is a well-known phenomenon in endothelial cells, and interestingly, cells in the presence of 20 nm particles with fluid flow had a higher alignment index than cells in the fluid flow alone. When compared with previous works, these results indicated that 20 nm particles may be inducing endothelial permeability by activating the TRPV4 channel in vitro. The potential of nanoparticle delivery technologies hinges on an improved understanding of this effect toward improved delivery with limited toxicity.

Effects of high-intensity interval training vs. moderate-intensity continuous training on arterial stiffness in adults: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Arterial stiffness (AS) is regarded as an independent predictor of cardiovascular events and all-cause mortality, and it is significantly associated with global mortality rates. Physical activity (PA) plays a positive role in reducing AS and improving cardiovascular health. The aim of this study is to compare the differences between high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) in their effects on reducing AS.

METHODS

We conducted a comprehensive search of the PubMed, Cochrane, Embase, Web of Science, and EBSCO electronic databases, covering the period from their inception to January 10, 2025. We used a fixed-effect model to compare the changes in pulse wave velocity (PWV) before and after intervention between the HIIT group and the MICT group. Data were reported using the weighted mean difference (WMD) and 95 % confidence interval (95 % CI).

RESULTS

This study included 619 participants from 22 studies. Compared to MICT, HIIT demonstrated a more significant reduction in PWV (-0.10 m/s [95 % CI:0.16 to -0.03], P = 0.005). Additionally, we found that HIIT was superior in reducing CF-PWV (-0.10 m/s [95 % CI:0.17 to -0.02], P = 0.01).

CONCLUSION

HIIT is more effective than MICT in improving PWV and promoting arterial health in adults.

Silencing KRIT1 Partially Reverses the Effects of Disturbed Flow on the Endothelial Cell Transcriptome

Endothelial cells respond to forces generated by laminar blood flow with changes in vasodilation, anticoagulant, fibrinolytic, or anti-inflammatory functions which preserve vessel patency. These responses to flow shear stress are primarily mediated by the modulation of the following transcription factors: Krüppel-like factors 2 and 4 (KLF2 and KLF4). Notably, disturbed flow patterns, which are found in vascular areas predisposed to atherosclerosis, significantly reduce the endothelial expression of KLF2 and KLF4, resulting in changes in the transcriptome that exacerbate inflammation and thrombosis. The endothelial CCM (Cerebral Cavernous Malformation) complex, comprising KRIT1 (Krev1 interaction trapped gene 1), CCM2 (Malcavernin), and CCM3 (Programmed cell death protein 10), suppresses the expression of KLF2 and KLF4. Loss of function of the CCM complex has recently been suggested to protect from coronary atherosclerosis in humans. We thus hypothesized that the silencing of KRIT1, the central scaffold of the CCM complex, can normalize the atherogenic effects of disturbed flow on the human endothelial transcriptome. Bulk RNA sequencing (RNA-seq) was conducted on human umbilical vein endothelial cells (HUVECs) after the expression of KRIT1 was silenced using specific small interfering RNA (siRNA). The endothelial cells were exposed to three different conditions for 24 h, as follows: pulsatile shear stress (laminar flow), oscillatory shear stress (disturbed flow), and static conditions (no flow). We found that silencing the KRIT1 expression in HUVECs restored the expression of the transcription factors KLF2 and KLF4 under oscillatory shear stress. This treatment resulted in a transcriptomic profile similar to that of endothelial cells under pulsatile shear stress. These findings suggest that inhibition of the CCM complex in endothelium plays a vasoprotective role by reactivating a protective gene program to help endothelial cells resist disturbed blood flow. Targeting CCM genes can activate well-known vasoprotective gene programs that enhance endothelial resilience to inflammation, hypoxia, and angiogenesis under disturbed flow conditions, providing a novel pathway for preventing atherothrombosis.

Cyclic nucleotide phosphodiesterases as drug targets

Cyclic nucleotides are synthesized by adenylyl and/or guanylyl cyclase, and downstream of this synthesis, the cyclic nucleotide phosphodiesterase families (PDEs) specifically hydrolyze cyclic nucleotides. PDEs control cyclic adenosine-3',5'monophosphate (cAMP) and cyclic guanosine-3',5'-monophosphate (cGMP) intracellular levels by mediating their quick return to the basal steady state levels. This often takes place in subcellular nanodomains. Thus, PDEs govern short-term protein phosphorylation, long-term protein expression, and even epigenetic mechanisms by modulating cyclic nucleotide levels. Consequently, their involvement in both health and disease is extensively investigated. PDE inhibition has emerged as a promising clinical intervention method, with ongoing developments aiming to enhance its efficacy and applicability. In this comprehensive review, we extensively look into the intricate landscape of PDEs biochemistry, exploring their diverse roles in various tissues. Furthermore, we outline the underlying mechanisms of PDEs in different pathophysiological conditions. Additionally, we review the application of PDE inhibition in related diseases, shedding light on current advancements and future prospects for clinical intervention. SIGNIFICANCE STATEMENT: Regulating PDEs is a critical checkpoint for numerous (patho)physiological conditions. However, despite the development of several PDE inhibitors aimed at controlling overactivated PDEs, their applicability in clinical settings poses challenges. In this context, our focus is on pharmacodynamics and the structure activity of PDEs, aiming to illustrate how selectivity and efficacy can be optimized. Additionally, this review points to current preclinical and clinical evidence that depicts various optimization efforts and indications.

Reshaping the chromatin landscape in HUVECs from small-for-gestational-age newborns

Small for gestational age (SGA), with increased risk of adult-onset cardiovascular diseases and metabolic syndromes, is known to associate with endothelial dysfunction, but the pathogenic mechanisms remain unclear. In this study, the pathological state of human umbilical vein endothelial cells (HUVECs) from SGA individuals was characterized by presenting increased angiogenesis, migration, proliferation, and wound healing ability relative to their normal counterparts. Genome-wide mapping of transcriptomes and open chromatins unveiled global gene expression alterations and chromatin remodeling in SGA-HUVECs. Specifically, we revealed increased chromatin accessibility at active enhancers, along with dysregulation of genes associated with angiogenesis, and further identified CD44 as the key gene driving HUVECs' dysfunction by regulating pro-angiogenic genes' expression and activating phosphorylated ERK1/2 and phosphorylated endothelial NOS expression in SGA. In SGA-HUVECs, CD44 was abnormally upregulated by 3 active enhancers that displayed increased chromatin accessibility and interacted with CD44 promoter. Subsequent motif analysis uncovered activating protein-1 (AP-1) as a crucial transcription factor regulating CD44 expression by binding to CD44 promoter and associated enhancers. Enhancers CRISPR interference and AP-1 inhibition restored CD44 expression and alleviated the hyperangiogenesis of SGA-HUVECs. Together, our study provides a foundational understanding of the epigenetic alterations driving pathological angiogenesis and offers potential therapeutic insights into addressing endothelial dysfunction in SGA.

Endothelial dysfunction in cardiovascular diseases: mechanisms and in vitro models

Endothelial cells (ECs) are arranged side-by-side to create a semi-permeable monolayer, forming the inner lining of every blood vessel (micro and macrocirculation). Serving as the first barrier for circulating molecules and cells, ECs represent the main regulators of vascular homeostasis being able to respond to environmental changes, either physical or chemical signals, by producing several factors that regulate vascular tone and cellular adhesion. Healthy endothelium has anticoagulant properties that prevent the adhesion of leukocytes and platelets to the vessel walls, contributing to resistance to thrombus formation, and regulating inflammation, and vascular smooth muscle cell proliferation. Many risk factors of cardiovascular diseases (CVDs) promote the endothelial expression of chemokines, cytokines, and adhesion molecules. The resultant endothelial activation can lead to endothelial cell dysfunction (ECD). In vitro models of ECD allow the study of cellular and molecular mechanisms of disease and provide a research platform for screening potential therapeutic agents. Even though alternative models are available, such as animal models or ex vivo models, in vitro models offer higher experimental flexibility and reproducibility, making them a valuable tool for the understanding of pathophysiological mechanisms of several diseases, such as CVDs. Therefore, this review aims to synthesize the currently available in vitro models regarding ECD, emphasizing CVDs. This work will focus on 2D cell culture models (endothelial cell lines and primary ECs), 3D cell culture systems (scaffold-free and scaffold-based), and 3D cell culture models (such as organ-on-a-chip). We will dissect the role of external stimuli-chemical and mechanical-in triggering ECD.

The interplay between endothelial glycocalyx maturity and both the toxicity and intracellular uptake of charged nanoparticles

Nanoparticles are widely studied for delivering treatments to target tissues, but few have reached clinical use. Most nanoparticles encounter blood vessels on their way to target tissues. The inner surface of these vessels is lined with endothelial cells covered by a glycocalyx, an extracellular matrix rich in anionic glycans. The role of the glycocalyx in nanoparticle interactions is not well understood. Here, we demonstrate that endothelial cells need extended culture times to synthesize a mature glycocalyx. Our research shows that branched polyethyleneimine functionalized gold nanoparticles bind to endothelial cells expressing either a developing or mature glycocalyx, with the interaction involving hyaluronan and heparan sulfate. These nanoparticles are subsequently internalized. Similar results were seen with poly(L-arginine). A mature glycocalyx protects cells by reducing the toxicity of these cationic nanoparticles. In contrast, lipoic acid-functionalized gold nanoparticles are internalized by cells with a developing glycocalyx, but not a mature one. Poly(L-glutamic acid) only interacts with cells when major glycans in the glycocalyx are degraded. These findings highlight the complex relationship between nanoparticle charge and structure, and their effects on toxicity, binding, and uptake by endothelial cells. This offers important insights for improving nanoparticle interactions with blood vessels in health and disease. STATEMENT OF SIGNIFICANCE: Endothelial cells lining blood vessels form a barrier through which nanoparticles must cross to reach target tissues. These cells are covered with a layer called the glycocalyx, which is rich in anionic glycans. However, the role of the glycocalyx in how nanoparticles interact with cells remains underexplored. Our research revealed that cells with a mature glycocalyx internalize cationic nanoparticles and experience reduced cytotoxicity. Conversely, a mature glycocalyx prevents anionic nanoparticles from entering cells. These results suggest that the structure of both the nanoparticles and the glycocalyx should be considered in future studies to improve the use of nanoparticles for medical applications.

The mechanisms and applications of endothelial progenitor cell therapy in the treatment of intracranial aneurysm

The pathophysiological mechanism of intracranial aneurysm (IA) involves the dynamic interaction of ECM abnormalities, hemodynamic stress, and inflammatory response. The rupture of intracranial aneurysm will cause serious consequences. Multiple studies have confirmed the important role and potential application of endothelial progenitor cells (EPCs) in vascular repair. This review focuses on the specific mechanism of EPCs in the treatment of intracranial aneurysms, which promote re-endothelialization and angiogenesis through bone marrow mobilization, targeted migration to the site of injury, differentiation into mature endothelial cells, and secretion of angiogenic factors. In addition, EPCs maintain ECM homeostasis by regulating MMP/IMP balance, inhibiting aneurysm wall thinning and structural damage. Based on the vascular repair mechanism of EPCs, new treatment strategies such as "biologically active" spring coils (loaded with EPCs or SDF-1α) and flow diverters(FDs) combined with EPCs therapy have been developed to synergistically promote carotid endothelialization of aneurysms and reduce the risk of recurrence. Future research needs to further validate the long-term efficacy and precise regulatory mechanisms of EPCs in clinical translation, providing new directions for IA treatment.

Treatment of endothelial cell dysfunction in atherosclerosis: a new perspective integrating traditional and modern approaches

Atherosclerosis (AS), a prime causative factor in cardiovascular disease, originates from endothelial cell dysfunction (ECD). Comprising a vital part of the vascular endothelium, endothelial cells play a crucial role in maintaining vascular homeostasis, optimizing redox balance, and regulating inflammatory responses. More evidence shows that ECD not only serves as an early harbinger of AS but also exhibits a strong association with disease progression. In recent years, the treatment strategies for ECD have been continuously evolving, encompassing interventions ranging from lifestyle modifications to traditional pharmacotherapy aimed at reducing risk factors, which also have demonstrated the ability to improve endothelial cell function. Additionally, novel strategies such as promising biotherapy and gene therapy have drawn attention. These methods have demonstrated enormous potential and promising prospects in improving endothelial function and reversing AS. However, it is essential to remain cognizant that the current treatments still present significant challenges regarding therapeutic efficacy, long-term safety, and ethical issues. This article aims to provide a systematic review of these treatment methods, analyze the mechanisms and efficacy of various therapeutic strategies, with the goal of offering insights and guidance for clinical practice, and further advancing the prevention and treatment of cardiovascular diseases.

Genetic or therapeutic disruption of the Reelin/Apoer2 signaling pathway improves inflammatory arthritis outcomes

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial inflammation, pannus formation, and progressive joint destruction. The inflammatory milieu in RA drives endothelial cell activation and upregulation of adhesion molecules, thus facilitating leukocyte infiltration into the synovium. Reelin, a circulating glycoprotein previously implicated in endothelial activation and leukocyte recruitment in diseases such as atherosclerosis and multiple sclerosis, has emerged as a potential upstream regulator of these processes. However, its role in RA pathogenesis remains poorly understood. Here, we demonstrate that Reelin levels are markedly elevated in the plasma of both RA patients and mouse models of arthritis, with higher concentrations correlating with greater disease severity. Genetic deletion of the Reelin receptor Apoer2 conferred significant protection against serum transfer arthritis (STA), underscoring the relevance of this pathway in disease progression. Furthermore, therapeutic inhibition of Reelin using the CR-50 antibody yielded robust anti-inflammatory effects in multiple preclinical arthritis models, including STA, K/BxN, and collagen-induced arthritis. Notably, CR-50 treatment not only reduced leukocyte infiltration and synovial inflammation but also mitigated pannus formation. Importantly, these benefits were achieved without the gastrointestinal side effects commonly associated with nonsteroidal anti-inflammatory drugs like diclofenac. Our findings position Reelin as a proinflammatory endothelial biomarker and therapeutic target in RA. By modulating endothelial activation and leukocyte recruitment, anti-Reelin strategies offer an alternative approach to attenuate synovial inflammation and joint damage. These results provide a compelling rationale for further exploration of Reelin-targeted therapies as alternatives to conventional immunosuppressive treatments in RA and other chronic inflammatory diseases.

Silencing KRIT1 Partially Reverses the Effects of Disturbed Flow on the Endothelial Cell Transcriptome

Background

Endothelial cells respond to forces generated by laminar blood flow with changes in vasodilation, anticoagulant, fibrinolytic, or anti-inflammatory functions which preserve vessel patency. These responses to flow sheer stress are primarily mediated by the modulation of transcription factors Krüppel-like factors 2 and 4 (KLF2 and KLF4). Notably, disturbed flow patterns, which are found in vascular areas predisposed to atherosclerosis, significantly reduce the endothelial expression of KLF2 and KLF4, resulting in changes in the transcriptome that exacerbate inflammation and thrombosis. The endothelial CCM complex, comprising KRIT1, CCM2, and CCM3, suppresses the expression of KLF2 and KLF4. Loss of function of the CCM complex has recently been suggested to protect from coronary atherosclerosis in humans. We thus hypothesized that silencing of KRIT1, the central scaffold of the CCM complex, can normalize the atherogenic effects of disturbed flow on the human endothelial transcriptome.

Methods

Bulk RNA sequencing (RNA-seq) was conducted on human umbilical vein endothelial cells (HUVECs) after the expression of KRIT1 was silenced using specific siRNAs. The endothelial cells were exposed to three different conditions for 24 hours: pulsatile shear stress (laminar flow), oscillatory shear stress (disturbed flow), and static conditions (no flow).

Results

We found that silencing KRIT1 expression in HUVECs restored the expression of the transcription factors KLF2 and KLF4 under oscillatory shear stress. This treatment resulted in a transcriptomic profile similar to that of endothelial cells under pulsatile shear stress. These findings suggest that inhibition of the CCM complex in endothelium plays a vasoprotective role by reactivating a protective gene program to help endothelial cells resist disturbed blood flow.

Conclusions

Targeting CCM genes can activate well-known vasoprotective gene programs that enhance endothelial resilience to inflammation, hypoxia, and angiogenesis under disturbed flow conditions, providing a novel pathway for preventing atherosclerosis.

Computational Design and In Vitro and In Vivo Characterization of an ApoE-Based Synthetic High-Density Lipoprotein for Sepsis Therapy

Introduction: Septic patients have low levels of high-density lipoproteins (HDLs), which is a risk factor. Replenishing HDLs with synthetic HDLs (sHDLs) has shown promise as a therapy for sepsis. This study aimed to develop a computational approach to design and test new types of sHDLs for sepsis treatment. Methods: We used a three-step computational approach to design sHDL nanoparticles based on the structure of HDLs and their binding to endotoxins. We tested the efficacy of these sHDLs in two sepsis mouse models-cecal ligation and puncture (CLP)-induced and P. aeruginosa-induced sepsis models-and assessed their impact on inflammatory signaling in cells. Results: We designed four sHDL nanoparticles: two based on the ApoA-I sequence (YGZL1 and YGZL2) and two based on the ApoE sequence (YGZL3 and YGZL4). We demonstrated that an ApoE-based sHDL nanoparticle, YGZL3, provides effective protection against CLP- and P. aeruginosa-induced sepsis. The sHDLs effectively suppressed inflammatory signaling in HEK-blue or RAW264 cells. Conclusions: Unlike earlier approaches, we developed a new approach that employs computational simulations to design a new type of sHDL based on HDL's structure and function. We found that YGZL3, an ApoE sequence-based sHDL, provides effective protection against sepsis in two mouse models.

Improvement of Microvascular Function in Patients with Morbid Obesity After Bariatric Surgery Revealed by Imaging Photoplethysmography

BACKGROUND

Morbid obesity leads to serious complications such as diabetes mellitus, arterial hypertension, and atherosclerosis. Bariatric surgery aims to reduce body weight and correct metabolic disorders and associated macro- and microvascular dysfunction. Metabolic disturbances can be assessed by biochemical markers, whereas microvascular function can be assessed by the response to provocative stimuli. The aim of this work is to quantitatively assess the cutaneous microcirculatory change caused by bariatric surgery using imaging photoplethysmography.

METHODS

The study included 20 patients with obesity whose body mass index (BMI) was greater than 40 kg/m2 who underwent bariatric surgery and 20 control subjects. Microvascular function was assessed twice, before and 6 months after surgery, by measuring the perfusion response to local forearm heating up to 40 °C using imaging photoplethysmography.

RESULTS

The perfusion response to local heating was found to be significantly lower in patients with obesity before surgery compared to the control group, but 6 months after surgery, it approaches indicators of the control group, along with a decrease in BMI from 48 ± 5 to 36 ± 5 kg/m2, P < 0.001. Besides, bariatric surgery improves biochemical markers of metabolic syndrome (glycated hemoglobin decreases from 6.3 ± 1.0 to 5.2 ± 0.4% and cholesterol from 5.2 ± 1.4 to 4.2 ± 0.8 mmol/l).

CONCLUSION

Based on these results, we conclude that microvascular abnormalities caused by obesity could be repaired after bariatric surgery and subsequent conservative treatment.

Impact of Quantity and Type of Dietary Protein on Cardiovascular Disease Risk Factors Using Standard and Network Meta-analyses of Randomized Controlled Trials

CONTEXT

Higher protein diets (HPDs) have shown favorable outcomes on weight maintenance and body-composition management; however, their protective effects against cardiovascular diseases (CVDs) remain uncertain and contentious. Furthermore, it is important to consider the influence of other macronutrients in the diet and type of dietary protein when studying HPDs, because this aspect has been overlooked in previous studies.

OBJECTIVE

We assessed the impacts of quantity and type of dietary protein on CVD risk factors.

DATA SOURCES

A database search was conducted in PubMed, Embase, CINAHL, Web of Science, and Cochrane Library and a total of 100 articles met the eligibility criteria.

DATA EXTRACTION

Extracted data from 100 articles were analyzed using standard meta-analysis, and 41 articles were also analyzed using network meta-analysis.

DATA ANALYSIS

In the standard meta-analysis, an HPD had significant favorable effects on systolic blood pressure (SBP) (mean difference [MD] = -1.51 mmHg; 95% CI: -2.77, -0.25), diastolic blood pressure (DBP) (MD = -1.08 mmHg; 95% CI: -1.81, -0.35), and flow-mediated dilation (MD = 0.78%; 95% CI: 0.09, 1.47) compared with lower protein diets. The further network meta-analysis supported that the high-protein, high-carbohydrate, low-fat diet was the most recommended diet to ensure a maximum decrease in SBP, DBP, total cholesterol (TC), and low-density-lipoprotein cholesterol (LDL-C). In comparison to animal-protein-rich diets, plant-protein-rich diets (PPRs) exhibited a significant favorable effects on improving TC (MD = -0.12 mmol/L; 95% CI: -0.19, -0.05), triglyceride (MD = -0.05 mmol/L; 95% CI: -0.09, -0.01), LDL-C (MD = -0.11 mmol/L; 95% CI: -0.18, -0.04), and high-density-lipoprotein cholesterol (MD = 0.03 mmol/L; 95% CI: 0.02, 0.04) levels.

CONCLUSION

Consumption of HPDs and PPRs supports improvements in vascular health and lipid-lipoprotein profiles, respectively. Furthermore, macronutrient composition should be carefully designed in the dietary approach to maximize the effectiveness of HPDs in improving CVD risk factors.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022369931.

Improving glycemic control via heat therapy in older adults at risk for Alzheimer's disease (FIGHT-AD): a pilot study

Impaired glycemic control increases the risk of type 2 diabetes (T2D) and Alzheimer's disease (AD). Heat therapy (HT), via hot water immersion (HWI), has shown promise in improving shared mechanisms implicated in both T2D and AD, like blood glucose regulation, insulin sensitivity, and inflammation. The potential for HT to improve brain health in individuals at risk for AD has not been examined. This pilot study aimed to assess the feasibility and adherence of using HT in cognitively healthy older individuals at risk for AD due to existing metabolic risk factors. Participants underwent 4 wk of HT (three sessions/week) via HWI, alongside cognitive screening, self-reported sleep characterization, glucose tolerance tests, and MRI scans pre- and postintervention. A total of 18 participants (9 males, 9 females; mean age: 71.1 ± 3.9 yr), demonstrating metabolic risk, completed the intervention. Participant adherence for the study was 96% (8 missed sessions out of 216 total sessions), with one study-related mild adverse event (mild dizziness/nausea). Overall, the research participants responded to a postintervention survey saying they enjoyed participating in the study and it was not a burden on their schedules. Secondary outcomes of the HT intervention demonstrated significant changes in mean arterial pressure, diastolic blood pressure, and cerebral blood flow (P < 0.05), with a trend toward improved body mass index (P = 0.06). Future studies, including longer durations and a thermoneutral control group, are needed to fully understand heat therapy's impact on glucose homeostasis and the potential to improve brain health.NEW & NOTEWORTHY Our pilot study demonstrated promising results for heat therapy (HT) via hot water immersion in older adults at risk for Alzheimer's disease due to metabolic factors. Despite a relatively short intervention, significant improvements in mean arterial pressure, diastolic blood pressure, and cerebral blood flow postintervention were observed. High participant adherence, overall satisfaction, and minimal adverse events suggest HT's feasibility. These findings highlight HT's potential as an effective alternative intervention for cardiometabolic dysfunction in at-risk populations.

Engineered endothelium model enables recapitulation of vascular function and early atherosclerosis development

Human health relies heavily on the vascular endothelium. Here, we propose a novel engineered endothelium model (EEM), which recapitulated both normal vascular function and pathology. An artificial basement membrane (aBM), where porous polyvinyl alcohol hydrogel was securely integrated with human fibroblast-derived, decellularized extracellular matrix on both sides was fabricated first and followed by endothelial cells (ECs) and pericytes (PCs) adhesion, respectively. Our EEM formed robust adherens junction (VE-cad) and built an impermeable barrier with time, along with the nitric oxide (NO) secretion. In our EEM, ECs and PCs interacted each other via aBM and led to hemoglobin alpha 1 (Hb-α1) development, which was involved in NO control and was strongly interconnected with VE-cad as well. A resilient property of EEM under inflammatory milieu was also confirmed by VE-cad and barrier recovery with time. In particular interest, foam cells formation, a hallmark of atherosclerotic initiation was successfully recapitulated in our EEM, where a series of sequential events were confirmed: human monocytes adhesion, transendothelial migration, and oxidized low-density lipoprotein uptake by macrophages. Collectively, our EEM is excellent in recapitulating not only normal endothelium but early pathologic one, thereby enabling EEM to be a physiologically relevant model for vascular study and disease modeling.

The Role of Serum Free Fatty Acids in Endothelium-Dependent Microvascular Function

BACKGROUND

Elevated serum free fatty acid (FFA) concentration is associated with insulin resistance and is a hallmark of metabolic syndrome. A pathological feature of insulin resistance is impaired endothelial function.

OBJECTIVE

To investigate the effect of FFA reduction with either acipimox, a nicotinic acid derivative that impairs lipolysis, or salsalate, a salicylate that reduces basal and inflammation-induced lipolysis, on insulin-mediated endothelium-dependent vasodilation.

METHODS

This was a post hoc, combined analysis of two randomised, double-blind, placebo-controlled crossover trials. Sixteen subjects were recruited (6 with metabolic syndrome and 10 controls) and randomised to acipimox 250 mg orally every 6 h for 7 days or placebo. Nineteen subjects were recruited (13 with metabolic syndrome and 6 controls) and randomised to receive salsalate 4.5 g/day for 4 weeks or placebo. The primary outcome was the association between FFA concentration and insulin-mediated vasodilation, measured by venous-occlusion strain-gauge plethysmography at baseline and following FFA modulation with the study drugs.

RESULTS

At baseline, FFA concentration (R = -0.35, p = 0.043) and insulin sensitivity (HOMA-IR: R = -0.42, p = 0.016, Adipo-IR: R = -0.39, p = 0.025) predicted insulin-mediated vasodilation. FFA levels were significantly reduced after drug pretreatment (0.604 vs. 0.491 mmol/L, p = 0.036) while insulin levels, insulin sensitivity and inflammatory markers were unchanged. Despite a reduction in circulating FFA with drug therapy, neither insulin-stimulated vasodilation nor insulin sensitivity improved.

CONCLUSIONS

Short-term reduction of FFA concentration does not improve insulin-stimulated vasodilation in patients with metabolic syndrome.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00759291 and NCT00760019 (formerly NCT00762827).

METTL3-mediated m6A modification of EGR1 mRNA promotes T2DM vasculopathy

Vascular endothelial dysfunction is one of the leading causes of developing vascular lesions in Type 2 diabetes mellitus (T2DM). In the development of vascular lesions, when endothelial cells are stimulated by hyperglycemia, inflammation and other external conditions, endothelial cell dysfunction will occur, which promotes endothelial cells to lose its typical phenotype and gain mesenchymal characteristics, with the occurrence of endothelial-to-mesenchymal transition (EndMT). At the same time promote endothelial cell proliferation and migration, induce vascular injury. m6A methylation modification enzyme METTL3 is involved in the development of vascular lesions in T2DM. However, the mechanisms by which METTL3 is involved in T2DM vascular lesions are unclear. In this study, we induced T2DM vascular lesions in human umbilical vein endothelial cells (HUVECs) mimicking high glucose and TNF-α (H + T) levels. The effects of METTL3 on HUVECs EndMT, proliferation and migration have been revealed. Protein expression of endothelial calmodulin (VE-Cadherin) and smooth muscle actin (α-SMA) was visualised by western blot and immunofluorescence techniques to evaluate the occurrence of EndMT. In addition, MeRIP-seq revealed a METTL3-mediated m6A modification profile. MeRIP-qPCR combined with m6A site prediction verified the methylation levels of downstream targets and identified EGR1 as a target of METTL3. Activation of EGR1 successfully rescued EndMT in METTL3-deficient HUVECs. In summary, targeting METTL3 may become an important molecular target for intervention in diabetic vascular lesions.

Retinal vessel analysis to assess microvascular function in the healthy eye: A systematic review on the response to acute physiological and pathological stressors

The retina allows noninvasive in vivo assessment of the microcirculation. Autoregulation of the retinal microvasculature meets the changing requirements of local metabolic demand and maintains adequate blood flow. Analysis of the retinal vascular reactivity contributes to the understanding of regulatory physiology and its relationship to the systemic microcirculation. We conducted a literature review on the effect of different acute stimuli onto the retinal vasculature was conducted in accordance with the PRISMA guidelines. A literature search between 1-1-2005 and 17-10-2022 was performed in Medline, Embase, Web of Science and the Cochrane Library. We report the retinal vascular behavior of healthy individuals in response to both physiological and pathological stressors in 106 included articles. We provide ables of methodological characteristics for each stressor. Hypoxia, hypercapnia, high altitude, flicker light stimulation, rise of core temperature, blood pressure lowering, and the condition immediately after endurance exercise associate with larger retinal vessels. Hyperoxia, hypocapnia, blood pressure rise (Bayliss effect), and the condition during isometric exercise associate with smaller retinal vessels. The retinal vasculature is highly reactive to physiological and pathological stressors. This autoregulatory capacity is hypothesized to be a source of biomarkers for vascular health. Dynamic and static retinal vessel analysis are noninvasive methods to assess this (micro)vascular function. Exploring its diagnostic potential and application into clinical practice requires the development of standardized assessment methods, for which some recommendations are made.

Systematic Review of Interleukin-35 in Endothelial Dysfunction: A New Target for Therapeutic Intervention

Endothelial dysfunction is a significant factor in the pathogenesis of various diseases. In pathological states, endothelial cells (ECs) undergo activation, resulting in dysfunction characterized by the stimulation of inflammatory responses, oxidative stress, cell proliferation, blood coagulation, and vascular adhesions. Interleukin-35 (IL-35), a novel member of the IL-12 family, is primarily secreted by regulatory T cells (Tregs) and regulatory B cells (Bregs). The role of IL-35 in immunomodulation, antioxidative stress, resistance to apoptosis, control of EC activation, adhesion, and angiogenesis in ECs remains incompletely understood, as the specific mechanisms of IL-35 action and its regulation have yet to be fully elucidated. Therefore, this systematic review aims to comprehensively investigate the impact of IL-35 on ECs and their physiological roles in a range of conditions, including cardiovascular diseases, tumors, sepsis, and rheumatoid arthritis (RA), with the objective of elucidating the potential of IL-35 as a therapeutic target for these ailments.

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.

Bovine dairy products and flow mediated dilation (FMD): a systematic review of the published evidence

PURPOSE

Evidence suggests bovine dairy products may have neutral or beneficial effects on cardiometabolic health, despite being a source of saturated fat. The dairy matrix, the structure and combination of protein, fat, and other nutrients, and how they interact with each other, is purported to be responsible for these beneficial health effects. Whether this relationship extends to endothelial function, as assessed by flow mediated dilation (FMD), remains to be elucidated.

METHODS

Three electronic databases (PubMed, Embase and Cochrane Central) were searched from inception until 5th September 2024. This review included randomised controlled trials (RCT) investigating any bovine dairy intervention which considered endothelial function using FMD in humans with a non-dairy or alternative dairy control.

RESULTS

Of 4,220 records identified, 18 reports from 11 RCT including 508 (53.3% male) participants, examined endothelial function by FMD and were eligible for evidence synthesis. Eight papers reported an improvement, nine reported no effect and one reported a decrease in FMD. The greatest effects were found in those with impaired health at baseline, with whey protein and high dairy intakes observed to be most beneficial.

CONCLUSION

Bovine dairy intake has neutral or beneficial effects on cardiometabolic health. This review demonstrates that this relationship extends to endothelial function as assessed by FMD. Whey protein and high dairy intakes may be most effective, although further high quality RCT in this area are warranted.

Quercetin alleviates endothelial dysfunction in preeclampsia by inhibiting ferroptosis and inflammation through EGFR binding

Preeclampsia (PE) is a pregnancy-specific complication and there remains no effective treatment. Given the limitations on medication use during pregnancy, exploring natural, safe, and effective drugs for PE is worthwhile. We investigate the causal relationship between ferroptosis, inflammation, and PE, and determine the protective effects of quercetin (QCT), a representative compound that is classified as a flavanol, against endothelial dysfunction. Then, the target of QCT is predicted and verified. The prophylactic addition of a low dose of QCT rescues endothelial dysfunction, aiding in endothelial repair. Furthermore, QCT alleviates PE-like maternal manifestations and endothelial dysfunction in the placenta of the selective reduced uteroplacental perfusion (sRUPP) rat model through binding to the epidermal growth factor receptor (EGFR). The potential applications of QCT are expanded, offering the possibility of further development as a safe and effective preventive molecule for PE.

The Effect of Sleep Disruption on Cardiometabolic Health

Sleep disruption has emerged as a significant public health concern with profound implications for metabolic health. This review synthesizes current evidence demonstrating the intricate relationships between sleep disturbances and cardiometabolic dysfunction. Epidemiological studies have consistently demonstrated that insufficient sleep duration (<7 h) and poor sleep quality are associated with increased risks of obesity, type 2 diabetes, and cardiovascular disease. The underlying mechanisms are multifaceted, involving the disruption of circadian clock genes, alterations in glucose and lipid metabolism, the activation of inflammatory pathways, and the modulation of the gut microbiome. Sleep loss affects key metabolic regulators, including AMPK signaling and disrupts the secretion of metabolic hormones such as leptin and ghrelin. The latest evidence points to the role of sleep-induced changes in the composition and function of gut microbiota, which may contribute to metabolic dysfunction through modifications in the intestinal barrier and inflammatory responses. The NLRP3 inflammasome and NF-κB signaling pathways have been identified as crucial mediators linking sleep disruption to metabolic inflammation. An understanding of these mechanisms has significant implications for public health and clinical practice, suggesting that improving sleep quality could be an effective strategy for preventing and treating cardiometabolic disorders in modern society.

Potential preservative mechanisms of cardiac rehabilitation pathways on endothelial function in coronary heart disease

Cardiac rehabilitation, a comprehensive exercise-based lifestyle and medical management, is effective in decreasing morbidity and improving life quality in patients with coronary heart disease. Endothelial function, an irreplaceable indicator in coronary heart disease progression, is measured by various methods in traditional cardiac rehabilitation pathways, including medicinal treatment, aerobic training, and smoking cessation. Nevertheless, studies on the effect of some emerging cardiac rehabilitation programs on endothelial function are limited. This article briefly reviewed the endothelium-beneficial effects of different cardiac rehabilitation pathways, including exercise training, lifestyle modification and psychological intervention in patients with coronary heart disease, and related experimental models, and summarized both uncovered and potential cellular and molecular mechanisms of the beneficial roles of various cardiac rehabilitation pathways on endothelial function. In exercise training and some lifestyle interventions, the enhanced bioavailability of nitric oxide, increased circulating endothelial progenitor cells (EPCs), and decreased oxidative stress are major contributors to preventing endothelial dysfunction in coronary heart disease. Moreover, the preservation of endothelial-dependent hyperpolarizing factors and inflammatory suppression play roles. On the one hand, to develop more endothelium-protective rehabilitation methods in coronary heart disease, adequately designed and sized randomized multicenter clinical trials should be advanced using standardized cardiac rehabilitation programs and existing assessment methods. On the other hand, additional studies using suitable experimental models are warranted to elucidate the relationship between some new interventions and endothelial protection in both macro- and microvasculature.

Risk of Type 1 Diabetes Mellitus in SARS-CoV-2 Patients

Recent studies have found that a link between people with type 1 diabetes mellitus (T1DM) are at higher risk of morbidity as well as mortality from COVID-19 infection, indicating a need for vaccination. T1DM appears to impair innate and adaptive immunity. The overabundance of pro-inflammatory cytokines produced in COVID-19 illness that is severe and potentially fatal is known as a "cytokine storm." Numerous cohorts have revealed chronic inflammation as a key risk factor for unfavorable COVID-19 outcomes. TNF-α, interleukin (IL)-1a, IL-1, IL-2, IL-6, and other cytokines were found in higher concentrations in patients with T1DM. Even more importantly, oxidative stress contributes significantly to the severity and course of COVID- 19's significant role in the progression and severity of COVID-19 diseases. Severe glucose excursions, a defining characteristic of type 1 diabetes, are widely recognized for their potent role as mediating agents of oxidative stress via several routes, such as heightened production of advanced glycation end products (AGEs) and activation of protein kinase C (PKC). Furthermore, persistent endothelial dysfunction and hypercoagulation found in T1DM may impair microcirculation and endothelium, which could result in the development of various organ failure and acute breathing syndrome.

Netrin1-Enriched Exosomes From Genetically Modified ADSCs as a Novel Treatment for Diabetic Limb Ischemia

Diabetic limb ischemia (DLI) is a frequent complication of diabetes and the leading cause of non-traumatic amputation. Traditional treatments like stent placement and bypass surgery may not suit all patients. Exosome transplantation has emerged as a promising therapy. Netrin1, a protective cardiovascular factor, has an unclear role in DLI. This study investigates the role of Netrin1 in DLI patients and evaluates the therapeutic potential of exosomes derived from Netrin1-overexpressing adipose-derived stem cells (N-ADSCs). The expression of Netrin1 is significantly decreased in both endothelial cells and serum of DLI patients, highlighting its potential as a biomarker or therapeutic target. In vitro, Netrin1-enriched exosomes (N-Exos) promoted human umbilical vein endothelial cell (HUVEC) proliferation, migration, tube formation, and increased resistance to apoptosis under high glucose conditions. These protective effects are mediated through PI3K/AKT/eNOS and MEK/ERK pathways, and N-Exos further facilitated macrophage polarization from M1 to M2. In vivo, N-Exos demonstrates superior therapeutic effects over ADSC exosomes (Exos), including enhanced angiogenesis, improved collateral artery remodeling, reduced inflammation, and muscle protection. Collectively, these findings identify Netrin1 as a critical factor in DLI and underscore its significance in disease progression and therapeutic strategies. N-Exos offers a promising non-cellular therapeutic approach for the treatment of DLI.

Natural Products to Promote Vascular Health

Maintaining good vascular health is a major component in healthy ageing as it reduces the risk of cardiovascular diseases. Endothelial dysfunction, in particular, is a key mechanism in the development of major cardiovascular diseases including hypertension, atherosclerosis and diabetes. Recently, endothelial senescence has emerged as a pivotal early event in age-related endothelial dysfunction. Endothelial function is characterized by an imbalance between the endothelial formation of vasoprotective mechanisms, including the formation of nitric oxide (NO) and endothelium-dependent hyperpolarization responses, and an increased level of oxidative stress involving several pro-oxidant enzymes such as NADPH oxidases and, often also, the appearance of cyclooxygenase-derived vasoconstrictors. Pre-clinical studies have indicated that natural products, in particular several polyphenol-rich foods, can trigger activating pathways in endothelial cells promoting an increased formation of NO and endothelium-dependent hyperpolarization. In addition, some can even exert beneficial effects on endothelial senescence. Moreover, some of these products have been associated with the prevention and/or improvement of established endothelial dysfunction in several experimental models of cardiovascular diseases and in humans with cardiovascular diseases. Therefore, intake of certain natural products, such as dietary and plant-derived polyphenol-rich products, appears to be an attractive approach for a healthy vascular system in ageing.

Uric Acid and Atherosclerosis in Patients with Chronic Kidney Disease: Recent Progress, Mechanisms, and Prospect

Background

Chronic kidney disease (CKD) is a prevalent global health concern, significantly linked to increased cardiovascular morbidity and mortality. Among various risk factors, uric acid (UA) has emerged as a potentially modifiable contributor to cardiovascular complications in CKD patients.

Summary

Elevated serum uric acid levels frequently occur in individuals with CKD and are associated with the development of atherosclerosis (AS). Uric acid has been demonstrated to exacerbate inflammatory processes, promote oxidative stress, and cause endothelial dysfunction, which are critical factors that drive the formation of atherosclerotic plaques. Furthermore, high uric acid levels can worsen renal function, establishing a detrimental cycle that amplifies cardiovascular risk.

Key Messages

This review investigates the complex interconnection between UA and AS in patients with CKD, highlighting the underlying mechanisms and therapeutic considerations. A more profound comprehension of this relationship is essential for enhancing cardiovascular health and outcomes in this vulnerable population.

Alcohol-induced gut microbial reorganization and associated overproduction of phenylacetylglutamine promotes cardiovascular disease

The mechanism(s) underlying gut microbial metabolite (GMM) contribution towards alcohol-mediated cardiovascular disease (CVD) is unknown. Herein we observe elevation in circulating phenylacetylglutamine (PAGln), a known CVD-associated GMM, in individuals living with alcohol use disorder. In a male murine binge-on-chronic alcohol model, we confirm gut microbial reorganization, elevation in PAGln levels, and the presence of cardiovascular pathophysiology. Fecal microbiota transplantation from pair-/alcohol-fed mice into naïve male mice demonstrates the transmissibility of PAGln production and the CVD phenotype. Independent of alcohol exposure, pharmacological-mediated increases in PAGln elicits direct cardiac and vascular dysfunction. PAGln induced hypercontractility and altered calcium cycling in isolated cardiomyocytes providing evidence of improper relaxation which corresponds to elevated filling pressures observed in vivo. Furthermore, PAGln directly induces vascular endothelial cell activation through induction of oxidative stress leading to endothelial cell dysfunction. We thus reveal that the alcohol-induced microbial reorganization and resultant GMM elevation, specifically PAGln, directly contributes to CVD.

E-cigarettes and arterial health: A review of the link between vaping and atherosclerosis progression

Recent studies have suggested an evolving understanding of the association between vaping, specifically electronic cigarette (e-cigarette) use, and the progression of atherosclerosis, a significant contributor to cardiovascular disease. Despite the prevailing perception of vaping as a safer alternative to traditional tobacco smoking, accumulating evidence suggests that the aerosols emitted by e-cigarettes contain harmful constituents that may promote endothelial dysfunction, oxidative stress, inflammation, and dyslipidemia-key mechanisms implicated in atherosclerosis pathogenesis. While past research, including experimental studies and clinical investigations, has shed light on the potential cardiovascular risks associated with vaping, gaps in knowledge persist. Future research endeavors should focus on interpreting the long-term effects of vaping on atherosclerosis development and progression, exploring the impact of different e-cigarette formulations and user demographics, and identifying effective strategies for mitigating the cardiovascular consequences of vaping. By identifying and addressing these research gaps, we can enhance our understanding of the cardiovascular implications of vaping and inform evidence-based interventions and policies to safeguard public health.

Succinate Regulates Endothelial Mitochondrial Function and Barrier Integrity

Endothelial dysfunction is a hallmark of several pathological conditions, including cancer, cardiovascular disease and inflammatory disorders. In these conditions, perturbed TCA cycle and subsequent succinate accumulation have been reported. The role of succinate as a regulator of immunological responses and inflammation is increasingly being recognized. Nevertheless, how endothelial cell function and phenotype are altered by elevated intracellular succinate has not been addressed yet. Thus, we employed numerous in vitro functional assays using primary HUVECs and diethyl succinate (DES), a cell membrane-permeable succinate analogue. An MTS assay 1 h post stimulation with DES suggested reduced metabolic activity in HUVECs. Concurrently, elevated production of ROS, including mitochondrial superoxide, and a reduction in mitochondrial membrane potential were observed. These findings were corroborated by Seahorse mito-stress testing, which revealed that DES acutely lowered the OCR, maximal respiration and ATP production. Given the link between mitochondrial stress and apoptosis, we examined important survival signalling pathways. DES transiently reduced ERK1/2 phosphorylation, a response that was followed by a skewed pro-apoptotic shift in the BAX to BCL2L1 gene expression ratio, which coincided with upregulating VEGF gene expression. This indicated an induction of mixed pro-apoptotic and pro-survival signals in the cell. However, the BAX/BCL-XL protein ratio was unchanged, suggesting that the cells did not commit themselves to apoptosis. An MTS assay, caspase 3/7 activity assay and annexin V/propidium iodide staining confirmed this finding. By contrast, stimulation with DES induced acute endothelial barrier permeability, forming intercellular gaps, altering cell size and associated actin filaments without affecting cell count. Notably, during overnight DES exposure gradual recovery of the endothelial barrier and cell sprouting was observed, alongside mitochondrial membrane potential restoration, albeit with sustained ROS production. COX-2 inhibition and EP4 receptor blockade hindered barrier restoration, implicating a role of COX-2/PGE2/EP4 signalling in this process. Interestingly, ascorbic acid pre-treatment prevented DES-induced acute barrier disruption independently from ROS modulation. In conclusion, succinate acts as a significant regulator of endothelial mitochondrial function and barrier integrity, a response that is counterbalanced by upregulated VEGF and prostaglandin production by the endothelial cells.

Potential of Anthocyanin-rich Products to Prevent and Improve Endothelial Function and Senescence: Focus on Anthocyanins

Endothelial dysfunction is a pivotal early event in the development of major cardiovascular diseases including hypertension, atherosclerosis, diabetes, and aging. The alteration of the endothelial function is often triggered by an imbalance between the endothelial formation of vasoprotective factors, including nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH), and vasocontracting factors, such as arachidonic acid-derived mediators generated by cyclooxygenases, and an increased level of oxidative stress. Recently, endothelial senescence was reported to be an early trigger of endothelial dysfunction. Preclinical studies indicate that polyphenol-rich food, including anthocyanin-rich products, can activate pathways promoting an increased formation of vasoprotective factors and can prevent the induction of endothelial dysfunction in endothelial cells and isolated blood vessels. Similarly, intake of anthocyanin-rich products has been associated with the prevention and/or the improvement of an endothelial dysfunction in several experimental models of cardiovascular diseases, including physiological aging. Moreover, clinical data indicate that polyphenol-rich and anthocyanin-rich products can improve endothelial function and vascular health in humans with cardiovascular diseases. The present review will discuss both experimental and clinical evidence indicating that several polyphenol-rich foods and natural products, and especially anthocyanin-rich products, can promote endothelial and vascular health, as well as the underlying mechanisms.

The Effect of Dark Chocolate Consumption on Arterial Function in Endurance Male Runners: Prospective Cohort Study

Foods rich in polyphenols have beneficial effects on health. This study aimed to examine the impact of dark chocolate on endurance runners' arterial function. Forty-six male amateur runners, aged 25-55, participated. The initial assessments included clinical testing, arterial stiffness measurements, and a cardiopulmonary exercise test. The participants then consumed 50 g of dark chocolate (70% cocoa) daily for two weeks, maintaining their usual training routine. After this period, the baseline assessment was repeated. The results showed significant improvements. Pulse wave velocity decreased by 11.82% (p < 0.001), and augmentation index by 19.47% (p < 0.001). Systolic brachial blood pressure reduced by 2.12% (p < 0.05), diastolic by 2.79% (p < 0.05), and mean pressure by 2.41% (p < 0.05). Central arterial pressure also decreased, with systolic by 1.24% (p < 0.05), diastolic by 2.80% (p < 0.05), and mean pressure by 2.43% (p < 0.05). Resting heart rate increased by 4.57% (p < 0.05) and left ventricular ejection time decreased by 4.89% (p < 0.05), particularly in athletes over 40. Exercise time increased by 2.16% (p < 0.05), heart rate (max) by 1.15% (p < 0.05), VO2max by 2.31% (p < 0.05), and anaerobic threshold shifted by 6.91% (p < 0.001) in exercise time and 6.93% (p < 0.001) in VO2max. In conclusion, dark chocolate improves arterial function in endurance runners, enhancing vascular health.

Endothelial Dysfunction: Molecular Mechanisms and Therapeutic Strategies in Kawasaki Disease

The endothelium plays a key role in regulating vascular homeostasis by responding to a large spectrum of chemical and physical stimuli. Vasculitis is a group of inflammatory conditions affecting the vascular bed, and it is known that they are strongly linked to endothelial dysfunction (ED). Kawasaki disease (KD) is one childhood systemic vasculitis, and it represents the leading cause of acquired cardiac disease in children due to coronary damage and subsequent cardiovascular (CV) morbidity and mortality. We aimed to focus on the actual knowledge of ED in the pathogenesis of KD and its practical implications on therapeutical strategies to limit cardiovascular complications. Understanding ED in KD provides insight into the underlying mechanisms and identifies potential therapeutic targets to mitigate vascular damage, ultimately improving cardiovascular outcomes in both the acute and chronic stages of the disease. However, research gaps remain, particularly in translating findings from animal models into clinical applications for cardiovascular lesions and related morbidity in KD patients.

Endothelial Dysfunction Markers in Ovarian Cancer: VTE Risk and Tumour Prognostic Outcomes

Ovarian cancer (OC) presents daunting lethality rates worldwide, with frequent late-stage diagnosis and chemoresistance, highlighting the need for improved prognostic approaches. Venous thromboembolism (VTE), a major cancer mortality factor, is partially driven by endothelial dysfunction (ED). ED's pro-inflammatory state fosters tumour progression, suggesting a VTE-independent link between ED and cancer. Given this triad's interplay, ED markers may influence OC behaviour and patients' prognosis. Thus, the impact of ED-related genes and single-nucleotide polymorphisms (SNPs) on OC-related VTE and patient thrombogenesis-independent prognosis was investigated. NOS3 upregulation was linked to lower VTE incidence (χ2, p = 0.013), while SELP upregulation was associated with shorter overall survival (log-rank test, p = 0.048). Dismissing patients with VTE before OC diagnosis, SELP rs6136 T allele carriers presented lower progression-free survival (log-rank test, p = 0.038). Nevertheless, due to the SNP minor allele underrepresentation, further investigation is required. Taken together, ED markers seem to exhibit roles that depend on the clinical context, such as tumour-related thrombogenesis or cancer prognosis. Validation with larger cohorts and more in-depth functional studies are needed for data clarification and potential therapeutic strategies exploitation to tackle cancer progression and thrombosis in OC patients.

Enhanced vasoconstriction in sickle cell disease is dependent on ETA receptor activation

Sickle cell disease (SCD) carries a significant risk for poor vascular health and vascular dysfunction. High levels of vascular reactive oxygen species (ROS) as well as elevated plasma endothelin-1 (ET-1), a potent vasoconstrictor with actions via the ETA receptor, are both common phenotypes in SCD. Alpha-1 adrenergic receptor activation is a major mediator of stress-induced vasoconstriction. However, the mechanism of the SCD enhanced vasoconstrictive response is unknown. We hypothesized that SCD induces enhanced alpha-1 adrenergic mediated vasoconstriction through the ET-1/ETA receptor pathway in arterial tissues. Utilizing humanized SCD (HbSS) and genetic control (HbAA) mice, alpha-1a, but not alpha-1b or alpha-1d, receptor expression was significantly greater in aortic tissue from HbSS mice compared to HbAA mice. Significantly enhanced vasoconstriction in aortic and carotid arterial segments were observed from HbSS mice compared with HbAA mice. Treatment with ambrisentan, a selective ETA receptor antagonist, and a ROS scavenger normalized the aortic vasoconstrictive response in HbSS mice. In a randomized translational study, patients with SCD were treated with placebo or ambrisentan for 3 months, with the treatment group showing an increase in the percent brachial arterial diameter. Taken together, these data suggest that the ETA receptor pathway interaction with the adrenergic receptor pathway contributes to enhanced aortic vasoconstriction in SCD. Findings indicate the potential of ETA antagonism as a therapeutic avenue for improving vascular health in SCD.

Low-Intensity Resistance Exercise in Cardiac Rehabilitation: A Narrative Review of Mechanistic Evidence and Clinical Implications

Cardiac rehabilitation, a multi-component intervention designed to mitigate the impact of cardiovascular disease, often underutilises low-intensity resistance exercise despite its potential benefits. This narrative review critically examines the mechanistic and clinical evidence supporting the incorporation of low-intensity resistance exercise into cardiac rehabilitation programmes. Research indicates that low-intensity resistance exercise induces hypertrophic adaptations by maximising muscle fibre activation through the size principle, effectively recruiting larger motor units as it approaches maximal effort. This activation promotes adaptation in both type I and II muscle fibres, resulting in comparable increases in myofibrillar protein synthesis and phosphorylation of key signalling proteins when compared to high-intensity resistance exercise. Low-intensity resistance exercise provides equivalent improvements in muscular strength and hypertrophy compared to high-intensity protocols while addressing barriers to participation, such as concerns about safety and logistical challenges. By facilitating engagement through a more accessible exercise modality, low-intensity resistance exercise might improve adherence rates and patient outcomes in cardiac rehabilitation. Additionally, the ability of low-intensity resistance exercise to address sarcopenia and frailty syndrome, significant determinants of cardiovascular disease progression, can enhance the recovery and overall quality of life for patients. This review establishes evidence-based recommendations for the inclusion of low-intensity resistance exercise in cardiac rehabilitation, offering a promising pathway to enhance the effectiveness of these programmes.

Closer look at circulating nitric oxide levels and their association with polycystic ovary syndrome: A meta-analytical exploration

Background

Polycystic ovary syndrome (PCOS) casts a wide shadow over the reproductive health of millions of women worldwide, emerging as one of the most complex and multifaceted endocrine disorders. In addition, nitric oxide (NO) stands out as a pivotal signaling molecule, orchestrating a symphony of physiological processes.

Objective

This meta-analysis aims to elucidate the association between NO levels and PCOS, investigate the potential of NO as a biomarker for PCOS diagnosis, and evaluate its clinical significance.

Materials and Methods

A systematic review was conducted in several electronic databases, including PubMed, Web of Science, Cochrane Library, Scopus, EMBASE, and Google Scholar, to identify relevant studies published up to January 2024. Standardized mean difference and 95% CI were calculated using a random effects model to assess the overall effect size. Meta-regressions and subgroup analysis were performed to investigate sources of heterogeneity.

Results

A meta-analysis of 14 studies with 1171 participants showed that NO levels were significantly lower in the PCOS group than in the control group. The pooled analysis yielded a standardized mean difference of -0.482; 95% CI: -0.908 to -0.056; p = 0.027. Subgroup analyses further demonstrated variations in NO levels between different PCOS phenotypes and in relation to metabolic parameters.

Conclusion

This meta-analysis provides evidence for an association between PCOS and dysregulated NO levels and suggests a potential role of NO as a biomarker in the diagnosis and pathogenesis of PCOS.

Vascular chemerin from PVAT contributes to norepinephrine and serotonin-induced vasoconstriction and vascular stiffness in a sex-dependent manner

The adipokine chemerin supports normal blood pressure and contributes to adiposity-associated hypertension, evidenced by falls in mean arterial pressure in Dahl SS rats given an antisense oligonucleotide against chemerin. In humans, circulating chemerin is positively associated with hypertension and aortic stiffness. Mechanisms of chemerin's influence on vascular health and disease remain unknown. We identified chemerin production in the vasculature-the blood vessel and its perivascular adipose tissue (PVAT). Here, using RNAScope, qPCR, isometric contractility, high-frequency ultrasound imaging, and Western blot in the Dahl SS rat, we test the hypothesis that endogenous chemerin amplifies agonist-induced vasoconstriction through the chemerin1 receptor and that chemerin drives aortic stiffness in the thoracic aorta. CMKLR1 (chemerin1) expression was higher in the media, and Rarres2 (chemerin) expression was higher in the PVAT. Chemerin1 receptor antagonism via selective inhibitor CCX832 reduced maximal contraction to norepinephrine (NE) and serotonin (5-HT), but not angiotensin II, in isolated thoracic aorta (PVAT intact) from male Dahl SS rat. In females, CCX832 did not alter contraction to NE or 5-HT. Male, but not female, genetic chemerin knockout Dahl SS rats had lower aortic arch pulse wave velocity than wild types, indicating chemerin's role in aortic stiffness. Aortic PVAT from females expressed less chemerin protein than males, suggesting PVAT as the primary source of active chemerin. We show that chemerin made by the PVAT amplifies NE and 5-HT-induced contraction and potentially induces aortic stiffening in a sex-dependent manner, highlighting the potential for chemerin to be a key factor in blood pressure control and aortic stiffening.NEW & NOTEWORTHY Chemerin1 receptor inhibition reduced norepinephrine (NE) and 5-HT-induced vasoconstriction in males. Genetic chemerin knockout (KO) resulted in lower pulse wave velocity in males. Differences in chemerin abundance in aorta perivascular adipose tissue (APVAT) may explain sex-dependent role of chemerin.

Extracellular vesicles for delivering therapeutic agents in ischemia/reperfusion injury

Ischemia/reperfusion (I/R) injury is marked by the restriction and subsequent restoration of blood supply to an organ. This process can exacerbate the initial tissue damage, leading to further disorders, disability, and even death. Extracellular vesicles (EVs) are crucial in cell communication by releasing cargo that regulates the physiological state of recipient cells. The development of EVs presents a novel avenue for delivering therapeutic agents in I/R therapy. The therapeutic potential of EVs derived from stem cells, endothelial cells, and plasma in I/R injury has been actively investigated. Therefore, this review aims to provide an overview of the pathological process of I/R injury and the biophysical properties of EVs. We noted that EVs serve as nontoxic, flexible, and multifunctional carriers for delivering therapeutic agents capable of intervening in I/R injury progression. The therapeutic efficacy of EVs can be enhanced through various engineering strategies. Improving the tropism of EVs via surface modification and modulating their contents via preconditioning are widely investigated in preclinical studies. Finally, we summarize the challenges in the production and delivery of EV-based therapy in I/R injury and discuss how it can advance. This review will encourage further exploration in developing efficient EV-based delivery systems for I/R treatment.

Effects of Mediterranean Diet on Endothelial Reactivity in Individuals with High Cardiometabolic Risk: A Randomized Controlled Parallel-Group Preliminary Trial

BACKGROUND

Endothelial dysfunction is recognized as an early modification involved in the pathogenesis of vascular diseases. Evidence suggests that the Mediterranean Diet (MD) is associated with endothelial function improvement and, in turn, plays an important role in atherosclerosis development and progression.

OBJECTIVES

To evaluate both acute and sustained effects of the MD on endothelial function in patients with high cardiometabolic risk.

METHODS

A total of 25 subjects were randomly assigned to either the MD group or the Control Diet (CD) group according to a single-blind, parallel-group study design. Endothelial function was evaluated through non-invasive flow-mediated dilation (FMD) measurements at baseline (T0) and after 8 weeks (Tw8) of the MD or CD intervention, under both 12 h fast condition (fasting) and 2 h post-meal resembling the assigned diet (2 h). Assessments were conducted by a blinded sonographer.

RESULTS

FMD at T0-fasting was similar between MD and CD groups (6.11% ± 0.67 vs. 7.90% ± 1.65; p = 0.266). A significant difference in FMD between MD and CD groups was observed at T0-2h (12.14% ± 1.93 vs. 4.01% ± 1.03; p = 0.004), T8w-fasting (9.76% ± 1.18 vs. 5.03% ± 0.89; p = 0.008), and T8w-2h (8.99% ± 1.22 vs. 3.86% ± 0.52; p = 0.003). Oral glucose insulin sensitivity (OGIS) at T0 correlated with FMD percent changes from T0-fasting to T0-2h (r = 0.414, p = 0.044). After adjusting for age, gender, and OGIS, MD was an independent predictor of percent changes in FMD from T0-fasting to T0-2h (β: -0.582, p = 0.003), from T0-fasting to T8w-fasting (β: -0.498, p = 0.013), and from T0-fasting to T8w-2h (β: -0.479, p = 0.018).

CONCLUSIONS

Adherence to the MD may improve endothelial function in both the short- and medium-term among patients at high cardiometabolic risk.

Circulating endothelial progenitor cells and inflammatory markers in type 1 diabetes after an acute session of aerobic exercise

Objective

To determine circulating endothelial progenitor cells (EPC) counts and levels of inflammatory markers in individuals with and without type 1 diabetes mellitus (T1DM) in response to an intense aerobic exercise session.

Subjects and methods

In total, 15 adult men with T1DM and 15 healthy individuals underwent a 30-minute aerobic exercise session on a cycle ergometer at 60% of the peak heart rate. The EPC count (CD45dim/CD34+/KDR+), tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) levels were measured before and 60 minutes after the session.

Results

We found no difference within or between groups regarding EPC counts before and after the aerobic exercise: healthy individuals, 0.02% change (95% confidence interval [CI] -0.04%-0.08%); individuals with T1DM, 0.00% (95%CI -0.01%-0.01%). We also found no difference in TNF-α levels before and after exercise in healthy individuals (210.2, interquartile range [IQR] 142.1-401.2 pg/mL and 191.3, IQR 136.4-350.5 pg/mL, respectively) and in patients with T1DM (463.8, IQR 201.4-4306.0 pg/mL and 482.7, IQR 143.8-4304.3 pg/mL, respectively). Similarly, no difference in IL-6 levels was observed before and after exercise in healthy individuals (148.2, IQR 147.5-148.6 pg/mL and 148.2, IQR 147.7-148.6 pg/mL, respectively) and individuals with T1DM (147.2, IQR 145.9-147.7 pg/mL and 147.2, IQR 146.8-147.8 pg/mL, respectively).

Conclusions

Patients with T1DM and healthy controls had comparable EPC responses to aerobic exercise, most likely due to the absence of a chronic inflammatory state.