Endothelial NOS: perspective and recent developments

Endothelial force sensing signals to parenchymal cells to regulate bile and plasma lipids

How cardiovascular activity interacts with lipid homeostasis is incompletely understood. We postulated a role for blood flow acting at endothelium in lipid regulatory organs. Transcriptome analysis was performed on livers from mice engineered for deletion of the flow-sensing PIEZO1 channel in endothelium. This revealed unique up-regulation of Cyp7a1, which encodes the rate-limiting enzyme for bile synthesis from cholesterol in hepatocytes. Consistent with this effect were increased gallbladder and plasma bile acids and lowered hepatic and plasma cholesterol. Elevated portal fluid flow acting via endothelial PIEZO1 and genetically enhanced PIEZO1 conversely suppressed Cyp7a1. Activation of hepatic endothelial PIEZO1 channels promoted phosphorylation of nitric oxide synthase 3, and portal flow-mediated suppression of Cyp7a1 depended on nitric oxide synthesis, suggesting endothelium-to-hepatocyte coupling via nitric oxide. PIEZO1 variants in people were associated with hepatobiliary disease and dyslipidemia. The data suggest an endothelial force sensing mechanism that controls lipid regulation in parenchymal cells to modulate whole-body lipid homeostasis.

Insights into the post-translational modifications in heart failure

Heart failure (HF), as the terminal manifestation of multiple cardiovascular diseases, causes a huge socioeconomic burden worldwide. Despite the advances in drugs and medical-assisted devices, the prognosis of HF remains poor. HF is well-accepted as a myriad of subcellular dys-synchrony related to detrimental structural and functional remodelling of cardiac components, including cardiomyocytes, fibroblasts, endothelial cells and macrophages. Through the covalent chemical process, post-translational modifications (PTMs) can coordinate protein functions, such as re-localizing cellular proteins, marking proteins for degradation, inducing interactions with other proteins and tuning enzyme activities, to participate in the progress of HF. Phosphorylation, acetylation, and ubiquitination predominate in the currently reported PTMs. In addition, advanced HF is commonly accompanied by metabolic remodelling including enhanced glycolysis. Thus, glycosylation induced by disturbed energy supply is also important. In this review, firstly, we addressed the main types of HF. Then, considering that PTMs are associated with subcellular locations, we summarized the leading regulation mechanisms in organelles of distinctive cell types of different types of HF, respectively. Subsequently, we outlined the aforementioned four PTMs of key proteins and signaling sites in HF. Finally, we discussed the perspectives of PTMs for potential therapeutic targets in HF.

Role of post-translational modifications of Sp1 in cardiovascular diseases

Specific protein 1 (Sp1) is pivotal in sustaining baseline transcription as well as modulating cell signaling pathways and transcription factors activity. Through interactions with various proteins, especially transcription factors, Sp1 controls the expression of target genes, influencing numerous biological processes. Numerous studies have confirmed Sp1's significant regulatory role in the pathogenesis of cardiovascular disorders. Post-translational modifications (PTMs) of Sp1, such as phosphorylation, ubiquitination, acetylation, glycosylation, SUMOylation, and S-sulfhydration, can enhance or modify its transcriptional activity and DNA-binding stability. These modifications also regulate Sp1 expression across different cell types. Sp1 is crucial in regulating non-coding gene expression and the activity of proteins in response to pathophysiological stimuli. Understanding Sp1 PTMs advances our knowledge of cell signaling pathways in controlling Sp1 stability during cardiovascular disease onset and progression. It also aids in identifying novel pharmaceutical targets and biomarkers essential for preventing and managing cardiovascular diseases.

The Unexpected Role of the Endothelial Nitric Oxide Synthase at the Neurovascular Unit: Beyond the Regulation of Cerebral Blood Flow

Nitric oxide (NO) is a highly versatile gasotransmitter that has first been shown to regulate cardiovascular function and then to exert tight control over a much broader range of processes, including neurotransmitter release, neuronal excitability, and synaptic plasticity. Endothelial NO synthase (eNOS) is usually far from the mind of synaptic neurophysiologists, who have focused most of their attention on neuronal NO synthase (nNOS) as the primary source of NO at the neurovascular unit (NVU). Nevertheless, the available evidence suggests that eNOS could also contribute to generating the burst of NO that, serving as volume intercellular messenger, is produced in response to neuronal activity in the brain parenchyma. Herein, we review the role of eNOS in both the regulation of cerebral blood flow and of synaptic plasticity and discuss the mechanisms by which cerebrovascular endothelial cells may transduce synaptic inputs into a NO signal. We further suggest that eNOS could play a critical role in vascular-to-neuronal communication by integrating signals converging onto cerebrovascular endothelial cells from both the streaming blood and active neurons.

The potential impact of periodontitis on cerebral small vessel disease

Cerebral small vessel disease (CSVD) is a term used to describe abnormalities in the intracranial microvasculature affecting small arteries, arterioles, capillaries, and venules. The etiology of these conditions is not fully understood but inflammation appears to play a significant role. Periodontal diseases have been associated with conditions such as stroke and dementia, which are clinical consequences of CSVD. Periodontitis is a highly prevalent chronic multifactorial inflammatory disease regulated by the host immune response against pathogenic bacterial colonization around the teeth. The inflammatory response and the microbial dysbiosis produce pro-inflammatory cytokines that can reach the brain and promote local changes. This review will explore the potential association between periodontitis and CSVD by assessing the impact of periodontitis-induced inflammation and periodontopathogenic bacteria on the underlying mechanisms leading to CSVD. Given the association of periodontitis with stroke and dementia, which are clinical features of CSVD, it may be possible to suggest a link with CSVD. Current evidence linking periodontitis with neuroimaging findings of CSVD enforces the possible link between these conditions.

Endothelial cell dysfunction and targeted therapeutic drugs in sepsis

Sepsis is a life-threatening organ dysfunction caused by an abnormal host response to microbial infections. During its pathogenesis, vascular endothelial cells (ECs) play a pivotal role as essential components in maintaining microcirculatory homeostasis. This article aims to comprehensively review the multifaceted physiological functions of vascular ECs, elucidate the alterations in their functionality throughout the course of sepsis, and explore recent advancements in research concerning sepsis-related therapeutic drugs targeting ECs.

Metabolic Responses to Redox Stress in Vascular Cells

Significance: Redox stress underlies numerous vascular disease mechanisms. Metabolic adaptability is essential for vascular cells to preserve energy and redox homeostasis. Recent Advances: Single-cell technologies and multiomic studies demonstrate significant metabolic heterogeneity among vascular cells in health and disease. Increasing evidence shows that reductive or oxidative stress can induce metabolic reprogramming of vascular cells. A recent example is intracellular L-2-hydroxyglutarate accumulation in response to hypoxic reductive stress, which attenuates the glucose flux through glycolysis and mitochondrial respiration in pulmonary vascular cells and provides protection against further reductive stress. Critical Issues: Regulation of cellular redox homeostasis is highly compartmentalized and complex. Vascular cells rely on multiple metabolic pathways, but the precise connectivity among these pathways and their regulatory mechanisms is only partially defined. There is also a critical need to understand better the cross-regulatory mechanisms between the redox system and metabolic pathways as perturbations in either systems or their cross talk can be detrimental. Future Directions: Future studies are needed to define further how multiple metabolic pathways are wired in vascular cells individually and as a network of closely intertwined processes given that a perturbation in one metabolic compartment often affects others. There also needs to be a comprehensive understanding of how different types of redox perturbations are sensed by and regulate different cellular metabolic pathways with specific attention to subcellular compartmentalization. Lastly, integration of dynamic changes occurring in multiple metabolic pathways and their cross talk with the redox system is an important goal in this multiomics era.

Lipid Emulsions Inhibit Labetalol-Induced Vasodilation in the Isolated Rat Aorta

Lipid emulsions are used as adjuvant drugs to alleviate intractable cardiovascular collapse induced by drug toxicity. We aimed to examine the effect of lipid emulsions on labetalol-induced vasodilation and the underlying mechanism in the isolated rat aorta. We studied the effects of endothelial denudation, NW-nitro-l-arginine methyl ester (l-NAME), calmidazolium, methylene blue, 1H-[1,2,4]oxadiazolo[4,3-a] quinoxalin-1-one (ODQ), and lipid emulsions on labetalol-induced vasodilation. We also evaluated the effects of lipid emulsions on cyclic guanosine monophosphate (cGMP) formation, endothelial nitric oxide synthase (eNOS) phosphorylation, and endothelial calcium levels induced by labetalol. Labetalol-induced vasodilation was higher in endothelium-intact aortas than that in endothelium-denuded aortas. l-NAME, calmidazolium, methylene blue, and ODQ inhibited labetalol-induced vasodilation in endothelium-intact aortas. Lipid emulsions inhibited labetalol-induced vasodilation in endothelium-intact and endothelium-denuded aortas. l-NAME, ODQ, and lipid emulsions inhibited labetalol-induced cGMP formation in endothelium-intact aortas. Lipid emulsions reversed the stimulatory and inhibitory eNOS (Ser1177 and Thr495) phosphorylation induced by labetalol in human umbilical vein endothelial cells and inhibited the labetalol-induced endothelial calcium increase. Moreover, it decreased labetalol concentration. These results suggest that lipid emulsions inhibit vasodilation induced by toxic doses of labetalol, which is mediated by the inhibition of endothelial nitric oxide release and reduction of labetalol concentration.

Graphene Far-Infrared Irradiation Can Effectively Relieve the Blood Pressure Level of Rat Untr-HT in Primary Hypertension

Graphene, when electrified, generates far-infrared radiation within the wavelength range of 4 μm to 14 μm. This range closely aligns with the far-infrared band (3 μm to 15 μm), which produces unique physiological effects. Contraction and relaxation of vascular smooth muscle play a significant role in primary hypertension, involving the nitric oxide-soluble guanylate cyclase-cyclic guanosine monophosphate pathway and the renin-angiotensin-aldosterone system. This study utilized spontaneously hypertensive rats (SHRs) as an untr-HT to investigate the impact of far-infrared radiation at specific wavelengths generated by electrified graphene on vascular smooth muscle and blood pressure. After 7 weeks, the blood pressure of the untr-HT group rats decreased significantly with a notable reduction in the number of vascular wall cells and the thickness of the vascular wall, as well as a decreased ratio of vessel wall thickness to lumen diameter. Additionally, blood flow perfusion significantly increased, and the expression of F-actin in vascular smooth muscle myosin decreased significantly. Serum levels of angiotensin II (Ang-II) and endothelin 1 (ET-1) were significantly reduced, while nitric oxide synthase (eNOS) expression increased significantly. At the protein level, eNOS expression decreased significantly, while α-SMA expression increased significantly in aortic tissue. At the gene level, expressions of eNOS and α-SMA in aortic tissue significantly increased. Furthermore, the content of nitric oxide (NO) in the SHR's aortic tissue increased significantly. These findings confirm that graphene far-infrared radiation enhances microcirculation, regulates cytokines affecting vascular smooth muscle contraction, and modifies vascular morphology and smooth muscle phenotype, offering relief for primary hypertension.

Near-Infrared II Photobiomodulation Preconditioning Ameliorates Stroke Injury via Phosphorylation of eNOS

BACKGROUND

The current management of patients with stroke with intravenous thrombolysis and endovascular thrombectomy is effective only when it is timely performed on an appropriately selected but minor fraction of patients. The development of novel adjunctive therapy is highly desired to reduce morbidity and mortality with stroke. Since endothelial dysfunction is implicated in the pathogenesis of stroke and is featured with suppressed endothelial nitric oxide synthase (eNOS) with concomitant nitric oxide deficiency, restoring endothelial nitric oxide represents a promising approach to treating stroke injury.

METHODS

This is a preclinical proof-of-concept study to determine the therapeutic effect of transcranial treatment with a low-power near-infrared laser in a mouse model of ischemic stroke. The laser treatment was performed before the middle cerebral artery occlusion with a filament. To determine the involvement of eNOS phosphorylation, unphosphorylatable eNOS S1176A knock-in mice were used. Each measurement was analyzed by a 2-way ANOVA to assess the effect of the treatment on cerebral blood flow with laser Doppler flowmetry, eNOS phosphorylation by immunoblot analysis, and stroke outcomes by infarct volumes and neurological deficits.

RESULTS

Pretreatment with a 1064-nm laser at an irradiance of 50 mW/cm2 improved cerebral blood flow, eNOS phosphorylation, and stroke outcomes.

CONCLUSIONS

Near-infrared II photobiomodulation could offer a noninvasive and low-risk adjunctive therapy for stroke injury. This new modality using a physical parameter merits further consideration to develop innovative therapies to prevent and treat a wide array of cardiovascular diseases.

Mechanosensitive membrane domains regulate calcium entry in arterial endothelial cells to protect against inflammation

Endothelial cells (ECs) in the descending aorta are exposed to high laminar shear stress, and this supports an antiinflammatory phenotype. High laminar shear stress also induces flow-aligned cell elongation and front-rear polarity, but whether these are required for the antiinflammatory phenotype is unclear. Here, we showed that caveolin-1-rich microdomains polarize to the downstream end of ECs that are exposed to continuous high laminar flow. These microdomains were characterized by high membrane rigidity, filamentous actin (F-actin), and raft-associated lipids. Transient receptor potential vanilloid (TRPV4) ion channels were ubiquitously expressed on the plasma membrane but mediated localized Ca2+ entry only at these microdomains where they physically interacted with clustered caveolin-1. These focal Ca2+ bursts activated endothelial nitric oxide synthase within the confines of these domains. Importantly, we found that signaling at these domains required both cell body elongation and sustained flow. Finally, TRPV4 signaling at these domains was necessary and sufficient to suppress inflammatory gene expression and exogenous activation of TRPV4 channels ameliorated the inflammatory response to stimuli both in vitro and in vivo. Our work revealed a polarized mechanosensitive signaling hub in arterial ECs that dampened inflammatory gene expression and promoted cell resilience.

Hypersensitive blood vessels in Clarkson disease

Idiopathic systemic capillary leak syndrome (ISCLS) is a rare, recurrent condition with dramatically increased blood vessel permeability and, therefore, induction of systemic edema, which may lead to organ damage and death. In this issue of the JCI, Ablooglu et al. showed that ISCLS vessels were hypersensitive to agents known to increase vascular permeability, using human biopsies, cell culture, and mouse models. Several endothelium-specific proteins that regulate endothelial junctions were dysregulated and thereby compromised the vascular barrier. These findings suggest that endothelium-intrinsic dysregulation underlies hyperpermeability and implicate the cytoplasmic serine/threonine protein phosphatase 2A (PP2A) as a potential drug target for the treatment of ISCLS.

Several lines of antioxidant defense against oxidative stress: antioxidant enzymes, nanomaterials with multiple enzyme-mimicking activities, and low-molecular-weight antioxidants

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are well recognized for playing a dual role, since they can be either deleterious or beneficial to biological systems. An imbalance between ROS production and elimination is termed oxidative stress, a critical factor and common denominator of many chronic diseases such as cancer, cardiovascular diseases, metabolic diseases, neurological disorders (Alzheimer's and Parkinson's diseases), and other disorders. To counteract the harmful effects of ROS, organisms have evolved a complex, three-line antioxidant defense system. The first-line defense mechanism is the most efficient and involves antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). This line of defense plays an irreplaceable role in the dismutation of superoxide radicals (O2•-) and hydrogen peroxide (H2O2). The removal of superoxide radicals by SOD prevents the formation of the much more damaging peroxynitrite ONOO- (O2•-  + NO• → ONOO-) and maintains the physiologically relevant level of nitric oxide (NO•), an important molecule in neurotransmission, inflammation, and vasodilation. The second-line antioxidant defense pathway involves exogenous diet-derived small-molecule antioxidants. The third-line antioxidant defense is ensured by the repair or removal of oxidized proteins and other biomolecules by a variety of enzyme systems. This review briefly discusses the endogenous (mitochondria, NADPH, xanthine oxidase (XO), Fenton reaction) and exogenous (e.g., smoking, radiation, drugs, pollution) sources of ROS (superoxide radical, hydrogen peroxide, hydroxyl radical, peroxyl radical, hypochlorous acid, peroxynitrite). Attention has been given to the first-line antioxidant defense system provided by SOD, CAT, and GPx. The chemical and molecular mechanisms of antioxidant enzymes, enzyme-related diseases (cancer, cardiovascular, lung, metabolic, and neurological diseases), and the role of enzymes (e.g., GPx4) in cellular processes such as ferroptosis are discussed. Potential therapeutic applications of enzyme mimics and recent progress in metal-based (copper, iron, cobalt, molybdenum, cerium) and nonmetal (carbon)-based nanomaterials with enzyme-like activities (nanozymes) are also discussed. Moreover, attention has been given to the mechanisms of action of low-molecular-weight antioxidants (vitamin C (ascorbate), vitamin E (alpha-tocopherol), carotenoids (e.g., β-carotene, lycopene, lutein), flavonoids (e.g., quercetin, anthocyanins, epicatechin), and glutathione (GSH)), the activation of transcription factors such as Nrf2, and the protection against chronic diseases. Given that there is a discrepancy between preclinical and clinical studies, approaches that may result in greater pharmacological and clinical success of low-molecular-weight antioxidant therapies are also subject to discussion.

Practical Three-Component Regioselective Synthesis of Drug-Like 3-Aryl(or heteroaryl)-5,6-dihydrobenzo[h]cinnolines as Potential Non-Covalent Multi-Targeting Inhibitors To Combat Neurodegenerative Diseases

Neurodegenerative diseases (NDs) are one of the prominent health challenges facing contemporary society, and many efforts have been made to overcome and (or) control it. In this research paper, we described a practical one-pot two-step three-component reaction between 3,4-dihydronaphthalen-1(2H)-one (1), aryl(or heteroaryl)glyoxal monohydrates (2a-h), and hydrazine monohydrate (NH2NH2•H2O) for the regioselective preparation of some 3-aryl(or heteroaryl)-5,6-dihydrobenzo[h]cinnoline derivatives (3a-h). After synthesis and characterization of the mentioned cinnolines (3a-h), the in silico multi-targeting inhibitory properties of these heterocyclic scaffolds have been investigated upon various Homo sapiens-type enzymes, including hMAO-A, hMAO-B, hAChE, hBChE, hBACE-1, hBACE-2, hNQO-1, hNQO-2, hnNOS, hiNOS, hPARP-1, hPARP-2, hLRRK-2(G2019S), hGSK-3β, hp38α MAPK, hJNK-3, hOGA, hNMDA receptor, hnSMase-2, hIDO-1, hCOMT, hLIMK-1, hLIMK-2, hRIPK-1, hUCH-L1, hPARK-7, and hDHODH, which have confirmed their functions and roles in the neurodegenerative diseases (NDs), based on molecular docking studies, and the obtained results were compared with a wide range of approved drugs and well-known (with IC50, EC50, etc.) compounds. In addition, in silico ADMET prediction analysis was performed to examine the prospective drug properties of the synthesized heterocyclic compounds (3a-h). The obtained results from the molecular docking studies and ADMET-related data demonstrated that these series of 3-aryl(or heteroaryl)-5,6-dihydrobenzo[h]cinnolines (3a-h), especially hit ones, can really be turned into the potent core of new drugs for the treatment of neurodegenerative diseases (NDs), and/or due to the having some reactionable locations, they are able to have further organic reactions (such as cross-coupling reactions), and expansion of these compounds (for example, with using other types of aryl(or heteroaryl)glyoxal monohydrates) makes a new avenue for designing novel and efficient drugs for this purpose.

Why is early-onset atrial fibrillation uncommon in patients with Duchenne muscular dystrophy? Insights from the mdx mouse

AIMS

A reduction in both dystrophin and neuronal nitric oxide synthase (NOS1) secondary to microRNA-31 (miR-31) up-regulation contributes to the atrial electrical remodelling that underpins human and experimental atrial fibrillation (AF). In contrast, patients with Duchenne muscular dystrophy (DMD), who lack dystrophin and NOS1 and, at least in the skeletal muscle, have raised miR-31 expression, do not have increase susceptibility to AF in the absence of left ventricular (LV) dysfunction. Here, we investigated whether dystrophin deficiency is also associated with atrial up-regulation of miR-31, loss of NOS1 protein, and increased AF susceptibility in young mdx mice.

METHODS AND RESULTS

Echocardiography showed normal cardiac structure and function in 12-13 weeks mdx mice, with no indication by assay of hydroxyproline that atrial fibrosis had developed. The absence of dystrophin in mdx mice was accompanied by an overall reduction in syntrophin and a lower NOS1 protein content in the skeletal muscle and in the left atrial and ventricular myocardium, with the latter occurring alongside reduced Nos1 transcript levels (exons 1-2 by quantitative polymerase chain reaction) and an increase in NOS1 polyubiquitination [assessed using tandem polyubiquitination pulldowns; P < 0.05 vs. wild type (WT)]. Neither the up-regulation of miR-31 nor the substantial reduction in NOS activity observed in the skeletal muscle was present in the atrial tissue of mdx mice. At difference with the skeletal muscle, the mdx atrial myocardium showed a reduction in the constitutive NOS inhibitor, caveolin-1, coupled with an increase in NOS3 serine1177 phosphorylation, in the absence of differences in the protein content of other NOS isoforms or in the relative expression NOS1 splice variants. In line with these findings, transoesophageal atrial burst pacing revealed no difference in AF susceptibility between mdx mice and their WT littermates.

CONCLUSION

Dystrophin depletion is not associated with atrial miR-31 up-regulation, reduced NOS activity, or increased AF susceptibility in the mdx mouse. Compared with the skeletal muscle, the milder atrial biochemical phenotype may explain why patients with DMD do not exhibit a higher prevalence of atrial arrhythmias despite a reduction in NOS1 content.

Protein phosphatase 4 mediates palmitic acid-induced endothelial dysfunction by decreasing eNOS phosphorylation at serine 633 in HUVECs

Plasma saturated free fatty acid (FFA)-induced endothelial dysfunction (ED) contributes to the pathogenesis of atherosclerosis and cardiovascular diseases. However, the mechanism underlying saturated FFA-induced ED remains unclear. This study demonstrated that palmitic acid (PA) induced ED by activating the NADPH oxidase (NOX)/ROS signaling pathway to activate protein phosphatase 4 (PP4) and protein phosphatase 2A (PP2A), thereby reducing endothelial nitric oxide synthase (eNOS) phosphorylation at Ser633 and Ser1177, respectively. Okadaic acid (OA) and fostriecin (FST), which are inhibitors of PP2A, inhibited the PA-induced decreases in eNOS phosphorylation at Ser633 and Ser1177. The antioxidants N-acetylcysteine (NAC) and apocynin (APO) or knockdown of gp91phox or p67phox (NOX subunits) restored PA-mediated downregulation of PP4R2 protein expression and eNOS Ser633 phosphorylation. Knockdown of the PP4 catalytic subunit (PP4c) specifically increased eNOS Ser633 phosphorylation, while silencing the PP2A catalytic subunit (PP2Ac) restored only eNOS Ser1177 phosphorylation. Furthermore, PA dramatically decreased the protein expression of the PP4 regulatory subunit R2 (PP4R2) but not the other regulatory subunits. PP4R2 overexpression increased eNOS Ser633 phosphorylation, nitric oxide (NO) production, cell migration and tube formation but did not change eNOS Ser1177 phosphorylation levels. Coimmunoprecipitation (Co-IP) suggested that PP4R2 and PP4c interacted with the PP4R3α and eNOS proteins. In summary, PA decreases PP4R2 protein expression through the Nox/ROS pathway to activate PP4, which contributes to ED by dephosphorylating eNOS at Ser633. The results of this study suggest that PP4 is a novel therapeutic target for ED and ED-associated vascular diseases.

Environmental dose of 16 priority-controlled PAHs induce endothelial dysfunction: An in vivo and in vitro study

Polycyclic aromatic hydrocarbons (PAHs) exposure is related to the occurrence of cardiovascular diseases (CVDs). Endothelial dysfunction is considered an initial event of CVDs. To confirm the relationship of PAHs exposure with endothelial dysfunction, 8-week-old male SD rats and primary human umbilical vein endothelial cells (HUVECs) were co-treated with environmental doses of 16 priority-controlled PAHs for 90 d and 48 h, respectively. Results showed that 10× PAHs exposure remarkably raised tumor necrosis factor-α and malonaldehyde levels in rat serum (p < 0.05), but had no effects on interleukin-8 levels and superoxide dismutase activity. The expressions of SIRT1 in HUVECs and rat aorta were attenuated after PAHs treatment. Interestingly, PAHs exposure did not activate the expression of total endothelial nitric oxide synthase (eNOS), but 10× PAHs exposure significantly elevated the expression of phosphorylated eNOS (Ser1177) in HUVECs and repressed it in aortas, accompanied with raised nitrite level both in serum and HUVECs by 48.50-253.70 %. PAHs exposure also led to the augment of endothelin-1 (ET-1) levels by 19.76-38.54 %, angiotensin (Ang II) levels by 20.09-39.69 % in HUVECs, but had no effects on ET-1 and Ang II levels in serum. Additionally, PAHs exposure improved endocan levels both in HUVECs and serum by 305.05-620.48 % and stimulated the THP-1 cells adhered to HUVECs (p < 0.05). After PAHs treatment, the smooth muscle alignment was disordered and the vascular smooth muscle locally proliferated in rat aorta. Notably, the systolic blood pressure of rats exposed to 10× PAHs increased significantly compared with the control ones (131.28 ± 5.20 vs 116.75 ± 5.33 mmHg). In summary, environmental chronic PAHs exposure may result in endothelial dysfunction in SD rats and primary HUVECs. Our research can confirm the cardiovascular damage caused by chronic exposure to PAHs and provide ideas for the prevention or intervention of CVDs affected by environmental factors.

Intrinsic endothelial hyperresponsiveness to inflammatory mediators drives acute episodes in models of Clarkson disease

Clarkson disease, or monoclonal gammopathy-associated idiopathic systemic capillary leak syndrome (ISCLS), is a rare, relapsing-remitting disorder featuring the abrupt extravasation of fluids and proteins into peripheral tissues, which in turn leads to hypotensive shock, severe hemoconcentration, and hypoalbuminemia. The specific leakage factor(s) and pathways in ISCLS are unknown, and there is no effective treatment for acute flares. Here, we characterize an autonomous vascular endothelial defect in ISCLS that was recapitulated in patient-derived endothelial cells (ECs) in culture and in a mouse model of disease. ISCLS-derived ECs were functionally hyperresponsive to permeability-inducing factors like VEGF and histamine, in part due to increased endothelial nitric oxide synthase (eNOS) activity. eNOS blockade by administration of N(γ)-nitro-l-arginine methyl ester (l-NAME) ameliorated vascular leakage in an SJL/J mouse model of ISCLS induced by histamine or VEGF challenge. eNOS mislocalization and decreased protein phosphatase 2A (PP2A) expression may contribute to eNOS hyperactivation in ISCLS-derived ECs. Our findings provide mechanistic insights into microvascular barrier dysfunction in ISCLS and highlight a potential therapeutic approach.

Shenfu injection: a review of pharmacological effects on cardiovascular diseases

Shenfu injection (SFI), composed of ginseng and aconite, is a Chinese patent developed from the classic traditional prescription Shenfu Decoction created more than 700 years ago. SFI has been widely used in China for over 30 years for treating cardiovascular diseases. The main components in it include ginsenosides and aconitum alkaloids. In recent years, the role of SFI in the treatment of cardiovascular diseases has attracted much attention. The pharmacological effects and therapeutic applications of SFI in cardiovascular diseases are summarized here, highlighting pharmacological features and potential mechanisms developments, confirming that SFI can play a role in multiple ways and is a promising drug for treating cardiovascular diseases.

Tsantan Sumtang, a traditional Tibetan medicine, protects pulmonary vascular endothelial function of hypoxia-induced pulmonary hypertension rats through AKT/eNOS signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Tsantan Sumtang (TS), originated from the Four Tantras, is an empirical Tibetan medicine prescription, which has been widely used for treating cardiovascular diseases in the clinic in Qinghai Province of China. Our previous studies found that TS alleviated hypoxia-induced pulmonary hypertension (HPH) in rats. However, the effect and bioactive fractions of TS on hypoxia-injured pulmonary vascular endothelium are unknown.

AIM OF THE STUDY

To investigate the effect, bioactive fractions and pharmacological mechanism of TS on hypoxia-injured pulmonary vascular endothelium in vivo and in vitro.

MATERIALS AND METHODS

In vivo studies, HPH animal model was established, and TS was administrated for four weeks. Then, hemodynamic indexes, ex vivo pulmonary artery perfusion experiment, morphological characteristics, nitric oxide (NO) production, and the protein expression of protein kinase B (AKT)/endothelial nitric oxide synthase (eNOS) and AMP-activated protein kinase (AMPK)/eNOS signaling were determined. In vitro studies, 1% O2-induced pulmonary artery endothelial cells (PAECs) injury model was applied for screening bioactive fractions of TS by cell proliferation assay and NO production measurement. The associated proteins of AKT/eNOS signaling were further measured to elucidate underlying mechanism of bioactive fraction of TS via using phosphatidylinositol-3 kinase (PI3K) inhibitor LY294002. Ultra-high performance liquid chromatography with hybrid quadrupole-orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS) was used to reveal the chemical profile of bioactive fraction of TS.

RESULTS

TS showed protective effect on the integrity of distal pulmonary arterial endothelium in HPH rats. Tsantan Sumtang dilated pulmonary arterial rings in HPH rats. TS enhanced NO bioavailability in lung tissue via regulating AKT/eNOS signaling. Furthermore, in the cellular level, cell viability as well as NO content of hypoxia-injured PAECs were elevated by fraction 17 of water extract of TS (WTS), through activating the AKT/eNOS signaling. Ellagic acid could be one of compositions in fraction 17 of WTS to produce NO in hypoxia-injured PAECs.

CONCLUSION

TS restored pulmonary arterial endothelial function in HPH rats. The bioactive fraction 17 was screened, which protected hypoxia-injured PAECs via upregulating AKT/eNOS signaling.

Protective Roles and Therapeutic Effects of Gallic Acid in the Treatment of Cardiovascular Diseases: Current Trends and Future Directions

Cardiovascular diseases (CVDs) are serious life-threatening illnesses and significant problematic issues for public health having a heavy economic burden on all society worldwide. The high incidence of these diseases as well as high mortality rates make them the leading causes of death and disability. Therefore, finding novel and more effective therapeutic methods is urgently required. Gallic acid, an herbal medicine with numerous biological properties, has been utilized in the treatment of various diseases for thousands of years. It has been demonstrated that gallic acid possesses pharmacological potential in regulating several molecular and cellular processes such as apoptosis and autophagy. Moreover, gallic acid has been investigated in the treatment of CVDs both in vivo and in vitro. Herein, we aimed to review the available evidence on the therapeutic application of gallic acid for CVDs including myocardial ischemia-reperfusion injury and infarction, drug-induced cardiotoxicity, hypertension, cardiac fibrosis, and heart failure, with a focus on underlying mechanisms.

Harnessing Passive Pulsatile Shear Stress for Alzheimer's Disease Prevention and Intervention

 Alzheimer's disease (AD) affects more than 40 million people worldwide and is the leading cause of dementia. This disease is a challenge for both patients and caregivers and puts a significant strain on the global healthcare system. To address this issue, the Lancet Commission recommends focusing on reducing modifiable lifestyle risk factors such as hypertension, diabetes, and physical inactivity. Passive pulsatile shear stress (PPSS) interventions, which use devices like whole-body periodic acceleration, periodic acceleration along the Z-axis (pGz), and the Jogging Device, have shown significant systemic and cellular effects in preclinical and clinical models which address these modifiable risks factors. Based on this, we propose that PPSS could be a potential non-pharmacological and non-invasive preventive or therapeutic strategy for AD. We perform a comprehensive review of the biological basis based on all publications of PPSS using these devices and demonstrate their effects on the various aspects of AD. We draw from this comprehensive analysis to support our hypothesis. We then delve into the possible application of PPSS as an innovative intervention. We discuss how PPSS holds promise in ameliorating hypertension and diabetes while mitigating physical inactivity, potentially offering a holistic approach to AD prevention and management.

Endothelial nitric oxide synthase (eNOS) S1176 phosphorylation status governs atherosclerotic lesion formation

Objective

We have previously demonstrated the in vivo importance of the Akt-eNOS substrate-kinase relationship, as defective postnatal angiogenesis characteristic of global Akt1-null mice is rescued when bred to 'gain-of-function' eNOS S1176D mutant mice. While multiple studies support the vascular protective role of endothelial NO generation, the causal role of Akt1-dependent eNOS S1176 phosphorylation during atherosclerotic plaque formation is not yet clear.

Approach and results

We herein bred congenic 'loss-of-function' eNOS S1176A and 'gain-of-function' eNOS S1176D mutant mice to the exacerbated atherogenic Akt1-/-; ApoE-/- double knockout mice to definitively test the importance of Akt-mediated eNOS S1176 phosphorylation during atherogenesis. We find that a single amino acid substitution at the eNOS S1176 phosphorylation site yields divergent effects on atherosclerotic plaque formation, as an eNOS phospho-mimic aspartate (D) substitution at S1176 leads to favorable lipid profiles and decreased indices of atherosclerosis, even when on a proatherogenic Akt1 global deletion background. Conversely, mice harboring an unphosphorylatable mutation to alanine (S1176A) result in increased plasma lipids, increased lesion formation and cellular apoptosis, phenocopying the physiological consequence of eNOS deletion and/or impaired enzyme function. Furthermore, gene expression analyses of whole aortas indicate a combinatorial detriment from NO deficiency and Western Diet challenge, as 'loss-of-function' eNOS S1176A mice on a Western Diet present a unique expression pattern indicative of augmented T-cell activity when compared to eNOS S1176D mice.

Conclusions

By using genetic epistasis approaches, we conclusively demonstrate that Akt-mediated eNOS S1176 phosphorylation and subsequent eNOS activation remains to be the most physiologically relevant method of NO production to promote athero-protective effects.

Should the non-canonical pathway of nitric oxide generation be targeted in hypertensive pregnancies?

Hypertension in pregnancy is prevalent, affecting around 10% of pregnancies worldwide, and significantly increases the risk of adverse outcomes for both mothers and their babies. Current treatment strategies for pregnant women with hypertension are limited, and new approaches for the management of hypertension in pregnancy are urgently needed. Substantial evidence from non-pregnant subjects has demonstrated the potential for dietary nitrate supplementation to increase nitric oxide (NO) bioavailability and lower blood pressure, following bioactivation via the non-canonical NO pathway. Emerging data suggest this approach may also be of benefit in pregnant women, although studies are limited. This review aims to summarise the current evidence from preclinical and clinical studies of nitrate supplementation in pregnancy, drawing on data from non-pregnant populations where appropriate and highlighting key gaps in knowledge that remain to be addressed in future trials.

Association between Periodontal Disease and Arteriosclerosis-Related Diseases

Periodontitis, a major inflammatory disease of the oral cavity that can cause low-grade systemic inflammation, has been suggested to influence the development of comorbidities. Multiple systemic inflammatory mechanisms are common in the development of periodontal disease and atherosclerosis. Observational studies conducted worldwide have reported that periodontal disease may independently influence the progression of atherosclerotic disease. However, there is still insufficient evidence to demonstrate the causal relationship. This review describes the association between periodontal disease and arteriosclerosis-related diseases with the latest findings.

Impact of aging on vascular ion channels: perspectives and knowledge gaps across major organ systems

Individuals aged ≥65 yr will comprise ∼20% of the global population by 2030. Cardiovascular disease remains the leading cause of death in the world with age-related endothelial "dysfunction" as a key risk factor. As an organ in and of itself, vascular endothelium courses throughout the mammalian body to coordinate blood flow to all other organs and tissues (e.g., brain, heart, lung, skeletal muscle, gut, kidney, skin) in accord with metabolic demand. In turn, emerging evidence demonstrates that vascular aging and its comorbidities (e.g., neurodegeneration, diabetes, hypertension, kidney disease, heart failure, and cancer) are "channelopathies" in large part. With an emphasis on distinct functional traits and common arrangements across major organs systems, the present literature review encompasses regulation of vascular ion channels that underlie blood flow control throughout the body. The regulation of myoendothelial coupling and local versus conducted signaling are discussed with new perspectives for aging and the development of chronic diseases. Although equipped with an awareness of knowledge gaps in the vascular aging field, a section has been included to encompass general feasibility, role of biological sex, and additional conceptual and experimental considerations (e.g., cell regression and proliferation, gene profile analyses). The ultimate goal is for the reader to see and understand major points of deterioration in vascular function while gaining the ability to think of potential mechanistic and therapeutic strategies to sustain organ perfusion and whole body health with aging.

Influences of lysine-specific demethylase 1 inhibitors on NO synthase-Kruppel-like factor pathways in human endothelial cells in vitro and zebrafish (Danio rerio) larvae in vivo

Lysine-specific demethylase 1 (LSD1) inhibitors are being developed for cancer therapy, but their bioeffects on vasculatures are not clear. In this study, we compared the influences of ORY-1001 (an LSD1 inhibitor being advanced into clinical trials) and 199 (a novel LSD1 inhibitor recently developed by us) to human umbilical vein endothelial cells (HUVECs) in vitro and further verified the bioeffects of ORY-1001 to zebrafish (Danio rerio) larvae in vivo. The results showed that up to 10 μM ORY-1001 or 199 did not significantly affect the cellular viability of HUVECs but substantially reduced the release of inflammatory interleukin-8 (IL-8) and IL-6. The signaling molecule in vasculatures, NO, was also increased in HUVECs. As the mechanism, the protein levels of endothelial NO synthase (eNOS) or p-eNOS, and their regulators Kruppel-like factor 2 (KLF2) or KLF4, were also increased after drug treatment. In vivo, 24 h treatment with up to 100 nM ORY-1001 reduced blood speed without changing morphologies or locomotor activities in zebrafish larvae. ORY-1001 treatment reduced the expression of il8 but promoted the expression of klf2a and nos in the zebrafish model. These data show that LSD1 inhibitors were not toxic but capable to inhibit inflammatory responses and affect the function of blood vessels through the up-regulation of the NOS-KLF pathway.

Endothelial cell dysfunction in cardiac disease: driver or consequence?

The vascular endothelium is a multifunctional cellular system which directly influences blood components and cells within the vessel wall in a given tissue. Importantly, this cellular interface undergoes critical phenotypic changes in response to various biochemical and hemodynamic stimuli, driving several developmental and pathophysiological processes. Multiple studies have indicated a central role of the endothelium in the initiation, progression, and clinical outcomes of cardiac disease. In this review we synthesize the current understanding of endothelial function and dysfunction as mediators of the cardiomyocyte phenotype in the setting of distinct cardiac pathologies; outline existing in vivo and in vitro models where key features of endothelial cell dysfunction can be recapitulated; and discuss future directions for development of endothelium-targeted therapeutics for cardiac diseases with limited existing treatment options.

The role of BRG1 in epigenetic regulation of cardiovascular diseases

Cardiovascular diseases have been closely linked to abnormal epigenetic regulation. In the context of epigenetic regulation, BRG1, a pivotal SWI/SNF chromatin remodeling enzyme, emerges as a key epigenetic regulator with significant impact on the development and progression of cardiovascular disorders. From the perspective of epigenetic regulation of cardiovascular diseases, BRG1 emerges as a pivotal SWI/SNF chromatin remodeling enzyme, functioning as a key epigenetic regulator. It exerts substantial influence on the development and progression of cardiovascular disorders by exerting precise control over gene expression and protein levels. Therefore, a comprehensive understanding of BRG1's epigenetic regulatory role in cardiovascular disease is essential for unraveling its underlying pathophysiological mechanisms. This paper summarizes and discusses the function of BRG1 in the epigenetic regulation of cardiovascular diseases.

Modulation of the nitric oxide/cGMP pathway in cardiac contraction and relaxation: Potential role in heart failure treatment

Evidence exists that heart failure (HF) has an overall impact of 1-2 % in the global population being often associated with comorbidities that contribute to increased disease prevalence, hospitalization, and mortality. Recent advances in pharmacological approaches have significantly improved clinical outcomes for patients with vascular injury and HF. Nevertheless, there remains an unmet need to clarify the crucial role of nitric oxide/cyclic guanosine 3',5'-monophosphate (NO/cGMP) signalling in cardiac contraction and relaxation, to better identify the key mechanisms involved in the pathophysiology of myocardial dysfunction both with reduced (HFrEF) as well as preserved ejection fraction (HFpEF). Indeed, NO signalling plays a crucial role in cardiovascular homeostasis and its dysregulation induces a significant increase in oxidative and nitrosative stress, producing anatomical and physiological cardiac alterations that can lead to heart failure. The present review aims to examine the molecular mechanisms involved in the bioavailability of NO and its modulation of downstream pathways. In particular, we focus on the main therapeutic targets and emphasize the recent evidence of preclinical and clinical studies, describing the different emerging therapeutic strategies developed to counteract NO impaired signalling and cardiovascular disease (CVD) development.

The severity of NEC is ameliorated by prostaglandin E2 through regulating intestinal microcirculation

Prostaglandin E2 (PGE2) is implicated in intestinal inflammation and intestinal blood flow regulation with a paradoxical effect on the pathogenesis of necrotizing enterocolitis (NEC), which is not yet well understood. In the current study, we found that PGE2, EP4, and COX-2 varied at different distances from the most damaged area in the terminal ileum obtained from human infants with NEC. PGE2 administration alleviated the phenotype of experimental NEC and the intestinal microvascular features in experimental NEC, but this phenomenon was inhibited by eNOS depletion, suggesting that PGE2 promoted intestinal microcirculatory perfusion through eNOS. Furthermore, PGE2 administration increased the VEGF content in MIMECs under TNFα stress and promoted MIMEC proliferation. This response to PGE2 was involved in eNOS phosphorylation and nitric oxide (NO) production and was blocked by the EP4 antagonist in vitro, suggesting that targeting the PGE2-EP4-eNOS axis might be a potential clinical and therapeutic strategy for NEC treatment. The study is reported in accordance with ARRIVE guidelines ( https://arriveguidelines.org ).

Perivascular Adipose Tissue Oxidative Stress in Obesity

Perivascular adipose tissue (PVAT) adheres to most systemic blood vessels in the body. Healthy PVAT exerts anticontractile effects on blood vessels and further protects against cardiovascular and metabolic diseases. Healthy PVAT regulates vascular homeostasis via secreting an array of adipokine, hormones, and growth factors. Normally, homeostatic reactive oxygen species (ROS) in PVAT act as secondary messengers in various signalling pathways and contribute to vascular tone regulation. Excessive ROS are eliminated by the antioxidant defence system in PVAT. Oxidative stress occurs when the production of ROS exceeds the endogenous antioxidant defence, leading to a redox imbalance. Oxidative stress is a pivotal pathophysiological process in cardiovascular and metabolic complications. In obesity, PVAT becomes dysfunctional and exerts detrimental effects on the blood vessels. Therefore, redox balance in PVAT emerges as a potential pathophysiological mechanism underlying obesity-induced cardiovascular diseases. In this review, we summarise new findings describing different ROS, the major sources of ROS and antioxidant defence in PVAT, as well as potential pharmacological intervention of PVAT oxidative stress in obesity.

Incretins-Based Therapies and Their Cardiovascular Effects: New Game-Changers for the Management of Patients with Diabetes and Cardiovascular Disease

Atherosclerosis is the leading cause of death worldwide, especially in patients with type 2 diabetes mellitus (T2D). GLP-1 receptor agonists and DPP-4 inhibitors were demonstrated to play a markedly protective role for the cardiovascular system beyond their glycemic control. Several cardiovascular outcome trials (CVOT) reported the association between using these agents and a significant reduction in cardiovascular events in patients with T2D and a high cardiovascular risk profile. Moreover, recent evidence highlights a favorable benefit/risk profile in myocardial infarction and percutaneous coronary revascularization settings. These clinical effects result from their actions on multiple molecular mechanisms involving the immune system, platelets, and endothelial and vascular smooth muscle cells. This comprehensive review specifically concentrates on these cellular and molecular processes mediating the cardiovascular effects of incretins-like molecules, aiming to improve clinicians' knowledge and stimulate a more extensive use of these drugs in clinical practice as helpful cardiovascular preventive strategies.

Reelin through the years: From brain development to inflammation

Reelin was originally identified as a regulator of neuronal migration and synaptic function, but its non-neuronal functions have received far less attention. Reelin participates in organ development and physiological functions in various tissues, but it is also dysregulated in some diseases. In the cardiovascular system, Reelin is abundant in the blood, where it contributes to platelet adhesion and coagulation, as well as vascular adhesion and permeability of leukocytes. It is a pro-inflammatory and pro-thrombotic factor with important implications for autoinflammatory and autoimmune diseases such as multiple sclerosis, Alzheimer's disease, arthritis, atherosclerosis, or cancer. Mechanistically, Reelin is a large secreted glycoprotein that binds to several membrane receptors, including ApoER2, VLDLR, integrins, and ephrins. Reelin signaling depends on the cell type but mostly involves phosphorylation of NF-κB, PI3K, AKT, or JAK/STAT. This review focuses on non-neuronal functions and the therapeutic potential of Reelin, while highlighting secretion, signaling, and functional similarities between cell types.

Serine/Threonine Protein Phosphatases 1 and 2A in Lung Endothelial Barrier Regulation

Vascular barrier dysfunction is characterized by increased permeability and inflammation of endothelial cells (ECs), which are prominent features of acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and sepsis, and a major complication of the SARS-CoV-2 infection and COVID-19. Functional impairment of the EC barrier and accompanying inflammation arises due to microbial toxins and from white blood cells of the lung as part of a defensive action against pathogens, ischemia-reperfusion or blood product transfusions, and aspiration syndromes-based injury. A loss of barrier function results in the excessive movement of fluid and macromolecules from the vasculature into the interstitium and alveolae resulting in pulmonary edema and collapse of the architecture and function of the lungs, and eventually culminates in respiratory failure. Therefore, EC barrier integrity, which is heavily dependent on cytoskeletal elements (mainly actin filaments, microtubules (MTs), cell-matrix focal adhesions, and intercellular junctions) to maintain cellular contacts, is a critical requirement for the preservation of lung function. EC cytoskeletal remodeling is regulated, at least in part, by Ser/Thr phosphorylation/dephosphorylation of key cytoskeletal proteins. While a large body of literature describes the role of phosphorylation of cytoskeletal proteins on Ser/Thr residues in the context of EC barrier regulation, the role of Ser/Thr dephosphorylation catalyzed by Ser/Thr protein phosphatases (PPases) in EC barrier regulation is less documented. Ser/Thr PPases have been proposed to act as a counter-regulatory mechanism that preserves the EC barrier and opposes EC contraction. Despite the importance of PPases, our knowledge of the catalytic and regulatory subunits involved, as well as their cellular targets, is limited and under-appreciated. Therefore, the goal of this review is to discuss the role of Ser/Thr PPases in the regulation of lung EC cytoskeleton and permeability with special emphasis on the role of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) as major mammalian Ser/Thr PPases. Importantly, we integrate the role of PPases with the structural dynamics of the cytoskeleton and signaling cascades that regulate endothelial cell permeability and inflammation.

Growth State-Dependent Activation of eNOS in Response to DHA: Involvement of p38 MAPK

Our laboratory previously reported that docosahexaenoic acid (DHA) differentially activates p38 mitogen-activated protein kinase (MAPK) in growing and quiescent human endothelial cells, which represent the dysfunctional and healthy states in vivo, respectively. Since endothelial nitric oxide synthase (eNOS) activity differs between healthy and dysfunctional endothelial cells, and p38 MAPK reportedly regulates both the activity and expression of eNOS, we hypothesized that the beneficial actions of DHA on endothelial cells are due to eNOS activation by p38 MAPK. The contribution of mitogen- and stress-activated protein kinase (MSK), a p38 MAPK substrate, was also investigated. Growing and quiescent EA.hy926 cells, prepared on Matrigel^®-coated plates, were incubated with inhibitors of p38MAPK or MSK before adding DHA. eNOS phosphorylation and levels were quantified by Western blotting. Treatment with 20 µM DHA activated eNOS in both growth states whereas 125 µM DHA suppressed eNOS activation in growing cells. Quiescent cells had higher basal levels of eNOS than growing cells, while 125 µM DHA decreased eNOS levels in both growth states. p38 MAPK inhibition enhanced eNOS activation in quiescent cells but suppressed it in growing cells. Interestingly, 125 µM DHA counteracted these effects of p38 MAPK inhibition in both growth states. MSK was required for eNOS activation in both growth states, but it only mediated eNOS activation by DHA in quiescent cells. MSK thus affects eNOS via a pathway independent of p38MAPK. Quiescent cells were also more resistant to the apoptosis-inducing effect of 125 µM DHA compared to growing cells. The growth state-dependent regulation of p38MAPK and eNOS by DHA provides novel insight into the molecular mechanisms by which DHA influences endothelial cell function.

Fucoidan and topography modification improved in situ endothelialization on acellular synthetic vascular grafts

Thrombogenesis remains the primary failure of synthetic vascular grafts. Endothelial coverage is crucial to provide an antithrombogenic surface. However, most synthetic materials do not support cell adhesion, and transanastomotic endothelial migration is limited. Here, a surface modification strategy using fucoidan and topography was developed to enable fast in situ endothelialization of polyvinyl alcohol, which is not endothelial cell-adhesive. Among three different immobilization approaches compared, conjugation of aminated-fucoidan promoted endothelial monolayer formation while minimizing thrombogenicity in both in vitro platelet rich plasma testing and ex vivo non-human primate shunt assay. Screening of six topographical patterns showed that 2 μm gratings increased endothelial cell migration without inducing inflammation responses of endothelial cells. Mechanistic studies demonstrated that fucoidan could attract fibronectin, enabling integrin binding and focal adhesion formation and activating focal adhesion kinase (FAK) signaling, and 2 μm gratings further enhanced FAK-mediated cell migration. In a clinically relevant rabbit carotid artery end-to-side anastomosis model, 60% in situ endothelialization was observed throughout the entire lumen of 1.7 mm inner diameter modified grafts, compared to 0% of unmodified graft, and the four-week graft patency also increased. This work presents a promising strategy to stimulate in situ endothelialization on synthetic materials for improving long-term performance.

Gene Polymorphism and Recurrent Atrial Fibrillation after Catheter Ablation: A Comprehensive Review

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias, but its pathogenesis is still poorly understood. Catheter ablation is one of the most effective treatments for AF, but recurrence after ablation remains a challenge. There has been much research into the association of AF recurrence with several factors, including genetics. Over the past decade or so, significant advances have been made in the genetic architecture of atrial fibrillation. Genome-wide association studies (GWAS) have identified over 100 loci for genetic variants associated with atrial fibrillation. However, there is relatively little information on the systematic assessment of the genes related to AF recurrence after ablation. In this review article, we highlight the value of genetic polymorphisms in atrial fibrillation recurrence after catheter ablation and their potential mechanisms in the recurrence process to enhance our understanding of atrial fibrillation recurrence and contribute to individualized treatment strategies for patients with AF.

BMPER Improves Vascular Remodeling and the Contractile Vascular SMC Phenotype

Dedifferentiated vascular smooth muscle cells (vSMCs) play an essential role in neointima formation, and we now aim to investigate the role of the bone morphogenetic protein (BMP) modulator BMPER (BMP endothelial cell precursor-derived regulator) in neointima formation. To assess BMPER expression in arterial restenosis, we used a mouse carotid ligation model with perivascular cuff placement. Overall BMPER expression after vessel injury was increased; however, expression in the tunica media was decreased compared to untreated control. Consistently, BMPER expression was decreased in proliferative, dedifferentiated vSMC in vitro. C57BL/6_Bmper+/- mice displayed increased neointima formation 21 days after carotid ligation and enhanced expression of Col3A1, MMP2, and MMP9. Silencing of BMPER increased the proliferation and migration capacity of primary vSMCs, as well as reduced contractibility and expression of contractile markers, whereas stimulation with recombinant BMPER protein had the opposite effect. Mechanistically, we showed that BMPER binds insulin-like growth factor-binding protein 4 (IGFBP4), resulting in the modulation of IGF signaling. Furthermore, perivascular application of recombinant BMPER protein prevented neointima formation and ECM deposition in C57BL/6N mice after carotid ligation. Our data demonstrate that BMPER stimulation causes a contractile vSMC phenotype and suggest that BMPER has the potential for a future therapeutic agent in occlusive cardiovascular diseases.

Piezoelectric Bioactive Glasses Composite Promotes Angiogenesis by the Synergistic Effect of Wireless Electrical Stimulation and Active Ions

Insufficient angiogenesis frequently occurs after the implantation of orthopedic materials, which greatly increases the risk of bone defect reconstruction failure. Therefore, the development of bone implant with improved angiogenic properties is of great importance. Mimicking the extracellular matrix clues provides a more direct and effective strategy to modulate angiogenesis. Herein, inspired by the bioelectrical characteristics of the bone microenvironment, a piezoelectric bioactive glasses composite (P-KNN/BG) based on the incorporation of polarized potassium sodium niobate is constructed, which could effectively promote angiogenesis. It is found that P-KNN/BG has exceptional wireless electrical stimulation performance and sustained active ions release. In vitro cell experiments reveal that P-KNN/BG enhances endothelial cell adhesion, migration, and differentiation via activating the eNOS/NO signaling pathway, which might be contributed to cell membrane hyperpolarization induced by wireless electrical stimulation increase the influx of active ions into the cells. In vivo chick chorioallantoic membrane experiment demonstrates that P-KNN/BG shows excellent pro-angiogenic capacity and biocompatibility. This work broadens the current understanding of bioactive materials with bionic electrical properties, which brings new insights into the clinical treatment of bone defect repair.

Utilizing the Off-Target Effects of T1R3 Antagonist Lactisole to Enhance Nitric Oxide Production in Basal Airway Epithelial Cells

Human airway sweet (T1R2 + T1R3), umami (T1R1 + T1R3), and bitter taste receptors (T2Rs) are critical components of the innate immune system, acting as sensors to monitor pathogenic growth. T2Rs detect bacterial products or bitter compounds to drive nitric oxide (NO) production in both healthy and diseased epithelial cell models. The NO enhances ciliary beating and also directly kills pathogens. Both sweet and umami receptors have been characterized to repress bitter taste receptor signaling in healthy and disease models. We hypothesized that the sweet/umami T1R3 antagonist lactisole may be used to alleviate bitter taste receptor repression in airway basal epithelial cells and enhance NO production. Here, we show that lactisole activates cAMP generation, though this occurs through a pathway independent of T1R3. This cAMP most likely signals through EPAC to increase ER Ca²⁺ efflux. Stimulation with denatonium benzoate, a bitter taste receptor agonist which activates largely nuclear and mitochondrial Ca²⁺ responses, resulted in a dramatically increased cytosolic Ca²⁺ response in cells treated with lactisole. This cytosolic Ca²⁺ signaling activated NO production in the presence of lactisole. Thus, lactisole may be useful coupled with bitter compounds as a therapeutic nasal rinse or spray to enhance beneficial antibacterial NO production in patients suffering from chronic inflammatory diseases such as chronic rhinosinusitis.

The role of arginine and endothelial nitric oxide synthase in the pathogenesis of Covid-19 complicated by metabolic syndrome

This literature review presents the role of endothelial nitric oxide synthase (eNOS) and nitric oxide (NO), as well as arginine, the enzyme substrate, in the disease of metabolic syndrome and COVID-19 (SARS-CoV-2 virus). Metabolic syndrome is a combination of obesity, insulin resistance, hyperglycemia, dyslipidemia and hypertension. It has been shown that in elderly people, patients with obesity, metabolic syndrome, type 2 diabetes mellitus (DM2), and patients with COVID-19, endothelial dysfunction (ED) and vascular endothelial activation are detected. ED is the main cause of a number of pathological conditions during the development of COVID-19 and earlier in patients with metabolic syndrome, while a sharp drop in the level of nitric oxide (NO) is detected due to a decrease in the expression and activity of eNO synthase and enzyme depletion, which leads to a violation of the integrity of bloodvessels, that is, to vasoconstrictive, inflammatory and thrombotic conditions, followed by ischemia of organs and edema of tissues. It should be noted that metabolic syndrome, DM2, hypertension and obesity, in particular, are age-related diseases, and it is known that blood glucose levels increase with age, which reduces the bioavailability of NO in endothelial cells. Defects in the metabolism of NO cause dysfunction in the pulmonary blood vessels, the level of NO decreases, which leads to impaired lung function and coagulopathy. The review presents possible mechanisms of these disorders associated with ED, the release of eNO synthase, changes in phosphorylation and regulation of enzyme activity, as well as insulin resistance. A modern view of the role of the polymorphism of the eNO synthase gene in the development of these pathologies is presented. To increase the level of endothelial NO, drugs are offered that regulate the bioavailability of NO. These include arginine, agonist NO – minoxidil, steroid hormones, statins, metformin. However, further research and clinical trials are needed to develop treatment strategies that increase NO levels in the endothelium.

Wireless electrical stimulation at the nanoscale interface induces tumor vascular normalization

Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not fully effective and limited by the development of resistance. Herein, inspired by the intervention of endogenous bioelectricity in vessel formation, we propose a wireless electrical stimulation therapeutic strategy, capable of breaking bioelectric homeostasis within cells, to achieve tumor vascular normalization. Polarized barium titanate nanoparticles with high mechano-electrical conversion performance were developed, which could generate pulsed open-circuit voltage under low-intensity pulsed ultrasound. We demonstrated that wireless electrical stimulation significantly inhibited endothelial cell migration and differentiation in vitro. Interestingly, we found that the angiogenesis-related eNOS/NO pathway was inhibited, which could be attributed to the destruction of the intracellular calcium ion gradient by wireless electrical stimulation. In vivo tumor-bearing mouse model indicated that wireless electrical stimulation normalized tumor vasculature by optimizing vascular structure, enhancing blood perfusion, reducing vascular leakage, and restoring local oxygenation. Ultimately, the anti-tumor efficacy of combination treatment was 1.8 times that of the single chemotherapeutic drug doxorubicin group. This work provides a wireless electrical stimulation strategy based on the mechano-electrical conversion performance of piezoelectric nanoparticles, which is expected to achieve safe and effective clinical adjuvant treatment of malignant tumors.

•

Wireless electrical stimulation was proposed for tumor vascular normalization.

•

Polarized ferroelectric nanoparticles were developed for wireless stimulation.

•

Wireless stimulation inhibited endothelial cell migration and differentiation.

•

The intracellular Ca²⁺ gradient and eNOS/NO pathway of cells were disturbed.

•

In vivo vascular normalization and anti-tumor efficacy were significantly enhanced.

The Long-Term Effects of Prenatal Hypoxia on Coronary Artery Function of the Male and Female Offspring

Prenatal hypoxia predisposes the offspring to the development of cardiovascular (CV) dysfunction in adult life. Using a rat model, we assessed the effect of prenatal hypoxia on vasoconstrictive and vasodilative mechanisms in left anterior descending coronary arteries of 4- and 9.5-month-old offspring. Endothelium-dependent relaxation to methylcholine and vasoconstriction responses to endothelin-1 (ET-1) were assessed by wire myography. Prenatal hypoxia impaired endothelium-dependent vasodilation in 4- and 9.5-month-old offspring. Inhibition of nitric oxide (NO) synthase prevented coronary artery relaxation in all groups. Inhibition of prostaglandin H synthase (PGHS) improved relaxation in prenatally hypoxic males and tended to improve vasorelaxation in females, suggesting that impaired vasodilation was mediated via increased PGHS-dependent vasoconstriction. An enhanced contribution of endothelium-dependent hyperpolarization to coronary artery vasodilation was observed in prenatally hypoxic males and females. No changes in endothelial NO synthase (eNOS) and PGHS-1 expressions were observed, while PGHS-2 expression was decreased in only prenatally hypoxic males. At 4 months, ET-1 responses were similar between groups, while ET_B inhibition (with BQ788) tended to decrease ET-1-mediated responses in only prenatally hypoxic females. At 9.5 months, ET-1-mediated responses were decreased in only prenatally hypoxic females. Our data suggest that prenatal hypoxia has long-term similar effects on the mechanisms of impaired endothelium-dependent vasodilation in coronary arteries from adult male and female offspring; however, coronary artery contractile capacity is impaired only in prenatally hypoxic females. Understanding the mechanistic pathways involved in the programming of CV disease may allow for the development of therapeutic interventions.

Curcumin-Added Whey Protein Positively Modulates Skeletal Muscle Inflammation and Oxidative Damage after Exhaustive Exercise

(1) Background: Exhaustive exercise can induce muscle damage. The consumption of nutritional compounds with the ability to positively influence the oxidative balance and an exacerbated inflammatory process has been previously studied. However, little is known about the nutritional value of curcumin (CCM) when mixed with whey protein concentrate (WPC). This study was developed to evaluate the effect of CCM-added WPC on inflammatory and oxidative process control and histopathological consequences in muscle tissue submitted to an exhaustive swimming test (ET). (2) Methods: 48 animals were randomly allocated to six groups (n = 8). An ET was performed 4 weeks after the start of the diet and animals were euthanized 24 h post ET. (3) Results: WPC + CCM and CCM groups reduced IL-6 and increased IL-10 expression in muscle tissue. CCM reduced carbonyl protein after ET compared to standard AIN-93M ET and WPC + CCM ET diets. Higher nitric oxide concentrations were observed in animals that consumed WPC + CCM and CCM. Consumption of WPC + CCM or isolated CCM reduced areas of inflammatory infiltrate and fibrotic tissue in the muscle. (4) Conclusions: WPC + CCM and isolated CCM contribute to the reduction in inflammation and oxidative damage caused by the exhaustive swimming test.

Advances in pathogenesis and treatment of essential hypertension

Hypertension is a significant risk factor for cardiovascular and cerebrovascular diseases and the leading cause of premature death worldwide. However, the pathogenesis of the hypertension, especially essential hypertension, is complex and requires in-depth studies. Recently, new findings about essential hypertension have emerged, and these may provide important theoretical bases and therapeutic tools to break through the existing bottleneck of essential hypertension. In this review, we demonstrated important advances in the different pathogenesis areas of essential hypertension, and highlighted new treatments proposed in these areas, hoping to provide insight for the prevention and treatment of the essential hypertension.

Saluisn-β contributes to endothelial dysfunction in monocrotaline-induced pulmonary arterial hypertensive rats

BACKGROUND

The endothelial dysfunction and the consequent attenuated pulmonary vasodilatation are the major causes of elevated pulmonary arterial resistance and pressure in pulmonary arterial hypertension (PAH). Current study aimed to explore the effects of a TOR2A gene product, salusin-β, on endothelium-dependent vascular relaxation and the progression of PAH in monocrotaline (MCT)-induced PAH rats as well as the relevant signaling pathway.

METHODS

Acetylcholine (ACh)-induced dose-dependent relaxation was used to evaluate the endothelium-dependent vasodilatation function.

RESULTS

The salusin-β level in plasma and pulmonary artery (PA) in MCT-PAH rats were significantly increased, while the ACh-induced endothelium-dependent vasodilatation was attenuated. After salusin-β incubation or overexpression of salusin-β gene, the endothelium-dependent relaxation was further deteriorated, while anti-salusin-β IgG incubation or knockdown of salusin-β improved it in PAH rats. The superoxide anions scavenger NAC or the antioxidant apocynin inhibited the effect of salusin-β, while the SOD inhibitor DETC further enhanced it. The nitric oxide (NO) synthase inhibitor L-NAME almost blocked the effect of anti-salusin-β IgG. Silencing of salusin-β in PAH rats decreased right ventricular (RV) systolic pressure, RV hypertrophy index, NAD(P)H oxidase activity and ROS level, and increased the eNOS activity and NO level of PA. Overexpression of salusin-β played opposite roles.

CONCLUSIONS

The elevated saluisn-β level in PAH rats plays important roles in the reduction of endothelium-dependent vasodilatation and participates in the progression of PAH through stimulating NAD(P)H oxidase-ROS production and inhibiting eNOS-NO release.

Effects of Compound Feed Attractants on Growth Performance, Feed Utilization, Intestinal Histology, Protein Synthesis, and Immune Response of White Shrimp (Litopenaeus Vannamei)

To investigate the effects of compound attractants on the growth performance, feed utilization, intestinal morphology, protein synthesis, and immune response of Litopenaeus vannamei, the following seven diets were formulated: a positive control (P), a negative control (N), and five diets with compound attractants which were labeled as A, B, C, D, and E, each with four of five tested attractants (yeast extract, squid visceral powder, fish soluble, and squid paste, shrimp paste), respectively. Shrimp (0.71 ± 0.00 g) were distributed to seven groups of four replicates and fed for 7 weeks. Results showed that the final body weight, feed intake, specific growth rate, and weight gain of shrimp in the B and D groups were the greatest. Hemolymph total antioxidant capacity of shrimp in the B, D, and E groups reached the highest level. In the hepatopancreas, the activity of total nitric oxide synthase, malondialdehyde content, the expression levels of sod, myd88, eif4e2, and raptor in shrimp fed the B diet were the highest, and the highest levels of dorsal and relish were observed in the C group. In the intestine, intestinal muscle thickness and expression levels of toll and eif2α in the C group were the highest, while the highest expression level of sod and relish occurred in the B group. In summary, the B and E diets promoted the feed intake, growth performance and the antioxidant enzyme activity of L. vannamei. The C diet enhanced the protein synthesis of shrimp. Regression analysis indicated that the WG and FI of shrimp were increased as the dietary inclusion levels of squid paste and shrimp paste increased, while they were decreased as the dietary inclusion levels of yeast extract and fish soluble increased.

The impact of periodontitis on vascular endothelial dysfunction

Periodontitis, an oral inflammatory disease, originates from periodontal microbiota dysbiosis which is associated with the dysregulation of host immunoinflammatory response. This chronic infection is not only harmful to oral health but is also a risk factor for the onset and progress of various vascular diseases, such as hypertension, atherosclerosis, and coronary arterial disease. Vascular endothelial dysfunction is the initial key pathological feature of vascular diseases. Clarifying the association between periodontitis and vascular endothelial dysfunction is undoubtedly a key breakthrough for understanding the potential relationship between periodontitis and vascular diseases. However, there is currently a lack of an updated review of their relationship. Therefore, we aim to focus on the implications of periodontitis in vascular endothelial dysfunction in this review.