Endothelial Cell Function Research Articles

An Endogenous Aryl Hydrocarbon Receptor Ligand Dysregulates Endothelial Functions, Transcriptome, and Phosphoproteome.

We have reported that an endogenous aryl hydrocarbon receptor (AhR) ligand, 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), inhibits functions of human umbilical vein endothelial cells (HUVECs) and induces preeclampsia (PE)-like symptoms in rats. Herein, we tested the hypothesis that ITE impairs endothelial functions via disturbing transcriptome and phosphoproteome in HUVECs. We measured AhR activity in human maternal and umbilical vein sera from PE and normotensive (NT) pregnancies. The serum-induced changes in CYP1A1/B1 mRNA (indexes of AhR activation) in HUVECs were quantified using RT-qPCR. ITE's effects on endothelial proliferation and monolayer integrity in female and male HUVECs were determined. We profiled ITE-induced changes in transcriptome and phosphoproteome in HUVECs using RNA-seq and bottom-up phosphoproteomics, respectively. After 12 hr of treatment, umbilical vein sera from PE increased CYP1A1 mRNA (1.7-fold of NT) HUVECs, which was blocked by CH223191, an AhR antagonist. ITE dose-dependently inhibited endothelial proliferation (76%-87% of control) and time-dependently reduced endothelial integrity with a maximum inhibition (~ 10%) at 40 hr. ITE induced 140 and 80 differentially expressed genes in female and male HUVECs, respectively. ITE altered phosphorylation of 92 and 105 proteins at 4 and 24 hr, respectively, in HUVECs. These ITE-dysregulated genes and phosphoproteins were enriched in biological functions and pathways are relevant to heart, liver, and kidney diseases, vascular functions, and inflammatory responses. Thus, endogenous AhR ligands may impair endothelial functions by disturbing transcriptome and phosphoproteome. These AhR ligand-dysregulated genes and phosphoproteins may be therapeutic and cell sex-specific targets for PE-induced endothelial dysfunction.

Fatty acid binding protein 3 activates endothelial adhesion of circulating monocytes and impairs endothelial angiogenesis.

Vascular inflammation and endothelial dysfunction cause the development of atherosclerotic cardiovascular diseases including coronary artery disease (CAD). While elevated fatty acid binding protein 3 (FABP3) may be associated with the presence of cardiovascular diseases, its mechanistic effects remain unclear. This study aimed to investigate the role of FABP3 in impaired angiogenesis and the development of atherosclerosis in CAD. In total, 1104 patients were enrolled in a clinical observational study and the correlation between serum FABP3 and cardiovascular events were analysed. Another group of CAD patients and non-CAD subjects were enrolled, and their plasma FABP3 concentrations were measured. Primary cultured mononuclear cells endothelial progenitor cells and human coronary artery endothelial cells were used in vitro. Matrigel plug neovascularisation assay and the aortic ring assay were used in wild-type and apolipoprotein E-knockout mice in vivo. Circulating FABP3 was up-regulated in the cardiovascular event-positive group and in the CAD patients. Mononuclear cells from the CAD patients presented increased expression of FABP3. FABP3 enhanced the expression of adhesion molecules, including integrin β2, integrin α4 and PSGL1 in mononuclear cells. FABP3 caused endothelial cell dysfunction through the ERK/p38/STAT1/VEGF signalling pathway. Moreover, oxLDL or TNF-α stimulations impaired endothelial cell function through FABP3-dependent signalling pathways. FABP3 also impaired in vivo angiogenesis. This study elucidates the clinical and pathological impact of FABP3 on atherosclerotic CAD. Future research may be necessary to evaluate whether FABP3 could be a therapeutic target, especially with regard to stable CAD.

Exercise Training After Myocardial Infarction Enhances Endothelial Progenitor Cells Function via NRG-1 Signaling.

Vascular regeneration after myocardial infarction (MI) is essential to improve myocardial ischemia, delay post-infarction ventricular remodeling, and improve the long-term prognosis of MI. Endothelial progenitor cells (EPCs) play important roles in the functional repair and homeostatic maintenance of the vascular endothelium. Exercise training stimulates EPC mobilization and increases the number of circulating EPCs, which has beneficial effects on the restoration of vascular integrity and hemodynamic reconstitution. After post-MI exercise training, cardiac function, the myocardial infarct area, and capillary density in the peri-infarct zone were measured. Bone marrow-derived EPCs were isolated from mice to measure the proliferation, migration, and in vitro angiogenesis of EPCs after myocardial infarction exercise. The expression of NRG-1/ErbB4 signaling factor and related proteins in downstream PI3K/AKT signaling pathway were detected, and the level of autocrine NRG-1 in EPCs was detected. Post-MI resistance training, aerobic exercise training, and combined exercise training increased EPC mobilization and proliferation, migration, and tube-forming capacity, promoted myocardial vascular regeneration, improved cardiac function, and reduced infarct size. Exercise training upregulated NRG-1 expression in EPCs, and NRG-1/ErbB4 signaling activated the downstream PI3K/Akt signaling pathway. Moreover, EPCs may have a positive feedback autocrine loop with NRG-1 to improve the function of EPCs and promote vascular repair and regeneration in mice with MI. Exercise training after MI promotes the function of bone marrow-derived EPCs through NRG-1/ErbB4/PI3K/AKT signaling, thus exerting a role in angiogenesis.

PH-sensitive nano-drug delivery systems dual-target endothelial cells and macrophages for enhanced treatment of atherosclerosis.

Atherosclerosis (AS) is a chronic inflammatory disease characterized by vascular endothelial dysfunction. In the early stage of the disease, endothelial cell injury induces the infiltration of inflammatory macrophages, which secrete large amounts of inflammatory factors, further aggravating endothelial cell dysfunction and exacerbating the disease. Therefore, it is promising for co-targeting endothelial cells and macrophages further regulating the inflammatory microenvironment and endothelial cell function for effective treatment. The current nano-drug delivery system (NDDS) for AS treatment is mainly focused on anti-inflammatory therapy, while ignoring the potential value of suppressing inflammation and simultaneously improving vascular endothelial function. In this study, a pH-responsive dual-targeted NDDS based on plaque microenvironment, BC@CS/cRGD NPs, was prepared by combining baicalin (BC) with chondroitin sulfate (CS) through amidation reaction, and further modified with a targeting group cRGD peptide. In vitro release experiments illustrated a faster release of the nanoparticle at pH 5.0 than at pH 7.4. Meanwhile, in vitro cellular experiments demonstrated its ability to target activated endothelial cells and macrophages. In a mouse model of AS, BC@CS/cRGD NPs accumulated at plaque sites and effectively attenuated the plaque progression. In conclusion, this pH-sensitive BC@CS/cRGD NPs offered a very potential strategy for modulating endothelial dysfunction and inflammatory microenvironment for the treatment of AS.

GDF11 restores the impaired function of EPCs-MA by promoting autophagy: GDF11 ameliorates endothelial progenitor cell aging by promoting autophagy

Abstract Objective Our study aimed to assess the effects of Growth and differentiation factor 11 (GDF11) on the function of endothelial progenitor cells in middle-age individuals (EPCs-MA) isolated from mouse bone marrow and to explore the mechanistic relationship between GDF11 and age-related ALP impairment. Methods Bone marrow-derived EPCs were isolated, culture and GDF11 treatment. In vivo, the mice model of myocardial ischemia (MI) was induced by permanent ligation of the left anterior descending coronary artery (LAD) and mice were randomly divided into MI group and EPCs transplantation group (EPCs-Y, EPCs-MA, EPCs-MA/GDF11). The positive effect of GDF11 treatment of EPCs-MA on MI was verified by echocardiography and the average ratio of fibrotic area to left ventricular (LV) area. In vitro, the effect of GDF11 on ameliorating EPCs aging by promoting autophagy was confirmed by transwell assay, immunofluorescence staining, characterization of EPCs ultrastructure through transmission electron microscope (TEM), lysosome imaging and Western blot. Result Our findings demonstrate that GDF11 enhances the migration capacity of EPCs-MA and improves recovery of impaired cardiac function after myocardial infarction (MI) in mice, with EPCs isolated from young mice (EPCs-Y) as controls. Moreover, GDF11 restored functional phenotypes of EPCs-MA to levels akin to EPCs-Y, promoting the expression of CD31, endogenous NO synthase, and the restoration of von Willebrand factor (vWF) and CDH5 expression patterns, as well as the formation of Weibel-Palade bodies—key organelles for storage and secretion in endothelial cells and EPCs. Furthermore, GDF11 significantly enhanced the autophagic clearance capability of EPCs-MA by promoting ALP. Conclusions Our results suggest that GDF11 ameliorates cardiac function impairment by restoring the activities of EPCs from aging mice through enhanced ALP. These findings suggest that GDF11 may hold therapeutic potential for improving aging-related conditions associated with declined autophagy.

Impact of sodium-glucose cotransporter-2 inhibitors on pulmonary vascular cell function and arterial remodeling.

Sodium-glucose cotransporter-2 (SGLT-2) inhibitors represent a cutting-edge class of oral antidiabetic therapeutics that operate through selective inhibition of glucose reabsorption in proximal renal tubules, consequently augmenting urinary glucose excretion and attenuating blood glucose levels. Extensive clinical investigations have demonstrated their profound cardiovascular efficacy. Parallel basic science research has elucidated the mechanistic pathways through which diverse SGLT-2 inhibitors beneficially modulate pulmonary vascular cells and arterial remodeling. Specifically, these inhibitors exhibit promising potential in enhancing pulmonary vascular endothelial cell function, suppressing pulmonary smooth muscle cell proliferation and migration, reversing pulmonary arterial remodeling, and maintaining hemodynamic equilibrium. This comprehensive review synthesizes current literature to delineate the mechanisms by which SGLT-2 inhibitors enhance pulmonary vascular cell function and reverse pulmonary remodeling, thereby offering novel therapeutic perspectives for pulmonary vascular diseases.

Talin, a Rap1 effector for integrin activation at the plasma membrane, also promotes Rap1 activity by disrupting sequestration of Rap1 by SHANK3.

Talin regulates the adhesion and migration of cells in part by promoting the affinity of integrins for extracellular matrix proteins, a process that in cells such as endothelial cells and platelets requires the direct interaction of talin with both the small GTPase, Rap1-GTP, and the integrin β3 cytoplasmic tail. To study this process in more detail, we employed an optogenetic approach in living, immortalized endothelial cells to be able to regulate talin interaction with the plasma membrane. Previous studies identified talin as the Rap1-GTP effector for β3 integrin activation. Surprisingly, optogenetic recruitment of talin to the plasma membrane also led to the localized activation of Rap1 itself, apparently by talin competing for Rap1-GTP with SHANK3, a protein known to sequester Rap1-GTP and to block integrin activation. Rap1 activation by talin was localized to the cell periphery in suspension cells and within lamellipodia and pseudopodia in cells adherent to fibronectin. Thus, membrane-associated talin can play a dual role in regulating integrin function in endothelial cells: first by releasing Rap1-GTP from its sequestration by SHANK3 and second by serving as the relevant Rap1 effector for integrin activation.

Chloride intracellular channel (CLIC) protein function in S1P-induced Rac1 activation requires membrane localization of the C-terminus, but not thiol-transferase nor ion channel activities.

We have established a novel and evolutionarily-conserved function for chloride intracellular channel proteins (CLICs) in regulating Rho/Rac GTPases downstream of G protein-coupled receptors (GPCRs). Endothelial CLIC1 and CLIC4 are rapidly and transiently re-localized from the cytoplasm to the plasma membrane in response to the GPCR ligand sphingosine-1-phosphate (S1P), and both CLICs are required to activate Rac1 in response to S1P, but how they perform this function remains unknown. Biochemical studies suggest that CLICs act as non-specific ion channels and/or as glutathione-S-transferases, dependent on N-terminal features, in vitro . Here we investigate CLIC functional domains and membrane localization requirements for their function in S1P-mediated Rac1 signaling. Structure-function analyses of CLIC function in endothelial cells demonstrate that CLIC1 and CLIC4-specific functions reside at their C-termini, and that the CLIC4 N-terminus encodes determinants required for S1P-induced re-localization to the plasma membrane but is dispensable for S1P-induced Rac1 activation when the C-terminus is localized to the plasma membrane via a heterologous signal. Our results demonstrate that the postulated ion channel and thiol-transferase activities of CLICs are not required for Rac1 activation and suggests that sequences in the CLIC C-termini are critical for this function. Given the importance of S1P signaling in vascular biology and disease, our work establishes a platform to further our understanding of the membrane-localized proteins required to link GPCR activity to Rho/Rac regulation.

Extracellular vesicle-associated miR-ERIA exerts the anti-angiogenic effect of macrophages in diabetic wound healing.

Many cell types are involved in the regulation of cutaneous wound healing in diabetes. Clarifying the mechanism of cell-cell interactions is important for identifying therapeutic targets for diabetic cutaneous ulcers. The function of vascular endothelial cells in the cutaneous microenvironment is critical, and a decrease in their biological function leads directly to refractory wound healing. In this study, we aimed to study the interactions of macrophages with vascular endothelial cells and elucidate the mechanism of diabetic wound angiogenesis suppression. We found that macrophages polarized to the M1 type, inhibited the migration and tube formation of human umbilical vein endothelial cells (HUVECs) by secreting extracellular vesicles after treatment with advanced glycation end products (AGEs-EVs), and contributed to wound angiogenesis and delayed wound healing in vivo. Mechanistically, we identified a novel miRNA enriched in AGEs-EVs, namely miR-ERIA, that suppress the biological function of HUVECs by targeting helicase with zinc finger 2 (HELZ2), and in vivo experiments showed that miR-ERIA suppression could promote wound angiogenesis and thus accelerate wound healing in diabetes. We found that miR-ERIA regulates diabetic wound angiogenesis by targeting HELZ2, suggesting a potential therapeutic target for diabetic foot ulcers.

Hepatic Abnormal Secretion of Apolipoprotein C3 Promotes Inflammation in Aortic Dissection.

Apolipoprotein C3 (apo C3) is primarily secreted by the liver and is involved in promoting sterile inflammation and organ damage under pathological conditions. Previous studies have shown that apo C3 is abundant in the plasma exosomes of patients with aortic dissection (AD), but its specific role in AD remains unclear. In vivo, adeno-associated virus was used to knock down hepatic apo C3 expression in an AD mouse model to assess the impact of liver-derived apo C3 on the development of AD. Invitro, recombinant apo C3 protein was added to the culture medium of J774A.1 macrophages to evaluate its effect on macrophage polarization and to identify the underlying mechanisms. Additionally, the effect of apo C3 on the function of aortic endothelial and smooth muscle cells was explored. Apo C3 in the aortas of AD mice was found to originate from abnormal hepatic secretion, which enters the bloodstream and subsequently deposits in the aorta. Adeno-associated virus-mediated hepatic apo C3 knockdown significantly reduced AD incidence (P=0.0036), macrophage infiltration (P=0.0004), and collagen deposition in the aorta (P=0.0016). Similarly, inhibiting the apo C3 receptor Toll-like receptor 2 significantly lowered AD incidence (P=0.0352). Invitro, recombinant apo C3 protein promoted M1 polarization and matrix metalloproteinase secretion in macrophages by activating the Toll-like receptor 2/NLR family pyrin domain containing 3 pathway. Additionally, apo C3 increased adhesion molecule expression in endothelial cells and induced inflammation, chemotaxis, and apoptosis in vascular smooth muscle cells. Our findings highlight the role of abnormally secreted hepatic apo C3 in promoting aortic inflammation.

Placental Hypoxia-Induced Ferroptosis Drives Vascular Damage in Preeclampsia.

Iron is an essential micronutrient for cell survival and growth; however, excess of this metal drives ferroptosis. Although maternal iron imbalance and placental hypoxia are independent contributors to the pathogenesis of preeclampsia, a hypertensive disorder of pregnancy, the mechanisms by which their interaction impinge on maternal and placental health remain elusive. We used placentae from normotensive and preeclampsia pregnancy cohorts, human H9 embryonic stem cells differentiated into cytotrophoblast-like cells, and placenta-specific Phd2-/- preeclamptic mice. Lipid peroxidation and iron cargo of placenta-derived small extracellular vesicles (sEVs) isolated from the maternal circulation of control and preeclampsia individuals were examined by mass spectrometry, flow cytometry, and colorimetry. Human microvascular endothelial cells' angiogenic capacity and function were examined after exposure to control and pathological sEVs. Placentae from preeclampsia pregnancies contain increased ferrous iron and lipid peroxidation byproduct, malondialdehyde. Antioxidant capacity is significantly lower in preeclampsia placentae, with decreased glutathione content, and GPx4 (glutathione peroxidase 4) expression and activity. Hypoxia triggers the occurrence of ferroptosis in human trophoblast cells and mouse Phd2-/-placentae. Disrupted placental iron homeostasis in preeclampsia is accompanied by improper extrusion of iron through sEVs mediated by the pentaspan protein prominin-2. Heightened lipid peroxidation content was found in villous explants and maternal circulating sEVs of preeclampsia individuals. Exposure of human microvascular endothelial cells to preeclampsia-derived placental sEVs results in endothelial activation and impaired angiogenesis, which is rescued by treatment with hinokitiol, a compound known to restore tissue iron balance. In pregnancy, iron and oxygen work synergistically to conserve an operative antioxidant system to maintain iron homeostasis and protect the placenta from ferroptotic death. Hindrance to this system due to hypoxia results in heightened ferroptosis rates and sEV-mediated extrusion of harmful lipid peroxides from trophoblast cells into the circulation thereby contributing to maternal endothelial dysfunction characterizing preeclampsia.

Endothelial characteristics of cardiac stem cell antigen-1 expressing cells and their relevance to right ventricular adaptation.

A growing body of evidence suggest that the stem cell antigen-1 expressing (Sca-1+) cells in the heart may be the cardiac endothelial stem/progenitor cells. Their endothelial cell (EC) functions, and their role in RV physiology and pathophysiology of right heart failure (RHF) remains poorly defined. This study investigated EC characteristics of rat cardiac Sca-1+ cells, assessed spatial distribution and studied changes in Sca1+ cells during RV remodelling in monocrotaline (MCT) model of pulmonary hypertension and RV remodeling. First, flow cytometry analysis of adult male and female Sprague Dawley (SD) and Fischer CDF rat heart cells was performed, and we observed that the majority of Sca-1+ cells also expressed CD31, an EC marker. Furthermore, Sca-1+ cells showed acetylated low-density lipoprotein (ac-LDL) uptake and lectin binding similar to CD31+ cells from the same heart. The Sca-1+ cells also demonstrated network formation when plated on Matrigel. In the MCT treated rats, we observed increase in RV hypertrophy that correlated with the reduction in the abundance of Sca-1+CD31+ cells in the RV. Together, the cardiac Sca-1+ cells in the heart are endothelial stem/progenitor-like cells. These cells have higher abundance in the RV and may play a role in RV adaptation.

Polydopamine nanoparticles loaded with sodium ferulate for targeted therapy of myocardial infarction in endothelial cells.

Myocardial infarction (MI) is a leading cause of heart failure and death in cardiovascular diseases. Most drug trials currently fail due to inadequate local drug activity and side effects. In this study, we developed a novel polydopamine (PDA) nano delivery system that carries sodium ferulate (SF) and is modified with RGD peptides (SF/RGD-PDA NPs) for precise targeted delivery. SF is a clinical adjuvant for cardiovascular and cerebrovascular diseases but lacks targeting and has a short half-life. PDA, known for its excellent biocompatibility and surface modifiability, serves as an effective carrier. SF was loaded onto PDA through π-π stacking, while RGD was attached via a Michael addition reaction, resulting in stable SF/RGD-PDA NPs with an average particle size of 206.13 nm. In vitro and in vivo studies indicate that this targeted formulation has good safety. Targeting studies showed a 2.19-fold increase in nanoparticle accumulation in the heart and a 5.94-fold increase in cellular uptake efficiency. Pharmacodynamic studies revealed a 1.45-fold increase in endothelial cell proliferation, a 1.46-fold increase in angiogenesis rate, and a significant reduction in MI area. These findings suggest that SF/RGD-PDA NPs can improve endothelial cell function and reduce MI area through targeted delivery.

Pregnancy and Postpartum Effects of Electronic Cigarettes on Maternal Health and Vascular Function in the Fourth Trimester.

Pregnancy is a vulnerable time with significant cardiovascular changes that can lead to adverse outcomes, which can extend into the postpartum window. Exposure to emissions from electronic cigarettes (Ecig), commonly known as "vaping," has an adverse impact on cardiovascular function during pregnancy and post-natal life of offspring, but the postpartum effects on maternal health are poorly understood. We used a Sprague Dawley rat model, where pregnant dams are exposed to Ecigs between gestational day (GD)2-GD21 to examine postpartum consequences. Litter and dam health were monitored during the weaning period, and maternal vascular and endocrine function were assessed after weaning.Exposure to Ecig emissions during pregnancy led to fetal losses (i.e., reabsorption in utero) and reduced survival of pups during weaning compared to controls (air-exposed dams). We find that maternal vaping during pregnancy, with or without nicotine (or flavoring) results in maternal vascular and hormonal dysfunction (i.e., reduced prolactin, increased expression of sirtuin 1 deacetylase in the brain). Both5 and 30W Ecig aerosol exposures resulted in significant impairment of middle cerebral artery reactivity to acetylcholine-mediated dilation (decreasing ~ 22 and ~ 50%, respectively).We also observed an increase in the number of extracellular vesicles (EVs)in plasma from 30-W group that persists up to 3-week postpartum and that these EVs impaired endothelial cell function when applied to in vitro and ex vivo assays. Our data suggest (1) Ecig vaping, even without nicotine or flavorings, during pregnancy alters maternal circulating factors that influence maternal and fetal health, (2) circulating EVs may contribute to the etiology of vascular dysfunction, and (3) that the window for recovery from vascular dysfunction in the dam is likely to be longer than the exposure window.

Exosome-loading miR-205: a two-pronged approach to ocular neovascularization therapy

Pathological neovascularization is a hallmark of many vision-threatening diseases. However, some patients exhibit poor responses to current anti-VEGF therapies due to resistance and limited efficacy. Recent studies have highlighted the roles of noncoding RNAs in various biological processes, paving the way for RNA-based therapeutics. In this study, we report a marked down-regulation of miR-205 under pathological conditions. miR-205 potently inhibits endothelial cell functions critical for pathological neovascularization, including proliferation, migration, and tube formation. Furthermore, miR-205 strengthens the endothelial barrier, thereby reducing vascular leakage. In mouse models of retinal and choroidal neovascularization, miR-205 administration effectively suppresses abnormal blood vessel formation and leakage. Mechanistically, miR-205 directly targets VEGFA and ANGPT2, which are key drivers of pathological neovascularization. To improve delivery, we successfully loaded miR-205 into exosomes derived from mesenchymal stem cells. This innovative approach avoids cytotoxicity while preserving therapeutic efficacy in both cellular and animal models. Collectively, our findings highlight miR-205 as a promising therapeutic for ocular neovascularization, with exosome delivery offering a novel and efficient strategy for treating vision-threatening vascular diseases.Graphical

Androgenic Anabolic Steroids Cause Thiol Imbalance in the Vascular Endothelial Cells.

Androgenic anabolic steroids (AASs) are synthetic drugs structurally related to testosterone, with the ability to bind to androgen receptors. Their uncontrolled use by professional and recreational sportspeople is a widespread problem. AAS abuse is correlated with severe damage to the cardiovascular system, including changes in homeostasis and coagulation disorders. AASs alter vascular function by blocking nitric oxide (NO)-mediated dilation, impairing endothelial growth and by potentiating vasoconstrictor signals. This paper demonstrated that long-term use of AASs (nandrolone and boldenone), negatively affects the basic cell functions of vascular endothelial cells. The susceptibility of endothelial cells to AASs depends on the expression of androgen receptors, although cells without androgen receptors can also be affected by high doses of AASs to a limited extent. Seven-day incubation with AASs diminishes endothelial cell proliferation and migration (determined by transwell and scratch migration assay) and monolayer formation (using transendothelial electrical resistance assay). Disturbances in cell function were accompanied by downregulation of peroxiredoxins (PRDX1 and PRDX2), involved in maintaining the thiol-disulphide balance. In addition, AASs increased oxidation of the non-enzymatic thiol buffer, glutathione (GSH), reduced secretion of thiol oxidoreductase protein disulphide isomerase (PDI) from endothelial cells and affected the thiol pattern of PDI. These changes may be related to a thiol-disulfide imbalance and vascular endothelium dysfunction, that are often correlated with abnormal platelet aggregation, inflammation, increased vascular permeability, and vascular smooth muscle cell proliferation-all of which are observed in athletes who abuse AASs.

MFN2-mediated decrease in mitochondria-associated endoplasmic reticulum membranes contributes to sunitinib-induced endothelial dysfunction and hypertension.

Both in vitro and in vivo experiments performed to assesse reactive oxygen species (ROS), nitric oxide (NO), endothelium-dependent vasorelaxation, systemic blood pressure, and mitochondrial function in human umbilical vein endothelial cells (HUVECs) and C57BL/6 mouse aortic endothelial cells, under vehicle or sunitinib treatment condition. Sunitinib increased mitochondrial ROS accumulation, decreased oxygen consumption rate, ATP production, and mitochondrial calcium ([Ca2+]M) levels, and impaired endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) signaling in HUVECs. In addition, sunitinib also decreased mitochondrial membrane potential, elongated mitochondria, and reduced MAMs. Remarkably, these effects were reversed by an adeno-virus linker (Ad-linker) that reinforces MAMs. Engineered augmentation of MAMs using AAV-FLT1-linker significantly mitigated sunitinib-induced hypertension, by restoring endothelium-dependent relaxation in mice, highlighting the crucial role of MAMs in this process. Further analyses revealed that sunitinib enhanced Akt-mediated expression of mitofusin 2 (MFN2), causing mitochondrial elongation, and induced dephosphorylation of inositol 1,4,5-trisphosphate receptor type 1 (IP3R1) at residues Y1737/Y1738, reducing [Ca2+]M. Our study suggests that increased MFN2 expression and IP3R1 dephosphorylation are critical in sunitinib-induced MAMs reduction and [Ca2+]M homeostasis. Sunitinib induces mitochondrial dysfunction, Akt/MFN2-mediated decrease in MAMs and mitochondrial elongation, and IP3R1 dephosphorylation in endothelial cells, leading to endothelial dysfunction and hypertension. Our results provide the potential therapeutic targets for combating TKI-induced hypertension.

Cadmium-induced iron dysregulation contributes to functional impairment in brain endothelial cells via the ferroptosis pathway.

Cadmium (Cd2+) is a heavy metal that is a major hazardous environmental contaminant, ubiquitously present in the environment. Cd2+ exposure has been closely associated with an increased prevalence and severity of neurological and cardiovascular diseases (CVD). The blood-brain barrier (BBB) plays a crucial role in protecting the brain from external environmental factors. Mitochondria play an important role in maintaining the barrier function of brain endothelial cells by regulating energy metabolism and redox homeostasis. In this study, we aimed to assess the cytotoxic effects of Cd2+ on the integrity and function of brain endothelial cells. After 24h of exposure, Cd2+ reduced cell survival, tight junction protein expression, and trans-endothelial electrical resistance (TEER) in bEnd.3 cells suggest a potential BBB integrity disruption by Cd2+ exposure. To clarify the underlying mechanism, we further investigated the role of mitochondria in iron overload-mediated cell death following Cd2+ exposure. Cd2+ induced a substantial reduction in mitochondrial basal respiration and ATP production in brain endothelial cells, suggesting mitochondrial dysfunction. In addition, Cd2+ exposure led to impaired autophagy, elevated iron levels, and increased lipid peroxidation, indicating the initiation of ferroptosis, a form of cell death triggered by iron. In summary, our research suggests that Cd2+ exposure can disrupt BBB function by causing mitochondrial dysfunction and disrupting iron homeostasis.

Trimetazidine: Activating AMPK Signal to Ameliorate Coronary Microcirculation Dysfunction after Myocardial Infarction.

Myocardial ischemia-reperfusion (I/R) injury and coronary microcirculation dysfunction (CMD) are observed in patients with myocardial infarction after vascular recanalization. The antianginal drug trimetazidine has been demonstrated to exert a protective effect in myocardial ischemia-reperfusion injury. This study aimed to investigate the role of trimetazidine in endothelial cell dysfunction caused by myocardial I/R injury and thus improve coronary microcirculation. The myocardial I/R mouse model was established, and trimetazidine was administered for 7 days before myocardial I/R model establishment. Echocardiography, 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (H&E) staining, and thioflavin S staining were applied to assess myocardial injury and microvascular function. Additionally, the oxygen-glucose deprivation/reperfusion (OGD/R) model was developed in endothelial cells to simulate myocardial I/R injury in vitro. Griess reaction method, immunofluorescence, and western blotting (WB) were employed to detect the expressions of nitric oxide (NO), platelet endothelial cell adhesion molecule-1 (CD31) and vascular endothelial (VE)-cadherin, zonula occludens protein 1 (ZO-1), occludin, vascular endothelial growth factor (VEGF) and adenosine monophosphate (AMP)-activated protein kinase (AMPK) signaling-related proteins in endothelial cells and mouse cardiomyocytes. AMPK pathway inhibitor compound C was used for further mechanism validation. Our research demonstrated that trimetazidine can alleviate myocardial pathological injury and cardiac function injury during myocardial I/R. Trimetazidine was observed to improve microvascular reflux phenomenon and microvascular function and barrier injury in myocardial I/R and OGD/R models. Additionally, the expressions of AMPK signal-related proteins were found to be inhibited in myocardial I/R and OGD/R models, which were then activated in mice administered trimetazidine. However, the effects of trimetazidine on endothelial cell function and barrier damage were attenuated after co-treatment with compound C and trimetazidine. Trimetazidine ameliorated myocardial I/R-induced CMD by activating AMPK signaling.

Vascular Cell Adhesion Molecule 1 and E-Selectin as Potential Cardiovascular Risk Biomarkers in Psoriasis.

Vascular cell adhesion molecule-1 (VCAM-1) and E-selectin are involved in different inflammatory diseases and may be potential cardiovascular risk biomarkers in psoriasis. They play an important role in regulating the recruitment and adhesion to endothelial cells during inflammation, affecting various conditions like vasculitis, atherosclerosis, and cardiovascular diseases. Positive outcomes have been observed when using Tumor Necrosis Factor Alpha (TNF-α) inhibitors and biological therapies that target selectins to control the functioning of endothelial cells and reduce inflammation in psoriasis and related conditions. Moreover, the effects of systemic treatments and ultraviolet B (UVB) phototherapy on VCAM-1 and E-selectin levels in psoriasis patients highlights the potential to impact the severity of psoriasis and activation of endothelial cells. In addition, various factors such as age, sex, metabolic syndrome, hyperglycemia, migraines, and tobacco smoking have been found to affect levels of VCAM-1 and E-selectin. This sheds light on understanding the complex relationship between endothelial activation and the development of diseases. Studies show the potential of using the levels of VCAM-1 and E-selectin as indicators of systemic treatment effectiveness and the progression of the disease. In summary, this review highlights the importance of VCAM-1 and E-selectin as potential biomarkers for assessing inflammation, disease severity and cardiovascular risk in individuals with psoriasis. The shared mechanisms of psoriasis and atherosclerosis, along with the effect of treatments on endothelial activation markers, provide significant insights for further research and approaches to manage inflammatory diseases in the future.