TL;DR: The contributions of MMPs and TIMPs to atherosclerotic plaque expansion, neovascularization, and rupture vulnerability are reviewed with an interest in promoting targeted therapies to improve plaque stabilization and decrease the risk of major cardiovascular events.
Abstract: The prevalence of atherosclerotic disease continues to increase, and despite significant reductions in major cardiovascular events with current medical interventions, an additional therapeutic window exists. Atherosclerotic plaque growth is a complex integration of cholesterol penetration, inflammatory cell infiltration, vascular smooth muscle cell (VSMC) migration, and neovascular invasion. A family of matrix-degrading proteases, the matrix metalloproteinases (MMPs), contributes to all phases of vascular remodeling. The contribution of specific MMPs to endothelial cell integrity and VSMC migration in atherosclerotic lesion initiation and progression has been confirmed by the increased expression of these proteases in plasma and plaque specimens. Endogenous blockade of MMPs by the tissue inhibitors of metalloproteinases (TIMPs) may attenuate proteolysis in some regions, but the progression of matrix degeneration suggests that MMPs predominate in atherosclerotic plaque, precipitating vulnerability. Plaque neovascularization also contributes to instability and, coupling the known role of MMPs in angiogenesis to that of atherosclerotic plaque growth, interest in targeting MMPs to facilitate plaque stabilization continues to accumulate. This article aims to review the contributions of MMPs and TIMPs to atherosclerotic plaque expansion, neovascularization, and rupture vulnerability with an interest in promoting targeted therapies to improve plaque stabilization and decrease the risk of major cardiovascular events.
TL;DR: External elastase application mimics an acute inflammatory aneurysm, whereas intraluminal elastases perfusion shows chronic inflammation with angiogenesis and endothelial destruction, thus better mimicking human disease.
Abstract: Topical application of elastase to induce arterial aneurysm formation is an emerging murine model of vascular disease. In the context of aortic abdominal aneurysm (AAA), angiotensin II infusion and porcine pancreatic elastase perfusion models are commonly used today. This study, therefore, compares matrix remodeling, inflammation, and angiogenesis as distinct features of aneurysms in two models treated with intra-/extraluminal elastase. C57BL/6 mice underwent intra-/extraluminal elastase application via laparotomy and were followed up for 4 weeks. Basic histology and immunohistochemistry were performed at different time points along with transmission electron microscopy, PCR analysis, TUNEL assays, and blood analysis. Both models did not differ in aneurysm growth rate, but they showed distinct features and results depending on the way of elastase application. Extraluminal aneurysm induction preserved endothelial cell function and elastic fibers but showed ongoing acute inflammation, mainly in the adventitia. The destruction of elastic layers followed by chronic inflammation was a characteristic of intraluminal elastase perfusion, as well as medial angiogenesis, a key feature in human AAA. Different animal models harbor different features of human AAA and must, therefore, be chosen wisely. External elastase application mimics an acute inflammatory aneurysm, whereas intraluminal elastase perfusion shows chronic inflammation with angiogenesis and endothelial destruction, thus better mimicking human disease.
TL;DR: Data suggest that the circadian clock may be a biomechanical and temporal sensor that acts to coordinate timing, flow dynamics, and endothelial function.
Abstract: The circadian clock is rhythmically expressed in blood vessels, but the interaction between the circadian clock and disturbed blood flow remains unclear. We examined the relationships between BMAL1 and CLOCK and 2 regulators of endothelial function, AKT1 and endothelial nitric oxide synthase (eNOS), in vascular regions of altered blood flow. We found that the aortic arch from WT mice exhibited reduced sensitivity to acetylcholine (Ach)-mediated relaxation relative to the thoracic aorta. In Clock-mutant (mut) mice the aorta exhibited a reduced sensitivity to Ach. In WT mice, the phosphorylated forms of eNOS and AKT were decreased in the aortic arch, while BMAL1 and CLOCK expression followed a similar pattern of reduction in the arch. In conditions of surgically induced flow reduction, phosphorylated-eNOS (serine 1177) increased, as did p-AKT in the ipsilateral left common carotid artery (LC) of WT mice. Similarly, BMAL1 and CLOCK exhibited increased expression after 5 days in the remodeled LC. eNOS expression was increased at 8 p.m. versus 8 a.m. in WT mice, and this pattern was abolished in mut and Bmal1-KO mice. These data suggest that the circadian clock may be a biomechanical and temporal sensor that acts to coordinate timing, flow dynamics, and endothelial function.
TL;DR: It is suggested that high concentrations of sEng in plasma in combination with a high-fat diet induce the simultaneous activation of proinflammatory, pro-oxidative and vasoprotective mechanisms in mice aorta and the balance of these biological processes determines whether the final endothelial phenotype is adaptive or maladaptive.
Abstract: Aims: A soluble form of endoglin (sEng) was proposed to participate in the induction of endothelial dysfunction in small blood vessels. Here, we tested the hypoth
TL;DR: Overexpression of HFABP induces multiple pathway-related promotion of inflammation, growth and migration in vascular SMCs, suggesting a potential role in coronary artery ISR.
Abstract: Background: Our previous study suggested that heart-type fatty acid-binding protein (HFABP) levels were greatly elevated in the conditioned medium of explant culture of in-stent restenosis (ISR) tissue from diabetic minipigs compared with those of non-ISR tissue. We here verified this result in animal tissues and investigated the impact of HFABP overexpression in human aortic smooth muscle cells (hASMCs). Methods and Results: In Western blot and real-time RT-PCR, HFABP protein and mRNA levels were significantly higher in ISR than in non-ISR tissues from minipigs, and higher in the ISR tissue from diabetic minipigs than that from nondiabetic minipigs. The mRNA microarray and cellular effects of hASMC retroviral overexpression of HFABP and vector was analyzed. Compared with vector, HFABP transduction activates multiple signaling pathways (e.g. adipokine, TGF-β, Toll-like receptor, Wnt, Hedgehog, ErbB and Notch) and promotes inflammation, growth and migration in hASMCs whereas the knockdown of HFABP by small hairpin RNA attenuates these effects. Conclusion: HFABP expression is significantly higher in ISR tissue than in non-ISR tissue from diabetic and nondiabetic minipigs. Overexpression of HFABP induces multiple pathway-related promotion of inflammation, growth and migration in vascular SMCs, suggesting a potential role in coronary artery ISR.
TL;DR: Angiotensin-(1-7) induces endothelium-dependent and NO-mediated relaxation, unmasks bradykinin responses via activation of mas and AT2 receptors, and restores acetylcholine-induced vasodilation in HS-fed rats.
Abstract: This study investigated the acute effects of angiotensin-(1-7) and AVE0991 on active tone and vasodilator responses to bradykinin and acetylcholine in isolated mesenteric arteries from Sprague-Dawley rats fed a high-salt (HS; 4% NaCl) versus a normal salt (NS; 0.4% NaCl) diet. Angiotensin-(1-7) and AVE0991 elicited relaxation, and angiotensin-(1-7) unmasked vasodilator responses to bradykinin in arteries from HS-fed rats. These effects of angiotensin-(1-7) and AVE0991 were inhibited by endothelium removal, A779, PD123319, HOE140 and L-NAME. Angiotensin-(1-7) also restored the acetylcholine-induced relaxation that was suppressed by the HS diet. Vasodilator responses to bradykinin and acetylcholine in the presence of angiotensin-(1-7) were mimicked by captopril and the AT2 receptor agonist CGP42112 in arteries from HS-fed rats. Thus, in contrast to salt-induced impairment of vascular relaxation in response to vasodilator stimuli, angiotensin-(1-7) induces endothelium-dependent and NO-mediated relaxation, unmasks bradykinin responses via activation of mas and AT2 receptors, and restores acetylcholine-induced vasodilation in HS-fed rats. AT2 receptor activation and angiotensin-converting enzyme (ACE) inhibition shared the ability of angiotensin-(1-7) to enhance bradykinin and acetylcholine responses in HS-fed rats. These findings suggest a therapeutic potential for mas and/or AT2 receptor activation and ACE inhibition in restoring endothelial function impaired by elevated dietary salt intake or other pathological conditions.
TL;DR: It is demonstrated that alisol A 24-acetate effectively reverses the phenotypic transformation and inhibits the migration of VSMCs, which may be associated with the suppression of the ERK1/2 signaling pathway.
Abstract: Alisol A 24-acetate, a triterpenoid extracted from Alisma orientale, has shown antiatherosclerotic actions. The purpose of this study was to evaluate the inhibition of alisol A 24-acetate on oxidized low-density lipoprotein (Ox-LDL)-induced phenotypic transformation and migration of rat vascular smooth muscle cells (VSMCs), and to explore the underlying mechanisms. VSMCs were pretreated with alisol A 24-acetate and a specific extracellular signal-regulated kinase (ERK) inhibitor, U0126, and then stimulated with 50 mg/l Ox-LDL in vitro. The expression of VSMC phenotypic marker SM22α was determined using immunocytochemistry, and the migration of VSMCs was detected using a scratch-wound healing assay. The expression of matrix metalloproteinase (MMP)-9, MMP-2, phosphorylated ERK1/2 (pERK1/2) and total ERK was determined. Ox-LDL treatment caused a reduction in SM22α expression, VSMC transformation to the synthetic phenotype, increased MMP-2 and MMP-9 synthesis, the extension of VSMC migration distance and the upregulation of pERK1/2 expression, while the addition of alisol A 24-acetate or U0126 resulted in the elevation of SM22α expression, VSMC transformation to the contractile phenotype, a reduction in MMP-2 and MMP-9 expression, the shortening of cell migration distance and decreased pERK1/2 expression. The results of this study demonstrate that alisol A 24-acetate effectively reverses the phenotypic transformation and inhibits the migration of VSMCs, which may be associated with the suppression of the ERK1/2 signaling pathway.
TL;DR: AdipoDren®, an association of a series of plant-derived natural complexes, would be useful to ameliorate conditions of altered lymphatic vasculature and to support the physiological functionality of the lymphatic endothelium.
Abstract: Lymphatic leakage can be seen as a detrimental phenomenon associated with fluid retention and deposition as well as gain of weight. Moreover, lymphatic dysfunction is associated with an inflammatory environment and can be a substrate for other health conditions. A number of treatments can ameliorate lymphatic vasculature: natural substances have been used as treatment options particularly suitable for their consolidated effectiveness and safety profile. Here we report the protective effect of AdipoDren®, an association of a series of plant-derived natural complexes, on lymphatic endothelium permeability promoted by interleukin-1 beta (IL-1β) and the associated molecular mechanisms. AdipoDren® demonstrated a protective effect on dermal lymphatic endothelial cell permeability increased by IL-1β. Reduced permeability was due to the maintenance of tight junctions and cell-cell localisation of occludin and zonula occludens-1 (ZO-1). Moreover, AdipoDren® reduced the expression of the inflammatory key element cyclooxygenase-2 (COX-2), while not altering the levels of endothelial and inducible nitric oxide synthases (eNOS and iNOS). The upregulation of antioxidant enzymatic systems (catalase and superoxide dismutase-1, SOD-1) and the downregulation of pro-oxidant markers (p22 phox subunit of NADPH oxidase) were also evident. In conclusion, AdipoDren® would be useful to ameliorate conditions of altered lymphatic vasculature and to support the physiological functionality of the lymphatic endothelium.
TL;DR: It is suggested that mitochondrial biogenesis is impaired in AAA in synthetic SMCs in the media, with the exception of newly formed supporting vessels in the adventitia where the mitochondrial markers seem to be intact.
Abstract: Introduction: Abdominal aortic aneurysm (AAA) is a complex and deadly vascular disorder. The pathogenesis of AAA includes destruction and phenotypic alterations of the vascular smooth muscle cells (VSMCs) and aortic tissues. PPARγ coactivator-1 alpha (PGC1α) regulates VSMC migration and matrix formation and is a major inducer of mitochondrial biogenesis and function, including oxidative metabolism. Methods: Protein and gene expression of PGC1α and markers for mitochondria biogenesis and cell type-specificity were analysed in AAA aortas from humans and mice and compared against control aortas. Results: Gene expression of PPARGC1A was decreased in human AAA and angiotensin (Ang) II-induced AAA in mice when compared to control vessels. However, high expression of PGC1α was detected in regions of neovascularisation in the adventitia layer. In contrast, the intima/media layer of AAA vessel exhibited defective mitochondrial biogenesis as indicated by low expression of PPARGC1A, VDAC, ATP synthase and citrate synthase. Conclusion: Our results suggest that mitochondrial biogenesis is impaired in AAA in synthetic SMCs in the media, with the exception of newly formed supporting vessels in the adventitia where the mitochondrial markers seem to be intact. To our knowledge, this is the first study investigating PGC1α and mitochondria biogenesis in AAA.
TL;DR: Pressurized carotid arteries from young and aged rats are studied by imaging from within the artery using gradient index fluorescence microendoscopy to study endothelial calcium signaling and decreases in endothelial pressure sensitivity may manifest as a loss of functionality and responsiveness in aging.
Abstract: Aging is the summation of many subtle changes which result in altered cardiovascular function. Impaired endothelial function underlies several of these changes and precipitates plaque development in larger arteries. The endothelium transduces chemical and mechanical signals into changes in the cytoplasmic calcium concentration to control vascular function. However, studying endothelial calcium signaling in larger arteries in a physiological configuration is challenging because of the requirement to focus through the artery wall. Here, pressure- and agonist-sensitive endothelial calcium signaling was studied in pressurized carotid arteries from young (3-month-old) and aged (18-month-old) rats by imaging from within the artery using gradient index fluorescence microendoscopy. Endothelial sensitivity to acetylcholine increased with age. The number of cells exhibiting oscillatory calcium signals and the frequency of oscillations were unchanged with age. However, the latency of calcium responses was significantly increased with age. Acetylcholine-evoked endothelial calcium signals were suppressed by increased intraluminal pressure. However, pressure-dependent inhibition of calcium signaling was substantially reduced with age. While each of these changes will increase endothelial calcium signaling with increasing age, decreases in endothelial pressure sensitivity may manifest as a loss of functionality and responsiveness in aging.
TL;DR: Loss- and gain-of-function approaches established direct evidence for P2Y2R involvement in neointimal hyperplasia and specific anti-P2Y 2R therapies may be used against restenosis and bypass graft failure.
Abstract: Objectives: Extracellular nucleotide release at the site of arterial injury mediates the proliferation and migration of vascular smooth muscle cells. Our aim was
TL;DR: This study highlights the role of Ang II in driving vascular manifestations of CKD and indicates that early treatment can significantly limit pathological changes.
Abstract: Background/Aims: Chronic kidney disease (CKD) is associated with large artery remodeling, endothelial dysfunction and calcification, with angiotensin II (Ang II)
TL;DR: In this article, the accumulation of cyclophilin A (CyPA) within atherosclerotic lesions is thought to be implicated in the progression of atherosclerosis, however, the sou
Abstract: Objective: Accumulation of cyclophilin A (CyPA) within atherosclerotic lesions is thought to be implicated in the progression of atherosclerosis. However, the sou
TL;DR: Elevated CAM expression was identified in mice with pneumonia, but not lung contusion, indicating that the type of inflammatory stimulus and the presence of infection drive the vein-wall response.
Abstract: Background/Aims: Pneumonia is a significant risk factor for the development of venous thrombosis (VT). Cell-adhesion molecules (CAMs) are linked to the pathogenes
TL;DR: The use of an IAS mounted on an SDF camera during serosal microvascular assessment improves the success rate of image acquisition and stability and reduces the time to stable image with no effect on the microcirculation.
Abstract: Aim: To investigate whether an image acquisition stabilizer (IAS) mounted on the sidestream dark field camera (SDF) during gastrointestinal surgery improves image stability and acquisition. Methods: Serosal SDF imaging was compared with SDF imaging combined with an IAS (SDF + IAS) during gastrointestinal surgery. Stability was assessed as the image drift in pixels and the time to obtain stable images. The success rate was determined as the percentage of analyzable images after recording. The effect of negative pressure from the IAS was determined during single-spot measurements and by comparing microvascular parameters between groups. Data are presented as mean ± SD. Results: Sixty serosal measurements were performed per group; 87% were successful in the SDF group and 100% in the SDF + IAS group (p = 0.003). Image drift in the SDF group was 148 ± 36 versus 55 ± 15 pixels in the SDF + IAS group; p Conclusion: The use of an IAS mounted on an SDF camera during serosal microvascular assessment improves the success rate of image acquisition and stability and reduces the time to stable image with no effect on the microcirculation.
TL;DR: Findings demonstrate that, as a downstream molecule of RhoA, septin 2 blunted the responses of AFs to Ang II by protecting α-tubulin acetylation, which suggests that se leptin 2 may serve as a potential therapeutic target for vascular injury.
Abstract: Phenotypic transformation from adventitial fibroblasts (AFs) to myofibroblasts (MFs) is critical for vascular remodeling. Septin 2 was found to be downregulated during the differentiation of AFs to MFs induced by angiotensin II (Ang II); however, the role of septin 2 in this process is still unknown. In this study, we investigate whether septin 2 contributes to the adventitial MF phenotypic modulation caused by Ang II. The decreased level of septin 2 and the increased expression of α-smooth muscle actin (α-SMA), a marker of MFs, were readily observed in Ang II-stimulated MF differentiation. After gene transfer of septin 2, the expression of α-SMA was markedly decreased and the MF migration response to Ang II was inhibited. Furthermore, the inhibition of RhoA, another molecule involved in MF phenotypic modulation, decreased the motility of MFs and the expression of septin 2 triggered in Ang II. Finally, transfection of septin 2 rescued the level of acetyl-α-tubulin in MFs. These findings demonstrate that, as a downstream molecule of RhoA, septin 2 blunted the responses of AFs to Ang II by protecting α-tubulin acetylation, which suggests that septin 2 may serve as a potential therapeutic target for vascular injury.
TL;DR: The results showed that the long-term administration of PPS has an advantage in reducing I/R kidney injury in diabetic rats, while high-dose, single-shot parenteral administration ofPPS prior to revascularization might be useful in nondiabetic rats.
Abstract: Acute kidney injury (AKI) remains an independent risk factor for mortality and morbidity after vascular surgery (affecting the renal arteries) or aortic surgery (requiring suprarenal aortic clamping). These types of vascular surgery produce renal ischemia/reperfusion (I/R) injury, a common cause of AKI. The present studies aimed at monitoring the course of renal I/R injury at the cellular level and investigating the efficacy of long-term preoperative and single-shot intraoperative administration of sodium pentosan polysulfate (PPS) to protect renal tissue from acute I/R injury both in native and diabetic kidneys in rats. Western blot analyses of the proapoptotic (bax) and antiapoptotic (bcl-2) signaling pathways, as well as the extent of DNA damage (phospho-p53), were performed. Oxidative stress followed upon the termination of malondialdehyde, reduced glutathione, thiol group, and superoxide dismutase plasma levels. Inflammatory changes were measured by the determination of serum tumor necrosis factor-α and interleukin-1 levels. Morphological changes were detected by histological examinations. Our results showed that the long-term administration of PPS has an advantage in reducing I/R kidney injury in diabetic rats, while high-dose, single-shot parenteral administration of PPS prior to revascularization might be useful in nondiabetic rats.
TL;DR: It is shown that PE explants give rise to CD31-positive vascular sprouts in the presence of basic fibroblast growth factor (bFGF) and 2 isoforms of vascular endothelial growth factor A (VEGF-A), i.e. VEGF-A120 and VEGf-A164.
Abstract: Angiogenesis contributes to the generation of the vascular bed but also affects the progression of many diseases, such as tumor growth. Many details of the molecular pathways controlling angiogenesis are still undefined due to the lack of appropriate models. We propose the proepicardial explant as a suitable model for studying certain aspects of angiogenesis. The proepicardium (PE) is a transient embryonic structure that contains a population of undifferentiated endothelial cells (ECs) forming a vascular net continuous with the sinus venosus. In this paper, we show that PE explants give rise to CD31-positive vascular sprouts in the presence of basic fibroblast growth factor (bFGF) and 2 isoforms of vascular endothelial growth factor A (VEGF-A), i.e. VEGF-A120 and VEGF-A164. Vascular sprouts exhibit differences in number, length, thickness and the number of branches, depending on the combination of growth factors used. Moreover, the ECs of the sprouts express various levels of mRNA for Notch1 and its ligand Dll4. Additionally, stimulation with bFGF/VEGF-A164 upregulates the expression of Lyve-1 antigen in the ECs in the sprouts. In summary, we present a new model for angiogenesis studies involving mouse PE as a source of ECs. We believe that our model may act as a supplementary assay for angiogenesis studies along with the existing models.
TL;DR: The results showed that mmLDL significantly impaired the acetylcholine-induced endothelium-dependent relaxation of mouse mesenteric arteries with markedly reduced pIC50 and Rmax values, and increases superoxide and nitrotyrosine levels, and damages endothelial microstructure with decreased KCa3.1 and KCa2.3 expression.
Abstract: Minimally modified low-density lipoprotein (mmLDL) is a well-known risk factor for cardiovascular diseases. The present study was designed to investigate the role of mmLDL in the endothelium-dependent
TL;DR: Evidence is provided that increased serum IL-6, IL-1β, and CRP levels around PCI are not different between different postdilation pressure and stent number groups and can augment mechanical strain-induced CRP synthesis via the SAC-NF-κB pathway in human IMAs.
Abstract: Background: C-reactive protein (CRP) is significantly associated with cardiovascular diseases; however, whether CRP plays a causal role in coronary artery disease has yet to be determined. In addition, the relationship between CRP, atherosclerosis, and inflammation remains controversial. Methods and Results: Serum interleukin (IL)-6, IL-1β, and CRP levels were determined in 160 patients at time points around percutaneous coronary intervention (PCI) with drug-eluting stent implantation. The levels were found to be at peak at 24 h post-PCI and gradually declined to the level before PCI at day 30 post-PCI. These inflammation markers around PCI have no statistical difference in the different postdilation pressures (≤14, 14-18, and ≥18 atm) and stent number (1 and ≥2 stents) groups. Treatment of cultured human vascular smooth muscle cells (VSMCs) with a combination of IL-6 and IL-1β at concentrations associated with PCI did not result in any significant change in the CRP mRNA levels. The IL-6-augmented CRP expression in human internal mammary arteries (IMAs) stretched with a mechanical strength of 3 g was blocked by the nuclear factor-κB (NF-κB) peptide inhibitor SN50 and not by the inactive SN50 analog SN50M. IL-6 treatment increased NF-κB activity in human IMAs stretched with 3 g, and this effect was further blocked by stretch-activated channel (SAC) inhibitors (streptomycin or GdCl3) and SN50. Conclusions: The current study provides evidence that increased serum IL-6, IL-1β, and CRP levels around PCI are not different between different postdilation pressure and stent number groups. The combination of IL-6 and IL-1β at concentrations associated with PCI cannot induce CRP expression in human VSMCs, but they can augment mechanical strain-induced CRP synthesis via the SAC-NF-κB pathway in human IMAs.
TL;DR: Vasodilation induced by nobiletin was dependent on the endothelium and partly on eNOS activation, which is mediated by high endothelial [Ca2+]i, and results suggestnobiletin may offer a therapeutic benefit and could potentially be used as a vasodilator for the treatment of hypertension.
Abstract: Aims: Nobiletin, a natural polymethoxylated flavonoid compound, has various beneficial properties, such as anticancer, anti-inflammatory, and antioxidant effects,
TL;DR: It is concluded that TRPV1 channels limit the vasomotor responses to changes in pH, which means that base-induced arterial contraction is regulated primarily by neural TRPv1 channels, and acid- induced arterial relaxation is modulated by TRP V1 channels located on nonneural vascular structures.
Abstract: pH changes can influence local blood flow, but the mechanisms of how acids and bases affect vascular tone is not fully clarified. Transient receptor potential vanilloid-1 (TRPV1) channels are expressed in vessels and can be activated by pH alterations. Thus, we hypothesized that TRPV1 channels are involved in the mediation of vascular responses to acid-base changes. Vasomotor responses to HCl, NaOH, and capsaicin were measured in isolated murine carotid and tail skin arteries. The function of TRPV1 was blocked by either of three approaches: Trpv1 gene disruption, pharmacological blockade with a TRPV1 antagonist (BCTC), and functional impairment of mainly neural TRPV1 channels (desensitization). In each artery type of control mice, HCl caused relaxation but NaOH contraction, and both responses were augmented after genetic or pharmacological TRPV1 blockade. In arteries of TRPV1-desensitized mice, HCl-induced relaxation did not differ from controls, whereas NaOH-induced contraction was augmented. All three types of TRPV1 blockade had more pronounced effects in carotid than in tail skin arteries. We conclude that TRPV1 channels limit the vasomotor responses to changes in pH. While base-induced arterial contraction is regulated primarily by neural TRPV1 channels, acid-induced arterial relaxation is modulated by TRPV1 channels located on nonneural vascular structures.
TL;DR: The results suggest that iron does accumulate in arterial tissue in accordance to the level of stored body iron, and further studies are needed on the distribution of iron in excess to explain the relationship between stored iron and the development of atherosclerosis.
Abstract: The association between increased amounts of stored iron and development of cardiovascular disease (CVD) has been recognized for many years. However, basic information on iron content in human arteries is limited. We envision that associations between body iron content and CVD are based on the accumulation of iron in the arteries, possibly leading to the dysfunction of cellular biochemical pathways. This study addresses the very fundamental question of whether there is a relation between body iron content and the level of iron accumulated in arterial tissue. The iron content in human nonatherosclerotic artery samples from patients with high and low body-iron contents estimated from the plasma ferritin concentration were determined by inductively coupled plasma mass spectroscopy in tissue extracts and by histological staining, using a modified Perls reaction to display iron deposits. We found that the arteries contained small but measurable levels of iron. The iron content was significantly higher in tissue from patients with high plasma ferritin (p = 0.026). Histological staining showed the presence of iron deposits. Our results suggest that iron does accumulate in arterial tissue in accordance to the level of stored body iron. Further studies are needed on the distribution of iron in excess to explain the relationship between stored iron and the development of atherosclerosis.
TL;DR: Transplantation of autologous BMMNCs delays the development of atherosclerosis, most probably via the attenuation of inflammatory responses, which could be a new approach for treating carotid Atherosclerosis.
Abstract: Objective: It is well known that inflammation plays key roles in the development of atherosclerosis and that the transplantation of bone marrow mononuclear cells
TL;DR: In vitro ASA pretreatment leads to significantly increased lysis rates due to a weaker fibrin mesh in platelet-rich plasma clots in patients with acute ischemic strokes.
Abstract: Background: Patients with acute ischemic strokes frequently take an acetylsalicylic acid (ASA) premedication. We determined the impact of ASA on different thrombo
TL;DR: The BM EPC functions and bioactivities in the KD models were impaired, and the Notch4 signaling pathway is associated with KD.
Abstract: The Notch4 signaling pathway of endothelial progenitor cells (EPCs) may play a crucial role in Kawasaki disease (KD). We investigated the proliferation, adhesion, migration, angiogenesis, and expression levels of Notch4, recombination signal-binding protein-Jκ (RBP-Jκ), P-selectin, and vascular cell adhesion molecule-1 (VCAM-1) of bone marrow (BM) EPCs in a KD model induced by Lactobacillus casei cell wall extract. The numbers of BM EPCs decreased significantly in the KD models. The Notch4 expression level on the EPC surface was higher in the KD models than in the controls. The proliferative, adhesive, migratory, and angiogenic properties, and double immunofluorescence-binding rate of BM EPCs were significantly impaired in the KD models. The levels of Notch4 and P-selectin mRNA were lower in the KD models than in the controls on day 3. The RBP-Jκ mRNA levels were lower in the KD models than in the controls on days 3 and 7. The levels of RBP-Jκ and vascular endothelial growth factor receptor-2 proteins decreased in the early stage. In conclusion, the BM EPC functions and bioactivities in the KD models were impaired, and the Notch4 signaling pathway is associated with KD.
TL;DR: Findings suggest that HMGB1 may not be a major player in cerebral vascular dilating dysfunction after SAH, and inhibitors ofHMGB1-receptor for advanced glycation end-product or HMGB 1-toll-like receptor 2/4 interaction, or the HMBG1 antagonist did not improve pial arteriole reactivity 48 h afterSAH.
Abstract: High-mobility group box 1 protein (HMGB1) has been implicated in inflammatory responses, and is also associated with cerebral vasospasm after subarachnoid hemorrhage (SAH). However, there are no direc
TL;DR: It is implied that hepatic tumors can develop resistance to antiangiogenic therapy by maintaining perfusion through portal venous perfusion by inducing rearrangement of the hepatic tumor vascular network to establish communication with the portal vein.
Abstract: Purpose: Hepatic malignancies can easily develop resistance to antiangiogenic therapy, but the underlying mechanism remains poorly understood. This study explores whether antiangiogenic therapy influences the tumor vascular network and/or the vessels feeding the hepatic tumor. Methods: Mice implanted with Lewis lung carcinoma (LLC) cells were subcutaneously injected 3 times (once every other day starting 1 week after LLC implantation) with either an antiangiogenic agent [vascular endothelial growth factor (VEGF)-Trap] or control agent (bovine serum albumin) at a dose of 25 mg/kg before performing angiography. Hepatic arteriography and portography were performed using a vascular cast method with vascular latex. Results: Arteriography of the control-treated LLC-implanted mice showed marked staining of the mass with a prominent feeding artery, suggesting that the tumor is supplied by arterial perfusion. No significant staining was observed on portography. By contrast, 33% (n = 3/9) of the LLC-implanted mice treated with the antiangiogenic agent VEGF-Trap showed intratumoral staining during portography, indicating that these tumors received perfusion via the portal vein. Conclusion: Antiangiogenic treatment can induce rearrangement of the hepatic tumor vascular network to establish communication with the portal vein. This implies that hepatic tumors can develop resistance to antiangiogenic therapy by maintaining perfusion through portal venous perfusion.