Artery Constriction Research Articles

Reversible Cerebral Vasoconstriction Syndrome Following Blood Transfusion in a Patient With Chronic Anemia: A Case Report.

Reversible cerebral vasoconstriction syndrome (RCVS) is a rare neurological disorder characterized by transient constriction and dilation of cerebral arteries, leading to severe headaches and neurological deficits. This case report describes a 41-year-old woman with chronic anemia, acute chronic kidney disease, type 2 diabetes mellitus, and rheumatoid arthritis who developed RCVS following transfusion of packed red blood cells (PRBCs). She experienced sudden-onset seizures and a thunderclap headache 5 days post-transfusion. Diagnostic imaging, including computed tomography (CT) and magnetic resonance imaging (MRI), revealed the characteristic features of vasogenic edema. The patient was treated with blood pressure control and symptomatic relief for pain, resulting in gradual improvement. This case highlights the importance of recognizing RCVS as a potential complication of blood transfusions, particularly in patients with significant comorbidities. Understanding the possible mechanisms, including rapid hemoglobin correction, and the effects of residual plasma and storage lesions in transfused blood, is essential to prevent and manage this rare but serious condition.

Acute effects of high-intensity interval training on microvascular circulation: a case control study in uveal melanoma

Abstract Objectives The aim of this study was to explore the acute effects of high-intensity interval training (HIIT) on the microvascular circulation and vascular tumor microenvironment (TME) in a patient with uveal melanoma (UM). Additionally, the acceptance of the applied diagnostics and the exercise protocol in a clinical ophthalmic-oncology setting were evaluated. Methods This case-control study included a young adult male patient with UM previously treated with radiation and an age-matched healthy control. Participants underwent a baseline assessment of dynamic retinal vessel analysis (DRVA) and cardiopulmonary exercise testing (CPET) to determine endothelial function and intensity for HIIT. Optical coherences tomography angiography (OCTA) was performed before, immediately and 30 min after one session of HIIT. The primary outcome were changes in ocular vessel parameters and whole body oxygen uptake. Results The UM patient exhibited lower arterial dilation and constriction in the affected eye compared to his healthy eye and both eyes of the healthy control. OCTA revealed heterogeneous patterns of vascular response to HIIT in both participants. The tumor eye showed an increase followed by a significant decrease in vessel density post-exercise, while the healthy control exhibited minor increases. Conclusions The findings of this study highlighted the potential of UM combined with OCTA and DRVA as a model for examine exercise-induced vascular effects within the TME. However, a pre-treated UM as well as detailed image analyses and further research with longitudinal, randomized controlled designs are essential to validate these findings and address methodological limitations. Such investigations could refine integrative cancer treatment.

Interleukin-22 inhibits right ventricular remodelling by a unique mechanism in a pulmonary artery constriction model

Abstract Background Fibrosis and remodeling of right ventricle (RV) are associated with prognosis in patients with RV failure. Interleukin-22 (IL-22) is a member of the IL-10 cytokine family, play roles in tissue protection and wound repair. We have previously shown that IL-22 plays an important role in cardiac remodeling after acute myocardial infarction; however, the role of IL-22 in RV fibrosis and remodeling remains elusive. Purpose We investigated the role of IL-22 in the pathogenesis of RV remodeling during pressure overload. Methods Pulmonary artery banding (PAB) is performed by placing a 6-0 suture around the pulmonary artery over a 24 G needle in wild type mice (C57BL/6J) and IL-22 knockout mice (IL-22 KO). Only mice with moderate pulmonary artery stenosis (peak pressure gradient across the pulmonary band: 25–40 mmHg at 1 week after surgery by echo Doppler) were included in the study protocol. Four weeks after PAB, RV function was measured by echocardiography and real-time PCR analysis was performed to measure Col1a1, Col3a1, BNP, and transcriptome analysis was performed. Survival confirmation of mice with moderate pulmonary artery stenosis was also performed up to 56 days. Results IL-22 KO mice had significantly higher 56-day mortality rate compared with WT mice after PAC (p<0.01). Four weeks after PAB, IL-22 KO mice showed markedly increased RV weight (IL-22 KO mice vs. wild-type mice; RV/LV+IVS: 0.48±0.05 vs 0.40±0.02, P=0.002). IL-22 KO mice exhibited significant RV enlargement and RV dysfunction 4 weeks after PAB. (IL-22 KO mice vs wild type mice; RVEDV: 10±2.3mm2 vs 12.9±3.1mm2, P=0.005, TAPSE: 10.8±1.8mm vs 9.5±1.7mm, P=0.04, FAC: 35.2±7.8% vs 23±6.0%, P<0.001). The expressions of Col1a1 and Col3a1 were no difference between in IL22-KO mice and Wild mice. However, BNP, a cardioprotective marker, tended to be lower in IL-22KO mice. The transcriptome analysis also showed that the group of fibrosis-related genes that are elevated in PAC in WT mice were less elevated in IL-22 KO mice. Conclusion These results suggest that IL-22 is involved in RV remodelling during RV pressure loading without a general mechanism.

Reversible Cerebral Vasoconstriction Syndrome

Reversible cerebral vasoconstriction syndrome (RCVS) is a collective term used to describe pathological conditions with a similar clinical and radiological picture which is characterized by thunderclap headaches with a sudden onset and reversible segmental (multifocal) constriction of the cerebral arteries. The article is devoted to issues of terminology, genetic and clinical features of RSCV, and also discusses risk factors, differential diagnosis, complications and prognosis. Modern pathogenetic mechanisms and possible approaches to the treatment of this condition are presented.

Perivascular Adipose Tissue Becomes Pro-Contractile and Remodels in an IL10-/- Colitis Model of Inflammatory Bowel Disease.

Inflammatory Bowel Diseases (IBDs) are associated with aberrant immune function, widespread inflammation, and altered intestinal blood flow. Perivascular adipose tissue (PVAT) surrounding the mesenteric vasculature can modulate vascular function and control the local immune cell population, but its structure and function have never been investigated in IBD. We used an IL10-/- mouse model of colitis that shares features with human IBD to test the hypothesis that IBD is associated with (1) impaired ability of PVAT to dilate mesenteric arteries and (2) changes in PVAT resident adipocyte and immune cell populations. Pressure myography and electrical field stimulation of isolated mesenteric arteries show that PVAT not only loses its anti-contractile effect but becomes pro-contractile in IBD. Quantitative immunohistochemistry and confocal imaging studies found significant adipocyte hyperplasia and increased PVAT leukocytes, particularly macrophages, in IBD. PCR arrays suggest that these changes occur alongside the altered cytokine and chemokine gene expression associated with altered NF-κB signaling. Collectively, these results show that the accumulation of macrophages in PVAT during IBD pathogenesis may lead to local inflammation, which ultimately contributes to increased arterial constriction and decreased intestinal blood flow with IBD.

Cerebral Artery Vasoconstriction After Galcanezumab Loading Dose for Migraine Prevention: A Case Report.

Anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies that target CGRP ligands or receptors, may cause a very rare side effect of reversible cerebral vasoconstriction syndrome (RCVS). This study is a case report of a patient who developed cerebral artery vasoconstriction documented on serial brain magnetic resonance angiography (MRA) scans without the typical manifestations of RCVS following galcanezumab loading dose. Case report: A 40-year-old female patient with high-frequency episodic migraine with visual aura on topiramate 100mg/day developed transient numbness of the right upper and lower extremities and right face without headache and a normal neurological examination 10min after a loading dose of galcanezumab, which resolved over the next 2days. Magnetic resonance angiography brain imaging showed segmental arterial constriction of both middle cerebral arteries in the M1-2 segments and both posterior cerebral arteries in the P1-2 segments, which partial resolved in a subsequent study by the end of 6months. There were no other supporting examination data, such as transcranial Doppler, which might provide additional information on the progression and improvement of the vasoconstriction. Her differential diagnosis included prolonged migraine sensory aura without headache, RCVS, or cerebral vasoconstriction secondary to the effect of an anti-CGRP monoclonal antibody. Further research needs to be conducted.

The role of biomarkers on hemodynamics in atherosclerotic artery

Atherosclerosis, a chronic inflammatory cardiovascular disease, leads to arterial constriction caused by the accumulation of lipids, cholesterol, and various substances within artery walls. Such plaque can rupture, resulting in a blood clot that obstructs major arteries and may initiate myocardial infarction, ischemic stroke, etc. Atherosclerotic plaque formation begins with the accumulation of foam cells and macrophages within the intima layer of the arterial wall. At the latter stage, the smooth muscle cells migrated from deeper artery wall layers, contributing to the fibrous cap formation and plaque stabilizing. A developed plaque gradually enters the lumen and narrows down the lumen to impede blood flow. We introduce a two-phase and macroscopic model to investigate the progression of plaque growth in its advanced stage and analyze the minimum gap (Lumen Clearance) within an atherosclerotic artery so that blood cells can pass through. Cardiac troponin, a high specificity and sensitivity biomarker, facilitates early detection of elevated myocardial infarction, ischemic stroke risks, etc. This study aims at establishing a relationship between the troponin concentration in atherosclerotic arteries and their internal clearance, which could significantly improve our understanding of disease progression. Our observations show that the plaque undergoes rapid evolution in its initial stages, gradually slowing down over time to reach a stable state. A positive correlation exists between the maximum plaque depth and cardiac troponin concentration in the blood. However, the lumen clearance exhibits the opposite behavior. The speed of blood cells slows down at an enhanced plaque depth within atherosclerotic arteries.

Abstract P139: Exploring the cardiometabolic effects of lipid 12-hydroxyeicosapentaenoic acid through thromboxane receptor partial agonism

Introduction: It is well known that lipid mediators secreted by brown adipose tissue (BAT) during cold exposure or beta-adrenergic stimulation can exert beneficial effects on glucose and lipoprotein homeostasis. Recently, Leiria et al. demonstrated that one of these mediators, 12-hydroxyeicosapentaenoic acid (12-HEPE), secreted by BAT, enhances glucose tolerance and insulin sensitivity through the stimulation of a G protein-coupled receptor (GPCR). However, the receptor that 12(S)-HEPE binds to exert its functions was unknown. Therefore, this study aimed to identify the GPCR that 12-HEPE binds to and to investigate whether 12-HEPE affects vascular reactivity. Methods: Screening of 70 non-olfactory GPCR candidates was conducted in HEK293 cells, either stimulated or not with 12-HEPE (5µM). Receptor activation was measured using the dynamic mass redistribution (DRM) assay. After identifying the potential receptor, we validated the result by monitoring intracellular Ca2+ levels through a dose-response curve for 12-HEPE. To study the biological effects resulting from this ligand-receptor interaction, thoracic aortic artery rings were isolated from 12-week-old C57BL6 male mice, and their contractile responses were monitored using a myograph in response to cumulative doses ranging from 100pM to 10µM of 12-HEPE. Results: Through DRM screening, we found that the thromboxane receptor (TP) exhibited the strongest interaction with 12(S)-HEPE (5µM). To validate the screening, we incubated HEK293 cells with 12-HEPE or U46619 and quantified intracellular calcium mobilization. Our data demonstrate that 12-HEPE is a partial TP agonist, with an EC50 of 314nM compared to 7.2nM for U46619. Furthermore, incubation of the thoracic aorta with 12-HEPE produced dose-dependent increases in arterial constriction (pEC50: 6.129 ± 0.174; Emax: 95.39 ± 15.72), and this effect was completely prevented by the thromboxane antagonist, TPA (1µM). Conclusions: Our results suggest that 12-HEPE is an endogenous partial agonist of the TP receptor, and such interaction is necessary for the biological effects of these lipids. Importantly, the vasoconstrictor effect mediated by 12-HEPE may be an important physiological adaptation to prevent body heat loss upon cold exposure, thus allowing for adequate temperature maintenance.

Advancing Blood Flow in Stenotic Arteries through Magnetohydrodynamic Peristaltic Motion of Hybrid Nanoparticles

This research aims to investigate the efficacy of hybrid nanoparticles in improving magnetohydrodynamic (MHD) peristaltic blood flow in stenotic arteries. Hybrid nanoparticles combining MHD processes and peristaltic motion show promise for increasing blood flow through constricted arteries. To evaluate the impact of nanoparticles on blood flow parameters, researchers use theoretical modelling and analytical solutions. Incorporating copper and aluminium oxide nanoparticles (Cu-Al2O3) into blood, leading to the formation of an ionic solution, is a crucial step in creating a homogeneous hybrid blood suspension. The mathematical model uses approximations of the stenosis and non-dimensional parameters for a mild stenosis scenario to simplify the underlying coupled nonlinear partial differential equations. Analytical solutions for various blood flow parameters such as velocity, temperature, stream function, wall shear stress, Nusselt number, and flow resistance impedance are obtained using the perturbation technique. This study visually analyzes how different physiological variables affect arterial blood flow characteristics. The heat conductivity of blood is an essential aspect of preserving one's sustenance, which is largely determined by the concentration of hybrid nanoparticles. A streamlined pattern depicts the direction of blood flow within an artery. This research demonstrates that the adverse effects of vascular stenosis can be mitigated by using hybrid nanoparticles. In order to aid narrowed arteries, these nanoparticles lessen wall shear stress, boost axial flow speed, and enhance the velocity profile.

Management of Psychiatric Diagnoses in Reversible Cerebral Vasoconstriction Syndrome: The Dangers of Worsening Pathology with Serotonergic Medications: A Case Report and Literature Review.

Reversible cerebral vasoconstriction syndrome (RCVS) represents a group of conditions that show reversible multifocal narrowing or constriction of the cerebral arteries that supply blood to the brain. The initial manifestation of RCVS often includes a "thunderclap" headache that is sudden, severe, and often disabling. Stimulants, selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and antipsychotics with serotonergic activity can alter the cerebral arterial tone, trigger vasoconstriction, and place patients at risk of a cerebrovascular accident. Thus, psychiatric medications are commonly discontinued on admission for RCVS, and psychiatry is often consulted for input on acute medication management and longitudinal treatment options. Currently, there is a dearth of literature on managing psychiatric medications in RCVS, resulting in variable practice patterns that place patients at risk of withdrawal, decompensation, and relapse. In this article, we provide a case example and aim to consolidate the limited data surrounding the management of psychiatric illness with comorbid RCVS in our discussion. There is a clear concern about worsening and even potentially lethal consequences due to serotonin or stimulant-induced vasospasm both during an acute episode and in long-term management of RCVS. We discuss the underlying pathophysiologic mechanisms proposed for serotonergic-, noradrenergic-, and dopaminergic-induced cerebral vasospasm and how this correlates with the clinical management of patients on psychiatric medications. These data will then be organized to create a risks versus benefits outline to equip psychiatrists to make decisions about when to stop and when to restart psychiatric medications in the setting of RCVS.

Effect of Sumatriptan in an Adult with Meningitis-Induced Severe Headache: a Case Report

Meningitis is a serious neurological condition caused by inflammation of the meninges due to infection. Meningitis typically triggers symptoms of severe headaches, high fever, and neck stiffness. In this case, we evaluate the effect of sumatriptan on meningitis-induced severe headache and the underlying pathophysiology. In this case report, we present a patient with no history of migraine with a meningitis-induced headache. The patient did not experience analgesic relief from paracetamol, ibuprofen, or tramadol, but significant relief was achieved after the administration of sumatriptan. While treating his headache, diagnostic interventions such as lumbar puncture were done, and PCR analysis of the cerebrospinal fluid identified varicella-zoster virus. The patient experienced a significant analgesic effect from sumatriptan, possibly due to constriction of the meningeal arteries, blocking of meningeal inflammation, or both.

The Beneficial Effect of the SGLT2 Inhibitor Dapagliflozin in Alleviating Acute Myocardial Infarction-Induced Cardiomyocyte Injury by Increasing the Sirtuin Family SIRT1/SIRT3 and Cascade Signaling.

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) have a variety of cardiovascular and renoprotective effects and have been developed as novel agents for the treatment of heart failure. However, the beneficial mechanisms of SGLT2i on cardiac tissue need to be investigated further. In this study, we established a mouse model of acute myocardial infarction (AMI) using coronary artery constriction surgery and investigated the role of dapagliflozin (DAPA) in protecting cardiomyocytes from hypoxic injury induced by AMI. In vitro experiments were done using hypoxic cultured H9c2 ventricular cells to verify this potential mechanism. Expression of the SIRT family and related genes and proteins was verified by qPCR, Western blotting and immunofluorescence staining, and the intrinsic potential mechanism of cardiomyocyte death due to AMI and hypoxia was comprehensively investigated by RNA sequencing. The RNA sequencing results of cardiomyocytes from AMI mice showed that the SIRT family may be mainly involved in the mechanisms of hypoxia-induced cardiomyocyte death. In vitro hypoxia-induced ventricular cells showed the role of dapagliflozin in conferring resistance to hypoxic injury in cardiomyocytes. It showed that SIRT1/3/6 were downregulated in H9c2 cells in a hypoxic environment, and the addition of dapagliflozin significantly increased the gene and protein expression of SIRT1, 3 and 6. We then verified the underlying mechanisms induced by dapagliflozin in hypoxic cardiomyocytes using RNA-seq, and found that dapagliflozin upregulated the hypoxia-induced gene downregulation, which includes ESRRA, EPAS1, AGTRAP, etc., that associated with SIRTs-related and apoptosis-related signaling to prevent H9c2 cell death. This study provides laboratory data for SGLT2i dapagliflozin treatment of AMI and confirms that dapagliflozin can be used to treat hypoxia-induced cellular necrosis in cardiomyocytes, in which SIRT1 and SIRT3 may play an important role. This opens up further opportunities for SGLT2i in the treatment of heart disease.

Mathematical Modeling of the Physics of Blood Flow along a Constricted Artery during Treatment of Cancer using Hyperthermia

A numerical investigation of a unidirectional unsteady flow of blood and heat transfer through an artery with a stenotic condition during heat therapy has been performed aiming at determining the dynamics of fluid (blood) flow and heat transfer. Blood is treated to obey the Newtonian law of viscosity. The arterial wall is considered to be rigid due to the presence of stenosis. Heat transfer has been studied under the presence of external heat source that is used to raise body temperature during treatment under hyperthermia. The formulated model equations have been solved using finite difference scheme and simulations are done using MATLAB software. Velocity and temperature profiles have been plotted subject to varying some flow parameters such as Reynolds number, Pranditl number, Eckert number and heat the source parameter. Skin friction and Nusselt number have been plotted to see their varying behavior during heat therapy. A validation of this formulation is shown by comparing the current findings with those from the existing literature.

Exploring the Therapeutic Potential of C-Type Natriuretic Peptide for Preeclampsia.

Preeclampsia is a serious condition of pregnancy, complicated by aberrant maternal vascular dysfunction. CNP (C-type natriuretic peptide) contributes to vascular homeostasis, acting through NPR-B (natriuretic peptide receptor-B) and NPR-C (natriuretic peptide receptor-C). CNP mitigates vascular dysfunction of arteries in nonpregnant cohorts; this study investigates whether CNP can dilate maternal arteries in ex vivo preeclampsia models. Human omental arteries were dissected from fat biopsies collected during cesarean section. CNP, NPR-B, and NPR-C mRNA expression was assessed in arteries collected from pregnancies complicated by preeclampsia (n=6) and normotensive controls (n=11). Using wire myography, we investigated the effects of CNP on dilation of arteries from normotensive pregnancies. Arteries were preconstricted with either serum from patients with preeclampsia (n=6) or recombinant ET-1 (endothelin-1; vasoconstrictor elevated in preeclampsia; n=6) to model vasoconstriction associated with preeclampsia. Preconstricted arteries were treated with recombinant CNP (0.001-100 µmol/L) or vehicle and vascular relaxation assessed. In further studies, arteries were preincubated with NPR-B (5 µmol/L) and NPR-C (10 µmol/L) antagonists before serum-induced constriction (n=4-5) to explore mechanistic signaling. CNP, NPR-B, and NPR-C mRNAs were not differentially expressed in omental arteries from preeclamptic pregnancies. CNP potently stimulated maternal artery vasorelaxation in our model of preeclampsia (using preeclamptic serum). Its vasodilatory actions were driven through the activation of NPR-B predominantly; antagonism of this receptor alone dampened CNP vasorelaxation. Interestingly, CNP did not reduce ET-1-driven omental artery constriction. Collectively, these data suggest that enhancing CNP signaling through NPR-B offers a potential therapeutic strategy to reduce systemic vascular constriction in preeclampsia.

Reversible Cerebral Vasoconstriction Syndrome with Subarachnoid Hemorrhage and Stroke

AbstractReversible cerebral vasoconstriction syndrome is a complex condition characterized by temporary constriction of the brain's arteries. Diagnosis typically involves a retrospective approach, necessitating repeated imaging to confirm the resolution of cerebral arterial spasms. We describe a case of a 22-year-old female with a history of posterior circulation stroke and recurrent thunderclap headaches. On imaging, evidence of stroke, convexity subarachnoid hemorrhage, and multiple areas of stenosis and dilatation in the posterior circulation associated with normal laboratory parameters were found. The resolution of clinical symptoms and angiographic findings were noted in the follow-up. After other diagnoses are excluded, patients can be reassured about favorable prognosis.

Factors Contributing to Coronary Microvascular Dysfunction in Patients with Angina and Non-Obstructive Coronary Artery Disease.

Coronary microvascular dysfunction (CMD), characterised by a reduced coronary flow reserve (CFR) or an increased index of microcirculatory resistance (IMR), has received considerable attention as a cause of chest pain in recent years. However, the risks and causes of CMD remain unclear; therefore, effective treatment strategies have not yet been established. Heart failure or coronary artery disease (CAD) is a risk factor for CMD, with a higher prevalence among women. However, the other contributing factors remain unclear. In this study, we assessed the risk in patients with angina and non-obstructive coronary artery disease (ANOCA), excluding those with heart failure or organic stenosis of the coronary arteries. Furthermore, we analysed whether the risk of CMD differed according to component factors and sex. This study included 84 patients with ANOCA (36 men and 48 women; mean age, 63 years) who underwent coronary angiography and functional testing (CFT). The CFT included a spasm provocation test (SPT), followed by a coronary microvascular function test (CMVF). In the SPT, patients were mainly provoked by acetylcholine (ACh), and coronary spasm was defined as >90% transient coronary artery constriction on coronary angiography, accompanied by chest pain or ischaemic changes on electrocardiography. In 15 patients (18%) with negative ACh provocation, ergonovine maleate (EM) was administered as an additional provocative drug. In the CMVF, a pressure wire was inserted into the left anterior descending coronary artery using intravenous adenosine triphosphate, and the CFR and IMR were measured using previously described methods. A CFR < 2.0 or IMR ≥ 25 was indicative of CMD. The correlations between various laboratory indices and CMD and its components were investigated, and logistic regression analysis was performed, focusing on factors where p < 0.05. Of the 84 patients, a CFR < 2.0 was found in 22 (26%) and an IMR ≥ 25 in 40 (48%) patients, with CMD identified in 46 (55%) patients. CMD was correlated with smoking (p = 0.020) and the use of EM (p = 0.020). The factors that correlated with a CFR < 2.0 included the echocardiograph index E/e' (p = 0.013), which showed a weak but positive correlation with the CFR (r = 0.268, p = 0.013). Conversely, the factors correlated with an IMR ≥ 25 included RAS inhibitor usage (p = 0.018) and smoking (p = 0.042). Assessment of the risk of CMD according to sex revealed that smoking (p = 0.036) was the only factor associated with CMD in men, whereas the left ventricular mass index (p = 0.010) and low glycated haemoglobin levels (p = 0.012) were associated with CMD in women. Our results indicated that smoking status and EM use were associated with CMD. The risk of CMD differed between the two CMD components and sex. Although these factors should be considered when treating CMD, smoking cessation remains important. In addition, CMD assessment should be performed carefully when EM is used after ACh provocation. Further validation of our findings using prospective studies and large registries is warranted.

A novel degradable PEG superparamagnetic iron oxide capsule coupled with a polyphenolic nano-enzymatic conjugate (PSPM-NE), to treat ROS-driven cardiovascular-diseases, tested in atherosclerosis as a model disease, and hypothesizing autoimmunity as an atheroma's trigger.

Cardiovascular diseases account for a significant portion of the worldwide mortality rate. This aroused interest among the specialised scientific community, seeking for solutions based on non-clinical and clinical investigations, to shed light onto the physio-pathology of cardiovascular impairment. It is proven challenging managing chronic cardiovascular illnesses like atherosclerosis, arrhythmias, and diverse cardiomyopathies. In certain cases, there is no approved treatment. In other cases, the need for combining therapeutic components, when dealing with co-morbidities, may increase the risk of toxicity-driven cardiovascular impairment. In this case, because the risk of cardiac events correlates with the QT prolongation rates, the QT or QTc interval prolongation has become an important biomarker to access drug-related cardio-toxicity. Several approaches have been found in the current literature, aiming at improving physiological acceptance, i.e., to reduce toxicity. Nanotechnology has increasingly appeared as a promising ally to modulate active substances, preserving cardiovascular function and optimising drug effectiveness, i.e., acting as a cardio-protective mechanism, leveraging the effects of drug-driven cardio-toxicity. In this manuscript, the author combines plant active compounds and nanotechnological strategies, e.g., nano-encapsulation, nano-enzymes, magnetically driven nano-delivery systems, applied in regenerative medicine, and assesses their effects on the cardiovascular system, e.g., as cardio-protective factors, reducing cardio-toxicity. The aim is to propose a new strategy to tackle atherosclerosis initiation and progression, in a drug design that targets ROS-removal and reduces inflammation, using auto-immunity biomarkers to select key atheroma-related signalling cascades. To analyse physiological phenomena related to atherosclerosis initiation and progression, the author proposes both experimental observations and a new haemorheological computational model of arterial constriction. The results of such analysis are used as motivators in the design of the here presented strategy to tackle atheroma. This novel design is based on degradable polyethylene glycol (PEG) superparamagnetic iron oxide capsule coupled with a polyphenolic nano-enzymatic conjugate (PSPM-NE).

Phospholipase C-β3 is dispensable for vascular constriction but indispensable for vascular hyperplasia

Angiotensin II (AngII) induces the contraction and proliferation of vascular smooth muscle cells (VSMCs). AngII activates phospholipase C-β (PLC-β), thereby inducing Ca2+ mobilization as well as the production of reactive oxygen species (ROS). Since contraction is a unique property of contractile VSMCs, signaling cascades related to the proliferation of VSMCs may differ. However, the specific molecular mechanism that controls the contraction or proliferation of VSMCs remains unclear. AngII-induced ROS production, migration, and proliferation were suppressed by inhibiting PLC-β3, inositol trisphosphate (IP3) receptor, and NOX or by silencing PLC-β3 or NOX1 but not by NOX4. However, pharmacological inhibition or silencing of PLC-β3 or NOX did not affect AngII-induced VSMC contraction. Furthermore, the AngII-dependent constriction of mesenteric arteries isolated from PLC-β3∆SMC, NOX1−/−, NOX4−/− and normal control mice was similar. AngII-induced VSMC contraction and mesenteric artery constriction were blocked by inhibiting the L-type calcium channel Rho-associated kinase 2 (ROCK2) or myosin light chain kinase (MLCK). The activation of ROCK2 and MLCK was significantly induced in PLC-β3∆SMC mice, whereas the depletion of Ca2+ in the extracellular medium suppressed the AngII-induced activation of ROCK2, MLCK, and vasoconstriction. AngII-induced hypertension was significantly induced in NOX1−/− and PLC-β3∆SMC mice, whereas LCCA ligation-induced neointima formation was significantly suppressed in NOX1−/− and PLC-β3∆SMC mice. These results suggest that PLC-β3 is essential for vascular hyperplasia through NOX1-mediated ROS production but is nonessential for vascular constriction or blood pressure regulation.

Investigating the potential of catheter-assisted pulsed focused ultrasound ablation for atherosclerotic plaques.

Atherosclerosis is a condition in which an adhesive substance called plaque accumulates over time inside the arteries. Plaque buildup results in the constriction of arteries, causing a shortage of blood supply to tissues and organs. Removing atherosclerotic plaques controls the development of acute ischemic stroke and heart diseases. It remains imperative for positive patient outcomes. This study sought to develop a minimally invasive technique for removing arterial plaques by applying focused ultrasound (FUS) energy on the metal surface of a nitinol catheter wire to induce inertial cavitation. The induced cavitation can deplete plaque mechanically inside the arteries, leading towards improved recanalization of blood vessels. The enhanced cavitation effect induced by combining FUS with a metal catheter was first verified by exposing agar phantom gels with or without a 0.9-mm diameter nitinol wire to an acoustic field produced by a 0.5-MHz FUS transducer. The phenomenon was further confirmed in pork belly fat samples with or without a 3-mm diameter nitinol catheter wire. Cavitation was monitored by detecting the peaks of emitted ultrasound signals from the samples using a passive cavitation detector (PCD). Cavitation threshold values were determined by observing the jump in the peak amplitude of signals received by the PCD when the applied FUS peak negative pressure (PNP) increased. To simulate arterial plaque removal, FUS with or without a catheter was used to remove tissues from pork belly fat samples and the lipid cores of human atherosclerotic plaque samples using 2500-cycle FUS bursts at 10% duty cycle and a burst repetition rate of 20Hz. Treatment outcomes were quantified by subtracting the weight of samples before treatment from the weight of samples after treatment. All measurements were repeated 5 times (n=5) unless otherwise indicated, and paired t-tests were used to compare the means of two groups. A p-value of <0.05 will be considered significant. Our results showed that with a nitinol wire, the cavitation threshold in agar phantoms was reduced to 2.6MPa from 4.3MPa PNP when there was no nitinol wire in the focal region of FUS. For pork belly fat samples, cavitation threshold values were 1.0 and 2.0MPa PNP, with and without a catheter wire, respectively. Pork belly fat tissues and lipid cores of atherosclerotic plaques were depleted at the interface between a catheter and the samples at 2 and 4MPa FUS PNP, respectively. The results showed that with a catheter wire in the focal region of a 3-min FUS treatment session, 24.7 and 25.6mg of lipid tissues were removed from pork belly fat and human atherosclerotic samples, respectively. In contrast, the FUS-only group showed no reduction in sample weight. The differences between FUS-only and FUS-plus-catheter groups were statistically significant (p<0.001 for the treatment on pork belly samples, and p<0.01 for the treatment on human atherosclerotic samples). This study demonstrated the feasibility of catheter-assisted FUS therapy for removing atherosclerotic plaques.

Intramyocardial injection of hypoxia-conditioned extracellular vesicles increases myocardial perfusion in a swine model of chronic coronary disease

ObjectiveCoronary artery disease remains a leading cause of morbidity and mortality worldwide. Patients with advanced coronary artery disease who are not eligible for endovascular or surgical revascularization have limited options. Extracellular vesicles have shown potential to improve myocardial function in preclinical models. Extracellular vesicles can be conditioned to modify their components. Hypoxia-conditioned extracellular vesicles have demonstrated the ability to reduce infarct size and apoptosis in small animals. Our objective is to assess the potential benefits of hypoxia-conditioned extracellular vesicles in a large animal model of coronary artery disease. MethodsCoronary artery disease was induced in 14 Yorkshire swine by ameroid constriction of the left circumflex coronary artery. Two weeks postsurgery, swine underwent a repeat left thoracotomy for injections of hypoxia-conditioned extracellular vesicles (n = 7) or saline (control, n = 7). Five weeks later, all animals underwent terminal harvest for perfusion measurements and myocardial sectioning. ResultsMyocardial perfusion analysis demonstrated a trend toward increase at rest and a significant increase during rapid pacing (P = .09, P < .001). There were significant increases in activated phosphorylated endothelial nitric oxide synthase, endothelial nitric oxide synthase, phosphatidylinositol 3-kinase, phosphorylated protein kinase B, and the phosphorylated protein kinase B/protein kinase B ratio in the hypoxia-conditioned extracellular vesicles group compared with the control group (all P < .05). Additionally, there was a significant decrease in the antiangiogenic proteins collagen 18 and angiostatin (P = .01, P = .01) in the hypoxia-conditioned extracellular vesicles group. ConclusionsIntramyocardial injection of hypoxia-conditioned extracellular vesicles results in increased myocardial perfusion without a corresponding change in vessel density. Therefore, this improvement in perfusion is possibly due to changes in nitric oxide signaling. Hypoxia-conditioned extracellular vesicles represent a potential therapeutic strategy to increase myocardial perfusion in patients with advanced coronary artery disease.