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To assess endothelial dysfunction in young men (aged 30-50) with vasculogenic ED identified through penile Doppler ultrasound. To evaluate changes in endothelial function using EndoPAT before and 3-6 months after daily low-dose phosphodiesterase type 5 (PDE5) inhibitor therapy. To investigate endothelial function alterations in hypogonadal patients before and 3-6 months after initiating testosterone (T) therapy
This double-blind placebo-controlled parallel group randomized study design will be used to test whether 4 weeks of atorvastatin 10 mg daily reduces levels of inflammatory markers in OSA patients treated with CPAP (standard of care). The purpose of this study is to investigate: 1) whether statins reduce endothelial inflammation and pro-thrombotic conditions in OSA, including in patients adherent to CPAP (Aim 1); and 2) whether statins reduce endothelial inflammation and pro-thrombotic conditions by improving endothelial cholesterol metabolism and trafficking in OSA (Aim 2).
Very little is understood about the off-target vascular mechanisms of anti-cancer drug toxicity and the impact of exercise on these changes. Much of what has been learned about molecular pathways regulating vascular endothelial function has been established by logical expansion of knowledge obtained through experimental studies (e.g., discovery of endothelium-derived relaxing factor/nitric oxide). Within the last 10 years technological advancements of -omics approaches, such as RNA-sequencing and shotgun proteomics, have dramatically reduced the cost and technical challenge of accessing these tools for discovery-based research. Investigators are now able to obtain unbiased datasets showing changes in transcript or protein expression within complex samples. With cost and accessibility of sequencing is no longer being substantial bottleneck, one of major challenges researchers now face is determining how to meaningfully interpret profiles from large datasets. The extensive characterization of molecular pathways impacting inflammatory responses, endothelial function and angiogenesis, the pathway and network analysis tools will be an asset for identification molecular pathways relevant to alterations in microvascular endothelial function. The investigators preliminary studies on only a small number of samples highlights this potential of the proposed approach to lead to identify personalized medicine-based profiles that will predict patients are likely to develop microvascular endothelial dysfunction from CTx.
The development of type II diabetes (T2D) is strongly associated with obesity and both are well-established risk factors for cardiovascular disease. Knowing that vascular dysfunction is an early event in the development of cardiovascular disease in obese diabetic (OB-T2D) patients, The investigators set their long-term goal to define molecular mechanisms of vascular dysfunction and corrective strategies that target these mechanisms such as physical activity and weight loss. The investigators recently discovered that human adipose tissues release extracellular vesicles (adiposomes) that are efficiently captured by endothelial cells. Adiposomes are known to carry bioactive cargos such as proteins and micro RNAs; however, their lipid content has not been studied nor has their ability to transfer their lipid cargo to endothelial cells. In the current application, the investigators propose to investigate the role of adiposomes in communicating the unhealthy milieu, mainly dysregulated lipids, to endothelial cells in OB-T2D subjects. On top of these lipid species that the investigators propose to be carried by adiposomes are glycosphingolipids (GSLs). These lipids originate from the glycosylation of ceramides, a chemical process that is upregulated in the presence of inflammation and high glucose levels. Preliminary findings showed that in endothelial cells, GSL-rich adiposomes disturb plasma membrane structure and subsequently induce endothelial dysfunction. Moreover, the investigators found that preconditioning endothelial cells with high shear stress (which is an exercise mimetic) protected endothelial cells from the detrimental effects induced by adiposomes. Therefore, the central hypothesis is that adipose tissues in OB-T2D patients release GSL-loaded adiposomes that induce vascular endothelial dysfunction. The researchers propose that exercise and weight loss interventions (bariatric surgery) will restore adipose tissue homeostasis, reduce GSL-loaded adiposomes, and subsequently alleviate vascular risk in OB-T2D patients. The investigators will test the hypotheses by pursuing the following aims: aim 1: Investigate the role of GSL-rich adiposomes in the pathogenesis of endothelial dysfunction in OB-T2D adults; aim 2: Test the effectiveness of exercise training in reducing adiposome-mediated effects on vascular function; and aim 3: Examine changes in adiposome/caveolae axis following metabolic surgery and their association with vascular function.
This is a prospective international multi-center registry and biorepository trial of children and adolescents/young adults (AYA) undergoing hematopoietic cell transplantation (HCT) to assess the impact of endotheliopathies in the HCT setting as a contributor of significant morbidity and mortality.
Specific Aim 1: To test the hypothesis that prolonged (3-month) treatment with galantamine inhibits NADPH IsoLG-protein adducts formation and improves markers of endothelial cell (EC) dysfunction in AAs. Aim 1a: The investigators will determine if galantamine inhibits NADPH IsoLG-protein adducts formation, superoxide production, and immune cell activation compared to placebo. For this purpose, the investigators will study peripheral blood mononuclear cell (PBMC), a critical source of systemic oxidative stress, collected from study participants. Aim 1b: The investigators will determine if galantamine reduces intracellular Iso-LGs, ICAM-1, and 3-nitrotyrosine, a marker of vascular oxidative stress, in ECs harvested from study participants. Specific Aim 2: To determine if prolonged (3-month) treatment with galantamine improves endothelial dysfunction as measured by vascular reactivity in AAs. The investigators will measure vascular reactivity in response to ischemia in two vascular beds: (a) in conduit arteries (brachial artery) using brachial artery diameter flow-mediated dilation (FMD), and (b) in the microvasculature (MBV) using contrast-enhanced ultrasonography in skeletal muscle. Sub-study (optional) Will study the effect of trans-auricular vagus nerve stimulation (TaVNS) during a period of enhanced vascular oxidative stress This proposal will study a novel mechanism that could alter the oxidative and immunogenic responses that contributes to endothelial dysfunction in AAs and will offer a potential pathway for the development of more effective therapies aimed at decreasing the progression of endothelial dysfunction to cardiovascular disease in this population.
The goal of this mechanistic clinical trial is to learn about the effects of medications called soluble guanylyl cyclase stimulators on vascular function and markers of kidney and brain injury in patients having heart surgery. The main questions it aims to answer are: 1. Does soluble guanylyl cyclase stimulation improve blood vessel function compared to placebo? 2. Does soluble guanylyl cyclase stimulation decrease markers of kidney injury and brain injury compared to placebo? Participants will be randomized to a soluble guanylyl cyclase stimulator called vericiguat or placebo, and researchers will compare vascular function and markers of brain and kidney injury to see if vericiguat improves vascular function and reduces markers of injury. This will provide important information to determine the underlying reasons that patients have some kidney and brain function problems after having heart surgery.
The proposed mechanistic trial will test the effect of dietary sodium reduction on cardiac and vascular structure and function in those with elevated blood pressure or hypertension. Findings from this study will fill the knowledge gap on the underlying mechanisms of dietary sodium intake on cardiovascular disease risk in addition to blood pressure and could provide further evidence on sodium reduction for the prevention of cardiovascular disease.
Cardiopulmonary bypass during cardiac surgery provides blood flow to the body during surgery but has adverse effects on different organs. Blood flow during cardiopulmonary bypass may be pulsatile or non-pulsatile, which may impact normal organ function after surgery. The study will collect data on the type of cardiopulmonary bypass used during surgery and organ function to determine if there is an association between the type of bypass and organ function.
Background: This study is designed to provide samples to help us study the genes your blood cells are making as well as the proteins, sugars, fats, vitamins and other metabolites found in your blood or urine. Blood samples may also be collected to make special cells. These are called induced pluripotent stem cells or iPSCs. Pluripotent stem cells are cells that can be converted into any type of cell. Researchers want to study in the lab iPSCs that are derived from blood samples. Objective: To collect samples to help study genes, proteins, sugars, fats, vitamins, and other metabolites found in blood or urine. Eligibility: Healthy volunteers and patients ages 18 and older Design: First-time research study participants at NIH will have an initial visit for this study that should last no more than 1 hour. All other visits should last 20 30 minutes. Participants will undergo a limited history and physical exam. Participants may have routine blood and urine tests. If participants are giving a blood sample, they must have a hemoglobin level checked in the past 12 months to make sure it is safe for them to give a blood sample for research. Participants may have a venous blood collection. They may do this at several visits. They will lie on a recliner or couch or sit in a chair. A needle will be placed into a vein in the hand or arm, using sterile techniques. Blood will be withdrawn into multiple syringes or tubes. Participants may be asked to provide urine in an appropriate container...