endothelin-1 and Vasculitis

Aldosterone exerts direct effects on the vascular system by inducing oxidative stress, inflammation, hypertrophic remodeling, fibrosis, and endothelial dysfunction. Aldosterone exerts its effects through genomic and nongenomic pathways in a mineralocorticoid receptor (MR)-dependent or independent manner. Other aldosterone receptors such as GPR30 have been identified. A tight relation exists between the aldosterone and angiotensin II pathways, as well as with the endothelin-1 system. There is a correlation between plasma levels of aldosterone and cardiovascular risk. Recently, an increasing body of evidence has underlined the importance of aldosterone in cardiovascular complications associated with the metabolic syndrome, such as arterial remodeling and endothelial dysfunction. Blockade of MR is an increasingly used evidence-based therapy for many forms of cardiovascular disease, including hypertension, heart failure, chronic kidney disease, and diabetes mellitus.

Topics: Adipocytes; Aldosterone; Angiotensin II; Animals; Antihypertensive Agents; Blood Vessels; Cardiovascular Diseases; Endothelin A Receptor Antagonists; Endothelin-1; Endothelium, Vascular; Fibrosis; Gene Expression Regulation; Humans; Hypertension; Hypertrophy; Metabolic Syndrome; Mineralocorticoid Receptor Antagonists; Mineralocorticoids; Muscle, Smooth, Vascular; Oxidative Stress; Receptor, Endothelin A; Receptors, Mineralocorticoid; Renin-Angiotensin System; Signal Transduction; Sodium; Vasculitis; Vasoconstriction

Endogenous endothelin-1-dependent (ET-1) tone in coronary arteries depends on the balance between ET(A) and ET(B) receptor-mediated effects and on parameters such as receptor distribution and endothelial integrity. Numerous studies highlight the striking functional interactions that exist between nitric oxide (NO) and ET-1 in the regulation of vascular tone. Many of the cardiovascular complications associated with cardiovascular risk factors and aging are initially attributable, at least in part, to endothelial dysfunction characterized by a dysregulation between NO and ET-1. The contribution of the imbalance between smooth muscle ET(A/B) and endothelial ET(B) receptors to this process is poorly understood. An increased contribution of ET-1 that is associated with a proportional decrease in that of NO accompanies the development of coronary endothelial dysfunction, coronary vasospasm, and atherosclerosis. These data form the basis for the rationale of testing therapeutic approaches counteracting ET-1-induced cardiovascular dysfunction. It remains to be determined whether the beneficial role of endothelial ET(B) receptors declines with age and risk factors for cardiovascular diseases, revealing smooth muscle ET(B) receptors with proconstricting and proinflammatory activities.

Topics: Animals; Blood Pressure; Coronary Artery Disease; Coronary Circulation; Coronary Vessels; Endothelin-1; Humans; Receptors, Endothelin; Risk Factors; Stress, Mechanical; Vasculitis

Vascular damage caused by cerebral ischemia leads to edema, hemorrhage formation, and worsened outcomes in ischemic stroke patients. Therapeutic interventions need to be developed to provide vascular protection. The purpose of this review is to identify the pathophysiologic processes involved in vascular damage after ischemia, which may lead to strategies to provide vascular protection in ischemic stroke patients.. The pathologic processes caused by vascular injury after an occlusion of a cerebral artery can be separated into acute (hours), subacute (hours to days), and chronic (days to months). Targets for intervention can be identified for all 3 stages. Acutely, superoxide is the predominant mediator, followed by inflammatory mediators and proteases subacutely. In the chronic phase, proapoptotic gene products have been implicated.. Pharmacological agents designed to target specific pathologic and protective processes affecting the vasculature should be used in clinical trials of vascular protection after acute ischemic stroke.

Topics: Acute Disease; Angiopoietins; Angiotensin II; Antioxidants; Apoptosis; Blood-Brain Barrier; Brain Edema; Brain Ischemia; Cerebral Arteries; Cerebral Hemorrhage; Chronic Disease; Endothelin-1; Endothelium, Vascular; Humans; Inflammation Mediators; Matrix Metalloproteinases; Neuroprotective Agents; Neutrophils; Oxidative Stress; Reactive Oxygen Species; Vascular Endothelial Growth Factor A; Vasculitis

Angiotensin (Ang) II and endothelin (ET-1) can both be regulated by NF-kappaB. They are, to variable degrees, also capable of activating NF-kappaB and increase the expression of NF-kappaB-dependent genes. Ang II-related vascular effects are in part mediated by ET-1. Nitric oxide synthase inhibition facilitates Ang II-related effects, which can be inhibited both by AT1-receptor blockers and by endothelin system inhibitors. This state-of-affairs supports the notion that a combined therapeutic strategy of inhibiting Ang II and ET-1 generation or blocking their effects at the receptor level would be superior to either strategy alone. Animal studies are encouraging but not without conflicting results. Angiotensin-converting enzyme inhibitors and AT1-receptor blockers have a superb track record in experimental animal models and in a host of clinical studies. Selective and nonselective blockers of the ET-1 receptors are important research tools and are also undergoing clinical trials. Inhibitors of the endothelin-converting enzyme have been developed. The recent elucidation of the endothelin-converting enzyme's physical structure should facilitate the development of still more novel compounds to inhibit ET-1 generation. We have recently engendered supportive evidence in this regard.

Topics: Angiotensin II; Animals; Endothelin-1; Gene Expression Regulation; Humans; Hypertension; NF-kappa B; Vasculitis

Although anti-HLA antibodies (Abs) cause most antibody-mediated rejections of renal allografts, non-anti-HLA Abs have also been postulated to contribute. A better understanding of such Abs in rejection is needed.. We conducted a nationwide study to identify kidney transplant recipients without anti-HLA donor-specific Abs who experienced acute graft dysfunction within 3 months after transplantation and showed evidence of microvascular injury, called acute microvascular rejection (AMVR). We developed a crossmatch assay to assess serum reactivity to human microvascular endothelial cells, and used a combination of transcriptomic and proteomic approaches to identify non-HLA Abs.. We identified a highly selected cohort of 38 patients with early acute AMVR. Biopsy specimens revealed intense microvascular inflammation and the presence of vasculitis (in 60.5%), interstitial hemorrhages (31.6%), or thrombotic microangiopathy (15.8%). Serum samples collected at the time of transplant showed that previously proposed anti-endothelial cell Abs-angiotensin type 1 receptor (AT1R), endothelin-1 type A and natural polyreactive Abs-did not increase significantly among patients with AMVR compared with a control group of stable kidney transplant recipients. However, 26% of the tested AMVR samples were positive for AT1R Abs when a threshold of 10 IU/ml was used. The crossmatch assay identified a common IgG response that was specifically directed against constitutively expressed antigens of microvascular glomerular cells in patients with AMVR. Transcriptomic and proteomic analyses identified new targets of non-HLA Abs, with little redundancy among individuals.. Our findings indicate that preformed IgG Abs targeting non-HLA antigens expressed on glomerular endothelial cells are associated with early AMVR, and that

Topics: Acute Disease; Adult; Aged; Endothelial Cells; Endothelin-1; Female; Graft Rejection; Hemorrhage; Humans; Immunoglobulin G; Kidney Glomerulus; Kidney Transplantation; Male; Microvessels; Middle Aged; Receptor, Angiotensin, Type 1; Thrombotic Microangiopathies; Time Factors; Vasculitis

The extracellular matrix (ECM) is a dynamic, bioactive structure critical to organ development, structure and function. Excessive remodeling of the ECM is a hallmark of a variety of inflammatory conditions including vascular disease. Endothelin-1 (ET1) synthesis is understood to promote cardiovascular diseases including acute cardiac transplant rejection; however, the contribution of ECM-derived chemokines (matrikines) to vascular inflammation remains poorly understood. Herein we report that the matrikine acetylated Pro-Gly-Pro (PGP) stimulates vascular inflammation through activation of endothelial CXC Chemokine Receptor 2 (CXCR2) and production of endothelin-1 both in vitro and in vivo. As a proof of hypothesis, we demonstrate that coronary PGP levels associate with both circulating endothelin-1 and acute rejection in cardiac transplant patients (sensitivity of 100% and specificity of 86%). These findings establish PGP as a novel mediator in cardiovascular disease, and implicate bioactive matrix fragments as underappreciated agents potentially active in numerous conditions propagated by progressive vascular inflammation.

Topics: Adult; Chemokines; Endothelin-1; Extracellular Matrix; Female; Graft Rejection; Heart Transplantation; Humans; Male; Middle Aged; Oligopeptides; Proline; Receptors, Interleukin-8B; Vasculitis

Cardiovascular diseases are the leading cause of morbidity and mortality in the world. Aging is associated with an increased incidence of cardiovascular disease. Premenopausal women are relatively protected from vascular alterations compared with age-matched men, likely due to higher levels of the female sex hormones. However, these vasoprotective effects in women are attenuated after menopause. Thus, the vascular system in aging women is affected by both the aging process as well as loss of hormonal protection, positioning women of this age group at a high risk for cardiovascular diseases such as hypertension, myocardial infarction, and stroke. The endothelin system in general and endothelin-1 (ET-1) in particular plays an important role in the pathogenesis of vascular dysfunction associated with aging. Evidence suggests that the female sex steroids can interfere with the vascular expression and actions of ET-1 via several mechanisms, which may further contribute to pathological processes in the vasculature of aging women. In this review, we have summarized hormone-dependent vascular pathways whereby ET-1 may mediate the deleterious effects of aging in postmenopausal females.

Topics: Aged; Aging; Animals; Cardiovascular Diseases; Endothelin-1; Estrogens; Female; Humans; Vasculitis; Vasoconstriction

We previously showed that in transgenic mice with endothelium-targeted overexpression of human preproendothelin-1, mesenteric resistance arteries exhibited vascular remodeling, endothelial dysfunction and increased oxidative stress early in life in the absence of significant elevation of blood pressure. To further characterize this model, the role of vascular inflammation was investigated in young male transgenic and wild-type littermate mice.. Systemic and local inflammatory markers in mesenteric arteries were assessed by Luminex-based enzyme-linked immunosorbent assay technique, confocal microscopy, electrophoretic mobility shift assay and western blotting in 10-week old male transgenic and wild-type mice. Although no differences were found for systemic inflammatory markers, vascular staining for monocyte chemoattractant protein-1 and macrophage infiltration were significantly increased (P < 0.05) in transgenic mice compared with wild-type littermates. Transgenic mice exhibited significant increase (P < 0.01) in the activation of transcription factors activator protein-1 and nuclear factor kappa B compared with wild-type littermates. Western blotting analysis showed significantly increased (P < 0.05) blood vessel wall expression of vascular cell adhesion molecule-1 in transgenic mice.. These findings suggest that in this murine model of endothelial cell-restricted preproendothelin-1 overexpression, endothelin-1 induces vascular inflammation by multiple pathways in young animals in the absence of blood pressure elevation or systemic inflammation.

Topics: Animals; Blood Pressure; Endothelial Cells; Endothelin-1; Humans; Male; Mice; Vasculitis

Deoxycorticosterone acetate (DOCA)-salt hypertension has an important endothelin-1 (ET-1)-dependent component. ET-1-induced vascular damage may be mediated in part by oxidative stress and vascular inflammation. Homozygous osteopetrotic (Op/Op) mice, deficient in macrophage colony-stimulating factor (m-CSF), exhibit reduced inflammation. We investigated in osteopetrotic (Op/Op) mice the effects of DOCA-salt hypertension on vascular structure, function, and oxidative stress, the latter as manifested by reduced nicotinamide adenine dinucleotide phosphate [NAD(P)H] oxidase activity. Mice were implanted with DOCA (200 mg/mouse, under 5% isofluorane anesthesia) and given saline for 14 days. Systolic blood pressure (mmHg) was significantly increased (146 +/- 2 and 138 +/- 1; P < 0.001 vs. basal 115 +/- 3 and 115 +/- 3, respectively) by DOCA-salt in wild-type (+/+) and heterozygous (Op/+) mice, but not in Op/Op mice (130 +/- 1 vs. basal 125 +/- 3). Norepinephrine contractile response was significantly enhanced, while acetylcholine endothelium-dependent vasodilation was significantly impaired in DOCA-salt-treated +/+ and Op/+ mice compared with control mice. No changes in norepinephrine-induced contraction and acetylcholine-induced relaxation were observed in DOCA-salt Op/Op mice. DOCA-salt +/+ and Op/+ mice had significantly increased mesenteric resistance artery media-to-lumen ratio and media cross-sectional area, neither of which were altered in Op/Op mice. Basal vascular superoxide production and NAD(P)H oxidase activity, vascular cell adhesion molecule-1 expression, and macrophage infiltration were significantly increased only in DOCA-salt +/+ mice. Thus m-CSF-deficient mice developed less endothelial dysfunction, vascular remodeling, and oxidative stress induced by DOCA-salt than +/+ and Op/+ mice, suggesting that inflammation may play a role in DOCA-salt hypertension, a model that results in part from effects of ET-1, which has proinflammatory actions.

Topics: Animals; Biomarkers; Desoxycorticosterone; Disease Models, Animal; Endothelin-1; Endothelium, Vascular; Hypertension; Macrophage Colony-Stimulating Factor; Macrophages; Mesenteric Arteries; Mice; Mice, Inbred Strains; Mice, Mutant Strains; Osteopetrosis; Reactive Oxygen Species; Superoxides; Vascular Resistance; Vasculitis

The vasoactive peptide endothelin-1 (ET-1) may contribute to the pathogenesis of atherosclerosis and its acute complications. Because inflammation of the vessel wall is a characteristic feature of atherosclerosis, this study investigated the effect of ET-1 on the proinflammatory transcription factor NF-kappaB in monocytes. Monocyte/macrophages are a major source of inflammatory mediators in atheroma and are located in rupture prone plaque areas. In human monocytes ET-1 caused NF-kappaB activation. Specificity of ET-1-induced NF-kappaB activation was ascertained by supershift and competition experiments. This ET-1 effect was blocked by the ET-A-receptor antagonist BQ-123 but not by the ET-B-receptor antagonist BQ-788. PI-1, a specific inhibitor of the IkappaB-alpha-degrading proteasome complex, also prevented NF-kappaB activation. ET-1 stimulated expression of the proinflammatory molecule CD40 but not of the cytokine IL-6 in a NF-kappaB-dependent manner.. The data demonstrate the ability of ET-1 to activate inflammatory pathways in human monocytes differentially.

Topics: Antihypertensive Agents; CD40 Antigens; Cells, Cultured; Endothelin-1; Humans; Interleukin-6; Monocytes; NF-kappa B; Oligopeptides; Peptides, Cyclic; Piperidines; Vasculitis

The relative contributions of microvascular inflammation and vasomotor dysregulation to the development of acute vaso-occlusive crisis in sickle cell disease have been intensely studied. The present observational study was designed to examine the levels of circulating proinflammatory cytokines, anti-inflammatory cytokines, and vasoactive mediators during and after acute painful crisis. In symptomatic sickle cell patients, plasma levels of endothelin-1 and prostaglandin E2 were elevated during crises compared with healthy African-American controls. These levels had decreased, but not normalized, when patients were seen 1 to 3 weeks after discharge from hospital. Other mediators (tumor necrosis factor alpha [TNFalpha], interleukin-1beta [IL-1beta], IL-6, IL-8, and IL-10) were neither elevated in asymptomatic sickle cell disease nor in acute vaso-occlusive crisis. As a potent long-acting mediator of vasoconstriction and inflammation, endothelin-1 may play a key role in the cycle of ischemia and inflammation that initiates and sustains pain of crisis. The downregulatory effects of prostaglandin E2 on immune cell function may contribute to the increased susceptibility to infection observed in patients with sickle cell disease.

Topics: Acute Disease; Adult; Anemia, Sickle Cell; Cell Adhesion Molecules; Cytokines; Dinoprostone; Endothelin-1; Humans; Ischemia; Microcirculation; Middle Aged; Monocytes; Pain; Vascular Diseases; Vasculitis; Vasoconstriction

The combined effects of hypoxia and interleukin 1, lipopolysaccharide, or tumor necrosis factor alpha on the expression of genes encoding endothelial constitutive and inducible nitric oxide synthases, endothelin 1, interleukin 6, and interleukin 8 were investigated in human primary pulmonary endothelial cells and whole pulmonary artery organoid cultures. Hypoxia decreased the expression of constitutive endothelial nitric oxide synthase (NOS-3) mRNA and NOS-3 protein as compared with normoxic conditions. The inhibition of expression of NOS-3 corresponded with a reduced production of NO. A combination of hypoxia with bacterial lipopolysaccharide, interleukin 1 beta, or tumor necrosis factor alpha augmented both effects. In contrast, the combination of hypoxia and the inflammatory mediators superinduced the expression of endothelin 1, interleukin 6, and interleukin 8. Here, we have shown that inflammatory mediators aggravate the effect of hypoxia on the down-regulation of NOS-3 and increase the expression of proinflammatory cytokines in human pulmonary endothelial cells and whole pulmonary artery organoid cultures.

Topics: Blotting, Northern; Blotting, Western; Cell Hypoxia; Endothelin-1; Endothelium, Vascular; Enzyme Induction; Gene Expression Regulation, Enzymologic; Humans; Hypertension, Pulmonary; Interleukin-1; Interleukin-6; Interleukin-8; Isoenzymes; Lipopolysaccharides; Nitric Oxide; Nitric Oxide Synthase; Pulmonary Artery; RNA, Messenger; Vasculitis