endothelin-1 and Diabetes-Mellitus

Diabetic kidney disease (DKD) is one of the common complications of diabetes mellitus, which usually progresses to end-stage renal disease and causes great damage to the health of patients. Endothelin-1 (ET-1), a molecule closely associated with the progression of DKD, has increased expression in response to high glucose stimulation and is involved in hemodynamic changes, inflammation, glomerular and tubular dysfunction in the kidney, causing an increase in proteinuria and a decrease in glomerular filtration function, ultimately leading to glomerulosclerosis and renal failure. This paper aims to review the molecular level changes, regulatory mechanisms, and mechanisms of action of ET-1 under DKD, clinical trials of ET-1 receptor antagonists in recent years and current problems, to provide basic information and new research directions and ideas for the treatment of DKD and ET-1-related research.

Topics: Diabetes Mellitus; Diabetic Nephropathies; Endothelin-1; Humans; Kidney; Kidney Glomerulus; Podocytes

There is substantial research on the vasoactive peptide endothelin (ET)-1 in physiology, as well as in pathology. In fact, pathologically elevated levels of ET-1 have been found in several disease states, such as various cardiovascular diseases, different cancers, some neurodegenerative disorders, as well as in diabetes. Here, we describe and discuss ET-1, its importance in different diseases, and the potential therapeutic effects of ET-traps in the treatment of these diseases. Previous in vitro and in vivo research (in the diabetes disease space) demonstrated that ET-traps potently and significantly prevent the induction of different markers of diabetes-related pathology. This included induction of extracellular matrix (ECM) proteins (collagen 4α1 and fibronectin), which are pathologically elevated in diabetes. The ET-traps prevented induction of these and brought a significant return to non-diabetic levels. We also discuss the merits of using ET-traps over the currently used endothelin receptor antagonists (ERAs) and previously used therapeutic antibodies.

Topics: Cardiovascular Diseases; Diabetes Mellitus; Endothelin Receptor Antagonists; Endothelin-1; Female; Humans; Neurodegenerative Diseases; Pregnancy; Pregnancy Complications; Receptors, Endothelin

The discovery of endothelin (ET) in 1988 has led to considerable effort to unravel its implication in health and disease and the mechanisms evoked by ET. ET-1 and related signaling aberrancies are believed to be implicated in the pathogenesis of diverse cardiovascular diseases, such as hypertension, atherosclerosis, hypertrophy and diabetes. The endothelin system consists of three potent vasoconstrictive isopeptides, ET-1, ET-2 and ET-3, signaling through two G protein coupled receptors, ETA and ETB, which are linked to multiple signaling pathways. Activated signaling transduction pathways include the modulation of the adenylyl cyclase/cAMP pathway through stimulatory (Gs) and inhibitory (Gi) G proteins, activation of the phosphoinositide pathway through the activation of proteins Gq/11, generation of oxidative stress, growth factor receptor-related mitogenic events, such as the activation of phosphatidylinositol-3 kinase pathway, phosphoinositide pathway and activation of the mitogen-activated protein (MAP) kinase cascade. The levels of ETA and ETB receptors as well as the signaling pathways activated by these receptors are altered in several cardiovascular diseases including hypertension, hypertrophy, atherosclerosis, diabetes, etc. In this review, we provide an overview of the signaling events modulated by ET-1 in vascular smooth muscle cells in both physiological and pathological conditions.

Topics: Adenylyl Cyclases; Animals; Atherosclerosis; Calcium; Diabetes Mellitus; Endothelin-1; Humans; Hypertension; MAP Kinase Signaling System; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Oxidative Stress; Receptor, Endothelin A; Receptor, Endothelin B; Signal Transduction

The accumulation of unfolded proteins in the endoplasmic reticulum (ER) represents a cellular stress induced by multiple stimuli and pathologic conditions. Recent evidence implicates endothelin-1 (ET-1) in the induction of placental ER stress in pregnancy disorders. ER stress has previously also been implicated in various other disease states, including neurodegenerative disorders, diabetes, and cardiovascular diseases, as has ET-1 in the pathophysiology of these conditions. However, to date, there has been no investigation of the link between ET-1 and the induction of ER stress in these disease states. Based on recent evidence and mechanistic insight into the role of ET-1 in the induction of placental ER stress, the following review attempts to outline the broader implications of ET-1-induced ER stress, as well as strategies for therapeutic intervention based around ET-1.

Topics: Animals; Cardiovascular Diseases; Diabetes Mellitus; Disease; Endoplasmic Reticulum Stress; Endothelin Receptor Antagonists; Endothelin-1; Female; Humans; Nerve Degeneration; Pregnancy; Pregnancy Complications

Diabetes is not only an endocrine but also a vascular disease. Cardiovascular complications are the leading cause of morbidity and mortality associated with diabetes. Diabetes affects both large and small vessels and hence diabetic complications are broadly classified as microvascular (retinopathy, nephropathy and neuropathy) and macrovascular (heart disease, stroke and peripheral arterial disease) complications. Endothelial dysfunction, defined as an imbalance of endothelium-derived vasoconstrictor and vasodilator substances, is a common denominator in the pathogenesis and progression of both macro and microvascular complications. While the pathophysiology of diabetic complications is complex, endothelin-1 (ET-1), a potent vasoconstrictor with proliferative, profibrotic, and proinflammatory properties, may contribute to many facets of diabetic vascular disease. This review will focus on the effects of ET-1 on function and structure of microvessels (retina, skin and mesenteric arteries) and macrovessels (coronary and cerebral arteries) and also discuss the relative role(s) of endothelin A (ET(A)) and ET(B) receptors in mediating ET-1 actions.

Topics: Animals; Diabetes Complications; Diabetes Mellitus; Diabetic Angiopathies; Endothelin-1; Humans; Microvessels; Rats

Diabetes mellitus is a common disease and contributes to a high degree of morbidity and mortality. Cardiovascular complications, including diabetic cardiomyopathy are major causes of morbidity and mortality in diabetic patients. Diabetic cardiomyopathy is a condition that affects the myocardium, primarily. It is not necessarily associated with ischemic heart disease, high blood pressure, valvular or congenital anomalies. The pathology of diabetic cardiomyopathy includes interstitial fibrosis, apoptosis of cardiomyocytes, abnormal energy utilization, small vessel disease and cardiac neuropathy. These pathologies are induced by hyperglycemia and oxidative stress. Biochemical as well as electrolyte changes, especially reduced calcium availability also occurs in the myocardium of diabetic patients. The abnormal structure and biochemistry of the myocardium result in functional problems such as diastolic and systolic dysfunctions, which may cause symptoms of dyspnea and inability to tolerate exercise. No single specific therapeutic agent can treat diabetic cardiomyopathy because once the disease is overt, the management may require a variety of approaches such as risk factors and lifestyle modification, glucose control (insulin, alpha glucosidase inhibitors, sulfonylureas, biguanides, meglitinides, thiazolidinediones and dipeptidyl peptidase 4 (DPP-4) inhibitors); hormones (IGF-1); ACE inhibitors (captopril, enalapril); angiotensin II receptor antagonists (losartan, olmesartan); beta adrenoreceptor antagonists (acebutolol, carvedilol); peptides (adrenomedullin); endothelin-1 receptor antagonists (bosentan, tezosentan); calcium channel blockers (amlodipine, verapamil); antioxidants (methalothionein, alpha tocopherol, alpha lipoic acid) and antihyperlipidemic drugs (simvastatin, fenofibrate, ezetimibe) to effectively treat patients with diabetic cardiomyopathy.

Topics: Adrenergic beta-Antagonists; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Calcium Channel Blockers; Cardiomyopathies; Diabetes Complications; Diabetes Mellitus; Endothelin-1; Fenofibrate; Humans; Hypoglycemic Agents; Peroxisome Proliferator-Activated Receptors; Receptors, Angiotensin

Heart disease is among the leading causes of death in all populations. Cardiac dysfunctions are major complications in patients with advanced viral or bacterial infection, severe trauma and burns accompanied with multiple organ failure - collectively known as systemic inflammatory response syndrome (SIRS). SIRS, which is often subsequent to sepsis, is clinically featured by hypotension, tachypnea, hypo- or hyperthermia, leukocytosis and myocardial dysfunction. The striking association between inflammation and cardiac dysfunction not only prognoses likelihood of survival in patients with SIRS but also prompts the necessity of understanding the pathophysiology of cardiac dysfunction in SIRS, so that effective therapeutic regimen may be identified. Compelling evidence has shown significant and independent link among inflammation, sepsis, insulin resistance and cardiac dysfunction. Several cytokine signaling molecules have been speculated to play important roles in the onset of cardiac dysfunction under SIRS including endothelin-1 and toll-like receptor. Involvement of these pathways in cardiac dysfunction has been convincingly validated with transgenic studies. Nevertheless, the precise mechanism of action underscoring inflammation-induced cardiac contractile dysfunction is far from being clear. Given the substantial impact of inflammation and SIRS on health care, ecosystems and national economy, it is imperative to understand the cellular mechanisms responsible for cardiac contractile dysfunction under inflammation and sepsis so that new and effective therapeutic strategy against such devastating heart problems may be developed.

Topics: Animals; Biopterins; Cytokines; Diabetes Mellitus; Endothelin-1; Heart Diseases; Humans; Inflammation; Insulin Resistance; Myocardium; Nitric Oxide; Sepsis; Shock, Septic; Systemic Inflammatory Response Syndrome; Toll-Like Receptors

Topics: Angiotensin II; Arteriosclerosis; Cardiovascular Diseases; Cell Adhesion Molecules; Coagulants; Diabetes Mellitus; Endothelin-1; Endothelium, Vascular; Female; Humans; Pre-Eclampsia; Pregnancy; Vasoconstrictor Agents; Vasodilator Agents

The importance of signaling pathways in penile smooth muscles involved in normal erection and erectile dysfunction (ED) is discussed based on a review of the literature.. Erection is basically a spinal reflex that can be initiated by recruitment of penile afferents but also by visual, olfactory and imaginary stimuli. The generated nervous signals will influence the balance between the contractant and relaxant factors, which control the degree of contraction of penile smooth muscles and, thus, determine the functional state of the penis. The different steps involved in neurotransmission, impulse propagation and intracellular transduction of neural signals may be changed in different types of erectile dysfunction.. Recent findings have suggested an important role for RhoA/Rho kinase in the regulation of cavernosal smooth muscle tone and that changes in this pathway may contribute to ED in various patient subgroups, eg diabetes and vascular disease. Neurogenic nitric oxide is still considered the most important factor for immediate relaxation of penile vessels and corpus cavernosum. However, endothelially generated nitric oxide seems essential for maintaining erection. Endothelial dysfunction can contribute to ED in several patient subgroups. In addition, in conditions associated with reduced function of nerves and endothelium, such as aging, hypertension, smoking, hypercholesterolemia and diabetes, circulatory and structural changes in the penile tissues can result in arterial insufficiency and defect muscle relaxation.. Different types of ED often have overlapping pathophysiologies but may also have common pathways contributing to ED. Such pathways may be potential treatment targets.

Topics: Amides; Animals; Diabetes Mellitus; Endothelin-1; Erectile Dysfunction; Humans; Hypothalamus; Male; Muscle Contraction; Muscle Relaxants, Central; Muscle, Smooth; Nitric Oxide; Norepinephrine; Penile Erection; Phosphorylation; Pyridines; Receptors, Endothelin; rho GTP-Binding Proteins

Diabetes mellitus and impaired glucose tolerance are linked to increased cardiovascular morbidity and mortality. Vascular disease is directly associated with plasma glucose levels, and reduction of these levels forestalls to a certain extent the vascular complications of diabetes, such as myocardial infarction, nephropathies, and retinopathies. In addition to hyperglycemia, there are other risk factors that play a prominent role, such as hypertension, hyperlipidemia, and genetic factors. Endothelial dysfunction is one of the major factors in the development of cardiovascular disease. The vascular endothelium regulates the blood flow by tightly controlling the coagulation system, cell-cell interaction, and vascular tone. These functions are disturbed in diabetic patients. In diabetics, endothelin-1 levels are increased, leading to vasoconstriction. Endothelin levels are directly related to plasma glucose levels. In addition, the endothelial cell-NO axis is disturbed. NO release and function are impaired. This seems to be dependent upon hyperglycemia and genetic factors. Impaired NO function also results in vasoconstriction. Furthermore, enhanced vascular permeability is seen in diabetics. This appears to be related to impaired endothelial cell relaxation and reactive oxygen species as well as advanced glycosylated end products (AGEs). The complex changes seen in diabetes and even prediabetes are therefore related to numerous derailments related to endothelial dysfunction, and no single therapeutic approach is likely to solve the problem of vascular complications.

Topics: Diabetes Mellitus; Endothelin-1; Endothelium, Vascular; Glucose Intolerance; Humans; Vascular Diseases

Erectile dysfunction (ED) is a common problem, particularly in older men. The production of penile erection involves an interplay between autonomic nerves and locally released vasoactive mediators. Endothelin-1 (ET-1) is a peptide released from endothelium in the corpus cavernosum, which causes smooth muscle contraction. Recent studies have investigated the physiological significance of ET-1 in the control of erectile function and it may play a role in detumescence. There is also much evidence to link ET-1 to risk factors for ED. ET-1 antagonists may prove beneficial in the treatment of ED and also in prevention of long term deterioration of erectile function. These antagonists may also find a role when used in combination with agents, which are established for the treatment of ED.

Topics: Animals; Antihypertensive Agents; Bosentan; Diabetes Complications; Diabetes Mellitus; Endothelin-1; Erectile Dysfunction; Humans; Hypercholesterolemia; Hypertension; Male; Myocardial Ischemia; Neural Pathways; Nitric Oxide; Penile Erection; Risk Factors; Smoking; Sulfonamides

There is convincing evidence that the prevalence of erectile dysfunction is increased among men with ischaemic heart disease. This association may be attributed to the fact that both erectile dysfunction and ischaemic heart disease share similar risk factors (e.g. hypertension, dyslipidaemia, diabetes and smoking). Nitric oxide (NO) activity is adversely affected, in penile and vascular tissue, by these risk factors. It is therefore not surprising that a defect in NO activity is thought to play a role in the pathogenesis of both erectile dysfunction and ischaemic heart disease. We consider this evidence and propose that defective NO activity provides a unifying explanation for the association between these two conditions. Further research in this area may improve our understanding of the pathogenesis of cardiovascular diseases as a whole.

Topics: Cardiovascular Diseases; Diabetes Mellitus; Endothelin-1; Humans; Hypercholesterolemia; Male; Muscle, Smooth, Vascular; Nitric Oxide; Penile Erection; Penis

Endothelin-1 is mainly synthesized by the vascular endothelial cells and acts on the vascular smooth muscle. Because of its vasoconstrictor and mitogenic effects it plays a role in the development of vascular diseases. In diabetes mellitus atherosclerosis is accelerated. The authors summarize the available data of the role of endothelin-1 in Type 1 and Type 2 diabetes mellitus and the development of diabetic complication.

Topics: Animals; Diabetes Complications; Diabetes Mellitus; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Endothelin-1; Humans; Rats

This study aims to investigate the effect of hyperbaric oxygen combined with alprostadil in the treatment of elderly diabetic nephropathy (DN) and its effect on serum miR-126 and miR-342 levels. The total effective rate of the study group was 91.53% after treatment, which was higher than that (74.58%) of the control group (p<0.05); the levels of UAER, Scr, BUN and HbA1c, FPG, 2h PG were lowered in the two groups after treatment, and the levels of these indexes were lower in the study group than those in the control group (p<0.05); the levels of vWF, ET-1, CD8+, miR-342 were lowered after treatment for the two groups, and the levels of these indexes were lower in the study group than those in the control group; the levels of NO, CD3+, CD4+ and miR-126 were increased after treatment and the levels were higher in the study group than those in the control group (p<0.05). The application of hyperbaric oxygen combined with alprostadil in the treatment of elderly DN patients can improve renal function, lower blood glucose, improve vascular endothelial function and immune function, adjust serum miR-126 and miR-342 levels, thereby increasing curative effect.

Topics: Aged; Aged, 80 and over; Alprostadil; Blood Glucose; Blood Urea Nitrogen; CD8 Antigens; Creatinine; Diabetes Mellitus; Diabetic Nephropathies; Endothelin-1; Endothelium, Vascular; Female; Glycated Hemoglobin; Humans; Hyperbaric Oxygenation; Male; MicroRNAs; Middle Aged; Treatment Outcome; Vasodilator Agents; von Willebrand Factor

Endothelial microparticles (EMPs) are vehicles released from activated or apoptotic endothelium. The aim of this study was to establish a new cytometric bead assay for EMPs and investigate the prognostic value of EMPs in chest pain patients.. We invented and verified the cytometric bead assay to quantify EMP level in vitro. A total of 80 healthy volunteers and 350 chest pain patients were recruited and the EMPs measured. The major adverse cardiovascular events (MACE) of documented coronary artery disease patients were recorded in the follow-up period. The level of EMPs statistically correlated with those of endothelin-1 (ET-1) and intercellular adhesion molecule-1 (ICAM-1) in vitro. The EMP level in healthy subjects was <300.10. The patients had a remarkably higher EMP level than healthy subjects. Diabetes mellitus, EMP, and ET-1 levels were significantly associated with future cardiovascular events in chest pain patients. There was a significantly higher event incidence in the top tertile EMP level than in the lower tertile in the acute coronary syndrome (ACS) patient group.. A novel EMP quantification assay has been successfully established. The EMPs in vitro and in patients were significantly correlated with ET-1 and ICAM-1 level. The patients with a higher EMP level had a higher risk of MACE. EMP level is a predictor for MACE in ACS patients.

Topics: Aged; Cell-Derived Microparticles; Chest Pain; Coronary Artery Disease; Diabetes Mellitus; Endothelial Cells; Endothelin-1; Female; Flow Cytometry; Follow-Up Studies; Humans; Intercellular Adhesion Molecule-1; Male; Middle Aged; Prognosis

To explore the effects of Tongxinluo Capsule (TXLC) on platelet activating factor, vascular inflammation factor and vascular endothelial function in patients with essential hypertension (EH) complicated with diabetes mellitus (DM).. One hundred patients of EH with DM were equally assigned to the TXLC group (treated by TXLC) and the control group (treated with the conventional therapy). Their fasting blood drawn from the cubital vein on the next morning of hospitalization was taken for determining serum level of high sensitivity C-reactive protein (hs-CRP) by emulsion immunoenhancement turbidimetry; plasmal fibrinogen C (FIB-C) by diffusive turbidimetry; platelet activating indices, CD62p and glucose protein (GP) II b/III a receptor complex by flow cytometry; endothelin-1 (ET-1) by radioimmunoassay and nitrogen oxide (NO) content by enzyme method. The outcomes were compared with those of 50 healthy persons. After patients were treated for 8 weeks, all the above-mentioned indices were reexamined and compared between groups. Results Blood levels of hs-CRP, FIB-C, CD62p, GP II b/IIIa and ET-1 in patients were significantly higher than those in healthy persons (all P < 0.01). All the indices as well as the blood pressure (both systolic and diastolic) reduced in patients of both groups significantly (P < 0.05 or P < 0.01), but the reducing was more significant in the TXLC group than in the control group. Besides, level of NO significantly increased in the TXLC group (P < 0.05).. TXLC can inhibit the platelet activation and vascular inflammation response, also improve the vascular endothelial function in patients with EH complicated with DM. It may play a certain role in preventing and treatment of the occurrence of thrombotic complications in them.

Topics: Aged; Blood Pressure; C-Reactive Protein; Diabetes Mellitus; Drugs, Chinese Herbal; Endothelin-1; Female; Humans; Hypertension; Inflammation; Male; Middle Aged; Platelet Activation

Diabetes is associated with increased risk for complications following coronary bypass grafting (CABG) surgery. Augmented superoxide (*O2*) production plays an important role in diabetic complications by causing vascular dysfunction. The potent vasoconstrictor endothelin-1 (ET-1) is also elevated in diabetes and following CABG; however, the effect of ET-1 on *O2* generation and/or vascular dysfunction in bypass conduits remain unknown. Accordingly, this study investigated basal and ET-1-stimulated *O2* production in bypass conduits and determined the effect of *O2* on conduit reactivity. Saphenous vein specimens were obtained from nondiabetic (n = 24) and diabetic (n = 24) patients undergoing CABG. Dihydroethidium staining and NAD(P)H oxidase activity assays (5380 +/- 940 versus 16,362 +/- 2550 relative light units/microg) demonstrated increased basal *O2* levels in the diabetes group (p < 0.05). Plasma ET-1 levels were associated with elevated basal *O2* levels, and treatment of conduits with exogenous ET-1 further increased *O2* production and augmented vasoconstriction. Furthermore, vascular relaxation was impaired in the diabetic group (75 versus 40%), which was restored by *O2* scavenger superoxide dismutase. These findings suggest that ET-1 causes bypass conduits dysfunction via stimulation of *O2* production in diabetes. Novel therapies that attenuate *O2* generation in bypass conduits may improve acute and late outcome of CABG in diabetic patients.

Topics: Blotting, Western; Coronary Artery Bypass; Coronary Vessels; Diabetes Mellitus; Dose-Response Relationship, Drug; Endothelin-1; Ethidium; Female; Fluorescent Dyes; Humans; Male; Microscopy, Confocal; Middle Aged; Muscle Contraction; Muscle Relaxation; Muscle, Smooth, Vascular; NADPH Oxidases; Reactive Oxygen Species

Endothelin-1 (ET-1) is a potent vasoconstrictor which seems to be involved in the pathogenesis of diabetic retinopathy (DR). However, studies on intraocular ET-1 in DR have been limited. Thus, we investigated aqueous ET-1 levels in patients with DR.. A total 85 subjects were included in this prospective study. Those were classified into three groups: advanced DR group included those with severe nonproliferative DR or proliferative DR, whereas early DR group included those with mild nonproliferative DR or moderative nonproliferative DR. Those who underwent cataract surgery and had no concomitant ocular disease were included in the control group. Aqueous humor levels of ET-1 were obtained before intravitreal bevacizumab injection (IVB) and after 1 month for the DR patients, and at the time of cataract surgery for the control group.. Advanced DR group included 40 eyes (47.1%), whereas early DR group did 19 eyes (22.4%), and control group (26 eyes, 30.5%). Mean aqueous ET-1 level was 10.1±4.1 pg/mL (6.0-21.0 pg/mL) in advanced DR group, 1.9±0.7 pg/mL (0.6-2.8 pg/mL) in early DR group, and 2.1±1.0 pg/mL (0.7-3.9 pg/mL) in control group (P < 0.001). Advanced DR group was further subdivided into severe nonproliferative DR (15 eyes, 12.8%) and proliferative DR (25 eyes, 34.3%). Mean aqueous ET-1 level was 10.1±4.3 pg/mL (6.0-20.1 pg/mL) in patients with severe nonproliferative DR, and 10.0±4.0 pg/mL (6.0-21.0 pg/mL) in those with proliferative DR (P = 0.928) at baseline. Mean ET-1 level at 1 month after intravitreal injection was 2.5±1.0 pg/mL (0.3-4.8 pg/mL) in patients with severe proliferative DR and 2.9±1.7 pg/mL (1.0-7.0 pg/mL) in those with proliferative DR (P = 0.443). Mean aqueous ET-1 level was significantly reduced in both groups (P < 0.001, respectively).. The mean aqueous ET-1 level was significantly higher in the eyes with advanced DR than those with early DR and the control group. The mean aqueous ET-1 level was significantly reduced after intravitreal injections in the advanced DR group. Based on our results, future studies on the exact role of ET-1 in the pathogenesis of DR and future implication for intervention would be helpful for managing DR.

Topics: Aqueous Humor; Bevacizumab; Cataract; Diabetes Mellitus; Diabetic Retinopathy; Endothelin-1; Humans; Prospective Studies

The present study aimed to examine the association between big endothelin-1 (big ET-1) and long-term all-cause death in patients with coronary artery disease (CAD) and different glucose metabolism status.. We consecutively enrolled 8550 patients from January 2013 to December 2013. Patients were categorized according to both status of glucose metabolism status [Diabetes Mellitus (DM), Pre-Diabetes (Pre-DM), Normoglycemia (NG)] and big ET-1 levels. Primary endpoint was all-cause death. During a median of 5.1-year follow-up periods, 301 all-cause deaths occurred. Elevated big ET-1 was significantly associated with long-term all-cause death (adjusted HR: 2.230, 95%CI 1.629-3.051; p < 0.001). Similarly, patients with DM, but not Pre-DM, had increased risk of all-cause death compared with NG group (p < 0.05). When patients were categorized by both status of glucose metabolism and big ET-1 levels, high big ET-1 were associated with significantly higher risk of all-cause death in Pre-DM (adjusted HR: 2.442, 95% CI 1.039-5.740; p = 0.041) and DM (adjusted HR: 3.162, 95% CI 1.376-7.269; p = 0.007). The Kaplan-Meier curve indicated that DM patients with the highest big ET-1 levels were associated with the greatest risk of all-cause death (p < 0.05).. The present data indicate that baseline big ET-1 levels were independently associated with the long-term all-cause death in DM and Pre-DM patients with CAD undergoing PCI, suggesting that big ET-1 may be a valuable marker in patients with impaired glucose metabolism.

Topics: Blood Glucose; Coronary Artery Disease; Diabetes Mellitus; Endothelin-1; Humans; Percutaneous Coronary Intervention; Prediabetic State; Risk Factors; Time Factors; Treatment Outcome

Critical limb ischemia (CLI) is a severe manifestation of peripheral artery disease characterized by ischemic pain, which is frequently associated with diabetes and non-healing lesions to inferior limbs. The clinical management of diabetic patients with CLI typically includes percutaneous transluminal angioplasty (PTA) to restore limb circulation and surgical treatment of diabetic foot ulcers (DFU). However, even after successful treatment, CLI patients are prone to post-procedure complications, which may lead to unplanned revascularization or foot surgery. Unfortunately, the factors predicting adverse events in treated CLI patients are only partially known. This study aimed to identify potential biomarkers that predict the disease course in diabetic patients with CLI. For this purpose, we measured the circulating levels of a panel of 23 molecules related to inflammation, endothelial dysfunction, platelet activation, and thrombophilia in 92 patients with CLI and DFU requiring PTA and foot surgery. We investigated whether these putative biomarkers were associated with the following clinical endpoints: (1) healing of the treated DFUs; (2) need for new revascularization of the limb; (3) appearance of new lesions or relapses after successful healing. We found that sICAM-1 and endothelin-1 are inversely associated with DFU healing and that PAI-1 and endothelin-1 are associated with the need for new revascularization. Moreover, we found that the levels of thrombomodulin and sCD40L are associated with new lesions or recurrence, and we show that the levels of these biomarkers could be used in a decision tree to assign patients to clusters with different risks of developing new lesions or recurrences.

Topics: Amputation, Surgical; Biomarkers; Chronic Limb-Threatening Ischemia; Diabetes Mellitus; Diabetic Foot; Endothelin-1; Humans; Inflammation; Ischemia; Plasminogen Activator Inhibitor 1; Retrospective Studies; Thrombomodulin; Treatment Outcome

Topics: Albuminuria; Atrasentan; Diabetes Mellitus; Diabetic Nephropathies; Endothelin A Receptor Antagonists; Endothelin Receptor Antagonists; Endothelin-1; Humans; Pyrrolidines

Rhodiola crenulata root extract (RCE), a traditional Chinese medicine, has been shown to regulate glucose and lipid metabolism via the AMPK pathway in high glucose (HG) conditions. However, the effect of RCE on HG-induced endothelial dysfunction remains unclear. The present study was designed to examine the effects and mechanisms of RCE against hyperglycemic insult in endothelial cells. Human umbilical vein endothelial cells (HUVECs) were pretreated with or without RCE and then exposed to 33[Formula: see text]mM HG medium. The cell viability, nitrite production, oxidative stress markers, and vasoactive factors, as well as the mechanisms underlying RCE action, were then investigated. We found that RCE significantly improved cell death, nitric oxide (NO) defects, and oxidative stress in HG conditions. In addition, RCE significantly decreased the HG-induced vasoactive markers, including endothelin-1 (ET-1), fibronectin, and vascular endothelial growth factor (VEGF). However, the RCE-restored AMPK-Akt-eNOS-NO axis and cell viability were abolished by the presence of an AMPK inhibitor. These findings suggested that the protective effects of RCE were associated with the AMPK-Akt-eNOS-NO signaling pathway. In conclusion, we showed that RCE protected endothelial cells from hyperglycemic insult and demonstrated its potential for use as a treatment for endothelial dysfunction in diabetes mellitus.

Topics: Cell Survival; Diabetes Mellitus; Endothelin-1; Endothelium, Vascular; Fibronectins; Glucose; Human Umbilical Vein Endothelial Cells; Humans; Lipid Metabolism; MAP Kinase Signaling System; Nitric Oxide; Oxidative Stress; Phytotherapy; Plant Extracts; Rhodiola; Vascular Endothelial Growth Factor A

Increased endothelin (ET)-1 expression causes endothelial dysfunction and oxidative stress. Plasma ET-1 is increased in patients with diabetes mellitus. Since endothelial dysfunction often precedes vascular complications in diabetes, we hypothesized that overexpression of ET-1 in the endothelium would exaggerate diabetes-induced endothelial dysfunction.. Diabetes was induced by streptozotocin treatment (55mg/kg/day, i.p.) for 5 days in 6-week-old male wild type (WT) mice and in mice overexpressing human ET-1 restricted to the endothelium (eET-1). Mice were studied 14 weeks later. Small mesenteric artery (MA) endothelial function and vascular remodeling by pressurized myography, reactive oxygen species (ROS) production by dihydroethidium staining and mRNA expression by reverse transcription/quantitative PCR were determined.. Endothelium-dependent vasodilatory responses to acetylcholine of MA were reduced 24% by diabetes in WT ( P < 0.05), and further decreased by 12% in eET-1 ( P < 0.05). Diabetes decreased MA media/lumen in WT and eET-1 ( P < 0.05), whereas ET-1 overexpression increased MA media/lumen similarly in diabetic and nondiabetic WT mice ( P < 0.05). Vascular ROS production was increased 2-fold by diabetes in WT ( P < 0.05) and further augmented 1.7-fold in eET-1 ( P < 0.05). Diabetes reduced endothelial nitric oxide synthase (eNOS, Nos3 ) expression in eET-1 by 31% ( P < 0.05) but not in WT. Induction of diabetes caused a 52% ( P < 0.05) increase in superoxide dismutase 1 ( Sod1 ) and a 32% ( P < 0.05) increase in Sod2 expression in WT but not in eET-1.. Increased expression of ET-1 exaggerates diabetes-induced endothelial dysfunction. This may be caused by decrease in eNOS expression, increase in vascular oxidative stress, and decrease in antioxidant capacity.

Topics: Animals; Diabetes Mellitus; Endothelin-1; Endothelium, Vascular; Humans; Male; Mice; Mice, Inbred C57BL; Nitric Oxide; Nitric Oxide Synthase Type III; Oxidative Stress; Reactive Oxygen Species

Contrast media-induced nephropathy (CIN) is associated with increased morbidity and mortality. The renal endothelin system has been associated with disease progression of various acute and chronic renal diseases. However, robust data coming from adequately powered prospective clinical studies analyzing the short and long-term impacts of the renal ET system in patients with CIN are missing so far. We thus performed a prospective study addressing this topic.. We included 327 patients with diabetes or renal impairment undergoing coronary angiography. Blood and spot urine were collected before and 24 h after contrast media (CM) application. Patients were followed for 90 days for major clinical events like need for dialysis, unplanned rehospitalization or death.. The concentration of ET-1 and the urinary ET-1/creatinine ratio decreased in spot urine after CM application (ET-1 concentration: 0.91±1.23 pg/ml versus 0.63±1.03 pg/ml, p<0.001; ET-1/creatinine ratio: 0.14±0.23 versus 0.09±0.19, p<0.001). The urinary ET-1 concentrations in patients with CIN decreased significantly more than in patients without CIN (-0.26±1.42 pg/ml vs. -0.79±1.69 pg/ml, p=0.041), whereas the decrease of the urinary ET-1/creatinine ratio was not significantly different (non-CIN patients: -0.05±0.30; CIN patients: -0.11±0.21, p=0.223). Urinary ET-1 concentrations as well as the urinary ET-1/creatinine ratio were not associated with clinical events (need for dialysis, rehospitalization or death) during the 90 day follow-up after contrast media exposure. However, the urinary ET-1 concentration and the urinary ET-1/creatinine ratio after CM application were higher in those patients who had a decrease of GFR of at least 25% after 90 days of follow-up.. In general the ET-1 system in the kidney seems to be down-regulated after contrast media application in patients with moderate CIN risk. Major long-term complications of CIN (need for dialysis, rehospitalization or death) are not associated with the renal ET system.

Topics: Aged; Cohort Studies; Contrast Media; Creatinine; Diabetes Mellitus; Endothelin-1; Female; Humans; Kidney Function Tests; Male; Radiopharmaceuticals

Chronic hyperglycemia exerts a deleterious effect on endothelium, contributing to endothelial dysfunction and microvascular complications in poorly controlled diabetes. To understand the underlying mechanism, we studied the effect of endothelin-1 (ET-1) on endothelial production of Forkhead box O1 (FOXO1), a forkhead transcription factor that plays an important role in cell survival. ET-1 is a 21-amino acid peptide that is secreted primarily from endothelium. Using adenovirus-mediated gene transfer approach, we delivered FOXO1 cDNA into cultured human aorta endothelial cells. FOXO1 was shown to stimulate B cell leukemia/lymphoma 2-associated death promoter (BAD) production and promote cellular apoptosis. This effect was counteracted by ET-1. In response to ET-1, FOXO1 was phosphorylated and translocated from the nucleus to cytoplasm, resulting in inhibition of BAD production and mitigation of FOXO1-mediated apoptosis. Hyperglycemia stimulated FOXO1 O-glycosylation and promoted its nuclear localization in human aorta endothelial cells. This effect accounted for unbridled FOXO1 activity in the nucleus, contributing to augmented BAD production and endothelial apoptosis under hyperglycemic conditions. FOXO1 expression became deregulated in the aorta of both streptozotocin-induced diabetic mice and diabetic db/db mice. This hyperglycemia-elicited FOXO1 deregulation and its ensuing effect on endothelial cell survival was corrected by ET-1. Likewise, FoxO1 deregulation in the aorta of diabetic mice was reversible after the reduction of hyperglycemia by insulin therapy. These data reveal a mechanism by which FOXO1 mediated the autocrine effect of ET-1 on endothelial cell survival. FOXO1 deregulation, resulting from an impaired ability of ET-1 to control FOXO1 activity in endothelium, may contribute to hyperglycemia-induced endothelial lesion in diabetes.

Topics: Animals; Aorta; Apoptosis; bcl-Associated Death Protein; Cell Line; Cell Survival; Diabetes Mellitus; Endothelial Cells; Endothelin-1; Female; Forkhead Box Protein O1; Forkhead Transcription Factors; Gene Transfer Techniques; Humans; Hyperglycemia; Insulin; Mice; Mice, Inbred ICR; Mice, Transgenic; Phosphorylation; Random Allocation

We compared the contractile responses to endothelin-1 (ET-1) with and without the inhibition of ET-A receptors and protein kinase C-alpha (PKC-α) in the human peripheral microvasculature of diabetic and case-matched, nondiabetic patients.. Chest wall skeletal muscle was harvested from patients with and without diabetics undergoing cardiac surgery. Peripheral arterioles (90-180 μm in diameter) were dissected from the harvested tissue. Microvascular constriction was assessed by videomicroscopy in response to ET-1 with and without an endothelin-A (ET-A) receptor antagonist, an endothelin B (ET-B) antagonist, or a PKC-α inhibitor.. ET-1 induced a dose-dependent contractile response of skeletal muscle arterioles from diabetic and nondiabetic patients. The contractile response of diabetic arterioles from both prebypass and postbypass to ET-1 (10(-9) mol/L) was decreased compared with those of nondiabetic patients (P < .05). The contractile responses of microvessels of both diabetics and nondiabetics to ET-1 were inhibited in the presence of either ET-A receptor antagonist BQ123 (10(-7) mol/L) or the PKC-α inhibitor safingol (2 × 10(-5) mol/L, P < .05, respectively). In contrast, the ET-1-induced vasoconstriction was not affected by the administration of the ET-B receptor antagonist BQ788 (10(-7) mol/L). There were no differences in skeletal muscle levels of the ET-A and ET-B receptors between diabetic and nondiabetic groups.. Diabetic patients demonstrated a decreased contractile response to ET-1 in human peripheral microvasculature. The contractile response of diabetic vessels to ET-1 occurs via activation of ET-A receptors and PKC-α. These results provide novel mechanisms of ET-1-induced contraction in vasomotor dysfunction in patients with diabetes.

Topics: Aged; Arterioles; Diabetes Mellitus; Dose-Response Relationship, Drug; Endothelin-1; Female; Glycation End Products, Advanced; Humans; Male; Middle Aged; Protein Kinase C-alpha; Receptor, Endothelin A; Receptor, Endothelin B; Vasoconstriction

Increased expression of endothelin converting enzyme-1 (ECE-1) is associated with diabetic nephropathy. The molecular mechanisms underlying this association, as yet unknown, possibly involve protein kinase C (PKC) pathways. In the present study, we examined the effects of high glucose and PKC activation on ECE-1 expression in primary human umbilical vein endothelial cells (HUVECs) and in HUVEC line (EA.hy926). Increasing glucose concentration, but not mannitol, from 5.5-22.2 mmol/liter for 3 d, enhanced prepro endothelin-1 (ET-1) mRNA expression, ET-1 levels, ECE-1 protein, and mRNA expressions by 7, 4, 20, and 2.6-fold, respectively. High glucose increased ECE-1 protein expression dose and time dependently. By Western blot analysis, PKC-beta1, -beta2, and -delta isoform levels were significantly increased relative to other isoforms when glucose level was increased. Treatment with Rottlerin, a PKC-delta isoform inhibitor, reduced significantly the glucose-induced ET-1 secretion, and ECE-1 protein expression, but (S)-13-[(dimethylamino)methyl]-10,11,14,15-tetrahydro-4,9:16,21-dimetheno 1H,1(3)H-dibenzo[e,k]pyrrolo[3,4-h] (1, 4, 3) oxadiaza-cyclohexadecene-1,3(2H)-dione or Gö6976, specific PKC-beta and -alpha inhibitors, respectively, did not. Overexpression of PKC-delta but not PKC-alpha or -beta1 isoforms by adenovirus vector containing the respective cDNA in HUVECs incubated with 5.5 mmol/liter glucose, increased in parallel PKC proteins, and glucose-induced endothein-1 and ECE-1 protein expression by 4- to 6-fold. These results show that enhanced ECE-1 expression induced by hyperglycemia is partly due to activation of the PKC-delta isoform. Thus, inhibition of this PKC isoform may prevent diabetes-related increase in ET-1.

Topics: Aspartic Acid Endopeptidases; Cells, Cultured; Diabetes Mellitus; Dose-Response Relationship, Drug; Endothelin-1; Endothelin-Converting Enzymes; Endothelins; Gene Expression Regulation, Enzymologic; Glucose; Humans; Hyperglycemia; Isoenzymes; Metalloendopeptidases; Protein Kinase C; Protein Kinase Inhibitors; Signal Transduction; Substrate Specificity

Topics: Antirheumatic Agents; Arthritis, Rheumatoid; Coronary Circulation; Diabetes Mellitus; Endothelin-1; Humans; Hyperalgesia; Hypertension, Pulmonary; Interleukin 1 Receptor Antagonist Protein; Interleukin-1; Myocardial Infarction; Pneumonia; Receptors, Tumor Necrosis Factor; Syndrome

To explore the protective mechanism of officeihale on the vascular pathological process in diabetes mellitus (DM) rats.. After the DM rat model was established, 24 DM rats were randomly divided into model group (12 DM rats) and Rheum officeinale group (12 DM rats). Rheum officeinale was orally given in 10 g kg(-1) per day, and the other two groups were given equal pure water. 8 weeks later, blood samples were collected to determine the level of nitric oxide (NO) and endothelin-1 (ET-1). Thoracic aortic rings was prepared to observe the inhibiting effect of Ach with different concentration on contraction caused by NE. Another part of aorta was made to observe the expression of ICAM-1 and VCAM-1 by method of SP immunohistochemistry staining,. Rheum officeinale group obviously decreased the level of ET-1 and increased the NO compared with model group (P <0.05). The expression of ICAM-1 and VCAM-1 could be obviously inhibited in Rheum officeinale group compared with model group. (P <0.05).. Rheum officeinale could decrease the level of ET-1 with increased the NO in diabetes rats, and inhibit the expression of ICAM-1 and VCAM-1, which may be mechanisms of protecting the endothelium of vessel in diabetes rats.

Topics: Animals; Aorta; Blood Glucose; Blood Vessels; Diabetes Mellitus; Drugs, Chinese Herbal; Endothelin-1; Endothelium, Vascular; Gene Expression Regulation; Intercellular Adhesion Molecule-1; Male; Nitric Oxide; Protective Agents; Rats; Rheum

The study objective is to prove an association among plasma concentration of big endothelin and endothelin-1, other clinical parameters and two frequent polymorphisms - G8002A and -3A/-4A - in the endothelin-1 (EDN-1) coding gene (6p21-23), and among plasma concentration of TNF alpha and gene polymorphisms TNF alpha -308 A/G, -238 A/G, TNF beta Ncol and 3'TACE (tumour necrosis factor alpha converting enzyme) in patients with chronic heart failure (CHF). The second objective is to find an association between polymorphisms G8002A and -3A/4A EDN-1 with diabetes mellitus (DM), peripheral artery disease (PAD) and myocardial infarction (MI) in patients with chronic heart failure (CHF). The study population included 266 patients with symptomatic CHF and proven dysfunction of the left ventricle (LV). Genotyping and plasma concentrations of humoral substances were examined in 224 patients with ejection fraction (EF) below 40%. No associations between plasma concentrations of endothelin-1 and big endothelin and polymorphisms G8002A (p=0.87, p=0.81) and -3A/-4A (p=0.871, p=0.749) in the gene coding endothelin-1 were found. No associations were observed between plasma concentration of TNF alpha and genotypes in four polymorphisms in TNF alpha, beta and TACE genes. A significant correlation was seen between plasma concentration of big endothelin and pulmonary congestion. Patients with ischemic heart disease (IHD) and previous MI showed a difference in the distribution of genotype G8002A for endothelin-1: allele G 0.718 and A 0.282 vs those without MI: allele G 0.882 and A 0.118, (p<0.05). Patients with IHD and DM had allele G in 0.67 and A 0.33, while those without DM had allele G in 0.790 and A in 0.209 (p<0.03). Patients with IHD and concomitant PAD had allele G in 0.718 and A in 0.282 vs those without PAD allele G in 0.882 and A in 0.118 (p<0.0004). Patients with dilative cardiomyopathy (DCMP) showed no differences in genotype G8002A and presence of DM or PAD. It might be speculated that in the case of endothelin-1 and TNF alpha in CHF the genetic determination is not important, and plasma concentrations are influenced more by the disease severity. Ischemics with previous MI, concomitant DM or PAD showed more frequently allele A and less often allele G than those without these diseases. A genotype with allele A is associated with higher risk of concomitant diseases.

Topics: Biomarkers; Chronic Disease; Cytokines; Diabetes Mellitus; Endothelin-1; Female; Genetic Predisposition to Disease; Heart Failure; Humans; Male; Middle Aged; Myocardial Infarction; Peripheral Vascular Diseases; Polymorphism, Genetic; Risk Assessment

Objective of the work is to determine the relation of G8002 polymorhism in endothelin 1 gene to the incidence of diabetes mellitus (DM), ischemic disease of lower limbs (ID LL) and myocardial infarction (MI) at the patients with heart failure. METHODICS: There were observed 224 patients, 176 males, 48 females, average age 55 +/- 12 years, NYHA II/III/IV 82/131/11, average EF LK 25 +/- 7 %, diagnosis ischemic heart disease (IHD) 133, dilatation cardiomyopathy (DCMP) 91.. Patients with IHD had higher incidence of hypertension (p < 0.0007), diabetes mellitus (p < 0.00007) and hyperlipoproteinemy (p < 0.0006) than patients with DCMP. Patients with IHD who experienced MI had a difference in the distribution of G8002A genotypes for endothelin 1 gene: G 0.718 and A 0.282 alleles vs ischemic patients without MI G 0.882 and A 0.118 (p < 0.05) alleles. Ischemic patients with DM had G allele in 0.67 and A 0.33 unlike ischemic patients without DM G allele 0.791 and A 0.209 (p < 0.03). Ischemic patients with synchronous ID LL had G allele in 0.718 and A 0.282 vs ischemic patients without ID LL G allele 0.882 and A 0.118 (p < 0.0004). At the patients with DCMP there was not found a difference in G8002A genotype and the presence of DM or ID LL.. At the patients with heart failure on the basis of ischemic heart disease there was found a difference in endothelin G8002A genotype distribution depending on other accessory diseases. There was more frequently present an A allele and less present G allele in the ischemic patients with DM, who had experienced MI or ID LL than in the ischemic patients without these diseases. Genotype with A allele is connected with higher risk of all accessory diseases.

Topics: Alleles; Diabetes Mellitus; Endothelin-1; Female; Genetic Predisposition to Disease; Genotype; Heart Failure; Humans; Ischemia; Leg; Male; Middle Aged; Myocardial Infarction; Myocardial Ischemia; Polymorphism, Genetic

The effects of calcium channel blockers (CCBs) on complications associated with diabetes mellitus (DM) have been well studied in clinical and basic science investigations. Cardiovascular complications are a common feature of type 2 DM, and insulin resistance is an early clinical manifestation of type 2 DM. CCBs are widely used to treat cardiovascular diseases in patients with DM. In this study, we used a spontaneous type 2 diabetic rat model, Otsuka Long-Evans Tokushima Fatty (OLETF) rats, at a highly insulin-resistant stage with modest hyperglycemia. We examined cardiac expression of transforming growth factor-beta(1) (TGFbeta(1)) and endothelin-1 (ET-1) in male OLETF rats. At 8 weeks of age, OLETF rats were treated for 12 weeks with the long-acting CCB benidipine (1 mg/kg/day or 3 mg/kg/day, po, n = 12), with hydralazine hydrochloride (3 mg/kg/day, po, n = 12), or with vehicle (OLETF, n = 12), and male age-matched genetic control Long-Evans Tokushima Otsuka (LETO, n = 12) rats were used. Blood pressure was significantly higher in OLETF rats than in LETO rats, and benidipine treatment at both dosages in OLETF rats for 12 weeks did not significantly reduce blood pressure, whereas hydralazine treatment significantly lowered blood pressure in OLETF rats. Hydralazine and both dosages of benidipine significantly reduced upregulated cardiac ET-1 levels in OLETF rats. Plasma and cardiac TGFbeta1 levels were remarkably higher in OLETF rats compared with LETO rats and were normalized by treatment with benidipine (3 mg/kg/day). Our results suggest that CCBs are effective in normalizing upregulated cardiac TGFbeta1 and ET-1 levels at the insulin-resistant stage in OLETF rats, which may improve cardiac morphology and function in this rat model without altering blood pressure and plasma glucose levels. In contrast, hydralazine treatment also normalizes cardiac ET-1 levels while significantly reducing blood pressure.

Topics: Animals; Blood Glucose; Blood Pressure; Calcium Channel Blockers; Diabetes Mellitus; Dihydropyridines; Dose-Response Relationship, Drug; Endothelin-1; Endothelium, Vascular; Hydrazines; Insulin; Male; Random Allocation; Rats; Rats, Inbred OLETF; Rats, Long-Evans; Transforming Growth Factor beta

Fibronectin (FN), a key extracellular matrix protein, is upregulated in target organs of diabetic angiopathy and in cultured cells exposed to high levels of glucose. FN has also been reported to undergo alternative splicing to produce the extra domain-B (ED-B) containing isoform, which is exclusively expressed during embryogenesis, tissue repair, and tumoral angiogenesis. The present study was aimed at elucidating the role and mechanism of endothelins (ETs) in FN and ED-B FN expression in diabetes. We investigated vitreous samples for ED-B FN expression from patients undergoing vitrectomy for proliferative diabetic retinopathy. Our results show increased FN and ED-B FN expression in the vitreous of diabetic patients in association with augmented ET-1. Using an antibody specific to the ED-B segment of FN, we show an increase in serum ED-B FN levels in patients with diabetic retinopathy and nephropathy. We further examined retinal tissues, as well as renal and cardiac tissues, from streptozotocin-induced diabetic rats. Diabetes increased FN and ED-B FN in all three organs, which was prevented by ET antagonist bosentan. To provide insight into the mechanism of glucose-induced and ET-mediated ED-B FN upregulation, we assayed endothelial cells (ECs). Inhibition of mitogen-activated protein kinase with pharmacological inhibitors and protein kinase B with dominant negative transfections prevented glucose- and ET-1-mediated FN and ED-B FN expression. Furthermore, treatment of cells exposed to high levels of glucose with ET antagonist prevented the activation of all signaling pathways studied and normalized glucose-induced ED-B FN expression. We then determined the functional significance of ED-B in ECs and show that ED-B FN is involved in vascular endothelial growth factor expression and cellular proliferation. These studies show that glucose-induced and ET-mediated FN and ED-B FN expressions involve complex interplays between signaling pathways and that ET may represent an ideal target for therapy in chronic diabetic complications.

Topics: Adult; Aged; Animals; Case-Control Studies; Cells, Cultured; Diabetes Mellitus; Diabetes Mellitus, Experimental; Endothelin-1; Endothelium, Vascular; Extracellular Matrix; Female; Fibronectins; Humans; Male; Middle Aged; Models, Biological; Rats; Rats, Sprague-Dawley; RNA, Messenger; Umbilical Veins; Vitreous Body

Low adipocyte IRS-1 protein expression is a biomarker for insulin resistance and early atherosclerosis. However, whether IRS-1 protein expression is related to systemic arterial stiffness, is unknown.. Ten non-diabetic male subjects with low adipocyte IRS-1 protein expression (LIRS) were matched with 10 non-diabetic males with normal IRS-1 protein expression (NIRS). Augmentation index (AIx) and time for reflection of pulse wave (Tr) were studied with pulse wave analysis, both in the fasting state and during a euglycemic hyperinsulinemic clamp. The LIRS-group showed an increased fasting insulin concentration (fP-insulin 71+/-4 pmol/L versus 58+/-5 pmol/L; p=0.02 (mean+/-S.E.)), whereas glucose disposal rate during the clamp (8.7+/-0.8 mg/kg LBM/min versus 10.3+/-1.3 mg/kg LBM/min; n.s.) did not differ significantly. Blood pressure, lipid parameters, adiponectin, endothelin-1 and CRP concentrations were similar. However, in the basal state, AIx was increased (129+/-4% versus 116+/-2%; p<0.02) and Tr was decreased (150+/-3 ms versus 171+/-5 ms; p<0.01), suggesting stiffer vessels in the LIRS-group. The LIRS-group exhibited an attenuated AIx response to hyperinsulinemia compared to the NIRS-group.. The data suggest that non-obese non-diabetic men with a low adipocyte IRS-1 protein expression have an increased systemic arterial stiffness.

Topics: Adipocytes; Adiponectin; Adult; Arteriosclerosis; Biomarkers; Blood Glucose; C-Reactive Protein; Diabetes Mellitus; Endothelin-1; Fasting; Female; Glucose Clamp Technique; Humans; Hyperinsulinism; Insulin Receptor Substrate Proteins; Insulin Resistance; Intercellular Signaling Peptides and Proteins; Male; Middle Aged; Phosphoproteins

Understanding the causes of diabetic vascular complications has become an increasingly important issue because of the rapidly rising prevalence of diabetes. Recently discovered vasoconstrictors and angiogenesis regulators, such as endothelin (ET) and vascular endothelial growth factor (VEGF), have been intensely studied for possible pathogenic roles in diabetic vascular complications. The present study was undertaken to clarify the effect of glycemic control on serum VEGF and plasma ET-1 concentrations in diabetic patients, and to identify other factors that may cause fluctuations of these substances. Plasma VEGF and ET-1 concentrations of 45 hospitalized diabetic patients and 54 control subjects were measured by enzyme immunoassay (EIA) and radioimmunoassay (RIA), respectively. Plasma VEGF was elevated in poorly controlled diabetic patients compared with healthy subjects and plasma VEGF concentrations declined after hospitalized treatment with either insulin or oral hypoglycemic agents in combination with diet. There was a significant correlation between plasma VEGF concentration and both fasting plasma glucose (FPG) and hemoglobin A(1c) (HbA(1c)). Plasma ET-1 in poorly controlled diabetic patients was higher than in healthy controls, but improved glycemic control did not affect plasma ET-1 concentrations. Thus, poor glycemic control causes increased levels of plasma VEGF, which may result in hypertension and vascular complications in diabetes. Short-term treatment resulting in good glycemic control can improve levels of VEGF and may provide beneficial effects on diabetic vascular complications.

Topics: Adult; Aged; Blood Glucose; Body Mass Index; Case-Control Studies; Diabetes Complications; Diabetes Mellitus; Diabetic Neuropathies; Diabetic Retinopathy; Endothelin-1; Fasting; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Male; Middle Aged; Proteinuria; Regression Analysis; Vascular Endothelial Growth Factor A

Mitral annulus calcification (MAC) is a chronic degenerative noninflammatory process. The goal of this study was to determine endothelin-1 (ET-1) and nitric oxide (NOx) levels in patients with MAC and compare them with those in normal subjects. The study group included 39 patients [26 females (66%), age, 63 +/- 8 years] with MAC and 20 [11 females (55%), age, 61 +/- 7 years] healthy subjects. The patients were divided into two subgroups, group A with severe MAC and group B with mild MAC, according to the severity of the MAC. Plasma ET-1 levels were higher and NOx levels were lower in patients than controls [(6.5 +/- 5.6 pg/mL vs 3.7 +/- 2.9 pg/mL for ET-1 and 35.0 +/- 10.6 micromol/L vs 42.3 +/- 9.9 micromol/L for NOx; P < 0.05 for both)]. In the subgroups, ET-1 levels were higher in group A than group B (8.65 +/- 6.84 pg/mL vs 4.74 +/- 3.45 pg/mL, P < 0.05) and the control group (8.65 +/- 6.84 pg/mL vs 3.70 +/- 2.88 pg/mL, P < 0.05). There was no difference between group B and the control group. Plasma NOx levels were significantly decreased in group A compared to controls (32.22 +/- 11.88 micromol/L vs 42.25 +/- 9.99 micromol/L, P < 0.05). However, no significant difference was observed between group B (37.38 +/- 9.06 micromol/L) and the other groups. Diabetes mellitus, coronary artery disease, and dyslipidemia were significantly associated with ET-1 levels. However, this association was not observed for NOx. In conclusion, patients with MAC have increased ET-1 and decreased NOx levels. This seems to be more prominent in patients with severe MAC.

Topics: Aged; Calcinosis; Coronary Disease; Diabetes Mellitus; Echocardiography; Echocardiography, Doppler, Color; Endothelin-1; Female; Heart Valve Diseases; Humans; Male; Middle Aged; Mitral Valve; Nitrates; Nitric Oxide; Nitrites

Endothelial dysfunction reflects an imbalance of vasodilators and vasoconstrictors. Endogenous endothelin activity seems to be increased in human obesity and type 2 diabetes, and cellular studies suggest that this factor may itself reduce bioavailable nitric oxide (NO). We studied 20 lean, 20 obese, and 14 type 2 diabetic individuals under three protocols, measuring leg vascular responses to intra-arterial infusions of NG-monomethyl-l-arginine (l-NMMA; an inhibitor of NO synthase) alone or in combination with BQ123 (an antagonist of type A endothelin receptors) or phentolamine (used as a control vasodilator). NO synthase inhibition alone (study 1) produced an approximately 40% increase in leg vascular resistance (LVR) in all three participant groups, which was not statistically different across groups (increase in LVR: lean, 135 +/- 28; obese, 140 +/- 32; type 2 diabetic, 184 +/- 51 units; NS). By design, BQ123 at the infused rate of 3 micromol/min produced equivalent approximately 35% reductions in LVR across groups. The subsequent addition of l-NMMA produced a greater increase in LVR among obese participants than lean or type 2 diabetic participants (study 2: lean, 182 +/- 48; obese, 311 +/- 66; type 2 diabetic, 186 +/- 40; P = 0.07). Compared with study 1, the effect of l-NMMA was magnified by BQ123 in obese participants but not in lean or type 2 diabetic participants (P = 0.005, study 1 vs. 2; P = 0.03 for group effect). Phentolamine (75 mg/min) produced vasodilation in obese participants comparable to that seen with BQ123 but failed to augment the L-NMMA response. Endothelin antagonism unmasks or augments NO synthesis capacity in obese but not type 2 diabetic participants. This suggests that impaired NO bioavailability as a result of endogenous endothelin may contribute to endothelial dysfunction in obesity, in addition to direct vasoconstrictor effects of endothelin. In contrast, endothelin antagonism alone is insufficient to restore impaired NO bioavailability in diabetes.

Topics: Blood Pressure; Diabetes Mellitus; Endothelin Receptor Antagonists; Endothelin-1; Endothelins; Humans; Muscle, Smooth, Vascular; Nitric Oxide; Obesity; omega-N-Methylarginine; Peptides, Cyclic; Reference Values; Vascular Resistance

The Cohen-Rosenthal diabetic hypertensive rat is a unique animal model in which genetic hypertension and diabetes developed after crossbreeding of a sensitive substrain of Cohen diabetic rats and spontaneously hypertensive rats (SHR) and feeding them a copper-poor sucrose diet. This study examined the acute effects of endothelin-1 on the systemic and renal hemodynamics in Cohen-Rosenthal diabetic hypertensive rats, Cohen diabetic rats and spontaneously hypertensive rats. Intravenous injection of endothelin- 1 (1.0 nmol/kg) into anesthetized SHR resulted in a significant immediate depressor response in mean arterial pressure [from 165 +/- 3 mmHg to 124 +/- 12 mmHg (P < 0.0001)] followed by a minor hypertensive phase (mean arterial pressure increased to 170 +/- 2 mmHg). Simultaneously, the administration of endothelin-1 caused a significant decrease in renal blood flow from 5.8 +/- 0.9 mL/minute to 3.2 +/- 0.5 mL/minute (P = 0.026). These responses were blunted in Cohen-Rosenthal diabetic hypertensive rats and Cohen diabetic rats. Analysis of intrarenal blood flow by laser-Doppler in Cohen-Rosenthal diabetic hypertensive rats revealed that endothelin-1 injection caused a decrease in cortical blood flow (Delta = -12 +/- 2.9%). However, in contrast to its well known renal medullary vasodilatory effect, endothelin-1 produced a significant decline in the medulla blood flow (Delta = -17.5 +/- 3.4%) (P = 0.0125). These findings suggest that Cohen diabetic rats and Cohen-Rosenthal diabetic hypertensive rats have reduced sensitivity to the vascular and renal action of endothelin-1. Furthermore, in the Cohen-Rosenthal diabetic hypertensive rats the expected endothelin- 1-induced medullary vasodilation was abolished and even reversed into prolonged vasoconstrictor response.

Topics: Animals; Blood Pressure; Copper; Diabetes Mellitus; Dietary Sucrose; Disease Models, Animal; Endothelin-1; Hemodynamics; Injections, Intravenous; Kidney; Rats; Rats, Inbred SHR; Renal Circulation; Vascular Resistance; Vasoconstriction; Vasodilation

Plasma endothelin-1 was measured around the clock in 72 subjects. Cosinor methods were used to assess circadian and other recurrent variation and trends, that is, the time structure (chronome) of this peptide. Multifactorial analyses of variance and linear regressions assessed chronome alterations associated with different risk factors: diabetes, obesity, high cholesterol, high blood pressure, vascular disease, smoking, and age. The rhythm-adjusted mean (MESOR) of endothelin-1 is elevated in diabetes and vascular disease. Diabetes is also associated with a larger circadian amplitude. A circadian variation in a subgroup of low-risk subjects is modulated by components with both lower and higher frequency.

Topics: Adult; Aged; Circadian Rhythm; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Endothelin-1; Female; Humans; Hypertension; Male; Middle Aged; Periodicity; Regression Analysis; Risk Factors; Time Factors; Vascular Diseases

We evaluated plasma concentration of endothelin-1 in diabetic and nondiabetic men complaining of erectile dysfunction, and the variation of endothelin-1 in cavernous body blood during intracavernous injection of prostaglandin E1.. We evaluated plasma concentrations of endothelin-1 in venous blood of 20 men with erectile dysfunction, 10 with and 10 without diabetes. Plasma concentration of endothelin-1 was also evaluated in the cavernous body blood of the 20 men with erectile dysfunction, during erection induced by intracavernous injection of 10 micrograms prostaglandin E1. A severe vasculogenic component of erectile dysfunction was excluded in all patients.. Basal plasma concentration of endothelin-1 in the cubital vein was increased in nondiabetic (1.13 +/- 0.4 pg./ml.) and in diabetic (1.80 +/- 0.2 pg./ml.) patients with erectile dysfunction, compared to control men (0.64 +/- 0.1 pg./ml.) (p < 0.0005 and p < 0.0001, respectively), and in diabetic compared with nondiabetic patients (p < 0.002). No difference and close correlation were observed in the concentration of endothelin-1 in the cavernous body blood evaluated 5 minutes and 30 minutes after injection of prostaglandin E1 (r = 0.89, p < 0.0001, y = 0.98 x + -0.066). The concentration of endothelin-1 in the cavernous body blood evaluated 30 minutes after injection of prostaglandin E1 did not show any difference compared to peripheral venous concentration of the peptide in the 2 patient groups. Concentrations of endothelin-1 in the peripheral vein and the cavernous body blood were not different in patients with a full erection compared with incomplete penis erection after injection of prostaglandin E1 in the cavernous body.

Topics: Adult; Diabetes Complications; Diabetes Mellitus; Endothelin-1; Erectile Dysfunction; Humans; Male; Middle Aged

1. The obese fa/fa Zucker rat is a genetic model of obesity and insulin resistance which develops a number of metabolic and endocrine features of non-insulin-dependent diabetes, including hypertension, proteinuria and glomerular sclerosis. 2. We have investigated the urinary excretion of the metabolites of thromboxane (thromboxane B2) and prostacyclin (6-keto prostaglandin F1 alpha), and of endothelin and cyclic GMP as markers for changes in the balance of renal haemodynamic factors in the obese Zucker rat. 3. Obese fa/fa Zucker rats were hypertensive compared with their lean counterparts (161 +/- 3 and 138 +/- 3 mmHg respectively, P < 0.01); obese animals were also markedly proteinuric (16.7 +/- 6.7 versus 1.1 +/- 0.1 mg/ml) and albuminuric (8.3 +/- 2.9 versus 0.4 +/- 0.25 mg/ml) and excreted less creatinine than lean animals (all P < 0.01). Urinary excretion of endothelin was greater in obese rats (123 +/- 24 versus 62 +/- 10 pg/15 h, P < 0.05) as was the level of pre-proendothelin mRNA, but excretion of cyclic GMP was depressed (12.5 +/- 1.6 versus 27.2 +/- 3.1 nmol/ 15 h, P < 0.01). Histological examination of kidneys from obese animals showed evidence of focal glomerulosclerosis and cortical tubular damage. 4. These results show that increased urinary endothelin is associated with proteinuria and early stage nephropathy in this animal model of non-insulin-dependent diabetes mellitus. This finding, coupled with a decreased excretion of cyclic GMP, suggests that these increased renal vasoconstrictor/vasodilator forces might contribute to the renal functional changes in non-insulin-dependent diabetes mellitus.

Topics: 6-Ketoprostaglandin F1 alpha; Albuminuria; Animals; Cyclic GMP; Diabetes Mellitus; Diabetes Mellitus, Type 2; Endothelin-1; Immunohistochemistry; Kidney; Male; Obesity; Rats; Rats, Zucker; RNA, Messenger; Statistics, Nonparametric; Thromboxane B2

The goal of these studies was to examine endothelin-1 (ET-1)-induced modulation of contractile responses elicited by the selective alpha 1-adrenergic agonist, phenylephrine (PE), on isolated human corporal tissue strips. Pharmacological studies were conducted on human corporal tissue strips obtained from 22 patients undergoing implantation of penile prostheses for erectile dysfunction. For the purposes of statistical analysis, the patients were stratified into two age groups: A, age < or = 59 y (n = 10) and B, age > or = 60 y (n = 12). The patients were further sub-divided into two diagnostic categories, diabetics (DM, n = 9) and nondiabetics (ND, n = 13). Cumulative concentration-response curves (CRCs) were constructed to the alpha 1-adrenergic agonist, PE, prior to constructing a CRC to a single mixture of PE and ET-1 on the same tissue. A previously described fixed molar ratio (FMR) protocol was used to generate CRCs to mixtures of PE and ET-1. In all cases, for the PE:ET-1 FMRs of 90:10, 80:20 and 70:30, the partial substitution of PE with ET-1 resulted in an approx 3-fold leftward shift in the EC50 of the PE alone CRC with an approx 4% concomitant increase in Emax and a decrease in the slope factor value. There were no significant age- or disease-related differences in any of the logistic parameter estimates that describe the FMR CRC, indicating that there are no detectable age- or disease-related alterations in ET-1-induced amplification of alpha 1-adrenergic-mediated contractions in these studies. In addition, the location of the FMR CRC was precisely predicted by the theoretical CRC for simple additivity of agonist effects. In conclusion, since relatively small increases in ET-1 concentrations were associated with significant increases in alpha 1-adrenergic-mediated contractile responses, these data provide further testimony to the importance of ET-1 in modulating corporal smooth muscle tone, and moreover, establish a conceptual framework for understanding the mechanism of its action(s).

Topics: Adrenergic alpha-1 Receptor Agonists; Adrenergic alpha-Agonists; Aged; Diabetes Complications; Diabetes Mellitus; Endothelin-1; Humans; In Vitro Techniques; Male; Middle Aged; Muscle Contraction; Muscle, Smooth; Penis; Phenylephrine; Receptors, Endothelin