Endothelin, a peptide inhibitor of Na(+)-K(+)-ATPase in intact renaltubular epithelial cells

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Zeidel, M.L.; Brady, H.R.; Kone, B.C.; Gullans, S.R. (Brigham and Women' s Hospital, Boston, MA (USA))

1989-12-01

Endothelin, a potent vasoconstrictor released by vascular endothelial cells, can induce natriuresis in vivo. These studies examined the regulation of Na+ transport by endothelin in suspensions of rabbit proximal tubule (PT) and inner medullary collecting duct (IMCD) cells. Endothelin reduced oxygen consumption (QO2) by 18 +/- 1% in IMCD cells but did not alter QO2 in PT cells. In IMCD cells, endothelin inhibited QO2 half maximally at approximately 5 x 10(-12) M. Several lines of evidence indicate that endothelin reduces QO2 by inhibiting the Na(+)-K(+)-ATPase. (1) Endothelin gave no further inhibition of QO2 after ouabain and blunted the stimulatory effect of amphotericin B on QO2 (+29 +/- 4% in absence of endothelin, 0 +/- 5% in presence of endothelin; n = 6 preparations, P less than 0.001). (2) Endothelin inhibited ouabain-sensitive 86Rb+ uptake by 46.6 +/- 8.6% at 10 s and by 35.4 +/- 5.3% at 30 s without altering uptake at (60 min. 3) Addition of endothelin to IMCD cells induced a net K+ efflux with an initial rate of 32.2 +/- 4.8 nmol.min-1.mg protein-1, consistent with inhibition of the Na(+)-K(+)-ATPase. In contrast to the response observed in intact cells, in permeabilized IMCD cells endothelin did not inhibit ouabain-sensitive ATPase. Several observations indicated that prostaglandin E2 (PGE2) mediates endothelin inhibition of Na(+)-K(+)-ATPase activity. (1) The response to endothelin was blocked by ibuprofen in assays of QO2, net K+ flux, and 86Rb+ uptake. (2) Endothelin and PGE2 gave equivalent, nonadditive inhibition of ouabain-sensitive 86Rb+ uptake.

Endothelin, a peptide inhibitor of Na(+)-K(+)-ATPase in intact renaltubular epithelial cells

International Nuclear Information System (INIS)

Zeidel, M.L.; Brady, H.R.; Kone, B.C.; Gullans, S.R.

1989-01-01

Endothelin, a potent vasoconstrictor released by vascular endothelial cells, can induce natriuresis in vivo. These studies examined the regulation of Na+ transport by endothelin in suspensions of rabbit proximal tubule (PT) and inner medullary collecting duct (IMCD) cells. Endothelin reduced oxygen consumption (QO2) by 18 +/- 1% in IMCD cells but did not alter QO2 in PT cells. In IMCD cells, endothelin inhibited QO2 half maximally at approximately 5 x 10(-12) M. Several lines of evidence indicate that endothelin reduces QO2 by inhibiting the Na(+)-K(+)-ATPase. (1) Endothelin gave no further inhibition of QO2 after ouabain and blunted the stimulatory effect of amphotericin B on QO2 (+29 +/- 4% in absence of endothelin, 0 +/- 5% in presence of endothelin; n = 6 preparations, P less than 0.001). (2) Endothelin inhibited ouabain-sensitive 86Rb+ uptake by 46.6 +/- 8.6% at 10 s and by 35.4 +/- 5.3% at 30 s without altering uptake at (60 min. 3) Addition of endothelin to IMCD cells induced a net K+ efflux with an initial rate of 32.2 +/- 4.8 nmol.min-1.mg protein-1, consistent with inhibition of the Na(+)-K(+)-ATPase. In contrast to the response observed in intact cells, in permeabilized IMCD cells endothelin did not inhibit ouabain-sensitive ATPase. Several observations indicated that prostaglandin E2 (PGE2) mediates endothelin inhibition of Na(+)-K(+)-ATPase activity. (1) The response to endothelin was blocked by ibuprofen in assays of QO2, net K+ flux, and 86Rb+ uptake. (2) Endothelin and PGE2 gave equivalent, nonadditive inhibition of ouabain-sensitive 86Rb+ uptake

Upregulation of endothelin ETB receptor-mediated vasoconstriction in rat coronary artery after organ culture

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Eskesen, Karen; Edvinsson, Lars

2006-01-01

The aim of this study was to examine if endothelin ET(B) receptor-mediated contraction occurred in isolated segments of rat coronary arteries during organ culture. Presence of contractile endothelin ET(B) receptors was studied by measuring the change in isometric tension in rings of left anterior......(+)-solution was not modified after 1 day in culture medium. The experiments indicate that organ culture of rat coronary arteries upregulate endothelin ET(B) receptor-mediated contraction by inducing synthesis of new protein....... descending coronary arteries isolated from hearts of rats as response to application of the selective endothelin ET(B) receptor agonist, Sarafotoxin 6c and endothelin-1. In segments cultured 1 day in serum free Dulbecco's Modified Eagle's Medium, Sarafotoxin 6c induced a concentration dependent contraction...

Endothelin-1 Regulation of exercise-induced changes in flow: Dynamic regulation of vascular tone

NARCIS (Netherlands)

Rapoport, R.M. (Robert M.); D. Merkus (Daphne)

2017-01-01

textabstractAlthough endothelin (ET)-1 is a highly potent vasoconstrictor with considerable efficacy in numerous vascular beds, the role of endogenous ET-1 in the regulation of vascular tone remains unclear. The perspective that ET-1 plays little role in the on-going regulation of vascular tone at

Venous plasma levels of endothelin-1 are not altered immediately after nitroglycerin infusion in healthy subjects

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Thomsen, L L; Iversen, Helle Klingenberg; Emmeluth, C

1995-01-01

before and immediately (5-30 s) after 80 min infusion of NTG (glyceryl trinitrate) or saline in 12 healthy subjects. On two different days separated by at least 1 week, NTG in four different doses, 0.015, 0.25, 1.0, and 2.0 micrograms. kg-1. min-1, or placebo (isotonic saline) was infused successively...... for 20 min each dose. During the infusion blood pressure and heart rate were measured. NTG infusion significantly decreased systolic blood pressure from 112.4 to 103.4 mmHg and pulse pressure from 39.3 to 29.5 mmHg. Heart rate increased from 62.7 to 73.1 beats. min-1. No changes in endothelin-1 plasma...... levels were induced by NTG infusion (2.4 pg.ml-1 before NTG vs. 2.7 pg.ml-1 after NTG) and placebo infusion also did not affect plasma endothelin-1. It is concluded that venous plasma levels of endothelin-1 are not altered immediately after NTG infusion....

Different pressor and bronchoconstrictor properties of human big-endothelin-1, 2 (1-38) and 3 in ketamine/xylazine-anaesthetized guinea-pigs.

OpenAIRE

Gratton, J P; Rae, G A; Claing, A; Télémaque, S; D'Orléans-Juste, P

1995-01-01

1. In the present study, the precursors of endothelin-1, endothelin-2 and endothelin-3 were tested for their pressor and bronchoconstrictor properties in the anaesthetized guinea-pig. In addition, the effects of big-endothelin-1 and endothelin-1 were assessed under urethane or ketamine/xylazine anaesthesia. 2. When compared to ketamine/xylazine, urethane markedly depressed the pressor and bronchoconstrictor properties of endothelin-1 and big-endothelin-1. 3. Under ketamine/xylazine anaesthesi...

Neurosensory changes in a human model of endothelin-1 induced pain: a behavioral study

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Hans, Guy; Deseure, Kristof; Robert, Dominique; de Hert, Stefan

2007-01-01

Although pain is a frequent feature in patients with cancer, its etiology is still poorly understood. In recent years, endothelin-1 (ET-1) has become a major target molecule in the etiology of cancer pain. In this randomised, double-blind study the effects of intradermal injection of ET-1 on

Effects of a Single Dose of Erythropoietin on Motor Function and Cognition after Focal Brain Ischemia in Adult Rats

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Michaela Hralová

2014-01-01

Full Text Available We tested the influence of erythropoietin (EPO, a basic cytokine in erythropoiesis regulation, on the process of motor function and cognition after focal brain ischemia induced by a local application of endothelin. Endothelin-1 (ET-1 induced short lasting strong vasoconstriction, with described impact on the structure and on the function of neuronal cells. Neurological description of motor function and Morris water maze test (the swimming test is one of most widely used methods for studying cognitive functions in rodents were used to study the process of learning and memory in three-month-old male albino Wistar rats (n=52. Both tests were performed one week before, and three weeks after ischemia induction (endothelin application on the cortex in the area of a. cerebri media dx.. Experimental group received i.p. injection of EPO (5,000 IU/kg body weight, 10 min before endothelin application. Control group of animals received one i.p. injection of saline at the dose of 1 ml/kg body weight at the same time. Only sham surgery was performed in the third group of animals. Rats with EPO pretreatment before the experimental lesion exhibited significantly better motor and cognitive function then those with saline injection. No significant changes in the motor and cognitive function were found in the third group of rats (sham operated controls.

Enhanced expression of contractile endothelin ET(B) receptors in rat coronary artery after organ culture

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Johnsson, E.; Maddahi, A.; Wackenfors, A.

2008-01-01

. In cardiovascular disease and in organ culture in vitro, endothelin ET(B) receptors are up-regulated on smooth muscle cells. The objectives of the present study were to characterise the endothelin receptor-induced vasoconstriction and quantify the endothelin receptor mRNA levels and immunoreactivity in fresh...... and cultured rat coronary arteries. We demonstrate that endothelin-1 induces strong and equal concentration-dependent contractions in fresh and cultured segments from the left anterior descending coronary artery. Sarafotoxin 6c, an endothelin ET(B) receptor agonist, had negligible effect in fresh arteries...... but produced significant vasoconstriction after organ culture. The endothelin ET(B) receptor mRNA level and the receptor protein immunoreactivity were increased, whereas the level of endothelin ET(A) receptor mRNA was down-regulated but not its receptor protein immunoreactivity after organ culture...

Endothelin-1 Regulation of Exercise-Induced Changes in Flow: Dynamic Regulation of Vascular Tone

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Robert M. Rapoport

2017-10-01

Full Text Available Although endothelin (ET-1 is a highly potent vasoconstrictor with considerable efficacy in numerous vascular beds, the role of endogenous ET-1 in the regulation of vascular tone remains unclear. The perspective that ET-1 plays little role in the on-going regulation of vascular tone at least under physiologic conditions is supported by findings that potential ET-1 constriction is minimized by the release of the vasodilator and ET-1 synthesis inhibitor, nitric oxide (NO. Indeed, ET-1 release and constriction is self-limited by ET-1-induced, endothelial ETB receptor-mediated release of NO. Moreover, even if the balance between ET-1 and NO were reversed as the result of lowered NO activity, as occurs in a number of pathophysiologies associated with endothelial dysfunction, the well-known resistance of ET-1 constriction to reversal (as determined with exogenous ET-1 precludes ET-1 in the dynamic, i.e., moment-to-moment, regulation of vascular tone. On the other hand, and as presently reviewed, findings of ET-1-dependent modulation of organ blood flow with exercise under physiologic conditions demonstrate the dynamic regulation of vascular tone by ET-1. We speculate that this regulation is mediated at least in part through changes in ET-1 synthesis/release caused by pulsatile flow-induced shear stress and NO.

Airborne fine particulate matter induces an upregulation of endothelin receptors on rat bronchi

International Nuclear Information System (INIS)

Wang, Rong; Xiao, Xue; Cao, Lei; Shen, Zhen-xing; Lei, Ying; Cao, Yong-xiao

2016-01-01

Airborne fine particulate matter (PM2.5) is a risk factor for respiratory diseases. However, little is known about the effects of PM2.5 on bronchi. The present study investigated the effect of airborne PM2.5 on rat bronchi and the underlying mechanisms. Isolated rat bronchial segments were cultured for 24 h. Endothelin (ET) receptor-mediated contractile responses were recorded using a wire myograph. The mRNA and protein expression levels of ET receptors were studied using quantitative real-time PCR, Western blotting, and immunohistochemistry. The results demonstrated that ET A and ET B receptor agonists induced remarkable contractile responses on fresh and cultured bronchial segments. PM2.5 (1.0 or 3.0 μg/ml) significantly enhanced ET A and ET B receptor-mediated contractile responses in bronchi with a markedly increased maximal contraction compared to the DMSO or fresh groups. PM2.5 increased the mRNA and protein expression levels of ET A and ET B receptors. U0126 (a MEK1/2 inhibitor) and SB203580 (a p38 inhibitor) significantly suppressed PM2.5-induced increases in ET B receptor-mediated contractile responses, mRNA and protein levels. SP600125 (a JNK inhibitor) and SB203580 significantly abrogated the PM2.5-induced enhancement of ET A receptor-mediated contraction and receptor expression. In conclusion, PM2.5 upregulates ET receptors in bronchi. ET B receptor upregulation is associated with MEK1/2 and p38 pathways, and the upregulation of ET A receptor is involved in JNK and p38 pathways. - Highlights: • Airborne PM2.5 induces bronchial hyperreactivity mediated with endothelin ET B and ET A receptors in rats. • PM2.5 increases mRNA and protein expressions of endothelin ET B and ET A receptors in bronchi. • The upregulation of ET B receptor is associated with MEK1/2 and p38 pathways. • The upregulation of ET A receptor is involved in JNK and p38 pathways. • The research provides novel understanding for PM2.5-associated respiratory diseases.

Impact of endothelin blockade on acute exercise-induced changes in blood flow and endothelial function in type 2 diabetes mellitus.

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Schreuder, Tim H A; van Lotringen, Jaap H; Hopman, Maria T E; Thijssen, Dick H J

2014-09-01

Positive vascular effects of exercise training are mediated by acute increases in blood flow. Type 2 diabetes patients show attenuated exercise-induced increases in blood flow, possibly mediated by the endothelin pathway, preventing an optimal stimulus for vascular adaptation. We examined the impact of endothelin receptor blockade (bosentan) on exercise-induced blood flow in the brachial artery and on pre- and postexercise endothelial function in type 2 diabetes patients (n = 9, 60 ± 7 years old) and control subjects (n = 10, 60 ± 5 years old). Subjects reported twice to the laboratory to perform hand-grip exercise in the presence of endothelin receptor blockade or placebo. We examined brachial artery endothelial function (via flow-mediated dilatation) before and after exercise, as well as blood flow during exercise. Endothelin receptor blockade resulted in a larger increase in blood flow during exercise in type 2 diabetes patients (P = 0.046), but not in control subjects (P = 0.309). Exercise increased shear rate across the exercise protocol, unaffected by endothelin receptor blockade. Exercise did not alter brachial artery diameter in either group, but endothelin receptor blockade resulted in a larger brachial artery diameter in type 2 diabetes patients (P = 0.033). Exercise significantly increased brachial artery flow-mediated dilatation in both groups, unaffected by endothelin receptor blockade. Endothelin receptor blockade increased exercise-induced brachial artery blood flow in type 2 diabetes patients, but not in control subjects. Despite this effect of endothelin receptor blockade on blood flow, we found no impact on baseline or post-exercise endothelial function in type 2 diabetes patients or control subjects, possibly related to normalization of the shear stimulus during exercise. The successful increase in blood flow during exercise in type 2 diabetes patients through endothelin receptor blockade may have beneficial effects in

Low density lipoprotein induces upregulation of vasoconstrictive endothelin type B receptor expression

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Xu, Cang-Bao; Zheng, Jian-Pu; Zhang, Wei

2014-01-01

Vasoconstrictive endothelin type B (ET(B)) receptors promote vasospasm and ischemic cerebro- and cardiovascular diseases. The present study was designed to examine if low density lipoprotein (LDL) induces upregulation of vasoconstrictive ET(B) receptor expression and if extracellular signal...

Endothelin receptor a blockade is an ineffective treatment for adriamycin nephropathy.

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Roderick J Tan

Full Text Available Endothelin is a vasoconstricting peptide that plays a key role in vascular homeostasis, exerting its biologic effects via two receptors, the endothelin receptor A (ETA and endothelin receptor B (ETB. Activation of ETA and ETB has opposing actions, in which hyperactive ETA is generally vasoconstrictive and pathologic. Selective ETA blockade has been shown to be beneficial in renal injuries such as diabetic nephropathy and can improve proteinuria. Atrasentan is a selective pharmacologic ETA blocker that preferentially inhibits ETA activation. In this study, we evaluated the efficacy of ETA blockade by atrasentan in ameliorating proteinuria and kidney injury in murine adriamycin nephropathy, a model of human focal segmental glomerulosclerosis. We found that ETA expression was unaltered during the course of adriamycin nephropathy. Whether initiated prior to injury in a prevention protocol (5 mg/kg/day, i.p. or after injury onset in a therapeutic protocol (7 mg/kg or 20 mg/kg three times a week, i.p., atrasentan did not significantly affect the initiation and progression of adriamycin-induced albuminuria (as measured by urinary albumin-to-creatinine ratios. Indices of glomerular damage were also not improved in atrasentan-treated groups, in either the prevention or therapeutic protocols. Atrasentan also failed to improve kidney function as determined by serum creatinine, histologic damage, and mRNA expression of numerous fibrosis-related genes such as collagen-I and TGF-β1. Therefore, we conclude that selective blockade of ETA by atrasentan has no effect on preventing or ameliorating proteinuria and kidney injury in adriamycin nephropathy.

Endothelin-1 and endothelin-3 in cirrhosis: relations to systemic and splanchnic haemodynamics

DEFF Research Database (Denmark)

Møller, Søren; Gülberg, V; Henriksen, Jens Henrik

1995-01-01

correlated with the hepatic venous pressure gradient (r = 0.61, p r = 0.35, p r = -0.31, p r = -0.41, p r = -0.56, p ... correlated to the cardiac output in the group with cirrhosis (r = 0.35, p ....002). The same pattern was found in arterial endothelin-3. Hepatic venous endothelin-3 correlated significantly with central and arterial blood volume (r = 0.56, p

High endothelin-converting enzyme-1 expression independently predicts poor survival of patients with esophageal squamous cell carcinoma.

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Wu, Ching-Fang; Lee, Ching-Tai; Kuo, Yao-Hung; Chen, Tzu-Haw; Chang, Chi-Yang; Chang, I-Wei; Wang, Wen-Lun

2017-09-01

Patients with esophageal squamous cell carcinoma have poor survival and high recurrence rate, thus an effective prognostic biomarker is needed. Endothelin-converting enzyme-1 is responsible for biosynthesis of endothelin-1, which promotes growth and invasion of human cancers. The role of endothelin-converting enzyme-1 in esophageal squamous cell carcinoma is still unknown. Therefore, this study investigated the significance of endothelin-converting enzyme-1 expression in esophageal squamous cell carcinoma clinically. We enrolled patients with esophageal squamous cell carcinoma who provided pretreated tumor tissues. Tumor endothelin-converting enzyme-1 expression was evaluated by immunohistochemistry and was defined as either low or high expression. Then we evaluated whether tumor endothelin-converting enzyme-1 expression had any association with clinicopathological findings or predicted survival of patients with esophageal squamous cell carcinoma. Overall, 54 of 99 patients with esophageal squamous cell carcinoma had high tumor endothelin-converting enzyme-1 expression, which was significantly associated with lymph node metastasis ( p = 0.04). In addition, tumor endothelin-converting enzyme-1 expression independently predicted survival of patients with esophageal squamous cell carcinoma, and the 5-year survival was poorer in patients with high tumor endothelin-converting enzyme-1 expression ( p = 0.016). Among patients with locally advanced and potentially resectable esophageal squamous cell carcinoma (stage II and III), 5-year survival was poorer with high tumor endothelin-converting enzyme-1 expression ( p = 0.003). High tumor endothelin-converting enzyme-1 expression also significantly predicted poorer survival of patients in this population. In patients with esophageal squamous cell carcinoma, high tumor endothelin-converting enzyme-1 expression might indicate high tumor invasive property. Therefore, tumor endothelin-converting enzyme-1 expression

Significance of the Melanocortin 1 and Endothelin B Receptors in Melanocyte Homeostasis and Prevention of Sun-Induced Genotoxicity

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Zalfa A. Abdel-Malek

2016-08-01

Full Text Available The membrane bound melanocortin 1 receptor (MC1R, and the endothelin B receptor (ENDBR are two G-protein coupled receptors that play important roles in constitutive regulation of melanocytes and their response to ultraviolet radiation (UVR, the main etiological factor for melanoma. The human MC1R is a Gs protein-coupled receptor, which is activated by its agonists α-melanocyte stimulating hormone (α-melanocortin; α-MSH and adrenocorticotropic hormone (ACTH. The ENDBR is a Gq coupled-receptor, which is activated by Endothelin (ET-3 during embryonic development, and ET-1 postnatally. Pigmentation and the DNA repair capacity are two major factors that determine the risk for melanoma. Activation of the MC1R by its agonists stimulates the synthesis of eumelanin, the dark brown photoprotective pigment. In vitro studies showed that α-MSH and ET-1 interact synergistically in the presence of basic fibroblast growth factor (bFGF to stimulate human melanocyte proliferation and melanogenesis, and to inhibit UVR-induced apoptosis. An important function of the MC1R is reduction of oxidative stress and activation of DNA repair pathways. The human MC1R is highly polymorphic, and MC1R variants, particularly those that cause loss of function of the expressed receptor, are associated with increased melanoma risk independently of pigmentation. These variants compromise the DNA repair and antioxidant capacities of human melanocytes. Recently, activation of ENDBR by ET-1 was reported to reduce the induction and enhance the repair of UVR-induced DNA photoproducts. We conclude that α-MSH and ET-1 and their cognate receptors MC1R and ENDBR reduce the risk for melanoma by maintaining genomic stability of melanocytes via modulating the DNA damage response to solar UVR. Elucidating the response of melanocytes to UVR should improve our understanding of the process of melanomagenesis, and lead to effective melanoma chemoprevention, as well as therapeutic strategies.

Endothelin-1 and antiangiogenesis

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S. Lankhorst (Stephanie); A.H.J. Danser (Jan); A.H. van den Meiracker (Anton)

2016-01-01

textabstractAntiangiogenesis, targeting vascular endothelial growth factor (VEGF), has become a well-established treatment for patients with cancer. This treatment is associated with nitric oxide (NO) suppression and a dose-dependent activation of the endothelin system, resulting in

Inhibitory effect of fentanyl citrate on the release of endothlin-1 induced by bradykinin in melanoma cells.

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Andoh, Tsugunobu; Shinohara, Akira; Kuraishi, Yasushi

2017-02-01

Our previous study showed that the μ-opioid receptor agonist fentanyl citrate inhibits endothelin-1-and bradykinin-mediated pain responses in mice orthotopically inoculated with melanoma cells. We also demonstrated that bradykinin induces endothelin-1 secretion in melanoma cells. However, the analgesic mechanisms of fentanyl citrate remain unclear. Thus, the present study was conducted to determine whether fentanyl citrate affects bradykinin-induced endothelin-1 secretion in B16-BL6 melanoma cells. The amount of endothelin-1 in the culture medium was measured using an enzyme immunoassay. The expression of endothelin-1, kinin B 2 receptors, and μ-opioid receptors in B16-BL/6 melanoma cells was determined using immunocytochemistry. Fentanyl citrate inhibited bradykinin-induced endothelin-1 secretion. The inhibitory effect of fentanyl citrate on the secretion of endothelin-1 was attenuated by the μ-opioid receptor antagonist naloxone methiodide. The immunoreactivities of endothelin-1, kinin B 2 receptors, and μ-opioid receptors in B16-BL6 melanoma cells were observed. These results suggest that fentanyl citrate regulates bradykinin-induced endothelin-1 secretion through μ-opioid receptors in melanoma cells. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

The inhibition of the potassium channel TASK-1 in rat cardiac muscle by endothelin-1 is mediated by phospholipase C.

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Schiekel, Julia; Lindner, Moritz; Hetzel, Andrea; Wemhöner, Konstantin; Renigunta, Vijay; Schlichthörl, Günter; Decher, Niels; Oliver, Dominik; Daut, Jürgen

2013-01-01

The two-pore-domain potassium channel TASK-1 is robustly inhibited by the activation of receptors coupled to the Gα(q) subgroup of G-proteins, but the signal transduction pathway is still unclear. We have studied the mechanisms by which endothelin receptors inhibit the current carried by TASK-1 channels (I(TASK)) in cardiomyocytes. Patch-clamp measurements were carried out in isolated rat cardiomyocytes. I(TASK) was identified by extracellular acidification to pH 6.0 and by the application of the TASK-1 blockers A293 and A1899. Endothelin-1 completely inhibited I(TASK) with an EC(50) of Application of 20 nM endothelin-1 caused a significant increase in action potential duration under control conditions; this was significantly reduced after pre-incubation of the cardiomyocytes with 200 nM A1899. The inhibition of I(TASK) by endothelin-1 was not affected by inhibitors of protein kinase C or rho kinase, but was strongly reduced by U73122, an inhibitor of phospholipase C (PLC). The ability of endothelin-1 to activate PLC-mediated signalling pathways was examined in mammalian cells transfected with TASK-1 and the endothelin-A receptor using patch-clamp measurements and total internal reflection microscopy. U73122 prevented the inhibition of I(TASK) by endothelin-1 and blocked PLC-mediated signalling, as verified with a fluorescent probe for phosphatidylinositol-(4,5)-bisphosphate hydrolysis. Our results show that I(TASK) in rat cardiomyocytes is controlled by endothelin-1 and suggest that the inhibition of TASK-1 via endothelin receptors is mediated by the activation of PLC. The prolongation of the action potential observed with 20 nM endothelin-1 was mainly due to the inhibition of I(TASK).

Gestational hypoxia induces preeclampsia-like symptoms via heightened endothelin-1 signaling in pregnant rats.

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Zhou, Jianjun; Xiao, Daliao; Hu, Yali; Wang, Zhiqun; Paradis, Alexandra; Mata-Greenwood, Eugenia; Zhang, Lubo

2013-09-01

Preeclampsia is a life-threatening pregnancy disorder. However, its pathogenesis remains unclear. We tested the hypothesis that gestational hypoxia induces preeclampsia-like symptoms via heightened endothelin-1 (ET-1) signaling. Time-dated pregnant and nonpregnant rats were divided into normoxic and hypoxic (10.5% O2 from the gestational day 6-21) groups. Chronic hypoxia had no significant effect on blood pressure or proteinuria in nonpregnant rats but significantly increased blood pressure on day 12 (systolic blood pressure, 111.7 ± 6.1 versus 138.5 ± 3.5 mm Hg; P=0.004) and day 20 (systolic blood pressure, 103.4 ± 4.6 versus 125.1 ± 6.1 mm Hg; P=0.02) in pregnant rats and urine protein (μg/μL)/creatinine (nmol/μL) ratio on day 20 (0.10 ± 0.01 versus 0.20 ± 0.04; P=0.04), as compared with the normoxic control group. This was accompanied with asymmetrical fetal growth restriction. Hypoxia resulted in impaired trophoblast invasion and uteroplacental vascular remodeling. In addition, plasma ET-1 levels, as well as the abundance of prepro-ET-1 mRNA, ET-1 type A receptor and angiotensin II type 1 receptor protein in the kidney and placenta were significantly increased in the chronic hypoxic group, as compared with the control animals. Treatment with the ET-1 type A receptor antagonist, BQ123, during the course of hypoxia exposure significantly attenuated the hypoxia-induced hypertension and other preeclampsia-like features. The results demonstrate that chronic hypoxia during gestation induces preeclamptic symptoms in pregnant rats via heightened ET-1 and ET-1 type A receptor-mediated signaling, providing a molecular mechanism linking gestational hypoxia and increased risk of preeclampsia.

The insulinotropic effect of endothelin-1 is mediated by glucagon release from the islet alpha cells

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Brock, B; Gregersen, S; Kristensen, K

1999-01-01

AIMS/HYPOTHESIS: The circulating concentrations of endothelin-1 (ET-1), a peptide derived from endothelium, are increased in hypertension and diabetes. Endothelin-1 has recently been shown to be an insulinotropic agent. The mechanism of action of endothelin-1 on the endocrine pancreas has not yet...... been clarified. METHODS: We investigated the action of endothelin-1 on the insulin secretion, the binding of (125)I-ET-1 to beta cells as well as its effects on purified beta and non-beta cells from normal rats. The expression of endothelin receptors in alpha- and beta-cell lines and in normal rat...... from purified beta cells. Endothelin-1-(100 nmol/l) increased, however, both insulin and glucagon secretion from a mixture of purified beta and non-beta cells indicating that alpha cells seem to have a key role for the action of ET-1 on insulin secretion. CONCLUSION/INTERPRETATION: The insulinotropic...

UVB radiation generates sunburn pain and affects skin by activating epidermal TRPV4 ion channels and triggering endothelin-1 signaling.

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Moore, Carlene; Cevikbas, Ferda; Pasolli, H Amalia; Chen, Yong; Kong, Wei; Kempkes, Cordula; Parekh, Puja; Lee, Suk Hee; Kontchou, Nelly-Ange; Yeh, Iwei; Ye, Iwei; Jokerst, Nan Marie; Fuchs, Elaine; Steinhoff, Martin; Liedtke, Wolfgang B

2013-08-20

At our body surface, the epidermis absorbs UV radiation. UV overexposure leads to sunburn with tissue injury and pain. To understand how, we focus on TRPV4, a nonselective cation channel highly expressed in epithelial skin cells and known to function in sensory transduction, a property shared with other transient receptor potential channels. We show that following UVB exposure mice with induced Trpv4 deletions, specifically in keratinocytes, are less sensitive to noxious thermal and mechanical stimuli than control animals. Exploring the mechanism, we find that epidermal TRPV4 orchestrates UVB-evoked skin tissue damage and increased expression of the proalgesic/algogenic mediator endothelin-1. In culture, UVB causes a direct, TRPV4-dependent Ca(2+) response in keratinocytes. In mice, topical treatment with a TRPV4-selective inhibitor decreases UVB-evoked pain behavior, epidermal tissue damage, and endothelin-1 expression. In humans, sunburn enhances epidermal expression of TRPV4 and endothelin-1, underscoring the potential of keratinocyte-derived TRPV4 as a therapeutic target for UVB-induced sunburn, in particular pain.

Elevated plasma endothelin-1 and pulmonary arterial pressure in children exposed to air pollution.

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Calderón-Garcidueñas, Lilian; Vincent, Renaud; Mora-Tiscareño, Antonieta; Franco-Lira, Maricela; Henríquez-Roldán, Carlos; Barragán-Mejía, Gerardo; Garrido-García, Luis; Camacho-Reyes, Laura; Valencia-Salazar, Gildardo; Paredes, Rogelio; Romero, Lina; Osnaya, Hector; Villarreal-Calderón, Rafael; Torres-Jardón, Ricardo; Hazucha, Milan J; Reed, William

2007-08-01

Controlled exposures of animals and humans to particulate matter (PM) or ozone air pollution cause an increase in plasma levels of endothelin-1, a potent vasoconstrictor that regulates pulmonary arterial pressure. The primary objective of this field study was to determine whether Mexico City children, who are chronically exposed to levels of PM and O(3) that exceed the United States air quality standards, have elevated plasma endothelin-1 levels and pulmonary arterial pressures. We conducted a study of 81 children, 7.9 +/- 1.3 years of age, lifelong residents of either northeast (n = 19) or southwest (n = 40) Mexico City or Polotitlán (n = 22), a control city with PM and O(3) levels below the U.S. air quality standards. Clinical histories, physical examinations, and complete blood counts were done. Plasma endothelin-1 concentrations were determined by immunoassay, and pulmonary arterial pressures were measured by Doppler echocardiography. Mexico City children had higher plasma endothelin-1 concentrations compared with controls (p < 0.001). Mean pulmonary arterial pressure was elevated in children from both northeast (p < 0.001) and southwest (p < 0.05) Mexico City compared with controls. Endothelin-1 levels in Mexico City children were positively correlated with daily outdoor hours (p = 0.012), and 7-day cumulative levels of PM air pollution < 2.5 mum in aerodynamic diameter (PM(2.5)) before endothelin-1 measurement (p = 0.03). Chronic exposure of children to PM(2.5) is associated with increased levels of circulating endothelin-1 and elevated mean pulmonary arterial pressure.

Elevated Plasma Endothelin-1 and Pulmonary Arterial Pressure in Children Exposed to Air Pollution

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Calderón-Garcidueñas, Lilian; Vincent, Renaud; Mora-Tiscareño, Antonieta; Franco-Lira, Maricela; Henríquez-Roldán, Carlos; Barragán-Mejía, Gerardo; Garrido-García, Luis; Camacho-Reyes, Laura; Valencia-Salazar, Gildardo; Paredes, Rogelio; Romero, Lina; Osnaya, Hector; Villarreal-Calderón, Rafael; Torres-Jardón, Ricardo; Hazucha, Milan J.; Reed, William

2007-01-01

Background Controlled exposures of animals and humans to particulate matter (PM) or ozone air pollution cause an increase in plasma levels of endothelin-1, a potent vasoconstrictor that regulates pulmonary arterial pressure. Objectives The primary objective of this field study was to determine whether Mexico City children, who are chronically exposed to levels of PM and O3 that exceed the United States air quality standards, have elevated plasma endothelin-1 levels and pulmonary arterial pressures. Methods We conducted a study of 81 children, 7.9 ± 1.3 years of age, lifelong residents of either northeast (n = 19) or southwest (n = 40) Mexico City or Polotitlán (n = 22), a control city with PM and O3 levels below the U.S. air quality standards. Clinical histories, physical examinations, and complete blood counts were done. Plasma endothelin-1 concentrations were determined by immunoassay, and pulmonary arterial pressures were measured by Doppler echocardiography. Results Mexico City children had higher plasma endothelin-1 concentrations compared with controls (p < 0.001). Mean pulmonary arterial pressure was elevated in children from both northeast (p < 0.001) and southwest (p < 0.05) Mexico City compared with controls. Endothelin-1 levels in Mexico City children were positively correlated with daily outdoor hours (p = 0.012), and 7-day cumulative levels of PM air pollution < 2.5 μm in aerodynamic diameter (PM2.5) before endothelin-1 measurement (p = 0.03). Conclusions Chronic exposure of children to PM2.5 is associated with increased levels of circulating endothelin-1 and elevated mean pulmonary arterial pressure. PMID:17687455

Stimulation of Transforming Growth Factor-β1-Induced Endothelial-To-Mesenchymal Transition and Tissue Fibrosis by Endothelin-1 (ET-1): A Novel Profibrotic Effect of ET-1.

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Wermuth, Peter J; Li, Zhaodong; Mendoza, Fabian A; Jimenez, Sergio A

2016-01-01

TGF-β-induced endothelial-to-mesenchymal transition (EndoMT) is a newly recognized source of profibrotic activated myofibroblasts and has been suggested to play a role in the pathogenesis of various fibrotic processes. Endothelin-1 (ET-1) has been implicated in the development of tissue fibrosis but its participation in TGF-β-induced EndoMT has not been studied. Here we evaluated the role of ET-1 on TGF-β1-induced EndoMT in immunopurified CD31+/CD102+ murine lung microvascular endothelial cells. The expression levels of α-smooth muscle actin (α-SMA), of relevant profibrotic genes, and of various transcription factors involved in the EndoMT process were assessed employing quantitative RT-PCR, immunofluorescence histology and Western blot analysis. TGF-β1 caused potent induction of EndoMT whereas ET-1 alone had a minimal effect. However, ET-1 potentiated TGF-β1-induced EndoMT and TGF-β1-stimulated expression of mesenchymal cell specific and profibrotic genes and proteins. ET-1 also induced expression of the TGF-β receptor 1 and 2 genes, suggesting a plausible autocrine mechanism to potentiate TGF-β-mediated EndoMT and fibrosis. Stimulation of TGF-β1-induced skin and lung fibrosis by ET-1 was confirmed in vivo in an animal model of TGF-β1-induced tissue fibrosis. These results suggest a novel role for ET-1 in the establishment and progression of tissue fibrosis.

Endothelin-1 Mediates Brain Microvascular Dysfunction Leading to Long-Term Cognitive Impairment in a Model of Experimental Cerebral Malaria.

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Brandi D Freeman

2016-03-01

Full Text Available Plasmodium falciparum infection causes a wide spectrum of diseases, including cerebral malaria, a potentially life-threatening encephalopathy. Vasculopathy is thought to contribute to cerebral malaria pathogenesis. The vasoactive compound endothelin-1, a key participant in many inflammatory processes, likely mediates vascular and cognitive dysfunctions in cerebral malaria. We previously demonstrated that C57BL6 mice infected with P. berghei ANKA, our fatal experimental cerebral malaria model, sustained memory loss. Herein, we demonstrate that an endothelin type A receptor (ETA antagonist prevented experimental cerebral malaria-induced neurocognitive impairments and improved survival. ETA antagonism prevented blood-brain barrier disruption and cerebral vasoconstriction during experimental cerebral malaria, and reduced brain endothelial activation, diminishing brain microvascular congestion. Furthermore, exogenous endothelin-1 administration to P. berghei NK65-infected mice, a model generally regarded as a non-cerebral malaria negative control for P. berghei ANKA infection, led to experimental cerebral malaria-like memory deficits. Our data indicate that endothelin-1 is critical in the development of cerebrovascular and cognitive impairments with experimental cerebral malaria. This vasoactive peptide may thus serve as a potential target for adjunctive therapy in the management of cerebral malaria.

Intraportal nicotine infusion in rats decreases hepatic blood flow through endothelin-1 and both endothelin A and endothelin B receptors

International Nuclear Information System (INIS)

Hashimoto, Takashi; Yoneda, Masashi; Shimada, Tadahito; Kurosawa, Mieko; Terano, Akira

2004-01-01

Smoking has been demonstrated to aggravate liver injury. Nicotine, a major pharmacological component of tobacco smoke, affects a multitude of functions. Smoking and nicotine induce synthesis of endothelin (ET)-1. The effect of intraportal infusion of nicotine on hepatic circulation and an involvement of ET-1 and ET receptor in the action of nicotine were investigated in rats. Nicotine (0-100 μg/kg/h) was infused into the portal vein of urethane-anesthetized rats, and changes of hepatic blood flow were evaluated. Intraportal infusion of nicotine dose-dependently decreased hepatic blood flow and increased portal pressure without any alteration of heart rate or arterial blood pressure. This action of intraportal nicotine was completely abolished by pretreatment of ET-1 antibody. Either BQ485 (ET A receptor antagonist) or BQ788 (ET B receptor antagonist) partially reversed the effect of nicotine, and combination of BQ788 and BQ485 completely abolished it. These findings suggest that nicotine inhibits hepatic circulation through ET-1, and ET A and ET B receptor

Andrographolide inhibits hypoxia-induced hypoxia-inducible factor 1α and endothelin 1 expression through the heme oxygenase 1/CO/cGMP/MKP-5 pathways in EA.hy926 cells.

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Lin, Hung-Chih; Su, Shih-Li; Lin, Wan-Chun; Lin, Ai-Hsuan; Yang, Ya-Chen; Lii, Chong-Kuei; Chen, Haw-Wen

2018-03-01

Andrographolide is a potent anti-inflammatory agent found in Andrographis paniculata. Endothelin 1 (ET-1) is an endothelium-derived vasoconstrictor with pro-inflammatory properties secreted in response to hypoxia. Mitogen-activated protein kinase phosphatase 5 (MKP-5) is a dual-specificity phosphatase that dephosphorylates threonine and tyrosine residues of MAPKs. We showed previously that hypoxia-induced HIF-1α expression and ET-1 secretion are dependent on p38 MAPK in EA.hy926 cells. Here, we investigate what role MKP-5 plays in andrographolide's inhibition of hypoxia-induced expression of HIF-1α and ET-1. Hypoxic conditions were created using the hypoxia-mimetic agent CoCl 2 . Andrographolide enhanced HO-1 and MKP-5 expression and cellular cGMP content in addition to inhibiting hypoxia-induced ROS generation. Concomitantly, the HO-1 byproduct CO and the cGMP analogue 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP) increased MKP-5 expression, and pretreatment with CO and 8-Br-cGMP inhibited hypoxia-induced HIF-1α and ET-1 expression. Transfection of HO-1 siRNA or pretreatment with the HO-1 inhibitor ZnPP-9 or 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a specific inhibitor of soluble guanylate cyclase, reduced andrographolide-induced MKP-5 expression. Moreover, silencing MKP-5 or treatment with the phosphatase inhibitor vanadate abrogated andrographolide's suppressing hypoxia-induced p38 MAPK activation and HIF-1α expression. The inhibition of hypoxia-induced HIF-1α and ET-1 expression by andrographolide is likely associated with HO-1/CO/cGMP/MKP-5 pathways, which is involved in inhibiting hypoxia-induced p38 MAPK activation. © 2017 Wiley Periodicals, Inc.

Iontophoresis of endothelin receptor antagonists in rats and men.

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Matthieu Roustit

Full Text Available The treatment of scleroderma-related digital ulcers is challenging. The oral endothelin receptor antagonist (ERA bosentan has been approved but it may induce liver toxicity. The objective of this study was to test whether ERAs bosentan and sitaxentan could be locally delivered using iontophoresis.Cathodal and anodal iontophoresis of bosentan and sitaxentan were performed on anaesthetized rat hindquarters without and during endothelin-1 infusion. Skin blood flow was quantified using laser-Doppler imaging and cutaneous tolerability was assessed. Iontophoresis of sitaxentan (20 min, 20 or 100 µA was subsequently performed on the forearm skin of healthy men (n = 5.In rats neither bosentan nor sitaxentan increased skin blood flux compared to NaCl. When simultaneously infusing endothelin-1, cathodal iontophoresis of sitaxentan increased skin blood flux compared to NaCl (AUC(0-20 were 44032.2 ± 12277 and 14957.5 ± 23818.8 %BL.s, respectively; P = 0.01. In humans, sitaxentan did not significantly increase skin blood flux as compared to NaCl. Iontophoresis of ERAs was well tolerated both in animals and humans.This study shows that cathodal iontophoresis of sitaxentan but not bosentan partially reverses endothelin-induced skin vasoconstriction in rats, suggesting that sitaxentan diffuses into the dermis. However, sitaxentan does not influence basal skin microvascular tone in rats or in humans.

Inflammatory Murine Skin Responses to UV-B Light Are Partially Dependent on Endothelin-1 and Mast Cells

OpenAIRE

Metz, Martin; Lammel, Verena; Gibbs, Bernhard F.; Maurer, Marcus

2006-01-01

Endothelin (ET-1) has been shown to crucially contribute to UV-induced skin responses such as tanning. To test whether ET-1 is also involved in early cutaneous reactions to UV, we assessed ET-1 skin levels in UV-irradiated mice. In correlation with the levels of UV-induced skin inflammation, ET-1 concentrations increased substantially and continually. Moreover, blocking of ET-1 receptors (ETA) resulted in significantly decreased cutaneous inflammation following UV irradiation. When we assesse...

The Association of Endothelin-1 Signaling with Bone Alkaline Phosphatase Expression and Protumorigenic Activities in Canine Osteosarcoma.

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Neumann, Z L; Pondenis, H C; Masyr, A; Byrum, M L; Wycislo, K L; Fan, T M

2015-01-01

Canine osteosarcoma (OS) is an aggressive sarcoma characterized by pathologic skeletal resorption and pulmonary metastases. A number of negative prognostic factors, including bone alkaline phosphatase, have been identified in dogs with OS, but the underlying biologic factors responsible for such observations have not been thoroughly investigated. Endothelin-1-mediated signaling is active during bone repair, and is responsible for osteoblast migration, survival, proliferation, and bone alkaline phosphatase expression. The endothelin-1 signaling axis is active in canine OS cells, and this pathway is utilized by malignant osteoblasts for promoting cellular migration, survival, proliferation, and bone alkaline phosphatase activities. 45 dogs with appendicular OS. The expressions of endothelin-1 and endothelin A receptor were studied in OS cell lines and in samples from spontaneously occurring tumors. Activities mediated by endothelin-1 signaling were investigated by characterizing responses in 3 OS cell lines. In 45 dogs with OS, bone alkaline phosphatase concentrations were correlated with primary tumor osteoproductivity. Canine OS cells express endothelin-1 and endothelin A receptor, and this signaling axis mediates OS migration, survival, proliferation, and bone alkaline phosphatase activities. In OS-bearing dogs, circulating bone alkaline phosphatase activities were positively correlated with primary tumor relative bone mineral densities. Canine OS cells express endothelin-1 and functional endothelin A receptors, with the potential for a protumorigenic signaling loop. Increases in bone alkaline phosphatase activity are associated with osteoblastic OS lesions, and might be an epiphenomenon of active endothelin-1 signaling or excessive osteoproduction within the localized bone microenvironment. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Hypoxia-inducible factor-1α, vascular endothelial growth factor, inducible nitric oxide synthase, and endothelin-1 expression correlates with angiogenesis in congenital heart disease

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Hsin-Ling Yin

2016-07-01

Full Text Available In Taiwan, the average prevalence of congenital heart disease (CHD is 13.08/1000 live births. Most children with CHD die before the age of 5 years; therefore, identifying treatment methods to extend the life of CHD patients is an important issue in clinical practice. The objective of this study is to evaluate the roles of hypoxia-inducible factor-1α (HIF-1α, vascular endothelial growth factor (VEGF, inducible nitric oxide synthase (iNOS, endothelin-1 (ET-1, and CD34 in CHD autopsy cases in comparison with autopsy cases without CHD. The study included 19 autopsy cases, which were divided into the following four groups: acyanotic CHD (n = 11, cyanotic CHD (n = 3, CHD associated with chromosomal abnormalities (n = 3, and complex CHD (n = 2. Heart specimens obtained from 10 autopsy cases without CHD were included as controls. Our results indicated that high percentages of HIF-1α (100%, VEGF (89.5%, iNOS (78.9%, and ET-1 (84.2% expressions were observed in CHD autopsy cases and this was found to be significant. HIF-1α induced by hypoxia could play a potential role in relating downstream gene expressions in CHD patients. Upregulation of VEGF by HIF-1α could play an important role in triggering angiogenesis to protect myocardial cell survival in a hypoxic microenvironment. Therefore, HIF-1α could be a significant prognosis marker in CHD and be a prospective candidate in the development of target therapy in cardiovascular diseases.

Cerebrovascular endothelin-1 hyper-reactivity is associated with transient receptor potential canonical channels 1 and 6 activation and delayed cerebral hypoperfusion after forebrain ischaemia in rats

DEFF Research Database (Denmark)

Johansson, S E; Andersen, X E D R; Hansen, R H

2015-01-01

. METHODS: Experimental forebrain ischaemia was induced in Wistar male rats by a two-vessel occlusion model, and the cerebral blood flow was measured by magnetic resonance imaging two days after reperfusion. In vitro vasoreactivity studies, immunofluorescence and quantitative PCR were performed on cerebral...... in the vascular smooth muscle cells was enhanced and correlated with decreased cerebral blood flow two days after forebrain ischaemia. Furthermore, under conditions when voltage-dependent calcium channels were inhibited, endothelin-1-induced cerebrovascular contraction was enhanced and this enhancement...... was presumably mediated by Ca(2+) influx via upregulated transient receptor potential canonical channels 1 and 6. CONCLUSIONS: Our data demonstrates that endothelin-1-mediated influx of extracellular Ca(2+) activates transient receptor potential canonical channels 1 and 6 in cerebral vascular smooth muscle cells...

Intrahippocampal Injection of Endothelin-1: A New Model of Ischemia-induced Seizures in Immature Rats

Czech Academy of Sciences Publication Activity Database

Tsenov, Grygoriy; Máttéffyová, Adéla; Mareš, Pavel; Otáhal, Jakub; Kubová, Hana

2007-01-01

Roč. 48, Suppl.5 (2007), s. 7-13 ISSN 0013-9580 R&D Projects: GA MŠk(CZ) LC554; GA ČR(CZ) GA305/06/0713; GA ČR(CZ) GD305/03/H148 Institutional research plan: CEZ:AV0Z50110509 Keywords : endothelin-1 * epileptic seizures * immature rats Subject RIV: ED - Physiology Impact factor: 3.569, year: 2007

Endothelin-1 overexpression exacerbates atherosclerosis and induces aortic aneurysms in apolipoprotein E knockout mice.

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Li, Melissa W; Mian, Muhammad Oneeb Rehman; Barhoumi, Tlili; Rehman, Asia; Mann, Koren; Paradis, Pierre; Schiffrin, Ernesto L

2013-10-01

Endothelin (ET)-1 plays a role in vascular reactive oxygen species production and inflammation. ET-1 has been implicated in human atherosclerosis and abdominal aortic aneurysm (AAA) development. ET-1 overexpression exacerbates high-fat diet-induced atherosclerosis in apolipoprotein E(-/-) (Apoe(-/-)) mice. ET-1-induced reactive oxygen species and inflammation may contribute to atherosclerosis progression and AAA development. Eight-week-old male wild-type mice, transgenic mice overexpressing ET-1 selectively in endothelium (eET-1), Apoe(-/-) mice, and eET-1/Apoe(-/-) mice were fed high-fat diet for 8 weeks. eET-1/Apoe(-/-) had a 45% reduction in plasma high-density lipoprotein (P<0.05) and presented ≥ 2-fold more aortic atherosclerotic lesions compared with Apoe(-/-) (P<0.01). AAAs were detected only in eET-1/Apoe(-/-) (8/21; P<0.05). Reactive oxygen species production was increased ≥ 2-fold in perivascular fat, media, or atherosclerotic lesions in the ascending aorta and AAAs of eET-1/Apoe(-/-) compared with Apoe(-/-) (P<0.05). Monocyte/macrophage infiltration was enhanced ≥ 2.5-fold in perivascular fat of ascending aorta and AAAs in eET-1/Apoe(-/-) compared with Apoe(-/-) (P<0.05). CD4(+) T cells were detected almost exclusively in perivascular fat (3/6) and atherosclerotic lesions (5/6) in ascending aorta of eET-1/Apoe(-/-) (P<0.05). The percentage of spleen proinflammatory Ly-6C(hi) monocytes was enhanced 26% by ET-1 overexpression in Apoe(-/-) (P<0.05), and matrix metalloproteinase-2 was increased 2-fold in plaques of eET-1/Apoe(-/-) (P<0.05) compared with Apoe(-/-). ET-1 plays a role in progression of atherosclerosis and AAA formation by decreasing high-density lipoprotein, and increasing oxidative stress, inflammatory cell infiltration, and matrix metalloproteinase-2 in perivascular fat, vascular wall, and atherosclerotic lesions.

The ocular endothelin system: a novel target for the treatment of endotoxin-induced uveitis with bosentan.

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Keles, Sadullah; Halici, Zekai; Atmaca, Hasan Tarik; Yayla, Muhammed; Yildirim, Kenan; Ekinci, Metin; Akpinar, Erol; Altuner, Durdu; Cakici, Ozgur; Bayraktutan, Zafer

2014-05-15

We compared the anti-inflammatory effects of bosentan and dexamethasone in endotoxin-induced uveitis (EIU). Endotoxin-induced uveitis was induced by subcutaneous injection of lipopolysaccharide (LPS, 200 μg) in Wistar rats. Rats were divided randomly into 10 groups (n = 6). Bosentan at doses of 50 and 100 mg/kg were administered orally 1 hour before and 12 hours after LPS injection, and dexamethasone was administered by intraperitoneally 30 minutes before and 30 minutes after LPS injection at a dose of 1 mg/kg. Data were collected at two time points for each control and treatment; animals were killed at either 3 or 24 hours after LPS injection. Histopathologic evaluation and aqueous humour measurements of TNF-α level were performed, and endothelin-1 (ET-1), inducible nitric oxide synthase (iNOS), and endothelin receptor A and B (EDNRA and B) expression were analyzed. The group treated with 100 mg/kg bosentan at 24 hours displayed significantly milder uveitis and fewer inflammatory cells compared to LPS-injected animals, and there were similar findings in the dexamethasone-treated group at 24 hours. The TNF-α levels in the dexamethasone treatment group were lower than those in the LPS-induced uveitis control group (P treatment groups at 3 and 24 hours after LPS administration. Bosentan treatment at doses of 50 and 100 mg/kg significantly decreased iNOS expression compared to LPS-injected animals (P treatment groups was statistically significantly lower than that in the LPS-induced uveitis control group at 3 and 24 hours after LPS administration (P < 0.05). Bosentan reduces intraocular inflammation and has similar effects as dexamethasone in a rat model of EIU. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Activation of either the ETA or the ETB receptors is involved in the development of electrographic seizures following intrahippocampal infusion of the endothelin-1 in immature rats

Czech Academy of Sciences Publication Activity Database

Tsenov, Grygoriy; Vondráková, Kateřina; Otáhal, Jakub; Burchfiel, J.; Kubová, Hana

2015-01-01

Roč. 265, Mar 2015 (2015), s. 40-47 ISSN 0014-4886 R&D Projects: GA ČR(CZ) GPP304/11/P386; GA ČR(CZ) GBP304/12/G069; GA ČR(CZ) GA14-20613S Institutional support: RVO:67985823 Keywords : focal ischemia * endothelin-1 * cerebral blood flow * oxygen saturation * seizures * hippocampus * immature rat * ET receptors Subject RIV: FH - Neurology Impact factor: 4.657, year: 2015

The emerging role of endothelin-1 in the pathogenesis of pre-eclampsia.

Science.gov (United States)

Saleh, Langeza; Verdonk, Koen; Visser, Willy; van den Meiracker, Anton H; Danser, A H Jan

2016-10-01

Pre-eclampsia (PE) is the most frequently encountered medical complication during pregnancy. It is characterized by a rise in systemic vascular resistance with a relatively low cardiac output and hypovolemia, combined with severe proteinuria. Despite the hypovolemia, renin-angiotensin system (RAS) activity is suppressed and aldosterone levels are decreased to the same degree as renin. This suggests that the RAS is not the cause of the hypertension in PE, but rather that its suppression is the consequence of the rise in blood pressure. Abnormal placentation early in pregnancy is widely assumed to be an important initial event in the onset of PE. Eventually, this results in the release of anti-angiogenic factors [in particular, soluble Fms-like tyrosine kinase-1 (sFlt-1)] and cytokines, leading to generalized vascular dysfunction. Elevated sFlt-1 levels bind and inactivate vascular endothelial growth factor (VEGF). Of interest, VEGF inhibition with drugs like sunitinib, applied in cancer patients, results in a PE-like syndrome, characterized by hypertension, proteinuria and renal toxicity. Both in cancer patients treated with sunitinib and in pregnant women with PE, significant rises in endothelin-1 occur. Multiple regression analysis revealed that endothelin-1 is an independent determinant of the hypertension and proteinuria in PE, and additionally a renin suppressor. Moreover, studies in animal models representative of PE, have shown that endothelin receptor blockers prevent the development of this disease. Similarly, endothelin receptor blockers are protective during sunitinib treatment. Taken together, activation of the endothelin system emerges as an important pathway causing the clinical manifestations of PE. This paper critically addresses this concept, taking into consideration both clinical and preclinical data, and simultaneously discusses the therapeutic consequences of this observation. © The Author(s), 2016.

Relaxing Responses to Hydrogen Peroxide and Nitric Oxide in Human Pericardial Resistance Arteries Stimulated with Endothelin-1

DEFF Research Database (Denmark)

Leurgans, Thomas M; Bloksgaard, Maria; Irmukhamedov, Akhmadjon

2018-01-01

In human pericardial resistance arteries, effects of the endothelium-dependent vasodilator bradykinin are mediated by NO during contraction induced by K(+) or the TxA2 analogue U46619 and by H2 O2 during contraction by endothelin-1 (ET-1), respectively. We tested the hypotheses that ET-1 reduces...... also acts as an endothelium-dependent vasodilator. This article is protected by copyright. All rights reserved....

NITRIC OXIDE AND ENDOTHELIN-1 IN CHILDREN WITH DIGESTIVE DISORDERS

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I. V. Panova

2012-01-01

Full Text Available The important part in the group of biological compounds, participating in the regulation of the functions of the gastro-intestinal tract, is assigned to endothelial factors because of their impact on the majority of physiological and pathophysiological processes of the digestive system. The article provides information about physiological role of nitric oxide and endothelin-1 and presents a review of scientific data on the participation of nitric oxide and endothelin-1 in the pathogenesis of many digestive system diseases, emphasizing chronic inflammatory disorders of the upper gastrointestinal tract. The authors accentuate the importance of endothelium endocrine function research in children with esophagogastroduodenal disorders at the beginning of puberty, which is the critical period of ontogenesis.

Role of endothelin-converting enzyme, chymase and neutral endopeptidase in the processing of big ET-1, ET-1(1-21) and ET-1(1-31) in the trachea of allergic mice.

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De Campo, Benjamin A; Goldie, Roy G; Jeng, Arco Y; Henry, Peter J

2002-08-01

The present study examined the roles of endothelin-converting enzyme (ECE), neutral endopeptidase (NEP) and mast cell chymase as processors of the endothelin (ET) analogues ET-1(1-21), ET-1(1-31) and big ET-1 in the trachea of allergic mice. Male CBA/CaH mice were sensitized with ovalbumin (10 microg) delivered intraperitoneal on days 1 and 14, and exposed to aerosolized ovalbumin on days 14, 25, 26 and 27 (OVA mice). Mice were killed and the trachea excised for histological analysis and contraction studies on day 28. Tracheae from OVA mice had 40% more mast cells than vehicle-sensitized mice (sham mice). Ovalbumin (10 microg/ml) induced transient contractions (15+/-3% of the C(max)) in tracheae from OVA mice. The ECE inhibitor CGS35066 (10 microM) inhibited contractions induced by big ET-1 (4.8-fold rightward shift of dose-response curve; Peffect on contractions induced by any of the ET analogues used. The NEP inhibitor CGS24592 (10 microM) inhibited contractions induced by ET-1(1-31) (6.2-fold rightward shift; Pbig ET-1. These data suggest that big ET-1 is processed predominantly by a CGS35066-sensitive ECE within allergic airways rather than by mast cell-derived proteases such as chymase. If endogenous ET-1(1-31) is formed within allergic airways, it is likely to undergo further conversion by NEP to more active products.

Study of Endothelin-1 and Vascular Endothelial Growth Factor in Patients with Cancer Colon

International Nuclear Information System (INIS)

ABDEL-GAWAD, I.A.; HASSANEIN, H.M.R.; BAHGAT, N.A.; ABDEL SATTAR, M.A.; EL-SISSY, A.H.; ALTAWEEL, M.A.; HELAL, A.M.

2008-01-01

Purpose: The levels of endothelin-1 and VEGF were evaluated in the sera of newly diagnosed patients with cancer colon and were compared with the routinely used tumor markers; CEA and CA19.9. Their relations with some prognostic factors of cancer colon were also investigated. Subjects and Methods: The study included 48 patients with cancer colon and 20 apparently healthy volunteers as a control group. Patients were 23 males and 25 females with age range from 18 to 71 years (mean = 47±1.8). Both serum and plasma samples were obtained from patients and controls. Results: Six percent of patients had grade 1 tumors, 77% had grade 2 and 17% had grade 3 disease. As regard to the stage, 52% of patients were stage II, 35.5% were stage III, while 12.5% were stage IV. Liver metastasis was present in 12.5%, while 35% showed lymph node metastasis. The VEGF, endothelin-1, CA 19.9 and CEA were significantly higher in the cancer colon patients than in control groups (p-value <0.001, 0.006, <0.001 and <0.001; respectively). Plasma level of endothelin-1 and serum level of VEGF showed significantly higher levels in advanced stages of the disease (p value <0 .001) and in presence of liver metastasis (p value <0.001 and 0.002 respectively), while VEGF showed significant result when compared with the grade (p value=0.032). In this study, when comparing the levels of plasma endothelin-1 and serum VEGF between the metastatic, non-metastatic liver patients of the cancer colon group and the control group, the comparison was statistically significant for both markers (p<0.001). Endothelin-1 and VEGF showed significant positive correlation (r=0.77 and p-value <0.0001). Serum VEGF and CA 19.9 showed good sensitivities which were not different (97.9% and 87.5%; respectively), while there was no significant difference between VEGF, CA 19.9 and CEA with respect to specificities (100%, 90% and 100% respectively). Conclusion: Both endothelin-1 and VEGF may be used for early detection of liver

Air pollution alters brain and pituitary endothelin-1 and inducible nitric oxide synthase gene expression.

Science.gov (United States)

Thomson, Errol M; Kumarathasan, Prem; Calderón-Garcidueñas, Lilian; Vincent, Renaud

2007-10-01

Recent work suggests that air pollution is a risk factor for cerebrovascular and neurodegenerative disease. Effects of inhaled pollutants on the production of vasoactive factors such as endothelin (ET) and nitric oxide (NO) in the brain may be relevant to disease pathogenesis. Inhaled pollutants increase circulating levels of ET-1 and ET-3, and the pituitary is a potential source of plasma ET, but the effects of pollutants on the expression of ET and NO synthase genes in the brain and pituitary are not known. In the present study, Fischer-344 rats were exposed by nose-only inhalation to particles (0, 5, 50mg/m3 EHC-93), ozone (0, 0.4, 0.8 ppm), or combinations of particles and ozone for 4 h. Real-time reverse transcription polymerase chain reaction was used to measure mRNA levels in the cerebral hemisphere and pituitary 0 and 24 h post-exposure. Ozone inhalation significantly increased preproET-1 but decreased preproET-3 mRNAs in the cerebral hemisphere, while increasing mRNA levels of preproET-1, preproET-3, and the ET-converting enzyme (ECE)-1 in the pituitary. Inducible NO synthase (iNOS) was initially decreased in the cerebral hemisphere after ozone inhalation, but increased 24 h post-exposure. Particles decreased tumour necrosis factor (TNF)-alpha mRNA in the cerebral hemisphere, and both particles and ozone decreased TNF-alpha mRNA in the pituitary. Our results show that ozone and particulate matter rapidly modulate the expression of genes involved in key vasoregulatory pathways in the brain and pituitary, substantiating the notion that inhaled pollutants induce cerebrovascular effects.

Targeting the ROS-HIF-1-endothelin axis as a therapeutic approach for the treatment of obstructive sleep apnea-related cardiovascular complications.

Science.gov (United States)

Belaidi, Elise; Morand, Jessica; Gras, Emmanuelle; Pépin, Jean-Louis; Godin-Ribuot, Diane

2016-12-01

Obstructive sleep apnea (OSA) is now recognized as an independent and important risk factor for cardiovascular diseases such as hypertension, coronary heart disease, heart failure and stroke. Clinical and experimental data have confirmed that intermittent hypoxia is a major contributor to these deleterious consequences. The repetitive occurrence of hypoxia-reoxygenation sequences generates significant amounts of free radicals, particularly in moderate to severe OSA patients. Moreover, in addition to hypoxia, reactive oxygen species (ROS) are potential inducers of the hypoxia inducible transcription factor-1 (HIF-1) that promotes the transcription of numerous adaptive genes some of which being deleterious for the cardiovascular system, such as the endothelin-1 gene. This review will focus on the involvement of the ROS-HIF-1-endothelin signaling pathway in OSA and intermittent hypoxia and discuss current and potential therapeutic approaches targeting this pathway to treat or prevent cardiovascular disease in moderate to severe OSA patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Interlimb Dynamic after Unilateral Focal Lesion of the Cervical Dorsal Corticospinal Tract with Endothelin-1

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Walther A. Carvalho

2017-10-01

Full Text Available Handedness is one of the most recognized lateralized behavior in humans. Usually, it is associated with manual superiority regarding performance proficiency. For instance, more than 90% of the human population is considered more skilled with the right hand, which is controlled by the left hemisphere, than with the left. However, during the performance of bimanual tasks, the two hands usually assume asymmetric roles, with one hand acting on objects while the other provides support, stabilizing the object. Traditionally, the role of the two hands is viewed as fixed. However, several studies support an alternate view with flexible assignments for the two hands depending on the task. The supporting role of the hand depends on a closed loop pathway based on proprioceptive inputs from the periphery. The circuit’s efferent arm courses through the dorsal corticospinal tract (dCST in rodents and terminate on spinal cord interneurons which modulate the excitability of motoneurons in the ventral horn. In the present work, we developed an experimental model of unilateral lesion targeting the cervical dCST with microinjections of the vasoconstrictor endothelin-1 (ET-1 to evaluate the degree of flexibility of forelimb assignment during a food manipulation task. Our results show that just 3 days after unilateral corticospinal tract (CST injury in the cervical region, rats display severe motor impairment of the ipsilateral forepaw together with a remarkable reversal of motor assignment between the forelimbs.

Evolution of endothelin receptors in vertebrates.

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Braasch, Ingo; Schartl, Manfred

2014-12-01

Endothelin receptors are G protein coupled receptors (GPCRs) of the β-group of rhodopsin receptors that bind to endothelin ligands, which are 21 amino acid long peptides derived from longer prepro-endothelin precursors. The most basal Ednr-like GPCR is found outside vertebrates in the cephalochordate amphioxus, but endothelin ligands are only present among vertebrates, including the lineages of jawless vertebrates (lampreys and hagfishes), cartilaginous vertebrates (sharks, rays, and chimaeras), and bony vertebrates (ray-finned fishes and lobe-finned vertebrates including tetrapods). A bona fide endothelin system is thus a vertebrate-specific innovation with important roles for regulating the cardiovascular system, renal and pulmonary processes, as well as for the development of the vertebrate-specific neural crest cell population and its derivatives. Expectedly, dysregulation of endothelin receptors and the endothelin system leads to a multitude of human diseases. Despite the importance of different types of endothelin receptors for vertebrate development and physiology, current knowledge on endothelin ligand-receptor interactions, on the expression of endothelin receptors and their ligands, and on the functional roles of the endothelin system for embryonic development and in adult vertebrates is very much biased towards amniote vertebrates. Recent analyses from a variety of vertebrate lineages, however, have shown that the endothelin system in lineages such as teleost fish and lampreys is more diverse and is divergent from the mammalian endothelin system. This diversity is mainly based on differential evolution of numerous endothelin system components among vertebrate lineages generated by two rounds of whole genome duplication (three in teleosts) during vertebrate evolution. Here we review current understanding of the evolutionary history of the endothelin receptor family in vertebrates supplemented with surveys on the endothelin receptor gene complement of

Regulatory mechanism of endothelin receptor B in the cerebral arteries after focal cerebral ischemia

DEFF Research Database (Denmark)

Grell, Anne-Sofie; Thigarajah, Rushani; Edvinsson, Lars

2014-01-01

BACKGROUND AND PURPOSE: Increased expression of endothelin receptor type B (ETBR), a vasoactive receptor, has recently been implied in the reduced cerebral blood flow and exacerbated neuronal damage after ischemia-reperfusion (I/R). The study explores the regulatory mechanisms of ETBR to identify...... drug targets to restore normal cerebral artery contractile function as part of successful neuroprotective therapy. METHODS: We have employed in vitro methods on human and rat cerebral arteries to study the regulatory mechanisms and the efficacy of target selective inhibitor, Mithramycin A (Mit...... the ETBR mRNA and protein levels. It also significantly reduced the ETBR mediated cerebrovascular contractility. Detailed analysis indicated that ERK1/2 mediated phosphorylation of Sp1 might be essential for ETBR transcription. CONCLUSION: Transcription factor Sp1 regulates the ETBR mediated...

Endothelin B Receptors on Primary Chicken Müller Cells and the Human MIO-M1 Müller Cell Line Activate ERK Signaling via Transactivation of Epidermal Growth Factor Receptors.

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Mohammad Harun-Or-Rashid

Full Text Available Injury to the eye or retina triggers Müller cells, the major glia cell of the retina, to dedifferentiate and proliferate. In some species they attain retinal progenitor properties and have the capacity to generate new neurons. The epidermal growth factor receptor (EGFR system and extracellular signal-regulated kinase (ERK signaling are key regulators of these processes in Müller cells. The extracellular signals that modulate and control these processes are not fully understood. In this work we studied whether endothelin receptor signaling can activate EGFR and ERK signaling in Müller cells. Endothelin expression is robustly upregulated at retinal injury and endothelin receptors have been shown to transactivate EGFRs in other cell types. We analyzed the endothelin signaling system in chicken retina and cultured primary chicken Müller cells as well as the human Müller cell line MIO-M1. The Müller cells were stimulated with receptor agonists and treated with specific blockers to key enzymes in the signaling pathway or with siRNAs. We focused on endothelin receptor mediated transactivation of EGFRs by using western blot analysis, quantitative reverse transcriptase PCR and immunocytochemistry. The results showed that chicken Müller cells and the human Müller cell line MIO-M1 express endothelin receptor B. Stimulation by the endothelin receptor B agonist IRL1620 triggered phosphorylation of ERK1/2 and autophosphorylation of (Y1173 EGFR. The effects could be blocked by Src-kinase inhibitors (PP1, PP2, EGFR-inhibitor (AG1478, EGFR-siRNA and by inhibitors to extracellular matrix metalloproteinases (GM6001, consistent with a Src-kinase mediated endothelin receptor response that engage ligand-dependent and ligand-independent EGFR activation. Our data suggest a mechanism for how injury-induced endothelins, produced in the retina, may modulate the Müller cell responses by Src-mediated transactivation of EGFRs. The data give support to a view in

Alternatively Activated (M2) Macrophage Phenotype Is Inducible by Endothelin-1 in Cultured Human Macrophages.

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Soldano, Stefano; Pizzorni, Carmen; Paolino, Sabrina; Trombetta, Amelia Chiara; Montagna, Paola; Brizzolara, Renata; Ruaro, Barbara; Sulli, Alberto; Cutolo, Maurizio

2016-01-01

Alternatively activated (M2) macrophages are phenotypically characterized by the expression of specific markers, mainly macrophage scavenger receptors (CD204 and CD163) and mannose receptor-1 (CD206), and participate in the fibrotic process by over-producing pro-fibrotic molecules, such as transforming growth factor-beta1 (TGFbeta1) and metalloproteinase (MMP)-9. Endothelin-1 (ET-1) is implicated in the fibrotic process, exerting its pro-fibrotic effects through the interaction with its receptors (ETA and ETB). The study investigated the possible role of ET-1 in inducing the transition from cultured human macrophages into M2 cells. Cultured human monocytes (THP-1 cell line) were activated into macrophages (M0 macrophages) with phorbol myristate acetate and subsequently maintained in growth medium (M0-controls) or treated with either ET-1 (100nM) or interleukin-4 (IL-4, 10ng/mL, M2 inducer) for 72 hours. Similarly, primary cultures of human peripheral blood monocyte (PBM)-derived macrophages obtained from healthy subjects, were maintained in growth medium (untreated cells) or treated with ET-1 or IL-4 for 6 days. Both M0 and PBM-derived macrophages were pre-treated with ET receptor antagonist (ETA/BRA, bosentan 10-5M) for 1 hour before ET-1 stimulation. Protein and gene expression of CD204, CD206, CD163, TGFbeta1 were analysed by immunocytochemistry, Western blotting and quantitative real time polymerase chain reaction (qRT-PCR). Gene expression of interleukin(IL)-10 and macrophage derived chemokine (CCL-22) was evaluated by qRT-PCR. MMP-9 production was investigated by gel zymography. ET-1 significantly increased the expression of M2 phenotype markers CD204, CD206, CD163, IL-10 and CCL-22, and the production of MMP-9 in both cultures of M0 and PBM-derived macrophages compared to M0-controls and untreated cells. In cultured PBM-derived macrophages, ET-1 increased TGFbeta1 protein and gene expression compared to untreated cells. The ET-1-mediated effects were

Endothelin-1 stimulates the release of preloaded [3H]D-aspartate from cultured cerebellar granule cells

International Nuclear Information System (INIS)

Lin, W.W.; Lee, C.Y.; Chuang, D.M.

1990-01-01

We have recently reported that endothelin-1 (ET) induces phosphoinositide hydrolysis in primary cultures of rat cerebellar granule cells. Here we found that ET in a dose-dependent manner (1-30 nM) stimulated the release of preloaded [ 3 H]D-aspartate from granule cells. The ET-induced aspartate release was completely blocked in the absence of extracellular Ca 2+ , but was unaffected by 1 mM Co 2+ or 1 microM dihydropyridine derivatives (nisoldipine and nimodipine). At higher concentration (10 microM) of nisoldipine and nimodipine, the release was partially inhibited. Short-term pretreatment of cells with phorbol 12,13-dibutyrate (PDBu) potentiated the ET-induced aspartate release, while long-term pretreatment with PDBu attenuated the release. Long-term exposure of cells to pertussis toxin (PTX), on the other hand, potentiated the ET-induced effects. Our results suggest that ET has a neuromodulatory function in the central nervous system

The effects of endothelin-1 on the cardiorespiratory physiology of the freshwater trout (Oncorhynchus mykiss) and the marine dogfish (Squalus acanthias).

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Perry, S F; Montpetit, C J; McKendry, J; Desforges, P R; Gilmour, K M; Wood, C M; Olson, K R

2001-11-01

The aim of the present study was to evaluate the effects of endothelin-l-elicited cardiovascular events on respiratory gas transfer in the freshwater rainbow trout (Oncorhynchus mykiss) and the marine dogfish (Squalus acanthias). In both species, endothelin-1 (666 pmol kg(-1)) caused a rapid (within 4 min) reduction (ca. 30-50 mmHg) in arterial blood partial pressure of O2. The effects of endothelin-1 on arterial blood partial pressure of CO2 were not synchronised with the changes in O2 partial pressure and the responses were markedly different in trout and dogfish. In trout, arterial CO2 partial pressure was increased transiently by approximately 1.0 mmHg but the onset of the response was delayed and occurred 12 min after endothelin-1 injection. In contrast, CO2 partial pressure remained more-or-less constant in dogfish after injection of endothelin-1 and was increased only slightly (approximately 0.1 mmHg) after 60 min. Pre-treatment of trout with bovine carbonic anhydrase (5 mg ml(-1)) eliminated the increase in CO2 partial pressure that was normally observed after endothelin-1 injection. In both species, endothelin-1 injection caused a decrease in arterial blood pH that mirrored the changes in CO2 partial pressure. Endothelin-1 injection was associated with transient (trout) or persistent (dogfish) hyperventilation as indicated by pronounced increases in breathing frequency and amplitude. In trout, arterial blood pressure remained constant or was decreased slightly and was accompanied by a transient increase in systemic resistance, and a temporary reduction in cardiac output. The decrease in cardiac output was caused solely by a reduction in cardiac frequency; cardiac stroke volume was unaffected. In dogfish, arterial blood pressure was lowered by approximately 10 mmHg at 6-10 min after endothelin-1 injection but then was rapidly restored to pre-injection levels. The decrease in arterial blood pressure reflected an increase in branchial vascular resistance (as

25 Years of endothelin research

DEFF Research Database (Denmark)

Emoto, Noriaki; Vignon-Zellweger, Nicolas; Lopes, Rhéure Alves Moreira

2014-01-01

In the past three decades, endothelin and endothelin receptor antagonists have received great scientific and clinical interest, leading to the publication of more than 27,000 scientific articles since its discovery. The Thirteenth International Conference on Endothelin (ET-13) was held on Septemb...

Endothelin-1 receptor antagonists protect the kidney against the nephrotoxicity induced by cyclosporine-A in normotensive and hypertensive rats.

Science.gov (United States)

Caires, A; Fernandes, G S; Leme, A M; Castino, B; Pessoa, E A; Fernandes, S M; Fonseca, C D; Vattimo, M F; Schor, N; Borges, F T

2017-12-11

Cyclosporin-A (CsA) is an immunosuppressant associated with acute kidney injury and chronic kidney disease. Nephrotoxicity associated with CsA involves the increase in afferent and efferent arteriole resistance, decreased renal blood flow (RBF) and glomerular filtration. The aim of this study was to evaluate the effect of Endothelin-1 (ET-1) receptor blockade with bosentan (BOS) and macitentan (MAC) antagonists on altered renal function induced by CsA in normotensive and hypertensive animals. Wistar and genetically hypertensive rats (SHR) were separated into control group, CsA group that received intraperitoneal injections of CsA (40 mg/kg) for 15 days, CsA+BOS and CsA+MAC that received CsA and BOS (5 mg/kg) or MAC (25 mg/kg) by gavage for 15 days. Plasma creatinine and urea, mean arterial pressure (MAP), RBF and renal vascular resistance (RVR), and immunohistochemistry for ET-1 in the kidney cortex were measured. CsA decreased renal function, as shown by increased creatinine and urea. There was a decrease in RBF and an increase in MAP and RVR in normotensive and hypertensive animals. These effects were partially reversed by ET-1 antagonists, especially in SHR where increased ET-1 production was observed in the kidney. Most MAC effects were similar to BOS, but BOS seemed to be better at reversing cyclosporine-induced changes in renal function in hypertensive animals. The results of this work suggested the direct participation of ET-1 in renal hemodynamics changes induced by cyclosporin in normotensive and hypertensive rats. The antagonists of ET-1 MAC and BOS reversed part of these effects.

Endothelin-1 receptor antagonists protect the kidney against the nephrotoxicity induced by cyclosporine-A in normotensive and hypertensive rats

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A. Caires

2017-12-01

Full Text Available Cyclosporin-A (CsA is an immunosuppressant associated with acute kidney injury and chronic kidney disease. Nephrotoxicity associated with CsA involves the increase in afferent and efferent arteriole resistance, decreased renal blood flow (RBF and glomerular filtration. The aim of this study was to evaluate the effect of Endothelin-1 (ET-1 receptor blockade with bosentan (BOS and macitentan (MAC antagonists on altered renal function induced by CsA in normotensive and hypertensive animals. Wistar and genetically hypertensive rats (SHR were separated into control group, CsA group that received intraperitoneal injections of CsA (40 mg/kg for 15 days, CsA+BOS and CsA+MAC that received CsA and BOS (5 mg/kg or MAC (25 mg/kg by gavage for 15 days. Plasma creatinine and urea, mean arterial pressure (MAP, RBF and renal vascular resistance (RVR, and immunohistochemistry for ET-1 in the kidney cortex were measured. CsA decreased renal function, as shown by increased creatinine and urea. There was a decrease in RBF and an increase in MAP and RVR in normotensive and hypertensive animals. These effects were partially reversed by ET-1 antagonists, especially in SHR where increased ET-1 production was observed in the kidney. Most MAC effects were similar to BOS, but BOS seemed to be better at reversing cyclosporine-induced changes in renal function in hypertensive animals. The results of this work suggested the direct participation of ET-1 in renal hemodynamics changes induced by cyclosporin in normotensive and hypertensive rats. The antagonists of ET-1 MAC and BOS reversed part of these effects.

Plasma Interleukin-8 and Endothelin-1 in Symptomatic and Asymptomatic Children

International Nuclear Information System (INIS)

Radwan, Z.; El-Abiad, N.; Soliman, M. S.; Ali, A.I.; Ali, G.S.

2004-01-01

This study was designed to evaluate the extent to which IL-8 and endothelin-1 are involved in the development of acute exacerbation of atopic asthma. Two asthmatic groups, each of 20 patients were studied, the asymptomatic group where patients were free of symptoms and the symptomatic group where patients were suffering from acute exacerbation of their asthma. Both of asthmatic groups were subclassified into mild and moderate subgroups, each of 10 patients according to the asthma severity. All subjects were subjected to chest X-ray and peak expiratory flow rate (PEFR) recording for sub-classification of patients, skin prick testing using common allergens (patients only) for the identification of atopic asthmatic patients and laboratory investigations including complete blood count (CBC), absolute eosi-nophil count (AEC), urine and stool exam-ination, total serum 1 gE level, plasma inter-leukin-8 (IL-8) level and plasma endothelin-1 (ET-1) level. The data obtained revealed non-significant differences between the studied groups as regards AEC, while serum total 1 gE of the asthmatic groups showed highly significant elevations in comparison to control group. Also, There were highly significant elevations in plasma endothelin-1 and plasma IL-8 levels of the symptomatic asthmatic subgroups in comparison to control group and asymptomatic asthmatic subgroups in comparison to control group and asymptomatic asthmatic subgroups. In conclusion: although it is clear now that IL-8 and ET-1 are involved in acute exacerbation of atopic asthmatic patients, a causal link between those mediators and development of the exacerbation has not been definitively established. Surely, those mediators, their receptors, synthesis and degradation pathways offer potentially important therapeutic targets

Nonhuman primate models of focal cerebral ischemia

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Jingjing Fan

2017-01-01

Full Text Available Rodents have been widely used in the production of cerebral ischemia models. However, successful therapies have been proven on experimental rodent stroke model, and they have often failed to be effective when tested clinically. Therefore, nonhuman primates were recommended as the ideal alternatives, owing to their similarities with the human cerebrovascular system, brain metabolism, grey to white matter ratio and even their rich behavioral repertoire. The present review is a thorough summary of ten methods that establish nonhuman primate models of focal cerebral ischemia; electrocoagulation, endothelin-1-induced occlusion, microvascular clip occlusion, autologous blood clot embolization, balloon inflation, microcatheter embolization, coil embolization, surgical suture embolization, suture, and photochemical induction methods. This review addresses the advantages and disadvantages of each method, as well as precautions for each model, compared nonhuman primates with rodents, different species of nonhuman primates and different modeling methods. Finally it discusses various factors that need to be considered when modelling and the method of evaluation after modelling. These are critical for understanding their respective strengths and weaknesses and underlie the selection of the optimum model.

Subarachnoid hemorrhage enhances endothelin receptor expression and function in rat cerebral arteries

DEFF Research Database (Denmark)

Hansen-Schwartz, Jacob; Hoel, Natalie Løvland; Zhou, Mingfang

2003-01-01

OBJECTIVE: Inspired by organ culture-induced changes in the vascular endothelin (ET) receptor population, we investigated whether such changes occur in cerebral arteries in a rat subarachnoid hemorrhage (SAH) model. METHODS: SAH was induced with injection of 250 microl of blood into the prechiasm......OBJECTIVE: Inspired by organ culture-induced changes in the vascular endothelin (ET) receptor population, we investigated whether such changes occur in cerebral arteries in a rat subarachnoid hemorrhage (SAH) model. METHODS: SAH was induced with injection of 250 microl of blood...... into the prechiasmatic cistern. After 2 days, the middle cerebral artery, basilar artery, and posterior communicating artery were harvested. Pharmacological studies were performed in vitro, and levels of messenger ribonucleic acid (mRNA) were quantified in real-time reverse transcriptase-polymerase chain reaction assays....... RESULTS: In the middle cerebral artery and basilar artery from rats with induced SAH, enhanced biphasic responses to ET-1 were observed. The -log(50% effective concentration) value for the high-affinity phase was approximately 12, compared with approximately 8.5 for sham-operated animals...

Plasma endothelin-1 and tumor necrosis factor-alpha concentrations in pregnant and cyclic rats after low-dose endotoxin infusion

NARCIS (Netherlands)

Faas, MM; Bakker, WW; Valkhof, N; Baller, JFW; Schuiling, GA

Plasma endothelin-1 and tumor necrosis factor-alpha were determined in pregnant and cyclic rats after infusion of either endotoxin (1.0 mu g/kg of body weight) or saline solution. After endotoxin, but not after saline solution, administration there was a transient endothelin-1 response in pregnant

Plasma Endothelin-1 Levels in Preterm Neonatal Infants with Acute Respiratory Failure

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D. V. Dmitriyev

2008-01-01

Full Text Available Increased pulmonary vascular resistance in preterm infants is associated with acute respiratory failure (ARF and at the same time endothelin-1 (E-1 plays an important role in neonatal pulmonary vascular responsiveness. Methods. Endothelin-1 levels were measured in two blood samples in 12 preterm infants with ARF and in 12 controls (at 32.2±1.3 and 29.8±1.2 weeks of gestation, respectively by enzyme immunoassay. For this, the first and second blood samples were taken at 18 to 40 hours after birth. Results. The plasma level of E-1 in the first sample did not differ between the neonates of both groups. In the second sample, significantly higher E-1 concentrations were observed in the newborns with ARF than in the controls. In the first sample, E-1 concentration were higher than in the second one in both groups (p<0.001. There was a significant positive correlation between the second E-1 sample and the SNAPPE 2 scale rating (r=0.38; p=0.02. The plasma level of E-1 in the first sample did not differ in both groups (11.9 and 12.2 pg/ml, respectively. Conclusion. Neonates with and without ARF had the similar plasma E-1 levels in the first sample, by taking into account the fact that the E-1 levels were higher in ARF than in the controls at 18 to 40 hour after birth. Increased vascular resistance in ARF may be associated with the high level of E-1. Key words: endothe-lin-1, acute respiratory failure.

The vascular endothelial growth factor receptor inhibitor sunitinib causes a preeclampsia-like syndrome with activation of the endothelin system

DEFF Research Database (Denmark)

Kappers, Mariëtte H W; Smedts, Frank M M; Horn, Thomas

2011-01-01

of endothelin 1, decreased nitric oxide (NO) bioavailability, and increased oxidative stress in the development of sunitinib-induced hypertension and renal toxicity. In rats on sunitinib, light and electron microscopic examination revealed marked glomerular endotheliosis, a characteristic histological feature...... be prevented with the endothelin receptor antagonist macitentan (¿BP: 12.3±1.5 mm Hg) and only mildly with Tempol, a superoxide dismutase mimetic (¿BP: 25.9±2.3 mm Hg). Both compounds could not prevent the sunitinib-induced rise in serum creatinine or renal histological abnormalities and had no effect on urine...

The vascular endothelial growth factor receptor inhibitor sunitinib causes a preeclampsia-like syndrome with activation of the endothelin system

DEFF Research Database (Denmark)

Kappers, Mariëtte H W; Smedts, Frank M M; Horn, Thomas

2011-01-01

of endothelin 1, decreased nitric oxide (NO) bioavailability, and increased oxidative stress in the development of sunitinib-induced hypertension and renal toxicity. In rats on sunitinib, light and electron microscopic examination revealed marked glomerular endotheliosis, a characteristic histological feature...... be prevented with the endothelin receptor antagonist macitentan (ΔBP: 12.3±1.5 mm Hg) and only mildly with Tempol, a superoxide dismutase mimetic (ΔBP: 25.9±2.3 mm Hg). Both compounds could not prevent the sunitinib-induced rise in serum creatinine or renal histological abnormalities and had no effect on urine...

Endothelin-1 is a Risk Factor for Pathogenesis of Hypertension

International Nuclear Information System (INIS)

Abdelhalim, Mohamed Anwar K.

2007-01-01

The purpose of this present study was to investigate the effects of endothelin-1 (ET-1) on the systemic blood pressure, microvascular blood flow velocity and diameter of arterioles and venules of the rat mesentery in vivo. For this purpose, the mesentery was arranged for in situ intravital microscopic observation under transillumination, and cumulative injections of ET-1(30-2000 p mole/kg) were infused intravenously through a catheter inserted into the right jugular vein. Infusion of low doses of ET-1(30-125 pmole/kg) induced a slight increase in the systemic blood pressure, a dose-dependent increase in blood flow velocity of arterioles (20-30 micron m) and venules (30-50 micron m). Diameters of arterioles and venules exhibited no significant change as compared with the control data. On the contrary, the infusion of high doses of ET-1 (250-2000 pmole/kg) induced a long-lasting pressor effect, a dose-dependent decrease in the blood flow velocity of arterioles and venules. Microvascular diameter exhibited a vasoconstrictive effect more prominent in arterioles than in venules. These findings suggest that vasoconstriction produced by ET-1 in rat mesenteric microcirculation may be the causal factor for its potent pressor effect in rats. Moreover, ET-1 may be involved in the regulation of the blood flow velocity distribution of rat mesenteric microcirculation. Finally, ET-1 may be considered as one of the more important risk factors which contribute to the pathogenesis of hypertension. (author)

Impact of endothelin blockade on acute exercise-induced changes in blood flow and endothelial function in type 2 diabetes mellitus.

NARCIS (Netherlands)

Schreuder, T.H.A.; Lotringen, J.H. van; Hopman, M.T.E.; Thijssen, D.H.J.

2014-01-01

Positive vascular effects of exercise training are mediated by acute increases in blood flow. Type 2 diabetes patients show attenuated exercise-induced increases in blood flow, possibly mediated by the endothelin pathway, preventing an optimal stimulus for vascular adaptation. We examined the impact

Endothelin-1 stimulates the release of preloaded ( sup 3 H)D-aspartate from cultured cerebellar granule cells

Energy Technology Data Exchange (ETDEWEB)

Lin, W.W.; Lee, C.Y.; Chuang, D.M. (NIMH Neuroscience Center, Washington, DC (USA))

1990-03-16

We have recently reported that endothelin-1 (ET) induces phosphoinositide hydrolysis in primary cultures of rat cerebellar granule cells. Here we found that ET in a dose-dependent manner (1-30 nM) stimulated the release of preloaded ({sup 3}H)D-aspartate from granule cells. The ET-induced aspartate release was completely blocked in the absence of extracellular Ca{sup 2+}, but was unaffected by 1 mM Co{sup 2+} or 1 microM dihydropyridine derivatives (nisoldipine and nimodipine). At higher concentration (10 microM) of nisoldipine and nimodipine, the release was partially inhibited. Short-term pretreatment of cells with phorbol 12,13-dibutyrate (PDBu) potentiated the ET-induced aspartate release, while long-term pretreatment with PDBu attenuated the release. Long-term exposure of cells to pertussis toxin (PTX), on the other hand, potentiated the ET-induced effects. Our results suggest that ET has a neuromodulatory function in the central nervous system.

Role of ERK/MAPK in endothelin receptor signaling in human aortic smooth muscle cells

DEFF Research Database (Denmark)

Chen, Qing-wen; Edvinsson, Lars; Xu, Cang-Bao

2009-01-01

muscle cells (VSMCs) through activation of endothelin type A (ETA) and type B (ETB) receptors. The extracellular signal-regulated kinase 1 and 2 (ERK1/2) mitogen-activated protein kinases (MAPK) are involved in ET-1-induced VSMC contraction and proliferation. This study was designed to investigat...

Endothelin receptors and activity differ in human, dog, and rabbit lung.

Science.gov (United States)

McKay, K O; Armour, C L; Black, J L

1996-01-01

In this study, we have examined dog and rabbit airways as potential models for human airways in regard to the activity of endothelin. The receptors involved in the response to endothelin-1 (ET-1) in airway tissue from human, rabbit, and dog lung were investigated, as was the mechanism responsible for the contraction to ET-1 in tissue from the three species. By using specific endothelin receptor agonists and antagonists, we have demonstrated that ETB receptors predominate in rabbit and human airways and ETA receptors in dog airways. The contraction to ET-1 is not dependent on cyclooxygenase products of arachidonic acid, as indomethacin had no effect on the response to ET-1. Extracellular calcium influx via voltage-dependent channels is necessary for contraction to ET-1 in rabbit and dog airways. These results are in contrast to our previously reported results in human airways, in which neither removal of extracellular calcium nor verapamil affected the ET-1 response. The sustained phase of the contraction to ET-1 in all three species may be mediated in part by activation of protein kinase C (PKC), as the inhibitor staurosporine significantly altered the time course of the response to endothelin. We therefore conclude that in rabbit airways ET-1 activates ETB receptors, triggers the influx of extracellular calcium through voltage-dependent channels, and induces a contractile response that is, in part, dependent upon stimulation of PKC. The same mechanism is triggered in dog bronchus; however, the receptors involved in this species are of the ETA type. Finally, in human airways, the contractile response to ET-1, while independent of extracellular calcium influx, is dependent upon PKC activation after binding of the peptide to ETB receptors.

Endothelin-1 and -3 plasma concentrations in patients with cirrhosis: role of splanchnic and renal passage and liver function

DEFF Research Database (Denmark)

Gerbes, A L; Møller, S; Gülberg, V

1995-01-01

of splanchnic and renal passage and of liver function on plasma concentrations of endothelin-1 (ET-1) and endothelin-3 (ET-3) in patients with cirrhosis compared with controls. Eighteen patients with cirrhosis and 8 normotensive controls of similar age were investigated. Arterial and venous plasma samples were...

Cooperation of endothelin-1 signaling with melanosomes plays a role in developing and/or maintaining human skin hyperpigmentation

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Daiki Murase

2015-10-01

Full Text Available Skin hyperpigmentation is characterized by increased melanin synthesis and deposition that can cause significant psychosocial and psychological distress. Although several cytokine-receptor signaling cascades contribute to the formation of ultraviolet B-induced cutaneous hyperpigmentation, their possible involvement in other types of skin hyperpigmentation has never been clearly addressed. Since our continuous studies using skin specimens from more than 30 subjects with ethnic skin diversity emphasized a consistent augmentation in the expression of endothelin-1 (ET-1 and its receptor (Endothelin B receptor, ET-B in hyperpigmented lesions, including senile lentigos (SLs, the precise function of ET-1 signaling was investigated in the present study. In line with previous studies, ET-1 significantly induced melanogenesis followed by increases in melanosome transport in melanocytes and in its transfer to keratinocytes while inhibition of ET-B function substantially depressed melanogenic ability in tissue-cultured SLs. Additionally, in agreement with a previous report that the formation of autophagosomes rather than melanosomes is stimulated according to starvation or defective melanosome production, ET-1 was found to remarkably augment the expression of components necessary for early melanosome formation, indicating its counteraction against autophagy-targeting melanosome degradation in melanocytes. Despite the lack of substantial impact of ET-1 on keratinocyte melanogenic functions, the expression of ET-1 was enhanced following melanosome uptake by keratinocytes. Taken together, our data suggest that ET-1 plays a substantial role in the development and/or maintenance of skin hyperpigmentation in reciprocal cooperation with increased melanosome incorporation.

Genetic interactions between neurofibromin and endothelin receptor B in mice.

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Mugdha Deo

Full Text Available When mutations in two different genes produce the same mutant phenotype, it suggests that the encoded proteins either interact with each other, or act in parallel to fulfill a similar purpose. Haploinsufficiency of Neurofibromin and over-expression of Endothelin 3 both cause increased numbers of melanocytes to populate the dermis during mouse development, and thus we are interested in how these two signaling pathways might intersect. Neurofibromin is mutated in the human genetic disease, neurofibromatosis type 1, which is characterized by the development of Schwann cell based tumors and skin hyper-pigmentation. Neurofibromin is a GTPase activating protein, while the Endothelin 3 ligand activates Endothelin receptor B, a G protein coupled receptor. In order to study the genetic interactions between endothelin and neurofibromin, we defined the deletion breakpoints of the classical Ednrb piebald lethal allele (Ednrb(s-l and crossed these mice to mice with a loss-of-function mutation in neurofibromin, Dark skin 9 (Dsk9. We found that Neurofibromin haploinsufficiency requires Endothelin receptor B to darken the tail dermis. In contrast, Neurofibromin haploinsufficiency increases the area of the coat that is pigmented in Endothelin receptor B null mice. We also found an oncogenic mutation in the G protein alpha subunit, GNAQ, which couples to Endothelin receptor B, in a uveal melanoma from a patient with neurofibromatosis type 1. Thus, this data suggests that there is a complex relationship between Neurofibromin and Endothelin receptor B.

Insulin decreases atherosclerosis by inducing endothelin receptor B expression

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Park, Kyoungmin; Mima, Akira; Li, Qian

2016-01-01

Endothelial cell (EC) insulin resistance and dysfunction, caused by diabetes, accelerates atherosclerosis. It is unknown whether specifically enhancing EC-targeted insulin action can decrease atherosclerosis in diabetes. Accordingly, overexpressing insulin receptor substrate-1 (IRS1...... induction of NO action, which increases endothelin receptor B (EDNRB) expression and intracellular [Ca(2+)]. Using the mice with knockin mutation of eNOS, which had Ser1176 mutated to alanine (AKI), deleting the only known mechanism for insulin to activate eNOS/NO pathway, we observed that IRS1...... overexpression in the endothelia of Aki/ApoE(-/-) mice significantly decreased atherosclerosis. Interestingly, endothelial EDNRB expression was selectively reduced in intima of arteries from diabetic patients and rodents. However, endothelial EDNRB expression was upregulated by insulin via P13K/Akt pathway...

Low levels of plasma endothelin-1 in patients with retinitis pigmentosa

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Hiroshi Ohguro

2010-06-01

Full Text Available Hiroshi Ohguro1, Yukihiko Mashima2, Mitsuru Nakazawa31Department of Ophthalmology, Sapporo Medical University School of Medicine, 2Department of Ophthalmology, Keio University School of Medicine, 3Department of Ophthalmology, Hirosaki University School of Medicine, JapanPurpose: The aim of this study was to elucidate the role of endothelin-1 (ET-1 in the pathophysiology of retinitis pigmentosa (RP.Methods: Plasma ET-1 levels and ophthalmic features in 50 RP patients were compared with those in 20 healthy-eye control subjects. Plasma ET-1 concentrations were determined using a commercially available enzyme-linked immunosorbent assay kit.Results: Mean plasma ET-1 levels of RP patients (1.88 ± 0.56 pg/mL were significantly lower than those of control subjects (2.30 ± 0.30 pg/mL, Mann-Whitney’s U test; P < 0.01. However, ET-1 concentrations varied markedly in each patient. Among RP patients, a significant correlation of ET-1 concentrations was not observed in terms of its hereditary forms or other clinical factors.Conclusion: ET-1 may be important in the pathogenesis of RP, and measurement of its plasma concentrations may also contribute to additional insights into the retinal hemodynamics of RP.Keywords: endothelin-1, retinitis pigmentosa, retinal hemodynamics

Electroacupuncture pretreatment induces tolerance against focal cerebral ischemia through activation of canonical Notch pathway

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Zhao Yu

2012-09-01

Full Text Available Abstract Background Electroacupuncture (EA pretreatment can induce the tolerance against focal cerebral ischemia. However, the underlying mechanisms have not been fully understood. Emerging evidences suggest that canonical Notch signaling may be involved in ischemic brain injury. In the present study, we tested the hypothesis that EA pretreatment-induced tolerance against focal cerebral ischemia is mediated by Notch signaling. Results EA pretreatment significantly enhanced Notch1, Notch4 and Jag1 gene transcriptions in the striatum, except Notch1 intracellular domain level, which could be increased evidently by ischemia. After ischemia and reperfusion, Hes1 mRNA and Notch1 intracellular domain level in ischemic striatum in EA pretreatment group were increased and reached the peak at 2 h and 24 h, respectively, which were both earlier than the peak achieved in control group. Intraventricular injection with the γ-secretase inhibitor MW167 attenuated the neuroprotective effect of EA pretreatment. Conclusions EA pretreatment induces the tolerance against focal cerebral ischemia through activation of canonical Notch pathway.

Contractile effects and binding properties of endothelins/sarafotoxins in the guinea pig ileum.

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Wollberg, Z; Bdolah, A; Galron, R; Sokolovsky, M; Kochva, E

1991-05-30

Seven of the eight known isopeptides of the endothelin/sarafotoxin (ET/SRTX) family were tested on the isolated guinea pig ileum and found to cause a concentration-dependent increase in basal tone. The rate or the amplitude of the spontaneous rhythmic contractions of the ileal smooth muscle were essentially not affected by any of the peptides. The maximum contraction elicited by vasoactive intestinal contractor (VIC) was slightly stronger than that induced by endothelin-1 (ET-1) or sarafotoxin-b (SRTX-b), and significantly stronger than the maximal contractions elicited by sarafotoxin-a (SRTX-a), sarafotoxin-c (SRTX-c), or endothelin-3 (ET-3). Sarafotoxin-d (SRTX-d) caused, essentially, no contraction but a rather marked relaxation. The potencies of the various peptides to induce the increase in tension, in terms of EC50 values (cumulative effective concentrations that induce half-maximum response), ranged between 6 and 95 nM depending on the peptide. VIC, ET-1, SRTX-b and SRTX-a had similar potencies and were significantly more potent than SRTX-c and ET-3. A high concentration of SRTX-b elicited no additional response when applied to the organ bath after one of the other peptides had shown a maximal effect. Binding experiments with ileal membranes revealed similar binding properties for the various peptides. Competition with iodinated SRTX-b showed no meaningful differences between the various peptides. It is concluded that all the ET/SRTX peptides compete for the same receptor subtype in the ileum. In terms of efficacy, VIC can be considered as a full agonist of this receptor, SRTX-d is probably an antagonist, while all the other peptides behave as partial agonists.

CaMKII inhibition with KN93 attenuates endothelin and serotonin receptor-mediated vasoconstriction and prevents subarachnoid hemorrhage-induced deficits in sensorimotor function

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Edvinsson, Lars; Povlsen, Gro Klitgaard; Ahnstedt, Hilda

2014-01-01

tested the hypothesis that inhibition of calcium calmodulin-dependent protein kinase II (CaMKII) may reduce cerebral vasoconstriction mediated by endothelin and serotonin receptors and improve neurological outcome after experimental SAH. METHODS: SAH was induced in adult rats by injection of 250 μ...

Vascular endothelin ET(B) receptor-mediated contraction requires phosphorylation of ERK1/2 proteins

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Luo, Guogang; Jamali, Roya; Cao, Yong-Xiao

2006-01-01

In cardiovascular diseases, endothelin type B (ET(B)) receptors in arterial smooth muscle cells are upregulated. The present study revealed that organ culture of rat mesenteric artery segments enhanced endothelin ET(B) receptor-mediated contraction paralleled with increase in the receptor mRNA an...

Correlation between plasma endothelin-1 levels and severity of septic liver failure quantified by maximal liver function capacity (LiMAx test. A prospective study.

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Magnus F Kaffarnik

Full Text Available To investigate the relationship between the degree of liver dysfunction, quantified by maximal liver function capacity (LiMAx test and endothelin-1, TNF-α and IL-6 in septic surgical patients.28 septic patients (8 female, 20 male, age range 35-80y were prospectively investigated on a surgical intensive care unit. Liver function, defined by LiMAx test, and measurements of plasma levels of endothelin-1, TNF-α and IL-6 were carried out within the first 24 hours after onset of septic symptoms, followed by day 2, 5 and 10. Patients were divided into 2 groups (group A: LiMAx ≥100 μg/kg/h, moderate liver dysfunction; group B: LiMAx <100 μg/kg/h, severe liver dysfunction for analysis and investigated regarding the correlation between endothelin-1 and the severity of liver failure, quantified by LiMAx test.Group B showed significant higher results for endothelin-1 than patients in group A (P = 0.01, d5; 0.02, d10. For TNF-α, group B revealed higher results than group A, with a significant difference on day 10 (P = 0.005. IL-6 showed a non-significant trend to higher results in group B. The Spearman's rank correlation coefficient revealed a significant correlation between LiMAx and endothelin-1 (-0.434; P <0.001, TNF-α (-0.515; P <0.001 and IL-6 (-0.590; P <0.001.Sepsis-related hepatic dysfunction is associated with elevated plasma levels of endothelin-1, TNF-α and IL-6. Low LiMAx results combined with increased endothelin-1 and TNF-α and a favourable correlation between LiMAx and cytokine values support the findings of a crucial role of Endothelin-1 and TNF-α in development of septic liver failure.

Regular aerobic exercise reduces endothelin-1-mediated vasoconstrictor tone in overweight and obese adults.

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Dow, Caitlin A; Stauffer, Brian L; Brunjes, Danielle L; Greiner, Jared J; DeSouza, Christopher A

2017-09-01

What is the central question of this study? Does aerobic exercise training reduce endothelin-1 (ET-1)-mediated vasoconstrictor tone in overweight/obese adults? And, if so, does lower ET-1 vasoconstriction underlie the exercise-related enhancement in endothelium-dependent vasodilatation in overweight/obese adults? What is the main finding and its importance? Regular aerobic exercise reduces ET-1-mediated vasoconstrictor tone in previously sedentary overweight/obese adults, independent of weight loss. Decreased ET-1 vasoconstriction is an important mechanism underlying the aerobic exercise-induced improvement in endothelium-dependent vasodilator function in overweight/obese adults. Endothelin-1 (ET-1)-mediated vasoconstrictor tone is elevated in overweight and obese adults, contributing to vasomotor dysfunction and increased cardiovascular disease risk. Although the effects of habitual aerobic exercise on endothelium-dependent vasodilatation in overweight/obese adults have been studied, little is known regarding ET-1-mediated vasoconstriction. Accordingly, the aims of the present study were to determine the following: (i) whether regular aerobic exercise training reduces ET-1-mediated vasoconstrictor tone in overweight and obese adults; and, if so, (ii) whether the reduction in ET-1-mediated vasoconstriction contributes to exercise-induced improvement in endothelium-dependent vasodilatation in this population. Forearm blood flow (FBF) in response to intra-arterial infusion of selective ET A receptor blockade (BQ-123, 100 nmol min -1 for 60 min), acetylcholine [4.0, 8.0 and 16.0 μg (100 ml tissue) -1  min -1 ] in the absence and presence of ET A receptor blockade and sodium nitroprusside [1.0, 2.0 and 4.0 μg (100 ml tissue) -1  min -1 ] were determined before and after a 3 month aerobic exercise training intervention in 25 (16 men and nine women) overweight/obese (body mass index 30.1 ± 0.5 kg m -2 ) adults. The vasodilator response to BQ-123 was

Role of Dlx6 in regulation of an endothelin-1-dependent, dHAND branchial arch enhancer

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Charité, Jeroen; McFadden, David G.; Merlo, Giorgio; Levi, Giovanni; Clouthier, David E.; Yanagisawa, Masashi; Richardson, James A.; Olson, Eric N.

2001-01-01

Neural crest cells play a key role in craniofacial development. The endothelin family of secreted polypeptides regulates development of several neural crest sublineages, including the branchial arch neural crest. The basic helix–loop–helix transcription factor dHAND is also required for craniofacial development, and in endothelin-1 (ET-1) mutant embryos, dHAND expression in the branchial arches is down-regulated, implicating it as a transcriptional effector of ET-1 action. To determine the mechanism that links ET-1 signaling to dHAND transcription, we analyzed the dHAND gene for cis-regulatory elements that control transcription in the branchial arches. We describe an evolutionarily conserved dHAND enhancer that requires ET-1 signaling for activity. This enhancer contains four homeodomain binding sites that are required for branchial arch expression. By comparing protein binding to these sites in branchial arch extracts from endothelin receptor A (EdnrA) mutant and wild-type mouse embryos, we identified Dlx6, a member of the Distal-less family of homeodomain proteins, as an ET-1-dependent binding factor. Consistent with this conclusion, Dlx6 was down-regulated in branchial arches from EdnrA mutant mice. These results suggest that Dlx6 acts as an intermediary between ET-1 signaling and dHAND transcription during craniofacial morphogenesis. PMID:11711438

Endothelin-1 activation of ETB receptors leads to a reduced cellular proliferative rate and an increased cellular footprint

International Nuclear Information System (INIS)

Wilson, Jamie L.; Taylor, Linda; Polgar, Peter

2012-01-01

Endothelin-1 (ET-1) is a vasoactive peptide which signals through two G-protein coupled receptors, endothelin receptor A (ETA) and B (ETB). We determined that ET-1 activation of its ETB receptor in stably cDNA transfected CHO cells leads to a 55% reduction in cell number by end-point cell counting and a 35% decrease in cell growth by a real-time cell-substrate impedance-based assay after 24 h of cell growth. When CHO ETB cells were synchronized in the late G1 cell cycle phase, ET-1 delayed their S phase progression compared to control by 30% as determined by [ 3 H]-thymidine incorporation. On the other hand, no such delay was observed during late G2/M to G1 transit when cells were treated with ET-1 after release from mitotic arrest. Using the cell-substrate impedance-based assay, we observed that ET-1 induces opposing morphological changes in CHO ETA and CHO ETB cells with ETB causing an increase in the cell footprint and ETA a decrease. Likewise, in pulmonary artery smooth muscle cells, which express both ETA and ETB receptors, ET-1 induces an ETA-dependent contraction and an ETB dependent dilation. These results are shedding light on a possible beneficial role for ETB in diseases involving ET-1 dysfunction such as pulmonary hypertension. -- Highlights: ► ET- hinders cell proliferation in CHO cells transfected with ETB. ► ET-1 also decreases the rate of DNA synthesis in CHO ETB cells. ► JNK and PI3K appear to be involved in this reduction of DNA synthesis. ► ETB activation in CHO ETB cells and hSMCs leads to dilatory morphological changes. ► In CHO ETA and hSMCs, ETA activation leads to constrictive morphological changes.

Endothelin-1 activation of ETB receptors leads to a reduced cellular proliferative rate and an increased cellular footprint

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Wilson, Jamie L.; Taylor, Linda; Polgar, Peter, E-mail: peterp@bu.edu

2012-06-10

Endothelin-1 (ET-1) is a vasoactive peptide which signals through two G-protein coupled receptors, endothelin receptor A (ETA) and B (ETB). We determined that ET-1 activation of its ETB receptor in stably cDNA transfected CHO cells leads to a 55% reduction in cell number by end-point cell counting and a 35% decrease in cell growth by a real-time cell-substrate impedance-based assay after 24 h of cell growth. When CHO ETB cells were synchronized in the late G1 cell cycle phase, ET-1 delayed their S phase progression compared to control by 30% as determined by [{sup 3}H]-thymidine incorporation. On the other hand, no such delay was observed during late G2/M to G1 transit when cells were treated with ET-1 after release from mitotic arrest. Using the cell-substrate impedance-based assay, we observed that ET-1 induces opposing morphological changes in CHO ETA and CHO ETB cells with ETB causing an increase in the cell footprint and ETA a decrease. Likewise, in pulmonary artery smooth muscle cells, which express both ETA and ETB receptors, ET-1 induces an ETA-dependent contraction and an ETB dependent dilation. These results are shedding light on a possible beneficial role for ETB in diseases involving ET-1 dysfunction such as pulmonary hypertension. -- Highlights: Black-Right-Pointing-Pointer ET- hinders cell proliferation in CHO cells transfected with ETB. Black-Right-Pointing-Pointer ET-1 also decreases the rate of DNA synthesis in CHO ETB cells. Black-Right-Pointing-Pointer JNK and PI3K appear to be involved in this reduction of DNA synthesis. Black-Right-Pointing-Pointer ETB activation in CHO ETB cells and hSMCs leads to dilatory morphological changes. Black-Right-Pointing-Pointer In CHO ETA and hSMCs, ETA activation leads to constrictive morphological changes.

Binding sites for endothelin-1 in rat tissues: An autoradiographic study

International Nuclear Information System (INIS)

Koseki, C.; Imai, M.; Hirata, Y.; Yanagisawa, M.; Masaki, T.

1989-01-01

By tissue autoradiography in the rat, we demonstrated that receptors for endothelin-1 (ET-1) were distributed not only in the cardiovascular system but also in the noncardiovascular organs including the brain, lung, intestine, etc. In the brain, the receptors were mainly found in the basal ganglia and brainstem, in which nuclei are known to be cardiovascular regulatory sites. In addition to its direct vasoconstricting action, ET-1 may exert neural cardiovascular control as a neuropeptide

Facial hyperalgesia due to direct action of endothelin-1 in the trigeminal ganglion of mice.

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Gomes, Lenyta Oliveira; Chichorro, Juliana Geremias; Araya, Erika Ivanna; de Oliveira, Jade; Rae, Giles Alexander

2018-03-23

This study assessed the ability of endothelin-1 (ET-1) to evoke heat hyperalgesia when injected directly into the trigeminal ganglia (TG) of mice and determined the receptors implicated in this effect. The effects of TG ET A and ET B receptor blockade on alleviation of heat hyperalgesia in a model of trigeminal neuropathic pain induced by infraorbital nerve constriction (CION) were also examined. Naive mice received an intraganglionar (i.g.) injection of ET-1 (0.3-3 pmol) or the selective ET B R agonist sarafotoxin S6c (3-30 pmol), and response latencies to ipsilateral heat stimulation were assessed before the treatment and at 1-h intervals up to 5 h after the treatment. Heat hyperalgesia induced by i.g. ET-1 or CION was assessed after i.g. injections of ET A R and ET B R antagonists (BQ-123 and BQ-788, respectively, each at 0.5 nmol). Intraganglionar ET-1 or sarafotoxin S6c injection induced heat hyperalgesia lasting 4 and 2 h, respectively. Heat hyperalgesia induced by ET-1 was attenuated by i.g. BQ-123 or BQ-788. On day 5 after CION, i.g. BQ-788 injection produced a more robust antihyperalgesic effect compared with BQ-123. ET-1 injection into the TG promotes ET A R/ET B R-mediated facial heat hyperalgesia, and both receptors are clearly implicated in CION-induced hyperalgesia in the murine TG system. © 2018 Royal Pharmaceutical Society.

Plasma concentrations of endothelin in patients with abnormal vascular reactivity

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Predel, H.G.; Meyer-Lehnert, H.; Baecker, A.; Stelkens, H.; Kramer, H.J.

1990-01-01

We measured circulating concentrations of endothelin in healthy subjects and in patients with abnormal vascular reactivity. Endothelin concentrations were determined by radioimmunoassay after extraction of plasma using Sep-Pak C-18 cartridges in healthy subjects, in patients with diabetes mellitus type I, in patients with mild to moderate essential hypertension and in non-dialyzed patients with stable chronic renal failure. Plasma concentrations were similar in healthy controls, in diabetics and in hypertensive patients averaging 5.0±0.6 pg/ml, 4.7±0.2 pg/ml and 6.5±1.0 pg/ml, respectively. In contrast, plasma concentrations of endothelin were markedly elevated in patients with chronic renal failure averaging 16.6±2.9 pg/ml. No correlations were observed between serum creatinine concentrations ranging from 124 to 850 μmol/l or blood pressure and plasma concentrations of endothelin. Bicycle ergometric exercise in six healthy subjects and an acute modest i.v. saline load of 1,000 ml of 0.45% NaCl administered within 60 min in six patients with mild essential hypertension did not affect plasma concentrations of endothelin

Role of ERK/MAPK in endothelin receptor signaling in human aortic smooth muscle cells

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Chen, Qing-wen; Edvinsson, Lars; Xu, Cang-Bao

2009-01-01

muscle cells (VSMCs) through activation of endothelin type A (ETA) and type B (ETB) receptors. The extracellular signal-regulated kinase 1 and 2 (ERK1/2) mitogen-activated protein kinases (MAPK) are involved in ET-1-induced VSMC contraction and proliferation. This study was designed to investigate...... agonist, Sarafotoxin 6c (S6c) caused a time-dependent ERK1/2 activation with a maximal effect by less than 20% of the ET-1-induced activation of ERK1/2. Increase in bosentan concentration up to 10 microM further inhibited ET-1-induced activation of ERK1/2 and had a stronger inhibitory effect than BQ123...

Celecoxib offsets the negative renal influences of cyclosporine via modulation of the TGF-β1/IL-2/COX-2/endothelin ET(B) receptor cascade.

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El-Gowelli, Hanan M; Helmy, Maged W; Ali, Rabab M; El-Mas, Mahmoud M

2014-03-01

Endothelin (ET) signaling provokes nephrotoxicity induced by the immunosuppressant drug cyclosporine A (CSA). We tested the hypotheses that (i): celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, counterbalances renal derangements caused by CSA in rats and (ii) the COX-2/endothelin ET(B) receptor signaling mediates the CSA-celecoxib interaction. Ten-day treatment with CSA (20 mg/kg/day) significantly increased biochemical indices of renal function (serum urea, creatinine), inflammation (interleukin-2, IL-2) and fibrosis (transforming growth factor-β₁, TGF-β₁). Histologically, CSA caused renal tubular atrophy along with interstitial fibrosis. These detrimental renal effects of CSA were largely reduced in rats treated concurrently with celecoxib (10 mg/kg/day). We also report that cortical glomerular and medullary tubular protein expressions of COX-2 and ET(B) receptors were reduced by CSA and restored to near-control values in rats treated simultaneously with celecoxib. The importance of ET(B) receptors in renal control and in the CSA-celecoxib interaction was further verified by the findings (i) most of the adverse biochemical, inflammatory, and histopathological profiles of CSA were replicated in rats treated with the endothelin ETB receptor antagonist BQ788 (0.1 mg/kg/day, 10 days), and (ii) the BQ788 effects, like those of CSA, were alleviated in rats treated concurrently with celecoxib. Together, the data suggest that the facilitation of the interplay between the TGF-β1/IL-2/COX-2 pathway and the endothelin ET(B) receptors constitutes the cellular mechanism by which celecoxib ameliorates the nephrotoxic manifestations of CSA in rats. Copyright © 2014 Elsevier Inc. All rights reserved.

Andrographolide inhibits hypoxia-induced HIF-1α-driven endothelin 1 secretion by activating Nrf2/HO-1 and promoting the expression of prolyl hydroxylases 2/3 in human endothelial cells.

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Lin, Hung-Chih; Su, Shih-Li; Lu, Chia-Yang; Lin, Ai-Hsuan; Lin, Wan-Chun; Liu, Chin-San; Yang, Ya-Chen; Wang, Hsiu-Miao; Lii, Chong-Kuei; Chen, Haw-Wen

2017-03-01

Andrographolide, the main bioactive component of the medicinal plant Andrographis paniculata, has been shown to possess potent anti-inflammatory activity. Endothelin 1 (ET-1), a potent vasoconstrictor peptide produced by vascular endothelial cells, displays proinflammatory property. Hypoxia-inducible factor 1α (HIF-1α), the regulatory member of the transcription factor heterodimer HIF-1α/β, is one of the most important molecules that responds to hypoxia. Changes in cellular HIF-1α protein level are the result of altered gene transcription and protein stability, with the latter being dependent on prolyl hydroxylases (PHDs). In this study, inhibition of pro-inflammatory ET-1 expression and changes of HIF-1α gene transcription and protein stability under hypoxia by andrographolide in EA.hy926 endothelial-like cells were investigated. Hypoxic conditions were created using the hypoxia-mimetic agent CoCl 2. We found that hypoxia stimulated the production of reactive oxygen species (ROS), the expression of HIF-1α mRNA and protein, and the expression and secretion of ET-1. These effects, however, were attenuated by co-exposure to andrographolide, bilirubin, and RuCO. Silencing Nrf2 and heme oxygenase 1 (HO-1) reversed the inhibitory effects of andrographolide on hypxoia-induced HIF-1α mRNA and protein expression. Moreover, andrographolide increased the expression of prolyl hydroxylases (PHD) 2/3, which hydroxylate HIF-1α and promotes HIF-1α proteasome degradation, with an increase in HIF-1α hydroxylation was noted under hypoxia. Inhibition of p38 MAPK abrogated the hypoxia-induced increases in HIF-1α mRNA and protein expression as well as ET-1 mRNA expression and secretion. Taken together, these results suggest that andrographolide suppresses hypoxia-induced pro-inflammatory ET-1 expression by activating Nrf2/HO-1, inhibiting p38 MAPK signaling, and promoting PHD2/3 expression. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 918-930, 2017. © 2016 Wiley

Vascular endothelial cells mediate mechanical stimulation-induced enhancement of endothelin hyperalgesia via activation of P2X2/3 receptors on nociceptors.

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Joseph, Elizabeth K; Green, Paul G; Bogen, Oliver; Alvarez, Pedro; Levine, Jon D

2013-02-13

Endothelin-1 (ET-1) is unique among a broad range of hyperalgesic agents in that it induces hyperalgesia in rats that is markedly enhanced by repeated mechanical stimulation at the site of administration. Antagonists to the ET-1 receptors, ET(A) and ET(B), attenuated both initial as well as stimulation-induced enhancement of hyperalgesia (SIEH) by endothelin. However, administering antisense oligodeoxynucleotide to attenuate ET(A) receptor expression on nociceptors attenuated ET-1 hyperalgesia but had no effect on SIEH, suggesting that this is mediated via a non-neuronal cell. Because vascular endothelial cells are both stretch sensitive and express ET(A) and ET(B) receptors, we tested the hypothesis that SIEH is dependent on endothelial cells by impairing vascular endothelial function with octoxynol-9 administration; this procedure eliminated SIEH without attenuating ET-1 hyperalgesia. A role for protein kinase Cε (PKCε), a second messenger implicated in the induction and maintenance of chronic pain, was explored. Intrathecal antisense for PKCε did not inhibit either ET-1 hyperalgesia or SIEH, suggesting no role for neuronal PKCε; however, administration of a PKCε inhibitor at the site of testing selectively attenuated SIEH. Compatible with endothelial cells releasing ATP in response to mechanical stimulation, P2X(2/3) receptor antagonists eliminated SIEH. The endothelium also appears to contribute to hyperalgesia in two ergonomic pain models (eccentric exercise and hindlimb vibration) and in a model of endometriosis. We propose that SIEH is produced by an effect of ET-1 on vascular endothelial cells, sensitizing its release of ATP in response to mechanical stimulation; ATP in turn acts at the nociceptor P2X(2/3) receptor.

Effect of radiation-induced heart injury on content of cardiac troponin I and endothelin-1 in SD rats

International Nuclear Information System (INIS)

Xu Jiuhong; Gao Yaoming; Zhang Junning; Li Xinli

2011-01-01

Objective: To investigate the effect of radiation-induced heart injury (RIHD) on cardiac endothelin-1 (ET-1) and cardiac troponin I (cTnI) in SD rats, and the possibility regarding ET-1 and cTnI as biomarker of RIHD was also explored. Methods: Healthy female SD rats were randomly divided into two groups: the control group (C) and irradiation group (R). The rats in R group were irradiated with linear accelerator at a single dose of 25 Gy. Five milliliters blood was collected from the inferior vena cava on the 5th, 15th, 30th, 60th day after radiation. Blood was centrifuged and serum was collected. Content of ET-1 and cTnI in blood serum were detected by ELISA kits. Results: The content of ET-1 in the R group was always higher than that in the C group (P<0.01) during the whole process, and the difference between two groups had statistical significance only on the 5th day (P<0.01) and 15th day (P<0.05) after radiation. However, the content of cTnI in R group was higher than that in the C group within 30 days after radiation, then decreased, and only on the 15th day (P<0.05) and the 30th day (P<0.01) after radiation, there was statistical difference between two groups. Conclusion: The content of ET-1 and cTnI in blood serum increase obviously after receiving RIHD, so these two indicators can be used as markers to diagnose early RIHD sensitively and specifically. (authors)

Normalization of hemoglobin-based oxygen carrier-201 induced vasoconstriction: targeting nitric oxide and endothelin.

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Taverne, Yannick J; de Wijs-Meijler, Daphne; Te Lintel Hekkert, Maaike; Moon-Massat, Paula F; Dubé, Gregory P; Duncker, Dirk J; Merkus, Daphne

2017-05-01

Hemoglobin-based oxygen carrier (HBOC)-201 is a cell-free modified hemoglobin solution potentially facilitating oxygen uptake and delivery in cardiovascular disorders and hemorrhagic shock. Clinical use has been hampered by vasoconstriction in the systemic and pulmonary beds. Therefore, we aimed to 1 ) determine the possibility of counteracting HBOC-201-induced pressor effects with either adenosine (ADO) or nitroglycerin (NTG); 2 ) assess the potential roles of nitric oxide (NO) scavenging, reactive oxygen species (ROS), and endothelin (ET) in mediating the observed vasoconstriction; and 3 ) compare these effects in resting and exercising swine. Chronically instrumented swine were studied at rest and during exercise after administration of HBOC-201 alone or in combination with ADO. The role of NO was assessed by supplementation with NTG or administration of the eNOS inhibitor N ω -nitro-l-arginine. Alternative vasoactive pathways were investigated via intravenous administration of the ET A /ET B receptor blocker tezosentan or a mixture of ROS scavengers. The systemic and to a lesser extent the pulmonary pressor effects of HBOC-201 could be counteracted by ADO; however, dosage titration was very important to avoid systemic hypotension. Similarly, supplementation of NO with NTG negated the pressor effects but also required titration of the dose. The pressor response to HBOC-201 was reduced after eNOS inhibition and abolished by simultaneous ET A /ET B receptor blockade, while ROS scavenging had no effect. In conclusion, the pressor response to HBOC-201 is mediated by vasoconstriction due to NO scavenging and production of ET. Further research should explore the effect of longer-acting ET receptor blockers to counteract the side effect of hemoglobin-based oxygen carriers. NEW & NOTEWORTHY Hemoglobin-based oxygen carrier (HBOC)-201 can disrupt hemodynamic homeostasis, mimicking some aspects of endothelial dysfunction, resulting in elevated systemic and pulmonary blood

Endothelin-like action of Pausinystalia yohimbe aqueous extract on vascular and renal regional hemodynamics in Sprague Dawley rats.

Science.gov (United States)

Ajayi, A A; Newaz, M; Hercule, H; Saleh, M; Bode, C O; Oyekan, A O

2003-12-01

The bark of the African tree Pausinystalia yohimbe has been used as a food additive with aphrodisiac and penile erection enhancing properties. The effect of an aqueous extract of P. yohimbe (CCD-X) on renal circulation was assessed in order to test the hypothesis that it possesses additional effects on nitric oxide production and/or endothelin-1 (ET-1)-like actions. In vivo studies with CCD-X in Sprague Dawley rats demonstrated a dose-dependent (1-1000 ng/kg) increase in mean blood pressure (p < 0.001) and an increase in medullary blood flow (MBF) (p < 0.001). Both the pressor action and renal medullary vasodilation were blocked by endothelinA (ETA) receptor antagonist BMS182874 and endothelinB (ETB) receptor antagonist BQ788 in combination. L-Nomega-nitro-l-arginine methyl ester (L-NAME; 10 mg/kg) also inhibited the increase in MBF induced by CCD-X. In vitro studies in isolated perfused kidney and in pressurized renal microvessels confirmed the dose-dependent vasoconstrictor action of this extract. ETA receptor antagonist BQ610 and ETB receptor antagonist BQ788 separately and significantly attenuated the renal vasoconstrictor actions of the extract (p < 0.001 ANOVA). These preliminary observations indicate that, in addition to the alpha-adrenergic antagonist actions that characterize yohimbine, CCD-X possesses endothelin-like actions and affects nitric oxide (NO) production in renal circulation. These findings suggest a strong possibility of post-receptor cross-talk between alpha2-adrenoceptors and endothelin, as well as a direct effect of alpha2-adrenoceptors on renal NO production. (c) 2003 Prous Science

A sensitive radioimmunoassay measuring endothelin-like immunoreactivity in human plasma: comparison of levels in patients with essential hypertension and normotensive control subjects

International Nuclear Information System (INIS)

Davenport, A.P.; Ashby, M.J.; Easton, Patricia

1990-01-01

A radioimmunoassay was developed to measure endothelin-like immunoreactivity in human plasma using antibody raised against endothelin-1 which also cross-reacts with big endothelin-1 and endothelin-2 but not endothelin-3. The sensitivity was 1 fmol/tube with inter- and intra-assay coefficients of variation of 13% and 9%, respectively. Cross-reactivity with endothelin-3 and non-endothelin peptides was less than 1%. Endothelin-like immunoreactivity was present in plasma of hypertensive patients (n = 25) at 5.7±0.5 pmol/1 (mean±SEM), not significantly different from that of age-matched control subjects (5.1±0.5 pmol/1). At these levels, endothelin-1 is unlikely to function as a circulating hormone. In the normotensive group, the concentration of endothelin-like immunoreactivity in plasma was positively correlated with mean arterial blood pressure, but in hypertensive patients it showed significant negative correlation. (author)

Endothelin-1 exacerbates development of hypertension and atherosclerosis in modest insulin resistant syndrome

International Nuclear Information System (INIS)

Lin, Yan-Jie; Juan, Chi-Chang; Kwok, Ching-Fai; Hsu, Yung-Pei; Shih, Kuang-Chung; Chen, Chin-Chang; Ho, Low-Tone

2015-01-01

Endothelin-1 (ET-1) is known as potent vasoconstrictor, by virtue of its mitogenic effects, and may deteriorate the process of hypertension and atherosclerosis by aggravating hyperplasia and migration in VSMCs. Our previous study demonstrated that insulin infusion caused sequential induction of hyperinsulinemia, hyperendothelinemia, insulin resistance, and then hypertension in rats. However, the underlying mechanism of ET-1 interfere insulin signaling in VSMCs remains unclear. To characterize insulin signaling during modest insulin resistant syndrome, we established and monitored rats by feeding high fructose-diet (HFD) until high blood pressure and modest insulin resistance occurred. To explore the role of ET-1/ET A R during insulin resistance, ET A R expression, ET-1 binding, and insulin signaling were investigated in the HFD-fed rats and cultured A-10 VSMCs. Results showed that high blood pressure, tunica medial wall thickening, plasma ET-1 and insulin, and accompanied with modest insulin resistance without overweight and hyperglycemia occurred in early-stage HFD-fed rats. In the endothelium-denuded aorta from HFD-fed rats, ET A R expression, but not ET B R, and ET-1 binding in aorta were increased. Moreover, decreasing of insulin-induced Akt phosphorylation and increasing of insulin-induced ERK phosphorylation were observed in aorta during modest insulin resistance. Interestingly, in ET-1 pretreated VSMCs, the increment of insulin-induced Akt phosphorylation was decreased whereas the increment of insulin-induced ERK phosphorylation was increased. In addition, insulin potentiated ET-1-induced VSMCs migration and proliferation due to increasing ET-1 binding. ETAR antagonist reversed effects of ET-1 on insulin-induced signaling and VSMCs migration and proliferation. In summary, modest insulin resistance syndrome accompanied with hyperinsulinemia leading to the potentiation on ET-1-induced actions in aortic VSMCs. ET-1 via ET A R pathway suppressed insulin-induced

Diet-Induced Ketosis Protects Against Focal Cerebral Ischemia in Mouse.

Science.gov (United States)

Xu, Kui; Ye, Lena; Sharma, Katyayini; Jin, Yongming; Harrison, Matthew M; Caldwell, Tylor; Berthiaume, Jessica M; Luo, Yu; LaManna, Joseph C; Puchowicz, Michelle A

2017-01-01

Over the past decade we have consistently shown that ketosis is neuroprotective against ischemic insults in rats. We reported that diet-induced ketotic rats had a significant reduction in infarct volume when subjected to middle cerebral artery occlusion (MCAO), and improved survival and recovery after cardiac arrest and resuscitation. The neuroprotective mechanisms of ketosis (via ketogenic diet; KG) include (i) ketones are alternate energy substrates that can restore energy balance when glucose metabolism is deficient and (ii) ketones modulate cell-signalling pathways that are cytoprotective. We investigated the effects of diet-induced ketosis following transient focal cerebral ischemia in mice. The correlation between levels of ketosis and hypoxic inducible factor-1alpha (HIF-1α), AKT (also known as protein kinase B or PKB) and 5' AMP-activated protein kinase (AMPK) were determined. Mice were fed with KG diet or standard lab-chow (STD) diet for 4 weeks. For the MCAO group, mice underwent 60 min of MCAO and total brain infarct volumes were evaluated 48 h after reperfusion. In a separate group of mice, brain tissue metabolites, levels of HIF-1α, phosphorylated AKT (pAKT), and AMPK were measured. After feeding a KG diet, levels of blood ketone bodies (beta-hydroxyburyrate, BHB) were increased. There was a proportional decrease in infarct volumes with increased blood BHB levels (KG vs STD; 4.2 ± 0.6 vs 7.8 ± 2.2 mm 3 , mean ± SEM). A positive correlation was also observed with HIF-1α and pAKT relative to blood BHB levels. Our results showed that chronic ketosis can be induced in mice by KG diet and was neuroprotective against focal cerebral ischemia in a concentration dependent manner. Potential mechanisms include upregulation of cytoprotective pathways such as those associated with HIF-1α, pAKT and AMPK.

Endothelin-1 in systemic sclerosis

Directory of Open Access Journals (Sweden)

C. Pizzorni

2011-09-01

Full Text Available We evaluated endothelin-1 (ET-1 plasma levels in patients affected by primary Raynaud’s phenomenon (PRP, as well as in patients with systemic sclerosis (SSc and secondary Raynaud’s phenomenon (SRP. Furthermore, ET-1 levels were investigated in SSc patients with different patterns of peripheral microvascular damage, as evaluated by nailfold videocapillaroscopy (NVC. Methods: 23 PRP patients, 67 SSc patients according to ACR criteria, and 23 healthy subjects were enrolled. SSc microvascular involvement was classified in three different patterns (Early, Active, and Late by NVC, as previously described. Results: ET-1 was found significantly higher in both PRP and SRP, when compared with controls (median ±IQR: 3.3±2.8, 2.7±2.2, 2.0±2.2, respectively (p=0.05. No statistically significant difference of ET-1 levels was observed between PRP and SRP patients. ET-1 was found higher in patients with Late NVC pattern, when compared with both Active and Early NVC patterns (median±IQR: 3.4±2.5, 2.4±2.2, 2.5±2.1, respectively, but without statistical significance. Patients with Late NVC pattern showed significantly higher ET-1 plasma levels than controls (p=0.03. No correlation was found between ET-1 levels and disease duration in both groups, as well as between ET-1 levels and age of patients. Conclusions: These data support previous studies, reporting increased ET-1 plasma levels in both PRP and SRP patients. Interestingly, patients with the Late NVC pattern of microangiopathy showed higher ET-1 plasma levels than controls. The high levels of ET-1 detected in the Late NVC pattern of microangiopathy might be related to the larger fibrotic involvement typical of the advanced stages of disease.

Resveratrol inhibits the intracellular calcium increase and angiotensin/endothelin system activation induced by soluble uric acid in mesangial cells

Energy Technology Data Exchange (ETDEWEB)

Albertoni, G.; Schor, N. [Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

2014-10-24

Resveratrol (Resv) is natural polyphenol found in grapes. This study evaluated the protective effect of Resv against the effects of uric acid (UA) in immortalized human mesangial cells (ihMCs). ihMCs were preincubated with Resv (12.5 µM) for 1 h and treated with UA (10 mg/dL) for 6 or 12 h. The intracellular calcium concentration [Ca{sup 2+}]i was quantified by fluorescence using flow cytometry. Angiotensinogen (AGT) and pre-pro endothelin-1 (ppET-1) mRNA were assayed by quantitative real-time RT-PCR. Angiotensin II (AII) and endothelin-1 (ET-1) were assayed by ELISA. UA significantly increased [Ca{sup 2+}]i. Pre-incubation with Resv significantly reduced the change in [Ca{sup 2+}]i induced by UA. Incubation with UA for 6 or 12 h also increased AGT mRNA expression and AII protein synthesis. Resv blunted these increases in AGT mRNA expression and AII protein. Incubation with UA in the ihMCs increased ppET-1 expression and ET-1 protein synthesis at 6 and 12 h. When ihMCs were pre-incubated with Resv, UA had a significantly diminished effect on ppET-1 mRNA expression and ET-1 protein synthesis at 6 and 12 h, respectively. Our results suggested that UA triggers reactions including AII and ET-1 production in mesangial cells. The renin-angiotensin system may contribute to the pathogenesis of renal function and chronic kidney disease. Resv can minimize the impact of UA on AII, ET-1 and the increase of [Ca{sup 2+}]i in mesangial cells, suggesting that, at least in part, Resv can prevent the effects of soluble UA in mesangial cells.

Efecto de la endotelina-1 sobre las arterias tumorales de pacientes con neoplasia colorrectal Effect of endothelin-1 on tumor arteries in patients with colorectal cancer

Directory of Open Access Journals (Sweden)

E. Ferrero Herrero

2008-06-01

Full Text Available La endotelina-1 es un péptido vasoconstrictor producido por el endotelio vascular, cuyos niveles plasmáticos están aumentados en los pacientes con cáncer colorrectal y que puede participar en la regulación del flujo sanguíneo tumoral. Para estudiar si la respuesta a este péptido está alterada en las arterias tumorales, se obtuvieron, de 13 pacientes intervenidos quirúrgicamente por cáncer colorrectal, arterias mesentéricas irrigando el tumor y arterias mesentéricas de una región alejada del tumor, y asimismo se obtuvieron arterias mesentéricas de pacientes intervenidos por diverticulitis (n = 4 o enfermedad inflamatoria intestinal (n = 3. Las arterias mesentéricas se montaron en una preparación para el registro de la contracción isométrica en un baño de órganos, encontrándose que la endotelina-1 producía contracción en los tres tipos de arterias, pero la sensibilidad a este péptido fue mayor en las arterias irrigando el tumor que en las arterias alejadas del tumor o en las arterias de pacientes sin patología tumoral. Estos resultados indican que la endotelina-1 puede regular el flujo sanguíneo en los tumores colorrectales, produciendo una mayor vasoconstricción en las arterias que irrigan el tumor que en las arterias no tumorales.Endothelin-1 is an endothelium-derived vasoconstrictor peptide whose plasma levels are increased in patients with colorectal cancer, and which may be involved in tumor blood flow regulation. To study whether response to this peptide is altered in tumor arteries, mesenteric arteries supplying blood flow to colorectal tumors, and mesenteric arteries far from said tumors were obtained from 13 patients undergoing colectomy; mesenteric arteries were also obtained from patients with diverticulitis (n = 4 or inflammatory bowel disease (n = 3. Arteries were prepared for isometric tension recording in an organ bath, and in this preparation it was found that endothelin-1 induced contraction in all three

The Effects of Repeated Rehabilitation “Tune-Ups” on Functional Recovery After Focal Ischemia in Rats

DEFF Research Database (Denmark)

Clarke, Jared; Rytter, Hana Malá; Windle, Victoria

2009-01-01

of stroke recovery. Methods. Rats were exposed to focal ischemia (endothelin-1 applied to forelimb sensorimotor cortex and dorsolateral striatum) and allowed to recover either in standard housing or in a combination of enriched environment and rehabilitative reaching for 9 weeks. Animals were then exposed...... complexity in the contralesional forelimb motor cortex. Results. Although early enriched rehabilitation significantly improved sensorimotor function in both the beam and staircase tests, “tune-up” therapy had no effect on recovery. Golgi–Cox analysis revealed no effect of treatment on dendritic complexity...

Myoendothelial coupling in the mesenteric arterial bed; segmental differences and interplay between nitric oxide and endothelin-1

Science.gov (United States)

Hilgers, RHP; De Mey, JGR

2009-01-01

Background and purpose: We tested the hypothesis that activated arterial smooth muscle (ASM) stimulates endothelial vasomotor influences via gap junctions and that the significance of this myoendothelial coupling increases with decreasing arterial diameter. Experimental approach: From WKY rats, first-, second-, third-and fourth-order branches of the superior mesenteric artery (MA1, MA2, MA3 and MA4 respectively) were isolated and mounted in wire-myographs to record vasomotor responses to 0.16–20 µmol·L−1 phenylephrine. Key results: Removal of endothelium increased the sensitivity (pEC50) to phenylephrine in all arteries. The nitric oxide (NO) synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME) (100 µmol·L−1) did not modify pEC50 to phenylephrine in all denuded arteries, and increased it in intact MA1, MA2 and MA3 to the same extent as denudation. However, in intact MA4, the effect of L-NAME was significantly larger (ΔpEC50 0.57 ± 0.02) than the effect of endothelium removal (ΔpEC50 0.20 ± 0.06). This endothelium-dependent effect of L-NAME in MA4 was inhibited by (i) steroidal and peptidergic uncouplers of gap junctions; (ii) a low concentration of the NO donor sodium nitroprusside; and (iii) by the endothelin-receptor antagonist bosentan. It was also observed during contractions induced by (i) calcium channel activation (BayK 8644, 0.001–1 µmol·L−1); (ii) depolarization (10–40 mmol·L−1 K+); and (iii) sympathetic nerve stimulation (0.25–32 Hz). Conclusions and implications: These pharmacological observations indicated feedback control by endothelium of ASM reactivity involving gap junctions and a balance between endothelium-derived NO and endothelin-1. This myoendothelial coupling was most prominent in distal resistance arteries. PMID:19302591

Elevated levels of plasma Big endothelin-1 and its relation to hypertension and skin lesions in individuals exposed to arsenic

International Nuclear Information System (INIS)

Hossain, Ekhtear; Islam, Khairul; Yeasmin, Fouzia; Karim, Md. Rezaul; Rahman, Mashiur; Agarwal, Smita; Hossain, Shakhawoat; Aziz, Abdul; Al Mamun, Abdullah; Sheikh, Afzal; Haque, Abedul; Hossain, M. Tofazzal; Hossain, Mostaque; Haris, Parvez I.; Ikemura, Noriaki; Inoue, Kiyoshi; Miyataka, Hideki; Himeno, Seiichiro; Hossain, Khaled

2012-01-01

Chronic arsenic (As) exposure affects the endothelial system causing several diseases. Big endothelin-1 (Big ET-1), the biological precursor of endothelin-1 (ET-1) is a more accurate indicator of the degree of activation of the endothelial system. Effect of As exposure on the plasma Big ET-1 levels and its physiological implications have not yet been documented. We evaluated plasma Big ET-1 levels and their relation to hypertension and skin lesions in As exposed individuals in Bangladesh. A total of 304 study subjects from the As-endemic and non-endemic areas in Bangladesh were recruited for this study. As concentrations in water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The plasma Big ET-1 levels were measured using a one-step sandwich enzyme immunoassay kit. Significant increase in Big ET-1 levels were observed with the increasing concentrations of As in drinking water, hair and nails. Further, before and after adjusting with different covariates, plasma Big ET-1 levels were found to be significantly associated with the water, hair and nail As concentrations of the study subjects. Big ET-1 levels were also higher in the higher exposure groups compared to the lowest (reference) group. Interestingly, we observed that Big ET-1 levels were significantly higher in the hypertensive and skin lesion groups compared to the normotensive and without skin lesion counterpart, respectively of the study subjects in As-endemic areas. Thus, this study demonstrated a novel dose–response relationship between As exposure and plasma Big ET-1 levels indicating the possible involvement of plasma Big ET-1 levels in As-induced hypertension and skin lesions. -- Highlights: ► Plasma Big ET-1 is an indicator of endothelial damage. ► Plasma Big ET-1 level increases dose-dependently in arsenic exposed individuals. ► Study subjects in arsenic-endemic areas with hypertension have elevated Big ET-1 levels. ► Study subjects with arsenic-induced

Elevated levels of plasma Big endothelin-1 and its relation to hypertension and skin lesions in individuals exposed to arsenic

Energy Technology Data Exchange (ETDEWEB)

Hossain, Ekhtear; Islam, Khairul; Yeasmin, Fouzia [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh); Karim, Md. Rezaul [Department of Applied Nutrition and Food Technology, Islamic University, Kushtia-7003 (Bangladesh); Rahman, Mashiur; Agarwal, Smita; Hossain, Shakhawoat; Aziz, Abdul; Al Mamun, Abdullah; Sheikh, Afzal; Haque, Abedul; Hossain, M. Tofazzal [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh); Hossain, Mostaque [Department of Medicine, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), Dhaka (Bangladesh); Haris, Parvez I. [Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH (United Kingdom); Ikemura, Noriaki; Inoue, Kiyoshi; Miyataka, Hideki; Himeno, Seiichiro [Laboratory of Molecular Nutrition and Toxicology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima 770–8514 (Japan); Hossain, Khaled, E-mail: khossain69@yahoo.com [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)

2012-03-01

Chronic arsenic (As) exposure affects the endothelial system causing several diseases. Big endothelin-1 (Big ET-1), the biological precursor of endothelin-1 (ET-1) is a more accurate indicator of the degree of activation of the endothelial system. Effect of As exposure on the plasma Big ET-1 levels and its physiological implications have not yet been documented. We evaluated plasma Big ET-1 levels and their relation to hypertension and skin lesions in As exposed individuals in Bangladesh. A total of 304 study subjects from the As-endemic and non-endemic areas in Bangladesh were recruited for this study. As concentrations in water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The plasma Big ET-1 levels were measured using a one-step sandwich enzyme immunoassay kit. Significant increase in Big ET-1 levels were observed with the increasing concentrations of As in drinking water, hair and nails. Further, before and after adjusting with different covariates, plasma Big ET-1 levels were found to be significantly associated with the water, hair and nail As concentrations of the study subjects. Big ET-1 levels were also higher in the higher exposure groups compared to the lowest (reference) group. Interestingly, we observed that Big ET-1 levels were significantly higher in the hypertensive and skin lesion groups compared to the normotensive and without skin lesion counterpart, respectively of the study subjects in As-endemic areas. Thus, this study demonstrated a novel dose–response relationship between As exposure and plasma Big ET-1 levels indicating the possible involvement of plasma Big ET-1 levels in As-induced hypertension and skin lesions. -- Highlights: ► Plasma Big ET-1 is an indicator of endothelial damage. ► Plasma Big ET-1 level increases dose-dependently in arsenic exposed individuals. ► Study subjects in arsenic-endemic areas with hypertension have elevated Big ET-1 levels. ► Study subjects with arsenic-induced

Endothelin-1 exacerbates development of hypertension and atherosclerosis in modest insulin resistant syndrome

Energy Technology Data Exchange (ETDEWEB)

Lin, Yan-Jie [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan (China); Juan, Chi-Chang [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Kwok, Ching-Fai [Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Hsu, Yung-Pei [Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan (China); Shih, Kuang-Chung [Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Chen, Chin-Chang [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Ho, Low-Tone, E-mail: ltho@vghtpe.gov.tw [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan (China)

2015-05-08

Endothelin-1 (ET-1) is known as potent vasoconstrictor, by virtue of its mitogenic effects, and may deteriorate the process of hypertension and atherosclerosis by aggravating hyperplasia and migration in VSMCs. Our previous study demonstrated that insulin infusion caused sequential induction of hyperinsulinemia, hyperendothelinemia, insulin resistance, and then hypertension in rats. However, the underlying mechanism of ET-1 interfere insulin signaling in VSMCs remains unclear. To characterize insulin signaling during modest insulin resistant syndrome, we established and monitored rats by feeding high fructose-diet (HFD) until high blood pressure and modest insulin resistance occurred. To explore the role of ET-1/ET{sub A}R during insulin resistance, ET{sub A}R expression, ET-1 binding, and insulin signaling were investigated in the HFD-fed rats and cultured A-10 VSMCs. Results showed that high blood pressure, tunica medial wall thickening, plasma ET-1 and insulin, and accompanied with modest insulin resistance without overweight and hyperglycemia occurred in early-stage HFD-fed rats. In the endothelium-denuded aorta from HFD-fed rats, ET{sub A}R expression, but not ET{sub B}R, and ET-1 binding in aorta were increased. Moreover, decreasing of insulin-induced Akt phosphorylation and increasing of insulin-induced ERK phosphorylation were observed in aorta during modest insulin resistance. Interestingly, in ET-1 pretreated VSMCs, the increment of insulin-induced Akt phosphorylation was decreased whereas the increment of insulin-induced ERK phosphorylation was increased. In addition, insulin potentiated ET-1-induced VSMCs migration and proliferation due to increasing ET-1 binding. ETAR antagonist reversed effects of ET-1 on insulin-induced signaling and VSMCs migration and proliferation. In summary, modest insulin resistance syndrome accompanied with hyperinsulinemia leading to the potentiation on ET-1-induced actions in aortic VSMCs. ET-1 via ET{sub A}R pathway

The observation on plasma endothelin levels in patients with graves' disease

International Nuclear Information System (INIS)

Hao Xiaojun; Liu Changshan; Yang Lianrong; Zhang Qiliang; Wang Honggang; Liu Xudong

2002-01-01

Observing the plasma endothelin levels in patients with Graves' disease to probe its clinical significance, plasma endothelin levels were measured in 55 cases of Graves' disease before and after treatment respectively, and these were compared with that of 23 health subjects. Results: plasma endothelin levels in patients with Graves' disease significantly increase, compared with heath subjects (150.4 +- 29.31 ng/L vs 42.80 +- 7.58 ng/L, P < 0.01); post-treatment endothelin levels apparently decrease (97.61 +- 15.99 ng/L vs 150.4 +- 29.31 ng/L, P < 0.01). Plasma endothelin levels in patients with Graves' disease significantly increase, and after treatment the endothelin levels decrease following decreasing of thyroid hormone level and high hemodynamics

Increased calcineurin expression after pilocarpine-induced status epilepticus is associated with brain focal edema and astrogliosis.

Science.gov (United States)

Liu, Jinzhi; Li, Xiaolin; Chen, Liguang; Xue, Ping; Yang, Qianqian; Wang, Aihua

2015-07-28

Calcineurin plays an important role in the development of neuronal excitability, modulation of receptor's function and induction of apoptosis in neurons. It has been established in kindling models that status epilepticus induces brain focal edema and astrocyte activation. However, the role of calcineurin in brain focal edema and astrocyte activation in status epilepticus has not been fully understood. In this study, we employed a model of lithium-pilocarpine-induced status epilepticus and detected calcineurin expression in hippocampus by immunoblotting, brain focal edema by non-invasive magnetic resonance imaging (MRI-7T) and astrocyte expression by immunohistochemistry. We found that the brain focal edema was seen at 24 h after status epilepticus, and astrocyte expression was obviously seen at 7 d after status epilepticus. Meanwhile, calcineurin expression was seen at24 h and retained to 7 d after status epilepticus. A FK506, a calcineurin inhibitor, remarkably suppressed the status epilepticus-induced brain focal edema and astrocyte expression. Our data suggested that calcineurin overexpression plays a very important role in brain focal edema and astrocyte expression. Therefore, calcineurin may be a novel candidate for brain focal edema occurring and intracellular trigger of astrogliosis in status epilepticus.

Investigating the Et-1/SphK/S1P Pathway as a Novel Approach for the Prevention of Inflammation-Induced Preterm Birth.

Science.gov (United States)

Giusto, Kiersten; Ashby, Charles R

2018-01-30

Preterm birth (PTB), defined as birth before 37 completed weeks of gestation, occurs in up to 18 percent of births worldwide and accounts for the majority of perinatal morbidity and mortality. While the single most common cause of PTB has been identified as inflammation, safe and effective pharmacotherapy to prevent PTB has yet to be developed. Our group has used an in vivo model of inflammation driven PTB, biochemical methods, pharmacological approaches, a novel endothelin receptor antagonist that we synthesized and RNA knockdown to help establish the role of endothelin-1 (ET-1) in inflammation-associated PTB. Further, we have used our in vivo model to test whether sphingosine kinase, which acts downstream of ET-1, plays a role in PTB. We have shown that levels of endothelin converting enzyme-1 (ECE-1) and ET-1 are increased when PTB is induced in timed pregnant mice with lipopolysaccharide (LPS) and that blocking ET-1 action, pharmacologically or using ECE-1 RNA silencing, rescues LPS-induced mice from PTB. ET-1 activates the sphingosine kinase/sphingosine-1-phosphate (SphK/S1P) pathway. S1P, in turn, is an important signaling molecule in the pro-inflammatory response. Interestingly, we have shown that SphK inhibition also prevents LPS-induced PTB in timed pregnant mice. Further, we showed that SphK inhibition suppresses the ECE-1/ET-1 axis, implicating positive feedback regulation of the SphK/S1P/ECE-1/ET-1 axis. The ET-1/SphK/SIP pathway is a potential pharmacotherapeutic target for the prevention of PTB. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Effect of endothelin-1 on the excitability of rat cortical and hippocampal slices in vitro

Czech Academy of Sciences Publication Activity Database

Konopková, Renata; Világi, I.; Borbély, S.; Kubová, Hana; Otáhal, Jakub

2012-01-01

Roč. 61, č. 2 (2012), s. 215-219 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) LC554; GA AV ČR(CZ) 1QS501210509; GA ČR(CZ) GD305/08/H037 Institutional research plan: CEZ:AV0Z50110509 Keywords : Endothelin-1 * excitability * hippocampus * somatosensory cortex * rat * epileptogenesis Subject RIV: FH - Neurology Impact factor: 1.531, year: 2012

The mechanism of action of endothelin-1 as compared with other agonists in vascular smooth muscle

International Nuclear Information System (INIS)

Wallnoefer, A.W.; Weir, S.; Rueegg, U.C.; Cauvin, C.

1989-01-01

The effects of endothelin-1 (ET-1) on tension and membrane potential in rat isolated mesenteric resistance vessels (MRVs) and on 45Ca influx, 45Ca efflux, inositol-1,4,5-triphosphate (IP3) production, and cytoplasmic Ca2+ concentration ([Ca2+]1) in cultured aortic smooth muscle cells were compared with those of other agonists. ET-1 induced contractions of the MRVs, which were slow in onset, but reached a similar maximum amplitude (at 10 nM ET-1) as that seen with norepinephrine (NE, 10 microM) or [arg8]vasopressin (AVP, 0.1 microM). The EC50 for ET-1 was 1.3 +/- 0.1 nM. Removal of extracellular Ca2+ reduced ET-1-induced contractions to 11 +/- 3% of those in Ca2+-containing medium. With NE, the same procedure reduced contractions to 47 +/- 7% of those in Ca2+-containing medium, while with AVP, the reduction was similar in magnitude to that induced by ET-1 (11 +/- 5% of those in Ca2+-containing medium). Relaxation of ET-1-induced and NE-induced contractions by diltiazem was not complete (maximal at 58 +/- 6% with 10 microM diltiazem after 6 nM ET-1, and at 70 +/- 3% after 0.1 microM NE), in contrast to that of 80 mM K+-induced contractions, which were potently (IC50 = 0.2 microM) and completely reversed (100% relaxation at 10 microM diltiazem). ET-1 (6 nM) caused a small but significant depolarization of the MRVs (approximately 7 mV), the magnitude of which was only about one-third of that induced by equieffective contractile concentrations of NE and AVP. The voltage-sensitive Ca2+ channel agonist Bay K 8644 (1 microM), in contrast to ET-1, NE, and AVP, produced a small contraction (30 +/- 2% of the maximum response to NE), but no further depolarization when added in the presence of 15 mM K+ (which elicited approximately 12 mV depolarization but no contraction)

Targeting the ROS-HIF-1-endothelin axis as a therapeutic approach for the treatment of obstructive sleep apnea-related cardiovascular complications

Science.gov (United States)

Belaidi, Elise; Morand, Jessica; Gras, Emmanuelle; Pépin, Jean-Louis; Godin-Ribuot, Diane

2016-01-01

Obstructive sleep apnea (OSA) is now recognized as an independent and important risk factor for cardiovascular diseases such as hypertension, coronary heart disease, heart failure and stroke. Clinical and experimental data have confirmed that intermittent hypoxia is a major contributor to these deleterious consequences. The repetitive occurrence of hypoxia-reoxygenation sequences generates significant amounts of free radicals, particularly in moderate to severe OSA patients. Moreover, in addition to hypoxia, reactive oxygen species (ROS) are potential inducers of the hypoxia inducible transcription factor-1 (HIF-1) that promotes the transcription of numerous adaptive genes some of which being deleterious for the cardiovascular system, such as the endothelin-1 gene. This review will focus on the involvement of the ROS-HIF-1-endotelin signaling pathway in OSA and intermittent hypoxia and discuss current and potential therapeutic approaches targeting this pathway to treat or prevent cardiovascular disease in moderate to severe OSA patients. PMID:27492897

Polyphenol fraction of extra virgin olive oil protects against endothelial dysfunction induced by high glucose and free fatty acids through modulation of nitric oxide and endothelin-1

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Carolina Emilia Storniolo

2014-01-01

Full Text Available Epidemiological and clinical studies have reported that olive oil reduces the incidence of cardiovascular disease. However, the mechanisms involved in this beneficial effect have not been delineated. The endothelium plays an important role in blood pressure regulation through the release of potent vasodilator and vasoconstrictor agents such as nitric oxide (NO and endothelin-1 (ET-1, respectively, events that are disrupted in type 2 diabetes. Extra virgin olive oil contains polyphenols, compounds that exert a biological action on endothelial function. This study analyzes the effects of olive oil polyphenols on endothelial dysfunction using an in vitro model that simulates the conditions of type 2 diabetes. Our findings show that high glucose and linoleic and oleic acids decrease endothelial NO synthase phosphorylation, and consequently intracellular NO levels, and increase ET-1 synthesis by ECV304 cells. These effects may be related to the stimulation of reactive oxygen species production in these experimental conditions. Hydroxytyrosol and the polyphenol extract from extra virgin olive oil partially reversed the above events. Moreover, we observed that high glucose and free fatty acids reduced NO and increased ET-1 levels induced by acetylcholine through the modulation of intracellular calcium concentrations and endothelial NO synthase phosphorylation, events also reverted by hydroxytyrosol and polyphenol extract. Thus, our results suggest a protective effect of olive oil polyphenols on endothelial dysfunction induced by hyperglycemia and free fatty acids.

Steroid-induced polycystic ovaries in rats: effect of electro-acupuncture on concentrations of endothelin-1 and nerve growth factor (NGF, and expression of NGF mRNA in the ovaries, the adrenal glands, and the central nervous system

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Aloe Luigi

2003-04-01

Full Text Available Abstract Previous studies on the effect of repeated electro-acupuncture (EA treatments in rats with steriod-induced polycystic ovaries (PCO, EA has been shown to modulate nerve growth factor (NGF concentration in the ovaries as well as corticotropin releasing factor (CRF in the median eminence (ME. In the present study we tested the hypothesis that repeated EA treatments modulates sympathetic nerve activity in rats with PCO. This was done by analysing endothelin-1 (ET-1, a potent vasoconstrictor involved in ovarian functions, as well as NGF and NGF mRNA expression involved in the pathophysiological process underlying steroid-induced PCO. The main result in the present study was that concentrations of ET-1 in the ovaries were significantly lower in the PCO group receiving EA compared with the healthy control group (p p p p

Endothelin-1 and Exercise Intensity in Sedentary Adolescents with Obesity

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Brooke E. Starkoff

2015-01-01

Full Text Available Inactivity combined with obesity during adolescence increases the risk of future cardiovascular disease. The study purpose was to compare the influence of differing intensities of exercise on endothelial function in sedentary adolescents with obesity. Participants were randomized to one of two groups in a 6-week exercise intervention: moderate intensity (MOD or high intensity interval exercise (HIIE. Endothelial function was assessed pre- and post-intervention via fasted serum levels of endothelin-1 (ET-1. Pre-measures of ET-1 concentrations were elevated at baseline. No significant differences in ET-1 were found between or within exercise groups. However, in the HIIE group, ET-1 was inversely associated with percentages of age predicted maximal heart rate achieved during the intervention (p=0.035, r=-0.567. The exercise interventions did not positively change ET-1 levels, yet participants who exercised at higher intensities in the HIIE group experienced greater decreases in ET-1. Keywords: childhood obesity, endothelial function, high intensity interval exercise

Association of endothelin-1 expression and cartilaginous endplate degeneration in humans.

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Wei Yuan

Full Text Available BACKGROUND: Inflammatory cytokines are involved in intervertebral disc (IVD degeneration. Endothelin-1 (ET-1, a 21-amino-acid cytokine implicated with cartilage degradation, is secreted by vascular endothelial cells and also by many other cell types. The expression of ET-1 in human IVD cartilage endplate (CEP and its role in disc degeneration have not been explored. METHODS AND FINDINGS: The expression of ET-1 in degenerated CEP was analyzed by immunohistochemical staining and Western blotting; ET-1 was demonstrated in cartilaginous endplate cells (CECs by immunofluorescent staining. The ET-1 mRNA expression and protein production by CECs stimulated by tumor necrosis factor alpha (TNF-α, a pro-inflammatory cytokine, were determined by real-time PCR analysis and Western blotting, respectively. The matrix metalloprotease-1 (MMP-1, MMP-13 and tissue inhibitor of metalloproteases-1 (TIMP-1 levels in the supernatant of cultured CECs treated with ET-1 were determined using enzyme-linked immunosorbent assays. Nitric oxide (NO release and nitric oxide synthase (NOS activity were measured using a spectrophotometric assay. The apoptosis of CECs by ET-1 was measured by an Annexin V-FITC detection assay. The production of ET-1 in degenerated cartilage endplate was significantly higher than normal CEP. The results showed that ET-1 was expressed by CECs and modulated by TNF-α in a dose-dependent manner. ET-1 increased production of MMP-1 and MMP-13, decreased TIMP-1 production, and induced NO and NOS release by cultured CECs. The direct stimulation of CECs by ET-1 did not promote cell apoptosis. CONCLUSION: The study results suggest that ET-1 played a pivotal role in human CEP degeneration, and may be a new target for development of therapies for this condition.

Estrogen-induced improvement in coronary flow responses during atrial pacing in relation to endothelin-1 levels in postmenopausal women without coronary disease

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Ioannis Kallikazaros

2008-06-01

Full Text Available Ioannis Kallikazaros, Costas Tsioufis, Panagiotis Zambaras, Ioannis Skiadas, Marina Toutouza, Dimitrios Tousoulis, Christodoulos Stefanadis, Pavlos ToutouzasCardiology Department and University Cardiology Clinic, Hippokration Hospital of Athens, GreeceBackground: The cardioprotective role of hormonal replacement therapy remains in doubt, but interest is increasing in the vascular effects of estrogens especially in coronary circulation.Methods: Coronary blood flow (CBF was measured in 24 postmenopausal women (age 55 ± 3 years, whose coronary arteries appeared angiographically normal, during incremental atrial pacing (AP before and 20 minutes after intracoronary administration of either 75 ng/mL 17-β estradiol (treated group, n = 18 or 0.9% saline (controls, n = 6.Results: Before estrogen, no differences in the coronary vasomotor responses at AP between the two groups (p = NS could be detected. After estrogen, in the treated group, at the peak of the second AP, the coronary artery diameter decreased by 0.17 mm (p < 0.005 while the CBF increased by 61 mL/min (p < 0.05. These changes differed significantly from thoseobserved at the peak of first AP (p < 0.001 for both cases. In contrast, in the control group no such changes were observed. The endothelin-1 (ET-1 levels in the coronary sinus were significantly reduced after estrogen infusion, which was negatively correlated with the degree of coronary artery constriction (r = −0.40, p = 0.03 and positively correlated with the increase in CBF (r = 0.54, p = 0.01.Conclusions: In postmenopausal women without coronary artery disease, the intracoronary estrogen infusion mediates a greater increase in CBF and is positively correlated with the reduction of the coronary sinus ET-1 levels at the peak of AP.Keywords: estrogens, coronary blood flow, endothelin-1, coronary interventions

[Association between pulmonary vascular remodeling and expression of hypoxia-inducible factor-1α, endothelin-1 and inducible nitric oxide synthase in pulmonary vessels in neonatal rats with hypoxic pulmonary hypertension].

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Wang, Jian-Rong; Zhou, Ying; Sang, Kui; Li, Ming-Xia

2013-02-01

To investigate the association between pulmonary vascular remodeling and expression of hypoxia-inducible factor-1α (HIF-1α), endothelin-1 (ET-1) and inducible nitric oxide synthase (iNOS) in pulmonary vessels in neonatal rats with hypoxic pulmonary hypertension (HPH). A neonatal rat model of HPH was established as an HPH group, and normal neonatal rats were enrolled as a control group. The mean pulmonary arterial pressure (mPAP) was measured. The percentage of medial thickness to outer diameter of the small pulmonary arteries (MT%) and the percentage of medial cross-section area to total cross-section area of the pulmonary small arteries (MA%) were measured as the indicators for pulmonary vascular remodeling. The immunohistochemical reaction intensities for HIF-1α, ET-1 and iNOS and their mRNA expression in lung tissues of neonatal rats were measured. Correlation analysis was performed to determine the relationship between pulmonary vascular remodeling and mRNA expression of HIF-1α, ET-1 and iNOS. The mPAP of the HPH group kept increasing on days 3, 5, 7, 10, 14, and 21 of hypoxia, with a significant difference compared with the control group (P<0.05). The HPH group had significantly higher MT% and MA% than the control group from day 7 of hypoxia (P<0.05). HIF-1α protein expression increased significantly on days 3, 5, 7 and 10 days of hypoxia, and HIF-1α mRNA expression increased significantly on days 3, 5 and 7 days of hypoxia in the HPH group compared with the control group (P<0.05). ET-1 protein expression increased significantly on days 3, 5 and 7 days of hypoxia and ET-1 mRNA expression increased significantly on day 3 of hypoxia in the HPH group compared with the control group (P<0.05). Both iNOS protein and mRNA expression were significantly higher on days 3, 5 and 7 days of hypoxia than the control group (P<0.05). Both MT% and MA% were positively correlated with HIF-1α mRNA expression (r=0.835 and 0.850 respectively; P<0.05). Pulmonary vascular

Cerebrovascular endothelin receptor upregulation in cerebral ischemia

DEFF Research Database (Denmark)

Edvinsson, Lars

2009-01-01

Stroke is a serious neurological disease and the third leading cause of death in the western world. In roughly 15 % of the cases, the cause is due to an intracranial haemorrhage, and the remaining 85 % represent ischemic strokes. Ischemic stroke is caused by the occlusion of a cerebral artery...... either by an embolus or by local thrombosis. Several studies have shown an involvement of the endothelin system in ischemic stroke. This review aims to examine the alterations of vascular endothelin receptor expression in ischemic stroke. Furthermore, studies of the intracellular signalling pathways...... leading to the enhanced expression of vascular endothelin receptors show that both protein kinase C (PKC) and mitogen activating protein kinase (MAPK) play important roles. The results from this work provide new perspectives on the pathophysiology of ischemic stroke, and give a possible explanation...

PROLACTIN-INDUCED TYROSINE PHOSPHORYLATION, ACTIVATION AND RECEPTOR ASSOCIATION OF FOCAL ADHESION KINASE (FAK) IN MAMMARY EPITHELIAL CELLS

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Prolactin-Induced Tyrosine Phosphorylation, Activation and ReceptorAssociation of Focal Adhesion Kinase (FAK) in Mammary Epithelial Cells. Suzanne E. Fenton1 and Lewis G. Sheffield2. 1U.S. Environmental ProtectionAgency, MD-72, Research Triangle Park, NC 27711, and

Correlation of Endothelin-1 Concentration and Angiotensin-Converting Enzyme Activity with the Staging of Liver Fibrosis

OpenAIRE

Kardum, Duško; Fabijanić, Damir; Lukić, Anita; Romić, Željko; Petrovečki, Mladen; Bogdanović, Zoran; Jurić, Klara; Urek-Crnčević, Marija; Banić, Marko

2012-01-01

Increased serum angiotensin-converting enzyme (SACE) activity and serum concentration of endothelin-1 (ET-1) were found in liver cirrhosis. We investigated a correlation between the different stages of liver fibrosis and SACE activity and serum ET-1 concentration. Seventy patients with pathohistologically established chronic liver disease were divided in three groups according to Ishak criteria for liver fibrosis: minimal fibrosis (Ishak score 0–1, n=20), medium fibrosis (Ishak sc...

Different endothelin receptor affinities in dog tissues

International Nuclear Information System (INIS)

Loeffler, B.M.L.; Loehrer, W.

1991-01-01

Endothelin (ET) is a long-lasting potent vasoconstrictor-peptide. Here the authors report different binding affinities of endothelin-1 (ET-1) to ET-receptors of various dog tissues. Crude microsomal fractions were prepared after homogenisation of dog tissues in 50 mM Tris/HCl, 20 mM MnCl2, 1 mM EDTA, pH 7.4 by differential centrifugation. Aliquots of microsomal fractions (70 micrograms of protein) were incubated at 25 degrees C for 180 min in the presence of 20 pM 125I-ET-1 and various concentrations of cold ET-1. Four different ET-1 receptor binding affinities were found: adrenals, cerebrum, liver, heart, skeletal muscle and stomach microsomal membranes contained high affinity binding sites (Kd 50 - 80 pM, Bmax 60 - 250 fmol/mg). In cerebellum and spleen medium affinity ET-1 receptors (Kd 350 pM, Bmax 880 and 1200 fmol/mg respectively) were present. In comparison lung and kidney microsomes contained a low affinity ET-1 receptor (Kd 800 and 880 pM, Bmax 1600 and 350 fmol/mg). Receptors of even lower affinity were present in heart, intestine and liver microsomes with Kd values of 3 - 6 nM

Inhibiting focal adhesion kinase (FAK) blocks IL-4 induced VCAM-1 expression and eosinophil recruitment in vitro and in vivo.

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Aulakh, Gurpreet K; Petri, Björn; Wojcik, Katarzyna M; Colarusso, Pina; Lee, James J; Patel, Kamala D

2018-04-06

Leukocyte recruitment plays a critical role during both normal inflammation and chronic inflammatory diseases, and ongoing studies endeavor to better understand the complexities of this process. Focal adhesion kinase (FAK) is well known for its role in cancer, yet it also has been shown to regulate aspects of neutrophil and B16 melanoma cell recruitment by rapidly influencing endothelial cell focal adhesion dynamics and junctional opening. Recently, we found that FAK related non-kinase (FRNK), a protein that is often used as a FAK dominant negative, blocked eosinophil transmigration by preventing the transcription of vascular cell adhesion molecule-1 (VCAM-1) and eotaxin-3 (CCL26). Surprisingly, the blocking occurred even in the absence of endogenous FAK. To better understand the role of FAK in leukocyte recruitment, we used a FAK-specific inhibitor (PF-573228) and determined the effect on IL-4 induced eosinophil recruitment in vitro and in vivo. PF-573228 prevented the expression of VCAM-1 and CCL26 expression in IL-4-stimulated human endothelial cells in vitro. As a result, eosinophil adhesion and transmigration were blocked. PF-572338 also prevented IL-4-induced VCAM-1 expression in vivo. Using brightfield intravital microscopy, we found that PF-573228 decreased leukocyte rolling flux, adhesion, and emigration. We specifically examined eosinophil recruitment in vivo by using an eosinophil-GFP reporter mouse and found PF-573228 attenuated eosinophil emigration. This study reveals that a FAK inhibitor influences inflammation through its action on eosinophil recruitment. ©2018 Society for Leukocyte Biology.

Polyphenol fraction of extra virgin olive oil protects against endothelial dysfunction induced by high glucose and free fatty acids through modulation of nitric oxide and endothelin-1

OpenAIRE

Storniolo, Carolina Emilia; Roselló-Catafau, Joan; Pintó, Xavier; Mitjavila, María Teresa; Moreno, Juan José

2014-01-01

© 2014 The Authors. Epidemiological and clinical studies have reported that olive oil reduces the incidence of cardiovascular disease. However, the mechanisms involved in this beneficial effect have not been delineated. The endothelium plays an important role in blood pressure regulation through the release of potent vasodilator and vasoconstrictor agents such as nitric oxide (NO) and endothelin-1 (ET-1), respectively, events that are disrupted in type 2 diabetes. Extra virgin olive oil conta...

Investigation of role of plasma endothelin in diabetes mellitus patients complicated with angiocardiopathy

International Nuclear Information System (INIS)

Cong Jingbo; Wang Zhihua; Niu Aijun

2001-01-01

Objective: To study the role of plasma endothelin in diabetes mellitus (DM) patients complicated with angiocardiopathy. Methods: Plasma endothelin levels were determined by radioimmunoassay in 34 diabetics, 27 diabetics complicated with angiocardiopathy and in 30 controls. Results: Plasma endothelin levels in both diabetic groups were significantly higher than those in normal subjects (p < 0.01); plasma endothelin levels in DM patients complicated with angiocardiopathy were significantly higher than those in patients with diabetes only (p < 0.01). Conclusion: Plasma endothelin was of important role in the pathogenesis of DM complicated with angiocardiopathy and could be used as an early and sensitive marker

Involvement of endothelin and ET(A) endothelin receptor in mechanical allodynia in mice given orthotopic melanoma inoculation.

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Fujita, Masahide; Andoh, Tsugunobu; Saiki, Ikuo; Kuraishi, Yasushi

2008-02-01

We investigated whether endothelin (ET) would be involved in skin cancer pain in mice. Orthotopic inoculation of B16-BL6 melanoma cells into the plantar region of the hind paw produced marked mechanical allodynia in C57BL/6 mice. Intraplantar injections of the ET(A)-receptor antagonist BQ-123 (0.3 - 3 nmol/site), but not the ET(B)-receptor antagonist BQ-788 (1 and 3 nmol/site), inhibited mechanical allodynia in mice with grown melanoma. In naive mice, an intraplantar injection of tumor extract (1 and 3 mg/site), which was prepared from the grown melanoma in the paw, produced mechanical allodynia, which was inhibited by BQ-123 and BQ-788 at doses of 3 and 10 nmol/site. An intraplantar injection of ET-1 (1 and 10 pmol/site) elicited licking behavior, which was increased in the melanoma-bearing hind paw. BQ-123 (3 and 10 nmol/site) inhibited licking induced by ET-1 (10 pmol/site). The level of mRNA of ET(A), but not ET(B), receptor, was significantly increased in the dorsal root ganglia on the inoculated side. Cultured B16-BL6 cells contained ET, and the melanoma mass increased the concentration of ET as it grew bigger. These results suggest that ET-1 and ET(A) receptor are at least partly involved in the induction of pain induced by melanoma cell inoculation.

Pseudomonas-derived ceramidase induces production of inflammatory mediators from human keratinocytes via sphingosine-1-phosphate.

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Ami Oizumi

Full Text Available Ceramide is important for water retention and permeability barrier functions in the stratum corneum, and plays a key role in the pathogenesis of atopic dermatitis (AD. A Pseudomonas aeruginosa-derived neutral ceramidase (PaCDase isolated from a patient with AD was shown to effectively degrade ceramide in the presence of Staphylococcus aureus-derived lipids or neutral detergents. However, the effect of ceramide metabolites on the functions of differentiating keratinocytes is poorly understood. We found that the ceramide metabolite sphingosine-1-phosphate (S1P stimulated the production of inflammatory mediators such as TNF-α and IL-8 from three-dimensionally cultured human primary keratinocytes (termed "3D keratinocytes", which form a stratum corneum. PaCDase alone did not affect TNF-α gene expression in 3D keratinocytes. In the presence of the detergent Triton X-100, which damages stratum corneum structure, PaCDase, but not heat-inactivated PaCDase or PaCDase-inactive mutant, induced the production of TNF-α, endothelin-1, and IL-8, indicating that this production was dependent on ceramidase activity. Among various ceramide metabolites, sphingosine and S1P enhanced the gene expression of TNF-α, endothelin-1, and IL-8. The PaCDase-enhanced expression of these genes was inhibited by a sphingosine kinase inhibitor and by an S1P receptor antagonist VPC 23019. The TNF-α-binding antibody infliximab suppressed the PaCDase-induced upregulation of IL-8, but not TNF-α, mRNA. PaCDase induced NF-κB p65 phosphorylation. The NF-κB inhibitor curcumin significantly inhibited PaCDase-induced expression of IL-8 and endothelin-1. VPC 23019 and infliximab inhibited PaCDase-induced NF-κB p65 phosphorylation and reduction in the protein level of the NF-κB inhibitor IκBα. Collectively, these findings suggest that (i 3D keratinocytes produce S1P from sphingosine, which is produced through the hydrolysis of ceramide by PaCDase, (ii S1P induces the production

Induction of interleukin-1β mRNA after focal cerebral ischaemia in the rat

NARCIS (Netherlands)

Buttini, M.; Sauter, A.; Boddeke, H.W.G.M.

1994-01-01

The expression of interleukin-1β (IL-1β) mRNA in the brain in response to cerebral ischaemia in rats was examined using in situ hybridization histochemistry. Focal cerebral ischaemia was induced in spontaneously hypertensive rats by permanent occlusion of the left middle cerebral artery (MCAO).

INDUCTION OF INTERLEUKIN-1-BETA MESSENGER-RNA AFTER FOCAL CEREBRAL-ISCHEMIA IN THE RAT

NARCIS (Netherlands)

BUTTINI, M; SAUTER, A; BODDEKE, HWGM

The expression of interleukin-1beta (IL-1beta) mRNA in the brain in response to cerebral ischaemia in rats was examined using in situ hybridization histochemistry. Focal cerebral ischaemia was induced in spontaneously hypertensive rats by permanent occlusion of the left middle cerebral artery

Endothelins in chronic liver disease

DEFF Research Database (Denmark)

Møller, Søren; Henriksen, Jens Henrik

1996-01-01

This review describes recent progress in the accumulation of knowledge about the endothelins (ETs), a family of vasoactive 21-amino acid polypeptides, in chronic liver disease. Particular prominence is given to the dynamics of ET-1 and ET-3 and their possible relation to the disturbed circulation...... renal failure. Studies on liver biopsies have revealed synthesis of ET-1 in hepatic endothelial and other cells, and recent investigations have identified the hepatosplanchnic system as a major source of ET-1 and ET-3 spillover into the circulation, with a direct relation to portal venous hypertension...

Increasing plasma fibrinogen, but unchanged levels of intraplatelet cyclic nucleotides, plasma endothelin-1, factor VII, and neopterin during cholesterol lowering with fluvastatin.

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Gottsäter, A; Anwaar, I; Lind, P; Mattiasson, I; Lindgärde, F

1999-04-01

Lipid-lowering statin treatment reduces cardiovascular morbidity and mortality and improves endothelial function in patients with hypercholesterolemia. The aim of the present study was to evaluate plasma levels of fibrinogen, factor VII, and the macrophage-derived inflammatory mediator neopterin during lipid lowering. In addition, the endothelial production of platelet antiaggregatory and vasodilatory factors such as nitric oxide and prostacyclin, and vasoconstrictive factors such as endothelin-1, was assessed. Plasma fibrinogen, factor VII, endothelin-1, and the neopterin and intraplatelet nitric oxide and prostacyclin mediators cyclic 3'-5'guanosine monophosphate (cGMP) and cyclic 3'-5'adenosine monophosphate (cAMP) were measured before and 6 months after the institution of treatment with fluvastatin in 17 patients (eight men and nine women, median age 60 years) with vascular disease and previously untreated hypercholesterolemia. After 6 months, a decrease of 1.62 mmol/l [1.26-2.18 (19%); P factor VII [from 1.14 IE/ml (0.58-1.38) to 1.22 IE/ml (0.96-1.46); NS], or plasma neopterin [from 8.6 nmol/l (7.1-11.5) to 8.7 nmol/l (7.9-11.3); NS]. In conclusion, during cholesterol-lowering treatment with fluvastatin, plasma levels of fibrinogen increased whereas intraplatelet cyclic nucleotide levels and plasma endothelin-1, factor VII and neopterin levels were unchanged.

Determination of adrenomedullin and endothelin in cord blood and their expressions in umbilical cord vessel of patients with pregnancy-induced hypertension

International Nuclear Information System (INIS)

Ruan Lihong; Zhu Fengquan; Wang Xing; Pan Yu

2004-01-01

Objective: To investigate the role of adrenomedullin (ADM) and endothelin-1 (ET-1) in the pathogenesis of pregnancy-induced hypertension (PIH). Methods: The plasma concentrations of ADM in human umbilical vein of PIH patients (n=30) and normal late trimester pregnancy women (n=12) were measured by radioimmunoassay. The expressions of ADM and ET-1 in umbilical cord vessel of PIH patients (n=40) and normal late trimester pregnancy women (n=12) were detected by immunohistochemistry (SABC). Results: 1) The plasma concentration of ADM in human umbilical vein of PIH patients was significantly higher than that of normal late trimester pregnancy women (P 0.05). 2) The expression of ADM was found in endothelium and smooth muscle cell of umbilical cord vessel, and it increased with the serious degree of PIH. The expression of ET-1 was only found in endothelium of umbilical cord vessel, and it decreased with the serious degree of PIH. Conclusion: The changes of ADM and ET-1 in umbilical cord plasma and vessel may related to regulation of fetoplacental circulation in PIH

Lactate, endothelin, and central venous oxygen saturation as predictors of mortality in patients with Tetralogy of Fallot

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Poonam Malhotra Kapoor

2016-01-01

Full Text Available Background: Lactate and central venous oxygen saturation (ScVO2 are well known biomarkers for adequacy of tissue oxygenation. Endothelin, an inflammatory marker has been associated with patient′s nutritional status and degree of cyanosis. The aim of this study was to explore the hypothesis that lactate, ScVO2 and endothelin before induction may be predictive of mortality in pediatric cardiac surgery. Methods: We conducted a prospective observational study of 150 pediatric (6 months to 12 years patients who were posted for intracardiac repair for tetralogy of fallot and measured lactate, ScVO2 and endothelin before induction (T1, 20 minutes after protamine administration (T2 and 24 hours after admission to ICU (T3. Results: Preinduction lactate and endothelin levels were found to predict mortality in patients of tetralogy of fallot with an odds ratio of 6.020 (95% CI 2.111-17.168 and 1.292(95% CI 1.091-1.531 respectively. In the ROC curve analysis for lactate at T1, the AUC was 0.713 (95% CI 0.526-0.899 P = 0.019. At the cutoff value of 1.750mmol/lt, the sensitivity and specificity for the prediction of mortality was 63.6% and 65.5%, respectively. For endothelin at T1, the AUC was 0.699 (95% CI 0.516-0.883, P = 0.028 and the cutoff value was ≤2.50 (sensitivity, 63.6%; specificity, 58.3 %. ScVO2 (odds ratio 0.85 at all three time intervals, suggested that improving ScVO2 can lead to 15% reduction in mortality. Conclusions: Lactate, ScVO2 and endothelin all showed association with mortality with lactate having the maximum prediction. Lactate was found to be an independent, reliable and cost-effective measure of prediction of mortality in patients with tetralogy of fallot.

Polymorphisms in nitric oxide synthase and endothelin genes among children with obstructive sleep apnea.

Science.gov (United States)

Chatsuriyawong, Siriporn; Gozal, David; Kheirandish-Gozal, Leila; Bhattacharjee, Rakesh; Khalyfa, Ahamed A; Wang, Yang; Sukhumsirichart, Wasana; Khalyfa, Abdelnaby

2013-09-06

Obstructive sleep apnea (OSA) is associated with adverse and interdependent cognitive and cardiovascular consequences. Increasing evidence suggests that nitric oxide synthase (NOS) and endothelin family (EDN) genes underlie mechanistic aspects of OSA-associated morbidities. We aimed to identify single nucleotide polymorphisms (SNPs) in the NOS family (3 isoforms), and EDN family (3 isoforms) to identify potential associations of these SNPs in children with OSA. A pediatric community cohort (ages 5-10 years) enriched for snoring underwent overnight polysomnographic (NPSG) and a fasting morning blood draw. The diagnostic criteria for OSA were an obstructive apnea-hypopnea Index (AHI) >2/h total sleep time (TST), snoring during the night, and a nadir oxyhemoglobin saturation DNA from peripheral blood was extracted and allelic frequencies were assessed for, NOS1 (209 SNPs), NOS2 (122 SNPs), NOS3 (50 SNPs), EDN1 (43 SNPs), EDN2 (48 SNPs), EDN3 (14 SNPs), endothelin receptor A, EDNRA, (27 SNPs), and endothelin receptor B, EDNRB (23 SNPs) using a custom SNPs array. The relative frequencies of NOS-1,-2, and -3, and EDN-1,-2,-3,-EDNRA, and-EDNRB genotypes were evaluated in 608 subjects [128 with OSA, and 480 without OSA (NOSA)]. Furthermore, subjects with OSA were divided into 2 subgroups: OSA with normal endothelial function (OSA-NEF), and OSA with endothelial dysfunction (OSA-ED). Linkage disequilibrium was analyzed using Haploview version 4.2 software. For NOSA vs. OSA groups, 15 differentially distributed SNPs for NOS1 gene, and 1 SNP for NOS3 emerged, while 4 SNPs for EDN1 and 1 SNP for both EDN2 and EDN3 were identified. However, in the smaller sub-group for whom endothelial function was available, none of the significant SNPs was retained due to lack of statistical power. Differences in the distribution of polymorphisms among NOS and EDN gene families suggest that these SNPs could play a contributory role in the pathophysiology and risk of OSA-induced cardiovascular

Endothelin-1 promotes epithelial–mesenchymal transition in human chondrosarcoma cells by repressing miR-300

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Wu, Min-Huan; Huang, Pei-Han; Hsieh, Mingli; Tsai, Chun-Hao; Chen, Hsien-Te; Tang, Chih-Hsin

2016-01-01

Chondrosarcoma is a malignant tumor of mesenchymal origin predominantly composed of cartilage-producing cells. This type of bone cancer is extremely resistant to radiotherapy and chemotherapy. Surgical resection is the primary treatment, but is often difficult and not always practical for metastatic disease, so more effective treatments are needed. In particular, it would be helpful to identify molecular markers as targets for therapeutic intervention. Endothelin-1 (ET-1), a potent vasoconstrictor, has been shown to enhance chondrosarcoma angiogenesis and metastasis. We report that ET-1 promotes epithelial–mesenchymal transition (EMT) in human chondrosarcoma cells. EMT is a key pathological event in cancer progression, during which epithelial cells lose their junctions and apical-basal polarity and adopt an invasive phenotype. Our study verifies that ET-1 induces the EMT phenotype in chondrosarcoma cells via the AMP-activated protein kinase (AMPK) pathway. In addition, we show that ET-1 increases EMT by repressing miR-300, which plays an important role in EMT-enhanced tumor metastasis. We also show that miR-300 directly targets Twist, which in turn results in a negative regulation of EMT. We found a highly positive correlation between ET-1 and Twist expression levels as well as tumor stage in chondrosarcoma patient specimens. Therefore, ET-1 may represent a potential novel molecular therapeutic target in chondrosarcoma metastasis. PMID:27602960

Endothelin-1 promotes epithelial-mesenchymal transition in human chondrosarcoma cells by repressing miR-300.

Science.gov (United States)

Wu, Min-Huan; Huang, Pei-Han; Hsieh, Mingli; Tsai, Chun-Hao; Chen, Hsien-Te; Tang, Chih-Hsin

2016-10-25

Chondrosarcoma is a malignant tumor of mesenchymal origin predominantly composed of cartilage-producing cells. This type of bone cancer is extremely resistant to radiotherapy and chemotherapy. Surgical resection is the primary treatment, but is often difficult and not always practical for metastatic disease, so more effective treatments are needed. In particular, it would be helpful to identify molecular markers as targets for therapeutic intervention. Endothelin-1 (ET-1), a potent vasoconstrictor, has been shown to enhance chondrosarcoma angiogenesis and metastasis. We report that ET-1 promotes epithelial-mesenchymal transition (EMT) in human chondrosarcoma cells. EMT is a key pathological event in cancer progression, during which epithelial cells lose their junctions and apical-basal polarity and adopt an invasive phenotype. Our study verifies that ET-1 induces the EMT phenotype in chondrosarcoma cells via the AMP-activated protein kinase (AMPK) pathway. In addition, we show that ET-1 increases EMT by repressing miR-300, which plays an important role in EMT-enhanced tumor metastasis. We also show that miR-300 directly targets Twist, which in turn results in a negative regulation of EMT. We found a highly positive correlation between ET-1 and Twist expression levels as well as tumor stage in chondrosarcoma patient specimens. Therefore, ET-1 may represent a potential novel molecular therapeutic target in chondrosarcoma metastasis.

G-231A and G+70C polymorphisms of endothelin receptor type-A gene could affect the psoriasis area and severity index score and endothelin 1 levels

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Gökhan Okan

2015-01-01

Full Text Available Background: The etiopathogenesis of psoriasis has not been clearly elucidated although the role of chronic inflammation, imbalance between pro- and anti-inflammatory cytokines, and many immunological events have been established. Endothelin 1 (EDN1 and endothelin receptor type-A (EDNRA are implicated in the inflammatory process. The relationships between EDN1 and EDNRA polymorphisms with several diseases have been found. Aims and Objectives: This study examined the possible association of EDN1 (G5665T and T-1370G and EDNRA (G-231A and G + 70C single nucleotide polymorphisms (SNPs with the occurence of psoriasis, and evaluated the relationship between genotypes and clinical/laboratory manifestation of psoriasis. Materials and Methods: We analyzed genotype and allele distributions of the above-mentioned polymorphisms in 151 patients with psoriasis and 152 healthy controls by real-time PCR combined with melting curve analysis. Results: We did not find significant differences in the genotype and allele distributions of EDN1 T-1370G, EDNRA G-231A, and EDNRA G+70C polymorphisms between patients with psoriasis and healthy controls. Psoriasis area and severity index (PASI score of EDNRA -231 polymorphic A allele carrying subjects (AA and AA + AG was higher than that of wild homozygotes (P = 0.044 and P = 0.027, respectively. In addition, EDN1 levels in EDNRA+70 polymorphic C allele carriers (CC + CG were elevated when compared with GG genotype; however, the difference was at borderline significance (P = 0.05. Conclusion: Although there were no associations between studied polymorphisms and psoriasis susceptibility, the PASI score and EDN1 levels seem to be affected by EDNRA G-231A and G + 70C polymorphisms.

Argirein alleviates stress-induced and diabetic hypogonadism in rats via normalizing testis endothelin receptor A and connexin 43.

Science.gov (United States)

Xu, Ming; Hu, Chen; Khan, Hussein-hamed; Shi, Fang-hong; Cong, Xiao-dong; Li, Qing; Dai, Yin; Dai, De-zai

2016-02-01

Argirein (rhein-arginine) is a derivative of rhein isolated from Chinese rhubarb (Rheum Officinale Baill.) that exhibits antioxidant and anti-inflammatory activities. In the present study we investigated the effects of argirein on stress-induced (hypergonadotrophic) and diabetic (hypogonadotrophic) hypogonadism in male rats. Stress-induced and diabetic hypogonadism was induced in male rats via injection of isoproterenol (ISO) or streptozotocin (STZ). ISO-injected rats were treated with argirein (30 mg·kg(-1)·d(-1), po) or testosterone replacement (0.5 mg·kg(-1)·d(-1), sc) for 5 days, and STZ-injected rats were treated with argirein (40-120 mg·kg(-1)·d(-1), po) or aminoguanidine (100 mg·kg(-1)·d(-1), po) for 4 weeks. After the rats were euthanized, blood samples and testes were collected. Serum hormone levels were measured, and the expression of endothelin receptor A (ETA), connexin 43 (Cx43) and other proteins in testes was detected. For in vitro experiments, testis homogenate was prepared from normal male rats, and incubated with ISO (1 μmol/L) or high glucose (27 mmol/L). ISO injection induced hyper-gonadotrophic hypogonadism characterized by low testosterone and high FSH and LH levels in the serum, whereas STZ injection induced hypogonadotrophic hypogonadism as evidenced by low testosterone and low FSH and LH levels in the serum. In the testes of ISO- and STZ-injected rats, the expression of ETA, MMP-9, NADPH oxidase and pPKCε was significantly increased, and the expression of Cx43 was decreased. Administration of argirein attenuated both the abnormal serum hormone levels and the testis changes in ISO- and STZ-injected rats, and aminoguanidine produced similar actions in STZ-injected rats; testosterone replacement reversed the abnormal serum hormone levels, but did not affect the testis changes in ISO-injected rats. Argirein (0.3-3 μmol/L) exerted similar effects in testis homogenate incubated with ISO or high glucose in vitro. Two types of

Progestins oppose the effects of estradiol on the endothelin-1 receptor type B in coronary arteries from ovariectomized hyperlipidemic rabbits

DEFF Research Database (Denmark)

Pedersen, Susan H; Nielsen, Lars B; Mortensen, Alicja

2008-01-01

OBJECTIVE: Progestins may be associated with the adverse cardiovascular outcomes observed with estrogen plus progestogen therapy, but the mechanism is not resolved. In this study we examined the effect of 17beta-estradiol (E2) alone and in combination with two progestins on the endothelin-1 (ET-1...

Over, and Underexpression of Endothelin 1 and TGF-Beta Family Ligands and Receptors in Lung Tissue of Broilers with Pulmonary Hypertension

Science.gov (United States)

Dominguez-Avila, Norma; Ruiz-Castañeda, Gabriel; González-Ramírez, Javier; Fernandez-Jaramillo, Nora; Escoto, Jorge; Sánchez-Muñoz, Fausto; Marquez-Velasco, Ricardo; Bojalil, Rafael; Espinosa-Cervantes, Román; Sánchez, Fausto

2013-01-01

Transforming growth factor beta (TGFβ) is a family of genes that play a key role in mediating tissue remodeling in various forms of acute and chronic lung disease. In order to assess their role on pulmonary hypertension in broilers, we determined mRNA expression of genes of the TGFβ family and endothelin 1 in lung samples from 4-week-old chickens raised either under normal or cold temperature conditions. Both in control and cold-treated groups of broilers, endothelin 1 mRNA expression levels in lungs from ascitic chickens were higher than levels from healthy birds (P 0.05). BAMBI mRNA gene expression was lowest in birds with ascites only in the control group as compared with the values from healthy birds (P < 0.05). PMID:24286074

Anti-hypotensive treatment and endothelin blockade synergistically antagonize exercise fatigue in rats under simulated high altitude.

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Daniel Radiloff

Full Text Available Rapid ascent to high altitude causes illness and fatigue, and there is a demand for effective acute treatments to alleviate such effects. We hypothesized that increased oxygen delivery to the tissue using a combination of a hypertensive agent and an endothelin receptor A antagonist drugs would limit exercise-induced fatigue at simulated high altitude. Our data showed that the combination of 0.1 mg/kg ambrisentan with either 20 mg/kg ephedrine or 10 mg/kg methylphenidate significantly improved exercise duration in rats at simulated altitude of 4,267 m, whereas the individual compounds did not. In normoxic, anesthetized rats, ephedrine alone and in combination with ambrisentan increased heart rate, peripheral blood flow, carotid and pulmonary arterial pressures, breathing rate, and vastus lateralis muscle oxygenation, but under inspired hypoxia, only the combination treatment significantly enhanced muscle oxygenation. Our results suggest that sympathomimetic agents combined with endothelin-A receptor blockers offset altitude-induced fatigue in rats by synergistically increasing the delivery rate of oxygen to hypoxic muscle by concomitantly augmenting perfusion pressure and improving capillary conductance in the skeletal muscle. Our findings might therefore serve as a basis to develop an effective treatment to prevent high-altitude illness and fatigue in humans.

Metallothionein-1+2 protect the CNS after a focal brain injury

DEFF Research Database (Denmark)

Giralt, Mercedes; Penkowa, Milena; Lago, Natalia

2002-01-01

We have evaluated the physiological relevance of metallothionein-1+2 (MT-1+2) in the CNS following damage caused by a focal cryolesion onto the cortex. In comparison to normal mice, transgenic mice overexpressing the MT-1 isoform (TgMTI* mice) showed a significant decrease of the number...... dramatically reduced the cryolesion-induced oxidative stress and neuronal apoptosis. Remarkably, these effects were also obtained by the intraperitoneal administration of MT-2 to both normal and MT-1+2 knock-out mice. These results fully support the notion that MT-1+2 are essential in the CNS for coping...

Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognition in urban children.

Science.gov (United States)

Calderón-Garcidueñas, Lilian; Mora-Tiscareño, Antonieta; Franco-Lira, Maricela; Cross, Janet V; Engle, Randall; Aragón-Flores, Mariana; Gómez-Garza, Gilberto; Jewells, Valerie; Medina-Cortina, Humberto; Solorio, Edelmira; Chao, Chih-Kai; Zhu, Hongtu; Mukherjee, Partha S; Ferreira-Azevedo, Lara; Torres-Jardón, Ricardo; D'Angiulli, Amedeo

2013-01-01

Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA) children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children). We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1) and/or inflammatory mediators in MCMA children. Thirty gram of dark cocoa with 680 mg of total flavonols were given daily for 10.11 ± 3.4 days (range 9-24 days) to 18 children (10.55 years, SD = 1.45; 11F/7M). Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p = 0.0002). Fifteen children (83%) showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter (PM) and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer's and Parkinson's diseases.

Up-Regulation of Endothelin Type A Receptor in Human and Rat Radiation Proctitis: Preclinical Therapeutic Approach With Endothelin Receptor Blockade

International Nuclear Information System (INIS)

Jullien, Nicolash; Blirando, Karl; Milliat, Fabien; Sabourin, Jean-Christophe; Benderitter, Marc; Francois, Agnes

2009-01-01

Purpose: Rectum radiation damage and fibrosis are often associated with radiation therapy of pelvic tumors. The endothelin (ET) system has been implicated in several fibrotic diseases but never studied in the context of gastrointestinal radiation damage. This study assessed modifications in ET type 1 (ET-1), ET type A receptor (ET A ), and ET type B receptor (ET B ) localization and/or expression in irradiated human rectal tissue and in a rat model of delayed colorectal injury. We also evaluated the therapeutic potential of long-term ET receptor blockade. Methods and Materials: Routine histological studies of sections of healthy and radiation-injured human rectum tissue were done; the sections were also immunostained for ET A and ET B receptors. The rat model involved the delivery of 27 Gy in a single dose to the colons and rectums of the animals. The ET-1/ET A /ET B expression and ET A /ET B localization were studied at 10 weeks postexposure. The abilities of bosentan and atrasentan to protect against delayed rectal injury were also investigated. Results: The immunolocalization of ET A and ET B in healthy human rectums was similar to that in rat rectums. However, strong ET A immunostaining was seen in the presence of human radiation proctitis, and increased ET A mRNA levels were seen in the rat following colorectal irradiation. Immunostaining for ET A was also strongly positive in rats in areas of radiation-induced mucosal ulceration, atypia, and fibroproliferation. However, neither bosentan nor atrasentan prevented radiation damage to the rectum when given long term. The only effect seen for atrasentan was an increased number of sclerotic vessel sections in injured tissues. Conclusions: As the result of the overexpression of ET A , radiation exposure deregulates the endothelin system through an 'ET A profile' in the human and rodent rectum. However, therapeutic interventions involving mixed or specific ET A receptor blockade do not prevent radiation damage

The Role of Phosphoramidon on the Biological Activity of Big Endothelin-1 in the Rat Mesenteric Microcirculation in Vivo

International Nuclear Information System (INIS)

Abdelhalim, Mohamed A K

2008-01-01

The goal of the present study was to clarify the role of metalloprotease inhibitor phosphoramidon on the effects induced by big endothelin-1 (big ET-1) in the rat mesenteric microcirculation in vivo, through investigating the systemic blood pressure, diameter and blood flow velocity of arterioles and venules of the rat mesentery. For this purpose, the rat mesentery was arranged for in situ intravital microscopic observation under transillumination and separate cumulative injections of big ET-1 and phosphoramidon were infused into the right jugular vein, respectively. In these experiments twenty-five rats (Charles River, 130 - 140 g) were used. The experiments were divided into two groups. In the first group of experiments, cumulative injections of big ET-1 (1000-8000 pmole/kg) were infused through a catheter inserted into the right jugular vein. Each dose of big ET-1 was infused 25 min prior to the infusion of the following dose. Infusion of big ET-1 (1000-8000 pmole/kg) elicited a long-lasting pressor effect. The infusion of low doses of big ET-1 (1000-2000 pmole/kg) elicited a significant (p < 0.05) dose-dependent increase in the microvascular blood flow velocity both in arterioles (20 - 30 ?m) and venules (30 - 50 ?m), and diameters of arterioles and venules exhibited a slight not significant vasodilator effect. The infusion of high doses of big ET-1 (4000-8000 pmole/kg) elicited significant dose-dependant decrease in the blood flow velocity of arterioles and venules, and diameters returned to the control runs. This may be attributed to the gradual conversion of big ET-1 to ET-1, and ET-1 is a potent vasoconstrictor. In the second group of experiments, cumulative injections of phosphoramidon (30 mg/kg /10 min) were administered 10 min prior to the infusion of big ET-1. These findings suggested that phosphoramidon significantly suppressed long-lasting pressor effect, dose-dependent increase, dose-dependent decrease and slow vasodilator effect produced by big ET-1

Effects of age and caloric restriction in the vascular response of renal arteries to endothelin-1 in rats.

Science.gov (United States)

Amor, Sara; García-Villalón, Angel Luis; Rubio, Carmen; Carrascosa, Jose Ma; Monge, Luis; Fernández, Nuria; Martín-Carro, Beatriz; Granado, Miriam

2017-02-01

Cardiovascular alterations are the most prevalent cause of impaired physiological function in aged individuals with kidney being one the most affected organs. Aging-induced alterations in renal circulation are associated with a decrease in endothelium-derived relaxing factors such as nitric oxide (NO) and with an increase in contracting factors such as endothelin-1(ET-1). As caloric restriction (CR) exerts beneficial effects preventing some of the aging-induced alterations in cardiovascular system, the aim of this study was to analyze the effects of age and caloric restriction in the vascular response of renal arteries to ET-1 in aged rats. Vascular function was studied in renal arteries from 3-month-old Wistar rats fed ad libitum (3m) and in renal arteries from 8-and 24-month-old Wistar rats fed ad libitum (8m and 24m), or subjected to 20% caloric restriction during their three last months of life (8m-CR and 24m-CR). The contractile response to ET-1 was increased in renal arteries from 8m and 24m compared to 3m rats. ET-1-induced contraction was mediated by ET-A receptors in all experimental groups and also by ET-B receptors in 24m rats. Caloric restriction attenuated the increased contraction to ET-1 in renal arteries from 8m but not from 24m rats possibly through NO release proceeding from ET-B endothelial receptors. In 24m rats, CR did not attenuate the aging-increased response of renal arteries to ET-1, but it prevented the aging-induced increase in iNOS mRNA levels and the aging-induced decrease in eNOS mRNA levels in arterial tissue. In conclusion, aging is associated with an increased response to ET-1 in renal arteries that is prevented by CR in 8m but not in 24m rats. Copyright © 2016 Elsevier Inc. All rights reserved.

The role of the biomarker and the genetic polymorphism of endothelin-1 in pulmonary arterial hypertension among Egyptians

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Emad Ibrahim

2012-10-01

Conclusions: In conclusion, our findings suggest a potential link between endothelin-1 level and specific genotypes in the EDN1 gene and susceptibility for PAH with a worse haemodynamic profile. Further investigations are warranted to understand the molecular basis and to confirm the potential clinical importance of these findings on larger cohorts of patients with PAH. This will impact on the management of PAH of Egyptian patients in the near future.

Sandwich-type enzyme immunoassay for big endothelin-I in plasma: concentrations in healthy human subjects unaffected by sex or posture.

Science.gov (United States)

Aubin, P; Le Brun, G; Moldovan, F; Villette, J M; Créminon, C; Dumas, J; Homyrda, L; Soliman, H; Azizi, M; Fiet, J

1997-01-01

A sandwich-type enzyme immunoassay has been developed for measuring human big endothelin-1 (big ET-1) in human plasma and supernatant fluids from human cell cultures. Big ET-1 is the precursor of endothelin 1 (ET-1), the most potent vasoconstrictor known. A rabbit antibody raised against the big ET-1 COOH-terminus fragment was used as an immobilized antibody (anti-P16). The Fab' fragment of a monoclonal antibody (1B3) raised against the ET-1 loop fragment was used as the enzyme-labeled antibody, after being coupled to acetylcholinesterase. The lowest detectable value in the assay was 1.2 pg/mL (0.12 pg/well). The assay was highly specific for big ET-1, demonstrating no cross-reactivity with ET-1, big endothelin-2 (big ET-2), and big endothelin-3 (big ET-3). We used this assay to evaluate the effect of two different postural positions (supine and standing) on plasma big ET-1 concentrations in 11 male and 11 female healthy subjects. Data analysis revealed that neither sex nor body position influenced plasma big ET-1 concentrations. This assay should thus permit the detection of possible variations in plasma concentrations of big ET-1 in certain pathologies and, in association with ET-1 assay, make possible in vitro study of endothelin-converting enzyme activity in cell models. Such studies could clarify the physiological and clinical roles of this family of peptides.

Orphan Nuclear Receptor Nur77 Is a Novel Negative Regulator of Endothelin-1 Expression In Vascular Endothelial Cells

OpenAIRE

Qin, Qing; Chen, Ming; Yi, Bing; You, Xiaohua; Yang, Ping; Sun, Jianxin

2014-01-01

Endothelin-1 (ET-1) produced by vascular endothelial cells plays essential roles in the regulation of vascular tone and development of cardiovascular diseases. The objective of this study is to identify novel regulators implicated in the regulation of ET-1 expression in vascular endothelial cells (ECs). By using quantitative real-time PCR (qRT-PCR) and Enzyme-linked immunosorbent assay (ELISA), we show that either ectopic expression of orphan nuclear receptor Nur77 or pharmacological activati...

Plasmatic endothelin-1 levels in hyperthyroid patients before and after antithyroid therapy.

Science.gov (United States)

Cesareo, R; Tarabuso, A; Di Benedetto, M; Lacerna, F; Reda, G

2000-03-01

The Endothelin-1 (ET-1) is a powerful vasoconstrictor peptide produced by endothelial cells in many vascular diseases probably as a response to vessel damage. In hyperthyroidism as in other endocrinological diseases elevated ET-1 plasma levels have been found. The effect of antithyroid therapy on ET-1 plasmatic levels was evaluated by measuring ET-1 plasma levels before and 2 and 6 months after treatment with methimazole in 14 patients affected by hyperthyroidism. The hyperthyroid patients had significantly higher ET-1 levels than the controls (18.85 +/- 5.7 vs 10.9 +/- 2.1 pg/ml), while after treatment no difference was found. The ET-1 plasma levels of hyperthyroid patients correlated closely with the raised thyroid metabolic activity independently of its cause. It is possible that the increased ET-1 levels in hyperthyroid patients are the expression of blood vessel damage caused by high thyroid hormone levels. Moreover the results of this study could suggest that, in future, ET-1 plasmatic levels might be considered as a functional thyroid index in hyperthyroid diseases.

The endothelin system has a significant role in the pathogenesis and progression of Mycobacterium tuberculosis infection.

Science.gov (United States)

Correa, Andre F; Bailão, Alexandre M; Bastos, Izabela M D; Orme, Ian M; Soares, Célia M A; Kipnis, Andre; Santana, Jaime M; Junqueira-Kipnis, Ana Paula

2014-12-01

Tuberculosis (TB) remains a major global health problem, and although multiple studies have addressed the relationship between Mycobacterium tuberculosis and the host on an immunological level, few studies have addressed the impact of host physiological responses. Proteases produced by bacteria have been associated with important alterations in the host tissues, and a limited number of these enzymes have been characterized in mycobacterial species. M. tuberculosis produces a protease called Zmp1, which appears to be associated with virulence and has a putative action as an endothelin-converting enzyme. Endothelins are a family of vasoactive peptides, of which 3 distinct isoforms exist, and endothelin 1 (ET-1) is the most abundant and the best-characterized isoform. The aim of this work was to characterize the Zmp1 protease and evaluate its role in pathogenicity. Here, we have shown that M. tuberculosis produces and secretes an enzyme with ET-1 cleavage activity. These data demonstrate a possible role of Zmp1 for mycobacterium-host interactions and highlights its potential as a drug target. Moreover, the results suggest that endothelin pathways have a role in the pathogenesis of M. tuberculosis infections, and ETA or ETB receptor signaling can modulate the host response to the infection. We hypothesize that a balance between Zmp1 control of ET-1 levels and ETA/ETB signaling can allow M. tuberculosis adaptation and survival in the lung tissues. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

The Matrix Metalloproteases and Endothelin-1 in Infection-Associated Preterm Birth

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Nicole S. Olgun

2010-01-01

Full Text Available Preterm birth (PTB is clinically defined as any delivery which occurs before the completion of 37 weeks of gestation, and is currently the most important problem in obstetrics. In the United States, PTB accounts for 12-13% of all live births, and, with the exception of fetuses suffering from anomalies, is the primary cause of perinatal mortality. While the risk factors for PTB are numerous, the single most common cause is intrauterine infection. As there is currently no FDA-approved therapy for infection-associated PTB, understanding the pathogenesis of preterm labor (PTL and delivery should be given high priority. The matrix metalloproteinases (MMPs are a family of enzymes that have been implicated in normal parturition as well as infection-triggered rupture of membranes and preterm birth. Several lines of evidence also suggest a role for endothelin-1 (ET-1 in infection-associated preterm delivery. This paper focuses on the evidence that the MMPs and ET-1 act in the same molecular pathway in preterm birth.

Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognitive responses in urban children.

Directory of Open Access Journals (Sweden)

Lilian eCalderon-Garciduenas

2013-08-01

Full Text Available Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children. We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1 and/or inflammatory mediators in MCMA children. Thirty g of dark cocoa with 680 mg of total flavonols were given daily for 10.11± 3.4 days (range 9 to 24 days to 18 children (10.55yrs, SD =1.45; 11F/7M. Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p=0.0002. Fifteen children (83% showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer’s and Parkinson’s diseases.

Effect of breed on plasma endothelin-1 concentration, plasma renin activity, and serum cortisol concentration in healthy dogs

DEFF Research Database (Denmark)

Höglund, K.; Lequarré, A.-S.; Ljungvall, I.

2016-01-01

BACKGROUND: There are breed differences in several blood variables in healthy dogs. OBJECTIVE: Investigate breed variation in plasma endothelin-1 (ET-1) concentration, plasma renin activity, and serum cortisol concentration. ANIMALS: Five-hundred and thirty-one healthy dogs of 9 breeds examined...... at 5 centers (2-4 breeds/center). METHODS: Prospective observational study. Circulating concentrations of ET-1 and cortisol, and renin activity, were measured using commercially available assays. Absence of organ-related or systemic disease was ensured by thorough clinical investigations, including...

L-arginine does not prevent the renal effects of endothelin in humans

NARCIS (Netherlands)

Bijlsma, J. A.; Rabelink, A. J.; Kaasjager, K. A.; Koomans, H. A.

1995-01-01

The infusion of endothelin to obtain plasma levels as present in sodium-retaining conditions such as heart failure and hepatorenal syndrome has been shown to cause sodium retention and renal vasoconstriction. Whether these renal effects of endothelin could be modulated by the stimulation of nitric

Delayed brain ischemia tolerance induced by electroacupuncture pretreatment is mediated via MCP-induced protein 1

Science.gov (United States)

2013-01-01

Background Emerging studies have demonstrated that pretreatment with electroacupuncture (EA) induces significant tolerance to focal cerebral ischemia. The present study seeks to determine the involvement of monocyte chemotactic protein-induced protein 1 (MCPIP1), a recently identified novel modulator of inflammatory reactions, in the cerebral neuroprotection conferred by EA pretreatment in the animal model of focal cerebral ischemia and to elucidate the mechanisms of EA pretreatment-induced ischemic brain tolerance. Methods Twenty-four hours after the end of the last EA pretreatment, focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 90 minutes in male C57BL/6 mice and MCPIP1 knockout mice. Transcription and expression of MCPIP1 gene was monitored by qRT-PCR, Western blot and immunohistochemistry. The neurobehavioral scores, infarction volumes, proinflammatory cytokines and leukocyte infiltration in brain and NF-κB signaling were evaluated after ischemia/reperfusion. Results MCPIP1 protein and mRNA levels significantly increased specifically in mouse brain undergoing EA pretreatment. EA pretreatment significantly attenuated the infarct volume, neurological deficits, upregulation of proinflammatory cytokines and leukocyte infiltration in the brain of wild-type mice after MCAO compared with that of the non-EA group. MCPIP1-deficient mice failed to evoke EA pretreatment-induced tolerance compared with that of the control MCPIP1 knockout group without EA treatment. Furthermore, the activation of NF-κB signaling was significantly reduced in EA-pretreated wild-type mice after MCAO compared to that of the non-EA control group and MCPIP1-deficient mice failed to confer the EA pretreatment-induced inhibition of NF-κB signaling after MCAO. Conclusions Our data demonstrated that MCPIP1 deficiency caused significant lack of EA pretreatment-induced cerebral protective effects after MCAO compared with the control group and that MCPIP1 is

Preservation of endothelium-dependent relaxation in atherosclerotic mice with endothelium-restricted endothelin-1 overexpression.

Science.gov (United States)

Mian, Muhammad Oneeb Rehman; Idris-Khodja, Noureddine; Li, Melissa W; Leibowitz, Avshalom; Paradis, Pierre; Rautureau, Yohann; Schiffrin, Ernesto L

2013-10-01

In human atherosclerosis, which is associated with elevated plasma and coronary endothelin (ET)-1 levels, ETA receptor antagonists improve coronary endothelial function. Mice overexpressing ET-1 specifically in the endothelium (eET-1) crossed with atherosclerosis-prone apolipoprotein E knockout mice (Apoe(-/-)) exhibit exaggerated high-fat diet (HFD)-induced atherosclerosis. Since endothelial dysfunction often precedes atherosclerosis development, we hypothesized that mice overexpressing endothelial ET-1 on a genetic background deficient in apolipoprotein E (eET-1/Apoe(-/-)) would have severe endothelial dysfunction. To test this hypothesis, we investigated endothelium-dependent relaxation (EDR) to acetylcholine in eET-1/Apoe(-/-) mice. EDR in mesenteric resistance arteries from 8- and 16-week-old mice fed a normal diet or HFD was improved in eET-1/Apoe(-/-) compared with Apoe(-/-) mice. Nitric oxide synthase (NOS) inhibition abolished EDR in Apoe(-/-). EDR in eET-1/Apoe(-/-) mice was resistant to NOS inhibition irrespective of age or diet. Inhibition of cyclooxygenase, the cytochrome P450 pathway, and endothelium-dependent hyperpolarization (EDH) resulted in little or no inhibition of EDR in eET-1/Apoe(-/-) compared with wild-type (WT) mice. In eET-1/Apoe(-/-) mice, blocking of EDH or soluble guanylate cyclase (sGC), in addition to NOS inhibition, decreased EDR by 36 and 30%, respectively. The activation of 4-aminopyridine-sensitive voltage-dependent potassium channels (Kv) during EDR was increased in eET-1/Apoe(-/-) compared with WT mice. We conclude that increasing eET-1 in mice that develop atherosclerosis results in decreased mutual dependence of endothelial signaling pathways responsible for EDR, and that NOS-independent activation of sGC and increased activation of Kv are responsible for enhanced EDR in this model of atherosclerosis associated with elevated endothelial and circulating ET-1.

Relationship between insulin resistance and plasma endothelin in hypertension patients

International Nuclear Information System (INIS)

Duan Yongqiang; Wang Zuobing; Yu Hui; Cao Wei; Wang Jing; Li Xiaoqin

2011-01-01

To explore the relationship between plasma endothelin and hypertension insulin resistance, and the improvement of insulin resistance in hypertension patients treated with captopril and l-amlodipine, 25 patients with primary hypertension and impaired glucose tolerance were selected and treated by captopril and l-amlodipine. Systolic pressure, diastolic pressure, fasting blood glucose, insulin and insulin antibody were measured before and after treatment and compared with healthy controls. The results showed that the plasma ET-1 level in hypertension group was significantly higher than that of healthy controls (P<0.01), and he plasma ET-1 level was positively correlated with FPG, FINS, Anti-INS, HOMA-IR. The systolic pressure, diastolic pressure, fasting blood glucose, insulin, insulin antibody and insulin resistance index in hypertension patients were decreased significantly after treatment (P<0.05). There is a good correlation between endothelin and insulin resistance index in hypertension patients. Captopril and l-amlodipine had obvious improvement effect on insulin resistance in hypertension patients. (authors)

Down-regulation of endothelin binding sites in rat vascular smooth muscle cells

International Nuclear Information System (INIS)

Roubert, P.; Gillard, V.; Plas, P.; Chabrier, P.E.; Braquet, P.

1990-01-01

In cultured rat aortic smooth muscle cells, [ 125 I]endothelin (ET-1) bound to an apparent single class of high affinity recognition sites with a dissociation constant of 1.84 +/- 0.29 nmol/L and a maximum binding of 62 +/- 10.5 fmol/10(6) cells. The binding was not affected by calcium antagonists or vasoactive substances, including angiotensin II, arginine vasopressin, atrial natriuretic factor and bradykinin. Exposure of the cells to ET-1 (0.01 nmol/L to 10 nmol/L) resulted in an apparent dose-dependent reduction of the number of endothelin binding sites with no significant modification of its binding affinity. The time course of the down-regulation of ET-1 binding sites showed that this effect was present after 30 min incubation and persisted after 18 h. This indicates that down-regulation of ET-1 binding sites can modulate the activity of ET-1 and suggests a rapid internalization of ET-1 in vascular cells

Influence of radiographic contrast media (Iodixanol and Iomeprol) on the endothelin-1 release from human arterial and venous endothelial cells cultured on an extracellular matrix.

Science.gov (United States)

Franke, R P; Fuhrmann, R; Hiebl, B; Jung, F

2012-01-01

Various radiographic contrast media (RCM) are available for visualization of blood vessels in interventional cardiology which can vary widely in their physicochemical properties thereby influencing different functions of blood cells. In the in vitro study described here the influence of two RCMs on arterial as well as on venous endothelial cells was compared to control cultures and examined under statical culture conditions, thus eliminating the influence of RCM viscosity almost completely. The supplementation of the culture medium with RCM (30% v/v) resulted in clearly different reactions of the endothelial cells exposed. Exposition to Iodixanol supplemented culture medium was followed by endothelin-1 release from venous endothelial cells which was equivalent to the endothelin-1 release from venous control cultures. Compared to control cultures, venous endothelial cells exposed to culture medium supplemented with Iomeprol displayed a completely different reaction, the increase in endothelin-1 secretion was missing completely after a 12 hours exposure. Following a 12 hours exposure to both RCMs there were no longer endothelial cells adherent, neither in venous nor in arterial endothelial cell cultures. The study showed that not the wall shear stress was responsible for the differing effects visible after 1.5 min, 5 min, and 12 hours exposure to culture media supplemented with RCM but differences in chemotoxicity of the RCM applied.

Stimulation of phospholipase C in cultured microvascular endothelial cells from human frontal lobe by histamine, endothelin and purinoceptor agonists.

Science.gov (United States)

Purkiss, J. R.; West, D.; Wilkes, L. C.; Scott, C.; Yarrow, P.; Wilkinson, G. F.; Boarder, M. R.

1994-01-01

1. Cultures of endothelial cells derived from the microvasculature of human frontal lobe have been investigated for phospholipase C (PLC) responses to histamine, endothelins and purinoceptor agonists. 2. Using cells prelabelled with [3H]-inositol and measuring total [3H]-inositol (poly)phosphates, histamine acting at H1 receptors stimulated a substantial response with an EC50 of about 10 microM. 3. Endothelin-1 also gave a clear stimulation of phosphoinositide-specific phospholipase C. Both concentration-response curves and binding curves showed effective responses and binding in the rank order of endothelin-1 > sarafotoxin S6b > endothelin-3, suggesting an ETA receptor. 4. Assay of total [3H]-inositol (poly)phosphates showed no response to the purinoceptor agonists, 2-methylthioadenosine 5'-trisphosphate (2MeSATP), adenosine 5'-O-(3-thiotrisphosphate) (ATP gamma S) or beta,gamma-methylene ATP. Both ATP and UTP gave a small PLC response. 5. Similarly, when formation of [32P]-phosphatidic acid from cells prelabelled with 32Pi was used as an index of both PLC and phospholipase D, a small response to ATP and UTP was seen but there was no response to the other purinoceptor agonists tested. 6. Study by mass assay of stimulation by ATP of inositol (1,4,5) trisphosphate accumulation revealed a transient response in the first few seconds, a decline to basal, followed by a small sustained response. 7. These results show that human brain endothelial cells in culture are responsive to histamine and endothelins in a manner which may regulate brain capillary permeability. Purines exert a lesser influence. PMID:8032588

Overexpression of endothelin B receptor in glioblastoma: a prognostic marker and therapeutic target?

KAUST Repository

Vasaikar, Suhas; Tsipras, Giorgos; Landá zuri, Natalia; Costa, Helena; Wilhelmi, Vanessa; Scicluna, Patrick; Cui, Huanhuan L.; Mohammad, Abdul-Aleem; Davoudi, Belghis; Shang, Mingmei; Ananthaseshan, Sharan; Strå å t, Klas; Stragliotto, Giuseppe; Rahbar, Afsar; Wong, Kum Thong; Tegner, Jesper; Yaiw, Koon-Chu; Sö derberg-Naucler, Cecilia

2018-01-01

of endothelin B receptor (ETBR) has been demonstrated in gliomas, we aimed to test whether ETBR is a useful prognostic marker in GBM and examine if the clinically available endothelin receptor antagonists (ERA) could be useful in the disease treatment

Endothelin type B (ETB) receptors: friend or foe in the pathogenesis of pre-eclampsia and future cardiovascular disease (CVD) risk?

Science.gov (United States)

Mirabito Colafella, Katrina M

2018-01-16

In a recent issue of Clinical Science, Stanhewicz et al. investigated persistent microvascular dysfunction in women up to 16 months postpartum. The authors found sensitivity to the pressor effects of endothelin-1 (ET-1) was enhanced when compared with women who had a normotensive pregnancy. Importantly, the authors demonstrated that this effect was mediated via the endothelin type B (ET B ) receptors. Therefore, the present study highlights the possibility that alterations in the localization of the ET B receptor contributes to the pathogenesis of pre-eclampsia and future cardiovascular disease (CVD) risk. Currently, there is great interest in the role of the endothelin system in pre-eclampsia. Targetting the endothelin system, potentially by modulating upstream pathways to prevent ET B receptor dysfunction, may improve health outcomes for women and their offspring during pre-eclampsia and later life. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Knockout of endothelial cell-derived endothelin-1 attenuates skin fibrosis but accelerates cutaneous wound healing.

Directory of Open Access Journals (Sweden)

Katsunari Makino

Full Text Available Endothelin (ET-1 is known for the most potent vasoconstrictive peptide that is released mainly from endothelial cells. Several studies have reported ET-1 signaling is involved in the process of wound healing or fibrosis as well as vasodilation. However, little is known about the role of ET-1 in these processes. To clarify its mechanism, we compared skin fibrogenesis and wound repair between vascular endothelial cell-specific ET-1 knockout mice and their wild-type littermates. Bleomycin-injected fibrotic skin of the knockout mice showed significantly decreased skin thickness and collagen content compared to that of wild-type mice, indicating that bleomycin-induced skin fibrosis is attenuated in the knockout mice. The mRNA levels of transforming growth factor (TGF-β were decreased in the bleomycin-treated skin of ET-1 knockout mice. On the other hand, skin wound healing was accelerated in ET-1 knockout mice, which was indicated by earlier granulation tissue reduction and re-epithelialization in these mice. The mRNA levels of TGF-β, tumor necrosis factor (TNF-α and connective tissue growth factor (CTGF were reduced in the wound of ET-1 knockout mice. In endothelial ET-1 knockout mouse, the expression of TNF-α, CTGF and TGF-β was down-regulated. Bosentan, an antagonist of dual ET receptors, is known to attenuate skin fibrosis and accelerate wound healing in systemic sclerosis, and such contradictory effect may be mediated by above molecules. The endothelial cell-derived ET-1 is the potent therapeutic target in fibrosis or wound healing, and investigations of the overall regulatory mechanisms of these pathological conditions by ET-1 may lead to a new therapeutic approach.

Copper deficiency induced emphysema is associated with focal adhesion kinase inactivation.

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Shiro Mizuno

Full Text Available Copper is an important regulator of hypoxia inducible factor 1 alpha (HIF-1α dependent vascular endothelial growth factor (VEGF expression, and is also required for the activity of lysyl oxidase (LOX to effect matrix protein cross-linking. Cell detachment from the extracellular matrix can induce apoptosis (anoikis via inactivation of focal adhesion kinase (FAK.To examine the molecular mechanisms whereby copper depletion causes the destruction of the normal alveolar architecture via anoikis, Male Sprague-Dawley rats were fed a copper deficient diet for 6 weeks while being treated with the copper chelator, tetrathiomolybdate. Other groups of rats were treated with the inhibitor of auto-phosphorylation of FAK, 1,2,4,5-benzenetetraamine tetrahydrochloride (1,2,4,5-BT or FAK small interfering RNA (siRNA.Copper depletion caused emphysematous changes, decreased HIF-1α activity, and downregulated VEGF expression in the rat lungs. Cleaved caspase-3, caspase-8 and Bcl-2 interacting mediator of cell death (Bim expression was increased, and the phosphorylation of FAK was decreased in copper depleted rat lungs. Administration of 1,2,4,5-BT and FAK siRNA caused emphysematous lung destruction associated with increased expression of cleaved capase-3, caspase-8 and Bim.These data indicate that copper-dependent mechanisms contribute to the pathogenesis of emphysema, which may be associated with decreased HIF-1α and FAK activity in the lung.

Endothelins in chronic liver disease

DEFF Research Database (Denmark)

Møller, S; Henriksen, Jens Henrik Sahl

1996-01-01

renal failure. Studies on liver biopsies have revealed synthesis of ET-1 in hepatic endothelial and other cells, and recent investigations have identified the hepatosplanchnic system as a major source of ET-1 and ET-3 spillover into the circulation, with a direct relation to portal venous hypertension......This review describes recent progress in the accumulation of knowledge about the endothelins (ETs), a family of vasoactive 21-amino acid polypeptides, in chronic liver disease. Particular prominence is given to the dynamics of ET-1 and ET-3 and their possible relation to the disturbed circulation....... In addition, marked associations with disturbance of systemic haemodynamics and with abnormal distribution of blood volume have been reported. Although the pathophysiological importance of the ET system in chronic liver disease is not completely understood, similarities to other vasopressive...

Inhibition of CPU0213, a Dual Endothelin Receptor Antagonist, on Apoptosis via Nox4-Dependent ROS in HK-2 Cells

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Qing Li

2016-06-01

Full Text Available Background/Aims: Our previous studies have indicated that a novel endothelin receptor antagonist CPU0213 effectively normalized renal function in diabetic nephropathy. However, the molecular mechanisms mediating the nephroprotective role of CPU0213 remain unknown. Methods and Results: In the present study, we first detected the role of CPU0213 on apoptosis in human renal tubular epithelial cell (HK-2. It was shown that high glucose significantly increased the protein expression of Bax and decreased Bcl-2 protein in HK-2 cells, which was reversed by CPU0213. The percentage of HK-2 cells that showed Annexin V-FITC binding was markedly suppressed by CPU0213, which confirmed the inhibitory role of CPU0213 on apoptosis. Given the regulation of endothelin (ET system to oxidative stress, we determined the role of redox signaling in the regulation of CPU0213 on apoptosis. It was demonstrated that the production of superoxide (O2-. was substantially attenuated by CPU0213 treatment in HK-2 cells. We further found that CPU0213 dramatically inhibited expression of Nox4 protein, which gene silencing mimicked the role of CPU0213 on the apoptosis under high glucose stimulation. We finally examined the role of CPU0213 on ET-1 receptors and found that high glucose-induced protein expression of endothelin A and B receptors was dramatically inhibited by CPU0213. Conclusion: Taken together, these results suggest that this Nox4-dependenet O2- production is critical for the apoptosis of HK-2 cells in high glucose. Endothelin receptor antagonist CPU0213 has an anti-apoptosis role through Nox4-dependent O2-.production, which address the nephroprotective role of CPU0213 in diabetic nephropathy.

Focal ablation for atrial tachycardia from the double-exit of the Marshall bundle inducing atrial fibrillation

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Jung Yeon Chin, MD

2017-08-01

Full Text Available Atrial fibrillation (AF from the ligament/vein of Marshall (LOM/VOM has previously been described. We report the case of a 23-year-old woman with an antiarrhythmic drug-resistant AF induced by two distinct atrial tachycardias (ATs. Focal ablation of these ATs from the double-exit of the Marshall bundle using a three-dimensional map eliminated AF triggering, even though pulmonary vein electrical isolation is the cornerstone for paroxysmal AF. Such mechanisms are important as triggering factors to plan ablation for paroxysmal AF. Focal ablation for triggering and inducing AF, originating from the double-exit of the Marshall bundle may be effective in eliminating AF in young patients.

Expression of endothelin-1 gene and protein in human granulosa cells

Energy Technology Data Exchange (ETDEWEB)

Magini, A.; Granchi, S.; Susini, T. [Univ. of Florence (Italy)] [and others

1996-04-01

Previous studies in animal models indicated an autocrine/paracrine action of endothelin-1 (ET-1) in the ovary. We now report evidence on the presence of ET-1 in human ovary during reproductive life. Immunohistochemical and in situ hybridization studies demonstrated a positive signal into cytoplasm of granulosa cells (GC) of follicles at different growth stages. The concentration of ET-1-like immunoreactivity (ET-1-Li) was also measured by a specific RIA in human follicular fluid (FF). FF samples were obtained from women in an in vitro fertilization program undergoing gonadotropin stimulation (group A; n = 24) or no treatment (group B; n = 7). The mean ({+-}SD) ET-1-LI FF level in group A (4.85 {+-} 2.06 pg/mL) was significantly higher than that in group B (1.29 {+-} 0.43 pg/mL; P < 0.01), whereas the corresponding mean plasma levels were not significantly different and were not correlated to respective FF values. Our results indicate for the first time the presence of ET-1 and its messenger ribonucleic acid in the GC of the human ovary. The higher ET-1-LI levels found in the FF from women undergoing gonadotropin treatment suggest a modulation by gonadotropins and/or ovarian steroids of ET-1 production by GC. 19 refs., 4 figs., 1 tab.

Design and Rationale for the Endothelin-1 Receptor Antagonism in the Prevention of Microvascular Injury in Patients with non-ST Elevation Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention (ENDORA-PCI) Trial.

Science.gov (United States)

Liou, Kevin; Jepson, Nigel; Buckley, Nicolas; Chen, Vivien; Thomas, Shane; Russell, Elizabeth Anne; Ooi, Sze-Yuan

2016-04-01

Peri-procedural myocardial infarction (PMI) occurs in a small but significant portion of patients undergoing percutaneous intervention (PCI). The underlying mechanisms are complex and may include neurohormonal activation and release of vasoactive substances resulting in disruption of the coronary microcirculation. Endothelin in particular has been found in abundance in atherosclerotic plaques and in systemic circulation following PCI, and may be a potential culprit for PMI through its action on microvascular vasoconstriction, and platelet and neutrophil activation. In this study we aim to characterize the behavior of the coronary microcirculation during a PCI with the index of microvascular resistance (IMR) and the effect of peri-procedural endothelin antagonism. The ENDORA-PCI trial is a randomized, double-blind, placebo-controlled, single-center clinical trial designed to evaluate the efficacy of endothelin antagonism in attenuating the peri-procedural rise in IMR as a surrogate marker for PMI. The patients of interest are those with non-ST elevation acute coronary syndrome (NSTEACS) undergoing PCI, and we aim to recruit 52 patients overall to give the study a power of 80 % at an α level of 5 %. Patients will be randomized in a 1:1 fashion to either Ambrisentan, an endothelin antagonist, or placebo, prior to their PCI. IMR will be measured before and after PCI. The primary endpoint is the difference in peri-procedural changes in patients' IMR between the two groups. The ENDORA-PCI study will investigate whether endothelin antagonism with Ambrisentan attenuates the peri-procedural rise in IMR in patients with NSTEACS undergoing PCI, and thus potentially the risk of PMI.

Mutations in KCNT1 cause a spectrum of focal epilepsies

Science.gov (United States)

Møller, Rikke S.; Heron, Sarah E.; Larsen, Line H. G.; Lim, Chiao Xin; Ricos, Michael G.; Bayly, Marta A.; van Kempen, Marjan J. A.; Klinkenberg, Sylvia; Andrews, Ian; Kelley, Kent; Ronen, Gabriel M.; Callen, David; McMahon, Jacinta M.; Yendle, Simone C.; Carvill, Gemma L.; Mefford, Heather C.; Nabbout, Rima; Poduri, Annapurna; Striano, Pasquale; Baglietto, Maria G.; Zara, Federico; Smith, Nicholas J.; Pridmore, Clair; Gardella, Elena; Nikanorova, Marina; Dahl, Hans Atli; Gellert, Pia; Scheffer, Ingrid E.; Gunning, Boudewijn; Kragh-Olsen, Bente; Dibbens, Leanne M.

2018-01-01

Summary Autosomal dominant mutations in the sodium-gated potassium channel subunit gene KCNT1 have been associated with two distinct seizure syndromes, nocturnal frontal lobe epilepsy (NFLE) and malignant migrating focal seizures of infancy (MMFSI). To further explore the phenotypic spectrum associated with KCNT1, we examined individuals affected with focal epilepsy or an epileptic encephalopathy for mutations in the gene. We identified KCNT1 mutations in 12 previously unreported patients with focal epilepsy, multifocal epilepsy, cardiac arrhythmia, and in a family with sudden unexpected death in epilepsy (SUDEP), in addition to patients with NFLE and MMFSI. In contrast to the 100% penetrance so far reported for KCNT1 mutations, we observed incomplete penetrance. It is notable that we report that the one KCNT1 mutation, p.Arg398Gln, can lead to either of the two distinct phenotypes, ADNFLE or MMFSI, even within the same family. This indicates that genotype–phenotype relationships for KCNT1 mutations are not straightforward. We demonstrate that KCNT1 mutations are highly pleiotropic and are associated with phenotypes other than ADNFLE and MMFSI. KCNT1 mutations are now associated with Ohtahara syndrome, MMFSI, and nocturnal focal epilepsy. They may also be associated with multifocal epilepsy and cardiac disturbances. PMID:26122718

Amelioration of cold injury-induced cortical brain edema formation by selective endothelin ETB receptor antagonists in mice.

Science.gov (United States)

Michinaga, Shotaro; Nagase, Marina; Matsuyama, Emi; Yamanaka, Daisuke; Seno, Naoki; Fuka, Mayu; Yamamoto, Yui; Koyama, Yutaka

2014-01-01

Brain edema is a potentially fatal pathological condition that often occurs in stroke and head trauma. Following brain insults, endothelins (ETs) are increased and promote several pathophysiological responses. This study examined the effects of ETB antagonists on brain edema formation and disruption of the blood-brain barrier in a mouse cold injury model (Five- to six-week-old male ddY mice). Cold injury increased the water content of the injured cerebrum, and promoted extravasation of both Evans blue and endogenous albumin. In the injury area, expression of prepro-ET-1 mRNA and ET-1 peptide increased. Intracerebroventricular (ICV) administration of BQ788 (ETB antagonist), IRL-2500 (ETB antagonist), or FR139317 (ETA antagonist) prior to cold injury significantly attenuated the increase in brain water content. Bolus administration of BQ788, IRL-2500, or FR139317 also inhibited the cold injury-induced extravasation of Evans blue and albumin. Repeated administration of BQ788 and IRL-2500 beginning at 24 h after cold injury attenuated both the increase in brain water content and extravasation of markers. In contrast, FR139317 had no effect on edema formation when administrated after cold injury. Cold injury stimulated induction of glial fibrillary acidic protein-positive reactive astrocytes in the injured cerebrum. Induction of reactive astrocytes after cold injury was attenuated by ICV administration of BQ788 or IRL-2500. These results suggest that ETB receptor antagonists may be an effective approach to ameliorate brain edema formation following brain insults.

Evaluation of Homocysteine, Lipoprotein(a and Endothelin as diagnostic markers of Coronary Artery Disease in Indian population

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Vandana Saini

2013-01-01

Full Text Available Indians have been reported to have high prevalence rates of coronary artery disease (CAD even in the absence of traditional risk factors. The objective of this study was to assess the role of endothelin, lipoprotein(a, homocysteine and lipid profile as markers of CAD in Indian population. It was a hospital based observational case-control study, which included 60 documented patients of CAD, and 50 age and sex matched controls. Routine biochemical parameters were performed. Lipoprotein(a, homocysteine and endothelin levels were estimated by enzyme linked immunosorbent assay. The levels of endothelin (9.78±0.40 pg/ml vs. 7.86±0.31 pg/ml, lipoprotein(a (51.42±1.71 mg/dl vs. 36.26±1.21 mg/dl, homocysteine (21.31±1.22 µmol/L vs. 10.41±0.844 µmol/L and LDL/HDL cholesterol ratio (4.23±0.32 vs. 2.60±0.10 were significantly higher whereas that of HDL (29.82±1.39 mg/dl vs. 40.82±6.24 mg/dl was significantly lower in patients of CAD as compared to the controls (p0.7 for all the markers. Higher levels of homocysteine, endothelin, and lipoprotein(a were independently associated with increased risk of CAD. Thus, they may be helpful in risk assessment in premature cardiovascular disease and in individuals where traditional risk factors are not present.

Smooth Muscle Endothelin B Receptors Regulate Blood Pressure but Not Vascular Function or Neointimal Remodeling.

Science.gov (United States)

Miller, Eileen; Czopek, Alicja; Duthie, Karolina M; Kirkby, Nicholas S; van de Putte, Elisabeth E Fransen; Christen, Sibylle; Kimmitt, Robert A; Moorhouse, Rebecca; Castellan, Raphael F P; Kotelevtsev, Yuri V; Kuc, Rhoda E; Davenport, Anthony P; Dhaun, Neeraj; Webb, David J; Hadoke, Patrick W F

2017-02-01

The role of smooth muscle endothelin B (ET B ) receptors in regulating vascular function, blood pressure (BP), and neointimal remodeling has not been established. Selective knockout mice were generated to address the hypothesis that loss of smooth muscle ET B receptors would reduce BP, alter vascular contractility, and inhibit neointimal remodeling. ET B receptors were selectively deleted from smooth muscle by crossing floxed ET B mice with those expressing cre-recombinase controlled by the transgelin promoter. Functional consequences of ET B deletion were assessed using myography. BP was measured by telemetry, and neointimal lesion formation induced by femoral artery injury. Lesion size and composition (day 28) were analyzed using optical projection tomography, histology, and immunohistochemistry. Selective deletion of ET B was confirmed by genotyping, autoradiography, polymerase chain reaction, and immunohistochemistry. ET B -mediated contraction was reduced in trachea, but abolished from mesenteric veins, of knockout mice. Induction of ET B -mediated contraction in mesenteric arteries was also abolished in these mice. Femoral artery function was unaltered, and baseline BP modestly elevated in smooth muscle ET B knockout compared with controls (+4.2±0.2 mm Hg; P<0.0001), but salt-induced and ET B blockade-mediated hypertension were unaltered. Circulating endothelin-1 was not altered in knockout mice. ET B -mediated contraction was not induced in femoral arteries by incubation in culture medium or lesion formation, and lesion size was not altered in smooth muscle ET B knockout mice. In the absence of other pathology, ET B receptors in vascular smooth muscle make a small but significant contribution to ET B -dependent regulation of BP. These ET B receptors have no effect on vascular contraction or neointimal remodeling. © 2016 The Authors.

The Endothelin Type A Receptor as a Potential Therapeutic Target in Preeclampsia.

Science.gov (United States)

Bakrania, Bhavisha; Duncan, Jeremy; Warrington, Junie P; Granger, Joey P

2017-02-28

Preeclampsia (PE) is a disorder of pregnancy typically characterized by new onset hypertension after gestational week 20 and proteinuria. Although PE is one of the leading causes of maternal and perinatal morbidity and death worldwide, the mechanisms of the pathogenesis of the disease remain unclear and treatment options are limited. However, there is increasing evidence to suggest that endothelin-1 (ET-1) plays a critical role in the pathophysiology of PE. Multiple studies report that ET-1 is increased in PE and some studies report a positive correlation between ET-1 and the severity of symptoms. A number of experimental models of PE are also associated with elevated tissue levels of prepro ET-1 mRNA. Moreover, experimental models of PE (placental ischemia, sFlt-1 infusion, Tumor necrosis factor (TNF) -α infusion, and Angiotensin II type 1 receptor autoantibody (AT1-AA) infusion) have proven to be susceptible to Endothelin Type A (ET A ) receptor antagonism. While the results are promising, further work is needed to determine whether ET antagonists could provide an effective therapy for the management of preeclampsia.

Increased expression of vascular endothelin type B and angiotensin type 1 receptors in patients with ischemic heart disease

DEFF Research Database (Denmark)

Dimitrijevic, Ivan; Edvinsson, Lars; Chen, Qingwen

2009-01-01

expression in subcutaneous arteries from patients with different degrees of ischemic heart disease. METHODS: Subcutaneous arteries were obtained, by biopsy from the abdomen, from patients undergoing coronary artery bypass graft (CABG) surgery because of ischemic heart disease (n = 15), patients with angina...... pectoris without established myocardial infarction (n = 15) and matched cardiovascular healthy controls (n = 15). Endothelin type A (ETA) and type B (ETB), and angiotensin type 1 (AT1) and type 2 (AT2) receptors expression and function were examined using immunohistochemistry, Western blot and in vitro...

In depth pharmacological characterization of endothelin B receptors in the rat middle cerebral artery

DEFF Research Database (Denmark)

Szok, D; Hansen-Schwartz, J; Edvinsson, L

2001-01-01

Whereas the endothelin A receptor is generally believed to mediate vasoconstriction; the endothelin B receptor seems elusive; both dilative and constrictive responses have been reported. Using the in vitro arteriograph, a method allowing compartmentalized study of vessel segments, segments of rat...

Prognostic value of plasma midregional pro-adrenomedullin and C-terminal-pro-endothelin-1 in chronic heart failure outpatients.

Science.gov (United States)

Adlbrecht, Christopher; Hülsmann, Martin; Strunk, Guido; Berger, Rudolf; Mörtl, Deddo; Struck, Joachim; Morgenthaler, Nils G; Bergmann, Andreas; Jakowitsch, Johannes; Maurer, Gerald; Lang, Irene M; Pacher, Richard

2009-04-01

The identification of chronic heart failure (CHF) patients at high risk of adverse outcome remains a challenge. New peptides are emerging that may give additional information. In CHF patients, endothelin (ET) levels predict mortality risk. Adrenomedullin has been shown to predict mortality in ischaemic heart failure, but not in unselected or non-ischaemic CHF patients. Moreover, ADM and ET have never been assessed in one model. The aim of the present study was to assess the prognostic value of midregional-pro-adrenomedullin (MR-proADM) and C-terminal-pro-endothelin-1 (CT-proET-1) in outpatients with CHF. We measured plasma MR-proADM and CT-proET-1 levels in 786 consecutive CHF outpatients and compared them with B-type natriuretic peptide (BNP) levels. At 24-month follow-up, 233 patients had died. A stepwise forward Cox regression model with age, sex, estimated glomerular filtration rate, NYHA > II, left ventricular ejection fraction (LVEF), MR-proADM, CT-proET-1, and BNP as possible predictors revealed that MR-proADM levels [hazard ratio (HR) = 1.77, P II (HR = 1.86, P < 0.001) were predictors of death at 24 months. When the analysis was repeated dependent on NYHA-stage, MR-proADM (HR = 2.12, P < 0.001) and LVEF (HR = 0.96, P = 0.006) were significant markers, but only in patients with mild/moderate CHF. Our data suggest that MR-proADM may be an important prognostic humoral marker, especially in mild/moderately symptomatic and non-ischaemic CHF patients.

Structural determinants for selective recognition of peptide ligands for endothelin receptor subtypes ETA and ETB.

Science.gov (United States)

Lättig, Jens; Oksche, Alexander; Beyermann, Michael; Rosenthal, Walter; Krause, Gerd

2009-07-01

The molecular basis for recognition of peptide ligands endothelin-1, -2 and -3 in endothelin receptors is poorly understood. Especially the origin of ligand selectivity for ET(A) or ET(B) is not clearly resolved. We derived sequence-structure-function relationships of peptides and receptors from mutational data and homology modeling. Our major findings are the dissection of peptide ligands into four epitopes and the delineation of four complementary structural portions on receptor side explaining ligand recognition in both endothelin receptor subtypes. In addition, structural determinants for ligand selectivity could be described. As a result, we could improve the selectivity of BQ3020 about 10-fold by a single amino acid substitution, validating our hypothesis for ligand selectivity caused by different entrances to the receptors' transmembrane binding sites. A narrow tunnel shape in ET(A) is restrictive for a selected group of peptide ligands' N-termini, whereas a broad funnel-shaped entrance in ET(B) accepts a variety of different shapes and properties of ligands.

Facilitated beam-walking recovery during acute phase by kynurenic acid treatment in a rat model of photochemically induced thrombosis causing focal cerebral ischemia.

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Abo, Masahiro; Yamauchi, Hideki; Suzuki, Masahiko; Sakuma, Mio; Urashima, Mitsuyoshi

We previously demonstrated the presence of activated areas in the non-injured contralateral sensorimotor cortex in addition to the ipsilateral sensorimotor cortex of the area surrounding a brain infarction, using a rat model of focal photochemically induced thrombosis (PIT) and functional magnetic resonance imaging. Using this model, we next applied gene expression profiling to screen key molecules upregulated in the activated area. RNA was extracted from the ipsilateral and contralateral sensorimotor cortex to the focal brain infarction and from the sham controlled cortex, and hybridized to gene-expression profiling arrays containing 1,322 neurology-related genes. Results showed that glycine receptors were upregulated in both the ipsilateral and contralateral cortex to the focal ischemic lesion. To prove the preclinical significance of upregulated glycine receptors, kynurenic acid, an endogenous antagonist to glycine receptors on neuronal cells, was administered intrathecally. As a result, the kynurenic acid significantly improved behavioral recovery within 10 days from paralysis induced by the focal PIT (p beam walking. These results suggest that intrathecal administration of a glycine receptor antagonist may facilitate behavioral recovery during the acute phase after brain infarction. Copyright (c) 2006 S. Karger AG, Basel.

Hyperglycemia Induces Cellular Hypoxia through Production of Mitochondrial ROS Followed by Suppression of Aquaporin-1.

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Sada, Kiminori; Nishikawa, Takeshi; Kukidome, Daisuke; Yoshinaga, Tomoaki; Kajihara, Nobuhiro; Sonoda, Kazuhiro; Senokuchi, Takafumi; Motoshima, Hiroyuki; Matsumura, Takeshi; Araki, Eiichi

2016-01-01

We previously proposed that hyperglycemia-induced mitochondrial reactive oxygen species (mtROS) generation is a key event in the development of diabetic complications. Interestingly, some common aspects exist between hyperglycemia and hypoxia-induced phenomena. Thus, hyperglycemia may induce cellular hypoxia, and this phenomenon may also be involved in the pathogenesis of diabetic complications. In endothelial cells (ECs), cellular hypoxia increased after incubation with high glucose (HG). A similar phenomenon was observed in glomeruli of diabetic mice. HG-induced cellular hypoxia was suppressed by mitochondria blockades or manganese superoxide dismutase (MnSOD) overexpression, which is a specific SOD for mtROS. Overexpression of MnSOD also increased the expression of aquaporin-1 (AQP1), a water and oxygen channel. AQP1 overexpression in ECs suppressed hyperglycemia-induced cellular hypoxia, endothelin-1 and fibronectin overproduction, and apoptosis. Therefore, hyperglycemia-induced cellular hypoxia and mtROS generation may promote hyperglycemic damage in a coordinated manner.

Hyperglycemia Induces Cellular Hypoxia through Production of Mitochondrial ROS Followed by Suppression of Aquaporin-1.

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Kiminori Sada

Full Text Available We previously proposed that hyperglycemia-induced mitochondrial reactive oxygen species (mtROS generation is a key event in the development of diabetic complications. Interestingly, some common aspects exist between hyperglycemia and hypoxia-induced phenomena. Thus, hyperglycemia may induce cellular hypoxia, and this phenomenon may also be involved in the pathogenesis of diabetic complications. In endothelial cells (ECs, cellular hypoxia increased after incubation with high glucose (HG. A similar phenomenon was observed in glomeruli of diabetic mice. HG-induced cellular hypoxia was suppressed by mitochondria blockades or manganese superoxide dismutase (MnSOD overexpression, which is a specific SOD for mtROS. Overexpression of MnSOD also increased the expression of aquaporin-1 (AQP1, a water and oxygen channel. AQP1 overexpression in ECs suppressed hyperglycemia-induced cellular hypoxia, endothelin-1 and fibronectin overproduction, and apoptosis. Therefore, hyperglycemia-induced cellular hypoxia and mtROS generation may promote hyperglycemic damage in a coordinated manner.

Endothelin receptor-specific control of endoplasmic reticulum stress and apoptosis in the kidney.

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De Miguel, Carmen; Hamrick, William C; Hobbs, Janet L; Pollock, David M; Carmines, Pamela K; Pollock, Jennifer S

2017-02-23

Endothelin-1 (ET-1) promotes renal damage during cardiovascular disease; yet, the molecular mechanisms involved remain unknown. Endoplasmic reticulum (ER) stress, triggered by unfolded protein accumulation in the ER, contributes to apoptosis and organ injury. These studies aimed to determine whether the ET-1 system promotes renal ER stress development in response to tunicamycin. ET B deficient (ET B def) or transgenic control (TG-con) rats were used in the presence or absence of ET A receptor antagonism. Tunicamycin treatment similarly increased cortical ER stress markers in both rat genotypes; however, only ET B def rats showed a 14-24 fold increase from baseline for medullary GRP78, sXBP-1, and CHOP. Pre-treatment of TG-con rats with the ET A blocker ABT-627 for 1 week prior to tunicamycin injection significantly reduced the ER stress response in cortex and medulla, and also inhibited renal apoptosis. Pre-treatment with ABT-627 failed to decrease renal ER stress and apoptosis in ET B def rats. In conclusion, the ET-1 system is important for the development of tunicamycin-induced renal ER stress and apoptosis. ET A receptor activation induces renal ER stress genes and apoptosis, while functional activation of the ET B receptor has protective effects. These results highlight targeting the ET A receptor as a therapeutic approach against ER stress-induced kidney injury.

Lactoferrin- Endothelin-1 Axis Contributes to the Development and Invasiveness of Triple Negative Breast Cancer Phenotypes

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Ha, Ngoc-Han; Nair, Vasudha; Reddy, Divijendra Natha Sirigiri; Mudvari, Prakriti; Ohshiro, Kazufumi; Ghanta, Krishna Sumanth; Pakala, Suresh B.; Li, Da-Qiang; Costa, Luis; Lipton, Allan; Badwe, Rajendra A.; Fuqua, Suzanne; Wallon, Margaretha; Prendergast, George C.; Kumar, Rakesh

2013-01-01

Triple-negative breast cancer (TNBC) is characterized by the lack of expression of ERα, PR and HER-2 receptors and the pathway(s) responsible for this downregulation and thus aggressiveness, remains unknown. Here we discovered that lactoferrin (Lf) efficiently downregulates the levels of ERα, PR and HER-2 receptors in a proteasome-dependent manner in breast cancer cells, and accounts for the loss of responsiveness to ER- or HER-2- targeted therapies. Further we found that Lf increases migration and invasiveness of both non-TNBC and TNBC cell lines. We discovered that Lf directly stimulates the transcription of endothelin-1 (ET-1), a secreted pro-invasive polypeptide that acts through a specific receptor ET(A)R, leading to secretion of bioactive ET-1 peptide. Interestingly, a therapeutic ET-1 receptor antagonist drug completely blocked Lf-dependent motility and invasiveness of breast cancer cells. Physiologic significance of this newly discovered Lf-ET-1 axis in the manifestation of TNBC phenotypes is revealed by elevated plasma and tissue Lf and ET-1 levels in TNBC patients as compared to those in ER+ cases. These findings describe the first physiologically relevant polypeptide as a functional determinant of downregulating all three therapeutic receptors in breast cancer which utilizes another secreted ET-1 system to confer invasiveness. Results presented here provide proof-of-principle evidence in support of therapeutic effectiveness of ET-1 receptor antagonist to completely block the Lf-induced motility and invasiveness of the TNBC as well as non-TBNC cells, and thus, opening a remarkable opportunity to treat TNBC by targeting the Lf-ET-1 axis using an approved developmental drug. PMID:22006997

Intrahippocampal injection of endothelin-1 in immature rats results in neuronal death, development of epilepsy and behavioral abnormalities later in life

Czech Academy of Sciences Publication Activity Database

Máttéffyová, Adéla; Otáhal, Jakub; Tsenov, Grygoriy; Mareš, Pavel; Kubová, Hana

2006-01-01

Roč. 24, č. 2 (2006), s. 351-360 ISSN 0953-816X R&D Projects: GA ČR(CZ) GA305/06/0713; GA ČR(CZ) GD305/03/H148; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50110509 Keywords : endothelin-1 * epilepsy * immature rats Subject RIV: ED - Physiology Impact factor: 3.709, year: 2006

Sitaxsentan-Induced Acute Severe Hepatitis Treated with Glucocorticoid Therapy

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Marcus W Chin

2012-01-01

Full Text Available Endothelin receptor antagonists are commonly used in the treatment of pulmonary hypertension. Sitaxsentan, a selective endothelin A receptor blocker, induces a mild transaminitis in approximately 3% to 5% of patients, but rarely an acute severe hepatitis. A case involving a 61-year-old female with sitaxsentan-induced acute severe liver failure is presented. Depite withdrawal of therapy, her liver tests failed to improve. After six weeks of monitoring, the patient was administered high-dose corticosteroids, with a good clinical and biochemical response. While endothelin receptor antagonists are postulated to cause hepatitis by inhibition of a bile salt transporter pump, an immune-mediated or idiosyncratic mechanism should be considered.

Production of flat KrF laser focal profiles with echelon free-induced spatial incoherence

International Nuclear Information System (INIS)

Deniz, A.V.; Obenschain, S.P.; Pronko, M.; Lehmberg, R.H.

1990-01-01

High gain direct-drive laser fusion requires a uniform spherical pellet implosion. This in turn requires that the focal profile of each driving beam be sufficiently uniform and controlled. Several methods for producing uniform beams have been proposed. One promising technique, echelon free-induced spatial incoherence (ISI), consists of propagating a broadband spatially incoherent beam through an entire laser system. This technique will be used in the Nike laser, which is a twenty-four- to forty-eight-beam multikilojoule KrF system currently under construction at the Naval Research Laboratory (NRL). This paper presents measurements of focal profiles of laser light smoothed by echelon free ISI from a KrF oscillator and amplifier. The initial implementation is shown

Amelioration of cold injury-induced cortical brain edema formation by selective endothelin ETB receptor antagonists in mice.

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Shotaro Michinaga

Full Text Available Brain edema is a potentially fatal pathological condition that often occurs in stroke and head trauma. Following brain insults, endothelins (ETs are increased and promote several pathophysiological responses. This study examined the effects of ETB antagonists on brain edema formation and disruption of the blood-brain barrier in a mouse cold injury model (Five- to six-week-old male ddY mice. Cold injury increased the water content of the injured cerebrum, and promoted extravasation of both Evans blue and endogenous albumin. In the injury area, expression of prepro-ET-1 mRNA and ET-1 peptide increased. Intracerebroventricular (ICV administration of BQ788 (ETB antagonist, IRL-2500 (ETB antagonist, or FR139317 (ETA antagonist prior to cold injury significantly attenuated the increase in brain water content. Bolus administration of BQ788, IRL-2500, or FR139317 also inhibited the cold injury-induced extravasation of Evans blue and albumin. Repeated administration of BQ788 and IRL-2500 beginning at 24 h after cold injury attenuated both the increase in brain water content and extravasation of markers. In contrast, FR139317 had no effect on edema formation when administrated after cold injury. Cold injury stimulated induction of glial fibrillary acidic protein-positive reactive astrocytes in the injured cerebrum. Induction of reactive astrocytes after cold injury was attenuated by ICV administration of BQ788 or IRL-2500. These results suggest that ETB receptor antagonists may be an effective approach to ameliorate brain edema formation following brain insults.

Systematic study of the focal shift effect in planar plasmonic slit lenses

International Nuclear Information System (INIS)

Hu Bin; Wang Qijie; Zhang Ying

2012-01-01

In this paper, we systematically studied the focal shift effect in planar plasmonic slit lenses. Through theoretical derivations and numerical simulations, we found that there is a focal length shift between the traditional design model and the finite-difference time-domain simulations. The shift is not only dependent on the Fresnel number (FN) of the lens, like traditional dielectric lenses, determined by the lens width and the designed focal length, but also on the surface plasmon polariton (SPPs) interaction on the lens surfaces, dependent on the slit numbers. We also found that the FN-induced focal shift is predominant when FN 1. An approximated theoretical model is presented to estimate the focal shift of plasmonic slit lens with FN < 1. (paper)

Elevated endothelin-1 (ET-1) levels may contribute to hypoadiponectinemia in childhood obesity.

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Nacci, Carmela; Leo, Valentina; De Benedictis, Leonarda; Carratù, Maria Rosaria; Bartolomeo, Nicola; Altomare, Maria; Giordano, Paola; Faienza, Maria Felicia; Montagnani, Monica

2013-04-01

Pediatric obesity is associated with endothelial dysfunction and hypoadiponectinemia, but the relationship between these two conditions remains to be fully clarified. Whether enhanced release of endothelin-1 (ET-1) may directly impair adiponectin (Ad) production in obese children is not known. The aim of the study was to explore whether and how high circulating levels of ET-1 may contribute to impair Ad production, release, and vascular activity. Sixty children were included into obese (Ob; n = 30), overweight (OW; n = 11), and lean (n = 19) groups. Total and high-molecular-weight Ad, ET-1, vascular cell adhesion molecule-1, and von Willebrand factor levels were measured in serum samples. Adipocytes were stimulated with exogenous ET-1 or with sera from lean, OW, and Ob, and Ad production and release measured in the absence or in the presence of ETA (BQ-123) and ETB (BQ-788) receptor blockers, p42/44 MAPK inhibitor PD-98059, or c-Jun NH2-terminal protein kinase inhibitor SP-600125. Vasodilation to Ad was evaluated in rat isolated arteries in the absence or in the presence of BQ-123/788. Total and high-molecular-weight Ad was significantly decreased and ET-1 levels significantly increased in OW (P ET-1. Exposure of adipocytes to exogenous ET-1 or serum from OW and Ob significantly decreased Ad mRNA and protein levels (P ET-1 on Ad was reverted by BQ-123/788 or PD-98059 but not SP-600125. Ad-mediated vasodilation was further increased in arteries pretreated with BQ-123/788. ET-1-mediated inhibition of Ad synthesis via p42/44 MAPK signaling may provide a possible explanation for hypoadiponectinemia in pediatric obesity and contribute to the development of cardiovascular complications.

Effects of endothelin, calcium channel blockade and EDRF inhibition on the contractility of human uteroplacental arteries.

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Fried, G; Liu, Y A

1994-08-01

In order to examine the possibility that endothelin might be important in the regulation of placental blood flow, human uteroplacental vessels were superfused in vitro to study the contractile effect of endothelin as compared with a known strong contractor of placental blood vessels, serotonin (5-HT). The contractile responses were compared in the presence and absence of calcium channel blocking agents, as well as in the presence of L-NMA, an inhibitor of EDRF/nitric oxide. Endothelin (ET, 10(-10)-10(-6) M) and 5-HT (10(-8)-10(-4) M) induced contractions in the vessels. Maximal contractions in the presence of endothelin were elicited at 10(-7) M, whereas 5-HT elicited maximal contractions at 10(-5) M. At 10(-7) M, ET was more potent than 5-HT. The calcium-channel blocking agents nifedipine, diltiazem and NiCl2 relaxed the vessels by 5-15% from baseline. The contractile response to ET in the presence of nifedipine or diltiazem was reduced by 55 and 67%, respectively. The response of 5-HT in the presence of nifedipine was reduced by 58%. The contractile response to 5-HT as well as ET in the presence of both nifedipine and NiCl2 was not significantly lower than in the presence of nifedipine only. The EDRF-inhibiting agent L-NMA caused a small contractile response at concentrations of 10(-6)-10(-5) M. ET as well as 5-HT added after pretreatment with L-NMA produced a larger contractile response than ET or 5-HT alone. The results show that ET has a strong contractile effect on placental blood vessels at concentrations likely to occur during labor and delivery. The mechanism whereby ET as well as 5-HT contracts placental vessel smooth muscle appears to partly involve nifedipine- and diltiazem-sensitive calcium channels, but almost half of the response depends on mobilization of calcium through other means.

Slow receptor dissociation kinetics differentiate macitentan from other endothelin receptor antagonists in pulmonary arterial smooth muscle cells.

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John Gatfield

Full Text Available Two endothelin receptor antagonists (ERAs, bosentan and ambrisentan, are currently approved for the treatment of pulmonary arterial hypertension (PAH, a devastating disease involving an activated endothelin system and aberrant contraction and proliferation of pulmonary arterial smooth muscle cells (PASMC. The novel ERA macitentan has recently concluded testing in a Phase III morbidity/mortality clinical trial in PAH patients. Since the association and dissociation rates of G protein-coupled receptor antagonists can influence their pharmacological activity in vivo, we used human PASMC to characterize inhibitory potency and receptor inhibition kinetics of macitentan, ambrisentan and bosentan using calcium release and inositol-1-phosphate (IP(1 assays. In calcium release assays macitentan, ambrisentan and bosentan were highly potent ERAs with K(b values of 0.14 nM, 0.12 nM and 1.1 nM, respectively. Macitentan, but not ambrisentan and bosentan, displayed slow apparent receptor association kinetics as evidenced by increased antagonistic potency upon prolongation of antagonist pre-incubation times. In compound washout experiments, macitentan displayed a significantly lower receptor dissociation rate and longer receptor occupancy half-life (ROt(1/2 compared to bosentan and ambrisentan (ROt(1/2:17 minutes versus 70 seconds and 40 seconds, respectively. Because of its lower dissociation rate macitentan behaved as an insurmountable antagonist in calcium release and IP(1 assays, and unlike bosentan and ambrisentan it blocked endothelin receptor activation across a wide range of endothelin-1 (ET-1 concentrations. However, prolongation of the ET-1 stimulation time beyond ROt(1/2 rendered macitentan a surmountable antagonist, revealing its competitive binding mode. Bosentan and ambrisentan behaved as surmountable antagonists irrespective of the assay duration and they lacked inhibitory activity at high ET-1 concentrations. Thus, macitentan is a competitive

Endothelin 1 gene is not a major modifier of chronic kidney disease advancement among the autosomal dominant polycystic kidney disease patients

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Annapareddy Shiva Nagendra Reddy

2016-01-01

Full Text Available Introduction: Autosomal dominant polycystic kidney disease (ADPKD is characterized by the presence of numerous cysts in the kidney and manifest with various renal and extra-renal complications leading to ESRD. Endothelin may contribute to various renal and extra-renal manifestations pointing to genetic and environmental modifying factors that alter the risk of developing chronic kidney disease (CKD in ADPKD. In the present study we investigated six genes coding for endothelin 1 (EDN1 tagging-single nucleotide polymorphisms (tag-SNPs to unravel the EDN1 gene modifier effect for renal disease progression in ADPKD. Materials and Methods: The tag-SNPs were genotyped using FRET-based KASPar method in 108 ADPKD patients and 119 healthy subjects. Cochran-Armitage trend test was used to determine the association between ADPKD and EDN1 tag-SNPs. Multivariate logistic regression analysis was performed to assess the effect of tag-SNPs on CKD progression. The relationship between different CKD stages and hypertension and their interaction Mantel-Haenszel stratified analysis was performed. Results: All loci are polymorphic and followed Hardy-Weinberg equilibrium. Distribution of EDN1 genotypes and haplotypes in control and ADPKD is not statistically significant. Five SNPs covering 3.4 kb forming single LD block, but the LD was not strong between SNPs. The EDN1 genotypes are not contributing to the CKD advancement among the ADPKD patients. Conclusion: These results suggest that the EDN1 gene is not a major modifier of CKD advancement among ADPKD patients.

Specific receptor for endothelin in cultured rat cardiocytes

International Nuclear Information System (INIS)

Hirata, Y.; Fukuda, Y.; Yoshimi, H.; Emori, T.; Shichiri, M.; Marumo, F.

1989-01-01

Specific binding sites for the endothelium-derived vasoconstrictor endothelin (ET) and its effect on cytosolic free Ca2+ concentrations [( Ca2+]i) were studied in a primary culture of cardiocytes from neonatal rats. Binding studies using 125 I-labeled-porcine ET as a radioligand revealed the presence of a single class of high-affinity binding sites for ET in cardiocytes with an apparent Kd of 6-9 x 10(-10) M and a Bmax of 50,000-80,000 sites/cell. Neither various vasoconstrictors nor Ca2+-channel blockers affected the binding. Pretreatment with ET substantially reduced the total number of ET receptors without changing their affinity. ET dose-dependently increased [Ca2+]i in fura-2-loaded cardiocytes. These data indicate that cardiocytes have specific ET receptors that are controlled by a down-regulation mechanism, and that ET induces a receptor-mediated increase in [Ca2+]i in cardiocytes

Endothelin‐1 mediates natriuresis but not polyuria during vitamin D‐induced acute hypercalcaemia

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Tokonami, Natsuko; Cheval, Lydie; Monnay, Isabelle; Meurice, Guillaume; Loffing, Johannes; Feraille, Eric

2017-01-01

Key points Hypercalcaemia can occur under various pathological conditions, such as primary hyperparathyroidism, malignancy or granulomatosis, and it induces natriuresis and polyuria in various species via an unknown mechanism.A previous study demonstrated that hypercalcaemia induced by vitamin D in rats increased endothelin (ET)‐1 expression in the distal nephron, which suggests the involvement of the ET system in hypercalcaemia‐induced effects.In the present study, we demonstrate that, during vitamin D‐induced hypercalcaemia, the activation of ET system by increased ET‐1 is responsible for natriuresis but not for polyuria.Vitamin D‐treated hypercalcaemic mice showed a blunted response to amiloride, suggesting that epithelial sodium channel function is inhibited.We have identified an original pathway that specifically mediates the effects of vitamin D‐induced hypercalcaemia on sodium handling in the distal nephron without affecting water handling. Abstract Acute hypercalcaemia increases urinary sodium and water excretion; however, the underlying molecular mechanism remains unclear. Because vitamin D‐induced hypercalcaemia increases the renal expression of endothelin (ET)‐1, we hypothesized that ET‐1 mediates the effects of hypercalcaemia on renal sodium and water handling. Hypercalcaemia was induced in 8‐week‐old, parathyroid hormone‐supplemented, male mice by oral administration of dihydrotachysterol (DHT) for 3 days. DHT‐treated mice became hypercalcaemic and displayed increased urinary water and sodium excretion compared to controls. mRNA levels of ET‐1 and the transcription factors CCAAT‐enhancer binding protein β and δ were specifically increased in the distal convoluted tubule and downstream segments in DHT‐treated mice. To examine the role of the ET system in hypercalcaemia‐induced natriuresis and polyuria, mice were treated with the ET‐1 receptor antagonist macitentan, with or without DHT. Mice treated with both

Endothelin mechanisms in altered thyroid states in the rat.

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Rebello, S; Thompson, E B; Gulati, A

1993-06-11

Endothelin (ET) and its receptor characteristics were studied in hyper- and hypo-thyroid states in the rats. Hyperthyroidism was induced by daily administration of thyroxine (0.1 mg/kg i.p.) for 8 weeks, while hypothyrodism was induced by daily administration of methimazole (10 mg/kg i.p.) for 8 weeks. The chronic administration of thyroxine to rats decreased their rate of gain of body weight, increased serum T3 and T4 concentration, blood pressure and heart rate. The chronic administration of methimazole decreased the rate of gain of body weight, serum T3 and T4 concentration, blood pressure and heart rate as compared to vehicle-treated control. Plasma ET-1 levels were found to be similar in control and methimazole-treated rats, while the levels were found to be significantly (P < 0.002) increased in thyroxine-treated rats as compared to control rats. Binding studies showed that [125I]ET-1 bound to a single, high affinity binding site in the cerebral cortex, hypothalamus and pituitary. The density (Bmax) and the affinity (Kd) of [125I]ET-1 binding in the cerebral cortex and hypothalamus were found to be similar in control, methimazole- and thyroxine-treated rats. The pituitary of thyroxine-treated rats showed a decrease in the binding (34.3% decrease in the density) of [125I]ET-1 as compared to control rats. No difference was observed in the binding of [125I]ET-1 to pituitary membranes from control and methimazole-treated rats. Competition studies showed that the IC50 and Ki values of ET-3 for [125]ET-1 binding were about 8 to 11 times higher than ET-1 in cerebral cortex, hypothalamus and pituitary.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemin offers neuroprotection through inducing exogenous neuroglobin in focal cerebral hypoxic-ischemia in rats

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Song, Xue; Xu, Rui; Xie, Fei; Zhu, Haiyuan; Zhu, Ji; Wang, Xin

2014-01-01

Objective: To investigate the inducible effect of hemin on exogenous neuroglobin (Ngb) in focal cerebral hypoxic-ischemia in rats. Methods: 125 healthy SD rats were randomly divided into five groups: sham-operation control group, operation group, hemin treatment group, exogenous Ngb treatment group, and hemin and exogenous Ngb joint treatment group. Twenty-four hours after focal cerebral hypoxic-ischemia, Ngb expression was evaluated by immunocytochemistry, RT-PCR, and western blot analyses, while the brain water content and infarct volume were examined. Results: Immunocytochemistry, RT-PCR, and western blot analyses showed more pronounced Ngb expression in the hemin and exogenous Ngb joint operation group than in the hemin or exogenous Ngb individual treatment groups, thus producing significant differences in brain water content and infarct volume (p exogenous Ngb. PMID:24966924

Interactive HIV-1 Tat and morphine-induced synaptodendritic injury is triggered through focal disruptions in Na⁺ influx, mitochondrial instability, and Ca²⁺ overload.

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Fitting, Sylvia; Knapp, Pamela E; Zou, Shiping; Marks, William D; Bowers, M Scott; Akbarali, Hamid I; Hauser, Kurt F

2014-09-17

Synaptodendritic injury is thought to underlie HIV-associated neurocognitive disorders and contributes to exaggerated inflammation and cognitive impairment seen in opioid abusers with HIV-1. To examine events triggering combined transactivator of transcription (Tat)- and morphine-induced synaptodendritic injury systematically, striatal neuron imaging studies were conducted in vitro. These studies demonstrated nearly identical pathologic increases in dendritic varicosities as seen in Tat transgenic mice in vivo. Tat caused significant focal increases in intracellular sodium ([Na(+)]i) and calcium ([Ca(2+)]i) in dendrites that were accompanied by the emergence of dendritic varicosities. These effects were largely, but not entirely, attenuated by the NMDA and AMPA receptor antagonists MK-801 and CNQX, respectively. Concurrent morphine treatment accelerated Tat-induced focal varicosities, which were accompanied by localized increases in [Ca(2+)]i and exaggerated instability in mitochondrial inner membrane potential. Importantly, morphine's effects were prevented by the μ-opioid receptor antagonist CTAP and were not observed in neurons cultured from μ-opioid receptor knock-out mice. Combined Tat- and morphine-induced initial losses in ion homeostasis and increases in [Ca(2+)]i were attenuated by the ryanodine receptor inhibitor ryanodine, as well as pyruvate. In summary, Tat induced increases in [Na(+)]i, mitochondrial instability, excessive Ca(2+) influx through glutamatergic receptors, and swelling along dendrites. Morphine, acting via μ-opioid receptors, exacerbates these excitotoxic Tat effects at the same subcellular locations by mobilizing additional [Ca(2+)]i and by further disrupting [Ca(2+)]i homeostasis. We hypothesize that the spatiotemporal relationship of μ-opioid and aberrant AMPA/NMDA glutamate receptor signaling is critical in defining the location and degree to which opiates exacerbate the synaptodendritic injury commonly observed in neuro

Homocysteine, endothelin-1 and nitric oxide in patients with hypertensive disorders complicating pregnancy.

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Zeng, Yachang; Li, Mujun; Chen, Yue; Wang, Sumei

2015-01-01

To investigate the change of level of serum homocysteine (Hcy), endothelin-1 (ET-1) and nitric oxide (NO) and clinical significance in patients with HDCP. Two hundred and thirty nine patients with HDCP (137 patients with mild preeclampsia, 102 patients with severe preeclampsia) who were hospitalized between June 2012 and June 2015 and 200 normal pregnancy women in outpatient department were enrolled in our study were divided into HDCP group and control group. Serum Hcy concentration was measured by enzymatic cycling assay. ET-1 concentration was measured by enzyme linked immunosorbent assay. And no concentration was measured by nitrate reductase assay. Serum Hcy and ET-1 in HDCP group were significantly higher as compared to control group (Ppreclampsia group (P<0.05). Level of serum NO in severe preeclampsia group were significantly lower than in mild preeclampsia group (P<0.05). Spearman rank correlation analysis showed that level of serum Hcy and ET-1 was positively correlated with severity of diseases (r=0.689, 0.718, P<0.05). Level of serum NO was negatively correlated with severity of diseases (r=-0.702, P<0.05). Serum Hcy, ET-1 and NO were associated with pathogenesis of HDCP. Comprehensively measurement of them could effectively evaluate the incidence and progress of HDCP.

Characterization of [125I]endothelin-1 binding sites in rat cardiac membrane fragments

International Nuclear Information System (INIS)

Gu, X.H.; Casley, D.J.; Nayler, W.G.

1989-01-01

Standard binding and displacement techniques were used to identify high-affinity binding sites for [ 125 I]-labeled endothelin-1 (ET-1) in membranes harvested from the hearts of adult female Sprague-Dawley rats. A single population of binding sites was identified, with a KD of 0.20 +/- 0.03 nM at 37 degrees C, and a Bmax of 93.5 +/- 6.4 fmol/mg protein. Bound [ 125 I]ET-1 was displaced by ET-1 (10(-13)-10(-8) M), with a Ki of 0.08 nM. Neither (-)Bay K 8644 (10(-11)-10(-5) M), prenylamine (10(-11)-10(-5) M), (+)-cis-diltiazem (10(-10)-10(-5) M), (-)D888 (10(-10)-10(-5) M), nicardipine (10(-10)-10(-5) M), lidoflazine (10(-11)-10(-5) M), flunarizine (10(-11)-10(-5) M), omega-conotoxin (10(-13)-10(-7) M), nor prazosin (10(-10)-10(-5) M) displaced the bound ligand. Binding occurred in the absence of Ca2+ and was absent in heat-denatured membranes. These results are interpreted to mean that [ 125 I]ET-1 binds to a single class of high-affinity binding sites that differ from those occupied by known regulators of voltage activated L- and N-type Ca2+ channels

Liberación de endotelina-1 por angiotensina ll en miocitos cardíacos aislados Angiotensin II-induced endothelin-1 release in cardiac myocytes

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María C. Villa-Abrille

2006-06-01

Full Text Available Muchos de los efectos de la angiotensina II (Ang II son mediados en realidad por la acción de endotelina (ET endógena liberada y/o producida en respuesta a la Ang II. En este trabajo evaluamos la interacción Ang II/ET-1, sus consecuencias en la contractilidad cardíaca y el papel de las especies reactivas del oxígeno (EROs. Se usaron cardiomiocitos aislados de gato. La Ang II, 1 nM, produjo un efecto inotrópico positivo (EIP de 31.8±3.8% que fue cancelado por inhibición de los receptores AT1, de los receptores de ET, del intercambiador Na+/H+ (NHE, del modo inverso del intercambiador Na+/Ca2+ (NCX o por el secuestro de EROs. La Ang II, 100 nM, produjo un EIP de 70.5±7.6% que fue cancelado por inhibición de los receptores AT1 y bloqueado en parte por inhibición de los receptores de ET, del NHE, del modo inverso del NCX o por el secuestro de EROs. La Ang II, 1 nM, incrementó el ARNm de la preproET-1 lo cual fue anulado por el bloqueo de los receptores AT1. Los resultados permiten concluir que el EIP de la Ang II es debido a la acción de la ET-1 endógena liberada/formada por la Ang II. La ET-1 produce: estimulación del NHE, activación del modo inverso del NCX y un consecuente EIP. Dentro de esta cascada también participarían los EROs.Many of the effects thought to be due to angiotensin II (Ang II are due to the release/formation of endothelin (ET. We tested whether Ang II elicits its positive inotropic effect (PIE by the action of endogenous ET-1 and the role played by the reactive oxygen species (ROS in this mechanism. Experiments were performed in cat isolated ventricular myocytes in which sarcomere shortening (SS was measured to asses contractility after pharmacological interventions and the effect of Ang II on inotropism were analyzed. Ang II 1 nM increased SS by 31.8±3.8% (p<0.05. This PIE was cancelled by AT1 receptor blockade, by ET-1 receptors blockade, by Na+/H+ exchanger (NHE inhibition, by reverse mode Na+/Ca2

Electric field depth-focality tradeoff in transcranial magnetic stimulation: simulation comparison of 50 coil designs.

Science.gov (United States)

Deng, Zhi-De; Lisanby, Sarah H; Peterchev, Angel V

2013-01-01

Various transcranial magnetic stimulation (TMS) coil designs are available or have been proposed. However, key coil characteristics such as electric field focality and attenuation in depth have not been adequately compared. Knowledge of the coil focality and depth characteristics can help TMS researchers and clinicians with coil selection and interpretation of TMS studies. To quantify the electric field focality and depth of penetration of various TMS coils. The electric field distributions induced by 50 TMS coils were simulated in a spherical human head model using the finite element method. For each coil design, we quantified the electric field penetration by the half-value depth, d(1/2), and focality by the tangential spread, S(1/2), defined as the half-value volume (V(1/2)) divided by the half-value depth, S(1/2) = V(1/2)/d(1/2). The 50 TMS coils exhibit a wide range of electric field focality and depth, but all followed a depth-focality tradeoff: coils with larger half-value depth cannot be as focal as more superficial coils. The ranges of achievable d(1/2) are similar between coils producing circular and figure-8 electric field patterns, ranging 1.0-3.5 cm and 0.9-3.4 cm, respectively. However, figure-8 field coils are more focal, having S(1/2) as low as 5 cm(2) compared to 34 cm(2) for circular field coils. For any coil design, the ability to directly stimulate deeper brain structures is obtained at the expense of inducing wider electrical field spread. Novel coil designs should be benchmarked against comparison coils with consistent metrics such as d(1/2) and S(1/2). Copyright © 2013 Elsevier Inc. All rights reserved.

Experimental Focal Cerebral Ischemia

DEFF Research Database (Denmark)

Christensen, Thomas

2007-01-01

Focal cerebral ischemia due to occlusion of a major cerebral artery is the cause of ischemic stroke which is a major reason of mortality, morbidity and disability in the populations of the developed countries. In the seven studies summarized in the thesis focal ischemia in rats induced by occlusion...... in the penumbra is recruited in the infarction process leading to a progressive growth of the infarct. The penumbra hence constitutes an important target for pharmacological treatment because of the existence of a therapeutic time window during which treatment with neuroprotective compounds may prevent...

Expression profile of endothelin receptors (ETA and ETB) and microRNAs-155 and -199 in the corpus cavernosum of rats submitted to chronic alcoholism and diabetes mellitus.

Science.gov (United States)

Gonçalves, F Z; Lizarte Neto, F S; Novais, P C; Gattas, D; Lourenço, L G; de Carvalho, C A M; Tirapelli, D P C; Molina, C A F; Tirapelli, L F; Tucci, S

2018-03-01

Recent evidence shows that chronic ethanol consumption increases endothelin (ET)-1 induced sustained contraction of trabecular smooth muscle cells of the corpora cavernosa in corpus cavernosum of rats by a mechanism that involves increased expression of ETA and ETB receptors. Our goal was to evaluate the effects of alcohol and diabetes and their relationship to miRNA-155, miRNA-199 and endothelin receptors in the corpus cavernosum and blood of rats submitted to the experimental model of diabetes mellitus and chronic alcoholism. Forty-eight male Wistar rats were divided into four groups: control (C), alcoholic (A), diabetic (D), and alcoholic-diabetic (AD). Samples of the corpus cavernosum were prepared to study the protein expression of endothelin receptors by immunohistochemistry and expression of miRNAs-155 and -199 in serum and the cavernous tissue. Immunostaining for endothelin receptors was markedly higher in the A, D, and AD groups than in the C group. Moreover, a significant hypoexpression of the miRNA-199 in the corpus cavernosum tissue from the AD group was observed, compared to the C group. When analyzing the microRNA profile in blood, a significant hypoexpression of miRNA-155 in the AD group was observed compared to the C group. The miRNA-199 analysis demonstrated significant hypoexpression in D and AD groups compared to the C group. Our findings in corpus cavernosum showed downregulated miRNA-155 and miRNA-199 levels associated with upregulated protein expression and unaltered mRNA expression of ET receptors suggesting decreased ET receptor turnover, which can contribute to erectile dysfunction in diabetic rats exposed to high alcohol levels.

Expression profile of endothelin receptors (ETA and ETB and microRNAs-155 and -199 in the corpus cavernosum of rats submitted to chronic alcoholism and diabetes mellitus

Directory of Open Access Journals (Sweden)

F.Z. Gonçalves

2018-03-01

Full Text Available Recent evidence shows that chronic ethanol consumption increases endothelin (ET-1 induced sustained contraction of trabecular smooth muscle cells of the corpora cavernosa in corpus cavernosum of rats by a mechanism that involves increased expression of ETA and ETB receptors. Our goal was to evaluate the effects of alcohol and diabetes and their relationship to miRNA-155, miRNA-199 and endothelin receptors in the corpus cavernosum and blood of rats submitted to the experimental model of diabetes mellitus and chronic alcoholism. Forty-eight male Wistar rats were divided into four groups: control (C, alcoholic (A, diabetic (D, and alcoholic-diabetic (AD. Samples of the corpus cavernosum were prepared to study the protein expression of endothelin receptors by immunohistochemistry and expression of miRNAs-155 and -199 in serum and the cavernous tissue. Immunostaining for endothelin receptors was markedly higher in the A, D, and AD groups than in the C group. Moreover, a significant hypoexpression of the miRNA-199 in the corpus cavernosum tissue from the AD group was observed, compared to the C group. When analyzing the microRNA profile in blood, a significant hypoexpression of miRNA-155 in the AD group was observed compared to the C group. The miRNA-199 analysis demonstrated significant hypoexpression in D and AD groups compared to the C group. Our findings in corpus cavernosum showed downregulated miRNA-155 and miRNA-199 levels associated with upregulated protein expression and unaltered mRNA expression of ET receptors suggesting decreased ET receptor turnover, which can contribute to erectile dysfunction in diabetic rats exposed to high alcohol levels.

Culture of human intestinal epithelial cell using the dissociating enzyme thermolysin and endothelin-3

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Z. Liu

2010-05-01

Full Text Available Epithelium, a highly dynamic system, plays a key role in the homeostasis of the intestine. However, thus far a human intestinal epithelial cell line has not been established in many countries. Fetal tissue was selected to generate viable cell cultures for its sterile condition, effective generation, and differentiated character. The purpose of the present study was to culture human intestinal epithelial cells by a relatively simple method. Thermolysin was added to improve the yield of epithelial cells, while endothelin-3 was added to stimulate their growth. By adding endothelin-3, the achievement ratio (viable cell cultures/total cultures was enhanced to 60% of a total of 10 cultures (initiated from 8 distinct fetal small intestines, allowing the generation of viable epithelial cell cultures. Western blot, real-time PCR and immunofluorescent staining showed that cytokeratins 8, 18 and mouse intestinal mucosa-1/39 had high expression levels in human intestinal epithelial cells. Differentiated markers such as sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV also showed high expression levels in human intestinal epithelial cells. Differentiated human intestinal epithelial cells, with the expression of surface markers (cytokeratins 8, 18 and mouse intestinal mucosa-1/39 and secretion of cytokines (sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV, may be cultured by the thermolysin and endothelin-3 method and maintained for at least 20 passages. This is relatively simple, requiring no sophisticated techniques or instruments, and may have a number of varied applications.

Vascular reactivity of mesenteric arteries and veins to endothelin-1 in a murine model of high blood pressure.

Science.gov (United States)

Pérez-Rivera, Alex A; Fink, Gregory D; Galligan, James J

2005-06-01

We characterized vascular reactivity to endothelin-1 (ET-1) in mesenteric vessels from DOCA-salt hypertensive and SHAM control mice and assessed the effect that endothelial-derived vasodilators have on ET-1-induced vasoconstriction. Changes in the diameter of unpressurized small mesenteric arteries and veins (100- to 300-microm outside diameter) were measured in vitro using computer-assisted video microscopy. Veins were more sensitive than arteries to the contractile effects of ET-1. There was a decrease in arterial maximal responses (E(max)) compared to veins, this effect was larger in DOCA-salt arteries. The selective ET(B) receptor agonist, sarafotoxin 6c (S6c), contracted DOCA-salt and SHAM veins but did not contract arteries. The ET(B) receptor antagonist, BQ-788 (100 nM), but not the ET(A) receptor antagonist, BQ-610 (100 nM), blocked S6c responses. BQ-610 partially inhibited responses to ET-1 in mesenteric veins from DOCA-salt and SHAM mice while BQ-788 did not affect responses to ET-1. Co-administration of both antagonists inhibited responses to ET-1 to a greater extent than BQ-610 alone suggesting a possible functional interaction between ET(A) and ET(B) receptors. Responses to ET-1 in mesenteric arteries were completely inhibited by BQ-610 while BQ-788 did not affect arterial responses. Nitric oxide synthase inhibition potentiated ET-1 responses in veins from SHAM but not DOCA-salt mice. There was a prominent role for ET-mediated nitric oxide release in DOCA-salt but not SHAM arteries. In summary, these studies showed a differential regulation of ET-1 contractile mechanisms between murine mesenteric arteries and veins.

Stimuli of sensory-motor nerves terminate arterial contractile effects of endothelin-1 by CGRP and dissociation of ET-1/ET(A)-receptor complexes

DEFF Research Database (Denmark)

Meens, Merlijn J P M T; Compeer, Matthijs G; Hackeng, Tilman M

2010-01-01

of the antagonists and (ii) can be selectively dissociated by an endogenous counterbalancing mechanism. METHODOLOGY/PRINCIPAL FINDINGS: In isolated rat mesenteric resistance arteries, ET(A)-antagonists, endothelium-derived relaxing factors and synthetic vasodilators transiently reduced contractile effects of ET-1......BACKGROUND: Endothelin-1 (ET-1), a long-acting paracrine mediator, is implicated in cardiovascular diseases but clinical trials with ET-receptor antagonists were not successful in some areas. We tested whether the quasi-irreversible receptor-binding of ET-1 (i) limits reversing effects...... but did not prevent persistent effects of the peptide. Stimuli of peri-vascular vasodilator sensory-motor nerves such as capsaicin not only reduced but also terminated long-lasting effects of ET-1. This was prevented by CGRP-receptor antagonists and was mimicked by exogenous calcitonin gene...

Interleukin 1β induces rapid phosphorylation and redistribution of talin: A possible mechanism for modulation of fibroblast focal adhesion

International Nuclear Information System (INIS)

Qwarnstroem, E.E.; MacFarlane, S.A.; Page, R.C.; Dower, S.K.

1991-01-01

The majority of interleukin 1 (IL-1) receptors in human fibroblasts has been shown to be localized at focal adhesions. This study describes rapid alterations caused by IL-1β/IL-1-receptor interaction at these sites. Fibroblast monolayers, incubated with IL-1β and prepared for electron microscopy, showed successive loss of cell-substratum contact and fewer and less-pronounced processes. Immunocytochemistry revealed loss and redistribution of the talin staining initially observed after 5-15 min of IL-1β incubation. Similarly, the cytoskeleton showed a decrease in staining and a disorganization starting from 15 to 30 min after IL-1 addition, whereas extracellular fibronectin appeared largely unaffected. Prelabeling with [ 32 P]phosphate showed a 2- to 3-fold increase in the level of talin phosphorylation, peaking at 15 min. Phospho amino acid analyses revealed a higher level of serine and threonine phosphorylation. The data suggest that the action of IL-1β on fibroblasts may be partially mediated by direct phosphorylation of talin via activation of a protein serine/threonine kinase, leading to changes in transmembrane linkage proteins and the cytoskeleton. Such alterations at focal adhesions may provide a mechanism by which IL-1 can rapidly modulate cell-matrix interactions during inflammation and wound healing

Influence of the distance between target surface and focal point on the expansion dynamics of a laser-induced silicon plasma with spatial confinement

Science.gov (United States)

Zhang, Dan; Chen, Anmin; Wang, Xiaowei; Wang, Ying; Sui, Laizhi; Ke, Da; Li, Suyu; Jiang, Yuanfei; Jin, Mingxing

2018-05-01

Expansion dynamics of a laser-induced plasma plume, with spatial confinement, for various distances between the target surface and focal point were studied by the fast photography technique. A silicon wafer was ablated to induce the plasma with a Nd:YAG laser in an atmospheric environment. The expansion dynamics of the plasma plume depended on the distance between the target surface and focal point. In addition, spatially confined time-resolved images showed the different structures of the plasma plumes at different distances between the target surface and focal point. By analyzing the plume images, the optimal distance for emission enhancement was found to be approximately 6 mm away from the geometrical focus using a 10 cm focal length lens. This optimized distance resulted in the strongest compression ratio of the plasma plume by the reflected shock wave. Furthermore, the duration of the interaction between the reflected shock wave and the plasma plume was also prolonged.

Role of Protein Kinase C in Endothelin Converting Enzyme-1 trafficking and shedding from endothelial cells

Energy Technology Data Exchange (ETDEWEB)

Kuruppu, Sanjaya, E-mail: Sanjaya.Kuruppu@med.monash.edu.au [Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, Vic. 3800 (Australia); Tochon-Danguy, Natalie; Ian Smith, A. [Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, Vic. 3800 (Australia)

2010-07-23

Research highlights: {yields} PKC activation increases the trafficking of ECE-1 to the cell surface. {yields} This in turn leads to an increase in the amount of ECE-1 shed. {yields} Only the catalytically active C-terminal region is shed from the cell surface. -- Abstract: This study aimed to determine the consequences of Protein Kinase C (PKC) mediated Endothelin Converting Enzyme-1 (ECE-1) phosphorylation and its relationship to ECE-1 expression and shedding. The proteins on the surface of EA.hy926 cells were labelled with EZ-Link NHS-SS-Biotin both prior to (control) and following stimulation by 2 {mu}M phorbol 12-myristate 13-acetate (PMA) which activates PKC. The biotinylated proteins were isolated using neutravidin beads, resolved by gel electrophoresis and analysed by western blotting using anti-ECE-1 antibodies. Significant increase in ECE-1 expression at the cell surface was observed following stimulation by PMA, compared to unstimulated control cells (170 {+-} 32.3% of control, n = 5). The ECE-1 activity (expressed as {mu}M substrate cleaved/min) was determined by monitoring the cleavage of a quenched fluorescent substrate. The specificity of cleavage was confirmed using the ECE-1 inhibitor (CGS35066). The stimulation of cells by PMA (1 {mu}M, 6 h) significantly increased the ECE-1 activity (0.28 {+-} 0.02; n = 3) compared to the control (0.07 {+-} 0.02; n = 3). This increase was prevented by prior incubation with the PKC inhibitor bisindolymaleimide (BIM; 2 {mu}M for 1 h; 0.10 {+-} 0.01; n = 3). Treatment with PMA also increased the activity of ECE-1 in the media (0.18 {+-} 0.01; n = 3) compared to control (0.08 {+-} 0.01; n = 3). In addition, this study confirmed by western immunoblotting that only the extracellular region of ECE-1 is released from the cell surface. These data indicate for the first time that PKC activation induces the trafficking and shedding of ECE to and from the cell surface, respectively.

Clinical significance of determination of plasma endothelin (ET) and homocysteine (Hcy) levels in patients with diabetic nephropathy

International Nuclear Information System (INIS)

Zhang Aimin; Jin Ying; Zhou Xiu

2005-01-01

Objective: To determine the plasma levels of endothelin (ET) and homocysteine (Hcy) in patients with diabetic nephropathy. Methods: Plasma ET (with RIA) and Hcy( with electrochemiluminescence) contents were determined in 32 DM2 patients without nephropathy, 35 DM2 patients with nephropathy and 30 controls. Results: Endothelin and homocysteine levels were significantly higher in patients with diabetic nephropathy than those in patients without nephropathy and controls (P<0.05- 0.01). Conclusion: Endothelin and homocysteine were involved in the pathogenesis of diabetic nephropathy, and determination of which were of diagnostic and prognostic value in clinical practice. (authors)

Evaluation of Homocysteine, Lipoprotein(a) and Endothelin as ...

African Journals Online (AJOL)

Indians have been reported to have high prevalence rates of coronary artery disease (CAD) even in the absence of traditional risk factors. The objective of this study was to assess the role of endothelin, lipoprotein(a), homocysteine and lipid profile as markers of CAD in Indian population. It was a hospital based ...

Endothelin receptor antagonism in single ventricle physiology with fontan palliation: A systematic review and meta-analysis

Directory of Open Access Journals (Sweden)

Gwendolyn Derk

2015-04-01

Conclusions: Bosentan was found to be a safe and well tolerated endothelin receptor antagonist in Fontan patients over 3–6 months of therapy. Bosentan use was associated with improved functional capacity. Future studies with larger sample size and longer duration are warranted to examine the long-term safety and efficacy of endothelin blockade in Fontan physiology.

Radiation-Induced Transient Effects in Near Infrared Focal Plane Arrays

Science.gov (United States)

Reed, Robert A.; Pickel, J.; Marshall, P.; Waczynski, A.; McMurray, R.; Gee, G.; Polidan, E.; Johnson, S.; McKeivey, M.; Ennico, K.;

Down-regulation of hypoxia-inducible factor-1 alpha and vascular endothelial growth factor by HEXIM1 attenuates myocardial angiogenesis in hypoxic mice.

Science.gov (United States)

Yoshikawa, Noritada; Shimizu, Noriaki; Ojima, Hidenori; Kobayashi, Hiroshi; Hosono, Osamu; Tanaka, Hirotoshi

2014-10-24

Pulmonary hypertension (PH) sustains elevation of pulmonary vascular resistance and ultimately leads to right ventricular (RV) hypertrophy and failure and death. Recently, proangiogenic factors hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) have been known to promote left ventricular myocardial angiogenesis and lead to cardiac hypertrophy, and this would be involved in RV hypertrophy of PH patients. Previously, we revealed that overexpression of HEXIM1 prevents endothelin-1-induced cardiomyocyte hypertrophy and hypertrophic genes expression, and that cardiomyocyte-specific HEXIM1 transgenic mice ameliorates RV hypertrophy in hypoxia-induced PH model. Given these results, here we analyzed the effect of HEXIM1 on the expression of HIF-1α and VEGF and on myocardial angiogenesis of RV in PH. We revealed that overexpression of HEXIM1 prevented hypoxia-induced expression of HIF-1α protein and its target genes including VEGF in the cultured cardiac myocytes and fibroblasts, and that cardiomyocyte-specific HEXIM1 transgenic mice repressed RV myocardial angiogenesis in hypoxia-induced PH model. Thus, we conclude that HEXIM1 could prevent RV hypertrophy, at least in part, via suppression of myocardial angiogenesis through down-regulation of HIF-1α and VEGF in the myocardium under hypoxic condition. Copyright © 2014 Elsevier Inc. All rights reserved.

Comparison of plasma endothelin levels between osteoporotic, osteopenic and normal subjects

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Biçimoğlu Ali

2005-09-01

Full Text Available Abstract Background It has been demonstrated that endothelins (ET have significant roles in bone remodeling, metabolism and physiopathology of several bone diseases. We aimed to investigate if there was any difference between the plasma ET levels of osteoporotic patients and normals. Methods 86 patients (70 women and 16 men with a mean age of 62.6 (ranges: 51–90 years were included in this study. Patients were divided into groups of osteoporosis, osteopenia and normal regarding reported T scores of DEXA evaluation according to the suggestions of World Health Organization. According to these criteria 19, 43 and 24 were normal, osteopenic and osteoporotic respectively. Then total plasma level of ET was measured in all patients with monoclonal antibody based sandwich immunoassay (EIA method. One-way analysis of variance test was used to compare endothelin values between normals, osteopenics and osteoporotics. Results Endothelin total plasma level in patients was a mean of 98.36 ± 63.96, 100.92 ± 47.2 and 99.56 ± 56.6 pg/ml in osteoporotic, osteopenic and normal groups respectively. The difference between groups was not significant (p > 0.05. Conclusion No significant differences in plasma ET levels among three groups of study participants could be detected in this study.

Chronic high-sodium diet increases aortic wall endothelin-1 expression in a blood pressure-independent fashion in rats.

Science.gov (United States)

Tsai, Yu-Hwai; Ohkita, Mamoru; Gariepy, Cheryl E

2006-06-01

Vascular endothelin (ET)-1 is upregulated in several forms of salt-induced hypertension. It is unclear to what extent these effects are primary or secondary to endothelial damage. We hypothesized that a high-sodium diet (HNa) increases vascular ET-1 production independent of arterial blood pressure changes. We investigated the effect of chronic HNa with and without ET(A) blockade on circulating and aortic ET-1 protein levels as well as aortic expression of ET-1 and ET(A) messenger RNA (mRNA) in inbred Wistar-Kyoto (WKY) and congenic ET(B)-deficient rats. Comparing WKY rats fed a low-sodium diet (LNa) with those fed HNa for 3 weeks, aortic wall ET-1 protein is significantly increased in response to HNa (331 +/- 43 pg/g tissue for LNa vs. 557 +/- 34 pg/gm tissue for HNa). HNa also increased aortic wall ET-1 mRNA levels by 40%, as determined by quantitative reverse transcriptase polymerase chain reaction. We then compared rats chronically treated with the ET(A)-selective antagonist, ABT-627, while receiving either LNa or HNa. There were no differences in arterial blood pressure (mean arterial pressure 89 +/- 1 mm Hg for WKY on LNa; 90 +/- 3 for WKY on HNa; 91 +/- 2 for ET(B)-deficient/ABT-627-treated on HNa) or heart rate. However, aortic wall ET-1 protein levels were 4-fold higher in the HNa group. Further, HNa increased aortic wall ET-1 mRNA (approximately 1.5- to 3-fold) and ET(A) mRNA (approximately 2- to 7-fold), independent of activation of ET(B). Therefore, the expression of ET-1 mRNA by the aortic wall is increased in response to chronic high dietary sodium in WKY rats in the absence of changes in arterial blood pressure.

Interferon Induced Focal Segmental Glomerulosclerosis

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Yusuf Kayar

2016-01-01

Full Text Available Behçet’s disease is an inflammatory disease of unknown etiology which involves recurring oral and genital aphthous ulcers and ocular lesions as well as articular, vascular, and nervous system involvement. Focal segmental glomerulosclerosis (FSGS is usually seen in viral infections, immune deficiency syndrome, sickle cell anemia, and hyperfiltration and secondary to interferon therapy. Here, we present a case of FSGS identified with kidney biopsy in a patient who had been diagnosed with Behçet’s disease and received interferon-alpha treatment for uveitis and presented with acute renal failure and nephrotic syndrome associated with interferon.

Recurrent Bilateral Focal Myositis.

Science.gov (United States)

Nagafuchi, Hiroko; Nakano, Hiromasa; Ooka, Seido; Takakuwa, Yukiko; Yamada, Hidehiro; Tadokoro, Mamoru; Shimojo, Sadatomo; Ozaki, Shoichi

This report describes a rare case of recurrent bilateral focal myositis and its successful treatment via methotrexate. A 38-year-old man presented myalgia of the right gastrocnemius in May 2005. Magnetic resonance imaging showed very high signal intensity in the right gastrocnemius on short-tau inversion recovery images. A muscle biopsy revealed inflammatory CD4+ cell-dominant myogenic change. Focal myositis was diagnosed. The first steroid treatment was effective. Tapering of prednisolone, however, repeatedly induced myositis relapse, which progressed to multiple muscle lesions of both lower limbs. Initiation of methotrexate finally allowed successful tapering of prednisolone, with no relapse in the past 4 years.

Implementation of focal zooming on the Nike KrF laser

Energy Technology Data Exchange (ETDEWEB)

Kehne, D. M.; Karasik, M.; Weaver, J. L.; Chan, Y.; Obenschain, S. P. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Aglitsky, Y. [Science Applications International, McLean, Virginia 22150 (United States); Smyth, Z.; Lehmberg, R. H. [Research Support Instruments, Inc., Lanham, Maryland 20706 (United States); Terrell, S. [Commonwealth Technologies, Inc., Alexandria, Virginia 22315 (United States)

2013-01-15

In direct drive inertial confinement laser fusion, a pellet containing D-T fuel is imploded by ablation arising from absorption of laser energy at its outer surface. For optimal coupling, the focal spot of the laser would continuously decrease to match the reduction in the pellet's diameter, thereby minimizing wasted energy. A krypton-fluoride laser ({lambda}= 248 nm) that incorporates beam smoothing by induced spatial incoherence has the ability to produce a high quality focal profile whose diameter varies with time, a property known as focal zooming. A two-stage focal zoom has been demonstrated on the Nike laser at the Naval Research Laboratory. In the experiment, a 4.4 ns laser pulse was created in which the on-target focal spot diameter was 1.3 mm (full width at half maximum) for the first 2.4 ns and 0.28 mm for the final 2 ns. These two diameters appear in time-integrated focal plane equivalent images taken at several locations in the amplification chain. Eight of the zoomed output beams were overlapped on a 60 {mu}m thick planar polystyrene target. Time resolved images of self-emission from the rear of the target show the separate shocks launched by the two corresponding laser focal diameters.

Implementation of focal zooming on the Nike KrF laser

International Nuclear Information System (INIS)

Kehne, D. M.; Karasik, M.; Weaver, J. L.; Chan, Y.; Obenschain, S. P.; Aglitsky, Y.; Smyth, Z.; Lehmberg, R. H.; Terrell, S.

2013-01-01

In direct drive inertial confinement laser fusion, a pellet containing D-T fuel is imploded by ablation arising from absorption of laser energy at its outer surface. For optimal coupling, the focal spot of the laser would continuously decrease to match the reduction in the pellet's diameter, thereby minimizing wasted energy. A krypton-fluoride laser (λ= 248 nm) that incorporates beam smoothing by induced spatial incoherence has the ability to produce a high quality focal profile whose diameter varies with time, a property known as focal zooming. A two-stage focal zoom has been demonstrated on the Nike laser at the Naval Research Laboratory. In the experiment, a 4.4 ns laser pulse was created in which the on-target focal spot diameter was 1.3 mm (full width at half maximum) for the first 2.4 ns and 0.28 mm for the final 2 ns. These two diameters appear in time-integrated focal plane equivalent images taken at several locations in the amplification chain. Eight of the zoomed output beams were overlapped on a 60 μm thick planar polystyrene target. Time resolved images of self-emission from the rear of the target show the separate shocks launched by the two corresponding laser focal diameters.

Implementation of focal zooming on the Nike KrF laser

Science.gov (United States)

Kehne, D. M.; Karasik, M.; Aglitsky, Y.; Smyth, Z.; Terrell, S.; Weaver, J. L.; Chan, Y.; Lehmberg, R. H.; Obenschain, S. P.

2013-01-01

In direct drive inertial confinement laser fusion, a pellet containing D-T fuel is imploded by ablation arising from absorption of laser energy at its outer surface. For optimal coupling, the focal spot of the laser would continuously decrease to match the reduction in the pellet's diameter, thereby minimizing wasted energy. A krypton-fluoride laser (λ = 248 nm) that incorporates beam smoothing by induced spatial incoherence has the ability to produce a high quality focal profile whose diameter varies with time, a property known as focal zooming. A two-stage focal zoom has been demonstrated on the Nike laser at the Naval Research Laboratory. In the experiment, a 4.4 ns laser pulse was created in which the on-target focal spot diameter was 1.3 mm (full width at half maximum) for the first 2.4 ns and 0.28 mm for the final 2 ns. These two diameters appear in time-integrated focal plane equivalent images taken at several locations in the amplification chain. Eight of the zoomed output beams were overlapped on a 60 μm thick planar polystyrene target. Time resolved images of self-emission from the rear of the target show the separate shocks launched by the two corresponding laser focal diameters.

Blockade of Endothelin-1 Receptor Type B Ameliorates Glucose Intolerance and Insulin Resistance in a Mouse Model of Obstructive Sleep Apnea

Directory of Open Access Journals (Sweden)

Jan Polak

2018-05-01

Full Text Available Obstructive sleep apnea (OSA is associated with insulin resistance (IR and glucose intolerance. Elevated endothelin-1 (ET-1 levels have been observed in OSA patients and in mice exposed to intermittent hypoxia (IH. We examined whether pharmacological blockade of type A and type B ET-1 receptors (ETA and ETB would ameliorate glucose intolerance and IR in mice exposed to IH. Subcutaneously implanted pumps delivered BQ-123 (ETA antagonist; 200 nmol/kg/day, BQ-788 (ETB antagonist; 200 nmol/kg/day or vehicle (saline or propyleneglycol [PG] for 14 days in C57BL6/J mice (10/group. During treatment, mice were exposed to IH (decreasing the FiO2 from 20.9% to 6%, 60/h or intermittent air (IA. After IH or IA exposure, insulin (0.5 IU/kg or glucose (1 mg/kg was injected intraperitoneally and plasma glucose determined after injection and area under glucose curve (AUC was calculated. Fourteen-day IH increased fasting glucose levels (122 ± 7 vs. 157 ± 8 mg/dL, PG: 118 ± 6 vs. 139 ± 8; both p < 0.05 and impaired glucose tolerance (AUCglucose: 19,249 ± 1105 vs. 29,124 ± 1444, PG AUCglucose: 18,066 ± 947 vs. 25,135 ± 797; both p < 0.05 in vehicle-treated animals. IH-induced impairments in glucose tolerance were partially ameliorated with BQ-788 treatment (AUCglucose: 21,969 ± 662; p < 0.05. Fourteen-day IH also induced IR (AUCglucose: 7185 ± 401 vs. 8699 ± 401; p < 0.05. Treatment with BQ-788 decreased IR under IA (AUCglucose: 5281 ± 401, p < 0.05 and reduced worsening of IR with IH (AUCglucose: 7302 ± 401, p < 0.05. There was no effect of BQ-123 on IH-induced impairments in glucose tolerance or IR. Our results suggest that ET-1 plays a role in IH-induced impairments in glucose homeostasis.

Antibody mediated albuminuria and focal segmental glomerulosclerosis in Thy- 1.1 transgenic mice.

NARCIS (Netherlands)

Smeets, B.

2006-01-01

Focal segmental glomerulosclerosis (FSGS) is the hallmark of the glomerular lesion that is characteristically observed in failing kidneys. FSGS is one of the leading causes of renal insufficiency. In this thesis the Thy-1.1 transgenic mouse model was used as a model of FSGS. We particularly

Endothelin-2/Vasoactive Intestinal Contractor: Regulation of Expression via Reactive Oxygen Species Induced by CoCl22, and Biological Activities Including Neurite Outgrowth in PC12 Cells

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Eiichi Kotake-Nara

2006-01-01

Full Text Available This paper reviews the local hormone endothelin-2 (ET-2, or vasoactive intestinal contractor (VIC, a member of the vasoconstrictor ET peptide family, where ET-2 is the human orthologous peptide of the murine VIC. While ET-2/VIC gene expression has been observed in some normal tissues, ET-2 recently has been reported to act as a tumor marker and as a hypoxia-induced autocrine survival factor in tumor cells. A recently published study reported that the hypoxic mimetic agent CoCl2 at 200 µM increased expression of the ET-2/VIC gene, decreased expression of the ET-1 gene, and induced intracellular reactive oxygen species (ROS increase and neurite outgrowth in neuronal model PC12 cells. The ROS was generated by addition of CoCl2 to the culture medium, and the CoCl2-induced effects were completely inhibited by the antioxidant N-acetyl cysteine. Furthermore, interleukin-6 (IL-6 gene expression was up-regulated upon the differentiation induced by CoCl2. These results suggest that expression of ET-2/VIC and ET-1 mediated by CoCl2-induced ROS may be associated with neuronal differentiation through the regulation of IL-6 expression. CoCl2 acts as a pro-oxidant, as do Fe(II, III and Cu(II. However, some biological activities have been reported for CoCl2 that have not been observed for other metal salts such as FeCl3, CuSO4, and NiCl2. The characteristic actions of CoCl2 may be associated with the differentiation of PC12 cells. Further elucidation of the mechanism of neurite outgrowth and regulation of ET-2/VIC expression by CoCl2 may lead to the development of treatments for neuronal disorders.

Circulating levels of endothelin-1 in a homogenous Gulf Arab population with untreated essential hypertension.

Science.gov (United States)

Obineche, Enyioma; Abdulle, Abdishakur M; Bokhari, Awais M; Yasin, Javed Y; Gillett, Michael P T

2006-01-01

Racial variations are reported in the natural history of hypertension. For example, hypertension is significantly more prevalent in blacks than whites. Endothelial cells are important regulators of vascular tone and homeostasis, in part through secretions of vasoactive substances including endothelin-1 (ET-1), a small peptide with potent vasopressor actions. In black hypertensives, ET-1 levels are higher than in normotensive blacks and in both hypertensive and normotensive whites. Since ET-1 might play a significant role in the development and severity of hypertension in the indigenous Arab population of the United Arab Emirates, we investigated the circulating levels of ET-1 in this homogenous population. ET-1 levels were measured in plasma samples from 60 untreated hypertensive Arabs and compared with 60 age- and sex-matched normotensive controls. ET-1 levels were significantly higher in hypertensives (mean 10.1 +/- 1 pmol/L) than normotensives (mean 2.2 +/- 0.5 pmol/L). Body mass index (BMI) was slightly higher among the hypertensives. For all subjects these levels significantly (P Arabs as compared with reported levels in white hypertensives and ET-1 could be a risk factor for cardiovascular diseases in this population. The endothelial system might be particularly important with respect to hypertension in this racial group and merits further study.

Pharmacological hypothesis: Nitric oxide-induced inhibition of ADAM-17 activity as well as vesicle release can in turn prevent the production of soluble endothelin-converting enzyme.

Science.gov (United States)

Kuruppu, Sanjaya; Rajapakse, Niwanthi W; Parkington, Helena C; Smith, Ian

2017-10-01

Endothelin-1 (ET-1) and nitric oxide (NO) are two highly potent vasoactive molecules with opposing effects on the vasculature. Endothelin-converting enzyme (ECE) and nitric oxide synthase (NOS) catalyse the production of ET-1 and NO, respectively. It is well established that these molecules play a crucial role in the initiation and progression of cardiovascular diseases and have therefore become targets of therapy. Many studies have examined the mechanism(s) by which NO regulates ET-1 production. Expression and localization of ECE-1 is a key factor that determines the rate of ET-1 production. ECE-1 can either be membrane bound or be released from the cell surface to produce a soluble form. NO has been shown to reduce the expression of both membrane-bound and soluble ECE-1. Several studies have examined the mechanism(s) behind NO-mediated inhibition of ECE expression on the cell membrane. However, the precise mechanism(s) behind NO-mediated inhibition of soluble ECE production are unknown. We hypothesize that both exogenous and endogenous NO, inhibits the production of soluble ECE-1 by preventing its release via extracellular vesicles (e.g., exosomes), and/or by inhibiting the activity of A Disintegrin and Metalloprotease-17 (ADAM17). If this hypothesis is proven correct in future studies, these pathways represent targets for the therapeutic manipulation of soluble ECE-1 production. © 2017 The Authors. Pharmacology Research & Perspectives published by John Wiley & Sons Ltd, British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics.

Staurosporine augments EGF-mediated EMT in PMC42-LA cells through actin depolymerisation, focal contact size reduction and Snail1 induction – A model for cross-modulation

International Nuclear Information System (INIS)

Hugo, Honor J; Wafai, Razan; Blick, Tony; Thompson, Erik W; Newgreen, Donald F

2009-01-01

A feature of epithelial to mesenchymal transition (EMT) relevant to tumour dissemination is the reorganization of actin cytoskeleton/focal contacts, influencing cellular ECM adherence and motility. This is coupled with the transcriptional repression of E-cadherin, often mediated by Snail1, Snail2 and Zeb1/δEF1. These genes, overexpressed in breast carcinomas, are known targets of growth factor-initiated pathways, however it is less clear how alterations in ECM attachment cross-modulate to regulate these pathways. EGF induces EMT in the breast cancer cell line PMC42-LA and the kinase inhibitor staurosporine (ST) induces EMT in embryonic neural epithelial cells, with F-actin de-bundling and disruption of cell-cell adhesion, via inhibition of aPKC. PMC42-LA cells were treated for 72 h with 10 ng/ml EGF, 40 nM ST, or both, and assessed for expression of E-cadherin repressor genes (Snail1, Snail2, Zeb1/δEF1) and EMT-related genes by QRT-PCR, multiplex tandem PCR (MT-PCR) and immunofluorescence +/- cycloheximide. Actin and focal contacts (paxillin) were visualized by confocal microscopy. A public database of human breast cancers was assessed for expression of Snail1 and Snail2 in relation to outcome. When PMC42-LA were treated with EGF, Snail2 was the principal E-cadherin repressor induced. With ST or ST+EGF this shifted to Snail1, with more extreme EMT and Zeb1/δEF1 induction seen with ST+EGF. ST reduced stress fibres and focal contact size rapidly and independently of gene transcription. Gene expression analysis by MT-PCR indicated that ST repressed many genes which were induced by EGF (EGFR, CAV1, CTGF, CYR61, CD44, S100A4) and induced genes which alter the actin cytoskeleton (NLF1, NLF2, EPHB4). Examination of the public database of breast cancers revealed tumours exhibiting higher Snail1 expression have an increased risk of disease-recurrence. This was not seen for Snail2, and Zeb1/δEF1 showed a reverse correlation with lower expression values being predictive

Staurosporine augments EGF-mediated EMT in PMC42-LA cells through actin depolymerisation, focal contact size reduction and Snail1 induction – A model for cross-modulation

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Thompson Erik W

2009-07-01

Full Text Available Abstract Background A feature of epithelial to mesenchymal transition (EMT relevant to tumour dissemination is the reorganization of actin cytoskeleton/focal contacts, influencing cellular ECM adherence and motility. This is coupled with the transcriptional repression of E-cadherin, often mediated by Snail1, Snail2 and Zeb1/δEF1. These genes, overexpressed in breast carcinomas, are known targets of growth factor-initiated pathways, however it is less clear how alterations in ECM attachment cross-modulate to regulate these pathways. EGF induces EMT in the breast cancer cell line PMC42-LA and the kinase inhibitor staurosporine (ST induces EMT in embryonic neural epithelial cells, with F-actin de-bundling and disruption of cell-cell adhesion, via inhibition of aPKC. Methods PMC42-LA cells were treated for 72 h with 10 ng/ml EGF, 40 nM ST, or both, and assessed for expression of E-cadherin repressor genes (Snail1, Snail2, Zeb1/δEF1 and EMT-related genes by QRT-PCR, multiplex tandem PCR (MT-PCR and immunofluorescence +/- cycloheximide. Actin and focal contacts (paxillin were visualized by confocal microscopy. A public database of human breast cancers was assessed for expression of Snail1 and Snail2 in relation to outcome. Results When PMC42-LA were treated with EGF, Snail2 was the principal E-cadherin repressor induced. With ST or ST+EGF this shifted to Snail1, with more extreme EMT and Zeb1/δEF1 induction seen with ST+EGF. ST reduced stress fibres and focal contact size rapidly and independently of gene transcription. Gene expression analysis by MT-PCR indicated that ST repressed many genes which were induced by EGF (EGFR, CAV1, CTGF, CYR61, CD44, S100A4 and induced genes which alter the actin cytoskeleton (NLF1, NLF2, EPHB4. Examination of the public database of breast cancers revealed tumours exhibiting higher Snail1 expression have an increased risk of disease-recurrence. This was not seen for Snail2, and Zeb1/δEF1 showed a reverse

Identification of chronic heart failure patients with a high 12-month mortality risk using biomarkers including plasma C-terminal pro-endothelin-1.

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Ewa A Jankowska

Full Text Available OBJECTIVES: We hypothesised that assessment of plasma C-terminal pro-endothelin-1 (CT-proET-1, a stable endothelin-1 precursor fragment, is of prognostic value in patients with chronic heart failure (CHF, beyond other prognosticators, including N-terminal pro-B-type natriuretic peptide (NT-proBNP. METHODS: We examined 491 patients with systolic CHF (age: 63±11 years, 91% men, New York Heart Association [NYHA] class [I/II/III/IV]: 9%/45%/38%/8%, 69% ischemic etiology. Plasma CT-proET-1 was detected using a chemiluminescence immunoassay. RESULTS: Increasing CT-proET-1 was a predictor of increased cardiovascular mortality at 12-months of follow-up (standardized hazard ratio 1.42, 95% confidence interval [CI] 1.04-1.95, p = 0.03 after adjusting for NT-proBNP, left ventricular ejection fraction (LVEF, age, creatinine, NYHA class. In receiver operating characteristic curve analysis, areas under curve for 12-month follow-up were similar for CT-proET-1 and NT-proBNP (p = 0.40. Both NT-proBNP and CT-proET-1 added prognostic value to a base model that included LVEF, age, creatinine, and NYHA class. Adding CT-proET-1 to the base model had stronger prognostic power (p<0.01 than adding NT-proBNP (p<0.01. Adding CT-proET-1 to NT-proBNP in this model yielded further prognostic information (p = 0.02. CONCLUSIONS: Plasma CT-proET-1 constitutes a novel predictor of increased 12-month cardiovascular mortality in patients with CHF. High CT-proET-1 together with high NT-proBNP enable to identify patients with CHF and particularly unfavourable outcomes.

The Role of Endothelin System in Renal Structure and Function during the Postnatal Development of the Rat Kidney.

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Albertoni Borghese, María F; Ortiz, María C; Balonga, Sabrina; Moreira Szokalo, Rocío; Majowicz, Mónica P

2016-01-01

Renal development in rodents, unlike in humans, continues during early postnatal period. We aimed to evaluate whether the pharmacological inhibition of Endothelin system during this period affects renal development, both at structural and functional level in male and female rats. Newborn rats were treated orally from postnatal day 1 to 20 with vehicle or bosentan (Actelion, 20 mg/kg/day), a dual endothelin receptor antagonist (ERA). The animals were divided in 4 groups: control males, control females, ERA males and ERA females. At day 21, we evaluated renal function, determined the glomerular number by a maceration method and by morphometric analysis and evaluated possible structural renal alterations by three methods: 〈alpha〉-Smooth muscle actin (α-SMA) immunohistochemistry, Masson's trichrome and Sirius red staining. The pharmacological inhibition of Endothelin system with a dual ERA during the early postnatal period of the rat did not leads to renal damage in the kidneys of male and female rats. However, ERA administration decreased the number of glomeruli, the juxtamedullary filtration surface area and the glomerular filtration rate and increased the proteinuria. These effects could predispose to hypertension or renal diseases in the adulthood. On the other hand, these effects were more pronounced in male rats, suggesting that there are sex differences that could be greater later in life. These results provide evidence that Endothelin has an important role in rat renal postnatal development. However these results do not imply that the same could happen in humans, since human renal development is complete at birth.

Protective effect of glycyrrhizin, a direct HMGB1 inhibitor, on focal cerebral ischemia/reperfusion-induced inflammation, oxidative stress, and apoptosis in rats.

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Gu Gong

Full Text Available AIM: Glycyrrhizin (GL has been reported to protect against ischemia and reperfusion (I/R-induced injury by inhibiting the cytokine activity of high mobility group box 1 (HMGB1. In the present study, the protective effects of GL against I/R injury, as well as the related molecular mechanisms, were investigated in rat brains. METHODS: Focal cerebral I/R injury was induced by intraluminal filamentous occlusion of the middle cerebral artery (MCA in Male Sprague-Dawley rats. GL alone or GL and rHMGB1 were administered intravenously at the time of reperfusion. Serum levels of HMGB1 and inflammatory mediators were quantified via enzyme-linked immunosorbent assay (ELISA. Histopathological examination, immunofluorescence, RT-PCR and western blotting analyses were performed to investigate the protective and anti-apoptotic effects and related molecular mechanisms of GL against I/R injury in rat brains. RESULTS: Pre-treatment with GL significantly reduced infarct volume and improved the accompanying neurological deficits in locomotor function. The release of HMGB1 from the cerebral cortex into the serum was inhibited by GL administration. Moreover, pre-treatment with GL alleviated apoptotic injury resulting from cerebral I/R through the inhibition of cytochrome C release and caspase 3 activity. The expression levels of inflammation- and oxidative stress-related molecules including TNF-α, iNOS, IL-1β, and IL-6, which were over-expressed in I/R, were decreased by GL. P38 and P-JNK signalling were involved in this process. All of the protective effects of GL could be reversed by rHMGB1 administration. CONCLUSIONS: GL has a protective effect on ischemia-reperfusion injury in rat brains through the inhibition of inflammation, oxidative stress and apoptotic injury by antagonising the cytokine activity of HMGB1.

Plasma level of endothelin, 6-keto-PGF1α and urine albumin in essential hypertension with diabetes mellitus and their significance

International Nuclear Information System (INIS)

Miao Datong

2001-01-01

Objective: To investigate the damage of blood vessel endothelium and kidney function in patients with essential hypertension plus diabetes mellitus. Methods: Plasma levels of endothelin (Et) and 6-keto-PGF 1α (6-K-PGF 1α ) as well as urine albumin content were measured by radio immunoassay in 75 patients with essential hypertension (EH), among them 34 were complicated with DM, 35 controls were included in this experiment. Results: The plasma level of ET, 6-K-PGF 1α and urine Alb content were significantly higher in the patients than those in the controls (P 1α were also higher but of no statistic significance. Conclusion: The results suggest that the EH patients with DM were complicated with more serous damage in kidney function

Endothelin B receptors contribute to retinal ganglion cell loss in a rat model of glaucoma.

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Alena Z Minton

Full Text Available Glaucoma is an optic neuropathy, commonly associated with elevated intraocular pressure (IOP characterized by optic nerve degeneration, cupping of the optic disc, and loss of retinal ganglion cells which could lead to loss of vision. Endothelin-1 (ET-1 is a 21-amino acid vasoactive peptide that plays a key role in the pathogenesis of glaucoma; however, the receptors mediating these effects have not been defined. In the current study, endothelin B (ET(B receptor expression was assessed in vivo, in the Morrison's ocular hypertension model of glaucoma in rats. Elevation of IOP in Brown Norway rats produced increased expression of ET(B receptors in the retina, mainly in retinal ganglion cells (RGCs, nerve fiber layer (NFL, and also in the inner plexiform layer (IPL and inner nuclear layer (INL. To determine the role of ET(B receptors in neurodegeneration, Wistar-Kyoto wild type (WT and ET(B receptor-deficient (KO rats were subjected to retrograde labeling with Fluoro-Gold (FG, following which IOP was elevated in one eye while the contralateral eye served as control. IOP elevation for 4 weeks in WT rats caused an appreciable loss of RGCs, which was significantly attenuated in KO rats. In addition, degenerative changes in the optic nerve were greatly reduced in KO rats compared to those in WT rats. Taken together, elevated intraocular pressure mediated increase in ET(B receptor expression and its activation may contribute to a decrease in RGC survival as seen in glaucoma. These findings raise the possibility of using endothelin receptor antagonists as neuroprotective agents for the treatment of glaucoma.

Increased endothelin-1 and diminished nitric oxide levels in blister fluids of patients with intermediate cold type complex regional pain syndrome type 1

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Niehof Sjoerd

2006-11-01

Full Text Available Abstract Background In complex regional pain syndrome type 1 (CRPS1 pro-inflammatory mediators and vascular changes play an important role in the sustained development and outcome of the disease. The aim of this study was to determine the involvement of vasoactive substances endothelin-1 (ET-1 and nitric oxide (NO during early chronic CRPS1. Methods Included were 29 patients with CRPS 1 who were diagnosed during the acute stage of their disease and observed during follow-up visits. Disease activity and impairment were determined and artificial suction blisters were made on the CRPS1 and the contralateral extremities for measurements of IL-6, TNF-α, ET-1 and nitrate/nitrite (NOx. Results The levels of IL-6, TNF-α and ET-1 in blister fluid in the CRPS1 extremity versus the contralateral extremity were significantly increased and correlated with each other, whereas NOx levels were decreased. Conclusion The NOx/ET-1 ratio appears to be disturbed in the intermediate stage of CRPS, resulting in vasoconstriction and consequently in a diminished tissue blood distribution.

Dual neural endopeptidase/endothelin-converting [corrected] enzyme inhibition improves endothelial function in mesenteric resistance arteries of young spontaneously hypertensive rats

DEFF Research Database (Denmark)

Lemkens, Pieter; Nelissen, Jelly; Meens, Merlijn J P M T

2012-01-01

BACKGROUND: Endothelin-1 (ET1) is a potent vasoconstrictor peptide with pro-mitogenic and pro-inflammatory properties and is therefore of interest in the development of endothelial dysfunction, endothelium-dependent flow-related remodeling, and hypertension-related remodeling. ET1 can be formed t...

Effective prophylaxis of visual and neurological disturbances with an anti-endothelin drug: analysis of 1642 sclerotherapy sessions

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Alessandro Frullini

2016-12-01

Full Text Available In the literature cases of stroke and transient neurological symptoms have been described after sclerotherapy for chronic venous disease The initial interpretation of these phenomena was that of a micro air embolism in association with a patent foramen ovale. This explanation did not always manage to justify all neurological manifestations. Recent theories have demonstrated that in the area of sclerosis, a significant amount of endothelin 1. We carried out a retrospective assessment of sclerotherapy case studies on 540 patients at ten phlebological centres to search for a relationship between the use of aminaftone (a venotropic drug with demonstrated anti-endothelin action and the occurrence of side effects after sclerotherapy was performed. Significant reduction of side effects was observed in sclerotherapy for teleangectasias and in patients with migraine history.

Focal lesions in the central nervous system

International Nuclear Information System (INIS)

Fabrikant, J.I.; Budinger, T.F.; Tobias, C.A.; Born, J.L.

1980-01-01

This report reviews the animal and human studies currently in progress at LBL with heavy-ion beams to induce focal lesions in the central nervous system, and discusses the potential future prospects of fundamental and applied brain research with heavy-ion beams. Methods are being developed for producing discrete focal lesions in the central nervous system using the Bragg ionization peak to investigate nerve pathways and neuroendocrine responses, and for treating pathological disorders of the brain

Mutations in KCNT1 cause a spectrum of focal epilepsies

DEFF Research Database (Denmark)

Møller, Rikke Steensbjerre; Heron, Sarah E.; Larsen, Line H. G.

2015-01-01

Autosomal dominant mutations in the sodium-gated potassium channel subunit gene KCNT1 have been associated with two distinct seizure syndromes, nocturnal frontal lobe epilepsy (NFLE) and malignant migrating focal seizures of infancy (MMFSI). To further explore the phenotypic spectrum associated w...

Comparative studies of vertebrate endothelin-converting enzyme-like 1 genes and proteins

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Holmes RS

2013-01-01

Full Text Available Roger S Holmes,1,2 Laura A Cox11Department of Genetics and Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA; 2Eskitis Institute for Cell and Molecular Therapies and School of Biomolecular and Physical Sciences, Griffith University, Nathan, Queensland, AustraliaAbstract: Endothelin-converting enzyme-like 1 (ECEL1 is a member of the M13 family of neutral endopeptidases which play an essential role in the neural regulation of vertebrate respiration. Genetic deficiency of this protein results in respiratory failure soon after birth. Comparative ECEL1 amino acid sequences and structures and ECEL1 gene locations were examined using data from several vertebrate genome projects. Vertebrate ECEL1 sequences shared 66%–99% identity as compared with 30%–63% sequence identities with other M13-like family members, ECE1, ECE2, and NEP (neprilysin or MME. Three N-glycosylation sites were conserved among most vertebrate ECEL1 proteins examined. Sequence alignments, conserved key amino acid residues, and predicted secondary and tertiary structures were also studied, including cytoplasmic, transmembrane, and luminal sequences and active site residues. Vertebrate ECEL1 genes usually contained 18 exons and 17 coding exons on the negative strand. Exons 1 and 2 of the human ECEL1 gene contained 5'-untranslated (5'-UTR regions, a large CpG island (CpG256, and several transcription factor binding sites which may contribute to the high levels of gene expression previously reported in neural tissues. Phylogenetic analyses examined the relationships and potential evolutionary origins of the vertebrate ECEL1 gene with six other vertebrate neutral endopeptidase M13 family genes. These suggested that ECEL1 originated in an ancestral vertebrate genome from a duplication event in an ancestral neutral endopeptidase M13-like gene.Keywords: vertebrates, amino acid sequence, ECEL1, ECE1, ECE2, KELL, NEP, NEPL1, PHEX

A 1.3 giga pixels focal plane for GAIA

Science.gov (United States)

Laborie, Anouk; Pouny, Pierre; Vetel, Cyril; Collados, Emmanuel; Rougier, Gilles; Davancens, Robert; Zayer, Igor; Perryman, Michael; Pace, Oscar

2004-06-01

The astrometric mission GAIA is a cornerstone mission of the European Space Agency, due for launch in the 2010 time frame. Requiring extremely demanding performance GAIA calls for the development of an unprecedented large focal plane featuring innovative technologies. For securing the very challenging GAIA development, a significant number of technology activities have been initiated by ESA through a competitive selection process. In this context, an industrial consortium led by EADS-Astrium (France) with e2v technologies (UK) as major subcontractor was selected for the GAIA CCD and Focal Plane Technology Demonstrators programme, which is by far the most significant and the most critical GAIA pre-development for all aspects: science performance, development schedule and cost. This programme has started since August 2002 and will end early 2005 prior to commencement of the GAIA Phase B. While the GAIA payload will host three instruments and related focal planes, the major mission objectives are assigned to the Astrometric (ASTRO) Focal Plane, which is the subject of this presentation.

Rac1 modulates G-protein-coupled receptor-induced bronchial smooth muscle contraction.

Science.gov (United States)

Sakai, Hiroyasu; Kai, Yuki; Sato, Ken; Ikebe, Mitsuo; Chiba, Yohihiko

2018-01-05

Increasing evidence suggests a functional role of RhoA/Rho-kinase signalling as a mechanism for smooth muscle contraction; however, little is known regarding the roles of Rac1 and other members of the Rho protein family. This study aimed to examine whether Rac1 modulates bronchial smooth muscle contraction. Ring preparations of bronchi isolated from rats were suspended in an organ bath, and isometric contraction of circular smooth muscle was measured. Immunoblotting was used to examine myosin light chain phosphorylation in bronchial smooth muscle. Our results demonstrated that muscle contractions induced by carbachol (CCh) and endothelin-1 (ET-1) were inhibited by EHT1864, a selective Rac1 inhibitor, and NSC23766, a selective inhibitor of Rac1-specific guanine nucleotide exchange factors. Similarly, myosin light chain and myosin phosphatase target subunit 1 (MYPT1) at Thr853 phosphorylation induced by contractile agonist were inhibited with Rac1 inhibition. However, contractions induced by high K + , calyculin A (a potent protein phosphatase inhibitor) and K + /PDBu were not inhibited by these Rac1 inhibitors. Interestingly, NaF (a G-protein activator)-induced contractions were inhibited by EHT1864 but not by NSC23766. We next examined the effects of a trans-acting activator of transcription protein transduction domain (PTD) fusion protein with Rac1 (PTD-Rac1) on muscle contraction. The constitutively active form of PTD-Rac1 directly induced force development and contractions were abolished by EHT1864. These results suggest that Rac1, activated by G protein-coupled receptor agonists, such as CCh and ET-1, may induce myosin light chain and MYPT phosphorylation and modulate the contraction of bronchial smooth muscle. Copyright © 2017 Elsevier B.V. All rights reserved.

Upregulation of contractile endothelin type B receptors by lipid-soluble cigarette smoking particles in rat cerebral arteries via activation of MAPK

International Nuclear Information System (INIS)

Sandhu, Hardip; Xu, Cang Bao; Edvinsson, Lars

2010-01-01

Cigarette smoke exposure increases the risk of stroke. However, the underlying molecular mechanisms are poorly understood. Endothelin system plays key roles in the pathogenesis of stroke. The present study was designed to examine if lipid-soluble (dimethyl sulfoxide-soluble) cigarette smoke particles (DSP) induces upregulation of contractile endothelin type B (ET B ) receptors in rat cerebral arteries and if activation of mitogen activated protein kinase (MAPK) and nuclear factor-kappaB (NF-κB) mediate the upregulation of contractile endothelin receptors in the cerebral arteries. Rat middle cerebral arteries were isolated and organ cultured in serum free medium for 24 h in the presence of DSP with or without specific inhibitors: MEK specific (U0126), p38 specific (SB202190), JNK specific (SP600125), NF-κB specific (BMS-345541) or (IMD-0354), transcription inhibitor (actinomycin D), or translation blocker (cycloheximide). Contractile responses to the ET B receptor agonist sarafotoxin 6c were investigated by a sensitive myograph. The expression of the ET B receptors were studied at mRNA and protein levels using quantitative real time PCR and immunohistochemistry, respectively. Results show that organ culture per se induced transcriptional upregulation of contractile ET B receptors in the cerebral vascular smooth muscle cells. This upregulation was further increased at the translational level by addition of DSP to the organ culture, but this increase was not seen by addition of nicotine or water-soluble cigarette smoke particles to the organ culture. The increased upregulation of contractile ET B receptors by DSP was abrogated by U0126, SP600125, actinomycin D, and cycloheximide, suggesting that the underlying molecular mechanisms involved in this process include activation of MEK and JNK MAPK-mediated transcription and translation of new contractile ET B receptors. Thus, the MAPK-mediated upregulation of contractile ET B receptors in cerebral arteries might be a

Focal adhesion kinase (FAK1 regulates SHB phosphorylation and its binding with a range of signaling proteins

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Dergai O. V.

2016-02-01

Full Text Available Aim. To investigate an effect of the Focal adhesion kinase 1 (FAK1 expression on the level of tyrosine phosphorylation of an adaptor protein SHB and to find functional consequences of this posttranslational modification. Methods. Recombinant DNA construction, protein expression and purification, human cell transfection, western blot. Results. The expression of FAK1 induces the massive tyrosine phosphorylation of SHB adaptor and enhances its interaction in vitro with SH2 domains of a range of the signaling proteins such as PI3K, ABL, CRK and PLCG1. Additionally we have found that Epstein-Barr virus protein LMP2A can partially mimic the FAK1-mediated effect strongly elevating the efficiency and SHB interaction with the mentioned above proteins. While the expression of individual proteins elevated SHB phosphorylation level, the co-expression of LMP2A and FAK1 did not display a synergetic effect. Conclusions. FAK1 as well as LMP2A induce the SHB tyrosine phosphorylation and enhance its interaction with a set of the signaling proteins.

Endothelin B receptor blockade attenuates pulmonary vasodilation in oxygen-ventilated fetal lambs.

Science.gov (United States)

Ivy, D Dunbar; Lee, Dong-Seok; Rairigh, Robyn L; Parker, Thomas A; Abman, Steven H

2004-01-01

Endothelin-1 (ET-1) contributes to the regulation of pulmonary vascular tone in the normal ovine fetus and in models of perinatal pulmonary hypertension. In the fetal lamb lung, the effects of ET-1 depend on the balance of at least two endothelin receptor subtypes: ETA and ETB. ETA receptors are located on smooth muscle cells and mediate vasoconstriction and smooth muscle proliferation. Stimulation of endothelial ETB receptors causes vasodilation through release of nitric oxide and also functions to remove ET-1 from the circulation. However, whether activation of ETB receptors contributes to the fall in pulmonary vascular tone at birth is unknown. To determine the role of acute ETB receptor blockade in pulmonary vasodilation in response to birth-related stimuli, we studied the hemodynamic effects of selective ETB receptor blockade with BQ-788 during mechanical ventilation with low (<10%) and high FiO2 (100%) in near-term fetal sheep. Intrapulmonary infusion of BQ-788 did not change left pulmonary artery (LPA) blood flow and pulmonary vascular resistance (PVR) at baseline. In comparison with controls, BQ-788 treatment attenuated the rise in LPA flow with low and high FiO2 ventilation (p <0.001 vs. control for each FiO2 concentration). PVR progressively decreased during mechanical ventilation with low and high FiO2 in both groups, but PVR remained higher after BQ-788 treatment throughout the study period (p <0.001). We conclude that selective ETB receptor blockade attenuates pulmonary vasodilation at birth. We speculate that ETB receptor stimulation contributes to pulmonary vasodilation at birth in the ovine fetus.

Isosorbide 5 mononitrate administration increases nitric oxide blood levels and reduces proteinuria in IgA glomerulonephritis patients with abnormal urinary endothelin/cyclic GMP ratio.

Science.gov (United States)

Roccatello, D; Mengozzi, G; Ferro, M; Cesano, G; Polloni, R; Mosso, R; Bonetti, G; Inconis, T; Paradisi, L; Sena, L M

1995-09-01

An endothelin urinary hyperexcretion, which is not counterbalanced by an adequate increase in cGMP biosynthesis, was previously detected in some patients with IgA Nephropathy (IgAN). Since this imbalance might potentiate local ET1-mediated hemodynamics effects, 9 IgAN patients with an increased (> or = 0.1) urinary ET1/cGMP ratio (group 1) and 5 IgAN patients with comparable renal function and reduced ET1/cGMP ratio (group 2) were given standard doses of isosorbide 5 mononitrate (as a nitric oxide source). Blood nitric oxide (NO) levels, as detected by electron paramagnetic resonance, significantly increased after isosorbide administration (p effective renal plasma flow (p counterbalancing effects of nitric oxide on endothelin-mediated mesangial contraction.

Dual-layer electrode-driven liquid crystal lens with electrically tunable focal length and focal plane

Science.gov (United States)

Zhang, Y. A.; Lin, C. F.; Lin, J. P.; Zeng, X. Y.; Yan, Q.; Zhou, X. T.; Guo, T. L.

2018-04-01

Electric-field-driven liquid crystal (ELC) lens with tunable focal length and their depth of field has been extensively applied in 3D display and imaging systems. In this work, a dual-layer electrode-driven liquid crystal (DELC) lens with electrically tunable focal length and controllable focal plane is demonstrated. ITO-SiO2-AZO electrodes with the dual-layer staggered structure on the top substrate are used as driven electrodes within a LC cell, which permits the establishment of an alternative controllability. The focal length of the DELC lens can be adjusted from 1.41 cm to 0.29 cm when the operating voltage changes from 15 V to 40 V. Furthermore, the focal plane of the DELC lens can selectively move by changing the driving method of the applied voltage to the next driven electrodes. This work demonstrates that the DELC lens has potential applications in imaging systems because of electrically tunable focal length and controllable focal plane.

Hemopexin induces neuroprotection in the rat subjected to focal cerebral ischemia.

Science.gov (United States)

Dong, Beibei; Cai, Min; Fang, Zongping; Wei, Haidong; Zhu, Fangyun; Li, Guochao; Dong, Hailong; Xiong, Lize

2013-06-10

The plasma protein hemopexin (HPX) exhibits the highest binding affinity to free heme. In vitro experiments and gene-knock out technique have suggested that HPX may have a neuroprotective effect. However, the expression of HPX in the brain was not well elucidated and its expression after cerebral ischemia-reperfusion injury was also poorly studied. Furthermore, no in vivo data were available on the effect of HPX given centrally on the prognosis of focal cerebral ischemia. In the present study, we systematically investigated expression of HPX in normal rat brain by immunofluorescent staining. The results showed that HPX was mainly expressed in vascular system and neurons, as well as in a small portion of astrocytes adjacent to the vessels in normal rat brain. Further, we determined the role of HPX in the process of focal cerebral ischemic injury and explored the effects of HPX treatment in a rat model of transient focal cerebral ischemia. After 2 h' middle cerebral artery occlusion (MCAO) followed by 24 h' reperfusion, the expression of HPX was increased in the neurons and astrocytes in the penumbra area, as demonstrated by immunohistochemistry and Western blot techniques. Intracerebroventricular injection of HPX at the onset of reperfusion dose-dependently reduced the infarct volumes and improved measurements of neurological function of the rat subjected to transient focal cerebral ischemia. The neuroprotective effects of HPX sustained for up to 7 days after experiments. Our study provides a new insight into the potential neuroprotective role of HPX as a contributing factor of endogenous protective mechanisms against focal cerebral ischemia injury, and HPX might be developed as a potential agent for treatment of ischemic stroke.

NO and prostanoids blunt endothelin-mediated coronary vasoconstrictor influence in exercising swine

NARCIS (Netherlands)

D. Merkus (Daphne); O. Sorop (Oana); B. Houweling (Birgit); F. Boomsma (Frans); A.H. van den Meiracker (Anton); D.J.G.M. Duncker (Dirk)

2006-01-01

textabstractWithdrawal of the endothelin (ET)-mediated vasoconstrictor influence contributes to metabolic coronary vasodilation during exercise. Because production of nitric oxide (NO) and prostanoids increases with increasing shear stress and because NO and prostanoids are able to modify the

A feed-forward regulation of endothelin receptors by c-Jun in human non-pigmented ciliary epithelial cells and retinal ganglion cells.

Directory of Open Access Journals (Sweden)

Junming Wang

Full Text Available c-Jun, c-Jun N-terminal kinase(JNK and endothelin B (ETB receptor have been shown to contribute to the pathogenesis of glaucoma. Previously, we reported that an increase of c-Jun and CCAAT/enhancer binding protein β (C/EBPβ immunohistostaining is associated with upregulation of the ETB receptor within the ganglion cell layer of rats with elevated intraocular pressure (IOP. In addition, both transcription factors regulate the expression of the ETB receptor in human non-pigmented ciliary epithelial cells (HNPE. The current study addressed the mechanisms by which ET-1 produced upregulation of ET receptors in primary rat retinal ganglion cells (RGCs and HNPE cells. Treatment of ET-1 and ET-3 increased the immunocytochemical staining of c-Jun and C/EBPβ in primary rat RGCs and co-localization of both transcription factors was observed. A marked increase in DNA binding activity of AP-1 and C/EBPβ as well as elevated protein levels of c-Jun and c-Jun-N-terminal kinase (JNK were detected following ET-1 treatment in HNPE cells. Overexpression of ETA or ETB receptor promoted the upregulation of c-Jun and also elevated its promoter activity. In addition, upregulation of C/EBPβ augmented DNA binding and mRNA expression of c-Jun, and furthermore, the interaction of c-Jun and C/EBPβ was confirmed using co-immunoprecipitation. Apoptosis of HNPE cells was identified following ET-1 treatment, and overexpression of the ETA or ETB receptor produced enhanced apoptosis. ET-1 mediated upregulation of c-Jun and C/EBPβ and their interaction may represent a novel mechanism contributing to the regulation of endothelin receptor expression. Reciprocally, c-Jun was also found to regulate the ET receptors and C/EBPβ appeared to play a regulatory role in promoting expression of c-Jun. Taken together, the data suggests that ET-1 triggers the upregulation of c-Jun through both ETA and ETB receptors, and conversely c-Jun also upregulates endothelin receptor expression

Clinical significance of incidental focal "1"8F-FDG uptake in the spinal cord of patients with cancer

International Nuclear Information System (INIS)

Lim, Chae Hong; Hyun, Seung Hyup; Moon, Seung Hwan; Cho, Young Seok; Choe, Yearn Seong; Lee, Kyung Han; Kim, Byung Tae; Choi, Joon Young

2017-01-01

We investigated the incidence, location, and clinical significance of focal "1"8F-FDG uptake of the spinal cord in patients with cancer. We reviewed the medical records of 22,937 consecutive adult patients with known or suspicious malignancy who underwent "1"8F-FDG PET/CT. PET/CT scans with incidental focal spinal cord uptake were selected and retrospectively reviewed to determine the presence, location, number, and maximum standardized uptake value (SUV_m_a_x) of any focal hypermetabolic lesions of the spinal cord. In subjects with focal spinal uptake, clinical characteristics and clinical follow-up results, including follow-up PET/CT, were reviewed. Incidental focal spinal cord uptake was observed in 69 of 22,937 adult patients (incidence = 0.3%; M:F = 31:38; age, 55.8 ± 14.7 years). Seventy-eight focal hypermetabolic lesions on spinal cord in the PET/CT scans of the 69 study subjects were analyzed. The most common sites of focal spinal cord uptake were the T12 vertebra (47/78; 60.3%) and L1 vertebra (20/78; 25.6%). Multifocal cord uptake was found in 8 of 69 patients (11.6%). The average SUVmax for cord uptake was 2.5 ± 0.5 (range, 1.4∼3.9). There was no clinical or imaging evidence of abnormalities in the spinal cord, both at the time of PET/CT and during clinical follow-up. Although incidental focal "1"8F-FDG uptake of the spinal cord is rare in patients with cancer, it may be physiological or benign, but it should not be considered as malignant involvement. Common sites for the uptake were in the T12 and L1 spine levels

An ionization-chamber type of focal-plane detector for heavy ions

International Nuclear Information System (INIS)

Erskine, J.R.; Braid, T.H.; Stolfzfus, J.C.

1976-01-01

A focal-plane detector for heavy ions is described in which energy loss and total energy are measured with a gridded ionization chamber, and position along the focal plane and angle of incidence are measured with two resistive-wire proportional counters. The clean geometry of the detector makes it especially attractive for use with heavy ions of high specific ionization. Typical position resolutions of 1.0-1.5mm (fwhm) were observed over a 50 cm length of the detector in the focal plane of a split-pole magnetic spectrograph. Special tests were made which suggest that the limiting position resolution is 0.76 mm or better. The resolution of the energy-loss signal was typically 4.5% (fwhm). The resolution of the total energy signal was 1.0-1.5% (fwhm) for small entrance apertures of the spectrograph, although 0.7% resolution was observed under special circumstances. The angle of incidence was measured with an uncertainty of about 1.2% (fwhm). The availability of the many parameters needed for particle identification makes this detector especially useful for the study of weak reaction channels in heavy-ion-induced reactions. (Auth.)

Correlation of plasma endothelin-1 levels with pulmonary hypertension after inhaled nitric oxide therapy

International Nuclear Information System (INIS)

Razzaq, Z.; Naqvi, S.; Aslam, M.

2009-01-01

Variable response to inhaled nitric oxide (iNO) therapy in patients with mitral stenosis (MS) having pulmonary hypertension (PH) has been documented in early studies. The objectives of this study were to measure plasma Endothelin-1 (ET-1) levels in those patients and to correlate them with pulmonary vascular indices after iNO therapy. It was Quesi-experimental study. Methods: Thirty patients with mitral or mixed mitral and aortic valve disease with severe pulmonary hypertension and enrolled for valve replacement surgery were included. Before the replacement, baseline pulmonary vascular indices and cardiac output were recorded. After the surgery, 10 - 20 was in administered for 1 hour and all the parameters were again recorded. Patients were grouped into responders and non responders on the basis of % reduction in Pulmonary Vascular Resistance (PVR) after iNO therapy. Plasma ET-1 levels were measured in both groups by ELISA before and after the iNO therapy. Paired sample t-test was used to compare mean values for significance. The correlations between variables were then calculated by using Pearson's coefficient. Results: The plasma ET-1 levels were very high in all patients. They reduced in responders after iNO therapy; non-responders paradoxically showed significant increase in the levels of ET-1 after iNO therapy. Moreover, a positive correlation was observed in plasma ET-1 levels and post operative levels of PVR. Conclusion: The correlation of changes in PVR and plasma ET-1 levels in responders suggests that high plasma ET-1 is a key mediator of poor response in PH secondary to MS, after iNO therapy. (author)

High cut-off haemodialysis induces remission of recurrent idiopathic focal segmental glomerulosclerosis after renal transplantation but is no alternative to plasmapheresis

NARCIS (Netherlands)

I. Noorlander (Iris); D.A. Hesselink (Dennis); M. Wabbijn (Marike); M.G.H. Betjes (Michiel)

2011-01-01

textabstractA 26-year-old male experienced a recurrence of idiopathic focal segmental glomerulosclerosis (iFSGS) after his second renal transplant. Reduction of proteinuria was rapidly induced by plasmapheresis (PP) and the patient has remained in remission with a once-weekly PP regimen, which has

Functional heterogeneity of NADPH oxidase-mediated contractions to endothelin with vascular aging.

Science.gov (United States)

Meyer, Matthias R; Barton, Matthias; Prossnitz, Eric R

2014-11-24

Aging, a physiological process and main risk factor for cardiovascular and renal diseases, is associated with endothelial cell dysfunction partly resulting from NADPH oxidase-dependent oxidative stress. Because increased formation of endothelium-derived endothelin-1 (ET-1) may contribute to vascular aging, we studied the role of NADPH oxidase function in age-dependent contractions to ET-1. Renal arteries and abdominal aortas from young and old C57BL6 mice (4 and 24 months of age) were prepared for isometric force measurements. Contractions to ET-1 (0.1-100 nmol/L) were determined in the presence and absence of the NADPH oxidase-selective inhibitor gp91ds-tat (3 μmol/L). To exclude age-dependent differential effects of NO bioactivity between vascular beds, all experiments were conducted in the presence of the NO synthase inhibitor L-NAME (300 μmol/L). In young animals, ET-1-induced contractions were 6-fold stronger in the renal artery than in the aorta (prenal artery and aorta, respectively (pAging had no effect on NADPH oxidase-dependent and -independent contractions to ET-1 in the renal artery. In contrast, contractions to ET-1 were markedly reduced in the aged aorta (5-fold, page-dependent heterogeneity of NADPH oxidase-mediated vascular contractions to ET-1, demonstrating an inherent resistance to functional changes in the renal artery but not in the aorta with aging. Thus, local activity of NADPH oxidase differentially modulates responses to ET-1 with aging in distinct vascular beds. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Current pathophysiological views on vibration-induced Raynaud's phenomenon.

Science.gov (United States)

Stoyneva, Z; Lyapina, M; Tzvetkov, D; Vodenicharov, E

2003-03-01

This review attempts to summarize and discuss contemporary pathogenetic views on vibration-induced Raynaud's phenomenon assuming its multifactorial etiology. An increase in central and peripheral sympathetic nervous activity is discussed based on different physiological indicators of autonomic dysfunction and sympathetic hyperactivity. Local acral vasodysregulation is considered. Receptor and nerve endings dysfunction presented with predominance of alpha(2)-receptor function in the digital arteries and neuronal loss in those digital cutaneous perivascular nerves containing calcitonin gene-related peptide result in deficiency of endogenous release of this powerful vasodilator. Endothelial damage and dysregulation induced by vibration and increased shear stresses are demonstrated by the elevated plasma level of thrombomodulin and of von Willebrand factor and reduced endothelium-dependent vasodilator responses. The concentrations of endothelin-1 are high, the highest being in most advanced stages. Decreased plasma thiol level, indicating increased production and activity of free radicals, contribute to vasospastic paroxysms in vibration white finger patients. Dysbalance of local vasoactive factors with opposing effects on vascular smooth muscle like endothelin and nitric oxide, endothelin and calcitonin gene-related peptide, nitric oxide and superoxide anion are discussed. Disturbed smooth muscle response is supposed. Changes in hemostasis, fibrinolysis and hemorrheology, activation of blood cells with erythrocyte hyperaggregation and red cell hypodeformability, platelet aggregation with increased release of vasoconstricting thromboxane A(2) and serotonin as well as leukocyte activation, entrapment within capillaries and post-capillary venules and increased reactive oxygen species and lysosomal lytic enzymes release might also contribute to digital vasospasms and tissue damage. Elevated soluble intercellular adhesion molecule-1 levels involved in the adherence of

Endothelin-1 stimulates catalase activity through the PKCδ mediated phosphorylation of Serine 167

Science.gov (United States)

Rafikov, Ruslan; Kumar, Sanjiv; Aggarwal, Saurabh; Hou, Yali; Kangath, Archana; Pardo, Daniel; Fineman, Jeffrey R.; Black, Stephen M.

2013-01-01

Our previous studies have shown that endothelin-1 (ET-1) stimulates catalase activity in endothelial cells and lambs with acute increases in pulmonary blood flow (PBF), without altering gene expression. The purpose of this study was to investigate the molecular mechanism by which this occurs. Exposing pulmonary arterial endothelial cells (PAEC) to ET-1 increased catalase activity and decreased cellular hydrogen peroxide (H2O2) levels. These changes correlated with an increase in serine phosphorylated catalase. Using the inhibitory peptide δV1.1, this phosphorylation was shown to be PKCδ dependent. Mass spectrometry identified serine167 as the phosphorylation site. Site-directed mutagenesis was used to generate a phospho-mimic (S167D) catalase. Activity assays using recombinant protein purified from E.coli or transiently transfected COS-7 cells, demonstrated that S167D-catalase had an increased ability to degrade H2O2 compared to the wildtype enzyme. Using a phospho-specific antibody, we were able to verify that pS167 catalase levels are modulated in lambs with acute increases in PBF in the presence and absence of the ET receptor antagonist, tezosentan. S167 is being located on the dimeric interface suggesting it could be involved in regulating the formation of catalase tetramers. To evaluate this possibility we utilized analytical gel-filtration to examine the multimeric structure of recombinant wildtype- and S167D-catalase. We found that recombinant wildtype catalase was present as a mixture of monomers and dimers while S167D catalase was primarily tetrameric. Further, the incubation of wildtype catalase with PKCδ was sufficient to convert wildtype catalase into a tetrameric structure. In conclusion, this is the first report indicating that the phosphorylation of catalase regulates its multimeric structure and activity. PMID:24211614

Big endothelin changes the cellular miRNA environment in TMOb osteoblasts and increases mineralization.

Science.gov (United States)

Johnson, Michael G; Kristianto, Jasmin; Yuan, Baozhi; Konicke, Kathryn; Blank, Robert

2014-08-01

Endothelin (ET1) promotes the growth of osteoblastic breast and prostate cancer metastases. Conversion of big ET1 to mature ET1, catalyzed primarily by endothelin converting enzyme 1 (ECE1), is necessary for ET1's biological activity. We previously identified the Ece1, locus as a positional candidate gene for a pleiotropic quantitative trait locus affecting femoral size, shape, mineralization, and biomechanical performance. We exposed TMOb osteoblasts continuously to 25 ng/ml big ET1. Cells were grown for 6 days in growth medium and then switched to mineralization medium for an additional 15 days with or without big ET1, by which time the TMOb cells form mineralized nodules. We quantified mineralization by alizarin red staining and analyzed levels of miRNAs known to affect osteogenesis. Micro RNA 126-3p was identified by search as a potential regulator of sclerostin (SOST) translation. TMOb cells exposed to big ET1 showed greater mineralization than control cells. Big ET1 repressed miRNAs targeting transcripts of osteogenic proteins. Big ET1 increased expression of miRNAs that target transcripts of proteins that inhibit osteogenesis. Big ET1 increased expression of 126-3p 121-fold versus control. To begin to assess the effect of big ET1 on SOST production we analyzed both SOST transcription and protein production with and without the presence of big ET1 demonstrating that transcription and translation were uncoupled. Our data show that big ET1 signaling promotes mineralization. Moreover, the results suggest that big ET1's osteogenic effects are potentially mediated through changes in miRNA expression, a previously unrecognized big ET1 osteogenic mechanism.

Serial alterations in digital hemodynamics and endothelin-1 immunoreactivity, platelet-neutrophil aggregation, and concentrations of nitric oxide, insulin, and glucose in blood obtained from horses following carbohydrate overload.

Science.gov (United States)

Eades, Susan C; Stokes, Ashley M; Johnson, Philip J; LeBlanc, Casey J; Ganjam, Venkataseshu K; Buff, Preston R; Moore, Rustin M

2007-01-01

To quantify changes in endothelium-derived factors and relate those changes to various aspects of digital hemodynamics during the prodromal stages of carbohydrate overload (CHO)-induced laminitis in horses. 20 adult horses without abnormalities of the digit. Digital and jugular venous blood samples were collected at 1-hour intervals (for assessment of endothelin-1 [ET-1] immunoreactivity and measurement of glucose, insulin, and nitric oxide [NO] concentrations) or 4-hour intervals (CBC and platelet-neutrophil aggregate assessment) for 8 hours or 16 hours after induction of CHO-associated laminitis in horses treated with an ET-1 antagonist. Effects of treatment, collection site, and time and the random effects of horse on each variable were analyzed by use of a repeated-measures model. Where treatment and collection site had no significant effect, data were combined. Compared with baseline values, CHO resulted in changes in several variables, including a significant increase from baseline in digital blood ET-like immunoreactivity at 11 hours; digital blood ET-like immunoreactivity was significantly greater than that in jugular venous blood at 8, 9, 11, and 12 hours. Digital and jugular venous blood concentrations of glucose increased from baseline significantly at 3, 4, and 5 hours; insulin concentration increased significantly at 5 hours; and the number of platelet-neutrophil aggregates increased significantly at 12 hours. In horses, concurrent increases in venous blood ET-1 immunoreactivity, insulin and glucose concentrations, and platelet-neutrophil aggregates support a role of endothelial dysfunction in the pathogenesis of CHO-induced laminitis.

Ischemic hippocampal lesion leads to cognitive impairment and epileptogenesis in immature rats

Czech Academy of Sciences Publication Activity Database

Kubová, Hana; Máttéffyová, Adéla; Otáhal, Jakub; Mareš, Pavel

2005-01-01

Roč. 46, č. S6 (2005), s. 357-358 ISSN 0013-9580. [International Epilepsy Congress /26./. 28.08.2005-01.09.2005, Paris] Institutional research plan: CEZ:AV0Z50110509 Keywords : focal ischemia * endothelin-1 * epileptogenesis Subject RIV: ED - Physiology

Correlations between plasma endothelin-1 levels and breakthrough pain in patients with cancer

Directory of Open Access Journals (Sweden)

Yan XB

2015-12-01

Full Text Available Xue-bin Yan, Tuo-chao Peng, Dong Huang Department of Anesthesiologist, The Third Xiangya Hospital of Central South University, Changsha, Hunan Province, People’s Republic of China Abstract: Endothelin-1 (ET-1 may be involved in driving pain in patients with advanced cancer. However, a few studies focus on the role of ET-1 in breakthrough pain (BP. The aim of this pivotal study was to explore the correlation between the plasma (ET-1 level and BP intensity. A total of 40 patients were enrolled in the study, and they were divided into two groups: BP group and non-BP group. Moreover, 20 healthy adults were used as the normal control group. Pain intensity was measured using visual analog scale (VAS scores of 1–10. Plasma ET-1 levels were detected by an ET radioimmunoassay kit. Subsequently, the correlation of ET-1 level with the VAS score and cancer types was analyzed by Pearson’s correlation coefficient. The plasma ET-1 level in the BP group (35.31±8.02 pg/mL was higher than that in the non-BP group (29.51±6.78 pg/mL and the normal control group (24.77±10.10 pg/mL, P<0.05. In addition, the VAS score in the BP group (7.45±0.82 was higher than that in the non-BP group (2.80±1.23, P<0.05. The plasma ET-1 level was positively correlated with the VAS score of the BP group (Pearson’s r=0.42. There was no significant correlation between the plasma ET-1 level and VAS score of the non-BP group (Pearson’s r=–0.22 or/and cancer types (P>0.05. The elevated plasma ET-1 levels were positively related to BP, and targeting ET-1 may provide a novel pain-reducing therapeutic treatment in BP. Keywords: visual analog scale, correlation, cancer types, background pain

Involvement of α₂-adrenoceptors, imidazoline, and endothelin-A receptors in the effect of agmatine on morphine and oxycodone-induced hypothermia in mice.

Science.gov (United States)

Bhalla, Shaifali; Andurkar, Shridhar V; Gulati, Anil

2013-10-01

Potentiation of opioid analgesia by endothelin-A (ET(A)) receptor antagonist, BMS182874, and imidazoline receptor/α₂-adrenoceptor agonists such as clonidine and agmatine are well known. It is also known that agmatine blocks morphine hyperthermia in rats. However, the effect of agmatine on morphine or oxycodone hypothermia in mice is unknown. The present study was carried out to study the role of α₂-adrenoceptors, imidazoline, and ET(A) receptors in morphine and oxycodone hypothermia in mice. Body temperature was determined over 6 h in male Swiss Webster mice treated with morphine, oxycodone, agmatine, and combination of agmatine with morphine or oxycodone. Yohimbine, idazoxan, and BMS182874 were used to determine involvement of α₂-adrenoceptors, imidazoline, and ET(A) receptors, respectively. Morphine and oxycodone produced significant hypothermia that was not affected by α₂-adrenoceptor antagonist yohimbine, imidazoline receptor/α₂ adrenoceptor antagonist idazoxan, or ET(A) receptor antagonist, BMS182874. Agmatine did not produce hypothermia; however, it blocked oxycodone but not morphine-induced hypothermia. Agmatine-induced blockade of oxycodone hypothermia was inhibited by idazoxan and yohimbine. The blockade by idazoxan was more pronounced compared with yohimbine. Combined administration of BMS182874 and agmatine did not produce changes in body temperature in mice. However, when BMS182874 was administered along with agmatine and oxycodone, it blocked agmatine-induced reversal of oxycodone hypothermia. This is the first report demonstrating that agmatine does not affect morphine hypothermia in mice, but reverses oxycodone hypothermia. Imidazoline receptors and α₂-adrenoceptors are involved in agmatine-induced reversal of oxycodone hypothermia. Our findings also suggest that ET(A) receptors may be involved in blockade of oxycodone hypothermia by agmatine. © 2012 The Authors Fundamental and Clinical Pharmacology © 2012 Société Française de

TRIM15 is a focal adhesion protein that regulates focal adhesion disassembly

Science.gov (United States)

Uchil, Pradeep D.; Pawliczek, Tobias; Reynolds, Tracy D.; Ding, Siyuan; Hinz, Angelika; Munro, James B.; Huang, Fang; Floyd, Robert W.; Yang, Haitao; Hamilton, William L.; Bewersdorf, Joerg; Xiong, Yong; Calderwood, David A.; Mothes, Walther

2014-01-01

ABSTRACT Focal adhesions are macromolecular complexes that connect the actin cytoskeleton to the extracellular matrix. Dynamic turnover of focal adhesions is crucial for cell migration. Paxillin is a multi-adaptor protein that plays an important role in regulating focal adhesion dynamics. Here, we identify TRIM15, a member of the tripartite motif protein family, as a paxillin-interacting factor and a component of focal adhesions. TRIM15 localizes to focal contacts in a myosin-II-independent manner by an interaction between its coiled-coil domain and the LD2 motif of paxillin. Unlike other focal adhesion proteins, TRIM15 is a stable focal adhesion component with restricted mobility due to its ability to form oligomers. TRIM15-depleted cells display impaired cell migration and reduced focal adhesion disassembly rates, in addition to enlarged focal adhesions. Thus, our studies demonstrate a cellular function for TRIM15 as a regulatory component of focal adhesion turnover and cell migration. PMID:25015296

Neuroprotective effects of curcumin on endothelin-1 mediated cell death in hippocampal neurons.

Science.gov (United States)

Stankowska, Dorota L; Krishnamoorthy, Vignesh R; Ellis, Dorette Z; Krishnamoorthy, Raghu R

2017-06-01

Alzheimer's disease is a progressive neurodegenerative disease characterized by loss of hippocampal neurons leading to memory deficits and cognitive decline. Studies suggest that levels of the vasoactive peptide endothelin-1 (ET-1) are increased in the brain tissue of Alzheimer's patients. Curcumin, the main ingredient of the spice turmeric, has been shown to have anti-inflammatory, anti-cancer, and neuroprotective effects. However, the mechanisms underlying some of these beneficial effects are not completely understood. The objective of this study was to determine if curcumin could protect hippocampal neurons from ET-1 mediated cell death and examine the involvement of c-Jun in this pathway. Primary hippocampal neurons from rat pups were isolated using a previously published protocol. Viability of the cells was measured by the live/dead assay. Immunoblot and immunohistochemical analyses were performed to analyze c-Jun levels in hippocampal neurons treated with either ET-1 or a combination of ET-1 and curcumin. Apoptotic changes were evaluated by immunoblot detection of cleaved caspase-3, cleaved fodrin, and a caspase 3/7 activation assay. ET-1 treatment produced a 2-fold increase in the levels of c-Jun as determined by an immunoblot analysis in hippocampal neurons. Co-treatment with curcumin significantly attenuated the ET-1 mediated increase in c-Jun levels. ET-1 caused increased neuronal cell death of hippocampal neurons indicated by elevation of cleaved caspase-3, cleaved fodrin and an increased activity of caspases 3 and 7 which was attenuated by co-treatment with curcumin. Blockade of JNK, an upstream effector of c-Jun by specific inhibitor SP600125 did not fully protect from ET-1 mediated activation of pro-apoptotic enzymes in primary hippocampal cells. Our data suggests that one mechanism by which curcumin protects against ET-1-mediated cell death is through blocking an increase in c-Jun levels. Other possible mechanisms include decreasing pro

Inhibition on Apoptosis Induced by Elevated Hydrostatic Pressure in Retinal Ganglion Cell-5 via Laminin Upregulating β1-integrin/Focal Adhesion Kinase/Protein Kinase B Signaling Pathway.

Science.gov (United States)

Li, Yi; Chen, Yan-Ming; Sun, Ming-Ming; Guo, Xiao-Dan; Wang, Ya-Chen; Zhang, Zhong-Zhi

2016-04-20

Glaucoma is a progressive optic neuropathy characterized by degeneration of neurons due to loss of retinal ganglion cells (RGCs). High intraocular pressure (HIOP), the main risk factor, causes the optic nerve damage. However, the precise mechanism of HIOP-induced RGC death is not yet completely understood. This study was conducted to determine apoptosis of RGC-5 cells induced by elevated hydrostatic pressures, explore whether laminin is associated with apoptosis under pressure, whether laminin can protect RGCs from apoptosis and affirm the mechanism that regulates the process of RGCs survival. RGC-5 cells were exposed to 0, 20, 40, and 60 mmHg in a pressurized incubator for 6, 12, and 24 h, respectively. The effect of elevated hydrostatic pressure on RGC-5 cells was measured by Annexin V-fluorescein isothiocyanate/propidium iodide staining, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and Western blotting of cleaved caspase-3 protein. Location and expression of laminin were detected by immunofluorescence. The expression of β1-integrin, phosphorylation of focal adhesion kinase (FAK) and protein kinase B (PKB, or AKT) were investigated with real-time polymerase chain reaction and Western blotting analysis. Elevated hydrostatic pressure induced apoptosis in cultured RGC-5 cells. Pressure with 40 mmHg for 24 h induced a maximum apoptosis. Laminin was declined in RGC-5 cells after exposing to 40 mmHg for 24 h. After pretreating with laminin, RGC-5 cells survived from elevated pressure. Furthermore, β1-integrin and phosphorylation of FAK and AKT were increased compared to 40 mmHg group. The data show apoptosis tendency of RGC-5 cells with elevated hydrostatic pressure. Laminin can protect RGC-5 cells against high pressure via β1-integrin/FAK/AKT signaling pathway. These results suggest that the decreased laminin of RGC-5 cells might be responsible for apoptosis induced by elevated hydrostatic pressure, and laminin or activating β1-integrin

Achromatic Focal Plane Mask for Exoplanet Imaging Coronagraphy

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Newman, Kevin Edward; Belikov, Ruslan; Guyon, Olivier; Balasubramanian, Kunjithapatham; Wilson, Dan

2013-01-01

Recent advances in coronagraph technologies for exoplanet imaging have achieved contrasts close to 1e10 at 4 lambda/D and 1e-9 at 2 lambda/D in monochromatic light. A remaining technological challenge is to achieve high contrast in broadband light; a challenge that is largely limited by chromaticity of the focal plane mask. The size of a star image scales linearly with wavelength. Focal plane masks are typically the same size at all wavelengths, and must be sized for the longest wavelength in the observational band to avoid starlight leakage. However, this oversized mask blocks useful discovery space from the shorter wavelengths. We present here the design, development, and testing of an achromatic focal plane mask based on the concept of optical filtering by a diffractive optical element (DOE). The mask consists of an array of DOE cells, the combination of which functions as a wavelength filter with any desired amplitude and phase transmission. The effective size of the mask scales nearly linearly with wavelength, and allows significant improvement in the inner working angle of the coronagraph at shorter wavelengths. The design is applicable to almost any coronagraph configuration, and enables operation in a wider band of wavelengths than would otherwise be possible. We include initial results from a laboratory demonstration of the mask with the Phase Induced Amplitude Apodization coronagraph.

Circulating levels of endothelin-1 in a homogenous Gulf Arab population with untreated essential hypertension

International Nuclear Information System (INIS)

Obinache, C.N.; Abdullah, A.M.; Pathan, J.Y.; Bokahri, A.M.; Gillett, M.P.T.

2006-01-01

Rectal variations are reported in the natural history of high-tension. For example hypertension is significantly more prevalent in blacks than whites. Endothelial cells are important regulators of vasculars tone and homeostasis, in part through secretions of vasoactive substances including endothelin-I (ET-1), a small peptide with potent vaspressor actions in black hypertensive and normotensive whites. Since ET-I might play a significant role to the development and severity of hypertension in the indigenous Arab population of United Arab Emirates; we investigated the circulatory levels of ET-1 in the homogenous population. ET-I levels were measured in plasma samples from 60 unteated hypertensive Arabs and compared with 60 age and sex matched normotensive controls. ET-I levels were significantly higher in hypertensive (10.1+-pmol/L) than normtensives (mean 2.2+-0.5 pmol/L). Body mass index (BMI) was slightly higher among the hypertensive. For all subjects these levels significantly (P<0.001) correlated with systolic blood pressure and less significantly (P<0.05) with diastolic blood pressure and body weight. The correlation with ET-1 and both systolic and diastolic blood pressure with persistently significant after adjusting for BMI. Plasma concentration of ET-I are significantly higher in hypertensive Gulf Arabs as compared with reported levels in which hypertensives and ET-I could be a risk factor for cardiovascular diseases in this population. The endothelial sate might be particularly important with respect to hypertension in this racial group and merits further study. (author)

Magnaporthe oryzae Glycine-Rich Secretion Protein, Rbf1 Critically Participates in Pathogenicity through the Focal Formation of the Biotrophic Interfacial Complex.

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Takeshi Nishimura

2016-10-01

Full Text Available Magnaporthe oryzae, the fungus causing rice blast disease, should contend with host innate immunity to develop invasive hyphae (IH within living host cells. However, molecular strategies to establish the biotrophic interactions are largely unknown. Here, we report the biological function of a M. oryzae-specific gene, Required-for-Focal-BIC-Formation 1 (RBF1. RBF1 expression was induced in appressoria and IH only when the fungus was inoculated to living plant tissues. Long-term successive imaging of live cell fluorescence revealed that the expression of RBF1 was upregulated each time the fungus crossed a host cell wall. Like other symplastic effector proteins of the rice blast fungus, Rbf1 accumulated in the biotrophic interfacial complex (BIC and was translocated into the rice cytoplasm. RBF1-knockout mutants (Δrbf1 were severely deficient in their virulence to rice leaves, but were capable of proliferating in abscisic acid-treated or salicylic acid-deficient rice plants. In rice leaves, Δrbf1 inoculation caused necrosis and induced defense-related gene expression, which led to a higher level of diterpenoid phytoalexin accumulation than the wild-type fungus did. Δrbf1 showed unusual differentiation of IH and dispersal of the normally BIC-focused effectors around the short primary hypha and the first bulbous cell. In the Δrbf1-invaded cells, symplastic effectors were still translocated into rice cells but with a lower efficiency. These data indicate that RBF1 is a virulence gene essential for the focal BIC formation, which is critical for the rice blast fungus to suppress host immune responses.

Comparison of Serum Levels of Endothelin-1 in Chronic Periodontitis Patients Before and After Treatment

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Varghese, Sheeja S; Sankari, M.; Jayakumar, ND.

2017-01-01

Introduction Endothelin-1 (ET-1) is a potent vasoconstrictive peptide with multi functional activity in various systemic diseases. Previous studies indicate the detection of ET-1 in gingival tissues and gingival crevicular fluid. Aim The aim of this study was to estimate the serum ET-1 levels in clinically healthy subjects and subjects with chronic periodontitis, before and after treatment, and correlate it with the clinical parameters. Materials and Methods A total of 44 patients were included in the study. Group I comprised of 20 subjects with clinically healthy periodontium. Group II comprised of 24 subjects with chronic periodontitis. Group III comprised of same Group II subjects following periodontal management. Serum samples were collected from the subjects and an Enzyme Linked Immunosorbent Assay (ELISA) was done to estimate the ET-1 levels. The ET-1 levels were then correlated among the three groups with the clinical parameters namely, Plaque Index (PI), Sulcus Bleeding Index (SBI), probing pocket depth, clinical attachment loss and Periodontally Inflamed Surface Area (PISA). The independent t-test and paired t-test were used for comparison of clinical parameters and Pearson’s correlation coefficient test was used for correlating the ET-1 levels. Results ET-1 levels in chronic periodontitis subjects were significantly higher compared to healthy subjects (p<0.001). However, the clinical parameters did not statistically correlate with the ET-1 levels. There was a significant decrease in ET-1 levels following treatment (p<0.001). Conclusion Serum ET-1 is increased in chronic periodontitis and reduces after periodontal therapy. Further studies are required to establish ET-1 as a biomarker for periodontal disease. PMID:28571268

Pancreatic acini possess endothelin receptors whose internalization is regulated by PLC-activating agents.

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Hildebrand, P; Mrozinski, J E; Mantey, S A; Patto, R J; Jensen, R T

1993-05-01

Endothelin-1 (ET-1) and ET-3 mRNA have been found in the pancreas. We investigated the ability of ET-1, ET-2, and ET-3 to interact with and alter dispersed rat pancreatic acinar cell function. Radiolabeled ETs bound in a time- and temperature-dependent fashion, which was specific and saturable. Analysis demonstrated two classes of receptors, one class (ETA receptor) had a high affinity for ET-1 but a low affinity for ET-3, and the other class (ETB receptor) had equally high affinities for ET-1 and ET-3. No specific receptor for ET-2 was identified. Pancreatic secretagogues that activate phospholipase C (PLC) inhibited binding of 125I-labeled ET-1 (125I-ET-1) or 125I-ET-3, whereas agents that act through adenosine 3',5'-cyclic monophosphate (cAMP) did not. A23187 had no effect on 125I-ET-1 or 125I-ET-3 binding, whereas the phorbol ester 12-O-tetradecanoylphorbol 13-acetate reduced binding. The effect of cholecystokinin octapeptide (CCK-8) was mediated through its own receptor. Stripping of surface bound ligand studies demonstrated that both 125I-labeled ET-1 and 125I-labeled ET-3 were rapidly internalized. CCK-8 decreased the internalization but did not change the amount of surface bound ligand. Endothelins neither stimulate nor alter changes in enzyme secretion, intracellular calcium, cAMP, or [3H]inositol trisphosphate (IP3). This study demonstrates the presence of ETA and ETB receptors on rat pancreatic acini; occupation of both receptors resulted in rapid internalization, which is regulated by PLC-activating secretagogues. Occupation of either ET receptor did not alter intracellular calcium, cAMP, IP3, or stimulate amylase release.

Celecoxib, but not indomethacin, ameliorates the hypertensive and perivascular fibrotic actions of cyclosporine in rats: Role of endothelin signaling

International Nuclear Information System (INIS)

El-Mas, Mahmoud M.; Helmy, Maged W.; Ali, Rabab M.; El-Gowelli, Hanan M.

2015-01-01

The immunosuppressant drug cyclosporine (CSA) is used with nonsteroidal antiinflammatory drugs (NSAIDs) in arthritic conditions. In this study, we investigated whether NSAIDs modify the deleterious hypertensive action of CSA and the role of endothelin (ET) receptors in this interaction. Pharmacologic, protein expression, and histopathologic studies were performed in rats to investigate the roles of endothelin receptors (ET A /ET B ) in the hemodynamic interaction between CSA and two NSAIDs, indomethacin and celecoxib. Tail-cuff plethysmography measurements showed that CSA (20 mg kg −1 day −1 , 10 days) increased systolic blood pressure (SBP) and heart rate (HR). CSA hypertension was associated with renal perivascular fibrosis and divergent changes in immunohistochemical signals of renal arteriolar ET A (increases) and ET B (decreases) receptors. While these effects of CSA were preserved in rats treated concomitantly with indomethacin (5 mg kg −1 day −1 ), celecoxib (10 mg kg −1 day −1 ) abolished the pressor, tachycardic, and fibrotic effects of CSA and normalized the altered renal ET A /ET B receptor expressions. Selective blockade of ET A receptors by atrasentan (5 mg kg −1 day −1 ) abolished the pressor response elicited by CSA or CSA plus indomethacin. Alternatively, BQ788 (ET B receptor blocker, 0.1 mg kg −1 day −1 ) caused celecoxib-sensitive elevations in SBP and potentiated the pressor response evoked by CSA. Together, the improved renovascular fibrotic and endothelin receptor profile (ET A downregulation and ET B upregulation) mediate, at least partly, the protective effect of celecoxib against the hypertensive effect of CSA. Clinically, the use of celecoxib along with CSA in the management of arthritic conditions might provide hypertension-free regimen. - Highlights: • Chronic CSA causes hypertension and renal perivascular fibrosis in rats. • CSA increased and decreased renal ET A and ET B receptor expression, respectively. • CSA

Imaging characteristics of focal splenic and hepatic lesions in type 1 Gaucher disease.

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Regenboog, Martine; Bohte, Anneloes E; Somers, Inne; van Delden, Otto M; Maas, Mario; Hollak, Carla E M

2016-09-01

In Gaucher disease (GD) imaging of liver and spleen is part of routine follow-up of GD patients. Focal lesions in both liver and spleen are frequently reported at radiological examinations. These lesions often represent benign accumulations of Gaucher cells, so-called "gaucheroma", but malignancies, especially hepatocellular carcinoma, are more frequently found in GD as well. We report the imaging characteristics of all focal lesions in liver and spleen in the Dutch GD cohort. Of the 95 GD1 patients, 40% had focal splenic and/or hepatic lesions, associated with more severe GD. Lesions identified as gaucheroma have variable imaging characteristics: hyper- to hypointense on MRI, hyper- or hypoechoic on US and hypodense on computed tomography (CT). Hepatic lesions were classified as simple cysts or haemangioma based upon imaging characteristics. Focal nodular hyperplasia (FNH), gaucheroma and hepatocellular carcinoma (HCC) could not be distinguished by conventional US, CT or MRI. Growth of these lesions and/or characteristics of HCC on dynamic CT or MRI and pathology was used to identify or rule out HCC. We propose a decision-making algorithm including the use of growth and dynamic CT- or MRI-scanning to characterize lesions. Copyright © 2016 Elsevier Inc. All rights reserved.

Nuclear factor κB inhibitor BAY 11-7082 suppresses oxidative stress induced by endothelin-1 (ET-1) in rat kidney.

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Kowalczyk, Agata; Kołodziejczyk, Michał; Gorąca, Anna

2015-12-31

The aim of the study was to evaluate the effect of BAY 11-7082, an NF-κB inhibitor, on basal and ET-1-induced production of reactive oxygen species (ROS), TNF-α and p65 protein in rat kidney. The experimental animals were divided into five groups (n=7) receiving: 1) saline (control); 2 and 3) ET-1 in a dose of 3 μg/kg body weight (b.w.) or 12.5 μg/kg b.w.; 4) BAY 11-7082 (10 mg/kg b.w.); 5) BAY 11-7082 (10 mg/kg b.w.) and ET-1 (12.5 μg/kg b.w.), respectively. In kidney homogenates the concentration of thiobarbituric acid reactive substances (TBARS), H2O2, TNF-α, p65 protein and GSH/GSSG ratio were determined. ET-1 resulted in a dose-dependent increase in TBARS and hydrogen peroxide (H2O2) levels, and a decrease in GSH/GSSG ratio when compared to the controls. BAY 11-7082 administered 1 h before ET-1 administration at a dose of 12.5 μg/kg resulted in a decrease (PET-1 groups. The level of TNF-α was increased (PET-1, while BAY 11-7082 reduced the TNF-α level (PET-1 induced oxidative stress in kidney tissue. These actions of BAY 11-7082 may result from reduced activity of NF-κB signaling pathways. Inhibition of the NF-κB pathway may be a promising strategy for preventing the progression of kidney damage.

Effect of the dual endothelin receptor antagonist bosentan on untreatable skin ulcers in a patient with diabetes: a case report

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Brito Suárez Manuel

2011-04-01

Full Text Available Abstract Introduction Refractory skin ulcers are a major burden in patients with diabetes. Their pathogenesis is multifactorial, and data increasingly implicate endothelin as a mediator of diabetic macro- and microvasculopathy. Here we describe the first reported case of an endothelin receptor antagonist being used to successfully treat refractory skin ulcers in a patient with diabetes. Case presentation An 85-year-old Caucasian man with a 30-year history of type 2 diabetes developed multiple skin ulcerations, including a right heel ulcer. Despite appropriate treatment, the ulcer showed little improvement and the risk of amputation was high. The patient was treated with the dual endothelin receptor antagonist bosentan. After three weeks of treatment, major improvements were observed, and after 21 weeks, all ulcers had healed. No abnormalities were observed during monitoring of blood pressure, erythrocyte sedimentation rate or serum aminotransferase levels. Conclusion In patients with refractory ulceration associated with diabetes, bosentan may be of real benefit, especially in terms of amputation prevention. This case supports the proposed role for endothelin in the pathogenesis of skin ulceration in diabetes and is suggestive of a potential benefit of bosentan in this patient type. This case report is of interest to diabetologists and dermatologists.

Serial neuroradiological studies in focal cerebritis

International Nuclear Information System (INIS)

Hatta, S.; Mochizuki, H.; Kuru, Y.; Miwa, H.; Kondo, T.; Mori, H.; Mizuno, Y.

1994-01-01

We report serial neuroradiological studies in a patient with focal cerebritis in the head of the left caudate nucleus. On the day after the onset of symptoms, CT showed an ill-defined low density lesion. The lack of contrast enhancement appeared to be the most important finding for differentiating focal cerebritis from an encapsulated brain abscess or a tumour. MRI two days later revealed the centre of the lesion to be of slightly low intensity on T1-weighted inversion recovery (IR) images and very low intensity on T2-weighted spin echo images, which appeared to correspond to the early cerebritis stage of experimentally induced cerebritis and brain abscess. Ten days after the onset of symptoms, CT revealed a thin ring of enhancement in the head of the caudate nucleus, and a similar small ring was seen in the hypothalamus 16 days after the onset, corresponding to the late cerebritis stage. MRI nine days later revealed ill-defined high signal lesions within the involved area on the T1-weighted IR images. To our knowledge, this is the first published MRI documentation of the early cerebritis stage developing into an encapsulated brain abscess. The mechanisms underlying of these radiographic changes are discussed. (orig.)

Second-hit mosaic mutation in mTORC1 repressor DEPDC5 causes focal cortical dysplasia-associated epilepsy.

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Ribierre, Théo; Deleuze, Charlotte; Bacq, Alexandre; Baldassari, Sara; Marsan, Elise; Chipaux, Mathilde; Muraca, Giuseppe; Roussel, Delphine; Navarro, Vincent; Leguern, Eric; Miles, Richard; Baulac, Stéphanie

2018-04-30

DEP domain-containing 5 protein (DEPDC5) is a repressor of the recently recognized amino acid-sensing branch of the mTORC1 pathway. So far, its function in the brain remains largely unknown. Germline loss-of-function mutations in DEPDC5 have emerged as a major cause of familial refractory focal epilepsies, with case reports of sudden unexpected death in epilepsy (SUDEP). Remarkably, a fraction of patients also develop focal cortical dysplasia (FCD), a neurodevelopmental cortical malformation. We therefore hypothesized that a somatic second-hit mutation arising during brain development may support the focal nature of the dysplasia. Here, using postoperative human tissue, we provide the proof of concept that a biallelic 2-hit - brain somatic and germline - mutational mechanism in DEPDC5 causes focal epilepsy with FCD. We discovered a mutation gradient with a higher rate of mosaicism in the seizure-onset zone than in the surrounding epileptogenic zone. Furthermore, we demonstrate the causality of a Depdc5 brain mosaic inactivation using CRISPR-Cas9 editing and in utero electroporation in a mouse model recapitulating focal epilepsy with FCD and SUDEP-like events. We further unveil a key role of Depdc5 in shaping dendrite and spine morphology of excitatory neurons. This study reveals promising therapeutic avenues for treating drug-resistant focal epilepsies with mTORC1-targeting molecules.

Stimuli of Sensory-Motor Nerves Terminate Arterial Contractile Effects of Endothelin-1 by CGRP and Dissociation of ET-1/ETA-Receptor Complexes

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Meens, Merlijn J. P. M. T.; Compeer, Matthijs G.; Hackeng, Tilman M.; van Zandvoort, Marc A.; Janssen, Ben J. A.; De Mey, Jo G. R.

2010-01-01

Background Endothelin-1 (ET-1), a long-acting paracrine mediator, is implicated in cardiovascular diseases but clinical trials with ET-receptor antagonists were not successful in some areas. We tested whether the quasi-irreversible receptor-binding of ET-1 (i) limits reversing effects of the antagonists and (ii) can be selectively dissociated by an endogenous counterbalancing mechanism. Methodology/Principal findings In isolated rat mesenteric resistance arteries, ETA-antagonists, endothelium-derived relaxing factors and synthetic vasodilators transiently reduced contractile effects of ET-1 but did not prevent persistent effects of the peptide. Stimuli of peri-vascular vasodilator sensory-motor nerves such as capsaicin not only reduced but also terminated long-lasting effects of ET-1. This was prevented by CGRP-receptor antagonists and was mimicked by exogenous calcitonin gene-related peptide (CGRP). Using 2-photon laser scanning microscopy in vital intact arteries, capsaicin and CGRP, but not ETA-antagonism, were observed to promote dissociation of pre-existing ET-1/ETA-receptor complexes. Conclusions Irreversible binding and activation of ETA-receptors by ET-1 (i) occur at an antagonist-insensitive site of the receptor and (ii) are selectively terminated by endogenously released CGRP. Hence, natural stimuli of sensory-motor nerves that stimulate release of endogenous CGRP can be considered for therapy of diseases involving ET-1. PMID:20532232

Endothelin-1 and endothelin-2 initiate and maintain contractile responses by different mechanisms in rat mesenteric and cerebral arteries

DEFF Research Database (Denmark)

Compeer, M. G.; Janssen, G. M. J.; De Mey, J. G. R.

2013-01-01

, but relaxed ET-1-induced contractions in MRA. A PLC inhibitor prevented contractile responses to ET-1 and ET-2 in MRA and BA, and relaxed ET-1- and ET-2-induced responses in MRA and ET-1 effects in BA. A Rho-kinase inhibitor did not modify sensitivity, maximum and maintenance of responses to both peptides...... in both arteries but relaxed ET-2, but not ET-1, effects in MRA and ET-1 effects in BA. Conclusions and ImplicationsPLC played a key role in arterial contractile responses to ETs, but ET-1 and ET-2 initiated and maintained vasoconstriction through different mechanisms, and these differed between MRA...

CPU0213, a novel endothelin type A and type B receptor antagonist, protects against myocardial ischemia/reperfusion injury in rats

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Z.Y. Wang

2011-11-01

Full Text Available The efficacy of endothelin receptor antagonists in protecting against myocardial ischemia/reperfusion (I/R injury is controversial, and the mechanisms remain unclear. The aim of this study was to investigate the effects of CPU0123, a novel endothelin type A and type B receptor antagonist, on myocardial I/R injury and to explore the mechanisms involved. Male Sprague-Dawley rats weighing 200-250 g were randomized to three groups (6-7 per group: group 1, Sham; group 2, I/R + vehicle. Rats were subjected to in vivo myocardial I/R injury by ligation of the left anterior descending coronary artery and 0.5% sodium carboxymethyl cellulose (1 mL/kg was injected intraperitoneally immediately prior to coronary occlusion. Group 3, I/R + CPU0213. Rats were subjected to identical surgical procedures and CPU0213 (30 mg/kg was injected intraperitoneally immediately prior to coronary occlusion. Infarct size, cardiac function and biochemical changes were measured. CPU0213 pretreatment reduced infarct size as a percentage of the ischemic area by 44.5% (I/R + vehicle: 61.3 ± 3.2 vs I/R + CPU0213: 34.0 ± 5.5%, P < 0.05 and improved ejection fraction by 17.2% (I/R + vehicle: 58.4 ± 2.8 vs I/R + CPU0213: 68.5 ± 2.2%, P < 0.05 compared to vehicle-treated animals. This protection was associated with inhibition of myocardial inflammation and oxidative stress. Moreover, reduction in Akt (protein kinase B and endothelial nitric oxide synthase (eNOS phosphorylation induced by myocardial I/R injury was limited by CPU0213 (P < 0.05. These data suggest that CPU0123, a non-selective antagonist, has protective effects against myocardial I/R injury in rats, which may be related to the Akt/eNOS pathway.

Increased expression of endothelin ET(B) and angiotensin AT(1) receptors in peripheral resistance arteries of patients with suspected acute coronary syndrome

DEFF Research Database (Denmark)

Dimitrijevic, Ivan; Ekelund, Ulf; Edvinsson, Lars

2009-01-01

of arterial vasoconstrictor endothelin (ET) and angiotensin (AT) receptors. Our aim was to investigate if the arterial expressions of these receptors are changed in patients with suspected but ruled out acute coronary syndrome (ACS). Small subcutaneous arteries (diameter of 100 microm) were surgically removed...... in the regulation of coronary tone and in the development of atherosclerosis, and may be related to increased cardiovascular risk....

Electric field strength and focality in electroconvulsive therapy and magnetic seizure therapy: a finite element simulation study

Science.gov (United States)

Deng, Zhi-De; Lisanby, Sarah H.; Peterchev, Angel V.

2011-02-01

We present the first computational study comparing the electric field induced by various electroconvulsive therapy (ECT) and magnetic seizure therapy (MST) paradigms. Four ECT electrode configurations (bilateral, bifrontal, right unilateral, and focal electrically administered seizure therapy) and three MST coil configurations (circular, cap, and double cone) were modeled. The model incorporated a modality-specific neural activation threshold. ECT (0.3 ms pulse width) and MST induced the maximum electric field of 2.1-2.5 V cm-1 and 1.1-2.2 V cm-1 in the brain, corresponding to 6.2-7.2 times and 1.2-2.3 times the neural activation threshold, respectively. The MST electric field is more confined to the superficial cortex compared to ECT. The brain volume stimulated was much larger with ECT (up to 100%) than with MST (up to 8.2%). MST with the double-cone coil was the most focal, and bilateral ECT was the least focal. Our results suggest a possible biophysical explanation of the reduced side effects of MST compared to ECT. Our results also indicate that the conventional ECT pulse amplitude (800-900 mA) is much higher than necessary for seizure induction. Reducing the ECT pulse amplitude should be explored as a potential means of diminishing side effects.

Exercise capacity is associated with endothelin-1 release during emotional excitement in coronary artery disease patients.

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Tulppo, Mikko P; Piira, Olli-Pekka; Hautala, Arto J; Kiviniemi, Antti M; Miettinen, Johanna A; Huikuri, Heikki V

2014-08-01

Endothelin-1 (ET-1), a potent vasoconstrictor, IL-6, and catecholamines are increased and heart rate variability [SD of normal to normal R-R intervals (SDNN)] decreased during emotional excitement, but individual responses vary. We tested the hypothesis that exercise capacity is associated with physiological responses caused by real-life emotional excitement. We measured the plasma levels of ET-1, IL-6, catecholamines, heart rate, and SDNN in enthusiastic male ice hockey spectators (n = 51; age, 59 ± 9 years) with stable coronary artery disease (CAD) at baseline and during the Finnish National Ice Hockey League's final play-off matches. Maximal exercise capacity (METs) by bicycle exercise test and left ventricular ejection fraction (LVEF) were measured on a separate day. ET-1 response from baseline to emotional excitement correlated with maximal METs (r = -0.30; P = 0.040). In a linear stepwise regression analysis age, body mass index (BMI), METs, LVEF, basal ET-1, and subjective experience of excitement were entered the model as independent variables to explain ET-1 response. This model explained 27% of ET-1 response (P = 0.003). Maximal METs were most strongly correlated with ET-1 response (β = -0.45; partial correlation r = -0.43; P = 0.002), followed by BMI (β = -0.31; partial correlation r = -0.31; P = 0.033) and LVEF (β = -0.30; partial correlation r = -0.33; P = 0.023). Exercise capacity may protect against further cardiovascular events in CAD patients, because it is associated with reduced ET-1 release during emotional excitement. Copyright © 2014 the American Physiological Society.

Focal myositis

International Nuclear Information System (INIS)

Kransdorf, M.J.; Temple, H.T.; Sweet, D.E.

1998-01-01

Focal myositis is a pseudotumor of soft tissue that typically occurs in the deep soft tissue of the extremities, and is a relatively rare lesion. There is a wide clinical spectrum, with approximately one-third of patients with focal myositis subsequently developing polymyositis, and clinical symptoms of generalized weakness, fever, myalgia, and weight loss, with elevation of creatine phosphokinase. We report the case of a patient with focal myositis who subsequently developed myositis ossificans-like features. (orig.)

Experimental Study of the Effects of EIPA, Losartan, and BQ-123 on Electrophysiological Changes Induced by Myocardial Stretch.

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Chorro, Francisco J; Canto, Irene Del; Brines, Laia; Such-Miquel, Luis; Calvo, Conrado; Soler, Carlos; Zarzoso, Manuel; Trapero, Isabel; Tormos, Álvaro; Such, Luis

2015-12-01

Mechanical response to myocardial stretch has been explained by various mechanisms, which include Na(+)/H(+) exchanger activation by autocrine-paracrine system activity. Drug-induced changes were analyzed to investigate the role of these mechanisms in the electrophysiological responses to acute myocardial stretch. Multiple epicardial electrodes and mapping techniques were used to analyze changes in ventricular fibrillation induced by acute myocardial stretch in isolated perfused rabbit hearts. Four series were studied: control (n = 9); during perfusion with the angiotensin receptor blocker losartan (1 μM, n = 8); during perfusion with the endothelin A receptor blocker BQ-123 (0.1 μM, n = 9), and during perfusion with the Na(+)/H(+) exchanger inhibitor EIPA (5-[N-ethyl-N-isopropyl]-amiloride) (1 μM, n = 9). EIPA attenuated the increase in the dominant frequency of stretch-induced fibrillation (control=40.4%; losartan=36% [not significant]; BQ-123=46% [not significant]; and EIPA=22% [PII receptor antagonist losartan and the endothelin A receptor blocker BQ-123 did not modify these effects. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

HIGH PERFORMANCE PIAA CORONAGRAPHY WITH COMPLEX AMPLITUDE FOCAL PLANE MASKS

International Nuclear Information System (INIS)

Guyon, Olivier; Martinache, Frantz; Belikov, Ruslan; Soummer, Remi

2010-01-01

We describe a coronagraph approach where the performance of a Phase-Induced Amplitude Apodization (PIAA) coronagraph is improved by using a partially transmissive phase-shifting focal plane mask and a Lyot stop. This approach combines the low inner working angle offered by phase mask coronagraphy, the full throughput and uncompromized angular resolution of the PIAA approach, and the design flexibility of Apodized Pupil Lyot Coronagraph. A PIAA complex mask coronagraph (PIAACMC) is fully described by the focal plane mask size, or, equivalently, its complex transmission which ranges from 0 (opaque) to -1 (phase shifting). For all values of the transmission, the PIAACMC theoretically offers full on-axis extinction and 100% throughput at large angular separations. With a pure phase focal plane mask (complex transmission = -1), the PIAACMC offers 50% throughput at 0.64 λ/D while providing total extinction of an on-axis point source. This performance is very close to the 'fundamental performance limit' of coronagraphy derived from first principles. For very high contrast level, imaging performance with PIAACMC is in practice limited by the angular size of the on-axis target (usually a star). We show that this fundamental limitation must be taken into account when choosing the optimal value of the focal plane mask size in the PIAACMC design. We show that the PIAACMC enables visible imaging of Jupiter-like planets at ∼1.2 λ/D from the host star, and can therefore offer almost three times more targets than a PIAA coronagraph optimized for this type of observation. We find that for visible imaging of Earth-like planets, the PIAACMC gain over a PIAA is probably much smaller, as coronagraphic performance is then strongly constrained by stellar angular size. For observations at 'low' contrast (below ∼ 10 8 ), the PIAACMC offers significant performance enhancement over PIAA. This is especially relevant for ground-based high contrast imaging systems in the near-IR, where

Production of high energy, uniform focal profiles with the Nike laser

Science.gov (United States)

Lehecka, T.; Lehmberg, R. H.; Deniz, A. V.; Gerber, K. A.; Obenschain, S. P.; Pawley, C. J.; Pronko, M. S.; Sullivan, C. A.

1995-02-01

Nike, a KrF laser facility at the Naval Research Laboratory, is designed to produce high intensity, ultra-uniform focal profiles for experiments relating to direct drive inertial confinement fusion. We present measurements of focal profiles through the next-to-last amplifier, a 20 × 20 cm 2 aperture electron beam pumped amplifier capable of producing more than 120 J of output in a 120 ns pulse. Using echelon free induced spatial incoherence beam smoothing this system has produced focal profiles with less than 2% tilt and curvature and less than 2% rms variation from a flat top distribution.

Focal myositis

Energy Technology Data Exchange (ETDEWEB)

Kransdorf, M.J. [Saint Mary`s Hospital, Richmond, VA (United States). Dept. of Radiol.]|[Department of Radiologic Pathology, Armed Forces Institute of Pathology, Washington, DC (United States); Temple, H.T. [Department of Orthopedic Surgery, University of Virginia Health Sciences Center, Charlottesville, Virginia (United States)]|[Department of Orthopedic Pathology, Armed Forces Institute of Pathology, Washington, DC (United States); Sweet, D.E. [Department of Orthopedic Pathology, Armed Forces Institute of Pathology, Washington, DC (United States)

1998-05-01

Focal myositis is a pseudotumor of soft tissue that typically occurs in the deep soft tissue of the extremities, and is a relatively rare lesion. There is a wide clinical spectrum, with approximately one-third of patients with focal myositis subsequently developing polymyositis, and clinical symptoms of generalized weakness, fever, myalgia, and weight loss, with elevation of creatine phosphokinase. We report the case of a patient with focal myositis who subsequently developed myositis ossificans-like features. (orig.) With 3 figs., 25 refs.

Novel nonsense mutation of the endothelin-B receptor gene in a family with Waardenburg-Hirschsprung disease.

Science.gov (United States)

Syrris, P; Carter, N D; Patton, M A

1999-11-05

Waardenburg syndrome (WS) comprises sensorineural hearing loss, hypopigmentation of skin and hair, and pigmentary disturbances of the irides. Four types of WS have been classified to date; in WS type IV (WS4), patients additionally have colonic aganglionosis (Hirschsprung disease, HSCR). Mutations in the endothelin-3 (EDN3), endothelin-B receptor (EDNRB), and Sox10 genes have been identified as causative for WS type IV. We screened a family with a combined WS-HSCR phenotype for mutations in the EDNRB locus using standard DNA mutation analysis and sequencing techniques. We have identified a novel nonsense mutation at codon 253 (CGA-->TGA, Arg-->STOP). This mutation leads to a premature end of the translation of EDNRB at exon 3, and it is predicted to produce a truncated and nonfunctional endothelin-B receptor. All affected relatives were heterozygous for the Arg(253)-->STOP mutation, whereas it was not observed in over 50 unrelated individuals used as controls. These data confirm the role of EDNRB in the cause of the Waardenburg-Hirschsprung syndrome and demonstrate that in WS-HSCR there is a lack of correlation between phenotype and genotype and a variable expression of disease even within the same family. Copyright 1999 Wiley-Liss, Inc.

Enhanced expression of Gqα and PLC-β1 proteins contributes to vascular smooth muscle cell hypertrophy in SHR: role of endogenous angiotensin II and endothelin-1.

Science.gov (United States)

Atef, Mohammed Emehdi; Anand-Srivastava, Madhu B

2014-07-01

Vascular Gqα signaling has been shown to contribute to cardiac hypertrophy. In addition, angiotensin II (ANG II) was shown to induce vascular smooth muscle cell (VSMC) hypertrophy through Gqα signaling; however, the studies on the role of Gqα and PLC-β1 proteins in VSMC hypertrophy in animal model are lacking. The present study was therefore undertaken to examine the role of Gqα/PLC-β1 proteins and the signaling pathways in VSMC hypertrophy using spontaneously hypertensive rats (SHR). VSMC from 16-wk-old SHR and not from 12-wk-old SHR exhibited enhanced levels of Gqα/PLC-β1 proteins compared with age-matched Wistar-Kyoto (WKY) rats as determined by Western blotting. However, protein synthesis as determined by [(3)H]leucine incorporation was significantly enhanced in VSMC from both 12- and 16-wk-old SHR compared with VSMC from age-matched WKY rats. Furthermore, the knockdown of Gqα/PLC-β1 in VSMC from 16-wk-old SHR by antisense and small interfering RNA resulted in attenuation of protein synthesis. In addition, the enhanced expression of Gqα/PLC-β1 proteins, enhanced phosphorylation of ERK1/2, and enhanced protein synthesis in VSMC from SHR were attenuated by the ANG II AT1 and endothelin-1 (ET-1) ETA receptor antagonists losartan and BQ123, respectively, but not by the ETB receptor antagonist BQ788. In addition, PD98059 decreased the enhanced expression of Gqα/PLC-β1 and protein synthesis in VSMC from SHR. These results suggest that the enhanced levels of endogenous ANG II and ET-1 through the activation of AT1 and ETA receptors, respectively, and MAP kinase signaling, enhanced the expression of Gqα/PLC-β1 proteins in VSMC from 16-wk-old SHR and result in VSMC hypertrophy. Copyright © 2014 the American Physiological Society.

Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

International Nuclear Information System (INIS)

Crowe, David L; Ohannessian, Arthur

2004-01-01

Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK). Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK). Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC) lines. Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway

Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

Directory of Open Access Journals (Sweden)

Ohannessian Arthur

2004-05-01

Full Text Available Abstract Background Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK. Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK. Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC lines. Methods Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. Results In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. Conclusions We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway.

Classification of Focal and Non Focal Epileptic Seizures Using Multi-Features and SVM Classifier.

Science.gov (United States)

Sriraam, N; Raghu, S

2017-09-02

Identifying epileptogenic zones prior to surgery is an essential and crucial step in treating patients having pharmacoresistant focal epilepsy. Electroencephalogram (EEG) is a significant measurement benchmark to assess patients suffering from epilepsy. This paper investigates the application of multi-features derived from different domains to recognize the focal and non focal epileptic seizures obtained from pharmacoresistant focal epilepsy patients from Bern Barcelona database. From the dataset, five different classification tasks were formed. Total 26 features were extracted from focal and non focal EEG. Significant features were selected using Wilcoxon rank sum test by setting p-value (p z > 1.96) at 95% significance interval. Hypothesis was made that the effect of removing outliers improves the classification accuracy. Turkey's range test was adopted for pruning outliers from feature set. Finally, 21 features were classified using optimized support vector machine (SVM) classifier with 10-fold cross validation. Bayesian optimization technique was adopted to minimize the cross-validation loss. From the simulation results, it was inferred that the highest sensitivity, specificity, and classification accuracy of 94.56%, 89.74%, and 92.15% achieved respectively and found to be better than the state-of-the-art approaches. Further, it was observed that the classification accuracy improved from 80.2% with outliers to 92.15% without outliers. The classifier performance metrics ensures the suitability of the proposed multi-features with optimized SVM classifier. It can be concluded that the proposed approach can be applied for recognition of focal EEG signals to localize epileptogenic zones.

Focal Stroke in the Developing Rat Motor Cortex Induces Age- and Experience-Dependent Maladaptive Plasticity of Corticospinal System.

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Gennaro, Mariangela; Mattiello, Alessandro; Mazziotti, Raffaele; Antonelli, Camilla; Gherardini, Lisa; Guzzetta, Andrea; Berardi, Nicoletta; Cioni, Giovanni; Pizzorusso, Tommaso

2017-01-01

Motor system development is characterized by an activity-dependent competition between ipsilateral and contralateral corticospinal tracts (CST). Clinical evidence suggests that age is crucial for developmental stroke outcome, with early lesions inducing a "maladaptive" strengthening of ipsilateral projections from the healthy hemisphere and worse motor impairment. Here, we investigated in developing rats the relation between lesion timing, motor outcome and CST remodeling pattern. We induced a focal ischemia into forelimb motor cortex (fM1) at two distinct pre-weaning ages: P14 and P21. We compared long-term motor outcome with changes in axonal sprouting of contralesional CST at red nucleus and spinal cord level using anterograde tracing. We found that P14 stroke caused a more severe long-term motor impairment than at P21, and induced a strong and aberrant contralesional CST sprouting onto denervated spinal cord and red nucleus. The mistargeted sprouting of CST, and the worse motor outcome of the P14 stroke rats were reversed by an early skilled motor training, underscoring the potential of early activity-dependent plasticity in modulating lesion outcome. Thus, changes in the mechanisms controlling CST plasticity occurring during the third postnatal week are associated with age-dependent regulation of the motor outcome after stroke.

Prenatal sonographic diagnosis of focal musculoskeletal anomalies

International Nuclear Information System (INIS)

Ryu, Jung-Kyu; Cho, Jeong-Yeon; Choi, Jong-Sun

2003-01-01

Focal musculoskeletal anomalies vary, and can manifest as part of a syndrome or be accompanied by numerous other conditions such as genetic disorders, karyotype abnormalities, central nervous system anomalies and other skeletal anomalies, lsolated focal musculoskeletal anomaly does, however, also occur; its early prenatal diagnosis is important in deciding prenatal care, and also helps in counseling parents about the postnatal effects of numerous possible associated anomalies. We have encountered 50 cases involving focal musculoskeletal anomalies, including total limb dysplasia [radial ray abnormality (n=3), mesomelic dysplasia (n=1)]; anomalies of the hand [polydactyly (n=8), syndactyly (n=3), ectrodactyly (n=1), clinodactyly (n=6), clenched hand (n=5)]; anomalies of the foot [clubfoot (n=10), rockerbottom foot (n=5), sandal gap deformity (n=1), curly toe (n=2)]; amniotic band syndrome (n=3); and anomalies of the focal spine [block vertebra (n=1), hemivertebra (n=1)]. Among these 50 cases, five [polydactyly (n=1), syndactyly (n=2) and curly toe (n=2) were confirmed by postnatal physical evaluation, two (focal spine anomalies) were diagnosed after postnatal radiologic examination, and the remaining 43 were proven at autopsy. For each condition, we describe the prenatal sonographic findings, and include a brief review

Prenatal sonographic diagnosis of focal musculoskeletal anomalies

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jung-Kyu; Cho, Jeong-Yeon; Choi, Jong-Sun [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2003-12-15

Focal musculoskeletal anomalies vary, and can manifest as part of a syndrome or be accompanied by numerous other conditions such as genetic disorders, karyotype abnormalities, central nervous system anomalies and other skeletal anomalies, lsolated focal musculoskeletal anomaly does, however, also occur; its early prenatal diagnosis is important in deciding prenatal care, and also helps in counseling parents about the postnatal effects of numerous possible associated anomalies. We have encountered 50 cases involving focal musculoskeletal anomalies, including total limb dysplasia [radial ray abnormality (n=3), mesomelic dysplasia (n=1)]; anomalies of the hand [polydactyly (n=8), syndactyly (n=3), ectrodactyly (n=1), clinodactyly (n=6), clenched hand (n=5)]; anomalies of the foot [clubfoot (n=10), rockerbottom foot (n=5), sandal gap deformity (n=1), curly toe (n=2)]; amniotic band syndrome (n=3); and anomalies of the focal spine [block vertebra (n=1), hemivertebra (n=1)]. Among these 50 cases, five [polydactyly (n=1), syndactyly (n=2) and curly toe (n=2) were confirmed by postnatal physical evaluation, two (focal spine anomalies) were diagnosed after postnatal radiologic examination, and the remaining 43 were proven at autopsy. For each condition, we describe the prenatal sonographic findings, and include a brief review.

Clinical value of plasma endothelin levels in children with cardiovascular diseases

International Nuclear Information System (INIS)

Chen Nianfa; Duan Yongqiang

2009-01-01

To explore the clinical value of plasma endothelin (ET-1) levels in children with cardiovascular diseases, 77 children with heart failure, obesity, hyperlipemia, fatty liver and hypertension were divided into 5 experimental groups and 21 health children with same age and gender as control group. The plasma levels of ET-1 in these children were tested by RIA. The results showed that plasma levels of ET-1 in 5 experimental groups were 112.8 ± 34.1ng/L, 57.8 ± 19.1ng/L,64.5 ± 25.3ng/L, 74.9 ± 28.4ng/L and 60.7 ± 21.6ng/L, respectively. The ET-1 levels in 5 groups were significantly higher than that in control group (P<0.01). The results indicate the higher plasma ET-1 levels in children are related with cardiovascular diseases, and it is useful in the diagnosis of children cardiovascular diseases. (authors)

Inhibitory effect of rhynchophylline on contraction of cerebral arterioles to endothelin 1: role of rho kinase.

Science.gov (United States)

Hao, Hui-Feng; Liu, Li-Mei; Liu, Yu-Ying; Liu, Juan; Yan, Li; Pan, Chun-Shui; Wang, Ming-Xia; Wang, Chuan-She; Fan, Jing-Yu; Gao, Yuan-Sheng; Han, Jing-Yan

2014-08-08

Rhynchophylline (Rhy) is a major ingredient of Uncaria rhynchophylla (UR) used to reduce blood pressure and ameliorate brain ailments. This study was to examine the role of Rho kinase (ROCK) in the inhibition of Rhy on contraction of cerebral arterioles caused by endothelin 1 (ET-1). Cerebral arterioles of male Wistar rats were constricted with ET-1 for 10 min followed by perfusion of Rhy for 20 min. Changes in the diameters of the arterioles were recorded. The effects of Rhy on contraction of middle cerebral arteries (MCAs) were determined by a Multi-Myograph. Western blotting and immunofluorescent staining were used to examine the effects of Rhy on RhoA translocation and myosin phosphatase target subunit 1 (MYPT1) phosphorylation. In vivo, Rhy (30-300 µM) relaxed cerebral arterioles constricted with ET-1 dose-dependently. In vitro, Rhy at lower concentrations (1-100 µM) caused relaxation of rat MCAs constricted with KCl and Bay-K8644 (an agonist of L-type voltage-dependent calcium channels (L-VDCCs)). Rhy at higher concentrations (>100 µM) caused relaxation of rat MCAs constricted with ET-1, which was inhibited by Y27632, a ROCK׳s inhibitor. Western blotting of rat aortas showed that Rhy inhibited RhoA translocation and MYPT1 phosphorylation. Immunofluorescent staining of MCAs confirmed that phosphorylation of MYPT1 caused by ET-1 was inhibited by Rhy. These results demonstrate that Rhy is a potent inhibitor of contraction of cerebral arteries caused by ET-1 in vivo and in vitro. The effect of Rhy was in part mediated by inhibiting RhoA-ROCK signaling. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Correlation of endothelin-1 concentration and angiotensin-converting enzyme activity with the staging of liver fibrosis.

Science.gov (United States)

Kardum, Dusko; Fabijanić, Damir; Lukić, Anita; Romić, Zeljko; Petrovecki, Mladen; Bogdanović, Zoran; Jurić, Klara; Urek-Crncević, Marija; Banić, Marko

2012-06-01

Increased serum angiotensin-converting enzyme (SACE) activity and serum concentration of endothelin-1 (ET-1) were found in liver cirrhosis. We investigated a correlation between the different stages of liver fibrosis and SACE activity and serum ET-1 concentration. Seventy patients with pathohistologically established chronic liver disease were divided in three groups according to Ishak criteria for liver fibrosis: minimal fibrosis (Ishak score 0-1, n =20), medium fibrosis (Ishak score 2-5, n=20) and cirrhosis (Ishak score 6, n=30). SACE activity and ET-1 concentration were determined using commercial ELISA kits. SACE activity and ET-1 concentrations were proportional to the severity of disease, the highest being in patients with liver cirrhosis. Maximal increase in SACE activity was found between minimal and medium fibrosis while maximal increase in ET-1 concentration was revealed between medium fibrosis and cirrhosis. The analysis of the Receiver Operating Characteristic (ROC) curve for SACE activity suggested a cut-off value to separate minimal from medium fibrosis at 59.00 U/L (sensitivity 100%, specificity 64.7%). The cut-off value for serum ET-1 concentration to separate medium fibrosis from cirrhosis was 12.4 pg/mL (sensitivity 96.8%, specificity 94.4%). A positive correlation between SACE activity and ET-1 concentration was registered (Spearman's ñ = 0.438, p = 0.004). Both SACE activity and ET-1 concentration were increased in all stages of liver fibrosis. Cut-off points for SACE activity and ET-1 concentration could be a biochemical marker for the progression of fibrosis. Positive correlation between SACE activity and ET-1 concentration might indicate their interaction in the development of liver cirrhosis.

Statin-induced focal myositis of the upper extremity. A report of two cases

International Nuclear Information System (INIS)

Wagner, M.; Muehldorfer-Fodor, M.; Prommersberger, K.J.; Schmitt, R.

2011-01-01

Statins are widely used to lower increased cholesterol levels with the aim to prevent major cardiovascular events. However, they bare the risk of myotoxic side effects. We report on two patients with focal weakness and pain in the upper extremities. In both patients, abnormal MRI signal heights in the muscle groups involved were indicative of the final diagnosis of focal myositis during statin therapy.

Statin-induced focal myositis of the upper extremity. A report of two cases

Energy Technology Data Exchange (ETDEWEB)

Wagner, M., E-mail: wagner.radiologie@herzchirurgie.de [Department of Radiology, Herz- und Gefaessklinik GmbH, Salzburger Leite 1, D-97616 Bad Neustadt an der Saale (Germany); Muehldorfer-Fodor, M.; Prommersberger, K.J. [Department of Handsurgery, Herz- und Gefaessklinik GmbH, Bad Neustadt an der Saale (Germany); Schmitt, R. [Department of Radiology, Herz- und Gefaessklinik GmbH, Salzburger Leite 1, D-97616 Bad Neustadt an der Saale (Germany)

2011-02-15

Statins are widely used to lower increased cholesterol levels with the aim to prevent major cardiovascular events. However, they bare the risk of myotoxic side effects. We report on two patients with focal weakness and pain in the upper extremities. In both patients, abnormal MRI signal heights in the muscle groups involved were indicative of the final diagnosis of focal myositis during statin therapy.

Endothelin-A receptor blockade slows the progression of renal injury in experimental renovascular disease.

Science.gov (United States)

Kelsen, Silvia; Hall, John E; Chade, Alejandro R

2011-07-01

Endothelin (ET)-1, a potent renal vasoconstrictor with mitogenic properties, is upregulated by ischemia and has been shown to induce renal injury via the ET-A receptor. The potential role of ET-A blockade in chronic renovascular disease (RVD) has not, to our knowledge, been previously reported. We hypothesized that chronic ET-A receptor blockade would preserve renal hemodynamics and slow the progression of injury of the stenotic kidney in experimental RVD. Renal artery stenosis, a major cause of chronic RVD, was induced in 14 pigs and observed for 6 wk. In half of the pigs, chronic ET-A blockade was initiated (RVD+ET-A, 0.75 mg·kg(-1)·day(-1)) at the onset of RVD. Single-kidney renal blood flow, glomerular filtration rate, and perfusion were quantified in vivo after 6 wk using multidetector computer tomography. Renal microvascular density was quantified ex vivo using three-dimensional microcomputer tomography, and growth factors, inflammation, apoptosis, and fibrosis were determined in renal tissue. The degree of stenosis and increase in blood pressure were similar in RVD and RVD+ET-A pigs. Renal hemodynamics, function, and microvascular density were decreased in the stenotic kidney but preserved by ET-A blockade, accompanied by increased renal expression of vascular endothelial growth factor, hepatocyte growth factor, and downstream mediators such as phosphorilated-Akt, angiopoietins, and endothelial nitric oxide synthase. ET-A blockade also reduced renal apoptosis, inflammation, and glomerulosclerosis. This study shows that ET-A blockade slows the progression of renal injury in experimental RVD and preserves renal hemodynamics, function, and microvascular density in the stenotic kidney. These results support a role for ET-1/ET-A as a potential therapeutic target in chronic RVD.

Stimuli of sensory-motor nerves terminate arterial contractile effects of endothelin-1 by CGRP and dissociation of ET-1/ET(A-receptor complexes.

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Merlijn J P M T Meens

Full Text Available BACKGROUND: Endothelin-1 (ET-1, a long-acting paracrine mediator, is implicated in cardiovascular diseases but clinical trials with ET-receptor antagonists were not successful in some areas. We tested whether the quasi-irreversible receptor-binding of ET-1 (i limits reversing effects of the antagonists and (ii can be selectively dissociated by an endogenous counterbalancing mechanism. METHODOLOGY/PRINCIPAL FINDINGS: In isolated rat mesenteric resistance arteries, ET(A-antagonists, endothelium-derived relaxing factors and synthetic vasodilators transiently reduced contractile effects of ET-1 but did not prevent persistent effects of the peptide. Stimuli of peri-vascular vasodilator sensory-motor nerves such as capsaicin not only reduced but also terminated long-lasting effects of ET-1. This was prevented by CGRP-receptor antagonists and was mimicked by exogenous calcitonin gene-related peptide (CGRP. Using 2-photon laser scanning microscopy in vital intact arteries, capsaicin and CGRP, but not ET(A-antagonism, were observed to promote dissociation of pre-existing ET-1/ET(A-receptor complexes. CONCLUSIONS: Irreversible binding and activation of ET(A-receptors by ET-1 (i occur at an antagonist-insensitive site of the receptor and (ii are selectively terminated by endogenously released CGRP. Hence, natural stimuli of sensory-motor nerves that stimulate release of endogenous CGRP can be considered for therapy of diseases involving ET-1.

Enhanced expressions of microvascular smooth muscle receptors after focal cerebral ischemia occur via the MAPK MEK/ERK pathway

DEFF Research Database (Denmark)

Maddahi, A.; Edvinsson, L.

2008-01-01

), the enhanced vascular receptor expression, and attenuated the cerebral infarct and improved neurology score. CONCLUSION: Our results show that MCAO results in upregulation of cerebrovascular ETB, AT1 and 5-HT1B receptors. Blockade of this event with a MEK1 inhibitor as late as 6 h after the insult reduced...... the role of the MEK/ERK pathway in receptor expression following ischemic brain injury using the specific MEK1 inhibitor U0126. METHODS AND RESULT: Rats were subjected to a 2-h middle cerebral artery occlusion (MCAO) followed by reperfusion for 48-h and the ischemic area was calculated. The expression...... of phosphorylated ERK1/2 and Elk-1, and of endothelin ETA and ETB, angiotensin AT1, and 5-hydroxytryptamine 5-HT1B receptors were analyzed with immunohistochemistry using confocal microscopy in cerebral arteries, microvessels and in brain tissue. The expression of endothelin ETB receptor was analyzed...

A homozygous mutation in the endothelin-3 gene associated with a combined Waardenburg type 2 and Hirschsprung phenotype (Shah-Waardenburg syndrome).

Science.gov (United States)

Hofstra, R M; Osinga, J; Tan-Sindhunata, G; Wu, Y; Kamsteeg, E J; Stulp, R P; van Ravenswaaij-Arts, C; Majoor-Krakauer, D; Angrist, M; Chakravarti, A; Meijers, C; Buys, C H

1996-04-01

Hirschsprung disease (HSCR) or colonic aganglionosis is a congenital disorder characterized by an absence of intramural ganglia along variable lengths of the colon resulting in intestinal obstruction. The incidence of HSCR is 1 in 5,000 live births. Mutations in the RET gene, which codes for a receptor tyrosine kinase, and in EDNRB which codes for the endothelin-B receptor, have been shown to be associated with HSCR in humans. The lethal-spotted mouse which has pigment abnormalities, but also colonic aganglionosis, carries a mutation in the gene coding for endothelin 3 (Edn3), the ligand for the receptor protein encoded by EDNRB. Here, we describe a mutation of the human gene for endothelin 3 (EDN3), homozygously present in a patient with a combined Waardenburg syndrome type 2 (WS2) and HSCR phenotype (Shah-Waardenburg syndrome). The mutation, Cys159Phe, in exon 3 in the ET-3 like domain of EDN3, presumably affects the proteolytic processing of the preproendothelin to the mature peptide EDN3. The patient's parents were first cousins. A previous child in this family had been diagnosed with a similar combination of HSCR, depigmentation and deafness. Depigmentation and deafness were present in other relatives. Moreover, we present a further indication for the involvement of EDNRB in HSCR by reporting a novel mutation detected in one of 40 unselected HSCR patients.

Focal shift and faculae dimension of focused flat beam propagating in turbulent atmosphere

International Nuclear Information System (INIS)

Zhang Jianzhu; Li Youkuan; Zhang Feizhou; An Jianzhu

2011-01-01

Through theoretic analysis and numerical simulation,the focal shift of a focused flat beam propagating in turbulent atmosphere is studied. When a focused flat beam propagates in turbulent atmosphere, the effect of turbulence will induce the focal spot to move toward the transmitter. The turbulence is stronger and the diameter of transmitter is smaller, the measure of focal shift is larger. When adjusting the focus of transmitter and letting the focal spot of beam locate on detector, the laser intensity received by detector is not the strongest. The laser intensity will be the strongest if the focus of transmitter equals to the distance from transmitter to detector. (authors)

Chronic Fluoxetine Induces Activity Changes in Recovery From Poststroke Anxiety, Depression, and Cognitive Impairment.

Science.gov (United States)

Vahid-Ansari, Faranak; Albert, Paul R

2018-01-01

Poststroke depression (PSD) is a common outcome of stroke that limits recovery and is only partially responsive to chronic antidepressant treatment. In order to elucidate changes in the cortical-limbic circuitry associated with PSD and its treatment, we examined a novel mouse model of persistent PSD. Focal endothelin-1-induced ischemia of the left medial prefrontal cortex (mPFC) in male C57BL6 mice resulted in a chronic anxiety and depression phenotype. Here, we show severe cognitive impairment in spatial learning and memory in the stroke mice. The behavioral and cognitive phenotypes were reversed by chronic (4-week) treatment with fluoxetine, alone or with voluntary exercise (free-running wheel), but not by exercise alone. To assess chronic cellular activation, FosB + cells were co-labeled for markers of glutamate/pyramidal (VGluT1-3/CaMKIIα), γ-aminobutyric acid (GAD67), and serotonin (TPH). At 6 weeks poststroke versus sham (or 4 days poststroke), left mPFC stroke induced widespread FosB activation, more on the right (contralesional) than on the left side. Stroke activated glutamate cells of the mPFC, nucleus accumbens, amygdala, hippocampus, and raphe serotonin neurons. Chronic fluoxetine balanced bilateral neuronal activity, reducing total FosB and FosB/CamKII + cells (mPFC, nucleus accumbens), and unlike exercise, increasing FosB/GAD67 + cells (septum, amygdala) or both (hippocampus, raphe). In summary, chronic antidepressant but not exercise mediates recovery in this unilateral ischemic PSD model that is associated with region-specific reversal of stroke-induced pyramidal cell hyperactivity and increase in γ-aminobutyric acidergic activity. Targeted brain stimulation to restore brain activity could provide a rational approach for treating clinical PSD.

Co-inhibition of Angiotensin II Receptor and Endothelin-1 Attenuates Renal Injury in Unilateral Ureteral Obstructed Mice

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Yoon-Kyung Chang

2016-07-01

Full Text Available Background/Aims: Both endothelin-1 (ET-1 and the renin-angiotensin system (RAS may play important roles in renal fibrosis in the obstructed kidney. However, there have been few clear demonstrations of a relationship between their activation and additive or synergistic roles in renal fibrosis. We investigated the protective roles and relationship between renal RAS and ET-1 in unilateral ureteral obstruction (UUO mice. Methods: 8-week-old male C57BL/6 mice were divided into seven groups: sham, bosentan+sham, valsartan+sham, vehicle+UUO, bosentan+UUO, valsartan+UUO, and valsartan+bosentan+UUO. Valsartan and bosentan were administered orally using an NG tube (valsartan 10 mg/kg/day, bosentan 100 mg/kg/day for 8 days, after which the molecular and structural kidney parameters were evaluated. Bosentan treatment elevated plasma renin activity, renal renin, and AT1R expression in UUO mice. Results: Although valsartan decreased plasma ET-1 in these mice, it did not affect ET(A or ET(B in their kidneys. Co-treatment with valsartan and bosentan decreased ET-1 in these mice compared to the single treatments. Bosentan, but not valsartan, elevated eNOS expression in their kidneys. Co-treatment with valsartan and bosentan reduced TGF-β, α-SMA, and collagen IV expression, and the Masson's trichrome stained area in their kidneys. Conclusions: Bosentan and valsartan acted complementarily, and co-treatment with both drugs had an additive protective effect against renal fibrosis.

Ginsenoside Rb1 Attenuates Agonist-Induced Contractile Response via Inhibition of Store-Operated Calcium Entry in Pulmonary Arteries of Normal and Pulmonary Hypertensive Rats

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Rui-Xing Wang

2015-03-01

Full Text Available Background: Pulmonary hypertension (PH is characterized by sustained vasoconstriction, enhanced vasoreactivity and vascular remodeling, which leads to right heart failure and death. Despite several treatments are available, many forms of PH are still incurable. Ginsenoside Rb1, a principle active ingredient of Panax ginseng, exhibits multiple pharmacological effects on cardiovascular system, and suppresses monocrotaline (MCT-induced right heart hypertrophy. However, its effect on the pulmonary vascular functions related to PH is unknown. Methods: We examined the vasorelaxing effects of ginsenoside Rb1 on endothelin-1 (ET-1 induced contraction of pulmonary arteries (PAs and store-operated Ca2+ entry (SOCE in pulmonary arterial smooth muscle cells (PASMCs from chronic hypoxia (CH and MCT-induced PH. Results: Ginsenoside Rb1 elicited concentration-dependent relaxation of ET-1-induced PA contraction. The vasorelaxing effect was unaffected by nifedipine, but abolished by the SOCE blocker Gd3+. Ginsenoside Rb1 suppressed cyclopiazonic acid (CPA-induced PA contraction, and CPA-activated cation entry and Ca2+ transient in PASMCs. ET-1 and CPA-induced contraction, and CPA-activated cation entry and Ca2+ transients were enhanced in PA and PASMCs of CH and MCT-treated rats; the enhanced responses were abolished by ginsenoside Rb1. Conclusion: Ginsenoside Rb1 attenuates ET-1-induced contractile response via inhibition of SOCE, and it can effectively antagonize the enhanced pulmonary vasoreactivity in PH.

Role of endothelin receptor activation in secondary pulmonary hypertension in awake swine after myocardial infarction

NARCIS (Netherlands)

B. Houweling (Birgit); D. Merkus (Daphne); O. Sorop (Oana); F. Boomsma (Frans); D.J.G.M. Duncker (Dirk)

2006-01-01

textabstractWe previously observed that pulmonary hypertension secondary to myocardial infarction (MI) in swine is characterized by elevated plasma endothelin (ET) levels and pulmonary vascular resistance (PVR). Consequently, we tested the hypothesis that an increased ET-mediated vasoconstrictor

Brain Natriuretic Peptide, Atrial Natriuretic Peptide and Endothelin-1 response to peak exercise in patients with coronary artery disease and correlation with myocardial perfusion scintigraphy abnormalities

International Nuclear Information System (INIS)

Erbas, B.; Ergun, E.; Koray, Z.; Kabakci, G.; Yildirir, A.; Kes, S.

2002-01-01

Aim: Plasma Brain Natriuretic Peptide (BNP) has been known as a promising marker of ventricular dysfunction in cardiac patients. There are conflicting reports about its response to exercise testing. Therefore, this study was performed to investigate the exercise induced changes in BNP, Atrial Natriuretic Peptide (ANP) and Endothelin-1 (E) levels and their correlation with perfusion abnormalities on myocardial perfusion scintigraphy (MPS). Materials and Methods: Study group consisted of 35 patients (mean age=53.9+11.8) who underwent MPS with suspicion or diagnosis of coronary artery disease. Plasma levels of BNP, ANP, and E were measured at rest and after symptom-limited ergometry. Patients were divided into two groups according to the presence of perfusion abnormality (i.e. ischemia or infarction) on MPS. Results: BNP, ANP and E levels did not change significantly with exercise, however baseline levels of BNP, ANP levels and peak-exercise level of BNP in patients with perfusion abnormalities were significantly higher. Hypertensive patients with or without perfusion abnormalities had higher baseline BNP, ANP levels, and peak-exercise BNP levels compared to normotensives. BNP levels at rest and after exercise had a significant correlation with age (r=0.57, p=0.04; r=0.58, p=0.04), as well as baseline ANP values (r=0.37, p=0.033). Highest baseline BNP, ANP and exercise BNP levels were observed in patients with infarction. Conclusion: Exercise-testing did not induce significant changes in plasma levels of BNP, ANP and E. Higher BNP levels had correlation with the presence of ischemia, infarction and hypertension, as well as, increasing age

Imaging evidence for endothelin ETA/ETB receptor heterodimers in isolated rat mesenteric resistance arteries

DEFF Research Database (Denmark)

Kapsokalyvas, Dimitrios; Schiffers, Paul M H; Maij, Nathan

2014-01-01

AIMS: In engineered cells, endothelin ETA and ETB receptors can heterodimerize. We tested whether this can also be observed in native tissue. MAIN METHODS: Rat mesenteric resistance arteries (rMRA) were maintained in organ culture for 24h to upregulate ETB-mediated contractions in addition to the...

Focal retinal phlebitis.

Science.gov (United States)

Hoang, Quan V; Freund, K Bailey; Klancnik, James M; Sorenson, John A; Cunningham, Emmett T; Yannuzzi, Lawrence A

2012-01-01

To report three cases of solitary, focal retinal phlebitis. An observational case series. Three eyes in three patients were noted to have unilateral decreased vision, macular edema, and a focal retinal phlebitis, which was not at an arteriovenous crossing. All three patients developed a branch retinal vein occlusion at the site of inflammation. These patients had no other evidence of intraocular inflammation, including vitritis, retinitis, retinal vasculitis, or choroiditis, nor was there any systemic disorder associated with inflammation, infection, or coagulation identified. Focal retinal phlebitis appears to be an uncommon and unique entity that produces macular edema and ultimately branch retinal vein occlusion. In our patients, the focal phlebitis and venous occlusion did not occur at an arteriovenous crossing, which is the typical site for branch retinal venous occlusive disease. This suggests that our cases represent a distinct clinical entity, which starts with a focal abnormality in the wall of a retinal venule, resulting in surrounding exudation and, ultimately, ends with branch retinal vein occlusion.

Advances in direct radiographic magnification technique: First studies with a 1μ focal spot tube

International Nuclear Information System (INIS)

Huettenbrink, K.B.; Schadel, A.

1986-01-01

A direct radiographic enlargement technique mainly depends on the size of the focal spot. Up to now, its reduction was limited for physical reasons; therefore only minor degrees of magnification were applicable. With the new 1 μ focal spot tube, structures of microscopic dimensions can be visualized for the first time in a direct radiographic magnification of up to 100 diameters. First studies in isolated middle ear ossicles and a phantom soft-tissue-skull are demonstrated. Clinical usefullness seems to be limited, whereas its application for experimental research looks promising. (orig.) [de

LPS from Porphyromonas gingivalis increases the sensitivity of contractile response mediated by endothelin-B (ET(B)) receptors in cultured endothelium-intact rat coronary arteries

DEFF Research Database (Denmark)

Ghorbani, Bahareh; Holmstrup, Palle; Edvinsson, Lars

2010-01-01

The purpose of our study was to examine if lipopolysaccharide (LPS) from Porphyromonas gingivalis (P.g.) modifies the vasomotor responses to Endothelin-1 (ET-1) and Sarafotoxin 6c (S6c) in rat coronary arteries. The arteries were studied directly or following organ culture for 24h in absence...

Theory of the mechanical response of focal adhesions to shear flow

International Nuclear Information System (INIS)

Biton, Y Y; Safran, S A

2010-01-01

The response of cells to shear flow is primarily determined by the asymmetry of the external forces and moments that are sensed by each member of a focal adhesion pair connected by a contractile stress fiber. In the theory presented here, we suggest a physical model in which each member of such a pair of focal adhesions is treated as an elastic body subject to both a myosin-activated contractile force and the shear stress induced by the external flow. The elastic response of a focal adhesion complex is much faster than the active cellular processes that determine the size of the associated focal adhesions and the direction of the complex relative to the imposed flow. Therefore, the complex attains its mechanical equilibrium configuration which may change because of the cellular activity. Our theory is based on the experimental observation that focal adhesions modulate their cross-sectional area in order to attain an optimal shear. Using this assumption, our elastic model shows that such a complex can passively change its orientation to align parallel to the direction of the flow.

Optimization of a Clinically Relevant Model of White Matter Stroke in Mice: Histological and Functional Evidences

Science.gov (United States)

Ahmad, Abdullah S.; Satriotomo, Irawan; Fazal, Jawad A.; Nadeau, Stephen E.; Doré, Sylvain

2015-01-01

Background and Purpose White matter (WM) injury during stroke increases the risk of disability and gloomy prognosis of post-stroke rehabilitation. However, modeling of WM loss in rodents has proven to be challenging. Methods We report improved WM injury models in male C57BL/6 mice. Mice were given either endothelin-1 (ET-1) or L-N5-(1-iminoethyl)ornitine (L-NIO) into the periventricular white matter (PVWM), in the corpus callosum (CC), or in the posterior limb of internal capsule (PLIC). Anatomical and functional outcomes were quantified on day 7 post injection. Results Injection of ET-1 or L-NIO caused a small focal lesion in the injection site in the PVWM. No significant motor function deficits were observed in the PVWM lesion model. We next targeted the PLIC by using single or double injections of L-NIO and found that this strategy induced small focal infarction. Interestingly, injection of L-NIO in the PLIC also resulted in gliosis, and significant motor function deficits. Conclusions By employing different agents, doses, and locations, this study shows the feasibility of inducing brain WM injury accompanied with functional deficits in mice. Selective targeting of the injury location, behavioral testing, and the agents chosen to induce WM injury are all keys to successfully develop a mouse model and subsequent testing of therapeutic interventions against WM injury. PMID:27512724

[Molecular mechanism for ET-1-induced insulin resistance in skeletal muscle cells].

Science.gov (United States)

Horinouchi, Takahiro; Mazaki, Yuichi; Terada, Koji; Miwa, Soichi

2018-01-01

Insulin resistance is a condition where the sensitivity to insulin of the tissues expressing insulin receptor (InsR) is decreased due to a functional disturbance of InsR-mediated intracellular signaling. Insulin promotes the entry of glucose into the tissues and skeletal muscle is the most important tissue responsible for the insulin's action of decreasing blood glucose levels. Endothelin-1 (ET-1), a potent vasoconstrictor and pro-inflammatory peptide, induces insulin resistance through a direct action on skeletal muscle. However, the signaling pathways of ET-1-induced insulin resistance in skeletal muscle remain unclear. Here we show molecular mechanism underlying the inhibitory effect of ET-1 on insulin-stimulated Akt phosphorylation and glucose uptake in myotubes of rat L6 skeletal muscle cell line. mRNA expression levels of differentiation marker genes, MyoD and myogenin, were increased during L6 myoblasts differentiation into myotubes. Some of myotubes possessed the ability to spontaneously contract. In myotubes, insulin promoted Akt phosphorylation at Thr 308 and Ser 473 , and [ 3 H]-labelled 2-deoxy-D-glucose ([ 3 H]2-DG) uptake. The insulin-facilitated Akt phosphorylation and [ 3 H]2-DG uptake were inhibited by ET-1. The inhibitory effect of ET-1 was counteracted by blockade of ET type A receptor (ET A R), inhibition of G q/11 protein, and siRNA knockdown of G protein-coupled receptor kinase 2 (GRK2). The exogenously overexpressed GRK2 directly bound to endogenous Akt and their association was facilitated by ET-1. In summary, activation of ET A R with ET-1 inhibits insulin-induced Akt phosphorylation and [ 3 H]2-DG uptake in a G q/11 protein- and GRK2-dependent manner in skeletal muscle. These findings indicate that ET A R and GRK2 are potential targets for insulin resistance.

The effects of changes of plasma endothelin level in patients with hypertension after medication of metoprolol tartrate combined with felodipine

International Nuclear Information System (INIS)

Tao Zhihu; Pan Quan

2011-01-01

Objective: To investigate the clinical efficacy and safety of metoprolol tartrate combined with felodipine sustained-release tablets in treatment of high blood pressure. Methods: Patients were allocated to groups of medication of metoprolol tartrate combined with felodipine (Group A, n=57) and single medication of metoprolol tartrate (Group B, n=60). All patients received daily measurement of blood pressure, heart rate, observation of adverse reactions and detection of the plasma endothelin levels before and after the medication. Results: Compared with Group B after the medication, the therapeutic effect was significant in Group A (P<0.01) and both the plasma endothelin levels and the side effects were much lower(P<0.05, P<0.01, respectively). Conclusion: Metoprolol tartrate combined with sustained release felodipine tablets appears effectively in treatment of hypertension, and the therapeutic effect may be associated with the variation of plasma endothelin levels. In addition, metoprolol in combination sustained release felodipine tablets can counteract the adverse reaction from single dose and is worthy for wide clinical use. (authors)

Focal fatty infiltra- tion and focal fatty sparing of the liver

African Journals Online (AJOL)

Enrique

Department of Radiology. Nelson Mandela School of Health Sciences. Durban. Fig. 1a. Unenhanced CT of the liver in case 1 demonstrates multiple focal low density regions in both lobes of the liver. Region of interest 1 over the fatty left lobe measured 10 HU while region of interest 2 over the right lobe measure 40 HU in.

The effect of serum magnesium levels and serum endothelin-1 levels on bone mineral density in protein energy malnutrition.

Science.gov (United States)

Ozturk, C F; Karakelleoglu, C; Orbak, Z; Yildiz, L

2012-06-01

An inadequate and imbalanced intake of protein and energy results in protein-energy malnutrition (PEM). It is known that bone mineral density and serum magnesium levels are low in malnourished children. However, the roles of serum magnesium and endothelin-1 (ET-1) levels in the pathophysiology of bone mineralization are obscure. Thus, the relationships between serum magnesium and ET-1 levels and the changes in bone mineral density were investigated in this study. There was a total of 32 subjects, 25 of them had PEM and seven were controls. While mean serum ET-1 levels of the children with kwashiorkor and marasmus showed no statistically significant difference, mean serum ET-1 levels of both groups were significantly higher than that of the control group. Serum magnesium levels were lower than normal value in 9 (36%) of 25 malnourished children. Malnourished children included in this study were divided into two subgroups according to their serum magnesium levels. While mean serum ET-1 levels in the group with low magnesium levels were significantly higher than that of the group with normal magnesium levels (p malnutrition. Our study suggested that lower magnesium levels and higher ET-1 levels might be important factors in changes of bone mineral density in malnutrition. We recommend that the malnourished patients, especially with hypomagnesaemia, should be treated with magnesium early.

Focal myositis

International Nuclear Information System (INIS)

Galloway, H.R.; Dahlstrom, J.E.; Bennett, G.M.

2001-01-01

Focal myositis is a rare, benign focal inflammation of muscle. The lesion often presents as a mass that may be mistaken for a soft tissue sarcoma. This report describes the MRI and histopathological features of a case and illustrates how the diagnosis may be suspected on the basis of the MR findings. Copyright (2001) Blackwell Science Pty Ltd

Noninvasive transcranial focal stimulation via tripolar concentric ring electrodes lessens behavioral seizure activity of recurrent pentylenetetrazole administrations in rats.

Science.gov (United States)

Makeyev, Oleksandr; Luna-Munguía, Hiram; Rogel-Salazar, Gabriela; Liu, Xiang; Besio, Walter G

2013-05-01

Epilepsy affects approximately 1% of the world population. Antiepileptic drugs are ineffective in approximately 30% of patients and have side effects. We have been developing a noninvasive transcranial focal electrical stimulation with our novel tripolar concentric ring electrodes as an alternative/complementary therapy for seizure control. In this study we demonstrate the effect of focal stimulation on behavioral seizure activity induced by two successive pentylenetetrazole administrations in rats. Seizure onset latency, time of the first behavioral change, duration of seizure, and maximal seizure severity score were studied and compared for focal stimulation treated (n = 9) and control groups (n = 10). First, we demonstrate that no significant difference was found in behavioral activity for focal stimulation treated and control groups after the first pentylenetetrazole administration. Next, comparing first and second pentylenetetrazole administrations, we demonstrate there was a significant change in behavioral activity (time of the first behavioral change) in both groups that was not related to focal stimulation. Finally, we demonstrate focal stimulation provoking a significant change in seizure onset latency, duration of seizure, and maximal seizure severity score. We believe that these results, combined with our previous reports, suggest that transcranial focal stimulation may have an anticonvulsant effect.

Obligatory Role of Intraluminal O2− in Acute Endothelin-1 and Angiotensin II Signaling to Mediate Endothelial Dysfunction and MAPK Activation in Guinea-Pig Hearts

Directory of Open Access Journals (Sweden)

Emilia Wojtera

2014-10-01

Full Text Available We hypothesized that, due to a cross-talk between cytoplasmic O2−-sources and intraluminally expressed xanthine oxidase (XO, intraluminal O2− is instrumental in mediating intraluminal (endothelial dysfunction and cytosolic (p38 and ERK1/2 MAPKs phosphorylation manifestations of vascular oxidative stress induced by endothelin-1 (ET-1 and angiotensin II (AT-II. Isolated guinea-pig hearts were subjected to 10-min agonist perfusion causing a burst of an intraluminal O2−. ET-1 antagonist, tezosentan, attenuated AT-II-mediated O2−, indicating its partial ET-1 mediation. ET-1 and Ang-T (AT-II + tezosentan triggered intraluminal O2−, endothelial dysfunction, MAPKs and p47phox phosphorylation, and NADPH oxidase (Nox and XO activation. These effects were: (i prevented by blocking PKC (chelerythrine, Nox (apocynin, mitochondrial ATP-dependent K+ channel (5-HD, complex II (TTFA, and XO (allopurinol; (ii mimicked by the activation of Nox (NADH; and mitochondria (diazoxide, 3-NPA and (iii the effects by NADH were prevented by 5-HD, TTFA and chelerythrine, and those by diazoxide and 3-NPA by apocynin and chelerythrine, suggesting that the agonists coactivate Nox and mitochondria, which further amplify their activity via PKC. The effects by ET-1, Ang-T, NADH, diazoxide, and 3-NPA were opposed by blocking intraluminal O2− (SOD and XO, and were mimicked by XO activation (hypoxanthine. Apocynin, TTFA, chelerythrine, and SOD opposed the effects by hypoxanthine. In conclusion, oxidative stress by agonists involves cellular inside-out and outside-in signaling in which Nox-mitochondria-PKC system and XO mutually maintain their activities via the intraluminal O2−.

Focal pancreatic enlargement: differentiation between pancreatic adenocarcinoma and focal pancreatitis on CT and ERCP

International Nuclear Information System (INIS)

Kim, Eun Kyung; Kim, Ki Whang; Lee, Jong Tae; Kim, Hee Soo; Yoo, Hyung Sik; Yu, Jeong Sik; Yoon, Sang Wook

1995-01-01

To differentiate the pancreatic adenocarcinoma from focal pancreatitis on CT and ERCP in cases of focal pancreatic enlargement. We analysed CT findings of 66 patients of pancreatic adenocarcinoma (n = 45) or focal pancreatitis (n = 21) with respect to size, density, calcification, pancreatic or biliary duct dilatation, fat plane obliteration around the vessels, direction of retroperitoneal extension, lymphadenopathy, pseudocyst formation and atrophy of pancreas. ERCP available in 48 patients were analysed in respect to morphologic appearance of CBD and pancreatic duct, and distance between the two ducts. The patients in focal pancreatitis were younger with more common history of alcohol drinking. There was no statistical difference in calcifications of the mass (18% in the adenocarcinoma, 33% in the focal pancreatitis), but a tendency of denser, larger number of calcifications was noted in focal pancreatitis. The finding of fat plane obliteration around the vessels were more common in pancreatic adenocarcinoma, and fascial thickenings were more prominent in focal pancreatitis, although not statistically significant. On ERCP, there were no differential points of CBD, pancreatic duct morphology, but distance between the two ducts at the lesion center was more wider in focal pancreatitis. Differentiating focal pancreatitis from pancreatic adenocarcinoma is difficult. However, we should consider the possibility of focal pancreatitis in cases of patients with young age, having alcoholic history in association with CT findings of large numbers of and dense calcifications, and ERCP findings of prominent separation of two duct at the lesion center

In vivo experimental stroke and in vitro organ culture induce similar changes in vasoconstrictor receptors and intracellular calcium handling in rat cerebral arteries

DEFF Research Database (Denmark)

Povlsen, Gro Klitgaard; Waldsee, Roya; Ahnstedt, Hilda

2012-01-01

Cerebral arteries subjected to different types of experimental stroke upregulate their expression of certain G-protein-coupled vasoconstrictor receptors, a phenomenon that worsens the ischemic brain damage. Upregulation of contractile endothelin B (ET(B)) and 5-hydroxytryptamine 1B (5-HT(1B......)) receptors has been demonstrated after subarachnoid hemorrhage and global ischemic stroke, but the situation is less clear after focal ischemic stroke. Changes in smooth muscle calcium handling have been implicated in different vascular diseases but have not hitherto been investigated in cerebral arteries...... and extracellular sources, whereas 5-HT(1B) receptor-mediated contraction was solely dependent on extracellular calcium. Organ culture and stroke increased basal intracellular calcium levels in MCA smooth muscle cells and decreased the expression of inositol triphosphate receptor and transient receptor potential...

Clinical significance of changes of plasma endothelin vasoactive factors (ET and NO) as well as serum related interleukin (IL-6 and IL-8) levels in patients with pregnancy induced hypertension (PIH)

International Nuclear Information System (INIS)

Chen Ying

2009-01-01

Objective: To investigate the clinical etiological significance of changes of plasma endothelin (ET) and nitric oxide (NO) as well as serum interleukin-6 (IL-6) and interleukin-8 (IL-8) levels in patients with pregnancy induced hypertension. Methods: Plasma ET (with RIA), NO (with biochemistry) and serum IL-6, IL-8 (with RIA) levels were measured in 32 pregnant women with PIH, 35 normal pregnant women without PIH and 35 non-pregnant women (as controls). Results: The plasma ET, NO level were significantly higher in normal pregnant women than those in the non-pregnant women controls, while serum levels of IL-6 and IL-8 levels were only slightly higher without significance (P>0.05). Before treatment, the blood ET, IL-6 and IL- 8 levels were significantly higher in patients with pregnancy induced hypertension than those in the control (P<0.01), while plasma levels of NO were significantly decreased (P<0.01), Two weeks after treatment, the plasma ET, NO and serum IL-6 and IL-8 levels were markedly corrected with no significantly differences from those in controls. The ET levels and serum IL-6, IL-8 levels were mutually positively correlated (r=0.6097, 0.7213, P<0.01). Conclusion: Determination of changes of plasma ET and NO, serum IL-6 and IL-8 levels in patients with pregnancy induced hypertension was helpful for outcome prediction. (authors)

A case of pathological rib fractures: focal osteolysis or osteoporosis?

Science.gov (United States)

Vrbanić, T S L; Novak, S; Sestan, B; Tudor, A; Gulan, G

2008-03-01

This paper reports on a unique, previously unreported, successful outcome in the case of a patient with focal osteolytic lesions of the ribs as a first sign of osteoporosis. The lesions were detected by chance after acute cough-induced rib fractures were seen on plain chest radiographs. The diagnosis had to be approached as a diagnosis of exclusion since known causes of the osteolytic process had to be eliminated. The authors describe multiple focal osteolytic lesions with rib fractures appearing in a pattern that could be confused with metastases. Laboratory results were normal. Final diagnosis was based on plain radiography, bone scan and bone densitometry. Pharmacomedical treatments for osteoporosis were applied. The patient was observed between the year 2000 and 2005. Five years later radiological and bone scintigraphy revealed resolution of the lesion. We conclude that osteoporosis should be included in the differential diagnosis of asymptomatic focal osteolysis of the ribs with rib fractures as a complication of acute cough. The case suggests that focal osteolytic lesions of the ribs may regress over time and become scintigraphically inactive.

The dispersion-focalization theory of sound systems

Science.gov (United States)

Schwartz, Jean-Luc; Abry, Christian; Boë, Louis-Jean; Vallée, Nathalie; Ménard, Lucie

2005-04-01

The Dispersion-Focalization Theory states that sound systems in human languages are shaped by two major perceptual constraints: dispersion driving auditory contrast towards maximal or sufficient values [B. Lindblom, J. Phonetics 18, 135-152 (1990)] and focalization driving auditory spectra towards patterns with close neighboring formants. Dispersion is computed from the sum of the inverse squared inter-spectra distances in the (F1, F2, F3, F4) space, using a non-linear process based on the 3.5 Bark critical distance to estimate F2'. Focalization is based on the idea that close neighboring formants produce vowel spectra with marked peaks, easier to process and memorize in the auditory system. Evidence for increased stability of focal vowels in short-term memory was provided in a discrimination experiment on adult French subjects [J. L. Schwartz and P. Escudier, Speech Comm. 8, 235-259 (1989)]. A reanalysis of infant discrimination data shows that focalization could well be the responsible for recurrent discrimination asymmetries [J. L. Schwartz et al., Speech Comm. (in press)]. Recent data about children vowel production indicate that focalization seems to be part of the perceptual templates driving speech development. The Dispersion-Focalization Theory produces valid predictions for both vowel and consonant systems, in relation with available databases of human languages inventories.

Hydrostatic pressure and shear stress affect endothelin-1 and nitric oxide release by endothelial cells in bioreactors.

Science.gov (United States)

Vozzi, Federico; Bianchi, Francesca; Ahluwalia, Arti; Domenici, Claudio

2014-01-01

Abundant experimental evidence demonstrates that endothelial cells are sensitive to flow; however, the effect of fluid pressure or pressure gradients that are used to drive viscous flow is not well understood. There are two principal physical forces exerted on the blood vessel wall by the passage of intra-luminal blood: pressure and shear. To analyze the effects of pressure and shear independently, these two stresses were applied to cultured cells in two different types of bioreactors: a pressure-controlled bioreactor and a laminar flow bioreactor, in which controlled levels of pressure or shear stress, respectively, can be generated. Using these bioreactor systems, endothelin-1 (ET-1) and nitric oxide (NO) release from human umbilical vein endothelial cells were measured under various shear stress and pressure conditions. Compared to the controls, a decrease of ET-1 production by the cells cultured in both bioreactors was observed, whereas NO synthesis was up-regulated in cells under shear stress, but was not modulated by hydrostatic pressure. These results show that the two hemodynamic forces acting on blood vessels affect endothelial cell function in different ways, and that both should be considered when planning in vitro experiments in the presence of flow. Understanding the individual and synergic effects of the two forces could provide important insights into physiological and pathological processes involved in vascular remodeling and adaptation. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Transparent meta-analysis: does aging spare prospective memory with focal vs. non-focal cues?

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Bob Uttl

Full Text Available BACKGROUND: Prospective memory (ProM is the ability to become aware of a previously-formed plan at the right time and place. For over twenty years, researchers have been debating whether prospective memory declines with aging or whether it is spared by aging and, most recently, whether aging spares prospective memory with focal vs. non-focal cues. Two recent meta-analyses examining these claims did not include all relevant studies and ignored prevalent ceiling effects, age confounds, and did not distinguish between prospective memory subdomains (e.g., ProM proper, vigilance, habitual ProM (see Uttl, 2008, PLoS ONE. The present meta-analysis focuses on the following questions: Does prospective memory decline with aging? Does prospective memory with focal vs. non-focal cues decline with aging? Does the size of age-related declines with focal vs. non-focal cues vary across ProM subdomains? And are age-related declines in ProM smaller than age-related declines in retrospective memory? METHODS AND FINDINGS: A meta-analysis of event-cued ProM using data visualization and modeling, robust count methods, and conventional meta-analysis techniques revealed that first, the size of age-related declines in ProM with both focal and non-focal cues are large. Second, age-related declines in ProM with focal cues are larger in ProM proper and smaller in vigilance. Third, age-related declines in ProM proper with focal cues are as large as age-related declines in recall measures of retrospective memory. CONCLUSIONS: The results are consistent with Craik's (1983 proposal that age-related declines on ProM tasks are generally large, support the distinction between ProM proper vs. vigilance, and directly contradict widespread claims that ProM, with or without focal cues, is spared by aging.

Chronic endothelin A receptor blockade attenuates contribution of sympathetic nervous system to salt hypertension development in adult but not in young Dahl rats

Czech Academy of Sciences Publication Activity Database

Zicha, Josef; Dobešová, Zdenka; Kuneš, Jaroslav; Vaněčková, Ivana

2012-01-01

Roč. 205, č. 1 (2012), s. 124-132 ISSN 1748-1708 R&D Projects: GA MŠk(CZ) 1M0510; GA ČR(CZ) GA305/09/0336; GA AV ČR(CZ) IAA500110902 Institutional research plan: CEZ:AV0Z50110509 Keywords : Endothelin-1 * salt hypertension * Dahl rats Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 4.382, year: 2012

Synchronous inhibitory potentials precede seizure-like events in acute models of focal limbic seizures.

Science.gov (United States)

Uva, Laura; Breschi, Gian Luca; Gnatkovsky, Vadym; Taverna, Stefano; de Curtis, Marco

2015-02-18

Interictal spikes in models of focal seizures and epilepsies are sustained by the synchronous activation of glutamatergic and GABAergic networks. The nature of population spikes associated with seizure initiation (pre-ictal spikes; PSs) is still undetermined. We analyzed the networks involved in the generation of both interictal and PSs in acute models of limbic cortex ictogenesis induced by pharmacological manipulations. Simultaneous extracellular and intracellular recordings from both principal cells and interneurons were performed in the medial entorhinal cortex of the in vitro isolated guinea pig brain during focal interictal and ictal discharges induced in the limbic network by intracortical and brief arterial infusions of either bicuculline methiodide (BMI) or 4-aminopyridine (4AP). Local application of BMI in the entorhinal cortex did not induce seizure-like events (SLEs), but did generate periodic interictal spikes sensitive to the glutamatergic non-NMDA receptor antagonist DNQX. Unlike local applications, arterial perfusion of either BMI or 4AP induced focal limbic SLEs. PSs just ahead of SLE were associated with hyperpolarizing potentials coupled with a complete blockade of firing in principal cells and burst discharges in putative interneurons. Interictal population spikes recorded from principal neurons between two SLEs correlated with a depolarizing potential. We demonstrate in two models of acute limbic SLE that PS events are different from interictal spikes and are sustained by synchronous activation of inhibitory networks. Our findings support a prominent role of synchronous network inhibition in the initiation of a focal seizure. Copyright © 2015 the authors 0270-6474/15/353048-08$15.00/0.

Comprehensive Survey on Improved Focality and Penetration Depth of Transcranial Magnetic Stimulation Employing Multi-Coil Arrays

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Xile Wei

2017-11-01

Full Text Available Multi-coil arrays applied in transcranial magnetic stimulation (TMS are proposed to accurately stimulate brain tissues and modulate neural activities by an induced electric field (EF. Composed of numerous independently driven coils, a multi-coil array has alternative energizing strategies to evoke EFs targeting at different cerebral regions. To improve the locating resolution and the stimulating focality, we need to fully understand the variation properties of induced EFs and the quantitative control method of the spatial arrangement of activating coils, both of which unfortunately are still unclear. In this paper, a comprehensive analysis of EF properties was performed based on multi-coil arrays. Four types of planar multi-coil arrays were used to study the relationship between the spatial distribution of EFs and the structure of stimuli coils. By changing coil-driven strategies in a basic 16-coil array, we find that an EF induced by compactly distributed coils decays faster than that induced by dispersedly distributed coils, but the former has an advantage over the latter in terms of the activated brain volume. Simulation results also indicate that the attenuation rate of an EF induced by the 36-coil dense array is 3 times and 1.5 times greater than those induced by the 9-coil array and the 16-coil array, respectively. The EF evoked by the 36-coil dispense array has the slowest decay rate. This result demonstrates that larger multi-coil arrays, compared to smaller ones, activate deeper brain tissues at the expense of decreased focality. A further study on activating a specific field of a prescribed shape and size was conducted based on EF variation. Accurate target location was achieved with a 64-coil array 18 mm in diameter. A comparison between the figure-8 coil, the planar array, and the cap-formed array was made and demonstrates an improvement of multi-coil configurations in the penetration depth and the focality. These findings suggest

Comprehensive Survey on Improved Focality and Penetration Depth of Transcranial Magnetic Stimulation Employing Multi-Coil Arrays.

Science.gov (United States)

Wei, Xile; Li, Yao; Lu, Meili; Wang, Jiang; Yi, Guosheng

2017-11-14

Multi-coil arrays applied in transcranial magnetic stimulation (TMS) are proposed to accurately stimulate brain tissues and modulate neural activities by an induced electric field (EF). Composed of numerous independently driven coils, a multi-coil array has alternative energizing strategies to evoke EFs targeting at different cerebral regions. To improve the locating resolution and the stimulating focality, we need to fully understand the variation properties of induced EFs and the quantitative control method of the spatial arrangement of activating coils, both of which unfortunately are still unclear. In this paper, a comprehensive analysis of EF properties was performed based on multi-coil arrays. Four types of planar multi-coil arrays were used to study the relationship between the spatial distribution of EFs and the structure of stimuli coils. By changing coil-driven strategies in a basic 16-coil array, we find that an EF induced by compactly distributed coils decays faster than that induced by dispersedly distributed coils, but the former has an advantage over the latter in terms of the activated brain volume. Simulation results also indicate that the attenuation rate of an EF induced by the 36-coil dense array is 3 times and 1.5 times greater than those induced by the 9-coil array and the 16-coil array, respectively. The EF evoked by the 36-coil dispense array has the slowest decay rate. This result demonstrates that larger multi-coil arrays, compared to smaller ones, activate deeper brain tissues at the expense of decreased focality. A further study on activating a specific field of a prescribed shape and size was conducted based on EF variation. Accurate target location was achieved with a 64-coil array 18 mm in diameter. A comparison between the figure-8 coil, the planar array, and the cap-formed array was made and demonstrates an improvement of multi-coil configurations in the penetration depth and the focality. These findings suggest that there is a

Systemic focal epileptogenesis

Energy Technology Data Exchange (ETDEWEB)

Remler, M.P.; Marcussen, W.H.

1986-01-01

Rats that receive radiation to 0.25 cc of one cerebral hemisphere are clinically and electroencephalographically normal until there is a breakdown of the blood-brain barrier (BBB) at 3 to 6 months postradiation. This BBB lesion can be detected by transient focal seizure activity produced by the BBB-excluded systemic convulsant bicuculline methiodide. In two rats the seizure activity induced by this one injection was self-sustaining. In seven of 15 other rats tested, the subsequent administration of repeated 2 mg/kg injections created a chronic focus that continued to spike with great frequency for 3 weeks or more without further administration of any convulsant. In three of eight other rats, implanted minipumps delivering 180 micrograms/h of bicuculline methiodide produced self-sustaining epileptic activity.

“Focal thyroid inferno” on color Doppler ultrasonography: A specific feature of focal Hashimoto's thyroiditis

International Nuclear Information System (INIS)

Fu, Xianshui; Guo, Limei; Zhang, Huabin; Ran, Weiqiang; Fu, Peng; Li, Zhiqiang; Chen, Wen; Jiang, Ling; Wang, Jinrui; Jia, Jianwen

2012-01-01

Purpose: To evaluate color-Doppler features predictive of focal Hashimoto's thyroiditis. Materials and methods: A total of 521 patients with 561 thyroid nodules that underwent surgeries or gun biopsies were included in this study. These nodules were divided into three groups: focal Hashimoto's thyroiditis (104 nodules in 101 patients), benignity other than focal Hashimoto's thyroiditis (73 nodules in 70 patients), and malignancy (358 nodules in 350 patients). On color Doppler sonography, four vascularity types were determined as: hypovascularity, marked internal flow, marked peripheral flow and focal thyroid inferno. The χ 2 test was performed to seek the potential vascularity type with the predictive ability of certain thyroid pathology. Furthermore, the gray-scale features of each nodule were also studied. Results: The vascularity type I (hypovascularity) was more often seen in focal Hashimoto's thyroiditis than other benignity and malignancy (46% vs. 20.5% and 19%). While the type II (marked internal flow) showed the opposite tendency (26.9% [focal Hashimoto's thyroiditis] vs. 45.2% [other benignity] and 52.8% [malignancy]). However, type III (marked peripheral flow) was unable to predict any thyroid pathology. Importantly, type IV (focal thyroid inferno) was exclusive to focal Hashimoto's thyroiditis. All 8 type IV nodules appeared to be solid, hypoechoic, and well-defined. Using “focal thyroid inferno” as an indicator of FHT, the diagnostic sensitivity and specificity were 7.7% and 100% respectively. Conclusions: The vascularity type of “focal thyroid inferno” is specific for focal Hashimoto thyroiditis. Recognition of this particular feature may avoid unnecessary interventional procedures for some solid hypoechoic thyroid nodules suspicious of malignancy.

NF-kappaB signaling mediates vascular smooth muscle endothelin type B receptor expression in resistance arteries

DEFF Research Database (Denmark)

Zheng, Jian-Pu; Zhang, Yaping; Edvinsson, Lars

2010-01-01

Vascular smooth muscle cells (SMC) endothelin type B (ET(B)) receptor upregulation results in strong vasoconstriction and reduction of local blood flow. We hypothesizes that the underlying molecular mechanisms involve transcriptional factor nuclear factor-kappaB (NF-kappaB) pathway. ET(B) recepto...

Influence of specific and non-specific endothelin receptor antagonists on renal morphology in rats with surgical renal ablation.

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Nabokov, A; Amann, K; Wagner, J; Gehlen, F; Münter, K; Ritz, E

1996-03-01

Studies in experimental models of chronic renal failure suggest an important role for the endothelin system in the development of renal scarring. Endothelin receptor (ETR) anatagonists interfere with progression, but it has not been resolved (i) whether this is true for all models of renal damage, (ii) to what extent the effect is modulated by systemic blood pressure and (iii) whether the effect is similar for ETAR and ETA/ETBR antagonists. 5/6 subtotal nephrectomy (SNX) by surgical ablation in male Sprague-Dawley rats. Comparison of ACE inhibitor Trandolapril (0.1 mg/kg/day), ETAR antagonist BMS 182874 (30 mg/kg/day) and ETAR/ETBR antagonist Ro 46-2005 (30 mg/kg/day) by gavage. Duration of the experiment eight weeks. Systolic blood pressure by tail plethysmography. Perfusion fixation of kidneys and morphometric analysis ET-1 and ETA/ETBR by quantitative PCR. SNX caused a significant (P < 0.01) increase of systolic blood pressure (170 +/- 8.6 mmHg) compared to sham operated controls (131 +/- 5.3 mmHg). Blood pressure was significantly (P < 0.001) lower with Trandolapril (128 +/- 5.3 mmHg), but not with BMS 182874 (153 +/- 5.9 mmHg) or Ro 46-2005 (167 +/- 7.6 mmHg). Compared to sham operated rats (0.03 +/- 0.01) glomerulosclerosis index (GSI) was significantly (P < 0.01) higher in the untreated SNX group (0.9 +/- 0.15). Significantly lower GSI was found in Trandolapril treated (0.29 +/- 0.04), BMS 182874 treated (0.36 +/- 0.05), and Ro 46-2005 treated animals (0.45 +/- 0.11). The effect of BMS 182874 was accompanied by lower tubulointerstitial damage index. Mean glomerular volume was dramatically increased (P < 0.001) in SNX rats as compared to sham operated animals. This glomerular enlargement was partially prevented by Trandolapril (P < 0.05), but not by either ETR antagonist. ET-1 mRNA tended to be higher in SNX irrespective of treatment, while ETAR and ETBR mRNA were significantly lower. Both specific (ETAR) and non-specific (ETA/ETBR) endothelin antagonists

Resveratrol prevents high-fructose corn syrup-induced vascular insulin resistance and dysfunction in rats.

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Babacanoglu, C; Yildirim, N; Sadi, G; Pektas, M B; Akar, F

2013-10-01

Dietary intake of fructose and sucrose can cause development of metabolic and cardiovascular disorders. The consequences of high-fructose corn syrup (HFCS), a commonly consumed form of fructose and glucose, have poorly been examined. Therefore, in this study, we investigated whether HFCS intake (10% and 20% beverages for 12 weeks) impacts vascular reactivity to insulin and endothelin-1 in conjunction with insulin receptor substrate-1(IRS-1), endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) mRNA/proteins levels in aorta of rats. At challenge, we tested the effectiveness of resveratrol (28-30 mg/kg body weight/day) on outcomes of HFCS feeding. HFCS (20%) diet feeding increased plasma triglyceride, VLDL, cholesterol, insulin and glucose levels, but not body weights of rats. Impaired nitric oxide-mediated relaxation to insulin (10⁻⁹ to 3×10⁻⁶ M), and enhanced contraction to endothelin-1 (10⁻¹¹ to 10⁻⁸ M) were associated with decreased expression of IRS-1 and eNOS mRNA and protein, but increased expression of iNOS, in aortas of rats fed with HFCS. Resveratrol supplementation restored many features of HFCS-induced disturbances, probably by regulating eNOS and iNOS production. In conclusion, dietary HFCS causes vascular insulin resistance and endothelial dysfunction through attenuating IRS-1 and eNOS expressions as well as increasing iNOS in rats. Resveratrol has capability to recover HFCS-induced disturbances. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Prolonged drug-induced hypothermia in experimental stroke

DEFF Research Database (Denmark)

Johansen, Flemming Fryd; Jørgensen, Henrik Stig; Reith, Jakob

2007-01-01

In experimental and human stroke, hypothermia is strongly related to a favorable outcome. Previous attempts to manipulate the core temperature in focal cerebral ischemia have been based on mechanical cooling. The purpose of the study is to establish a model for long-term drug-induced hypothermia...... in focal ischemia by pharmacological alteration of the central thermoregulatory set-point. We tested the hypothesis that the dopaminergic agonist Talipexole, which induces hypothermia, reduces infarct size. Body temperature was monitored by a radio-pill-implant. Rats had reversible occlusion of the middle...... that the core body temperature was reduced by 1.7 degrees C for 24 hours after MCAO in rats treated with Talipexole. This treatment induced a significant reduction of infarct volume at 7 days after focal ischemia by 47%. We suggest that the reduction in infarct volume is related to drug-induced hypothermia...

Effects of Combined Endothelin A Receptor and Renin-Angiotensin System Blockade on the Course of End-Organ Damage in 5/6 Nephrectomized Ren-2 Hypertensive Rats

Czech Academy of Sciences Publication Activity Database

Vaněčková, Ivana; Kujal, P.; Husková, Z.; Vaňourková, Z.; Vernerová, Z.; Čertíková; Chábová, V.; Škaroupková, P.; Kramer, H. J.; Tesař, V.; Červenka, L.

2012-01-01

Roč. 35, č. 5 (2012), s. 382-392 ISSN 1420-4096 Institutional research plan: CEZ:AV0Z50110509 Keywords : 5/6 nephrectomy * Endothelin receptor type A * AT1 receptor blocker * end-organ damage * hypertension Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.596, year: 2012

Metalloproteinase Inhibition Protects against Reductions in Circulating Adrenomedullin during Lead-induced Acute Hypertension.

Science.gov (United States)

Nascimento, Regina A; Mendes, Gabryella; Possomato-Vieira, Jose S; Gonçalves-Rizzi, Victor Hugo; Kushima, Hélio; Delella, Flavia K; Dias-Junior, Carlos A

2015-06-01

Intoxication with lead (Pb) results in increased blood pressure by mechanisms involving matrix metalloproteinases (MMPs). Recent findings have revealed that MMP type two (MMP-2) seems to cleave vasoactive peptides. This study examined whether MMP-2 and MMP-9 levels/activities increase after acute intoxication with low lead concentrations and whether these changes were associated with increases in blood pressure and circulating endothelin-1 or with reductions in circulating adrenomedullin and calcitonin gene-related peptide (CGRP). Here, we expand previous findings and examine whether doxycycline (a MMPs inhibitor) affects these alterations. Wistar rats received intraperitoneally (i.p.) 1st dose 8 μg/100 g of lead (or sodium) acetate, a subsequent dose of 0.1 μg/100 g to cover daily loss and treatment with doxycycline (30 mg/kg/day) or water by gavage for 7 days. Similar whole-blood lead levels (9 μg/dL) were found in lead-exposed rats treated with either doxycycline or water. Lead-induced increases in systolic blood pressure (from 143 ± 2 to 167 ± 3 mmHg) and gelatin zymography of plasma samples showed that lead increased MMP-9 (but not MMP-2) levels. Both lead-induced increased MMP-9 activity and hypertension were blunted by doxycycline. Doxycycline also prevented lead-induced reductions in circulating adrenomedullin. No significant changes in plasma levels of endothelin-1 or CGRP were found. Lead-induced decreases in nitric oxide markers and antioxidant status were not prevented by doxycycline. In conclusion, acute lead exposure increases blood pressure and MMP-9 activity, which were blunted by doxycycline. These findings suggest that MMP-9 may contribute with lead-induced hypertension by cleaving the vasodilatory peptide adrenomedullin, thereby inhibiting adrenomedullin-dependent lowering of blood pressure. © 2014 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Polymorphisms of the endothelin-A and -B receptor genes in relation to blood pressure and myocardial infarction: the Etude Cas-Témoins sur l'Infarctus du Myocarde (ECTIM) Study.

Science.gov (United States)

Nicaud, V; Poirier, O; Behague, I; Herrmann, S M; Mallet, C; Troesch, A; Bouyer, J; Evans, A; Luc, G; Ruidavets, J B; Arveiler, D; Bingham, A; Tiret, L; Cambien, F

1999-03-01

Endothelin-1 is a potent vasoconstrictor that has also mitogenic properties, stimulating the synthesis and secretion of several vasoactive molecules. There is much evidence to suggest that endothelin-1 might be involved in the pathogenesis of hypertension, atherosclerosis, and ischemic heart disease. Endothelin-1 exerts its effects through at least two receptors, ET(A) and ET(B), which are encoded by different genes and have separate tissue distributions and biologic properties. The objective of this study was to identify polymorphisms of the ET(A) and ET(B) receptor genes and to study their association with myocardial infarction (MI) and blood pressure. The coding regions and 1.3 kb upstream of the ET(A) and ET(B) receptor genes were explored by polymerase chain reaction/single strand conformation polymorphism. Six polymorphisms were found in the ET(A) receptor gene and three in the ET(B) receptor gene. Most of these polymorphisms were frequent. Associations between the detected polymorphisms, blood pressure, and MI were examined in the ECTIM study, a multicenter study comparing 652 patients having survived an MI and 773 controls from Belfast (Northern Ireland) and France. Alleles at the different polymorphic sites were similarly distributed in patients with MI and controls. Allele frequencies were similar in both countries, except for the ET(A)/-231 G allele, which appeared more frequently in France than in Belfast (P < .01). The mean systolic and diastolic blood pressure levels did not significantly differ between genotypes. However, a C/T substitution located in the nontranslated part of exon 8 of the ET(A) receptor gene (ET(A)/EX8nt1363) was associated with pulse pressure (P < .005). These results do not support an involvement of the endothelin receptor genes in a predisposition to MI or the determination of blood pressure levels, but suggest that a polymorphism of the ET(A) receptor gene might influence the pulse pressure. This result will have to be

Reperfusion promotes mitochondrial dysfunction following focal cerebral ischemia in rats.

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Jun Li

Full Text Available BACKGROUND AND PURPOSE: Mitochondrial dysfunction has been implicated in the cell death observed after cerebral ischemia, and several mechanisms for this dysfunction have been proposed. Reperfusion after transient cerebral ischemia may cause continued and even more severe damage to the brain. Many lines of evidence have shown that mitochondria suffer severe damage in response to ischemic injury. The purpose of this study was to observe the features of mitochondrial dysfunction in isolated mitochondria during the reperfusion period following focal cerebral ischemia. METHODS: Male Wistar rats were subjected to focal cerebral ischemia. Mitochondria were isolated using Percoll density gradient centrifugation. The isolated mitochondria were fixed for electron microscopic examination; calcium-induced mitochondrial swelling was quantified using spectrophotometry. Cyclophilin D was detected by Western blotting. Fluorescent probes were used to selectively stain mitochondria to measure their membrane potential and to measure reactive oxidative species production using flow cytometric analysis. RESULTS: Signs of damage were observed in the mitochondrial morphology after exposure to reperfusion. The mitochondrial swelling induced by Ca(2+ increased gradually with the increasing calcium concentration, and this tendency was exacerbated as the reperfusion time was extended. Cyclophilin D protein expression peaked after 24 hours of reperfusion. The mitochondrial membrane potential was decreased significantly during the reperfusion period, with the greatest decrease observed after 24 hours of reperfusion. The surge in mitochondrial reactive oxidative species occurred after 2 hours of reperfusion and was maintained at a high level during the reperfusion period. CONCLUSIONS: Reperfusion following focal cerebral ischemia induced significant mitochondrial morphological damage and Ca(2+-induced mitochondrial swelling. The mechanism of this swelling may be mediated by

Expansive focal cemento-osseous dysplasia.

Science.gov (United States)

Bulut, Emel Uzun; Acikgoz, Aydan; Ozan, Bora; Zengin, Ayse Zeynep; Gunhan, Omer

2012-01-01

To present a case of expansive focal cemento-osseous dysplasia and emphasize the importance of differential diagnosis. Cemento-osseous dysplasia is categorized into three subtypes on the basis of the clinical and radiographic features: Periapical, focal and florid. The focal type exhibits a single site of involvement in any tooth-bearing or edentulous area of the jaws. These lesions are usually asymptomatic; therefore, they are frequently diagnosed incidentally during routine radiographic examinations. Lesions are usually benign, show limited growth, and do not require further surgical intervention, but periodic follow-up is recommended because occasionally, this type of dysplasia progresses into florid osseous dysplasia and simple bone cysts are formed. A 24-year-old female patient was referred to our clinic for swelling in the left edentulous mandibular premolarmolar region and felt discomfort when she wore her prosthetics. She had no pain, tenderness or paresthesia. Clinical examination showed that the swelling in the posterior mandible that was firm, nonfluctuant and covered by normal mucosa. On panoramic radiography and computed tomography, a well defined lesion of approximately 1.5 cm in diameter of mixed density was observed. The swelling increased slightly in size over 2 years making it difficult to use prosthetics and, therefore, the lesion was totally excised under local anesthesia, and surgical specimens were submitted for histopathological examination. The histopathological diagnosis was focal cemento-osseous dysplasia. In the present case, because of the increasing size of the swelling making it difficult to use prosthetics, young age of the patient and localization of the lesion, in the initial examination, cemento-ossifying fibroma was suspected, and the lesion was excised surgically; the histopathological diagnosis confirmed it as focal cemento-osseous dysplasia. We present a case of expansive focal cemento-osseous dysplasia. Differential diagnosis

Differential Impact of Stress Reduction Programs upon Ambulatory Blood Pressure among African American Adolescents: Influences of Endothelin-1 Gene and Chronic Stress Exposure

Directory of Open Access Journals (Sweden)

Mathew J. Gregoski

2012-01-01