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Kala P, Gawrys O, Miklovič M, Vaňourková Z, Škaroupková P, Jíchová Š, Sadowski J, Kompanowska-Jezierska E, Walkowska A, Veselka J, Táborský M, Maxová H, Vaněčková I, Červenka L. Endothelin type A receptor blockade attenuates aorto-caval fistula-induced heart failure in rats with angiotensin II-dependent hypertension. J Hypertens 2023; 41:99-114. [PMID: 36204993 PMCID: PMC9794157 DOI: 10.1097/hjh.0000000000003307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 08/06/2022] [Accepted: 09/07/2022] [Indexed: 02/01/2023]
Abstract
OBJECTIVE Evaluation of the effect of endothelin type A (ET A ) receptor blockade on the course of volume-overload heart failure in rats with angiotensin II-dependent hypertension. METHODS Ren-2 renin transgenic rats (TGR) were used as a model of hypertension. Heart failure was induced by creating an aorto-caval fistula (ACF). Selective ET A receptor blockade was achieved by atrasentan. For comparison, other rat groups received trandolapril, an angiotensin-converting enzyme inhibitor (ACEi). Animals first underwent ACF creation and 2 weeks later the treatment with atrasentan or trandolapril, alone or combined, was applied; the follow-up period was 20 weeks. RESULTS Eighteen days after creating ACF, untreated TGR began to die, and none was alive by day 79. Both atrasentan and trandolapril treatment improved the survival rate, ultimately to 56% (18 of 31 animals) and 69% (22 of 32 animals), respectively. Combined ACEi and ET A receptor blockade improved the final survival rate to 52% (17 of 33 animals). The effects of the three treatment regimens on the survival rate did not significantly differ. All three treatment regimens suppressed the development of cardiac hypertrophy and lung congestion, decreased left ventricle (LV) end-diastolic volume and LV end-diastolic pressure, and improved LV systolic contractility in ACF TGR as compared with their untreated counterparts. CONCLUSION The treatment with ET A receptor antagonist delays the onset of decompensation of volume-overload heart failure and improves the survival rate in hypertensive TGR with ACF-induced heart failure. However, the addition of ET A receptor blockade did not enhance the beneficial effects beyond those obtained with standard treatment with ACEi alone.
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Affiliation(s)
- Petr Kala
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
- Department of Cardiology, University Hospital Motol and 2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Olga Gawrys
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Matúš Miklovič
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Zdenka Vaňourková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Petra Škaroupková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Šárka Jíchová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Janusz Sadowski
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Elzbieta Kompanowska-Jezierska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Agnieszka Walkowska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Josef Veselka
- Department of Cardiology, University Hospital Motol and 2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Miloš Táborský
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc
| | - Hana Maxová
- Department of Pathophysiology, 2nd Faculty of Medicine, Charles University
| | - Ivana Vaněčková
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Luděk Červenka
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc
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Rivera-Gonzalez O, Case CT, Wilson NA, Speed JS, Taylor EB. Endothelin receptor antagonism improves glucose tolerance and adipose tissue inflammation in an experimental model of systemic lupus erythematosus. Am J Physiol Endocrinol Metab 2023; 324:E73-E84. [PMID: 36476039 PMCID: PMC9870584 DOI: 10.1152/ajpendo.00274.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
Endothelin-1 (ET-1) is elevated in patients with systemic lupus erythematosus (SLE), an autoimmune disease characterized by high rates of hypertension, renal injury, and cardiovascular disease. SLE is also associated with an increased prevalence of obesity and insulin resistance compared to the general population. In the present study, we tested the hypothesis that elevated ET-1 in SLE contributes to obesity and insulin resistance. For these studies, we used the NZBWF1 mouse model of SLE, which develops obesity and insulin resistance on a normal chow diet. To test this hypothesis, we treated control (NZW) and SLE (NZBWF1) mice with vehicle, atrasentan (ETA receptor antagonist, 10 mg/kg/day), or bosentan (ETA/ETB receptor antagonist, 100 mg/kg/day) for 4 wk. Neither treatment impacted circulating immunoglobulin levels, but treatment with bosentan lowered anti-dsDNA IgG levels, a marker of SLE disease activity. Treatment with atrasentan and bosentan decreased glomerulosclerosis, and atrasentan lowered renal T-cell infiltration. Body weight was lower in SLE mice treated with atrasentan or bosentan. Endothelin receptor antagonism also improved hyperinsulinemia, homeostatic model assessment for insulin resistance, and glucose tolerance in SLE mice. Adipose tissue inflammation was also improved by endothelin receptor blockade. Taken together, these data suggest a potential therapeutic benefit for SLE patients with obesity and insulin resistance.NEW & NOTEWORTHY SLE is an autoimmune disease that is associated with obesity, insulin resistance, and elevated endothelin-1. The present study demonstrated that pharmacological inhibition of endothelin receptors decreased body weight, insulin resistance, and adipose tissue inflammation in a murine model of SLE. The therapeutic potential of endothelin receptor antagonists to treat obesity-related diseases and pathophysiological conditions, such as autoimmune diseases and insulin resistance, has become increasingly clear.
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Affiliation(s)
- Osvaldo Rivera-Gonzalez
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi
| | - Clinton T Case
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi
| | - Natalie A Wilson
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi
| | - Joshua S Speed
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi
| | - Erin B Taylor
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi
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Koomen JV, Stevens J, Bakris G, Correa‐Rotter R, Hou FF, Kitzman DW, Kohan D, Makino H, McMurray JJV, Parving H, Perkovic V, Tobe SW, de Zeeuw D, Heerspink HJL. Inter-individual variability in atrasentan exposure partly explains variability in kidney protection and fluid retention responses: A post hoc analysis of the SONAR trial. Diabetes Obes Metab 2021; 23:561-568. [PMID: 33184931 PMCID: PMC7839558 DOI: 10.1111/dom.14252] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 10/30/2020] [Accepted: 11/05/2020] [Indexed: 12/24/2022]
Abstract
AIM To evaluate whether atrasentan plasma exposure explains between-patient variability in urinary albumin-to-creatinine ratio (UACR) response, a surrogate for kidney protection, and B-type natriuretic peptide (BNP) response, a surrogate for fluid expansion. METHODS Type 2 diabetic patients with chronic kidney disease (n = 4775) received 0.75 mg atrasentan for 6 weeks in the active run-in period. Individual area under the concentration-time-curve (AUC) was estimated using a population pharmacokinetic model. The association between atrasentan AUC, other clinical characteristics, and UACR and BNP response, was estimated using linear regression. RESULTS The median atrasentan AUC was 43.8 ng.h/mL with a large variation among patients (2.5th-97.5th percentiles [P]: 12.6 to 197.5 ng.h/mL). Median UACR change at the end of enrichment was -36.0% and median BNP change was 8.7%, which also varied among patients (UACR, 2.5th-97.5th P: -76.2% to 44.5%; BNP, 2.5th-97.5th P: -71.5% to 300.0%). In the multivariable analysis, higher atrasentan AUC was associated with greater UACR reduction (4.88% per doubling in ng.h/mL [95% confidence interval {CI}: 6.21% to 3.52%], P < .01) and greater BNP increase (3.08% per doubling in ng.h/mL [95% CI: 1.12% to 4.11%], P < .01) independent of estimated glomerular filtration rate, haemoglobin or BNP. Caucasian patients compared with black patients had greater UACR reduction (7.06% [95% CI: 1.38% to 13.07%]) and also greater BNP increase (8.75% [95% CI: 1.65% to 15.35%]). UACR response was not associated with BNP response (r = 0.06). CONCLUSION Atrasentan plasma exposure varied among individual patients and partially explained between-patient variability in efficacy and safety response.
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Affiliation(s)
- Jeroen V. Koomen
- Department of Clinical Pharmacy and PharmacologyUniversity of Groningen, University Medical Center GroningenGroningenthe Netherlands
| | - Jasper Stevens
- Department of Clinical Pharmacy and PharmacologyUniversity of Groningen, University Medical Center GroningenGroningenthe Netherlands
| | - George Bakris
- American Society of Hypertension Comprehensive Hypertension CenterUniversity of Chicago Medicine and Biological SciencesChicagoIllinois
| | | | - Fan Fan Hou
- Division of Nephrology, Nanfang HospitalSouthern Medical University, National Clinical Research Center for Kidney DiseaseGuangzhouChina
| | | | - Donald Kohan
- Division of NephrologyUniversity of Utah Health Sciences CenterSalt Lake CityUtah
| | | | - John J. V. McMurray
- British Heart Foundation Cardiovascular Research CentreUniversity of GlasgowGlasgowUK
| | - Hans‐Henrik Parving
- Department of Medical Endocrinology, RigshospitaletUniversity of CopenhagenCopenhagenDenmark
- Faculty of Health ScienceAarhus UniversityAarhusDenmark
| | - Vlado Perkovic
- George Institute for Global Health and University of New South WalesSydneyNew South WalesAustralia
| | - Sheldon W. Tobe
- Division of Nephrology, Sunnybrook Health Sciences CentreUniversity of Toronto and the Northern Ontario School of MedicineTorontoOntarioCanada
| | - Dick de Zeeuw
- Department of Clinical Pharmacy and PharmacologyUniversity of Groningen, University Medical Center GroningenGroningenthe Netherlands
| | - Hiddo J. L. Heerspink
- Department of Clinical Pharmacy and PharmacologyUniversity of Groningen, University Medical Center GroningenGroningenthe Netherlands
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Liu D, Liu Z. Atrasentan in patients with diabetes and chronic kidney disease. Lancet 2020; 395:269-270. [PMID: 31982064 DOI: 10.1016/s0140-6736(19)33021-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 11/08/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Dongwei Liu
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Zhangsuo Liu
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
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Heerspink HJL, Parving HH, de Zeeuw D. Atrasentan in patients with diabetes and chronic kidney disease - Authors' reply. Lancet 2020; 395:270. [PMID: 31982067 DOI: 10.1016/s0140-6736(19)32995-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 11/08/2019] [Indexed: 11/23/2022]
Affiliation(s)
- Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen 9700 RB, Netherlands.
| | | | - Dick de Zeeuw
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen 9700 RB, Netherlands
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Sepe V, Libetta C. Atrasentan in patients with diabetes and chronic kidney disease. Lancet 2020; 395:269. [PMID: 31982065 DOI: 10.1016/s0140-6736(19)33020-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 11/08/2019] [Indexed: 11/27/2022]
Affiliation(s)
- Vincenzo Sepe
- Unit of Nephrology and Dialysis, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia 27100, Italy.
| | - Carmelo Libetta
- Unit of Nephrology and Dialysis, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia 27100, Italy; Deptartment of Internal Medicine and Medical Therapy, University of Pavia, Pavia, Italy
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Affiliation(s)
- Katherine R Tuttle
- Providence Medical Research Center, Providence Health Care, Spokane, WA 99204, USA; Nephrology Division, Kidney Research Institute and Institute of Translational Health Sciences, University of Washington, Seattle, WA, USA.
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Webb DJ, Coll B, Heerspink HJL, Andress D, Pritchett Y, Brennan JJ, Houser M, Correa-Rotter R, Kohan D, Makino H, Perkovic V, Remuzzi G, Tobe SW, Toto R, Busch R, Pergola P, Parving HH, de Zeeuw D. Longitudinal Assessment of the Effect of Atrasentan on Thoracic Bioimpedance in Diabetic Nephropathy: A Randomized, Double-Blind, Placebo-Controlled Trial. Drugs R D 2018; 17:441-448. [PMID: 28831752 PMCID: PMC5629141 DOI: 10.1007/s40268-017-0201-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background Fluid retention is a common adverse event in patients who receive endothelin (ET) receptor antagonist therapy, including the highly selective ETA receptor antagonist, atrasentan. Objective We performed longitudinal assessments of thoracic bioimpedance in patients with type 2 diabetes mellitus and nephropathy to determine whether a decrease in bioimpedance accurately reflected fluid retention during treatment with atrasentan. Study Design We conducted a randomized, double-blind, placebo-controlled study in 48 patients with type 2 diabetes mellitus and nephropathy who were receiving stable doses of renin angiotensin system inhibitors and diuretics. Methods Patients were randomized 1:1:1 to placebo, atrasentan 0.5 mg, or atrasentan 1.25 mg once daily for 8 weeks. Thoracic bioimpedance, vital signs, clinical exams, and serologies were taken at weeks 1, 2, 4, 6, and 8, with the exception of serum hemoglobin, which was not taken at week 1, and serum brain natriuretic peptide, which was only taken at baseline, week 4, and week 8. Results Alterations in bioimpedance were more often present in those who received atrasentan than in those who received placebo, though overall differences were not statistically significant. Transient declines in thoracic bioimpedance during the first 2 weeks of atrasentan exposure occurred before or during peak increases in body weight and hemodilution (decreased serum hemoglobin). Conclusions We conclude that thoracic bioimpedance did not reflect changes in weight gain or edema with atrasentan treatment in this study. However, the sample size was small, and it may be of interest to explore the use of thoracic bioimpedance in a larger population to understand its potential clinical use in monitoring fluid retention in patients with chronic kidney disease who receive ET receptor antagonists.
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Affiliation(s)
- David J Webb
- Edinburgh Hypertension Excellence Centre, Clinical Pharmacology Unit, University of Edinburgh, E3.22, QMRI, 47 Little France Crescent, Edinburgh, EH16 4TJ, Scotland, UK.
| | | | - Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | | | | | | | | | - Ricardo Correa-Rotter
- National Medical Science and Nutrition Institute Salvador Zubiran, Mexico City, Mexico
| | - Donald Kohan
- University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - Hirofumi Makino
- Okayama University Graduate School of Medicine, Okayama, Japan
| | | | - Giuseppe Remuzzi
- Azienda Ospedaliera Papa Giovanni XXIII and IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy
| | | | - Robert Toto
- University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | | | | | - Dick de Zeeuw
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
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Pena MJ, de Zeeuw D, Andress D, Brennan JJ, Correa-Rotter R, Coll B, Kohan DE, Makino H, Perkovic V, Remuzzi G, Tobe SW, Toto R, Parving HH, Sharma S, Corringham T, Sharma K, Heerspink HJL. The effects of atrasentan on urinary metabolites in patients with type 2 diabetes and nephropathy. Diabetes Obes Metab 2017; 19:749-753. [PMID: 28019071 DOI: 10.1111/dom.12864] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 12/08/2016] [Accepted: 12/21/2016] [Indexed: 01/23/2023]
Abstract
We assessed the effect of atrasentan therapy on a pre-specified panel of 13 urinary metabolites known to reflect mitochondrial function in patients with diabetic kidney disease. This post-hoc analysis was performed using urine samples collected during the RADAR study which was a randomized, double-blind, placebo-controlled trial that tested the effects of atrasentan on albuminuria reduction in patients with type 2 diabetes and nephropathy. At baseline, 4 of the 13 metabolites, quantified by gas-chromatography mass spectrometry, were below detectable levels, and 6 were reduced in patients with eGFR < 60 mL/min/1.73 m2 . After 12 weeks of atrasentan treatment in patients with eGFR < 60 mL/min/1.73 m2 , a single-value index of the metabolites changed by -0.31 (95%CI -0.60 to -0.02; P = .035), -0.08 (-12 to 0.29; P = .43) and 0.01 (-0.21 to 0.19; P = .913) in placebo, atrasentan 0.75 and 1.25 mg/d, respectively. The metabolite index difference compared to placebo was 0.13 (-0.17 to 0.43; P = .40) and 0.35 (0.05-0.65; P = .02) for atrasentan 0.75 and 1.25 mg/d, respectively. These data corroborate previous findings of mitochondrial dysfunction in patients with type 2 diabetes, nephropathy and eGFR < 60 mL/min/1.73 m2 , suggesting that atrasentan may prevent the progression of mitochondrial dysfunction common to this specific patient population. Future studies of longer treatment duration with atrasentan are indicated.
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Affiliation(s)
- Michelle J Pena
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Dick de Zeeuw
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Dennis Andress
- Renal Clinical Development, AbbVie, North Chicago, Illinois
| | - John J Brennan
- Renal Clinical Development, AbbVie, North Chicago, Illinois
| | - Ricardo Correa-Rotter
- Department of Nephrology and Mineral Metabolism, National Medical Science and Nutrition Institute Salvador Zubirán, Mexico City, Mexico
| | - Blai Coll
- Clinical Research Cardiovascular, Amgen Inc., Thousand Oaks, California
| | - Donald E Kohan
- Division of Nephrology, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Hirofumi Makino
- Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Vlado Perkovic
- George Institute for Global Health, University of Sydney, Sydney, Australia
| | - Giuseppe Remuzzi
- Unit of Nephrology and Dialysis, Azienda Ospedaliera Papa Giovanni XXIII, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy
- Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy
| | - Sheldon W Tobe
- Department of Hypertension and Nephrology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada
| | - Robert Toto
- Department of Clinical Science, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Hans-Henrik Parving
- Department of Medical Endocrinology, Rigshospitalet University Hospital of Copenhagen, Copenhagen, Denmark
| | | | | | - Kumar Sharma
- Institute of Metabolomic Medicine, Center for Renal Translational Medicine, Division of Nephrology-Hypertension, Division of Medical Genetics, Department of Medicine, University of California San Diego, San Diego, California
| | - Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Heerspink HJL, Makino H, Andress D, Brennan JJ, Correa-Rotter R, Coll B, Davis JW, Idler K, Kohan DE, Liu M, Perkovic V, Remuzzi G, Tobe SW, Toto R, Parving HH, de Zeeuw D. Comparison of exposure response relationship of atrasentan between North American and Asian populations. Diabetes Obes Metab 2017; 19:545-552. [PMID: 27981738 DOI: 10.1111/dom.12851] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 12/06/2016] [Accepted: 12/08/2016] [Indexed: 12/25/2022]
Abstract
AIMS The selective endothelin (ET) A receptor antagonist atrasentan has been shown to lower albuminuria in North American and Asian patients with type 2 diabetes and nephropathy. As drug responses to many drugs may differ between North American and Asian populations, we assessed the influence of geographical region on the albuminuria and fluid retention response to atrasentan. MATERIALS AND METHODS Two 12-week double-blind randomised controlled trials were performed with atrasentan 0.75 or 1.25 mg/d vs placebo in patients with type 2 diabetes and nephropathy. The efficacy endpoint was the percentage change in albuminuria. Bodyweight change, a proxy of fluid retention, was used as a safety endpoint. Pharmacodynamics were determined in Asians (N = 77) and North Americans (N = 134). Atrasentan plasma concentration was measured in 161 atrasentan-treated patients. RESULTS Mean albuminuria reduction in Asian, compared to North American, patients was, respectively, -34.4% vs -26.3% for 0.75 mg/d ( P = .44) and -48.0% vs -28.9% for 1.25 mg/d ( P = .035). Bodyweight gain did not differ between North American and Asian populations. Atrasentan plasma concentrations were higher in Asians compared to North Americans and correlated with albuminuria response (7.2% albuminuria reduction per doubling atrasentan concentration; P = .024). Body surface area (β = -1.09 per m2 ; P < .001) and bilirubin, as a marker of hepatic organic anion transporter activity, (β = 0.69 per mg/dL increment; P = .010) were independent determinants of atrasentan plasma concentration; correction by body surface area and bilirubin left no significant difference in plasma concentration between Asian and North American populations. CONCLUSION The higher exposure and albuminuria reduction of atrasentan in Asian patients is not associated with more fluid retention, suggesting that Asian patients are less sensitive to atrasentan-induced sodium retention.
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Affiliation(s)
- Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Hirofumi Makino
- Okayama University Graduate School of Medicine, Okayama City, Okayama, Japan
| | | | | | - Ricardo Correa-Rotter
- Department of Nephrology and Mineral Metabolism, National Medical Science and Nutrition Institute Salvador Zubirán, Mexico City, Mexico
| | - Blai Coll
- Renal Clinical Development, AbbVie, Chicago, Illinois
| | | | - Ken Idler
- Renal Clinical Development, AbbVie, Chicago, Illinois
| | - Donald E Kohan
- Division of Nephrology, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Mohan Liu
- Renal Clinical Development, AbbVie, Chicago, Illinois
| | - Vlado Perkovic
- George Institute for Global Health, University of Sydney, Sydney, Australia
| | - Giuseppe Remuzzi
- Azienda Ospedaliera Papa Giovanni XXIII and IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy
| | - Sheldon W Tobe
- Department of Hypertension and Nephrology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - Robert Toto
- Department of Clinical Science, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Hans-Henrik Parving
- Department of Medical Endocrinology, Rigshospitalet University Hospital of Copenhagen, Copenhagen, Denmark
| | - Dick de Zeeuw
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Abstract
Chronic kidney disease (CKD) is a lethal and rapidly increasing burden on society. Despite this, there are relatively few therapies in development for the treatment of CKD. Several recent costly phase 3 trials have failed to provide improved renal outcomes, diminishing interest in pharmaceutical investment. Furthermore, poor patient, physician, and payer awareness of CKD as a diagnosis has contributed to slow trial enrollment and successful implementation of these trials. Nevertheless, several therapeutics remain in development for the treatment of CKD, including mineralocorticoid-receptor antagonists, sodium/glucose cotransporter 2 inhibitors, anti-inflammatory drugs, and drugs that mitigate oxidative injury. Success of future CKD therapeutic trials will depend not only on improved understanding of disease pathogenesis, but also on improved trial enrollment rates, through increasing awareness of this disease by the public, policy makers, and the greater medical community.
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Affiliation(s)
- Matthew D Breyer
- Biotechnology Discovery Research, Eli Lilly and Company, Indianapolis, IN.
| | - Katalin Susztak
- Renal Electrolyte and Hypertension Division, Department of Medicine, University of Pennsylvania, Philadelphia, PA
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Boels MGS, Avramut MC, Koudijs A, Dane MJC, Lee DH, van der Vlag J, Koster AJ, van Zonneveld AJ, van Faassen E, Gröne HJ, van den Berg BM, Rabelink TJ. Atrasentan Reduces Albuminuria by Restoring the Glomerular Endothelial Glycocalyx Barrier in Diabetic Nephropathy. Diabetes 2016; 65:2429-39. [PMID: 27207530 DOI: 10.2337/db15-1413] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 03/20/2016] [Indexed: 12/17/2022]
Abstract
Atrasentan, a selective endothelin A receptor antagonist, has been shown to reduce albuminuria in type 2 diabetes. We previously showed that the structural integrity of a glomerular endothelial glycocalyx is required to prevent albuminuria. Therefore we tested the potential of atrasentan to stabilize the endothelial glycocalyx in diabetic apolipoprotein E (apoE)-deficient mice in relation to its antialbuminuric effects. Treatment with atrasentan (7.5 mg/kg/day) for 4 weeks reduced urinary albumin-to-creatinine ratios by 26.0 ± 6.5% (P < 0.01) in apoE knockout (KO) mice with streptozotocin-induced diabetes consuming an atherogenic diet, without changes in gross glomerular morphology, systemic blood pressure, and blood glucose concentration. Endothelial cationic ferritin surface coverage, investigated using large-scale digital transmission electron microscopy, revealed that atrasentan treatment increases glycocalyx coverage in diabetic apoE KO mice from 40.7 ± 3.2% to 81.0 ± 12.5% (P < 0.05). This restoration is accompanied by increased renal nitric oxide concentrations, reduced expression of glomerular heparanase, and a marked shift in the balance of M1 and M2 glomerular macrophages. In vitro experiments with endothelial cells exposed to laminar flow and cocultured with pericytes confirmed that atrasentan reduced endothelial heparanase expression and increased glycocalyx thickness in the presence of a diabetic milieu. Together these data point toward a role for the restoration of endothelial function and tissue homeostasis through the antialbuminuric effects of atrasentan, and they provide a mechanistic explanation for the clinical observations of reduced albuminuria with atrasentan in diabetic nephropathy.
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Affiliation(s)
- Margien G S Boels
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - M Cristina Avramut
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Angela Koudijs
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Martijn J C Dane
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Dae Hyun Lee
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Johan van der Vlag
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Abraham J Koster
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Anton Jan van Zonneveld
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Ernst van Faassen
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Hermann-Josef Gröne
- Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany
| | - Bernard M van den Berg
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Ton J Rabelink
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
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Qi P, Chen M, Zhang LX, Song RX, He ZH, Wang ZP. A Meta-Analysis and Indirect Comparison of Endothelin A Receptor Antagonist for Castration-Resistant Prostate Cancer. PLoS One 2015; 10:e0133803. [PMID: 26192308 PMCID: PMC4508042 DOI: 10.1371/journal.pone.0133803] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 06/30/2015] [Indexed: 01/08/2023] Open
Abstract
Background Endothelin A (ET-A) receptor antagonists including zibotentan and atrasentan, have been suggested as a treatment for castration-resistant prostate cancer (CRPC). Our aim was to conduct a meta-analysis and indirect comparison to assess the efficacy and safety of ET-A receptor antagonists for treatment of CRPC. Methods We systematically searched PubMed, EMBASE, the Cochrane Library, and Web of Science from inception to November 2014 to identify randomized controlled trials (RCTs) which assessed ET-A receptor antagonists for treatment of CRPC. Meta-analysis was conducted by STATA version 12.0 software. Results Eight RCTs were identified, involving 6,065 patients. The results of direct comparison showed that compared with placebo, there was no statistically significant difference in the improvement of progression-free survival (PFS), overall survival (OS), time to disease progression (TTP), and total adverse events (AEs) with ET-A receptor antagonist treatment for CRPC. The results of ET-A receptor antagonists plus docetaxel versus docetaxel alone were similar. The indirect comparisons showed that there were no significant differences between zibotentan plus docetaxel versus atrasentan plus docetaxel when compared with docetaxel alone or zibotentan versus atrasenta compared with placebo in the improvement of PFS, OS, TTP, and total adverse events. Conclusions There were no significant benefits for ET-A receptor antagonists with or without docetaxel in the improvement of PFS, OS, TTP, and overall AEs. And there were no significant differences between zibotentan and atrasentan. Single-agent docetaxel should remain as one of the standard treatments.
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Affiliation(s)
- Ping Qi
- Institute of Urology, The Second Hospital of Lanzhou University, Lanzhou 730030, China
- Department of Clinical Laboratory, The Second Hospital of Lanzhou University, Lanzhou 730030, China
| | - Ming Chen
- Department of Urology, GanSu Provincial Hospital of Traditional Chinese Medicine, Lanzhou 730050, China
| | - Li-xiu Zhang
- Institute of Urology, The Second Hospital of Lanzhou University, Lanzhou 730030, China
| | - Rui-xia Song
- Institute of Urology, The Second Hospital of Lanzhou University, Lanzhou 730030, China
- Key Laboratory of Urological Diseases in Gansu Province, Lanzhou 730030, China
| | - Zhen-hua He
- Institute of Urology, The Second Hospital of Lanzhou University, Lanzhou 730030, China
- Department of Neurosurgery, The Second Hospital of Lanzhou University, Lanzhou 730030, China
| | - Zhi-ping Wang
- Institute of Urology, The Second Hospital of Lanzhou University, Lanzhou 730030, China
- Key Laboratory of Urological Diseases in Gansu Province, Lanzhou 730030, China
- * E-mail:
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14
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Samad MA, Kim UK, Kang JJ, Ke Q, Kang PM. Endothelin A receptor antagonist, atrasentan, attenuates renal and cardiac dysfunction in Dahl salt-hypertensive rats in a blood pressure independent manner. PLoS One 2015; 10:e0121664. [PMID: 25775254 PMCID: PMC4361570 DOI: 10.1371/journal.pone.0121664] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 02/02/2015] [Indexed: 02/02/2023] Open
Abstract
Proteinuria is a hallmark of chronic kidney disease (CKD) and cardiovascular disease (CVD), and a good predictor of clinical outcome. Selective endothelin A (ETA) receptor antagonist used with renin-angiotensin system (RAS) inhibitors prevents development of proteinuria in CKD. However, whether the improvement in proteinuria would have beneficial effects on CVD, independent of RAS inhibition, is not well understood. In this study, we investigated whether atrasentan, an ETA receptor antagonist, has renal and cardiovascular effects independent of RAS inhibition. Male Dahl salt sensitive (DSS) rats, at six weeks of age, received water with or without different doses of atrasentan and/or enalapril under high salt (HS) diet or normal diet (ND) for 6 weeks. At the end of 12th week, atrasentan at a moderate dose significantly attenuated proteinuria and serum creatinine without reducing mean arterial pressure (MAP), thereby preventing cardiac hypertrophy and improving cardiac function. ACE inhibitor enalapril at a dose that did not significantly lowered BP, attenuated cardiac hypertrophy while moderately improving cardiac function without reducing proteinuria and serum creatinine level. Nonetheless, combined therapy of atrasentan and enalapril that does not altering BP exerted additional cardioprotective effect. Based on these findings, we conclude that BP independent monotherapy of ETA receptor antagonist attenuates the progression of CKD and significantly mitigates CVD independent of RAS inhibition.
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Affiliation(s)
- Mohammed A. Samad
- Cardiovascular Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of BIN Fusion Technology, Chonbuk National University, Jeonju, South Korea
| | - Ui Kyoung Kim
- Cardiovascular Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Joshua J. Kang
- Cardiovascular Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Qingen Ke
- Cardiovascular Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Peter M. Kang
- Cardiovascular Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of BIN Fusion Technology, Chonbuk National University, Jeonju, South Korea
- * E-mail:
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15
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Kröpelin TF, de Zeeuw D, Andress DL, Bijlsma MJ, Persson F, Parving HH, Heerspink HJL. Number and frequency of albuminuria measurements in clinical trials in diabetic nephropathy. Clin J Am Soc Nephrol 2015; 10:410-6. [PMID: 25568217 PMCID: PMC4348688 DOI: 10.2215/cjn.07780814] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 11/26/2014] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Albuminuria change is often used to assess drug efficacy in intervention trials in nephrology. The change is often calculated using a variable number of urine samples collected at baseline and end of treatment. Yet more albuminuria measurements usually occur. Because albuminuria shows a large day-to-day variability, this study assessed to what extent the average and the precision of the antialbuminuric drug effect varies with the number of urine collections at each visit and the number of follow-up visits. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This study used data from three randomized intervention trials (Aliskiren Combined with Losartan in Type 2 Diabetes and Nephropathy, Selective Vitamin D Receptor Activation for Albuminuria Lowering, and Residual Albuminuria Lowering with Endothelin Antagonist Atrasentan) including patients with type 2 diabetes and macroalbuminuria. Albuminuria-lowering drug effects were estimated from one, two, or three urine collections at consecutive days before each study visit and reported as albuminuria change from baseline to end of treatment or the change over time considering an average of all follow-up albuminuria measurements. RESULTS Increasing the number of urine collections for an albuminuria measurement at baseline and end of treatment or using all study visits during follow-up did not alter the average drug effect. The precision of the drug effect increased (decreased SEM) when the number of study visits and the number of urine collections per visit were increased. Using all albuminuria measurements at all study visits led to a 4- to 6-fold reduction in sample size to detect a 30% albuminuria-lowering treatment effect with 80% power compared with using baseline and end-of-treatment albuminuria measurements alone. CONCLUSIONS Increasing the number of urine collections per study visit and the number of visits over time does not change the average drug effect estimate but markedly increases the precision, thereby enhancing statistical power. Thus, clinical trial designs in diabetic nephropathy using albuminuria as an end point can be significantly improved, leading to smaller sample sizes and less complex trials.
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Affiliation(s)
- Tobias F Kröpelin
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands
| | - Dick de Zeeuw
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands
| | | | - Maarten J Bijlsma
- Pharmacoepidemiology and Pharmacoeconomics Unit, Department of Pharmacy, University of Groningen, Groningen, The Netherlands
| | | | - Hans-Henrik Parving
- Department of Medical Endocrinology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health Science, Aarhus University, Aarhus, Denmark
| | - Hiddo J Lambers Heerspink
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands;
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16
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Nasser SA, Elmallah AI, Sabra R, Khedr MM, El-Din MMM, El-Mas MM. Blockade of endothelin ET(A), but not thromboxane, receptors offsets the cyclosporine-evoked hypertension and interrelated baroreflex and vascular dysfunctions. Eur J Pharmacol 2014; 727:52-9. [PMID: 24486390 DOI: 10.1016/j.ejphar.2014.01.034] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 01/16/2014] [Accepted: 01/22/2014] [Indexed: 01/21/2023]
Abstract
The impairment of arterial baroreceptor and vasodilator functions are two major contributors to the hypertensive action of cyclosporine (CSA). In this study, in vivo and in vitro pharmacological studies were performed to investigate whether these effects of CSA are differentially modulated by endothelin and thromboxane signaling. The treatment of rats with CSA (25mg/kg/day i.p.) for 7 consecutive days caused significant increases in blood pressure (BP), attenuated reflex heart rate (HR) responses to vasopressor (phenylephrine, PE) and vasodepressor (sodium nitroprusside, SNP) agents, and reduced cumulative vasorelaxant responses elicited by acetylcholine (Ach, 1×10(-9)-1×10(-5)M) in PE-precontracted isolated aortas. These effects of CSA were blunted after concurrent i.p. administration of atrasentan (selective ETA blocker, 10mg/kg/day), but not terutroban (thromboxane receptor blocker, 10mg/kg/day). Moreover, atrasentan reversed the reductions in aortic protein expression of eNOS caused by CSA whereas terutroban was without effect. We also report that the favorable effect of atrasentan on CSA-evoked impairment in aortic Ach responsiveness disappeared in rats treated simultaneously with L-NAME (NOS inhibitor, 10mg/kg/day) but not BQ 788 (ETB receptor blocker, 0.1mg/kg/day) or indomethacin (cycloxygenase inhibitor, 5mg/kg/day). Together, the data implicate endothelin ETA receptors in baroreflex and vascular derangements which predispose to the hypertensive effect of CSA. Moreover, the facilitation of NOS, but not ETB receptors or cycloxygenase-derived prostanoids, signaling is pivotal for advantageous effect of atrasentan on the aortic CSA-Ach interaction.
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Affiliation(s)
- Suzanne A Nasser
- Department of Pharmacology, Faculty of Pharmacy, Beirut Arab University, Lebanon
| | - Ahmed I Elmallah
- Department of Pharmacology, Faculty of Pharmacy, Alexandria University, Egypt
| | - Ramzi Sabra
- Department of Pharmacology, Faculty of Medicine, American University of Beirut, Lebanon
| | - Mohamed M Khedr
- Department of Pharmacology, Faculty of Medicine, Alexandria University, Egypt
| | | | - Mahmoud M El-Mas
- Department of Pharmacology, Faculty of Pharmacy, Alexandria University, Egypt.
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17
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Tan RJ, Zhou L, Zhou D, Lin L, Liu Y. Endothelin receptor a blockade is an ineffective treatment for adriamycin nephropathy. PLoS One 2013; 8:e79963. [PMID: 24265790 PMCID: PMC3825716 DOI: 10.1371/journal.pone.0079963] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 09/28/2013] [Indexed: 11/24/2022] Open
Abstract
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.
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Affiliation(s)
- Roderick J. Tan
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Lili Zhou
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Dong Zhou
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Lin Lin
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Youhua Liu
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- * E-mail:
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18
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Saleh MA, Boesen EI, Pollock JS, Savin VJ, Pollock DM. Endothelin receptor A-specific stimulation of glomerular inflammation and injury in a streptozotocin-induced rat model of diabetes. Diabetologia 2011; 54:979-88. [PMID: 21191784 PMCID: PMC3804244 DOI: 10.1007/s00125-010-2021-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Accepted: 11/29/2010] [Indexed: 10/18/2022]
Abstract
AIMS/HYPOTHESIS Activation of endothelin receptor-A (ET(A)) increases glomerular permeability to albumin (P(alb)) and elevates pro-inflammatory markers in hyperglycaemic rats. METHODS Male Sprague-Dawley rats were given streptozotocin (n = 32) or saline (sham; n = 32). Half of the animals in each group received the ET(A)-selective antagonist, ABT-627 (atrasentan; orally), beginning immediately after hyperglycaemia was confirmed. Glomeruli were isolated by sieving techniques and P(alb) determined from the change in glomerular volume induced by oncotic gradients of albumin. Glomerular nephrin levels were assessed by immunofluorescence, whereas urinary nephrin was measured by immunoassay. RESULTS At 3 and 6 weeks after streptozotocin injection, proteinuria was significantly increased compared with sham controls and significantly reduced by ABT-627 treatment. P(alb) was also increased at 3 and 6 weeks post-streptozotocin. ABT-627 had no effect on P(alb) or protein excretion in sham control rats. In glomeruli isolated from hyperglycaemic rats, incubation with BQ-123, a selective ET(A) antagonist, reduced P(alb), whereas BQ-788, a selective endothelin receptor-B antagonist had no effect (n = 6 rats per group, 5-8 glomeruli per rat). Glomerular and plasma content of soluble intercellular adhesion molecule-1 and monocyte chemoattractant protein-1 were significantly increased 6 weeks after streptozotocin (ELISA). ABT-627 attenuated these increases. After 6 weeks of hyperglycaemia, glomerular nephrin content was decreased with a concurrent increase in urinary nephrin excretion. ABT-627 prevented glomerular nephrin loss in hyperglycaemic rats (n = 5-8 rats per group; eight groups). CONCLUSIONS/INTERPRETATION These observations support the hypothesis that endothelin-1, via the ET(A) receptor, directly increases P(alb), possibly via nephrin loss, as well as early inflammation in the hyperglycaemic rat.
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Affiliation(s)
- M A Saleh
- Vascular Biology Center, Medical College of Georgia, 1459 Laney Walker Blvd, Augusta, GA 30907-2500, USA
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19
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Mansart A, Ruff LJ, Ariaans MP, Ross JJ, Reilly CS, Brown NJ, Kaufman S, Brookes ZLS. Constriction of rat extra-splenic veins to lipopolysaccharide involves endothelin-1. Naunyn Schmiedebergs Arch Pharmacol 2010; 381:555-62. [PMID: 20397012 DOI: 10.1007/s00210-010-0514-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 03/11/2010] [Indexed: 11/30/2022]
Abstract
The spleen has an important role in blood volume regulation and increased resistance of post-capillary hilar veins (in mesentery adjoining the spleen) can regulate this. This study investigated whether venular constriction to lipopolysaccharide (LPS) involved endothelin-1 (ET-1). Pressure myography was used to study isolated extra-splenic (hilar) vessels from male Wistar rats (n = 111). Arteries and veins were treated with LPS (50 microg ml(-1)) for 4 h. Extra-splenic veins constricted to LPS (p < 0.05), but there was no effect on arteries. Denudation did not abolish venular constriction to LPS, indicating an endothelial independent mechanism. However, the dual ET-1 receptor antagonist bosentan (10(-5) M) and specific ET(A) and ET(B) antagonists ABT-627 (atrasentan, 6.3 x 10(-6) M) and A-192621(1.45 x 10(-6) M) completely abolished constriction of LPS-treated veins. ET-1 alone also constricted the extra-splenic arteries and veins (p < 0.05), with a greater response observed in veins (p < 0.05). ELISA also confirmed that serum and spleen levels of ET-1 increased in response to LPS (p < 0.05). That LPS-induced constriction of extra-splenic veins is mediated by ET-1. Greater constriction of post- versus pre-capillary extra-splenic vessels to LPS would result in increased intra-splenic fluid extravasation and hypovolaemia in vivo.
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Affiliation(s)
- Arnaud Mansart
- Academic Unit of Anaesthesia, University of Sheffield, Royal Hallamshire Hospital, Sheffield, S10 2RX, UK
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20
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Abstract
Advanced prostate cancer frequently metastasizes to bone and remains an incurable disease. One recent experimental therapy involves endothelin receptor A (ETA) antagonists (e.g., atrasentan). Clinical results to date have been mixed, with atrasentan not meeting its primary endpoints in a Phase III trial. It remains an open question whether some patients might benefit from this therapy, while others may not. Preclinical data supports the concept that the endothelin signaling axis may be particularly important for tumor growth in bone, but the extent to which it is involved in metastatic colonization of other organ sites in prostate cancer remains unclear. Here we evaluate the efficacy of atrasentan in a mouse model of prostate cancer metastatic colonization. Using bioluminescence imaging, we show that atrasentan does inhibit tumor growth in, but not the initial colonization of, bony sites in intracardially-injected 22Rv1 prostate cancer cells. However, atrasentan shows little efficacy in soft tissues such as adrenal gland or liver. Our studies show that whether atrasentan exhibits significant overall antitumor efficacy and survival benefit depends on the presence of bone metastasis evident in that animal. Though in contrast to previous findings efficacy is apparent in a prostate tumor model that elicits mixed osteoblastic/osteolytic lesions. These data confirm the notion that atrasentan may exhibit selective activity against prostate cancer bone metastasis, mirroring clinical findings, and suggest that the role of endothelin signaling in bone metastasis may be more complex than previously appreciated. The model described here may provide a valuable tool for unraveling this complexity.
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Affiliation(s)
- Justin M Drake
- Department of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
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21
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LaMarca B, Parrish M, Ray LF, Murphy SR, Roberts L, Glover P, Wallukat G, Wenzel K, Cockrell K, Martin JN, Ryan MJ, Dechend R. Hypertension in response to autoantibodies to the angiotensin II type I receptor (AT1-AA) in pregnant rats: role of endothelin-1. Hypertension 2009; 54:905-9. [PMID: 19704104 PMCID: PMC2785498 DOI: 10.1161/hypertensionaha.109.137935] [Citation(s) in RCA: 158] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Agonistic autoantibodies to the angiotensin II type I receptor (AT1-AA) and endothelin -1 (ET-1) are suggested to be important links between placental ischemia and hypertension during preeclampsia. Activation of the angiotensin II type 1 receptor (AT1R) increases endothelial cell production of ET-1; however, the importance of ET-1 in response to AT1-AA-mediated AT1 R activation during preeclampsia is unknown. Furthermore, the role of AT1-AA-mediated increases in blood pressure during pregnancy remains unclear. The objective of this study was to test the hypothesis that AT1-AA, increased to levels observed in preeclamptic women and placental ischemic rats, increases mean arterial pressure (MAP) by activation of the ET-1 system. Chronic infusion of purified rat AT1-AA into normal pregnant (NP) rats for 7 days increased AT1-AA from 0.68+/-0.5 to 10.88+/-1.1 chronotropic units (P<0.001). The increased AT1-AA increased MAP from 99+/-1 to 119+/-2 mm Hg (P<0.001). The hypertension was associated with significant increases in renal cortices (11-fold) and placental (4-fold) ET-1. To determine whether ET-1 mediates AT1-AA-induced hypertension, pregnant rats infused with AT1-AA and NP rats were treated with an ET(A) receptor antagonist. MAP was 100+/-1 mm Hg in AT1-AA+ET(A) antagonist-treated rats versus 98+/-2 mm Hg in ET(A) antagonist-treated rats. Collectively, these data support the hypothesis that one potential pathway whereby AT1-AAs increase blood pressure during pregnancy is by an ET-1-dependent mechanism.
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Affiliation(s)
- Babbette LaMarca
- Department of Obstetrics & Gynecology, Division of Maternal-Fetal Medicine, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216-4505, USA.
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Chichorro JG, Zampronio AR, Cabrini DA, Franco CRC, Rae GA. Mechanisms operated by endothelin ETA and ETB receptors in the trigeminal ganglion contribute to orofacial thermal hyperalgesia induced by infraorbital nerve constriction in rats. Neuropeptides 2009; 43:133-42. [PMID: 19157542 DOI: 10.1016/j.npep.2008.12.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 12/02/2008] [Accepted: 12/03/2008] [Indexed: 11/26/2022]
Abstract
Endothelins, acting through specific endothelin ET(A) and/or ET(B) receptors, participate in nociceptive processing in models of cancer, inflammatory and neuropathic pain. The present study investigated which cell types express endothelin receptors in the trigeminal ganglion, and the contribution of mechanisms mediated by endothelin ET(A) and ET(B) receptors to orofacial heat hyperalgesia induced by unilateral constriction of the infraorbital nerve (CION). Both receptor types were identified by immunohistochemistry in the trigeminal ganglion, ET(A) receptors on small-sized non-myelinated and myelinated A-fibers and ET(B) receptors on both satellite glial cells and small-sized non-myelinated neuronal cells. CION promoted ipsilateral orofacial heat hyperalgesia which lasted from Day 2 until Day 10 after surgery. Ongoing CION-induced heat hyperalgesia (on Day 4) was reduced transiently, but significantly, by systemic or local treatment with antagonists of endothelin ET(A) receptors (atrasentan, 10 mg/kg, i.v.; or BQ-123, 10 nmol/lip), endothelin ET(B) receptors (A-192621, 20 mg/kg, i.v.; or BQ-788, 10 nmol/ lip), or of both ET(A)/ET(B) receptors (bosentan, 10 mg/kg, i.v.; or BQ-123 plus BQ-788, each at 10 nmol/lip). On the other hand, CION-induced heat hyperalgesia was transiently abolished over the first 90 min following i.p. injection of morphine hydrochloride (2.5 mg/kg), but fully resistant to reversal by indomethacin (4 mg/kg, i.p.) or celecoxib (10 mg/kg, i.p.). Thus, heat hyperalgesia induced by CION is maintained, in part, by peripheral signaling mechanisms operated by ET(A) and ET(B) receptors. Endothelin receptors might represent promising therapeutic targets for the control of trigeminal neuropathic pain.
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Affiliation(s)
- Juliana G Chichorro
- Department of Pharmacology, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianopolis, SC, Brazil
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23
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Abstract
Renal medullary endothelin B receptors contribute to blood pressure regulation by facilitating salt excretion. Premenopausal females have relatively less hypertension than males; therefore, we examined whether there is a sex difference in the natriuretic response to renal medullary infusion of endothelin peptides in the rat. All of the experiments were conducted in anesthetized wild-type (wt) or endothelin B-deficient (sl/sl) rats. Infusion of endothelin 1 (ET-1) significantly increased sodium excretion (U(Na)V) in female, but not male, wt rats (Delta U(Na)V: 0.41+/-0.07 versus -0.04+/-0.06 micromol/min, respectively). The endothelin B receptor agonist sarafotoxin 6c produced similar increases in U(Na)V in both male (Delta 0.58+/-0.15 micromol/min) and female (Delta 0.67+/-0.18 micromol/min) wt rats. Surprisingly, ET-1 markedly increased U(Na)V in female (Delta 0.70+/-0.11 micromol/min) but not male sl/sl rats (Delta 0.00+/-0.05 micromol/min). ET-1 had no effect on medullary blood flow in females, although medullary blood flow was significantly reduced to a similar extent in males of both strains. These results suggest that the lack of a natriuretic response to ET-1 in male rats is because of reductions in medullary blood flow. Treatment with ABT-627, an endothelin A receptor antagonist, or N(G)-propyl-L-arginine, an NO synthase 1 inhibitor, prevented the increase in U(Na)V observed in female rats. Gonadectomy eliminated the sex difference in the U(Na)V and medullary blood flow response to ET-1. These findings demonstrate that there is no sex difference in endothelin B-dependent natriuresis, and the endothelin A receptor contributes to ET-1-dependent natriuresis in female rats, an effect that requires NO synthase 1. These findings provide a possible mechanism for why premenopausal women are more resistant to salt-dependent hypertension.
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Affiliation(s)
- Daisuke Nakano
- Vascular Biology Center, Medical College of Georgia, 1459 Laney Walker Blvd, Augusta, GA 30912, USA
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25
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Rosanò L, Spinella F, Di Castro V, Natali PG, Bagnato A. Therapeutic targeting of the endothelin-A receptor in human ovarian carcinoma: efficacy of cytotoxic agents is markedly enhanced by co-administration with atrasentan. J Cardiovasc Pharmacol 2008; 44 Suppl 1:S132-5. [PMID: 15838262 DOI: 10.1097/01.fjc.0000166259.96980.6a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The endothelin-1/endothelin-A receptor autocrine pathway is overexpressed in ovarian carcinoma. We explored the efficacy of atrasentan (ABT-627), a small orally active endothelin- A receptor antagonist, in monotherapy and combination therapy on HEY ovarian carcinoma xenografts. Atrasentan (2 mg/kg per 24 hours i.p. for 21 days) induced similar inhibition of tumor growth as paclitaxel (20 mg/kg i.v. three times a day every 4 days) with a reduction of 65% compared to control. The co-administration of atrasentan enhanced the efficacy of cytotoxic agents, such as taxanes or platinum compounds. Administration of atrasentan in combination with paclitaxel caused a strong antitumor effect. Remarkably, four of ten mice bearing HEY xenografts had no histological evidence of tumors. Tumor growth inhibition was accompanied by a significant decrease of molecular effectors involved in angiogenesis and invasion and by enhanced tumor cell apoptosis. Moreover, although cisplatinum as a single agent (5 mg/kg i.p. on day 1) markedly inhibited HEY tumors, atrasentan was very effective in potentiating this effect, with partial or complete tumor regression. The antitumor, anti-angiogenic, and apoptotic activities obtained with atrasentan and the enhanced efficacy of cytotoxic agents provide a rationale for its clinical evaluation in ovarian carcinoma.
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Affiliation(s)
- Laura Rosanò
- Laboratory of Molecular Pathology and Ultrastructure, Regina Elena Cancer Institute, Rome, Italy
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26
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Yamamoto S, Matsumoto N, Kanazawa M, Fujita M, Takaoka M, Matsumura Y. Effects of ET(A) and ET(B) receptor blockade on post-ischemic cardiac dysfunction and norepinephrine overflow in isolated rat hearts. J Cardiovasc Pharmacol 2008; 44 Suppl 1:S394-7. [PMID: 15838330 DOI: 10.1097/01.fjc.0000166297.02819.f2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We investigated the role of endothelin-A (ETA) and endothelin-B (ETB) receptors in ischemia/reperfusion-induced cardiac dysfunction and norepinephrine overflow using isolated rat hearts. According to the Langendorff technique, isolated hearts were subjected to 40 minutes of global ischemia followed by 30 minutes of reperfusion. Ischemia/reperfusion led to decreases in left ventricular developed pressure and coronary flow, and an increase in left ventricular end-diastolic pressure compared with pre-ischemic basal levels. An ETB receptor antagonist A-192621 at 1 microM worsened ischemia/reperfusion-induced cardiac dysfunction. In contrast, an ETA receptor antagonist ABT-627 at 5 microM with or without A-192621 improved the aforementioned cardiac dysfunction, to the same extent. Norepinephrine was massively released in coronary effluent from the hearts exposed to ischemia/ reperfusion. Treatment with ABT-627 significantly suppressed the norepinephrine overflow induced by the ischemia/reperfusion whereas A-192621 further enhanced it, which was completely abolished by the concomitant treatment with ABT-627. These results suggest that the detrimental effect of ETB receptor blockade on post-ischemic cardiac function is mediated by the ETA receptor-related action and that norepinephrine overflow from sympathetic nerve endings is closely related to the antagonist-induced functional changes of post-ischemic hearts.
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Affiliation(s)
- Satoshi Yamamoto
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki, Osaka, Japan
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27
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Elmarakby AA, Dabbs Loomis E, Pollock JS, Pollock DM. ETA receptor blockade attenuates hypertension and decreases reactive oxygen species in ETB receptor-deficient rats. J Cardiovasc Pharmacol 2008; 44 Suppl 1:S7-10. [PMID: 15838363 DOI: 10.1097/01.fjc.0000166205.66555.40] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We hypothesize that endothelin-A receptor stimulation contributes to the elevated blood pressure and superoxide production in endothelin-B receptor-deficient rats on a high salt diet. Experiments were conducted on homozygous endothelin-B-deficient (sl/sl) and wild-type rats (wt) fed a high salt diet (8% NaCl) for 3 weeks. Separate groups were given normal drinking water or water containing the endothelin-A receptor antagonist, ABT-627 (5 mg/kg per day; n = 8-9 in all groups). On a normal salt diet, (sl/sl) rats had a significantly elevated systolic blood pressure compared with wt (138 +/- 3 vs 117 +/- 4 mmHg, respectively; P < 0.05). High salt diet caused a significant increase in systolic blood pressure in (sl/sl) rats compared with wt (158 +/- 2 vs 138 +/- 3 mmHg, respectively; P < 0.05). Endothelin-A receptor blockade decreased systolic blood pressure in (sl/sl) rats on high salt (125 +/- 5 mmHg; P < 0.05 vs without antagonist) without affecting the systolic blood pressure in wt (119 +/- 4 mmHg). Aortic superoxide production (lucigenin chemiluminescence) and plasma 8-isoprostane were elevated in sl/sl rats and were significantly reduced by endothelin-A receptor blockade in sl/sl, but not in wt rats. These findings suggest that endothelin-1, through the endothelin-A receptor, contributes to salt-induced hypertension and vascular superoxide production in endothelin-B-deficient rats.
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Affiliation(s)
- Ahmed A Elmarakby
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta 30912-2500, USA
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Patel TA, Belcher E, Warner TD, Harding SE, Mitchell JA. Identification and characterization of a dysfunctional cardiac myocyte phenotype: role of bacteria, Toll-like receptors, and endothelin. Shock 2008; 28:434-40. [PMID: 17558348 DOI: 10.1097/shk.0b013e31804a55a7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cardiac myocyte dysfunction is clearly identified as underlying the acute heart failure associated with bacterial infection, as well as the chronic syndrome following cardiac damage, but the mechanisms leading to dysfunction in each case are not fully established. It is thought that local hormones such as endothelin 1 (ET-1) can increase the risk of heart failure in acute or chronic conditions. In the current study, we characterize myocytes as populations and identify a novel phenotype of the ventricular cardiac myocyte that does not contract appropriately on electrical stimulation. The noncontractile cardiac myocytes were viable and had normal calcium transients. The proportion of noncontractile cardiac myocytes was increased by bacteria (gram-positive Staphylococcus aureus or gram-negative Escherichia coli). Using selective ligands or myocytes from genetically modified mice, we established that the effects of S. aureus were mediated by Toll-like receptor 2/6 and of E. coli by Toll-like receptor 4. The transition to the noncontractile phenotype was strongly inhibited by ETA antagonism but unaffected by inhibition of NOS, suggesting that ET-1 and not NO mediates this phenomenon. These results are the first to describe the characteristics of this noncontractile phenotype and the mechanisms of its induction by bacteria. Description of the myocyte population, instead of effects only on individual cells, will be more relevant to the prediction of the depression of cardiac function.
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Affiliation(s)
- Trupti A Patel
- Department of Cardiothoracic Pharmacology, National Heart and Lung Institute, Imperial College London, London, United Kingdom
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Carducci MA, Saad F, Abrahamsson PA, Dearnaley DP, Schulman CC, North SA, Sleep DJ, Isaacson JD, Nelson JB. A phase 3 randomized controlled trial of the efficacy and safety of atrasentan in men with metastatic hormone-refractory prostate cancer. Cancer 2007; 110:1959-66. [PMID: 17886253 DOI: 10.1002/cncr.22996] [Citation(s) in RCA: 248] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND The objective of this study was to evaluate the efficacy and safety of atrasentan (Xinlay), a selective endothelin-A receptor antagonist, in patients with metastatic hormone-refractory prostate cancer (HRPC). METHODS This multinational, double-blind, placebo-controlled trial enrolled 809 men with metastatic HRPC. Patients were randomized 1:1 to receive either atrasentan 10 mg per day or placebo. The primary endpoint was time to disease progression (TTP), which was determined according to radiographic and clinical measures. Analyses of overall survival and changes in biomarkers also were performed. RESULTS Atrasentan did not reduce the risk of disease progression relative to placebo (hazards ratio, 0.89; 95% confidence interval, 0.76-1.04; P = .136). Most patients progressed radiographically at the first 12-week bone scan without concomitant clinical progression. In exploratory analyses, increases from baseline to final bone alkaline phosphatase (BAP) and prostate-specific antigen (PSA) levels were significantly lower with atrasentan treatment (P < .05 for each). The median time to BAP progression (>/=50% increase from nadir) was twice as long with atrasentan treatment (505 days vs 254 days; P < .01). The delay in time to PSA progression did not reach statistical significance. Atrasentan generally was tolerated well, and the most common adverse events associated with treatment were headache, rhinitis, and peripheral edema, reflecting the vasodilatory and fluid-retention properties of endothelin-A receptor antagonism. CONCLUSIONS Atrasentan did not delay disease progression in men with metastatic HRPC despite evidence of biologic effects on PSA and BAP as markers of disease burden.
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Affiliation(s)
- Michael A Carducci
- Prostate Cancer Program, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland, USA.
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30
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Abstract
OBJECTIVE Review the recent advances in the treatment of androgen independent prostate cancer (AIPC). METHODS Review recent abstracts and literature utilizing Medline/PubMed using key words: androgen independent/hormone refractory prostate cancer, novel treatment options, Phase II, III trials and meeting abstracts/presentations. CONCLUSION Two pivotal trials SWOG (Southwest Oncology Group) study 9916 and Taxotere 327 have shown that survival can be improved in this population by administration of chemotherapy with docetaxel every three weeks intravenously. An overall survival of 19 months could be achieved with docetaxel/prednisone compared to 16 months with mitoxantrone/prednisone. Despite this, there is a need to improve on this survival benefit because the relapse free survival among responders is often short (6 months) and patients often would have progression of their cancer leading to death. Satraplatin, a novel platinum analogue had been found to provide an additional 1.5 week progression free survival benefit in this population in the second line setting. There is however, a need to develop less toxic drugs that would improve survival significantly.
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Affiliation(s)
- W Tan
- Genitourinary Oncology, Hematology, Oncology Mayo Clinic, Jacksonville, Florida 32224, USA.
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Gorenflo M, Ullmann MV, Herpel E, Neumayer S, Dieckmann R, Demirakca S, Klimpel H, Hagl S, Gebhard MM. Atrasentan treatment of pulmonary vascular disease in piglets with increased pulmonary blood flow. J Cardiovasc Pharmacol 2007; 50:286-92. [PMID: 17878757 DOI: 10.1097/fjc.0b013e3180a02ec3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We studied the effect of chronic endothelin A receptor blockade by atrasentan on the pulmonary endothelin-1 system and vascular endothelial growth factor (VEGF) expression in piglets with high pulmonary blood flow. Twenty-five 4-week-old piglets with high pulmonary blood flow were randomized to three groups: sham operated (n = 8), placebo (water) (n = 7), or treatment with atrasentan (2 mg/kg per day) (n = 10). After 3 months, mean pulmonary arterial pressure (PAP) was higher in the placebo group than in the sham group [18 +/- 2 mm Hg versus 14 +/- 1 mm Hg; P < 0.05 (ANOVA)]. Atrasentan treatment was associated with lower cardiac output, PAP (14 +/- 1 mm Hg), and medial wall thickness of pulmonary arteries (diameter: 50-150 microM) compared with placebo [13.6 +/- 3.0% versus 18.1 +/- 4.2%; P < 0.05 (ANOVA)]. Quantitative real-time polymerase chain reaction for endothelin-1, endothelin B receptor, and endothelin-converting enzyme-1 mRNA in lung tissue did not differ. However, immunostaining as well as mRNA for VEGF were lower in atrasentan-treated animals (relative gene expression: atrasentan versus placebo: 0.8 +/- 0.3 versus 1.5 +/- 0.3; P = 0.009). Atrasentan treatment effectively reduces medial hypertrophy in piglets with chronic pulmonary hyperperfusion. Chronic endothelin A receptor blockade by atrasentan may interfere with the expression of VEGF.
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Affiliation(s)
- Matthias Gorenflo
- Department of Pediatric Cardiology, Mannheim University of Heidelberg, Heidelberg, Germany.
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32
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Sachidanandam K, Portik-Dobos V, Harris AK, Hutchinson JR, Muller E, Johnson MH, Ergul A. Evidence for vasculoprotective effects of ETB receptors in resistance artery remodeling in diabetes. Diabetes 2007; 56:2753-8. [PMID: 17670915 DOI: 10.2337/db07-0426] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Vascular remodeling, characterized by extracellular matrix deposition and increased media-to-lumen (M/l) ratio, contributes to the development of microvascular complications in diabetes. Matrix metalloproteinases (MMPs) play an important role in the regulation of extracellular matrix (ECM) turnover and vascular remodeling. Vasoactive factor endothelin (ET)-1 not only causes potent vasoconstriction but also exerts profibrotic and proliferative effects that change vessel architecture, which makes it a likely candidate for a key role in vascular complications of diabetes. Thus, this study investigated the regulation of MMP activity of resistance arteries under mild-to-moderate diabetes conditions, as seen in type 2 diabetes, and the relative role of ET receptors in this process. RESEARCH DESIGN AND METHODS Vessel structure, MMP activity, and ECM proteins were assessed in control Wistar and diabetic Goto-Kakizaki (GK) rats treated with vehicle, ET(A) receptor antagonist atrasentan (5 mg x kg(-1) x day(-1)), or ET(B) receptor antagonist A-192621 (15 mg x kg(-1) x day(-1)) for 4 weeks. RESULTS M/l ratio was increased in diabetes. Atrasentan prevented this increase, whereas A-192621 caused further thickening of the medial layer. Increased MMP-2 activity in diabetes was prevented by atrasentan treatment. Collagenase activity was significantly decreased in diabetes, and while ET(A) antagonism improved enzyme activity, ET(B) blockade further reduced collagenase levels. Accordingly, collagen deposition was augmented in GK rats, which was reversed by atrasentan but exacerbated with A-192621. CONCLUSIONS ET-1 contributes to the remodeling of mesenteric resistance arteries in diabetes via activation of ET(A) receptors, and ET(B) receptors provide vasculoprotective effects.
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Affiliation(s)
- Kamakshi Sachidanandam
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, USA
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33
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Abstract
OBJECTIVE Endothelin-1 (ET-1) may play a role in carcinogenesis. ET-1 axis is overexpressed in thyroid carcinoma. We investigated the expression and the production of ET-1 by thyroid cancer cells as well as the effect of ET-1 receptor antagonism on cell proliferation. DESIGN Human papillary and follicular thyroid carcinoma cell lines were cultured. MEASUREMENTS (i) Prepro-ET-1, ET-1 receptors (ETA R and ETB R) and ET-1 converting enzyme (ECE) by reverse transcriptase polymerase chain reaction (RT-PCR); (ii) the presence of ETA R by western blot; (iii) ET-1 concentrations in medium by an enzyme immunometric assay; (iiii) the proliferation of cells by BrdU and tritiated thymidine incorporation. RESULTS RT-PCR detected the presence of mRNA for prepro-ET-1, ETA R and ECE in papillary and follicular carcinoma cells. ETB R was only expressed by follicular cells. ETA R was also detected in both cell types by western blot. Measurements of ET-1 concentrations demonstrated a secretion of active ET-1 by the cells. ETA R antagonism with atrasentan reduced cell proliferation by 16% in papillary carcinoma cells (P < 0.05) and by 51% in follicular carcinoma cells (P < 0.001). CONCLUSIONS Papillary and follicular carcinoma cells express all components of the ET-1 axis. ETA R antagonism exerts antiproliferative effects, which opens up new therapeutic perspectives in thyroid carcinoma.
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MESH Headings
- Adenocarcinoma, Follicular/metabolism
- Adenocarcinoma, Follicular/pathology
- Aspartic Acid Endopeptidases/analysis
- Aspartic Acid Endopeptidases/genetics
- Atrasentan
- Blotting, Western
- Bromodeoxyuridine/metabolism
- Carcinoma, Papillary/metabolism
- Carcinoma, Papillary/pathology
- Cell Line, Tumor
- Cell Proliferation
- Endothelin A Receptor Antagonists
- Endothelin-1/analysis
- Endothelin-1/genetics
- Endothelin-1/physiology
- Endothelin-Converting Enzymes
- Humans
- Immunoradiometric Assay
- Metalloendopeptidases/analysis
- Metalloendopeptidases/genetics
- Pyrrolidines/pharmacology
- RNA, Messenger/analysis
- Receptor, Endothelin A/analysis
- Receptor, Endothelin A/genetics
- Receptor, Endothelin B/analysis
- Receptor, Endothelin B/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Thymidine/metabolism
- Thyroid Neoplasms/metabolism
- Thyroid Neoplasms/pathology
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Affiliation(s)
- Julian E Donckier
- Molecular Physiology Research Unit, Laboratory of Physiology and Pharmacology, FUNDP, University of Namur, Namur, Belgium.
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34
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Gordi T. Comments on "Dual effects of rifampin on the pharmacokinetics of atrasentan". J Clin Pharmacol 2007; 47:1181; author reply 1182. [PMID: 17766702 DOI: 10.1177/0091270007305300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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35
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Abstract
Endothelin (ET) exerts powerful pressor actions primarily through activation of the ET(A) receptor subtype. The ET(B) receptor (ET(B)R) subtype, on the other hand, is generally thought to initiate physiological actions that decrease arterial pressure. Such actions include clearing ET from the bloodstream, initiating endothelium-mediated vasodilation, and facilitating renal sodium and water excretion. The effect of long-term activation of the ET(B)R on arterial pressure, however, never has been directly tested. In this study we evaluated cardiovascular responses to chronic (5-day) activation of ET(B)R in male rats using continuous intravenous infusion of the selective agonist sarafotoxin 6c. Surprisingly, we found that sarafotoxin 6c caused a sustained increase in arterial pressure that rapidly reversed on termination of infusion. The hypertension was associated with increased renal excretion of sodium and water and decreased plasma volume. Alterations in daily sodium intake did not affect the magnitude of the hypertension. Hemodynamic studies revealed a decreased cardiac output and increased total peripheral resistance during sarafotoxin 6c infusion. Infusion of sarafotoxin 6c caused a small increase in plasma ET levels. Nevertheless, the hypertension was not affected by coadministration of a selective ET(A) receptor antagonist (atrasentan) but was completely prevented by treatment with a combined ET(A) receptor and ET(B)R antagonist (A186280). These experiments reveal for the first time that chronic activation of ET(B)R in rats causes sustained hypertension.
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Affiliation(s)
- Gregory Fink
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA.
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36
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Wölkart G, Pang X, Stessel H, Kirchengast M, Brunner F. Chronic endothelin-A receptor antagonism is as protective as angiotensin converting enzyme inhibition against cardiac dysfunction in diabetic rats. Br J Pharmacol 2007; 151:1187-97. [PMID: 17572700 PMCID: PMC2189828 DOI: 10.1038/sj.bjp.0707325] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2007] [Revised: 04/23/2007] [Accepted: 05/02/2007] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE Diabetes mellitus is associated with a specific cardiomyopathy. We compared the cardioprotective effects of an endothelin-A receptor blocker (ET(A)-RB) with those of an angiotensin-converting enzyme inhibitor (ACE-I) in rats with streptozotocin (STZ)-induced diabetes. EXPERIMENTAL APPROACH Diabetic rats were left untreated or received either the ET(A)-RB atrasentan or the ACE-I ramipril (each 3 mg kg(-1) per day) orally for 8 weeks. Isolated isovolumic heart function was studied during normoxia and in response to ischaemia-reperfusion. Cardiac fibrosis, tissue oxidative stress and tissue nitric oxide synthase (NOS) activity were determined. KEY RESULTS Basal left ventricular systolic contractility was lower in diabetic compared to nondiabetic hearts and ET(A)-RB or ACE-I treatment significantly antagonised the decline. Following 15 min of no-flow ischaemia, reperfusion systolic function was depressed and left-ventricular end-diastolic pressure (LVEDP) was elevated in diabetic hearts. ET(A)-RB or ACE-I treatment significantly improved recovery of reperfusion systolic and diastolic function, without differences between groups. Hydroxyproline (an index of tissue fibrosis) and malondialdehyde (a measure of tissue oxidative stress) were elevated at the end of reperfusion in diabetic, compared to nondiabetic hearts. Either treatment reduced hydroxyproline and malondialdehyde to control level. Constitutive NOS activity was similar in nondiabetic and diabetic hearts and unaffected by ET(A)-RB or ACE-I treatment. CONCLUSIONS AND IMPLICATIONS These results suggest that in experimental type 1 diabetes ET(A)-RB is as effective as an ACE-I in ameliorating myocardial functions during normoxia and ischaemia-reperfusion. Combining the two treatments neither afforded additive effects, nor diminished any protection effect seen with either drug.
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Affiliation(s)
- G Wölkart
- Department of Pharmacology and Toxicology, University of Graz Graz, Austria
| | - X Pang
- Department of Pharmacology and Toxicology, University of Graz Graz, Austria
| | - H Stessel
- Department of Pharmacology and Toxicology, University of Graz Graz, Austria
| | - M Kirchengast
- PRA International Mannheim, Germany
- Faculty of Clinical Medicine, Department of Pharmacology and Toxicology, Mannheim Ruprecht-Karls-University Heidelberg Mannheim, Germany
| | - F Brunner
- Department of Pharmacology and Toxicology, University of Graz Graz, Austria
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37
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Shahani R, Fleshner NE, Zlotta AR. Pharmacotherapy for prostate cancer: the role of hormonal treatment. Discov Med 2007; 7:118-124. [PMID: 18093474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The role of hormonal therapy in the management of prostate cancer has been known for almost half a century. However, many controversies exist regarding the place and timing of androgen deprivation therapy. An increasing spectrum for the use of androgen deprivation therapy has been assessed, including multimodal treatment with radiation therapy. New approaches to androgen deprivation have been explored, including LHRH (luteinizing hormone-releasing hormone) antagonists and improved depot formulations. Recent evidence about the chemo-sensitivity of prostate cancer has opened avenues for treatment of hormone refractory disease and the combination of hormonal and chemotherapy is being studied at various stages of the disease. We explore the evidence, controversies and future of androgen deprivation therapy and critically reexamine the dogmas surrounding hormone therapy for prostate cancer.
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Affiliation(s)
- Rohan Shahani
- Division of Urology, Murray Koffler Urologic Wellness Centre, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
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Kawanishi H, Hasegawa Y, Nakano D, Ohkita M, Takaoka M, Ohno Y, Matsumura Y. Involvement of the endothelin ET(B) receptor in gender differences in deoxycorticosterone acetate-salt-induced hypertension. Clin Exp Pharmacol Physiol 2007; 34:280-5. [PMID: 17324138 DOI: 10.1111/j.1440-1681.2007.04580.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
1. In the present study, we investigated the role of endothelin ET(B) receptors in gender differences in the development of deoxycorticosterone acetate (DOCA)-salt-induced hypertension by using the spotting-lethal (sl) rat, which carries a naturally occurring deletion in the ET(B) receptor gene. 2. In wild-type rats, the elevation of systolic blood pressure (SBP) by DOCA-salt treatment for 4 weeks was extremely lower in females than in males, but this gender difference was partially attenuated in ovariectomized (OVX) animals. These alterations of SBP corresponded with vascular superoxide () production. 3. In homozygous (sl/sl) group, the SBP of male, intact female and OVX rats was markedly elevated by DOCA-salt treatment to the same extent, indicating that the gender difference in DOCA-salt-induced hypertension was abolished by the genetic ET(B) receptor deficiency. There were similar increases in the vascular endothelin (ET)-1 content in the three DOCA-salt-treated animal groups, but vascular production in male and OVX rats was much higher than that in intact females. 4. Daily oral administration of ABT-627, an ET(A) receptor antagonist, to sl/sl rats for 2 weeks suppressed the DOCA-salt-induced hypertension more efficiently in intact female rats than in male animals. 5. Thus, vascular oxidative stress is related, at least in part, to differences in the development of DOCA-salt-induced hypertension between male and female rats, but this gender difference is abolished by the genetic ET(B) receptor deficiency, suggesting that ET(B) receptor-mediated vasoprotective actions contribute to the gender differences seen. In addition, in both sexes, vascular ET-1 overproduction and the ET(A) receptor-mediated action seem to be responsible for the enhanced susceptibility to DOCA-salt hypertension in genetic ET(B) receptor deficiency.
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Affiliation(s)
- Hideaki Kawanishi
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
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Elgebaly MM, Portik-Dobos V, Sachidanandam K, Rychly D, Malcom D, Johnson MH, Ergul A. Differential effects of ET(A) and ET(B) receptor antagonism on oxidative stress in type 2 diabetes. Vascul Pharmacol 2007; 47:125-30. [PMID: 17597010 DOI: 10.1016/j.vph.2007.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2007] [Revised: 04/27/2007] [Accepted: 05/16/2007] [Indexed: 11/28/2022]
Abstract
Endothelin (ET-1) is chronically elevated in diabetes. However, role of ET-1 in increased oxidative stress in type 2 diabetes is less clear. This study tested the hypotheses that: 1) oxidative stress markers are increased and total antioxidant capacity is decreased in diabetes, and 2) activation of ET(A) receptors mediates oxidative stress whereas ET(B) receptors display opposing effects. Plasma total antioxidant status (TAS) and 8-isoprostane (8-iso PGF(2alpha)) as well as total nitrotyrosine levels in mesenteric resistance vessels were measured in control Wistar and diabetic Goto-Kakizaki (GK) rats (n=5-10) treated with vehicle, ET(A) antagonist (atrasentan, 5 mg/kg/day), or ET(B) receptor antagonist (A-192621, 15 or 30 mg/kg/day, low and high dose, respectively) for 4 weeks. 8-iso PGF(2alpha) (pg/ml) levels were significantly higher in low dose A-192621 treatment groups of control and diabetic rats than in atrasentan or high-dose A-192621 treated groups. Protein nitration was increased in diabetes and ET(A) receptor antagonism prevented this increase. TAS levels were similar in all experimental groups. Thus, ET-1 contributes to oxidative stress in type 2 diabetes and ET receptor antagonism with atrasentan or A-192612 displays differential effects depending on dose and receptor subtype.
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Affiliation(s)
- Mostafa M Elgebaly
- Program in Clinical and Experimental Therapeutics, Medical College of Georgia, Augusta, Georgia, USA
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Xiong H, Carr RA, Locke CS, Katz DA, Achari R, Doan TT, Wang P, Jankowski JR, Sleep DJ. Dual effects of rifampin on the pharmacokinetics of atrasentan. J Clin Pharmacol 2007; 47:423-9. [PMID: 17389551 DOI: 10.1177/0091270007299928] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effect of rifampin, a cytochrome P450 3A4 inducer, on the pharmacokinetics of atrasentan was assessed in 12 healthy male subjects in an open-label study. Single doses of atrasentan 10 mg were administered orally on days 1 and 12. Rifampin 600 mg was given once daily from days 4 through 14. On day 12, atrasentan and rifampin were administered simultaneously. Blood samples were collected before and during 72 hours after each atrasentan dose. On average, rifampin increased atrasentan peak plasma concentrations by 150% and reduced its terminal half-life by 77% (P<.05), without affecting the AUC or peak time of atrasentan. Rifampin may affect atrasentan pharmacokinetics by acting as both an inhibitor of organic anion transporting polypeptide-mediated hepatic uptake of atrasentan and an inducer of atrasentan metabolism. The effect of rifampin on atrasentan pharmacokinetics may depend on the time of rifampin administration relative to that of atrasentan.
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Affiliation(s)
- Hao Xiong
- Department of Clinical Pharmacokinetics, Abbott Laboratories, 100 Abbott Park Road, Dept. R4PK, AP13A-3, Abbott Park, IL 60064-6104, USA.
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Banes-Berceli AKL, Ketsawatsomkron P, Ogbi S, Patel B, Pollock DM, Marrero MB. Angiotensin II and endothelin-1 augment the vascular complications of diabetes via JAK2 activation. Am J Physiol Heart Circ Physiol 2007; 293:H1291-9. [PMID: 17526654 DOI: 10.1152/ajpheart.00181.2007] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The JAK/STAT pathway is activated in vitro by angiotensin II (ANG II) and endothelin-1 (ET-1), which are implicated in the development of diabetic complications. We hypothesized that ANG II and ET-1 activate the JAK/STAT pathway in vivo to participate in the development of diabetic vascular complications. Using male Sprague-Dawley rats, we performed a time course study [days 7, 14, and 28 after streptozotocin (STZ) injection] to determine changes in phosphorylation of JAK2, STAT1, and STAT3 in thoracic aorta using standard Western blot techniques. On day 7 there was no change in phosphorylation of JAK2, STAT1, and STAT3. Phosphorylation of JAK2, STAT1, and STAT3 was significantly increased on days 14 and 28 and was inhibited by treatment with candesartan (AT(1) receptor antagonist, 10 mg x kg(-1) x day(-1) orally in drinking water), atrasentan (ET(A) receptor antagonist, 10 mg x kg(-1) x day(-1) orally in drinking water), and AG-490 (JAK2 inhibitor, 5 mg x kg(-1) x day(-1) intraperitoneally). On day 28, treatment with all inhibitors prevented the significant increase in systolic blood pressure (SBP; tail cuff) of STZ-induced diabetic rats (SBP: 157 +/- 9.0, 130 +/- 3.3, 128 +/- 6.8, and 131 +/- 10.4 mmHg in STZ, STZ-candesartan, STZ-atrasentan, and STZ-AG-490 rats, respectively). In isolated tissue bath studies, diabetic rats displayed impaired endothelium-dependent relaxation in aorta (maximal relaxation: 95.3 +/- 3.0, 92.6 +/- 7.4, 76.9 +/- 12.1, and 38.3 +/- 13.1% in sham, sham + AG-490, STZ + AG-490, and STZ rats, respectively). Treatment of rats with AG-490 restored endothelium-dependent relaxation in aorta from diabetic rats at 14 and 28 days of treatment. These results demonstrate that JAK2 activation in vivo participates in the development of vascular complications associated with STZ-induced diabetes.
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MESH Headings
- Angiotensin II/metabolism
- Angiotensin II Type 1 Receptor Blockers/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/enzymology
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/physiopathology
- Atrasentan
- Benzimidazoles/pharmacology
- Biphenyl Compounds
- Blood Glucose/metabolism
- Blood Pressure
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/enzymology
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/physiopathology
- Diabetic Angiopathies/enzymology
- Diabetic Angiopathies/etiology
- Diabetic Angiopathies/metabolism
- Diabetic Angiopathies/physiopathology
- Endothelin A Receptor Antagonists
- Endothelin-1/metabolism
- Enzyme Activation
- Intracellular Signaling Peptides and Proteins/metabolism
- Janus Kinase 2/antagonists & inhibitors
- Janus Kinase 2/metabolism
- Male
- Phosphorylation
- Protein Kinase Inhibitors/pharmacology
- Protein Tyrosine Phosphatase, Non-Receptor Type 1
- Protein Tyrosine Phosphatase, Non-Receptor Type 11
- Protein Tyrosine Phosphatase, Non-Receptor Type 6/metabolism
- Protein Tyrosine Phosphatases/metabolism
- Pyrrolidines/pharmacology
- Rats
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, Endothelin A/metabolism
- STAT1 Transcription Factor/metabolism
- STAT3 Transcription Factor/metabolism
- Signal Transduction
- Tetrazoles/pharmacology
- Time Factors
- Tyrphostins/pharmacology
- Vasodilation
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Affiliation(s)
- Amy K L Banes-Berceli
- Vascular Biology Center, Department of Physiology, Medical College of Georgia, Augusta, GA 30912-3000, USA.
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Banerjee S, Hussain M, Wang Z, Saliganan A, Che M, Bonfil D, Cher M, Sarkar FH. In vitro and in vivo molecular evidence for better therapeutic efficacy of ABT-627 and taxotere combination in prostate cancer. Cancer Res 2007; 67:3818-26. [PMID: 17440096 DOI: 10.1158/0008-5472.can-06-3879] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Bone is the key metastatic site for prostate cancer. Endothelin 1 (ET-1) produced abundantly by prostate cancer cells binds to its receptor present on bone marrow stromal cells and favors osteoblastic response during bone metastases of prostate cancer. This suggests that interrupting ET-1 interaction with its endothelin A (ET(A)) receptor could be useful for inhibiting prostate cancer bone metastasis and, as such, may enhance the therapeutic activity of docetaxel (Taxotere), the most commonly used drug for the treatment of metastatic prostate cancer. Therefore, the goal of our study was to obtain preclinical data supporting our hypothesis that the combined use of ET(A) receptor antagonist (ABT-627; Atrasentan) with Taxotere will be superior in inducing apoptosis in vitro and inhibiting tumor growth in vivo in a SCID-hu model of experimental bone metastasis induced by C4-2b prostate cancer cells. In vitro studies were done on a panel of prostate cancer cell lines to understand the molecular basis of combination therapy, and we found that the combination was more effective in the inhibition of cell viability and induction of apoptosis in LNCaP and C4-2b cells (androgen receptor positive) but not in PC-3 cells. These results were correlated with inactivation of Akt/nuclear factor-kappaB and its target genes. For in vivo studies, the therapeutic regimen was initiated when the tumor began showing signs of growth and treatment was continued for 5 weeks. Tumor volume and serum prostate-specific antigen were used as terminal index to evaluate the therapeutic advantage of combination therapy relative to a single regimen and untreated control. At termination, we found a 90% reduction in tumor volume by combination treatment relative to the untreated control group. Most importantly, the antitumor activity was associated with the down-regulation of molecular markers in tumor tissues that were similar to those observed in vitro.
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Affiliation(s)
- Sanjeev Banerjee
- Department of Pathology, Barbara Ann Karmanos Cancer Institute, 4160 John R Street, Detroit, MI 48201, USA
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Sauvageau S, Thorin E, Caron A, Dupuis J. Endothelin-1-induced pulmonary vasoreactivity is regulated by ET(A) and ET(B) receptor interactions. J Vasc Res 2007; 44:375-81. [PMID: 17495482 DOI: 10.1159/000102534] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Accepted: 03/02/2007] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Roles of endothelin (ET) receptors (R) and of the endothelium on ET-1-induced pulmonary vasoreactivity are subjects of debate. This stems from endothelial ET(B)-R that can release both vasodilators and vasoconstrictors. The aim of this study was to evaluate the roles of the endothelium and of ET-Rs on ET-1-induced pulmonary vasoreactivity. METHODS Pharmacological experiments were performed in isolated rat lungs and in pulmonary resistance arteries. RESULTS In isolated lungs, ET-1 and the selective ET(B)-R agonist sarafotoxin 6c (S6c) induced a similar vasoconstriction. ET-1 constriction was reduced by a selective ET(A)-R antagonist; however, the selective ET(B)-R antagonist had no significant effect. In preconstricted lungs, ET(B)-R stimulation caused mild vasodilation at low concentrations but severe vasoconstriction at higher concentrations. In isolated arteries, responses to ET-1 and S6c were not different and unaffected by removal of endothelium. Interestingly, concentrations of ET(A)-R and ET(B)-R antagonists that only mildly reduced ET-1 vasoconstriction when used alone, prevented maximal constriction and greatly reduced vascular sensitivity to ET-1 when used in combination. CONCLUSION In rat lungs, both ET(A)-R and ET(B)-R contribute to ET-1-induced pulmonary vasoconstriction with evidence of interaction between receptors. A mild vasodilator role of the endothelial ET(B)-R is evident only at low agonist concentration and when baseline vascular tone is increased.
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van der Bilt JDW, Soeters ME, Duyverman AMMJ, Nijkamp MW, Witteveen PO, van Diest PJ, Kranenburg O, Borel Rinkes IHM. Perinecrotic hypoxia contributes to ischemia/reperfusion-accelerated outgrowth of colorectal micrometastases. Am J Pathol 2007; 170:1379-88. [PMID: 17392176 PMCID: PMC1829470 DOI: 10.2353/ajpath.2007.061028] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Ischemia/reperfusion (I/R) is often inevitable during hepatic surgery and may stimulate the outgrowth of colorectal micrometastases. Postischemic microcirculatory disturbances contribute to I/R damage and may induce prolonged tissue hypoxia and consequent stabilization of hypoxia-inducible factor (HIF)-1alpha. The aim of this study was to evaluate the contribution of postischemic microcirculatory disturbances, hypoxia, and HIF-1alpha to I/R-accelerated tumor growth. Partial hepatic I/R attributable to temporary clamping of the left liver lobe induced microcirculatory failure for up to 5 days. This was accompanied by profound and prolonged perinecrotic tissue hypoxia, stabilization of HIF-1alpha, and massive perinecrotic outgrowth of pre-established micrometastases. Restoration of the microcirculation by treatment with Atrasentan and L-arginine minimized hypoxia and HIF-1alpha stabilization and reduced the accelerated outgrowth of micrometastases by 50%. Destabilization of HIF-1alpha by the HSP90 inhibitor 17-DMAG caused an increase in tissue necrosis but reduced I/R-stimulated tumor growth by more than 70%. In conclusion, prevention of postischemic microcirculatory disturbances and perinecrotic hypoxia reduces the accelerated outgrowth of colorectal liver metastases after I/R. This may, at least in part, be attributed to the prevention of HIF-1alpha stabilization. Prevention of tissue hypoxia or inhibition of HIF-1alpha may represent attractive approaches to limiting recurrent tumor growth after hepatic surgery.
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45
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Smollich M, Götte M, Kersting C, Fischgräbe J, Kiesel L, Wülfing P. Selective ETAR antagonist atrasentan inhibits hypoxia-induced breast cancer cell invasion. Breast Cancer Res Treat 2007; 108:175-82. [PMID: 17468950 DOI: 10.1007/s10549-007-9589-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Accepted: 03/30/2007] [Indexed: 11/26/2022]
Abstract
Tumour hypoxia, being widespread in solid tumours, is related to an increased risk of invasion and metastasis as well as to resistance to chemotherapy and radiotherapy. Hypoxia-inducible factor-1alpha (HIF-1alpha) has emerged as the key regulator of the cellular response to hypoxia. In primary breast cancers, HIF-1alpha is overexpressed, and high levels of HIF-1alpha predict for early relapse and increased metastasis. The endothelin (ET) axis, comprising the peptides ET-1, -2, -3 and their receptors A (ETAR) and B (ETBR), is another regulatory system of major relevance in human breast cancer. However, little is known about the interaction of HIF-1alpha and the ET axis in breast carcinomas. Therefore, we analysed expression of HIF-1alpha and the ET axis in 600 breast cancer tissue samples by immunohistochemistry, observing a significant correlation between expression of HIF-1alpha and ET-1 (P<0.001). In vitro, hypoxia was found to double ET-1 secretion of MCF-7 breast cancer cells (203.5% of controls; P<0.001), thereby promoting an invasive phenotype. Of note, real-time PCR analysis revealed that the increase of ET-1 was not due to enhanced transcription of the ET-1 gene. In invasion assays, breast cancer cell invasiveness was strongly increased by hypoxia (150.0% of controls; P=0.007). Most important, this increase was completely inhibited by the selective ETAR antagonist atrasentan. In conclusion, we provide evidence for a relevant interaction between hypoxia and the ET axis in breast cancer cells. Our data suggest that tumour hypoxia induces breast carcinoma invasiveness by releasing intracellularly stored ET-1. However, induction of invasiveness may be inhibited by selective ETAR antagonism, thus emphasising the promising status of the ET axis as a therapeutic target in breast cancer.
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Affiliation(s)
- M Smollich
- Department of Obstetrics and Gynecology, University Hospital of Münster, Albert-Schweitzer-Str. 33, 48149, Münster, Germany
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46
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Sasser JM, Sullivan JC, Hobbs JL, Yamamoto T, Pollock DM, Carmines PK, Pollock JS. Endothelin A receptor blockade reduces diabetic renal injury via an anti-inflammatory mechanism. J Am Soc Nephrol 2006; 18:143-54. [PMID: 17167119 PMCID: PMC2579758 DOI: 10.1681/asn.2006030208] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Endothelin (ET) receptor blockade delays the progression of diabetic nephropathy; however, the mechanism of this protection is unknown. Therefore, the aim of this study was to test the hypothesis that ET(A) receptor blockade attenuates superoxide production and inflammation in the kidney of diabetic rats. Diabetes was induced by streptozotocin (diabetic rats with partial insulin replacement to maintain modest hyperglycemia [HG]), and sham rats received vehicle treatments. Some rats also received the ETA antagonist ABT-627 (sham+ABT and HG+ABT; 5 mg/kg per d; n = 8 to 10/group). During the 10-wk study, urinary microalbumin was increased in HG rats, and this effect was prevented by ET(A) receptor blockade. Indices of oxidative stress, urinary excretion of thiobarbituric acid reactive substances, 8-hydroxy--deoxyguanosine, and H2O2 and plasma thiobarbituric acid reactive substances were significantly greater in HG rats than in sham rats. These effects were not prevented by ABT-627. In addition, renal cortical expression of 8-hydroxy--deoxyguanosine and NADPH oxidase subunits was not different between HG and HG+ABT rats. ETA receptor blockade attenuated increases in macrophage infiltration and urinary excretion of TGF-beta and prostaglandin E2 metabolites in HG rats. Although ABT-627 did not alleviate oxidative stress in HG rats, inflammation and production of inflammatory mediators were reduced in association with prevention of microalbuminuria. These observations indicate that ETA receptor activation mediates renal inflammation and TGF-beta production in diabetes and are consistent with the postulate that ETA blockade slows progression of diabetic nephropathy via an anti-inflammatory mechanism.
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Affiliation(s)
- Jennifer M. Sasser
- Vascular Biology Center and Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA
| | - Jennifer C. Sullivan
- Vascular Biology Center and Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA
| | - Janet L. Hobbs
- Vascular Biology Center and Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA
| | - Tatsuo Yamamoto
- First Department of Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - David M. Pollock
- Vascular Biology Center and Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA
| | - Pamela K. Carmines
- Department of Cellular and Integrative Physiology, University of Nebraska College of Medicine, Omaha, NE
| | - Jennifer S. Pollock
- Vascular Biology Center and Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA
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Mai HQ, Zeng ZY, Feng KT, Ye YL, Zhang CQ, Liang WJ, Guo X, Mo HY, Hong MH. Therapeutic targeting of the endothelin a receptor in human nasopharyngeal carcinoma. Cancer Sci 2006; 97:1388-95. [PMID: 17032313 DOI: 10.1111/j.1349-7006.2006.00333.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The endothelin A receptor (ET(A)R) autocrine pathway is overexpressed in many malignancies, including nasopharyngeal carcinoma (NPC). In this tumor, ET(A)R expression is an independent determinant of survival and a robust independent predictor of distant metastasis. To evaluate whether ET(A)R represents a new target in NPC treatment, we tested the therapeutic role of ET(A)R in NPC. Cell proliferation was inhibited by the ET(A)R-selective antagonist ABT-627 in two ET(A)R-positive NPC cells in a dose-dependent manner. Proliferation of ET(A)R-negative NPC cells was not decreased. ET(A)R blockade also resulted in sensitization to cisplatin and 5-fluorouracil-induced apoptosis. In nude mice, ABT-627 inhibited the growth of NPC cell xenografts. Combined treatment of ABT-627 with the cytotoxic drug cisplatin or 5-fluorouracil produced additive antitumor effects. The antitumor activity of ABT-627 was demonstrated finally on an experimental lung metastasis by a reduction in the number of tumors. These results support the rationale of combining ABT-627 with current standard chemotherapy to further improve the therapeutic ratio in the treatment of NPC.
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MESH Headings
- Animals
- Antimetabolites, Antineoplastic/therapeutic use
- Antineoplastic Agents/therapeutic use
- Apoptosis/drug effects
- Atrasentan
- Cell Proliferation/drug effects
- Cisplatin/therapeutic use
- Disease Models, Animal
- Drug Therapy, Combination
- Endothelin A Receptor Antagonists
- Endothelin B Receptor Antagonists
- Endothelin-1/metabolism
- Fluorouracil/therapeutic use
- Humans
- Lung Neoplasms/drug therapy
- Lung Neoplasms/metabolism
- Lung Neoplasms/secondary
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Nasopharyngeal Neoplasms/drug therapy
- Nasopharyngeal Neoplasms/metabolism
- Nasopharyngeal Neoplasms/pathology
- Pyrrolidines/therapeutic use
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- Receptor, Endothelin A/genetics
- Receptor, Endothelin A/metabolism
- Receptor, Endothelin B/genetics
- Receptor, Endothelin B/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Tumor Cells, Cultured
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Hai-Qiang Mai
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China
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48
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Abstract
Recent advances in the understanding of prostate cancer biology and its progression to bone metastasis have led to the development of drugs directed against precise molecular alterations in the prostate tumor cell and host cells in the normal bone environment such as osteoclasts and osteoblasts. Endothelins (ETs) and their receptors have emerged as a potential target in prostate cancer bone metastasis. By activating the ETA receptor, ET-1 is pathogenically involved in facilitating several aspects of prostate cancer progression, including proliferation, escape from apoptosis, invasion, and new bone formation, processes that are general to many malignancies. Notwithstanding, there are a number of features specifically driven by the ET axis in prostate cancer, such as creating and perpetuating a unique interaction between the metastatic prostate cancer cell and the bone microenvironment (osteoblast, osteoclast, and stroma) or altering the equilibrium in pain modulation. These features have led to the preferential clinical evaluation of atrasentan (ABT-627) as a biological therapy in prostate carcinoma, first in hormone-refractory prostate cancer. Biological activity of atrasentan in patients with prostate cancer has been shown by the suppression of biochemical markers of prostate cancer progression in bone, and clinical activity is evidenced by a consistent trend demonstrating a delay in time to disease progression when compared with placebo, especially in patients with bone metastases. Further studies of atrasentan and other selective ET-1 antagonists (ZD4054) are ongoing.
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Affiliation(s)
- Michael A Carducci
- Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland 21231-1000, USA.
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49
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Chade AR, Krier JD, Textor SC, Lerman A, Lerman LO. Endothelin-a receptor blockade improves renal microvascular architecture and function in experimental hypercholesterolemia. J Am Soc Nephrol 2006; 17:3394-403. [PMID: 17082239 DOI: 10.1681/asn.2006060635] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Hypercholesterolemia (HC) may trigger early renal injury, partly by impairing the function or the structure of renal microvessels (MV). The endothelin (ET) system is upregulated in HC and can have an impact on the renal microcirculation by regulating MV tone, growth factors, and remodeling. It was hypothesized that ET-A blockade would protect the HC kidney by improving the function and attenuating the damage of intrarenal MV. Single-kidney function and hemodynamic responses to endothelium-dependent challenge were assessed in pigs after 12 wk of experimental HC, HC and chronic supplementation with the ET receptor A blocker ABT-627 (HC+ET-A, 0.75 mg/kg per d), and normal controls. Renal MV architecture then was studied ex vivo using three-dimensional microcomputed tomography imaging, and growth factors and remodeling pathways were explored in renal tissue. The HC kidney showed increased MV density compared with normal (77.68 +/- 5.1 versus 62.9 +/- 4.8 vessels/cm(2); P = 0.04) but blunted endothelial function. Chronic ET-A blockade in HC upregulated renal vascular growth factors, further increased renal MV density (139.9 +/- 8.4 vessels/cm(2); P = 0.001 versus normal and HC), and decreased renal tissue and MV remodeling. Furthermore, ET-A blockade in HC decreased MV tortuosity and improved MV endothelial function, suggesting accelerated stabilization and maturation of neo-vessels. Modulation of renal MV architecture and function in HC is mediated partly by the endogenous ET system. Notably, ET-A blockade enhanced the proliferation and facilitated the maturation of renal MV in the HC kidney and improved renal MV remodeling and function. This study suggests novel renoprotective effects of ET-A blockers and supports further exploration of strategies that target the ET pathway in HC and atherosclerosis.
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Affiliation(s)
- Alejandro R Chade
- Department of Internal Medicine, Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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Michaelson MD, Kaufman DS, Kantoff P, Oh WK, Smith MR. Randomized phase II study of atrasentan alone or in combination with zoledronic acid in men with metastatic prostate cancer. Cancer 2006; 107:530-5. [PMID: 16804927 DOI: 10.1002/cncr.22043] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Metastatic prostate cancer is characterized by the presence of osteoblastic bone metastases. Bone metastases account for most of the morbidity from this disease. Inhibition of osteoclast activity with the potent bisphosphonate zoledronic acid reduces skeletal complications and decreases serum levels of biochemical bone turnover markers compared with placebo. Atrasentan is an investigational agent that inhibits endothelin-1 receptor, resulting in decreased osteoblast activity. METHODS The effects of atrasentan alone versus combination therapy with atrasentan and zoledronic acid were investigated on bone turnover markers in men with bone metastases from prostate cancer. Forty-four men were randomized to receive either atrasentan alone or combination therapy, and 33 completed at least 12 weeks of treatment and were included in the primary analysis. RESULTS Treatment with the combination resulted in significantly lower serum levels of N-telopeptide, a marker of bone resorption, compared with treatment with atrasentan alone. There was no difference between groups in serum levels of bone-specific alkaline phosphatase, a marker of bone formation, at 12 weeks. Commonly observed adverse effects were edema, rhinitis, fatigue, and shortness of breath, most of which were NCI CTC (version 3.0) Grade 1. No Grade 4 or 5 treatment-related toxicities were observed. There was minimal clinical efficacy, with no objective responses and only 1 prostate-specific antigen (PSA) response. CONCLUSIONS There is no evidence for additive or synergistic effects of combination therapy with atrasentan and zoledronic acid on bone turnover markers in men with metastatic prostate cancer.
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Affiliation(s)
- M Dror Michaelson
- Department of Hematology/Oncology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
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