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Dietary Effects of Chromium Picolinate and Chromium Nanoparticles in Wistar Rats Fed with a High-Fat, Low-Fiber Diet: The Role of Fat Normalization. Nutrients 2022; 14:nu14235138. [PMID: 36501167 PMCID: PMC9741435 DOI: 10.3390/nu14235138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/24/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
We aimed to evaluate how feeding a high-fat-low-fiber (F) diet to rats and dietary intervention with the implementation of a standard-fat-and-fiber (S) diet affects the response of the cardiovascular system to chromium (III) picolinate (Cr-Pic) and, alternatively, chromium nanoparticles (Cr-NPs). Young male Wistar Han rats (n/group = 12) from either the fatty group (18 weeks on F diet) or the intervention group (9 weeks on F diet + 9 weeks on S diet) received a pharmacologically relevant dose of 0.3 mg Cr/kg body weight in the form of Cr-Pic or Cr-NPs for 9 weeks. Our study on rats confirmed the pro-inflammatory effect of an F diet administered for 18 weeks. In the intervention group, both Cr-Pic and Cr-NPs decreased heart glutathione ratio (GSH+GSSG), enhanced participation of nitric oxide (NO) derived from inducible NO synthase (iNOS) in vascular relaxation to acetylcholine (ACh), increased the vasodilator net effect of cyclooxygenase-2 (COX-2)-derived prostanoids, and increased the production of superoxide anion (O2.-) in aortic rings. Meanwhile, in the fatty group, there was increased heart superoxide dismutase (SOD), decreased heart catalase (CAT), and reduced sensitivity in pre-incubated aortic rings to endogenous prostacyclin (PGI2). The factors that significantly differentiated Cr-NPs from Cr-Pic were (i) decreased blood antioxidant capacity of water-soluble compounds (0.75-fold, p = 0.0205), (ii) increased hydrogen peroxide (H2O2) production (1.59-fold, p = 0.0332), and (iii) modified vasodilator response due to PGI2 synthesis inhibition (in the intervention group) vs. modified ACh-induced vasodilator response due to (iv) COX inhibition and v) PGI2 synthesis inhibition with thromboxane receptor blockage after 18 weeks on F diet (in the fatty group). Our results show that supplementation with Cr-Pic rather than with Cr-NPs is more beneficial in rats who regularly consumed an F diet (e.g., for 18 weeks). On the contrary, in the intervention group (9 weeks on F diet + 9 weeks of dietary fat normalization (the S diet)), Cr-Pic and Cr-NPs could function as pro-oxidant agents, initiating free-radical reactions that led to oxidative stress.
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Chies AB, Spadella MA, Carlos CP, Pacheco da Silva CB, Tirapelli CR. Orchiectomy but not adjuvant-induced arthritis induces structural modifications in rat aortas. J Smooth Muscle Res 2022; 58:63-77. [PMID: 35944980 PMCID: PMC9364264 DOI: 10.1540/jsmr.58.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Purpose: This study aimed to verify whether Adjuvant-Induced Arthritis (AIA) and/or
Orchiectomy (ORX) modify the expression of the Nox1, Nox2 and Nox4 isoforms, the
endothelial function or the structure of rat aortas. Methods: Sixty-three Wistar rats were
distributed into four groups: 1) Control; 2) ORX; 3) AIA; 4) Orchiectomy plus to
Arthritis-induction (ORX/AIA). Thus, 21 days after the onset of AIA (by intradermal
injection of Mycobacterium tuberculosis), the presence of Nox1, Nox2 and
Nox4, the acetylcholine (ACh)-induced relaxation and the media layer thickness were
assessed in the aorta taken from these animals. Results: The Nox1, Nox2 and Nox4 were
immunostained in intima, media and adventitia layers of aortas taken from all studied
groups and AIA apparently increased this immunostaining. These modifications of Nox1, Nox2
or Nox4 expression, however, were not confirmed by Western blotting. In addition, neither
AIA nor ORX changed the endothelial function, but ORX increased the media layer thickness
in the studied aortas. Conclusion: The present study showed weak clues of increased
expression of Nox1, Nox2 and Nox4 as a result of AIA, as well as of Nox1 reduction caused
by ORX. In addition, the endothelial function was not modified in the aortas of these
animals by both AIA and/or ORX. On the other hand, ORX increased significantly the aorta
media layer thickness in the studied animals, which was apparently mitigated by AIA.
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Affiliation(s)
- Agnaldo Bruno Chies
- Laboratory of Pharmacology, Marília Medical School, Av. Monte Carmelo, 800, Fragata, Marília, São Paulo 17 519-030, Brazil
| | - Maria Angélica Spadella
- Laboratory of Human Embryology, Marília Medical School, Av. Monte Carmelo, 800, Fragata, Marília, São Paulo 17 519-030, Brazil
| | - Carla Patrícia Carlos
- Laboratory of Experimental Research, FACERES School of Medicine, Jardim Morumbi, São José do Rio Preto, São Paulo 15090-305, Brazil
| | | | - Carlos Renato Tirapelli
- Laboratório de Farmacologia, DEPCH, Escola de Enfermagem de Ribeirão Preto, USP, Ribeirão Preto, São Paulo, Brazil
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Teoh JYC, Tian XY, Wong CYP, Lau CW, Cheng CK, Tang VWL, Chan RCK, Huang Y, Ng CF. Endothelial dysfunction after androgen deprivation therapy and the possible underlying mechanisms. Prostate 2022; 82:13-25. [PMID: 34570375 DOI: 10.1002/pros.24244] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/28/2021] [Accepted: 09/12/2021] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Androgen deprivation therapy (ADT) is a key treatment modality in the management of prostate cancer (PCa), especially for patients with metastatic disease. Increasing evidences suggest that patients who received ADT have increased incidence of diabetes, myocardial infarction, stroke, and even mortality. It is important to understand the pathophysiological mechanisms on how ADT increases cardiovascular risk and induces cardiovascular events, which would provide important information for potential implementation of preventive measures. METHODS Twenty-six 12-week-old male SD rats were divided into four groups for different types of ADTs including: the bilateral orchidectomy group (Orx), LHRH agonist group (leuprolide), LHRH antagonist group (degarelix), and control group. After treated with drug or adjuvant injection every 3 weeks for 24 weeks, all rats were sacrificed and total blood were collected. Aorta, renal arteries, and kidney were preserved for functional assay, immunohistochemistry, western blot, and quantitative reverse-transcription polymerase chain reaction. RESULTS In vascular reactivity assays, aorta, intrarenal, and coronary arteries of all three ADT groups showed endothelial dysfunction. AT1R and related molecules at protein and messenger RNA (mRNA) level were tested, and AT1R pathway was shown to be activated and played a role in endothelial dysfunction. Both ACE and AT1R mRNA levels were doubled in the aorta in the leuprolide group while Orx and degarelix groups showed upregulation of AT1R in the kidney tissues. By immunohistochemistry, our result showed higher expression of AT1R in the intrarenal arteries of leuprolide and degarelix groups. The role of reactive oxygen species in endothelial dysfunction was confirmed by DHE fluorescence, nitrotyrosine overexpression, and upregulation of NOX2 in the different ADT treatment groups. CONCLUSION ADT causes endothelial dysfunction in male rats. GnRH receptor agonist compared to GnRH receptor antagonist, showed more impairment of endothelial function in the aorta and intrarenal arteries. Such change might be associated with upregulation and activation of AngII-AT1R-NOX2 induced oxidative stress in the vasculature. These results help to explain the different cardiovascular risks and outcomes related to different modalities of ADT treatment.
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Affiliation(s)
- Jeremy Yuen-Chun Teoh
- S.H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China
| | - Xiao-Yu Tian
- Institute of Vascular Medicine, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Christine Yim-Ping Wong
- S.H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China
| | - Chi-Wai Lau
- Institute of Vascular Medicine, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Chak-Kwong Cheng
- Institute of Vascular Medicine, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Victor Wai-Lun Tang
- Department of Clinical Pathology, Pamela Youde Nethersole Eastern Hospital, Hong Kong, China
| | - Ronald Cheong-Kin Chan
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Yu Huang
- Institute of Vascular Medicine, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Chi-Fai Ng
- S.H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China
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Rojas MM, Villalpando DM, Alexander-Aguilera A, Ferrer M, García HS. Effect of CLA supplementation on factors related to vascular dysfunction in arteries of orchidectomized rats. Prostaglandins Other Lipid Mediat 2021; 157:106586. [PMID: 34438054 DOI: 10.1016/j.prostaglandins.2021.106586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 01/22/2023]
Abstract
The vascular endothelium is a monolayer of flat epithelial cells located between the circulating blood and the underlying connective tissue. It conveys key functions that when impaired, lead to endothelial dysfunction. This condition is responsible for the pathogenesis of vascular diseases. The cardioprotective effect of sex hormones is widely known; hence, a murine orchidectomized model has been employed to study the effects caused by their deficiency. In the search for approaches to maintain vascular health, the effect of dietary fatty acids as CLA on cardiovascular diseases has been studied. Some proven beneficial properties of CLA are antioxidant, antiatherogenic and anti-inflammatory. Our objective was to evaluate the effect of a diet supplemented with 1.8 % (w/w) of CLA, administered during eight weeks, on the amount of cholesterol oxidation products (COPs) produced by orchidectomy and on factors related to vascular dysfunction in the aorta and the mesenteric arteries. The diet with CLA prevented the increase in prostanoids formation and maintained the normal physiological conditions of NO and antioxidant activity. In addition, it prevented the increase in cholesterol and COPs at the vascular wall. CLA-supplemented diet prevented the orchidectomy-induced alterations on prostanoids, NO and COPs and also improved the antioxidant activity. These findings could contribute to understand the mechanisms of actions of CLA involved in the prevention of cardiovascular diseases.
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Affiliation(s)
- Mibsam M Rojas
- Food Research and Development Unit, National Technology of Mexico/Technological Institute of Veracruz, Ver., Mexico
| | - Diva M Villalpando
- Physiology Department, Faculty of Medicine, Autonomous University of Madrid, Madrid, Spain
| | | | - Mercedes Ferrer
- Physiology Department, Faculty of Medicine, Autonomous University of Madrid, Madrid, Spain.
| | - Hugo S García
- Food Research and Development Unit, National Technology of Mexico/Technological Institute of Veracruz, Ver., Mexico.
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Álvarez-Maestro M, Eguibar A, Chanca P, Klett-Mingo M, Gómez Rivas J, Buño-Soto A, de Bethencourt FR, Ferrer M. Androgen Deprivation Therapy in Patients With Prostate Cancer Increases Serum Levels of Thromboxane A 2: Cardiovascular Implications. Front Cardiovasc Med 2021; 8:653126. [PMID: 33928136 PMCID: PMC8076684 DOI: 10.3389/fcvm.2021.653126] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 03/15/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction: Androgens have been described as important players in the regulation of vascular function/structure through their action on the release and effect of vasoactive factors, such as prostanoids. Patients with prostate cancer (PCa) under androgen deprivation therapies (ADTs) present increased risk of cardiovascular mortality. Since thromboxane A2 (TXA2) is one of the most studied prostanoids and its involvement in different cardiovascular diseases has been described, the aim of this study was to investigate: (i) the effect of ADT on the serum levels of TXA2 in PCa patients and its possible link to the redox status and (ii) the effect of the non-hydrolyzable TXA2 analog U-46619 on the function of the aorta of male rats. Methods: The levels of TXA2 and total antioxidant status in 50 healthy subjects, 54 PCa patients, and 57 PCa under ADT were evaluated. These determinations were accompanied by levels of testosterone and C-reactive protein as an inflammation marker. In aortic segments from male rats, the U46619-induced effects on: (i) the vasomotor responses to acetylcholine (ACh), to the NO donor sodium nitroprusside (SNP), to the carbon monoxide-releasing molecule-3 (CORM-3), and to noradrenaline (NA) and (ii) the expression of cyclooxygenase-2 (COX-2), heme oxygenase-1 (HO-1), and phosphorylated ERK1/2 were analyzed. Results: The serum level of TXA2 in patients with PCa was increased with respect to healthy subjects, which was further increased by ADT. There was no modification in the total antioxidant status among the three experimental groups. In aortic segments from male rats, the TXA2 analog decreased the endothelium-dependent relaxation and the sensitivity of smooth muscle cells to NO, while it increased the vasoconstriction induced by NA; the expression of COX-2, HO-1, and pERK1/2 was also increased. Conclusions: ADT increased, along with other inflammatory/oxidative markers, the serum levels of TXA2. The fact that TXA2 negatively impacts the vascular function of the aorta of healthy male rats suggests that inhibition of TXA2-mediated events could be considered a potential strategy to protect the cardiovascular system.
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Affiliation(s)
- Mario Álvarez-Maestro
- Servicio de Urología, Hospital Universitario La Paz, Madrid, Spain.,Grupo de Investigación en Urología, IdiPAZ, Madrid, Spain
| | - Aritz Eguibar
- Servicio de Urología, Hospital Universitario La Paz, Madrid, Spain
| | - Patricia Chanca
- Servicio de Análisis Clínicos, Hospital Universitario La Paz, Madrid, Spain
| | | | - Juan Gómez Rivas
- Departamento de Urología, Hospital Clínico San Carlos, Madrid, Spain
| | - Antonio Buño-Soto
- Servicio de Análisis Clínicos, Hospital Universitario La Paz, Madrid, Spain.,Grupo de Investigación en Neonatología, IdiPAZ, Madrid, Spain
| | - Fermín R de Bethencourt
- Servicio de Urología, Hospital Universitario La Paz, Madrid, Spain.,Grupo de Investigación en Urología, IdiPAZ, Madrid, Spain
| | - Mercedes Ferrer
- Grupo de Investigación en Urología, IdiPAZ, Madrid, Spain.,Departamento de Fisiología, Facultad de Medicina, UAM, Madrid, Spain
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Isidoro-García L, Villalpando DM, Ferrer M. Vasomotor action of androgens in the mesenteric artery of hypertensive rats. Role of perivascular innervation. PLoS One 2021; 16:e0246254. [PMID: 33529222 PMCID: PMC7853503 DOI: 10.1371/journal.pone.0246254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 01/18/2021] [Indexed: 11/18/2022] Open
Abstract
Androgens may exert cardiovascular protective actions by regulating the release and function of different vascular factors. In addition, testosterone (TES) and its 5-reduced metabolites, 5α- and 5β-dihydrotestosterone (5α- and 5β-DHT) induce vasorelaxant and hypotensive effects. Furthermore, hypertension has been reported to alter the release and function of the neurotransmitters nitric oxide (NO), calcitonin gene-related peptide (CGRP) and noradrenaline (NA). Since the mesenteric arteries possess a dense perivascular innervation and significantly regulate total peripheral vascular resistance, the objective of this study was to analyze the effect of TES, 5α- and 5β-DHT on the neurogenic release and vasomotor function of NO, CGRP and NA. For this purpose, the superior mesenteric artery from male spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats was used to analyze: (i) the effect of androgens (10 nM, incubated for 30 min) on the neurogenic release of NO, CGRP and NA and (ii) the vasoconstrictor-response to NA and the vasodilator responses to the NO donor, sodium nitroprusside (SNP) and exogenous CGRP. The results showed that TES, 5α- or 5β-DHT did not modify the release of NO, CGRP or NA induced by electrical field stimulation (EFS) in the arteries of SHR; however, in the arteries of WKY rats androgens only caused an increase in EFS-induced NO release. Moreover, TES, and especially 5β-DHT, increased the vasodilator response induced by SNP and CGRP in the arteries of SHR. These findings could be contributing to the hypotensive/antihypertensive efficacy of 5β-DHT previously described in conscious SHR and WKY rats, pointing to 5β- DHT as a potential drug for the treatment of hypertension.
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Affiliation(s)
- Lucía Isidoro-García
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain
| | - Diva M. Villalpando
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain
| | - Mercedes Ferrer
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain
- Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
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Rojas MM, Villalpando DM, Ferrer M, Alexander‐Aguilera A, García HS. Conjugated Linoleic Acid Supplemented Diet Influences Serum Markers in Orchidectomized Sprague‐Dawley Rats. EUR J LIPID SCI TECH 2020. [DOI: 10.1002/ejlt.201900098] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Mibsam Margot Rojas
- UNIDA Tecnológico Nacional de Mexico/Instituto Tecnológico de Veracruz M. A. de Quevedo 2779, Colonia Formando Hogar Veracruz Veracruz 91897 México
| | - Diva María Villalpando
- Departamento de Fisiología, Facultad de Medicina Universidad Autónoma de Madrid C/Arzobispo Morcillo 4 Madrid 28029 Spain
| | - Mercedes Ferrer
- Departamento de Fisiología, Facultad de Medicina Universidad Autónoma de Madrid C/Arzobispo Morcillo 4 Madrid 28029 Spain
- Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid Spain
| | - Alfonso Alexander‐Aguilera
- Facultad de Bioanálisis Universidad Veracruzana Carmen Serdán s/n, Col. Flores Magón Veracruz 91700 México
| | - Hugo Sergio García
- UNIDA Tecnológico Nacional de Mexico/Instituto Tecnológico de Veracruz M. A. de Quevedo 2779, Colonia Formando Hogar Veracruz Veracruz 91897 México
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Villalpando DM, Gómez Rivas J, Flynn D, R de Bethencourt F, Ferrer M. Gonadal function protects against organ culture-induced vascular damage. Involvement of prostanoids. Prostaglandins Other Lipid Mediat 2020; 148:106406. [PMID: 31945460 DOI: 10.1016/j.prostaglandins.2019.106406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/25/2019] [Accepted: 12/23/2019] [Indexed: 02/03/2023]
Abstract
Androgen deprivation induces vascular dysfunction in which altered release and action of prostanoids has been extensively studied. On the other hand, the vascular organ-culture system has been reported as a valid model for phenotypic changes that occur in several cardiovascular pathologies. Since there are no studies analyzing the impact of androgenic loss on vascular vulnerability during induced vascular damage, the objective of this study was to analyze the possible preventive role of male sex hormones on the organ culture-induced vascular damage in rat aorta. The link to possible changes in gross structure was also analyzed. For this purpose, fresh and 20 h-cultured aortic arterial segments from intact and orchidectomized rats were used to analyze: (i) the release and vasomotor effect of the thromboxane A2 (TXA2), prostaglandin (PG) E2, PGF2α and PGI2; (ii) the vasodilator response induced by acetylcholine (ACh) as well as the involvement of prostanoids, in particular TXA2, in the ACh-induced response; (iii) the effect of activation of thromboxane/prostaglandin (TP) receptors on the ACh-induced response; and (iv) the vascular structure. The results showed that organ culture: i) increased production of prostanoids; ii) increased prostanoids-induced vasomotor responses; iii) decreased ACh-induced relaxation after incubation with indomethacin, a blocker of cyclooxygenases; iv) increased the ACh-induced relaxation after incubation with the TXA2 synthase inhibitor, furegrelate, more in arteries from orchidectomized rats than in those of intact rats; v) diminished ACh-induced relaxation after U-46619 incubation only in arteries from orchidectomized rats; and vi) preserved the integrity of the different vascular layers. These results showed the protective role of male sex hormones against the induced vascular damage, since a decreased deleterious effect of prostanoids, in particular that of TXA2, was observed in arteries from rats with intact gonadal function.
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Affiliation(s)
| | - Juan Gómez Rivas
- Servicio de Urología, Hospital Universitario La Paz, Madrid, Spain; Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain
| | - Daniel Flynn
- Departamento de Fisiología, Facultad de Medicina, UAM, Spain
| | - Fermín R de Bethencourt
- Servicio de Urología, Hospital Universitario La Paz, Madrid, Spain; Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain
| | - Mercedes Ferrer
- Departamento de Fisiología, Facultad de Medicina, UAM, Spain; Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain.
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Abstract
BACKGROUND Testosterone, 5α- and 5β-dihydrotestosterone (-DHT) induce an acute in vitro vasorelaxation and in vivo vasodepressor, hypotensive and antihypertensive responses. Our aim was to study whether androgen-induced blood pressure (BP) reduction is involved with a blockade of Ca2+ influx through L-type voltage-operated calcium channels (L-VOCCs) and/or the signaling pathways of α1-adrenoceptors to induce vasoconstriction, which are one of the major mechanisms of BP maintenance. MATERIALS AND METHODS The relaxing potency and efficacy of each androgen in large conduit (thoracic aorta) and resistance (mesenteric) arteries from male hypertensive (SHR) and normotensive (WKY) rats were established. Blood vessels were isometrically recorded and precontracted with KCl or phenylephrine (Phe). RESULTS Androgens induced concentration-dependent vasorelaxation in precontracted arteries from SHR and WKY rats. 5β-DHT was always the most potent vasorelaxant in arteries from SHR. The KCl-induced contraction resulted significantly more sensitive to androgen-induced vasorelaxation than the Phe-induced contraction. On Phe-induced contraction, 5β-DHT was more potent in the mesenteric artery than in the thoracic aorta. CONCLUSIONS The vasorelaxation induced by androgens is mainly mediated by blocking L-VOCCs and in lesser extent by the blockade of multiple signaling pathways operative during α-adrenoceptor-induced vasoconstriction. 5β-DHT regulates vascular resistance and BP by mainly acting in the mesenteric arterial bed, which may explain its outstanding antihypertensive response previously reported.
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Affiliation(s)
- Lucía Isidoro
- a Departamento de Fisiología, Facultad de Medicina , Universidad Autónoma de Madrid , Madrid , Spain
- b Instituto de Investigaciones Biomédicas, Departamento de Biología Celular y Fisiología , Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Mercedes Ferrer
- a Departamento de Fisiología, Facultad de Medicina , Universidad Autónoma de Madrid , Madrid , Spain
| | - Mercedes Perusquía
- b Instituto de Investigaciones Biomédicas, Departamento de Biología Celular y Fisiología , Universidad Nacional Autónoma de México , Mexico City , Mexico
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Boese AC, Chang L, Yin KJ, Chen YE, Lee JP, Hamblin MH. Sex differences in abdominal aortic aneurysms. Am J Physiol Heart Circ Physiol 2018; 314:H1137-H1152. [PMID: 29350999 DOI: 10.1152/ajpheart.00519.2017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Abdominal aortic aneurysm (AAA) is a vascular disorder with a high case fatality rate in the instance of rupture. AAA is a multifactorial disease, and the etiology is still not fully understood. AAA is more likely to occur in men, but women have a greater risk of rupture and worse prognosis. Women are reportedly protected against AAA possibly by premenopausal levels of estrogen and are, on average, diagnosed at older ages than men. Here, we review the present body of research on AAA pathophysiology in humans, animal models, and cultured cells, with an emphasis on sex differences and sex steroid hormone signaling.
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Affiliation(s)
- Austin C Boese
- Department of Pharmacology, Tulane University School of Medicine , New Orleans, Louisiana
| | - Lin Chang
- Center for Advanced Models for Translational Sciences and Therapeutics, Department of Internal Medicine, University of Michigan , Ann Arbor, Michigan
| | - Ke-Jie Yin
- Department of Neurology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Y Eugene Chen
- Center for Advanced Models for Translational Sciences and Therapeutics, Department of Internal Medicine, University of Michigan , Ann Arbor, Michigan
| | - Jean-Pyo Lee
- Department of Physiology, Tulane University School of Medicine , New Orleans, Louisiana.,Center for Stem Cell Research and Regenerative Medicine , New Orleans, Louisiana
| | - Milton H Hamblin
- Department of Pharmacology, Tulane University School of Medicine , New Orleans, Louisiana
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Villalpando DM, Rojas MM, García HS, Ferrer M. Dietary docosahexaenoic acid supplementation prevents the formation of cholesterol oxidation products in arteries from orchidectomized rats. PLoS One 2017; 12:e0185805. [PMID: 28968462 PMCID: PMC5624632 DOI: 10.1371/journal.pone.0185805] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 09/19/2017] [Indexed: 12/29/2022] Open
Abstract
Testosterone deficiency has been correlated with increased cardiovascular diseases, which in turn has been associated with increased oxidative stress. Several studies have considered cholesterol oxidation products (COPs) as oxidative stress biomarkers, since some of them play pro-oxidant and pro-inflammatory roles. We have previously described the cardioprotective effects of a dosahexaenoic acid (DHA) supplemented diet on the aortic and mesenteric artery function of orchidectomized rats. The aim of this study was to investigate whether impaired gonadal function alters the formation of COPs, as well as the potential preventive role of a DHA-supplemented diet on that effect. For this purpose, aortic and mesenteric artery segments obtained from control and orchidectomized rats, fed with a standard or supplemented with DHA, were used. The content of the following COPs: 7α-hydroxycholesterol, 7β-hydroxycholesterol, 7-ketocholesterol, 5,6α-epoxycholesterol, 5,6β-epoxycholesterol, cholestanetriol and 25-hydroxycholesterol, were analyzed by gas chromatography. The results showed that orchidectomy increased the formation of COPs in arteries from orchidectomized rats, which may participate in the orchidectomy-induced structural and functional vascular alterations already reported. The fact that the DHA-supplemented diet prevented the orchidectomy-induced COPs increase confirms the cardiovascular protective actions of DHA, which could be of special relevance in mesenteric arterial bed, since it importantly controls the systemic vascular resistance.
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Affiliation(s)
- Diva M. Villalpando
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Mibsam M. Rojas
- Unidad de Investigación y Desarrollo de Alimentos, Instituto Tecnológico de Veracruz, Veracruz, México
| | - Hugo S. García
- Unidad de Investigación y Desarrollo de Alimentos, Instituto Tecnológico de Veracruz, Veracruz, México
- * E-mail: (MF); (HSG)
| | - Mercedes Ferrer
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- * E-mail: (MF); (HSG)
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Villalpando DM, Navarro R, Del Campo L, Largo C, Muñoz D, Tabernero M, Baeza R, Otero C, García HS, Ferrer M. Docosahexaenoic Acid Supplemented Diet Influences the Orchidectomy-Induced Vascular Dysfunction in Rat Mesenteric Arteries. PLoS One 2017; 12:e0168841. [PMID: 28068359 PMCID: PMC5222371 DOI: 10.1371/journal.pone.0168841] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 11/02/2016] [Indexed: 01/29/2023] Open
Abstract
Over the past few decades, the cardiovascular benefits of a high dietary intake of long-chain polyunsaturated fatty acids (PUFAs), like docosahexaenoic acid (DHA), have been extensively studied. However, many of the molecular mechanisms and effects exerted by PUFAs have yet to be well explained. The lack of sex hormones alters vascular tone, and we have described that a DHA-supplemented diet to orchidectomized rats improve vascular function of the aorta. Based on these data and since the mesenteric artery importantly controls the systemic vascular resistance, the objective of this study was to analyze the effect of a DHA-supplemented diet on the mesenteric vascular function from orchidectomized rats. For this purpose mesenteric artery segments obtained from control, orchidectomized or orchidectomized plus DHA-supplemented diet were utilized to analyze: (1) the release of prostanoids, (2) formation of NO and ROS, (3) the vasodilator response to acetylcholine (ACh), as well as the involvement of prostanoids and NO in this response, and (4) the vasoconstrictor response to electrical field stimulation (EFS), analyzing also the effect of exogenous noradrenaline (NA), and the NO donor, sodium nitroprusside (SNP). The results demonstrate beneficial effects of DHA on the vascular function in orchidectomized rats, which include a decrease in the prostanoids release and superoxide formation that were previously augmented by orchidectomy. Additionally, there was an increase in endothelial NO formation and the response to ACh, in which NO involvement and the participation of vasodilator prostanoids were increased. DHA also reversed the decrease in EFS-induced response caused by orchidectomy. All of these findings suggest beneficial effects of DHA on vascular function by reversing the neurogenic response and the endothelial dysfunction caused by orchidectomy.
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Affiliation(s)
- Diva M Villalpando
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Área Cardiovascular, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain
| | - Rocío Navarro
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Lara Del Campo
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Área Cardiovascular, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain
| | - Carlota Largo
- Cirugía Experimental, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain
| | - David Muñoz
- Gabinete Veterinario, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - María Tabernero
- Cirugía Experimental, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain
| | - Ramiro Baeza
- Instituto de Catálisis y Petroleoquímica, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Cristina Otero
- Instituto de Catálisis y Petroleoquímica, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | | | - Mercedes Ferrer
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Área Cardiovascular, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ) Madrid, Spain
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Villalpando DM, Navarro R, del Campo L, Largo C, Muñoz D, Tabernero M, Baeza R, Otero C, García HS, Ferrer M. Effect of Dietary Docosahexaenoic Acid Supplementation on the Participation of Vasodilator Factors in Aorta from Orchidectomized Rats. PLoS One 2015; 10:e0142039. [PMID: 26540339 PMCID: PMC4634962 DOI: 10.1371/journal.pone.0142039] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 10/17/2015] [Indexed: 01/02/2023] Open
Abstract
Benefits of n-3 polyunsaturated fatty acids (PUFAs) against cardiovascular diseases have been reported. Vascular tone regulation is largely mediated by endothelial factors whose release is modulated by sex hormones. Since the incidence of cardiovascular pathologies has been correlated with decreased levels of sex hormones, the aim of this study was to analyze whether a diet supplemented with the specific PUFA docosahexaenoic acid (DHA) could prevent vascular changes induced by an impaired gonadal function. For this purpose, control and orchidectomized rats were fed with a standard diet supplemented with 5% (w/w) sunflower oil or with 3% (w/w) sunflower oil plus 2% (w/w) DHA. The lipid profile, the blood pressure, the production of prostanoids and nitric oxide (NO), and the redox status of biological samples from control and orchidectomized rats, fed control or DHA-supplemented diet, were analyzed. The vasodilator response and the contribution of NO, prostanoids and hyperpolarizing mechanisms were also studied. The results showed that orchidectomy negatively affected the lipid profile, increased the production of prostanoids and reactive oxygen species (ROS), and decreased NO production and the antioxidant capacity, as well as the participation of hyperpolarizing mechanisms in the vasodilator responses. The DHA-supplemented diet of the orchidectomized rats decreased the release of prostanoids and ROS, while increasing NO production and the antioxidant capacity, and it also improved the lipid profile. Additionally, it restored the participation of hyperpolarizing mechanisms by activating potassium. Since the modifications induced by the DHA-supplemented diet were observed in the orchidectomized, but not in the healthy group, DHA seems to exert cardioprotective effects in physiopathological situations in which vascular dysfunction exists.
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Affiliation(s)
- Diva M. Villalpando
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Área Cardiovascular, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
| | - Rocío Navarro
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Área Cardiovascular, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
| | - Lara del Campo
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Área Cardiovascular, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
| | - Carlota Largo
- Cirugía Experimental, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
| | - David Muñoz
- Gabinete Veterinario, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - María Tabernero
- Cirugía Experimental, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
| | - Ramiro Baeza
- Instituto de Catálisis y Petroleoquímica, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Cristina Otero
- Instituto de Catálisis y Petroleoquímica, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | | | - Mercedes Ferrer
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Área Cardiovascular, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
- * E-mail:
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Tostes RC, Carneiro FS, Carvalho MHC, Reckelhoff JF. Reactive oxygen species: players in the cardiovascular effects of testosterone. Am J Physiol Regul Integr Comp Physiol 2015; 310:R1-14. [PMID: 26538238 DOI: 10.1152/ajpregu.00392.2014] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 10/23/2015] [Indexed: 01/12/2023]
Abstract
Androgens are essential for the development and maintenance of male reproductive tissues and sexual function and for overall health and well being. Testosterone, the predominant and most important androgen, not only affects the male reproductive system, but also influences the activity of many other organs. In the cardiovascular system, the actions of testosterone are still controversial, its effects ranging from protective to deleterious. While early studies showed that testosterone replacement therapy exerted beneficial effects on cardiovascular disease, some recent safety studies point to a positive association between endogenous and supraphysiological levels of androgens/testosterone and cardiovascular disease risk. Among the possible mechanisms involved in the actions of testosterone on the cardiovascular system, indirect actions (changes in the lipid profile, insulin sensitivity, and hemostatic mechanisms, modulation of the sympathetic nervous system and renin-angiotensin-aldosterone system), as well as direct actions (modulatory effects on proinflammatory enzymes, on the generation of reactive oxygen species, nitric oxide bioavailability, and on vasoconstrictor signaling pathways) have been reported. This mini-review focuses on evidence indicating that testosterone has prooxidative actions that may contribute to its deleterious actions in the cardiovascular system. The controversial effects of testosterone on ROS generation and oxidant status, both prooxidant and antioxidant, in the cardiovascular system and in cells and tissues of other systems are reviewed.
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Affiliation(s)
- Rita C Tostes
- University of São Paulo, Ribeirao Preto Medical School, Ribeirao Preto, São Paulo, Brazil;
| | - Fernando S Carneiro
- University of São Paulo, Ribeirao Preto Medical School, Ribeirao Preto, São Paulo, Brazil
| | | | - Jane F Reckelhoff
- University of Mississippi Medical Center, Women's Health Research Center, Jackson, Mississippi
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del Campo M, Sagredo A, del Campo L, Villalobo A, Ferrer M. Time-dependent effect of orchidectomy on vascular nitric oxide and thromboxane A2 release. Functional implications to control cell proliferation through activation of the epidermal growth factor receptor. PLoS One 2014; 9:e102523. [PMID: 25013941 PMCID: PMC4094513 DOI: 10.1371/journal.pone.0102523] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Accepted: 06/20/2014] [Indexed: 11/19/2022] Open
Abstract
This study analyzes whether the release of nitric oxide (NO) and thromboxane A2 (TXA2) depends on the time lapsed since gonadal function is lost, and their correlation with the proliferation of vascular smooth muscle cells (VSMC) mediated by the epidermal growth factor receptor (EGFR). For this purpose, aortic and mesenteric artery segments from control and 6-weeks or 5-months orchidectomized rats were used to measure NO and TXA2 release. The results showed that the basal and acetylcholine (ACh)-induced NO release were decreased 6 weeks post-orchidectomy both in aorta and mesenteric artery, but were recovered 5 months thereafter up to levels similar to those found in arteries from control rats. The basal and ACh-induced TXA2 release increased in aorta and mesenteric artery 6 weeks post-orchidectomy, and was maintained at high levels 5 months thereafter. Since we previously observed that orchidectomy, which decreased testosterone level, enlarged the muscular layer of mesenteric arteries, the effect of testosterone on VSMC proliferation was analyzed. The results showed that treatment of cultured VSMC with testosterone downregulated mitogenic signaling pathways initiated by the ligand-dependent activation of the EGFR. In contrast, the EGFR pathways were constitutively active in mesenteric arteries of long-term orchidectomized rats. Thus, the exposure of mesenteric arteries from control rats to epidermal growth factor (EGF) induced the activation of EGFR signaling pathways. However, the addition of EGF to arteries from orchidectomized rats failed to induce a further activation of these pathways. In conclusion, this study shows that the release of NO depends on the time lapsed since the gonadal function is lost, while the release of TXA2 is already increased after short periods post-orchidectomy. The alterations in these signaling molecules could contribute to the constitutive activation of the EGFR and its downstream signaling pathways after long period post-orchidectomy enhancing the proliferation of the vascular muscular layer.
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MESH Headings
- Acetylcholine/pharmacology
- Animals
- Aorta/drug effects
- Aorta/metabolism
- Cell Proliferation/drug effects
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Epidermal Growth Factor/pharmacology
- ErbB Receptors/agonists
- ErbB Receptors/genetics
- ErbB Receptors/metabolism
- Gene Expression Regulation
- Male
- Mesenteric Arteries/drug effects
- Mesenteric Arteries/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Nitric Oxide/biosynthesis
- Nitric Oxide/metabolism
- Orchiectomy
- Rats
- Rats, Sprague-Dawley
- Signal Transduction
- Testosterone/pharmacology
- Thromboxane A2/biosynthesis
- Thromboxane A2/metabolism
- Time Factors
- Tissue Culture Techniques
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Affiliation(s)
- Marta del Campo
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Ana Sagredo
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Lara del Campo
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Instituto de Investigaciones Sanitarias IdIPAZ, Hospital La Paz, Madrid, Spain
| | - Antonio Villalobo
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Mercedes Ferrer
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Instituto de Investigaciones Sanitarias IdIPAZ, Hospital La Paz, Madrid, Spain
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Testosterone and β-oestradiol prevent inward remodelling of rat small mesenteric arteries: role of NO and transglutaminase. Clin Sci (Lond) 2013; 124:719-28. [PMID: 23330684 DOI: 10.1042/cs20120700] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Increasing evidence shows that sex hormones exert a protective effect on the vasculature, especially in the regulation of the active vasomotor responses. However, whether sex hormones affect vascular remodelling is currently unclear. In the present study, we tested the hypothesis that testosterone in males and β-oestradiol in females prevent inward remodelling, possibly through inhibition of cross-linking activity induced by enzymes of the TG (transglutaminase) family. Small mesenteric arteries were isolated from male and female Wistar rats. Dose-dependent relaxation to testosterone and β-oestradiol was inhibited by the NO synthase inhibitor L-NAME (NG-nitro-L-arginine methyl ester), confirming that these hormones induce NO release. When arteries were cannulated, pressurized and kept in organ culture with ET-1 (endothelin-1) for 3 days we observed strong vasoconstriction and inward remodelling. Remodelling was significantly inhibited by testosterone in males, and by β-oestradiol in females. This preventive effect of sex hormones was not observed in the presence of L-NAME. Inward remodelling was also reduced by the inhibitor of TG L682.777, both in males and females. In arteries from female rats, ET-1 increased TG activity, and this effect was prevented by β-oestradiol. L-NAME induced a significant increase in TG activity in the presence of sex hormones in arteries from both genders. We conclude that testosterone and β-oestradiol prevent constriction-induced inward remodelling. Inward remodelling, both in males and females, depends on NO and TG activity. In females, inhibition of inward remodelling could be mediated by NO-mediated inhibition of TG activity.
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Vasudevan H, Lau S, Jiang J, McNeill JH. Effects of insulin resistance and testosterone on the participation of cyclooxygenase isoforms in vascular reactivity. J Exp Pharmacol 2010; 2:169-79. [PMID: 27186103 PMCID: PMC4863301 DOI: 10.2147/jep.s14989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Testosterone plays an important role in mediating hypertension and altered vascular reactivity associated with insulin resistance. In addition to other pathways, testosterone-dependent changes in aortic cyclooxygenase (COX-2) mRNA levels affect blood pressure following insulin resistance. However their effects on vascular tone are unclear. We studied the changes in contraction response to phenylephrine (PE) in the aorta and superior mesenteric artery (SMA) from intact and gonadectomized fructose-fed rats. Constriction response to PE was studied in tissues incubated with the COX-1 and COX-2-selective antagonists, SC-560 and NS-398, respectively, and indomethacin, in addition to assessing its role in endothelium-dependent relaxation. Finally changes in COX-2 protein expression and plasma thromboxane A2 (TXA2), a downstream vasoconstrictor metabolite of COX-2, were measured. In fructose-fed rats, castration prevented the increase in blood pressure but not insulin resistance. The involvement of COX-2 in mediating the alpha-adrenergic vasoconstriction was higher in intact rat aorta compared to COX-1, which was prevented by castration. However, in the SMA, COX-2 participation was dependent on testosterone alone. Fructose-induced attenuation of endothelial relaxation was restored by indomethacin, which suggests a pro-vasoconstrictor role for COX. Both diet and testosterone did not alter vascular COX-2 expression thus suggesting the involvement of downstream testosterone-dependent pathways. This is supported by increased plasma TXA2 in the castrated rats compared to intact rats. Isoform-specific actions of COX are tissue-selective in states of insulin resistance and involve potential testosterone-dependent downstream targets. Further studies are needed to investigate the role of androgens and insulin resistance in vascular arachidonic acid metabolism.
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Affiliation(s)
- Harish Vasudevan
- Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sally Lau
- Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jihong Jiang
- Pediatric Oncology, Children and Women's Hospital, Child and Family Research Institute, Vancouver, British Columbia, Canada
| | - John H McNeill
- Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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Simultaneous inhibition of TXA(2) and PGI(2) synthesis increases NO release in mesenteric resistance arteries from cirrhotic rats. Clin Sci (Lond) 2010; 119:283-92. [PMID: 20459396 DOI: 10.1042/cs20090536] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Our present study examines, in mesenteric resistance arteries, possible vasodilation alterations, and the role of NO and COX (cyclo-oxygenase) derivatives, in cirrhosis. The vasodilator response to acetylcholine was analysed in segments from control and cirrhotic rats. The effects of the non-specific COX inhibitor indomethacin, the specific COX-1 inhibitor SC-560 and the specific COX-2 inhibitor NS-398 were analysed in segments from both groups of rats. NO release was measured, and eNOS [endothelial NOS (NO synthase)], phospho-eNOS, iNOS (inducible NOS), COX-1 and COX-2 protein expression was also analysed. The effects of the TP receptor [TXA2 (thromboxane A(2)) receptor] antagonist SQ 29548, the TXA(2) synthesis inhibitor furegrelate, the PGI(2) (prostaglandin I(2)) synthesis inhibitor TCP (tranylcypromine) or TCP+furegrelate were only determined in segments from cirrhotic rats. The vasodilator response to acetylcholine was higher in segments from cirrhotic rats. Indomethacin, SC-560 and NS-398 did not modify the vasodilator response in control rats; however, indomethacin, NS-398 and TCP+furegrelate increased, whereas SC-560 did not modify and SQ 29548, furegrelate or TCP decreased, the vasodilator response to acetylcholine in cirrhotic rats. NO release was higher in cirrhotic rats. Furegrelate decreased, whereas TCP+furegrelate increased, the NO release in segments from cirrhotic rats. eNOS and COX-1 protein expression was not modified, whereas phosho-eNOS, iNOS and COX-2 protein expression was higher in cirrhotic rats. Therefore the increase in iNOS expression and eNOS activity may mediate increases in endothelial NO release. The COX-2 derivatives TXA(2) and PGI(2) may act simultaneously, producing a compensatory effect that reduces NO release and may limit the hyperdynamic circulation.
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de Souza Rossignoli P, Pereira OCM, Chies AB. Orchidectomy enhances the effects of phenylephrine in rat isolated portal vein. Clin Exp Pharmacol Physiol 2009; 37:368-74. [PMID: 19843099 DOI: 10.1111/j.1440-1681.2009.05313.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
1. Orchidectomy results in long-term testosterone deprivation similar to that observed in male clinical pathologies, such as hypogonadism and age-related reductions in plasma testosterone concentrations. Although the vascular effects of these sorts of hormone deprivations are known in arteries, they have not been studied to the same extent in veins. 2. The aim of the present study was to determine the effect of orchidectomy, with or without subsequent testosterone replacement (started 23 days after orchidectomy; 10 mg/kg, i.m., testosterone propionate once every 5 days for 3 weeks), on responses of rat isolated portal veins and vena cavae to exogenous phenylephrine (PE). Isolated vessels were mounted in an organ bath and concentration-response curves constructed to PE (10(-10)-10(-4) mol/L), endothelin (ET; 10(-10)-10(-5) mol/L) and KCl (10(-2)-1.2 x 10(-1) mol/L; as a control). 3. Orchidectomy had no effect on contractile responses of either the portal vein or vena cava to KCl. However, orchidectomy enhanced the maximum response (R(max)) of the portal vein, but not the vena cava, to PE. Testosterone replacement had no effect on these responses. The effects of orchidectomy on the R(max) to PE in portal veins were not altered by the nitric oxide synthase inhibitor N(G)-nitro-l-arginine methyl ester (10(-4) mol/L) alone or combined with 10(-5) mol/L indomethacin (a non-selective cyclo-oxygenase inhibitor), but they were abolished following treatment of isolated vessels with the ET(A) and ET(B) receptor antagonists BQ-123 and BQ-788 (both at 10(-6) mol/L). Orchidectomy did not alter portal vein responses to the application of exogenous ET. 4. The results of the present study indicate that orchidectomy-induced decreases in plasma testosterone can increase the venoconstrictor effects of PE on the portal vein and that this effect involves activation of both ET(A) and ET(B) receptors by locally produced ET.
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Long-term portal hypertension increases the vasodilator response to acetylcholine in rat aorta: role of prostaglandin I2. Clin Sci (Lond) 2009; 117:365-74. [PMID: 19331646 DOI: 10.1042/cs20080499] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the present study, we have analysed both the effect of long-term portal hypertension on the vasomotor response to acetylcholine in rat aorta and the mechanism involved in this response. For this purpose, sham-operated rats and rats with pre-hepatic PH (portal hypertension; triple partial portal vein ligation) were used at 21 months after surgery. The participation of NO and COX (cyclo-oxygenase) derivatives in the vasodilator response elicited by acetylcholine after incubation with L-NAME (NG-nitro-L-arginine methyl ester), indomethacin, SC-560, NS-398, tranylcypromine and furegrelate, was analysed. NO, TXB2 (thromboxane B2) and 6-keto PGF1alpha (prostaglandin F1alpha) release were measured. In addition, SNP (sodium nitroprusside), U-46619, PGI2 and forskolin vasomotor responses were analysed. COX-1 and COX-2 expression was also determined. The acetylcholine-induced vasodilating response was higher in rats with PH. TXA2 and NO release, and SNP and U-46619 sensitivity were similar in both groups. PGI2 release was not modified by portal hypertension, but vasodilator responses to this prostanoid and to forskolin were higher in rats with PH. COX-1 and COX-2 expression remained unmodified by surgery. In conclusion, increased vasodilation to acetylcholine is maintained in long-term PH. Although the participation of endothelial NO remained unmodified, the COX-2 derivative PGI2 does participate through an increased vasodilator response.
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Martorell A, Sagredo A, Aras-López R, Balfagón G, Ferrer M. Ovariectomy increases the formation of prostanoids and modulates their role in acetylcholine-induced relaxation and nitric oxide release in the rat aorta. Cardiovasc Res 2009; 84:300-8. [PMID: 19567483 DOI: 10.1093/cvr/cvp214] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
AIMS This study examines the effect of ovarian function on thromboxane A(2) (TXA(2)), prostaglandin (PG) I(2), PGF(2alpha), and PGE(2) release as well as the role of these substances in nitric oxide (NO) release and acetylcholine (ACh)-mediated relaxation. METHODS AND RESULTS Aortic segments from ovariectomized and control female Sprague-Dawley rats were used. Cyclooxygenase (COX-1 and COX-2) expression was studied. ACh-induced relaxation was analysed in the absence and presence of the COX-2 inhibitor NS-398, the TXA(2) synthesis inhibitor furegrelate, the PGI(2) synthesis inhibitor tranylcypromine (TCP), or the thromboxane-prostanoid receptor antagonist SQ-29548. TXA(2), PGI(2), PGF(2alpha), and PGE(2) release was measured, and the vasomotor effect of exogenous TXA(2), PGI(2,) PGF(2alpha), and PGE(2) was assessed. Basal and ACh-induced NO release in the absence and presence of NS-398, furegrelate, TCP, or TCP plus furegrelate was studied. Ovariectomy did not alter or increased COX-1 or COX-2 expression, respectively. NS-398 decreased, and furegrelate did not change, the ACh-induced relaxation in arteries from both groups. SQ29,548 decreased the ACh-induced relaxation only in aortas from ovariectomized rats. TCP decreased the ACh-induced relaxation in both groups, and furegrelate or SQ29,548 totally restored that response only in aortas from control rats. Ovariectomy increased the ACh-induced TXA(2), PGI(2), and PGE(2) release and the contractile responses induced by exogenous TXA(2), PGF(2alpha), or PGE(2), while it decreased the PGI(2)-induced vasodilator response. In aortas from control rats, NS-398 did not alter the ACh-induced NO release, and furegrelate, TCP, or TCP plus furegrelate increased that release. In arteries from ovariectomized rats, NS-398, furegrelate, TCP, or TCP plus furegrelate decreased the ACh-induced NO release. CONCLUSION Despite the prevalence of vasoconstrictor prostanoids derived from COX-2 in aortas from ovariectomized rats, the ACh-induced relaxation is maintained, probably as consequence of the positive regulation that prostanoids exert on eNOS activity.
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Affiliation(s)
- Aina Martorell
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, C/Arzobispo Morcillo 4, 28029 Madrid, Spain
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Testosterone deprivation by castration impairs expression of voltage-dependent potassium channels in rat aorta. Eur J Pharmacol 2008; 593:87-91. [DOI: 10.1016/j.ejphar.2008.07.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Revised: 06/26/2008] [Accepted: 07/09/2008] [Indexed: 11/21/2022]
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