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Cartland SP, Stanley CP, Bursill C, Passam F, Figtree GA, Patel S, Loa J, Golledge J, Robinson DA, Aitken SJ, Kavurma MM. Sex, Endothelial Cell Functions, and Peripheral Artery Disease. Int J Mol Sci 2023; 24:17439. [PMID: 38139267 PMCID: PMC10744086 DOI: 10.3390/ijms242417439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 12/08/2023] [Accepted: 12/10/2023] [Indexed: 12/24/2023] Open
Abstract
Peripheral artery disease (PAD) is caused by blocked arteries due to atherosclerosis and/or thrombosis which reduce blood flow to the lower limbs. It results in major morbidity, including ischemic limb, claudication, and amputation, with patients also suffering a heightened risk of heart attack, stroke, and death. Recent studies suggest women have a higher prevalence of PAD than men, and with worse outcomes after intervention. In addition to a potential unconscious bias faced by women with PAD in the health system, with underdiagnosis, and lower rates of guideline-based therapy, fundamental biological differences between men and women may be important. In this review, we highlight sexual dimorphisms in endothelial cell functions and how they may impact PAD pathophysiology in women. Understanding sex-specific mechanisms in PAD is essential for the development of new therapies and personalized care for patients with PAD.
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Affiliation(s)
- Siân P. Cartland
- Heart Research Institute, The University of Sydney, Sydney, NSW 2042, Australia; (S.P.C.); (C.P.S.); (S.P.)
| | - Christopher P. Stanley
- Heart Research Institute, The University of Sydney, Sydney, NSW 2042, Australia; (S.P.C.); (C.P.S.); (S.P.)
| | - Christina Bursill
- South Australian Health and Medical Research Institute, Adelaide, SA 5000, Australia;
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
| | - Freda Passam
- Faculty of Health and Medicine, The University of Sydney, Sydney, NSW 2050, Australia; (F.P.); (G.A.F.); (S.J.A.)
| | - Gemma A. Figtree
- Faculty of Health and Medicine, The University of Sydney, Sydney, NSW 2050, Australia; (F.P.); (G.A.F.); (S.J.A.)
- Kolling Institute of Medical Research, Sydney, NSW 2064, Australia
| | - Sanjay Patel
- Heart Research Institute, The University of Sydney, Sydney, NSW 2042, Australia; (S.P.C.); (C.P.S.); (S.P.)
- Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia (D.A.R.)
| | - Jacky Loa
- Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia (D.A.R.)
| | - Jonathan Golledge
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia;
- Department of Vascular and Endovascular Surgery, The Townsville University Hospital, Townsville, QLD 4814, Australia
| | | | - Sarah J. Aitken
- Faculty of Health and Medicine, The University of Sydney, Sydney, NSW 2050, Australia; (F.P.); (G.A.F.); (S.J.A.)
- Concord Institute of Academic Surgery, Concord Repatriation General Hospital, Sydney, NSW 2139, Australia
| | - Mary M. Kavurma
- Heart Research Institute, The University of Sydney, Sydney, NSW 2042, Australia; (S.P.C.); (C.P.S.); (S.P.)
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Kim S, Chaudhary PK, Kim S. Role of Prednisolone in Platelet Activation by Inhibiting TxA 2 Generation through the Regulation of cPLA 2 Phosphorylation. Animals (Basel) 2023; 13:ani13081299. [PMID: 37106862 PMCID: PMC10135208 DOI: 10.3390/ani13081299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 04/03/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
Glucocorticoids have been commonly used in the treatment of inflammation and immune-mediated diseases in human beings and small animals such as cats and dogs. However, excessive use can lead to Cushing's syndrome along with several thrombotic and cardiovascular diseases. Although it is well-known that glucocorticoids exert a significant effect on coagulation, the effect of cortisol on platelet function is much less clear. Thus, we aimed to study the effects of prednisolone, one of the commonly used glucocorticoids, on the regulation of platelet function using murine platelets. We first evaluated the concentration-dependent effect of prednisolone on 2-MeSADP-induced platelet function and found that the 2-MeSADP-induced secondary wave of aggregation and dense granule secretion were completely inhibited from 500 nM prednisolone. Since 2-MeSADP-induced secretion and the resultant secondary wave of aggregation are mediated by TxA2 generation, this result suggested a role of prednisolone in platelet TxA2 generation. Consistently, prednisolone did not affect the 2-MeSADP-induced aggregation in aspirinated platelets, where the secondary wave of aggregation and secretion were blocked by eliminating the contribution of TxA2 generation by aspirin. In addition, thrombin-induced platelet aggregation and secretion were inhibited in the presence of prednisolone by inhibiting the positive-feedback effect of TxA2 generation on platelet function. Furthermore, prednisolone completely inhibited 2-MeSADP-induced TxA2 generation, confirming the role of prednisolone in TxA2 generation. Finally, Western blot analysis revealed that prednisolone significantly inhibited 2-MeSADP-induced cytosolic phospholipase A2 (cPLA2) and ERK phosphorylation in non-aspirinated platelets, while only cPLA2 phosphorylation, but not ERK phosphorylation, was significantly inhibited by prednisolone in aspirinated platelets. In conclusion, prednisolone affects platelet function by the inhibition of TxA2 generation through the regulation of cPLA2 phosphorylation, thereby shedding light on its clinical characterization and treatment efficacy in dogs with hypercortisolism in the future.
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Affiliation(s)
- Sanggu Kim
- Laboratory of Veterinary Pathology and Platelet Signaling, College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Preeti Kumari Chaudhary
- Laboratory of Veterinary Pathology and Platelet Signaling, College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Soochong Kim
- Laboratory of Veterinary Pathology and Platelet Signaling, College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea
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Chang S, Larsen OH, Hvas AM, Skakkebaek A, Gravholt CH, Münster AMB. Platelet aggregation in Klinefelter syndrome is not aggravated by testosterone replacement therapy: A longitudinal follow-up study. Andrology 2023; 11:456-463. [PMID: 36300871 DOI: 10.1111/andr.13330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 10/14/2022] [Accepted: 10/21/2022] [Indexed: 11/27/2022]
Abstract
BACKGROUND Men with Klinefelter syndrome (KS) are routinely offered testosterone replacement therapy (TRT) suggested to potentially promote platelet aggregation and increase cardiovascular risk. OBJECTIVE We investigated platelet aggregation in men with KS before and during TRT. MATERIALS AND METHODS Forty-one adult men with KS participated, of which 20 had no history of TRT at baseline, with 15 completing follow-up after 18 months TRT. Further, we included 21 adult men with KS on long-term TRT (>10 years) and a male reference population. We assessed platelet impedance aggregometry using adenosine diphosphate (6.5 μM), thrombin-receptor-activating-peptide-6 (TRAP 32 μM), and arachidonic acid (ASPI 0.5 mM) as agonists in KS compared to a male reference population and stratified by route of TRT administration. RESULTS Platelet aggregation among men with KS at baseline or during TRT was not increased compared with the male reference population. For all three agonist, no change was seen in platelet aggregation in KS at follow-up compared with baseline (p ≥ 0.2). Platelet aggregation was not associated with total testosterone and furthermore, platelet count was not affected by treatment with testosterone. Men with KS treated with testosterone gel showed slightly increased TRAP- and ASPI-induced platelet aggregation compared with those treated with testosterone injection (p = 0.02 and p = 0.04, respectively). DISCUSSION AND CONCLUSIONS We observed normal platelet aggregation in men with KS before TRT and following both short and long term treatment. Our findings do not support an independent role of platelets in driving the cardiovascular risk in KS.
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Affiliation(s)
- Simon Chang
- Unit for Thrombosis Research, University of Southern Denmark, Esbjerg, Denmark.,Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Ole Halfdan Larsen
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Anne-Mette Hvas
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Anne Skakkebaek
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Claus Højbjerg Gravholt
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
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Sobral MLP, Dias RR, Correia CDJ, Coutinho E Silva RDS, da Anunciação LF, Breithaupt-Faloppa AC, Moreira LFP. Protective effects of 17β-oestradiol on coagulation and systemic inflammation after total occlusion of the descending aorta in male rats. Eur J Cardiothorac Surg 2021; 61:666-674. [PMID: 34528682 DOI: 10.1093/ejcts/ezab381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/14/2021] [Accepted: 07/04/2021] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVES The surgical treatment for diseases of the descending aorta is related to a high mortality rate because of the activation of a systemic inflammatory process due to ischaemia and reperfusion (I/R) injury. Activation of coagulation can contribute to the inflammatory process, resulting in microcirculatory damage and multiple organ failure. Our goal was to evaluate the role of prophylactic intravenous 17β-oestradiol (E2) in coagulation, the inflammatory response and hepatic injury after occlusion of the descendent proximal aorta in male rats. METHODS Wistar male rats were randomized and allocated to 3 groups (n = 8 per group): sham, surgically manipulated; IR, animals subjected to I/R; and E2, animals treated with E2 (280 µg/kg, intravenously) before I/R. I/R was induced by insertion of a 2-Fr Fogarty arterial embolectomy catheter in the descending aorta, which was occluded for 20 min, followed by a reperfusion period of 2 h. Serological markers, platelet aggregation, hepatic vascular flow, systemic and liver inflammatory response and apoptosis were analysed. The coagulation process was evaluated by thromboelastometry. RESULTS The aortic occlusion led to a reduction in plasma fibrinogen concentration in parallel with increased clotting time, greater clot firmness and reduced lysis. E2 treatment was able to increase fibrinogen, prevent the increase in clotting time and normalize clot firmness, but it exerted only a mild effect on clot lysis. Platelet aggregation was increased by IR, and E2 treatment was able to reduce it. There was a reduction in flow percentage in the IR group that was not prevented by E2. In parallel, higher aggregate formation was observed in the vessels of the IR group of animals. There was increased systemic release of interleukin-1-β, interleukin-6 and interleukin-10 in the IR group, which was reduced in the treated animals. CONCLUSIONS The current results suggest that pretreatment with E2 before an ischaemic period induced by occlusion of the proximal descending aorta is effective in preventing alterations in coagulation and systemic inflammation due to I/R injury.
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Affiliation(s)
- Marcelo Luiz Peixoto Sobral
- Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação (LIM-11), Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Ricardo Ribeiro Dias
- Department of Cardiovascular Surgery, Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Cristiano de Jesus Correia
- Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação (LIM-11), Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Raphael Dos Santos Coutinho E Silva
- Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação (LIM-11), Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Lucas Ferreira da Anunciação
- Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação (LIM-11), Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Ana Cristina Breithaupt-Faloppa
- Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação (LIM-11), Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Luiz Felipe Pinho Moreira
- Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação (LIM-11), Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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Abstract
Aim: This article reviews the possibility of using combined hormonal contraception during the COVID-19 pandemic. Methods: narrative reviewResults: The factors that protect women from the severity of the disease are analysed, as well as the risk factors for the use of this type of contraception, especially related to the increased risk of a thrombotic event in patients affected by the disease. Finally, the information available on the guidelines for action in patients with COVID-19 using combined hormonal contraception is collected.Conclusions: We can continue to prescribe and use hormonal methods with EE.
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Affiliation(s)
- Iñaki Lete
- Obstetrics and Gynecology Clinical Management Unit, Araba University Hospital, Vitoria, Spain
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Platelet Responses in Cardiovascular Disease: Sex-Related Differences in Nutritional and Pharmacological Interventions. Cardiovasc Ther 2020; 2020:2342837. [PMID: 32547635 PMCID: PMC7273457 DOI: 10.1155/2020/2342837] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/09/2020] [Indexed: 12/12/2022] Open
Abstract
Cardiovascular diseases (CVD) represent one of the biggest causes of death globally, and their prevalence, aetiology, and outcome are related to genetic, metabolic, and environmental factors, among which sex- and age-dependent differences may play a key role. Among CVD risk factors, platelet hyperactivity deserves particular mention, as it is involved in the pathophysiology of main cardiovascular events (including stroke, myocardial infarction, and peripheral vascular injury) and is closely related to sex/age differences. Several determinants (e.g., hormonal status and traditional cardiovascular risk factors), together with platelet-related factors (e.g., plasma membrane composition, receptor signaling, and platelet-derived microparticles) can elucidate sex-related disparity in platelet functionality and CVD onset and outcome, especially in relation to efficacy of current primary and secondary interventional strategies. Here, we examined the state of the art concerning sex differences in platelet biology and their relationship with specific cardiovascular events and responses to common antiplatelet therapies. Moreover, as healthy nutrition is widely recognized to play a key role in CVD, we also focused our attention on specific dietary components (especially polyunsaturated fatty acids and flavonoids) and patterns (such as Mediterranean diet), which also emerged to impact platelet functions in a sex-dependent manner. These results highlight that full understanding of gender-related differences will be useful for designing personalized strategies, in order to prevent and/or treat platelet-mediated vascular damage.
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Breithaupt-Faloppa AC, Correia CDJ, Prado CM, Stilhano RS, Ureshino RP, Moreira LFP. 17β-Estradiol, a potential ally to alleviate SARS-CoV-2 infection. Clinics (Sao Paulo) 2020; 75:e1980. [PMID: 32490931 PMCID: PMC7233687 DOI: 10.6061/clinics/2020/e1980] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 05/05/2020] [Indexed: 01/08/2023] Open
Abstract
Considering that female sexual hormones may modulate the inflammatory response and also exhibit direct effects on the cells of the immune system, herein, we intend to discuss the sex differences and the role of estradiol in modulating the lung and systemic inflammatory response, focusing on its possible application as a treatment modality for SARS-CoV-2 patients. COVID-19 patients develop severe hypoxemia early in the course of the disease, which is silent most of the time. Small fibrinous thrombi in pulmonary arterioles and a tumefaction of endothelial were observed in the autopsies of fatal COVID-19 cases. Studies showed that the viral infection induces a vascular process in the lung, which included vasodilation and endothelial dysfunction. Further, the proportions of CD4+ T and CD8+ T lymphocytes were strongly reduced in patients with severe SARS-CoV-2 infection. Estradiol is connected with CD4+ T cell numbers and increases T-reg cell populations, affecting immune responses to infection. It is known that estradiol exerts a protective effect on endothelial function, activating the generation of nitric oxide (NO) via endothelial nitric oxide synthase. Estrogen attenuates the vasoconstrictor response to various stimuli and induces vasodilation in the pulmonary vasculature during stress situations like hypoxia. It exerts a variety of rapid actions, which are initiated after its coupling with membrane receptors, which in turn, may positively modulate vascular responses in pulmonary disease and help to maintain microvascular flow. Direct and indirect mechanisms underlying the effects of estradiol were investigated, and the results point to a possible protective effect of estradiol against COVID-19, indicating that it may be considered as an adjuvant therapeutic element for the treatment of patients affected by the novel coronavirus.
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Affiliation(s)
- Ana Cristina Breithaupt-Faloppa
- Laboratorio de Cirurgia Cardiovascular e Fisiopatologia da Circulacao (LIM-11), Instituto do Coracao (InCor), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR
- *Corresponding author. E-mail:
| | - Cristiano de Jesus Correia
- Laboratorio de Cirurgia Cardiovascular e Fisiopatologia da Circulacao (LIM-11), Instituto do Coracao (InCor), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR
| | - Carla Máximo Prado
- Instituto de Saude e Sociedade (ISS), Universidade Federal de Sao Paulo (UNIFESP), Santos, SP, BR
| | | | - Rodrigo Portes Ureshino
- Departamento de Ciencias Biologicas, Universidade Federal de Sao Paulo (UNIFESP), Diadema, SP, BR
- Laboratorio de Endocrinologia Molecular e Translacional, Escola Paulista de Medicina, Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP, BR
| | - Luiz Felipe Pinho Moreira
- Laboratorio de Cirurgia Cardiovascular e Fisiopatologia da Circulacao (LIM-11), Instituto do Coracao (InCor), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR
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Jayakumar T, Yang CH, Geraldine P, Yen TL, Sheu JR. The pharmacodynamics of antiplatelet compounds in thrombosis treatment. Expert Opin Drug Metab Toxicol 2016; 12:615-32. [DOI: 10.1080/17425255.2016.1176141] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Thanasekaran Jayakumar
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan
- Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chih-Hao Yang
- Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Pitchairaj Geraldine
- Department of Animal Science, School of Life Sciences, Bharathidasan University, Tiruchirappalli, India
| | - Ting-Lin Yen
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan
| | - Joen-Rong Sheu
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan
- Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- College of Medicine, Taipei Medical University, Taipei, Taiwan
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Sun D, Wu Y, Yuan Y, Wang Y, Liu W, Yang J. Is the atherosclerotic process accentuated under conditions of HIV infection, antiretroviral therapy, and protease inhibitor exposure? Meta-analysis of the markers of arterial structure and function. Atherosclerosis 2015; 242:109-16. [PMID: 26188532 DOI: 10.1016/j.atherosclerosis.2015.06.059] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 03/17/2015] [Accepted: 06/30/2015] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To evaluate the apparent association of human immunodeficiency virus (HIV) infection, antiretroviral therapy (ART), and protease inhibitor (PI) exposure with the functional and structural markers of vasculature. METHODS A meta-analysis of the relationship between HIV infection, ART, and PI exposure and the functional and structural markers of vasculature. A systematic literature search was performed electronically using specific eligibility criteria. Weighted mean difference (WMD) and corresponding 95% confidence interval (CI) were calculated and combined appropriately. RESULTS Fifty-seven articles were included with nine different outcomes. Compared with HIV-negative patients, HIV-positive patients demonstrated significant elevated intima-media thickness (IMT) (WMD (95% CI) = 0.042 (0.028-0.057)), increased pulse wave velocity (PWV) (0.538 (0.283-0.792)), and reduced flow-mediated vasodilation (FMD) (-2.049 (-2.806 to -1.293)). Elevated IMT was observed in HIV patients receiving ART when compared with those naïve to ART in the 20- to 40-year-old age group (0.078 (0.033-0.123)), the >40-year-old age group (0.038 (0.018-0.057)), and the group comprising >50% males (0.070 (0.041-0.099)). In addition, ART resulted in an increased PWV in HIV patients receiving ART in the group with >50% male proportion (0.628 (0.405-0.851)). HIV patients exposed to PI showed a significant trend toward elevated IMT (0.033 (0.007-0.058)) and increased PWV (0.264 (0.118-0.410)) compared with those without PI exposure. CONCLUSIONS The atherosclerotic process was accentuated by elevated IMT, increased PWV, and reduced FMD under condition of HIV infection. Comparison of ART-receiving with ART-naïve patients showed a significant trend toward elevated IMT and increased PWV, especially under treatment with PI-containing drugs.
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Affiliation(s)
- Dandan Sun
- Department of Cardiovascular Ultrasound, The First Affiliated Hospital of China Medical University, Liaoning Province, Shenyang 110001, China
| | - Yupeng Wu
- Department of Neurosurgery, The First Affiliated Hospital of China Medical University, Liaoning Province, Shenyang 110001, China
| | - Yuan Yuan
- Department of Tumor Etiology and Screening, Cancer Institute and General Surgery, The First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention, Liaoning Provincial Education Department, Shenyang 110001, China
| | - Yun Wang
- Department of Cardiovascular Ultrasound, The First Affiliated Hospital of China Medical University, Liaoning Province, Shenyang 110001, China
| | - Wen Liu
- Department of Cardiovascular Ultrasound, The First Affiliated Hospital of China Medical University, Liaoning Province, Shenyang 110001, China
| | - Jun Yang
- Department of Cardiovascular Ultrasound, The First Affiliated Hospital of China Medical University, Liaoning Province, Shenyang 110001, China.
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Mury WV, Brunini TMC, Abrantes DC, Mendes IKS, Campos MBGB, Mendes-Ribeiro AC, Matsuura C. Hyperaggregability and impaired nitric oxide production in platelets from postmenopausal women. Maturitas 2014; 80:75-81. [PMID: 25456263 DOI: 10.1016/j.maturitas.2014.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/29/2014] [Accepted: 10/02/2014] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Cardiovascular mortality increases after menopause in women. Nitric oxide is essential for proper platelet function inhibiting its aggregation and maintaining vascular haemostasis. Here, we investigated whether platelet function and intraplatelet l-arginine-nitric oxide pathway are impaired in postmenopausal women. STUDY DESIGN Cross-sectional. MAIN OUTCOMES MEASURES Blood was collected from 16 premenopausal and 12 postmenopausal women without any additional risk factor for cardiovascular disease. Platelet reactivity was measured by light transmission aggregometry. l-Arginine-nitric oxide pathway was assessed measuring transmembrane l-[(3)H]-arginine transport, nitric oxide synthase activity by the citrulline assay, and arginase activity by the conversion of l-[(14)C]arginine to l-[(14)C]-urea. The activity of antioxidant enzymes was measured by spectrophotometric assays. Protein expression was determined by Western blotting. RESULTS Platelet aggregation was increased in postmenopausal compared to premenopausal women. Postmenopausal women demonstrated reduced plasma levels of l-arginine, a lower nitric oxide synthase activity, similar endothelial and inducible nitric oxide synthase expression, and a compensatory increase in l-arginine transmembrane transport. Arginase expression and activity did not differ between groups. In regard to oxidative stress, no differences between groups were observed NAPDH oxidase subunits expression and protein carbonylation. However, the activity of the antioxidant enzyme superoxide dismutase and catalase protein levels in platelets were higher in postmenopausal women. CONCLUSION Postmenopausal women present increased platelet reactivity, which may be due to a reduction in intraplatelet nitric oxide synthesis. Platelet hyperaggregability is known to be associated with arterial and venous thromboembolic event; therefore, it may contribute to the heightened risk of cardiovascular adverse events in this population.
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Affiliation(s)
- Wanda V Mury
- Departament of Pharmacolgy and Psychobiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Tatiana M C Brunini
- Departament of Pharmacolgy and Psychobiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Daniele C Abrantes
- Departament of Pharmacolgy and Psychobiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Iara K S Mendes
- Departament of Pharmacolgy and Psychobiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Maria B G B Campos
- Departament of Gynaecology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Antônio C Mendes-Ribeiro
- Departament of Pharmacolgy and Psychobiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil; Departament of Physiological Sciences, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Cristiane Matsuura
- Departament of Pharmacolgy and Psychobiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
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Zeng C, Yang F, He H, Hu K, Wang X, Hu Q, Li J. Raloxifene hydrochloride treatment leads to better outcomes than medroxyprogesterone acetate when paired with estrogen in ovariectomized cholesterol-fed rabbits. Acta Biochim Biophys Sin (Shanghai) 2014; 46:1080-3. [PMID: 25348734 DOI: 10.1093/abbs/gmu098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Caiyu Zeng
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Qilu Hospital, Shandong University, Jinan 250012, China Department of Cardiology, Qilu Hospital, Shandong University, Jinan 250012, China
| | - Falin Yang
- Clinical Laboratory, Qilu Hospital, Shandong University, Jinan 250012, China
| | - Hong He
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Qilu Hospital, Shandong University, Jinan 250012, China Department of Cardiology, Qilu Hospital, Shandong University, Jinan 250012, China
| | - Keqing Hu
- Department of Cardiology, Jinan Central Hospital Affiliated to Shandong University, Jinan 250012, China
| | - Xin Wang
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Qilu Hospital, Shandong University, Jinan 250012, China Department of Cardiology, Qilu Hospital, Shandong University, Jinan 250012, China
| | - Qin Hu
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Qilu Hospital, Shandong University, Jinan 250012, China Department of Cardiology, Qilu Hospital, Shandong University, Jinan 250012, China
| | - Jifu Li
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Qilu Hospital, Shandong University, Jinan 250012, China Department of Cardiology, Qilu Hospital, Shandong University, Jinan 250012, China
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Effects of an aqueous extract of dangguijagyagsan on serum lipid levels and blood flow improvement in ovariectomized rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:497836. [PMID: 25276217 PMCID: PMC4171084 DOI: 10.1155/2014/497836] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 08/12/2014] [Accepted: 08/12/2014] [Indexed: 01/14/2023]
Abstract
Dangguijagyagsan (DJS), a traditional herbal prescription, has long been used to treat menopause-related symptoms. We identified the cardioprotective effects of an aqueous extract of DJS using an ovariectomized (OVX) and ferric chloride- (FeCl-) induced carotid thrombosis rat model. Female Sprague-Dawley (SD) rats were ovariectomized or Sham-operated (Sham-control). The ovariectomized rats were divided into three groups: OVX with saline (OVX-control), aspirin 30 mg/kg/day (OVX-ASA), and DJS 100 mg/kg/day (OVX-DJS). The treatments were administered for 5 weeks. Then, blood samples were collected to analyze the serum lipid levels and platelet aggregation. The topical application of 40% FeCl3 induced intravascular thrombosis, which was used to test thrombotic occlusion and for histological examination. Body weight and the levels of total cholesterol (TC), triglyceride (TG), and LDL-cholesterol (LDL-C) increased in the OVX rats. These effects were reduced by ASA and DJS treatment. In addition, ASA and DJS treatment significantly inhibited platelet aggregation. These treatments also increased time to occlusion and decreased both thrombus size and the presence of collagen fibers in surrounding vessel walls compared with the Sham-control and OVX-control groups. These results suggest that DJS has beneficial effects in terms of preventing cardiovascular disease in menopausal woman because it can reduce the serum lipid levels and improve blood flow by inhibiting platelet aggregation and thrombus formation.
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Ritzel RM, Capozzi LA, McCullough LD. Sex, stroke, and inflammation: the potential for estrogen-mediated immunoprotection in stroke. Horm Behav 2013; 63:238-53. [PMID: 22561337 PMCID: PMC3426619 DOI: 10.1016/j.yhbeh.2012.04.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 04/13/2012] [Accepted: 04/14/2012] [Indexed: 01/05/2023]
Abstract
Stroke is the third leading cause of death and the primary cause of disability in the developed world. Experimental and clinical data indicate that stroke is a sexually dimorphic disease, with males demonstrating an enhanced intrinsic sensitivity to ischemic damage throughout most of their lifespan. The neuroprotective role of estrogen in the female brain is well established, however, estrogen exposure can also be deleterious, especially in older women. The mechanisms for this remain unclear. Our current understanding is based on studies examining estrogen as it relates to neuronal injury, yet cerebral ischemia also induces a robust sterile inflammatory response involving local and systemic immune cells. Despite the potent anti-inflammatory effects of estrogen, few studies have investigated the contribution of estrogen to sex differences in the inflammatory response to stroke. This review examines the potential role for estrogen-mediated immunoprotection in ischemic injury.
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Affiliation(s)
- Rodney M Ritzel
- University of Connecticut Health Center, Department of Neuroscience, Farmington, CT 06030, USA
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14
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GARRIDO A, MUÑOZ Y, SIERRALTA W, VALLADARES L. Metabolism of Dehydroepiandrosterone Sulfate and Estrone-Sulfate by Human Platelets. Physiol Res 2012; 61:381-8. [DOI: 10.33549/physiolres.932323] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The aim of the present research was to study the uptake of DHEAS, and to establish the intracrine capacity of human platelets to produce sex steroid hormones. The DHEAS transport was evaluated through the uptake of [3H]-DHEAS in the presence or absence of different substrates through the organic anion transporting polypeptide (OATP) family. The activity of sulfatase enzyme was evaluated, and the metabolism of DHEAS was measured by the conversion of [3H]-DHEAS to [3H]-androstenedione, [3H]-testosterone, [3H]-estrone and [3H]-17β-estradiol. Results indicated the existence in the plasma membrane of an OATP with high affinity for DHEAS and estrone sulphate (E1S). The platelets showed the capacity to convert DHEAS to active DHEA by the steroid-sulfatase activity. The cells resulted to be a potential site for androgens production, since they have the capacity to produce androstenedione and testosterone; in addition, they reduced [3H]-estrone to [3H]-17β-estradiol. This is the first demonstration that human platelets are able to import DHEAS and E1S using the OATP family and to convert DHEAS to active DHEA, and to transform E1S to 17β-estradiol.
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Affiliation(s)
| | | | | | - L. VALLADARES
- Institute of Nutrition and Food Technology, Universidad de Chile, Santiago, Chile
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15
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Borgdorff P, Tangelder GJ. Migraine: possible role of shear-induced platelet aggregation with serotonin release. Headache 2012; 52:1298-318. [PMID: 22568554 DOI: 10.1111/j.1526-4610.2012.02162.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Migraine patients are at an increased risk for stroke, as well as other thromboembolic events. This warrants further study of the role of platelets in a proportion of migraine patients. OBJECTIVE To extend the "platelet hypothesis" using literature data and observations made in a rat model of shear stress-induced platelet aggregation. Such aggregation causes release of serotonin, leading to vasoconstriction during sufficiently strong aggregation and to long-lasting vasodilation when aggregation diminishes. This vasodilation also depends on nitric oxide and prostaglandin formation. RESULTS A role for platelet aggregation in a number of migraineurs is indicated by reports of an increased platelet activity during attacks and favorable effects of antiplatelet medication. We hypothesize that in those patients, a migraine attack with or without aura may both be caused by a rise in platelet-released plasma serotonin, albeit at different concentration. At high concentrations, serotonin may cause vasoconstriction and, consequently, the neuronal signs of aura, whereas at low concentrations, it may already stimulate perivascular pain fibers and cause vasodilation via local formation of nitric oxide, prostaglandins, and neuropeptides. Platelet aggregation may be unilaterally evoked by elevated shear stress in a stenotic cervico-cranial artery, by reversible vasoconstriction or by other cardiovascular abnormality, eg, a symptomatic patent foramen ovale. This most likely occurs when a migraine trigger has further enhanced platelet aggregability; literature shows that many triggers either stimulate platelets directly or reduce endogenous platelet antagonists like prostacyclin. CONCLUSION New strategies for migraine medication and risk reduction of stroke are suggested.
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Affiliation(s)
- Piet Borgdorff
- Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
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16
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Chiba T, Ikeda M, Umegaki K, Tomita T. Estrogen-dependent activation of neutral cholesterol ester hydrolase underlying gender difference of atherogenesis in apoE-/- mice. Atherosclerosis 2011; 219:545-51. [PMID: 21944698 DOI: 10.1016/j.atherosclerosis.2011.08.051] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 08/31/2011] [Accepted: 08/31/2011] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Mechanisms underlying gender difference of atherogenesis were investigated focusing on direct effects of estrogen on the artery. METHODS First, male and female apoE(-/-) mice were fed an atherogenic diet for 16 weeks from 10 weeks of age. Second, female apoE(-/-) mice were ovariectomized (ovx) or sham operated at 8 weeks of age, and 2-weeks afterwards, one-third of each ovx-group received conjugated equine estrogens (CEE) (0, 2.5 or 5.0 μg/day) for 16 weeks. Atherosclerotic lesions were examined after experimental periods. To clarify anti-atherogenic effect of 17β-estradiol (E2) on artery, neutral cholesteryl ester hydrolase (N-CEase) activity in aorta and peritoneal macrophages, and E2-treated J774A.1 cells were measured. RESULTS First, atherosclerotic lesion in female mice was significantly less than male mice without any changes in serum lipids and lipoprotein profile. N-CEase activity in aorta and peritoneal macrophages in female mice was significantly higher than male mice. Second, atherosclerotic lesion in ovx-group was significantly greater than sham-group. CEE-replacement to ovx-group decreased atherosclerotic lesion in a dose-dependent manner. N-CEase activity in aorta and peritoneal macrophages was decreased in ovx-group compared to sham-group, and restored by CEE-replacement in macrophages. To study detailed mechanisms, J774A.1 cells were treated with E2. E2 significantly increased N-CEase activity, and cAMP-dependent protein kinase (A-kinase) type II activity and the protein in cytosol fraction without any changes of total protein of A-kinase type II. CONCLUSION These results suggest that gender difference of atherogenesis is partly accounted for activation of N-CEase through estrogen-dependent translocation of A-kinase type II in macrophages.
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Affiliation(s)
- Tsuyoshi Chiba
- Graduate School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka-shi, Shizuoka 422-8526, Japan.
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17
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Zamaraeva M, Charishnikova O, Saidkhodjaev A, Isidorov V, Granosik M, Różalski M, Watała C. Calcium mobilization by the plant estrogen ferutinin does not induce blood platelet aggregation. Pharmacol Rep 2011; 62:1117-26. [PMID: 21273669 DOI: 10.1016/s1734-1140(10)70374-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 03/01/2010] [Indexed: 10/25/2022]
Abstract
Platelet activation is closely associated with an increase in intracellular Ca(2+) concentration. Various compounds including Ca(2+) ionophores are able to trigger platelet aggregation by increasing intracellular Ca(2+) concentration in platelets. In the present study, we monitored the effect of the phytoestrogen ferutinin, which acts as a Ca(2+) ionophore in human blood platelets; its ionophore-like properties include upregulation of [Ca(2+)](in), activation of fibrinogen receptors and increased fibrinogen binding. Using spectrofluorometry and triple-color flow cytometry, we demonstrate that ferutinin increases [Ca(2+)](in) in both isolated platelets and platelets in whole blood from humans. This effect was almost completely blocked by the Ca(2+) chelator EGTA and was not sensitive to either Gd(3+) or econazole, which inhibit VOC and SOC channels, respectively. Nor was the effect sensitive to thapsigargin, an inhibitor of endoplasmic reticulum Ca(2+) ATPases. Ferutinin stimulated the expression of the active form of the GPIIb-IIIa complex and whole blood platelet aggregation only weakly and had no statistically significant effect on the binding of fibrinogen. These results demonstrate apparently inconsistent effects of ferutinin, which raises intraplatelet Ca(2+) concentration but fails to have an effect on spontaneous blood platelet aggregation. This pattern of responses may be caused by the combination of ferutinin's Ca(2+) ionophoric and estrogenic properties.
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Affiliation(s)
- Maria Zamaraeva
- Faculty of Biology and Chemistry, University of Bialystok, Świerkowa 20B, PL 15-950 Białystok, Poland
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18
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Combination of raloxifene, aspirin and estrogen as novel paradigm of hormone replacement therapy in rabbit model of menopause. Acta Pharmacol Sin 2011; 32:1031-7. [PMID: 21765446 DOI: 10.1038/aps.2011.87] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
AIM To assess a novel hormone replacement therapy (HRT) paradigm using raloxifene, aspirin combined with estrogen in rabbit model of menopause. METHODS Female New Zealand white rabbits were ovariectomized or sham-operated. The ovariectomized rabbits were divided into 7 groups: estradiol valerate (E(2)), raloxifene, aspirin, E(2) /raloxifene, E(2)/aspirin, E(2) /raloxifene/aspirin and vehicle. Two weeks after the operation, the rabbits were administered the above drugs for 12 weeks. Then, the mammary glands were examined histologically, uterus was weighted, and blood sample was collected for analyzing the levels of estrogen, serum lipids and monocyte chemoattractant protein (MCP)-1, and platelet aggregation. The aortic tissue was examined morphometrically. RESULTS Compared with E(2) 0.1 mg·kg(-1)·d(-1) treatment alone, the pairing of raloxifene 10 mg·kg(-1)·d(-1) with E(2) significantly decreased the extent of mammary gland branches and ducts (5.53%±1.23% vs 15.4%±2.17%, P<0.01), as well as the uterine weight (2.16±0.35 g vs 4.91±0.75 g, P<0.01). However, E(2)/raloxifene or E(2) alone treatment significantly stimulated platelet aggregation relative to vehicle group. Addition of aspirin 5 mg·kg(-1)·d(-1) reduced platelet aggregation to almost the same level as the vehicle group. E(2) treatment exerted a positive effect on serum lipids and MCP-1, and a regression in aortic intimal plaque size compared to the vehicle. Raloxifene reinforced the positive effects of E(2). CONCLUSION The combination of raloxifene, aspirin and E(2) exhibits positive lipid, MCP-1 and atherosclerotic responses with minimal stimulation of breast and uterine tissues as well as platelet aggregation in a rabbit model of the menopause.
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19
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Boldo A, White WB. Blood pressure effects of the oral contraceptive and postmenopausal hormone therapies. Endocrinol Metab Clin North Am 2011; 40:419-32, ix. [PMID: 21565676 DOI: 10.1016/j.ecl.2011.01.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Oral contraceptives and postmenopausal hormone therapy may induce hypertension through multiple mechanisms, including sodium and volume retention. Numerous studies have shown significant increases in blood pressure (BP) with the chronic administration of oral contraceptives as well as reversibility with discontinuation. The effects of different classes of oral contraceptive agents and hormonal replacement therapy on BP and associated effects on other cardiovascular risk factors are covered in this article. Novel hormonal replacement therapy that lowers BP is also discussed.
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Affiliation(s)
- Angela Boldo
- Division of Endocrinology, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA
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20
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Melamed N, Yogev Y, Bouganim T, Altman E, Calatzis A, Glezerman M. The effect of menstrual cycle on platelet aggregation in reproductive-age women. Platelets 2010; 21:343-7. [PMID: 20433309 DOI: 10.3109/09537101003770595] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Our aim was to assess the change in platelet activity along the menstrual cycle. We conducted a prospective observational study. The study group included 16 healthy women with regular menstrual cycles, which were compared to a control group of 14 healthy males. Exclusion criteria were age <18 years or >45 years, use of oral contraceptives or any other forms of hormonal therapy and medical disorders or medications that might affect platelet aggregation. Blood samples were taken from each of the women at four different phases of the menstrual cycle: day 1 +/- 1, day 7 +/- 1, day 14 +/- 1, and day 21 +/- 1. A single blood sample was taken from the males. Platelet aggregation was assessed in whole blood samples using the Multiplate analyzer with three different agonists (ADP, arachidonic acid (AA), and thrombin-receptor activating peptide (TRAP)). Platelet aggregation for each of the women at each of the phases of the menstrual cycle was expressed as the percentage change from the day 1 +/- 1 value. A total of 390 aggregation assays were performed. The mean aggregation activity was significantly higher in females compared with males, irrespective of the agonist used. For the TRAP and the ADP agonists, the relative platelet activity decreased along the menstrual cycle from day 1 towards day 21 and from day 7 towards day 21, respectively, although differences reached statistical significance only for day 21 (-12.4% +/- 3.2%, P < 0.05 for TRAP, and -9.5% +/- 3.9%, P < 0.05 for ADP). When using AA to induce platelet aggregation, the relative platelet activity was highest around the time of ovulation (11.0% +/- 4.7%) and was significantly lower on day 21 (-8.5% +/- 6.7%, P < 0.05). In conclusion, platelet aggregation activity is higher in females compared with males. The association between the phase of the menstrual cycle and platelet activity appears to vary with the type of agonist, but platelet aggregation is consistently lowest in the mid-luteal phase irrespective of the agonist used.
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Affiliation(s)
- Nir Melamed
- Helen Schneider Hospital for Women, Rabin Medical Center, Petach Tikva, & Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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21
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Wu GJ, Lee JJ, Chou DS, Jayakumar T, Hsiao G, Chen WF, Sheu JR. Inhibitory signaling of 17β-estradiol in platelet activation: the pivotal role of cyclic AMP-mediated nitric oxide synthase activation. Eur J Pharmacol 2010; 649:140-9. [PMID: 20883689 DOI: 10.1016/j.ejphar.2010.09.055] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Revised: 06/01/2010] [Accepted: 09/20/2010] [Indexed: 10/19/2022]
Abstract
Arterial thromboses are mostly composed of platelets adherent to ruptured endothelial surfaces. Platelets are anucleated cells; therefore, they represent an excellent and unique model to selectively investigate the signaling pathways mediating the nongenomic effects of estrogen. The aim of this study was to examine the signal transduction pathways of 17β-estradiol in preventing platelet activation. In this study, 17β-estradiol (5~10 μM) exhibited more-potent activity of inhibiting platelet aggregation stimulated by collagen than other agonists (i.e., thrombin). 17β-Estradiol-inhibited collagen-stimulated platelet activation accompanied by [Ca(2+)]i mobilization, thromboxane A₂ (TxA₂) formation, and phospholipase C (PLC)γ2, protein kinase C (PKC), and p38 mitogen-activated protein kinase (MAPK) phosphorylation. 17β-Estradiol markedly increased cyclic AMP and cyclic GMP levels, nitric oxide (NO) release, vasodilator-stimulated phosphoprotein (VASP) phosphorylation, and endothelial nitric oxide synthase (eNOS) expression. SQ 22536, an inhibitor of adenylate cyclase, markedly reversed the 17β-estradiol-mediated effects (i.e., platelet aggregation, and PLCγ2, VASP, and eNOS phosphorylation). Furthermore, ICI 182,780, a pure estrogen receptor antagonist, also reversed the 17β-estradiol-mediated effects on platelet aggregation and eNOS activation. In conclusion, the most important findings of this study demonstrate for the first time that the inhibitory effect of 17β-estradiol in platelet activation involves activation of the cyclic AMP-eNOS/NO-cyclic GMP pathway, resulting in inhibition of PLCγ2 and p38 MAPK activation, which may lower the incidence of cardiovascular events in postmenopausal women.
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Affiliation(s)
- Gong-Jhe Wu
- Department of Anesthesiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan
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22
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Rosin C, Brunner M, Lehr S, Quehenberger P, Panzer S. The formation of platelet–leukocyte aggregates varies during the menstrual cycle. Platelets 2009; 17:61-6. [PMID: 16308189 DOI: 10.1080/09537100500227021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Platelet-leukocyte aggregates are considered to play a significant role in blood coagulation and inflammatory processes. We hypothesized that hormonal changes during the menstrual cycle affect the formation of heterotypic aggregates and therefore may constitute cycle-dependent variations of the susceptibility for thromboembolic events and inflammatory disease. We therefore measured platelet-leukocyte interaction by the determination of platelet-leukocyte aggregates (PLA), platelet P-Selectin expression, and platelet fibrinogen receptor activation by PAC-1 binding in 20 healthy women during their menstrual cycle by flow cytometry. The number of platelet-granulocyte aggregates (PGA) and platelet-monocyte aggregates (PMA) was higher at ovulation compared to any other time-point of the menstrual cycle (p = 0.005, p = 0.022, respectively). Likewise, P-Selectin expression peaked on day 14 (p = 0.040). The course of PLA formation during the menstrual cycle followed the course of estrogen levels, strongly suggesting direct effects of estrogen on platelet-leukocyte interaction. The susceptibility to form platelet-leukocyte aggregates that are inducible in vitro by a suboptimal concentration of thrombin receptor activating peptide-6 decreased slightly during the transition from day 1 to 14 (p = 0.040). These data indicate that platelet function varies during particular phases of the normal menstrual cycle.
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Affiliation(s)
- Christiane Rosin
- Clinic for Blood Group Serology, Medical University Vienna, Vienna, Austria
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23
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Abstract
A large body of evidence suggests hormone replacement therapy (HRT) reduces cardiovascular risk in postmenopausal women. It is, however, associated with serious side effects, such as increased risk of breast and endometrial cancer. This has likely caused uneasiness among both women and health care providers. A new class of compounds, called selective estrogen receptor modulators (SERMs), have emerged. Through their interactions at the estrogen receptor level they have become a class of compounds distinct from estrogen. While they share similar effects with estrogen on such factors as lipid profile and bone density, they affect other tissues differently. Specifically, they do not induce endometrial hyperplasia and are therefore not associated with endometrial cancer. In vitro studies have also shown that they inhibit lipoprotein oxidation and vascular smooth muscle cell proliferation. The cumulative effects of these compounds may prove quite beneficial in reducing cardiovascular risk in postmenopausal women while avoiding serious side effects. This may, in turn, ease much of the anxiety surrounding the issue of HRT. Clinical trials are presently being conducted to evaluate the effectiveness of raloxifene, a SERM, on cardiovascular risk reduction in postmenopausal women.
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Affiliation(s)
- J A Guzzo
- Department of Medicine, University of North Carolina, Chapel Hill 27599, USA
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The transactivating function 1 of estrogen receptor alpha is dispensable for the vasculoprotective actions of 17beta-estradiol. Proc Natl Acad Sci U S A 2009; 106:2053-8. [PMID: 19188600 DOI: 10.1073/pnas.0808742106] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Full-length 66-kDa estrogen receptor alpha (ERalpha) stimulates target gene transcription through two activation functions (AFs), AF-1 in the N-terminal domain and AF-2 in the ligand binding domain. Another physiologically expressed 46-kDa ERalpha isoform lacks the N-terminal A/B domains and is consequently devoid of AF-1. Previous studies in cultured endothelial cells showed that the N-terminal A/B domain might not be required for estradiol (E2)-elicited NO production. To evaluate the involvement of ERalpha AF-1 in the vasculoprotective actions of E2, we generated a targeted deletion of the ERalpha A/B domain in the mouse. In these ERalphaAF-1(0) mice, both basal endothelial NO production and reendothelialization process were increased by E2 administration to a similar extent than in control mice. Furthermore, exogenous E2 similarly decreased fatty streak deposits at the aortic root from both ovariectomized 18-week-old ERalphaAF-1(+/+) LDLr(-/-) (low-density lipoprotein receptor) and ERalphaAF-1(0) LDLr (-/-) mice fed with a hypercholesterolemic diet. In addition, quantification of lesion size on en face preparations of the aortic tree of 8-month-old ovariectomized or intact female mice revealed that ERalpha AF-1 is dispensable for the atheroprotective action of endogenous estrogens. We conclude that ERalpha AF-1 is not required for three major vasculoprotective actions of E2, whereas it is necessary for the effects of E2 on its reproductive targets. Thus, selective ER modulators stimulating ERalpha with minimal activation of ERalpha AF-1 could retain beneficial vascular actions, while minimizing the sexual effects.
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Sarabia SF, Raya JL, Hoogeveen RC, Bray PF. Human platelets differentially concentrate estradiol, estrone and testosterone. J Thromb Haemost 2008; 6:703-5. [PMID: 18194416 DOI: 10.1111/j.1538-7836.2008.02898.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Chen L, Liu Y, Cui B, Mi Q, Huang Y, Fan L, Chen Q, Tang J, Ferro A, Ji Y. 17Beta-oestradiol partially attenuates the inhibition of nitric oxide synthase-3 by advanced glycation end-products in human platelets. Clin Exp Pharmacol Physiol 2007; 34:972-8. [PMID: 17714081 DOI: 10.1111/j.1440-1681.2007.04680.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
1. Diabetes mellitus predisposes to and female sex protects against arterial thrombosis. The aim of the present study was to determine whether advanced glycation end-products (AGE), which accumulate in diabetes, impair platelet function through effects on platelet nitric oxide (NO) generation and whether this can be prevented by 17beta-oestradiol. 2. Aggregation responses of human platelet-rich plasma to ADP were determined in the absence or presence of 200 mg/L AGE-modified albumin (AGE-albumin), 10(-5) mol/L 17beta-oestradiol and 10(-5) mol/L ICI 182 780 (the pure oestrogen receptor antagonist). 3. Intraplatelet cGMP, an index of bioactive NO, was measured by radioimmunoassay and expression of nitric oxide synthase (NOS)-3, phosphoserine-1177-NOS-3 and O-glycosylated NOS-3 was quantified by western blotting in response to these same treatments. 4. Advanced glycation end-products-albumin increased platelet aggregatory responses to ADP. This increase was largely prevented by 17beta-oestradiol. Advanced glycation end-products-albumin decreased and 17beta-oestradiol increased intraplatelet NO-attributable cGMP and 17beta-oestradiol attenuated the AGE-albumin-induced decrease in NO-attributable cGMP. Despite no effect on NOS-3 expression, AGE-albumin decreased and 17beta-oestradiol increased phosphoserine-1177-NOS-3 and 17beta-oestradiol largely prevented the decrease in phosphoserine-1177-NOS-3 induced by AGE-albumin. Alone, AGE-albumin increased O-glycosylation of NOS-3 by N-acetylglucosamine, an effect largely inhibited by 17beta-oestradiol. 5. In conclusion, AGE-albumin inhibits platelet NO biosynthesis through effects on serine phosphorylation and O-glycosylation of platelet NOS-3 and this may explain, at least in part, the increase in platelet aggregability induced by AGE-albumin. These effects of AGE-albumin are largely prevented by 17beta-oestradiol. These actions may contribute to the effects of diabetes and sex on arterial thrombosis in vivo.
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Affiliation(s)
- Lu Chen
- Laboratory of Reproductive Medicine, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
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27
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Cano A, Hermenegildo C, Oviedo P, Tarín JJ. Selective estrogen receptor modulators and risk for coronary heart disease. Climacteric 2007; 10:97-111. [PMID: 17453858 DOI: 10.1080/13697130701258804] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Coronary heart disease (CHD) is the leading cause of death in women in most countries. Atherosclerosis is the main biological process determining CHD. Clinical data support the notion that CHD is sensitive to estrogens, but debate exists concerning the effects of the hormone on atherosclerosis and its complications. Selective estrogen receptor modulators (SERMs) are compounds capable of binding the estrogen receptor to induce a functional profile distinct from estrogens. The possibility that SERMs may shift the estrogenic balance on cardiovascular risk towards a more beneficial profile has generated interest in recent years. There is considerable information on the effects of SERMs on distinct areas that are crucial in atherogenesis. The complexity derived from the diversity of variables affecting their mechanism of action plus the differences between compounds make it difficult to delineate one uniform trend for SERMs. The present picture, nonetheless, is one where SERMs seem less powerful than estrogens in atherosclerosis protection, but more gentle with advanced forms of the disease. The recent publication of the Raloxifene Use for The Heart (RUTH) study has confirmed a neutral effect for raloxifene. Prothrombotic states may favor occlusive thrombi at sites occupied by atheromatous plaques. Platelet activation has received attention as an important determinant of arterial thrombogenesis. Although still sparse, available evidence globally suggests neutral or beneficial effects for SERMs.
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Affiliation(s)
- A Cano
- Department of Pediatrics, Obstetrics and Gynecology, University of Valencia, Valencia, Spain
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28
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Arias RD. Cardiovascular health and the menopause: the gynecologist as the patients' interface. Climacteric 2007; 9 Suppl 1:6-12. [PMID: 16899438 DOI: 10.1080/13697130600916148] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The large decrease in estrogen following menopause appears to explain the dramatic increase in cardiovascular disease (CVD) in postmenopausal women. Gynecologists are well placed to play a primary role in the diagnosis, prevention and management of CVD in these patients; this role may include advice on lifestyle changes, and, if appropriate, prescribing preventative treatments such as hormone replacement therapy (HRT) and lipid-lowering drugs. The use of estrogen replacement therapy (ERT) to prevent CVD is supported by a number of observational studies. However, recently, large, randomized trials gave unexpected, conflicting data on the cardiovascular benefits of HRT, leading to confusion, and influencing both patient and clinical perceptions regarding the role of HRT postmenopause. These different outcomes may be due to differences in the HRT regimens, mean age and mean time from menopause at enrollment, duration of therapy, and patient selection bias in observational studies. A 'unified hypothesis' consistent with findings from all studies has now been developed: HRT initiated at the time of the menopause prevents CVD, whereas HRT initiated years after the menopause seems to increase CHD events. This knowledge is essential for gynecologists making clinical decisions regarding HRT use.
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Affiliation(s)
- R D Arias
- Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, USA
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Akarasereenont P, Tripatara P, Chotewuttakorn S, Palo T, Thaworn A. The effects of estrone, estradiol and estriol on platelet aggregation induced by adrenaline and adenosine diphosphate. Platelets 2007; 17:441-7. [PMID: 17074719 DOI: 10.1080/09537100600745302] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The impact of estrogens on the cardiovascular system and their ability to regulate platelet functions remains controversial. Changes in platelet functions could contribute to thrombotic risk associated with estrogen treatments. Here, we investigated the effects of various forms of estrogen, including estrone (E1), estradiol (E2) and estriol (E3), on platelet aggregation induced by standard agonists (adrenaline and adenosine diphosphate). Platelet-rich plasma (PRP) was prepared from citrated blood donated by 25 normal volunteers. The study on platelet aggregation was carried out in 96-well flat-bottom microtitre plates and assessed using a microplate reader. For studying the effects of each estrogen, PRP was preincubated with 1, 10 and 100 nM of E1, E2 and E3 at 37 degrees C for 20 min, and then coincubated with normal saline (control untreated PRP), adrenaline (ADR) or adenosine diphosphate (ADP) in the microplate. Platelet aggregation was then measured every minute for 8 min. None of the estrogens (E1, E2 and E3) affected platelet aggregation in untreated PRP. Interestingly, only E1 and E3 can synergize the increased platelet aggregation by either ADR or ADP, while the effects of E2 on the increased platelet aggregation by either ADR or ADP depended on internal factors such as endogenous estradiol and platelet aggregated state. Thus, for the rational use of these internal factors for estrogen use, especially E2, in clinical applications, such as hormone replacement therapy, may need evaluation of thrombotic risk.
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Affiliation(s)
- Pravit Akarasereenont
- Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Prannok Rd, Bangkok 10700, Thailand.
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Massheimer V, Polini N, Alvarez C, Benozzi S, Rauschemberger MB, Sellés J. Signal transduction pathways involved in non-genomic action of estrone on vascular tissue. Steroids 2006; 71:857-64. [PMID: 16860831 DOI: 10.1016/j.steroids.2006.05.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Revised: 05/12/2006] [Accepted: 05/29/2006] [Indexed: 11/29/2022]
Abstract
Previously we demonstrated that estrone non-genomically regulates rat aortic NOS and COX activity and that this effect depends on ovarian activity. The purpose of the present study was to characterize this effect and investigate the participation of phospholipase C and phophatidylinositol-3-kinase system in the intracellular transduction pathway involved in the response. Using aortic strips isolated from female fertile rats we showed that estrone stimulate nitric oxide synthase and cyclooxygenase in a short time interval (5-20 min), and that NO production was dependent in part on PGI2 production since 1 microM indomethacin significantly reduced this free radical production. Injection of 17-beta-estradiol to ovariectomized rats restored tissue capacity to rapidly increase NO production in response to "in vitro" treatment with 1 nM estrone. We also demonstrated that in aortic strips isolated from intact animals estrone elicited a rapid phospholipase C activation, inducing a biphasic increase in diacylglycerol generation (peaking at 45 s and 5 min). The presence of protein kinase C inhibitor chelerythrine did not prevent the increase of NO released in response to hormone treatment. We proved that PI3K-Akt system does not mediate NOS and COX activation. However, PLC activation was dependent on PI3K since presence of LY 294002 in the incubation medium abolished estrone-induced DAG increment. We concluded that, estrone rapid action on vascular tissue involves a cross talk between NOS and COX system, and the activation of PLC/DAG/PKC transduction pathways.
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Affiliation(s)
- Virginia Massheimer
- Cátedra de Análisis Clínicos II, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur., San Juan 670, B8000ICN Bahía Blanca, Argentina.
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Oron G, Ben-Haroush A, Hod M, Orvieto R, Bar J. Serum-Soluble CD40 Ligand in Normal Pregnancy and in Preeclampsia. Obstet Gynecol 2006; 107:896-900. [PMID: 16582129 DOI: 10.1097/01.aog.0000206206.99212.9e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Soluble CD40 ligand is a transmembrane protein shed from activated platelets that is involved in the activation of endothelial cells. Findings that estradiol (E2) has an inhibitory effect on inflammation and platelet function and that serum E2 levels are low in women with preeclampsia prompted us to investigate the association between soluble CD40 ligand and serum E2 levels in normal pregnancy and in preeclampsia. METHODS A case-control single-center design was used. The sample included 22 women with severe preeclampsia, 22 matched normotensive pregnant women, and 22 nonpregnant women. Enzyme immunoassay was used to measure soluble CD40 ligand. RESULTS Significantly higher levels of soluble CD40 ligand were detected in the nonpregnant women (23,767 +/- 15,637 pg/mL) and in the women with preeclampsia (21,025 +/- 45,386 pg/mL) than in the normotensive pregnant women (8,292 +/- 5,926 pg/mL) (P = .026). No significant correlation between soluble CD40 ligand levels and E2 levels was observed. CONCLUSION The higher levels of soluble CD40 ligand detected in women with preeclampsia may indicate an exaggerated activation of platelets and endothelial cells. LEVEL OF EVIDENCE II-2.
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Affiliation(s)
- Galia Oron
- Perinatal Division, Department of Obstetrics and Gynecology, Rabin Medical Center, Beilinson Campus, Petah Tiqwa, Israel.
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Du XJ, Fang L, Kiriazis H. Sex dimorphism in cardiac pathophysiology: experimental findings, hormonal mechanisms, and molecular mechanisms. Pharmacol Ther 2006; 111:434-75. [PMID: 16439025 DOI: 10.1016/j.pharmthera.2005.10.016] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Accepted: 10/25/2005] [Indexed: 11/30/2022]
Abstract
The higher cardiovascular risk in men and post-menopausal women implies a protective action of estrogen. A large number of experimental studies have provided strong support to this concept. However, the recent clinical trials with negative outcomes regarding hormone replacement therapy call for "post hoc" reassessment of existing information, models, and research strategies as well as a summary of recent findings. Sex steroid hormones, in particular estrogen, regulate numerous processes that are related to the development and progression of cardiovascular disease through a variety of signaling pathways. Use of genetically modified models has resulted in interesting information on diverse actions mediated by steroid receptors. By focusing on experimental findings, we have reviewed hormonal, cellular, and signaling mechanisms responsible for sex dimorphism and actions of hormone replacement therapy and addressed current limitations and future directions of experimental research.
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Affiliation(s)
- Xiao-Jun Du
- Experimental Cardiology Laboratory, Baker Heart Research Institute, 75 Commercial Road, Melbourne, Victoria 3004, Australia.
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Littleton-Kearney MT, Gaines JM, Callahan KP, Murphy SJ, Hurn PD. Effects of estrogen on platelet reactivity after transient forebrain ischemia in rats. Biol Res Nurs 2005; 7:135-45. [PMID: 16267375 PMCID: PMC2678714 DOI: 10.1177/1099800405276832] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Estrogen's prothrombotic effects are of increasing concern, particularly in stroke risk and recovery. Using an ischemic rodent model, the authors sought to determine (a) if estrogen replacement increases postischemic platelet reactivity, (b) if changes in estrogen status alter intraplatelet endothelial nitric oxide synthase (eNOS) synthesis, and (c) if estrogen-mediated effects on platelets alter cerebral blood flow during reperfusion. Intact (I), ovariectomized (OVX), and OVX + 17 beta-estradiol (E50) rats were subjected to 30 min of forebrain ischemia and 60 min of reperfusion. Using the platelet activation marker P-selectin, postischemic platelet reactivity was quantified by flow cytometry. In a separate cohort (I, OVX, E50), the authors quantified platelet eNOS by Western blot. Another cohort (OVX, E50) was subjected to ischemia/reperfusion, and cerebral blood flow was determined using the iodoantipyrine technique. Collagen-stimulated platelet P-selectin expression was increased in the OVX rats at 60 min of reperfusion, and this effect was reversed by estrogen treatment. No differences in platelet eNOS expression were detected among groups. Cerebral blood flow at 60 min reperfusion was comparable between the OVX and the E50 rats. The authors conclude that during reper-fusion, estrogen deficiency increases postischemic platelet sensitivity to stimuli in estrogen-deficient rats. Estrogen treatment mitigates effects of estrogen loss on platelets, but this early effect is apparently not caused by intraplatelet eNOS depression. Neither estrogen deficiency nor estrogen treatment changes early postischemic regional brain blood flow. In this rodent global cerebral ischemic model, physiologic doses of estrogen are not deleterious to platelet reactivity and may initially reduce postischemic platelet reactivity.
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Abstract
Hormone replacement therapy (HRT) is effective in suppressing postmenopausal symptoms and, in the past, many have claimed that it is cardioprotective. It was thought that the lower incidence of cardiovascular disease in premenopausal women was related to the cardioprotective effect of estrogen. Many of these studies were, however, observational studies. HRT alters many cardiovascular parameters, most beneficially. The mixed effect on these parameters make the overall result on cardiovascular risk difficult to predict. However, recent randomized, placebo-controlled trials have shown not only that HRT does not confer cardioprotection, but that it actually increases one's cardiovascular risk in the short term. Based on the current evidence, HRT should not be recommended in the hope that it will protect postmenopausal women against coronary heart disease.
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Affiliation(s)
- Aun-Yeong Chong
- University Department of Medicine, City Hospital, Birmingham, England
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Selles J, Polini N, Alvarez C, Massheimer V. Novel action of estrone on vascular tissue: regulation of NOS and COX activity. Steroids 2005; 70:251-6. [PMID: 15784280 DOI: 10.1016/j.steroids.2004.10.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2004] [Revised: 10/20/2004] [Accepted: 10/25/2004] [Indexed: 01/21/2023]
Abstract
The hypothesis tested in the present work is that estrone non-genomically regulates aortic nitric oxide synthase (NOS) and cyclooxygenase (COX) activities in female rats, and that such regulation depends on ovarian function. We found that physiological concentrations of estrone (E(1)) (0.1-10nM) significantly increased nitric oxide (NO) production (133 and 163% above control). The stimulatory action of E(1) on NOS activity was independent of calcium influx since the increase in NO elicited by the hormone was not affected by EGTA or verapamil. When COX activity was measured, we observed that estrone enhanced thromboxane (TXB(2)) production and prostacyclin (PGI(2)) release, but not prostaglandin (PGF(2), PGD(2), and PGE(2)) synthesis. Finally we demonstrated that the hormonal effect on NOS activity was not detected in rat aortic strips (RAS) isolated from animals deprived of ovarian activity (FR(-)) or ovariectomized rats (OVX). These results suggest that estrone exerts a direct, non-genomic action on rat aortic metabolism, which involves NOS and COX activation and depends on ovarian activity.
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Affiliation(s)
- Juana Selles
- Cátedra de Analisis Clínicos II, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, B8000ICN Bahia Blanca, Argentina
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Kandler B, Maitz P, Fischer MB, Watzek G, Gruber R. Platelets can neutralize hydrogen peroxide in an acute toxicity model with cells involved in granulation tissue formation. Bone 2005; 36:671-7. [PMID: 15784190 DOI: 10.1016/j.bone.2005.01.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2004] [Revised: 01/15/2005] [Accepted: 01/24/2005] [Indexed: 11/17/2022]
Abstract
Platelets play a key role in the replacement of the blood clot with granulation tissue during the early steps of bone regeneration. We hypothesized that activated platelets can neutralize locally produced reactive oxygen species, thereby protecting cells involved in granulation tissue formation. The potential of platelet-released supernatant (PRS) to neutralize hydrogen peroxide (H(2)O(2)) was tested in an acute toxicity model with osteogenic, inflammatory, and endothelial cells. In the human fetal osteoblastic cell line 1.19 (hFOB), considerable morphological changes, cell shedding, and dysfunction of the respiratory chain were observed when cells were exposed to 3 mM H(2)O(2). Caspase-3 and poly-(ADP-ribose)-polymerase were not activated, suggesting that cell death occurred by necrosis. Preincubation of osteogenic cells, leukocytes, or endothelial cells with PRS decreased the acute toxicity of H(2)O(2). The capacity of platelets to release H(2)O(2)-detoxifying activity was retained for up to 72 h. Aminotriazole, an inhibitor of catalase, decreased the cytoprotective activity of PRS, whereas blocking of glutathione peroxidase by mercaptosuccinate had no effect. These results suggest that platelet-released catalase can rapidly neutralize cytotoxic amounts of H(2)O(2), a process that may play a role during the early stages of bone regeneration.
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Affiliation(s)
- Barbara Kandler
- Department of Oral Surgery, Medical University of Vienna, Austria
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García-Martínez MC, Labiós M, Hermenegildo C, Tarín JJ, O'Connor E, Cano A. The effect of hormone replacement therapy on Ca2+ mobilization and P-selectin (CD62P) expression in platelets examined under flow cytometry. Blood Coagul Fibrinolysis 2005; 15:1-8. [PMID: 15166936 DOI: 10.1097/00001721-200401000-00001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A series of events, such as increase of cytoplasmic free calcium (Ca2+) and expression of P-selectin (CD62P), an adhesion molecule, on the platelet surface, are significant indicators of platelet activation. We have used flow cytometry to examine Ca2+ mobilization and CD62P expression in platelets in whole blood obtained in women prior to, and after, different forms of hormone replacement therapy. Thirty-two women completed a protocol consisting of two consecutive 1-month periods under oestradiol (E2), administered orally (2 mg/day) or transdermally (50 microg/day) in random order, followed by a 4-week transdermal sequential regime, in which, during the last 14 days, either progesterone (300 mg/day) or medroxyprogesterone acetate (5 mg/day) was added to the 50 microg/day E2, administered orally in random order. None of the hormonal combinations determined significant changes in Ca2+ mobilization or CD62P expression in non-stimulated platelets. However, stimulation of platelets with adenosine diphosphate, but not with thrombin, caused a significant increase in cytoplasmic Ca2+ concentration during treatment with transdermal E2 plus progesterone. Also when stimulating with thrombin, transdermal E2 was more active than oral E2 in increasing CD62P expression, a difference that was not reduced by the addition of progestogens. In conclusion, hormone replacement therapy only increased Ca2+ mobilization or CD62P expression in stimulated platelets, and then followed a varied pattern that was dependent on the stimulant and on the specific hormonal formulation.
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Affiliation(s)
- Maria Cinta García-Martínez
- Department of Pediatrics, Obstetrics and Gynecology, Facultad de Medicina, Universidad de Valencia, Valencia, Spain
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Suwannaprapha P, Chaisri U, Riyong D, Maneerat Y. Improvement of Function and Morphology of Tumor Necrosis Factor-.ALPHA. Treated Endothelial Cells With 17-.BETA. Estradiol A Preliminary Study for a Feasible Simple Model for Atherosclerosis. Circ J 2005; 69:730-8. [PMID: 15914954 DOI: 10.1253/circj.69.730] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Dysfunction of endothelial cells (EC) to produce endothelial nitric oxide synthase (eNOS) by tumor necrosis factor-alpha (TNF-alpha) causes critical features of vascular inflammation associated with several disease states (eg, atherosclerosis including increased platelet aggregation and adhesion on EC, elevated adhesion molecules and enhanced inflammatory cells binding to EC). 17-beta estradiol (E2) can stimulate eNOS production and improve the critical features of atherosclerosis. Using TNF-alpha and E2, we attempted to develop an in vitro vascular model for studying atherosclerosis. METHODS AND RESULTS Human umbilical vein endothelial cells (HUVEC) grown in transwells were cocultured with smooth muscle cells in a 24-well plate to mimic the major components of the vascular wall. The model was incubated with TNF-alpha (10 ng/ml) for 12 h, prior exposed to E2 (100 pg/ml) for 6-12 h, then investigated by transmission and scanning electron microscopes. The result indicated recovered morphology with good tight junction, and decreased platelet adhesion was noted in defective HUVEC after E2 treatment. CONCLUSION 17-beta estradiol was represented as an antiatherosclerogenic agent to demonstrate feasibility of the model. Although our finding focused only on the endothelium, this would be the basis for our future studies to develop ex vivo continuous perfusion of human vessel segments for a further atherosclerosis study.
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Affiliation(s)
- Parin Suwannaprapha
- Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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Vitseva O, Flockhart DA, Jin Y, Varghese S, Freedman JE. The Effects of Tamoxifen and Its Metabolites on Platelet Function and Release of Reactive Oxygen Intermediates. J Pharmacol Exp Ther 2004; 312:1144-50. [PMID: 15509721 DOI: 10.1124/jpet.104.076315] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Tamoxifen is effective in the prevention and treatment of breast cancer, but its use is associated with an increased risk of thrombosis. The mechanism for this effect is unknown. Reactive oxygen intermediates enhance platelet-dependent thrombosis, and in oncological studies, tamoxifen has been shown to increase production of reactive oxygen species. Therefore, the effects of tamoxifen and its bioactive metabolites on platelet activity and platelet reactive oxygen species were determined. Platelets were incubated with tamoxifen or the metabolites 4-hydroxy-tamoxifen (4-OH), N-desmethyl tamoxifen, or 4-hydroxy-N-desmethyl tamoxifen (endoxifen). Tamoxifen metabolites have been previously shown to possess enhanced bioactivity, and consistent with this observation, tamoxifen metabolites but not tamoxifen modestly increased platelet aggregation. These effects were similar with platelets isolated from male or female subjects. Platelet nitric oxide release or cGMP levels were not altered by incubation with tamoxifen or any of its metabolites. Incubation with tamoxifen metabolites increased stimulation-dependent platelet superoxide release [8.1 +/- 1.6 arbitrary units (a.u.) for control versus 15.2 +/- 3.5 a.u. for 4-OH; P < 0.01]. Coincubation with a superoxide dismutase mimetic eliminated the tamoxifen metabolite-induced enhancement of platelet aggregation. Corresponding to increased superoxide release, incubation with tamoxifen metabolites enhanced the functional activation of NADPH oxidase as determined by phosphorylation of its subunits p47(phox) and p67(phox). In summary, incubation of platelets with the active metabolites of tamoxifen increases stimulation-dependent superoxide release through a NADPH oxidase-dependent mechanism. This results in modest changes in platelet function and seems to be consistent with previous oncological studies demonstrating tamoxifen-dependent increase in reactive oxygen species generation.
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Affiliation(s)
- Olga Vitseva
- Boston University School of Medicine, 715 Albany St., W507, Boston, MA 02118, USA
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Gou YL, Ho ALS, Rowlands DK, Chung YW, Chan HC. Effects of Bak Foong Pill on blood coagulation and platelet aggregation. Biol Pharm Bull 2003; 26:241-6. [PMID: 12576687 DOI: 10.1248/bpb.26.241] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effects of Bak Foong Pill (BFP, also known as Bai Feng Wan), a preparation of crude drugs in wide clinical use for treatment of gynecological disorders, on blood coagulation and platelet aggregation were investigated. The anticoagulant effect of BFP was evaluated by using thrombin time (TT), prothrombin time (PT), and activated partial thromboplastin time (APTT) assays. Results showed that BFP 70% ethanol extract (BFP-E-ext) significantly prolonged the TT in a dose-dependent manner with values of 17.6, 38.3, and 50.4 s at concentrations of 4.0, 6.0, and 12.0 mg/ml, respectively. Whereas, the BFP-E-ext did not show significant prolonging effect in PT and APTT assays. The results suggest that the anticoagulant effect of BFP is mediated by directly blocking thrombin, the key enzyme in the blood coagulation cascade. BFP-E-ext significantly inhibited platelet aggregation induced by collagen and adenosine diphosphate (ADP) with inhibition percentages of 74 and 52% at a concentration of 6.0 mg/ml, respectively, whereas, it exhibited a weak inhibitory activity on platelet aggregation induced by archidonic acid (AA). Comparing to BFP-E-ext, the effects of BFP aqueous extract (BFP-W-ext) on both anticoagulant and antiplatelet activities were significantly less potent. Moreover, the effects of the 26 ingredients of BFP on blood coagulation and platelet aggregation were separately evaluated with 19 ingredient herbs exhibiting anticoagulant effect and 10 exhibiting antiplatelet effect. The anticoagulant and antiplatelet effects of BFP were collectively demonstrated by in vivo assays showing prolonged bleeding times after BFP treatment for two weeks. The results of the present studies may provide explanations for beneficial effects of BFP on the circulation and indicate its potential use for cardiovascular diseases.
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Affiliation(s)
- Yu Lin Gou
- Epithelial Cell Biology Research Center, Department of Physiology, The Chinese University of Hong Kong, Hong Kong
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Tsuda K, Kinoshita-Shimamoto Y, Kimura K, Nishio I. Effect of oestrone on membrane fluidity of erythrocytes is mediated by a nitric oxide-dependent pathway: An electron paramagnetic resonance study. Clin Exp Pharmacol Physiol 2002; 29:972-9. [PMID: 12366388 DOI: 10.1046/j.1440-1681.2002.03764.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. It has been recognized that hormone replacement therapy (HRT) may have a beneficial effect on protection against cardiovascular diseases. Oestrone is the major component of conjugated equiline oestrogens, which are commonly used in HRT. The present study was performed in order to investigate the effects of oestrone on the membrane fluidity of erythrocytes by means of an electron paramagnetic resonance (EPR) and spin-labelling method. 2. In an in vitro study, oestrone significantly decreased the order parameter (S) for 5-nitroxide stearate (5-NS) and the peak height ratio (ho/h-1) for 16-nitroxide stearate (16-NS) obtained from EPR spectra of erythrocyte membranes. This finding indicated that oestrone may increase the membrane fluidity and improve the membrane microviscosity of erythrocytes. 3. The effect of oestrone was significantly potentiated by the nitric oxide (NO) donor s-nitroso-N-acetylpenicillamine and the cGMP analogue 8-bromo-cGMP. 4. In contrast, the change in membrane fluidity induced by oestrone was antagonized by the NO synthase inhibitors NG-nitro-l-arginine methyl ester and asymmetric dimethyl-l-arginine. 5. The results of the present study show that oestrone significantly increases membrane fluidity and improves the rigidity of cell membranes, which is partially mediated by a NO- and cGMP-dependent pathway. Furthermore, the data may be consistent with the hypothesis that oestrone could have a beneficial effect on the rheological behaviour of erythrocytes and have a crucial role in the regulation of the microcirculation.
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Affiliation(s)
- Kazushi Tsuda
- Division of Cardiology, Department of Medicine, Wakayama Medical University, Wakayama, Japan.
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Martina V, Bruno GA, Origlia C, Gaia D, Trucco F, Pescarmona G. Transdermal oestradiol replacement therapy enhances platelet constitutive nitric oxide synthase activity in postmenopausal women with type 2 diabetes mellitus. Clin Endocrinol (Oxf) 2002; 57:371-5. [PMID: 12201830 DOI: 10.1046/j.1365-2265.2002.01609.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine whether treatment with transdermal oestrogen replacement therapy (TERT) in postmenopausal women with type 2 diabetes mellitus was able to increase the activity of constitutive nitric oxide synthase (cNOS) in platelets. RESEARCH DESIGN AND METHODS Eighteen postmenopausal women with type 2 diabetes mellitus (group A) were studied in basal conditions (A1) and on the 10th day of the third month of a sequential opposed TERT (A2) evaluating platelet cNOS activity measured by the conversion of radiolabelled l-arginine to l-citrulline. As a control group (B) 25 normal postmenopausal women underwent the same treatment (B1 and B2 before and during treatment, respectively). RESULTS Basal values of platelet cNOS activity were superimposable (0.6 +/- 0.1 vs. 0.7 +/- 0.1 fmol/min/109 plts, NS). During TERT, platelet cNOS activity rose in A and B (0.6 +/- 0.1 vs. 1.8 +/- 0.1 fmol/min/109 plts, P < 0.05 and 0.7 +/- 0.1 vs. 2.4 +/- 0.2, P < 0.001, A1 vs. A2 and B1 vs. B2, respectively). However, platelet cNOS activity of A2 did not reach the values of B2 (1.8 +/- 0.1 vs. 2.4 +/- 0.2 fmol/min/109 plts, P < 0.05; A2 vs. B2, respectively). CONCLUSIONS Sequential opposed transdermal oestrogen replacement therapy was able to increase platelet cNOS activity in postmenopausal women with type 2 diabetes mellitus, suggesting that its use might be positive in preventing cardiovascular pathologies.
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Jayachandran M, Miller VM. Ovariectomy upregulates expression of estrogen receptors, NOS, and HSPs in porcine platelets. Am J Physiol Heart Circ Physiol 2002; 283:H220-6. [PMID: 12063294 DOI: 10.1152/ajpheart.00950.2001] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Platelets participate in normal and pathological thrombotic processes. Hormone replacement in postmenopausal women is associated with increase risk for thrombosis. However, little is known regarding how platelets are affected by hormonal status. Nitric oxide (NO) modulates platelet functions and is modulated by hormones. Therefore, the present study was designed to determine how loss of ovarian hormones changes expression of estrogen receptors and regulatory proteins for NO synthase (NOS) in platelets. Estrogen receptors (ER alpha and ER beta), NOS, heat shock proteins 70 and 90 (HSP70 and HSP90), caveolin-1, -2, and -3, calmodulin, NOS activity, and cGMP were analyzed in a lysate of platelets from gonadally intact and ovariectomized female pigs. Expression of ER beta and ER alpha receptors, endothelial NOS (eNOS), HSP70, and HSP90 increased with ovariectomy. NOS activity and cGMP also increased; calmodulin was unchanged. Caveolins were not detected. These results suggest that ovarian hormones influence expression of estrogen receptors and eNOS in platelets. Changes in estrogen receptors and NOS could affect platelet aggregation in response to hormone replacement.
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Affiliation(s)
- Muthuvel Jayachandran
- Department of Surgery and Physiology and Biophysics, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Tanus-Santos JE, Desai M, Deak LR, Pezzullo JC, Abernethy DR, Flockhart DA, Freedman JE. Effects of endothelial nitric oxide synthase gene polymorphisms on platelet function, nitric oxide release, and interactions with estradiol. PHARMACOGENETICS 2002; 12:407-13. [PMID: 12142730 DOI: 10.1097/00008571-200207000-00008] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Impaired platelet-derived nitric oxide (NO) contributes to acute coronary syndromes by enhancing platelet recruitment and thrombus formation. Polymorphic variants of the endothelial NO synthase (eNOS) gene have been associated with cardiovascular diseases. To examine whether eNOS variants affect platelet-derived NO and platelet function, and to assess the effects of estradiol on platelet function, we studied platelets from 47 healthy caucasians who were genotyped for eNOS polymorphisms in the promoter region (T-786 C), in intron 4, and in exon 7 (Glu298Asp). Platelet aggregation, platelet-derived NO and superoxide production were measured in control samples and samples pretreated with 17-alpha-estradiol (10 nmol/l). The occurrence of variants in the promoter region (P = 0.002) or in exon 7 (P = 0.007), but not in intron 4 (P > 0.05), were associated with lower levels of platelet-derived NO. An increased (P = 0.047) release of superoxide was observed with platelets from subjects with the variant in the promoter region, but not with other eNOS genetic variants. The eNOS gene polymorphisms did not affect ADP-induced platelet aggregation (P > 0.05). However, estradiol significantly increased platelet aggregation (P = 0.004), and platelet-derived superoxide (P = 0.047) in individuals homozygous for the variant in exon 7, but not in subject with other genotypes. These data demonstrate that the eNOS variants in the promoter region and in exon 7 decrease platelet-derived NO and that estradiol significantly increases platelet aggregation in homozygous for the variant in exon 7 but not in subjects with other genotypes, suggesting that eNOS variants may influence the thrombotic response.
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Affiliation(s)
- Jose E Tanus-Santos
- Division of Clinical Pharmacology, Georgetown University Medical School, Washington, DC, USA.
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Martina V, Bruno GA, Zumpano E, Origlia C, Ferri M, Pescarmona GP. Platelet cyclic guanosine monophosphate production during menstrual cycle in healthy women. J Endocrinol Invest 2002; 25:334-7. [PMID: 12030604 DOI: 10.1007/bf03344014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
UNLABELLED The incidence of cardiovascular disease among women during their reproductive years is considerably less than in men and this difference decreases after menopause. Since in cultured endothelial cells and in platelets E2 increases nitric oxide (NO) production, it is possible that their cardioprotective effect may be mediated by NO. The aim of this study was to evaluate platelet cyclic guanosine monophosphate (cGMP), as a marker of NO production, during menstrual cycle. Fifteen women aged 26-40 yr were studied to evaluate: LH, FSH, E2, P and cGMP on the 5th follicular and 22nd luteal day of the cycle and during the ovulatory period. Platelet cGMP was evaluated in basal condition (3-isobuthyl 1-methylxanthine-IBMX) and with ionomycine (IONO) and sodium nitroprusside (SNP). RESULTS LH, FSH, E2 and P demonstrated the typical patterns of ovulatory cycle. During follicular and luteal IBMX, SNP and IONO phase were homogeneous while they increased during the ovulatory period. A correlation between IBMX cGMP and E2 (p<0.002, rs=0.456) was found. In conclusion the data show an increase in platelet cGMP during the ovulatory period and a correlation between E2 and cGMP suggesting that E2 modulates NO production. The cardioprotective effect of E2 may be, at least in part, mediated by the increase in NO production.
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Affiliation(s)
- V Martina
- Department of Internal Medicine, University of Turin, Italy.
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Lissin LW, Cooke JP. Maintaining the endothelium: preventive strategies for vessel integrity. PREVENTIVE CARDIOLOGY 2002; 4:28-37. [PMID: 11828196 DOI: 10.1111/j.1520-037x.2001.90810.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The endothelium is a diaphanous membrane, only one cell layer thick, that lines all of our blood vessels. Despite its apparent fragility, it exerts profound control over vascular tone, structure, and intersection with circulating blood elements. One of the factors that the endothelium synthesizes is nitric oxide, which is the most potent endogenous vasodilator known. In addition to its blood flow regulating effects, nitric oxide also inhibits key processes in atherosclerosis, including monocyte adherence, platelet aggregation, and proliferation of vascular smooth muscle cells. Nitric oxide synthesis is impaired, and its degradation is accelerated, in many of the conditions associated with atherosclerosis, including hypercholesterolemia. Restoration of nitric oxide synthesis and activity in these disorders can improve blood flow, relieve symptoms, and perhaps reduce the progression of atherosclerosis.(c) 2001 by CHF, Inc.
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Affiliation(s)
- L W Lissin
- Division of Cardiovascular Medicine, Stanford University Medical Center, Stanford, CA
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Das UN. Estrogen, statins, and polyunsaturated fatty acids: similarities in their actions and benefits-is there a common link? Nutrition 2002; 18:178-88. [PMID: 11844650 DOI: 10.1016/s0899-9007(01)00719-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVES To investigate whether there is any common link between estrogen, statins, and polyunsaturated fatty acids (PUFAs), which have similar actions and benefits. METHODS To critically review the literature pertaining to the actions of estrogen, statins, and various PUFAs. RESULTS Estrogen, statins, and PUFAs enhance nitric oxide synthesis, suppress the production of proinflammatory cytokines such as tumor necrosis factor(alpha), interleukin-1, interleukin-2, and interleukin-6, show antioxidant-like and antiatherosclerotic properties, have neuroprotective actions, and by themselves or their products inhibit tumor cell proliferation and improve osteoporosis. Estrogen, statins, and PUFAs not only have similar actions but also appear to interact with each other. For instance, the binding of estrogen to its receptor on the cell membrane may be determined by its lipid content, statins and PUFAs inhibit 3-hydroxy-3-methylglutaryl coenzyme A reductase activity, statins influence the metabolism of PUFAs, and PUFA deficiency enhances 3-hydroxy-3-methylglutaryl coenzyme A reductase activity. Statins and PUFAs inhibit tumor cell proliferation, suppress ras activity, and may prevent neurodegeneration and improve cognitive functions such as learning and memory. This suggests that PUFAs might be mediators of the actions of statins. Estrogen boosts cognitive performance in women after menopause and may protect against Alzheimer's disease. CONCLUSIONS The common link between estrogen, statins, and PUFAs may be nitric oxide. Hence, a combination(s) of estrogen or its derivatives, statins, and various PUFAs may form a novel approach in the management of various conditions such as hyperlipidemias, coronary heart disease, atherosclerosis, osteoporosis, cancer, neurodegenerative conditions, and to improve memory.
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Affiliation(s)
- U N Das
- EFA Sciences LLC, Norwood, Massachusetts 02062, USA.
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Schwertz DW, Penckofer S. Sex differences and the effects of sex hormones on hemostasis and vascular reactivity. Heart Lung 2001; 30:401-26; quiz 427-8. [PMID: 11723446 DOI: 10.1067/mhl.2001.118764] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Thrombus formation and vasospasm are involved in the initiation of acute ischemic events in the heart. Gender differences in persons with coronary artery disease and the incidence of myocardial ischemia have been clearly documented. In addition, it is well established that sex hormones influence the risk of developing coronary artery disease. Epidemiologic studies suggest that estrogen may exert a protective effect, yet the results of recently completed and ongoing prospective trials of estrogen and hormone (estrogen + progesterone) replacement suggest that these hormones can increase thrombotic events in postmenopausal women. This review focuses on sex (gender) differences in hemostasis and vascular reactivity and on the influence that sex hormones have on these physiologic systems. This review takes the novel approach of focusing on sex differences in hemostasis and vascular reactivity in healthy premenopausal women and men of a similar age. By comparing men and women in this age group, the confounding issues of age, pathology, or decline in sex hormone levels are avoided. Animal and in vitro investigations pertinent to examining potential cellular mechanism(s) of sex hormones in mediating these sex differences are discussed. We assume there is a relationship between the normal physiologic and pathologic effects of sex hormones; elucidating sex differences in normal cardiovascular function will help clarify the basis for sex differences in the incidence and manifestations of coronary heart disease and will aid in the future development of gender-specific therapies for cardiovascular disease.
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Affiliation(s)
- D W Schwertz
- College of Nursing, University of Illinois, Chicago, 60612, USA
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Abstract
OBJECTIVES To review the available information on the action of hormones on the mechanisms involved in thrombotic risk. RESULTS AND CONCLUSIONS Thrombosis plays a crucial role in the genesis and progression of both coronary heart disease (CHD) and venous thromboembolic disease (VTED), the two main forms of cardiovascular disease. Two main determinants of the thromboembolic phenotype, hypercoagulable state and altered endothelium, accumulate much of the work performed on the influence of hormones on thrombosis. Information has accumulated mainly for oestrogens, but increasing evidences support a role for progestogens. The sensitivity of each of the three components of the hemostatic balance, the coagulation cascade, the anticoagulant system and fibrinolysis, to oestrogens has been widely examined in the literature. Functional tests suggest that HRT is accompanied by a procoagulant state. Much of the work has concentrated on changes induced on reputable indicators of risk for either CHD or VTED. Distinct indicators of increased coagulability, such as resistance to activated C protein, antithrombin or tissue factor pathway inhibitor have been selected for VTED, whereas factor VII, fibrinogen, and defective fibrinolysis, for CHD. Different states of genetic susceptibility have been involved in both forms of the disease. The status of health of endothelium, defines another scenario for attention in CHD. A long-term anti-atherogenic action of oestrogens, which may be associated with short-term risk in cases of atherosclerosis-induced endothelial dysfunction, may most adequately explain much of the clinical observation. In both CHD and VTED, the procoagulant changes initiate soon after HRT administration.
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Affiliation(s)
- A Cano
- Department of Pediatrics, Obstetrics and Gynecology, Faculty of Medicine and Dentistry, University of Valencia, Avda. Blasco Ibañez, 17, E 46010 Valencia, Spain.
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