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1.
Pharmacol Res Perspect ; 10(5): e00995, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36065843

RESUMO

Aldosterone exerts some of its effects not by binding to mineralocorticoid receptors, but rather by acting via G protein-coupled estrogen receptors (GPER). To determine if aldosterone binds directly to GPER, we studied the ability of aldosterone to compete for the binding of [3 H] 2-methoxyestradiol ([3 H] 2-ME), a high potency GPER-selective agonist. We used GPER gene transfer to engineer Sf9-cultured insect cells to express GPER. We chose insect cells to avoid interactions with any intrinsic mammalian receptors for aldosterone. [3 H] 2-ME binding was saturable and reversible to a high-affinity population of receptors with Kd  = 3.7 nM and Bmax  = 2.2 pmol/mg. Consistent with agonist binding to G Protein-coupled receptors, [3 H] 2-ME high-affinity state binding was reduced in the presence of the hydrolysis-resistant GTP analog, GppNHp. [3 H] 2-ME binding was competed for by the GPER agonist G1, the GPER antagonist G15, estradiol (E2), as well as aldosterone (Aldo). The order of potency for competing for [3 H] 2-ME binding, namely 2ME > Aldo > E2 ≥ G1, paralleled the orders of potency for inhibition of cell proliferation and inhibition of ERK phosphorylation by ligands acting at GPER. These data confirm the ability of aldosterone to interact with the GPER, consistent with the interpretation that aldosterone likely mediates its GPER-dependent effects by direct binding to the GPER. SIGNIFICANCE STATEMENT: Despite the growing evidence for aldosterone's actions via G protein-coupled estrogen receptors (GPER), there remains significant skepticism that aldosterone can directly interact with GPER. The current studies are the first to demonstrate directly that aldosterone indeed is capable of binding to the GPER and thus likely mediates its GPER-dependent effects by direct binding to the receptor.


Assuntos
Aldosterona , Receptores de Estrogênio , Aldosterona/metabolismo , Animais , Estrogênios , Proteínas de Ligação ao GTP/metabolismo , Mamíferos/metabolismo , Mercaptoetanol , Receptores Acoplados a Proteínas G/metabolismo
2.
Br J Clin Pharmacol ; 87(4): 1801-1813, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32986870

RESUMO

AIMS: Aldosterone has been found to influence cancer cell growth, cell cycle regulation and cell migration, including in prostate cancer cells. Spironolactone is an aldosterone antagonist used for managing chronic heart failure (HF) with known antiandrogenic effects. We examined the effect of spironolactone exposure amongst men with HF on the incidence of prostate cancer. METHODS: This retrospective cohort study utilized provincial clinical and administrative databases from the Manitoba Centre for Health Policy. Incident cases of prostate cancer were identified from the provincial cancer registry, and spironolactone exposure was quantified from pharmacare databases. A multivariable proportional hazards model was used to assess the time-dependent impact of spironolactone exposure on prostate cancer incidence. RESULTS: A total of 18 562 men with newly diagnosed HF from 2007 to 2015 with a median age of 72 years (interquartile range: 61-81) and a median follow-up from HF diagnosis to prostate cancer incidence of 2.7 years (interquartile range: 1.1-4.9) were included. A time-dependent multivariable analysis of spironolactone exposure following HF diagnosis found a reduced the risk of prostate cancer hazard ratio 0.55 (95% confidence interval 0.31-0.98, P = .043). CONCLUSION: Spironolactone exposure significantly reduced the incidence of prostate cancer amongst men with HF. These findings support the plausibility of aldosterone as a promoter of prostate cancer growth and development. Prospective clinical trials are warranted to further assess the role of spironolactone or other mineralocorticoid receptor antagonists as a means to prevent prostate cancer development or as an adjunctive measure to prostate cancer treatments.


Assuntos
Insuficiência Cardíaca , Neoplasias da Próstata , Idoso , Idoso de 80 Anos ou mais , Insuficiência Cardíaca/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/efeitos adversos , Estudos Prospectivos , Neoplasias da Próstata/epidemiologia , Estudos Retrospectivos , Espironolactona/efeitos adversos , Resultado do Tratamento
3.
Can J Cardiol ; 36(5): 706-711, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32389343

RESUMO

The way we view coronary artery disease in women has changed dramatically over the past decades. From an initial perspective that coronary artery disease was a male disorder and that women were protected by estrogens, there has been the gradual appreciation that this is an equal opportunity disease. Postmenopausal women are more likely than men to be hypertensive, dyslipidemic, and have multiple risk factors. Beyond the appreciation of estrogen's global effects on cardiovascular and metabolic function, our further advances in the understanding of sex-specific risks and management will be based on a greater understanding of the diversity of estrogen-mediated receptor pathways, including appreciation of the sometimes divergent effects of estrogen when acting either via the classic estrogen receptor or the more recently appreciated G protein-coupled estrogen receptor. In addition, the importance of sex-specific regulation of cardiometabolic processes beyond the sex hormones, specifically via SRY regulation, is only beginning to be understood. Finally, the author summarizes his recent studies demonstrating sex-specific G protein-coupled estrogen receptor regulation of blood pressure and cholesterol metabolism that may serve as a paradigm for the elucidation of sex-specific determinants of cardiovascular risk and the basis for sex-specific management of those risks.


Assuntos
Aterosclerose/genética , Doença da Artéria Coronariana/genética , Aterosclerose/fisiopatologia , Pressão Sanguínea/genética , Pressão Sanguínea/fisiologia , Colesterol/metabolismo , Doença da Artéria Coronariana/fisiopatologia , Estrogênios/fisiologia , Humanos , Receptores de Estrogênio/genética , Receptores de Estrogênio/fisiologia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/fisiologia , Fatores de Risco , Cromossomos Sexuais/genética , Cromossomos Sexuais/fisiologia , Fatores Sexuais
6.
Can J Cardiol ; 33(5): 557-576, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28449828

RESUMO

Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, assessment, prevention, and treatment of hypertension. This year, we introduce 10 new guidelines. Three previous guidelines have been revised and 5 have been removed. Previous age and frailty distinctions have been removed as considerations for when to initiate antihypertensive therapy. In the presence of macrovascular target organ damage, or in those with independent cardiovascular risk factors, antihypertensive therapy should be considered for all individuals with elevated average systolic nonautomated office blood pressure (non-AOBP) readings ≥ 140 mm Hg. For individuals with diastolic hypertension (with or without systolic hypertension), fixed-dose single-pill combinations are now recommended as an initial treatment option. Preference is given to pills containing an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker in combination with either a calcium channel blocker or diuretic. Whenever a diuretic is selected as monotherapy, longer-acting agents are preferred. In patients with established ischemic heart disease, caution should be exercised in lowering diastolic non-AOBP to ≤ 60 mm Hg, especially in the presence of left ventricular hypertrophy. After a hemorrhagic stroke, in the first 24 hours, systolic non-AOBP lowering to < 140 mm Hg is not recommended. Finally, guidance is now provided for screening, initial diagnosis, assessment, and treatment of renovascular hypertension arising from fibromuscular dysplasia. The specific evidence and rationale underlying each of these guidelines are discussed.


Assuntos
Anti-Hipertensivos , Determinação da Pressão Arterial/métodos , Diuréticos , Hipertensão , Adulto , Anti-Hipertensivos/classificação , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Canadá/epidemiologia , Comorbidade , Diuréticos/classificação , Diuréticos/uso terapêutico , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/prevenção & controle , Masculino , Conduta do Tratamento Medicamentoso/normas , Pessoa de Meia-Idade , Medição de Risco/métodos
7.
Annu Rev Pharmacol Toxicol ; 57: 567-584, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-27814026

RESUMO

Although the rapid effects of steroids, such as estrogen and aldosterone, were postulated originally to be nongenomic, it is now appreciated that activation of such signaling pathways via a steroid-acting G protein-coupled receptor, the G protein estrogen receptor (GPER), has important transcription-dependent outcomes in the regulation of cell growth and programmed cell death secondary to GPER-regulated second-messenger pathways. GPER is expressed ubiquitously and has diverse biological effects, including regulation of endocrine, immune, neuronal, and cardiovascular functions. Perhaps the most biologically important consequences of GPER activation are the regulation of cell growth, migration, and apoptotic cell death. These cell growth regulatory effects, important in cancer biology, are also relevant in the regulation of cardiac and vascular hypertrophy and in the response to ischemia. This review provides a summary of relevant findings of the impact of GPER regulation by either estradiol or aldosterone in in vitro model systems and extends those findings to in vivo studies of direct clinical relevance for development of GPER-directed agents for treatment of cancer and cardiovascular diseases associated with cellular proliferation.


Assuntos
Aldosterona/metabolismo , Doenças Cardiovasculares/metabolismo , Estradiol/metabolismo , Neoplasias/metabolismo , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Aldosterona/farmacologia , Aldosterona/uso terapêutico , Animais , Doenças Cardiovasculares/tratamento farmacológico , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Estradiol/farmacologia , Estradiol/uso terapêutico , Hormônios Esteroides Gonadais/metabolismo , Hormônios Esteroides Gonadais/farmacologia , Hormônios Esteroides Gonadais/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico
8.
Hypertension ; 68(5): 1225-1235, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27698063

RESUMO

Estrogens are important regulators of cardiovascular function. Some of estrogen's cardiovascular effects are mediated by a G-protein-coupled receptor mechanism, namely, G-protein-coupled estrogen receptor (GPER). Estradiol-mediated regulation of vascular cell programmed cell death reflects the balance of the opposing actions of GPER versus estrogen receptor α (ERα). However, the significance of these opposing actions on the regulation of vascular smooth muscle cell proliferation or migration in vitro is unclear, and the significance in vivo is unknown. To determine the effects of GPER activation in vitro, we studied rat aortic vascular smooth muscle cells maintained in primary culture. GPER was reintroduced using adenoviral gene transfer. Both estradiol and G1, a GPER agonist, inhibited both proliferation and cell migration effects that were blocked by the GPER antagonist, G15. To determine the importance of the GPER-ERα balance in regulating vascular remodeling in a rat model of carotid ligation, we studied the effects of upregulation of GPER expression versus downregulation of ERα. Reintroduction of GPER significantly attenuated the extent of medial hypertrophy and attenuated the extent of CD45 labeling. Downregulation of ERα expression comparably attenuated the extent of medial hypertrophy and inflammation after carotid ligation. These studies demonstrate that the balance between GPER and ERα regulates vascular remodeling. Receptor-specific modulation of estrogen's effects may be an important new approach in modifying vascular remodeling in both acute settings like vascular injury and perhaps in longer term regulation like in hypertension.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Regulação da Expressão Gênica , Músculo Liso Vascular/crescimento & desenvolvimento , Receptores Acoplados a Proteínas G/genética , Remodelação Vascular/genética , Análise de Variância , Animais , Artérias Carótidas/cirurgia , Movimento Celular/genética , Proliferação de Células/genética , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Ligadura/métodos , Masculino , Músculo Liso Vascular/citologia , Valor Preditivo dos Testes , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Wistar , Regulação para Cima
9.
Int J Mol Sci ; 17(5)2016 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-27213340

RESUMO

Heart disease in women remains underappreciated, underdiagnosed and undertreated. Further, although we are starting to understand some of the social and behavioral determinants for this, the biological basis for the increased rate of rise in atherosclerosis risk in women after menopause remains very poorly understand. In this review we will outline the scope of the clinical issues related to heart disease in women, the emerging findings regarding the biological basis underlying the increased prevalence of atherosclerotic risk factors in postmenopausal women (vs. men) and the role of the G protein-coupled estrogen receptor (GPER) and its genetic regulation as a determinant of these sex-specific risks. GPER is a recently appreciated GPCR that mediates the rapid effects of estrogen and aldosterone. Recent studies have identified that GPER activation regulates both blood pressure. We have shown that regulation of GPER function via expression of a hypofunctional GPER genetic variant is an important determinant of blood pressure and risk of hypertension in women. Further, our most recent studies have identified that GPER activation is an important regulator of low density lipoprotein (LDL) receptor metabolism and that expression of the hypofunctional GPER genetic variant is an important contributor to the development of hypercholesterolemia in women. GPER appears to be an important determinant of the two major risk factors for coronary artery disease-blood pressure and LDL cholesterol. Further, the importance of this mechanism appears to be greater in women. Thus, the appreciation of the role of GPER function as a determinant of the progression of atherosclerotic disease may be important both in our understanding of cardiometabolic function but also in opening the way to greater appreciation of the sex-specific regulation of atherosclerotic risk factors.


Assuntos
Cardiopatias/genética , Cardiopatias/patologia , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/genética , Feminino , Regulação da Expressão Gênica , Predisposição Genética para Doença , Cardiopatias/tratamento farmacológico , Cardiopatias/metabolismo , Humanos , Hipertensão/genética , Terapia de Alvo Molecular , Pós-Menopausa , Receptores de Estrogênio/antagonistas & inibidores , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de LDL/metabolismo , Fatores de Risco
10.
FASEB J ; 30(6): 2086-96, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26911792

RESUMO

Although aldosterone is a known regulator of renal and cardiovascular function, its role as a regulator of cancer growth and spread has not been widely considered. This study tested the hypothesis that aldosterone regulates cancer cell growth/spread via G protein-coupled estrogen receptor (GPER) activation. In vitro in murine renal cortical adenocarcinoma (RENCA) cells, a widely used murine in vitro model for the study of renal cell adenocarcinoma, aldosterone increased RENCA cell proliferation to a maximum of 125 ± 3% of control at a concentration of 10 nM, an effect blocked by the GPER antagonist G15 or by GPER knockdown using short interfering (sh) RNA techniques. Further, aldosterone increased RENCA cell migration to a maximum of 170 ± 20% of control at a concentration of 100 nM, an effect also blocked by G15 or by GPER down-regulation. In vivo, after orthotopic RENCA cell renal transplantation, pulmonary tumor spread was inhibited by pharmacologic blockade of aldosterone effects with spironolactone (percentage of lung occupied by metastasis: control = 68 ± 13, spironolactone = 26 ± 8, P < 0.05) or inhibition of aldosterone synthesis with a high dietary salt diet (percentage of lung: control = 44 ± 6, high salt = 12 ± 3, P < 0.05), without reducing primary tumor size. Additionally, adrenalectomy significantly reduced the extent of pulmonary tumor spread, whereas aldosterone infusion recovered pulmonary metastatic spread toward baseline levels. Finally, inhibition of GPER either with the GPER antagonist G15 or by GPER knockdown comparably inhibited RENCA cell pulmonary metastatic cancer spread. Taken together, these findings provide strong evidence for aldosterone serving a causal role in renal cell cancer regulation via its GPER receptor; thus, antagonism of GPER represents a potential new target for treatment to reduce metastatic spread.-Feldman, R. D., Ding, Q., Hussain, Y., Limbird, L. E., Pickering, J. G., Gros, R. Aldosterone mediates metastatic spread of renal cancer via the G protein-coupled estrogen receptor (GPER).


Assuntos
Aldosterona/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Renais/metabolismo , Metástase Neoplásica/fisiopatologia , Neoplasias Experimentais/metabolismo , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Aldosterona/genética , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Neoplasias Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Interferência de RNA , RNA Interferente Pequeno , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/genética , Espironolactona/farmacologia
11.
Trends Endocrinol Metab ; 26(11): 592-594, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26482875

RESUMO

Whether aldosterone activates the G-protein-coupled estrogen receptor (GPER) has been questioned, recently, in the name of Copernicus. However, for G-protein-coupled receptors (GPCRs) multiple hormone activators are common. Further, studies in mineralocorticoid receptor (MR)-deficient systems, with pharmacological GPER-selective antagonists or regulation of GPER expression, consistently show that some aldosterone effects can be GPER mediated.


Assuntos
Aldosterona/metabolismo , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Humanos
12.
Can J Cardiol ; 31(5): 549-68, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25936483

RESUMO

The Canadian Hypertension Education Program reviews the hypertension literature annually and provides detailed recommendations regarding hypertension diagnosis, assessment, prevention, and treatment. This report provides the updated evidence-based recommendations for 2015. This year, 4 new recommendations were added and 2 existing recommendations were modified. A revised algorithm for the diagnosis of hypertension is presented. Two major changes are proposed: (1) measurement using validated electronic (oscillometric) upper arm devices is preferred over auscultation for accurate office blood pressure measurement; (2) if the visit 1 mean blood pressure is increased but < 180/110 mm Hg, out-of-office blood pressure measurements using ambulatory blood pressure monitoring (preferably) or home blood pressure monitoring should be performed before visit 2 to rule out white coat hypertension, for which pharmacologic treatment is not recommended. A standardized ambulatory blood pressure monitoring protocol and an update on automated office blood pressure are also presented. Several other recommendations on accurate measurement of blood pressure and criteria for diagnosis of hypertension have been reorganized. Two other new recommendations refer to smoking cessation: (1) tobacco use status should be updated regularly and advice to quit smoking should be provided; and (2) advice in combination with pharmacotherapy for smoking cessation should be offered to all smokers. The following recommendations were modified: (1) renal artery stenosis should be primarily managed medically; and (2) renal artery angioplasty and stenting could be considered for patients with renal artery stenosis and complicated, uncontrolled hypertension. The rationale for these recommendation changes is discussed.


Assuntos
Determinação da Pressão Arterial/normas , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Guias de Prática Clínica como Assunto , Prevenção Primária/normas , Anti-Hipertensivos/uso terapêutico , Monitorização Ambulatorial da Pressão Arterial/normas , Canadá , Educação Médica Continuada/normas , Feminino , Humanos , Hipertensão/prevenção & controle , Masculino , Medição de Risco
13.
Arterioscler Thromb Vasc Biol ; 35(1): 213-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25395619

RESUMO

OBJECTIVE: Estrogen deficiency is linked with increased low-density lipoprotein (LDL) cholesterol. The hormone receptor mediating this effect is unknown. G-protein estrogen receptor (GPER) is a recently recognized G-protein-coupled receptor that is activated by estrogens. We recently identified a common hypofunctional missense variant of GPER, namely P16L. However, the role of GPER in LDL metabolism is unknown. Therefore, we examined the association of the P16L genotype with plasma LDL cholesterol level. Furthermore, we studied the role of GPER in regulating expression of the LDL receptor and proprotein convertase subtilisin kexin type 9. APPROACH AND RESULTS: Our discovery cohort was a genetically isolated population of Northern European descent, and our validation cohort consisted of normal, healthy women aged 18 to 56 years from London, Ontario. In addition, we examined the effect of GPER on the regulation of proprotein convertase subtilisin kexin type 9 and LDL receptor expression by the treatment with the GPER agonist, G1. In the discovery cohort, GPER P16L genotype was associated with a significant increase in LDL cholesterol (mean±SEM): 3.18±0.05, 3.25±0.08, and 4.25±0.33 mmol/L, respectively, in subjects with CC (homozygous for P16), CT (heterozygotes), and TT (homozygous for L16) genotypes (P<0.05). In the validation cohort (n=339), the GPER P16L genotype was associated with a similar increase in LDL cholesterol: 2.17±0.05, 2.34±0.06, and 2.42±0.16 mmol/L, respectively, in subjects with CC, CT, and TT genotypes (P<0.05). In the human hepatic carcinoma cell line, the GPER agonist, G1, mediated a concentration-dependent increase in LDL receptor expression, blocked by either pretreatment with the GPER antagonist G15 or by shRNA-mediated GPER downregulation. G1 also mediated a GPER- and concentration-dependent decrease in proprotein convertase subtilisin kexin type 9 expression. CONCLUSIONS: GPER activation upregulates LDL receptor expression, probably at least, in part, via proprotein convertase subtilisin kexin type 9 downregulation. Furthermore, humans carrying the hypofunctional P16L genetic variant of GPER have increased plasma LDL cholesterol. In aggregate, these data suggest an important role of GPER in the regulation of LDL receptor expression and consequently LDL metabolism.


Assuntos
LDL-Colesterol/sangue , Mutação de Sentido Incorreto , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Adolescente , Adulto , Idoso , Canadá , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica , Frequência do Gene , Genética Populacional , Células Hep G2 , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/metabolismo , Interferência de RNA , Receptores de Estrogênio/efeitos dos fármacos , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores de LDL/genética , Receptores de LDL/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Transfecção , População Branca/genética , Adulto Jovem
14.
Br J Clin Pharmacol ; 78(6): 1441-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25039431

RESUMO

AIMS: Activation of vascular GPER has been linked to vasodepressor effects in animals. However, the significance of GPER regulation on chronic blood pressure control in humans is unknown. METHODS: To examine this question we determined the functional significance of expression of a common missense single nucleotide variant of GPER, P16L in vascular smooth muscle cells, and its association with blood pressure in humans. Further, to validate the importance of carrying GPER P16L in the development of hypertension we assessed allele frequency in a cohort of hard-to-treat hypertensive patients referred to a tertiary care clinic. RESULTS: Expression of the GPER P16L variant (V) vs. wild type (WT) in rat aortic vascular smooth muscle cells, was associated with a significant decrease in G1 (1 µm, a GPER agonist)-mediated ERK phosphorylation (slope of the function of G1-stimulated ERK phosphorylation: GPER content WT: 16.2, 95% CI 9.9, 22.6; V: 5.0, 95% CI 1.0, 9.0; P < 0.005) and apoptosis (slope of the function of G1-stimulated apoptosis: GPER content: WT: 4.4, 95% CI: 3.4, 5.4; V: 2.5, 95% CI 1.6, 2.3 P < 0.005). Normotensive female subjects, but not male subjects, carrying this hypofunctional variant (allele frequency 22%) have increased blood pressure [mean arterial pressure: P16/P16: 80 ± 1 mmHg (n = 204) vs. P16L carriers: 82 ± 1 mmHg (n = 127), 95% CI for difference: 0.6, 4.0 mmHg, P < 0.05], [systolic blood pressure: P16/P16: 105 ± 1 mmHg vs. P16L carriers: 108 ± 1 mmHg, 95% CI for difference:1.0, 5.1 mmHg, P < 0.05], [diastolic blood pressure: P16/P16: 66 ± 0.5 mmHg vs. P16L carriers 68 ± 0.7, 95% CI for difference: 0.2, 3.6 mmHg, P < 0.05]. Further, the P16L allele frequency was almost two-fold higher in female vs. male hypertensive patients (31% vs. 16%, allele ratio 0.5, 95% CI 0.32, 0.76, P < 0.05). CONCLUSIONS: The common genetic variant, GPER P16L, is hypofunctional and female carriers of this allele have increased blood pressure. There was an increased prevalence in a population of hard-to-treat hypertensive female patients. Cumulatively, these data suggest that in females, impaired GPER function might be associated with increased blood pressure and risk of hypertension.


Assuntos
Hipertensão/genética , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/genética , Adolescente , Adulto , Animais , Apoptose , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Frequência do Gene , Variação Genética , Humanos , Hipertensão/etiologia , Masculino , Fosforilação , Ratos , Caracteres Sexuais
15.
Can J Cardiol ; 30(5): 517-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24786441

RESUMO

The polypill concept for atherosclerosis is based on the notion that a single pill containing multiple products that attack frequently encountered risk factors will provide important advantages as a preventive strategy, particularly in the developing world. Potential benefits include improved efficacy and greater compliance because of simplicity and reduced costs. Here, we briefly review the rationale for the polypill and the evidence supporting its value. We consider the polypill to be a major advance in combat against cardiovascular disease, with enormous benefits to global health to be expected from its use.


Assuntos
Anti-Hipertensivos/administração & dosagem , Hipertensão/tratamento farmacológico , Adesão à Medicação , Padrões de Prática Médica , Humanos
17.
Clin Exp Pharmacol Physiol ; 40(12): 916-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23902478

RESUMO

Aldosterone has actions far beyond its role as a renal regulator of sodium reabsorption, and broader mechanisms of action than simply a transcriptional regulator. Aldosterone has a number of vascular effects, including regulation of vascular reactivity and vascular growth and/or development. Aldosterone-mediated effects on vascular reactivity reflect a balance between its endothelial-dependent vasodilator effects and its direct smooth muscle vasoconstrictor effects. The endothelial vasodilator effects of aldosterone are mediated by phosphatidylinositol 3-kinase-dependent activation of nitric oxide synthase. G-Protein oestrogen receptor (GPER) is a recently recognized G-protein coupled receptor (GPCR) that is activated by steroid hormones. It was first recognized as the GPCR mediating the rapid effects of oestrogens. Activation of GPER also mediates at least some of the vascular effects of aldosterone in smooth muscle and endothelial cells. In vascular endothelial cells, aldosterone activation of GPER mediates vasodilation. In contrast, activation of endothelial mineralocorticoid receptors has been linked to enhanced vasoconstrictor and/or impaired vasodilator responses.


Assuntos
Aldosterona/fisiologia , Endotélio Vascular/metabolismo , Músculo Liso Vascular/metabolismo , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Mineralocorticoides/metabolismo , Aldosterona/metabolismo , Endotélio Vascular/fisiopatologia , Humanos , Ligantes , Músculo Liso Vascular/fisiopatologia , Vasoconstrição/fisiologia , Vasodilatação/fisiologia
18.
Am J Physiol Cell Physiol ; 304(6): C532-40, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23283935

RESUMO

The importance of the rapid vascular effects of aldosterone is increasingly appreciated. Through these rapid pathways, aldosterone has been shown to regulate vascular contractility, cell growth, and apoptosis. In our most recent studies, we demonstrated the effects of aldosterone on cell growth and contractility in vascular smooth muscle cells. We showed that these effects could occur via activation of the classic mineralocorticoid receptor, as well the recently characterized G protein-coupled estrogen receptor (GPER), initially characterized as an estrogen-specific receptor. However, the mechanisms underlying aldosterone's endothelium-dependent actions are unknown. Furthermore, the ERK regulatory and proapoptotic effects of aldosterone mediated by GPER activation in cultured vascular smooth muscle cells were only apparent when GPER was reintroduced into these cells by gene transfer. Whether GPER activation via aldosterone might be an important regulator in native vascular cells has been questioned. Therefore, to determine the role of GPER in mediating aldosterone's effects on cell growth and vascular reactivity in native cells, we examined rat aortic vascular endothelial cells, a model characterized by persistent robust expression of GPER, but without detectable mineralocorticoid receptor expression. In these endothelial cells, the GPER agonist G1 mediates a rapid increase in ERK phosphorylation that is wholly GPER-dependent, paralleling the actions of aldosterone. The effects of G1 and aldosterone to stimulate ERK phosphorylation paralleled their proapoptotic and antiproliferative effects. In previous studies, we reported that aldosterone mediates a rapid endothelium-dependent vasodilatory effect, antagonistic to its direct vasoconstrictor effect in endothelium-denuded preparations. Using a rat aortic ring/organ bath preparation to determine the GPER dependence of aldosterone's endothelium-dependent vasodilator effects, we demonstrate that aldosterone inhibits phenylephrine-mediated contraction. This vasodilator effect parallels the actions of the GPER agonist G1. Furthermore, the effects of aldosterone were completely ablated by the GPER antagonist G15. These data support an important role of GPER activation in aldosterone-mediated regulation of endothelial cell growth, as well as in aldosterone's endothelium-mediated regulation of vasoreactivity.


Assuntos
Aldosterona/metabolismo , Células Endoteliais/fisiologia , Músculo Liso Vascular/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Mineralocorticoides/metabolismo , Animais , Aorta/metabolismo , Aorta/fisiologia , Apoptose/efeitos dos fármacos , Cardiotônicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Fatores Relaxantes Dependentes do Endotélio/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Técnicas de Transferência de Genes , Antagonistas de Receptores de Mineralocorticoides , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Fenilefrina/farmacologia , Fosforilação , Ratos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/efeitos dos fármacos , Vasoconstrição/fisiologia , Vasoconstritores/farmacologia , Vasodilatação/fisiologia
19.
Naunyn Schmiedebergs Arch Pharmacol ; 385(1): 5-12, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22012074

RESUMO

Adenylyl cyclases are a ubiquitous family of enzymes and are critical regulators of metabolic and cardiovascular function. Multiple isoforms of the enzyme are expressed in a range of tissues. However, for many processes, the adenylyl cyclase isoforms have been thought of as essentially interchangeable, with their impact more dependent on their common actions to increase intracellular cyclic adenosine monophosphate content regardless of the isoform involved. It has long been appreciated that each subfamily of isoforms demonstrate a specific pattern of "upstream" regulation, i.e., specific patterns of ion dependence (e.g., calcium-dependence) and specific patterns of regulation by kinases (protein kinase A (PKA), protein kinase C (PKC), raf). However, more recent studies have suggested that adenylyl cyclase isoform-selective patterns of signaling are a wide-spread phenomenon. The determinants of these selective signaling patterns relate to a number of factors, including: (1) selective coupling of specific adenylyl cyclase isoforms with specific G protein-coupled receptors, (2) localization of specific adenylyl cyclase isoforms in defined structural domains (AKAP complexes, caveolin/lipid rafts), and (3) selective coupling of adenylyl cyclase isoforms with specific downstream signaling cascades important in regulation of cell growth and contractility. The importance of isoform-specific regulation has now been demonstrated both in mouse models as well as in humans. Adenylyl cyclase has not been viewed as a useful target for therapeutic regulation, given the ubiquitous expression of the enzyme and the perceived high risk of off-target effects. Understanding which isoforms of adenylyl cyclase mediate distinct cellular effects would bring new significance to the development of isoform-specific ligands to regulate discrete cellular actions.


Assuntos
Adenilil Ciclases/metabolismo , Animais , Humanos , Isoenzimas , Transdução de Sinais
20.
Can J Cardiol ; 27(4): 415-433.e1-2, 2011.
Artigo em Inglês, Francês | MEDLINE | ID: mdl-21801975

RESUMO

We updated the evidence-based recommendations for the diagnosis, assessment, prevention, and treatment of hypertension in adults for 2011. The major guideline changes this year are: (1) a recommendation was made for using comparative risk analogies when communicating a patient's cardiovascular risk; (2) diagnostic testing issues for renal artery stenosis were discussed; (3) recommendations were added for the management of hypertension during the acute phase of stroke; (4) people with hypertension and diabetes are now considered high risk for cardiovascular events if they have elevated urinary albumin excretion, overt kidney disease, cardiovascular disease, or the presence of other cardiovascular risk factors; (5) the combination of an angiotensin-converting enzyme (ACE) inhibitor and a dihydropyridine calcium channel blocker (CCB) is preferred over the combination of an ACE inhibitor and a thiazide diuretic in persons with diabetes and hypertension; and (6) a recommendation was made to coordinate with pharmacists to improve antihypertensive medication adherence. We also discussed the recent analyses that examined the association between angiotensin II receptor blockers (ARBs) and cancer.


Assuntos
Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Adulto , Anti-Hipertensivos/uso terapêutico , Determinação da Pressão Arterial , Canadá , Educação em Saúde , Humanos , Medição de Risco
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