145 research outputs found
Effects of Estrogen on vascular inflammation: a matter of timing.
Objective: Our study aims to determine the role of time of menopause on vascular inflammation biomarkers and how it affects their modulation by estrogen and raloxifene in postmenopausal women. Methods and results: Uterine arteries from 68 postmenopausal women were divided into 3 segments and cultured for 24 hours in tissue culture media containing 17β-estradiol (100 nmol/L), raloxifene (100 nmol/L), or vehicle. Assessment of arterial concentration of 13 inflammatory biomarkers was performed by multiplex immunobead-based assay. Aging per se has a positive correlation with the generation of several proinflammatory markers. Although short-term estradiol exposure correlates with lower expression of tumor necrosis factor-α, vascular endothelial growth factor, and interleukin-1β in all age groups, for most biomarkers aging was associated with a switch from a beneficial anti-inflammatory action by estrogen, at earlier stages of menopause, to a proinflammatory profile after 5 years past its onset. Raloxifene has no significant effect on the expression of all proinflammatory markers. Western blot analysis of estrogen receptor expression (estrogen receptor-α and estrogen receptor-β) showed that estrogen receptor-β increases with aging, and this increase has a positive correlation with the generation of several proinflammatory markers. Conclusions: Aging alters estrogen-mediated effects on the modulation of inflammatory biomarkers in women. How aging affects estrogen responses on vascular inflammation is not clear, but our data show a positive association between increased estrogen receptor-β expression with aging and proinflammatory effects by estrogen
Aging Negatively Affects Estrogens-Mediated Effects on Nitric Oxide Bioavailability by Shifting ERα/ERβ Balance in Female Mice
AIMS: Aging is among the major causes for the lack of cardiovascular protection by estrogen (E2) during postmenopause. Our study aims to determine the mechanisms whereby aging changes E2 effects on nitric oxide (NO) production in a mouse model of accelerated senescence (SAM). METHODS AND RESULTS: Although we found no differences on NO production in females SAM prone (SAMP, aged) compared to SAM resistant (SAMR, young), by either DAF-2 fluorescence or plasmatic nitrite/nitrate (NO2/NO3), in both cases, E2 treatment increased NO production in SAMR but had no effect in SAMP. Those results are in agreement with changes of eNOS protein and gene expression. E2 up-regulated eNOS expression in SAMR but not in SAMP. E2 is also known to increase NO by decreasing its catabolism by superoxide anion (O(2)(-)). Interestingly, E2 treatment decreased O(2)(-) production in young females, while increased O(2)(-) in aged ones. Furthermore, we observed that aging changed expression ratio of estrogen receptors (ERβ/ERα) and levels of DNA methylation. Increased ratio ERβ/ERα in aged females is associated to a lack of estrogen modulation of NO production and with a reversal in its antioxidant effect to a pro-oxidant profile. CONCLUSIONS: Together, our data suggest that aging has detrimental effects on E2-mediated benefits on NO bioavailability, partially by affecting the ability of E2 to induce up regulation of eNOS and decrease of O(2)(-). These modifications may be associated to aging-mediated modifications on global DNA methylation status, but not to a specific methylation at 5'flanking region of ERα gene
An affordable method to obtain cultured endothelial cells from peripheral blood
The culture of endothelial progenitor cells (EPC) provides an excellent tool to research on EPC biology and vascular regeneration and vasculogenesis. The use of different protocols to obtain EPC cultures makes it difficult to obtain comparable results in different groups. This work offers a systematic comparison of the main variables of most commonly used protocols for EPC isolation, culture and functional evaluation. Peripheral blood samples from healthy individuals were recovered and mononuclear cells were cultured. Different recovery and culture conditions were tested: blood volume, blood anticoagulant, coating matrix and percentage of foetal bovine serum (FBS) in culture media. The success of culture procedure, first colonies of endothelial cells appearance time, correlation with number of circulating EPC (cEPC) and functional comparison with human umbilical vein endothelial cells (HUVEC) were studied. The use of heparin, a minimum blood volume of 30 ml, fibronectin as a coating matrix and endothelial growing media-2 supplemented with 20% FBS increased the success of obtaining EPC cultures up to 80% of the processed samples while reducing EPC colony appearance mean time to a minimum of 13 days. Blood samples exhibiting higher cEPC numbers resulted in reduced EPC colony appearance mean time. Cells isolated by using this combination were endothelial cell-like EPCs morphological and phenotypically. Functionally, cultured EPC showed decreased growing and vasculogenic capacity when compared to HUVEC. Thus, above-mentioned conditions allow the isolation and culture of EPC with smaller blood volumes and shorter times than currently used protocols
Characterization of Ion Channels Involved in the Proliferative Response of Femoral Artery Smooth Muscle Cells
31 páginas, 6 figuras, adicionales 6 figuras y 3 tablas.[Objective]: Vascular smooth muscle cells (VSMCs) contribute significantly to occlusive vascular diseases by virtue of their ability to switch to a noncontractile, migratory, and proliferating phenotype. Although the participation of ion channels in this phenotypic modulation (PM) has been described previously, changes in their expression are poorly defined because of their large molecular diversity. We obtained a global portrait of ion channel expression in contractile versus proliferating mouse femoral artery VSMCs, and explored the functional contribution to the PM of the most relevant changes that we observed.
[Methods and Results]: High-throughput real-time polymerase chain reaction of 87 ion channel genes was performed in 2 experimental paradigms: an in vivo model of endoluminal lesion and an in vitro model of cultured VSMCs obtained from explants. mRNA expression changes showed a good correlation between the 2 proliferative models, with only 2 genes, Kv1.3 and Kvβ2, increasing their expression on proliferation. The functional characterization demonstrates that Kv1.3 currents increased in proliferating VSMC and that their selective blockade inhibits migration and proliferation.
[Conclusion]: These findings establish the involvement of Kv1.3 channels in the PM of VSMCs, providing a new therapeutical target for the treatment of intimal hyperplasia.This work was supported by Ministerio de Sanidad, Instituto de
Salud Carlos III grants R006/009 (Red Heracles), FS041139-0
(M.R.), and PI041044 (J.R.L.-L.); Ministerio de Educacio´n y
Ciencia grants BFU2004-05551 (M.T.P.-G.) and BFU2007-61524
(J.R.L.-L.); and Junta de Castilla y Leon grant GR242. Dr
Moreno-DomÃnguez is a fellow of the Spanish Ministerio de
Educacion y Ciencia.Peer reviewe
Aging enhances contraction to thromboxane A2 in aorta from female senescence mice
The time-course for aging-associated effects on vascular reactivity to U46619, a stable analogue of thromboxane A2 (TXA2), was studied in aorta from female senescence-accelerated mice-prone (SAMP8), a murine model of accelerated senescence. SAMP8 and senescence-accelerated mice-resistant (SAMR1) were divided into three groups: 3-, 6- and 10-month-old. Contractile curves to U46619 (10−9 to 10−6 M) were performed in aortic rings in the absence or in the presence of nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 10−4 M) and/or cyclooxygenase (COX) inhibitor indomethacin (10−5 M). Protein and gene expression for COX-1 and COX-2 were determined by immunofluorescence and real-time PCR, respectively. Maximal contraction to U46619 was markedly higher in SAMP8 at all ages. In SAMR1, increases were seen at 10 months, while SAMP8 displays augmented contraction at 6 months, which was further increased at 10 months. L-NAME enhanced U46619 contractions in both 6-month-old groups, although the increase was higher on vessels from SAMR1 at this age. Indomethacin equally increased U46619 contractions in both 3-month-old groups, suggesting the production of vasodilator prostaglandin in young animals. In contrast, at 6 and 10 months indomethacin decreased U46619 contractions in both groups, indicating an aging-associated swap to a release of contractile prostanoids in aorta. In conclusion, aging enhances contractile responses to TXA2 in aorta from female mice by a mechanism involving a decrease of NO production and increased action of contractile prostanoids. This process occurs earlier in SAMP8 mice, establishing these mice as good model to study cardiovascular aging in a convenient and standard time-course
Endothelial Progenitor Cells Predict Cardiovascular Events after Atherothrombotic Stroke and Acute Myocardial Infarction. A PROCELL Substudy
The aim of this study was to determine prognostic factors for the risk of new vascular events during the first 6 months after acute myocardial infarction (AMI) or atherothrombotic stroke (AS). We were interested in the prognostic role of endothelial progenitor cells (EPC) and circulating endothelial cells (CEC) Between February 2009 and July 2012, 100 AMI and 50 AS patients were consecutively studied in three Spanish centres. Patients with previously documented coronary artery disease or ischemic strokes were excluded. Samples were collected within 24h of onset of symptoms. EPC and CEC were studied using flow cytometry and categorized by quartiles. Patients were followed for up to 6 months. NVE was defined as new acute coronary syndrome, transient ischemic attack (TIA), stroke, or any hospitalization or death from cardiovascular causes. The variables included in the analysis included: vascular risk factors, carotid intima-media thickness (IMT), atherosclerotic burden and basal EPC and CEC count. Multivariate survival analysis was performed using Cox regression analysis. During follow-up, 19 patients (12.66%) had a new vascular event (5 strokes; 3 TIAs; 4 AMI; 6 hospitalizations; 1 death). Vascular events were associated with age (P = 0.039), carotid IMT≥0.9 (P = 0.044), and EPC count (P = 0.041) in the univariate analysis. Multivariate Cox regression analysis showed an independent association with EPC in the lowest quartile (HR: 10.33, 95%CI (1.22-87.34), P = 0.032] and IMT≥0.9 [HR: 4.12, 95%CI (1.21-13.95), P = 0.023]. Basal EPC and IMT≥0.9 can predict future vascular events in patients with AMI and AS, but CEC count does not affect cardiovascular risk
Gathering of aging and estrogen withdrawal in vascular dysfunction of senescent accelerated mice
Les controverses sociotechniques au prisme du Parlement
Le Parlement constitue un espace privilégié pour analyser le déploiement des controverses sociotechniques : non parce qu’il aurait la faculté de les résoudre, notamment via l’OPECST, mais parce qu’il offre de multiples occasions et modalités d’expression et de traitement de ces controverses en son sein. Espace hétérogène et poreux, il participe d’une nouvelle gouvernance des risques, plus soucieuse de leur stabilisation que de leur réduction définitive.The French Parliament offers an ideal place to analyze the unfolding of sociotechnical controversies. Not that it has any capacity to actually resolve these, including its office of science and technology; but rather because it offers a plurality of opportunities for controversies to play out within its two chambers. As a heterogeneous and porous institution, it takes part in a newly formed risk governance that aims to manage rather than definitely solve risk issues
One-year outcome following biological or mechanical valve replacement for infective endocarditis
Background: Nearly half of patients require cardiac surgery during the acute phase of infective endocarditis (IE). We describe the characteristics of patients according to the type of valve replacement (mechanical or biological), and examine whether the type of prosthesis was associated with in-hospital and 1-year mortality. Methods and results: Among 5591 patients included in the International Collaboration on Endocarditis Prospective Cohort Study, 1467 patients with definite IE were operated on during the active phase and had a biological (37%) or mechanical (63%) valve replacement. Patients who received bioprostheses were older (62 vs 54 years), more often had a history of cancer (9% vs 6%), and had moderate or severe renal disease (9% vs 4%); proportion of health care-associated IE was higher (26% vs 17%); intracardiac abscesses were more frequent (30% vs 23%). In-hospital and 1-year death rates were higher in the bioprosthesis group, 20.5% vs 14.0% (p = 0.0009) and 25.3% vs 16.6% (p < .0001), respectively. In multivariable analysis, mechanical prostheses were less commonly implanted in older patients (odds ratio: 0.64 for every 10 years), and in patients with a history of cancer (0.72), but were more commonly implanted in mitral position (1.60). Bioprosthesis was independently associated with 1-year mortality (hazard ratio: 1.298). Conclusions: Patients with IE who receive a biological valve replacement have significant differences in clinical characteristics compared to patients who receive a mechanical prosthesis. Biological valve replacement is independently associated with a higher in-hospital and 1-year mortality, a result which is possibly related to patient characteristics rather than valve dysfunction
Chagas Cardiomiopathy: The Potential of Diastolic Dysfunction and Brain Natriuretic Peptide in the Early Identification of Cardiac Damage
Chagas disease remains a major cause of morbidity and mortality in several
countries of Latin America and has become a potential public health problem in
countries where the disease is not endemic as a result of migration flows.
Cardiac involvement represents the main cause of mortality, but its diagnosis is
still based on nonspecific criteria with poor sensitivity. Early identification
of patients with cardiac damage is desirable, since early treatment may improve
prognosis. Diastolic dysfunction and elevated brain natriuretic peptide levels
are present in different cardiomyopathies and in advanced phases of Chagas
disease. However, there are scarce data about the role of these parameters in
earlier forms of the disease. We conducted a study to assess the diastolic
function, regional systolic abnormalities and brain natriuretic peptide levels
in the different forms of Chagas disease. The main finding of our investigation
is that diastolic dysfunction occurs before any cardiac dilatation or motion
abnormality. In addition, BNP levels identify patients with diastolic
dysfunction and Chagas disease with high specificity. The results reported in
this study could help to early diagnose myocardial involvement and better
stratify patients with Chagas disease
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