Search

Background: Actual clinical management of ischemic stroke (IS) is based on restoring cerebral blood flow using tissue plasminogen activator (tPA) and/or endovascular treatment (EVT). Mechanical thrombectomy has permitted the analysis of thrombus structural and cellular classic components. Nevertheless, histological assessment of hemostatic parameters such as thrombin-activatable fibrinolysis inhibitor (TAFI) and matrix metalloproteinase 10 (MMP-10) remains unknown, although their presence could determine thrombus stability and its response to thrombolytic treatment, improving patient's outcome. Methods: We collected thrombi ( n = 45) from large vessel occlusion (LVO) stroke patients ( n = 53) and performed a histological analysis of different hemostatic parameters [TAFI, MMP-10, von Willebrand factor (VWF), and fibrin] and cellular components (erythrocytes, leukocytes, macrophages, lymphocytes, and platelets). Additionally, we evaluated the association of these parameters with plasma levels of MMP-10, TAFI and VWF activity and recorded clinical variables. Results: In this study, we report for the first time the presence of MMP-10 and TAFI in all thrombi collected from LVO patients. Both proteins were localized in regions of inflammatory cells, surrounded by erythrocyte and platelet-rich areas, and their content was significantly associated ( r = 0.41, p < 0.01). Thrombus TAFI was lower in patients who died during the first 3 months after stroke onset [odds ratio (OR) (95%CI); 0.59 (0.36-0.98), p = 0.043]. Likewise, we observed that thrombus MMP-10 was inversely correlated with the amount of VWF ( r = -0.30, p < 0.05). Besides, VWF was associated with the presence of leukocytes ( r = 0.37, p < 0.05), platelets ( r = 0.32, p < 0.05), and 3 months mortality [OR (95%CI); 4.5 (1.2-17.1), p = 0.029]. Finally, plasma levels of TAFI correlated with circulating and thrombus platelets, while plasma MMP-10 was associated with cardiovascular risk factors and functional dependence at 3 months. Conclusions: The present study suggests that the composition and distribution of thrombus hemostatic components might have clinical impact by influencing the response to pharmacological and mechanical therapies as well as guiding the development of new therapeutic strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Marta-Enguita, Navarro-Oviedo, Muñoz, Olier-Arenas, Zalba, Lecumberri, Mendioroz, Paramo, Roncal and Orbe.)

Objective: Aortic valve (AV) calcification plays an important role in the progression of aortic stenosis (AS). MMP-10 (matrix metalloproteinase-10 or stromelysin-2) is involved in vascular calcification in atherosclerosis. We hypothesize that MMP-10 may play a pathophysiological role in calcific AS. Approach and Results: Blood samples (n=112 AS and n=349 controls) and AVs (n=88) from patients undergoing valve replacement were analyzed. Circulating MMP-10 was higher in patients with AS compared with controls ( P <0.001) and correlated with TNFα (tumor necrosis factor α; r S =0.451; P <0.0001). MMP-10 was detected by immunochemistry in AVs from patients with AS colocalized with aortic valve interstitial cells markers α-SMA (α-smooth muscle actin) and vimentin and with calcification markers Runx2 (Runt-related transcription factor 2) and SRY (sex-determining region Y)-box 9. MMP-10 expression in AVs was further confirmed by RT-qPCR and western blot. Ex vivo, MMP-10 was elevated in the conditioned media of AVs from patients with AS and associated with interleukin-1β (r S =0.5045, P <0.001) and BMP (bone morphogenetic protein)-2 (r S =0.5003, P <0.01). In vitro, recombinant human MMP-10 induced the overexpression of inflammatory, fibrotic, and osteogenic markers (interleukin-1β, α-SMA, vimentin, collagen, BMP-4, Sox9, OPN [osteopontin], BMP-9, and Smad 1/5/8; P <0.05) and cell mineralization in aortic valve interstitial cells isolated from human AVs, in a mechanism involving Akt (protein kinase B) phosphorylation. These effects were prevented by TIMP-1 (tissue inhibitor of metalloproteinases type 1), a physiological MMP inhibitor, or specifically by an anti-MMP-10 antibody., Conclusions: MMP-10, which is overexpressed in aortic valve from patients with AS, seems to play a central role in calcification in AS through Akt phosphorylation. MMP-10 could be a new therapeutic target for delaying the progression of aortic valve calcification in AS.

Background and Aims: Matrix metalloproteinases (MMPs) have been implicated in atherosclerosis and vascular calcification. Among them, we reported that MMP10 is present in human atheroma, associated with atherosclerosis. However, it remains unclear whether MMP10 is involved in atherogenesis and vascular calcification., Methods: MMP10 was measured in serum from patients with subclinical atherosclerosis and analyzed in carotid endarterectomies by immunostaining. ApoE-deficient mice (Apoe -/- ) were crossed to MMP10-deficient (Mmp10 -/- ) mice and followed up to 20 months. Plaque area and composition were assessed by histology and immunohistochemistry. Inflammatory markers were measured in atherosclerotic plaques by RT-qPCR, and leukocyte subpopulations were analyzed by flow cytometry. In vitro calcification assays were performed in aortic vascular smooth muscle cells (VSMC)., Results: MMP10 serum levels were associated with coronary calcification in subjects with subclinical atherosclerosis. Immunostaining revealed MMP10 expression in human atheromas, spatially associated with calcification areas, and complicated plaques released higher amounts of MMP10 than non-diseased segments. Interestingly, vascular MMP10 expression was confined to the atherosclerotic lesion in Apoe -/- mice, and Apoe -/- Mmp10 -/- showed a substantial reduction in atherosclerotic lesion size, macrophage content and plaque calcification. Reduced local and systemic inflammatory markers could be demonstrated in Apoe -/- Mmp10 -/- by gene expression and flow cytometry analysis. Calcium phosphate deposition and vascular calcification markers were downregulated in VSMC from Apoe -/- Mmp10 -/- mice., Conclusions: Delayed plaque progression and altered cellular composition in the absence of MMP10 suggests that MMP10 plays a role in atherosclerosis, favoring inflammation, development and complication of the plaque., (Copyright © 2018 Elsevier B.V. All rights reserved.)

NADPH oxidase (Nox) variants Nox1, Nox2 and Nox4 are implicated in the progression of liver fibrosis. However, the role of Nox5 is not yet known, mainly due to the lack of this enzyme in rat and mouse genomes. Here we describe the expression and functional relevance of Nox5 in the human cell line of hepatic stellate cells (HSC) LX-2. Under basal conditions, three long (Nox5-L: Nox5α, -β, and -δ) and a short (Nox5-S or Nox5ε) splice variants were detected, which were silenced with specific siRNAs for Nox5. The most abundant isoform was Nox5-S, accounting for more than 90% of Nox5 protein. Overexpression of Nox5β generated reactive oxygen species (ROS) in the presence of calcium, as judged by the production of hydrogen peroxide, L-012 luminescence and cytochrome c reduction. Nox5ε did not generated ROS under these conditions, and a reduced ROS production was observed when co-expressed with Nox5β. In contrast, dihydroethidium oxidation was increased by Nox5β or Nox5ε, suggesting that Nox5ε induced intracellular oxidative stress by an unknown mechanism. Functional studies showed that both Nox5β and Nox5ε stimulated the proliferation of LX-2 cells and the collagen type I levels, while Nox5 siRNAs inhibited these effects. Interestingly, TGF-β and angiotensin II upregulated Nox5 expression, which was reduced in cells pre-incubated with catalase. Further studies silencing Nox5 in TGF-β-treated cells resulted in a reduction of collagen levels via p38 MAPK. Collectively, these results show for the first time that Nox5 can play a relevant role in the proliferation and fibrosis on human HSC., (Copyright © 2018 Elsevier Inc. All rights reserved.)

mPGES-1 (microsomal prostaglandin E synthase-1), the downstream enzyme responsible for PGE 2 (prostaglandin E 2 ) synthesis in inflammatory conditions and oxidative stress are increased in vessels from hypertensive animals. We evaluated the role of mPGES-1-derived PGE 2 in the vascular dysfunction and remodeling in hypertension and the possible contribution of oxidative stress. We used human peripheral blood mononuclear cells from asymptomatic patients, arteries from untreated and Ang II (angiotensin II)-infused mPGES-1 -/- and mPGES-1 +/+ mice, and vascular smooth muscle cells exposed to PGE 2 In human cells, we found a positive correlation between mPGES-1 mRNA and carotid intima-media thickness ( r =0.637; P <0.001) and with NADPH oxidase-dependent superoxide production ( r =0.417; P <0.001). In Ang II-infused mice, mPGES-1 deletion prevented all of the following: (1) the augmented wall:lumen ratio, vascular stiffness, and altered elastin structure; (2) the increased gene expression of profibrotic and proinflammatory markers; (3) the increased vasoconstrictor responses and endothelial dysfunction; (4) the increased NADPH oxidase activity and the diminished mitochondrial membrane potential; and (5) the increased reactive oxygen species generation and reduced NO bioavailability. In vascular smooth muscle cells or aortic segments, PGE 2 increased NADPH oxidase expression and activity and reduced mitochondrial membrane potential, effects that were abolished by antagonists of the PGE 2 receptors (EP), EP1 and EP3, and by JNK (c-Jun N-terminal kinase) and ERK1/2 (extracellular-signal-regulated kinases 1/2) inhibition. Deletion of mPGES-1 augmented vascular production of PGI 2 suggesting rediversion of the accumulated PGH 2 substrate. In conclusion, mPGES-1-derived PGE 2 is involved in vascular remodeling, stiffness, and endothelial dysfunction in hypertension likely through an increase of oxidative stress produced by NADPH oxidase and mitochondria., (© 2018 American Heart Association, Inc.)

Background & Aims: A healthy lifestyle has been associated with longer telomeres, but whether Mediterranean Diet (MeDiet) affect telomere length (TL) has not been fully elucidated yet. Our aim was to assess the relationship between MeDiet and TL in high cardiovascular risk subjects in the context of a randomized nutritional intervention trial., Methods: We assessed 520 participants (55-80 years, 55% women) from the PREDIMED-NAVARRA trial. Leukocyte TL was measured by qPCR at baseline and after 5 years of a dietary intervention program where subjects were randomly assigned to a low-fat control diet or to two MeDiets, one supplemented with extra virgin olive oil (MeDiet-EVOO) and the other with mixed nuts (MeDiet-nuts). A validated 14-item questionnaire was used to appraise baseline adherence of participants to the MeDiet., Results: Better adherence to MeDiet (as appraised by the 14-item score) was associated with longer basal telomeres in women in the baseline cross-sectional analysis, whereas the opposite was observed in men (P interaction = 0.036). Female subjects who scored 10 points had longer basal telomeres (0.27, 95% CI: 0.03-0.52) than women scoring ≤6 points at the beginning of the study (-0.46, 95% CI: -0.85 to -0.7) (P = 0.003). However, allocation to the MeDiet-nuts group (-0.24, 95% CI: -0.38 to -0.01) was associated with a higher risk of telomere shortening after 5 years of intervention, whereas no differences were found for the MeDiet-EVOO group (0.14, 95% CI: 0.02-0.27), in comparison with the Control group (0.07, 95% CI: -0.08 to 0.23) (P = 0.003 and P = 0.537, respectively)., Conclusion: A greater baseline adherence to a Mediterranean dietary pattern was associated with longer telomeres only in women. No beneficial effect of the intervention with the MeDiet for the prevention of telomere shortening in comparison with a low-fat diet was observed., (Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Aim: The interaction between TNF-like weak inducer of apoptosis (TWEAK, Tnfsf12) and the receptor, fibroblast growth factor-inducible 14 (Fn14), regulates vascular damage through different mechanisms, including inflammation. Oxidative stress plays a major role in inflammation and the development of atherosclerosis, but the relationship between TWEAK and oxidative stress is, however, poorly understood., Methods and Results: In this study, we found that TWEAK and Fn14 are co-localized with the NADPH subunits, p22phox and Nox2, in human advanced atherosclerotic plaques. Using primary human macrophages and a murine macrophage cell line, we demonstrate that TWEAK promotes ROS production and enhances NADPH oxidase activity. Hence, we show a direct involvement of the TWEAK-Fn14 axis in oxidative stress, as genetic silencing of Fn14 or Nox2 abrogates the TWEAK-induced ROS production. Furthermore, our results point at Rac1 as an upstream mediator of TWEAK during oxidative stress. Finally, using an in vivo murine model we confirmed the major role of TWEAK in oxidative stress, as genetic silencing of Tnfsf12 in an ApoE(-/-) background reduces the number of DHE and 8-hydroxydeoxyguanosine-positive macrophages by 50%., Conclusions: Our results suggest that TWEAK regulates vascular damage by stimulating ROS production in an Nox2-dependent manner. These new insights into the TWEAK/Fn14 axis underline their potential use as therapeutic targets in atherosclerosis., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.)

Background: Dietary factors can affect telomere length (TL), a biomarker of aging, through oxidation and inflammation-related mechanisms. A Dietary Inflammatory Index (DII) could help to understand the effect of the inflammatory potential of the diet on telomere shortening., Objective: This study aimed to determine the association of the DII with TL and to examine whether diet-associated inflammation could modify the telomere attrition rate after a 5-y follow-up of a Mediterranean dietary intervention., Design: This was a prospective study of 520 participants at high cardiovascular disease risk (mean ± SD age: 67.0 ± 6.0 y, 45% males) from the PREDIMED-NAVARRA (PREvención con DIeta MEDiterránea-NAVARRA) trial. Leukocyte TL was measured by quantitative real-time polymerase chain reaction at baseline and after 5 y of follow-up. The DII was calculated from self-reported data by using a validated 137-item food-frequency questionnaire., Results: Longer telomeres at baseline were found in participants who had a more anti-inflammatory diet (lowest DII score) (P-trend = 0.012). Longitudinal analyses further showed that a greater anti-inflammatory potential of the diet (i.e., a decrease in the DII) could significantly slow down the rate of telomere shortening. Moreover, the multivariable-adjusted OR for short telomeres (z score ≤20th percentile) was 1.80 (95% CI: 1.03, 3.17) in a comparison between the highest (proinflammatory) and the lowest (anti-inflammatory) DII tertiles. Similarly, a greater DII (greatest proinflammatory values) after a 5-y follow-up was associated with almost a 2-fold higher risk of accelerated telomere attrition compared with the highest decrease in DII (greatest anti-inflammatory values) during this period (P-trend = 0.025)., Conclusions: This study showed both cross-sectional and longitudinal associations between the inflammatory potential of the diet and telomere shortening in subjects with a high cardiovascular disease risk. Our findings are consistent with, but do not show, a beneficial effect of adherence to an anti-inflammatory diet on aging and health by slowing down telomere shortening. These results suggest that diet might play a key role as a determinant of TL through proinflammatory or anti-inflammatory mechanisms. This trial was registered at controlled-trials.com as ISRCTN35739639., (© 2015 American Society for Nutrition.)

To assess the potential association between TRX-1/PRX-1 and NADPH oxidase (Nox) activity in vivo and in vitro, TRX-1/PRX-1 levels were assessed by ELISA in 84 asymptomatic subjects with known phagocytic NADPH oxidase activity and carotid intima-media thickness (IMT). We found a positive correlation between TRX-1/PRX-1 and NADPH oxidase-dependent superoxide production (r=0.48 and 0.47; p<0.001 for both) and IMT (r=0.31 and 0.36; p<0.01 for both) adjusted by age and sex. Moreover, asymptomatic subjects with plaques have higher PRX-1 and TRX plasma levels (p<0.01 for both). These data were confirmed in a second study in which patients with carotid atherosclerosis showed higher PRX-1 and TRX plasma levels than healthy subjects (p<0.001 for both). In human atherosclerotic plaques, the NADPH oxidase subunit p22phox colocalized with TRX-1/PRX-1 in macrophages (immunohistochemistry). In monocytes and macrophages, phorbol 12-myristate 13-acetate (PMA) induced NADPH activation and TRX-1/PRX-1 release to the extracellular medium, with a concomitant decrease in their intracellular levels, which was reversed by the NADPH inhibitor apocynin (Western blot). In loss-of-function experiments, genetic silencing of the NADPH oxidase subunit Nox2 blocked PMA-induced intracellular TRX-1/PRX-1 downregulation in macrophages. Furthermore, the PMA-induced release of TRX-1/PRX-1 involves the modulation of their redox status and exosome-like vesicles. TRX-1/PRX-1 levels are associated with NADPH oxidase-activity in vivo and in vitro. These data could suggest a coordinated antioxidant response to oxidative stress in atherothrombosis., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background & Aims: Oxidative stress and inflammation seem to be potential underlying mechanisms for telomere attrition. A lack of specific antioxidants is believed to increase free radical damage and a greater risk for telomere shortening. Our aim was to evaluate the relationship between diet and leukocyte telomere length in a cross-sectional study of children and adolescents. We hypothesized that dietary total antioxidant capacity would be positively associated with telomere length., Methods: Telomere length was measured by quantitative real-time polymerase chain reaction in 287 participants (55% males, 6-18 years), who were randomly selected from the GENOI study., Results: A positive correlation between dietary total antioxidant capacity and telomere length (r = 0.157, p = 0.007) was found after adjustment for age and energy intake. However, higher white bread consumption was associated with shorter telomeres (β = -0.204, p = 0.002) in fully-adjusted models. Interestingly, those individuals who had simultaneously higher dietary total antioxidant capacity and lower white bread consumption significantly presented the longest telomeres. Moreover, the multivariable-adjusted odds ratio for very short telomeres was 0.30 for dietary total antioxidant capacity (p = 0.023) and 1.37 for white bread (p = 0.025)., Conclusion: It was concluded that longer telomeres were associated with higher dietary total antioxidant capacity and lower white bread consumption in Spanish children and adolescents. These findings might open a new line of investigation about the potential role of an antioxidant diet in maintaining telomere length., (Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Context: Telomeres are biomarkers of biological aging. Shorter telomeres have been associated with increased adiposity in adults. However, this relationship remains unclear in children and adolescents., Objective: To evaluate the association between telomere length (TL) and adiposity markers in overweight/obese adolescents after an intensive program. We hypothesize that greater TL at baseline would predict a better response to a weight loss treatment., Design Setting Patients and Intervention: The EVASYON is a multidisciplinary treatment program for adolescents with overweight and obesity that is aimed at applying the intervention to all possibly involved areas of the individual, such as dietary habits, physical activity and cognitive and psychological profiles. Seventy-four participants (36 males, 38 females, 12-16 yr) were enrolled in the intervention program: 2 months of an energy-restricted diet and a follow-up period (6 months)., Main Outcome: TL was measured by quantitative real-time polymerase chain reaction at baseline and after 2 months; meanwhile, anthropometric variables were also assessed after 6 months of follow-up., Results: TL lengthened in participants during the intensive period (+1.9±1.0, p<0.001) being greater in overweight/obese adolescents with the shortest telomeres at baseline (r = -0.962, p<0.001). Multivariable linear regression analysis showed that higher baseline TL significantly predicted a higher decrease in body weight (B = -1.53, p = 0.005; B = -2.25, p = 0.047) and in standard deviation score for body mass index (BMI-SDS) (B = -0.22, p = 0.010; B = -0.47, p = 0.005) after the intensive and extensive period treatment respectively, in boys., Conclusion: Our study shows that a weight loss intervention is accompanied by a significant increase in TL in overweight/obese adolescents. Moreover, we suggest that initial longer TL could be a potential predictor for a better weight loss response.

Herein, we investigate whether the NADPH oxidase might be playing a key role in the degree of oxidative stress in the senescence-accelerated mouse prone-8 (SAM-P8). To this end, the activity and expression of the NADPH oxidase, the ratio of glutathione and glutathione disulfides (GSH/GSSG), and the levels of malonyl dialdehyde (MDA) and nitrotyrosine (NT) were determined in renal tissue from SAM-P8 mice at the age of 1 and 6 months. The senescence-accelerated-resistant mouse (SAM-R1) was used as control. At the age of 1 month, NADPH oxidase activity and Nox2 protein expression were higher in SAM-P8 than in SAM-R1 mice. However, we found no differences in the GSH/GSSG ratio, MDA, NT, and Nox4 levels between both groups of animals. At the age of 6 months, SAM-R1 mice in comparison to SAM-P8 mice showed an increase in NADPH oxidase activity, which is associated with higher levels of NT and increased Nox4 and Nox2 expression levels. Furthermore, we found oxidative stress hallmarks including depletion in GSH/GSSG ratio and increase in MDA levels in the kidney of SAM-P8 mice. Finally, NADPH oxidase activity positively correlated with Nox2 expression in all the animals (r = 0.382, P < 0.05). Taken together, our data allow us to suggest that an increase in NADPH oxidase activity might be an early hallmark to predict future oxidative stress in renal tissue during the aging process that takes place in SAM-P8 mice.

Aims: The NADPH oxidases constitute a major source of superoxide anion (·O2(-)) in hypertension. Several studies suggest an important role of NADPH oxidases in different effects mediated by transforming growth factor-β₁ (TGF-β₁). We investigated whether a chronic treatment with P144, a peptide synthesized from type III TGF-β₁ receptor, inhibited NADPH oxidases in the renal cortex of spontaneously hypertensive rats (SHR)., Results: Here, we show that chronic administration of P144 significantly reduced the NADPH oxidase expression and activity as well as the oxidative stress observed in control vehicle-treated SHR (V-SHR). In addition, P144 was also able to reduce the significant increase in the renal fibrosis and in mRNA expression of different components of collagen metabolism, as well as in the levels of connective tissue growth factor observed in V-SHR. Finally, TGF-β₁-stimulated NRK52E exhibited a significant increase in NADPH oxidase expression and activity as well as a TGF-β₁-dependent intracellular pathway that were inhibited in the presence of P144., Innovation: Our experimental evidence suggests that reversing oxidative stress may be therapeutically useful in preventing fibrosis-associated renal damage. We show here that (i) the TGF-β₁-NADPH oxidases axis is crucial in the development of fibrosis in an experimental hypertensive renal disease animal model, and (ii) the use of P144 reverses TGF-β₁-dependent NADPH oxidase activity; thus, P144 may be considered a novel therapeutic tool in kidney disease associated with hypertension., Conclusion: We demonstrate that P144 inhibits NADPH oxidases and prevents oxidative stress in kidneys from hypertensive rats. Our data also suggest that these effects are associated with the renal antifibrotic effect of P144.

Oxidative stress is implicated in diabetes. The NADPH oxidases are the main source of superoxide in phagocytic and vascular cells, and p22phox is a key subunit. Genetic variants of CYBA, the human p22phox gene, associate with cardiovascular disease. We investigated the association of the A640G polymorphism with diabetes and its impact on phagocytic NADPH oxidase-dependent superoxide production and subclinical atherosclerosis. We studied 1212 subjects in which clinical parameters including carotid intima-media thickness (cIMT) were assessed. The A640G polymorphism was genotyped by TaqMan probes. In 496 subjects, the NADPH oxidase-dependent superoxide production in peripheral blood mononuclear cells was assessed by chemiluminescence. The GG genotype prevalence was significantly higher in type 2 diabetic patients than in non-diabetic subjects. Peripheral blood mononuclear cells from diabetic GG patients presented higher NADPH oxidase-dependent superoxide production than those of diabetic AA/AG patients. Within the diabetic group, GG patients presented higher cIMT levels than AA/AG patients. The A640G CYBA polymorphism may be a marker of oxidative stress risk and may be indicative of subclinical atherosclerosis in type 2 diabetes.

Introduction and Objectives: Advanced kidney disease is a major health problem due to its association with high cardiovascular morbidity and mortality. Early recognition of advanced kidney disease is the mainstay to avoid its progression. Since metabolic syndrome and insulin resistance are risk factors for both cardiovascular and advanced kidney disease, we investigated the relationship of early kidney disease (EKD) with metabolic syndrome and insulin resistance, and their association with surrogate markers of arteriosclerosis., Methods: We studied 1498 subjects. Insulin resistance was defined as HOMA ≥3.7 mmol (μU)/L(2) and EKD as stages 1 and 2 of the NKF-KDOQI. Carotid intima-media thickness was used as a surrogate marker of arteriosclerosis., Results: The presence of one trait of metabolic syndrome was associated with an odds ratio (OR) for EKD of 2.3 (95% confidence interval [CI], 1.18-4.48) that increased to 6.72 (95% CI, 3.56-13.69) in subjects with the syndrome. All the traits of the syndrome except low level of high-density lipoproteins showed an increased OR for EKD. Increasing HOMA was also directly correlated with higher OR for EKD, being as high as 3.89 (95% CI, 1.99-7.59) for subjects in the fourth quartile. Subjects with the syndrome plus EKD showed an increased intima-media thickness compared with those without kidney disease., Conclusions: Insulin resistance and all metabolic syndrome traits except low level of high-density lipoproteins were significantly associated with an increased OR for EKD. Both metabolic syndrome and EKD were independently and additively related to the presence of surrogate markers of arteriosclerosis., (Copyright © 2010 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.)

Oxidative stress plays a key role in the pathophysiology of coronary artery disease, and constitutes a common mechanism behind the risk factors associated with this disease such as atherosclerosis, hypertension, diabetes and the metabolic syndrome. Oxidative stress is defined as an imbalance between the production of reactive oxygen and nitrogen species and the detoxification by the appropriate cellular systems. Reactive oxygen species induce cardiovascular dysfunction by modulating cell contraction/dilation, migration, growth/apoptosis and extracellular matrix protein turnover, which contribute to vascular and cardiac remodeling. In the last decade, the NADPH oxidase family has emerged as one of the most relevant sources of reactive oxygen species within the cardiovascular system. Recent data suggest a significant role of the genetic background in NADPH oxidase regulation. Common genetic polymorphisms within the promoter and exonic sequences of CYBA, the gene that encodes the p22phox subunit of the NADPH oxidase, have been characterized in the context of cardiovascular diseases. This review aims to present the current state of research into these polymorphisms with regards to their relationship to coronary artery disease., (Copyright (c) 2010 Prous Science, S.A.U. or its licensors. All rights reserved.)

Insulin stimulates superoxide (O(2)(-)) production in monocytes and macrophages. However, the mechanisms through which insulin induces O(2)(-) production are not completely understood. In this study, we (a) characterized the enzyme and the pathways involved in insulin-stimulated O(2)(-) production in human monocytes and murine macrophages, and (b) analyzed the consequences of insulin-stimulated O(2)(-) production on the cellular phenotype in these cells. We showed that insulin stimulated O(2)(-) production, and promoted p47(phox) translocation to the plasma membrane. Insulin-induced O(2)(-) production and p47(phox) translocation were prevented in the presence of specific inhibitors of PI3K and PKC. Insulin-mediated NADPH oxidase activation stimulated MMP-9 activation in monocytes and cell proliferation in macrophages. The effect of insulin on these phenotypic responses was mediated through NFkappaB, p38MAPK, and ERK 1/2 activation. Small-interfering RNA-specific gene silencing targeted specifically against Nox2 reduced the cognate protein expression, decreased insulin-induced O(2)(-) production, inhibited the turn on of NFkappaB, p38MAPK, and ERK 1/2, and reduced cell proliferation in macrophages. These findings suggest a pivotal role for NADPH oxidase in insulin-induced proliferation and proteolytic activation in monocytes and macrophages, respectively, and identify a pathway that may play a pathological role in hyperinsulinemic states.

Oxidative stress induced by superoxide is implicated in hypertension. NADPH oxidase is the main source of superoxide in phagocytic and vascular cells, and the p22phox subunit is involved in NADPH oxidase activation. Recently we reported an association of -930A/G polymorphism in the human p22phox gene promoter with hypertension. This study was designed to investigate the functional role of this polymorphism in hypertension. We thus investigated the relationships between the -930A/G polymorphism and p22phox expression and NADPH oxidase-mediated superoxide production in phagocytic cells from 70 patients with essential hypertension and 70 normotensive controls. Genotyping of the polymorphism was performed by restriction fragment length polymorphism. NADPH oxidase activity was determined by chemiluminescence assays, and p22phox mRNA and protein expression was measured by Northern and Western blotting, respectively. Compared with hypertensive subjects with the AA/AG genotype, hypertensive subjects with the GG genotype exhibited increased (P<0.05) phagocytic p22phox mRNA (1.26+/-0.06 arbitrary unit [AU] versus 0.99+/-0.03 AU) and protein levels (0.58+/-0.05 AU versus 0.34+/-0.04 AU) and enhanced NADPH oxidase activity (1998+/-181 counts/s versus 1322+/-112 counts/s). No differences in these parameters were observed among genotypes in normotensive cells. Transfection experiments on vascular smooth muscle cells showed that the A-to-G substitution of this polymorphism produced an increased reporter gene expression in hypertensive cells. Nitric oxide production, as assessed by measurement of serum nitric oxide metabolites, was lower in GG hypertensive subjects than in AA/AG hypertensive subjects. In conclusion, these results suggest that hypertensive subjects carrying the GG genotype of the p22phox -930A/G polymorphism are highly exposed to NADPH oxidase-mediated oxidative stress.

Objectives: We have investigated whether the A1166C polymorphism of the angiotensin II type 1 (AT1) receptor gene modulates the effects of angiotensin II on collagen type I turnover and myocardial stiffness in hypertension., Methods: We studied 255 hypertensive patients before and after 1 year of treatment with either losartan (n = 185) or atenolol (n = 70). Serum concentrations of the carboxy-terminal propeptide of procollagen type I (PIP) and the carboxy-terminal telopeptide of collagen type I (CITP), markers of extracellular collagen type I synthesis and degradation, respectively, were measured by specific radioimmunoassays. Left ventricular chamber stiffness (KLV), was determined from the deceleration time of the early mitral filling wave, as measured by Doppler echocardiography. Hypertensives were genotyped by polymerase chain reaction and divided in two subgroups: AA (n = 126) and AC/CC (n = 129)., Results: Baseline PIP and KLV were increased (P < 0.01) in AA hypertensives compared with AC/CC hypertensives. No changes in baseline CITP were observed between the two subgroups of hypertensives. Confounding factors were similar between the two subgroups of hypertensives. Administration of losartan was associated with reduction (P < 0.01) in PIP and KLV in AA hypertensives but not in AC/CC hypertensives. Treatment with atenolol did not change PIP and KLV in either subgroup of hypertensives. No changes in CITP were observed with the two treatments., Conclusion: These findings suggest that the A1166C polymorphism of the AT1 receptor gene is associated with collagen type I synthesis and myocardial stiffness in patients with hypertensive heart disease.