A prospective, randomized, controlled, multicentre trial for secondary prevention in patients with chronic coronary syndrome using a smartphone application for digital therapy: the CHANGE study protocol.

Aims: Coronary artery disease (CAD) remains the leading cause of death worldwide. 'Stable' CAD is a chronic progressive condition, which recent European guidelines recommend referring to as 'chronic coronary syndrome' (CCS). Despite therapeutic advances, morbidity and mortality among patients with CCS remain high. Optimal secondary prevention in patients with CCS includes optimization of modifiable risk factors with behavioural changes and pharmacological therapy. The CHANGE study aims to provide evidence for optimization of secondary prevention in CCS patients by using a smartphone application (app). Methods and results: The CHANGE study is designed as a prospective, randomized, controlled trial with a 1:1 allocation ratio, which is currently performed in nine centres in Germany in a parallel group design. 210 patients with CCS will be randomly allocated either to the control group (standard-of-care) or to the intervention group, who will be provided the VantisTherapy* app in addition to standard-of-care to incorporate secondary prevention into their daily life. The study will be performed in an open design. Outcomes will be assessed using objective data from three in-person visits (0, 12, and 24 weeks). Primary outcomes will involve adherence to secondary prevention recommendations and quality of life (QoL). The recruitment process started in July 2022. Conclusion: The CHANGE study will investigate whether a smartphone-guided secondary prevention app, combined with a monitor function compared with standard-of-care, has beneficial effects on overall adherence to secondary prevention guidelines and QoL in patients with CCS. Trial registration: The study is listed at the German study registry (DRKS) under the registered number DRKS00028081.

Vitamin K Epoxide Reductase Complex Subunit 1-Like 1 (VKORC1L1) Inhibition Induces a Proliferative and Pro-inflammatory Vascular Smooth Muscle Cell Phenotype.

Background: Vitamin K antagonists (VKA) are known to promote adverse cardiovascular remodeling. Contrarily, vitamin K supplementation has been discussed to decelerate cardiovascular disease. The recently described VKOR-isoenzyme Vitamin K epoxide reductase complex subunit 1-like 1 (VKORC1L1) is involved in vitamin K maintenance and exerts antioxidant properties. In this study, we sought to investigate the role of VKORC1L1 in neointima formation and on vascular smooth muscle cell (VSMC) function. Methods and Results: Treatment of wild-type mice with Warfarin, a well-known VKA, increased maladaptive neointima formation after carotid artery injury. This was accompanied by reduced vascular mRNA expression of VKORC1L1. In vitro, Warfarin was found to reduce VKORC1L1 mRNA expression in VSMC. VKORC1L1-downregulation by siRNA promoted viability, migration and formation of reactive oxygen species. VKORC1L1 knockdown further increased expression of key markers of vascular inflammation (NFκB, IL-6). Additionally, downregulation of the endoplasmic reticulum (ER) membrane resident VKORC1L1 increased expression of the main ER Stress moderator, glucose-regulated protein 78 kDa (GRP78). Moreover, treatment with the ER Stress inducer tunicamycin promoted VKORC1L1, but not VKORC1 expression. Finally, we sought to investigate, if treatment with vitamin K can exert protective properties on VSMC. Thus, we examined effects of menaquinone-7 (MK7) on VSMC phenotype switch. MK7 treatment dose-dependently alleviated PDGF-induced proliferation and migration. In addition, we detected a reduction in expression of inflammatory and ER Stress markers. Conclusion: VKA treatment promotes neointima formation after carotid wire injury. In addition, VKA treatment reduces aortal VKORC1L1 mRNA expression. VKORC1L1 inhibition contributes to an adverse VSMC phenotype, while MK7 restores VSMC function. Thus, MK7 supplementation might be a feasible therapeutic option to modulate vitamin K- and VKORC1L1-mediated vasculoprotection.

Genetic disruption of multidrug resistance-associated protein 1 improves endothelial function and attenuates atherosclerosis in MRP1-/- LDLr-/- double knockout mice.

INTRODUCTION: Multidrug resistance-associated protein 1 (MRP1) is an anion transporter which is implicated in the efflux of the intracellular antioxidant anion glutathione as well as leukotrienes. Pharmacological inhibition of MRP1 exhibits antioxidative and anti-atherosclerotic effects both in vitro and in vivo. However, pharmacological inhibitors of MRP1 lack selectivity, which prompted us to study the in vivo impact of a genetic disruption of MRP1 on endothelial dysfunction, reactive oxygen species formation and atherogenesis in an atherosclerotic mouse model. MATERIAL AND METHODS: MRP1-/- LDLr-/- double knockout mice. were fed a high-fat and cholesterol-rich diet for 7 weeks. Thereafter, endothelial function was assessed in isolated aortic rings. Reactive oxygen species were quantified by L-012 chemiluminescence, and the atherosclerotic plaque burden was measured following oil red O staining. RESULTS: Endothelium-dependent vasodilation of MRP1-/- LDLr-/- double knockout mice was significantly improved compared to MRP1-competent LDLr-/- single knockout mice (0.56 ±0.06 vs. 0.78 ±0.08; n = 10; p = 0.048). This improvement was accompanied by a significant reduction in reactive oxygen species formation within the aortic tissue (102 ±27 RLU/s/mg vs. 315 ±78 RLU/s/mg, n = 9-11, p = 0.03). Moreover, the atherosclerotic plaque burden of MRP1-/- LDLr-/- double knockout mice was significantly reduced (0.06 ±0.01 vs. 0.12 ±0.02; n = 6; p = 0.047). Finally, arterial blood pressure was significantly reduced in MRP1-/- LDLr-/- double knockout mice (93 ±5 mm Hg vs. 128 ±4 mm Hg; n = 8-12; p < 0.001). CONCLUSIONS: Genetic disruption of MRP1 appears to reduce blood pressure and vascular oxidative stress in vivo, which leads to improved endothelial function and a reduced plaque burden in atherosclerotic mice. Therefore, MRP1 might represent a promising therapeutic target to improve endothelial function in patients suffering from atherosclerosis.

Acute intake of quercetin from onion skin extract does not influence postprandial blood pressure and endothelial function in overweight-to-obese adults with hypertension: a randomized, double-blind, placebo-controlled, crossover trial.

PURPOSE: To determine whether postprandial metabolic and vascular responses induced by a high-fat and high-carbohydrate meal are attenuated by ingestion of the flavonol quercetin. METHODS: Twenty-two overweight-to-obese hypertensive patients participated in a randomized, double-blind, controlled, crossover meal study. They consumed a test meal (challenge) rich in energy (4754 kJ), fat (61.6 g), saturated fatty acids (53 % of total fatty acids), and carbohydrates (113.3 g) with either placebo or 54 mg quercetin. Blood pressure, reactive hyperemia index (RHI), high-sensitive C-reactive protein (hs-CRP), soluble endothelial-derived adhesion molecules, parameters of lipid and glucose metabolism, and markers of antioxidant status were measured before the meal and at 2 and 4 h postprandially. RESULTS: Systolic and diastolic blood pressure increased significantly over time, but were not affected by treatment (placebo or quercetin). During both treatments, serum endothelin-1, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and plasma asymmetric dimethylarginine slightly decreased over time, whereas RHI increased. Serum triglycerides, total cholesterol, and insulin significantly increased, whereas HDL cholesterol and glucose significantly decreased over time, again with no effect of treatment. Plasma α-tocopherol significantly increased, and plasma Trolox equivalent antioxidative capacity decreased over time. Serum hs-CRP, plasma retinol, and ß-carotene did not significantly change during the trial. CONCLUSION: In hypertensive patients, a high-energy meal did not lead to postprandial impairment of vascular endothelial function. Postprandial metabolic responses induced by the challenge, such as lipemia and insulinemia, were not attenuated by the concomitant ingestion of quercetin. CLINICAL TRIAL: This trial was registered at www.germanctr.de/ and http://apps.who.int/trialsearch/ as DRKS00000555.

No effects of quercetin from onion skin extract on serum leptin and adiponectin concentrations in overweight-to-obese patients with (pre-)hypertension: a randomized double-blinded, placebo-controlled crossover trial.

PURPOSE: Chronic low-level systemic and adipose tissue inflammation has been identified as a major etiologic factor in many chronic diseases, including hypertension and cardiovascular diseases. Evidence from experimental studies suggests anti-inflammatory effects of dietary flavonols such as quercetin. METHODS: We investigated the effects of regular intake of quercetin on leptin, adiponectin, biomarkers of inflammation, glucose and insulin in overweight-to-obese patients with pre- and stage 1 hypertension. Another objective was to assess the safety of daily quercetin supplementation measured by parameters of liver and kidney function and of hematology. Subjects (n = 70) were randomized to receive a supra-nutritional dose of 162 mg/d quercetin or placebo in a double-blinded, placebo-controlled crossover trial with 6-week treatment periods separated by a 6-week washout period. Two subjects dropped out for personal reasons. Only data from the remaining 68 subjects were included in the analysis. RESULTS: Compared to placebo, quercetin did not significantly affect serum concentrations of leptin and adiponectin, HOMA-AD or the ratios of leptin/adiponectin and adiponectin/leptin. Neither quercetin nor placebo significantly changed serum C-reactive protein and plasma tumor necrosis factor alpha. Compared to placebo, quercetin did not significantly affect glucose, insulin, HOMA-IR, blood biomarkers of liver and renal function, hematology and serum electrolytes. CONCLUSION: A supra-nutritional dose of 162 mg/d quercetin from onion skin extract for 6 weeks is safe but without significant effects on parameters of systemic and adipose tissue inflammation as well as glucose and insulin in overweight-to-obese subjects with (pre-)hypertension. This trial was registered at www.germanctr.de/ and http://apps.who.int/trialsearch/ as DRKS00000555.

Circulating Microparticles Decrease After Cardiac Stress in Patients With Significant Coronary Artery Stenosis.

BACKGROUND: Cardiac stress leads to a dynamic increase of circulating microparticles (MPs) in healthy individuals that is diminished in individuals with vascular disease. The impact of coronary ischemia on circulating MP level is unknown. This study investigates the kinetics of circulating MPs during cardiac stress in patients with coronary artery stenosis. HYPOTHESIS: Patients with significant coronary stenosis show altered circulating MP levels after cardiac stress. METHODS: Eighty patients with stable coronary artery disease underwent dobutamine stress echocardiography (DSE) on the day before coronary angiography. Before, immediately after, at 4 hours, and at 24 hours after DSE, blood was drawn to determine CD144+ endothelial microparticles (EMPs), CD14+ CD16+ monocyte-derived microparticles (MMPs), and CD31+ CD42b+ platelet microparticles. A significant stenosis was defined as stenosis diameter ≥70% in a major native epicardial coronary artery with a diameter of ≥2.5 mm. RESULTS: Significant coronary artery stenoses were found in 41 patients. In these patients, CD144+ -EMP and CD14+ CD16+ -MMP concentrations decreased immediately after DSE. Stimulation of target endothelial cells with sera from patients with significant coronary artery stenoses significantly augmented endothelial capacity to take up EMPs, but not MMPs, in vitro. Serum-induced enhancement of endothelial phosphatidylserine receptor expression was found as a potential mechanism of increased endothelial EMP uptake and subsequently reduced circulating EMP levels after cardiac stress. CONCLUSIONS: Cardiac ischemia leads to reduced circulating MP levels under cardiac stress. Changes of endothelial MP uptake capacities could be one possible mechanism.

The prognostic value of acute and chronic troponin elevation after transcatheter aortic valve implantation.

AIMS: Myocardial injury occurs frequently following transcatheter aortic valve implantation (TAVI). The aim of this study was to assess timing, predictors, and prognostic value of periprocedural myocardial injury and chronic troponin elevation after TAVI. METHODS AND RESULTS: Two hundred and seventy-six patients (logistic EuroSCORE 26.6±17.1%) underwent transvascular TAVI. Troponin, CK-MB, and NT-proBNP levels were measured before and after TAVI (1 hr, 4 hrs, 24 hrs, 48 hrs, 72 hrs, seven days, three, and six months). Myocardial injury (according to VARC-2 recommendation defined as ΔTroponin ≥15x URL) occurred in 143/276 patients (51.8%) during the first 72 hours following TAVI. Use of a self-expanding prosthesis (p=0.02), coronary artery disease (p=0.04), higher left ventricular ejection fraction (LVEF) (p<0.001), and procedure time (p<0.001) were independent predictors for the development of myocardial injury after TAVI. Thirty-day (4.2% vs. 6.1%; p=0.48) and one-year mortality (19.4% vs. 26.5%; p=0.15) were not related to the incidence of periprocedural myocardial injury. However, patients with chronic troponin elevation after TAVI had an increased one-year mortality risk (HR 4.5, 95% CI: 2.0-10.0; p<0.001). CONCLUSIONS: Myocardial injury defined as ΔTroponin ≥15x URL after TAVI seems to be a procedure-related issue without impact on 30-day and one-year survival. However, monitoring of post-procedural troponin might be useful for prognostication after TAVI.

Impact of peroxisome proliferator-activated receptor γ on angiotensin II type 1 receptor-mediated insulin sensitivity, vascular inflammation and atherogenesis in hypercholesterolemic mice.

INTRODUCTION: The angiotensin II type 1 receptor (AT1R) and the peroxisome proliferator-activated receptor γ (PPARγ) have been implicated in the pathogenesis of atherosclerosis. A number of studies have reported that AT1R inhibition or genetic AT1R disruption and PPARγ activation inhibit vascular inflammation and improve glucose and lipid metabolism, underscoring a molecular interaction of AT1R and PPARγ. We here analyzed the hypothesis that vasculoprotective anti-inflammatory and metabolic effects of AT1R inhibition are mediated by PPARγ. MATERIAL AND METHODS: Female ApoE(-/-)/AT1R(-/-) mice were fedwith a high-fat and cholesterol-rich diet and received continuous treatment with the selective PPARγ antagonist GW9662 or vehicle at a rate of 700 ng/kg/min for 4 weeks using subcutaneously implanted osmotic mini-pumps. Additionally, one group of female ApoE(-/-) mice served as a control group. After treatment for 4 weeks mice were sacrificed and read-outs (plaque development, vascular inflammation and insulinsensitivity) were performed. RESULTS: Using AT1R deficient ApoE(-/-) mice (ApoE(-/-)/AT1R(-/-) mice) we found decreased cholesterol-induced endothelial dysfunction and atherogenesis compared to ApoE(-/-) mice. Inhibition of PPARγ by application of the specific PPARγ antagonist GW9662 significantly abolished the anti-atherogenic effects of AT1R deficiency in ApoE(-/-)/AT1R(-/-) mice (plaque area as % of control: ApoE(-/-): 39 ±5%; ApoE(-/-)/AT1R(-/-): 17 ±7%, p = 0.044 vs. ApoE(-/-); ApoE(-/-)/AT1R(-/-) + GW9662: 31 ±8%, p = 0.047 vs. ApoE(-/-)/AT1R(-/-)). Focusing on IL6 as a pro-inflammatory humoral marker we detected significantly increased IL-6 levels in GW9662-treated animals (IL-6 in pg/ml: ApoE(-/-): 230 ±16; ApoE(-/-)/AT1R(-/-): 117 ±20, p = 0.01 vs. ApoE(-/-); ApoE(-/-)/AT1R(-/-) + GW9662: 199 ±20, p = 0.01 vs. ApoE(-/-)/AT1R(-/-)), while the anti-inflammatory marker IL-10 was significantly reduced after PPARγ inhibition in GW9662 animals (IL-10 in pg/ml: ApoE(-/-): 18 ±4; ApoE(-/-)/AT1R(-/-): 55 ±12, p = 0.03 vs. ApoE(-/-); ApoE(-/-)/AT1R(-/-) + GW9662: 19 ±4, p = 0.03 vs. ApoE(-/-)/AT1R(-/-)). Metabolic parameters of glucose homeostasis (glucose and insulin tolerance test) were significantly deteriorated in ApoE(-/-)/AT1R(-/-) mice treated with GW9662 as compared to vehicle-treated ApoE(-/-)/AT1R(-/-) mice. Systolic blood pressure and plasma cholesterol levels were similar in all groups. CONCLUSIONS: Genetic disruption of the AT1R attenuates atherosclerosis and improves endothelial function in an ApoE(-/-) mouse model of hypercholesterolemia-induced atherosclerosis via PPARγ, indicating a significant role of PPARγ in reduced vascular inflammation, improvement of insulin sensitivity and atheroprotection of AT1R deficiency.

Effects of a quercetin-rich onion skin extract on 24 h ambulatory blood pressure and endothelial function in overweight-to-obese patients with (pre-)hypertension: a randomised double-blinded placebo-controlled cross-over trial.

The polyphenol quercetin may prevent CVD due to its antihypertensive and vasorelaxant properties. We investigated the effects of quercetin after regular intake on blood pressure (BP) in overweight-to-obese patients with pre-hypertension and stage I hypertension. In addition, the potential mechanisms responsible for the hypothesised effect of quercetin on BP were explored. Subjects (n 70) were randomised to receive 162 mg/d quercetin from onion skin extract powder or placebo in a double-blinded, placebo-controlled cross-over trial with 6-week treatment periods separated by a 6-week washout period. Before and after the intervention, ambulatory blood pressure (ABP) and office BP were measured; urine and blood samples were collected; and endothelial function was measured by EndoPAT technology. In the total group, quercetin did not significantly affect 24 h ABP parameters and office BP. In the subgroup of hypertensives, quercetin decreased 24 h systolic BP by -3·6 mmHg (P=0·022) when compared with placebo (mean treatment difference, -3·9 mmHg; P=0·049). In addition, quercetin significantly decreased day-time and night-time systolic BP in hypertensives, but without a significant effect in inter-group comparison. In the total group and also in the subgroup of hypertensives, vasoactive biomarkers including endothelin-1, soluble endothelial-derived adhesion molecules, asymmetric dimethylarginine, angiotensin-converting enzyme activity, endothelial function, parameters of oxidation, inflammation, lipid and glucose metabolism were not affected by quercetin. In conclusion, supplementation with 162 mg/d quercetin from onion skin extract lowers ABP in patients with hypertension, suggesting a cardioprotective effect of quercetin. The mechanisms responsible for the BP-lowering effect remain unclear.

Doppler-based renal resistance index for the detection of acute kidney injury and the non-invasive evaluation of paravalvular aortic regurgitation after transcatheter aortic valve implantation.

AIMS: Acute kidney injury (AKI) is a strong but rather late predictor of mortality after transcatheter aortic valve implantation (TAVI). Early clinically useful markers for the detection of AKI and prediction of outcome are needed in order to control and improve management of periprocedural complications after TAVI. The aim of our study was to assess the predictive value of the Doppler-based renal resistance index (RRI), which correlates inversely with effective renal blood flow and creatinine clearance, for AKI in patients undergoing TAVI and to evaluate its association with paravalvular aortic regurgitation (PAR). METHODS AND RESULTS: TAVI was performed with the Medtronic CoreValve prosthesis in 132 consecutive high-risk patients (mean logistic EuroSCORE: 30.3±18.2%). RRI, serum creatinine and cystatin C level were determined before, and 4 hrs, 24 hrs, 48 hrs, 72 hrs, and 7 days after TAVI. AKI occurred in 32/132 patients (24.2%). While serum creatinine and cystatin C levels decreased at first after TAVI (also in most patients developing AKI), the RRI increased significantly immediately after the procedure from 0.79±0.09 to 0.87±0.12 in patients developing AKI (p=0.003). A RRI >0.85 predicted post-interventional AKI with a sensitivity of 58% and specificity of 86%, and was superior to the serum creatinine level (p<0.001). In addition, an elevated RRI was significantly related to haemodynamic changes after TAVI and was associated with the occurrence of moderate/severe PAR (p<0.001). CONCLUSIONS: Measurement of the Doppler-based RRI predicts risk for AKI and increased mortality rates at an early post-procedural time point and is related to the occurrence of more-than-mild paravalvular aortic regurgitation after TAVI.

Estrogen improves vascular function via peroxisome-proliferator-activated-receptor-γ.

The exact mechanism of estrogen in cardiovascular disease is not fully understood. As estrogen receptors (ERs), the peroxisome-proliferator-activated-receptor-γ (PPARγ) belongs to the family of ligand activated nuclear receptors regulating atheroprotective genes. The aim of this project was to investigate whether vascular effects of estrogen are mediated via PPARγ-regulation in the vascular compartment. Estrogen deficient ovariectomized wildtype-mice (OVX) displayed significant reduction of PPARγ-expression in aortic tissue compared to wildtype-mice with intact ovarian function (Sham). Hormone replacement with subdermal 17ß-estradiol pellets significantly increased vascular PPARγ-expression in ovariectomized female wildtype-mice (OVX/E2). Analogous to wildtype-mice, estrogen-deficient OVX ApoE(-/-)-mice had low vascular PPARγ-expression associated with ROS generation, endothelial dysfunction and atherogenesis. Estrogen replacement (OVX/E2) rescued vascular PPARγ-expression, reduced ROS generation, monocyte recruitment, atherosclerotic lesion formation and improved endothelial function. Inhibition of PPARγ by GW9662, a specific PPARγ-antagonist reduced 17ß-estradiol mediated vascular effects (OVX/E2+GW9662). Finally, despite estrogen deficiency treatment with pioglitazone (OVX+pioglitazone), a selective PPARγ-agonist, compensates deterioration of vascular morphology and function. 17ß-estradiol regulates vascular PPARγ-expression in wildtype- and ApoE(-/-)-mice. The presented data demonstrate the fundamental relevance of PPARγ as downstream target of 17ß-estradiol-related anti-inflammatory and atheroprotective effects within the vascular wall independent of its cardiovascular risk factor modifications.

Aortic regurgitation index defines severity of peri-prosthetic regurgitation and predicts outcome in patients after transcatheter aortic valve implantation.

OBJECTIVES: The aim of this study was to provide a simple, reproducible, and point-of-care assessment of peri-prosthetic aortic regurgitation (periAR) during transcatheter aortic valve implantation (TAVI) and to decipher the impact of this peri-procedural parameter on outcome. BACKGROUND: Because periAR after TAVI might be associated with adverse outcome, precise quantification of periAR is of paramount importance but remains technically challenging. METHODS: The severity of periAR was prospectively evaluated in 146 patients treated with the Medtronic CoreValve (Minneapolis, Minnesota) prosthesis by echocardiography, angiography, and measurement of the aortic regurgitation (AR) index, which is calculated as ratio of the gradient between diastolic blood pressure (DBP) and left ventricular end-diastolic pressure (LVEDP) to systolic blood pressure (SBP): [(DBP - LVEDP)/SBP] × 100. RESULTS: After TAVI, 53 patients (36.3%) showed no signs of periAR and 71 patients (48.6%) showed only mild periAR, whereas 18 patients (12.3%) and 4 patients (2.7%) suffered from moderate and severe periAR, respectively. The AR index decreased stepwise from 31.7 ± 10.4 in patients without periAR, to 28.0 ± 8.5 with mild periAR, 19.6 ± 7.6 with moderate periAR, and 7.6 ± 2.6 with severe periAR (p < 0.001), respectively. Patients with AR index <25 had a significantly increased 1-year mortality risk compared with patients with AR index ≥25 (46.0% vs. 16.7%; p < 0.001). The AR index provided additional prognostic information beyond the echocardiographically assessed severity of periAR and independently predicted 1-year mortality (hazard ratio: 2.9, 95% confidence interval: 1.3 to 6.4; p = 0.009). CONCLUSIONS: The assessment of the AR index allows a precise judgment of periAR, independently predicts 1-year mortality after TAVI, and provides additional prognostic information that is complementary to the echocardiographically assessed severity of periAR.

Systemic inflammatory response syndrome predicts increased mortality in patients after transcatheter aortic valve implantation.

AIMS: The outcome of patients undergoing surgical or interventional therapy is unfavourably influenced by severe systemic inflammation. We assessed the impact of a systemic inflammatory response syndrome (SIRS) on the outcome after transcatheter aortic valve implantation (TAVI). METHODS AND RESULTS: One hundred and fifty-two high-risk patients (mean age: 80.5 ± 6.5 years, mean logistic EuroSCORE: 30.4 ± 8.1%) with symptomatic severe aortic stenosis underwent TAVI. Proinflammatory cytokines [interleukin-6 (IL-6) and interleukin-8 (IL-8)], and acute phase reactants [C-reactive protein (CRP) and procalcitonin (PCT)] were measured at baseline and 1, 4, 24, 48, 72 h, and 7 days after TAVI. Sixty-one of 152 patients developed SIRS during the first 48 h after TAVI. Systemic inflammatory response syndrome patients were characterized by leucocytosis ≥12 × 10(9)/L (83.6 vs. 12.1%; P < 0.001), hyperventilation (80.3 vs. 35.2%; P < 0.001), tachycardia (37.7 vs. 9.9%; P < 0.001), and fever (31.1 vs. 3.3%; P < 0.001) compared with patients without SIRS. Furthermore, the occurrence of SIRS was characterized by a significantly elevated release of IL-6 and IL-8 with subsequent increase in the leucocyte count, CRP, and PCT. Major vascular complications [odds ratio (OR) 5.1, 95% confidence interval (CI): 1.3-19.6; P = 0.018] and the number of ventricular pacing runs (OR 1.7, 95% CI: 1.1-2.8; P = 0.025) were independent predictors of SIRS. The occurrence of SIRS was related to 30-day and 1-year mortality (18.0 vs. 1.1% and 52.5 vs. 9.9%, respectively; P < 0.001) and independently predicted 1-year mortality risk (hazard ratio: 4.3, 95% CI: 1.9-9.9; P < 0.001). CONCLUSIONS: SIRS may occur after TAVI and is a strong predictor of mortality. The development of SIRS could be easily identified by a significant increase in the leucocyte count shortly after TAVI.

Selective inhibition of leukotriene receptor BLT-2 reduces vascular oxidative stress and improves endothelial function in ApoE-/- mice.

Atherosclerosis is a chronic inflammatory disease and represents the main cause of death in the industrialized world. Metabolites of the arachidonic acid derived from the 5-lipoxygenase pathway are known as leukotrienes that mediate various inflammatory processes during atherogenesis. Leukotriene B4 elicits the overexpression of several proinflammatory proteins, promotes chemotaxis and foam cell formation via BLT receptors. Currently, little is known about the implications of the BLT2 receptor in atherogenesis. Here, we tested whether selective inhibition of this receptor influences the progression of atherosclerosis in mice. Apolipoprotein-E deficient mice were fed a high-fat, cholesterol-rich diet to create atherosclerotic conditions (each group n=9). Simultaneously, mice received the pharmacologic BLT2 inhibition (Ly) by intraperitoneal injection every second day 5 mg/kg bw or vehicle. After 8 weeks, mice were killed and experiments were performed. Vascular superoxide release was diminished in mice treated with Ly compared with the control group (68±15 vs 131±20 RLU, P=0.01), as measured by L012 assay. Next, endothelial function was assessed by organ chamber experiments. Endothelial-dependent relaxation was improved in mice treated with the BLT2 receptor antagonist. To determine whether selective inhibition of the BLT2 receptor affects the atherosclerotic plaque growth, immunohistochemical stainings of the aortic root were performed. Oil red O staining revealed no significant differences between both groups (36±3% vs 38±3%). Monocyte infiltration into the vessel wall was analyzed using Moma-2 staining. No significant differences were observed between both groups (31±3% vs 34±2%). Selective inhibition of the BLT2 receptor in mice reduces the release of vascular reactive oxygen species and improves endothelial function in mice. Further experiments are necessary in order to obtain tissue-specific and mechanistical insights.

Redox-sensitive vascular smooth muscle cell proliferation is mediated by GKLF and Id3 in vitro and in vivo.

Reactive oxygen species such as superoxide and hydroxyl radicals have been implicated in the pathogenic growth of various cell types. The molecular mechanisms involved in redox-sensitive cell growth control are poorly understood. Stimulation of cultured vascular smooth muscle cells (VSMC) with xanthin/xanthin oxidase (X/XO) increases proliferation, whereas stimulation with hydrogen peroxide and Fe3+NTA (H-Fe) causes growth arrest of VSMC. Differential Display led to the identification of two novel, differentially regulated redox-sensitive genes. The dominant negative helix-loop-helix protein Id3 is induced by X/XO and down-regulated by H-Fe. The transcription factor gut-enriched Kruppel-like factor (GKLF) is induced by H-Fe but not by X/XO. Induction of GKLF and inhibition of Id3 via transfection experiments leads to growth arrest, whereas overexpression of Id3 and inhibition of GKLF cause cell growth. Id3 down-regulation is induced via binding of GKLF to the Id3 promotor and concomitantly reduced Id3 gene transcription rate. GKLF induction by H-Fe is mediated through hydroxyl radicals, p38MAP kinase-, calcium-, and protein synthesis-dependent pathways. Id3 is induced by X/XO via superoxide, calcium, p38, and p42/44 MAP kinase. GKLF induces and Id3 depresses expression of p21WAF1/Cip1, p27KIP1, p53. Induction of Id3 is accomplished by angiotensin II via superoxide release. A vascular injury mouse model revealed that Id3 is overexpressed in proliferating vascular tissue in vivo. These findings reveal novel mechanisms of redox-controlled cellular proliferation involving GKLF and Id3 that may have general implications for our understanding of vascular and nonvascular growth control.

Destabilization of AT(1) receptor mRNA by calreticulin.

AT(1) receptor activation leads to vasoconstriction, blood pressure increase, free radical release, and cell growth. AT(1) receptor regulation contributes to the adaptation of the renin-angiotensin system to long-term stimulation and serves as explanation for the involvement of the AT(1) receptor in the pathogenesis of cardiovascular disease. The molecular mechanisms involved in AT(1) receptor regulation are poorly understood. Here, we report that angiotensin II accelerates AT(1) receptor mRNA decay in vascular smooth muscle cells. A cognate mRNA region within the 3' untranslated region at bases 2175 to 2195 governs the inducible decay of the AT(1) receptor mRNA. Sequential protein purifications led to the discovery of a novel mRNA binding protein, calreticulin, which mediates destabilization of the AT(1) receptor mRNA. Angiotensin II-caused phosphorylation of calreticulin enables binding of calreticulin to the AT(1) receptor mRNA at bases 2175 to 2195 and propagates calreticulin-induced acceleration of AT(1) receptor mRNA decay. Thus, a novel mRNA binding protein, calreticulin, is discovered, which causes AT(1) receptor mRNA degradation via binding to a distinct mRNA region in the 3' untranslated region. These findings display a novel mechanism of posttranscriptional mRNA processing.

Allelopathic dominance by a tree-associated herb in a California annual grassland.

In some parts of southern California, Pholistoma auritum dominates understory vegetation beneath isolated Quercus agrifolia trees occurring in annual grasslands. Pure stands of P. auritum are maintained in successive years although adjacent to grasses with easily dispersed propagules. Lack of establishment by the grasses in areas covered with previous season's P. auritum litter suggested a germination inhibition mechanism. Laboratory and field tests indicated allelopathic inhibition of grass seedlings by the herb litter. Dominance by an understory species is evaluated in reference to community organization and stability.