Differences in the feasibility, anatomical parameters predicting procedural difficulty, and isolation area of a left atrial posterior wall isolation using radiofrequency versus cryoballoon catheters.

BACKGROUNDS: The difficulty and outcome of the adjunctive left atrial posterior wall isolation (LAPWI) in patients with persistent atrial fibrillation (PersAF) may be affected by the ablation energy used. This study aimed to compare the completion rate, anatomical parameters predicting procedural difficulty, and the isolation area of a LAPWI between the use of radiofrequency (RFA) and cryoballoon ablation (CBA). METHODS: We enrolled 95 and 93 patients with PersAF who underwent pulmonary vein isolation (PVI)+LAPWI using RFA (RF group) and CBA (CB group), respectively. Preoperative computed tomography was used to evaluate the anatomical features associated with an incomplete LAPWI. Post-ablation 3-dimensional maps were analyzed to quantify the isolation area. RESULTS: The completion rate of the LAPWI was significantly higher in the RF group than the CB group without touch-up RFA (88.4% vs. 72.0%; p = .005). Predictors of incomplete LAPWI were a longer left inferior pulmonary vein (LIPV)-esophageal distance (p < .001) for RFA and a steeper angle of the LAPW (p < .001) and longer transverse LAPW diameter (p = .016) for CBA. The isolated non-PV area with RFA or CBA alone was significantly greater in the CB group than the RF group (27.5 ± 9.5 cm2 vs. 22.9 ± 6.9 cm2 ; p < .001). CONCLUSION: The position of the esophagus at a distance from the LIPV was associated with an incomplete LAPWI using RFA, while a steeper angle of the LAPW and transverse enlargement of the LAPW were associated with that using CBA. The completion rate of the LAPWI was higher with RFA, but the isolation area outside of the PVs was greater with CBA.

Prevention of Contrast-Induced Nephropathy After Emergency Percutaneous Coronary Intervention With a Single Bolus Administration of High-Concentrate Sodium Bicarbonate　- Rationale and Design of a Single-Arm Study Compared With Historical Controls.

Background: Contrast-induced nephropathy (CIN) is clinically important because of its poor prognosis. The incidence of CIN is higher in emergency than elective percutaneous coronary intervention (PCI) because there is no established method to prevent CIN. The aim of this study is to evaluate whether bolus administration of a concentrated solution of sodium bicarbonate can prevent CIN in patients undergoing emergency PCI. Methods and Results: This multicenter prospective single-arm trial with historical controls will include patients who are aged ≥20 years and will undergo cardiac catheterization for suspected acute myocardial infarction (AMI). Patients will receive an intravenous bolus administration of concentrated sodium bicarbonate solution (7% or 8.4%, 20 mEq) and will be observed for 72±12 h. Data for the control group, comprising all patients who underwent PCI for AMI between January 1, 2020 and December 31, 2020 across participating hospitals, will be extracted. The primary endpoint is the incidence of CIN, defined as an increase in serum creatinine of >0.5 mg/dL or >25% from baseline within 48±12 h. We will evaluate the endpoints in the prospective group and compare them with those in the historical control group. Conclusions: This study will evaluate whether a single bolus administration of concentrated sodium bicarbonate can prevent CIN after emergency PCI.

Adenosine-sensitive atrial tachycardia originating from the para-Hisian region with a slow conduction zone in the anteroseptal left atrium.

Adenosine-sensitive atrial tachycardias (ATs) originating from the para-Hisian region have been reported, and the responsible mechanism is considered to be reentry. As an alternative strategy to ablation at the earliest activation site (EAS) close to the atrioventricular node, previous reports safely eliminated these ATs at the entrance of the slow conduction zone, indicated by a manifest entrainment-guided strategy, but no report has successfully ablated those ATs using the same strategy in the left atrium. We describe a case of adenosine-sensitive AT originating from the para-Hisian region that could be eliminated at a remote site from the EAS indicated by the demonstration of manifest entrainment from the high anteroseptal left atrium. .

Microbicidal effects of weakly acidified chlorous acid water against feline calicivirus and Clostridium difficile spores under protein-rich conditions.

Sanitation of environmental surfaces with chlorine based-disinfectants is a principal measure to control outbreaks of norovirus or Clostridium difficile. The microbicidal activity of chlorine-based disinfectants depends on the free available chlorine (FAC), but their oxidative potential is rapidly eliminated by organic matter. In this study, the microbicidal activities of weakly acidified chlorous acid water (WACAW) and sodium hypochlorite solution (NaClO) against feline calcivirus (FCV) and C. difficile spores were compared in protein-rich conditions. WACAW inactivated FCV and C. difficile spores better than NaClO under all experimental conditions used in this study. WACAW above 100 ppm FAC decreased FCV >4 log10 within 30 sec in the presence of 0.5% each of bovine serum albumin (BSA), polypeptone or meat extract. Even in the presence of 5% BSA, WACAW at 600 ppm FAC reduced FCV >4 log10 within 30 sec. Polypeptone inhibited the virucidal activity of WACAW against FCV more so than BSA or meat extract. WACAW at 200 ppm FAC decreased C. difficile spores >3 log10 within 1 min in the presence of 0.5% polypeptone. The microbicidal activity of NaClO was extensively diminished in the presence of organic matter. WACAW recovered its FAC to the initial level after partial neutralization by sodium thiosulfate, while no restoration of the FAC was observed in NaClO. These results indicate that WACAW is relatively stable under organic matter-rich conditions and therefore may be useful for treating environmental surfaces contaminated by human excretions.

Prognostic Value of Urinary Neutrophil Gelatinase-Associated Lipocalin on the First Day of Admission for Adverse Events in Patients With Acute Decompensated Heart Failure.

BACKGROUND: Urinary neutrophil gelatinase-associated lipocalin (U-NGAL) is an early predictor of acute kidney injury and adverse events in various diseases; however, in acute decompensated heart failure patients, its significance remains poorly understood. This study aimed to investigate the prognostic value of U-NGAL on the first day of admission for the occurrence of acute kidney injury and long-term outcomes in acute decompensated heart failure patients. METHODS AND RESULTS: We studied 260 acute decompensated heart failure patients admitted to our department between 2011 and 2014 by measuring U-NGAL in 24-hour urine samples collected on the first day of admission. Primary end points were all-cause death, cardiovascular death, and heart failure admission. Patients were divided into 2 groups according to their median U-NGAL levels (32.5 µg/gCr). The high-U-NGAL group had a significantly higher occurrence of acute kidney injury during hospitalization than the low-U-NGAL group (P=0.0012). Kaplan-Meier analysis revealed that the high-U-NGAL group exhibited a worse prognosis than the low-U-NGAL group in all-cause death (hazard ratio 2.07; 95%CI 1.38-3.12, P=0.0004), cardiovascular death (hazard ratio 2.29; 95%CI 1.28-4.24, P=0.0052), and heart failure admission (hazard ratio 1.77; 95%CI 1.13-2.77, P=0.0119). The addition of U-NGAL to the estimated glomerular filtration rate significantly improved the predictive accuracy of all-cause mortality (P=0.0083). CONCLUSIONS: In acute decompensated heart failure patients, an elevated U-NGAL level on the first day of admission was related to the development of clinical acute kidney injury and independently associated with poor prognosis.

Suppressed Production of Soluble Fms-Like Tyrosine Kinase-1 Contributes to Myocardial Remodeling and Heart Failure.

Soluble fms-like tyrosine kinase-1 (sFlt-1), an endogenous inhibitor of vascular endothelial growth factor and placental growth factor, is involved in the pathogenesis of cardiovascular disease. However, the significance of sFlt-1 in heart failure has not been fully elucidated. We found that sFlt-1 is decreased in renal failure and serves as a key molecule in atherosclerosis. In this study, we aimed to investigate the role of the decreased sFlt-1 production in heart failure, using sFlt-1 knockout mice. sFlt-1 knockout mice and wild-type mice were subjected to transverse aortic constriction and evaluated after 7 days. The sFlt-1 knockout mice had significantly higher mortality (52% versus 15%; P=0.0002) attributable to heart failure and showed greater cardiac hypertrophy (heart weight to body weight ratio, 8.95±0.45 mg/g in sFlt-1 knockout mice versus 6.60±0.32 mg/g in wild-type mice; P<0.0001) and cardiac dysfunction, which was accompanied by a significant increase in macrophage infiltration and cardiac fibrosis, than wild-type mice after transverse aortic constriction. An anti-placental growth factor-neutralizing antibody prevented pressure overload-induced cardiac hypertrophy, fibrosis, and cardiac dysfunction. Moreover, monocyte chemoattractant protein-1 expression was significantly increased in the hypertrophied hearts of sFlt-1 knockout mice compared with wild-type mice. Monocyte chemoattractant protein-1 inhibition with neutralizing antibody ameliorated maladaptive cardiac remodeling in sFlt-1 knockout mice after transverse aortic constriction. In conclusion, decreased sFlt-1 production plays a key role in the aggravation of cardiac hypertrophy and heart failure through upregulation of monocyte chemoattractant protein-1 expression in pressure-overloaded heart.

Prognostic Impact of Placental Growth Factor on Mortality and Cardiovascular Events in Dialysis Patients.

BACKGROUND: Placental growth factor (PlGF), a member of the vascular endothelial growth factor (VEGF) family, has recently emerged as a predictor of survival and cardiovascular risk. Along with others, we have shown an independent association between PlGF and cardiovascular events in CKD patients, but not much is known about patients receiving dialysis. METHODS: We studied 205 dialysis patients undergoing cardiac catheterization at the Nara Medical University between April 1, 2004, and December 31, 2012. Serum levels of PlGF and VEGF were measured with ELISA in all the patients. RESULTS: During a median follow-up of 20 months, 121 participants died from any cause or experienced a cardiovascular event. In the fully adjusted analysis, having an above-median PlGF or VEGF level was associated with a hazards ratio for adverse outcomes of 2.55 (1.72-3.83) and 1.39 (0.95-2.04), respectively. Using a multimarker strategy in a model with age, serum albumin, history of coronary artery disease, brain natriuretic peptide and PlGF, patients with 2, 3 and 4 positive markers had a 3.82-, 5.77- and 6.59-fold higher risk of mortality or a cardiovascular event, respectively, compared to those with no positive markers. The model with PlGF had a significantly higher c-statistic, integrated discrimination improvement index and category-free net reclassification improvement index than the model without PlGF. CONCLUSION: PlGF is independently associated with mortality and cardiovascular events, but the association between VEGF and adverse events was attenuated with covariate adjustment. The addition of PlGF to models with established clinical predictors provides additional useful prognostic information in patients receiving dialysis.

Placental Growth Factor as a Predictor of Cardiovascular Events in Patients with CKD from the NARA-CKD Study.

Placental growth factor (PlGF) contributes to atherogenesis through vascular inflammation and plaque destabilization. High levels of PlGF may be associated with mortality and cardiovascular disease, but the relationship between PlGF level and adverse outcomes in patients with CKD is unclear. We conducted a prospective cohort study of 1351 consecutive participants with CKD enrolled in the Novel Assessment of Risk management for Atherosclerotic diseases in CKD (NARA-CKD) study between April 1, 2004, and December 31, 2011. During a median follow-up of 3 years, 199 participants died and 383 had cardiovascular events, defined as atherosclerotic disease or heart failure requiring hospitalization. In adjusted analyses, mortality and cardiovascular risk increased in each successive quartile of serum PlGF level; hazard ratios (HRs) (95% confidence intervals [95% CIs]) for mortality and cardiovascular risk, respectively, were 1.59 (0.83 to 3.16) and 1.55 (0.92 to 2.66) for the second quartile, 2.97 (1.67 to 5.59) and 3.39 (2.20 to 5.41) for the third quartile, and 3.87 (2.24 to 7.08) and 8.42 (5.54 to 13.3) for the fourth quartile. The composite end point of mortality and cardiovascular events occurred during the study period in 76.4% of patients in both the highest PlGF quartile (≥19.6 pg/ml) and the lowest eGFR tertile (<30 ml/min per 1.73 m(2)). The association between PlGF and mortality or cardiovascular events was not attenuated when participants were stratified by age, sex, traditional risk factors, and eGFR. These data suggest elevated PlGF is an independent risk factor for all-cause mortality and cardiovascular events in patients with CKD.

Suppressed soluble Fms-like tyrosine kinase-1 production aggravates atherosclerosis in chronic kidney disease.

Patients with chronic kidney disease (CKD) die of cardiovascular diseases for unknown reasons. Blood vessel formation in plaques and its relationship with plaque stability could be involved with signaling through the Flt-1 receptor and its ligands, vascular endothelial growth factor, and the closely related placental growth factor (PlGF). Flt-1 also exists as a circulating regulatory splice variant short-inhibitory form (sFlt-1) that serves as a decoy receptor, thereby inactivating PlGF. Heparin releases sFlt-1 by displacing the sFlt-1 heparin-binding site from heparin sulfate proteoglycans. Heparin could provide diagnostic inference or could also induce an antiangiogenic state. In the present study, postheparin sFlt-1 levels were lower in CKD patients than in control subjects. More importantly, sFlt-1 levels were inversely related to atherosclerosis in CKD patients, and this correlation was more robust after heparin injection, as verified by subsequent cardiovascular events. Knockout of apolipoprotein E (ApoE) and/or sFlt-1 showed that the absence of sFlt-1 worsened atherogenesis in ApoE-deficient mice. Thus, the relationship between atherosclerosis and PlGF signaling, as regulated by sFlt-1, underscores the underappreciated role of heparin in sFlt-1 release. These clinical and experimental data suggest that novel avenues into CKD-dependent atherosclerosis and its detection are warranted.

Effect of low-dose aspirin on primary prevention of cardiovascular events in Japanese diabetic patients at high risk.

BACKGROUND: Benefit of low-dose aspirin for primary prevention of cardiovascular events in diabetes remains controversial. The American Diabetes Association (ADA), the American Heart Association (AHA), and the American College of Cardiology Foundation (ACCF) recommend aspirin for high-risk diabetic patients: older patients with additional cardiovascular risk factors. We evaluated aspirin's benefit in Japanese diabetic patients stratified by cardiovascular risk. METHODS AND RESULTS: In the JPAD trial, we enrolled 2,539 Japanese patients with type 2 diabetes and no history of cardiovascular disease. We randomly assigned them to aspirin (81-100 mg daily) or no aspirin groups. The median follow-up period was 4.4 years. We stratified the patients into high-risk or low-risk groups, according to the US recommendation: age (older; younger) and coexisting cardiovascular risk factors. The risk factors included smoking, hypertension, dyslipidemia, family history of coronary artery disease, and proteinuria. Most of the patients were classified into the high-risk group, consisting of older patients with risk factors (n=1,804). The incidence of cardiovascular events was higher in this group, but aspirin did not reduce cardiovascular events (hazard ratio [HR], 0.83; 95% confidence interval [CI]: 0.58-1.17). In the low-risk group, consisting of older patients without risk factors and younger patients (n=728), aspirin did not reduce cardiovascular events (HR, 0.55; 95% CI: 0.23-1.21). These results were unchanged after adjusting for potential confounding factors. CONCLUSIONS: Low-dose aspirin is not beneficial in Japanese diabetic patients at high risk.

An elevated ratio of placental growth factor to soluble fms-like tyrosine kinase-1 predicts adverse outcomes in patients with stable coronary artery disease.

OBJECTIVE: To investigate the predictive values of placental growth factor (PlGF) and its endogenous antagonist, soluble fms-like tyrosine kinase-1 (sFlt-1), for the long-term prognosis of patients with stable coronary artery disease (CAD). Both PlGF and sFlt-1 play important roles in the pathological mechanisms of atherosclerosis. We recently demonstrated that the plasma levels of these molecules are correlated with the severity of coronary atherosclerosis. METHODS: We enrolled 464 patients with stable CAD who consecutively underwent coronary angiography. Baseline blood samples were collected from the femoral artery immediately before coronary angiography (after the administration of 20 units of heparin), and the plasma levels of PlGF and sFlt-1 were measured. A Cox proportional hazard regression analysis was performed to evaluate the relationship between these parameters and the occurrence of all-cause death (ACD) and total cardiovascular events (TCVE) during a median follow-up of 3.3 years. RESULTS: A total of 31 ACDs and 51 TCVEs occurred. Patients with higher PlGF/sFlt-1 ratios (>4.22×10(-2)) had a significantly higher risk of both ACD and TCVE than patients with lower ratios (<4.22×10(-2)) (hazard ratio [HR]: 3.32, 95% confidence interval [CI]: 1.43 to 7.72, p=0.005, and HR: 2.23, 95% CI: 1.23 to 4.03, p=0.008, respectively). A multivariate analysis showed the PlGF/sFlt-1 ratio to be an independent predictor for ACD, but not TCVE. CONCLUSION: The baseline PlGF/sFlt-1 ratio is an independent predictor of long-term adverse outcomes in patients with stable CAD.

A new drug delivery system for intravenous coronary thrombolysis with thrombus targeting and stealth activity recoverable by ultrasound.

OBJECTIVES: The purpose of this study was to develop a new intelligent drug delivery system for intracoronary thrombolysis with a strong thrombolytic effect without increasing bleeding risk. BACKGROUND: Rapid recanalization of an occluded coronary artery is essential for better outcomes in acute myocardial infarction. Catheter-based recanalization is widely accepted, but it takes time to transport patients. Although the current fibrinolytic therapy can be started quickly, it cannot achieve a high reperfusion rate. Recently, we generated nanoparticles comprising tissue-type plasminogen activator (tPA), basic gelatin, and zinc ions, which suppress tPA activity by 50% with 100% recovery by ultrasound (US) in vitro. METHODS: The thrombus-targeting property of nanoparticles was examined by an in vitro binding assay with von Wilbrand factor and with a mouse arterial thrombosis model in vivo. The thrombolytic efficacy of nanoparticles was evaluated with a swine acute myocardial infarction model. RESULTS: Nanoparticles bound to von Wilbrand factor in vitro and preferentially accumulated at the site of thrombus in a mouse model. In a swine acute myocardial infarction model, plasma tPA activity after intravenous injection of nanoparticles was approximately 25% of tPA alone and was recovered completely by transthoracic US (1.0 MHz, 1.0 W/cm(2)). During US application, plasma tPA activity near the affected coronary artery was recovered and was higher than that near the femoral artery. Although treatment with tPA alone (55,000 IU/kg) recanalized the occluded coronary artery in only 1 of 10 swine, nanoparticles containing the same dose of tPA with US achieved recanalization in 9 of 10 swine within 30 min. CONCLUSIONS: We developed an intelligent drug delivery system with promising potential for better intravenous coronary thrombolysis.

Ultrasound-responsive thrombus treatment with zinc-stabilized gelatin nano-complexes of tissue-type plasminogen activator.

This study is undertaken to design zinc-stabilized gelatin nano-complexes of tissue-type plasminogen activator (t-PA) for thrombolytic therapy where the t-PA activity can be recovered in the blood circulation upon ultrasound irradiation. Various molecular weights of gelatin were complexed with t-PA by their simply mixing in aqueous solution. Then, zinc acetate, calcium acetate or magnesium acetate was added to form nano-sized gelatin-t-PA complexes. The complexes had the apparent molecular size of about 100 nm. When zinc ions were added to the gelatin-t-PA complexes, the t-PA activity was suppressed most strongly to 57% of the original, free t-PA activity. Upon ultrasound exposure in vitro, the t-PA activity was fully recovered. A cell culture experiment with L929 fibroblasts demonstrated no cytotoxicity of complexes at the concentration used for the in vivo experiment. The half-life of t-PA in the blood circulation prolonged by the complexation with gelatin and zinc ions. The zinc-stabilized t-PA-gelatin complex is a promising t-PA delivery system which can manipulate the thrombolytic activity by the local ultrasound irradiation.

Reduction of circulating soluble fms-like tyrosine kinase-1 plays a significant role in renal dysfunction-associated aggravation of atherosclerosis.

BACKGROUND: Renal dysfunction is commonly accompanied by a worsening of atherosclerosis; however, the underlying molecular mechanism is not fully understood. We examined the role played by soluble fms-like tyrosine kinase-1 (sFlt-1), an endogenous antagonist of the proatherogenic cytokine placental growth factor (PlGF), in the worsening of atherosclerosis in patients with renal dysfunction and in an animal model of renal failure. METHODS AND RESULTS: In this study, 329 patients who received cardiac catheterization and 76 patients who underwent renal biopsy were enrolled. Both plasma sFlt-1 levels and renal sFlt-1 mRNA expression were positively correlated with estimated glomerular filtration rate (P<0.01). The PlGF/sFlt-1 ratio was negatively correlated with estimated glomerular filtration rate (P<0.01), whereas plasma PlGF levels were not affected by it. The PlGF/sFlt-1 ratio was significantly higher in patients with multivessel coronary artery disease than in patients with single-vessel or no coronary artery disease. The reduction of circulating sFlt-1 and renal sFlt-1 mRNA levels was confirmed in five-sixths (5/6)-nephrectomized apolipoprotein E-deficient mice that developed experimental renal dysfunction. Atherosclerotic plaque area and macrophage infiltration into the plaque were significantly higher in 5/6-nephrectomized apolipoprotein E-deficient mice than in control mice, but replacement therapy with recombinant sFlt-1 significantly reduced both plaque formation and macrophage infiltration. CONCLUSIONS: The present study demonstrates that a reduction in the circulating levels of sFlt-1 is associated with the worsening of atherosclerosis that accompanies renal dysfunction.

Usefulness of soluble Fms-like tyrosine kinase-1 as a biomarker of acute severe heart failure in patients with acute myocardial infarction.

Placental growth factor and vascular endothelial growth factor increase angiogenesis and promote healing after acute myocardial infarction (MI), but the significance of soluble Fms-like tyrosine kinase-1 (sFlt-1), an antagonist of placental growth factor and vascular endothelial growth factor, in the setting of acute MI has not been elucidated. The development of acute heart failure in the immediate period after MI is a dreaded complication, but there are no useful biomarkers that identify patients at risk of acute heart failure. We wished to investigate the clinical significance of circulating sFlt-1 during acute MI. We enrolled 174 patients with acute MI, and arterial blood sampling was performed. Plasma levels of sFlt-1 were measured by enzyme-linked immunosorbent assay and their relation to clinical parameters was analyzed. Circulating levels of sFlt-1 on admission were significantly increased in patients with acute MI compared to controls (528.1 +/- 290.9 vs 355.7 +/- 205.0 pg/ml, p <0.001). Circulating levels of sFlt-1 on admission were significantly higher in patients who developed severe acute heart failure requiring mechanical circulatory support devices compared to those with stable hemodynamics (611.4 +/- 373.6 vs 494.6 +/- 243.9 pg/ml, p = 0.016). Moreover, circulating levels of sFlt-1 on admission were directly related to duration of hospitalization. Multivariate logistic analysis showed that hemodynamic instability was predicted by sFlt-1 on admission and left ventricular systolic pressure. In conclusion, the circulating level of sFlt-1 is increased in patients with acute MI, and the sFlt-1 level on admission is a promising biomarker for the development of severe acute heart failure after MI.

Treatment with recombinant placental growth factor (PlGF) enhances both angiogenesis and arteriogenesis and improves survival after myocardial infarction.

BACKGROUND: Placental growth factor (PlGF), a homolog of vascular endothelial growth factor, is reported to stimulate angiogenesis and arteriogenesis in pathological conditions. It was recently demonstrated that PlGF is rapidly produced in myocardial tissue during acute myocardial infarction (MI). However, the effects of exogenous PlGF administration on the healing process after MI are not fully understood. The purpose of the present study was to examine whether PlGF treatment has therapeutic potential in MI. METHODS AND RESULTS: Recombinant human PlGF (rhPlGF: 10 microg) was administered continuously for 3 days in a mouse model of acute MI. rhPlGF treatment significantly improved survival rate after MI and preserved cardiac function relative to control mice. The numbers of CD31-positive cells and alpha-smooth muscle actin-positive vessels in the infarct area were significantly increased in the rhPlGF group. Endothelial progenitor cells (Flk-1(+)Sca-1(+) cells) were mobilized by rhPlGF into the peripheral circulation. Furthermore, rhPlGF promoted the recruitment of GFP-labeled bone marrow cells to the infarct area, but only a few of those migrating cells differentiated into endothelial cells. CONCLUSIONS: Exogenous PlGF plays an important role in healing processes by improving cardiac function and stimulating angiogenesis following MI. It can be considered as a new therapeutic molecule.

Regulation of aldosterone and cortisol production by the transcriptional repressor neuron restrictive silencer factor.

Aldosterone synthase (CYP11B2) and 11 beta-hydroxylase (CYP11B1) regulate aldosterone and cortisol production, respectively. The expression of these enzymes is promoted by calcium influx through Cav3.2, a T-type calcium channel. Neuron-restrictive silencer factor (NRSF) binds to neuron-restrictive silencer element (NRSE) to suppress the transcription of NRSE-containing genes. We found a NRSE-like sequence in human CYP11B2 and CYP11B1 genes as well as the CACNA1H gene of many mammalian species. The CACNA1H gene encodes the alpha-subunit of Cav3.2. Here we investigated how NRSF/NRSE regulates aldosterone and cortisol synthesis. Inhibition of endogenous NRSF by an adenovirus-expressing dominant-negative NRSF (AD/dnNRSF) increased human CYP11B2 and CYP11B1 mRNA expression, leading to aldosterone and cortisol secretion in human adrenocortical (H295R) cells. In reporter gene experiments, NRSE suppressed luciferase reporters driven by CYP11B2 and CYP11B1 promoters and dnNRSF enhanced them. Moreover, cotransfection of dnNRSF increased luciferase activity of reporter genes after deletion or mutation of NRSE, suggesting that NRSF/NRSE regulates transcription of CYP11B2 and CYP11B1 genes indirectly. AD/dnNRSF augmented mRNA expression of rat CYP11B2 and CYP11B1 genes, neither of which contains a NRSE-like sequence in rat adrenal cells. AD/dnNRSE also significantly increased CACNA1H mRNA in H295R and rat adrenal cells. Efonidipine, a T/L-type calcium channel blocker, significantly suppressed dnNRSF-mediated up-regulation of CYP11B2 and CYP11B1 expression. Moreover, NRSF/NRSE is also involved in angiotensin II- and K(+)-stimulated augmentation of CYP11B2 and CYP11B1 gene transcription. In conclusion, NRSF/NRSE controls aldosterone and cortisol synthesis by regulating CYP11B2 and CYP11B1 gene transcription mainly through NRSF/NRSE-mediated enhancement of the CACNA1H gene.

Human placental ectonucleoside triphosphate diphosphohydrolase gene transfer via gelatin-coated stents prevents in-stent thrombosis.

BACKGROUND: In-stent thrombosis is mainly triggered by adenosine diphosphate (ADP)-dependent platelet aggregation after percutaneous coronary stent implantation. Ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) rapidly hydrolyzes ADP to adenosine monophosphate, inhibiting platelet aggregation. We tested the hypothesis that local delivery of human placental E-NTPDase (pE-NTPDase) gene into injured arteries via gene-eluting stent could prevent subacute in-stent thrombosis. METHODS AND RESULTS: We generated gene-eluting stents by coating bare metal stents with cationic gelatin hydrogel containing pE-NTPDase cDNA (pE-NTPDase stent), and implanted the stents into rabbit femoral arteries (FA) prone to production of platelet-rich thrombi due to repeated balloon injury at 4-week intervals. After the second injury, E-NTPDase gene expression was severely decreased; however, the implantation of pE-NTPDase stent increased E-NTPDase mRNA levels and NTPDase activity to higher level than normal FA. The FAs with pE-NTPDase stents maintained patency in all rabbits (P<0.01), whereas the stent-implanted FAs without pE-NTPDase gene showed low patency rates (17% to 25%). The occlusive platelet-rich thrombi, excessive neointimal growth, and infiltration of macrophages were inhibited in stent implanted FA with pE-NTPDase gene, but not without pE-NTPDase gene. CONCLUSIONS: Human pE-NTPDase gene transfer via cationic gelatin-coated stents inhibited subacute in-stent thrombosis and suppressed neointimal hyperplasia and inflammation without antiplatelet drugs.

Blocking T-type Ca2+ channels with efonidipine decreased plasma aldosterone concentration in healthy volunteers.

Efonidipine can block both L- and T- type Ca2+ channels. In a previous in vitro study, we clarified that efonidipine dramatically suppresses aldosterone secretion from human adrenocortical tumor cells during angiotensin II (Ang II)- and K+-stimulation, whereas nifedipine, a dominant L-type Ca2+ channel antagonist, does not. This study was conducted to assess the in vivo effects of efonidipine and nilvadipine on the plasma aldosterone concentration. Placebo, 40 mg of efonidipine, or 2 mg of nilvadipine was administered to five healthy male volunteers. Hemodynamic parameters (pulse rate [PR] and blood pressure [BP]), plasma concentrations of neurohormonal factors (plasma renin activity, Ang II, aldosterone, and adrenocorticotropic hormone [ACTH]), and serum concentrations of Na+ and K+ were measured before and 6 h after administration of the agents. All three agents had little effect on PR and BP. Efonidipine and nilvadipine significantly increased plasma renin activity and Ang II. Both had little effect on ACTH, Na+, and K+. The plasma aldosterone concentration was significantly decreased after efonidipine treatment (88.3 +/- 21.3 to 81.6 +/- 24.9 pg/ml, p = 0.0407), whereas it was significantly increased after nilvadipine treatment (66.5 +/- 12.2 to 82.17 +/- 16.6 pg/ml, p = 0.0049). Placebo had little effect on neurohormonal factors. Efonidipine decreased plasma aldosterone concentration despite the increase in plasma renin activity and Ang II, suggesting that T-type Ca2+ channels may also play an essential role in the secretion of aldosterone in healthy human volunteers.

Inflammatory response to acute myocardial infarction augments neointimal hyperplasia after vascular injury in a remote artery.

OBJECTIVE: Percutaneous coronary intervention (PCI) is currently the most widely accepted treatment for acute myocardial infarction (AMI). It remains unclear, however, whether post-AMI conditions might exacerbate neointimal hyperplasia and restenosis following PCI. Given that both a medial smooth muscle cell lineage and a bone marrow (BM)-derived hematopoietic stem cell lineage are now thought to contribute to neointima formation, the primary aims of the present study were to determine whether AMI augments neointimal hyperplasia at sites of arterial injury, and whether BM-derived cells contribute to that process. METHODS AND RESULTS: We simultaneously generated models of AMI and arterial injury in the same mice, some of which had received BM transplantation. We found that AMI augments neointimal hyperplasia at sites of femoral artery injury by approximately 35% (P<0.05), but that while BM-derived cells contributed to neointimal hyperplasia, they did not contribute to the AMI-related augmentation. Expression of interleukin (IL)-6 mRNA was approximately 7-fold higher in the neointimas of mice subjected to both AMI and arterial injury than in those of mice subjected to arterial injury alone. In addition, we observed increased synthesis of tumor necrosis factor (TNF)-alpha within infarcted hearts and TNF-alpha receptor type 1 (TNFR1) within injured arteries. Chronic treatment with pentoxifylline, which mainly inhibits TNF-alpha synthesis, reduced levels of circulating TNF-alpha and attenuated neointimal hyperplasia after AMI. CONCLUSIONS: Conditions after AMI could exacerbate postangioplasty restenosis, not by increasing mobilization of BM-derived cells, but by stimulating signaling via TNF-alpha, TNFR1 and IL-6.