Effects of 6-month eicosapentaenoic acid treatment on postprandial hyperglycemia, hyperlipidemia, insulin secretion ability, and concomitant endothelial dysfunction among newly-diagnosed impaired glucose metabolism patients with coronary artery disease. An open label, single blinded, prospective randomized controlled trial.

BACKGROUND: Recent experimental studies have revealed that n-3 fatty acids, such as eicosapentaenoic acid (EPA) regulate postprandial insulin secretion, and correct postprandial glucose and lipid abnormalities. However, the effects of 6-month EPA treatment on postprandial hyperglycemia and hyperlipidemia, insulin secretion, and concomitant endothelial dysfunction remain unknown in patients with impaired glucose metabolism (IGM) and coronary artery disease (CAD). METHODS AND RESULTS: We randomized 107 newly diagnosed IGM patients with CAD to receive either 1800 mg/day of EPA (EPA group, n = 53) or no EPA (n = 54). Cookie meal testing (carbohydrates: 75 g, fat: 28.5 g) and endothelial function testing using fasting-state flow-mediated dilatation (FMD) were performed before and after 6 months of treatment. The primary outcome of this study was changes in postprandial glycemic and triglyceridemic control and secondary outcomes were improvement of insulin secretion and endothelial dysfunction. After 6 months, the EPA group exhibited significant improvements in EPA/arachidonic acid, fasting triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C). The EPA group also exhibited significant decreases in the incremental TG peak, area under the curve (AUC) for postprandial TG, incremental glucose peak, AUC for postprandial glucose, and improvements in glycometabolism categorization. No significant changes were observed for hemoglobin A1c and fasting plasma glucose levels. The EPA group exhibited a significant increase in AUC-immune reactive insulin/AUC-plasma glucose ratio (which indicates postprandial insulin secretory ability) and significant improvements in FMD. Multiple regression analysis revealed that decreases in the TG/HDL-C ratio and incremental TG peak were independent predictors of FMD improvement in the EPA group. CONCLUSIONS: EPA corrected postprandial hypertriglyceridemia, hyperglycemia and insulin secretion ability. This amelioration of several metabolic abnormalities was accompanied by recovery of concomitant endothelial dysfunction in newly diagnosed IGM patients with CAD. Clinical Trial Registration UMIN Registry number: UMIN000011265 ( https://www.upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000013200&language=E ).

Comparison of effects of α-Glucosidase inhibitors and glinide drugs on endothelial dysfunction in diabetic patients with coronary artery disease.

BACKGROUND: Studies have shown that repeated post-prandial hyperglycemia may play an important role in the development of atherosclerosis by suppressing endothelial function. α-Glucosidase inhibitors (α-GIs), which reduce post-prandial hyperglycemia without stimulating insulin secretion, significantly reduce the risk of coronary artery disease (CAD), whereas glinides, which improve post-prandial hyperglycemia through post-prandial insulin secretion, do not appear to affect CAD. METHODS AND RESULTS: A total of 104 diabetic patients with CAD were randomly divided into 2 groups: those treated with miglitol (M-group; n=52) and those treated with nateglinide (N-group; n=52). After 4 months' treatment, although hemoglobin A1c and 1,5-anhydroglucitol were significantly improved in both groups, only the M-group had significant reductions in insulin resistance index and triglyceride/high-density lipoprotein cholesterol (TG/HDL-C; a beneficial index for assessing the presence of small dense low-density lipoprotein, and a marker of atherogenic dyslipidemia). Furthermore, only the M-group had improvement in percentage flow-mediated dilatation (%FMD) and reactive oxygen metabolites. In the M-group, multiple regression analysis showed that improvement in TG/HDL-C, in addition to 1,5-anhydroglucitol, was an independent predictor of improvement in %FMD. CONCLUSIONS: The ameliorating effect of α-GI on post-prandial hyperglycemia without stimulating insulin secretion may improve atherogenic dyslipidemia by reducing insulin resistance. These effects are associated with its beneficial impact on oxidative stress, consequently leading to an improvement in endothelial dysfunction.

Easy-to-use comprehensive speckle-tracking approach for cardiac resynchronization therapy.

BACKGROUND: Left ventricular (LV) dyssynchrony has emerged as an important mechanism contributing to the patient's response to cardiac resynchronization therapy (CRT), but other potential factors, especially LV myocardial viability, are also influential. METHODS AND RESULTS: We studied 132 patients undergoing CRT. LV dyssynchrony was determined by anteroseptal-to-posterior wall delay on the mid-LV short-axis view using 2-dimensional speckle-tracking radial strain (≥130 ms as significant). Global circumferential strain (GCS), considered as a parameter of LV intrinsic myocardial function, was also determined as the peak GCS from the same view. Long-term follow-up was tracked over 40 months. Kaplan-Meier analysis indicated that patients with GCS >3.9% experienced fewer cardiovascular events overall (log-rank P=0.034). Similarly, patients with GCS >3.9% and ≥6.6% experienced fewer cardiovascular events than those with GCS ≤3.9% and <6.6% among patients with and without LV dyssynchrony (log-rank P=0.025 and P=0.029, respectively). An important finding from multivariate Cox proportional hazards analysis was that LV dyssynchrony and GCS were independently associated with cardiovascular events. Of note, only 2±1 min per patient were needed to analyze both LV dyssynchrony and GCS from the same routine mid-LV short-axis view. CONCLUSIONS: This easy-to-use combined assessment of LV dyssynchrony and myocardial function using speckle-tracking strain from the same mid-LV short-axis view may well have clinical implications for CRT.

Qualitative and quantitative assessment of stent restenosis by optical coherence tomography: comparison between drug-eluting and bare-metal stents.

BACKGROUND: We hypothesized that the tissue components of in-stent restenosis (ISR) might differ between drug-eluting stents (DES) and bare-metal stents (BMS) and that these differences could be distinguished by qualitative and quantitative optical coherence tomography (OCT) analyses. METHODS AND RESULTS: One-hundred and twenty-two initial ISR lesions (sirolimus-eluting stents: n=28; paclitaxel-eluting stents: n=51; BMS: n=43) were evaluated with OCT. Based on their OCT appearance, the lesions were classified as homogeneous, layered or heterogeneous. The optical properties of backscatter, attenuation and signal intensity of the neointimal tissue (NIT) were quantified. To evaluate the vascular response after balloon angioplasty (BA), the rate of reduction of the NIT area (NITA) was calculated (NITA before - after BA/NITA before BA at the minimum lumen cross-sectional area). Among the morphologic OCT patterns, the layered type was predominant with DES, whereas lesions were homogeneous with BMS (P<0.001). Backscatter and signal intensity were significantly higher with BMS (P<0.05 and P<0.001 respectively). The NITA reduction rate was significantly greater in the layered and heterogeneous groups than in the homogeneous group (P<0.01). CONCLUSIONS: The morphologic OCT patterns of the NIT in ISR differed significantly between DES and BMS, probably reflecting pathologic differences. Layered and heterogeneous tissues might respond better than homogeneous tissue to simple balloon dilatation, suggesting a possible direction for OCT-based ISR treatment strategies.

Orally administered eicosapentaenoic acid induces rapid regression of atherosclerosis via modulating the phenotype of dendritic cells in LDL receptor-deficient mice.

OBJECTIVE: Eicosapentaenoic acid (EPA) has been shown to have beneficial effects on cardiovascular diseases, although the precise mechanism is unknown. We investigated the effect of EPA on the regression of atherosclerosis. METHODS AND RESULTS: LDL-receptor-deficient mice were fed a high-cholesterol diet for 8 weeks to build up aortic sinus atherosclerotic lesions and then were fed a normal diet with or without 5% EPA for 4 weeks. Atherosclerotic lesions were histologically assessed, and immunologic assays were performed. EPA treatment significantly regressed atherosclerosis (-22.7%, P<0.05) and decreased the content of macrophages, CD4(+) T cells, and dendritic cells (DCs) in atherosclerotic lesions, though only changing the chow never induced the regression. Flow cytometric analysis revealed that EPA increased immature DCs (CD11c(+) CD80(-) CD86(-)), increased the indoleamine 2,3-dioxygenase (IDO) in DCs, and decreased the number of CD4(+) T cells. In the presence of the IDO inhibitor, the beneficial effects of EPA on regression were inhibited, suggesting that the effect of EPA was mainly mediated through IDO. CONCLUSIONS: In addition to lowering plasma cholesterol, EPA regressed atherosclerosis probably due to modulation of DC phenotype and reduction in T cell numbers. The present findings might partly explain the beneficial effects of EPA in clinics and support clinical evidence.

Clinical importance of adherence to treatment with eicosapentaenoic acid by patients with hypercholesterolemia.

BACKGROUND: Despite the risk of critical heart disease, poor adherence to treatment is common in patients with lifestyle-related diseases such as hypercholesterolemia. The association between adherence to treatment and clinical outcome was examined in JELIS (Japan EPA Lipid Intervention Study) and strategies for avoiding poor adherence were explored. METHODS AND RESULTS: Patients taking 80% or more of the study medications were considered to exhibit good adherence. The primary endpoint was either sudden cardiac death or myocardial infarction. Adherence was lower in the eicosapentaenoic acid (EPA) + statin group (66.5%) than in the statin alone group (72.5%). In good adherers with previous coronary artery disease, EPA substantially reduced the risk compared with statin alone (hazard ratio 0.55, 95% confidence intervals 0.34-0.88, P<0.014). Furthermore, the clinical benefit of EPA + statin was significantly larger in patients with good adherence than in those with poor adherence (P=0.041). Finally, a 5-year risk prediction model constructed from the data indicated that complete adherence would lead to 51% reduction of risk compared with non-adherence. CONCLUSIONS: Good adherence to medication was associated with a lower cardiovascular risk than with poor adherence, and the assistance of a pharmacist is of great importance in achieving persistent adherence during treatment.

Preventive effects of eicosapentaenoic acid on coronary artery disease in patients with peripheral artery disease.

BACKGROUND: The JELIS trial examined the preventive effects of eicosapentaenoic acid (EPA) on coronary artery disease (CAD) in hypercholesterolemia. Previous investigators have reported that patients with peripheral artery disease (PAD) have a poor prognosis due to the potential risk for CAD. We conducted a subanalysis to examine whether the incidence of CAD was high in patients with PAD and whether EPA prevented the occurrence of CAD. METHODS AND RESULTS: Of 18,645 the Japan EPA lipid intervention study (JELIS) patients, 223 had PAD (control group; complicated (n=77), newly diagnosed (n=29), EPA group; complicated (n=96), newly diagnosed (n=21)). We analyzed the incidence of major coronary events (MCE) in the 2 groups. Cox proportional hazard ratio adjusted for baseline risk factor levels was used to test differences between the 2 groups. The incidence of MCE in the control group was significantly higher in patients complicated with PAD and in those newly diagnosed with PAD than in patients without PAD (complicated: hazard ratio 1.97, P=0.039; newly diagnosed: hazard ratio 2.88, P=0.030). As for patients with PAD, the EPA group had a significantly lower MCE hazard ratio than the control group (hazard ratio 0.44, 95% confidence interval 0.19-0.97, P=0.041). CONCLUSIONS: Subanalysis of the JELIS trial demonstrated that in patients with PAD the incidence of CAD was higher than in controls, and that EPA markedly reduced the occurrence of CAD in those patients.

Augmentation of vascular remodeling by uncoupled endothelial nitric oxide synthase in a mouse model of diabetes mellitus.

OBJECTIVE: Diabetes mellitus is associated with increased oxidative stress, which induces oxidation of tetrahydrobiopterin (BH4) in vessel wall. Without enough BH4, eNOS is uncoupled to L-arginine and produces superoxide rather than NO. We examined the role of uncoupled eNOS in vascular remodeling in diabetes. METHODS AND RESULTS: Diabetes mellitus was produced by streptozotocin in C57BL/6J mice. Under stable hyperglycemia, the common carotid artery was ligated, and neointimal formation was examined 4 weeks later. In diabetic mice, the neointimal area was dramatically augmented. This augmentation was associated with increased aortic superoxide formation, reduced aortic BH4/dihydrobiopterin (BH2) ratio, and decreased plasma nitrite and nitrate (NOx) levels compared with nondiabetic mice. Chronic BH4 treatment (10 mg/kg/d) reduced the neointimal area in association with suppressed superoxide production and inflammatory changes in vessels. BH4/BH2 ratio in vessel wall was preserved, and plasma NOx levels increased. Furthermore, in the presence of diabetes, overexpression of bovine eNOS resulted in augmentation of neointimal area, accompanied by increased superoxide production in the endothelium. CONCLUSIONS: In diabetes, increased oxidative stress by uncoupled NOSs, particularly eNOS, causes augmentation of vascular remodeling. These findings indicate restoration of eNOS coupling has an atheroprotective benefit in diabetes.

Adenoviral transduction of MRP-1/CD9 and KAI1/CD82 inhibits lymph node metastasis in orthotopic lung cancer model.

Conventional therapies still remain less effective for metastasis of lung cancer, thus leading to a poor prognosis for this disorder. Although the processes involved in metastasis have not yet been clearly elucidated, our previous studies have shown that higher expression levels of MRP-1/CD9 and KAI1/CD82 in cancer cells are significantly correlated with less metastatic potency. To determine whether the gene transfer of these tetraspanins into lung tumor cells may be a useful strategy to regulate metastasis, we adopted an orthotopic lung cancer model produced by the intrapulmonary implantation of Lewis lung carcinoma (LLC) cells and evaluated the metastatic growth in the mediastinal lymph nodes using two different methods of gene delivery as follows: (a) the implantation of LLC cells preinfected with adenovirus encoding either MRP-1/CD9 cDNA, KAI1/CD82 cDNA, or LacZ gene into the mouse lung and (b) the intratracheal administration of these adenoviruses into the mice orthotopically preimplanted with LLC cells. In both cases, we found that the delivery of either MRP-1/CD9 or KAI1/CD82 cDNA dramatically reduced the metastases to the mediastinal lymph nodes in comparison with those of LacZ gene delivery, without affecting the primary tumor growth at the implanted site. These results reemphasize the important role of MRP-1/CD9 and KAI1/CD82 in the suppression of the metastatic process and also show the feasibility of gene therapy when using these tetraspanins for lung cancer to prevent metastasis to the regional lymph nodes. This strategy may therefore be clinically applicable as a prophylactic treatment to suppress the occurrence of lymph node metastasis.

Reduction in the recurrence of stroke by eicosapentaenoic acid for hypercholesterolemic patients: subanalysis of the JELIS trial.

BACKGROUND AND PURPOSE: The JELIS trial examined the preventive effect of eicosapentaenoic acid (EPA) against coronary artery diseases. Hypercholesterolemic patients received statin only (no EPA group: n=9319) or statin with EPA (EPA group: n=9326) for around 5 years. EPA significantly suppressed the incidence of coronary events in previous analysis. Herein, we investigated the effects of EPA on the primary and secondary prevention of stroke. METHODS: We conducted a subanalysis of JELIS with respect to stroke incidence in the primary and secondary prevention subgroups defined as those without and with a prior history of stroke using Cox proportional hazard ratios, adjusted for baseline risk factor levels. RESULTS: As for primary prevention of stroke, this occurred in 114 (1.3%) of 8862 no EPA group and in 133 (1.5%) of 8841 EPA group. No statistically significant difference in total stroke incidence (Hazard Ratio, 1.08; 95% confidence interval, 0.95 to 1.22) was observed between the no EPA and the EPA groups. In the secondary prevention subgroup, stroke occurred in 48 (10.5%) of 457 no EPA group and in 33 (6.8%) of 485 EPA group, showing a 20% relative reduction in recurrent stroke in the EPA group (Hazard Ratio, 0.80; 95% confidence interval, 0.64 to 0.997). CONCLUSIONS: Administration of highly purified EPA appeared to reduce the risk of recurrent stroke in a Japanese population of hypercholesterolemic patients receiving low-dose statin therapy. Further research is needed to determine whether similar benefits are found in other populations with lower levels of fish intake. The trial is registered at ClinicalTrials.gov (number NCT00231738).

Effects of eicosapentaenoic acid on major coronary events in hypercholesterolaemic patients (JELIS): a randomised open-label, blinded endpoint analysis.

BACKGROUND: Epidemiological and clinical evidence suggests that an increased intake of long-chain n-3 fatty acids protects against mortality from coronary artery disease. We aimed to test the hypothesis that long-term use of eicosapentaenoic acid (EPA) is effective for prevention of major coronary events in hypercholesterolaemic patients in Japan who consume a large amount of fish. METHODS: 18 645 patients with a total cholesterol of 6.5 mmol/L or greater were recruited from local physicians throughout Japan between 1996 and 1999. Patients were randomly assigned to receive either 1800 mg of EPA daily with statin (EPA group; n=9326) or statin only (controls; n=9319) with a 5-year follow-up. The primary endpoint was any major coronary event, including sudden cardiac death, fatal and non-fatal myocardial infarction, and other non-fatal events including unstable angina pectoris, angioplasty, stenting, or coronary artery bypass grafting. Analysis was by intention-to-treat. The study was registered at ClinicalTrials.gov, number NCT00231738. FINDINGS: At mean follow-up of 4.6 years, we detected the primary endpoint in 262 (2.8%) patients in the EPA group and 324 (3.5%) in controls-a 19% relative reduction in major coronary events (p=0.011). Post-treatment LDL cholesterol concentrations decreased 25%, from 4.7 mmol/L in both groups. Serum LDL cholesterol was not a significant factor in a reduction of risk for major coronary events. Unstable angina and non-fatal coronary events were also significantly reduced in the EPA group. Sudden cardiac death and coronary death did not differ between groups. In patients with a history of coronary artery disease who were given EPA treatment, major coronary events were reduced by 19% (secondary prevention subgroup: 158 [8.7%] in the EPA group vs 197 [10.7%] in the control group; p=0.048). In patients with no history of coronary artery disease, EPA treatment reduced major coronary events by 18%, but this finding was not significant (104 [1.4%] in the EPA group vs 127 [1.7%] in the control group; p=0.132). INTERPRETATION: EPA is a promising treatment for prevention of major coronary events, and especially non-fatal coronary events, in Japanese hypercholesterolaemic patients.

Relation between plasma adiponectin, high-sensitivity C-reactive protein, and coronary plaque components in patients with acute coronary syndrome.

The present study investigated the relation between plasma high-sensitivity C-reactive protein (hs-CRP) and adiponectin and coronary plaque components in patients with acute coronary syndrome (ACS). Previous studies showed a pivotal role of inflammation in the progression of atherosclerosis and the prognostic value of several biomarkers. However, relations among inflammatory biomarkers and plaque characteristics were unknown. Ninety-three culprit plaques (ACS n = 50, non-ACS n = 43) and 56 nonculprit plaques (ACS n = 28, non-ACS n = 28) were analyzed using Virtual Histology intravascular ultrasound to examine relations among plasma hs-CRP, adiponectin, and ratios of each coronary plaque component. Plasma adiponectin was significantly lower and plasma hs-CRP was significantly higher in patients with than without ACS. Culprit plaques in patients with ACS had greater amounts of necrotic core plaque than those in patients without ACS. There was an inverse relation between serum hs-CRP and adiponectin with regard to necrotic core ratio in both culprit and nonculprit lesions in patients with ACS, but not those without ACS. In conclusion, increased plasma hs-CRP and hypoadiponectinemia might be related to the progression of ACS.

Local overexpression of toll-like receptors at the vessel wall induces atherosclerotic lesion formation: synergism of TLR2 and TLR4.

OBJECTIVE: Atherosclerosis is now considered as a chronic inflammatory disease, and inflammation is closely related to immune systems, which consist of innate-immunity and adaptive-immunity. Recently, toll-like receptors (TLRs) have been identified as key components of innate-immunity. We examined the role of local expressions of TLRs at the vessel wall in atherosclerosis. METHODS AND RESULTS: We transfected cDNA encoding human TLR2 and TLR4 into the carotid arterial vessel wall of rabbits fed high-cholesterol diets with the use of HVJ-liposome. The rabbits were transfected with (1) pCMV-beta-gal, (2) empty vector, (3) TLR2, (4) TLR4, (5) TLR2+4. X-gal staining and immunohistochemical analysis showed that the transfected plasmids were mainly expressed in the media. Neither TLR2 nor TLR4 transfection induced significant augmentation of atherosclerosis. Transfection of TLR2- and TLR4-containing HVJ synergistically accelerated atherosclerosis and increased expressions of vascular cell adhesion molecule 1, intercellular adhesion molecule 1, and MCP-1. Moreover, transfection of TLR2 and TLR4 resulted in synergistic activation of NF-kappaB at the vessel wall in vivo, and in vascular smooth muscle cells in vitro. CONCLUSIONS: Expressions of both TLR2 and TLR4 at the vessel wall synergistically accelerated atherosclerosis. The present study revealed the role of TLRs expressed locally at the vessel wall in the early stage of atherosclerosis.

A specific role for eNOS-derived reactive oxygen species in atherosclerosis progression.

OBJECTIVE: When the availability of tetrahydrobiopterin (BH4) is deficient, endothelial nitric oxide synthase (eNOS) produces superoxide rather than NO (uncoupled eNOS). We have shown that the atherosclerotic lesion size was augmented in apolipoprotein E-deficient (ApoE-KO) mice overexpressing eNOS because of the enhanced superoxide production. In this study, we addressed the specific importance of uncoupled eNOS in atherosclerosis, and the potential mechanistic role for specific versus nonspecific antioxidant strategies in restoring eNOS coupling. METHODS AND RESULTS: We crossed mice overexpressing eNOS in the endothelium (eNOS-Tg) with mice overexpressing GTP-cyclohydrolase I (GCH), the rate-limiting enzyme in BH4 synthesis, to generate ApoE-KO/eNOS-Tg/GCH-Tg mice. As a comparison, ApoE-KO/eNOS-Tg mice were treated with vitamin C. Atherosclerotic lesion formation was increased in ApoE-KO/eNOS-Tg mice compared with ApoE-KO mice. GCH overexpression in ApoE-KO/eNOS-Tg/GCH-Tg mice increased vascular BH4 levels and reduced plaque area. This reduction was associated with decreased superoxide production from uncoupled eNOS. Vitamin C treatment failed to reduce atherosclerotic lesion size in ApoE-KO/eNOS-Tg mice, despite reducing overall vascular superoxide production. CONCLUSION: In contrast to vitamin C treatment, augmenting BH4 levels in the endothelium by GCH overexpression reduced the accelerated atherosclerotic lesion formation in ApoE-KO/eNOS-Tg mice, associated with a reduction of superoxide production from uncoupled eNOS.

Overexpression of endothelial nitric oxide synthase accelerates atherosclerotic lesion formation in apoE-deficient mice.

Nitric oxide (NO) derived from endothelial NO synthase (eNOS) is regarded as a protective factor against atherosclerosis. Therefore, augmentation of eNOS expression or NO production by pharmacological intervention is postulated to inhibit atherosclerosis. We crossed eNOS-overexpressing (eNOS-Tg) mice with atherogenic apoE-deficient (apoE-KO) mice to determine whether eNOS overexpression in the endothelium could inhibit the development of atherosclerosis. After 8 weeks on a high-cholesterol diet, the atherosclerotic lesion areas in the aortic sinus were unexpectedly increased by more than twofold in apoE-KO/eNOS-Tg mice compared with apoE-KO mice. Also, aortic tree lesion areas were approximately 50% larger in apoE-KO/eNOS-Tg mice after 12 weeks on a high-cholesterol diet. Expression of eNOS and NO production in aortas from apoE-KO/eNOS-Tg mice were significantly higher than those in apoE-KO mice. However, eNOS dysfunction, demonstrated by lower NO production relative to eNOS expression and enhanced superoxide production in the endothelium, was observed in apoE-KO/eNOS-Tg mice. Supplementation with tetrahydrobiopterin, an NOS cofactor, reduced the atherosclerotic lesion size in apoE-KO/eNOS-Tg mice to the level comparable to apoE-KO mice, possibly through the improvement of eNOS dysfunction. These data demonstrate that chronic overexpression of eNOS does not inhibit, but accelerates, atherosclerosis under hypercholesterolemia and that eNOS dysfunction appears to play important roles in the progression of atherosclerosis in apoE-KO/eNOS-Tg mice.

Vitamin C restores the contractile response to dobutamine and improves myocardial efficiency in patients with heart failure after anterior myocardial infarction.

BACKGROUND: Excessive oxidative stress is considered one of the mechanisms of a decrease in contractile force without concomitant reduction in oxygen cost in failing myocardium. We hypothesized that the antioxidant vitamin C may help reverse hyporesponsiveness to beta-adrenergic stimulation and improve myocardial efficiency in patients with heart failure (HF) after myocardial infarction (MI). METHODS AND RESULTS: Nineteen patients with mild to moderate HF due to previous MI (mean left ventricular [LV] ejection fraction 39%) were instrumented with conductance and coronary sinus thermodilution catheters. Left ventricular contractility, expressed as E(es), the slope of end-systolic pressure-volume relationship, and mechanical efficiency, expressed as the ratio of LV stroke work (SW) to myocardial oxygen consumption (MVO2), were measured in response to the intravenous infusion of dobutamine (4 microg/kg per min) before (Dob) and during (Dob + Vit C) the infusion of vitamin C (2.0-g bolus injection and subsequent 50-mg/min infusion through the jugular vein) (vitamin C group, n = 10). The infusion of vitamin C augmented the E(es) response to dobutamine by 20% +/- 8% (Dob 2.1 +/- 0.3, Dob + Vit C 2.5 +/- 0.4 mm Hg/mL, P < .01) and the SW/MVO2 response by 21% +/- 5% (Dob 36% +/- 3%, Dob + Vit C 43% +/- 4%, P < .01). In the control group (n = 9), E(es) and SW/MVO2 were measured in response to dobutamine before (Dob) and during (Dob + vehicle) the infusion of saline. No difference in E(es) or SW/MVO2 was observed between Dob and Dob + vehicle (E(es): Dob 2.1 +/- 0.2, Dob + vehicle 2.1 +/- 0.2 mm Hg/mL per square meter, P = nonsignificant) (SW/MVO2: Dob 35% +/- 4%, Dob + vehicle 33% +/- 4%, P = nonsignificant). CONCLUSION: The administration of the antioxidant vitamin C enhances the contractile response to dobutamine and improves myocardial efficiency in patients with HF.

Endothelial lipase is increased by inflammation and promotes LDL uptake in macrophages.

AIM: Endothelial lipase (EL) is a member of the lipoprotein lipase family that regulates HDL metabolism. EL is known to act as a bridging molecule for monocytes or lipoproteins in vascular endothelial cells. We investigated the role and regulatory mechanisms of EL expression in macrophages. METHODS: Macrophages originating from wild-type (EL+/+) and EL-deficient (EL-/-) mice were stimulated with lipopolysaccharide (LPS). The expression of EL mRNA was evaluated by northern blotting. DiI-LDL was used to measure the uptake of native low-density lipoprotein (nLDL). RESULTS: LPS increased EL mRNA levels by increasing intracellular oxidative stress in the macrophages. LPS did not affect EL expression in macrophages derived from Toll-like receptor 4 (TLR4) gene mutant mice, C3H/HeJ. The uptake of nLDL after LPS-treatment was significantly lower in macrophages from EL-/- mice than those from EL+/+ mice. Simvastatin suppressed the LPS-induced upregulation of EL expression and uptake of nLDL. CONCLUSIONS: EL expression is upregulated by LPS via TLR4 and promotes the uptake of nLDL by macrophages. Simvastatin inhibits the LPS-induced up-regulation and uptake in macrophages. Thus, our findings provide a novel role for EL in lipoprotein metabolism and would expand the range of anti-atherogenic effects of statins.

Stoichiometric relationships between endothelial tetrahydrobiopterin, endothelial NO synthase (eNOS) activity, and eNOS coupling in vivo: insights from transgenic mice with endothelial-targeted GTP cyclohydrolase 1 and eNOS overexpression.

Endothelial dysfunction in vascular disease states is associated with reduced NO bioactivity and increased superoxide (O2*-) production. Some data suggest that an important mechanism underlying endothelial dysfunction is endothelial NO synthase (eNOS) uncoupling, whereby eNOS generates O2*- rather than NO, possibly because of a mismatch between eNOS protein and its cofactor tetrahydrobiopterin (BH4). However, the mechanistic relationship between BH4 availability and eNOS coupling in vivo remains undefined because no studies have investigated the regulation of eNOS by BH4 in the absence of vascular disease states that cause pathological oxidative stress through multiple mechanisms. We investigated the stoichiometry of BH4-eNOS interactions in vivo by crossing endothelial-targeted eNOS transgenic (eNOS-Tg) mice with mice overexpressing endothelial GTP cyclohydrolase 1 (GCH-Tg), the rate-limiting enzyme in BH4 synthesis. eNOS protein was increased 8-fold in eNOS-Tg and eNOS/GCH-Tg mice compared with wild type. The ratio of eNOS dimer:monomer was significantly reduced in aortas from eNOS-Tg mice compared with wild-type mice but restored to normal in eNOS/GCH-Tg mice. NO synthesis was elevated by 2-fold in GCH-Tg and eNOS-Tg mice but by 4-fold in eNOS/GCH-Tg mice compared with wild type. Aortic BH4 levels were elevated in GCH-Tg and maintained in eNOS/GCH-Tg mice but depleted in eNOS-Tg mice compared with wild type. Aortic and cardiac O2*- production was significantly increased in eNOS-Tg mice compared with wild type but was normalized after NOS inhibition with Nomega-nitro-L-arginine methyl ester hydrochloride (L-NAME), suggesting O2*- production by uncoupled eNOS. In contrast, in eNOS/GCH-Tg mice, O2*- production was similar to wild type, and L-NAME had no effect, indicating preserved eNOS coupling. These data indicate that eNOS coupling is directly related to eNOS-BH4 stoichiometry even in the absence of a vascular disease state. Endothelial BH4 availability is a pivotal regulator of eNOS activity and enzymatic coupling in vivo.

Neutrophil elastase inhibitor (sivelestat) attenuates subsequent ventilator-induced lung injury in mice.

Mechanical ventilation can paradoxically cause acute lung injury, which is termed ventilator-induced lung injury. Neutrophil recruitment and neutrophil elastase release play a central role in the pathogenesis of ventilator-induced lung injury including cell damage, extracellular matrix degradation and alveolar-capillary hyperpermeability. We therefore speculated that neutrophil elastase inhibition ameliorates ventilator-induced lung injury. Anesthetized C57/BL6 mice received mechanical ventilation with a high tidal volume (V(T); 20 ml/kg) for 4 h. The neutrophil elastase inhibitor (sivelestat, 100 mg/kg) or saline was given intraperitoneally (i.p.) 30 min before ventilation. Sivelestat completely inhibited both neutrophil elastase and myeloperoxidase activities that were increased by ventilation, and attenuated the histopathological degree of lung damage, neutrophil accumulation and lung water content, as well as the concentration of macrophage inflammatory protein (MIP)-2, interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha in bronchoalveolar lavage fluid and serum. Moreover, mechanical ventilation increased the phosphorylation of c-Jun NH2-terminal kinase (JNK) and the expression of early growth response gene-1 (Egr-1) mRNA, and these increases were also recovered by sivelestat. The terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) staining revealed apoptotic cells mainly in alveolar epithelial cells and their numbers corresponded to histological damage. These data suggested that sivelestat could protect against ventilator-induced lung injury by suppressing apoptotic responses through mechanical stress-induced cell signaling in addition to inhibiting neutrophil chemotaxis.

A large abdominal wall mass as an initial manifestation of malignant mesothelioma.

Malignant mesothelioma is relatively rare and usually presents with pleural thickening and effusion at onset. In this report, we describe a 67-year-old male patient whose initial manifestation of mesothelioma was a large mass in the left flank. Mesothelioma was diagnosed from needle biopsy specimens, and, after radiotherapy, the tumor did not recur in this area. However, pleural effusion developed, which was controlled by pleurodesis, and tumors appeared around the descending aorta. Despite further radiotherapy, the patient died of cardiac tamponade due to tumor invasion 38 months after the initial diagnosis. To the best of our knowledge, this is the first description of malignant mesothelioma presenting via initial invasion of the abdominal wall without changes in the thoracic space.