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When human low density lipoprotein (LDL) obtained from 10 volunteers was incubated in air at 37 degrees C in the presence of various concentrations of copper, an increase in fluorescence was observed with emission maximum at 430 nm when excitation was performed at 360 nm. The fluorescence increase was inhibited by ethylenediamine tetraacetic acid and by 4-methyl-2,6-di-tert-butylphenol. The fluorescence was found to be tightly bound to the protein moiety. Furthermore, Cu2+ modification of LDL was associated with a decrease in the reactive amino groups of apolipoprotein B and in the uptake of the lipoprotein by rabbit fibroblasts. Under our conditions, the fluorescence increase showed two consecutive periods; an inhibition period during which the fluorescence increased only weakly, and a propagation period with a rapid increase in fluorescence that was linear for at least 5 h. Both periods were influenced by copper concentration. The study also shows that the extent of fluorescence generated upon LDL oxidation varied greatly in the volunteers. Thus, while the results demonstrate that the fluorescence increase may likely monitor the extent of the apoB derivatization, the calculation of the fluorescence development rate of the propagation period together with the duration of the inhibition period may constitute a quantitative measurement of the susceptibility of apoB to be derivatized.

Bicuspid aortic valve (BAV) is the most common congenital heart malformation. BAV patients are at increased risk for aortic valve disease (stenosis/regurgitation), infective endocarditis, thrombi formation and, in particular, aortic dilatation, aneurysm and dissection. This review aims at exploring the possible interplay among genetics, extracellular matrix remodeling, abnormal signaling pathways, oxidative stress and inflammation in contributing to BAV-associated aortopathy (BAV-A-A). Novel circulating biomarkers have been proposed as diagnostic tools able to improve risk stratification in BAV-A-A. However, to date, the precise molecular and cellular mechanisms that lead to BAV-A-A remain unknown. Genetic, hemodynamic and cardiovascular risk factors have been implicated in the development and progression of BAV-A-A. Oxidative stress may also play a role, similarly to what observed in atherosclerosis and vulnerable plaque formation. The identification of common pathways between these 2 conditions may provide a platform for future therapeutic solutions., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Heart failure (HF) is a clinical syndrome caused by structural and/or functional cardiac abnormalities, resulting in a reduced cardiac output and/or elevated intracardiac pressures at rest or during stress. It is the leading cause of hospitalization in Internal Medicine departments. This article aims at reviewing evidence of the importance of ultrasound in HF both for hospitalized patients and in the follow-up. Ultrasound may be used as a recovery monitoring instrument at the bedside and also as a global cardiovascular assessment tool for these patients. HF represents an exciting opportunity to create an integrative ultrasound approach in Internal Medicine and/or Geriatric departments. The authors plan a five-step ultrasound examination to evaluate and monitor HF patients during hospitalization and follow-up. They call this examination: the "ABCDE" score. It includes the evaluations of A, the ankle-brachial index, B, the B-lines, C, the carotid intima media thickness, D, the diameter of the abdominal aorta and of the inferior cava vein and E, the echocardiographic assessment of the ejection fraction. This score may represent an integrative ultrasound approach in Internal Medicine and/or Geriatric departments., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Asymmetric dimethylarginine (ADMA) has been reported to affect the synthesis of nitric oxide (NO) in endothelial cells by inhibiting endothelial NO synthase (eNOS) activity and to cause endothelial dysfunction in humans. This study was conducted in human umbilical vein endothelial cells (HUVECs) to evaluate the effect of nebivolol, a selective beta1-adrenergic receptor antagonist, on ADMA concentration and on dimethylarginine dimethylaminohydrolase (DDAH2), the enzyme that regulates ADMA catabolism. Nebivolol dose-dependently decreased ADMA/symmetric dimethylarginine (SDMA) ratio (p from <0.01 to <0.001). This was parallelled by a dose-dependent increase in DDAH2 mRNA (p from <0.01 to <0.001) and protein expression (p from <0.01 to <0.001) and activity (p from <0.01 to <0.001). The small interference RNA (siRNA)-mediated knockdown of DDAH2 abolished the modification of DDAH2 expression (p<0.001) and ADMA/SDMA ratio (p<0.001) induced by nebivolol. In conclusion, the results of this study demonstrate that nebivolol reduces ADMA concentration by increasing DDAH2 expression and activity. Our in vitro findings describe a novel vascular effect of nebivolol and clearly identify this compound as the first antihypertensive agent that modulates DDAH2 in endothelial cells.

Nebivolol, a third generation selective beta(1)-adrenoceptor (beta(1)-AR) antagonist, has been reported to reduce intracellular oxidative stress and to induce the release of nitric oxide (NO) from the endothelium. Nebivolol is also subjected to a complex metabolic process where glucuronidation, aromatic and alicyclic hydroxylation are the major pathways leading to several metabolites. We have studied the effect of nebivolol, its enantiomers and metabolites on intracellular oxidative stress and NO availability in human umbilical vein endothelial cells (HUVECs). Furthermore, since the receptors involved in this endothelial effect of nebivolol remain controversial, we have studied this matter by the use of antagonists of beta-AR. dl-Nebivolol, d-nebivolol and l-nebivolol significantly reduced the formation of reactive oxygen species (ROS) and superoxide induced by oxidized-low density lipoprotein (ox-LDL), although the racemic and l-form were significantly more active than d-nebivolol in this activity. A marked decrease in the availability of intracellular NO was found in HUVECs exposed to ox-LDL and this parameter was normalized by the prior incubation with dl-nebivolol, d-nebivolol and l-nebivolol; the effect of racemate was mainly mimicked by its l-enantiomer. eNOS activity significantly increased by a 5-min contact of HUVECs with dl-nebivolol and l-nebivolol, but not with d-nebivolol, and a similar pattern was observed when the intracellular calcium increase was measured. The metabolites A2, A3', A12 and A14 but not A1, A3 and R 81,928, derived from different metabolic pathways, retained the antioxidant activity of the parent racemic compound dl-nebivolol, reducing the intracellular formation of ROS and superoxide. The effects of dl-nebivolol on intracellular formation of NO, eNOS activity and intracellular Ca(2+) were partially antagonized by the antagonists of beta(1-2)-AR nadolol or by the beta(3)-AR antagonist SR59230A and further antagonized by their combination or by (beta(1-2-3)-AR antagonist bupranolol. In conclusion, this study shows that the NO releasing effect of nebivolol is mainly due to its l-enantiomer; the racemate and its enantiomers possess a remarkable antioxidant activity that contributes to its effect on the cellular NO metabolism and the activation of beta(3)-AR through a calcium dependent pathway is involved in the mechanisms leading to the NO release.

Objectives: To measure circulating levels of oxidized-low-density lipoproteins (ox-LDL) in patients with stable and unstable angina and controls, and to investigate their correlation with the extent of coronary artery disease (CAD) and the presence of complex plaques at coronary angiography., Methods and Results: Circulating ox-LDL were assessed, using ELISA, in patients with unstable angina (UA, n=26), stable angina (SA, n=29) and in controls (C, n=27). All patients underwent coronary angiography. The extent of CAD was evaluated using a quantitative score, while the presence of complex, vulnerable plaques was angiographically assessed. Ox-LDL were higher in UA patients than in SA patients and in C subjects, and in SA patients than in C subjects (C, 45.6+/-12.8 U/L; SA, 58.8+/-11.0 U/L; UA, 73.7+/-13.6 U/L; p<0.001). No correlation was found with the extent of atherosclerotic disease in the coronary tree. Patients with angiographic complex lesions showed significantly higher levels of ox-LDL (68.4+/-13.9 U/L versus 55.2+/-16.4 U/L, p<0.001). Multiple regression analysis showed that ox-LDL were independent predictors of the presence of complex plaques (p<0.023)., Conclusions: Ox-LDL levels are higher in unstable patients and correlate with the presence of angiographically documented complex plaques. Ox-LDL might be markers of destabilization of CAD.

Lacidipine, a dihydropyridine-based calcium antagonist (DHP), has already been demonstrated to possess antioxidant activity and to reduce the intracellular production of reactive oxygen species (ROS). To verify if this effect is a peculiarity of this molecule, or belongs to other DHPs, the activity of lacidipine was compared with those of amlodipine, lercanidipine, nimodipine, and nifedipine. The DHPs were incorporated in bovine aortic endothelial cells (BAECs). Cu(2+)-oxidized LDL (ox-LDL, 5 microM) was incubated with BAECs for 5 min. 2',7'-Dichlorofluorescein (DCF) as expression of intracellular ROS production was measured by flow cytometry. Ox-LDL induced a strong increase in intracellular ROS formation (p<0.001) that was significantly reduced only with lacidipine and lercanidipine (p from <0.05 to <0.01); the effect of lacidipine, however, resulted in being much more evident than lercanidipine (p<0.01); amlodipine, nimodopine, and nifedipine had no effect on ROS formation. The lowest IC50s, i.e. the concentrations determining the 50% reduction of ROS, were obtained with lacidipine (p<0.01). The inhibitory effect of lacidipine on ox-LDL-induced ROS production in endothelial cells is a peculiarity of this molecule through its antioxidant activity.

Relationships between obesity and fat distribution as evaluated by computed tomography and metabolic variables were studied in 35 men. Significant correlations emerged between body mass index and sum of glucose during oral glucose load and HDL3 triglycerides and also between visceral abdominal fat and triglycerides, apolipoprotein B, sum of insulin during oral glucose load, very-low-density-lipoprotein (VLDL) cholesterol, and VLDL and low-density-lipoprotein (LDL) triglycerides. Visceral abdominal fat correlated negatively with the ratio of HDL to LDL cholesterol. When the subjects were subdivided into four groups according to body mass index (< or = 26.7, > 26.7) and median visceral abdominal fat, no significant differences were found in body mass index, whereas significant differences were found for triglycerides, cholesterol, apolipoprotein B, VLDL cholesterol, HDL:LDL cholesterol, and VLDL triglycerides. Our study shows that the amount of visceral abdominal fat is the most relevant factor for metabolic abnormalities. Our data also suggest that the effect of visceral fat is independent of body mass index.

Oxidative modification of low density lipoprotein (LDL) may play an important role in the mechanism of atherosclerotic damage to blood vessels. In the present study the LDL isolated from the plasmas of 73 coronary artery disease (CAD) patients, 28 valvular heart disease (VHD) patients, 59 subjects affected by type IIa hyperlipoproteinemia and 71 controls was oxidatively modified by incubation with copper ions. In 15 CAD and 15 Type IIa patients and 15 controls the LDL chemical composition and polyunsaturated fatty acid (PUFA) content were also measured. Differences in the LDL susceptibilities to lipid peroxidation were studied by measuring the changes of fluorescence intensity. The lag phase in the CAD patients was found to be significantly lower than in the VHD and controls (P < 0.001). The lag phase in the type IIa patients was significantly higher than in the CAD patients (P < 0.01), and significantly lower than the VHD and controls (P < 0.01). The LDL isolated from the type IIa patients had an increase in the relative content of free and esterified cholesterol (P < 0.05), while the CAD patients had a decrease in the relative content of free cholesterol (P < 0.05), and an increase in the relative content of protein (P < 0.05). The lowest value of the LDL cholesterol to protein ratio and LDL size, was found in the CAD patients (P < 0.05). When expressed in micrograms/mg LDL cholesterol, the concentration of the LDL PUFAs was significantly higher in the CAD group than in the others (P < 0.05). The LDL alpha-tocopherol concentration was quite similar in the different groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The predisposition to LDL oxidation during copper-catalyzed oxidative modification and its relationship with LDL alpha-tocopherol concentration was studied in 41 control subjects. The results show that the predisposition of LDL to oxidation expressed as duration of the inhibition period and rate of the propagation period varied greatly in the controls, but did not correlate with the values of LDL alpha-tocopherol. On the contrary the experiments with alpha-tocopherol incorporated in LDL demonstrate that even small increases of incorporated alpha-tocopherol, under circumstances where other variables were probably largely unaffected, increased proportionally the length of the inhibition period and reduced the rate of the propagation period. The values of LDL alpha-tocopherol achieved after the enrichment turned out to be positively correlated with the duration of the inhibition period and negatively with the rate of the propagation period. Finally the results of this study also show that there was a variability in the LDL alpha-tocopherol decay of different subjects under the same oxidative stress. In our conditions however, the time in which alpha-tocopherol contributed to the LDL protection was much shorter than the mean length of the inhibition period. The results demonstrate that the variability in the predisposition to LDL oxidation during copper-catalyzed oxidative modification is not determined only by the concentration of alpha-tocopherol in LDL and that therefore its value as a sole indicator of antioxidant status is probably inadequate.

When human low density lipoprotein (LDL) obtained from 10 volunteers was incubated in air at 37 degrees C in the presence of various concentrations of copper, an increase in fluorescence was observed with emission maximum at 430 nm when excitation was performed at 360 nm. The fluorescence increase was inhibited by ethylenediamine tetraacetic acid and by 4-methyl-2,6-di-tert-butylphenol. The fluorescence was found to be tightly bound to the protein moiety. Furthermore, Cu2+ modification of LDL was associated with a decrease in the reactive amino groups of apolipoprotein B and in the uptake of the lipoprotein by rabbit fibroblasts. Under our conditions, the fluorescence increase showed two consecutive periods; an inhibition period during which the fluorescence increased only weakly, and a propagation period with a rapid increase in fluorescence that was linear for at least 5 h. Both periods were influenced by copper concentration. The study also shows that the extent of fluorescence generated upon LDL oxidation varied greatly in the volunteers. Thus, while the results demonstrate that the fluorescence increase may likely monitor the extent of the apoB derivatization, the calculation of the fluorescence development rate of the propagation period together with the duration of the inhibition period may constitute a quantitative measurement of the susceptibility of apoB to be derivatized.

In recent years, guar gum has been shown to be a potent hypocholesterolemic agent. The effects of this fiber on triglycerides are less clear. In order to evaluate the influence of guar supplementation on plasma lipoproteins and apolipoprotein C-II (apoC-II) and apolipoprotein C-III (apoC-III) isoforms (apoC-III2, apoC-III1, apoC-III0), 16 g/day of guar gum were administered to 12 outpatients affected by familial combined hyperlipoproteinemia for a period of 60 days. Mean total cholesterol and triglyceride levels significantly decreased after 15 days of treatment and persisted reduced at the 30th and 60th day of guar supplementation. While low-density lipoprotein cholesterol paralleled the reduction of total plasma cholesterol, we did not observe any change in the cholesterol content of high-density lipoprotein (HDL) subfractions (HDL2 and HDL3) during the study. A redistribution of the relative content of very low-density lipoprotein apoC-III isoforms with a significant increase of apoC-III1 and a decrease of apoC-III0 was observed after 15, 30, and 60 days of guar gum administration. The results show that guar gum reduces not only cholesterol but also triglyceride levels in patients affected by familial combined hyperlipoproteinemia. Further studies are needed to confirm the suggestion that the different distribution of very low-density lipoprotein apoC-III isoforms induced by guar supplementation may influence the behavior of plasma triglycerides.

We evaluated the effect of a low-fat, high carbohydrate (LFHC) diet on plasma lipids in 10 patients affected by familial endogenous hypertriglyceridemia. All the patients studied underwent a base-line period of 4 wk, a 12-wk intervention period, and an 8-wk switch-back period. During the control periods patients consumed approximately 45% of energy as fat and approximately 40% as carbohydrate. During the intervention period they consumed an isocaloric diet containing approximately 25% of energy as fat and approximately 60% as carbohydrate. Total plasma triglyceride and cholesterol levels decreased significantly after 45 and 90 d of treatment (p less than 0.01). The reduction of plasma cholesterol was associated mostly with the decrease in VLDL cholesterol (p less than 0.01) while LDL cholesterol increased at days 45 and 90 of the LFHC diet (p less than 0.01). Finally, we observed a significant increase in HDL cholesterol both at days 45 and 90 of the LFHC diet (p less than 0.01). The LFHC diet we used may be an useful tool in the management of hypertriglyceridemia.