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BACKGROUND: Alcohol consumption is associated with increased high-density lipoprotein (HDL) cholesterol levels. One of the main antiatherogenic functions of HDL is reverse cholesterol transport. Three early steps of reverse cholesterol transport are (1) cellular cholesterol efflux, (2) plasma cholesterol esterification (EST), and (3) cholesteryl ester transfer (CET) to apolipoprotein B-containing lipoproteins. Our previous study in healthy middle-aged men showed that moderate alcohol consumption increases cellular cholesterol efflux and EST. This study investigated the effect of moderate alcohol consumption on three early steps of reverse cholesterol transport in postmenopausal women. METHODS: In a randomized crossover study, 18 postmenopausal women--all apparently healthy, non-smoking, and moderate alcohol drinkers--consumed white wine or white grape juice with evening dinner during 2 successive periods of 3 weeks. During the white wine period, alcohol intake equaled 24 g/day. At the end of each of the two experimental periods, blood samples were collected. RESULTS: Three weeks of alcohol consumption increased serum HDL cholesterol levels (5.0%; p < 0.05), serum HDL phospholipid levels (5.8%; p < 0.05), and the ex vivo cellular cholesterol efflux capacity of plasma, measured with Fu5AH cells (3.4%; p < 0.05). Plasma EST and CET did not change. CONCLUSIONS: Moderate alcohol intake increases serum HDL cholesterol level and stimulates cellular cholesterol efflux in postmenopausal women. Moderate alcohol consumption does not seem to affect two other early steps of reverse cholesterol transport at this level of alcohol intake. Our data suggest that the relative protection of moderate alcohol consumption against cardiovascular disease in postmenopausal women may involve the stimulation of reverse cholesterol transport through increased HDL. [ABSTRACT FROM AUTHOR]

Plasma levels of the vasoactive substance uridine adenosine tetraphosphate (Up 4 A) are elevated in hypertensive patients and Up 4 A-induced vascular contraction is exacerbated in various arteries isolated from hypertensive animals, suggesting a potential role of Up 4 A in development of hypertension. We previously demonstrated that Up 4 A produced potent and partially endothelium-dependent relaxation in the porcine coronary microvasculature. Since pressure-overload is accompanied by structural abnormalities in the coronary microvasculature as well as by endothelial dysfunction, we hypothesized that pressure-overload blunts the coronary vasodilator response to Up 4 A, and that the involvement of purinergic receptors and endothelium-derived factors is altered. The effects of Up 4 A were investigated using wire-myography in isolated coronary small arteries from Sham-operated swine and swine with prolonged (8 weeks) pressure overload of the left ventricle induced by aortic banding (AoB). Expression of purinergic receptors and endothelium-derived factors was assessed in isolated coronary small arteries using real-time PCR. Up 4 A (10 -9 to 10 -5 M) failed to produce contraction in isolated coronary small arteries from either Sham or AoB swine, but produced relaxation in preconstricted arteries, which was significantly blunted in AoB compared to Sham. Blockade of purinergic P1, and P2 receptors attenuated Up 4 A-induced coronary relaxation more, while the effect of P2X 1 -blockade was similar and the effects of A 2A - and P2Y 1 -blockade were reduced in AoB as compared to Sham. mRNA expression of neither A1, A2, A3, nor P2X 1 , P2X 7 , P2Y 1 , P2Y 2 , nor P2Y 6 -receptors was altered in AoB as compared to Sham, while P2Y 12 expression was higher in AoB. eNOS inhibition attenuated Up 4 A-induced coronary relaxation in both Sham and AoB. Additional blockade of cyclooxygenase enhanced Up 4 A-induced coronary relaxation in AoB but not Sham swine, suggesting the involvement of vasoconstrictor prostanoids. In endothelium-denuded coronary small arteries from normal swine, thromboxane synthase (TxS) inhibition enhanced relaxation to Up 4 A compared to endothelium-intact arteries, to a similar extent as P2Y 12 inhibition, while the combination inhibition of P2Y 12 and TxS had no additional effect. In conclusion, Up 4 A-induced coronary relaxation is blunted in swine with AoB, which appears to be due to the production of a vasoconstrictor prostanoid, likely thromboxane A 2 .

Excessive adventitial neovascularization is one of the hallmarks of atherosclerotic plaque progression and is associated with an increased plaque burden by facilitating leukocyte influx and perivascular inflammation. Statins act atheroprotective by reducing plasma cholesterol levels and by quenching inflammation, but recent studies suggest that they may also affect neovascularization. In this study, we aimed to investigate this notion in apoE(-/-) mice. Advanced carotid artery lesions were induced by perivascular collar placement in mice on western type diet or diet supplemented with atorvastatin (0.003%, w/w). Atorvastatin treatment did not affect diet induced body weight gain and did not lower plasma total cholesterol levels. Plaque size at 8 weeks after collar placement was significantly reduced in atorvastatin treated mice compared to control mice, while also necrotic core size was significantly lower in atorvastatin treated mice. Interestingly, atorvastatin treatment reduced the number of perivascular CD31(+) neovessels by almost 40%. Furthermore, endothelial proliferation was significantly inhibited by atorvastatin treatment in vitro. In conclusion, atorvastatin treatment inhibits plaque development in ApoE deficient mice independent of plasma total cholesterol levels. Given the profound inhibition of adventitial neovascularization, we propose that statins may partly exert their protective effects by modulating this process, identifying yet another atheroprotective mechanism for statins., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Aims: mast cells have been shown to accumulate in the adventitia of human atherosclerotic plaques and were recently demonstrated by us to contribute to plaque progression and instability. In this study, we investigated whether selective inhibition of mast cell chymases would affect the lesion development and stability., Methods and Results: the protease inhibitor RO5066852 appeared to be a potent inhibitor of chymase activity in vitro and ex vivo. With this inhibitor, we provide three lines of evidence that chymase inhibition can prevent many pro-atherogenic activities. First, oral administration of RO5066852 reduced spontaneous atherosclerosis in the thoracic aorta of apoE(-/-) mice. Second, chymase inhibition prevented the accelerated plaque progression observed in apoE(-/-) mice that were exposed to repetitive episodes of systemic mast cell activation. Furthermore, RO5066852 enhanced lesional collagen content and reduced necrotic core size. Third, RO5066852 treatment almost completely normalized the increased frequency and size of intraplaque haemorrhages observed in apoE(-/-) mice after acute perivascular mast cell activation in advanced atherosclerosis., Conclusion: our data indicate that chymase inhibition can inhibit pro-atherogenic and plaque destabilizing effects which are associated with perivascular mast cell activation. Our study thus identifies pharmacological chymase inhibition as a potential therapeutic modality for atherosclerotic plaque stabilization.

In many forms of congenital heart disease, the right ventricle (RV) is subject to abnormal loading conditions resulting in RV hypertrophy and remodeling. We determined the alterations in RV cytoplasmic proteomic phenotype that occur during prolonged periods of RV pressure overload. We performed a differential proteomic profiling study on RV hypertrophy using an animal model of various durations of pulmonary artery banding (PAB) in parallel with hemodynamic characterization. This hemodynamic evaluation showed that after 6, 12 and 20 weeks of PAB, the RV is in a compensated state of hypertrophy. Overall, the majority of protein changes were metabolism related indicating a shift towards the glycolytic pathway at the expense of beta-oxidation in the RV of the PAB animals. The changes in proteins related to the glycolytic pathway, exemplified by enolase and creatine kinase B-chain, tended to precede changes in beta-oxidation. In parallel, increases in stress chaperones, exemplified by several phosphorylated HSP-27 species, are present from the 6 week time point, whereas increases in antioxidant proteins, exemplified by peroxiredoxin 2 and 6, appear to be restricted to the 12 week time point. The p38 MAPK signal transduction pathway appears not to be activated. Observed protein changes are likely part of a protective mechanism against the development of RV failure.

In many patients with congenital heart disease, the right ventricle (RV) is subjected to abnormal loading conditions. To better understand the state of compensated RV hypertrophy, which could eventually progress to decompensation, we studied the effects of RV pressure overload in rats. In the present study, we report the biventricular adaptation to 6 wk of pulmonary artery banding (PAB). PAB resulted in an RV pressure overload to approximately 60% of systemic level and a twofold increase in RV mass (P < 0.01). Systemic hemodynamic parameters were not altered, and overt signs of heart failure were absent. Load-independent measures of ventricular function (end-systolic pressure-volume relation, preload recruitable stroke work relation, maximum first time derivative of pressure divided by end-diastolic volume), assessed by means of pressure-volume (PV) loops, demonstrated a two- to threefold increase in RV contractility under baseline conditions in PAB rats. RV contractility increased in response to dobutamine stimulation (2.5 microg.kg(-1).min(-1)) both in PAB and sham-operated rats in a similar fashion, indicating preserved RV contractile reserve in PAB rats. Left ventricular (LV) contractility at baseline was unaffected in PAB rats, although LV volume in PAB rats was slightly decreased. LV contractility increased in response to dobutamine (2.5 microg.kg(-1).min(-1)), both in PAB and sham rats, whereas the response to a higher dose of dobutamine (5 microg.kg(-1).min(-1)) was blunted in PAB rats. RV pressure overload (6 wk) in rats resulted in a state of compensated RV hypertrophy with preserved RV contractile reserve, whereas LV contractile state at baseline was not affected. Furthermore, this study demonstrates the feasibility of performing biventricular PV-loop measurements in rats.

The key components to the molecular understanding of the pathophysiology of various forms of heart failure involve global and/or large-scale identifications of proteins, their patterns of expression, posttranslational modifications, and functional characterization. Particularly, proteins involved in the induction of cardiac (mal)adaptive hypertrophic growth, interstitial fibrosis, and contractile dysfunction are of interest. In general, with the accumulation of vast amounts of DNA sequences in databases, researchers have become aware that merely having complete sequences of genomes and transcriptional changes for thousands of genes simultaneously will not be sufficient to elucidate, in molecular terms, the etiology and pathophysiology of cardiovascular disease. In the last decade, a new technology called proteomics has become available that allows biological and (patho)physiological questions to be approached exclusively from the protein perspective. Proteomics may enable us to map the entire complement of proteins expressed by the heart at any time and condition. This approach creates the unique possibility to identify, by differential analysis, protein alterations associated with the etiology of heart disease and its progression, outcome, and response to therapy. To illustrate the true power of proteomics, most of the currently available methodologies are first reviewed, including their limitations. This review also deals with the current status and the perspectives of proteomics applications in research on heart failure in general. Furthermore, examples of our recent data on global protein profiling of the pressure-overloaded rat right ventricle and of endothelin-1-stimulated cultures of neonatal rat cardiac myocytes are provided. The last section is devoted to the continuous advances in proteomic technologies, including protein separation methods, mass spectrometric instrumentation, computational analysis, and bioinformatic tools, together with integrative databases.

In humans, fibrates are used to treat dyslipidemia, because these drugs lower plasma triglycerides and raise HDL cholesterol. Treatment with fibrates lowers plasma phospholipid transfer protein (PLTP) activity in humans, but increases PLTP activity in mice, without a consistent effect on HDL-cholesterol concentration. Earlier, we found that PLTP overexpression in transgenic mice results in decreased plasma HDL levels and increased diet-induced atherosclerosis. So it seems that the interplay between fibrates, PLTP and HDL is different in mice and man, which may be important for atherosclerosis development. In the present study, we measured the effects of fibrates on PLTP expression in cultured human hepatocytes and effects of fibrate treatment on human PLTP expression, plasma PLTP activity and HDL levels in human PLTP transgenic mice. Fibrate treatment did not influence PLTP mRNA levels in human hepatocytes. Hepatic human PLTP mRNA levels and PLTP activity were both moderately elevated by fenofibrate treatment in human PLTP transgenic mice. In wild-type mice, however, feeding fenofibrate resulted in a strong induction of PLTP mRNA in the liver and a more than 4-fold increase of plasma PLTP activity. Plasma triglycerides were reduced in all mice by 48% or more by fenofibrate treatment. HDL-cholesterol concentrations were substantially increased by fenofibrate in PLTP overexpressing mice (+72%), but unaffected in wild-type mice. We conclude that fenofibrate treatment reverses the HDL-lowering effect of PLTP overexpression in human PLTP transgenic mice.

Right ventricular (RV) hypertrophy is an important problem in congenital heart disease. We determined the alterations in phenotype that occur in the initial phase of RV hypertrophy and their possible correlations with the degree of hypertrophy. Therefore, we performed a differential proteomic profiling study on RV hypertrophy using an animal model of pulmonary artery banding (PAB) in parallel with hemodynamic characterization. The RV homogenates were subfractionated in myofilament and cytoplasmic proteins, which subsequently were separated by two-dimensional gel electrophoresis (2-DE), excised, and analyzed by mass spectrometry (MS). The cytoplasmic fraction showed expression changes in metabolic proteins, indicative of a shift from fatty acid to glucose as a substrate for energy supply. Up-regulation of three HSP-27s (1.9-, 1.7-, and 3.5-fold) indicated an altered stress response in RV hypertrophy. Detailed analysis by immunoblotting and MS showed that two of these HSP-27s were at least phosphorylated on Ser15. The myofilament fraction showed up-regulation of desmin and alpha-B-crystallin (1.4-and 1.3-fold, respectively). This alteration in desmin was confirmed by 1-DE immunoblots. Certain differentially expressed proteins, such as HSP-27, showed a significant correlation with the RV weight to the body weight ratio in the PAB rats, suggesting an association with the degree of hypertrophy.

Acute myocardial infarction evokes activation of, among others, the arginine-vasopressin system, resulting in vasoconstriction and fluid retention. In the present study, the vasoconstrictor and antidiuretic effects of vasopressin were examined in vivo in conscious rats with chronic myocardial infarction, in the absence or presence of the V(1a) receptor antagonist SR-49059 or the V(2) receptor antagonist OPC-31260. In sham rats, vasopressin dose-dependently increased mean arterial pressure (maximum response: 45+/-3 mm Hg), which was significantly suppressed in infarcted rats (maximum response: 32+/-3 mm Hg). SR-49059, but not OPC-31260, caused a significant rightward shift of the dose pressure response curve in sham rats, indicating V(1a) receptor mediation. This rightward shift by SR-49059 was significantly more in infarcted rats. The suppressed response to the agonist and enhanced sensitivity to the antagonist suggest a reduction of V(1a) receptor number in infarcted rats. In both sham and infarcted rats, the urine production after OPC-31260 (337+/-14 and 329+/-30 microl/min, respectively) was about twice of that in vehicle-treated rats (188+/-25 and 155+/-24 microl/min, respectively). However, the response in infarcted rats reached its peak quicker and lasted for a shorter period, resulting in a 40% lower area under the curve. Although only measurable during V(2) receptor blockade, the reduction of urine production by vasopressin was significantly more in infarcted compared to sham rats. The enhanced renal response to the agonist and reduced response to the antagonist suggest an increase in V(2) receptor number in infarcted rats. In conclusion, in chronically infarcted rats, vasopressin causes vasoconstriction and fluid retention through the V(1a) and V(2) receptors, respectively. Altered responses after infarction indicate a shift from V(1a) to V(2) receptors.

After myocardial infarction, plasma levels of [Arg8]-vasopressin rise to recover hemodynamics. The vascular responses to [Arg8]-vasopressin were studied in vitro in isolated hearts and mesenteric artery segments of rats with 1-day and 3-week-old infarcts, in absence and presence of the V1a-receptor antagonist SR-49059 and the V2-receptor antagonist OPC-31260. Vascular responses of coronary arteries were similar in sham and infarcted hearts. On average, coronary flow was maximally decreased by 70 +/- 3% from baseline values of 11.1 +/- 0.3 ml/min, with pD2 values of 10.52 +/- 0.05. In mesenteric artery segments of sham and infarcted rats, maximal contractile forces, expressed as percentage of contraction to 125 mM KCl, were similar (232 +/- 23% and 239 +/- 8%, respectively). However, pD2 values from infarcted rats (9.22 +/- 0.07) were significantly lower compared with sham (9.55 +/- 0.07) rats. In coronary as well as mesenteric vessels, the vasoconstrictor responses, being more susceptible to SR-49059 (apparent pA2, between 9.12 and 9.82) than to OPC-31260 (apparent pA2, between 6.21 and 6.92), seemed mediated by the V1a receptor. These data indicate that in mesenteric but not in coronary vessels, an altered responsiveness to vasopressin could be observed. Responses are mediated mainly by the V1a receptor.